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Long-term exposures to organotin compounds have shown alterations on endogenous steroid levels in gastropods together with the development of imposex. However, information regarding short-term effects of these compounds on the endocrine system of gastropods is lacking. This work aimed at investigating those responses in the ramshorn snail Marisa cornuarietis by looking at both endogenous levels of free and esterified steroids and the metabolism of the androgen precursor androstenedione by digestive gland/gonad microsomal fractions. One-week exposure to the organotin compound triphenyltin (TPT) led to a significant increase in esterified testosterone (60-85%) and a decrease in esterified estradiol (50-84%) in females, but had no effect on males. The observed alterations in esterified steroids were not directly related to changes in P450 aromatase activity that remained unchanged in exposed females. The enzymes involved in the metabolism of the androgen precursor androstenedione, namely 17beta-hydroxysteroid dehydrogenases and 5alpha-reductases, were not significantly altered by TPT exposure, suggesting that such enzymes are not primary targets of TPT in M. cornuarietis. Additional studies are needed to fully understand the significance of the observed alterations in females and their potential relationship with the development of imposex.  相似文献   
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Previous studies with mast cell degranulating (MCD) peptide have shown that peptide [Ala(12)]MCD 8 was an inhibitor of IgE binding to mast cell receptors. In an attempt to produce increased inhibition, analogs were synthesized that maintained the alanine residue in position 12 in the MCD peptide sequence and were further modified at both termini. Analogs modified at the C-terminus were [Ala(12),desLys(21)]MCD 2 and [Ala(12),D-Lys(21)]MCD 4. N-terminus modifications were [desLys(6)-Arg(7)-His(8),Ala(12)]MCD 1, [Ala(6), Ala(12)]MCD 6, and [Val(6),Ala(12)]MCD 7. To assess the role of the Proline(12), analogs [D-Ala(12)]MCD 3 and [Meleu(12)]MCD 5 were also synthesized. The analogs were tested for binding to the IgE receptor in cultured mast cells. Inhibitory activity of IgE-caused degranulation was measured using a beta-hexosaminidase assay. Circular dichroism (CD) and molecular modeling of selected analogs were used to follow possible structural differences among these analogs. All analogs showed binding affinity to the IgE receptor and inhibition of IgE-induced mast cell degranulation at different levels. Differences in inhibition were most likely because of diverse interactions of the analogs with the receptor as inferred by the CD and modeling studies. Based on the results of the beta-hexosaminidase assay, analog [Val(6), Ala(12)]MCD 7 proved to be an excellent inhibitor of IgE-mediated mast cell degranulation.  相似文献   
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Perforation of the clavicle by supraclavicular nerves is a common anatomical variation. This variation has been reported in several studies based on post-mortem, surgical and radiologic findings, with an overall frequency between 1 and 6.6 %. The penetrating branch passes either through a bony tunnel or a groove on the superior surface of the bone. Entrapment neuropathy of the perforating branch is a documented clinical entity reported in the literature. The intraosseous course of the supraclavicular nerves makes them vulnerable to injury in case of clavicular fractures or during surgical manipulations of these fractures. Furthermore, this variation should be taken into account during the interpretation of chest and shoulder radiographs. The purpose of the current study is to perform an extended review of the relevant literature, highlighting the clinical impact of this variation, as well as to incorporate our own findings into them.  相似文献   
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Uterine serous carcinoma accounts for 3–10% of endometrial cancers, but it is the most lethal histopathological subtype. The molecular characterization of endometrial carcinomas has allowed novel therapeutic approaches for these patients. We undertook a retrospective analysis of patients with uterine serous carcinomas treated in our hospital within the last two decades to identify possible changes in their management. The patients and their characteristics were evenly distributed across the two decades. Treatment modalities did not change significantly throughout this period. After adjuvant treatment, patients’ median disease-free survival was 42.07 months (95% CI: 20.28–63.85), and it did not differ significantly between the two decades (p = 0.059). The median overall survival was 47.51 months (95% Cl: 32.18–62.83), and it significantly favored the first decade’s patients (p = 0.024). In patients with de novo metastatic or recurrent disease, median progression-free survival was 7.8 months (95% Cl: 5.81–9.93), whereas both the median progression-free survival and the median overall survival of these patients did not show any significant improvement during the examined time period. Overall, the results of our study explore the minor changes in respect of uterine serous carcinoma’s treatment over the last two decades, which are reflected in the survival outcomes of these patients and consequently underline the critical need for therapeutic advances in the near future.  相似文献   
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While the contributing factors leading to endometriosis remain unclear, its clinical heterogeneity suggests a multifactorial causal background. Amongst others, caffeine has been studied extensively during the last decade as a putative contributing factor. In this systematic review and meta-analysis, we provide an overview/critical appraisal of studies that report on the association between caffeine consumption and the presence of endometriosis. In our search strategy, we screened PubMed and Scopus for human studies examining the above association. The main outcome was the relative risk of endometriosis in caffeine users versus women consuming little or no caffeine (<100 mg/day). Subgroup analyses were conducted for different levels of caffeine intake: high (>300 mg/day) or moderate (100–300 mg/day). Ten studies were included in the meta-analysis (five cohort and five case-control studies). No statistically significant association was observed between overall caffeine consumption and risk for endometriosis (RR 1.12, 95% confidence interval (CI) 0.97–1.28, I2 = 70%) when compared to little or no (<100 mg/day) caffeine intake. When stratified according to level of consumption, high intake was associated with increased risk of endometriosis (RR 1.30, 95%CI 1.04–1.63, I2 = 56%), whereas moderate intake did not reach nominal statistical significance (RR 1.18, 95%CI 0.99–1.40, I2 = 37%). In conclusion, caffeine consumption does not appear to be associated with increased risk for endometriosis. However, further research is needed to elucidate the potential dose-dependent link between caffeine and endometriosis or the probable role of caffeine intake as a measurement of other unidentified biases.  相似文献   
108.
ObjectivesTo assess secular changes in physical fitness (PF), moderate-to-vigorous-physical activity (MVPA) and TV-viewing in 1st-grade children from Crete, Greece.DesignCross-sectional cohorts examined in academic years 1992/93 and 2006/07.MethodsTwo representative samples of children, aged 5.9–7.8 years, were studied during 1992/93 (N = 606) and 2006/07 (N = 361). PF (sit-and-reach, standing-broad-jump, sit-ups and 20 m-shuttle-run-test) was assessed by the European-PF test battery and MVPA by a physical activity (PA) questionnaire. Data on the frequency of TV-viewing was also collected.ResultsBetween 1992/93 and 2006/07, there was a significant increase in all fitness tests in both genders (P < 0.001) and in MVPA in boys (76.5 min/week vs. 38.7 min/week, P < 0.001). Time spent watching TV on weekdays was significantly more in both genders in 2006/07, compared to 1992/93 (P < 0.001). In 2006/07, active boys and active girls spent more time in MVPA than active boys and girls in 1992/93 (P < 0.001). Significantly higher proportions of boys and girls engaged in vigorous activities in 2006/07, than 1992/93 (P < 0.001 and P = 0.027, respectively).ConclusionsA significant increase in physical and cardiorespiratory fitness in both genders and MVPA in boys was observed in children from Crete between 1992/93 and 2006/07. The increase in weekday TV-viewing, despite being parallel to an increase in leisure-time MVPA, could have an unfavorable effect on health and should be tackled in future interventions in this population. Dietary, anthropometric and biochemical indices should also be investigated to assess their impact on the secular changes in physical fitness and activity observed in this sample of children.  相似文献   
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