Publications
Department of Medicine faculty members published more than 3,000 peer-reviewed articles in 2022.
2012
2012
Household air pollution (HAP) from biomass fuels, coal, and kerosene burned in open fires, primitive stoves, and lamps causes at least 2 million deaths per year. Many of these deaths occur in children <5 years of age with pneumonia and in women with COPD, lung cancer, and cardiovascular disease. HAP is inextricably linked to poverty, with activities to obtain fuel consuming a large proportion of the time and financial resources of poor households. Thus, fewer resources used in this way means less is available for basic needs like food, education, and health care. The burden of work and the exposure to smoke, particularly during cooking, are predominantly borne by women and children. Although historically HAP has not received sufficient attention from the scientific, medical, public health, development, and policy-making communities, the tide has clearly changed with the broad-based support and launch of the Global Alliance for Clean Cookstoves in 2010. There is now considerable reason for optimism that this substantial cause of cardiorespiratory morbidity and mortality will be addressed comprehensively and definitively. Drawing on our experience from four continents, we provide background information on the problem of HAP, health impacts of HAP, opportunities for research, and the current best solutions.
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OBJECTIVES
To determine whether intensification with raltegravir improves endothelial function in antiretroviral-treated HIV-infected individuals.
DESIGN
: Randomized, double-blinded, placebo-controlled study.
METHODS
Fifty-six subjects with treatment-mediated viral suppression for at least 1 year were randomized to add 400 mg of raltegravir twice daily or matching placebo for 24 weeks. The primary endpoint was the difference in rate of change in endothelial function [as assessed by flow-mediated vasodilation (FMD) of the brachial artery] from baseline to week 24 between the raltegravir and placebo groups. Linear mixed models were used to evaluate the association of treatment group with changes in FMD, immune activation, and measures of viral persistence.
RESULTS
At baseline, the median CD4 T-cell count was 498 cells/mm, nadir CD4 T-cell count was 191 cells/mm, duration of HIV infection was 18 years, FMD was 3.3%, and hyperemic velocity (a marker of microvascular function) was 68.3 cm. There were no significant differences between treatment groups in rate of change in FMD (raltegravir group: +0.032% per week, placebo group: +0.023% per week; P = 0.60). There were also no differences between treatment groups in rate of change in hyperemic velocity, immune activation, or viral persistence. In multivariable analysis, older age, longer duration of HIV infection, and current abacavir use were associated with lower FMD. Lower CD4 T-cell count and current abacavir use were associated with lower hyperemic velocity.
CONCLUSIONS
The addition of raltegravir to suppressive antiretroviral therapy did not have a significant impact on cardiovascular risk, as assessed by endothelial function (ClinicalTrials.gov NCT00843713).
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OBJECTIVE
Recent clinical trials in lupus nephritis have all used different criteria to assess complete response. The objective of this analysis was to compare several previously proposed criteria, using the same data set from a large trial of abatacept in lupus nephritis (IM101075). In so doing, we sought to determine which criteria are most sensitive to differences among treatment groups and to further examine the potential of abatacept in lupus nephritis.
METHODS
Patients in the IM101075 trial received abatacept at 1 of 2 different dose regimens or placebo, both on a background of mycophenolate mofetil and corticosteroids. Using data from this trial, we assessed rates of complete response at 12 months according to 5 sets of criteria, from 1) the trial protocol, 2) the Aspreva Lupus Management Study (ALMS) trial of mycophenolate mofetil, 3) the Lupus Nephritis Assessment with Rituximab (LUNAR) trial of rituximab, 4) an ongoing National Institutes of Health trial of abatacept (Abatacept and Cyclophosphamide Combination: Efficacy and Safety Study [ACCESS]), and 5) published recommendations of the American College of Rheumatology.
RESULTS
According to the complete response definition from the IM101075 study protocol, there was no difference among treatment groups in the IM101075 study. In contrast, according to the ALMS, LUNAR, and ACCESS criteria, rates of complete response among patients in the IM101075 study were higher in both treatment groups relative to control. The largest differences were obtained with use of the LUNAR criteria (complete response rate of 6% in the control group, compared to 22% and 24% in the 2 abatacept groups).
CONCLUSION
The choice of definition of complete response can determine whether a lupus nephritis trial is interpreted as a success or a failure. The results of this analysis provide an evidence-based rationale for choosing among alternative definitions and offer a strong rationale for conducting further studies of abatacept in lupus nephritis.
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Increased osteoclastic bone resorption leads to periarticular erosions and systemic osteoporosis in RA patients. Although a great deal is known about how osteoclasts differentiate from precursors and resorb bone, the identity of an osteoclast precursor (OCP) population in vivo and its regulatory role in RA remains elusive. Here, we report the identification of a CD11b(-/lo)Ly6C(hi) BM population with OCP activity in vitro and in vivo. These cells, which can be distinguished from previously characterized precursors in the myeloid lineage, display features of both M1 and M2 monocytes and expand in inflammatory arthritis models. Surprisingly, in one mouse model of RA (adoptive transfer of SKG arthritis), cotransfer of OCP with SKG CD4+ T cells diminished inflammatory arthritis. Similar to monocytic myeloid-derived suppressor cells (M-MDSCs), OCPs suppressed CD4+ and CD8+ T cell proliferation in vitro through the production of NO. This study identifies a BM myeloid precursor population with osteoclastic and T cell-suppressive activity that is expanded in inflammatory arthritis. Therapeutic strategies that prevent the development of OCPs into mature bone-resorbing cells could simultaneously prevent bone resorption and generate an antiinflammatory milieu in the RA joint.
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By characterizing the geographic and functional spectrum of human genetic variation, the 1000 Genomes Project aims to build a resource to help to understand the genetic contribution to disease. Here we describe the genomes of 1,092 individuals from 14 populations, constructed using a combination of low-coverage whole-genome and exome sequencing. By developing methods to integrate information across several algorithms and diverse data sources, we provide a validated haplotype map of 38 million single nucleotide polymorphisms, 1.4 million short insertions and deletions, and more than 14,000 larger deletions. We show that individuals from different populations carry different profiles of rare and common variants, and that low-frequency variants show substantial geographic differentiation, which is further increased by the action of purifying selection. We show that evolutionary conservation and coding consequence are key determinants of the strength of purifying selection, that rare-variant load varies substantially across biological pathways, and that each individual contains hundreds of rare non-coding variants at conserved sites, such as motif-disrupting changes in transcription-factor-binding sites. This resource, which captures up to 98% of accessible single nucleotide polymorphisms at a frequency of 1% in related populations, enables analysis of common and low-frequency variants in individuals from diverse, including admixed, populations.
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Understanding the metabolic, transporter, and genetic influences on the disposition of drugs used in chemotherapy is critical to individualization of drug therapy. Recognition of the importance of transporter-enzyme interplay, in which genetic variants of drug uptake transporters can change drug metabolism when the enzymes are unchanged, is an important advance in predicting appropriate drug dosage regimens for the individual patient.
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Hemophagocytic lymphohistiocytosis (HLH) is a rare, life-threatening inflammatory disorder characterized by uncontrolled proliferation and activation of histiocytes with phagocytosis of normal hematopoietic cells. A 41-year-old woman, 19 weeks pregnant with twins, and a history of Still's disease, presented with rash, fever, and headache. Laboratory studies revealed transaminitis, hyperbilirubinemia, and eventually severe neutropenia as well as elevations in ferritin, lactate dehydrogenase, and C-reactive protein. A bone marrow biopsy confirmed HLH. She declined standard HLH-treatment but responded well to high-dose corticosteroids. Her blood counts remained stable following corticosteroid taper, and she delivered healthy twin girls at 30-week gestation. Few cases of HLH during pregnancy have been reported. In some cases, the condition has proved fatal. Therefore recognizing signs and symptoms of HLH is essential to avoid treatment delay. In our case, high-dose corticosteroids alone were a safe and effective therapy for the mother and fetuses resulting in long-term disease control.
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BACKGROUND
Contraceptives are among the most commonly prescribed medications used by women of reproductive age, but little is known about women's information-seeking behavior after receiving prescriptions for medication.
STUDY DESIGN
All reproductive-age women who visited one of four primary care clinics in Western Pennsylvania between October 2008 and April 2010 were invited to complete a follow-up survey after their visit which included questions regarding medications prescribed, information-seeking after their visit and their perceptions of the quality of the information they found.
RESULTS
Of the 218 women prescribed contraceptives, 49% sought additional information after their visit. In models adjusted for sociodemographic and reproductive characteristics of the respondents, women who received a contraceptive prescription were twice as likely to seek additional information about their medication as women who received noncontraceptive prescriptions [odds ratio (OR)=2.06, 95% confidence interval (CI) 1.47-2.90]. Women who received a contraceptive prescription were more likely to seek information from the Internet (OR=1.84, 95% CI 1.26-2.70) and from the package insert (OR=1.55, 95% CI 1.02-2.36) than women who received noncontraceptive prescriptions.
CONCLUSIONS
Women frequently sought additional information on contraceptive prescriptions. Efforts are needed to increase the quantity and improve the quality of contraceptive counseling provided by primary care providers and the quality of the information provided by package inserts and the Internet.
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