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排序方式: 共有490条查询结果,搜索用时 125 毫秒
1.
《Neuropsychopharmacology》2019,85(11):956-965
BackgroundBinge eating and other forms of disordered eating behavior (DEB) are associated with failed inhibitory control. This study investigated the neural correlates of failed inhibitory control as a potential biomarker for DEB.MethodsThe study used prospective longitudinal data from the European IMAGEN study adolescent cohort. Participants completed baseline assessments (questionnaires and a brain scan [functional magnetic resonance imaging]) at 14 years of age and a follow-up assessment (questionnaires) at 16 years of age. Self-reported binge eating and/or purging were used to indicate presence of DEB. Neural correlates of failed inhibition were assessed using the stop signal task. Participants were categorized as healthy control subjects (reported no DEB at both time points), maintainers (reported DEB at both time points), recoverers (reported DEB at baseline only), and developers (reported DEB at follow-up only). Forty-three individuals per group with complete scanning data were matched on gender, age, puberty, and intelligence (N = 172).ResultsAt baseline, despite similar task performance, incorrectly responding to stop signals (failed inhibitory control) was associated with greater recruitment of the medial prefrontal cortex and anterior cingulate cortex in the developers compared with healthy control subjects and recoverers.ConclusionsGreater recruitment of the medial prefrontal and anterior cingulate regions during failed inhibition accords with abnormal evaluation of errors contributing to DEB development. As this precedes symptom onset and is evident despite normal task performance, neural responses during failed inhibition may be a useful biomarker of vulnerability for DEB. This study highlights the potential value of prospective neuroimaging studies for identifying markers of illness before the emergence of behavior changes. 相似文献
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Sakashita N Ando Y Obayashi K Terazaki H Yamashita T Takei M Kinjo M Takahashi K 《Virchows Archiv : an international journal of pathology》2000,436(4):345-350
We report an autopsy case of a pedigree of familial amyloidotic polyneuropathy (FAP) with a mutation of isoleucine-50 transthyretin
(ATTR Ser50Ile). A 47-year-old man started developing severe diarrhea and weight loss at age 41 years, followed by urinary
incontinence, autonomic-nervous-system abnormalities and serious heart failure; the diagnosis of FAP (ATTR Ser50Ile) was made
on the basis of genetic, histochemical and immunohistochemical analysis. Six years after the initial symptoms, he died of
septic shock. Autopsy revealed suppurative peritonitis, perforation of the sigmoid colon and marked systemic amyloid deposition.
The total amount of amyloid deposited in the heart was greatly increased and was much lower in the thyroid gland and kidneys
compared with amyloid deposits in ordinary FAP (ATTR Val30Met). Amyloid deposition in peripheral vessel walls was prominent,
particularly in lymphatics and veins. His elder sister, 54 years old, started to develop orthostatic hypotension at age 49
years, followed by dysesthesia, diarrhea and severe congestive heart failure. Endomyocardial biopsy revealed severe TTR–amyloid
deposition; ultrastructural examination demonstrated that amyloid fibrils were deposited disproportionately and extended radially
around microvessels. These characteristic patterns of systemic amyloid deposition and distinct clinical manifestations, especially
in the cardiovascular system, are considered to be a characteristic feature of ATTR Ser50Ile amyloidosis.
Received: 31 August 1999 / Accepted: 19 October 1999 相似文献
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Covalent modifications of histones integrate intracellular and extracellular cues to regulate the genome. H3 Lys 9 methylation (H3K9me) can direct heterochromatin formation and DNA methylation, while phosphorylation of H3 Ser 10 (H3S10p) drives gene activation and chromosome condensation. To examine the relationship between H3S10p, H3K9me, and DNA methylation in Neurospora crassa, we built and tested mutants of the putative H3S10 phosphatase, PP1. A PP1-impaired mutant showed increased H3S10p and selective reduction of methylation of H3K9 and DNA. Similarly, amino acid substitutions of H3S10 abolished methylation of H3K9 and DNA. Thus, H3S10 dephosphorylation by PP1 is required for DNA methylation of some loci. 相似文献
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目的 应用DNA条形码技术对翻白草及易混品委陵菜进行分子鉴定,保障药材质量和临床用药安全。方法 提取翻白草及委陵菜的基因组DNA,扩增内转录间隔区2(ITS2)序列并双向测序,所得序列用SeqMan软件校对、拼接;在线双序列比对翻白草对照药材(FR)及委陵菜对照药材(WR)的ITS2序列,并预测其二级结构;从GenBank下载部分相关序列,运用MEGA X软件进行多序列比对,分析序列变异位点,计算种内、种间遗传距离,采用邻接法(NJ)构建系统进化树。结果 所有样品均成功扩增出ITS2序列,翻白草和委陵菜的ITS2序列长度均为210 bp。双序列比对结果表明,FR与WR的ITS2序列相似性为92.9%,二级结构存在明显差异。多序列分析结果表明,翻白草ITS2序列平均鸟嘌呤(G)+胞嘧啶(C)占比为63.0%,存在2个变异位点,种内遗传距离为0~0.009 6;委陵菜ITS2序列平均G+C占比为64.4%,存在5个变异位点,种内遗传距离为0~0.019 3;种间遗传距离为0.054 8~0.075 8。NJ树结果显示,翻白草、委陵菜聚为不同分支,可明显区分。结论 利用ITS2序列可以准确鉴别翻白草与委陵菜,为保障其安全用药提供了新的技术手段。 相似文献
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447C88 (N-Heptyl-N-(2,4 difluoro-4-6-(2(-4-(2,2 dimethylpropyl)phenyl)ethyl)phenyl)urea) is an inhibitor of human microsomal AcylCoA:Cholesterol acyltransferase (ACAT) with an IC50 of 10.2 ng·ml–1 (23 nM). It is poorly absorbed but 5 mg·kg–1·day–1 completely abolishes the rise in plasma cholesterol in cholesterol-fed rats.In this study, twelve healthy, male volunteers received single, oral doses of 25, 50, 100, 200, 400 and 800 mg of 447C88 (n+8) or placebo (n+4) with food in a double-blind study with at least a week between occasions. The 400 mg dose was repeated after an overnight fast. Subsequently, fourteen different volunteers received a single 200 mg dose of 447C88 (n+8) or placebo (n+6) with food and, a week later, the same dose twice daily for 10 days; all doses were given with food.All doses were well tolerated with no significant changes in vital signs, full blood counts or plasma biochemical profiles. Plasma concentrations of 447C88 were unquantifiable after the fasting dose and low after all other doses. Mean Cmax and AUC were 1.8 ng·ml–1 and 9.0 ng·ml–1·h after 200 mg rising to 5.4 ng·ml–1 and 23.8 ng·ml–1·h respectively after 800 mg; t1/2 was 1.3 to 5.2 h. After 10 days dosing, plasma 447C88 concentrations were higher in the evening than the morning probably due to administration of the evening dose with more food. There were no significant changes in plasma triglcerides or total, LDL- or HDL-cholesterol after dosing with 447C88. 相似文献
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《Nutrition, metabolism, and cardiovascular diseases : NMCD》2022,32(8):1841-1850
Background and aimsHeart failure (HF) patients are at risk of developing type 2 diabetes. This study examined the association between adherence to the Dietary Approaches to Stop Hypertension (DASH) diet and insulin resistance among U.S. adults with HF.Methods and resultsUsing data from National Health and Nutrition Examination Survey 1999–2016 cycles, we included 348 individuals aged 20+ years with HF and no history of diabetes. DASH diet adherence index quartile 1 indicated the lowest and quartile 4 indicated the highest adherence. The highest level of insulin resistance was defined by the upper tertile of the Homeostatic Model Assessment of Insulin Resistance (HOMA-IR). Associations between level of insulin resistance and DASH diet adherence and its linear trends were examined using logistic regressions. Trend analyses showed that participants in upper DASH diet adherence index quartiles were more likely older, female, non-Hispanic White, of normal weight, and had lower levels of fasting insulin than those in lower quartiles. Median values of HOMA-IR from lowest to highest DASH diet adherence index quartiles were 3.1 (interquartile range, 1.8–5.5), 2.9 (1.7–5.6), 2.1 (1.1–3.7), and 2.1 (1.3–3.5). Multivariable logistic analyses indicated that participants with the highest compared to the lowest DASH adherence showed 77.1% lower odds of having the highest level of insulin resistance (0.229, 95% confidence interval: 0.073–0.716; p = 0.017 for linear trend).ConclusionGood adherence to the DASH diet was associated with lower insulin resistance among community-dwelling HF patients. Heart healthy dietary patterns likely protect HF patients from developing type 2 diabetes. 相似文献