人Flt3配体基因的克隆及其在CHO细胞中的表达

目的克隆人Flt3配体（Flt3 LIg and，FL），并在CHO细胞中进行表达。方法从健康人外周血中提取总RNA，通过RT-PCR技术，扩增Flt3配体胞外区cDNA功能性片段，经DNA测序证实后，将得到的片段基因插入pcDNA3．0表达载体，构建了pcDNA3．0-FL真核表达载体；将重组质粒pcDNA3．0-FL转染CHO细胞．经G418筛选出阳性细胞克隆，扩大培养，提取细胞总蛋白，用SDS—PAGE分离并Western blotting检测到在相对分子质量约24000处有一显色条带。结果FL胞外区cDNA被正确克隆到真核表达载体pcDNA3．0中并在CHO细胞中成功表达。结论成功构建了真核表达载体pcDNA3．0-FL并在CHO细胞中成功表达，为FL的相关研究和应用开发奠定了基础。     

Cardiovascular indices of physiological arousal in boys with fragile X syndrome

In this study, the relationship between physiological arousal, as indexed by heart rate variability, was examined in boys with fragile X syndrome (FXS) and typically developing boys matched on chronological age. In addition, the relationship of heart activity to clinical and molecular factors in the group of boys with FXS was examined. Results suggest that boys with FXS have higher levels of heart activity during the passive phases, as reflected in shorter heart periods. This high level of heart activity appears to be due to increased sympathetic activity and reduced parasympathetic activity. Boys with FXS did not display the expected patterns of heart activity in response to phases of increasing challenge, and sympathetic and parasympathetic systems did not appear coordinated in these boys with FXS. Clinical factors may be related to neural regulation of heart activity while molecular factors do not appear to be.     

Bovine colostrum supplementation does not affect plasma buffer capacity or haemoglobin content in elite female rowers

It has been reported that bovine colostrum (BC) supplementation improves buffer capacity () during exercise, but whether the improvement results from changes in tissue and/or blood buffer systems has not been determined. The purpose of the present study was to examine the effect of supplementation with BC on blood buffer systems. Thirteen elite females rowers were supplemented with 60 g·day^–1 of either BC (n=6) or whey protein (WP, n=7) during 9 weeks of pre-competition training in a randomised, double-blind, placebo-controlled, parallel design. All subjects undertook the study as a group and completed the same training program. Resting haemoglobin (Hb) concentration and plasma buffer capacity (p) (determined by titration with HCl) were measured pre- and post-supplementation. There were no differences in macronutrient intakes (P>0.56) or training volumes (P>0.99) between BC and WP during the study period. There were no differences in Hb [BC 13.28 (0.28) mg·dl^–1, WP 13.70 (0.26) mg·dl^–1; P=0.45] or p [BC 14.8 (1.1) nmol HCl·ml^–1·pH^–1, WP 14.8 (0.5) nmol HCl·ml^–1·pH^–1; P=0.68] between groups at week 0. p increased in both groups during the study period (P<0.001), but the increases were not significantly different between groups (P=0.52). Hb did not change significantly in either group (P=0.35). These data indicate that supplementation with BC does not affect p or Hb. We therefore suggest that adaptations in tissue buffer systems are responsible for the previously reported increases in buffer capacity that result from BC supplementation.     

Objective stress monitoring based on wearable sensors in everyday settings

Abstract

Monitoring people’s stress levels has become an essential part of behavioural studies for physical and mental illnesses conducted within the biopsychosocial framework. There have been several stress assessment studies in laboratory-based controlled settings. However, the results of these studies do not always translate effectively to an everyday context. The current state of wearable sensor technology allows us to develop systems measuring the physiological signals reflecting stress 24/7 while capturing the context. In this paper, we present a stress monitoring system that provides objective daily stress measurements in everyday settings based on three physiological signals: electrocardiogram (ECG), photoplethysmogram (PPG), and galvanic skin response (GSR) using Shimmer3 ECG, Shimmer3 GSR+, and Empatica E4 wearable sensors. We perform controlled stress assessment experiments on 17 participants in which we successfully detect stress with a 94.55% accuracy for 10-fold cross-validation and an 85.71% accuracy for subject-wise cross-validation. In everyday settings, the system assesses stress with an 81.82% accuracy. We also examine whether motion artefacts affect stress assessment and filter the low-confidence readings to minimise false alarms.     

Early-life epileptiform discharges exert both rapid and long-lasting effects on AMPAR subunit composition and distribution in developing neurons

The perinatal period of brain is characterized by dynamic changes in structure and high propensity for epilepsy. Animal models have shown that alterations of AMPA receptor (AMPAR) assembly or function may be related to seizure-induced cell damage, long-lasting impairments in brain development and seizure threshold. However, effects of earlier epileptiform discharges on AMPAR composition and sub-cellular distribution remain understudied. In this study, we analyzed age-dependent variation of relative GluR1 and GluR2 protein levels in primary cultured rat cortical neurons at 7 DIV, 12 DIV, 17 DIV and 21 DIV. By inducing a single event of epileptiform activity at 6 DIV, we tested the effects of early-life seizure-like insults on AMPAR subunit distribution. We found a significant increase in synaptosomal membrane GluR1 expression in magnesium-free (MGF) medium-treated neurons at each time point detected (p < 0.05), while GluR2 expression increased at 7 DIV, and declined at 17 DIV and 21 DIV respectively (p < 0.05). That is, a trend of high GluR1 with much lower GluR2 expression on the surface membrane of epileptiform discharges experienced neurons over time in culture was presented. These findings in an in vitro model of early-life seizure may inform rodent models of epilepsy, as well as the cellular mechanism involved in epilepsy-associated brain dysfunction.     

Hepatic elimination of drugs with concentration-dependent serum protein binding

For a drug with concentration-dependent serum protein binding, the unbound fraction of drug decreases during the drug elimination process. The clearance of the drug at a given blood flow rate is lower than would be expected from the observed unbound fraction in venous blood from a noneliminating organ. Based on both the well-stirred and parallel tube models, simulations demonstrated that consideration of concentration-dependent binding during drug elimination is important when the intrinsic clearance is higher than the blood flow and when the unbound drug concentration is much greater than the dissociation equilibrium constant of the binding complex.Supported in part by Grant GM 28423 from the National Institutes of General Medical Sciences, NIH.     

北京市房山区某初中学生膳食营养素摄入与体质健康的相关性研究

目的 了解北京市房山区某初中学生膳食营养素摄入与体质健康状况的关系,为提高青少年体质健康状况提供依据。方法 采取整群抽样方法,选取北京市房山区某初中3个年级学生进行体质健康测试、3 d 24 h膳食回顾调查及营养知-信-行（K-A-P）问卷调查。结果 共有效调查181名学生,女生92人（50.83%）,男生89人（49.17%）。该校初中生体质达标率为34.81%,性别差异有统计学意义（Ρ<0.05）;体质达标学生膳食营养素摄入较好,但钙的日均摄入量仅为推荐摄入量（RNI）的43.74%;体质未达标学生9种营养素的日均摄入量均低于体质达标学生,差异均有统计学意义（均Ρ<0.05）,其中维生素A及钙的日均摄入量低于RNI的30%,蛋白质、维生素B₂、维生素C、锌、硒、铁也仅达到RNI的40%~60%;体质达标学生营养K-A-P得分优于未达标学生,差异有统计学意义（Ρ<0.01）;Pearson相关性分析显示蛋白质（r=0.706,Ρ<0.01）及钙（r=0.636,Ρ<0.01）的摄入与体质健康呈强相关。结论 北京市房山区某初中学生体质健康状况较差,膳食营养素摄入与体质健康有相关性,建议通过合理膳食来增强学生体质。     

兰州市城区102例乳母膳食营养状况及其与乳汁成分关系

目的 了解兰州市城区乳母膳食营养状况及其与乳汁成分的关系。方法 招募102位乳母,通过问卷调查其基本情况和膳食状况,计算膳食营养素摄入量,采集血液样本检测血红蛋白和微量元素水平,采集母乳分析体质指数及宏量营养素摄入和乳汁成分的关系。结果 乳母能量摄入量中位数为1 507.5（1 245.5,1 954.5）kcal,能量和宏量营养素及多种微量营养素摄入量均不足,蛋白质、脂肪和碳水化合物供能比分别为13.72%、25.67%、60.90%;乳汁中脂肪、总蛋白质、糖类、干物质、能量的含量分别为（4.33±1.23）g/100 mL、（1.23±0.24）g/100 mL、（7.07±0.32）g/100 mL、（12.82±1.13）g/100 mL、（73.70±10.93）kcal/100 mL。不同BMI分组乳母乳汁中脂肪、干物质以及能量含量不同（均P<0.05）,超重/肥胖组乳母乳汁中能量、脂肪以及干物质含量高。乳汁成分和乳母膳食宏量营养素之间未发现相关性（均P>0.05）。乳母血红蛋白平均含量为（137.23±1.10）g/L,7例（7.53%）贫血,乳母缺乏的微量元素主要为镁（24.73%）和铁（7.53%）。结论 需要加强对乳母的营养宣教,鼓励其合理膳食,定期检测血红蛋白浓度,及时发现健康问题并改善。     

海南省“营养改善计划”某试点地区中小学生贫血状况及影响因素分析

目的 分析海南省“农村义务教育学生营养改善计划”（简称“计划”）某试点地区中小学生贫血的变化趋势及影响因素。方法 2014—2017年采用分层整群随机抽样法,在实施“计划”的重点监测县抽取中小学生进行血红蛋白等生化指标检测及问卷调查。多组均值间比较采用方差分析,率的比较采用χ²检验,贫血影响因素分析采用二分类Logistic回归。结果 2014—2017年共抽取学生2 590人,各年血红蛋白平均水平分别为（138.1±12.0）、（136.4±13.4）、（138.1±12.4）、（138.1±15.4）g/L,差异无统计学意义（P>0.05）。4年来各年贫血率分别为5.4%、5.4%、4.5%、6.7%,变化趋势无统计学意义（P>0.05）;其中2015年初中生贫血率高于小学生（P<0.05）,其余年度小学、初中生间,男、女生间贫血率差异均无统计学意义（均P>0.05）。Logistic回归分析结果显示,少数民族学生（OR=6.947）和维生素A亚临床缺乏/缺乏学生（OR=2.030）发生贫血的风险更高。结论 该地区中小学生贫血状况改善不明显,少数民族和维生素A亚临床缺乏/缺乏学生是需改善贫血的重点人群。     

内外引流与生长抑素治疗十二指肠损伤临床分析

目的：探讨十二指肠损伤综合治疗的方法及结果。:8列十二指肠损伤采用单纯修补,肠腔内造口置管减压,外周双套管冲洗引流,抑制胃肠液分泌,以及TPN支持促使十二指肠损伤一期愈合。结果：8例病人全部治愈。结论：十二指肠损伤修补良好的内外环境、努力改善病人的内稳态对保证十二指肠损伤的愈合有着重要的意义。