981 resultados para Biased Agonist


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Despite the well-established antitumor activity of CD1d-restricted invariant natural killer T lymphocytes (iNKT), their use for cancer therapy has remained challenging. This appears to be due to their strong but short-lived activation followed by long-term anergy after a single administration of the CD1d agonist ligand alpha-galactosylceramide (αGC). As a promising alternative, we obtained sustained mouse iNKT cell responses associated with prolonged antitumor effects through repeated administrations of tumor-targeted recombinant sCD1d-antitumor scFv fusion proteins loaded with αGC. Here, we demonstrate that CD1d fusion proteins bound to tumor cells via the antibody fragment specific for a tumor-associated antigen, efficiently activate human iNKT cell lines leading to potent tumor cell lysis. The importance of CD1d tumor targeting was confirmed in tumor-bearing mice in which only the specific tumor-targeted CD1d fusion protein resulted in tumor inhibition of well-established aggressive tumor grafts. The therapeutic efficacy correlated with the repeated activation of iNKT and natural killer cells marked by their release of TH1 cytokines, despite the up-regulation of the co-inhibitory receptor PD-1. Our results demonstrate the superiority of providing the superagonist αGC loaded on recombinant CD1d proteins and support the use of αGC/sCD1d-antitumor fusion proteins to secure a sustained human and mouse iNKT cell activation, while targeting their cytotoxic activity and cytokine release to the tumor site.

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Les catastrophes sont souvent perçues comme des événements rapides et aléatoires. Si les déclencheurs peuvent être soudains, les catastrophes, elles, sont le résultat d'une accumulation des conséquences d'actions et de décisions inappropriées ainsi que du changement global. Pour modifier cette perception du risque, des outils de sensibilisation sont nécessaires. Des méthodes quantitatives ont été développées et ont permis d'identifier la distribution et les facteurs sous- jacents du risque.¦Le risque de catastrophes résulte de l'intersection entre aléas, exposition et vulnérabilité. La fréquence et l'intensité des aléas peuvent être influencées par le changement climatique ou le déclin des écosystèmes, la croissance démographique augmente l'exposition, alors que l'évolution du niveau de développement affecte la vulnérabilité. Chacune de ses composantes pouvant changer, le risque est dynamique et doit être réévalué périodiquement par les gouvernements, les assurances ou les agences de développement. Au niveau global, ces analyses sont souvent effectuées à l'aide de base de données sur les pertes enregistrées. Nos résultats montrent que celles-ci sont susceptibles d'être biaisées notamment par l'amélioration de l'accès à l'information. Elles ne sont pas exhaustives et ne donnent pas d'information sur l'exposition, l'intensité ou la vulnérabilité. Une nouvelle approche, indépendante des pertes reportées, est donc nécessaire.¦Les recherches présentées ici ont été mandatées par les Nations Unies et par des agences oeuvrant dans le développement et l'environnement (PNUD, l'UNISDR, la GTZ, le PNUE ou l'UICN). Ces organismes avaient besoin d'une évaluation quantitative sur les facteurs sous-jacents du risque, afin de sensibiliser les décideurs et pour la priorisation des projets de réduction des risques de désastres.¦La méthode est basée sur les systèmes d'information géographique, la télédétection, les bases de données et l'analyse statistique. Une importante quantité de données (1,7 Tb) et plusieurs milliers d'heures de calculs ont été nécessaires. Un modèle de risque global a été élaboré pour révéler la distribution des aléas, de l'exposition et des risques, ainsi que pour l'identification des facteurs de risque sous- jacent de plusieurs aléas (inondations, cyclones tropicaux, séismes et glissements de terrain). Deux indexes de risque multiples ont été générés pour comparer les pays. Les résultats incluent une évaluation du rôle de l'intensité de l'aléa, de l'exposition, de la pauvreté, de la gouvernance dans la configuration et les tendances du risque. Il apparaît que les facteurs de vulnérabilité changent en fonction du type d'aléa, et contrairement à l'exposition, leur poids décroît quand l'intensité augmente.¦Au niveau local, la méthode a été testée pour mettre en évidence l'influence du changement climatique et du déclin des écosystèmes sur l'aléa. Dans le nord du Pakistan, la déforestation induit une augmentation de la susceptibilité des glissements de terrain. Les recherches menées au Pérou (à base d'imagerie satellitaire et de collecte de données au sol) révèlent un retrait glaciaire rapide et donnent une évaluation du volume de glace restante ainsi que des scénarios sur l'évolution possible.¦Ces résultats ont été présentés à des publics différents, notamment en face de 160 gouvernements. Les résultats et les données générées sont accessibles en ligne (http://preview.grid.unep.ch). La méthode est flexible et facilement transposable à des échelles et problématiques différentes, offrant de bonnes perspectives pour l'adaptation à d'autres domaines de recherche.¦La caractérisation du risque au niveau global et l'identification du rôle des écosystèmes dans le risque de catastrophe est en plein développement. Ces recherches ont révélés de nombreux défis, certains ont été résolus, d'autres sont restés des limitations. Cependant, il apparaît clairement que le niveau de développement configure line grande partie des risques de catastrophes. La dynamique du risque est gouvernée principalement par le changement global.¦Disasters are often perceived as fast and random events. If the triggers may be sudden, disasters are the result of an accumulation of actions, consequences from inappropriate decisions and from global change. To modify this perception of risk, advocacy tools are needed. Quantitative methods have been developed to identify the distribution and the underlying factors of risk.¦Disaster risk is resulting from the intersection of hazards, exposure and vulnerability. The frequency and intensity of hazards can be influenced by climate change or by the decline of ecosystems. Population growth increases the exposure, while changes in the level of development affect the vulnerability. Given that each of its components may change, the risk is dynamic and should be reviewed periodically by governments, insurance companies or development agencies. At the global level, these analyses are often performed using databases on reported losses. Our results show that these are likely to be biased in particular by improvements in access to information. International losses databases are not exhaustive and do not give information on exposure, the intensity or vulnerability. A new approach, independent of reported losses, is necessary.¦The researches presented here have been mandated by the United Nations and agencies working in the development and the environment (UNDP, UNISDR, GTZ, UNEP and IUCN). These organizations needed a quantitative assessment of the underlying factors of risk, to raise awareness amongst policymakers and to prioritize disaster risk reduction projects.¦The method is based on geographic information systems, remote sensing, databases and statistical analysis. It required a large amount of data (1.7 Tb of data on both the physical environment and socio-economic parameters) and several thousand hours of processing were necessary. A comprehensive risk model was developed to reveal the distribution of hazards, exposure and risk, and to identify underlying risk factors. These were performed for several hazards (e.g. floods, tropical cyclones, earthquakes and landslides). Two different multiple risk indexes were generated to compare countries. The results include an evaluation of the role of the intensity of the hazard, exposure, poverty, governance in the pattern and trends of risk. It appears that the vulnerability factors change depending on the type of hazard, and contrary to the exposure, their weight decreases as the intensity increases.¦Locally, the method was tested to highlight the influence of climate change and the ecosystems decline on the hazard. In northern Pakistan, deforestation exacerbates the susceptibility of landslides. Researches in Peru (based on satellite imagery and ground data collection) revealed a rapid glacier retreat and give an assessment of the remaining ice volume as well as scenarios of possible evolution.¦These results were presented to different audiences, including in front of 160 governments. The results and data generated are made available online through an open source SDI (http://preview.grid.unep.ch). The method is flexible and easily transferable to different scales and issues, with good prospects for adaptation to other research areas. The risk characterization at a global level and identifying the role of ecosystems in disaster risk is booming. These researches have revealed many challenges, some were resolved, while others remained limitations. However, it is clear that the level of development, and more over, unsustainable development, configures a large part of disaster risk and that the dynamics of risk is primarily governed by global change.

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Les cancers du col utérin et de la vessie prennent tous deux leur origine dans les sites muqueux et peuvent évoluer lentement de lésions superficielles (lésions squameuses intra-épithéliales de bas à haut grade (HSIL) et carcinomes in situ du col utérin (CIS); ou tumeurs non musculo-invasives de la vessie (NMIBC)) à des cancers invasifs plus avancés. L'éthiologie de ces deux cancers est néanmoins très différente. Le cancer du col utérin est, à l'échelle mondiale, le deuxième cancer le plus mortel chez la femme. Ce cancer résulte de l'infection des cellules basales de l'épithélium stratifié du col utérin par le papillomavirus humain à haut risque (HPV). Les vaccins prophylactiques récemment développés contre le HPV (Gardasil® et Cervarix®) sont des moyens de prévention efficaces lorsqu'ils sont administrés chez les jeunes filles qui ne sont pas encore sexuellement actives; cependant ces vaccins ne permettent pas la régression des lésions déjà existantes. Malgré un développement actif, les vaccins thérapeutiques ciblant les oncogènes viraux E6/E7 n'ont montré qu'une faible efficacité clinique jusqu'à présent. Nous avons récemment démontré qu'une immunisation sous-cutanée (s.c.) était capable de faire régresser les petites tumeurs génitales chez 90% des souris, mais chez seulement 20% des souris présentant de plus grandes tumeurs. Dans cette étude, nous avons développé une nouvelle stratégie où la vaccination est associée à une application locale (intra-vaginale (IVAG)) d'agonistes de TLR. Celle-ci induit une augmentation des cellules T CD8 totales ainsi que T CD8 spécifiques au vaccin, mais pas des cellules T CD4. L'attraction sélective des cellules T CD8 est permise par leur expression des récepteurs de chemokines CCR5 et CXCR3 ainsi que par les ligants E-selectin. La vaccination, suivie de l'application IVAG de CpG, a conduit, chez 75% des souris, à la régression de grandes tumeurs établies. Le cancer de la vessie est le deuxième cancer urologique le plus fréquente. La plupart des tumeurs sont diagnostiquées comme NMIBC et sont restreintes à la muqueuse de la vessie, avec une forte propension à la récurrence et/ou progression après une résection locale. Afin de développer des vaccins contre les antigènes associés à la tumeur (TAA), il est nécessaire de trouver un moyen d'induire une réponse immunitaire CD8 spécifique dans la vessie. Pour ce faire, nous avons comparé différentes voies d'immunisation, en utilisant un vaccin composé d'adjuvants et de l'oncogène de HPV (E7) comme modèle. Les vaccinations s.c. et IVAG ont toutes deux induit un nombre similaire de cellules T CD8 spécifiques du vaccin dans la vessie, alors que l'immunisation intra-nasale fut inefficace. Les voies s.c. et IVAG ont induit des cellules T CD8 spécifiques du vaccin exprimant principalement aL-, a4- et le ligand d'E-selectin, suggérant que ces intégrines/sélectines sont responsables de la relocalisation des cellules T dans la vessie. Une unique immunisation avec E7 a permis une protection tumorale complète lors d'une étude prophylactique, indépendemment de la voie d'immunisation. Dans une étude thérapeutique, seules les vaccinations s.c. et IVAG ont efficacement conduit, chez environ 50% des souris, à la régression de tumeurs de la vessie établies, alors que l'immunisation intra-nasale n'a eu aucun effet. La régression de la tumeur est correlée avec l'infiltration dans la tumeur des cellules T CD8 spécifiques au vaccin et la diminution des cellules T régulatrices (Tregs). Afin d'augmenter l'efficacité de l'immunisation avec le TAA, nous avons testé une vaccination suivie de l'instillation d'agonistes de TLR3 et TLR9, ou d'un vaccin Salmonella Typhi (Ty21a). Cette stratégie a entraîné une augmentation des cellules T CD8 effectrices spécifiques du vaccin dans la vessie, bien qu'à différentes échelles. Ty21a étant l'immunostimulant le plus efficace, il mérite d'être étudié de manière plus approfondie dans le contexte du NMIBC. - Both cervical and bladder cancer originates in mucosal sites and can slowly progress from superficial lesions (low to high-grade squamous intra-epithelial lesions (HSIL) and carcinoma in situ (CIS) in the cervix; or non-muscle invasive tumors in the bladder (NMIBC)), to more advanced invasive cancers. The etiology of these two cancers is however very different. Cervical cancer is the second most common cause of cancer death in women worldwide. This cancer results from the infection of the basal cells of the stratified epithelium of the cervix by high-risk human papillomavirus (HPV). The recent availability of prophylactic vaccines (Gardasil® and Cervarix®) against HPV is an effective strategy to prevent this cancer when administered to young girls before sexual activity; however, these vaccines do not induce regression of established lesions. Despite active development, therapeutic vaccines targeting viral oncogenes E6/E7 had limited clinical efficacy to date. We recently reported that subcutaneous (s.c.) immunization was able to regress small genital tumors in 90% of the mice, but only 20% of mice had regression of larger tumors. Here, we developed a new strategy where vaccination is combined with the local (intravaginal (IVAG)) application of TLR agonists. This new strategy induced an increase of both total and vaccine-specific CD8 T cells in cervix-vagina, but not CD4 T cells. The selective attraction of CD8 T cells is mediated by the expression of CCR5 and CXCR3 chemokine receptors and E-selectin ligands in these cells. Vaccination followed by IVAG application of CpG resulted in tumor regression of large established tumors in 75% of the mice. Bladder cancer is the second most common urological malignancy. Most tumors are diagnosed as NMIBC, and are restricted to the mucosal bladder with a high propensity to recur and/or progress after local resection. Aiming to develop vaccines against tumor associated antigens (TAA) it is necessary to investigate how to target vaccine-specific T-cell immune responses to the bladder. Here we thus compared using an adjuvanted HPV oncogene (E7) vaccine, as a model, different routes of immunization. Both s.c. and IVAG vaccination induced similar number of vaccine-specific CD8 T-cells in the bladder, whereas intranasal (i.n.) immunization was ineffective. S.c. and IVAG routes induced predominantly aL-, a4- and E-selectin ligand-expressing vaccine-specific CD8 T-cells suggesting that these integrin/selectin are responsible for T-cell homing to the bladder. A single E7 immunization conferred full tumor protection in a prophylactic setting, irrespective of the immunization route. In a therapeutic setting, only ivag and s.c. vaccination efficiently regressed established bladder-tumors in ca. 50 % of mice, whereas i.n. immunization had no effect. Tumor regression correlated with vaccine- specific CD8 T cell tumor-infiltration and decrease of regulatory T cells (Tregs). To increase efficacy of TAA immunization, we tested vaccination followed by the local instillation of TLR3 or TLR9 agonist or of a Salmonella Typhi vaccine (Ty21a). This strategy resulted in an increase of vaccine-specific effector CD8 T cells in the bladder, although at different magnitudes. Ty21a being the most efficient, it deserves further investigation in the context of NMIBC. We further tested another strategy to improve therapies of NMIBC. In the murine MB49 bladder tumor model, we replaced the intravesical (ives) BCG therapy by another vaccine strain the Salmonella Ty21a. Ives Ty21a induced bladder tumor regression at least as efficiently as BCG. Ty21a bacteria did not infect nor survive neither in healthy nor in tumor-bearing bladders, suggesting its safety. Moreover, Ty21a induced a transient inflammatory response in healthy bladders, mainly through infiltration of neutrophils and macrophages that rapidly returned to basal levels, confirming its potential safety. The tumor regression was associated to a robust infiltration of immune cells, and secretion of cytokines in urines. Infection of murine tumor cell lines by Ty21a resulted in cell apoptosis. The infection of both murine and human urothelial cell lines induced secretion of in vitro inflammatory cytokines. Ty21a may be an attractive alternative for the ives treatment of NMIBC after transurethral resection and thus deserves more investigation.

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The GABAergic system modulates respiratory activity and undergoes substantial changes during early life. Because this maturation process is sensitive to stress, we tested the hypothesis that gestational stress (GS) alters development of GABAergic modulation of respiratory control in rat pups. The respiratory responses to the selective GABAA receptor agonist muscimol were compared between pups born to dams subjected to GS (bright light and predator odor; 20 min/day from G9 to G19) or maintained under standard (control) conditions. Respiratory activity was measured on 1 and 4 days old pups of both sexes using in vivo (whole body plethysmography) and in vitro (isolated brainstem-spinal cord preparation) approaches. In intact pups, muscimol injection (0.75 mg/kg; i.p.) depressed minute ventilation; this response was less in GS pups, and at P4, muscimol augmented minute ventilation in GS females. Bath application of muscimol (0.01-0.5 μM) onto brainstem preparations decreased inspiratory (C4) burst frequency and amplitude in a dose-dependent manner; the responsiveness decreased with age. However, GS had limited effects on these results. We conclude that the results obtained in vivo are consistent with our hypothesis and show that GS delays maturation of GABAergic modulation of respiratory activity. The differences in the results observed between experimental approaches (in vivo versus in vitro) indicate that the effect of prenatal stress on maturation of GABAergic modulation of respiratory control mainly affects the peripheral/metabolic components of the respiratory control system.

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Recent literature has discussed the unintended consequences of clinical information technologies (IT) on patient safety, yet there has been little discussion about the safety concerns in the area of consumer health IT. This paper presents a range of safety concerns for consumers in social media, with a case study on YouTube. We conducted a scan of abstracts on 'quality criteria' related to YouTube. Five areas regarding the safety of YouTube for consumers were identifi ed: (a) harmful health material targeted at consumers (such as inappropriate marketing of tobaccoor direct-to-consumer drug advertising); (b) public display of unhealthy behaviour (such as people displaying self-injury behaviours or hurting others); (c) tainted public health messages (i.e. the rise of negative voices againstpublic health messages); (d) psychological impact from accessing inappropriate, offensive or biased social media content; and (e) using social media to distort policy and research funding agendas. The examples presented should contribute to a better understanding about how to promote a safe consumption and production of social media for consumers, and an evidence-based approach to designing social media interventions for health. The potential harm associated with the use of unsafe social media content on the Internet is a major concern. More empirical and theoretical studies are needed to examine how social media infl uences consumer health decisions, behaviours and outcomes, and devise ways to deter the dissemination of harmful infl uences in social media.

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ABSTRACT: BACKGROUND: Local Mate Competition (LMC) theory predicts a female should produce a more female-biased sex ratio if her sons compete with each other for mates. Because it provides quantitative predictions that can be experimentally tested, LMC is a textbook example of the predictive power of evolutionary theory. A limitation of many earlier studies in the field is that the population structure and mating system of the studied species are often estimated only indirectly. Here we use microsatellites to characterize the levels of inbreeding of the bark beetle Xylosandrus germanus, a species where the level of LMC is expected to be high. RESULTS: For three populations studied, genetic variation for our genetic markers was very low, indicative of an extremely high level of inbreeding (FIS = 0.88). There was also strong linkage disequilibrium between microsatellite loci and a very strong genetic differentiation between populations. The data suggest that matings among non-siblings are very rare (3%), although sex ratios from X. germanus in both the field and the laboratory have suggested more matings between non-sibs, and so less intense LMC. CONCLUSIONS: Our results confirm that caution is needed when inferring mating systems from sex ratio data, especially when a lack of biological detail means the use of overly simple forms of the model of interest.

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Using the yeast two-hybrid system, we identified the mu 2 subunit of the clathrin adaptor complex 2 as a protein interacting with the C-tail of the alpha 1b-adrenergic receptor (AR). Direct association between the alpha 1b-AR and mu 2 was demonstrated using a solid phase overlay assay. The alpha 1b-AR/mu 2 interaction occurred inside the cells, as shown by the finding that the transfected alpha 1b-AR and the endogenous mu 2 could be coimmunoprecipitated from HEK-293 cell extracts. Mutational analysis of the alpha 1b-AR revealed that the binding site for mu 2 does not involve canonical YXX Phi or dileucine motifs but a stretch of eight arginines on the receptor C-tail. The binding domain of mu 2 for the receptor C-tail involves both its N terminus and the subdomain B of its C-terminal portion. The alpha 1b-AR specifically interacted with mu 2, but not with the mu 1, mu 3, or mu 4 subunits belonging to other AP complexes. The deletion of the mu 2 binding site in the C-tail markedly decreased agonist-induced receptor internalization as demonstrated by confocal microscopy as well as by the results of a surface receptor biotinylation assay. The direct association of the adaptor complex 2 with a G protein-coupled receptor has not been reported so far and might represent a common mechanism underlying clathrin-mediated receptor endocytosis.

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CD8+ cytotoxic T lymphocyte (CTL) can recognize and kill target cells that express only a few cognate major histocompatibility complex class I-peptide (pMHC) complexes. To better understand the molecular basis of this sensitive recognition process, we studied dimeric pMHC complexes containing linkers of different lengths. Although dimers containing short (10-30-A) linkers efficiently bound to and triggered intracellular calcium mobilization and phosphorylation in cloned CTL, dimers containing long linkers (> or = 80 A) did not. Based on this and on fluorescence resonance energy transfer experiments, we describe a dimeric binding mode in which two T cell receptors engage in an anti-parallel fashion two pMHC complexes facing each other with their constant domains. This binding mode allows integration of diverse low affinity interactions, which increases the overall binding and, hence, the sensitivity of antigen recognition. In proof of this, we demonstrated that pMHC dimers containing one agonist and one null ligand efficiently activate CTL, corroborating the importance of endogenous pMHC complexes in antigen recognition.

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β-blockers and β-agonists are primarily used to treat cardiovascular diseases. Inter-individual variability in response to both drug classes is well recognized, yet the identity and relative contribution of the genetic players involved are poorly understood. This work is the first genome-wide association study (GWAS) addressing the values and susceptibility of cardiovascular-related traits to a selective β(1)-blocker, Atenolol (ate), and a β-agonist, Isoproterenol (iso). The phenotypic dataset consisted of 27 highly heritable traits, each measured across 22 inbred mouse strains and four pharmacological conditions. The genotypic panel comprised 79922 informative SNPs of the mouse HapMap resource. Associations were mapped by Efficient Mixed Model Association (EMMA), a method that corrects for the population structure and genetic relatedness of the various strains. A total of 205 separate genome-wide scans were analyzed. The most significant hits include three candidate loci related to cardiac and body weight, three loci for electrocardiographic (ECG) values, two loci for the susceptibility of atrial weight index to iso, four loci for the susceptibility of systolic blood pressure (SBP) to perturbations of the β-adrenergic system, and one locus for the responsiveness of QTc (p<10(-8)). An additional 60 loci were suggestive for one or the other of the 27 traits, while 46 others were suggestive for one or the other drug effects (p<10(-6)). Most hits tagged unexpected regions, yet at least two loci for the susceptibility of SBP to β-adrenergic drugs pointed at members of the hypothalamic-pituitary-thyroid axis. Loci for cardiac-related traits were preferentially enriched in genes expressed in the heart, while 23% of the testable loci were replicated with datasets of the Mouse Phenome Database (MPD). Altogether these data and validation tests indicate that the mapped loci are relevant to the traits and responses studied.

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The mass media are assigned an important role in political campaigns on popular votes. This article asks how the press communicates political issues to citizens during referendum campaigns, and whether some minimal criteria for successful public deliberation are met. The press coverage of all 24 ballot votes on welfare state issues from 1995 to 2004 in Switzerland is examined, distinguishing seven criteria to judge how news coverage compares to idealized notions of the media's role in the democratic process: coverage intensity, time for public deliberation, balance in media coverage, source independence and inclusiveness, substantive coverage, and spatial homogeneity. The results of our quantitative analysis suggest that the press does fulfil these normative requirements to a reasonable extent and that fears about biased or deceitful media treatment of ballot issues are not well-founded. However, some potential for optimizing the coverage of referendum campaigns by the Swiss press does exist

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OBJECTIVE: The aim of this study was to examine the differences between those who gave informed consent to a study on substance use and those who did not, and to analyze whether differences changed with varying nonconsent rates. METHOD: Cross-sectional questionnaire data on demographics, alcohol, smoking, and cannabis use were obtained for 6,099 French- and 5,720 German-speaking 20-year-old Swiss men. Enrollment took place over 11 months for the Cohort Study on Substance Use Risk Factors (C-SURF). Consenters and nonconsenters were asked to complete a short questionnaire. Data for nearly the entire population were available because 94% responded. Weekly differences in consent rates were analyzed. Regressions examined the associations of substance use with consent giving and consent rates and the interaction between the two. RESULTS: Nonconsenters had higher substance use patterns, although they were more often alcohol abstainers; differences were small and not always significant and did not decrease as consent rates increased. CONCLUSIONS: Substance use currently is a minor sensitive topic among young men, resulting in small differences between nonconsenters and consenters. As consent rates increase, additional individuals are similar to those observed at lower consent rates. Estimates of analytical studies looking at associations of substance use with other variables will not differ at reasonable consent rates of 50%-80%. Descriptive prevalence studies may be biased, but only at very low rates of consent.

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Introduction: The pharmaceutical aspects of drug administration in clinical trials receive poor consideration compared with the important attention devoted to the analytical and mathematical aspects of biological sample exploitation. During PK calculations, many researchers merely use for dose the nominal amount declared, overlooking the noticeable biases that may result in the assessment of PK parameters. The aim of this work was to evaluate the biases related to doses injected of a biosimilar drug in 2 Phase I clinical trials. Patients (or Materials) and Methods: In trial A, 12 healthy volunteers received different doses of a biosimilar of interferon beta-1a by either subcutaneous (SC) or intravenous (IV) injection. The doses were prepared by partially emptying 0.5-mL syringes supplied by the manufacturer (drop count procedure). In trial B, 12 healthy volunteers received 3 different formulations of the drug by IV injection (biosimilar without albumin [HSA], biosimilar with HSA and original brand [Rebif®]) and 2 different formulations as multiple SC injections (biosimilar HSA-free and original brand). In both trials, the actual dose administered was calculated as: D = C·V - losses. The product titer C was assessed by ELISA. The volume administered IV was assessed by weighting. Losses were evaluated by in vitro experiments. Finally, the binding of 125I-interferon to HSA was evaluated by counting the free and HSA complexed molecule fractions separated by gel filtration. Results: Interferon was not significantly adsorbed onto the lines used for its IV administration. In trial A, the titer was very close to the one declared (96 ± 7%). In trial B, it differed significantly (156 ± 10% for biosimilar with/without HSA and 123 ± 5% for original formulation). In trial A, the dose actually administered showed a large variability. The real injected volume could be biased up to 75% compared with the theoretical volume (for the lower dose administered [ie, 0.03 mL]). This was mainly attributed to a partial re-aspiration of the drug solution before withdrawing the syringe needle. A strict procedure was therefore applied in trial B to avoid these inaccuracies. Finally, in trial B, 125I-Interferon beta-1a binding to HSA appeared time dependent and slow, reaching 50% after 16-hour incubation, which is close to steady state reported for the comparator Rebif®. Conclusion: These practical examples (especially biases on actual titer and volume injected) illustrate that actual dose assessment deserves attention to ensure accuracy for estimates of clearance and distribution volume in the scientific literature and for registration purposes, especially for bioequivalence studies.

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Spodoptera frugiperda is a pest of great economic importance in the Americas. It is attacked by several species of parasitoids, which act as biological control agents. Parasitoids are morphologically identifiable as adults, but not as larvae. Laboratory rearing conditions are not always optimal to rear out parasitic wasps from S. frugiperda larvae collected from wild populations, and it frequently happens that parasitoids do not complete their life cycle and stop developing at the larval stage. Therefore, we explored ways to identify parasitoid larvae using molecular techniques. Sequencing is one possible technique, yet it is expensive. Here we present an alternate, cheaper way of identifying seven species of parasitoids (Cotesia marginiventris, Campoletis sonorensis, Pristomerus spinator, Chelonus insularis, Chelonus cautus, Eiphosoma vitticolle and Meteorus laphygmae) using PCR amplification of COI gene followed by a digestion with a combination of four restriction endonucleases. Each species was found to exhibit a specific pattern when the amplification product was run on an agarose gel. Identifying larvae revealed that conclusions on species composition of a population of parasitic wasps can be biased if only the emerging adults are taken into account.

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OBJECTIVE: Atrial natriuretic peptide (ANP) is a secretory hormone displaying diuretic, natriuretic, and vasorelaxant activities. Recently, its lipolytic activity has been reported. Since the expression of ANP in adipose tissue has not been documented, we used real-time reverse transcriptase polymerase chain reaction (RT-PCR) to investigate the expression of ANP in human adipose tissue and preadipocytes. RESEARCH METHODS AND PROCEDURES: RNA was extracted from the human adipose tissue of severely obese premenopausal women as well as from human preadipocytes. For human preadipocytes, two cell systems were investigated: the human preadipose immortalized (Chub-S7) cells, a well-characterized human preadipose cell line, and primary preadipocytes derived from the stromal vascular fraction of the human adipose tissue. We measured the mRNA of ANP, of corin (a transmembrane serine protease involved in the conversion of pro-ANP to ANP) and of uncoupling protein 2 (UCP2; a control gene known to be ubiquitously expressed). The expression of ANP was also investigated using immunofluorescence and radioimmunoassay in Chub-S7 cells and human primary preadipocytes in culture. RESULTS: Our results indicate that ANP and corin are expressed at the mRNA level in human adipose tissue and preadipocytes. Immunofluorescence experiments demonstrated that pro-ANP was expressed in Chub-S7 cells. In addition, ANP secretion could be measured in Chub-S7 cells and human primary preadipocytes in culture. Rosiglitazone, a selective peroxisome proliferator-activated receptor type gamma (PPAR-gamma) agonist promoting adipocyte differentiation, was found to modulate both ANP expression and secretion in preadipocytes. DISCUSSION: Our findings suggest the existence of an autocrine/paracrine system for ANP in the human adipose tissue whose implications in lipolysis and cardiovascular function need to be further explored.

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Toll-like receptors (TLRs) are pattern recognition receptors playing a fundamental role in sensing microbial invasion and initiating innate and adaptive immune responses. TLRs are also triggered by danger signals released by injured or stressed cells during sepsis. Here we focus on studies developing TLR agonists and antagonists for the treatment of infectious diseases and sepsis. Positioned at the cell surface, TLR4 is essential for sensing lipopolysaccharide of Gram-negative bacteria, TLR2 is involved in the recognition of a large panel of microbial ligands, while TLR5 recognizes flagellin. Endosomal TLR3, TLR7, TLR8, TLR9 are specialized in the sensing of nucleic acids produced notably during viral infections. TLR4 and TLR2 are favorite targets for developing anti-sepsis drugs, and antagonistic compounds have shown efficient protection from septic shock in pre-clinical models. Results from clinical trials evaluating anti-TLR4 and anti-TLR2 approaches are presented, discussing the challenges of study design in sepsis and future exploitation of these agents in infectious diseases. We also report results from studies suggesting that the TLR5 agonist flagellin may protect from infections of the gastrointestinal tract and that agonists of endosomal TLRs are very promising for treating chronic viral infections. Altogether, TLR-targeted therapies have a strong potential for prevention and intervention in infectious diseases, notably sepsis.