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991.
Context: Non-nutritive sweeteners can bind to sweet-taste receptors present not only in the oral cavity, but also on enteroendocrine and pancreatic islet cells. Thus, these sweeteners may have biological activity by eliciting or inhibiting hormone secretion. Because consumption of non-nutritive sweeteners is common in the United States, understanding the physiological effects of these substances is of interest and importance. Evidence Acquisition: A PubMed (1960-2012) search was performed to identify articles examining the effects of non-nutritive sweeteners on gastrointestinal physiology and hormone secretion. Evidence Synthesis: The majority of in vitro studies showed that non-nutritive sweeteners can elicit secretion of gut hormones such as glucagon-like peptide 1 and glucose-dependent insulinotropic peptide in enteroendocrine or islet cells. In rodents, non-nutritive sweeteners increased the rate of intestinal glucose absorption, but did not alter gut hormone secretion in the absence of glucose. Most studies in humans have not detected effects of non-nutritive sweeteners on gut hormones or glucose absorption. Of eight human studies, one showed increased glucose-stimulated glucagon-like peptide 1 secretion after diet soda consumption, and one showed decreased glucagon secretion after stevia ingestion. Conclusions: In humans, few studies have examined the hormonal effects of non-nutritive sweeteners, and inconsistent results have been reported, with the majority not recapitulating in vitro data. Further research is needed to determine whether non-nutritive sweeteners have physiologically significant biological activity in humans. 相似文献
992.
Dempster DW Zhou H Recker RR Brown JP Bolognese MA Recknor CP Kendler DL Lewiecki EM Hanley DA Rao DS Miller PD Woodson GC Lindsay R Binkley N Wan X Ruff VA Janos B Taylor KA 《The Journal of clinical endocrinology and metabolism》2012,97(8):2799-2808
Context: Recent studies on the mechanism of action (MOA) of bone-active drugs have rekindled interest in how to present and interpret dynamic histomorphometric parameters of bone remodeling. Objective: We compared the effects of an established anabolic agent, teriparatide (TPTD), with those of a prototypical antiresorptive agent, zoledronic acid (ZOL). Design: This was a 12-month, randomized, double-blind, active-comparator controlled, cross-sectional biopsy study. Setting: The study was conducted at 12 U.S. and Canadian centers. Subjects: Healthy postmenopausal women with osteoporosis participated in the study. Interventions: Subjects received TPTD 20 μg once daily by sc injection (n = 34) or ZOL 5 mg by iv infusion at baseline (n = 35). Main Outcome Measures: The primary end point was mineralizing surface/bone surface (MS/BS), a dynamic measure of bone formation, at month 6. A standard panel of dynamic and static histomorphometric indices was also assessed. When specimens with missing labels were encountered, several methods were used to calculate mineral apposition rate (MAR). Serum markers of bone turnover were also measured. Results: Among 58 subjects with evaluable biopsies (TPTD = 28; ZOL = 30), MS/BS was significantly higher in the TPTD group (median: 5.60 vs. 0.16%, P < 0.001). Other bone formation indices, including MAR, were also higher in the TPTD group (P < 0.05). TPTD significantly increased procollagen type 1 N-terminal propeptide (PINP) at months 1, 3, 6, and 12 and carboxyterminal cross-linking telopeptide of collagen type 1 (CTX) from months 3 to 12. ZOL significantly decreased PINP and CTX below baseline at all time points. Conclusions: TPTD and ZOL possess fundamentally different mechanisms of action with opposite effects on bone formation based on this analysis of both histomorphometric data and serum markers of bone formation and resorption. An important mechanistic difference was a substantially higher MS/BS in the TPTD group. Overall, these results define the dynamic histomorphometric characteristics of anabolic activity relative to antiresorptive activity after treatment with these two drugs. 相似文献
993.
Kulis S Hodge DR Ayers SL Brown EF Marsiglia FF 《The American journal of drug and alcohol abuse》2012,38(5):444-449
Background and objective: This article explores the aspects of spirituality and religious involvement that may be the protective factors against substance use among urban American Indian (AI) youth. Methods: Data come from AI youth (N = 123) in five urban middle schools in a southwestern metropolis. Results: Ordinary least squares regression analyses indicated that following Christian beliefs and belonging to the Native American Church were associated with lower levels of substance use. Conclusions and Scientific Significance: Following AI traditional spiritual beliefs was associated with antidrug attitudes, norms, and expectancies. Having a sense of belonging to traditions from both AI cultures and Christianity may foster integration of the two worlds in which urban AI youth live. 相似文献
994.
Lee LF Logronio K Tu GH Zhai W Ni I Mei L Dilley J Yu J Rajpal A Brown C Appah C Chin SM Han B Affolter T Lin JC 《Proceedings of the National Academy of Sciences of the United States of America》2012,109(31):12674-12679
Genetic variation in the IL-7 receptor-α (IL-7R) gene is associated with susceptibility to human type 1 diabetes (T1D). Here we investigate the therapeutic efficacy and mechanism of IL-7Rα antibody in a mouse model of T1D. IL-7Rα antibody induces durable, complete remission in newly onset diabetic mice after only two to three injections. IL-7 increases, whereas IL-7Rα antibody therapy reduces, the IFN-γ-producing CD4(+) (T(H)1) and IFN-γ-producing CD8(+) T cells. Conversely, IL-7 decreases and IL-7Rα antibody enhances the inhibitory receptor Programmed Death 1 (PD-1) expression in the effector T cells. Programmed Death 1 blockade reversed the immune tolerance mediated by the IL-7Rα antibody therapy. Furthermore, IL-7Rα antibody therapy increases the frequency of regulatory T cells without affecting their suppressor activity. The durable efficacy and the multipronged tolerogenic mechanisms of IL-7Rα antibody therapy suggest a unique disease-modifying approach to T1D. 相似文献
995.
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JC Gray N Navarro-Coy SH Pavitt C Hulme M Godfrey HL Craddock PA Brunton S Brown S Dillon G Dukanovic C Fernandez J Wright H Collier S Swithenbank C Lee TP Hyde 《BMC oral health》2012,12(1):37
ABSTRACT: BACKGROUND: According to the UK Adult Dental Health Survey (2009) 15% of adults aged 65-74, 30% aged 75-84 and 47% aged >85 years are edentulous and require complete dentures. Patients' quality of life and nutrition status are affected by poor dentures. The quality of the dental impression is the most important issue for improving the fit and comfort of new dentures. There is paucity of RCT evidence for which impression material is best for complete dentures construction. This study aims to compare two impression materials for effectiveness and cost effectiveness. METHODS: IMPROVDENT is a double-blind crossover trial comparing the use of alginate and silicone, two commonly used denture impression materials, in terms of patient preference and cost-effectiveness. Eighty five edentulous patients will be recruited and provided with two sets of dentures, similar in all aspects except for the impression material used (alginate or silicone). Patients will try both sets of dentures for a two-week period, unadjusted, to become accustomed to the feel of the new dentures (habituation period). Patients will then wear each set of dentures for a period of 8 weeks (in random order) during which time the dentures will be adjusted for optimum comfort. Finally, patients will be given both sets of dentures for a further two weeks to wear whichever denture they prefer (confirmation period). Patients will be asked about quality of life and to rate dentures on function and comfort at the end of each trial period and asked which set they prefer at the end of the habituation period (unadjusted denture preference) and confirmation period (adjusted denture preference). A health economic evaluation will estimate incremental cost-effectiveness ratios of producing dentures from the two materials. A qualitative study will investigate the impact of dentures on behaviour and quality of life. Funding: IMPROVDENT is funded by NIHR RfPB (PB-PG-0408-16300). DISCUSSION: This trial aims to provide evidence on the costs and quality of dentures cast from two different commonly used impression materials; the intention is to significantly impact on the quality of denture production within NHS dentistry. Trial Registration ISRCTN Register: ISRCTN01528038 UKCRN Portfolio ID: 8305. 相似文献
999.
目的 探讨孤立性骨浆细胞瘤的诊断和治疗,总结其临床特点,以提高临床诊治水平.方法 收集中山大学孙逸仙纪念医院白2007年4月至2011年6月收治7例孤立性骨浆细胞瘤患者的临床资料并对其临床特点、诊断标准及治疗和预后作一回顾性分析.结果 所有病例均经病理证实为骨浆细胞瘤并符合孤立性骨浆细胞瘤的诊断标准,其中1例伴POEMS综合征(多神经病、器官巨大症、内分泌病、M蛋白和皮肤病变综合征),1例术后6个月出现多处骨转移.所有患者治疗后随访1~13个月,平均随访时间为4个月.其中5例患者预后良好,随访期间未出现病情进展.结论 孤立性骨浆细胞瘤好发于中老年,是少见的低度恶性肿瘤.主要依靠病理确诊,手术结合适当剂量的放疗是其治疗的最佳手段. 相似文献
1000.