Publications
Department of Medicine faculty members published more than 3,600 peer-reviewed articles in 2024.
2013
INTRODUCTION
We sought to determine the effects of brief exposures to low concentrations of tobacco secondhand smoke (SHS) on arterial flow-mediated dilation (FMD, a nitric oxide-dependent measure of vascular endothelial function), in a controlled animal model never before exposed to smoke. In humans, SHS exposure for 30 min impairs FMD. It is important to gain a better understanding of the acute effects of exposure to SHS at low concentrations and for brief periods of time.
METHODS
We measured changes in FMD in rats exposed to a range of real-world levels of SHS for durations of 30 min, 10 min, 1 min, and 4 breaths (roughly 15 s).
RESULTS
We observed a dose-response relationship between SHS particle concentration over 30 min and post-exposure impairment of FMD, which was linear through the range typically encountered in smoky restaurants and then saturated at higher concentrations. One min of exposure to SHS at moderate concentrations was sufficient to impair FMD.
CONCLUSIONS
Brief SHS exposure at real-world levels reversibly impairs FMD. Even 1 min of SHS exposure can cause reduction of endothelial function.
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2013
2013
BACKGROUND
Chronic disease registries have been successful at promoting the delivery of guideline-concordant primary care for patients with diabetes and hypertension, but not for chronic kidney disease (CKD). To understand whether a registry could be designed to improve CKD management in primary care, we explored primary care provider attitudes about the benefits (or lack thereof) of a CKD registry compared with other chronic diseases and the key facilitators of successfully implementing a CKD registry in safety-net primary care.
STUDY DESIGN
Qualitative, using semistructured interviews.
SETTING & PARTICIPANTS
We conducted and recorded semistructured 1-hour interviews with medical directors and quality improvement champions from safety-net adult primary care clinics in San Francisco.
ANALYTIC APPROACH
Recordings were transcribed and analyzed using a grounded theory approach until thematic saturation was achieved.
RESULTS
20 primary care providers were interviewed. 4 themes relevant to the development of a successful CKD registry for safety-net primary care were identified: (1) provider beliefs that a CKD registry could aid in the delivery of team-based high-quality CKD care; (2) clinic workflow redesign and staffing are key facilitators to successful implementation of a CKD registry; (3) unique complexities of CKD, such as varying etiologies, may limit the use of a CKD registry by nonphysicians; and (4) a CKD registry is aligned with current primary care priorities and health care delivery strategies.
LIMITATIONS
Small sample size and reliance on clinician leaders within one health care delivery system.
CONCLUSIONS
A CKD registry directed at the entire health care team, with the functionality to track, standardize, and enhance CKD care through decision support, has the potential to improve the management of CKD in safety-net primary care settings. These data directly informed the development of a CKD registry in these settings in San Francisco.
View on PubMed2013
BACKGROUND
Identifying potentially modifiable risk factors is critically important for reducing the burden of chronic kidney disease. We sought to examine the association of body mass index (BMI) with kidney function decline in a cohort of young adults with preserved glomerular filtration at baseline.
STUDY DESIGN
Longitudinal cohort.
SETTING & PARTICIPANTS
2,839 black and white young adults with cystatin C-based estimated glomerular filtration rate (eGFRcys)>90mL/min/1.73m(2) taking part in the year-10 examination (in 1995-1996) of the Coronary Artery Risk Development in Young Adults (CARDIA) Study.
PREDICTOR
BMI, categorized as 18.5-24.9 (reference), 25.0-29.9, 30.0-39.9, and ≥40.0kg/m(2).
OUTCOMES
Trajectory of kidney function decline, rapid decline (>3% per year), and incident eGFRcys <60mL/min/1.73m(2) over 10 years of follow-up.
MEASUREMENTS
GFRcys estimated from the CKD-EPI (Chronic Kidney Disease Epidemiology Collaboration) equation for calibrated cystatin C at CARDIA years 10, 15, and 20.
RESULTS
At year 10, participants had a mean age of 35.1 years, median eGFRcys of 114mL/min/1.73m(2), and 24.5% had BMI≥30.0kg/m(2). After age 30 years, average eGFRcys was progressively lower with each increment in BMI after adjustment for baseline age, race, sex, hyperlipidemia, smoking status, and physical activity. Higher BMI category was associated with successively higher odds of rapid decline (for 25.0-29.9, 30.0-39.9, and ≥40.0kg/m(2), adjusted ORs were 1.50 [95% CI, 1.21-1.87], 2.01 [95% CI, 1.57-2.87], and 2.57 [95% CI, 1.67-3.94], respectively). 18 participants (0.6%) had incident eGFRcys<60mL/min/1.73m(2). In unadjusted analysis, higher BMI category was associated with incident eGFRcys<60mL/min/1.73m(2) (for 25.0-29.9, 30.0-39.9, and ≥40.0kg/m(2), ORs were 5.17 [95% CI, 1.10-25.38], 7.44 [95% CI, 1.54-35.95], and 5.55 [95% CI, 0.50-61.81], respectively); adjusted associations were no longer significant.
LIMITATIONS
Inability to describe kidney function before differences by BMI category were already evident. Absence of data for measured GFR or GFR estimated from serum creatinine level.
CONCLUSIONS
Higher BMI categories are associated with greater declines in kidney function in a cohort of young adults with preserved GFR at baseline. Clinicians should vigilantly monitor overweight and obese patients for evidence of early kidney function decline.
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The cytokine TGF-β plays an integral role in regulating immune responses. TGF-β has pleiotropic effects on adaptive immunity, especially in the regulation of effector and regulatory CD4(+) T cell responses. Many immune and nonimmune cells can produce TGF-β, but it is always produced as an inactive complex that must be activated to exert functional effects. Thus, activation of latent TGF-β provides a crucial layer of regulation that controls TGF-β function. In this review, we highlight some of the important functional roles for TGF-β in immunity, focusing on its context-specific roles in either dampening or promoting T cell responses. We also describe how activation of TGF-β controls its function in the immune system, with a focus on the key roles for members of the integrin family in this process.
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2013
Positron emission tomography-magnetic resonance imaging (PET/MRI) is emerging as a novel diagnostic modality with exciting potential for a role in multiple cardiovascular applications. The combination of the high sensitivity of PET tracers with the excellent spatial resolution and tissue characterization of cardiac MRI will provide complementary information in a variety of cardiac pathologies. While initial efforts have focused on the combination of MRI and PET for assessment of coronary artery disease, cardiomyopathy, viability, and inflammation, this new technology holds enormous potential for molecular cardiovascular imaging. This article will review the development of PET/MRI, review the current research, and discuss potential future applications.
View on PubMed2013
BACKGROUND AND AIMS
Prior studies have underlined the need for increased screening and awareness of chronic hepatitis B (CHB), especially in certain high-risk populations. However, few studies have examined the patterns of evaluation and management of CHB between primary care physicians (PCP) and specialists according to commonly-used professional guidelines. Our goal was to examine whether necessary laboratory parameters used to determine disease status and eligibility for antiviral therapy were performed by PCPs and specialists.
METHODS
We conducted a retrospective study of 253 treatment-naïve CHB patients who were evaluated by PCP only (n=63) or by specialists (n=190) for CHB at a community multispecialty medical center between March 2007 and June 2009. Criteria for CHB management and treatment eligibility were based on the American Association for the Study of Liver Diseases 2007 guideline and the US Panel 2006 algorithm. Required parameters for optimal evaluation for CHB included hepatitis B e antigen (HBeAg), HBV DNA, and alanine aminotransferase (ALT). Preferred antiviral agents for CHB included pegylated interferon, adefovir, and entecavir.
RESULTS
The majority of patients were Asians (90%) and (54%) with a mean age of 43±11.6 years. Compared to PCPs, specialists were more likely to order laboratory testing for ALT (94 vs. 86%, P=0.05), HBeAg (67 vs. 41%, P<0.0001) and HBV DNA (83 vs. 52%, P<0.0001). The proportion of patients having all three laboratory parameters was significantly higher among those evaluated by specialists compared to PCP (62 vs. 33%, P<0.0001). A total of 55 patients were initiated on antiviral treatment (n=47 by specialists and n=6 by PCPs). Lamivudine was prescribed more often by PCPs than specialists (33 vs. 2%, P=0.05). Preferred agents were used 96% of the time by specialists compared to 67% of those treated by PCPs (P=0.05).
CONCLUSION
Patients evaluated by specialists for CHB are more likely to undergo more complete laboratory evaluation and, if eligible, are also more likely to be treated with preferred longer-term agents for CHB compared to those evaluated by PCPs only. A collaborative model of care involving both PCP and specialists may further optimize management of patients with CHB.
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The incidence of hepatocellular carcinoma (HCC) is higher in Asian Americans than in other ethnicities. While hepatitis B virus (HBV) is common, hepatitis C virus (HCV) is more prevalent in some subgroups. Our goal was to determine the etiology of liver disease associated with HCC in subgroups of Asian Americans. This was an analysis of 510 Asian HCC patients at a US medical center. Patients were identified using ICD9 diagnosis. Multivariate logistic regression was used to study predictors of HCV as the cause of HCC. Patients were Southeast Asian, Chinese, and Korean, with similar gender, age, and foreign-born status. Southeast Asians had a similar proportion of HBV- and HCV-related HCC, while Chinese and Korean patients had a higher proportion of HBV-related HCC. HCC was usually associated with HBV in Chinese and Korean patients, but both HCV and HBV were important associations in Southeast Asians.
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