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891.
Lundin E Wirgin I Lukanova A Afanasyeva Y Krogh V Axelsson T Hemminki K Clendenen TV Arslan AA Ohlson N Sieri S Roy N Koenig KL Idahl A Berrino F Toniolo P Hallmans G Försti A Muti P Lenner P Shore RE Zeleniuch-Jacquotte A 《Cancer epidemiology》2012,36(5):445-452
Background: The role of estrogen and progesterone in the development of endometrial cancer is well documented. Few studies have examined the association of genetic variants in sex hormone-related genes with endometrial cancer risk. Methods: We conducted a case-control study nested within three cohorts to examine the association of endometrial cancer risk with polymorphisms in hormone-related genes among 391 cases (92% postmenopausal at diagnosis) and 712 individually-matched controls. We also examined the association of these polymorphisms with circulating levels of sex hormones and SHBG in a cross-sectional analysis including 596 healthy postmenopausal women at blood donation (controls from this nested case-control study and from a nested case-control study of breast cancer in one of the three cohorts). Results: Adjusting for endometrial cancer risk factors, the A allele of rs4775936 in CYP19 was significantly associated (OR(per allele)=1.22, 95% CI=1.01-1.47, p(trend)=0.04), while the T allele of rs10046 was marginally associated with increased risk of endometrial cancer (OR(per allele)=1.20, 95% CI=0.99-1.45, p(trend)=0.06). PGR rs1042838 was also marginally associated with risk (OR(per allele)=1.25, 95% CI=0.96-1.61, p(trend)=0.09). No significant association was found for the other polymorphisms, i.e. CYP1B1 rs1800440 and rs1056836, UGT1A1 rs8175347, SHBG rs6259 and ESR1 rs2234693. Rs8175347 was significantly associated with postmenopausal levels of estradiol, free estradiol and estrone and rs6259 with SHBG and estradiol. Conclusion: Our findings support an association between genetic variants in CYP19, and possibly PGR, and risk of endometrial cancer. 相似文献
892.
KN Burger JW Beulens YT van der Schouw I Sluijs AM Spijkerman D Sluik H Boeing R Kaaks B Teucher C Dethlefsen K Overvad A Tjønneland C Kyrø A Barricarte B Bendinelli V Krogh R Tumino C Sacerdote A Mattiello PM Nilsson M Orho-Melander O Rolandsson JM Huerta F Crowe N Allen U Nöthlings 《PloS one》2012,7(8):e43127
Background
Dietary fiber, carbohydrate quality and quantity are associated with mortality risk in the general population. Whether this is also the case among diabetes patients is unknown.Objective
To assess the associations of dietary fiber, glycemic load, glycemic index, carbohydrate, sugar, and starch intake with mortality risk in individuals with diabetes.Methods
This study was a prospective cohort study among 6,192 individuals with confirmed diabetes mellitus (mean age of 57.4 years, and median diabetes duration of 4.4 years at baseline) from the European Prospective Investigation into Cancer and Nutrition (EPIC). Dietary intake was assessed at baseline (1992–2000) with validated dietary questionnaires. Cox proportional hazards analysis was performed to estimate hazard ratios (HRs) for all-cause and cardiovascular mortality, while adjusting for CVD-related, diabetes-related, and nutritional factors.Results
During a median follow-up of 9.2 y, 791 deaths were recorded, 306 due to CVD. Dietary fiber was inversely associated with all-cause mortality risk (adjusted HR per SD increase, 0.83 [95% CI, 0.75–0.91]) and CVD mortality risk (0.76[0.64–0.89]). No significant associations were observed for glycemic load, glycemic index, carbohydrate, sugar, or starch. Glycemic load (1.42[1.07–1.88]), carbohydrate (1.67[1.18–2.37]) and sugar intake (1.53[1.12–2.09]) were associated with an increased total mortality risk among normal weight individuals (BMI≤25 kg/m2; 22% of study population) but not among overweight individuals (P interaction≤0.04). These associations became stronger after exclusion of energy misreporters.Conclusions
High fiber intake was associated with a decreased mortality risk. High glycemic load, carbohydrate and sugar intake were associated with an increased mortality risk in normal weight individuals with diabetes. 相似文献893.
Gremigni V 《The International journal of developmental biology》2012,56(1-3):49-52
Vittorio Gremigni is a scientific leader in the field of planarian biology with a very long historical perspective. By using electron microscopy, he contributed to the reconstruction of the phylogenesis of free living "Turbellaria", and he pioneered the study of the origin of blastema cells by using chromosomal markers. In this interview, Professor Gremigni describes the steps that moved his career towards the planarian field, the main scientific achievements he obtained and the changes that are taking place in the field. He also discusses recent progress and unanswered questions on planarian neoblasts and regeneration. 相似文献
894.
VacA toxin from the cancer-inducing bacterium Helicobacter pylori is currently classified as a pore-forming toxin but is also considered a multifunctional toxin, apparently causing many pleiotropic cell effects. However, an increasing body of evidence suggests that VacA could be the prototype of a new class of monofunctional A-B toxins in which the A subunit exhibits pore-forming instead of enzymatic activity. Thus, VacA may use a peculiar mechanism of action, allowing it to intoxicate the human stomach. By combining the action of a cell-binding domain, a specific intracellular trafficking pathway and a novel mitochondrion-targeting sequence, the VacA pore-forming domain is selectively delivered to the inner mitochondrial membrane to efficiently kill target epithelial cells by apoptosis. 相似文献
895.
Angus Thompson Thomas Schroeder Vittorio E. Brando Britta Schaffelke 《Coral reefs (Online)》2014,33(4):923-938
A five-year period (2002–2006) of below-median rainfall followed by a six-year period (2007–2012) of above-median rainfall and seasonal flooding allowed a natural experiment into the effects of runoff on the water quality and subsequent coral community responses in the Whitsunday Islands, Great Barrier Reef (Australia). Satellite-derived water quality estimates of total suspended solids (TSS) and chlorophyll-a (Chl) concentration showed marked seasonal variability that was exaggerated during years with high river discharge. During above-median rainfall years, Chl was aseasonally high for a period of 3 months during the wet season (February–April), while TSS was elevated for four months, extending into the dry season (March–June). Coinciding with these extremes in water quality was a reduction in the abundance and shift in the community composition, of juvenile corals. The incidence of coral disease was at a maximum during the transition from years of below-median to years of above-median river discharge. In contrast to juvenile corals, the cover of larger corals remained stable, although the composition of communities varied along environmental gradients. In combination, these results suggest opportunistic recruitment of corals during periods of relatively low environmental stress with selection for more tolerant species occurring during periods of environmental extremes. 相似文献
896.
897.
898.
899.
Edoardo Alessandro Pulixi Eleonora Tobaldini Pier Maria Battezzati Paola D'Ingianna Vittorio Borroni Anna Ludovica Fracanzani Marco Maggioni Serena Pelusi Mara Bulgheroni Massimo Zuin Silvia Fargion Nicola Montano Luca Valenti 《PloS one》2014,9(4)
Background
A high prevalence of obstructive sleep apnea syndrome (OSAS) has been reported in severely obese patients with nonalcoholic fatty liver disease (NAFLD), but few studies have evaluated OSAS in non-morbidly obese NAFLD patients.Aims
To determine the prevalence of risk for OSAS with or without daytime sleepiness in non-morbidly obese patients with NAFLD and evaluate the association with the severity of liver damage.Methods
We considered 159 consecutive patients with histological NAFLD and body mass index (BMI) <35 Kg/m2, and 80 controls without ultrasonographic steatosis matched for age, sex, and BMI. OSAS risk was determined by positivity for Berlin questionnaire (BQ), and daytime sleepiness by the Sleepness Epworth Scale (ESS). Liver damage was evaluated according to the NAFLD activity score.Results
In NAFLD patients, BQ alone was positive in 39 (25%), ESS in 8 (5%), and both in 13 (8%, OSAS with sleepines); p = ns vs. controls without steatosis. In NAFLD patients at risk for OSAS with (but not in those without) sleepiness, we observed a higher prevalence of nonalcoholic steatohepatitis (NASH; 11/13, 85% vs. 72/146, 49%; p = 0.018), and of clinically significant fibrosis (stage>1; 9/13, 69% vs. 39/146, 27%; p = 0.003). At multivariate logistic regression analysis, OSAS with sleepiness was strongly associated with NASH and fibrosis>1 independently of known clinical risk factors such as age, gender, BMI, diabetes, and ALT levels (OR 7.1, 95% c.i. 1.7–51, p = 0.005 and OR 14.0, 95% c.i. 3.5–70, p = 0.0002, respectively).Conclusions
A proportion of NAFLD patients without severe obesity is at risk for OSAS with daytime sleepiness, which is associated with the severity of liver damage independently of body mass and other cofactors. 相似文献900.
Jens Durruthy-Durruthy Sharon F. Briggs Jason Awe Cyril Y. Ramathal Saravanan Karumbayaram Patrick C. Lee Julia D. Heidmann Amander Clark Ioannis Karakikes Kyle M. Loh Joseph C. Wu Andrew R. Hoffman James Byrne Renee A. Reijo Pera Vittorio Sebastiano 《PloS one》2014,9(4)
Data suggest that clinical applications of human induced pluripotent stem cells (hiPSCs) will be realized. Nonetheless, clinical applications will require hiPSCs that are free of exogenous DNA and that can be manufactured through Good Manufacturing Practice (GMP). Optimally, derivation of hiPSCs should be rapid and efficient in order to minimize manipulations, reduce potential for accumulation of mutations and minimize financial costs. Previous studies reported the use of modified synthetic mRNAs to reprogram fibroblasts to a pluripotent state. Here, we provide an optimized, fully chemically defined and feeder-free protocol for the derivation of hiPSCs using synthetic mRNAs. The protocol results in derivation of fully reprogrammed hiPSC lines from adult dermal fibroblasts in less than two weeks. The hiPSC lines were successfully tested for their identity, purity, stability and safety at a GMP facility and cryopreserved. To our knowledge, as a proof of principle, these are the first integration-free iPSCs lines that were reproducibly generated through synthetic mRNA reprogramming that could be putatively used for clinical purposes. 相似文献