Publications
Department of Medicine faculty members published more than 3,600 peer-reviewed articles in 2024.
2011
BACKGROUND
Since 2006, leading US cigarette companies have been promoting new snus products as line extensions of popular cigarette brands. These promotional efforts include direct mail marketing to consumers on cigarette company mailing lists. This study examines smokers' reactions to this advertising and perceptions of the new snus products.
METHODS
Eight focus groups (n=65 participants) were conducted in San Francisco and Los Angeles in 2010 with smokers who received tobacco direct mail advertising. The focus group discussions assessed smokers' perceptions of the new snus products. Focus group videos were transcribed and coded using Transana software to identify common themes.
RESULTS
Most participants were aware of snus advertising and many had tried free samples. Most were aware that snus was supposed to be 'different' from traditional chewing tobacco but consistently did not know why. Participants willing to try snus still identified strongly as smokers, and for some participants, trying snus reinforced their preference for smoking. Snus' major benefits were use in smoke-free environments and avoiding social stigma related to secondhand smoke. Participants were sceptical of the idea that snus was safer than cigarettes and did not see it as an acceptable substitute for cigarettes or as a cessation aid.
CONCLUSIONS
Smokers repeated some messages featured in early snus advertising. Snus was not seen as an acceptable substitute for smoking or way to quit cigarettes. Current smoker responses to snus advertising are not consistent with harm reduction.
View on PubMed2011
Recent studies suggest that selection can allow coexistence in situations where ecological dynamics lead to competitive exclusion, provided that there is a trade-off between traits optimal for interacting with conspecifics and traits optimal for interacting with heterospecifics. Despite compelling empirical evidence, there is no general framework for elucidating how and when selection will allow coexistence in natural communities. Here we develop such a framework for a mechanism that we term "neighbor-dependent selection." We show that this mechanism can both augment coexistence when ecological conditions allow for niche partitioning and enable coexistence when ecological conditions lead to competitive exclusion. The novel insight is that when ecological conditions lead to exclusion, neighbor-dependent selection can allow coexistence via cycles driven by an intransitive loop; selection causes one species to be a superior interspecific competitor when it is rare and an inferior interspecific competitor when it is abundant. Our framework predicts the conditions under which selection can enable coexistence, as opposed to merely augmenting it, and elucidates the effects of heritability on the eco-evolutionary feedbacks that drive coexistence. Given increasing evidence that evolution operates on ecological timescales, our approach provides one means for evaluating the role of selection and trait evolution in species coexistence.
View on PubMed2011
BACKGROUND
Pharmacogenetic testing holds major promise in allowing physicians to tailor therapy to patients based on genotype. However, there is little data on the impact of pharmacogenetic test results on patient and clinician choice of therapy. CYP2D6 testing among tamoxifen users offers a potential test case of the use of pharmacogenetic testing in the clinic. We evaluated the effect of CYP2D6 testing in clinical practice to determine whether genotype results affected choice of hormone therapy in a prospective cohort study.
METHODS
Women planning to take or currently taking tamoxifen were considered eligible. Participants were enrolled in an informational session that reviewed the results of studies of CYP2D6 genotype on breast cancer recurrence. CYP2D6 genotyping was offered to participants using the AmpliChip CYP450 Test. Women were classified as either poor, intermediate, extensive or ultra-rapid metabolizers. Results were provided to clinicians without specific treatment recommendations. Follow-up was performed with a structured phone interview 3 to 6 months after testing to evaluate changes in medication.
RESULTS
A total of 245 women were tested and 235 completed the follow-up survey. Six of 13 (46%) women classified as poor metabolizers reported changing treatment compared with 11 of 218 (5%) classified as intermediate, extensive or ultra-rapid metabolizers (P < 0.001). There was no difference in treatment choices between women classified as intermediate and extensive metabolizers. In multi-variate models that adjusted for age, race/ethnicity, educational status, method of referral into the study, prior knowledge of CYP2D6 testing, the patients' CYP2D6 genotype was the only significant factor that predicted a change in therapy (odds ratio 22.8; 95% confidence interval 5.2 to 98.8). Genetic testing did not affect use of co-medications that interact with CYP2D6.
CONCLUSIONS
CYP2D6 genotype testing led to changes in therapy among poor metabolizers, even in the absence of definitive data that an alternative medicine improved outcomes. Pharmacogenetic testing can affect choice of therapy, even in the absence of definitive data on clinical impact.
View on PubMed2011
2011
2011
2011
Ovarian autoimmunity is increasingly implicated in the etiology of primary ovarian insufficiency (POI), previously termed PREMATURE OVARIAN FAILURE or PREMATURE MENOPAUSE. Links to autoimmunity in human POI have long been noted due to the close association of POI with several autoimmune diseases and syndromes such as Addison's disease and Autoimmune polyglandular syndrome 1. However, diagnosis of autoimmune-mediated POI (aPOI) remains challenging because of the lack of sensitive or specific markers of disease. Autoimmunity can arise from the breakdown of immunological tolerance in several ways. How then may we discern what constitutes a relevant target and what represents a downstream phenomenon? The answer lies in the study of pathogenic mechanisms in translational models of disease. From examples in humans and mice, we see that ovarian autoimmunity likely arises from a limited number of antigens targeted in the ovary that are organ specific. These antigens may be conserved but not limited to those seen in animal models of autoimmune ovarian disease. Recent advances in these areas have begun to define the relevant antigens and mechanisms of immune tolerance breakdown in the ovary. Work in translational models continues to provide insight into mechanisms of disease pathogenesis that will allow more accurate diagnosis and, ultimately, improved interventions for women with aPOI.
View on PubMed2011
Proficiency in the diagnosis of nonpolypoid colorectal neoplasm yields high adenoma detection rates.
2011
BACKGROUND AND AIMS
Current efforts to prevent colorectal cancer focus on the detection and removal of neoplasms. Nonpolypoid colorectal neoplasms (NP-CRN) have a subtle appearance that can be difficult to recognize during colonoscopy. Endoscopists must first be familiar with the patterns of NP-CRN in order to detect and diagnose them. We studied the adenoma detection rates of endoscopists who had trained to detect NP-CRN, versus endoscopists who had not.
MATERIALS AND METHODS
Current efforts to prevent colorectal cancer focus on the detection and removal of neoplasms. Nonpolypoid colorectal neoplasms (NP-CRN) have a subtle appearance that can be difficult to recognize during colonoscopy. Endoscopists must first be familiar with the patterns of NP-CRN in order to detect and diagnose them. We studied the adenoma detection rates of endoscopists who had trained to detect NP-CRN, versus endoscopists who had not.
DESIGN
Retrospective Nested Case Control Study.
SETTING
Outpatient Screening Colonoscopy.
PARTICIPANTS
Adult Veterans.
INTERVENTION
Proficiency in the features and diagnosis of NP-CRN.
MAIN OUTCOMES MEASUREMENTS
Adenoma detection.
RESULTS
In total, 462 patients had screening colonoscopies-267 by colonoscopists who had trained in the features and diagnosis of NP-CRN. Patient characteristics were similar between groups-the majority were men with a mean age of 62 ± 6 years. Neoplasia was more prevalent (45.7 vs. 34.9%; p = 0.02) in patients evaluated by the trained compared to the conventionally trained group. Trained colonoscopists had a higher adenoma detection rate (0.76 vs. 0.54 adenomas per patient, p < 0.001); removed a higher proportion of neoplasia (77 vs. 35%, p < 0.001); and more frequently diagnosed NP-CRN lesions (OR 2.98, 95% CI: 1.46-6.08) compared to colonoscopists without supplemental training.
CONCLUSIONS
Endoscopists who are proficient in the detection of NP-CRN had significantly higher adenoma detection rates-of both polypoid and flat adenomas-compared to endoscopists without training, and were more specific in resection of adenomatous over hyperplastic lesions.
View on PubMed2011
Data from laboratory studies, observational research, and/or secondary prevention trials suggest that vitamin D and marine omega-3 fatty acids may reduce risk for cancer or cardiovascular disease (CVD), but primary prevention trials with adequate dosing in general populations (i.e., unselected for disease risk) are lacking. The ongoing VITamin D and OmegA-3 TriaL (VITAL) is a large randomized, double-blind, placebo-controlled, 2 x 2 factorial trial of vitamin D (in the form of vitamin D(3) [cholecalciferol], 2000 IU/day) and marine omega-3 fatty acid (Omacor fish oil, eicosapentaenoic acid [EPA]+docosahexaenoic acid [DHA], 1g/day) supplements in the primary prevention of cancer and CVD among a multi-ethnic population of 20,000 U.S. men aged ≥ 50 and women aged ≥ 55. The mean treatment period will be 5 years. Baseline blood samples will be collected in at least 16,000 participants, with follow-up blood collection in about 6000 participants. Yearly follow-up questionnaires will assess treatment compliance (plasma biomarker measures will also assess compliance in a random sample of participants), use of non-study drugs or supplements, occurrence of endpoints, and cancer and vascular risk factors. Self-reported endpoints will be confirmed by medical record review by physicians blinded to treatment assignment, and deaths will be ascertained through national registries and other sources. Ancillary studies will investigate whether these agents affect risk for diabetes and glucose intolerance; hypertension; cognitive decline; depression; osteoporosis and fracture; physical disability and falls; asthma and other respiratory diseases; infections; and rheumatoid arthritis, systemic lupus erythematosus, thyroid diseases, and other autoimmune disorders.
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