Увійти

Готові списки джерел за темами / Biophysical screening

Добірка наукової літератури з теми "Biophysical screening"

Автор: Grafiati

Опубліковано: 7 вересня 2022

Оформте джерело за APA, MLA, Chicago, Harvard та іншими стилями

Оберіть тип джерела:

Ознайомтеся зі списками актуальних статей, книг, дисертацій, тез та інших наукових джерел на тему "Biophysical screening".

Біля кожної праці в переліку літератури доступна кнопка «Додати до бібліографії». Скористайтеся нею – і ми автоматично оформимо бібліографічне посилання на обрану працю в потрібному вам стилі цитування: APA, MLA, «Гарвард», «Чикаго», «Ванкувер» тощо.

Також ви можете завантажити повний текст наукової публікації у форматі «.pdf» та прочитати онлайн анотацію до роботи, якщо відповідні параметри наявні в метаданих.

Зміст

Статті в журналах
Дисертації
Частини книг
Тези доповідей конференцій

Статті в журналах з теми "Biophysical screening":

1

Genick, Christine Clougherty, Danielle Barlier, Dominique Monna, Reto Brunner, Céline Bé, Clemens Scheufler, and Johannes Ottl. "Applications of Biophysics in High-Throughput Screening Hit Validation." Journal of Biomolecular Screening 19, no. 5 (April 2, 2014): 707–14. http://dx.doi.org/10.1177/1087057114529462.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Анотація:

For approximately a decade, biophysical methods have been used to validate positive hits selected from high-throughput screening (HTS) campaigns with the goal to verify binding interactions using label-free assays. By applying label-free readouts, screen artifacts created by compound interference and fluorescence are discovered, enabling further characterization of the hits for their target specificity and selectivity. The use of several biophysical methods to extract this type of high-content information is required to prevent the promotion of false positives to the next level of hit validation and to select the best candidates for further chemical optimization. The typical technologies applied in this arena include dynamic light scattering, turbidometry, resonance waveguide, surface plasmon resonance, differential scanning fluorimetry, mass spectrometry, and others. Each technology can provide different types of information to enable the characterization of the binding interaction. Thus, these technologies can be incorporated in a hit-validation strategy not only according to the profile of chemical matter that is desired by the medicinal chemists, but also in a manner that is in agreement with the target protein’s amenability to the screening format. Here, we present the results of screening strategies using biophysics with the objective to evaluate the approaches, discuss the advantages and challenges, and summarize the benefits in reference to lead discovery. In summary, the biophysics screens presented here demonstrated various hit rates from a list of ~2000 preselected, IC50-validated hits from HTS (an IC50 is the inhibitor concentration at which 50% inhibition of activity is observed). There are several lessons learned from these biophysical screens, which will be discussed in this article.

2

Linke, Pawel, Kwame Amaning, Melanie Maschberger, Francois Vallee, Valerie Steier, Philipp Baaske, Stefan Duhr, Dennis Breitsprecher, and Alexey Rak. "An Automated Microscale Thermophoresis Screening Approach for Fragment-Based Lead Discovery." Journal of Biomolecular Screening 21, no. 4 (December 2, 2015): 414–21. http://dx.doi.org/10.1177/1087057115618347.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Анотація:

Fragment-based lead discovery has proved to be an effective alternative to high-throughput screenings in identifying chemical matter that can be developed into robust lead compounds. The search for optimal combinations of biophysical techniques that can correctly and efficiently identify and quantify binding can be challenging due to the physicochemical properties of fragments. In order to minimize the time and costs of screening, optimal combinations of biophysical techniques with maximal information content, sensitivity, and robustness are needed. Here we describe an approach utilizing automated microscale thermophoresis (MST) affinity screening to identify fragments active against MEK1 kinase. MST identified multiple hits that were confirmed by X-ray crystallography but not detected by orthogonal methods. Furthermore, MST also provided information about ligand-induced aggregation and protein denaturation. The technique delivered a large number of binders while reducing experimentation time and sample consumption, demonstrating the potential of MST to execute and maximize the efficacy of fragment screening campaigns.

3

Kamel, Hassan S., Ahmed M. Makhlouf, and Alaaeldin A. Youssef. "Simplified Biophysical Profile: An Antepartum Fetal Screening Test." Gynecologic and Obstetric Investigation 47, no. 4 (1999): 223–28. http://dx.doi.org/10.1159/000010110.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

4

Renaud, Jean-Paul, and Marc-André Delsuc. "Biophysical techniques for ligand screening and drug design." Current Opinion in Pharmacology 9, no. 5 (October 2009): 622–28. http://dx.doi.org/10.1016/j.coph.2009.06.008.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

5

Patil, Devashree N., Sushama A. Patil, Srinivas Sistla, and Jyoti P. Jadhav. "Comparative biophysical characterization: A screening tool for acetylcholinesterase inhibitors." PLOS ONE 14, no. 5 (May 31, 2019): e0215291. http://dx.doi.org/10.1371/journal.pone.0215291.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

6

Murphy, Samuel L., Anand Bhagwat, Shyrie Edmonson, Shangzhen Zhou, and Katherine A. High. "High-throughput Screening and Biophysical Interrogation of Hepatotropic AAV." Molecular Therapy 16, no. 12 (December 2008): 1960–67. http://dx.doi.org/10.1038/mt.2008.210.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

7

Huang, Renjie, Daniel M. Ayine-Tora, M. Nasri Muhammad Rosdi, Yu Li, Jóhannes Reynisson, and Ivanhoe K. H. Leung. "Virtual screening and biophysical studies lead to HSP90 inhibitors." Bioorganic & Medicinal Chemistry Letters 27, no. 2 (January 2017): 277–81. http://dx.doi.org/10.1016/j.bmcl.2016.11.059.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

8

Ghodsvali, Alireza, Vahid Farzaneh, Hamid Bakhshabadi, Zahra Zare, Zahra Karami, Mohsen Mokhtarian, and Isabel S. Carvalho. "Screening of the aerodynamic and biophysical properties of barley malt." International Agrophysics 30, no. 4 (October 1, 2016): 457–64. http://dx.doi.org/10.1515/intag-2016-0017.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Анотація:

AbstractAn understanding of the aerodynamic and biophysical properties of barley malt is necessary for the appropriate design of equipment for the handling, shipping, dehydration, grading, sorting and warehousing of this strategic crop. Malting is a complex biotechnological process that includes steeping; germination and finally, the dehydration of cereal grains under controlled temperature and humidity conditions. In this investigation, the biophysical properties of barley malt were predicted using two models of artificial neural networks as well as response surface methodology. Stepping time and germination time were selected as the independent variables and 1 000 kernel weight, kernel density and terminal velocity were selected as the dependent variables (responses). The obtained outcomes showed that the artificial neural network model, with a logarithmic sigmoid activation function, presents more precise results than the response surface model in the prediction of the aerodynamic and biophysical properties of produced barley malt. This model presented the best result with 8 nodes in the hidden layer and significant correlation coefficient values of 0.783, 0.767 and 0.991 were obtained for responses one thousand kernel weight, kernel density, and terminal velocity, respectively. The outcomes indicated that this novel technique could be successfully applied in quantitative and qualitative monitoring within the malting process.

9

AFZAL, AYSHA, and KHALIDA NASREEN. "BIOPHYSICAL SCORE." Professional Medical Journal 13, no. 03 (June 25, 2006): 362–69. http://dx.doi.org/10.29309/tpmj/2006.13.03.4983.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Анотація:

A pregnancy is defined as high risk when there is a likelihood of anadverse outcome to the woman and or her baby that is greater than the incidence of that outcome in the generalpregnant population. Objectives: To determine the efficacy and predictive value of biophysical profile in detectingperinatal outcome. Design: Observational study. Setting: Obstetrics and Gynaecology department, PNS SHIFA KarachiPeriod: From February 2003 to October 2003. Patients and Methods: The study was carried on 100 randomlyselected high risk pregnant patients who reported to gynae OPD or were referred from different armed forces hospitalsfrom all over sindh . Manning’s biophysical profile excluding nonstress test and including only ultrasound basedparameters were employed for fetal screening ( BPS 8/8). These parameters include four variables i.e fetal breathingmovement, fetal tone, fetal movements, and amniotic fluid volume. Nonstress test and Doppler studies were used asbackup tests where biophysical profile was abnormal. All cases selected were admitted in the hospital and each hadan admission biophysical profile followed by subsequent monitoring. Parameters for abnormal perinatal outcome includefetal distress in labour, five minute apgar score less than 7/10, admission of newborn to intensive care unit and stillbirthor neonatal death. The result of last biophysical profile is compared with perinatal outcome. For statistical analysis thepredictive value, specificity and sensitivity are used to determine the ability of biophysical profile to predict an abnormalperinatal outcome. Results: Out of 100 cases 92 had a normal biophysical profile in the last scan of 8/8. 90 cases hada normal perinatal outcome with A/S > 7/10. In two cases A/S at 1 and 5 minute is < 7/10 with one baby shifted tonursery for delayed cry. 08 cases had an abnormal biophysical profile with scores of 4/8 and 2/8. There was one falsepositive who showed abnormal biophysical profile but baby was born with an A/S of 8/10 at 05 minutes. There was noneonatal death in this study group. The sensitivity of biophysical profile was 77.7%, specificity 98.90%. predictive valuefor a positive test was 87.5%, predictive value for a negative test was 97.8%. Conclusion: Biophysical profile is highlyaccurate and reliable test of diagnosing fetal status.

10

Santoso, Aline T., Xiaoyan Deng, Jeong-Hyun Lee, Kerryn Matthews, Simon P. Duffy, Emel Islamzada, Sarah M. McFaul, Marie-Eve Myrand-Lapierre, and Hongshen Ma. "Microfluidic cell-phoresis enabling high-throughput analysis of red blood cell deformability and biophysical screening of antimalarial drugs." Lab on a Chip 15, no. 23 (2015): 4451–60. http://dx.doi.org/10.1039/c5lc00945f.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Більше джерел

Дисертації з теми "Biophysical screening":

1

Wang, Shao-Fang. "Biochemical and biophysical studies of MDM2-ligand interactions." Thesis, University of Edinburgh, 2012. http://hdl.handle.net/1842/9527.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Анотація:

MDM2, murine double minute 2, is a RING type-E3 ligase protein and also an oncogene. MDM2 plays a critical role in determining the steady levels and activity of p53 in cells using two mechanisms. The N-terminal domain of MDM2 binds to the transactivation domain of p53 and inhibits its transcriptional activity. The RING domain of MDM2 plays a role in the ubiquitination (and degradation) of p53. Several proteins are responsible for the ubiquitination mechanism including the ubiquitin-activating enzyme (E1), ubiquitin-conjugating enzyme (E2) and ubiquitin ligase (E3). Since the E2-E3 interaction is essential for ubiquitination, the protein-protein recognition site is a potential drug target. Two different MDM2 RING constructs were expressed and purified: MDM2RING (residues 386-491) and MDM2RING△C (residues 386-478). Both constructs were characterised using dynamic light scattering, size exclusion chromatography, mass spectrometry, NMR and electron microscopy. E3 ligase activity in vitro was also studied. Taken together these results showed that the MDM2RING construct formed a concentration-dependent oligomeric structure. In contrast, the MDM2RING△C construct formed a dimer at all concentrations. Both MDM2RING and MDM2RING △ C retain E3 ligase activity. However, the MDM2RING△C construct is less active. Full length E2 enzyme UbcH5a was also purified. Various biophysical techniques were used to study its interaction with MDM2 as well as with potential small molecule inhibitors as in principle, small molecules which disrupt the interaction between MDM2 and UbcH5a, could prevent/promote ubiquitination of p53. The dimerisation of MDM2 is important for its E3 activity and the C8-binding site potentially provides a second druggable site. In this work, peptide 9, which has the same sequence as the C-terminus of MDMX (an MDM2 homologue) was found to inhibit MDM2 E3 activity. Various biological techniques including NMR, fluorescence anisotropy, and electrospray mass spectrometry were used to investigate the interaction between two inhibitory peptides and MDM2. A major part of project involved virtual screening (VS) to search for small molecules which can affect MDM2-dependent ubiquitination. Three potential targets were considered: (1) the C8-binding site of MDM2; (2) the UbcH5a-binding site of MDM2; and (3) the MDM2-binding site of UbcH5a. Several small molecules were identified using our virtual screening database-mining and docking programs that were shown to affect MDM2-dependent ubiquitination of p53. In terms of understanding the complex biochemical mechanism of MDM2 this work provides two interesting and functionally relevant observations: (i) the MDM2 RING△C construct is a dimer as this would not be expected form the existing studies, and has less E3 ligase activity than MDM2RING; (ii) small molecules that bind MDM2 on the E2 binding site enhanced E3 ligase activity. One model to explain these observations is that binding of small molecule activators family to the RING induces a change in the conformation of the Cterminal tail residues which may enhance E2 binding.

2

Brown, Christopher John. "Structure-based design of anti-cancer drugs : the use of biophysical techniques for screening and characterization of novel inhibitors of the initiation factor eIF4E." Thesis, University of Edinburgh, 2006. http://hdl.handle.net/1842/15435.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Анотація:

In this work high resolution crystals were produced of full length human eIF4E complexed to m7GTP and the 4E-BP1 motif peptide. The interactions of eIF4E with the cap structure were also analysed by mass spectrometry, revealing a requirement of eIF4E for a guanine monophosphates derivative with a positive delocalised charge on the m7G string. Potential inhibitors for screening were either isolated using virtual screening techniques or synthesised to produce a series of cap mimicking molecules containing a positive delocalised charge. Mass spectrometry identified a series of N7 substituted CMP derivatives that bound to eIF4E in the gas-phase. These compounds were then used in co-crystallisation trials with full length human eIF4E complexed with a 4E-BP1 motif peptide. The co-crystal structures of eIF4E with N7 benzyl derivatives revealed a flipping of the tryptophan 102 to accommodate the bulky N7 group and the expulsion of two structured waters. It also showed that if a para-fluoro group is located on the benzyl modification, then interactions also occur with structured water and an arginine, which explains its increased binding to eIF4E. The flipping of the tryptophan reveals the inherent flexibility in the cap-binding site. The structural information, revealing that the cap-binding site of eIF4E undergoes a conformational change in binding N7 derivatives of GMP with large bulky groups, provides us with valuable insight that can be used in future drug design efforts. The mass spectrometry assay coupled with a clear structure activity relationship, developed on the basis of various “cap-like” ligands studied in the work, gives an excellent starting point for the development of cap-analogue mimics for anti-cancer therapeutics.

3

Menchon, Grégory. "Criblage virtuel et fonctionnel sur le complexe XRCC4/ADN ligase IV/Cer-XLF de ligature des cassures double-brin de l'ADN : application en radiosensibilisation tumorale." Thesis, Toulouse 3, 2015. http://www.theses.fr/2015TOU30395.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Анотація:

En cancérologie, la radiothérapie est une des armes essentielles pour éradiquer les cellules tumorales. Les cassures des deux brins de l'ADN dites "double-brin" qu'elle induit sont particulièrement toxiques et constituent la principale cause de mort cellulaire. La NHEJ (Jonction d'Extrémités Non-Homologues) est la voie métabolique majeure de réparation de ces cassures double-brin de l'ADN et par ce mécanisme, les cellules humaines adoptent une résistance à la radiothérapie. Ce mécanisme de réparation constitue donc une cible de choix pour un traitement anticancéreux combiné en vue d'augmenter la sensibilité des cellules cancéreuses aux rayons ionisants (radiosensibilisation). Au cours du mécanisme NHEJ, la ligature finale des extrémités d'ADN est assurée par le complexe protéique tripartite: XRCC4/ADN Ligase IV/Cernunnos-XLF. Les interfaces protéiques concernées représentent toutes des cibles potentielles dans une stratégie rationnelle d'isolement de molécules inhibitrices, guidée par les structures tridimensionnelles de chaque protéine. A travers des expériences de criblage virtuel et de validation à la fois biophysique et biochimique, nous avons isolé les premières molécules capable de prévenir in vitro les interactions protéine-protéine pour les complexes XRCC4/Lig4 et XRCC4/Cer-XLF, respectivement. Ces composés sont des points de départ pour l'élaboration d'inhibiteurs potentiels de plus haute affinité grâce à l'apport de la biologie structurale, en vue d'un effet radiosensibilisant cellulaire
Radiotherapy is a major weapon used against cancer. Radio-induced DNA double strand breaks (DSB) are the main lesions responsible for cell death. Non-homologous end-joining (NHEJ) is a predominant DSB repair mechanism which contributes to cancer cells resistance to radiotherapy. NHEJ is thus a good target for strategies which aim at increasing the radio-sensitivity of tumors. Through in silico screening and biophysical and biochemical assays, our objective was to find specific ligands for the XRCC4/Lig4 and XRCC4/Cer-XLF protein-protein interactions involved in NHEJ. Here, we isolated the first compounds able to prevent their interaction in vitro. These early stage inhibitors are promising tools for cancer therapy with the hope to develop more specific compounds for cellular assays through the 3D structure of the protein/inhibitor complexes

4

Wilde, Lisa M. "Scanning probe and micropatterning approaches for biomolecular screening applications." Thesis, University of Nottingham, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.272739.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

5

Thalhammer, Armin. "Functional and inhibition studies on 2-oxoglutarate-dependent oxygenases." Thesis, University of Oxford, 2012. http://ora.ox.ac.uk/objects/uuid:41c3f967-0dd2-47dd-8dd4-bc543b626221.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Анотація:

This thesis explores roles of 2-oxoglutarate-dependent (2OG) oxygenases as interfaces that modulate steps in the flow of genetic information in cells in response to oxygen availability. Chapter 1 introduces mechanistic, biochemical and physiological aspects of major subfamilies of 2OG oxygenases, and their established regulatory roles in cells. In addition, structural and functional aspects of the ribosome and the translation process are discussed, with a focus on post-translational ribosome modifications. Chapter 2 investigates histone demethylases, which mediate chromatin-dependent regulation of gene expression and provides proof-of-concept for the rational, structure-guided design of small-molecules for selective inhibition of 2OG oxygenases with roles in cancer and inflammatory disease. Chapter 3 suggests regulatory roles for ten-eleven-translocation (TET)- catalysed DNA hydroxylation; calorimetric and thermal analyses reveal a duplex-stabilizing effect of the epigenetic 5-methylcytosine mark that is reversed upon conversion to 5- hydroxymethylcytosine (also termed the ‘sixth’ DNA base), raising the possibility that 2OG oxygenase catalysis might affect transcription via biophysical effects. Chapter 4 investigates fluoride release assays as a technology to enable medicinal chemistry studies on 2OG oxygenases with roles in fat mass regulation and obesity, cancer and inflammation; studies on the ALKBH5 enzyme show that it is a hypoxically upregulated 2OG oxygenase with a substrate preference distinct from previously characterized ALKBH enzymes. Chapter 5 identifies OGFOD1 as a 2OG-dependent ribosomal protein hydroxylase. OGFOD1 catalysis is conserved from yeast to humans. OGFOD1 catalyses formation of trans-3- hydroxy-L-proline in a highly conserved loop of ribosomal protein S23 proximal to the ribosomal decoding centre, possibly to modulate the interactions of eukaryotic ribosomes with tRNA, mRNA and translation factors in an oxygen-dependent manner. OGFOD1 is the functionally most well-conserved protein-modifying 2OG oxygenase; likewise, ribosomal protein S23 hydroxylation is the most well-conserved post-translational ribosome modification in eukaryotes. Some cell lines require OGFOD1 for proliferation, and scaffolds for OGFOD1- selective inhibitors are developed for use as potential antiproliferative agents and probes for cellular function. Chapter 6 shows the development of assays to investigate whether OGFOD1 catalysis affects ribosome assembly and function, including processivity, accuracy of initiation, elongation and termination, in yeast and mammalian cell lines. Chapter 7 concludes that ribosome hydroxylation might present an additional layer of regulatory complexity by which 2OG oxygenases could enable cells to respond to fluctuating oxygen levels.

6

Parra, Katherine Cristina. "Combination of the Computational Methods: Molecular dynamics, Homology Modeling and Docking to Design Novel Inhibitors and study Structural Changes in Target Proteins for Current Diseases." Scholar Commons, 2014. https://scholarcommons.usf.edu/etd/5093.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Анотація:

In this thesis, molecular dynamics simulations, molecular docking, and homology modeling methods have been used in combination to design possible inhibitors as well as to study the structural changes and function of target proteins related to diseases that today are in the spotlight of drug discovery. The inwardly rectifying potassium (Kir) channels constitute the first target in this study; they are involved in cardiac problems. On the other hand, tensin, a promising target in cancer research, is the second target studied here. The first chapter includes a brief update on computational methods and the current proposal of the combination of MD simulations and docking techniques, a procedure that is applied for the engineering of a new blocker for Kir2.1 ion channels and for the design of possible inhibitors for Tensin. Chapter two focuses in Kir ion channels that belong to the family of potassium-selective ion channels which have a wide range of physiological activity. The resolved crystal structure of a eukaryotic Kir channel was used as a secondary structure template to build the Kir-channels whose crystallographic structures are unavailable. Tertiapin (TPN), a 21 a.a. peptide toxin found in honey bee venom that blocks a type of Kir channels with high affinity was also used to design new Kir channel blockers. The computational methods homology modeling and protein-protein docking were employed to yield Kir channel-TPN complexes that showed good binding affinity scores for TPN-sensitive Kir channels, and less favorable for Kir channels insensitive to TPN block. The binding pocket of the insensitive Kir-channels was studied to engineer novel TPN-based peptides that show favorable binding scores via thermodynamic mutant-cycle analysis. Chapter three is focused on the building of homology models for Tensin 1, 2 and 3 domains C2 and PTP using the PTEN X-ray crystallographic structure as a secondary structure template. Molecular docking was employed for the screening of druggable small molecules and molecular dynamics simulations were also used to study the tensin structure and function in order to give some new insights of structural data for experimental binding and enzymatic assays. Chapter four describes the conformational changes of FixL, a protein of bradyrhizobia japonicum. FixL is a dimer known as oxygen sensor that is involved in the nitrogen fixation process of root plants regulating the expression of genes. Ligand behavior has been investigated after the dissociation event, also the structural changes that are involved in the relaxation to the deoxy state. Molecular dynamics simulations of the CO-bound and CO-unbound bjFixL heme domain were performed during 10 ns in crystal and solution environments then analyzed using Principal Component Analysis (PCA). Our results show that the diffusion of the ligand is influenced by internal motions of the bound structure of the protein before CO dissociation, implying an important role for Arg220. In turn, the location of the ligand after dissociation affects the conformational changes within the protein. The study suggests the presence of a cavity close to the methine bridge C of the heme group in agreement with spectroscopic probes and that Arg220 acts as a gate of the heme cavity.

7

Thorman, Alexander W. "Rational Design of Novel BCL2A1 Inhibitors for Treatment of Autoimmune Diseases: An Integration of Virtual Screening, Transcriptomics and Protein Biophysics." University of Cincinnati / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1543580409766192.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

8

Eichelbaum, Steven Ross. "Screening of Plants for Antibacterial Properties: Growth Inhibition of Staphylococcus aureus by Artemisia Tridentata." FIU Digital Commons, 2016. https://digitalcommons.fiu.edu/etd/3526.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Анотація:

Drug-resistant pathogenic and opportunistic bacteria are increasing in occurrence and prevalence, and pose a dangerous threat to human health. In the search for novel antibiotics with which to combat this threat, plants, specifically those used in traditional medicine with ascribed antibacterial properties, offer a promising and potentially vast source of such therapeutic compounds. The purpose of this study was therefore to screen chemical extracts created from various plant species for antibacterial properties versus pathogenic bacterial species. In the course of these antibacterial assays, we successfully identified a methanol extract derived from Artemisia tridentata tridentata plant material as capable of inhibiting the growth of the opportunistic pathogen Staphylococcus aureus. Three sub-fractions were created using hexane, ethyl acetate and water solvents. Each of these extracts displayed significant antibacterial activity versus a wild-type strain over a period of six hours, at concentrations as low as 62.5 µg/ml. The extracts also demonstrated an enhancement of antibiotic effects when combined with ampicillin, G418 sulfate or amikacin, for a period of up to twelve hours. Though the efficacy of the extracts was lessened when tested against an ampicillin-resistant strain, significant enhancement of the efficacy of this antibiotic was still observed. Gas chromatography-mass spectrometry analysis of these three extracts revealed the sesquiterpene lactone achillin as present in each. Column chromatography of the hexane extract resulted in a fraction retaining its antibacterial activity, and still containing this compound, further implicating it as responsible for the antibacterial activity of this plant. The results of serial dilution and plating of extract-treated samples, along with those of ethidium bromide assays and transmission electron microscopy analysis, indicated a bacteriostatic mechanism of action involving disruption of the bacterial membrane, which is in agreement with the literature on the antibacterial properties of this plant, and those of sesquiterpene lactones, respectively. We therefore conclude that achillin, likely produced as a secondary metabolite by Artemisia tridentata tridentata, possesses growth inhibitory properties versus Staphylococcus aureus, and should be isolated and studied further for the purposes of evaluating its potential use, either as a stand-alone antibiotic, or as an adjunctive therapeutic, in the treatment of drug-resistant bacterial pathogens.

9

Pabrai, Natasha Uday. "The Use of Anti-CD3 Treatment and Genetic Screening to Delay Further Beta Cell Destruction in Type 1 Diabetes." Scholarship @ Claremont, 2013. http://scholarship.claremont.edu/scripps_theses/284.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Анотація:

Individuals under 20 years old have the highest risk of developing type 1 diabetes because their beta cells are destroyed at a faster rate than any other age group. Previous studies have looked at delaying and slowing down the rate of beta cell destruction through the use of anti-CD3 antibody treatments. Specifically, Teplizumab and Otelixizumab drug therapies have been used to treat individuals within 12 weeks of diagnosis. Previous studies done with Teplizumab and Otelixizumab have focused on individuals between 12 and 40 years old; however, there is little research done the effects of these treatments on individuals under 12 years old. Since type 1 diabetes is primarily diagnosed in children the purpose of this proposal is to further the knowledge of the preservation of beta cells in children with the use of Teplizumab and Otelixizumab drugs over 2 years. This study will also focus on the delay of onset type 1 diabetes with the use of Teplizumab in high-risk individuals under 20 years of age. The high-risk individuals will be determined by using genetic screening on individuals with an affected immediate family member. Individuals will also be tested to see if they carry insulin autoantibodies (IAA), protein tyrosine phosphate-related IA-2 molecule (IA-2A), islet cell antibodies (ICA), and glutamic acid decarboxylase (GADA). Individuals that test positive for carrying the DR3/DR4 alleles in the genetic screening and that have two or more autoantibodies present in their immune systems will be selected to participate. The purpose of this proposal is to further understand the impact of anti-CD3 antibody treatment on young individuals diagnosed with type 1 diabetes and to further understand if treatment in young individuals with anti-CD3 antibodies can delay or prevent the onset of type 1 diabetes.

10

Wang, Ling. "Microchannel enhanced neuron-computer interface: design, fabrication, biophysics of signal generation, signal strength optimization, and its applications to ion-channel screening and basic neuroscience research." Doctoral thesis, Universitat Politècnica de Catalunya, 2011. http://hdl.handle.net/10803/52810.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Анотація:

En el presente trabajo, utilizamos técnicas de microfabricación, simulaciones numéricas, experimentos de electrofisiología para explorar la viabilidad en me- jorar la interface ordenador-neurona a través de microcanales, y la biofísica para la generación de señales en los dispositivos con microcanales. También demos- tramos que los microcanales pueden ser usados como una técnica prometedora con alto rendimiento en el muestreo automático de canales iónicos a nivel subce- lular. Finalmente, se ha diseñado, fabricado y probado el micropozo-microcanal como modificación adicional a los arreglos de multielectrodos, permitiendo una alta ganancia en la relación señal/ ruido (en inglés Signal to Noise Ratio SNR), y el registro de múltiples-lugares en poblaciones de baja densidad de redes neu- ronales del hipocampo in vitro. Primero, demostramos que son de alto rendimiento los microcanales de bajo costo con interface neurona-electrodo, para el registro extracelular de la activi- dad neuronal con baja complexidad, por periodos estables de larga duración y con alta ganancia SNR. En seguida, se realiza un estudio mediante experimentos y simulaciones nu- méricas de la biofísica para la generación de las señales obtenidas de los dispositi- vos con microcanales. Basados en los resultados, racionalizamos y demostramos como es que la longitud del canal (siendo 200 μm) y la sección transversal del microcanal (siendo 12 μm2) canaliza a los potenciales de acción para estar dentro del rango de milivolts. A pesar del bajo grado de complexidad envuelto en la fabricación y aplicación, los dispositivos con microcanales otorgan una sola media de valor SNR de 101 76, lo cual es favorablemente comparable con la SNR que se obtiene de desarrollos recientes que emplean electrodos curados con CNT y Si-NWFETs. Más aún, nosotros demostramos que el microcanal es una técnica promete- dora para el alto rendimiento del muestro automático de canales iónicos a nivel subcelular: (1) Información experimental y simulaciones numéricas sugieren que las señales registradas sólo afectan los parches membranales localizados dentro del microcanal o alrededor de 100 μm de las entradas del microcanal. (2) La transferencia de masa de los componentes químicos en los microcanales fue ana- lizada por experimentos y simulaciones FEM. Los resultados muestran que los microcanales que contienen glía y tejido neuronal pueden funcionar como barre- ra de fluido/química. Los componentes químicos pueden ser solamente aplicados a diferentes compartimentos a nivel subcelular. Finalmente, basado en simulaciones numéricas y resultados experimentales, se propone que del micropozo-microcanal, obtenido de la modificación de MEA (MWMC-MEA), la longitud óptima del canal debe ser 0,3 mm y la posición 1 óptima del electrodo intracanal, hacia la entrada más cercana del microcanal, debe ser 0,1 mm. Nosotros fabricamos un prototipo de MWMC-MEA, cuyo hoyo pasante sobre las películas de Polydimethylsiloxane (PDMS) fue microtrabajado a través de la técnica de grabados reactivos de plasma de iones. La baja densidad del cultivo (57 neuronas /mm2) en el MWMC-MEAs permitió que las neuronas vivieran al menos 14 días, con lo que la señal neuronal con la máxima SNR obtenida fue de 142. 2
In this present work, we used microfabrication techniques, numerical simulations, electrophysiological experiments to explore the feasibility of enhancing neuron-computer interfaces with microchannels and the biophysics of the signal generation in microchannel devices. We also demonstrate the microchannel can be used as a promising technique for high-throughput automatic ion-channel screening at subcellular level. Finally, a microwell-microchannel enhanced multielectrode array allowing high signal-to-noise ratio (SNR), multi-site recording from the low-density hippocampal neural network in vitro was designed, fabricated and tested. First, we demonstrate using microchannels as a low-cost neuron-electrode interface to support low-complexity, long-term-stable, high SNR extracellular recording of neural activity, with high-throughput potential. Next, the biophysics of the signal generation of microchannel devices was studied by experiments and numerical simulations. Based on the results, we demonstrate and rationalize how channels with a length of 200 μm and channel cross section of 12 μm2 yielded spike sizes in the millivolt range. Despite the low degree of complexity involved in their fabrication and use, microchannel devices provided a single-unit mean SNR of 101 76, which compares favourably with the SNR obtained from recent developments employing CNT-coated electrodes and Si-NWFETs. Moreover, we further demonstrate that the microchannel is a promising technique for high-throughput automatic ion-channel screening at subcellular level: (1) Experimental data and numerical simulations suggest that the recorded signals are only affected by the membrane patches located inside the microchannel or within 100 μm to the microchannel entrances. (2) The mass transfer of chemical compounds in microchannels was analyzed by experiments and FEM simulations. The results show that the microchannel threaded by glial and neural tissue can function as fluid/chemical barrier. Thus chemical compounds can be applied to different subcellular compartments exclusively. Finally, a microwell-microchannel enhanced MEA (MWMC-MEA), with the optimal channel length of 0.3 mm and the optimal intrachannel electrode position of 0.1 mm to the nearest channel entrance, was proposed based on numerical simulation and experiment results. We fabricated a prototype of the MWMCMEA, whose through-hole feature of Polydimethylsiloxane film (PDMS) was micromachined by reactive-ion etching. The low-density culture (57 neurons/mm2) were survived on the MWMC-MEAs for at least 14 days, from which the neuronal signal with the maximum SNR of 142 was obtained.

Більше джерел

Частини книг з теми "Biophysical screening":

1

Williams, Glyn. "The Pyramid™ Approach to Fragment-Based Biophysical Screening." In Label-Free Technologies for Drug Discovery, 241–53. Chichester, UK: John Wiley & Sons, Ltd, 2011. http://dx.doi.org/10.1002/9780470979129.ch16.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

2

Ciulli, Alessio. "Biophysical Screening for the Discovery of Small-Molecule Ligands." In Protein-Ligand Interactions, 357–88. Totowa, NJ: Humana Press, 2013. http://dx.doi.org/10.1007/978-1-62703-398-5_13.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

3

Park, Hyun-Ju, and So-Jung Park. "Virtual Screening for RNA-Interacting Small Molecules." In Biophysical approaches to translational control of gene expression, 235–52. New York, NY: Springer New York, 2012. http://dx.doi.org/10.1007/978-1-4614-3991-2_12.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

4

Bhunia, Shome S., Mridula Saxena, and Anil K. Saxena. "Ligand- and Structure-Based Virtual Screening in Drug Discovery." In Biophysical and Computational Tools in Drug Discovery, 281–339. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/7355_2021_130.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

5

Scott, Duncan E., Christina Spry, and Chris Abell. "Differential Scanning Fluorimetry as Part of a Biophysical Screening Cascade." In Fragment-based Drug Discovery Lessons and Outlook, 139–72. Weinheim, Germany: Wiley-VCH Verlag GmbH & Co. KGaA, 2016. http://dx.doi.org/10.1002/9783527683604.ch07.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

6

Fasolato, Claudia. "SERS-Active Nanovectors for Single-Cell Cancer Screening and Theranostics." In Surface Enhanced Raman Spectroscopy for Biophysical Applications, 113–35. Cham: Springer International Publishing, 2018. http://dx.doi.org/10.1007/978-3-030-03556-3_5.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

7

Hennig, Michael, Armin Ruf, and Walter Huber. "Combining Biophysical Screening and X-Ray Crystallography for Fragment-Based Drug Discovery." In Topics in Current Chemistry, 115–43. Berlin, Heidelberg: Springer Berlin Heidelberg, 2011. http://dx.doi.org/10.1007/128_2011_225.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

8

Pant, Pradeep, and B. Jayaram. "A Rapid Computational Screening of Millions of Molecules to Identify Sequence-Specific DNA Minor Groove Binders via Physicochemical Descriptors." In Biophysical and Computational Tools in Drug Discovery, 341–67. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/7355_2021_122.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

9

Narayan, Kartik, and Steven S. Carroll. "SPR Screening." In Applied Biophysics for Drug Discovery, 93–105. Chichester, UK: John Wiley & Sons, Ltd, 2017. http://dx.doi.org/10.1002/9781119099512.ch6.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

10

Solovchenko, Alexei. "Screening Pigments: General Questions." In Springer Series in Biophysics, 9–31. Berlin, Heidelberg: Springer Berlin Heidelberg, 2010. http://dx.doi.org/10.1007/978-3-642-13887-4_2.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Тези доповідей конференцій з теми "Biophysical screening":

1

Roshan, Saboora M., and Edward J. Park. "Impairment Screening Utilizing Biophysical Measurements and Machine Learning Algorithms." In 2021 43rd Annual International Conference of the IEEE Engineering in Medicine & Biology Society (EMBC). IEEE, 2021. http://dx.doi.org/10.1109/embc46164.2021.9630022.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

2

Amato, Jussara, Simona Marzano, Bruno Pagano, Nunzia Iaccarino, Anna Di Porzio, Stefano De Tito, Eleonora Vertecchi, Erica Salvati, and Antonio Randazzo. "Targeting of telomeric repeat-containing RNA G-quadruplexes: From screening to biophysical and biological characterization of a new hit compound." In 7th International Electronic Conference on Medicinal Chemistry. Basel, Switzerland: MDPI, 2021. http://dx.doi.org/10.3390/ecmc2021-11382.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

3

Schmitz, Rebecca, Alex J. Walsh, Kelsey Tweed, Steven Trier, Anna Huttenlocher, and Melissa Skala. "Zebrafish xenograft breast cancer models for high-throughput drug response screening." In Biophysics, Biology and Biophotonics IV: the Crossroads, edited by Adam Wax and Vadim Backman. SPIE, 2019. http://dx.doi.org/10.1117/12.2513688.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

4

Tan, Qiyan, Weichuan Guo, Gutian Zhao, Yajing Kan, Yinghua Qiu, and Yunfei Chen. "Charge Inversion of Mica Surface in Multivalent Electrolytes." In ASME 2013 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/imece2013-62356.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Анотація:

Interaction between solid surfaces in aqueous electrolyte solutions is of great importance to many diverse domains, such as bioMEMS, nanofluidics, colloid science, polymer physics, and molecular biophysics. Several counterintuitive phenomena occur at high concentrations of multivalent ions. In this article, charge reversion, the sign reversal of the effective surface charge in the presence of multivalent counterions, is directly observed through the force between two mica surfaces in aqueous solutions of trivalent cations by surface forces measurements. The effective surface potential functioned with bulk concentration is calculated from an analytical model based on ion correlations. The obtained force profiles can be described by the analytical model when ion correlations effects are taken into account, while Poisson-Boltzmann theory fails. It reveals that ion correlations are important for screening charged surface in the presence of multivalent counterions.