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291.
Sara Grioni Claudia Agnoli Sabina Sieri Valeria Pala Fulvio Ricceri Giovanna Masala Calogero Saieva Salvatore Panico Amalia Mattiello Paolo Chiodini Rosario Tumino Graziella Frasca Licia Iacoviello Amalia de Curtis Paolo Vineis Vittorio Krogh 《PloS one》2015,10(5)
Background
The relationship between coffee consumption and coronary heart disease (CHD) has been investigated in several studies with discrepant results. We examined the association between Italian-style (espresso and mocha) coffee consumption and CHD risk.Methods
We investigated 12,800 men and 30,449 women without history of cardiovascular disease recruited to the EPICOR prospective cohort study. Coffee consumption was assessed at baseline. In a random sub-cohort of 1472 subjects, plasma triglycerides, and total, LDL and HDL cholesterol were determined to investigate the effect of coffee consumption on plasma lipids.Results
After a mean follow up of 10.9 years, 804 cases of CHD (500 acute events, 56 fatal events and 248 revascularizations, all first events) were identified. Multivariable adjusted hazard ratios for CHD were: 1.18 (95% CI 0.87–1.60) for drinking 1–2 cups/day, 1.37 (95% CI 1.03–1.82) for >2–4 cups/day and 1.52 (95% CI 1.11–2.07) for over 4 cups/day (P trend <0.001) compared to reference (<1 cup/day). Plasma triglycerides, and total, LDL and HDL cholesterol did not vary significantly (ANOVA) with coffee consumption.Conclusion
Consumption of over 2 cups/day of Italian-style coffee is associated with increased CHD risk, but coffee consumption was not associated with plasma lipid changes, so the adverse effect of consumption appears unrelated to lipid profile. 相似文献292.
Background
Pentoxifylline (PTX) is a promising therapeutic approach for reducing inflammation and improving anemia associated to various systemic disorders. However, whether this agent may be helpful for anemia management also in CKD patients is still object of debate.Study Design
Systematic review and meta-analysis.Population
Adults with CKD (any KDOQI stage, including ESKD patients on regular dialysis) and anemia (Hb<13 g/dL in men or < 12 g/dL in women).Search Strategy and Sources
Cochrane CENTRAL, EMBASE, Ovid-MEDLINE and PubMed were searched for studies providing data on the effects of PTX on anemia parameters in CKD patients without design or follow-up restriction.Intervention
PTX derivatives at any dose regimen.Outcomes
Hemoglobin, hematocrit, ESAs dosage and resistance (ERI), iron indexes (ferritin, serum iron, TIBC, transferrin and serum hepcidin) and adverse events.Results
We retrieved 11 studies (377 patients) including seven randomized controlled trials (all comparing PTX to placebo or standard therapy) one retrospective case-control study and three prospective uncontrolled studies. Overall, PTX increased hemoglobin in three uncontrolled studies but such improvement was not confirmed in a meta-analysis of seven studies (299 patients) (MD 0.12 g/dL, 95% CI -0.22 to 0.47). Similarly, there were no conclusive effects of PTX on hematocrit, ESAs dose, ferritin and TSAT in pooled analyses. Data on serum iron, ERI, TIBC and hepcidin were based on single studies. No evidence of increased rate of adverse events was also noticed.Limitations
Small sample size and limited number of studies. High heterogeneity among studies with respect to CKD and anemia severity, duration of intervention and responsiveness/current therapy with iron or ESAs.Conclusions
There is currently no conclusive evidence supporting the utility of pentoxifylline for improving anemia control in CKD patients. Future trials designed on hard, patient-centered outcomes with larger sample size and longer follow-up are advocated. 相似文献293.
294.
Graziella Mura 《International Review of Hydrobiology》2005,90(3):277-291
The pattern of cyst distribution in the absence of turbation and their hatching behaviour were studied in an outdoor artificial pool, where just differentiated adults of the anostracan Chirocephalus ruffoi (sex ratio 1:3) lived until it dried up. The horizontal and vertical distributions of cysts in the pool bed were determined. The comparison between cyst bank estimate (Mura , 2004) and the actual number of cysts counted in the pool bed revealed an estimate error of 20.9%. Resting eggs occurred only in the upper 2.5 cm thick soil sections and decreased within this section as depth increased. Peripheral areas of the pool contained significantly larger numbers of cysts than the central area. Multiway analysis on the results recorded in hatching success (nested ANOVA) revealed that the differences were significantly affected by initial soil conditions, treatment and vertical distribution of cysts. Among these factors, vertical distribution (sections nested in cores) was the most influential. Hatching success was significantly inversely related to depth. Differences in the timing of hatching depending on the above considered factors were also noted. A nearly synchronous hatching pattern was observed only for cysts from initially dry sediment of the uppermost layers. In all successively deeper layers, hatching showed multiple peaks and was increasingly delayed and erratic (already mentioned). ANCOVA within each of the experimental conditions revealed significant differences in hatching frequencies (time as covariate) depending on sediment depth. Within any given layer, ANCOVA revealed a significant influence of initial sediment conditions and treatment on the timing of hatching. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
295.
Tim Smilda Dick A. Lamme Graziella Collu Peter A. Jekel Peter Reinders Jaap J. Beintema 《Biochemical genetics》1998,36(1-2):15-36
The enzyme alcohol dehydrogenase (ADH) fromseveral naturally occurring ADH variants ofDrosophila melanogaster and Drosophilasimulans was isolated. Affinity chromatography withthe ligand Cibacron Blue and elution with NAD+ showed similarbehavior for D. melanogaster ADH-FF, ADH-71k,and D. simulans ADH. Introduction of a secondCibacron Blue affinity chromatography step, withgradient elution with NAD+, resulted in pure and stable enzymes. D.melanogaster ADH-SS cannot be eluted from theaffinity chromatography column at a high concentrationof NAD+ and required a pH gradient for itspurification, preceded by a wash step with a high concentration ofNAD+. Hybrid Drosophila melanogasteralcohol dehydrogenase FS has been isolated fromheterozygous flies, using affinity chromatography withfirst elution at a high concentration NAD+, directlyfollowed by affinity chromatography elution with a pHgradient. Incubation of equal amounts of pure homodimersof Drosophila melanogaster ADH-FF and ADH-SS,in the presence of 3 M urea at pH 8.6, for 30 min at roomtemperature, followed by reassociation yielded activeDrosophila melanogaster ADH-FS heterodimers. Noproteolytic degradation was found after incubation ofpurified enzyme preparations in the absence or presenceof SDS, except for some degradation of ADH-SS after verylong incubation times. The thermostabilities of D.melanogaster ADH-71k and ADH-SS were almostidentical and were higher than those of D.melanogaster ADH-FF and D. simulans ADH. Thethermostability of D. melanogaster ADH-FS waslower than those of D. melanogaster ADH-FF andADH-SS. D. melanogaster ADH-FF and ADH-71k have identical inhibition constantswith the ligand Cibacron Blue at pH 8.6, which are twotimes higher at pH 9.5. The Ki values forD. simulans ADH are three times lower at bothpH values. D. melanogaster ADH-SS and ADH-FS havesimilar Ki values, which are lower than thosefor D. melanogaster ADH-FF at pH 8.6. But at pH9.5 the Ki value for ADH-FS is the same as atpH 8.6, while that of ADH-SS is seven times higher. Kinetic parameters ofDrosophila melanogaster ADH-FF, ADH-SS, andADH-71k and Drosophila simulans ADH, at pH 8.6and 9.5, showed little or no variation inKm
eth values. TheKm
NAD values measured at pH 9.5for Drosophila alcohol dehydrogenases are alllower than those measured at pH 8.6. The rate constants(kcat) determined for all fourDrosophila alcohol dehydrogenases are higher at pH 9.5 than at pH 8.6. D.melanogaster ADH-FS showed nonlinear kinetics. 相似文献
296.
297.
298.
299.
Paola Astolfi Graziella Caselli Ornella Fiorani Rosa M. Lipsi Antonella Lisa Stefania Tentoni 《Evolution and human behavior》2009,30(2):93-102
Evolution in human life-history traits is influenced by environmental factors and, when genetic components underlie the relations, by micro-evolutionary forces. Age at reproduction is largely influenced by the familial cultural context and socioeconomic level, besides the maternal well-being and genetic background. The Sardinian population is characterized by historico-geographical isolation and differentiates from Italian mainland and other European populations in bio-demographic and cultural characteristics, among which the tendency to delay maternity persisting through generations. In our study, we investigated whether, in Sardinia, areas of “reproductive longevity” exist, where a higher-than-average incidence of late maternities combines with a lower-than-average cost in terms of perinatal death. Data from the Italian Central Institute of Statistics regard all 1980–1996 Sardinian births. Using spatial analysis of late maternity (proportion of babies born to mothers aged ≥35 years) and associated perinatal mortality (proportion of babies stillborn and dead within 0–6 days born to mothers aged ≥35 years), we aimed at singling out areas where the indicators run high and low, respectively. The perinatal mortality cost associated with the advanced maternal age [odds ratios (95% CI)] was evaluated through multiple logistic regression models. We identified central inland excess areas qualified by higher incidence of late maternities (27% vs. 22% in nonexcess area) and lower cost in perinatal mortality [OR=1.38 (1.04–1.84) vs. OR=1.74 (1.55–1.96) in nonexcess area]. In these “reproductive longevity” areas, the inbreeding coefficient was 3.7-fold higher than in the nonexcess areas, suggesting possible population homozygosity in genetic factors affecting the trait. Further and deeper investigations on biological and environmental determinants could focus on these target areas. 相似文献
300.