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Background We investigated whether associations between prevalent diabetes and cancer risk are pertinent to older adults and whether associations differ across subgroups of age, body weight status or levels of physical activity.Methods We harmonised data from seven prospective cohort studies of older individuals in Europe and the United States participating in the CHANCES consortium. Cox proportional hazard regression was used to estimate the associations of prevalent diabetes with cancer risk (all cancers combined, and for colorectum, prostate and breast). We calculated summary risk estimates across cohorts using pooled analysis and random-effects meta-analysis.Results A total of 667,916 individuals were included with an overall median (P25–P75) age at recruitment of 62.3 (57–67) years. During a median follow-up time of 10.5 years, 114,404 total cancer cases were ascertained. Diabetes was not associated with the risk of all cancers combined (hazard ratio (HR) = 0.94; 95% confidence interval (CI): 0.86–1.04; I2 = 63.3%). Diabetes was positively associated with colorectal cancer risk in men (HR = 1.17; 95% CI: 1.08–1.26; I2 = 0%) and a similar HR in women (1.13; 95% CI: 0.82–1.56; I2 = 46%), but with a confidence interval including the null. Diabetes was inversely associated with prostate cancer risk (HR = 0.81; 95% CI: 0.77–0.85; I2 = 0%), but not with postmenopausal breast cancer (HR = 0.96; 95% CI: 0.89–1.03; I2 = 0%). In exploratory subgroup analyses, diabetes was inversely associated with prostate cancer risk only in men with overweight or obesity.Conclusions Prevalent diabetes was positively associated with colorectal cancer risk and inversely associated with prostate cancer risk in older Europeans and Americans.Subject terms: Risk factors, Cancer epidemiology  相似文献   
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Objectives

This study aims to evaluate periodontal microbiological differences between systemically healthy nonsmoker males taking anabolic androgenic steroids (AASs) and non-AAS users and to find associations between disease severity and AAS use.

Methods

Ninety-two men practicing bodybuilding were included in the study. They were divided into AAS users and a matched control nonuser group and subgrouped based on their most severe periodontal condition. Pooled subgingival samples from each individual were cultured to evaluate specific periodontopathogen infection.

Results

AAS users had significantly higher prevalence of severe periodontitis. AAS users had greater gingival inflammation and clinical attachment loss of ≥3 mm than nonusers (odds ratio (OR)?=?2.4; p?=?0.09; 95 % confidence interval (CI) 0.8–6.4). AAS users were 4.9 times more likely to be infected with Prevotella intermedia than AAS nonusers (OR?=?4.9; p?=?0.003; 95 % CI 1.6–14.7). The OR of presenting subgingival Aggregatibacter actinomycetemcomitans was 8.2 times higher in AAS users (OR?=?8.2; p?=?0.03; 95 % CI 0.9–70.8). AAS users were 5.6 times more likely to present subgingival Candida spp. than nonusers (OR?=?5.6; p?=?0.02; 95 % CI 1.1–27.1). AAS users were 14.8 times more likely to present subgingival Candida parapsilosis than nonusers (OR?=?14.8; p?<?0.0001; 95 % CI 3.1–69.2). The likelihood of AAS users presenting subgingival Candida tropicalis was 4.3 times higher than nonusers (OR?=?4.3; p?=?0.03; 95 % CI 1.1–16.9). A. actinomycetemcomitans was mostly isolated in individuals with severe periodontitis and was associated with subgingival Porphyromonas gingivalis, P. intermedia, and Candida spp.

Conclusions

AAS use may increase the risk for severe periodontitis and may cause a subgingival selection of certain Candida species. Specific periodontopathogens, such as Candida dubliniensis and Candida albicans, seem to be negatively affected by AAS use. The higher risk for disease progression in AAS users may be explained by the significantly higher proportions of A. actinomycetemcomitans, P. gingivalis, P. intermedia, and Candida species as compared to controls.

Clinical significance

Data on the influence of AAS on subgingival periodontopathogens and disease progression are scarce. Higher proportions of specific periodontopathogens are plausible in AAS users. AAS users had a higher prevalence of severe periodontitis, gingival inflammation, and clinical attachment loss. Men taking AAS are at greater risk of periodontitis and specific periodontopathogen infection.  相似文献   
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Background

The high variation in responses to bariatric surgery might be partially explained by genetic effects. Recently, common polymorphisms of the fat mass and obesity-associated gene (FTO) have been linked to obesity in some populations. Only two studies have investigated the effect of FTO variants on weight loss of morbid obese patients undergoing bariatric surgery with contradictory results.

Objective

We decided to investigate the role of the rs9939609 FTO gene polymorphism on outcomes after a biliopancreatic diversion surgery (BPD) in morbidly obese patients.

Design

A sample of 119 morbidly obese patients' body mass index (BMI)?>?40?kg/m2 were operated. Weight, fat mass, blood pressure, basal glucose, triacylglycerols, total cholesterol, low density lipoprotein cholesterol and high density lipoprotein cholesterol were measured at basal visit and at each visit (basal, 3, 9 and 12?months). The frequency of metabolic comorbidities was recorded at each visit.

Results

Thirty-seven patients (31.1%) had genotype TT (wild type group), 58 (48.7%) patients had genotype TA and 24 patients (20.2%) had genotype AA. In the wild and mutant type groups, BMI, weight, waist circumference, systolic blood pressure and diastolic blood pressure decreased in a significant way. In the wild type groups, glucose, total cholesterol, low density lipoprotein (LDL) cholesterol and triacylglycerol concentrations decreased at 3, 9 and 12?months after surgery. In the mutant type groups, glucose, total cholesterol and triacylglycerol concentrations decreased at 3, 9 and 12?months after surgery. LDL cholesterol decreased at 9 and 12?months after surgery. Initial weight percent loss at 3?months of follow-up was higher in the wild type group (26.1% vs. 18.6%: p?Conclusion Our study showed a higher initial weight loss at 3?months after the TT variant of FTO gene (rs9939609). However, the weight loss at 9 and 12?months of BPD was similar in both genotypes with a significant improvement in biochemical parameters and cardiovascular comorbidities.  相似文献   
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Nanotechnology is expected to contribute to the protection of the environment, but many uncertainties exist regarding the environmental and human implications of manufactured nanomaterials (MNMs). Contradictory results have been reported for their ecotoxicity to aquatic organisms, which constitute one of the most important pathways for their entrance and transfer throughout the food web. The present review is focused on the international strategies that are laying the foundations of the ecotoxicological assessment of MNMs. Specific advice is provided on the preparation of MNM dispersions in the culture media of the organisms, which is considered a key factor to overcome the limitations in the standardization of the test methodologies.  相似文献   
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OBJECTIVE: The aim of our study was to examine, in a prospective way, whether any nutritional parameter could predict outcomes after liver transplantation. MATERIAL AND SUBJECTS: A nutritional assessment was performed in 31 consecutive patients six months prior to undergoing orthotopic liver transplantation (OLT) at a single center (Hospital U. Río Hortega) and after six months of OLT (December 2002-June 2004). The nutritional evaluation included Subjective Global Assessment (SGA), Mini Nutritional Assessment test (MNA), anthropometry, laboratory tests, and three-day diet diary completed. The body composition analysis was performed by tetrapolar body electrical bioimpedance and skin folds in a standard way. RESULTS: Our patients had an average age of 56.2 +/- 8.11 years; weight was 72.9 +/- 15.3 kg, and body mass index was 26.6 +/- 4.1. The anthropometric evaluation showed the following data: tricipital skin fold 12.2 +/- 6.1 mm, mid-arm circumference 24.5 +/- 4.1 cm, fat-free mass 54.5 +/- 10.9 kg, fat mass 18.4 +/- 6.5 mm, and body water 41.4 +/- 9.1 kg. After six months from liver transplantation, these parameters remained unchanged. Energy intake, as corrected by weight, was similar pre- and post-liver transplantation (28.1 +/- 6 kcal/kg vs. 27.5 +/- 5.8 kcal/kg: ns). Albumin, prealbumin and transferrin improved after 6 months from transplantation. Length of stay in hospital was 22.4 +/- 14.9 days, and length of stay in ICU was 0.7 +/- 1.7 days. The nutritional status (SGA and MNA tests) of patients did not influence length of stay in either hospital or ICU. No intercurrent events (infections: urinary tract infection, pneumonia, and peritonitis) were recorded during the 6-month study period. Two patients died after liver transplantation (6.5%), and 3 patients had acute rejection (9.6%). Patients with malnutrition (SGA and MNA tests classification) showed no differences in rejection and mortality. CONCLUSIONS: Our liver transplantation population had normal nutritional status and dietary intake. Nutritional parameters showed no association with outcomes after liver transplantation. Liver transplantation improved serum protein levels and did not modify weight or dietary intake. Further studies are needed to clarify the role of liver transplantation on nutritional status and of nutritional status on liver transplantation outcomes, considering different populations of patients.  相似文献   
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