Publications
Department of Medicine faculty members published more than 3,000 peer-reviewed articles in 2022.
2010
2010
2010
BACKGROUND
Many resource-constrained countries now train non-physician clinicians in HIV/AIDS care, a strategy known as 'task-shifting.' There is as yet no evidence-based international standard for training these cadres. In 2007, the Mozambican Ministry of Health (MOH) conducted a nationwide evaluation of the quality of care delivered by non-physician clinicians (técnicos de medicina, or TMs), after a two-week in-service training course emphasizing antiretroviral therapy (ART).
METHODS
Forty-four randomly selected TMs were directly observed by expert clinicians as they cared for HIV-infected patients in their usual worksites. Observed clinical performance was compared to national norms as taught in the course.
RESULTS
In 127 directly observed patient encounters, TMs assigned the correct WHO clinical stage in 37.6%, and correctly managed co-trimoxazole prophylaxis in 71.6% and ART in 75.5% (adjusted estimates). Correct management of all 5 main aspects of patient care (staging, co-trimoxazole, ART, opportunistic infections, and adverse drug reactions) was observed in 10.6% of encounters.The observed clinical errors were heterogeneous. Common errors included assignment of clinical stage before completing the relevant patient evaluation, and initiation or continuation of co-trimoxazole or ART without indications or when contraindicated.
CONCLUSIONS
In Mozambique, the in-service ART training was suspended. MOH subsequently revised the TMs' scope of work in HIV/AIDS care, defined new clinical guidelines, and initiated a nationwide re-training and clinical mentoring program for these health professionals. Further research is required to define clinically effective methods of health-worker training to support HIV/AIDS care in Mozambique and similarly resource-constrained environments.
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
BACKGROUND
Macrophages contribute to the progression and acute complications of atherosclerosis. Macrophage imaging may serve as a biomarker to identify subclinical inflamed lesions, to predict future risk, and to aid in the assessment of novel therapies.
METHODS AND RESULTS
To test the hypothesis that nanoparticle-enhanced, high-resolution magnetic resonance imaging (MRI) can measure plaque macrophage accumulation, we used 3-T MRI with a macrophage-targeted superparamagnetic nanoparticle preparation (monocrystalline iron oxide nanoparticles-47 [MION-47]) in cholesterol-fed New Zealand White rabbits 6 months after balloon injury. In vivo MRI visualized thickened abdominal aortas on both T1- and T2-weighted spin-echo images (T1 spin echo, 20 axial slices per animal; T2 spin echo, 28 slices per animal). Seventy-two hours after MION-47 injection, aortas exhibited lower T2 signal intensity compared with before contrast imaging (signal intensity ratio, aortic wall/muscle: before, 1.44 ± 0.26 versus after, 0.95 ± 0.22; 164 slices; P<0.01), whereas T1 spin echo images showed no significant change. MRI on ex vivo specimens provided similar results. Histological studies colocalized iron accumulation with immunoreactive macrophages in atheromata. The magnitude of signal intensity reduction on T2 spin echo in vivo images further correlated with macrophage areas in situ (150 slices; r=0.73). Treatment with rosuvastatin for 3 months yielded diminished macrophage content (P<0.05) and reversed T2 signal intensity changes (P<0.005). Signal changes in rosuvastatin-treated rabbits correlated with reduced macrophage burden (r=0.73). In vitro validation studies showed concentration-dependent MION-47 uptake by human primary macrophages.
CONCLUSION
The magnitude of T2 signal intensity reduction in high-resolution MRI after administration of superparamagnetic phagocytosable nanoparticles can assess macrophage burden in atheromata, providing a clinically translatable tool to identify inflamed plaques and to monitor therapy-mediated changes in plaque inflammation.
View on PubMed2010
2010
2010