Dissertations / Theses: 'Medical / Laboratory Medicine'

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Suwarno, Neihl Omar 1963. "A computer based data acquisition and analysis system for a cardiovascular research laboratory." Thesis, The University of Arizona, 1989. http://hdl.handle.net/10150/558111.

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Zurgani, Emad K. A. "Documentation of the body transformations during the decomposition process : from the crime scene to the laboratory." Thesis, University of Huddersfield, 2018. http://eprints.hud.ac.uk/id/eprint/34690/.

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Forensic science is defined as the application of scientific or technical practices to the recognition, collection, analysis, and interpretation of evidence for criminal and civil law or regulatory issues. A combination of computer science in the field of 3D reconstruction and molecular biology science and techniques were employed in this research aims to document and record a complete picture of the body decomposition process including the changes of the microbiome over the decomposition process. In this thesis, the possibility to reconstruct the crime scene and the decomposition process was investigated. In addition, a 3D model aiming to integrate the biological and thanatological information was generated. The possibility of utilising Autodesk 123D Catch software as a new tool for 3D reconstruction of a crime scene was thoroughly evaluated. First experiments demonstrated that the number of photos required to obtain the best result was specified to be from 20 to 30 photos as a minimum. In addition, significant experiments were performed in different conditions of sizes, locations, and different involved materials. The measurements were obtained from the models using the same software were compared with the real measurements of the tested objects. The result of the correlation between real and estimated measurements showed a very strong agreement ranging from 0.994 to 1.000. With reference to the documentation of the decomposition process, there are different factors, intrinsic and extrinsic, have been reported affecting the decomposition of a carrion/body. These factors mainly interact with the rates of the biological and chemical reaction happening after death. The biological reactions are mainly due to the activity of microorganism and insects. Pigs (Sus scrofa domesticus) were used as a model for human studies and the results obtained have been applied to other mammals without considering the effect of fur on the decomposition process and on the insect and microbial colonisation. In order to investigate this point, rabbits (Oryctolagus cuniculus) with and without fur were used in two sets of experiments at Huddersfield in summer 2014 and in spring 2015. The results obtained in this study showed a similarity of the decomposition stages between animals with and without fur. However, the decomposition process was faster during the summer due to the fast of insect colonisation and activity. In addition, the entomological data collected during the summer and spring experiments were demonstrated that the same taxa nearly were present in both seasons, except Hydrotaea (Diptera, Muscidae), which was presented only in the summer experiment, moreover, only one sample of Lucilia sericata (Calliphoridae) was detected in the spring season. Differences in colonisation time were observed only in spring experiment; animals without fur were colonised two days before animals with fur. The season could have affected the insect’s activity and the spread of the decomposition volatiles. The microbial communities during the decomposition process were investigated using BIOLOG EcoPlateTM and the hypervariable V1-3 region of 16S rRNA gene was used for their molecular identification based on pyrosequencing. Eurofins Genomic Operon using 454-GS Junior pyrosequencing platform (Roche) carried out these analyses. The functional diversity of the bacterial communities on all carcasses samples showed a considerable variability depending on the stage of the decomposition and the sampling region (Oral cavity, skin and interface-sand-carrion) in both seasons. Furthermore, over the molecular analyses of bacterial communities at the phylum level, four main phyla of bacteria were detected among analysed carrion during the decomposition process. These phyla were changed significantly during the stages of the decomposition and between sampling regions. While no difference was observed due to presence or absence of fur. On the other hand, the analysis at the family level was able to highlight differences at the temporal scale but as well as carrion with and without fur. The statistical analysis results showed a significant difference in the bacterial community family distribution among the presence of fur and among the decomposition stages, with significant differences among sampling regions and seasons.

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Small, Kathy S. "Retention Strategies for Medical Technologists: Addressing the Shortages and Vacancies in the Clinical Laboratory." Digital Commons @ East Tennessee State University, 2013. https://dc.etsu.edu/etd/2299.

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It is important to have well-trained and qualified laboratory professionals. Seventy percent of patient care is based on decisions made from laboratory results, yet there is a growing shortage of medical technologists. Although some baby boomers are delaying retirement, worsening of the shortage crisis is inevitable. Retention of medical technologists has become more important than recruitment. The purpose of this study was to identify and evaluate innovative retention strategies used by clinical laboratory managers throughout the United States. A significant finding of this study was the lack of qualified medical technologists entering the ranks of laboratory managers. This study identified a need for a more defined career path and more recognition of the importance of laboratory scientists. It is recommended that studies be undertaken to examine the opinions of hospital and medical group practice administrators as well as the view of medical technologists regarding retention strategies that are proven to be effective.

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O'Connell-Spalla, Joan. "Medical Laboratory Testing Personnel: Perception of Professional Status and Engagement in Professional Development and Career Advocacy." Youngstown State University / OhioLINK, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=ysu1627410209680141.

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De, Beer Corena. "Clinical and laboratory investigation of latex allergy in healthcare workers." Thesis, Stellenbosch : Stellenbosch University, 2004. http://hdl.handle.net/10019.1/49883.

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Thesis (PhD)--Stellenbosch University, 2004.
ENGLISH ABSTRACT: Healthcare workers (HCWs) wear latex gloves to protect themselves and their patients against the transmission of microbial, viral and bloodborne diseases. These individuals are primarily exposed to latex via cutaneous (direct contact) and mucocutaneous (inhalation of airborne allergens on glove powder) routes. Repeated exposure leads to the formation of circulating latex-specific IgE and subsequent sensitisation with varying clinical expression. The airconditioning system of the Tygerberg Hospital (TBH) complex was investigated for the presence of aerosolised cornstarch glove powder and proteins. Dust samples were collected from 14 areas with different levels of latex glove usage. Dust samples were spectrophotometrically compared to a calibration graph of pure glove powder. The detection of starch and proteins in all the dust samples confirmed the presence of glove powder and possibly airborne latex allergens in the airconditioning ducts. As expected, the high exposure areas showed the highest concentrations of both starch and proteins. It is possible that other proteins than latex were involved, but the confirmed high level of protein contamination should be a cause for concern. Correlation between starch and protein levels was highly significant (p<0.01) in all instances. A total of 500 questionnaires were circulated for completion by HCWs from TBH. The response rate was 69.8%. After considering specific inclusion criteria, a study group of 152 individuals was compiled (28 males, 124 females). All subjects had current latex exposure and suffered from at least three pre-defined symptoms. Serum was collected from all subjects and dermal fluid from 31 subjects. Total IgE and latex specific IgE analysis were done on all serum and dermal fluid samples. Latex-specific IgE was positive (>0.35 IU/ℓ) in 23 serum and six dermal fluid samples. Skin prick tests (SPTs)for latex were done on 59 subjects with negative serum latex-specific IgE and 34 had positive results. Twelve subjects with negative latex-specific IgE and latex SPTs underwent patch tests with the European Standard Series, a piece of latex glove and glove powder in petrolatum. Three subjects had positive results to one or more of these allergens. Western blot analysis for latex was done on all positive sera and dermal fluid collected from these subjects. Western blot analysis for latex proved to be more sensitive than the capRAST, because it was able to identify specific bands in samples with negative capRAST results. All subjects showed a band for Hev b 1, which has been confirmed as a powder-bound airborne allergen. Hev b 6.01 is associated with HCWs with cutaneous symptoms and this band was recognised by 81% of the subjects. These findings confirmed that airborne and cutaneous routes are the major routes of exposure in HCWs. According to their laboratory results, subjects were divided into the following subgroups and compared statistically: Group A (serum positive, n=23), Group B (SPT positive, n=34) and Group C (negative, n=25). Group D (withdrawn, n=70) could not be used for statistical comparisons, due to incomplete results. An overall latex allergy prevalence of 38% was found. Group A differed significantly from Group B and Group C for most clinical and special investigations. Group A and B were also combined to represent all subjects with positive results (Cohort AB). The Allergy Score and Class were highly significant when Cohort AB was compared to Group C. The selection of clinical symptoms was confirmed to be relevant and work-related deterioration on any of the symptoms should bear a high index of suspicion in the evaluation of latex allergy. Numerical indices and specific symptoms showed high positive predictive values and the Allergy Score produced statistical significance in the positive subgroups when compared to the negative subgroup. Paired statistical significance was confirmed between the Allergy Score and occupational exposure (number of years, hours and pairs per week). The areas with the highest occupational latex exposure in HCWs are the face and hands. Different occupations also have different levels of exposure and two subgroups of HCWs (16 laboratory technologists and 13 theatre staff) were investigated for sebum content on different facial areas and the palms and dorsal areas of both hands. Baseline measurements were done before putting on gloves. In 21 subjects follow up measurements were done following three to four hours of occupational exposure, but before washing their hands. Baseline and follow up values were compared for all the different anatomical regions. Levels on the forehead and cheeks increased over time, while the level on the nose decreased. All hand regions decreased significantly during occupational exposure, suggesting that glove powder contributes to dryness of the skin. In conclusion, the problem posed by latex allergy will not be solved overnight and will probably remain a major occupational hazard for years to come. It is currently not possible to avoid exposure to latex, but it is imperative to institute safety measures to prevent further sensitisation in predisposed individuals and manage those already affected.
AFRIKAANSE OPSOMMING: Gesondheidswerkers dra lateks handskoene om hulleself en hulle pasiënte te beskerm teen die oordrag van mikrobiale, virale en bloed-gedraagde siektes. Die lateks blootstelling vind hier hoofsaaklik plaas via kutane (direkte velkontak) en mukokutane (inaseming van lug-gedraagde allergene op hanskoen poeier) roetes. Herhaalde blootstelling veroorsaak sirkulerende lateksspesifieke IgE en sensitisasie met variërende kliniese beelde. Die lugreëlingstelsel van die Tygerberg hospitaalkompleks is ondersoek vir die teenwoordigheid van handskoenpoeier (stysel) en lateks proteïene. Stofmonsters is versamel in 14 areas wat verskillende blootstellingsvlakke verteenwoordig het. Die stofmonsters is spektrofotometries vergelyk met "n kalibrasiekurwe van suiwer hanskoenpoeier. Stysel en proteïene kon in al die stofmonsters aangetoon word en het die teenwoordigheid van handskoenpoeier en moontlike luggedraagde lateks proteïene in die lugreëlingstelsel bevestig. Soos verwag kon word, het die hoogste stysel en proteïen waardes in hoë blootstellingsareas voorgekom. Hoogs beduidende statistiese korrelasies (p<0.01) tussen die stysel en proteïenvlakke kon aangedui word in alle monsters. "n Totaal van 500 vraelyste is gesirkuleer vir voltooiing deur TBH gesondheidswerkers, waarvan 69.8% voltooide vraelyste terugontvang is. Na evaluering van insluitingskriteria, is "n studiegroep van 152 individue saamgestel (28 mans, 124 vrouens). Almal het huidige lateks blootstelling en ten minste drie het vooraf gedefinieerde simptome gerapporteer. Serum is van die hele groep versamel en dermale vog van 31 proefpersone. Totale IgE en lateks-spesifieke IgE vlakke is op alle serum en dermale vog bepaal. Positiewe resultate (>0.35 IU/ℓ) is verkry in 23 serum en ses dermaIe vog monsters. Velpriktoets vir lateks is op 59 proefpersone uitgevoer en 34 daarvan het positiewe resultate opgelewer. Twaalf proefpersone met negatiewe lateks-spesifieke IgE en velpriktoets resultate het kutane plaktoetse ondergaan met die Europese Standaard Reeks, "n stukkie lateks handskoen en handskoenpoeier in petrolatum. Drie proefpersone het positiewe resultate teen een of meer van die allergene gehad. Westerse kladanalise vir lateks is op alle positiewe serum gedoen, asook die dermale vogte van hierdie proefpersone. Westerse kladanalise vir lateks blyk baie meer sensitief te wees as die capRAST, aangesien dit spesifieke bande kon identifiseer in monsters capRAST resultate. Alle monsters het "n band getoon vir Hev b 1, "n poeier-gebinde, luggedraade allergeen. Hev b 6.01 is geassosieer met gesondheidswerkers met velsimptome en hierdie band is gevind in 81% van die monsters. Hierdie resultate bevestig dat die belangrikste blootstelling aan lateks in gesondheidswerkers deur die vel en inaseming plaasvind. Proefpersone is in die volgende drie groepe verdeel volgens laboratorium resultate en statisties vergelyk: Groep A (positiewe serum, n=23), Groep B (positiewe velpriktoetse, n=34) en Groep C (negatief, n=25). Groep D (onttrek, n=70) kon nie vir betekenisvolle statistiese vergelykings aangewend word nie, as gevolg van onvolledige resultate. 'n Finale lateks allergie prevalensie van 38% is gevind. Groep A het hoogs beduidend verskil van Groep B en C vir die meeste van die kliniese en spesiale laboratoriumondersoeke. Groep A en B is gekombineer om alle proefpersone in te sluit met positiewe resultate (Kohort AB). Die Allergie Telling en Klas van Kohort AB was hoogs beduidend in vergelyking met Groep C. Die gekose simptome is bevestig as relevant en enige werksverwante verergering van simptome moet met 'n hoë mate van agterdog bejeën word in lateks allergie. Numeriese indekse en spesifieke simptome het hoë positiewe voorspellingswaardes gelewer en die Allergie Telling was hoogs beduidend in die positiewe subgroep in vergelyking met die negatiewe subgroep. Gepaarde statistiese beduidenheid is ook gevind tussen die Allergie Telling en beroepsblootstelling (jare van blootstelling, uur en paar handskoene per week). Die meeste beroepsblootstelling aan lateks in gesondheidswerkers vind plaas op die hande en gesig. Verskillende beroepe het ook verskillende blootstellingsvlakke en two subgroepe gesondheidswerkers (16 laboratorium tegnoloë en 13 teater personeel) is ondersoek vir die sebumgehalte op veskillende areas van die gesig en hande. Basislynvlakke is gemeet voordat handskoene aangetrek is en in 21 gevalle is opvolgvlakke gemeet na drie tot vier uur beroepsblootstelling, maar voor die hande gewas is. Basislyn en opvolgvlakke is met mekaar vergelyk vir al die anatomiese areas. Die voorkop en wange het 'n toename in sebumgehalte getoon, terwyl dié van die neus afgeneem het. AI die areas op die hande toon 'n hoogs beduidende afname tydens beroepsblootstelling, wat impliseer dat hanskoenpoeier moontlik bydra tot droogheid van die vel. In samevatting, die lateks allergie probleem sal nie oornag opgelos word nie en sal waarskynlik 'n belangrike beroepsrisiko bly vir die aansienlike toekoms. Totale vermyding van lateks is tans onmoontlik en daarom is dit van uiterste belang om voorsorgmaatreëls in plek te stel om verdere sensitisasie in blootgestelde individue te verhoed en die wat reeds geaffekteer is, effektief te hanteer.

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Forsgren, Mikael. "The Non-Invasive Liver Biopsy : Determining Hepatic Function in Diffuse and Focal LiverDisease." Doctoral thesis, Linköpings universitet, Avdelningen för radiologiska vetenskaper, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-136545.

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The liver is one of the largest organs within the human body and it handles many vital tasks such as nutrient processing, toxin removal, and synthesis of important proteins. The number of people suffering from chronic liver disease is on the rise, likely due to the present ‘western’ lifestyle. As disease develops in the liver there are pathophysiological manifestations within the liver parenchyma that are both common and important to monitor. These manifestations include inflammation, fatty infiltration (steatosis), excessive scar tissue formation (fibrosis and cirrhosis), and iron loading. Importantly, as the disease progresses there is concurrent loss of liver function. Furthermore, postoperative liver function insufficiency is an important concern when planning surgical treatment of the liver, because it is associated with both morbidity and mortality. Liver function can also be hampered due to drug-induced injuries, an important aspect to consider in drug-development. Currently, an invasive liver needle biopsy is required to determine the aetiology and to stage or grade the pathophysiological manifestations. There are important limitations with the biopsy, which include, risk of serious complications, mortality, morbidity, inter- and intra-observer variability, sampling error, and sampling variability. Cleary, it would be beneficial to be able investigate the pathophysiological manifestations accurately, non-invasively, and on regional level. Current available laboratory liver function blood panels are typically insufficient and often only indicate damage at a late stage. Thus, it would be beneficial to have access to biomarkers that are both sensitive and responds to early changes in liver function in both clinical settings and for the pharmaceutical industry and regulatory agencies. The main aim of this thesis was to develop and evaluate methods that can be used for a ‘non-invasive liver biopsy’ using magnetic resonance (MR). We also aimed to develop sensitive methods for measure liver function based on gadoxetate-enhanced MR imaging (MRI). The presented work is primarily based on a prospective study on c. 100 patients suffering from chronic liver disease of varying aetiologies recruited due to elevated liver enzyme levels, without clear signs of decompensated cirrhosis. Our results show that the commonly used liver fat cut-off for diagnosing steatosis should be lowered from 5% to 3% when using MR proton-density fat fraction (PDFF). We also show that MR elastography (MRE) is superior in staging fibrosis. Finally we presented a framework for quantifying liver function based on gadoxetate-enhanced MRI. The method is based on clinical images and a clinical approved contrast agent (gadoxetate). The framework consists of; state-of the-art image reconstruction and correction methods, a mathematical model, and a precise model parametrization method. The model was developed and validated on healthy subjects. Thereafter the model was found applicable on the chronic liver disease cohort as well as validated using gadoxetate levels in biopsy samples and blood samples. The liver function parameters correlated with clinical markers for liver function and liver fibrosis (used as a surrogate marker for liver function). In summary, it should be possible to perform a non-invasive liver biopsy using: MRI-PDFF for liver fat and iron loading, MRE for liver fibrosis and possibly also inflammation, and measure liver function using the presented framework for analysing gadoxetate-enhanced MRI. With the exception of an MREtransducer no additional hardware is required on the MR scanner. The liver function method is likely to be useful both in a clinical setting and in pharmaceutical trials.

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Mukinda, James Tshikosa. "Acute and chronic toxicity of the flavonoid-containing plant, Artemisia afra in rodents." Thesis, University of the Western Cape, 2005. http://etd.uwc.ac.za/index.php?module=etd&amp.

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The aim of this study was to investigate the possible toxicity of the flavonoid-containing plant, Artemisia afra and especially establish the safety of the aqueous extract of this plant after acute and chronic administration to mice and rats respectively.

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Lundström, Jonathan, and Joel Skagersten. "Optimering samt implementering av Harts automatiserade färgningsmetod : Ersättning av Verhoeffs manuella elastinfärgning." Thesis, Jönköping University, HHJ, Avd. för naturvetenskap och biomedicin, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:hj:diva-52932.

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Elastinfibrer ger blodkärl och andra vävnader deras flexibilitet. Elastinfärgning är relevant när man misstänker melanom, temporalis artrit, venös invasion och efter blodkärlsoperationer. Syftet var att med hjälp av olika vävnadstyper optimera och implementera den automatiserad elastinfärgningen enligt Hart, för att ersätta den nuvarande manuella elastinfärgning enligt Verhoeff vid patologilaboratoriet på länssjukhuset Ryhov, Jönköping. Colon, njure, hud samt navelsträng färgades med den automatiska metoden enligt Hart för att hitta optimala inställningar. Vävnader från samma områden färgades med den manuella metoden enligt Verhoeff samt den automatiska metoden enligt Hart för att jämföra dem. Snitten bedömdes av en läkare så allt färgades som det skulle. Optimeringen av Harts metod resulterade i en inkubationstid på tolv minuter samt en optimal färgningsbehandling utan xylen. Resultaten av jämförelsen mellan den automatiska metoden enligt Hart och den manuella metoden enligt Verhoeff visar att den automatiska metoden enligt Hart ger bättre kontrast samt bakgrundsinfärgning. Slutsatsen blev att den automatiska metoden enligt Harts var bättre än den manuella metoden enligt Verhoeff, att i framtida studier studera möjligheten att byta ut läskningen mot till exempel ytterligare ett etanoldop samt att byta ut snitten av navelsträngen mot snitt av lever.
Elastic fibres ensure blood vessels and other tissues flexibility. Elastic staining of tissue is relevant when there is suspicion of melanoma, temporalis arteritis, venous invasion and after operations on blood vessels. The aim of the study was with the help of different tissue samples optimize and implement Hart´s elastic staining method as a substitute for Verhoeff’s at pathology lab at county hospital Ryhov, Jönköping. Colon, kidney, skin, and umbilical cord cross section got stained with Hart´s automated elastic staining method to evaluate the optimal staining procedure. Same region of the tissues was stained with Verhoeff´s manual elastic staining method and Hart´s method. All cross section were assessed and compared with the help of a pathologist doctor. Optimization of Hart´s method resulted in an incubation period of twelve minutes and optimal staining procedure without xylene. Result of comparison between Hart´s staining method and Verhoeff´s staining method showed that Hart´s staining method had a better contrast and background. Conclusions of the study was that Hart´s staining method was better than Verhoeff´s staining method, further studies could include research about a substitution of the blotting step with an extra ethanol bath as an example and liver tissue instead of the umbilical cord.

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Prince, Yvonne. "Improving laboratory techniques to detect M. tuberculosis complex and C. neoformans as the causative agents of chronic meningitis in cerebrospinal fluid of adult patients." Thesis, Stellenbosch : University of Stellenbosch, 2010. http://hdl.handle.net/10019.1/4110.

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Thesis (MScMedSc (Pathology. Medical Microbiology))--University of Stellenbosch, 2010.
ENGLISH ABSTRACT: INTRODUCTION Mycobacterium tuberculosis (MTB) and Cryptococcus neoformans are the most common causes of chronic meningitis in South Africa. Conventional microbiology has limited utility in diagnosing these pathogens due to the paucibacillary nature of cerebrospinal fluid (CSF) and the diagnostic delay associated with culturing methods. This study aimed to evaluate the utility of an in-house polymerase chain reaction (PCR) method for the detection of the etiological agent of chronic meningitis. METHODS CSF samples (where volume exceeded 5ml) were submitted to the Medical Microbiology diagnostic laboratory of the Tygerberg Hospital from patients with suspected tuberculosis meningitis (TBM). Following routine bacteriology, the sample was used to inoculate two mycobacterial growth indicator tubes (MGIT A and B) and subsequently incubated in the BACTEC 960 automated system. MGIT A followed standard operating procedures and the time to culture positivity was noted. Weekly aliquots (up to 6 weeks) were removed from MGIT B. These samples were boiled to inactivate the bacteria and then the DNA was extracted using the Promega Wizard SV Genomic DNA kit. The DNA was then speciated by PCR and high-resolution melting analysis (HRM) by using primers specific to either the RD9 region of MTB complex or primers specific to the partial internal transcribed spacer 1 (ITS1), 5.8S rRNA gene and partial ITS2 sequence of C. neoformans. RESULTS Routine CSF microscopy indicated that 14 of the 78 patients (17.9%) had typical CSF findings of TBM (lymphocytes predominant, increased protein levels and decreased glucose levels). IV Ziehl-Neelsen (ZN) stains were positive for 12 (15.4%) samples, and MTB was cultured from 19 samples (24.4%). Our optimized PCR and HRM method was able to detect M. tuberculosis in 17 of the 19 culture positive specimens with a sensitivity of 89.5% and a specificity of 62.7%. The sensitivity of this method was higher than that of direct microscopy. In all of the PCR positive samples, the time to detection, compared to culture, could be shortened by 1 to 2 weeks. Only one sample was positive for Cryptococcus culture and another sample was positive with a Cryptococcus latex test. PCR for Cryptococcus was positive in 2 cases (n=78), sensitivities and specificities could not be reported due to the low number of positive cases. CONCLUSION We demonstrated that a short culture period and the use of commercial DNA extraction kit on CSF samples increases the sensitivity of molecular tests to diagnose tuberculosis. Furthermore, the molecular techniques could significantly reduce the time to positivity of results, when compared to culture. Due to the low occurrence of Cryptococcus in the samples included in our study, we could not comment on the diagnostic utility of PCR in the diagnosis of Cryptococcal meningitis, when compared to the conventional methods.
AFRIKAANSE OPSOMMING: INLEIDING Mycobacterium tuberculosis (MTB) en Cryptococcus neoformans is die mees algemeenste oorsake van kroniese meningitis in Suid-Afrika. Routine mikroskopie dra beperkte waarde in die diagnose van hierdie patogene as gevolg van die klein hoeveelhede organismes wat in die SSV (serobrospinale vog) voorkom en die lang tyd wat dit benodig om hierdie organisms te kweek. Hierdie studie beoog om die diagnostiese waarde van ‘n polymerase ketting reaksie (PKR) metode wat intern ontwerp is te evalueer vir die identifikasie van patogene verantwoordelik vir kroniese meningitis. METODES SSV monsters (waarvan die volume 5ml oorskry) en waar daar ‘n kliniese vermoede van tuberkulose meningitis (TBM) was, is na die diagnostiese Mediese Mikrobiologie laboratorium van Tygerberg hospitaal gestuur vir roetine bakteriologiese ontleding. Die oorblywende monsters is gebruik om twee mikobakteriële groei-indikasiebuise (MGIT A en B) te innokuleer en hulle is geïnkubeer in ‘n BACTEC 960 geautomatiseerde sisteem. MGIT A is volgens roetine diagnostiese metodes geanaliseer en die tyd tot ‘n positiewe resultaat is aangeteken Weeklikse monsters (tot en met week 6) is uit MGIT B verwyder en die monsters is gekook om sodoende die bakterië te inaktiveer. Die Promega Wizard SV Genomiese DNS ekstraksiemetode is gebruik om die DNS te versuiwer. Spesiëring van die DNS is deur middel van ‘n intern ontwerpte PKR en hoëresolusiesmeltingsmetode (HRS) gedoen met inleiers wat spesifiek is tot die RD9 gedeelte van die MTB kompleks en inleiers spesifiek tot die gedeeltelike interne getranskribeerde spasieerder 1 (ITS1), 5.8S rRNS geen en die gedeeltelike ITS2 DNS volgorde van C. neoformans. VI RESULTATE Roetine SSV mikroskopie het aangedui dat 14 uit 78 (17.9%) pasiënte tipiese SSV bevindings van TBM (oorwegend limfosiete, verhoogde proteïene en verlaagde glukose) gehad het. Ziehl- Neelsen (ZN) kleurings was positief vir 12 (15.4%) monsters, en MTB is gekweek in 19 (24.4%) van hierdie monsters. Ons geoptimaliseerde PKR en HRS metode het daarin geslaag om M. tuberculosis in 17 van die 19 kultuurpositiewe monsters aan te toon met ‘n sensitiviteit van 89.5% en ‘n spesifisitiet van 62.7%. Die sensitiwiteit van die direkte PKR was hoër in vergelyking met mikroskopie. In al die PKR positiewe monsters was die tyd tot aantoning, in vergelyking met kultuur, verkort met 1 tot 2 weke. Slegs een monster het C. neoformans gekweek en ‘n ander monster was positief met die kriptokokkale latekstoets. PKR vir C. neoformans was positief in 2 gevalle (n=78). Die sensitiwiteit en spesifisiteit van die C. neoformans PKR kon nie bepaal word nie weens te min gevalle. GEVOLGTREKKINGS Ons het aangetoon dat ‘n verkorte inkubasieperiode en die gebruik van ‘n kommersiële DNS ekstraksiemetode op SSV monsters die sensitiwiteit van die molekulêre tegniek vir die diagnose van tuberkulose verhoog en dat hierdie metode die tyd na positiwiteit aansienlik verkort in vergelyking met kultuur. Weens die lae getalle van kriptokokkale meningitis in ons studie kon ons nie kommentaar lewer op die akkuraatheid van PKR in die diagnose van kriptokokkale meningitis, in vergelyking met meer konvensionele metodes, nie.

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Van, Vuuren Petra J. "The effects of physical and psychological stress on the behaviour and neurochemistry of rats." Thesis, Link to the online version, 2005. http://hdl.handle.net/10019/1274.

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Leclair, Susan J. "The Correlation Between the Levels of Education of Clinical Laboratory Personnel and the Accuracy of Peripheral Blood Smear Results." ScholarWorks, 2001. https://scholarworks.waldenu.edu/dissertations/1393.

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This study correlated the performance accuracy of peripheral blood differentials evaluated by clinical laboratory scientists and clinical laboratory technicians. Fifty-one senior-year students from four clinical laboratory science baccalaureate programs and 37 second-year students from five clinical laboratory technician programs were given 10 peripheral blood differentials to perform. Results were compared to the values assigned by the Rajamaki method of proficiency testing. There was a significant discrepancy in the levels of accuracy between the two cohorts, suggesting that the results of peripheral blood differentials performed by clinical laboratory technicians is suspect. Facilities wishing to maintain or improve the quality of laboratory services should consider allowing only baccalaureate level clinical laboratory scientists to perform peripheral blood differentials.

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Lumkwana, Dumisile. "Identifying appropriate attachment factors for isolated adult rat cardiomyocyte culture and experimentation." Thesis, Stellenbosch : Stellenbosch University, 2014. http://hdl.handle.net/10019.1/86479.

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Thesis (MScMedSc)--Stellenbosch University, 2014.
ENGLISH ABSTRACT: Introduction: Primary culture of isolated adult rat cardiomyocytes (ARCMs) is an important model for cardiovascular research, but successful maintenance of these cells in culture for their use in experiments remains challenging (Xu et al, 2009; Louch et al, 2011). Most studies are done on acutely isolated cardiomyocytes immediately after isolation, which is due to low survival of these cells in culture. Obstacles in culture are due to the type of medium and attachment factors (tissue culture adhesives) used to culture and grow these cells. Although we previously identified an optimum medium and adhesive for culture, an adhesive that permits cells to remain attached to the culture surface until after an ischemia/reperfusion insult was elusive. Aims: We therefore aimed to identify the best attachment factor and concentration that will allow adult rat cardiomyocytes to remain attached to the culture surfaces after ischemia/reperfusion experiments. Methods: Cardiomyocytes were isolated from adult Wistar rat hearts and cultured overnight on different concentrations (25 -200 μg/ml) of collagen 1, collagen 4, extracellular matrix (ECM), laminin/entactin (L/E) and laminin. Following overnight cultures, experiments were done in PBS and in PBS versus MMXCB to compare ARCM attachment and viability. Cardiomyocytes cultured on ECM, L/E and L (25−200μg/ml) were subjected to 1 hour of simulated ischemia using MMXCB that contained 3mM SDT and 10mM 2DG, followed by 15 minutes reperfusion. Cell viability was determined by staining cells with JC-1 and images of cells in a field view of 1.17μm/mm2 were captured using fluorescence microscopy. The cells were analysed according to morphology and fluorescence intensity. Results: Total and rod-shaped ARCMs attachment was improved when MMXCB was used as an experimental buffer instead of PBS. Regardless of the buffer used, morphological viability was poor on substrates of Col 1 and Col 4. In contrast to collagens, ARCMs attached efficiently and morphological viability was high on substrates of ECM, L/E and L in MMXCB, but this was greatly reduced in PBS. Mitochondrial viability was high in MMXCB compared to PBS on Col 1 and Col 4 at 75−175μg/ml and on ECM, L/E and L at all concentrations, except at 50 and 150μg/ml ECM, 175μg/ml L/E and 25μg/ml L. When cardiomyocytes cultured on ECM, L/E and L were subjected to simulated ischemia, total ARCMs, rod-shaped and R/G fluorescence (mitochondrial viability) was reduced at all concentrations compared to the control group. Hypercontracted cells were higher in the ischemic treated cells compared to the controls on ECM at 75−150μg/ml and 200μg/ml, L/E at 50,100μg/ml and 175μg/ml and on L at 125μg/ml. Total numbers of ARCMs attached on ECM, L/E and L in the ischemic group consisted of similar numbers of non-viable hypercontracted and viable rod-shaped cells. Conclusion: Cardiomyocytes should be cultured on ECM or L/E or L at concentrations from 25−200μg/ml in MMXCB. PBS is harmful to cultured ARCMs and should thus not be used as an experimental buffer. Ischemia/reperfusion can be simulated on ARCMs cultured on ECM, L/E or L from 25−200μg/ml, provided that a modified culture buffer is used as experimental buffer.
AFRIKAANSE OPSOMMING: Inleiding: Primêre selkulture van geïsoleerde volwasse rot kardiomiosiete (VRKMe) is ‘n belangrike model vir kardiovaskulêre navorsing, maar om hierdie selle suksesvol in kultuur te onderhou is ‘n groot uitdaging (Xu et al, 2009; Louch et al, 2011). Die meeste navorsingstudies maak gebruik van akuut geïsoleerde kardiomiosiete onmiddelik na isolasie omdat oorlewing van hierdie selle in kultuur baie laag is. Die struikelblokke in kultuur is as gevolg van die tipe medium en weefselkultuurgom wat gebruik word. Ons het voorheen 'n optimale medium en weefselkultuurgom geïdentifiseer vir VRKM kultuur oorlewing, maar die weefselkultuurgom was nie effektief genoeg om die selle aan die kultuuroppervlak te laat bly vaskleef, tot na die einde van 'n isgemie/herperfusie eksperiment nie. Doel: Die doel was dus om die beste weefselkultuurgom en konsentrasie te identifiseer, wat sal toelaat dat VRKMe verbonde bly aan die kultuuroppervlaktes tot na die einde van isgemie/herperfusie eksperimente. Metodes: Kardiomiosiete was geïsoleer vanaf volwasse Wistar rotharte en oornag in kultuur op verskillende konsentrasies (25 -200 μg/ml) van kollageen 1, kollageen 4, ekstrasellulêre matriks (ESM), laminin/entactin (L/E) en laminin onderhou. Die volgende dag was die VRKMe vir eksperimentasie in PBS en in PBS teenoor MMXCB gebruik, om selbehoud en oorlewing te vergelyk. Kardiomiosiete op ESM, L/E en L (25−200μg/ml) was aan 1 uur van gesimuleerde isgemie blootgestel, in MMXCB wat 3mM SDT en 10mM 2DG bevat het, gevolg deur 15 minute herperfusie. Sel oorlewing was bepaal deur selle te kleur met JC-1 en daarna was fluoressensiebeelde van die selle in ‘n veldgebied van 1.17μm/mm2 geneem. Die selle was volgens selmorfologie en fluoressensie intensiteit ontleed. Resultate: Met die gebruik van MMXCB as eksperimentele buffer in plaas van PBS, het die aantal totale en staafvormige VRKMe verbinding verbeter. Morfologiese onderhoud was sleg op kollageen 1 en 4, ongeag van watter buffer gebruik was. In kontras met die kollagene was die VRKM verbinding en morfologiese onderhoud op ESM, L/E en L in MMXCB effektief verbeter, maar in PBS aansienlik verminder. Mitochondriale lewensvatbaarheid in MMXCB teenoor PBS op kollageen 1 en 4 by 75−175μg/ml, sowel as op ECM, L/E en L by alle konsentrasies, was hoog, behalwe by 50 en 150μg/ml ESM, 175μg/ml L/E en 25μg/ml L. Isgemie blootstelling van kardiomiosiete gekultuur op alle konsentrasies van ESM, L/E en L, het ‘n afname in die totale, staafvormige en R/G fluoressensie (mitochondriale lewensvatbaarheid) teweeggebring. Meer hiperkontrakteerde kardiomiosiete was in die isgemie behandelde groepe as in die kontrole groepe teenwoordig, spesifiek op ESM by 75−150μg/ml en 200μg/ml, op L/E by 50,100μg/ml en 175μg/ml asook op L by 125μg/ml. In die isgemie groepe het die totale aantal VRKMe op ESM, L/E en L meestal uit ‘n gelyke hoeveelheid hiperkontrakteerde en staafvormige selle bestaan. Gevolgtrekking: Kardiomiosiete moet op ESM of L/E of L by konsentrasises van 25−200μg/ml in MMXCB gekultuur word. PBS is nadelig vir VRKMe in kultuur en moet dus nie gebruik word as eksperimentele buffer nie. Isgemie/herperfusie eksperimente kan gesimuleer word op VRKMe wat op 25−200μg/ml ESM, L/E of L gekultuur is, mits ‘n gemodifiseerde kultuur buffer gebruik word as eksperimentele buffer.

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Smith, Wayne. "A pathologic role for angiotensin II and endothelin-1 in cardiac remodelling and ischaemia and reperfusion injury in a rat model of the metabolic syndrome." Thesis, Link to the online version, 2006. http://hdl.handle.net/10019/1217.

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Wrightson, John M. "Pathogen identification in lower respiratory tract infection." Thesis, University of Oxford, 2014. http://ora.ox.ac.uk/objects/uuid:30c757ec-99b7-492e-a12e-ff996581863a.

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Treatment of lower respiratory tract infection (pneumonia and pleural infection) relies on the use of empirical broad spectrum antibiotics, primarily because reliable pathogen identification occurs infrequently. Another consequence of poor rates of pathogen identification is that our understanding of the microbiology of these infections is incomplete. This thesis addresses some of these issues by combining the acquisition of high quality lower respiratory tract samples, free from nasooropharyngeal contamination, with novel molecular microbiological techniques in an attempt to increase rates of pathogen identification. Four main areas are examined: (i) The role of so-called ‘atypical pneumonia’ bacteria in causing pleural infection. These pathogens have been previously identified in the pleural space infrequently and routine culture usually fails to isolate such bacteria. High sensitivity nested polymerase chain reaction (PCR) is a culture-independent technique which is used to undertake a systematic evaluation for these pathogens in pleural infection samples. (ii) The role of Pneumocystis jirovecii in pleural infection, either as a co-infecting pathogen or in monomicrobial infection. This fungus causes severe pneumonia, particularly in the immunosuppressed, but is increasingly recognised as a co-pathogen in community-acquired pneumonia, and is frequently isolated in the upper and lower respiratory tract in health. A high sensitivity real-time PCR assay is used to examine for this fungus. (iii) Ultra-deep sequencing of the 16S rRNA gene is used to perform a comprehensive microbial survey in samples taken from the multi-centre MIST2 study of pleural infection. The techniques employed allow analysis of polymicrobial samples and give very high taxonomic resolution, whilst incorporating methods to control for potential contamination. Further, these techniques provide confirmation of the results from the ‘atypical’ bacteria nested PCR study. (iv) Bedside ultrasound-guided percutaneous transthoracic needle aspiration (TNA) of consolidated lung is undertaken in patients with pneumonia, as part of the PIPAP study. An evaluation is undertaken of the efficacy and acceptability of TNA. Aspirate samples acquired are also processed using ultra-deep sequencing of the 16S rRNA gene. Other samples obtained as part of the PIPAP study, such as ‘control’ lung aspirates and ‘control’ pleural fluid samples, are similarly processed to enable calculation of sensitivity and specificity of the sequencing methodology.

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Uys, Joachim De Klerk. "The effects of early life trauma on the neurochemistry and behaviour of the adult rat." Thesis, Link to the online version, 2006. http://hdl.handle.net/10019/1249.

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Dussauge, Isabelle. "Technomedical Visions : Magnetic Resonance Imaging in 1980s Sweden." Doctoral thesis, Stockholm : Filosofi och teknikhistoria, Philosophy and the History of Technology, Kungliga Teknsika högskolan, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-4671.

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Lundkvist, Andrea, and Gabriella Norman. "A 3D Visualization of White Blood Cell Populations : A Program to Visualize Analyzed Data from a Blood Sample." Thesis, KTH, Skolan för kemi, bioteknologi och hälsa (CBH), 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-233499.

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The goal of this project was to write a program to plot populations of white blood cell types in three dimensions and reduce the information from four dimensions to three in order to make it possible to plot. The dimension reduction should be done with as little loss of information as possible. PCA, principal component analysis, was used to perform the dimension reduction. A program for this was written in MATLAB. The program that builds the plot of the populations was written in c# using Visual Studios. The visualization was made in Unity. It was possible to rotate and zoom into the plot to get a better view. The project was given by Boule Medical AB as a part of the development of a new product. Boule Medical AB only had 2D plots and requested a 3D plot in their new product. The program was handed over to Boule Medical AB for future development.

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18

Mogren, Simon. "Electromagnetic Shielding of Fine Wires for Electrophysiological Sensing." Thesis, KTH, Skolan för kemi, bioteknologi och hälsa (CBH), 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-291457.

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Tests have been performed to determine whether electromagnetic shielding of fine wires for electrophysiological sensing is a possible way to reduce the external noise in recording of nervous signals. By shielding the wires with a layer of silver, forming a coaxial cable, a reduction of the received power on the lead of 11.8-33 dBm was shown over the 10 – 10 000 Hz range when the test wire was subject to an electromagnetic field from an injection cable. When putting the performance on the interval 50-100 Hz aside the same performance was measured to 25-33 dBm lower received power, which can be explained by 50 Hz noise from the electrical grid interfering with the measurements. However, when the shield was not grounded or grounded through a resistor worse performance was shown. The difference in received power between the unshielded and shielded configuration without grounding the shield was close to 0 dBm. Following this, the type of shielding investigated in this project has the potential to substantially shield thin wires from external interference under the condition that sufficient grounding is provided.

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Ohlander, Anna. "Foil-based Lab-on-Chip technologies for advanced Point-of-Care molecular diagnostics." Doctoral thesis, KTH, Proteomik och nanobioteknologi, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-205933.

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Infectious diseases pose a serious threat to global health. Molecular diagnostics provide solutions for effective control and prevention of infections, however suffers from expensive laboratory equipment, and infrastructure to be fully implemented at point of care (POC), especially at low-resource settings. Lab-on-a-chip that aims to integrate complex biochemical analyses into automated systems is promising for POC analysis. A major challenge is the integration of a complete molecular diagnostic assay, generally translating into complex microfluidics, with the requirement of low fabrication cost. This thesis explores the use of flexible electronics, plastic foils and roll-to-roll manufacturing to enable low-cost microfluidic systems, for molecular diagnostic assays especially targeted towards infectious diseases. Many biochemical assays rely on heat; hence a first aspect in this thesis is the integration of a microheater into microfluidics. In a first project a system for SNP-genotyping is presented using solid phase melting curve analysis to discriminate mutations at a single base resolution. Starting with a glass based concept (paper I) which is further developed to a foil based system (paper II), detection of the polymorphism in the neuropeptide Y associated with increased risk of type II diabetes is demonstrated as a proof of principle. Further development and optimization of the microheater concept has enabled roll-to-roll manufacturing compatibility and multiplexing of targets (paper III). A bacterial sub-typing and multiresistance detection in clinical Staphylococcus Aureus samples is demonstrated for applications in infectious diseases diagnostics. Finally, the microheater concept is further developed to enable μPCR (paper IV). Detection of genomic HIV-1 is demonstrated and a portable detection setup based on an LED light source and low cost CMOS camera for detection was developed. A second aspect of this thesis is integration of light sources and optical detection (paper V-VI). A multilayer system integrating an electroluminescent light source, reactive sensor dyes and organic semiconductor transistor for detection is demonstrated. The system could be used for amine detection in gases (paper V). System was made further roll-to-roll compatible. The system uses an external LED light source and a photodetector processed in only one screen printing- and one dispensing step (paper VI). As a proof of principle, absorbance based DNA hybridization was detected. Collectively, roll-to-roll manufacturing compatible “lab on foil” systems have the potential to improve our ability to diagnose at POC especially at resource-limited settings.

QC 20170426

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Björneld, Olle. "Optisk instrument för Laparoskopisk Kärldetektion." Thesis, Linköpings universitet, Institutionen för medicinsk teknik, 1996. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-137478.

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Rapporten behandlar utvecklingen och konstruktionen av ett laparoskopiskt blodkärlsidentifierande instrument. Identifiering sker med hjälp av fotopletysmografi. Fotopletysmografi betyder ungefär "detektion av volymförändrings med hjälp av ljus". Laparoskopi kan översättas med titthålskirurgi. Laparoskopioperationer sker med små runda instrument som förs in i kroppen. Rapporten diskuterar olika probmodeller, det vill säga hur sensorn skall konstrueras för att erhålla en bra mätsignal. Konkurrerande tekniker och framtida applikationer redovisas på flera ställen i rapporten. Vid mätningar på blodmodell studerades och analyserades signalkvaliten. Till slut skall tilläggas att proben fungerade tillfredsställande. Proben kunde detektera pulsationer i blodmodellen.

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Janvier, Dominique. "Meditests, autotests, pratique de la biologie medicale en dehors du laboratoire." Aix-Marseille 2, 1992. http://www.theses.fr/1992AIX20907.

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CUCCHI, MICHEL, and CUCCHI MALGORZATA SZALA. "Modelisation d'une activite de biologie medicale : application a l'informatisation d'une serotheque en virologie." Lille 2, 1993. http://www.theses.fr/1993LIL2M075.

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Juma, Mahmoud. "Analys av leukocytinnehållet i framställd plasmakomponent för transfusion." Thesis, Örebro universitet, Hälsoakademin, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:oru:diva-15576.

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Mwai, Leah Wanjiru. "The activities of various antimalarial drugs on Plasmodium falciparum isolates in Kilifi Kenya and studies on mechanisms of resistance." Thesis, University of Oxford, 2011. http://ora.ox.ac.uk/objects/uuid:d90f828a-63d4-48aa-9781-3ca2de55e451.

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Drug resistance is a significant challenge in the fight against malaria. Importantly, reduced efficacy has been reported against artemether (ATM)/Lumefantrine (LM) (LM-ATM), amodiaquine (AQ)/artesunate (AS) (AQ-AS), two important combination treatment regimens in Africa, and against piperaquine (PQ), a drug which has been evaluated as a potential alternative in Africa, in combination with dihydroarteminisin (DHA). Chloroquine (CQ) resistance in P.falciparum is associated with two main transporters PfCRT and PfMDR1. I investigated the mechanisms of resistance to PQ, LM and AQ, with the overall goal of identifying molecular markers that can be used to track resistance. I used CQ as a reference. The key antimalarial drugs were highly active against clinical isolates from Kilifi, Kenya with median inhibitory concentrations (IC₅₀s) of <5nM for DHA and <55 nM for CQ, AQ, PQ, LM and DEAQ (desethylamodiaquine, the active metabolite of AQ). pfcrt-76 and pfmdr1-86 mutations were associated with AQ, DEAQ and LM but not DHA or PQ activity. Interestingly, > 20% of analysed isolates had decreased susceptibility to LM (IC₅₀ >100nM); these isolates were the most susceptible to CQ and carried wild type genotypes at pfcrt-76 and pfmdr1-86. I observed that CQ resistance had been declining in Kilifi since 1993 (prior to CQ withdrawal) to 2006 (7 years after its withdrawal), similar to observations in Malawi. My results support the hypothesis that susceptibility to antimalarial drugs returns when drug pressure is removed, and suggest that the use of LM-ATM may hasten the return of CQ susceptibility. Continued monitoring of drug susceptibility is crucial. pfcrt-76 and pfmdr1-86 may be useful molecular markers of LM-ATM efficacy in Kilifi and other African sites. Using a microarray approach, I identified additional genes (including various transporters) that may contribute to LM resistance. I recommend further studies to clarify the exact roles of the identified genes.

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Latorre, Malcolm. "The Physical Axon : Modeling, Simulation and Electrode Evaluation." Doctoral thesis, Linköpings universitet, Avdelningen för medicinsk teknik, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-138587.

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Electrodes are used in medicine for detection of biological signals and for stimulating tissue, e.g. in deep brain stimulation (DBS). For both applications, an understanding of the functioning of the electrode, and its interface and interaction with the target tissue involved is necessary. To date, there is no standardized method for medical electrode evaluation that allows transferability of acquired data. In this thesis, a physical axon (Paxon) potential generator was developed as a device to facilitate standardized comparisons of different electrodes. The Paxon generates repeatable, tuneable and physiological-like action potentials from a peripheral nerve. It consists of a testbed comprising 40 software controlled 20 μm gold wires embedded in resin, each wire mimicking a node of Ranvier. ECG surface Ag-AgCl electrodes were systematically tested with the Paxon. The results showed small variations in orientation (rotation) and position (relative to axon position) which directly impact the acquired signal. Other electrode types including DBS electrodes can also be evaluated with the Paxon. A theoretical comparison of a single cable neuronal model with an alternative established double cable neuron model was completed. The output with regards to DBS was implemented to comparing the models. These models were configured to investigate electrode stimulation activity, and in turn to assess the activation distance by DBS for changes in axon diameter (1.5-10 μm), pulse shape (rectangular biphasic and rectangular, triangular and sinus monophasic) and drive strength (1-5 V or mA). As both models present similar activation distances, sensitivity to input shape and computational time, the neuron model selection for DBS could be based on model complexity and axon diameter flexibility. An application of the in-house neuron model for multiple DBS lead designs, in a patient-specific simulation study, was completed. Assessments based on the electric field along multiple sample planes of axons support previous findings that a fixed electric field isolevel is sufficient for assessments of tissue activation distances for a predefined axon diameter and pulse width in DBS.
Elektroder används inom sjukvården, både för att mäta biologiska signaler, t.ex. hjärtats aktivitet med EKG, eller för att stimulera vävnad, t.ex. vid djup hjärnstimulering (DBS). För båda användningsområdena är det viktigt med en grundläggande förståelse av elektrodens interaktion med vävnaden. Det finns ingen standardiserad metod för att utvärdera medicinsk elektroders dataöverföringsfunktion. I den här avhandlingen presenteras en metod för att underlätta elektrodtestning. En hårdvarumodell av ett axon (Paxon) har utvecklats. Paxon kan programmeras för att efterlikna repeterbara aktionspotentialer från en perifer nerv. Längs axonet finns 40 noder, vilka var och en består av en tunn (20 μm) guldtråd inbäddad i harts och därefter kopplad till elektronik. Denna testbädd har använts för att undersöka EKG elektroders egenskaper. EKG elektroderna visade på variationer i orientering och position i relation till Paxon. Detta har en direkt inverkan på den registrerade signalen. Även andra elektrotyper kan testas i Paxon, t.ex. DBS elektroder. En teoretisk jämförelse mellan två neuronmodeller med olika komplexitet, anpassade för användning vid DBS studier, har utförts. Modellerna konfigurerades för att studera inverkan på aktiveringsavstånd från olika axondiametrar, stimulationspuls och stimulationsstyrka. Då båda modellerna visade likvärdiga aktiveringsavstånd och beräkningstid så förordas den enklare neuronmodellen för DBS simuleringar. En enklare modell kan lättare introduceras i klinisk verksamhet. Simuleringarna stöder tidigare resultat som visat att det elektriska fältet är en bra parameter för presentation av resultat vid simulering av DBS. Metoden exemplifieras vid simulering av aktiveringsavstånd och elektriska fältets utbredning för olika typer av DBS elektroder i en patient-specifik studie.

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Richter, Johan. "Fluorescence Guided Resection of Brain Tumors : Evaluation of a Hand-held Spectroscopic Probe." Doctoral thesis, Linköpings universitet, Institutionen för medicinsk teknik, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-139793.

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Malignant gliomas grow infiltrative in the brain and can therefore not be completely removed by neurosurgical means. However, for an optimized oncological treatment it has proven useful to resect as much as possible of tumor. The identification of the tumor in the marginal zone is difficult but crucial. Studies have shown that visualization of the specific enhancement of 5-aminolevulinic acid(5-ALA) in the tumor can help to maximize the resection. The Department of Biomedical Engineering, Linköping University, has developed an optical hand-held probe (HHP) to identify tumor tissue with a high sensitivity by means of fluorescence spectroscopy. The technical design and the optical properties of the probe were gradually developed in a standard neurosurgical setting during resection of malignant gliomas. The device could easily be implemented in the operating room, meeting all requirements in terms of sterile handling and without interference of any kind with other equipment. The integration of the device in a navigation system and its use in combination with a blue light surgical microscope were simple. Measurements in 27 operations during resection of malignant gliomas were compared to results from biopsies from the same tumor locations. The equipment was tested as a stand-alone device (n = 180), integrated in a navigation system or in combination with the blue light microscope (n = 190). A ratiocal culated from the measurements enabled objective and comparable values for different tissue types, in correspondence with the findings from the histopathological examinations and in accordance with the navigation system as well as with the surgical microscope.The marginal zone was explored and tumor fluorescence could be identified beyond the fluorescence as seen through the microscope. A higher sensitivity of the HHP was confirmed; the specificity was lower. The combined use of the HHP with a navigation system and with asurgical microscope was beneficial.
Maligna hjärntumörer växer infiltrerande i hjärnan och kan därförinte helt avlägsnas genom kirurgiska operationer. För en optimerad behandling har det emellertid visat sig vara av värde att avlägsna såmycket som möjligt av tumörvävnaden. Identifiering av tumören i gränszonen är mycket svårt, men avgörande. Studier har visat att visualisering av den specifika laddningen av 5-aminolevulinsyra (5-ALA) i tumören kan bidra till att maximera resektionen. Institutionen för Medicinsk Teknik (IMT) på Linköpings universitet,har utvecklat en liten handhållen optisk prob (HHP) för att identifiera tumörvävnad med hög känslighet med hjälp avfluorescens-spektroskopi. Den tekniska konstruktionen och de optiska egenskaperna hos proben utvecklades stegvis genom testning i flera neurokirurgiska operationer för resektion av maligna gliom. Utrustningen uppfyllde alla krav när det gällde steril hantering i operationssalen och kunde användas utan störningar av något slag med annan operationsutrustning. Integreringen i ett navigerings-system och användningen i kombination med ett kirurgiskt mikroskop för fluorescens-styrd kirurgi var oproblematiska. Mätningar under 27 operationer vid resektion av maligna gliom jämfördes med resultat från biopsier från samma tumörtagningsställen. Utrustningen testades såväl som en fristående enhet (n = 180) och som integrerad i ett navigationssystem eller i kombination med mikroskopet (n =190). En särskild kvot beräknad ur mätningarna möjliggjorde objektiva och jämförbara värden för olika vävnader, i överensstämmelse med resultaten från de vävnadspatologiska undersökningarna och i överensstämmelse med navigationssystemet såväl som med det kirurgiska mikroskopet. Tumörernas gränszon undersöktes och tumörfluorescens kunde identifieras bortom fluorescensen som mikroskopet visade. En högre känslighet hos HHP bekräftades; specificiteten var lägre. Den kombinerade användningen av HHP med ett navigationssystem och med ett kirurgiskt mikroskop visade sig vara fördelaktig.

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Linde, Ida, and Caroline Svedberg. "Misfit – Impact on Porcelain Fracture and Screw Loosening of Implant-supported FDPs - A Laboratory Pilot Study." Thesis, Malmö högskola, Odontologiska fakulteten (OD), 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:mau:diva-19948.

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Syfte: Syftet med denna laborativa pilotstudie var att undersöka huruvida en misfit mellan ettimplantat och en skruvretinerad bro ökade risken för sprickor och chip-off frakturer i porslinet, samt risken för uppskruvning av implantatskruvarna.Material och metod: Tjugo stycken implantatstödda skruvretinerade femledsbroar tillverkades i titan med ytporslin. Provkropparna fördelades lika mellan en testgrupp och en kontrollgrupp. I testgruppen skapades en misfit på 150 μm mellan bron och implantatet vid position 5.Provkropparna genomgick artificiellt åldrande i en cyklisk belastningsmaskin i 100 000 cykler.Synliga sprickor och chip-off frakturer noterades under och efter testet och skruvarna kontrollerades gällande uppskruvning.Resultat: Synliga sprickor i porslinet uppstod signifikant mer frekvent i testgruppen i jämförelse med kontrollgruppen. Nio broar i testgruppen uppvisade sprickor jämfört med en bro i kontrollgruppen. Tre chip-off frakturer uppstod i testgruppen jämfört med noll i kontrollgruppen, skillnaden var inte statistiskt signifikant. Vid kontroll av implantatskruvarna sågs inga signifikanta skillnader mellan varken implantatpositioner eller grupper gällande retorque-värde. Inga av skruvarna var lösa.Slutsats: Inom denna studies begränsningar tyder resultaten på att närvaron av en misfit mellan implantat och överkonstruktion kan öka risken för sprickbildning och/eller chip-off frakturer. Vidare studier krävs för att bekräfta dessa resultat.
Aim: The aim of this laboratory pilot study was to investigate whether a misfit between an implant and a FDP increase the risk of cracks, chip-off fractures and screw loosening of screw-retained implant-supported FDPs.Material and Method: Twenty screw-retained five-unit implant-supported FDPs were made intitanium with veneering porcelain. The specimens were evenly distributed into a test and control group. In the test group a misfit of 150 μm was created between the implant and FDP at position 5. All specimens underwent artificial aging in a cyclic loading machine for 100 000 cycles. Visible cracks and chip-off fractures were recorded during and after the test and the specimens were controlled for screw loosening.Results: Visible cracks within the porcelain veneer occurred significantly more often in the test group compared to the control group. Nine FDPs in the test group presented visible cracks, compared to one in the control group. Three chip-off fractures were recorded in the test group, none in the control group. This difference was not statistically significant. The retorque values of the screws presented no statistical significant differences neither between the implant positions nor the groups. None of the screws in the groups were loose.Conclusion: Within the limitations of this pilot study the results indicate that the presence of amisfit may increase the risk of cracking and/or chip-off fractures. Further studies are needed to confirm these findings.

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Qasemi, Adel, and Radhi Zayny. "The effect of preoperative brushing with chlorhexidine gel on bacterial contamination of bone transplant A clinical laboratory study." Thesis, Malmö högskola, Odontologiska fakulteten (OD), 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:mau:diva-19855.

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Introduktion: Förlust av tänder är idag vanligt förekommande och kan behandlas med hjälp av dentala implantat. För att installation av implantat ska vara möjlig, krävs tillräcklig benvolym där implantat ska installeras. När det föreligger bendefekter i anslutning till det lokala området för implantatinstallationen utgör simultaneous augmentation technique eller enstegsteknik ett behandlingsalternativ för bentransplantat. För att minimera kontamination med orala bakterier av det uppsamlade benet under beninsamlingsmetoder, används idag preoperativ sköljning med klorhexidin som ett steg i behandlingen.Syftet med denna studie är att undersöka möjligheten till ytterligare minimering av bakteriell kontamination vid implantatinstallation, med hjälp borstning av munhålan med klorhexidingel.Metod: 30 patienter deltog i en dubbelblindad, randomiserad studie där 15 patienter utgjorde en kontrollgrupp och 15 andra patienter fick genomgå den införda preoperativa tilläggsåtgärden. Ben- och paperpoint prov togs från samtliga patienter för bakteriell odling. Antalet kontaminerande bakterier uttrycktes som kolonibildande enheter (CFU/ml). En statistisk analys gjordes för att beräkna bakterieantal och kontaminationsgraden i respektive prov. Resultat: Medelvärdet för antal bakterier i benproven från samtliga patienter i kontrollgruppen beräknades till 8 126 CFU/ml respektive 2 946 CFU/ml i testgruppen dock var skillnaden inte signifikant (P = 0,357).Konklusion: Resultatet i denna studie visar ingen statistisk signifikant skillnad mellan patienter som erhållit den preoperativa profylaktiska tilläggsåtgärden, borstning med klorhexidingel, och patienter som inte erhållit detta hygiensupplement. Dessutom kunde ingen slutsats dras gällande effekten av denna tilläggsmetod på virulenta bakteriearterna P. gingivalis, P. Intermedia och A. actinomycetemcomitans. Ett större patientunderlag krävs i framtida randomiserade kontrollerade studier för att utvärdera denna metods effekt.
Introduction: Missing teeth can be replaced by dental implants. To achieve good results using dental implants, it is important that there is sufficient bone volume. In cases with bone defects, simultaneous augmentation technique becomes an alternative for bone augmentation. To minimize the contamination with oral bacteria during the bone collection, preoperative rinsing with chlorhexidine is today commonly used as a step in the treatment.The aim of this study is to examine the additional effect of preoperative brushing with chlorhexidine gel on avoiding bacterial contamination during the installation of dental implants.Method: 30 patients participated in a randomized, double blinded study. 15 patients were included in the control group and 15 patients underwent an additional step in the treatment with a preoperative brushing with chlorhexidine gel. Bone samples and paperpoint samples were collected and analyzed in a laboratory and a statistic analysis was performed to compare the number of bacterial colonies in samples from the two groups (CFU/ml) present and the degree of contamination.Results: The mean bacterial count in bone samples from all patients in the control group was calculated at 8 126 CFU/ml and 2 946 CFU/ml in the test group. CFU/ml was different between the groups (P = 0.357) but the difference was not significant (P <0.05).Conclusion: Brushing with chlorhexidine gel preoperatively showed no significant effects in the bacterial contamination of bone chips. No recommendation for adding this additional step in the standard treatment with dental implants can therefore be made today.

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Rashid, Soma, and Susann Khalil. "En studie om fem tandtekniska laboratorier i Malmö, utifrån ett arbetsmiljöperspektiv." Thesis, Malmö högskola, Odontologiska fakulteten (OD), 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:mau:diva-19773.

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Inledning: Arbetsmiljön är en viktig aspekt att ta hänsyn till för att undvika skador. Det är allt från ergonomiska skador till sjukdomar som kan förhindras genom att använda sig av rätt teknik och skyddsutrustning. En annan viktig del inom tandteknikeryrket är att laboratorierna måste ta ansvar för sina handlingar, till exempel val av material och materialhantering samt fokus på arbetstagarnas säkerhet. Slutligen för att kunna uppnå ett optimalt resultat krävs det att laboratorierna är kvalitetssäkrade. Syfte: Syftet med arbetet är att undersöka hur tandtekniska arbetsplatser ser ut, utifrån ett arbetsmiljöperspektiv.Material & metod: Intervjuerna genomfördes på tandtekniska laboratorier i Malmö genom att ha semistrukturerade intervjuer. Fem dental laboratorier medverkade i undersökningen, var vid respektive laboratoriechefer och skyddsombud intervjuades.Resultat:Studien påvisade medvetna laboratoriechefer/skyddsombud som hade planer på hur de skulle gå tillväga för att uppnå ett bra resultat med gynnsamma arbetsmiljöförhållande. Fyra av fem respondenter konstaterade att arbetstagarna är medvetna om riskerna som kan uppstå på arbetsplatsen.Slutsats:Slutsatserna som kan dras med beaktande av studiens begränsningar är att:•Intervjuerna visade att respondenterna är medvetna om hur en optimal verksamhet kan uppnås utifrån ett arbetsmiljöperspektiv. Dock tas inte alltid ställning till det på grund av bland annat brist på resurser.•Studien visade att mätningar på ventilation och utsug utförs regelbundet för att säkerställa att allt är under kontroll.
Introduction: The work environment is an important aspect to consider in order to avoid damage. One way to prevent injuries, diseases and poor ergonomics is by using protective equipment that are provided for such things. Another important part of the dental technician profession is that laboratories must take responsibilities for their actions. They need to consider the right use of materials and how to handle them correctly. The laboratory must also focus on the employee’s safety. At last, in order to achieve an optimal result, it is required that laboratories are quality assured.Aim: The aim of this study is to investigate how a dental laboratory looks from a work environment perspectiveMaterial and method: The semi-structed interviews were held in dental laboratories in Malmö. Five dental laboratories participated in the survey in which laboratory manager/safety representative were interviewed.Results: The study showed positive results and awareness among laboratory managers/safety representatives that have knowledge of how to achieve favorable working conditions. Four out of five respondents established that the employees are aware of the risks that may occur in the workplace.Conclusion: Within the scope of the study, the following conclusions can be drawn:• The interviews showed that the respondents are aware of how to achieve an optimal work environment, but they do not always have the resources to do so. • The study showed that measurements of ventilation and suction are performed regularly to ensure that everything is under control.

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Boltshauser, Rasmus. "Development of a Novel Device for Optimal Sample Blood Volume Collection from Patients with Sepsis." Thesis, KTH, Medicinteknik och hälsosystem, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-279133.

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When performing sepsis diagnosis, the most important preanalytical variable is blood volume. Too little blood increases the risk for false negatives whereas overfilling causes increased risk for false positives. Even though this fact is known, there are case studies showing that in a majority of tests, the taken blood sample volume is not the recommended amount. As previously tried methods have been limited in their ability to tackle the problem this study aimed at creating a technical device to aid healthcare providers with blood volume sample collection. As a base, the double diamond approach by the Design Council was used. This design approach splits up the design process in four distinctly different phases (discover, define, develop, and deliver) all using their own methods to aid the creative process. After completing the discover and define phase it was determined that a non-contact capacitance liquid level sensor could operate as an ideal blood volume sample device. During the development and delivery phase prototypes were created and evaluated. The final results of this work could not give conclusive evidence concerning if a non-contact liquid level sensor could operate as an ideal blood volume collection device. The methodological approach used in this thesis can be used as inspiration for a designer to create a device for a similar or different purpose. Moreover, information from this thesis can also work as reference material to develop a device to perform ideal blood volume sample collection. Such a device would have the potential to be an essential part of the everyday workflow in sample collection from patients with sepsis worldwide and would aid in ensures effective and fast diagnostics.

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Arokoyo, Dennis Seyi. "Antidiabetic and profertility mechanisms of aqueous extract of Basella alba in male Wistar rats." Thesis, Cape Peninsula University of Technology, 2017. http://hdl.handle.net/20.500.11838/2736.

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Thesis (PhD (Biomedical Sciences))--Cape Peninsula University of Technology, 2017.
The use of medicinal plants in the management of various health problems date back to the ancient times. However, only in recent years, researchers are starting to focus on the use of natural plant products as alternative treatment in disease control. Basella alba (Ba), commonly called Ceylon or Indian spinach is one of such medicinal plants, wildly cultivated and consumed mostly as vegetable. Studies have established many beneficial effects of Ba, including androgenic effects as well as antidiabetic effects which have been described in rats following oral administration of the leave extract. However, the actual mechanisms underlying the antihyperglyceamic effect of Ba have not been reported in any study and little or no research details are yet available on the potential beneficial effects of Ba in reproductive dysfunction resulting from diabetes mellitus. This study was aimed at investigating the mechanisms underlying the antidiabetic effect of Ba and the possibility of a role for the plant in correcting diabetic-induced reproductive dysfunctions in male Wistar rats. The first part of the study involved comparing of three different solvent extracts of Ba leaves namely ethyl acetate, methanolic and aqueous extracts for their antioxidant potentials, after which the aqueous extract was selected for further use in the experiments. Animal experimentation involved male rats (n=40) aged 8-10 weeks, randomly divided into four equal groups as follows: Healthy Control, Diabetic Control, Healthy Treatment and Diabetic Treatment. Diabetes was induced via a single intraperitoneal injection of streptozotocin (55mg/kg) and all animals subsequently received treatment via gavage (Rats in Control groups received 0.5ml/100g normal saline daily and treatment groups received 200mg/kg plant extract daily) for a period of four weeks. Fasting blood sugar and body weights were recorded weekly throughout the study. Animals were sacrificed upon completion of the treatment and blood samples and tissues collected for further analysis which included computer aided sperm analysis, Luminex® technology and enzyme-linked immunosorbent hormonal assays, inflammatory cytokine assays, analysis of oxidative stress markers and Histopathological analysis. The single intraperitoneal injection of a high streptozotocin dose resulted in hyperglycaemia, weight loss, subnormal sperm parameters, negative balance of inflammatory cytokines and endogenous antioxidants and degenerative changes in the pancreas, testes and epididymis as observed in the diabetic control rats. Oral administration with the aqueous extract of Ba for four weeks in diabetic treatment rats led to a significant reduction in blood sugar and improvement of sperm parameters by modulating the production of gonadal hormones, in vivo antioxidants and inflammatory cytokines. There was also significant recovery of normal islet histology and reduction in testicular and epididymal degeneration in the diabetic treatment rats when compared to their diabetic control counterparts. It was concluded from the findings of this study that the antidiabetic and profertility effects of Ba are largely dependent on the modulation of in vivo production of antioxidants, gonadal hormones and inflammatory cytokines, probably stimulated by one or more phytochemical component(s) that can be isolated in the aqueous extract of the plant.

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Lourenço, Patrick Menezes. "Erros pré-analíticos em medicina laboratorial: uma revisão sistemática." Universidade do Estado do Rio de Janeiro, 2013. http://www.bdtd.uerj.br/tde_busca/arquivo.php?codArquivo=8244.

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MENEZES, Patrick Lourenço. Erros pré-analíticos em medicina laboratorial: uma revisão sistemática. 2013. 98 f. Dissertação (Mestrado em Saúde, Medicina Laboratorial e Tecnologia Forense) - Instituto de Biologia Roberto Alcântara Gomes, Universidade do Estado do Rio de Janeiro, Rio de Janeiro, 2013. A relevância evidente dos erros pré-analíticos como problema de saúde pública fica patente tanto no dano potencial aos pacientes quanto nos custos ao sistema de saúde, ambos desnecessários e evitáveis. Alguns estudos apontam que a fase pré-analítica é a mais vulnerável a erros, sendo responsável por, aproximadamente, 60 a 90% dos erros laboratoriais em consequência da falta orientação aos pacientes sobre os procedimentos que serão realizados no laboratório clínico. Objetivos: Sistematizar as evidências científicas relacionadas aos erros pré-analíticos dos exames laboratoriais de análises clínicas. Método: Uma revisão sistemática foi realizada, buscando as bases de dados do Medical Literature Analysis and Retrieval System Online (MEDLINE), Scopus(que inclui MEDLINE e Embase), ISI Web of Knowledge, SciFinder, Literatura Latino-Americana e do Caribe em Ciências da Saúde (Lilacs) (que inclui a Scientific Electronic Library Online SciELO) e o Índice Bibliográfico Espanhol de Ciências de Saúde (IBECS), para artigos publicados entre janeiro de 1990 e junho de 2012 sobre erros de exames laboratoriais que possam ocorrer na fase pré-analítica. Os estudos foram incluídos de acordo com os seguintes exames laboratoriais: hemograma, análise bioquímica do sangue total ou do soro, exames de coagulação sanguínea,uroanálise e exames hematológicos ou bioquímicos em outros materiais e categorizados pelo tipo de erro pré-analítico e pela frequência dos incidentes. Resultados: A busca nas bases de dados bibliográficas resultou no seguinte número de artigos recuperados: 547 na MEDLINE, 229 na Scopus, 110 na ISI, 163 na SciFinder, 228 na Lilacs e 64 na IBECS, perfazendo um total de 1.341 títulos. Ao fim da revisão sistemática, obteve-se um conjunto de 83 artigos para leitura de texto completo, dos quais 14 foram incluídos na revisão. Os estudos abrangeram diferentes tipos de laboratórios, setores técnicos e origem de erros, segundo a fase do processo laboratorial. Discussão: Sete artigos demonstraram erros de pedidos médicos, com uma alta variabilidade nos valores de incidência. Os seis artigos que estudaram erros de coleta de amostra observaram redução deste desfecho. As proporções de eventos adversos relatados e os impactos clínicos variaram, levando a consequências descritas como: erros decorrentes da flebotomia, recoleta de amostras, repetições de exames, atrasos na liberação de resultados de exames e possíveis danos ao paciente. Conclusões: O laboratório deve ter instruções por escrito para cada teste, que descreva o tipo de amostra e procedimento de coleta de amostra. Meios de identificação por código de barras, sistemas robóticos e analíticos reduzem os erros pré-analíticos. A melhoria da fase pré-analítica de testes laboratoriais permanece um desafio para muitos laboratórios clínicos.
The obvious relevance of preanalytical errors as a public health problem is clear in both the potential harm to patients and cost to the health system, both unnecessary and avoidable. Some studies indicate that the pre-analytical phase is the most vulnerable to errors, accounting for approximately 60-90% of laboratory errors as a result of lack guidance to patients about the procedures to be performed in the clinical laboratory. Objectives: To systematize the scientific evidence related to preanalytical errors of clinical analysis laboratory. Method: A systematic review was conducted, searching the databases of the Medical Literature Analysis and Retrieval System Online (MEDLINE) , Scopus (which includes MEDLINE and Embase ), ISI Web of Knowledge , SciFinder , Latin American and Caribbean Health Sciences (LILACS) ( which includes the Scientific Electronic Library Online - SciELO) and the Spanish Bibliographic Index of Health Sciences (IBECS) for articles published between January 1990 and June 2012 on laboratory errors that may occur in the preanalytical phase. Studies were included according to the following laboratory tests: complete blood count, biochemical analysis of whole blood or serum, blood coagulation tests, urinalysis and hematological or biochemical analysis of other materials categorized by the type of pre - analytical error and the frequency of incidents. Results: The search in bibliographic databases resulted in the following number of items retrieved: 547 in MEDLINE, Scopus at 229, 110 in the ISI in SciFinder 163, 228 and 64 in the Lilacs IBECS, a total of 1.341 titles. At the end of the systematic review, we obtained a set of 83 articles for reading the full text, of which 14 were included in the review. The studies covered different types of laboratories, technical sectors and source of errors, according to the phase of the laboratory process. Discussion: Seven articles showed errors in the medical requisition, with a high variability in the incidence values. The six articles that studied sample collection errors observed reduction in this outcome. The proportions of reported adverse events and clinical impacts varied, leading to consequences described as: errors resulting from phlebotomy, recollection of samples, repetition of exams, delays in the release of the test results and possible harm to the patient. Conclusions: The laboratory must have written instructions for each test, which describes the type of sample and collection procedure. Identification methods by barcode, robotic and analytical systems, reduce preanalytical errors. The improvement of pre-analytical phase of laboratory tests remains a challenge for many clinical laboratories.

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Berglin, Ewa. "Predictors of disease onset and progression in early rheumatoid arthritis : A clinical, laboratory and radiological study." Doctoral thesis, Umeå : Public Health and Clinical Medicine, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-669.

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Tovedal, Tobias. "Tactile resonance method for measuring stiffness in soft tissue - evaluation of piezoelectric elements and impression depth using a silicone model." Thesis, Umeå universitet, Institutionen för fysik, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-137114.

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An instrument is being developed at the Department of Biomedical Engineering; Research and Development (MT-FoU), at the University Hospital of Umeå with the aim to detect prostate cancer ex vivo. Using a combination of tactile resonance technology and Raman spectroscopy the instrument is intended to be used in the operating room during radical prostatectomy to identify positive surgical margins. The hypothesis was that the length of the piezoelectric element used in the tactile resonance sensor affects the sensor's sensitivity and reproducibility when measuring the stiffness of soft tissue, and that there might be an optimal impression depth to measure at. The specific aim of this study was to evaluate two piezoelectric elements, of different lengths, by the sensitivity and reproducibility of the measurements they performed. Measurements were performed on five silicone samples of different stiffness, during a 2 mm impression. The standard deviation of the stiffness parameters, the R2 of the linear regression used to determine the stiffness parameter, and the depth at the which the most linear relationship between impression force and frequency shift was found were studied using linear mixed-effects models to identify any significant differences between the elements. The long element had a significantly higher R2 of 0.98 compared to 0.93 for the short element, and a higher measurement depth of 0.47 mm compared to 0.37 mm for the short element. No difference between the elements were found on accuracy as measured by standard deviation of the stiffness parameter. It was concluded that this was not enough to claim that one element was better than the other.
Ett instrument utvecklas på avdelningen för Medicinsk teknik, forskning och utveckling, vid Norrlands universitetssjukhus med målet att detektera prostatacancer ex vivo. Instrumentet kombinerar taktil resonansteknologi med Ramanspektroskopi och är tänkt att användas i operationssalen under radikal prostatektomi för att identifiera positiv kirurgisk marginal. Hypotesen var att längden av det piezoleketriska element som används i den taktila resonanssensorn påverkar sensorns känslighet och reproducerbarhet vid mätning av styvhet av mjukvävnad, och att det kan finnas ett optimalt intryckningsdjup att mäta på. Målet med denna studie var att utvärdera två piezoelektriska element, av olika längd, utifrån känsligheten och reproducerbarheten av mätningarna de utförde. Mätningarna gjordes på fem silikonsprover av olika styvhet, under 2 mm intryckning. Standardavvikelsen av styvhetsparametern, R2 av den linjära regression som användes för att bestämma styvhetsparametern, samt det intryckningsdjup på vilket det mest linjära förhållandet mellan intryckningskraft och frekvensskift hittades, studerade med så kallade linear mixed-effects modeller för att identifiera signifikanta skillnader mellan elementen. Det långa elementet hade ett signifikant högre R2 på 0.98 jämfört med det korta elementets 0.93, och ett högre mätdjup på 0.47 mm jämfört med det korta elementets 0.37 mm. Ingen skillnad mellan elementens standardavvikelser av styvhetsparametern hittades. Slutsatsen drogs att resultatet inte var nog för att påstå att det ena elementet är bättre än det andra.

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Björkman, Simon. "Utveckling och optimering av en multiplex-PCR screen för högfrekventa humana trombocytantigen (HPA) alleler -1a, -2a, -3a, -5a, -15a och -15b med Extract-N-Amp Blood kit." Thesis, Högskolan Kristianstad, Sektionen för lärande och miljö, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:hkr:diva-16993.

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Det är känt att humant trombocytantigen (HPA) kan innebära komplikationer vid transfusion av trombocyter. Om en patient erhåller trombocyter med humant trombocytantigen som personen redan utvecklat antikroppar emot kan komplikationer som feber, påskyndad nedbrytning av trombocyter som ger trombocytopeni samt post-transfusion purpura uppstå eftersom immunförsvaret då ser trombocyterna som fientliga. Från den 14:e veckan under graviditeten kan alloantikroppar från modern passera placentabarriären över till fostret. Om humant trombocytantigen skiljer mellan moder och foster kan modern utveckla antikroppar. Dessa antikroppar kan då förstöra fostrets trombocyter. Detta leder till en lägre koncentration av trombocyter hos barnet. I värsta fall kan detta leda till hjärnblödning med dödlighet på ca.20%. Om barnet överlever födseln kommer denne födas med fetal/neonatal alloimmuniserad trombocytopeni (FNAIT), d.v.s. medfödd trombocytopeni. Målet med denna studie var att utveckla en multiplex PCR-screen, snabbt positivt/negativt svar för högfrekventa Humant trombocytantigen alleler baserat på de mest frekventa som förekommer i dansk befolkning: HPA 1a, -2a, -3a, -5a, -15a och -15b med Extract-N-AmpTMblood kit. Negativa prov från screening genomgick allelic discrimination real-tids PCR för konfirmering av sann HPA- genotyp. En lyckad multiplex screenmix innehållande HPA 1a, -2a, -5a samt -15a genomfördes. Då HPA - 3a bildade ospecifika band fick denna plockas bort ur mixen. För HPA 15b bildades ingen PCR- produkt och kunde därför inte inkluderas. Totalt screenades 44 blodgivare från Region Skåne varav fyra var negativa för 15a. Detta konfirmerades med allelic discrimination där dessa genotypades till 15b och i likhet med den multipla screeningen inte visade amplifiering av 15a. Vidare optimering krävs där nya primers för 3a samt 15b måste designas för att skapa en komplett högfrekvent human trombocytantigen screen.

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Lundin, Anna-Carin. "Tendinosis in Trigger Finger." Doctoral thesis, Linköpings universitet, Avdelningen för Kirurgi, Ortopedi och Onkologi, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-136784.

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Trigger finger is one of the most common hand conditions, with a prevalence of almost 3%. The aetiology remains unclear even though many causes have been suggested. The prevailing paradigm is that the pathogenesis of trigger finger is ascribed to primary changes in the first fibrous condensation of the tendon sheath (A1-pulley). Several studies have investigated pathology in the pulley, but few have investigated the tendon. The general aim of this thesis was to find out if there is pathology in the trigger finger tendon and to define it. We first looked at trigger finger tendon biopsies in a light microscope, and found that they were histologically different from healthy tendons. They showed signs of micro-ruptures, collagen degradation, increased amounts of ground substance, both hyper- and hypo-cellular areas, round active cell nuclei and absence of inflammatory cells, all similar to tendinosis. The histological picture was further assessed by using a scoring system for Achilles tendinosis. The trigger finger tendons scored high, suggesting a similar histopathology. Next, we performed a quantitative real-time polymerase chain reaction (qPCR) on trigger finger tendons. We assessed the mRNA expression of 10 genes, which have been described to be differently expressed in Achilles tendinosis (collagen 1 and 3, versican, decorin, biglycan, aggrecan, MMP-2, MMP-3, ADAMTS-5, and TIMP-3). The overall expression pattern agreed with previous studies on Achilles tendinosis, suggesting that the cellular function in trigger finger tendons is disturbed in a similar way as in Achilles tendinosis. Recent experimental and observational research has suggested potential side effects of statin treatment on tendons, but firm evidence was lacking. We performed an epidemiological study on two large population-based cohorts. Statin use was found to increase the risk of both trigger finger and tendinosis in the shoulder and Achilles tendons, especially among men. This suggests a similar pathology in trigger finger and tendinosis. We have also studied the time to treatment effect after a single injection of glucocorticoid in trigger finger. Our results suggest that 60-80% of patients can expect resolution of the triggering within 14 days, and half of them within seven days. This result allows correct information to be given to the patient and proper planning of follow-ups. In conclusion, the pathology in trigger finger tendons is similar to tendinosis in other tendons.

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Svensson, Adrian. "En jämförelse av olika covid-19 vaccin." Thesis, Malmö universitet, Fakulteten för hälsa och samhälle (HS), 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:mau:diva-44521.

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Bakgrund: I slutet av 2019 upptäcktes flertalet fall av pneumoni av okänd etiologi i Wuhan, Kina. Efter isolering och sekvensering framkom det att det rörde sig om ett coronavirus, benämnt SARS-CoV-2. Sociala restriktioner och munskydd har inte lyckats stoppa denna pandemi, och hoppet ligger nu på de olika vaccinkandidater som började utvecklas under 2020. Syfte: Syftet var att jämföra olika vaccins effektivitet och förekomst av olika biverkningar. Metod: En systemisk litteraturstudie utfördes, där en sökning i Pubmed utfördes och fyra artiklar valdes ut till arbetet för att jämföra vaccineffektivitet och biverkningar för de tre vaccin som var godkända av läkemedelsverket i februari. Resultat: Pfizer/BioNTechs mRNA-vaccin hade en effektivitet på 94,8%, Modernas mRNA-vaccin en effektivitet på 94,1% och Oxford-AstraZenecas vektorvaccin uppvisade en effektivitet på 70,4%. De vanligaste biverkningarna vid vaccinering var smärta vid injektionsplatsen, huvudvärk samt utmattning. Slutsats: En tillfredsställande jämförelse kunde inte genomföras då de olika fas III studierna utfördes på olika åldersgrupper och i olika delar av världen där SARS-CoV-2 mutationerna skiljde sig åt, vilket kan ha påverkat resultaten.
Background: At the end of 2019, several cases of pneumonia of unknown ethology were discovered in Wuhan, China. After isolating and sequencing the pathogen it became apparent that it was a Coronavirus, named SARS-CoV-2. Social restrictions and mask wearing mandates have not managed to stop this pandemic, and the hope lies with the different vaccine candidates that started to be developed during 2020. Aim: The aim was to compare different vaccines efficacy and prevalence of side effects. Method: A systemic literature study was implemented, the search was done in Pubmed and four papers were selected to compare vaccine efficacy and side effects for the three vaccines that were approved by Läkemedelsverket in February. Results: Pfizer/BioNTech’s mRNA-vaccine showed an efficacy of 94,8%, Moderna’s an efficacy of 94,1% and Oxford-AstraZeneca’s vector vaccine showed an efficacy of 70,4%. The most common side effects following vaccination was pain at the site of injection, headache and fatigue. Conclusion: A satisfying comparison could not be achieved since the different phase III studies were performed on different age groups and in different parts of the world where SARS-CoV-2 mutations differ, which could impact the results.

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38

Strada, Carlo. "Measuring and Processing Biogas Produced in Laboratory-Scale Batch Reactors." Doctoral thesis, Università degli studi di Bergamo, 2017. http://hdl.handle.net/10446/77382.

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In this work the upgrading of biogas into biomethane has been addressed by resorting to the use of the chemical capture of carbon dioxide. We started with the realization of a biodigestion systems used as source of biogas. With this system, we investigated either the production capacity of the different substrates and the main factors (temperature, pH and mixing of the substrate) which influence the biodigestion process. To make accurate measurements of the amount of biogas and biomethane produced, three types of different gas-meters, all based on the principle of liquid displacement, have been devised, assembled and compared. We have also evaluated three different types of gas flow calibrators, based on the principle of thermal mass flow sensing, constant differential pressure and mechanical displacement. At the end, we used the systems built to investigate the capture of carbon dioxide by ammonia in aqueous solution at room temperature and pressure where the volatilization of the ammonia has been limited by non-traditional methods.

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39

Yang, Jing. "Determination of peramivir and its toxicokinetics in beagle dogs." Thesis, University of Macau, 2011. http://umaclib3.umac.mo/record=b2524966.

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40

Marescaux, Laurent. "Etude en irm du remodelage ventriculaire post-infarctus chez le rat (doctorat : imagerie medicale)." Angers, 1999. http://www.theses.fr/1999ANGE0509.

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41

Goboza, Mediline. "The biochemical effects of Hypoxis hemerocallidea in the kidney and liver of streptozotocin-induced diabetic male Wistar rats." Thesis, Cape Peninisula University of Technology, 2015. http://hdl.handle.net/20.500.11838/2233.

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Thesis (MTech (Biomedical Technology))--Cape Peninsula University of Technology, 2015.
Diabetes mellitus (DM) is an endocrine disorder that is characterised not only by severe hyperglycemia but also altered metabolism of glucose and lipids. It is a major health problem worldwide and its impact is greatly noticed in developing countries due to the lack of adequate medical facilities. Oxidative stress remains the principal factor that actively plays major roles in the onset and progression of diabetes mellitus and its complications. The use of medicinal plants in the treatment of DM has undisputedly gained the attention and interest of researchers throughout the globe mainly because plants have established promising outcomes in the treatment of diabetes. It is evident that the plants’ constituents possess therapeutically potent metabolites that have beneficial effects such as antioxidant, antidiabetic, anticancer, anti-inflammatory and antibacterial activities. Hypoxis hemerocallidea is a native plant that grows in the Southern African regions. H. hemerocallidea is well known for its beneficial medicinal values. In South Africa it is known as the African potato. The main aim of this study was to investigate both the beneficial and also the possible toxic effects of H. hemerocallidea in the kidney and liver tissues of streptozotocin-induced diabetic male Wistar rats by assessing the antioxidant status and selected biochemical parameters in the two studied organs. Diabetes was induced in overnight fasted rats by administration of a single intraperitoneal injection of STZ at a dosage of 50mg/kg in citrate buffer (0.1 M at 4.5 pH). Hyperglycemia was confirmed 72 hours after induction of diabetes using STZ in rats with glucose levels > 15 mmol/l. Treatment with the plants extract commenced on the fourth day after STZ administration via gastric gavage that was done once a day over a 6 week period. The effects of H. hemerocallidea on glucose, body weight, liver and kidney weights, liver function, kidney function and the oxidative status were evaluated after the feeding period.

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42

Filipsson, Emma, and Cecilia Olsson. "Interobserver variability when measuring the abdominal aorta with ultrasound : A comparison using the longitudinal and transverse axes." Thesis, Hälsohögskolan, Högskolan i Jönköping, HHJ, Avd. för naturvetenskap och biomedicin, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:hj:diva-40563.

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A rupturing abdominal aortic aneurysm (AAA) has a mortality rate of 50% while an elective repair has a mortality rate of 3-8%. Screening programmes with ultrasound are used in some countries to detect AAA at an early stage. Ultrasound is however very observer bias and dependent on the observer's experience. The study was performed in Vietnam, a country that have experienced exceptional economic growth with increasing risk factors for cardiovascular diseases but has no national screening programme. The aim of this study was to examine the interobserver variability when measuring the abdominal aorta with ultrasound on young adults in Vietnam. The abdominal aorta was measured in the longitudinal and the transverse axis by two different observers using the leading edge to leading edge method. Participants in this study were 31 voluntary students, 16 men and 15 women in the ages 18-26 years, from the Da Nang university of medical technology and pharmacy and the design was a cross-sectional study with a quantitative approach. The study showed a significant difference between the longitudinal measurements but not between the transverse measurements. Despite this statistical significance, the observers' differences were within the recommended limit of 5 mm.
Ett rupturerande bukaortaaneurysm har en dödlighet på 50% medan förebyggande vaskulär kirurgi har en dödlighet på 3-8%. Screeingprogram med ultraljud används i vissa länder för att upptäcka bukaortaaneurysm i ett tidigt skede innan de rupterar. Ultraljudsundersökningen är dock väldigt beroende på utövarens erfarenhet och utbildning. Studien genomfördes i Vietnam, ett land som genomgått stor ekonomisk tillväxt men även en ökning av riskfaktorer för kardiovaskulära sjukdomar. Vietnam har dock inget nationellt screeningprogram för bukaortaaneurysm. Syftet med studien var att undersöka observatörsvariationen vid mätning av bukaortan med ultraljud på unga vuxna i Vietnam. Populationen var ung för att minska patologiska fynd. Bukaortan mättes med metoden leading edge to leading edge, både i det longitudinella och i det transversella snittet av två olika utövare. Observatörerna var två studenter från Biomedicinska analytikerprogrammet med inriktning klinisk fysiologi, Jönköpings Universitet. Deltagare i studien var 31 frivilliga studenter, 16 män och 15 kvinnor i åldrarna 18-26 år, från Da Nang University of medical technology and pharmacy och designen var en tvärsnittsstudie med kvantitativ ansats. Studien visade en signifikant skillnad i de longitudinella mätningarna men inte i de transversella mätningarna. Trots denna statistiska signifikans var observatörernas differenser inom den rekommenderade gränsen på 5 mm.

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43

Maglio, Rosetta, and Julia Osswald. "Utredning av Genius 2-termometrar på Södersjukhusets vuxenakut." Thesis, KTH, Medicinteknik och hälsosystem, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-298437.

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Arbetet utfördes på Södersjukhusets vuxenakut och utredde avdelningens tympaniska termometrar. Det finns två sorters tympaniska termometrar på vuxenakuten, Genius 2 från Philips och ThermoScan PRO 6000 från Braun. Genius 2 är uppkopplad till patientövervakningssystemet IntelliVue och ThermoScan PRO 6000 är mobil. Arbetet utfördes på förfrågan av Södersjukhuset då personalen på vuxenakuten var missnöjda med Genius 2-termometrarna, detta på grund av att de inte ansågs vara tillförlitliga. Arbetet ämnade att utreda orsaken till Genius 2-termometrarnas höga mätosäkerhet samt vad den generella bilden av termometern var hos personalen. För att undersöka Genius 2-termometrarna och orsakerna till problematiken på vuxenakuten utfördes fyra olika moment. Utredningens första del började med intervjuer av vuxenakutens sjuksköterskor och undersköterskor. Målet med intervjuerna var att få en bild av problemet från personalens perspektiv för att sedan kunna undersöka problematiken med hjälp av kalibreringar och två termometertest. Del två av undersökningen gick ut på att kalibrera termometrarna för att säkerställa att de termometrar som deltog i termometertesten fungerade på ett korrekt sätt. Den tredje delen gick ut på att utföra två termometertest. Målet med det första termometertestet var att utreda variationen inom och mellan termometrarna Genius 2 och ThermoScanPRO 6000. I detta test var försökspersonerna och användarna densamma och termometrarna varierades. Målet med det andra termometertestet var att undersöka huruvida handhavandet påverkade mätvärdena. I detta test var försökspersonerna, en Genius 2-termometer och en ThermoScan PRO 6000-termometer densamma medan användaren varierades. Den sista delen av undersökningen gick ut på att utreda huruvida kalibreringen av Genius 2-termometrarna var hållbara ur ett tidsperspektiv. Termometrarna som en månad tidigare hade kalibrerats och fått ett godkänt resultat kalibrerades därför igen. Detta för att undersöka vilka termometrar som fortfarande fick ett godkänt resultat. Resultatet påvisade att Genius 2-termometrarna har mycket större variation både inom och mellan termometrarna jämfört med ThermoScan PRO 6000. Variationen var dock inte så stor att det påverkade patientsäkerheten. Resultatet visade även att handhavandet påverkade mätvärdena och att delar av personalen utförde temperaturmätningar på ett mer komfortabelt sätt för patienten, detta gav också mätvärden som ansågs vara mer korrekta. Från resultatet framkom det att 20 % av termometrarna som tidigare hade klarat kalibreringen fick ett underkänt resultat när kalibreringen kontrollerades en månad senare. Detta innebär att Genius 2-termometern inte uppfyller de krav som finns för att säkerställa att den kan fungera på ett korrekt sätt. Tidigare nämnda resultat medför att personalen på vuxenakuten får arbeta med utrustning som inte lever upp till de förväntningar och krav som finns. Detta medför ineffektivitet, dubbelarbete och en minskad tillförlitlighet för Genius 2-termometern. Alla termometrar som fanns på vuxenakuten deltog inte i testerna och därför finns det behov av att vidare undersöka detta problem.
The investigation was done at Södersjukhuset’s emergency department where two types of tympanic thermometers were investigated. Genius 2 from Philips, which is connected to a patient monitor called IntelliVue and ThermoScan PRO 6000 from Braun, which is mobile. The investigation was done at the request of Södersjukhuset because the staff at the emergency department considered Genius 2 not to be reliable. The intent of the investigation was to determine the cause of Genius 2’s measurement uncertainty and to understand what the general opinion of the thermometer is among the employees. The investigation began with interviews with nurses and assistant nurses. The goal was to get the general opinion and thereafter investigate the problems using calibrations and thermometer tests. After the interviews, all thermometers that were intended for the tests were calibrated. The calibrations were done to ensure that only working thermometers were included in the tests. The first thermometer test was intended to investigate the variation within and between the Genius 2 and ThermoScan PRO 6000 thermometers. The subjects and the users were constant while the thermometers were varied. The second thermometer test was intended to investigate whether the handling of the thermometers affected the measured values. In this test, the subjects, a Genius 2 thermometer and a ThermoScan PRO 6000 thermometer stayed the same while the user was varied. The last part of the investigation was intended to investigate whether the calibration of the Genius 2 thermometers was consistent after one month. The results showed that Genius 2 had greater variation within and between the thermometers, compared to ThermoScan PRO 6000. However, the variation was not so great that it affects patient safety. The results also showed that the handling of the thermometers affects the results and that part of the staff were able to execute the temperature measurements in a more comfortable way for the patient. This gave measured values that were considered to be more accurate. The results showed that 20% of the thermometers that had previously undergone calibration failed when the calibration was redone a month later. This means that the Genius 2 thermometer does not meet the existing requirements to ensure that it functions properly. Not all thermometers were included in the investigation which is why our recommendation is to further investigate the problems.

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44

Bagge, Joakim. "Chromatography of Therapeutic Peptides - Contrasting SFC and HPLC." Thesis, Uppsala universitet, Farmakognosi, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-390890.

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This work is a comparison of a well-established and a novel, "green" and efficient technique to separate peptides of pharmaceutical interest. An attempt is made to derive the chromatographic retention behaviour from these techniques to a number of property descriptors derived from the linear sequence of amino acids. A set of therapeutic peptides were carefully chosen to be experimentally evaluated using in silico-based descriptor calculations. A principle component analysis was performed to assess the distribution of calculated descriptors for including peptides with variable properties. A diluent optimization study was also included to find the optimal diluent for peptides with minimal diluent effects and peak splitting phenomena. The results showed that the solvents tert-butanol and methanol performed best between 20-30 and 50 volumetric percent water as additive in SFC and HPLC, respectively. These diluents were then used for the peptides within the set to evaluate the retention and selectivity in HPLC and SFC. SFC performed well in terms of resolving power. Inparticular, SFC was able to separate Leuprolide and Triptorelin while HPLC was not. A comparison was also made in between the two stationary phases CN and XT, where a global selectivity was shown to be higher for CN. This work does also assess a novel method for determining solubility of analytes in supercritical fluid. The method was evaluated using the pharmaceutical compounds caffeine and aspirin and then used to determine solubility of Leu-Enkephalin in 20% (v/v%) methanol. The solubility of caffeine was determined to be 0.45 mg ml-1 in pure SF-CO2 under 140 bar pressure and 3.9 mg ml-1 for aspirin in 2.4% methanol. Both values correlated well with measurements from four acknowledged papers within this field. Leu-Enkephalin was found to have a solubility of 1.90 mg ml-1 using a solvent corresponding to the initial phase condition of the gradient used for peptide analysis in SFC. Further experimental work is required before the method can be implemented as a useful tool in preparative chromatography, however the results presented here show the compatibility of assessing biomolecules in both pure SF-CO2 and mixed with modifier. The possibility to determine solubility with additional modifier infers an important step of including and evaluating these compounds creating a solid support to subsequent large scale separation.

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45

Buglass, Surahanil Katrin. "Regulating stem cell fate within microenvironmental niches." Thesis, University of Oxford, 2014. http://ora.ox.ac.uk/objects/uuid:75f9498c-30f0-4983-84b2-dd58f2ccf52b.

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Improving the repopulation potential of human umbilical cord blood (UCB) haemopoietic stem cells (HSCs) remains a paramount goal in HSC transplantation (HSCT) therapy. This implies enhancing the homing and engraftment potential of UCB-CD34+CD133+ cells to the bone marrow (BM). Although an array of molecules continues to be identified as ‘key’ homing molecules, the molecular mechanisms controlling HSC homing are still not fully understood. The regulatory implications of hypoxia in the BM, with the concomitant stabilisation of hypoxia inducible transcription factor-1α (HIF-1α), are becoming more apparent, yet at the commencement of this thesis no study had explored whether hypoxia induced signalling can be adopted to regulate the homing and engraftment of transplanted HSCs. The aim of this DPhil project was thus to investigate whether hypoxic conditions as detected in the BM influence the adhesion of UBC-CD133+ cells to osteoblasts, BM stromal cells and BM endothelial cells-60 (BMEC-60), as well as their transmigration towards chemokine SDF-1α across BMEC-60. Increasing the exposure of UCB-CD133+ cells to 1.5% O2 doubled the percentage of transmigrating cells (p<0.05), and while hypoxia stimulated UCB-CD133+ cells preferentially adhered to IL-1β stimulated BMEC-60, their adhesion to non-stimulated (BMEC-60) was significantly improved (p<0.001). To help unravel the underlying molecular mechanisms, we attempted to examine the potential involvement of hypoxia regulated scaffolding protein HEF-1/NEDD9/Cas-L (HEF-1) in the increased percentage of migrating UCB-CD133+ cells after hypoxia pre-conditioning. The role of HEF-1 in HSCs is unexplored, and its multifunctional contribution in a variety of processes including cell migration, attachment and invasion make HEF-1 a prime candidate as a contributing homing molecule. After identifying a suitable short-hairpin RNA (shRNA) sequence to knockdown HEF-1, generating lentiviral (LV)-particles in house and optimising transduction protocols, HEF-1 knockdown was achieved in haemopoietic model cell lines KG-1 and KG-1A (KG-1/KG-1A–HEF1). Significantly decreased KG-1A–HEF1 cell adhesion to non-stimulated BMEC-60 was detected. Together, these studies provide a promising platform to further explore the role of HEF-1 in hypoxia induced UCB-CD133+ cell transmigration towards the key homing molecule SDF-1α.

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46

Van, Gend Tania Anli. "Effect of a South African medicinal plant on antiretroviral drug induced abnormalities in rats." Thesis, Nelson Mandela Metropolitan University, 2008. http://hdl.handle.net/10948/1080.

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The worldwide AIDS epidemic is known to have had a profoundly negative social, economic and personal impact and has taken a heavy toll on existing health care systems, particularly in developing countries. South Africa is experiencing an HIV epidemic with enormous social and economic consequences. Lopinavir/ritonavir antiretroviral treatment has been accredited with having a significantly positive effect and is a key advance in controlling HIV morbidity and mortality. An indigenous South African medicinal plant, Sutherlandia frutescens, known for its anti-diabetic properties and immune-boosting effects, is used for treating HIV positive patients suffering from opportunistic infections. Despite the use of the medicinal plant extract as homeotherapeutic medication, there is little evidence of toxicity testing that identifies its potential for interaction with antiretroviral drugs. However, scientific data relating to the mechanism through which Sutherlandia frutescens acts on the immune system has not been comprehensively documented. The aim of this study was to investigate lopinavir/ritonavir induced metabolic abnormalities in rats and whether the introduction of a plant extract of Sutherlandia frutescens would counteract the side effects of ARV medication. The results indicated that the rodents did not become insulin resistant, however, biochemical analysis indicated that extended ARV drug treatment would have caused insulin resistance. Significant morphological changes were found in the livers, kidneys and pancreases of rats exposed to the lopinavir/ritonavir. Rats exposed to the Sutherlandia frutescens plant extract showed improved histopathology with minimal abnormalities.

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47

Larsson, Isak. "Utläsning av jonkammardata." Thesis, Umeå universitet, Institutionen för tillämpad fysik och elektronik, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-176136.

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Tracercenter på Norrlands Universitetssjukhus producerar radiotracers. För att mäta aktiviteten hos de radioaktiva isotoperna används idag en jonkammare tillsammans med mjukvara byggt på Windows XP. Målet med det här examensarbetet är att bygga ny mjukvara som är kompatibelt med Windows 10. Mjukvaran ska tillhandahålla kalibreringsmöjligheter för isotoperna F-18, C-11 och Cs-137 samt kunna överföra uppmätt värde till datahanteringssystemet PETra.Med användandet av kodspråket Python och biblioteket TkInter har ett användargränsnitt och bakomliggande funktionskod utvecklats. Mjukvaran kommunicerar med både jonkammare och PETra seriellt via COM-Port. Linjäritetstester har gjorts för jonkammaren som påvisat god linjäritet. Detta resultat bekräftar mjukvarans tillförlitlighet med en liten felmarginal. Ytterligare tester behövs för att fastställa magnituden av felmarginalen.
Tracercenter at Norrlands University Hospital is a producer of radiotracers. To measure the activity of the radioactive isotopes an Ion Chamber combined with software built on Windows XP is used. The purpose of this thesis is to develop new software for the ion chamber compatible with Windows 10. The software has to provide a calibration function for the isotopes F-18, C-11 and Cs-137 aswell as be able to transfer measured activity to the laboratory information management system PETra.A graphical user interface together with backend code has been developed with Python and the library TkInter. The software communicates with both the ion chamber and PETra with a serial connection via COM-Port. Linearity tests have been made for the ion chamber which has shown that the output of the ion chamber itself is linear. This result confirms the software’s reliability with a slight margin of error. Further tests is needed to determine the magnitude of the margin of error.

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48

Jalkanen, Ville. "Resonance sensor technology for detection of prostate cancer." Licentiate thesis, Umeå : Tillämpad fysik och elektronik, Umeå univ, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-896.

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49

Rapisarda, Maria Francesca. "Ruolo diagnostico della ricerca di anticorpi verso antigeni del tubulo germinativo di candida albicans in diverse tipologia di pazienti." Doctoral thesis, Università di Catania, 2012. http://hdl.handle.net/10761/1003.

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Tra i pazienti a più alto rischio di sviluppo di IFI vanno certamente considerati i trapiantati di organo solido e di midollo, i pazienti neutropenici con leucemia sottoposti a terapia con chemioterapici, neonati pretermine, pazienti riceventi corticosteroidi e pazienti con sindrome da immunodeficienza acquisita (AIDS). Considerando le problematiche connesse nell effettuare una diagnosi certa di candidosi invasiva, l utilizzo di alcuni esami di laboratorio, tra cui la ricerca di anticorpi verso la fase miceliale di C. albicans, in associazione ad altri parametri di laboratorio e ai dati clinici dei pazienti, potrebbe essere utile per supportare una diagnosi probabile di infezione fungina invasiva sia in pazienti con malattie ematologiche, sia nei trapiantati, sia in quelli ricoverati in terapia intensiva che presentano specifici fattori di rischio per lo sviluppo di infezione. Scopo della tesi è stato valutare il ruolo diagnostico della ricerca di anticorpi verso antigeni del tubulo germinativo di C. albicans in diverse tipologie di pazienti a rischio per lo sviluppo di candidosi invasiva. In particolare, sono stati reclutati 35 pazienti sottoposti a trapianto di rene (TRAP), 53 pazienti critici ricoverati presso l Unità di Terapia Intensiva (UTI) e 36 pazienti oncoematologici (EMAT) che presentavano fattori di rischio compatibili con l eventuale sviluppo di candidosi invasiva. Nel 69,8% (37/53) dei pazienti ricoverati in UTI sono stati osservati titoli anticorpali di 160. Questa percentuale scendeva al 56,6% (30/53) con cut-off di positività maggiore o uguale a 320. Nei pazienti ematologici, la percentuale di positività è stata del 47,2% (17/36) con cut-off di 160 e 25% (9/36) con cut-off di 320. Infine, nei pazienti trapiantati è stato osservato il più basso numero di pazienti positivi con entrambi i cut-off (28,5% e 14,2%). Sulla base di criteri clinici e microbiologici (due consecutive positività all antigene (1-3)-beta-D-glucano più DNA fungino positivo), sono stati individuati 13/53 pazienti UTI e 13/36 pazienti EMAT con candidosi invasiva probabile. Dall analisi dei dati relativa ai pazienti UTI con candidosi invasiva provata e probabile (15) e senza candidosi (38), l uso del cut-off a 320 è risultato significativamente associato allo sviluppo di candidosi invasiva provata e probabile rispetto all utilizzo del cut-off a 160. Nel paziente EMAT, diversamente a quanto osservato nel paziente UTI, è stata evidenziata un associazione statisticamente significativa tra la presenza di anticorpi a titoli di 160 rispetto allo stato di candidosi probabile. Considerando ancora oggi le difficoltà nell effettuare una diagnosi provata di infezione fungina invasiva, diventa sempre più importante selezionare categorie di pazienti con fattori di rischio predisponenti per lo sviluppo di tali infezioni in modo da poter avviare un monitoraggio sierologico stretto che consenta di supportare una precoce diagnosi di infezione fungina invasiva provata e probabile. Sulla base dei dati ottenuti potrebbe essere opportuno utilizzare, per la ricerca di anticorpi verso il tubulo germinativo di C. albicans, cut-off differenti in base al tipo di paziente monitorato in modo da poter ottenere il massimo in termini di sensibilità e specificità.

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50

Rahimi, Bahol. "Implementation of Health Information Systems." Licentiate thesis, Linköping University, Linköping University, MDA - Human Computer Interfaces, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-15677.

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Healthcare organizations now consider increased efficiency, reduced costs, improved patient care and quality of services, and safety when they are planning to implement new information and communication technology (ICT) based applications. However, in spite of enormous investment in health information systems (HIS), no convincing evidence of the overall benefits of HISs yet exists. The publishing of studies that capture the effects of the implementation and use of ICT-based applications in healthcare may contribute to the emergence of an evidence-based health informatics which can be used as a platform for decisions made by policy makers, executives, and clinicians. Health informatics needs further studies identifying the factors affecting successful HIS implementation and capturing the effects of HIS implementation. The purpose of the work presented in this thesis is to increase the available knowledge about the impact of the implementation and use of HISs in healthcare organizations. All the studies included in this thesis used qualitative research methods. A case study design and literature review were performed to collect data.

This thesis’s results highlight an increasing need to share knowledge, find methods to evaluate the impact of investments, and formulate indicators for success. It makes suggestions for developing or extending evaluation methods that can be applied to this area with a multi-actor perspective in order to understand the effects, consequences, and prerequisites that have to be achieved for the successful implementation and use of IT in healthcare. The results also propose that HIS, particularly integrated computer-based patient records (ICPR), be introduced to fulfill a high number of organizational, individualbased, and socio-technical goals at different levels. It is therefore necessary to link the goals that HIS systems are to fulfill in relation to short-term, middle-term, and long-term strategic goals. Another suggestion is that implementers and vendors should direct more attention to what has been published in the area to avoid future failures.

This thesis’s findings outline an updated structure for implementation planning. When implementing HISs in hospital and primary-care environments, this thesis suggests that such strategic actions as management involvement and resource allocation, such tactical action as integrating HIS with healthcare workflow, and such operational actions as user involvement, establishing compatibility between software and hardware, and education and training should be taken into consideration.

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Dissertations / Theses on the topic 'Medical / Laboratory Medicine'

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