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81.

Objective

The purpose of this study was to evaluate the effect of weight loss induced in morbidly obese subjects by Roux-en-Y gastric bypass bariatric surgery on the atherogenic features of their plasma lipoproteins.

Methods

Twenty-one morbidly obese subjects undergoing bariatric surgery were followed up for up to 1 year after surgery. Plasma and lipoproteins were assayed for chemical composition and lipoprotein-associated phospholipase A2 (Lp-PLA2) activity. Lipoprotein size was assessed by non-denaturing polyacrylamide gradient gel electrophoresis, and oxidised LDL by ELISA. Liver samples were assayed for mRNA abundance of oxidative markers.

Results

Lipid profile analysis revealed a reduction in the plasma concentrations of cholesterol and triglycerides, which were mainly associated with a significant reduction in the plasma concentration of circulating apoB-containing lipoproteins rather than with changes in their relative chemical composition. All patients displayed a pattern A phenotype of LDL subfractions and a relative increase in the antiatherogenic plasma HDL-2 subfraction (>2-fold; P < 0.001). The switch towards predominantly larger HDL particles was due to an increase in their relative cholesteryl ester content. Excess weight loss also led to a significant decrease in the plasma concentration of oxidised LDL (∼−25%; P < 0.01) and in the total Lp-PLA2 activity. Interestingly, the decrease in plasma Lp-PLA2 was mainly attributed to a decrease in the apoB-containing lipoprotein-bound Lp-PLA2.

Conclusion

Our data indicate that the weight loss induced by bariatric surgery ameliorates the atherogenicity of plasma lipoproteins by reducing the apoB-containing Lp-PLA2 activity and oxidised LDL, as well as increasing the HDL-2 subfraction.  相似文献   
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Background: The association between human blood DNA global methylation and global hydroxymethylation has not been evaluated in population-based studies. No studies have evaluated environmental determinants of global DNA hydroxymethylation, including exposure to metals.Objective: We evaluated the association between global DNA methylation and global DNA hydroxymethylation in 48 Strong Heart Study participants for which selected metals had been measured in urine at baseline and DNA was available from 1989–1991 (visit 1) and 1998–1999 (visit 3).Methods: We measured the percentage of 5-methylcytosine (5-mC) and 5-hydroxymethylcytosine (5-hmC) in samples using capture and detection antibodies followed by colorimetric quantification. We explored the association of participant characteristics (i.e., age, adiposity, smoking, and metal exposure) with both global DNA methylation and global DNA hydroxymethylation.Results: The Spearman’s correlation coefficient for 5-mC and 5-hmC levels was 0.32 (p = 0.03) at visit 1 and 0.54 (p < 0.001) at visit 3. Trends for both epigenetic modifications were consistent across potential determinants. In cross-sectional analyses, the odds ratios of methylated and hydroxymethylated DNA were 1.56 (95% CI: 0.95, 2.57) and 1.76 (95% CI: 1.07, 2.88), respectively, for the comparison of participants above and below the median percentage of dimethylarsinate. The corresponding odds ratios were 1.64 (95% CI: 1.02, 2.65) and 1.16 (95% CI: 0.70, 1.94), respectively, for the comparison of participants above and below the median cadmium level. Arsenic exposure and metabolism were consistently associated with both epigenetic markers in cross-sectional and prospective analyses. The positive correlation of 5-mC and 5-hmC levels was confirmed in an independent study population.Conclusions: Our findings support that both epigenetic measures are related at the population level. The consistent trends in the associations between these two epigenetic modifications and the characteristics evaluated, especially arsenic exposure and metabolism, suggest the need for understanding which of the two measures is a better biomarker for environmental epigenetic effects in future large-scale epidemiologic studies.Citation: Tellez-Plaza M, Tang WY, Shang Y, Umans JG, Francesconi KA, Goessler W, Ledesma M, Leon M, Laclaustra M, Pollak J, Guallar E, Cole SA, Fallin MD, Navas-Acien A. 2014. Association of global DNA methylation and global DNA hydroxymethylation with metals and other exposures in human blood DNA samples. Environ Health Perspect 122:946–954; http://dx.doi.org/10.1289/ehp.1306674  相似文献   
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Neuroticism is the personality dimension most frequently associated with chronic fatigue syndrome (CFS). Most studies have also shown that CFS patients are less extraverted than non-CFS patients, but results have been inconsistent, possibly because the facets of the extraversion dimension have not been separately analyzed. This study has the following aims: to assess the personality profile of adults with CFS using the Alternative Five-Factor Model (AFFM), which considers Activity and Sociability as two separate factors of Extraversion, and to test the discriminant validity of a measure of the AFFM, the Zuckerman–Kuhlman Personality Questionnaire, in differentiating CFS subjects from normal-range matched controls. The CFS sample consisted of 132 consecutive patients referred for persistent fatigue or pain to the Department of Medicine of a university hospital. These were compared with 132 matched normal population controls. Significantly lower levels of Activity and significantly higher levels of Neuroticism-Anxiety best discriminated CFS patients from controls. The results are consistent with existing data on the relationship between Neuroticism and CFS, and clarify the relationship between Extraversion and CFS by providing new data on the relationship of Activity to CFS.  相似文献   
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The present study assesses the impact of beverage consumption pattern on diet quality and anthropometric proxy measures for abdominal adiposity in Spanish adolescents. Data were obtained from a representative national sample of 1,149 Spanish adolescents aged 10–18 years. Height, weight, and waist circumferences were measured. Dietary assessment was performed with a 24-h recall. Beverage patterns were identified by cluster analysis. Adherence to the Mediterranean diet was measured by the KIDMED index. Three beverage clusters were identified for boys—“whole milk” (62.5 %), “low-fat milk” (17.5 %) and “soft drinks” (20.1 %)—and for girls—whole milk” (57.8 %), “low-fat milk” (20.8 %) and juice (21.4 %), accounting for 8.3, 9.6, 13.9, 8.6, 11.5 and 12.9 % of total energy intake, respectively. Each unit of increase in the KIDMED index was associated with a 14.0 % higher (p?=?0.004) and 11.0 % lower (p?=?0.048) probability of membership in the “low-fat milk” and “soft drinks” cluster in girls and boys, respectively, compared with the “whole milk” cluster. Boys in the “soft drinks” cluster had a higher risk of 1-unit increase in BMI z score (29.0 %, p?=?0.040), 1-cm increase in waist circumference regressed on height and age (3.0 %, p?=?0.027) and 0.1-unit increase in waist/height ratio (21.4 %, p?=?0.031) compared with the “whole milk” cluster. Conclusion: A caloric beverage pattern dominated by intake of “soft drinks” is related to general and abdominal adiposity and diet quality in Spanish male adolescents.  相似文献   
89.
This study compares the lung cancer mortality rates among males in the years 1975–1977 and 1987–1989 in Catalonia and Spain with other European countries selected for their geographical proximity. Adjusted calculations using the direct method have been made for male lung cancer mortality. Adjusted truncated rates for the age groups 0–44, 45–64 and more than 65 years were also calculated, as well as percent differences between the mortality rates of each period studied. Lung cancer mortality rates for males in Catalonia and Spain show relative increments of 46.58% and 52.41%, respectively. In contrast, lung cancer mortality in countries such as England-Wales and Switzerland have decreased. Moreover, the 0–44 year age group in Catalonia and Spain shows the absolute highest rates in the 1987–1989 period among all the countries analyzed. The marked contrast of the lung cancer mortality rate evolution in Catalonia and Spain compared with some other European countries and the considerable increase of the mortality in younger age groups indicate the need to intensify lung cancer control measures. © 1996 Wiley-Liss, Inc.  相似文献   
90.
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