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991.
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Cadmium (Cd), an environmental and dietary contaminant, has been described to mimic the effects of 17β-estradiol (E2) in selected model systems when studied as an inorganic salt. However, inorganic Cd salts do not represent the main form of Cd exposure in general human populations. The aims of this study were to compare the estrogen-like effects and the bioavailability of dietary Cd to inorganic CdCl2. Adult ovariectomized ERE-luc reporter mice were administered two bread based diets containing different concentrations of Cd (17.57 and 49.22 μg/kg, corresponding to oral intakes of 1.8 and 5.1 μg/kg body weight (bw) per day, respectively), inorganic CdCl2 (1 μg/kg bw per day by gavage) or E2 (5 μg/kg bw per day pellet) for 21 days. The effects on estrogen signaling were investigated by studying the uterine weights, luciferase activation, and expression of endogenous estrogen target genes. The uterine weight was significantly increased by both CdCl2 and E2 but not by the Cd containing diets. All treatments modulated the expression of luciferase and the endogenous estrogen target genes; however, there was no consistent overlap between the responses triggered by the bread diets and the responses stimulated by CdCl2 or E2. Oral exposure to Cd was calculated and the concentrations in liver and kidneys quantified to estimate the amount of absorbed Cd retained in tissues. The results suggest significantly lower absorption and/or tissue retention of dietary Cd compared to CdCl2 following oral exposure. Altogether, our results support previous reports on in vivo estrogenicity of CdCl2 but do not suggest the same activity for diet bound Cd. This study calls for caution when extrapolating results from pure compound studies (e.g. estrogenicity of CdCl2) to dietary exposure scenarios (e.g. estrogenicity of diet bound Cd). Further basic research is needed on the mechanisms of interaction between Cd and the estrogen signaling, biologically active species of Cd, and biomarkers of estrogen-like effects of Cd in vivo before human health risk assessment on the hormone disruptive effects of Cd can be carried out.  相似文献   
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Merkel cell carcinoma (MCC) is an aggressive cutaneous tumor with poor outcome and increasing incidence. We examined by immunohistochemistry the expression of three novel matrix metalloproteinases (MMPs)—MMP-21, MMP-26, and MMP-28—in 44 primary MCC tumors and six lymph node metastases while MMP-10 served as a positive control. Their mRNA expression was also studied in the UISO MCC cell line basally and after various stimulations using quantitative real-time PCR. MMP-28 was observed in tumor cells of 15/44 samples especially in tumors <2 cm in diameter (p = 0.015) while 21/44 specimens showed MMP-28 in the tumor stroma. Expression of MMP-21 was demonstrated in tumor cells of 13/43 samples. MMP-26, instead, was positive in stromal cells (17/44) and its expression associated with tumors ≥2 cm in diameter (p = 0.006). Stromal expression of MMP-10 was the most frequent finding of the studied samples (31/44), but MMP-10 was detected also in tumor cells (17/44). Most of the metastatic lymph nodes expressed MMP-10 and MMP-26. MMP-10, MMP-21, and MMP-28 mRNAs were basally expressed by the UISO cells, and the corresponding proteins were detectable by immunostaining of cultured cells. IFN-α and TNF-α downregulated MMP-21 and MMP-28 expression. Our results suggest that novel MMPs may have a role in MCC pathogenesis: especially that MMP-26 expression in stroma is associated with larger tumors with poor prognosis. Expression of MMP-21 and MMP-28 seems to associate with the tumors of lesser malignant potential. We also confirm the previous finding on the role of MMP-10 in MCC pathogenesis.  相似文献   
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Limited data are available on the use of deferiprone in children younger than 10 years of age. This study evaluated the safety and efficacy of a new liquid formulation of deferiprone for the treatment of transfusional iron overload in children 1-10 years old. One hundred children (91 thalassemia major, 8 Hb E-β thalassemia, and 1 sickle cell disease) were enrolled for a 6-month treatment with deferiprone (50 to 100 mg/kg/d). The safety profile was similar to or better than that reported in earlier studies with deferiprone tablets in older children and adults. No unexpected adverse reactions were observed. Gastrointestinal intolerance (GI) was observed in 11% and an increased serum ALT in 12% of the children. Both events were transient. Mild neutropenia, observed in 6% of patients, did not progress to agranulocytosis and resolved despite continuous deferiprone treatment. Two patients experienced agranulocytosis that resolved without complications upon discontinuation of therapy. Deferiprone use was associated with a significant decline in mean serum ferritin level from 2532±1463 μg/L at baseline to 2176±1144 μg/L (P<0.0005). The results of this study show a favorable benefit/risk ratio of deferiprone oral solution for the treatment of young children with transfusional iron overload.  相似文献   
999.
Of the Finnish persons aged 85 years or older, living at home, 555 (67% of this age class) were monitored for two years to describe the circumstances and the frequency of falls and injury-causing falls. The incidence rates of falls, major soft tissue injuries and fractures were 1039 (95% confidence interval = CI: 974-1093), 74 (58-92) and 89 (72-108), respectively. The incidence of falls was higher among women 1127 (1055-1199) than among men 755 (651-870), but only among those younger than 90 years. The probability of getting injured in a fall was higher in the morning (p = 0.010) and in the evening (p = 0.007) as compared to the daytime. More injury-causing falls than other falls were non-defined as regards ongoing activity at the time of fall (p < 0.001) and type of falling (p < 0.001). Ongoing activity and type of falling did not discriminate injury-causing falls from other falls after exclusion of the non-defined falls. We conclude that incidence of falls among the home-dwelling elderly increases up to the oldest ages, especially among the men. Time of day affects the occurrence of injuries in falls. Ongoing activity and type of falling play a minor role in falls causing injuries among the most elderly.  相似文献   
1000.
BACKGROUND AND METHODS: We aimed to assess whether fasting plasma triglycerides independently predicted future fatal and nonfatal cardiovascular disease (CVD) in a population having a high prevalence of the metabolic syndrome. In the Turkish Adult Risk Factor Study, a population-based survey, 2682 men and women 20 years of age or over with fasting triglyceride values available and free of CVD at baseline examination in 1990, were prospectively followed up till 2003/04. Triglyceride concentrations were measured by the enzymatic dry chemistry method and stratified into sex-specific quintiles. Information on the mode of death was obtained from first-degree relatives and/or health personnel of local health office. Diagnosis of coronary heart disease and stroke among survivors was based on history, physical examination of the cardiovascular system and Minnesota coding of resting electrocardiograms. A total of 120 fatal and 221 new nonfatal CVD occurred among adults (mean age 43+/-14) during a mean 9.3 years of follow-up. RESULTS: CVD was significantly and independently predicted by the top versus the bottom fasting triglyceride quintile in logistic regression analyses when adjusted for age, sex, BMI, systolic blood pressure, total cholesterol, lipid-lowering medication, status of smoking and of glucose regulation (relative risk [RR] in men and all adults 2.38 and 1.79, respectively, p both <0.02). This corresponded to hazard ratios (HR) of 1.43 in men and 1.28 in men and women combined. Adjustment for HDL-cholesterol instead of total cholesterol in the same model gave also significant HRs corresponding to 1.42 in men and 1.32 in sexes combined. CONCLUSIONS: Fasting triglycerides are predictive of future CVD among men with an HR of 1.4, independent of age, diabetes, lipid-lowering medication, traditional risk factors including total cholesterol or HDL-C, in a population in which metabolic syndrome prevails. A modest independent risk increment in women did not reach significance.  相似文献   
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