Search

Modern animal husbandry in the United States and other parts of the world has evolved the swine industry from one that was pasture based into a system based predominantly upon confinement and concentration of animals (Perez-Trallero and Zigorraga 1995; Scarpino and Quinn 1998). Most current animal production facilities rely on confined animal feeding operations (CAFOs) and the addition of subtherapeutic doses of broad-spectrum antibiotics to swine feed as a cheaper way to prevent disease and maintain production yields (Witte 1998). Antimicrobials are known to promote growth in swine and improve the efficiency of feed conversion and can affect bacterial and fungal disease prophylaxis among the confined animals (Davies and Roberts 1999). These treated animals generally gained weight 4–5% faster than other animals not given the antibiotics. Feeding animals antibiotics is associated with the development of antibiotic-resistant bacteria within these animals (Burriel 1997; Nijsten et al. 1996; Threlfall et al. 1993). Antibiotic use within food production animals has raised concern among public health authorities regarding the development of antibiotic-resistant bacteria in dosed animals and the possible subsequent impact on the health of farmworkers and others in proximity to the CAFOs (Witte 1998). Antibiotics are the leading treatment method for bacterial infectious diseases, which remain the most common cause of death worldwide (McGeer 1998). It is widely accepted that antibiotic-resistant pathogens make clinical treatment more difficult (Takafuji 1977). At local levels, areas surrounding swine production facilities might notice a rise in the difficulty of treating human health problems (Haglind and Rylander 1987). These health concerns include, but are not limited to, respiratory problems, infectious disease, and hypersensitive reactions (DuPont and Steele 1987). Those individuals who live or work in proximity to a facility spreading antibiotic-resistant bacteria could face higher exposures to these organisms (Scarpino and Quinn 1998). Gibbs et al. (2004) recovered antibiotic-resistant organisms known to have adverse human health effects both inside and downwind of the facility. It is an important next step to begin evaluating the distance these organisms can travel within bioaerosols to eventually address public health impact. The CAFO evaluated in this study was not using subtherapeutic doses of antibiotics at the time air sampling was conducted; however, the animals had received subtherapeutic levels of antibiotics 4 weeks before sampling. The primary objective of this study was to determine the levels of antibiotic-resistant bacteria, including multidrug-resistant bacteria (those resistant to at least two classes of antibiotics) found in air plumes 25 m upwind and 25, 50, 100, and 150 m downwind from a CAFO. These organisms could affect the health of those in proximity to the facility, such as employees. We hypothesized that the quantity of antibiotic-resistant bacteria would show a negative correlation with distance from the CAFO facility, which would support previous research showing that the animals within CAFOs are significant sources of antibiotic-resistant organisms (Gibbs et al. 2004).

Objective: To compare the viral genotypes present in RNA from brain and peripheral blood mononuclear cells (PBMC) and DNA from brain during acute, asymptomatic and late stages of SIV infection of macaques. Methods: Eighteen pigtailed macaques were intravenously inoculated with SIV. At 10, 21 and 56 days postinoculation, six were euthanized and the severity of encephalitis was assessed by microscopic examination. DNA and RNA were isolated from brain and PBMC, and the V1 region of env was amplified by the polymerase chain reaction and sequenced from over 800 different clones. Results: Similar genotypes were detected in RNA from brain and PBMC at 10 days postinoculation, suggesting an unrestricted exchange of virus between the periphery and the brain during acute infection. There was a progressive increase in the percentage of neurovirulent genotypes in brain RNA from acute (14% of all genotypes detected in brain RNA) to early asymptomatic (45%), to late asymptomatic (52%) and to terminal (95%) infection. Fewer different genotypes were found in brain RNA than in PBMC RNA from macaques euthanized during early asymptomatic (2.5 and 5 different genotypes, respectively; P = 0.007), late asymptomatic (2 and 5 different genotypes, respectively; P = 0.003) and terminal (2 and 4 different genotypes, respectively; P < 0.001) infection. Conclusion: These data demonstrate that the almost exclusive replication of neurovirulent genotypes in the brain seen at late-stage infection is a progressive process that begins early in infection and continues to late stage disease.

HIV testing and counseling has been associated with reductions in risk behaviors in some populations. This study examined whether involvement in a long-term study, including exposure to repeated HIV testing and counseling, was associated with increased condom use among injection drug users (IDUs) through a retrospective analysis of an IDU cohort from Baltimore, MD, during 1994-1998. Eligibility included being aged 18 years or older, injecting within 10 years and not having initiated antiretroviral therapy. A logistic model of high versus low risk, based on condom use, was used. Of 322 eligible IDUs, most were male (66%) and African-American (94%). No significant change in the odds of inconsistent condom use was observed with continued study exposure. Condom use remained low, indicating a need for interventions to reduce sexual risks and HIV transmission in this population.

Objectives: The objective of this research was to explore prenatal smoking behaviors among Black women attending prenatal clinics. Despite the racial disparities in poor pregnancy outcomes, and the well-known association of smoking with harmful outcomes, little research has been conducted about prenatal smoking among Black women. Methods: Women were enrolled in the study and interviewed at the time of the first prenatal visit. The interview contained items to assess prenatal smoking and cessation, depressive symptoms, demographic factors, and beliefs about smoking. Reports of smoking cessation were verified using urinary cotinine. Results: The sample consisted of 811 Black women. Fourteen percent of the women were self-reported smokers, 12.6% reported cessation and 73% were nonsmokers. Twenty percent of the self-reported quitters had elevated cotinine; when these women were reclassified, 17% of the women were smokers. Factors associated with smoking in logistic regression analysis included elevated maternal depressive symptoms (OR = 1.7, 95% CI: 1.1–2.6), maternal age 20 years or older (OR = 1.94; 95% CI: 1.1, 3.3), less than a high school education (OR = 2.2; 95% CI: 1.2, 3.8), unmarried/not living with a partner (OR = 1.9; 95% CI: 1.0, 3.6), and allowing smoking in the home (OR = 5.5; 95% CI: 3.4, 8.6). Conclusions: The prevalence of maternal prenatal smoking was much higher among women in this sample than has been previously reported. The rate of nondisclosure of smoking among self-reported quitters was also high. Maternal behavioral (allowing smoking in the home) and psychosocial factors (depressive symptoms) were associated with prenatal smoking.

We characterized factors and temporal trends associated with discontinuation of highly active antiretroviral therapy (HAART) among 936 HIV-infected women enrolled in the Women's Interagency HIV Study. A multivariate analysis of post-HAART initiation exposures found that high HIV RNA levels (relative hazard [RH] = 1.36, P < 0.001) and high depressive symptom scores (RH = 1.53, P = 0.012) were associated with HAART discontinuation. The adjusted hazard of discontinuation was higher in the 2 most recent calendar periods compared with the first (RH = 1.61, P = 0.026; RH = 1.56, P = 0.074, respectively). The increasing risk of HAART discontinuation in recent calendar periods and changes in the clinical factors associated with discontinuation reflect ongoing and dynamic shifts in the approach to HAART utilization.

Three-dimensional (3-D) bar graphs and their current 2-D alternatives have certain limitations when the primary objective is to provide an equal representation of the effects of two predictors on an outcome. This article proposes a graphing methodology (in the shape of a diamond) that projects 3-D bar graphs into 2-D whereby the third dimension is replaced with a polygon whose area and middle vertical and horizontal lengths represent the outcome. The proposed graphical representation is invariant to rotations and avoids outcomes in categories being concealed by others. This article shows several applications of our proposal to a variety of data types (e.g., proportions, incidence rates, relative risks), which can be easily implemented with available software.

Human immunodeficiency virus type 1 (HIV-1) currently infects ∼40 million people worldwide [1]. More than 95% of all new cases occur in developing countries, with heterosexual transmission being the predominant route of infection [1]. Rates of HIV-1 infection continue to increase, particularly among nonwhites and women [1]. In sub-Saharan Africa, a region that accounts for 70% of infected individuals globally, women with HIV-1 now outnumber men with HIV-1 [1]. Host differences may contribute to the rapid spread of HIV-1 in some areas of the world; specific genetic traits have been found to influence susceptibility to HIV-1 transmission and disease progression. In addition to CD4, the primary HIV-1 receptor, a functional secondary receptor is required to initiate infection. Human β-chemokine receptors serve this function, with CCR5 serving as coreceptor for macrophage-tropic strains of HIV-1 [2]. A 32-bp deletion (Δ32) in the CCR5 gene renders this receptor nonfunctional, and cells that are homozygous for this mutation are highly resistant to infection by macrophage-tropic strains of HIV-1 [3]. The mutation is most common in white populations, where the frequency of the Δ32 allele ranges from 4% to 16%; ∼20% of whites are heterozygous, and 1% are homozygous for Δ32 [4]. However, this allele is less common among US blacks and Latinas and was absent in Africans and Asian populations studied in anthropological surveys and investigations of non–HIV-related conditions [4]. Investigation of large cohorts of individuals exposed sexually or parenterally to HIV-1 found that the homozygous Δ32 mutation confers a high level of resistance to infection [5–8]. These studies, primarily composed of white men, also found that Δ32 heterozygotes exhibit delayed HIV-1 disease progression but were not protected against transmission [6–8]. However, a more recent study of high-risk HIV-1–seronegative men did demonstrate partial protection against HIV-1 infection in those with the Δ32 heterozygous genotype [9]. Because Δ32 heterozygotes of either sex express a reduced number of CCR5 receptors, compared with individuals with the wild-type genotype, the partial protection and delayed disease progression in heterozygotes may be related to the decreased number of CCR5 receptors and the resulting decreased virus load. Transmission studies involving women showed variable results; 2 studies suggested that the heterozygous state confers partial protection against HIV-1 infection [5, 10], whereas 3 other studies did not [9, 11, 12]. However, all the previous analyses had a suboptimal statistical power for assessing this question, with no more than 630 women in each study. Recently, investigators constructed a mathematical model of the dynamics of HIV-1 transmission in populations with or without the Δ32 mutation. This model predicted that the Δ32 allele would slow the heterosexual spread of the epidemic in populations where the mutation was common [13]. This prediction, coupled with the results from previous cohort studies, points out the importance of studying the role of the Δ32 deletion in HIV-1 transmission in a larger cohort of women. Studies have documented sex-specific differences in HIV-1 transmission, infection, and disease progression [10, 14–18]. Because the routes and mechanisms of HIV-1 infection may differ in significant ways between men and women, we investigated the relationship of CCR5 genotype to the likelihood of HIV-1 infection among women enrolled in the Women's Interagency HIV Study (WIHS), a large study of HIV-1 infection in women conducted in 5 US cities.

Objectives As the U.S. economy began its downward trend in 2008, many citizens lost their jobs and, ultimately, their employer-sponsored health care insurance. The expectation was that many of the newly uninsured would turn to emergency departments (EDs) for their health care. This study was undertaken to determine, first, if changes in the insurance status of the general population were reflected in the ED insurance payer mix and, second, whether there was evidence of an increased reliance on the ED as a continuing source of health care for any payer group(s). Methods This was a retrospective observational study using public data files from the National Hospital Ambulatory Medical Care Survey for Emergency Departments for years 2006 through 2010 (2008 ± 2 years). Changes in the relative proportions of ED visits funded annually by private insurance, Medicaid, Medicare, and self-pay (uninsured) were analyzed using a logistic model. Poisson regression was used to compare trends in the rates of ED visits for each payer type (i.e., number of ED visits per 100 persons with each insurance type). A linear spline term was used to determine if there was a change in each risk estimate after 2008 compared to the risk estimate before 2008. Results Before 2008, the odds of an ED visit being funded by private insurance increased by 4% per year (odds ratio [OR] = 1.04, 95% confidence interval [CI] = 0.98 to 1.10; p = 0.15), but after 2008 the odds reversed, decreasing by nearly 10% per year (OR = 0.91, 95% CI = 0.85 to 0.97; p = 0.02). Medicaid-funded visits demonstrated opposite trends with a small decreasing trend of 2% per year before 2008 (OR = 0.98, 95% CI = 0.92 to 1.04; p = 0.52), followed by a significantly increasing trend of 20% per year after 2008 (OR = 1.20, 95% CI = 1.12 to 1.27; p = 0.001). The growth in Medicaid-funded ED visits was attributable to increased numbers of visits by both pediatric (

Background Diastolic dysfunction is a highly prevalent cardiac abnormality in asymptomatic as well as ART ‐treated human immunodeficiency virus ( HIV ) patients. Although the mechanisms underlying depressed cardiac function remain obscure, diastolic dysfunction in SIV ‐infected rhesus macaques is highly correlated with myocardial viral load. As cardiomyocytes are not productively infected, damage may be an indirect process attributable to a combination of pro‐inflammatory mediators and viral proteins. Methods and Results Given the diverse roles of CCR5 in mediating recruitment of leukocytes to inflammatory sites and serving as a receptor for HIV entry into cells, we investigated the role of CCR5 in the SIV/macaque model of diastolic dysfunction. We found that in SIV‐infected macaques, CCR5 inhibition dramatically impacted myocardial viral load measured by qRT ‐PCR and prevented diastolic dysfunction measured by echocardiography. Complementary in vitro experiments using fluorescence microscopy showed that CCR5 ligands impaired contractile function of isolated cardiomyocytes, thus identifying CCR5 signaling as a novel mediator of impaired cardiac mechanical function. Conclusions Together, these findings incriminate SIV / HIV gp120‐ CCR 5 as well as chemokine‐ CCR 5 interactions in HIV ‐associated cardiac dysfunction. These findings also have important implications for the treatment of HIV ‐infected individuals: in addition to antiviral properties and reduced chemokine‐mediated recruitment and activation of inflammatory cells, CCR 5 inhibition may provide a cardioprotective benefit by preventing cardiomyocyte CCR 5 signaling.

Macrophage chemoattractant protein–1 (MCP-1) may be a key trigger for the influx of macrophages into the brain in human immunodeficiency virus (HIV) encephalitis. In this study, simian immunodeficiency virus–infected macaques that developed moderate-to-severe encephalitis had significantly higher MCP-1 levels in cerebrospinal fluid (CSF) than in plasma as early as 28 days after inoculation, which was before the development of brain lesions. In contrast, CSF:plasma MCP-1 ratios remained constant at preinoculation levels in macaques that developed minimal or no encephalitis. Abundant MCP-1 protein and mRNA were detected in both macrophages and astrocytes in the brain. Macaques with increased MCP-1 in CSF had significantly greater expression of markers of macrophage and microglia activation and infiltration (CD68; ) and astrocyte activation (glial fibrillary acidic protein; P p .003 and in white and gray matter, respectively). The results suggest that the P p .019 P p .031 CSF:plasma MCP-1 ratio may be a valuable prognostic marker for the development of HIVinduced central nervous system disease. About 25% of untreated human immunodeficiency virus (HIV)‐infected individuals and 15% of individuals treated with highly active antiretroviral therapy develop dementia, whereas a larger percentage develop HIV encephalitis [1‐4]. High virus load in the cerebrospinal fluid (CSF) identifies people with active HIV replication in the brain, but many of those individuals already have ongoing inflammatory changes in the brain or HIV-associated cognitive or motor deficits (or both) [5‐9]. Early identification of individuals with HIV encephalitis would permit the earlier use of antiretroviral drugs that cross the bloodbrain barrier. These drugs may be more effective in suppressing central nervous system (CNS) inflammation, thus reducing the risk of HIV-associated dementia. HIV encephalitis is characterized by activation of glial cells, including astrocytes and microglia, and infiltration of inflammatory cells, particularly macrophages, into the brain [10, 11].

We evaluated CD4 cell counts over a 3(1/2) year period following the initiation of potent antiretroviral therapy (ART) in the Multicenter AIDS Cohort Study. The study population included 314 HIV-infected gay men who provided CD4 cell counts for at least 2 years after the initiation of potent ART. Trends in CD4 cell counts and plasma HIV-RNA were analyzed by regression methods that incorporated the statistical dependencies of outcomes measured over time within individuals. Regardless of CD4 cell count at initiation of potent ART, CD4 cell counts increased significantly (p

Objectives: To determine the effectiveness of potent antiretroviral therapy in reducing opportunistic infections (OI) as both a presenting event and subsequent to an AIDS-defining event. Design and methods: A total of 543 seroconverters and 1470 men with AIDS were compared for the time to development of OI as the presenting AIDS event and as a subsequent event in the 1984-1989, 1990-1992, 1993-1995, and 1996-1998 periods, when the major treatments were no therapy, monotherapy, combination therapy, and potent antiretroviral therapy, respectively. Results: The seroconverters suffered 132 OI and the participants with AIDS had 717 OI. The relative hazard (RH) of OI as the presenting AIDS event declined by 81% in the calendar period when potent antiretroviral therapy was available compared with the monotherapy period. Declines were observed for Mycobacterium avium complex, cytomegalovirus disease, and esophageal candidiasis, but were statistically significant only for Pneumocystis carinii pneumonia. The RH of OI as a secondary infection dropped by 77% in the last calendar period compared with the monotherapy period. A significant decline was observed for all four OI. Prophylactic drug use did not increase in the era of potent antiretroviral therapy. Conclusion: The hazard of OI in the era of potent antiretroviral therapy has declined dramatically compared with the era of monotherapy, despite the concurrent decrease in the use of prophylactic drugs. Physicians should consider whether it is necessary to include prophylactic drugs as part of the complex drug regimen for patients on potent antiretroviral therapy.

Background Chemokines provide critical immune cell homing and activation signals that if altered could affect the inflammatory milieu and cellular composition of lymphoid tissues. During HIV-1 and simian immunodeficiency virus (SIV)-infection, the virus triggers an increase in inflammation or activation, leading to immunodeficiency and development of opportunistic infections, such as in the lungs-a massive interface between the host and the environment. Methods Chemokine, cytokine, and chemokine receptor expression profiles were determined using real-time reverse transcriptase-polymerase chain reaction and in situ hybridization in hilar lymph nodes (HiLNs) from cynomolgus macaques at different stages after infection with SIV/DeltaB670. Immunostaining of tissue sections and flow cytometric analysis of cryopreserved cells were used to examine cellular compositions of lymph nodes. Results Interferon-gamma, type 1 chemokine, and cognate chemokine receptor mRNAs were upregulated, whereas type 2 and homeostatic chemokine and chemokine receptor mRNAs were down-regulated in HiLNs after SIV infection. Local SIV and interferon-gamma levels were positively correlated with type 1 chemokine levels but negatively correlated with type 2 and homeostatic chemokine levels. Using in situ hybridization, Pneumocystis carinii rRNA was detected in lung-draining lymph nodes from animals with P. carinii pneumonia. Changes in the cellular composition of HiLNs included decreased proportions of CD4 cells and dendritic cells and increased proportions of CD8, CXCR3, and CCR5 cells. Conclusions SIV infection of cynomolgus macaques dramatically alters the cellular homing signals of lung-draining lymph nodes, which correlated with changes in the immune cellular composition. These changes could contribute to the loss of immune function that defines AIDS.

Background: Biomarkers of cartilage turnover and joint metabolism have a potential use in detecting early degenerative changes after a traumatic knee joint injury; however, no study has analyzed biomarkers before an anterior cruciate ligament (ACL) injury and again after injury or in comparison with a similar group of uninjured controls. Hypothesis: Changes in serum biomarker levels and the ratio of cartilage degradation to synthesis, from baseline to follow-up, would be significantly different between ACL-injured patients and uninjured controls. Study Design: Case-control study; Level of evidence, 3. Methods: This case-control study was conducted to examine changes in serum biomarkers of cartilage turnover following ACL injury in a young athletic population. Specifically, 2 markers for type II collagen and aggrecan synthesis (CPII and CS846, respectively) and 2 markers of types I and II degradation and type II degradation only (C1,2C and C2C, respectively) were studied. Preinjury baseline serum samples and postinjury follow-up samples were obtained for 45 ACL-injured cases and 45 uninjured controls matched for sex, age, height, and weight. Results: Results revealed significant decreases in C1,2C ( P = .042) and C2C ( P = .006) over time in the ACL-injured group when compared with the controls. The change in serum concentrations of CS846 from baseline to follow-up was also significantly different between the ACL-injured patients and uninjured controls ( P = .002), as was the change between groups in the ratio of C2C:CPII over time ( P = .013). No preinjury differences in the ratio of C1,2C:CPII or C2C:CPII were observed between groups; however, postinjury differences were observed for both ratios. Conclusion: Changes in biomarker concentrations after an ACL injury suggest an alteration in cartilage turnover and joint metabolism in those sustaining ACL injuries compared with uninjured matched controls.

Fusion inhibitors are a class of antiretroviral drugs used to prevent entry of HIV into host cells. Many of the fusion inhibitors being developed, including the drug enfuvirtide, are peptides designed to competitively inhibit the viral fusion protein gp41. With the emergence of drug resistance, there is an increased need for effective and unique alternatives within this class of antivirals. One such alternative is a class of cyclic, cationic, antimicrobial peptides known as θ-defensins, which are produced by many non-human primates and exhibit broad-spectrum antiviral and antibacterial activity. Currently, the θ-defensin analog RC-101 is being developed as a microbicide due to its specific antiviral activity, lack of toxicity to cells and tissues, and safety in animals. Understanding potential RC-101 resistance, and how resistance to other fusion inhibitors affects RC-101 susceptibility, is critical for future development. In previous studies, we identified a mutant, R5-tropic virus that had evolved partial resistance to RC-101 during in vitro selection. Here, we report that a secondary mutation in gp41 was found to restore replicative fitness, membrane fusion, and the rate of viral entry, which were compromised by an initial mutation providing partial RC-101 resistance. Interestingly, we show that RC-101 is effective against two enfuvirtide-resistant mutants, demonstrating the clinical importance of RC-101 as a unique fusion inhibitor. These findings both expand our understanding of HIV drug-resistance to diverse peptide fusion inhibitors and emphasize the significance of compensatory gp41 mutations.

The authors evaluated the association of a virologic response to highly active antiretroviral therapy, or a subsequent rebound, with performance on two measures of psychomotor speed in HIV-positive subjects. Virologic suppression was associated with improved performance on measures of psychomotor speed, and virologic rebound was associated with psychomotor speed performance decline. Changes in plasma HIV viral load in HIV-positive individuals with cognitive slowing correlate with performance on tests of psychomotor speed.

Non-complaint Egyptian homes were examined to determine the residential culturable airborne bacterial concentrations so that these could be used as comparisons in indoor air quality investigations. Concentrations of airborne bacteria were investigated in 26 urban flats across Cairo and 17 rural flats in the Dakahlia governorate. Air samples were collected using a two-stage viable cascade impactor sampler, dividing particles into coarse (8 μm) and fine (8 μm) sizes. For urban flats, the year's median indoor and comparison site concentrations were 9133 CFU/m(3) and 9423 CFU/m(3), respectively. For rural flats, the year's median indoor and comparison site concentrations were 15,915 CFU/m(3) and 10,859 CFU/m(3), respectively. The median indoor bacterial concentrations increased in winter and spring compared to autumn and summer. Winter months had the greatest median concentration for coarse indoor organisms, whereas spring had the largest for the fine indoor organisms. Fine bacterial concentration composed more than 60% of the indoor bacterial fraction.

Embryology is integrated into the Clinically Oriented Anatomy course at the Texas Tech University Health Sciences Center School of Medicine. Before 2008, the same instructor presented embryology in 13 face-to-face lectures distributed by organ systems throughout the course. For the 2008 and 2009 offerings of the course, a hybrid embryology instruction model with four face-to-face classes that supplemented online recorded lectures was used. One instructor delivered the lectures face-to-face in 2007 and by online videos in 2008-2009, while a second instructor provided the supplemental face-to-face classes in 2008-2009. The same embryology learning objectives and selected examination questions were used for each of the three years. This allowed direct comparison of learning outcomes, as measured by examination performance, for students receiving only face-to-face embryology instruction versus the hybrid approach. Comparison of the face-to-face lectures to the hybrid approach showed no difference in overall class performance on embryology questions that were used all three years. Moreover, there was no differential effect of the delivery method on the examination scores for bottom quartile students. Students completed an end-of-course survey to assess their opinions. They rated the two forms of delivery similarly on a six-point Likert scale and reported that face-to-face lectures have the advantage of allowing them to interact with the instructor, whereas online lectures could be paused, replayed, and viewed at any time. These experiences suggest the need for well-designed prospective studies to determine whether online lectures can be used to enhance the efficacy of embryology instruction.

Vaginal microbicides represent a promising approach for preventing heterosexual HIV transmission. However, preclinical evaluation should be conducted to ensure that microbicides will be safe for human cells and healthy microflora of the female reproductive tract. One microbicide candidate, RC-101, has been effective and well tolerated in preliminary cell culture and macaque models. However, the effect of RC-101 on primary vaginal tissues and resident vaginal microflora requires further evaluation.We treated primary vaginal tissues and vaginal bacteria, both pathogenic and commensal, with RC-101 to investigate effects of this microbicide.RC-101 was well tolerated by host tissues, and also by commensal vaginal bacteria. Simultaneously, pathogenic vaginal bacteria, which are known to increase susceptibility to HIV acquisition, were inhibited by RC-101.By establishing vaginal microflora, the specific antibacterial activity of RC-101 may provide a dual mechanism of HIV protection. These findings support advancement of RC-101 to clinical trials.

An urgent need exists for HIV-1 microbicides. Here, we describe the in vivo testing of lactic acid bacteria bioengineered to secrete cyanovirin-N. We fed pigtail macaques a yogurt formulation that used bioengineered strains as a starter culture. Cyanovirin-N expression could be detected in the rectal vault during and immediately after feeding. Ex vivo viral challenge of rectal tissue biopsies revealed that peak viral burden was significantly lower in tissue obtained from experimental animals compared to control animals. Formulation of candidate compounds in lactic acid bacteria and their oral administration appears to be a feasible strategy for mucosal delivery of microbicides.

One major activity of chemokines is the recruitment of immune cells to sites of infection and inflammation. CD4+ Th1 cells play critical roles in host defense against pathogens and in the pathogenesis of many immune-mediated diseases. It was reported that epigallocatechin-3-gallate (EGCG) exhibits anti-inflammatory properties, but the mechanisms have not been completely defined. In this study, we found that EGCG markedly decreased recruitment of murine OVA-specific Th1 cells and other inflammatory cells into the airways in a Th1 adoptive-transfer mouse model. In vitro analysis revealed that EGCG inhibited CXCR3 ligand-driven chemotaxis of murine and human cells. Surface plasmon resonance studies revealed that EGCG bound directly to chemokines CXCL9, CXCL10, and CXCL11. These results indicated that one anti-inflammatory mechanism of EGCG is binding of proinflammatory chemokines and limiting their biological activities. These findings support further development of EGCG as a potent therapeutic for inflammatory diseases.

Author(s): Cole, Alexander M; Patton, Dorothy L; Rohan, Lisa C; Cole, Amy L; Cosgrove-Sweeney, Yvonne; Rogers, Nicole A; Ratner, Deena; Sassi, Alexandra B; Lackman-Smith, Carol; Tarwater, Patrick; Ramratnam, Bharat; Ruchala, Piotr; Lehrer, Robert I; Waring, Alan J; Gupta, Phalguni | Abstract: BackgroundRC-101 is a congener of the antiretroviral peptide retrocyclin, which we and others have reported is active against clinical HIV-1 isolates from all major clades, does not hemagglutinate, and is non-toxic and non-inflammatory in cervicovaginal cell culture. Herein, film-formulated RC-101 was assessed for its antiviral activity in vitro, safety in vivo, retention in the cervix and vagina, and ability to remain active against HIV-1 and SHIV after intravaginal application in macaques.Methodology/principal findingsRC-101 was formulated as a quick-dissolving film (2000 µg/film), retained complete activity in vitro as compared to unformulated peptide, and was applied intravaginally in six pigtailed macaques daily for four days. At one and four days following the final application, the presence of RC-101 was assessed in peripheral blood, cervicovaginal lavage, cytobrushed cervicovaginal cells, and biopsied cervical and vaginal tissues by quantitative western blots. One day following the last film application, cervical biopsies from RC-101-exposed and placebo-controlled macaques were collected and were subjected to challenge with RT-SHIV in an ex vivo organ culture model. RC-101 peptide was detected primarily in the cytobrush and biopsied cervical and vaginal tissues, with little to no peptide detected in lavage samples, suggesting that the peptide was associated with the cervicovaginal epithelia. RC-101 remained in the tissues and cytobrush samples up to four days post-application, yet was not detected in any sera or plasma samples. RC-101, extracted from cytobrushes obtained one day post-application, remained active against HIV-1 BaL. Importantly, cervical biopsies from RC-101-treated animals reduced RT-SHIV replication in ex vivo organ culture as compared to placebo-treated animals.Conclusions/significanceFormulated RC-101 was stable in vivo and was retained in the mucosa. The presence of antivirally active RC-101 after five days in vivo suggests that RC-101 would be an important molecule to develop further as a topical microbicide to prevent HIV-1 transmission.

Purpose: Decreases in α myosin heavy chain (α-MHC) is a common feature of human heart failure (HF), whereas α-MHC overexpression in transgenic (TG) rabbits is cardioprotective against tachycardia-induced cardiomyopathy (TIC). Hypothesizing that MHC isoform content alterations would impact sarcomere and mitochondrial energetics protein complement, we investigated the impact of α-MHC overexpression on global cardiac protein expression. Experimental design: Protein expression was assessed by two-dimensional gel electrophoresis and MS on the extracts from TG and nontransgenic (NTG) rabbits under TIC or sham-operated conditions. Results: We observed significant changes in the levels of actin, myosin light chain 2, and desmin between the left ventricular (LV) tissue of TG and NTG animals. The proteome was broadly impacted, with significant changes in mitochondrial energetics and chaperone protein families. No changes were observed in total cellular MHC or in myofibril-associated MHC. In myofibrils isolated from TGsham animals, only actin levels were altered in TGsham compared with NTGsham animals, suggesting careful myofibril assembly regulation. Conclusions and clinical Relevance: These data suggest that myofibril protein composition may protect against TIC, emphasizing protein interconnectivity and demonstrating the need for broad-based proteomic studies in understanding targeted genetic manipulations. This study identifies the targets for future development of cardioprotective agents and elucidates tachycardia-induced heart failure pathways.

The molecular mechanisms underlying learning and memory impairment in patients with HIV-associated neurological disease have remained unclear. Calcium/calmodulin-dependent kinase II (CaMKII) has key roles in synaptic potentiation and memory storage in neurons and also may have immunomodulatory functions. To determine whether HIV and simian immunodeficiency virus (SIV) induce alterations in CaMKII expression and/or activation (autophosphorylation) in the brain, we measured CaMKII alterations by quantitative immunoblotting in both an in vitro HIV/neuronal culture model and in vivo in an SIV-infected macaque model of HIV-associated neurological damage. Using primary rat hippocampal neuronal cultures treated with culture supernatants harvested from HIV-1–infected human monocyte-derived macrophages (HIV/MDM), we found that CaMKII activation declined after exposure of neurons to HIV/MDM. Consistent with our in vitro measurements, a significant decrease in CaMKII activation was present in both the hippocampus and frontal cortex of SIV-infected macaques compared with uninfected animals. In SIV-infected animals, total CaMKII expression in the hippocampus correlated well with levels of synaptophysin. Furthermore, CaMKII expression in both the hippocampus and frontal cortex was inversely correlated with viral load in the brain. These findings suggest that alterations in CaMKII may compromise synaptic function in the early phases of chronic neurodegenerative processes induced by HIV.

Central nervous system (CNS) invasion during acute-stage HIV-infection has been demonstrated in a small number of individuals, but there is no evidence of neurological impairment at this stage and virus infection in brain appears to be controlled until late-stage disease. Using our reproducible SIV macaque model to examine the earliest stages of infection in the CNS, we identified immune responses that differentially regulate inflammation and virus replication in the brain compared to the peripheral blood and lymphoid tissues. SIV replication in brain macrophages and in brain of SIV-infected macaques was detected at 4 days post-inoculation (p.i.). This was accompanied by upregulation of innate immune responses, including IFNbeta, IFNbeta-induced gene MxA mRNA, and TNFalpha. Additionally, IL-10, the chemokine CCL2, and activation markers in macrophages, endothelial cells, and astrocytes were all increased in the brain at four days p.i. We observed synchronous control of virus replication, cytokine mRNA levels and inflammatory markers (MHC Class II, CD68 and GFAP) by 14 days p.i.; however, control failure was followed by development of CNS lesions in the brain. SIV infection was accompanied by induction of the dominant-negative isoform of C/EBPbeta, which regulates SIV, CCL2, and IL6 transcription, as well as inflammatory responses in macrophages and astrocytes. This synchronous response in the CNS is in part due to the effect of the C/EBPbeta on virus replication and cytokine expression in macrophage-lineage cells in contrast to CD4+ lymphocytes in peripheral blood and lymphoid tissues. Thus, we have identified a crucial period in the brain when virus replication and inflammation are controlled. As in HIV-infected individuals, though, this control is not sustained in the brain. Our results suggest that intervention with antiretroviral drugs or anti-inflammatory therapeutics with CNS penetration would sustain early control. These studies further suggest that interventions should target HIV-infected individuals with increased CCL2 levels or HIV RNA in the CNS.

A rise in foodborne outbreaks in the United States associated with fresh produce has resulted in increased concerns with the importation of fruits and vegetables. Mexico is a major exporter of produce to the United States, particularly tomatoes and bell peppers. A quantitative microbial risk assessment (QMRA) was conducted to evaluate the public health impact of protozoan-laden water irrigating produce in Culiacan, Sinaloa, Mexico. Specifically, a QMRA was conducted to address the human health impact associated with consumption of tomatoes, bell peppers, cucumbers, and lettuce irrigated with water contaminated with Cryptosporidium and Giardia. Yearly infection risks were estimated and assumed a 120-day exposure in a given year. Annual risks range from 9 x 10(-6) for Cryptosporidium at the lowest concentration associated with bell peppers to almost 2 x 10(-1) for exposure to Giardia on lettuce at the highest detected concentration. With the relatively high number of illnesses resulting from produce-related outbreaks, addressing pre- and postharvest points of contamination for fruits and vegetables consumed raw should be a food industry priority. This research shows how QMRA can be used to interpret microbial contamination data for public health significance and subsequently provide the foundation for guideline development.

Staphylococcus aureus, a major source of nosocomial and community-acquired infections, has a nasal carriage rate exceeding 25% in the human population. To elucidate host-pathogen interactions pertaining to nasal carriage, we examined the role of interleukin-1 (IL-1) in the colonization of human nasal epithelial cells (NEC) by a nasal carrier strain and a non-carrier strain of S. aureus. Using an organotypic model of the nasal epithelium, we observed that inoculation with a non-carrier strain of S. aureus induced production of IL-1 from NEC, but the expression of this cytokine was significantly reduced when NEC were inoculated with a carrier strain. Moreover, both IL-1alpha and IL-1beta significantly decreased the growth of the nasal carrier strain of S. aureus (P < 0.001, n = 17 to n = 25); however the growth of the non-carrier strain was unaffected. Interestingly, it was found that several nasal carrier strains of S. aureus form quorum-dependent biofilms, which can be partially inhibited when preincubated with IL-1alpha. Taken together these data suggest that, although nasal carrier strains of S. aureus are sensitive to IL-1, they display a significant colonization advantage by both preventing the host from expressing IL-1 and elaborating a protective biofilm.

This study compares population mean hearing threshold levels in decibels (dB) at 4 kHz among the 2001–02 National Health and Nutrition Examination Survey (NHANES) (n = 1,872) and the 2003–05 Fort Bliss Army Active Duty (AD) (n = 9,096), National Guard (NG) (n = 3,842), and Reserve Components (RC) (n = 2,025) and by gender. Comparisons between male populations show that mean hearing thresholds are not significantly different (p < 0.05) between U.S. Army Active Duty males and NHANES males, which differ from a 1984 U.S. Army Active Duty/1971–74 NHANES study showing significantly higher hearing thresholds for the Army Active Duty population. In addition, this study shows that Active Duty males have significantly lower hearing thresholds than National Guard males at ages

Plasma viral load has been shown to be a meaningful prognostic marker for disease progression in untreated, HIV-1 subtype B-infected subjects in United States and Western Europe and therefore used as a prognostic marker for disease progression. Because of high expenses of commercially available viral load assays, the role of viral load in disease progression has not been evaluated in HIV-1 subtype C-infected patients in India.We developed an inexpensive real-time reverse transcriptase-polymerase chain reaction assay to quantify viral load in plasma of HIV-1 subtype C-infected subjects from India and used it in a longitudinal analysis of viral load and CD4 cell number in HIV-infected subjects from Calcutta, India.The real-time reverse transcriptase-polymerase chain reaction assay can quantify plasma viral load with a linear range of detection from 10 to 10 HIV-1 RNA copies per input. Longitudinal analysis of viral load in a cohort of 39 subjects over an average period of approximately 3 years indicates that 1-log increase in HIV-1 RNA level was associated with a decline of 67 CD4 cell count. Furthermore, HIV-1 RNA level between 500 and 50,000 copies per milliliter would predict a 12.9% decrease in CD4 cell count per year, whereas HIV-1 RNA levels above 50,000 copies HIV-1 RNA per milliliter would predict a 25.3% decrease in CD4 cells per year. In addition, we estimated that the mean incubation period of disease development, as defined by the loss of CD4 below 200, is 8.2 years.Our report on the level of viral load on predicting CD4 decline in Indian subjects with HIV-1 provides an additional important tool to the physicians for treating and planning a therapeutic strategy to control HIV-1 infection in India.

HIV-1 subtype C has been the predominant subtype throughout the course of the HIV-1 epidemic in India regardless of the geographic region of the country. In an effort to understand the mechanism of subtype C predominance in this country, we have investigated the in vitro replication fitness and transmission efficiency of HIV-1 subtypes A and C from India. Using a dual infection growth competition assay, we found that primary HIV-1 subtype C isolates had higher overall relative fitness in PBMC than subtype A primary isolates. Moreover, in an ex vivo cervical tissue derived organ culture, subtype C isolates displayed higher transmission efficiency across cervical mucosa than subtype A isolates. We found that higher fitness of subtype C was not due to a trans effect exerted by subtype C infected PBMC. A half genome A/C recombinant clone in which the 3′ half of the viral genome of subtype A was replaced with the corresponding subtype C3′ half, had similar replicative fitness as the parental subtype A. These results suggest that the higher replication fitness and transmission efficiency of subtype C virus compared to subtype A virus from India is most probably not due to the envelope gene alone and may be due to genes present within the 5′ half of the viral genome or to a more complex interaction between the genes located within the two halves of the viral genome. These data provide a model to explain the asymmetric distribution of subtype C over other subtypes in India.

The authors conducted a study in the El Paso, Texas, region to assess the seasonal bioaerosol concentrations in a convenience sample of one-story residences. The authors sampled the same houses for each season over the course of a year (March 2005 to February 2006) to determine bacterial and fungal concentrations. They used a two-stage ambient culturable sampler system to collect the bioaerosol samples. They took indoor and outdoor bioaerosol samples and studied meteorological conditions for each house at each season. The study found that most of the measured bioaerosol concentrations differed statistically by season (p.05). The greatest concentrations throughout the year were found to occur in fine-sized indoor bacteria during the winter. Meteorological conditions were found not to significantly influence bioaerosol concentrations throughout the year.

Human immunodeficiency virus (HIV) infection frequently causes neurologic disease even with anti-retroviral treatment. Although associations between MHC class I alleles and acquired immunodeficiency syndrome (AIDS) have been reported, the role MHC class I alleles play in restricting development of HIV-induced organ-specific diseases, including neurologic disease, has not been characterized. This study examined the relationship between expression of the MHC class I allele Mane-A*10 and development of lentiviral-induced central nervous system (CNS) disease using a well-characterized simian immunodeficiency (SIV)/pigtailed macaque model. The risk of developing CNS disease (SIV encephalitis) was 2.5 times higher for animals that did not express the MHC class I allele Mane-A*10 (P = 0.002; RR = 2.5). Animals expressing the Mane-A*10 allele had significantly lower amounts of activated macrophages, SIV RNA, and neuronal dysfunction in the CNS than Mane-A*10 negative animals (P

Summary: Lymphoid tissues are sites of soluble and cell-associated antigen sampling of peripheral tissues, and they are key compartments for the generation of cellular and humoral immune responses. Hilar lymph nodes (HiLNs), which drain the lungs, were examined to understand the effects of simian immunodeficiency virus (SIV) infection on this compartment of the immune system. Histologic and messenger RNA (mRNA) expression profiling approaches were used to determine the numbers, types, and distributions of SIV viral RNA + cells and to identify differentially expressed genes in HiLNs during SIVinfection. SIV RNA + cells were found to be primarily CD68 2 and localized to paracortical and medullary regions early in infection, whereas they resided mainly in paracortex during AIDS. As SIV infection progressed, CXCL9, CXCL10, interferon-g, and Toll-like receptor 3 levels all increased. In contrast, CCL19 increased early in infection but decreased during AIDS, whereas CCL21 decreased progressively throughout infection. Finally, local levels of cellular activation were increased throughout infection. Taken together, these findings indicate that SIV infection leads to an inflammatory environment in lung-draining lymph nodes that is characterized by type 1 cytokines and chemokines and likely has an impact on the nature and strength of immune responses to pulmonary pathogens.

The identification of biomarkers identifying onset of human immunodeficiency virus-associated dementia (HIV-D) is critical for diagnosis and the elucidation of pathophysiologic pathways.To examine the association between platelet decline from baseline and HIV-D.Prospective cohort study within the North-East AIDS Dementia cohort.Four participating referral centers in the United States.A total of 396 subjects with advanced human immunodeficiency virus (HIV) infection recruited between 1998 and 2003 and undergoing serial neurologic assessments. Eligibility criteria required CD4 cell counts less than 200/microL or less than 300/microL with evidence of cognitive impairment. A cohort subset without prevalent HIV-D at baseline and without incident HIV-D at the visit immediately after baseline was analyzed (n = 146). Main Outcome Measure Time to first diagnosis of HIV-D.After a median follow-up of 31.1 months, 40 subjects developed HIV-D. Platelet decline from baseline was associated with the development of HIV-D when examined as a time-dependent variable lagged by 6 to 12 months before outcome (multivariate hazard ratio [HR], 2.39; 95% confidence interval [CI], 1.14-5.02; P = .02). This association was stronger during the first 2 years of follow-up (multivariate HR, 6.76; 95% CI, 2.36-19.41; P.001) than during later years (multivariate HR, 0.94; 95% CI, 0.33-2.67; P = .90).These results suggest that individuals with declining platelet counts are at greater risk for HIV-D and that the dynamics of circulating platelets vary with respect to the temporal progression of HIV-D. This highlights an avenue to be explored in the understanding of HIV-D pathogenesis.

The Hearing Conservation Service at Fort Bliss conducted baseline-hearing assessments from January 2003 to March 2005 on 14,974 soldiers in the Active Duty (AD), National Guard (NG), and Reserve Component (RC). The percentages of soldiers withH-2 (i.e., nondeployable) hearing profiles based on Army component and gender are as follows: AD male = 2.21%; AD female = 0.65%; NG male = 5.05%; NG female = 1.64%; RC male = 5.02%; and RC female = 0.54%. Female soldiers in all three components and AD male soldiers are not significantly different (p0.05) from each other and have a significantly lower percentage ofH-2 hearing profiles than NG and RC male soldiers after adjusting for age. With the Army engaged in worldwide missions, these results should prove useful to commanders and medical officers for assessing deployment capabilities and for hearing conservation interventions.

As the prevalence of human immunodeficiency virus (HIV)-induced central nervous system (CNS) disease has increased with antiretroviral treatment, there is a critical need for identifying biomarkers that predict HIV CNS disease. To identify novel hematologic markers that precede and predict CNS disease, the authors examined longitudinal hematology data from 47 simian immunodeficiency virus (SIV)-infected macaques. This study demonstrated that the magnitude of decline in circulating platelet counts beginning at day 28 post infection, during asymptomatic SIV infection, predicted the eventual development of SIV encephalitis. Univariate analysis performed on platelet values obtained day 56 post inoculation demonstrated that SIV-infected macaques with the greatest decline in platelet numbers were 18 times more likely to develop SIV CNS disease than SIV-infected animals with minimal to no decline in circulating platelet counts. Decline in platelet number was a more robust marker than decline in hemoglobin levels, a previously identified marker of HIV CNS disease. The identification of an association between decline in platelets and the development of encephalitis demonstrates that monitoring platelet decline in HIV-infected individuals may serve as a predictive marker for clinical progression to HIV-induced CNS disease. Identifying those HIV-infected individuals at risk for CNS disease during asymptomatic stages of infection would promote early interventive, neuroprotective therapy to prevent neuronal damage and loss.

The objective of this study was to evaluate the levels of bacteria in the air plume immediately upwind at 25 m and downwind at locations 25 m, 50 m, 100 m, and 150 m from a confined animal feeding operation (CAFO). It was hypothesized that this would give insight into determining the maximal distance that bacterial organisms release from a CAFO could travel, which would be important in determining the optimal siting distance for future CAFO in relation to high population areas. The Andersen two-stage sampler was used to collect all of the bacterial samples from the animal confinement facilities. The data show a marked increase in bacterial CFUs/m3 inside the facility (18,132 CFU/m3 average) versus upwind (63 CFU/m3 average) and a steady downwind decrease out to approximately 150 m. Staphylococcus aureus was found to account for 76% of the organisms recovered. We conclude that the optimal placement of a swine CAFO would be at least 200 m from a residential area.

BACKGROUND: The brain is considered to be a reservoir of latent human immunodeficiency virus (HIV) and simian immunodeficiency virus (SIV). We examined the mechanism by which innate immune responses contribute to the establishment of this reservoir. METHODS: Gene-specific RNA and DNA were quantitated using real-time reverse-transcription polymerase chain reaction (RT-PCR). Protein expression was examined using Western blot analysis. Binding to and regulation of the SIV long terminal repeat (LTR) was examined using electrophoretic mobility shift assay, luciferase reporter constructs, and chromatin immunoprecipitation assay. RESULTS: Interferon-beta (IFN-beta) and myxovirus A (MxA) mRNA are produced in the brain during acute SIV infection. IFN-beta both suppresses SIV LTR activity and induces expression of the dominant-negative isoform of CCAAT/enhancer-binding protein-beta (C/EBP-beta). C/EBP-beta and its dominant-negative isoform respectively enhance and suppress histone acetylation at the SIV LTR and are present at the SIV LTR in vivo. SIV DNA persists when viral RNA is undetectable in the brain, and activation of the LTR is suppressed at the level of histone acetylation. CONCLUSION: Innate immune responses to virus infection that suppress acute virus replication in the brain also facilitate transcriptional latency of SIV. These data provide the first mechanistic model of HIV latency in the brain.

There is currently no SIV macaque model in which the effects of combination antiretroviral therapy on tissue immune responses and latent reservoirs have been measured. This study was performed to define the impact of combination therapy on the specificity and distribution of the T lymphocyte response in multiple tissue compartments. Pigtailed macaques (Macaca nemestrina) were infected with SIV/17E-Fr and treated with combination antiretroviral therapy consisting of 9-R-(2-phosphonomethoxypropyl)adenine (PMPA) and beta-2',3'-dideoxy-3'-thia-5-fluorocytidine (FTC). The SIV-specific T lymphocyte response was measured in peripheral blood, spleen and several lymph nodes at necropsy by IFN-gamma Elispot analysis. Two animals (one treated, one untreated) had high acute peak viremia, which was associated with lower SIV-specific T lymphocyte responses in the peripheral blood and lymphoid tissues. In the treated animal, viremia was controlled to low or undetectable for the study duration, and virus-specific responses remained low. The untreated animal remained viremic throughout the study and developed clinical symptoms of AIDS. In contrast, the two animals that had lower acute peak viremia (one treated, one untreated) had more robust T lymphocyte responses, and controlled viral replication. Virus-specific responses were detected in the treated animal despite 6 months of suppressive therapy. These data suggest that in this model, in the context of acute peak viremia and weak T cell responses, combination therapy may be essential to control virus replication and disease progression. Conversely, in the setting of low initial viremia and robust T lymphocyte responses, treatment does not have a detrimental effect on the immune response.

The lentiviral Gag polyprotein (Pr55 Gag ) is cleaved by the viral protease during the late stages of the virus life cycle. Proteolytic cleavage of Pr55 Gag is necessary for virion maturation, a structural rearrangement required for infectivity that occurs in budded virions. In this study, we investigate the relationship between phosphorylation of capsid (CA) domains in Pr55 Gag and its cleavage intermediates and their cleavage by the viral protease in simian immunodeficiency virus (SIV). First, we demonstrate that phosphorylated forms of Pr55 Gag , several CA-containing cleavage intermediates of Pr55 Gag , and the free CA protein are detectable in SIV virions but not in virus-producing cells, indicating that phosphorylation of these CA-containing Gag proteins may require an environment that is unique to the virion. Second, we show that the CA domain of Pr55 Gag can be phosphorylated in budded virus and that this phosphorylation does not require the presence of an active viral protease. Further, we provide evidence that CA domains (i.e., incompletely cleaved CA) are phosphorylated to a greater extent than free (completely cleaved) CA and that CA-containing Gag proteins can be cleaved by the viral protease in SIV virions. Finally, we demonstrate that Pr55 Gag and several of its intermediates, but not free CA, are actively phosphorylated in budded virus. Taken together, these data indicate that, in SIV virions, phosphorylation of CA domains in Pr55 Gag and several of its cleavage intermediates likely precedes the cleavage of these domains by the viral protease.

The study objective was to compare the prognostic value of plasma HIV RNA and CD4 cell count at baseline and as time-updated variables in highly active antiretroviral therapy (HAART) users for two outcomes: development of AIDS and change in CD4 cell count.The study population comprised 387 men enrolled in the Multicenter AIDS Cohort Study who were AIDS-free and initiated HAART between 1996 and 2001. Follow-up until AIDS diagnosis (n=36, 9%) or the last AIDS-free visit was included. To determine the predictive value of combining HIV RNA and CD4 cell count, regression tree methods using recursive partitioning at pre-specified cut points for both variables were used.Low CD4 cell count was a strong predictor of AIDS among HAART users. However, HIV RNA showed strong prognostic value for AIDS development among those with CD4 cell counts250 x 10(6) cells/l, in whom an HIV RNA level1000 copies/ml carried a 4.6-fold greater risk of developing AIDS. HIV RNA5000 copies/ml was also predictive of subsequent increase in CD4 cell count with significantly higher increases among those with initial CD4 counts300 x 10(6) cells/l.Although, in HAART users, CD4 cell count was the primordial prognostic marker, an HIV RNA1000 copies/ml attained after HAART initiation was a strong predictor of the rate of subsequent CD4 cell count increase and of developing AIDS in patients whose CD4 cell counts were250 x 10(6) cells/l.

Both antiretroviral therapy and the human coreceptor polymorphism CCR2-V64I slow progression of human immunodeficiency virus type 1 (HIV-1) disease. To examine the effect of V64I on disease progression in patients receiving therapy, we determined CCR2 genotypes in the Women's Interagency HIV Study cohort. We studied 2047 HIV-1-infected women, most of whom initiated treatment during the study. No association was seen between CCR2 genotype and either disease progression or therapeutic response, suggesting that the benefits of treatment most likely overshadow the salutary effects of the V64I polymorphism.

Central nervous system (CNS) disease is a frequent complication of human immunodeficiency virus (HIV)-1 infection. Identification of cellular mechanisms that control virus replication and that mediate development of HIV-associated neuropathology will provide novel strategies for therapeutic intervention. The milieu of the CNS during HIV infection is extraordinarily complex because of infiltration of inflammatory cells and production of chemokines, cytokines, and neurotoxic molecules. Cells in the CNS must integrate signaling pathways activated simultaneously by products of virus replication and infiltrating immune cells. In this study, we examined activation of mitogen-activated protein kinases (MAPKs) in the CNS of simian immunodeficiency virus-infected macaques during acute, asymptomatic, and terminal infection. We demonstrate that significantly increased (P < 0.02) activation of ERK MAPK, typically associated with anti-apoptotic and neuroprotective pathways, occurs predominantly in astrocytes and immediately precedes suppression of virus replication and macrophage activation that occur after acute infection. In contrast, significantly increased activation of proapoptotic, neurodegenerative MAPKs JNK (P = 0.03; predominantly in macrophages/microglia), and p38 (P = 0.03; predominantly in neurons and astrocytes) after acute infection correlates with subsequent resurgent virus replication and development of neurological lesions. This shift from classically neuroprotective to neurodegenerative MAPK pathways suggests that agents that inhibit activation of JNK/p38 may be protective against HIV-associated CNS disease.

Duration of treatment interruption (TI) was investigated in 105 human immunodeficiency virus—infected patients whose antiretroviral therapy was interrupted with the intention to resume therapy on the basis of clinical or laboratory indicators. In a mixed cohort study, 57% of patients had not resumed therapy at the time of writing (median TI duration, 114 weeks); the most recent analysis of this group revealed a mean CD4 cell count of 500 cells/mm 3 . Patients with lower CD4 cell counts at therapy initiation were more likely to resume therapy than were those with counts of >500 cells/mm 3 (

To determine the association between sexual exposure and hepatitis C virus (HCV) infection in urban Chennai, India, a random sample of adults who live in a slum community completed interviews and provided samples to test for HCV, herpes simplex virus type 2 (HSV-2), and other sexually transmitted infections (STIs). All analyses excluded recent and current injection drug users. HCV infection was not associated with the reported number of sex partners for men or women. Women were more likely to be HCV infected if they reported previous genital ulcer disease (adjusted odds ratio [AOR], 3.88; 95% confidence interval [95% CI], 0.94-16.0; marginally statistically significant). Men were more likely to be HCV infected if they were HSV-2 infected (AOR, 3.85; 95% CI, 1.18-12.6) or reported having had sex with men (AOR, 3.61; 95% CI, 1.00-13.1). Sexual transmission of HCV infection may be facilitated by ulcerative STIs and male-male sexual practices, but it appears to occur infrequently in this population.

An accelerated, consistent macaque simian immunodeficiency virus (SIV) model in which over 90% of pigtailed macaques ( Macaca nemestrina ) coinoculated with SIV/17E-Fr and SIV/DeltaB670 developed encephalitis was used to determine whether central nervous system (CNS) lesions are associated with the replication of specific genotypes in the brain and, more specifically, in the microglia. Ten of 11 inoculated macaques had severe ( n = 3), moderate ( n = 5), or mild ( n = 2) encephalitis at 3 months postinoculation. To compare actively replicating viral genotypes in the CNS and in microglia with those in the periphery, the V1 region of the SIV envelope gene was amplified and sequenced from RNA extracted from basal ganglia, from microglial cells isolated from the brain, and from peripheral blood mononuclear cells (PBMC) isolated from blood at the time of death. To distinguish between actively replicating with latent viral genotypes in the CNS, viral genotypes in RNA and DNA from basal ganglia were compared. Two macrophage-tropic, neurovirulent viruses, SIV/17E-Fr and SIV/DeltaB670 Cl-2, predominated in the brain RNA of macaques with encephalitis, comprising 95% of the genotypes detected. The same two viral genotypes were present at the same frequencies in microglial cell RNA, suggesting that microglia are pivotal in the selective replication of neurovirulent viruses. There was a significantly greater number of viral genotypes in DNA than there were in RNA in the brain ( P = 0.004), including those of both the macrophage- and lymphocyte-tropic viral strains. Furthermore, significantly fewer viral genotypes were detected in brain RNA than in PBMC RNA at the time of death ( P = 0.004) and the viral strain that predominated in the brain frequently was different from that which predominated in the PBMC of the same animal. These data suggest that many viral genotypes enter the brain, but only a limited subset of macrophage-tropic, neurovirulent viruses replicate terminally in the brains of macaques with encephalitis. They further suggest that the selection of macrophage-tropic, neurovirulent viruses occurs not at the level of the blood-brain barrier but at a stage after virus entry and that microglial cells may play an important role in that selection process.

Latent reservoirs of human immunodeficiency virus (HIV) present significant challenges for eradicating HIV from infected persons, particularly reservoirs in the brain established during acute infection. A simian immunodeficiency virus (SIV)/macaque model of HIV dementia was used to show that viral DNA levels in the brain remained at constant levels from acute through asymptomatic infection, despite significant down-regulation of viral RNA in the brain after the acute phase of infection. Viral replication in the brain coincided with activation of macrophages and microglia in the central nervous system; down-regulation of viral replication coincided with increased infiltration of cytotoxic lymphocytes and reduced activation of macrophages and microglia in the brain. Comparison of viral genotypes in the central nervous system and peripheral blood mononuclear cells suggests that recrudescence of viral replication in brain occurs by reactivation of latent viral DNA. Latent virus in the brain must be considered in therapeutic strategies to eliminate HIV from infected persons.

Axonal damage represented by accumulation of [beta]-amyloid precursor protein ([beta]-APP) develops in numerous central nervous system (CNS) diseases including human immunodeficiency virus (HIV) infection. To study the underlying mechanisms of axonal damage associated with HIV CNS infection, the amount of axonal [beta]-APP immunostaining in the corpus callosum of 24 simian immunodeficiency virus (SIV)-infected macaques and 3 control macaques was measured by computerized image analysis. The amounts of [beta]-APP accumulation were then compared with time post-inoculation, extent and character of CNS inflammation, and viral load in the CNS measured by the amount of immunohistochemical staining for the viral transmembrane protein gp41. Significant increases over control values were present in 10 of 24 SIV-infected animals. SIV encephalitis was present in 9 of the 10 animals with elevated [beta]-APP. Increases in [beta]-APP correlated most strongly with levels of SIV gp41 in the brain (p = 0.005), but significant associations with macrophage infiltration and microglial activation (p = 0.04) and infiltration by cytotoxic lymphocytes (p = 0.05) also were identified. These data demonstrate that [beta]-APP accumulation in the white matter of SIV-infected macaques develops during SIV infection in close correlation with levels of viral replication and may serve as a sensitive marker of neuronal/axonal damage mediated by viral proteins.