P300 amplitude is determined by target-to-target interval

P300 event-related brain potential (ERP) measures are affected by target stimulus probability, the number of nontargets preceding the target in the stimulus sequence structure, and interstimulus interval (ISI). Each of these factors contributes to the target-to-target interval (TTI), which also has been found to affect P300. The present study employed a variant of the oddball paradigm and manipulated the number of preceding nontarget stimuli (0, 1, 2, 3) and ISI (1, 2, 4 s) in order to systematically assess TTI effects on P300 values from auditory and visual stimuli. Number of preceding nontargets generally produced stronger effects than ISI in a manner suggesting that TTI determined P300 measures: Amplitude increased as TTI increased for both auditory and visual stimulus conditions, whereas latency tended to decrease with increased TTI. The finding that TTI is a critical determinant of P300 responsivity is discussed within a resource allocation theoretical framework.     

Key properties of D‐optimal designs for event‐related functional MRI experiments with application to nonlinear models

To properly formulate functional magnetic resonance imaging (fMRI) experiments with complex mental activity, it is advantageous to permit great flexibility in the statistical components of the design of these studies. The length of an experiment, the placement of various stimuli and the modeling approach used all affect the ability to detect mental activity. Major advances in understanding the implications of various designs of fMRI experiments have taken place over the last decade. Nevertheless, new and increasingly difficult issues relating to the modeling of hemodynamic responses and the detection of activated brain regions continue to arise because of the increasing complexity of the experiments. In this article, the D‐optimality criterion is used in conjunction with a genetic algorithm to create probability‐based design generators for the selection of designs in event‐related fMRI experiments where the hemodynamic response function is modeled with a function that is nonlinear in the parameters. The designs produced by these generators are shown to perform well compared with locally D‐optimal designs and provide insight into optimal design characteristics that investigators can utilize in the selection of interstimulus intervals. Designs with these characteristics are shown to be applicable to fMRI studies involving one or two stimulus types. The designs are also shown to be robust with respect to misspecification of an AR(1) error autocorrelation and compare favorably with a maximin procedure. Copyright © 2012 John Wiley & Sons, Ltd.     

用Web of Science-SCI Expanded收录泌尿科及肾病学期刊

“Web of Science-SCI Expanded”是美国科学信息所（Institute for Scien-tific Information）开发的科学引文索引数据库（SCI：Science Citation Index）网络版。《科学引文索引》（Science Citation Index，简称SCI），是由美国科学信息所（ISI）1961年创办并编辑出版的，SCI已出版了印刷版、光盘版、磁带版、联机数据库等多种版本。1997年ISI推出网络版的ISI Web of knowledge的检索平台，这借助于WWW超文本的特性，构成了引文索引最理想的介质，用户通过该数据库，可以快速的进行信息检索，迅速了解学科的研究动态。     

Comparative analysis of anxiety/depression scores in COVID-19 patients with disease severity,sleep patterns,and certain laboratory test results

IntroductionCoronavirus disease 2019 (COVID-19) is associated with severe emotional changes. This research aims to investigate the prevalence of anxiety and depression in COVID-19 patients and its relationship with disease severity, sleep patterns, lifestyle, and specific laboratory test results.Material and methodsAn observational study of 52 Chinese patients with COVID-19 was conducted to assess the relation between anxiety and depression (evaluated with the Hospital Anxiety and Depression Scale) and laboratory findings (lymphocytes, C-reactive proteins, leukocytes, alanine aminotransferase, aspartate aminotransferase). The relationships between the severity of COVID-19 in patients, the Insomnia Severity Index (ISI) score, and the Hospital Anxiety and Depression Scale (HADS) score were also investigated.ResultsThere were statistically significant associations between disease, smoking, and HADS-A scores (p = 0.011/0.020). The HADS-D score of patients with the disease was higher than in those without a past medical history (p = 0.008). The difference in C-reactive protein (CRP) between different lung infections, the HADS-A and HADS-D scores between different ages and ISI groups, and the correlation between the two scores were statistically significant.ConclusionsAnxiety and depression are associated with poor sleep quality, smoking, and past medical history in patients with COVID-19. Additionally, anxiety and depression were seen to coexist, and there was a positive correlation between them. Further, the inflammatory index CRP was significantly increased in bilateral lung infections.     

Lactation intensity and fasting plasma lipids,lipoproteins, non-esterified free fatty acids,leptin and adiponectin in postpartum women with recent gestational diabetes mellitus: The SWIFT cohort

Objectives

Lactation may influence future progression to type 2 diabetes after gestational diabetes mellitus (GDM). However, biomarkers associated with progression to glucose intolerance have not been examined in relation to lactation intensity among postpartum women with previous GDM. This study investigates whether higher lactation intensity is related to more favorable blood lipids, lipoproteins and adipokines after GDM pregnancy independent of obesity, socio-demographics and insulin resistance.

Methods

The Study of Women, Infant Feeding, and Type 2 Diabetes (SWIFT) is a prospective cohort study that recruited 1035 women diagnosed with GDM by the 3-h 100 g oral glucose tolerance tests (OGTTs) after delivery of a live birth in 2008–2011. Research staff conducted 2-h 75 g OGTTs, and assessed lactation intensity, anthropometry, lifestyle behaviors and socio-demographics at 6–9 weeks postpartum (baseline). We assayed fasting plasma lipids, lipoproteins, non-esterified free fatty acids, leptin and adiponectin from stored samples obtained at 6–9 weeks postpartum in 1007 of the SWIFT participants who were free of diabetes at baseline. Mean biomarker concentrations were compared among lactation intensity groups using multivariable linear regression models.

Results

Increasing lactation intensity showed graded monotonic associations with fully adjusted mean biomarkers: 5%–8% higher high-density lipoprotein cholesterol (HDL-cholesterol), 20%–28% lower fasting triglycerides, 15%–21% lower leptin (all trend P-values < 0.01), and with 6% lower adiponectin, but only after adjustment for insulin resistance (trend P-value = 0.04).

Conclusion

Higher lactation intensity was associated with more favorable biomarkers for type 2 diabetes, except for lower plasma adiponectin, after GDM delivery. Long-term follow-up studies are needed to assess whether these effects of lactation persist to predict progression to glucose intolerance.     

Differences in Glucose Metabolism Among Women With Spinal Cord Injury May Not Be Fully Explained by Variations in Body Composition

ObjectiveTo investigate the differences in glucose metabolism among women with paraplegic, and tetraplegic spinal cord injury (SCI) in comparison to their able-bodied (AB) counterparts after adjusting for differences in body composition.DesignCross-sectional study. After an overnight fast, each participant consumed a 75-g glucose solution for oral glucose tolerance test (OGTT). Blood glucose, insulin, and C-peptide concentrations were analyzed before and 30, 60, 90, and 120 minutes after ingesting glucose solution. Insulin sensitivity index (ISI) was estimated using the Matsuda index. Percentage fat mass (%FM) and total body lean mass (TBLM) were estimated using data from dual-energy x-ray absorptiometry. Visceral fat (VF) was quantified using computed tomography. Outcome measures were compared among groups using analysis of covariance with %FM (or VF) and TBLM as covariates.SettingResearch university.ParticipantsWomen (N=42) with SCI (tetraplegia: n=8; paraplegia: n=14) and their race-, body mass index-, and age-matched AB counterparts (n=20).InterventionsNot applicable.ResultsAt fasting, there was no difference in glucose homeostasis (glucose, insulin, C-peptide concentrations) among 3 groups of women. In contrast, glucose, insulin, and C-peptide concentrations at minute 120 during OGTT were higher in women with tetraplegia versus women with paraplegia and AB women (P<.05, adjusted for TBLM and %FM). In addition, women with tetraplegia had lower ISI (P<.05, adjusted for TBLM and %FM) versus AB women. These differences remained after adjusting for VF and TBLM.ConclusionOur study confirms that impaired glucose metabolism among women with tetraplegia may not be fully explained by changes in their body composition. Future studies exploring additional factors involved in glucose metabolism are warranted.     

能量缓释营养液防治夜间低血糖和改善胰岛素敏感性的研究

目的　通过临睡前补充能量缓释营养液观察其对药物继发性失效的2型糖尿病病人夜间低血糖和清晨反应性高血糖的影响及其对胰岛素敏感性的改善作用。方法　按一定的要求选择2型糖尿病住院病人40例, 按病人和家属的意愿分为普通糖尿病治疗饮食组(A组) 和临睡前补充能量缓释营养液(益力佳SR) 的糖尿病治疗饮食干预组(B组)。A组在胰岛素治疗的基础上, 进食普通糖尿病饮食定量治疗; B组的热能摄入量及三大产热营养素的供热比同A组, 但提取100kcal用益力佳SR替代作为临睡前点心, 剩下的热量按照1 /3、1 /3、1 /3的方式分餐摄取, 持续14d。两组病人每天都于22∶00, 24∶00, 3∶00, 7∶00检测血糖, 并观察夜间低血糖反应的发生率。分别于治疗前、干预后第7d和干预后第14d分别检测空腹血糖和空腹胰岛素, 以观察胰岛素敏感性的变化情况。结果　两组病人调整期3∶00的血糖、空腹血糖间差异均有显著性意义, A组不同时期胰岛素敏感性(ISI) 间差异无显著性意义, B组第14dISI与干预前比较差异有显著性意义(P<0. 05), 与A组比较差异有显著性意义(P<0. 05)。B组第14d的胰岛素分泌功能指数(IS) 与第1d比较差异有显著性意义(P<0. 05 )。结论　临睡前补充相当于全日总热能5% ~10%的营养液, 可有效防治多次皮下胰岛素注射治     

SCI收录期刊概况及英文稿件

本文以最新的美国科学情报研究所(ISI)出版物为基准,概述了ISI出版物,特别是SCI收录期刊的概况,同时略以医学影像学期刊为详.本文还基于目前SCI收录期刊投稿要求,概述了英文稿件的写作及投稿事项.     

两种凝血酶原时间试剂测定结果比较

目的:了解两种凝血酶原时间(PT)试剂测定结果差异。方法:同时用两种不同ISI的PT试剂测定健康人及口服抗凝药物患者的INR值,应用统计学方法对测定结果进行比较。结果:两种试剂在健康人,口服抗凝药物患者的测定结果差异均有非常显著性(P<0.01)。结论:建议在日常工作中选择ISI值接近1.0的凝血酶原时间(PT)试剂。     

滇越金线兰活性部位降血糖、增敏胰岛素和抗氧化活性研究

采用高糖高脂饮食联合低剂量STZ诱导造成糖尿病大鼠模型,实验组大鼠分别灌胃给予滇越金线兰总膏和溶剂萃取法所得各极性部位,测定给药后大鼠血糖、胰岛素敏感性、抗氧化活性及NO水平等相关指标。胰腺切片,进行病理学检查。与模型组相比,乙酸乙酯部位给药组的随机血糖可见明显降低,从给药前402．66至226．26mg／dl（P〈0．05）,而且该组大鼠的体重值明显高于模型对照组,同时能提高胰岛素敏感性,改善高糖负荷以后的糖耐量;胰腺细胞形态较模型组有明显改善;同时SOD活性增加,NO含量均显著降低。表明滇越金线兰的乙酸乙酯部位是其降血糖的主要活性部位,其作用机制可能与改善胰岛素抵抗、增强机体抗氧化活性和降低血浆NO等机制有关。