200 research outputs found
Prevention of HIV/AIDS on the Home Front: Lessons Learned from our Global Neighbors
The Human Immunodeficiency Virus, or HIV, epidemic represents one of the greatest public health challenges of the late 20th and now, early 21st century. According to the World Health Organization (2013), approximately 70 million people have been infected with HIV worldwide since the beginning of the epidemic and approximately 35 million people have perished. To date, great strides have been made therapeutically in the creation and distribution of HIV antiretrovirals (ARVs) that can keep viral levels low in the infected individual thus prolonging his/her life expectancy; however, in the absence of an effective vaccine, prevention still is the most viable method of combating the pandemic. As the greatest burden of the epidemic lies outside the United States, there have been a plethora of prevention programs that have been launched internationally to combat HIV infection. Programs offering voluntary counseling and testing, condom distribution, needle/syringe exchange, and antiretroviral distribution have shown success in reducing HIV incidence in a wide range of geographic locations, including developing countries, where they have been launched. While many of the concepts of the programs are not new to the United States; to date, most prevention efforts have been sporadic and focused at the state or local level as opposed to federally-funded, evidence-based prevention programs on a national scale. Utilizing information gleaned from other countries, and especially developing countries, a series of recommendations are presented for how to improve HIV prevention efforts in the United States. Barriers to implementation of these ideas are also discussed and methods to overcome these barriers are presented, including social marketing, a field of study and practice that can be potentially utilized to launch prevention efforts in the communities of individuals that are most at risk.Master of Public Healt
International Technology Transfer of a GCLP-Compliant HIV-1 Neutralizing Antibody Assay for Human Clinical Trials
The Collaboration for AIDS Vaccine Discovery/Comprehensive Antibody – Vaccine Immune Monitoring Consortium (CAVD/CA-VIMC) assisted an international network of laboratories in transferring a validated assay used to judge HIV-1 vaccine immunogenicity in compliance with Good Clinical Laboratory Practice (GCLP) with the goal of adding quality to the conduct of endpoint assays for Human Immunodeficiency Virus I (HIV-1) vaccine human clinical trials. Eight Regional Laboratories in the international setting (Regional Laboratories), many located in regions where the HIV-1 epidemic is most prominent, were selected to implement the standardized, GCLP-compliant Neutralizing Antibody Assay for HIV-1 in TZM-bl Cells (TZM-bl NAb Assay). Each laboratory was required to undergo initial training and implementation of the immunologic assay on-site and then perform partial assay re-validation, competency testing, and undergo formal external audits for GCLP compliance. Furthermore, using a newly established external proficiency testing program for the TZM-bl NAb Assay has allowed the Regional Laboratories to assess the comparability of assay results at their site with the results of neutralizing antibody assays performed around the world. As a result, several of the CAVD/CA-VIMC Regional Laboratories are now in the process of conducting or planning to conduct the GCLP-compliant TZM-bl NAb Assay as an indicator of vaccine immunogenicity for ongoing human clinical trials
500.05 Comparison Between Fractional Flow Reserve (FFR) vs. Computational Fractional Flow Reserve Derived from Three-dimensional Intravascular Ultrasound (IVUSFR) and Quantitative Flow Ratio (QFR)
BACKGROUND The determination of the ischemic status of a coronary artery by wireless physiologic assessment derived from angiography has been validated and approved in the US. However, the use ofplain angiography quantitative variables does not add much to thephysiology data since it has low correlation with fractional flowreserve (FFR) and predicts clinical outcomes poorly. Recently, a grayscale intravascular ultrasound (IVUS) derived physiology method(IVUSFR) was developed and showed a good correlation with invasiveFFR by combining the geometric advantages of IVUS with physiology.The aim of this study is to assess the coefficient of correlation (R) ofinvasive FFR compared to IVUSFR and quantitative flow ratio (QFR).METHODS Stable coronary artery disease (CAD) patients with intermediate lesions (i.e. 40?80% of diameter stenosis) were assessed by angiography and IVUS. QFR was derived from the angiography images, andIVUSFR was derived from quantitative IVUS data using computationalfluid dynamics. Coefficient of correlation (R) was used in this report.RESULTS Twenty-four patients with 34 lesions were included in theanalysis. The IVUSFR, invasive FFR, Vessel QFR fixed flow (vQFRf),and Vessel QFR contrast flow (vQFRc) values varied from 0.52 to 1.00,0.71 to 0.99, 0.55 to 1.00, and 0.34 to 1.00, respectively. The coefficient of correlation (R) of FFR vs. IVUSFR was 0.79; FFR vs. vQFRf was0.72; FFR vs. vQFRc was 0.65 (Figure).CONCLUSION Compared to invasive FFR, IVUSFR and vQFRf showed asimilar coefficient of correlation and were better than vQFR contrast flowFil: Kajita, Alexandre. Medstart; Estados UnidosFil: Bezerra, Cristiano Guedes. Universidade Federal da Bahia; BrasilFil: Ozaki, Yuichi. Medstart; Estados UnidosFil: Dan, Kazuhiro. Medstart; Estados UnidosFil: Melaku, Gebremedhin D.. Medstart; Estados UnidosFil: Pinton, Fabio A.. Universidade de Sao Paulo; BrasilFil: Falcão, Breno A. A.. Hospital of Messejana; BrasilFil: Mariani, José. Universidade de Sao Paulo; BrasilFil: Bulant, Carlos Alberto. Consejo Nacional de Investigaciones CientÃficas y Técnicas; Argentina. National Laboratory For Scientific Computing; BrasilFil: Maso Talou, Gonzalo Daniel. National Laboratory For Scientific Computing; BrasilFil: Esteves, Antonio. Universidade de Sao Paulo; BrasilFil: Blanco, Pablo Javier. National Laboratory For Scientific Computing; BrasilFil: Waksman, Ron. Medstart; Estados UnidosFil: Garcia Garcia, Hector M.. Medstart; Estados UnidosFil: Lemons, Pedro Alves. Universidade de Sao Paulo; Brasi
Fermi Large Area Telescope Constraints on the Gamma-ray Opacity of the Universe
The Extragalactic Background Light (EBL) includes photons with wavelengths
from ultraviolet to infrared, which are effective at attenuating gamma rays
with energy above ~10 GeV during propagation from sources at cosmological
distances. This results in a redshift- and energy-dependent attenuation of the
gamma-ray flux of extragalactic sources such as blazars and Gamma-Ray Bursts
(GRBs). The Large Area Telescope onboard Fermi detects a sample of gamma-ray
blazars with redshift up to z~3, and GRBs with redshift up to z~4.3. Using
photons above 10 GeV collected by Fermi over more than one year of observations
for these sources, we investigate the effect of gamma-ray flux attenuation by
the EBL. We place upper limits on the gamma-ray opacity of the Universe at
various energies and redshifts, and compare this with predictions from
well-known EBL models. We find that an EBL intensity in the optical-ultraviolet
wavelengths as great as predicted by the "baseline" model of Stecker et al.
(2006) can be ruled out with high confidence.Comment: 42 pages, 12 figures, accepted version (24 Aug.2010) for publication
in ApJ; Contact authors: A. Bouvier, A. Chen, S. Raino, S. Razzaque, A.
Reimer, L.C. Reye
Variation in dopamine D2 and serotonin 5-HT2A receptor genes is associated with working memory processing and response to treatment with antipsychotics
Dopamine D2 and serotonin 5-HT2A receptors contribute to modulate prefrontal cortical physiology and response to treatment with
antipsychotics in schizophrenia. Similarly, functional variation in the genes encoding these receptors is also associated with these
phenotypes. In particular, the DRD2 rs1076560 T allele predicts a lower ratio of expression of D2 short/long isoforms, suboptimal
working memory processing, and better response to antipsychotic treatment compared with the G allele. Furthermore, the HTR2A T
allele is associated with lower 5-HT2A expression, impaired working memory processing, and poorer response to antipsychotics
compared with the C allele. Here, we investigated in healthy subjects whether these functional polymorphisms have a combined effect
on prefrontal cortical physiology and related cognitive behavior linked to schizophrenia as well as on response to treatment with secondgeneration
antipsychotics in patients with schizophrenia. In a total sample of 620 healthy subjects, we found that subjects with the
rs1076560 T and rs6314 T alleles have greater fMRI prefrontal activity during working memory. Similar results were obtained within the
attentional domain. Also, the concomitant presence of the rs1076560 T/rs6314 T alleles also predicted lower behavioral accuracy during
working memory. Moreover, we found that rs1076560 T carrier/rs6314 CC individuals had better responses to antipsychotic treatment
in two independent samples of patients with schizophrenia (n¼63 and n¼54, respectively), consistent with the previously reported
separate effects of these genotypes. These results indicate that DRD2 and HTR2A genetic variants together modulate physiological
prefrontal efficiency during working memory and also modulate the response to antipsychotics. Therefore, these results suggest that
further exploration is needed to better understand the clinical consequences of these genotype–phenotype relationships
Wind, Waves, and Wing Loading: Morphological Specialization May Limit Range Expansion of Endangered Albatrosses
Among the varied adaptations for avian flight, the morphological traits allowing large-bodied albatrosses to capitalize on wind and wave energy for efficient long-distance flight are unparalleled. Consequently, the biogeographic distribution of most albatrosses is limited to the windiest oceanic regions on earth; however, exceptions exist. Species breeding in the North and Central Pacific Ocean (Phoebastria spp.) inhabit regions of lower wind speed and wave height than southern hemisphere genera, and have large intrageneric variation in body size and aerodynamic performance. Here, we test the hypothesis that regional wind and wave regimes explain observed differences in Phoebastria albatross morphology and we compare their aerodynamic performance to representatives from the other three genera of this globally distributed avian family. In the North and Central Pacific, two species (short-tailed P. albatrus and waved P. irrorata) are markedly larger, yet have the smallest breeding ranges near highly productive coastal upwelling systems. Short-tailed albatrosses, however, have 60% higher wing loading (weight per area of lift) compared to waved albatrosses. Indeed, calculated aerodynamic performance of waved albatrosses, the only tropical albatross species, is more similar to those of their smaller congeners (black-footed P. nigripes and Laysan P. immutabilis), which have relatively low wing loading and much larger foraging ranges that include central oceanic gyres of relatively low productivity. Globally, the aerodynamic performance of short-tailed and waved albatrosses are most anomalous for their body sizes, yet consistent with wind regimes within their breeding season foraging ranges. Our results are the first to integrate global wind and wave patterns with albatross aerodynamics, thereby identifying morphological specialization that may explain limited breeding ranges of two endangered albatross species. These results are further relevant to understanding past and potentially predicting future distributional limits of albatrosses globally, particularly with respect to climate change effects on basin-scale and regional wind fields
Framingham Heart Study 100K project: genome-wide associations for cardiovascular disease outcomes
BACKGROUND:Cardiovascular disease (CVD) and its most common
manifestations - including coronary heart disease (CHD), stroke, heart failure (HF), and
atrial fibrillation (AF) - are major causes of morbidity and mortality. In many
industrialized countries, cardiovascular disease (CVD) claims more lives each year than any
other disease. Heart disease and stroke are the first and third leading causes of death in
the United States. Prior investigations have reported several single gene variants
associated with CHD, stroke, HF, and AF. We report a community-based genome-wide association
study of major CVD outcomes.METHODS:In 1345 Framingham Heart Study participants from the
largest 310 pedigrees (54% women, mean age 33 years at entry), we analyzed associations of
70,987 qualifying SNPs (Affymetrix 100K GeneChip) to four major CVD outcomes: major
atherosclerotic CVD (n = 142; myocardial infarction, stroke, CHD death), major CHD (n = 118;
myocardial infarction, CHD death), AF (n = 151), and HF (n = 73). Participants free of the
condition at entry were included in proportional hazards models. We analyzed model-based
deviance residuals using generalized estimating equations to test associations between SNP
genotypes and traits in additive genetic models restricted to autosomal SNPs with minor
allele frequency [greater than or equal to]0.10, genotype call rate [greater than or equal
to]0.80, and Hardy-Weinberg equilibrium p-value [greater than or equal to] 0.001.RESULTS:Six
associations yielded p <10-5. The lowest p-values for each CVD trait were as follows:
major CVD, rs499818, p = 6.6 x 10-6; major CHD, rs2549513, p = 9.7 x 10-6; AF, rs958546, p =
4.8 x 10-6; HF: rs740363, p = 8.8 x 10-6. Of note, we found associations of a 13 Kb region
on chromosome 9p21 with major CVD (p 1.7 - 1.9 x 10-5) and major CHD (p 2.5 - 3.5 x 10-4)
that confirm associations with CHD in two recently reported genome-wide association studies.
Also, rs10501920 in CNTN5 was associated with AF (p = 9.4 x 10-6) and HF (p = 1.2 x 10-4).
Complete results for these phenotypes can be found at the dbgap website
http://www.ncbi.nlm.nih.gov/projects/gap/cgi-bin/study.cgi?id=phs000007.CONCLUSION:No
association attained genome-wide significance, but several intriguing findings emerged.
Notably, we replicated associations of chromosome 9p21 with major CVD. Additional studies
are needed to validate these results. Finding genetic variants associated with CVD may point
to novel disease pathways and identify potential targeted preventive therapies
Lower Expression of TLR2 and SOCS-3 Is Associated with Schistosoma haematobium Infection and with Lower Risk for Allergic Reactivity in Children Living in a Rural Area in Ghana
Inflammatory diseases such as atopic disorders are a major health problem in the Western world, but their prevalence is also increasing in developing countries, especially in urban centres. There is increasing evidence that exposure to a rural environment with high burden of compounds derived from parasites and microorganisms is associated with protection from atopic disorders. Since urbanisation is progressing at a rapid pace, particularly in less-developed nations, there is a need to understand the molecular processes that control the progress towards the development of allergic diseases in developing countries. In this study we have examined a population of school children living in a rural area of Ghana, where helminth (worm) infections are prevalent and associated with protection from skin reactivity to house dust mite. Blood samples were collected from these children and analysed for the expression levels of several genes involved in the development of a pro allergic immune system. The results point at a potential molecular link that might explain the negative association between schistosome infections and allergies
IL-21 and IL-6 Are Critical for Different Aspects of B Cell Immunity and Redundantly Induce Optimal Follicular Helper CD4 T Cell (Tfh) Differentiation
Cytokines are important modulators of lymphocytes, and both interleukin-21 (IL-21) and IL-6 have proposed roles in T follicular helper (Tfh) differentiation, and directly act on B cells. Here we investigated the absence of IL-6 alone, IL-21 alone, or the combined lack of IL-6 and IL-21 on Tfh differentiation and the development of B cell immunity in vivo. C57BL/6 or IL-21−/− mice were treated with a neutralizing monoclonal antibody against IL-6 throughout the course of an acute viral infection (lymphocytic choriomeningitis virus, LCMV). The combined absence of IL-6 and IL-21 resulted in reduced Tfh differentiation and reduced Bcl6 protein expression. In addition, we observed that these cytokines had a large impact on antigen-specific B cell responses. IL-6 and IL-21 collaborate in the acute T-dependent antiviral antibody response (90% loss of circulating antiviral IgG in the absence of both cytokines). In contrast, we observed reduced germinal center formation only in the absence of IL-21. Absence of IL-6 had no impact on germinal centers, and combined absence of both IL-21 and IL-6 revealed no synergistic effect on germinal center B cell development. Studying CD4 T cells in vitro, we found that high IL-21 production was not associated with high Bcl6 or CXCR5 expression. TCR stimulation of purified naïve CD4 T cells in the presence of IL-6 also did not result in Tfh differentiation, as determined by Bcl6 or CXCR5 protein expression. Cumulatively, our data indicates that optimal Tfh formation requires IL-21 and IL-6, and that cytokines alone are insufficient to drive Tfh differentiation
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