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Dissertations / Theses on the topic 'Corona Viruse'
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Luna, Espinoza Luis Ramiro. "Caracterización molecular de Corona virus (CoV) detectados en crías de alpacas (Vicugna pacos)." Master's thesis, Universidad Nacional Mayor de San Marcos, 2012. https://hdl.handle.net/20.500.12672/15831.
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Publicación a texto completo no autorizada por el autor<br>Busca detectar y caracterizar molecularmente a coronavirus a partir de muestras de heces diarreicas y tejido pulmonar con lesiones neumónicas en crías de alpacas de 1-6 semanas de edad procedentes de un centro de crianza ubicado en el departamento de Puno. Se detectó el virus mediante la prueba de RT-PCR anidada, usando cebadores externos específicos a los 3 géneros de Coronavirus (alfa, beta y gammacoronavirus) y cebadores internos específicos sólo para betacoronavirus. Se detectaron secuencias del género betacoronavirus en el 67% (10/15) de muestras diarreicas y en el 50% (8/16) de muestras de tejido pulmonar. Para la realización del análisis molecular de las secuencias virales detectadas, se procedió a amplificar mediante PCR fragmentos del gen codificante de la espícula (S), usando para ello 8 pares de cebadores derivados de secuencias consenso en Coronavirus bovino (BCoV). Se observó amplificación de fragmentos del gen S sólo en 3 muestras procedentes de heces diarreicas, de estas, 2 amplificaron para todos los cebadores y 1 amplificó para un par de cebadores que se alineaban a nivel del dominio S2 del gen S. No se logró obtener ningún fragmento en las muestras restantes (7 de heces y 8 de tejido pulmonar). Las secuencias del fragmento común obtenidos en estas 3 muestras fueron similares, y el análisis filogenético reveló una mayor identidad genética (99.7%) principalmente hacia cepas BCoV diarreicas aisladas en Estados Unidos respecto al aislado norteamericano de CoV de alpaca (98.3%). El presente trabajo constituye la primera evidencia de betacoronavirus presente en casos de neumonía en crías de alpacas y la cercana identidad genética de cepas de CoV de alpacas peruanas con cepas norteamericanas.
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Liu, Lei. "Immunology of herpes simplex keratitis and its treatment by corneal transplantation." Thesis, Available from the University of Aberdeen Library and Historic Collections Digital Resources. Online version available for University member only until Sep. 7, 2010, 2009. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?application=DIGITOOL-3&owner=resourcediscovery&custom_att_2=simple_viewer&pid=33585.
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Fischer, Marie-Madeleine. "Evaluation and application of a competitive ELISA for discrimination of antisera against porcine respiratory corona virus (PRCV) and transmissible gastroenteritis virus (TGEV) /." [S.l.] : [s.n.], 1992. http://www.ub.unibe.ch/content/bibliotheken_sammlungen/sondersammlungen/dissen_bestellformular/index_ger.html.
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Spahi, Majlinda. "Sex differences in COVID-19 infections." Thesis, Karlstads universitet, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kau:diva-78261.
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The Coronavirus disease 2019 (COVID-19) outbreak have shown that there may be sex-dependent differences in morbidity and mortality among individuals contracted with the disease. The aim of the study was to analyse the extent that sex differences appear in COVID-19 infections and to explore whether any differences are due to intrinsic factors in the sexes that cause sex-bias in the disease susceptibility and mortality. The study presents an age and sex-disaggregated analysis of reported cases of total infections, intensive care cases, and deaths across 13 countries due to the disease. The results demonstrated that there is a general trend for the disease prevalence, and it shows a female bias among the proportion of individuals infected with COVID-19. However, males appear to require more intensive care treatment and higher rates of death when compared to females. The results also show that more women than men are reportedly infected by the corona virus up to a certain age. After the age of 60, the proportion of men affected is higher than women, and it is also at this age that the death rate among men increases significantly. In conclusion, the results of this work indicate that males could possibly be at a significantly higher risk of severe disease and death than females, and that the patterns of sex bias in intensive care cases to some extent follows the expected pattern if sex hormones played a role in influencing the immune system response to COVID-19.<br>Utbrottet av Coronavirus sjukdomen 2019 (COVID-19) har visat att det kan finnas könsberoende skillnader i sjuklighet och dödlighet bland individer som drabbats av sjukdomen. Syftet med studien var att analysera i vilken utsträckning könsskillnader förekommer i COVID-19-infektioner och att undersöka om skillnaderna beror på inre faktorer hos könen som möjligtvis orsakar könsfördomar i sjukdomens mottaglighet och dödlighet. Denna studie presenterar en ålder-och könsfördelad analys av totala antalet rapporterade fall, intensivvårdsfall och dödsfall i 13 länder till följd av COVID-19. Resultaten visade att det finns en generell trend för sjukdomens utbredning, och den visar en högre andel kvinnor än män som har smittats med COVID-19. Men det är män som är mer i behov av intensivvård och har högre dödsnivåer i jämförelse med kvinnor. Resultaten visar även att fler kvinnor än män smittas av coronaviruset upp till en viss ålder. Efter 60-årsåldern är andelen drabbade män högre än kvinnor, det är även vid den här åldern som dödsnivån bland män ökar markant. Sammanfattningsvis indikerar resultaten av denna studie att män eventuellt skulle kunna ha en betydligt högre risk för en allvarligare sjukdom och död än kvinnor.
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Herring, Ian Phillip. "Feline Leukemia Virus Detection in Corneal Tissues of Cats by Polymerase Chain Reaction and Immunohistochemistry." Thesis, Virginia Tech, 1998. http://hdl.handle.net/10919/46490.
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Corneal transplantation carries a high rate of success in the domestic cat and is an indicated treatment for specific corneal diseases in this species. The potential for iatrogenic transmission of viral diseases is a well-recognized problem in human corneal transplantation programs and screening donors for certain diseases is routine. Feline leukemia virus (FeLV) is a common agent of disease in domestic cats and available blood tests are highly effective in identification of infected individuals. This study investigates the presence of FeLV within corneal tissues of FeLV infected cats.
Seventeen cats were identified to be positive for serum p27 antigen by enzyme-linked immunosorbent assay (ELISA). Twelve of these individuals were found to be positive on peripheral blood by immunofluorescent antibody (IFA) testing. Seventeen ELISA negative cats were identified to serve as negative controls. Full thickness corneal specimens were collected from all subjects and analyzed for the presence of FeLV proviral DNA and gp70 antigen by polymerase chain reaction (PCR) and immunohistochemical (IHC) testing, respectively.
Eleven (64.7%) positive corneal PCR results were obtained from 17 ELISA positive cats. Of 12 cats which were both ELISA and IFA positive on peripheral blood, 10 (83.3%) had positive corneal PCR results. All corneal tissues from ELISA negative subjects were PCR negative. IHC staining of corneal sections revealed the presence of FeLV gp70 in corneal tissues of nine (52.9%) ELISA positive cats. Of the 12 cats which were both ELISA and IFA positive on peripheral blood, 8 (66.7%) had positive corneal IHC results. Positive IHC staining was localized to the corneal epithelium. Corneal tissues of all ELISA negative cats and all IFA negative cats were negative on IHC testing.
This study reveals FeLV to be present within the corneal epithelium of some FeLV infected cats. Screening potential corneal donors for this virus is warranted.
This work was funded by grants from the American College of Veterinary Ophthalmologists, the Virginia Veterinary Medical Association Pet Memorial Fund, and the DSACS Quick Response Fund.<br>Master of Science
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Nylander, Olof, and Kevin Aspenhed. "Att leda tjänsteföretag under en kris : En kvalitativ studie om hur chefer på tjänsteföretag i Kalmar län bedriver ledarskap under coronaviruspandemin." Thesis, Linnéuniversitetet, Institutionen för organisation och entreprenörskap (OE), 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-105862.
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Research question: How do service company managers believe the coronavirus pandemic has affected their leadership? Purpose: The intention of this study is to investigate managers with a leading role in service companies and how they believe their leadership has changed during the coronavirus pandemic. The purpose of this study is to see how they are consistent with the following theories in leadership during changing conditions and what current managers can learn from the coronavirus pandemic. Theories: Situational leadership II, involved leadership & leadership during crisis. Method: This study conducted a qualitative method, using interviews with managers of four service companies. The interview guide was constructed based on the above mentioned leadership theories. Result: Managers need to communicate clearly during a pandemic. Managers have expressed difficulty in remaining present and motivating employees during crises. Telecommuting has created opportunities for companies to save resources through reduced business travels.
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Joulak, Adam, and Ali Menhem. "STUDENTS PERSPECTIVE ON SHIFTING FROM ON-CAMPUS TO DIGITAL EDUCATION : A qualitative study on the effects of the unexpected change from on-campus to digital education from Malmö university systems development students perspective." Thesis, Malmö universitet, Fakulteten för teknik och samhälle (TS), 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:mau:diva-43398.
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Context: The COVID-19 outbreak has resulted in many changes in education, and it is reasonable to expect that this change would have a significant effect on students. According to government recommendations, many educational institutions around the world have temporarily switched to online learning methods to prevent the spread of the COVID-19 pandemic.Objective: The purpose of this study was to analyze the impact of the sudden shift to online learning, imposed on students due to COVID-19 outbreak.Method: We started a systematic mapping study and analyzed the findings thematically. Furthermore, we conducted interviews with Malmö University students, which were then analyzed using the same approach.Results: We identified 23 publications that were grouped into 9 themes based on student reports of different effects of online education. According to the findings, students often experience technical issues when studying online. Many students believe that communication is crucial for a positive online learning experience. Research also shows that online education benefits students by allowing them to be more flexible and improving their self-study habits. The systematic mapping study on the interview showed that the students did not experience any significant challenges related to technical issues. Many students missed the social aspect of online education and experienced challenges such as lack of communication and difficulties to perform academically.Conclusion: The most significant challenges found were communication and academic performance. Students claim they have lost some or all ways of contact with their peers as a result of the transition to online learning, and the majority believe this has made it more difficult for them to perform academically. The findings cannot be generalized outside of higher institutions in Sweden since different countries have different levels of technological infrastructure which is critical for institutions and for providing students with a smooth and reliable online learning experience.
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Gabrielle, Gillhover. ""Som att uppfinna hjulet medan det rullar" : en kvalitativ intervjustudie om svenska sjukhuskuratorers arbete, mående och hantering under covid-19-pandemin 2020." Thesis, Stockholms universitet, Institutionen för socialt arbete, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-192477.
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The covid-19-pandemic spread across the entire world during 2020 and the hospital counselors’ workplace has during this time been in the centre of pandemic management. The aim of this study has been to investigate how hospital counselors in Sweden experience and manage their health and work during the covid-19-pandemic between January and October 2020. Eight hospital counselors have been studied using semi-structured interviews which were thematically sorted and analyzed based on Antonovsky's theory Sense of Coherence. The results showed that the counselors have experienced a different work situation with new routines such as supporting patients over the phone or while wearing personal protective equipment. The counselors have had to deal with increased patient mortality and more complicated cases that have challenged them emotionally and physically. As a consequence this has involved increased fatigue, muscle tension, worry and anxiety. At the same time, they have felt that they lacked the necessary staffing and work equipment to meet the increased demands. They have handled this by adding more importance to the collegial support and making sure to get a break from information about the pandemic in their spare time.
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Gruvnäs, Amanda. "Avloppsvattenbaserad epidemiologi med fokus på SARS-CoV-2 : Analys inom Västerås kommun." Thesis, Uppsala universitet, Institutionen för biologisk grundutbildning, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-451696.
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Globalt har hela världens befolkning påverkats både ekonomiskt och psykiskt av coronaviruset SARS-CoV-2, som har drabbat så många människor med covid-19 att det klassas som en pandemi. Strax efter pandemins utbrott upptäcktes det att viruset utsöndras från avföring och ut i spillvattennätet som leder till reningsverken. Då virusmängden ökar i avloppsvattnet ökar även covid-19 fallen i samhället. Ökning av virusmängd i avloppsvatten kan nämligen signalera om att det förekommer smittspridning i samhället. Avloppsvattenbaserad övervakning kan dock användas som komplement till andra teststrategier vilket EU-kommissionen har nämnt i en rekommendation. Trender kan analyseras för att i ett tidigt skede informera sjukvård och regioner om ökad smittspridning. På Kungsängens reningsverk i Västerås kommun har Mälarenergi analyserat avloppsvattnet för att ta reda på om ökning av virus i avloppsvatten kan indikera på ökad smittspridning i Västerås kommun. De har samlat in proverna och skickat det till SGS Analytics AB Sweden som har analyserat proverna med RT-qPCR. CT-värdena har normaliserats med vattenflöden. Korrelationstest har gjorts mellan virusmängd i avloppsvattnet och covid-19 fall, dödsfall samt IVA-fall. Det fanns ett signifikant svagt negativt samband mellan virusmängd i avloppsvatten och covid-19 fall per vecka. Mellan virusmängd och IVA-fall eller dödsfall fanns inget samband. Det finns en del felkällor som kan ha påverkat virusmängden. Vid höga vattenflöden kan PCR inhibitorer från tillskottsvatten och lakvatten ha påverkat CT-värdena. Värdena är höga på sommaren trots att covid-19 fall, dödsfall och IVA-fall var som lägst. Inhibitorer skapar direkt eller indirekt högre CT-värden vilket tolkas som lägre virusmängder.
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Ahmad, Doaa. "Grönstrukturens funktion och betydelse för studenternas återhämtning (under covid-19 restriktioner)." Thesis, Malmö universitet, Fakulteten för kultur och samhälle (KS), 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:mau:diva-18791.
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Tidigare forskning har visat att exponering för grön miljö tillhandahåller hälsofördelar. Dessa fördelar indikerar bland annat återhämtningseffekt av stress, trötthet och uppmärksamhetsutmattning, vilket är särskilt viktigt för universitetsstudenter. Därför syftade denna studie att undersöka om det finns en koppling mellan universitetsstudenters kontakt med grönstruktur i/nära studiemiljö och studenternas upplevelse av sin studiemiljö under covid-19 restriktionerna. Detta med hjälp av en dagbokundersökning som förstudie och telefonintervjuer. Analysverktyget bestod av teoretiska ramverk, Attention Restoration Theory (ART) och Stress Reduktion Theory (SRT). Resultat och analys har bekräftat Attention Restoration Theory (ART), där det uppges att gröna naturliga miljöer ger återhämtningseffekt och väcker uppmärksamhet efter en mental trötthet. Därtill bekräftade den även Stress Recovery Theory (SRT), där det uppges att gröna naturliga miljöer ger positiva effekt på stressminskning, -bearbetning och -återhämtning. Slutsatsen till denna undersökning är att grönstruktur har en stor betydelse för universitetsstudenterna, detta då alla väljer att vistas eller komma i kontakt med gröna naturen på ett eller annat sätt, till exempel gå en promenad i naturen eller åka till en stuga i skogen. Att naturen är en del av studenternas vardag verkar vara framför allt en omedveten upplevelse för de flesta och sker utan erkännande eller bearbetning av miljön. Dock framkommer det att processen kan vara medveten för vissa studenter.<br>Previous research has shown that exposure to the green environment provides health benefits. These benefits indicate among other things, recovery effect of stress, fatigue and attention-exhaustion, which is especially important for university students. Therefore, this study aimed to investigate whether there is a connection between university students' contact with the green structure in / near the study-environment and the students' experience of their study environment during the covid-19 restrictions. This with the help of a diary-survey as a pilot-study and telephone interviews. The analysis tool consisted of theoretical frameworks, Attention Restoration Theory (ART) and Stress Reduction Theory (SRT). Results and analysis have confirmed Attention Restoration Theory (ART), where it states that green natural environments have a recovery effect and attracts attention after a mental fatigue. In addition, it also confirmed the Stress Recovery Theory (SRT), which states that green natural environments have a positive effect on stress reduction, processing and recovery. The conclusion of this study is that green structure is of great importance to university students, as everyone chooses to reside or get in touch with green nature in one way or another, for example going for a walk in a green environment or staying in a cottage in the forest. That nature is a part of the students' everyday life seems to be above all an unconscious experience for most and takes place without recognition or processing of the environment. However, it appears that the process may be conscious for some students.
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Zens, Oscar. "Informationsvideo om coronaviruset : Att visualisera textbaserad information så att den blir tillgänglig." Thesis, Mälardalens högskola, Akademin för innovation, design och teknik, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:mdh:diva-49057.
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I takt med coronaviruspandemin arbetade myndigheten för samhällsskydd och beredskap (MSB) med att utveckla information om coronaviruset. En del av den nya informationen publicerades på krisinformation.se. Informationen som fanns på krisinformation.se var överlag textbaserad. I det här arbetet har jag utifrån ett kvalitativt förhållningssätt arbetat med att göra delar av den textbaserade informationen multimodal, men med särskild hänsyn till de med dyslexi. Syftet är att med en informationsvideo visualisera textbaserad information på ett multimodalt sätt. Målet med arbetet var att utforma ett gestaltningsförslag som informerar och engagerar betraktaren till att vilja bromsa takten som smittspridningen sprider sig på. I ett försök att uppnå syftet och målet utformades följande frågeställning: Hur tillgängliggörs information med illustrationer och animationer i en informationsvideo? Frågeställningen besvarades genom att samla empiri utifrån en ikonologisk analys av en befintlig informationsvideo. Vidare utformades ett gestaltningsförslag som testades vid två tillfällen via intervjuer. Vid det första tillfället testades en storyboard och vid det andra tillfället testades en informationsvideo. Vid utformandet av gestaltningsförslaget var kognitions- och retorik-teori av särskild stor betydelse. Det främsta fyndet är att de med dyslexi inte verkar ha några större problem med att ta till sig information som kommuniceras med illustrationer, animationer och ljud i en informationsvideo.<br>In line with the coronavirus pandemic, the Swedish Civil Contingencies Agency (MSB) worked to develop information about the coronavirus. Some of the new information was published on krisinformation.se. The information found on krisinformation.se was generally text-based. In this essay I have worked on making parts of the text-based information multimodal with a qualitative approach, but with a special attention to those with dyslexia. The purpose is to visualize text-based information in a multimodal way with an information video. The goal was to create a design proposal that can inform and engages the viewer to slow down the spread of infection. In order to achieve the purpose, the following question was designed: How is information made available with illustrations and animations in an information video? The question was answered by collecting empirical data based on an iconological analysis of an existing explainer video. Furthermore, I created a design proposal that was tested on two occasions via interviews. On the first occasion, a storyboard was tested and on the second occasion an information video was tested. When designing the design proposal, cognition- and rhetoric-theory was of particular importance. The main finding is that those with dyslexia do not seem to have any major problems in acquiring information that is communicated with illustrations, animations and sounds in an information video.
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Molander, Adelie. "När Storkyrkan ställde om : En studie av Stilla veckan och påsken i Storkyrkan under pandemin 2020." Thesis, Uppsala universitet, Teologiska institutionen, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-412473.
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In times of social distancing and restrictions, ecclesiological challenges arise for the church as a room that under normal circumstances gather people for services. When the church cannot be used the way it is intended to, it raises questions about the functions of the room. The new corona virus pandemic is a crisis that challenges our perception of the church buildings’ functions and aspects. This thesis is a case study that took place in the Cathedral of Stockholm, also called Storkyrkan, during Holy week and Easter. The purpose of this thesis is to study what ecclesiological implications this new reality has on how co-workers and visitors make use of the room. Through observation of the room and interviews of visitors and co-workers I identify five aspects of Storkyrkan that characterize what functions a church building can have during a crisis. The study finds that through the circumstantial changes of the usage of the room, the materiality of it is amplified. It also shows that many types of people visit and use the room in various ways. They are all connected as a collective in a network through the words, artifacts, music, and practises that are a part of this space. Instead of closing due to the pandemic, Storkyrkan was an open room which generated possibilities for people to use it. In times of social distancing, when people are encouraged to stay away from each other, the church brought people together, though in a much smaller number. This happened both in the physical room and in the virtual room online. These are all sources of lived ecclesiology, which is understood through people’s lives and actions.
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SHARMA, VAIBHAV. "APPLICATION OF NANOTECHNOLOGICAL BASED DRUGS IN MANAGEMENT OF COVID-19." Thesis, 2021. http://dspace.dtu.ac.in:8080/jspui/handle/repository/18959.
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The corona virus outbreak is wreaking havoc on healthcare and socioeconomic
growth around the world. Furthermore, the rapid mutation of the corona virus, as
well as adverse effects in a long use, is a significant public health issue. Therefore,
innovative treatment methods are needed. In view of corona virus outbreak, this
article is about the nanotechnology, that holds tremendous promise for
understanding the virus's structure, development, and lifespan. Nanotechnology
has the potential to open up new avenues for the advancement of cost-effective
and scalable detection methods, personal protective equipment that is both secure
and efficient, as well as modern medical solutions. We go through the basic
contributions that nanotechnology can make in the fight against COVID-19 and
other pandemics in greater detail. Since coronaviruses are nanoscale in size,
nanobiotechnology holds the command in treating and controlling the surge of
corona virus. The microbes and nanostructures interaction is rapidly
revolutionising the biomedical sector, with benefits in therapeutic and diagnostic
applications.
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Medina, Raiza Silveira. "A noticiabilidade e a opinião no webjornalismo: A cobertura do G1, O Antagonista e 247 da pandemia do novo corona virus." Master's thesis, 2021. https://hdl.handle.net/10216/135674.
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Medina, Raiza Silveira. "A noticiabilidade e a opinião no webjornalismo: A cobertura do G1, O Antagonista e 247 da pandemia do novo corona virus." Dissertação, 2021. https://hdl.handle.net/10216/135674.
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Tinunin, Daniela Tatiana. "Características urbanas y la actividad de oviposición de Aedes aegypti vector de virus Dengue en la ciudad de Córdoba." Bachelor's thesis, 2022. http://hdl.handle.net/11086/23859.
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83 h. + Anexo. ils.; tabls.; maps.; figuras. Contiene Referencia Bibliográfica.<br>Aedes aegypti es un mosquito domiciliario vector del virus Dengue cuya enfermedad afecta a nivel global entre 100 y 400 millones de personas anualmente. En las últimas décadas este mosquito se ha expandido desde las regiones tropicales y subtropicales hacia regiones templadas, incluyendo la ciudad de Córdoba. El objetivo de este trabajo es estudiar la relación entre la actividad de oviposición de Ae. aegypti y las características urbanas en dicha ciudad. Se seleccionaron 24 sitios de muestreo, distribuidos en tres zonas de diferente nivel de urbanización (escala de 1800 metros) donde se colocaron ovitrampas en el interior y exterior de las viviendas para registrar la actividad de oviposición del mosquito en el periodo comprendido entre noviembre de 2019 y marzo de 2020. Se obtuvieron valores (semanales y promedios del periodo completo) medios, mínimos y máximos de temperatura, humedad relativa y presión atmosférica de tres estaciones meteorológicas. Se cuantificaron las precipitaciones acumuladas y se incluyeron retardos en las variables. Se estimaron las proporciones de coberturas del suelo (vegetación, suelo desnudo y superficie impermeable) en un área circundante de 150 metros de radio en cada sitio de muestreo a partir de la clasificación supervisada de una imagen satelital Sentinel 2 y se calcularon los valores medios, mínimos y máximos del Índice Normalizado de Diferencia de Edificación (NDBI) y el Índice Normalizado de Diferencia de Vegetación (NDVI). Posteriormente se reordenaron los sitios de muestreo en tres niveles de urbanización según los valores medios de NDVI en una escala de 150 metros de radio. Se realizó un análisis descriptivo-exploratorio y se evaluó el efecto de las variables explicativas sobre las variables respuestas “número total de huevos colectados en el exterior de cada sitio” y “número de huevos colectados semanalmente en el exterior” mediante la aplicación de modelos lineales generalizados (GLM) y modelos generalizados mixtos (GLMM) respectivamente. En el último se incluyó a los sitios de muestreo como factor aleatorio. Las variables cualitativas niveles de urbanización a escala de 1800 metros y 150 metros se incluyeron en los GLM. Características urbanas y la actividad de oviposición de Aedes aegypti vector de virus Dengue en la ciudad de Córdoba. También se comparó la actividad de oviposición en el interior y exterior de las viviendas en tres periodos (de baja actividad, alta actividad y periodo completo) a través de pruebas no paramétricas de Wilcoxon. El GLMM obtenido permite explicar un 26 % de la variación en el número de huevos colectados semanalmente en el exterior considerando a la temperatura mínima con retardo de siete semanas y las precipitaciones acumuladas con retardo de cuatro semanas. Dichas variables describen una relación positiva con la variable respuesta. Por otro lado, mediante el GLM obtenido se encontró que la superficie impermeable presenta una asociación negativa con el número total de huevos colectados en el exterior de cada sitio dentro de cada nivel de urbanización en la escala de 150 metros. Dicho modelo explica un 33% de la variabilidad en la variable respuesta. A su vez, no se hallaron diferencias significativas en el número de huevos colectados total y semanalmente entre los tres niveles de urbanización a escala de 1800 y 150 metros. Por otra parte, se encontró mayor número de huevos de Ae aegypti en el exterior que en el interior durante los tres periodos analizados (baja actividad, alta actividad y periodo completo) siendo este estudio el primero en describir la actividad de oviposición en el interior y exterior de las viviendas en la Ciudad de Córdoba. El bajo porcentaje de variabilidad explicada en el número de huevos colectados en los modelos indica que otras variables no contempladas podrían estar influyendo en la actividad de oviposición del vector. En consecuencia, los resultados obtenidos refuerzan la premisa de que son múltiples los factores que afectan la actividad de oviposición de Ae. aegypti entre los que se encontrarían factores ambientales, demográficos y socio-económicos.<br>Fil: Tinunin, Daniela Tatiana. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Instituto de Investigaciones Biológicas y Tecnológicas-CONICET-UNC. Argentina.<br>Fil: Tinunin, Daniela Tatiana. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Centro de Investigaciones Entomológicas de Córdoba. Argentina.
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Seiler, Erina Noé. "Actividad estacional de los virus Saint Louis encephalitis y West Nile en la comunidad de aves silvestres en un parche de Espinal, Córdoba." Bachelor's thesis, 2019. http://hdl.handle.net/11086/11567.
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Tesina (Grado en Ciencias Biológicas)--Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales.
Lugar de Trabajo: Instituto de Virología Dr. José María Vanella. Facultad de Ciencias Médicas. Universidad Nacional de Córdoba. 2019. 48 h. con Anexos. tabls.; grafs.; maps. Contiene Referencia Bibliográfica.<br>Los virus Saint Louis encephalitis (SLEV) y West Nile (WNV) son arbovirus que se mantienen a través de la transmisión biológica vectorial entre artrópodos y vertebrados. La red de transmisión estaría integrada por mosquitos del género Culex como vectores y aves Passeriformes y Columbiformes como hospedadores. Estudios previos demuestran que un amplio número de especies de aves silvestres se encuentran expuestas a estos virus en las provincias de Chaco, Tucumán y Córdoba (Argentina). El objetivo de este trabajo fue evaluar la actividad temporal de los virus SLE y WN en comunidades de aves residentes y migratorias en un foco de transmisión enzoótico, en la localidad de La Para, Provincia de Córdoba. Las aves fueron capturadas, determinadas taxonómicamente y se obtuvo una muestra de sangre para la detección de anticuerpos neutralizantes (Ac NT) para SLEV y WNV. Se analizaron 860 muestras durante dos períodos de actividad (primavera-verano-otoño) correspondientes a los años 2013 y 2014. Con el objetivo de determinar el efecto de la estación, especie aviar y período de actividad viral sobre la presencia /ausencia de anticuerpos en aves para los virus SLE y WN, se construyeron Modelos Lineales Generalizados y se realizó la selección de los mismos en base al criterio de Información de Akaike (AIC). Se utilizaron imágenes satelitales a fin de obtener los valores medios y máximos de NDVI ( Índice de vegetación de diferencia normalizada) con el propósito de analizar el posible efecto de esta variable ambiental sobre la actividad viral. El modelo que mejor explicó la presencia/ausencia de anticuerpos para SLEV fue el de estación, pero ninguna de las variables analizadas logró explicar la presencia/ausencia de Ac NT para WNV. No se observó un efecto de los valores de NDVI sobre la presencia/ausencia de Ac NT ni sobre la seroprevalencia por estación para SLEV. El análisis serológico realizado durante este trabajo permitió detectar la actividad enzoótica y endémica para ambos virus en un parche de espinal, confirmando hallazgos de trabajos anteriores. Sin embargo, se observa una disminución de los valores de seroprevalencia para ambos virus comparando períodos previos. El SLEV presentó un pico de actividad durante el otoño de cada período. En cuanto al WNV, se observaron dos picos de actividad en el segundo período estudiado: en primavera y en otoño. La alta y constante seroprevalencia para el SLEV en Columbina picui, confirma el rol de esta especie como amplificador de este virus en este ecosistema. Las variaciones estacionales observadas podrían ser el resultado de las variaciones poblacionales típicas de los mosquitos vectores. Las diferencias observadas en el grado de exposición de las especies aviares a estos virus podría indicar la utilización de distintos mosquitos vectores por parte de estos. Este trabajo realiza un nuevo aporte al conocimiento sobre la temporalidad de los virus SLE y WNV y las especies aviares potencialmente implicadas en las redes de transmisión del sitio analizado.
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Salem, Insaf. "Étude de la reconstitution de l’immunité spécifique au cytomégalovirus et au virus de la varicelle suite à la transplantation de sang de cordon ombilical." Thèse, 2016. http://hdl.handle.net/1866/15992.
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La transplantation de sang de cordon ombilical (TSCO) constitue un traitement de choix pour une multitude de pathologies hématologiques malignes et non malignes chez l’enfant et dans certains cas l’adulte. La TSCO est associée à certaines complications, dont une reconstitution immunitaire plus lente et une incidence élevée d’infections opportunistes, notamment celles reliées au cytomégalovirus (CMV) et au virus varicella-zoster (VZV). Dans le cadre de ce travail, nous nous sommes intéressés dans un premier temps à la caractérisation de la reconstitution immunitaire spécifique au CMV et au VZV. Nos résultats ont démontré que la reconstitution de l’immunité cellulaire ne requiert ni un statut séropositif pré-transplantation ni le développement de la maladie. De plus, des reconstitutions spontanées ont été détectées chez certains patients séronégatifs vis-à-vis du CMV ou du VZV. Outre le fait qu’elle se manifeste surtout à partir de 6 mois post-transplantation, ladite reconstitution mérite le qualificatif de « protectrice » en termes de réactivations virales et du développement de signes cliniques lorsqu’une fréquence de 150 cellules produisant l’IFN-γ/million est dépassée. Toutefois, moins de 5% des patients développent une réponse T anti-VZV et anti-CMV au cours 100 premiers jours suivant la TSCO. Il est donc possible que les lymphocytes CD8+ T provenant du SCO, comparativement à leurs homologues provenant de la moelle osseuse (MO), présentent un défaut de fonctionnalité, communément appelé « épuisement clonal ». La caractérisation du répertoire de récepteurs inhibiteurs exprimés par les cellules T CD8+ suivant la TSCO ou la transplantation de moelle osseuse (TMO) a révélé une augmentation significative de la fréquence des cellules exprimant PD-1 tôt suivant la transplantation. Cette population, caractérisée majoritairement par un phénotype effecteur-mémoire (EM), démontre une perte significative de la capacité proliférative et exprime moins d'IFN-γ, d'IL-2, de TNF-α et de CD107a. Une meilleure caractérisation de la reconstitution immunitaire après TSCO permettrait, d'une part de sélectionner des biomarqueurs en vue d’une meilleure gestion des patients à risques de développer des infections virales et/ou de rechuter, et d'autre part d'améliorer leur pronostic.<br>Umbilical cord blood transplantation (UCBT) is a treatment of choice for a variety of hematological malignancies and non-malignant diseases in children and, in some cases, in adults. UCBT is associated with a slower immune reconstitution and a high incidence of viral infections, especially related to cytomegalovirus (CMV) and the varicella-zoster virus (VZV). As part of this work, we aimed to assess the reconstitution of CMV and VZV-specific T cell responses. Neither pre-transplant serostatus nor disease development is required for development of T cell mediated immunity. Moreover, spontaneous reconstitution detected in some patients who were seronegative for CMV or VZV. Detected especially after 6 months post-transplant, antiviral responses are protective in terms of viral reactivation and development of clinical signs, when a frequency of 150 cells producing d'IFN-γ / million is achieved. However, less than 5% of patients develop an antiviral response during the first 100 following UCBT. Compared to their bone marrow (BM) counterparts, UCB CD8+ T lymphocytes may be functionally impaired, a state commonly called « clonal exhaustion ». Characterization of the inhibitory receptors repertoire expressed by CD8+ T cells following UCBT and BMT showed a significant increase in the frequency of cells expressing PD-1 early after transplantation. This population, mainly characterized by effector phenotype, showed a significant loss of proliferative capacity and produced less IFN-γ, IL-2, TNF-α and CD107a. An improved understanding of the CD8+ T cell compartment following UCBT, as well as biomarkers related to T cell exhaustion will decrease infection, transplant related mortality and correlate with better prognosis
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Grenier, Anne-Julie. "Étude de l’immunité antivaricelleuse chez l’enfant transplanté au moyen de moelle osseuse ou de sang de cordon ombilical." Thèse, 2010. http://hdl.handle.net/1866/3962.
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L’infection primaire au VZV et la réactivation du VZV latent sont fréquemment observées à la suite d’une GMO ou d’une GSCO, ce qui cause de sérieuses complications chez le patient. Pour prévenir ces infections, une prophylaxie antivirale est administrée systématiquement chez tous les greffés de MO ou de SCO, alors qu’il n’existe aucun consensus sur la durée optimale d’une telle prophylaxie. Pour résoudre ce problème, notre objectif est de développer et valider une méthode ELISpot-VZV-IFN- qui permettra de suivre la reconstitution de l’immunité à médiation cellulaire anti-VZV chez les receveurs de GMO ou de GSCO et ainsi déterminer le moment opportun pour réduire ou interrompe la prophylaxie chez les receveurs de greffes de CSH. Dans un premier temps, des valeurs-seuil de la réponse à médiation cellulaire anti-VZV chez la population pédiatrique saine ont dû être générées. À la lumière de nos résultats, un enfant avec un résultat ELISpot-VZV-IFN- > 190.0 SFU/106 PBMC devrait être protégé contre une possible infection à VZV. Pour valider cette étude, une étude prospective de la reconstitution immunitaire anti-VZV a été effectuée chez 9 enfants greffés de MO ou de SCO. Nos résultats préliminaires ont montré qu’il n’y avait eu aucune reconstitution significative de l’immunité à médiation cellulaire anti-VZV dans les 18 premiers mois post-transplantation chez 8 de ces 9 enfants.
Les résultats de ces expériences vont fournir d’importantes informations quant à la reconstitution de l’immunité anti-VZV à la suite d’une GMO ou d’une GSCO et pourraient permettre l’amélioration des soins apportés aux receveurs de GMO ou de GSCO.<br>Primary infection with VZV and reactivation of latent VZV are commonly observed following BMT and UCBT, leading to serious complications in patients. As a result, antiviral prophylaxis is systematically administered to BMT and UCBT recipients, yet there is no consensus that defines its optimal duration. To resolve this problem, our objective was to develop and validate a VZV-IFN--ELISpot with which reconstitution of VZV immunity can be followed in BMT and UCBT recipients, providing clinicians a practical tool to gauge the need for and adjust antiviral prophylaxis in individual HSCT recipients. First of all, threshold values for anti-VZV immunity in healthy pediatric subjects were generated. Based on our results, a child exhibiting > 190.0 VZV-specific SFU /106 PBMC should be protected against a possible VZV infection. To validate these results, a prospective study on the recovery of VZV-specific T cell immunity was performed on 9 children following BMT or UCBT. Preliminary results demonstrated that there was no significant recovery of VZV-specific T cell immunity in the first 18 months post-transplantation in 8 of 9 cases.
Results of these experiments will yield important new information regarding reconstitution of anti-VZV immunity following BMT and UCBT and could lead to improvements in clinical management of BMT and UCBT recipients.
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Bah, Ramatoulaye. "Les immunoglobulines intraveineuses et la réponse spécifique des cellules T dans la prévention de la maladie lymphoproliférative post-greffe associée au virus Epstein-Barr chez les enfants greffés de cellules souches hématopoïétiques." Thèse, 2015. http://hdl.handle.net/1866/13540.
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