Publications
Department of Medicine faculty members published more than 3,600 peer-reviewed articles in 2024.
2014
A rare subset of HIV-infected individuals, designated viremic non-progressors (VNP), remain asymptomatic and maintain normal levels of CD4+ T-cells despite persistently high viremia. To identify mechanisms potentially responsible for the VNP phenotype, we compared VNPs (average >9 years of HIV infection) to HIV-infected individuals who have similar CD4+ T-cell counts and viral load, but who are likely to progress if left untreated ("putative progressors", PP), thus avoiding the confounding effect of differences related to substantial CD4+ T cell depletion. We found that VNPs, compared to PPs, had preserved levels of CD4+ stem cell memory cells (TSCM (p<0.0001), which was associated with decreased HIV infection of these cells in VNPs (r = -0.649, p = 0.019). In addition, VNPs had decreased HIV infection in CD4+ central memory (TCM) cells (p = 0.035), and the total number of TCM cells was associated with increased proliferation of memory CD4+ T cells (r = 0.733, p = 0.01). Our results suggest that, in HIV-infected VNPs, decreased infection of CD4+ TCM and TSCM, cells are involved in preservation of CD4+ T cell homeostasis and lack of disease progression despite high viremia.
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Insulin-like growth factor-binding protein 7 (IGFBP7) is a biomarker that has recently been associated with heart failure and cardiac hypertrophy. The aim of this study was to examine IGFBP7 relative to echocardiographic abnormalities reflecting diastolic dysfunction. One hundred twenty-four patients with ambulatory heart failure with reduced ejection fraction and baseline detailed 2-dimensional echocardiograms were followed for a mean of 10 months. IGFBP7 was measured serially at each office visit; 108 patients underwent follow-up echocardiography. Echocardiographic parameters of diastolic function were compared at baseline and over time. IGFBP7 concentrations were not linked to left ventricular size or systolic function. In contrast, those with elevated baseline IGFBP7 concentrations were more likely to have abnormalities of parameters describing diastolic function, such as higher left atrial volume index, transmitral E/A ratio, E/E' ratio, and right ventricular systolic pressure. IGFBP7 was correlated with left atrial volume index (ρ = 0.237, p = 0.008), transmitral E/A ratio (ρ = 0.304, p = 0.001), E/E' ratio (ρ = 0.257, p = 0.005), and right ventricular systolic pressure (ρ = 0.316, p = 0.001). Furthermore, each was found to be independently predictive of IGFBP7 in adjusted analysis. In subjects with baseline and final echocardiograms, more time spent with elevated IGFBP7 concentrations in serial measurement was associated with worsening diastolic function and increasing left atrial volume index or right ventricular systolic pressure. IGFBP7 concentrations were predictive of an increased risk for cardiovascular events independent of echocardiographic measures of diastolic function (p = 0.006). In conclusion, IGFBP7 is a novel prognostic biomarker for heart failure with reduced ejection fraction and shows significant links to the presence and severity of echocardiographic parameters of abnormal diastolic function.
View on PubMed2014
2014
BACKGROUND
Food insecurity, insufficient quality and quantity of nutritionally adequate food, affects millions of people in the United States (US) yearly, with over 18 million Americans reporting hunger. Food insecurity is associated with obesity in the general population. Due to the increasing prevalence of obesity and risk factors for cardiovascular disease among HIV-infected women, we sought to determine the relationship between food insecurity and obesity in this cohort of urban, HIV-infected and -uninfected but at risk women.
METHODS
Using a cross-sectional design, we collected data on food insecurity, body mass index and demographic and clinical data from 231 HIV-infected and 119 HIV-negative women enrolled in Bronx site of the Women's Interagency HIV Study (WIHS). We used multivariate logistic regression to identify factors associated with obesity.
RESULTS
Food insecurity was highly prevalent, with almost one third of women (110/350, 31%) reporting food insecurity over the previous six months and over 13% of women reported food insecurity with hunger. Over half the women were obese with a Body Mass Index (BMI) of ≥ 30. In multivariate analyses, women who were food insecure with hunger had higher odds of obesity (Adjusted odds ratio [aOR] = 2.56, 95% Confidence Interval [CI] = 1.27, 5.20) after adjusting for HIV status, age, race, household status, income, drug and alcohol use.
CONCLUSION
Food insecurity with hunger was associated with obesity in this population of HIV-infected and -uninfected, urban women. Both food insecurity and obesity are independent markers for increased mortality; further research is needed to understand this relationship and their role in adverse health outcomes.
View on PubMed2014
OBJECTIVE
Asymptomatic primary hyperparathyroidism (PHPT) is a common clinical problem. The only available definitive therapy is parathyroidectomy, which is appropriate to consider in all patients. The purpose of this report is to provide an update on calcium and vitamin D supplementation and medical management for those patients with PHPT who cannot or do not want to undergo surgery.
METHODS
Questions were developed by the International Task Force on PHPT. A comprehensive literature search was undertaken, and relevant articles published between 2008 and 2013 were reviewed in detail. The questions were addressed by the panel of experts, and consensus was established at the time of the workshop.
CONCLUSIONS
The recommended calcium intake in patients with PHPT should follow guidelines established for all individuals. It is not recommended to limit calcium intake in patients with PHPT who do not undergo surgery. Patients with low serum 25-hydroxyvitamin D should be repleted with doses of vitamin D aiming to bring serum 25-hydroxyvitamin D levels to ≥ 50 nmol/L (20 ng/mL) at a minimum, but a goal of ≥75 nmol/L (30 ng/mL) also is reasonable. Pharmacological approaches are available and should be reserved for those patients in whom it is desirable to lower the serum calcium, increase BMD, or both. For the control of hypercalcemia, cinacalcet is the treatment of choice. Cinacalcet reduces serum calcium concentrations to normal in many cases, but has only a modest effect on serum PTH levels. However, bone mineral density (BMD) does not change. To improve BMD, bisphosphonate therapy is recommended. The best evidence is for the use of alendronate, which improves BMD at the lumbar spine without altering the serum calcium concentration. To reduce the serum calcium and improve BMD, combination therapy with both agents is reasonable, but strong evidence for the efficacy of that approach is lacking.
View on PubMed2014
OBJECTIVE
Asymptomatic primary hyperparathyroidism (PHPT) is a common clinical problem. The purpose of this report is to provide an update on the use of diagnostic tests for this condition in clinical practice.
PARTICIPANTS
This subgroup was constituted by the Steering Committee to address key questions related to the diagnosis of PHPT. Consensus was established at a closed meeting of the Expert Panel that followed.
EVIDENCE
Each question was addressed by a relevant literature search (on PubMed), and the data were presented for discussion at the group meeting.
CONSENSUS PROCESS
Consensus was achieved by a group meeting. Statements were prepared by all authors, with comments relating to accuracy from the diagnosis subgroup and by representatives from the participating professional societies.
CONCLUSIONS
We conclude that: 1) reference ranges should be established for serum PTH in vitamin D-replete healthy individuals; 2) second- and third-generation PTH assays are both helpful in the diagnosis of PHPT; 3) normocalcemic PHPT is a variant of the more common presentation of PHPT with hypercalcemia; 4) serum 25-hydroxyvitamin D concentrations should be measured and, if vitamin D insufficiency is present, it should be treated as part of any management course; 5) genetic testing has the potential to be useful in the differential diagnosis of familial hyperparathyroidism or hypercalcemia.
View on PubMed2014
Although clinical immunity to malaria eventually develops among children living in endemic settings, the underlying immunologic mechanisms are not known. The Vδ2(+) subset of γδ T cells have intrinsic reactivity to malaria antigens, can mediate killing of Plasmodium falciparum merozoites, and expand markedly in vivo after malaria infection in previously naïve hosts, but their role in mediating immunity in children repeatedly exposed to malaria is unclear. We evaluated γδ T cell responses to malaria among 4-year-old children enrolled in a longitudinal study in Uganda. We found that repeated malaria was associated with reduced percentages of Vδ2(+) γδ T cells in peripheral blood, decreased proliferation and cytokine production in response to malaria antigens, and increased expression of immunoregulatory genes. Further, loss and dysfunction of proinflammatory Vδ2(+) γδ T cells were associated with a reduced likelihood of symptoms upon subsequent P. falciparum infection. Together, these results suggest that repeated malaria infection during childhood results in progressive loss and dysfunction of Vδ2(+) γδ T cells that may facilitate immunological tolerance of the parasite.
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