The publication data currently available has been vetted by Vanderbilt faculty, staff, administrators and trainees. The data itself is retrieved directly from NCBI's PubMed and is automatically updated on a weekly basis to ensure accuracy and completeness.
If you have any questions or comments, please contact us.
The potential long-term association between carbohydrate intake and the risk of coronary heart disease (CHD) remains unclear, especially among populations who habitually have high-carbohydrate diets. We prospectively examined intakes of carbohydrates and staple grains as well as glycemic index and glycemic load in relation to CHD among 117,366 Chinese women and men (40-74 years of age) without history of diabetes, CHD, stroke, or cancer at baseline in Shanghai, China. Diet was assessed using validated food frequency questionnaires. Incident CHD cases were ascertained during follow-ups (in women, the mean was 9.8 years and in men, the mean was 5.4 years) and confirmed by medical records. Carbohydrate intake accounted for 67.5% of the total energy intake in women and 68.5% in men. Seventy percent of total carbohydrates came from white rice and 17% were from refined wheat products. Positive associations between carbohydrate intakess and CHD were found in both sexes (all P for heterogeneity > 0.35). The combined multivariate-adjusted hazard ratios for the lowest to highest quartiles of carbohydrate intake, respectively, were 1.00, 1.38, 2.03, and 2.88 (95% confidence interval: 1.44, 5.78; P for trend = 0.001). The combined hazard ratios comparing the highest quartile with the lowest were 1.80 (95% confidence interval: 1.01, 3.17) for refined grains and 1.87 (95% confidence interval: 1.00, 3.53) for glycemic load (both P for trend = 0.03). High carbohydrate intake, mainly from refined grains, is associated with increased CHD risk in Chinese adults.
BACKGROUND - Brain development follows a different trajectory in children with autism spectrum disorders (ASD) than in typically developing children. A proxy for neurodevelopment could be head circumference (HC), but studies assessing HC and its clinical correlates in ASD have been inconsistent. This study investigates HC and clinical correlates in the Simons Simplex Collection cohort.
METHODS - We used a mixed linear model to estimate effects of covariates and the deviation from the expected HC given parental HC (genetic deviation). After excluding individuals with incomplete data, 7225 individuals in 1891 families remained for analysis. We examined the relationship between HC/genetic deviation of HC and clinical parameters.
RESULTS - Gender, age, height, weight, genetic ancestry, and ASD status were significant predictors of HC (estimate of the ASD effect = .2 cm). HC was approximately normally distributed in probands and unaffected relatives, with only a few outliers. Genetic deviation of HC was also normally distributed, consistent with a random sampling of parental genes. Whereas larger HC than expected was associated with ASD symptom severity and regression, IQ decreased with the absolute value of the genetic deviation of HC.
CONCLUSIONS - Measured against expected values derived from covariates of ASD subjects, statistical outliers for HC were uncommon. HC is a strongly heritable trait, and population norms for HC would be far more accurate if covariates including genetic ancestry, height, and age were taken into account. The association of diminishing IQ with absolute deviation from predicted HC values suggests HC could reflect subtle underlying brain development and warrants further investigation.
© 2013 Society of Biological Psychiatry.
Pancreatic multipotent progenitor cells (MPCs) produce acinar, endocrine and duct cells during organogenesis, but their existence and location in the mature organ remain contentious. We used inducible lineage-tracing from the MPC-instructive gene Ptf1a to define systematically in mice the switch of Ptf1a(+) MPCs to unipotent proacinar competence during the secondary transition, their rapid decline during organogenesis, and absence from the mature organ. Between E11.5 and E15.5, we describe tip epithelium heterogeneity, suggesting that putative Ptf1a(+)Sox9(+)Hnf1β(+) MPCs are intermingled with Ptf1a(HI)Sox9(LO) proacinar progenitors. In the adult, pancreatic duct ligation (PDL) caused facultative reactivation of multipotency factors (Sox9 and Hnf1β) in Ptf1a(+) acini, which undergo rapid reprogramming to duct cells and longer-term reprogramming to endocrine cells, including insulin(+) β-cells that are mature by the criteria of producing Pdx1(HI), Nkx6.1(+) and MafA(+). These Ptf1a lineage-derived endocrine/β-cells are likely formed via Ck19(+)/Hnf1β(+)/Sox9(+) ductal and Ngn3(+) endocrine progenitor intermediates. Acinar to endocrine/β-cell transdifferentiation was enhanced by combining PDL with pharmacological elimination of pre-existing β-cells. Thus, we show that acinar cells, without exogenously introduced factors, can regain aspects of embryonic multipotentiality under injury, and convert into mature β-cells.
Prostate enlargement is common with aging and obesity. We investigated the association between obesity and prostate cancer controlling for differential detection related to prostate enlargement. In an analysis of 500 men, we found body mass index, waist-hip ratio, and blood leptin levels were significantly associated with high-grade PC, but only among men without prostate enlargement. Leptin was also significantly associated with high-grade prostatic intraepithelial neoplasia (HGPIN) in the absence of prostate enlargement. Our results suggest obesity advances prostate carcinogenesis, and that detection biases at prostate biopsy may explain past inconsistencies in the association between obesity and PC.
Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.
BACKGROUND - Whether soy food consumption may protect against coronary heart disease (CHD) remains controversial. No previous study has used biomarkers of soy intake in assessing the relationship between soy consumption and CHD. Biomarkers that reflect both intake and metabolism may be more informative than self-reports of dietary intake.
METHODS - We examined associations of urinary isoflavonoids, a biomarker of soy or soy isoflavone intake, with risk of CHD in a case-control study nested within two prospective cohort studies of Chinese adults in Shanghai. Cases were defined as subjects with no history of CHD at baseline who developed incident CHD during follow-up. Control subjects were randomly selected from those who remained free of CHD and matched to cases by sex, age, date and time of sample collection and antibiotic use. Baseline urinary isoflavonoids (daidzein, genistein, glycitein, equol, O-desmethylangolensin, dihydrodaidzein and dihydrogenistein) were compared between cases (n = 377) and control subjects (n = 753). Conditional logistic regression was used to evaluate the associations.
RESULTS - Total urinary isoflavonoids were not associated with CHD in either women or men. However, urinary equol excretion showed a significant inverse association with CHD in women. The adjusted odds ratios (95% confidence intervals) for CHD across increasing quartiles of equol levels in women were 1 (reference), 0.61 (0.32, 1.15), 0.51 (0.26, 0.98) and 0.46 (0.24, 0.89) (P = 0.02 for trend).
CONCLUSIONS - Our study suggests for the first time that equol, a bioactive metabolite of soy isoflavone daidzein, may be inversely associated with risk of CHD in women.
BACKGROUND - Although several studies have evaluated the relationship between adult height and mortality, their results have not been entirely consistent. Little is known about components of adult height in relation to mortality, particularly in developing countries.
METHODS - We examined the association of adult height and its components (leg and trunk length) with mortality using data from 74 869 Chinese women and 61,333 men in the Shanghai Women's (1996-2008) and Men's (2002-2008) Health Studies. Anthropometric measurements, including standing and sitting height and weight, were taken at baseline by trained interviewers according to a standard protocol. Deaths were ascertained by biennial home visits and linkage with the vital statistics registry. Cox regression models were used to evaluate the associations.
RESULTS - Neither height nor its components were associated with all-cause mortality. Height and, less consistently, its components were positively associated with cancer mortality, but inversely associated with cardiovascular disease (CVD) mortality. Hazard ratios (HRs) [95% confidence intervals (CIs)] for cancer mortality per 1-SD increment in height, trunk and leg length were 1.06 (1.01-1.12), 1.07 (1.01-1.12) and 1.03 (0.98-1.08), respectively, in women, and 1.13 (1.05-1.22), 1.09 (1.00-1.19) and 1.10 (1.03-1.16), respectively, in men. The corresponding HRs for CVD mortality were 0.89 (0.84-0.95), 0.93 (0.87-0.99) and 0.91 (0.86-0.98) in women, and 0.93 (0.86-1.02), 0.89 (0.81-0.98) and 0.99 (0.92-1.06) in men.
CONCLUSIONS - Our results suggest that different mechanisms may be involved in linking height and its components with cancer and CVD mortality.
Plasticity in growth and reproductive behavior is found in many vertebrate species, but is common in male teleost fish. Typically, "bourgeois" males are considerably larger and defend breeding territories while "parasitic" variants are small and use opportunistic breeding strategies. The P locus mediates this phenotypic variation in Xiphophorus and encodes variant alleles of the melanocortin-4 receptor (MC4R). However, deletion of the MC4R has modest effects on somatic growth and reproduction in mammals, suggesting a fundamental difference in the neuroendocrine function of central melanocortin signaling in teleosts. Here we show in a teleost that the hypothalamic pro-opiomelanocortin and AgRP neurons are hypophysiotropic, projecting to the pituitary to coordinately regulate multiple pituitary hormones. Indeed, AgRP-mediated suppression of MC4R appears essential for early larval growth. This identifies the mechanism by which the central melanocortin system coordinately regulates growth and reproduction in teleosts and suggests it is an important anatomical substrate for evolutionary adaptation.
Copyright © 2012 Elsevier Inc. All rights reserved.
OBJECTIVES - 1) describe and determine the feasibility of using cell-phone-based ecological momentary assessment (EMA) to measure blood glucose monitoring and insulin administration in adolescent Type 1 diabetes, 2) relate EMA to traditional self-report and glycemic control, and 3) identify patterns of adherence by time of day and over time using EMA.
METHOD - Adolescents with Type 1 diabetes (n = 96) completed baseline measures of cell phone use and adherence. Glycemic control (measured by levels of HbA1c) was obtained from medical records. A subgroup of adolescents (n = 50) completed 10 days of EMA to assess blood glucose monitoring frequency, timing of glucose monitoring, insulin administration, and insulin dosing. One third of adolescents were not allowed to use their cell phones for diabetes at school. Parental restrictions on cell phone use at home were not prevalent.
RESULTS - The EMA response rate (59%) remained stable over the 10-day calling period. Morning time was associated with worse monitoring and insulin administration, accounting for 59-74% of missed self-care tasks. EMA-reported missed glucose checks and missed insulin doses were correlated to traditional self-report data, but not to HbA1c levels. Trajectory analyses identified two subgroups: one with consistently adequate adherence, and one with more variable, and worse, adherence. The latter adherence style showed worse glycemic control.
CONCLUSION - Mobile phones provide a feasible method to measure glucose monitoring and insulin administration in adolescents, given a limited assessment duration. The method provided novel insights regarding patterns of adherence and should be explored in clinical settings for targeting or tailoring interventions.
The collection and sharing of person-specific biospecimens has raised significant questions regarding privacy. In particular, the question of identifiability, or the degree to which materials stored in biobanks can be linked to the name of the individuals from which they were derived, is under scrutiny. The goal of this paper is to review the extent to which biospecimens and affiliated data can be designated as identifiable. To achieve this goal, we summarize recent research in identifiability assessment for DNA sequence data, as well as associated demographic and clinical data, shared via biobanks. We demonstrate the variability of the degree of risk, the factors that contribute to this variation, and potential ways to mitigate and manage such risk. Finally, we discuss the policy implications of these findings, particularly as they pertain to biobank security and access policies. We situate our review in the context of real data sharing scenarios and biorepositories.
The full range of fracture risk determinants arise from each hierarchical level comprising the organization of bone. Raman spectroscopy is one tool capable of characterizing the collagen and mineral phases at a near submicron-length scale, but the ability of Raman spectra to distinguish compositional differences of bone is not well defined. Therefore, we analyzed multiple Raman peak intensities and peak ratios to characterize their ability to distinguish between the typically less mineralized osteonal tissue and the more mineralized interstitial tissue in intracortical human bone. To further assess origins of variance, we collected Raman spectra from embedded specimens and for two orientations of cut. Per specimen, Raman peak intensities or ratios were averaged among multiple sites within five osteons and five neighboring interstitial tissue. The peak ratios of ν(1) phosphate (PO(4)) to proline or amide III detected the highest increases of 15.4 or 12.5%, respectively, in composition from osteonal to interstitial tissue. The coefficient of variance was less than 5% for each as opposed to a value of ~8% for the traditional ν(1)PO(4)/amide I, a peak ratio that varied the most between transverse and longitudinal cuts for each tissue type. Although embedding affected Raman peaks, it did not obscure differences in most peak ratios related to mineralization between the two tissue types. In studies with limited sample size but sufficient number of Raman spectra per specimen for spatial averaging, ν(1)PO(4)/amide III or ν(1)PO(4)/proline is the Raman property that is most likely to detect a compositional difference between experimental groups.