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2010
OBJECTIVE
To determine whether raltegravir-containing antiretroviral therapy (ART) intensification reduces HIV levels in the gut.
DESIGN
Open-label study in HIV-positive adults on ART with plasma HIV RNA below 40 copies/ml.
METHODS
Seven HIV-positive adults received 12 weeks of ART intensification with raltegravir alone or in combination with efavirenz or darunavir. Gut cells were obtained by upper and lower endoscopy with biopsies from duodenum, ileum, colon, and rectum at baseline and 12 weeks. Study outcomes included plasma HIV RNA, HIV DNA and RNA from peripheral blood mononuclear cells (PBMC) and four gut sites, T-cell subsets, and activation markers.
RESULTS
Intensification produced no consistent decrease in HIV RNA in the plasma, PBMC, duodenum, colon, or rectum. However, five of seven participants had a decrease in unspliced HIV RNA per 10 CD4(+) T cells in the ileum. There was a trend towards decreased T-cell activation in all sites, which was greatest for CD8(+) T cells in the ileum and PBMC, and a trend towards increased CD4(+) T cells in the ileum.
CONCLUSION
Most HIV RNA and DNA in the blood and gut is not the result of ongoing replication that can be impacted by short-term intensification with raltegravir. However, the ileum may support ongoing productive infection in some patients on ART, even if the contribution to plasma RNA is not discernible.
View on PubMed2010
2010
2010
Little is known about electrocardiographic (ECG) characteristics of menopausal women with or at increased risk of coronary heart disease (CHD). Data from 10,101 participants in the Raloxifene Use for The Heart (RUTH) trial were used to correlate baseline ECG abnormalities with clinical characteristics. Baseline characteristics that were statistically significantly associated (p ≤ 0.05) with ECG findings in univariate analyses were used to derive multivariate model selection. Of 59% normal electrocardiograms, 50% were from women with CHD and 69% from women at increased risk of CHD. In the women with CHD, 59% reported a previous myocardial infarction (MI); 43% had a normal electrocardiogram, and 49% had a definite ECG Q-wave MI. Women in the increased-risk group had not reported a previous MI, yet 11% had a definite ECG Q-wave MI. Of women reporting hypertension, 35% had ECG evidence of left ventricular hypertrophy, but 58% did not have an abnormal electrocardiogram. Significantly more women with diabetes in the increased-risk and documented CHD cohorts had abnormal electrocardiograms (p < 0.01 for the 2 cohorts). Percent abnormal electrocardiograms increased with increasing age (55 to 64, 65 to 74, and ≥ 75 years, p < 0.01) in all cohorts. Angina and coronary artery bypass graft surgery, but not percutaneous coronary intervention, predicted an abnormal electrocardiogram. In conclusion, there were high percentages of normal electrocardiograms in the increased-risk and documented CHD groups of RUTH participants, with substantial discrepancy between MI history and ECG MI documentation, and increasing age was the predominant correlate with an abnormal electrocardiogram in all 3 cohorts.
View on PubMed2010
BACKGROUND
The gut is a major reservoir for human immunodeficiency virus (HIV) in patients receiving antiretroviral therapy (ART). We hypothesized that distinct immune environments within the gut may support varying levels of HIV.
METHODS
In 8 HIV-1-positive adults who were receiving ART and had CD4(+) T cell counts of >200 cells/μL and plasma viral loads of <40 copies/mL, levels of HIV and T cell activation were measured in blood samples and endoscopic biopsy specimens from the duodenum, ileum, ascending colon, and rectum.
RESULTS
HIV DNA and RNA levels per CD4(+) T cell were higher in all 4 gut sites compared with those in the blood. HIV DNA levels increased from the duodenum to the rectum, whereas the median HIV RNA level peaked in the ileum. HIV DNA levels correlated positively with T cell activation markers in peripheral blood mononuclear cells (PBMCs) but negatively with T cell activation markers in the gut. Multiply spliced RNA was infrequently detected in gut, and ratios of unspliced RNA to DNA were lower in the colon and rectum than in PBMCs, which reflects paradoxically low HIV transcription, given the higher level of T cell activation in the gut.
CONCLUSIONS
HIV DNA and RNA are both concentrated in the gut, but the inverse relationship between HIV DNA levels and T cell activation in the gut and the paradoxically low levels of HIV expression in the large bowel suggest that different processes drive HIV persistence in the blood and gut.
TRIAL REGISTRATION
ClinicalTrials.gov identifier: NCT00884793 (PLUS1).
View on PubMed2010
2010
2010
The marine neurotoxin domoic acid (DA) is a rigid analogue of the neurotransmitter glutamate and a potent agonist of kainate subtype glutamate receptors. Persistent activation of these receptor subtypes results in rapid excitotoxicity, calcium-dependent cell death, and neuronal degeneration in regions of the brain where glutamatergic pathways are concentrated. Previous work has shown that DA promotes the expression of inflammatory genes in the brain, such as cyclooxygenase 2 (COX2). To investigate the impact of inflammation on the development of neurodegeneration, and ultimately survival following DA administration, we used selective (L745337, Merck) and non-selective (acetylsalicylic acid (ASA)) COX inhibitors in DA exposed mice. Adult male ICR mice were given a regime of either ASA or L23547 both before and after a single LD50 dose of DA. Mice were observed immediately after toxin introduction and then sacrificed at 2 days post exposure. Our lower dose of L23547 increased survival and was most effective at decreasing neuronal degeneration in the CA1 and CA3 regions of the hippocampus, areas especially sensitive to DA excitotoxicity. This study shows that COX2 plays a role in DA induced neurodegeneration and death, and that inhibitors may be of value for treatment in human and wildlife DA exposure.
View on PubMed