Different applications of polymerases with and without proofreading activity in single-nucleotide polymorphism analysis

With the completion of the human genome project, single-nucleotide polymorphisms (SNPs) have become the focus of intense study in biomedical research. Polymerase-mediated primer extension has been employed in a variety of SNP assays. However, these SNP assays using polymerase without proofreading function are compromised by their low reliability. Using a newly developed short amplicon harboring restriction enzyme site, EcoR-I, we were able to compare the single-base discrimination abilities of polymerases with and without proofreading function in primer extension in a broad range of annealing temperatures. Thermodynamic analysis demonstrated a striking single-nucleotide discrimination ability of polymerases with proofreading function. Using unmodified 3'-end allele-specific primers, only template-dependent products were generated by polymerase with proofreading activity. This powerful single-base discrimination ability of exo(+) polymerases was further evaluated in primer extension using three types of 3' terminally modified allele-specific primers. As compared with the poor fidelity in primer extension of polymerases lacking 3' exonuclease activity, this study provides convincing evidence that the use of proofreading polymerases in combination with 3'-end modified allele-specific primers can be a powerful new strategy for the development of SNP assays.     

Calcium currents and transmitter output in cultured spinal cord and dorsal root ganglion neurons

The effects of repetitive activation upon voltage-dependent calcium currents (ICa) and transmitter release were studied in dissociated cell cultures of fetal mouse spinal cord and dorsal root ganglion. Sodium and potassium currents were suppressed with tetrodotoxin (TTX) and tetraethylammonium (TEA) ions, 4-aminopyridine (4-AP), and cesium sulfate. Calcium currents were compared under voltage clamp before and after a series of depolarizing clamp pulses in spinal cord (SC) and dorsal root ganglion (DRG) neurons. Repetitive activation resulted in an exponential decline in ICa, with the decrease in ICa being much more marked in DRG compared with SC neurons. Both voltage-dependent inactivation and inactivation related to the intracellular movement of Ca2+ appeared to be involved in the decrement in ICa with repetitive activation. A decrease in transmitter output occurred with repetitive activation in DRG neurons but not in SC neurons (either excitatory or inhibitory). DRG neuron synaptic boutons had fewer mitochondria than did the boutons of either excitatory or inhibitory of SC neurons. The decrement in both ICa and synaptic transmitter output in DRG neurons could last for prolonged periods (at least minutes) following repetitive activation. We hypothesize that this vulnerability of DRG neurons to repetitive activation may be related, at least in part, to a relative incapacity to maintain a low intracellular calcium ion concentration [Ca]i during periods of increased calcium ingress associated with excitation. Such an incapacity to buffer [Ca]i may be one mechanism leading to the inactive synapses seen in some studies in vitro and in vivo of synaptic transmission.     

Diagnosis and taxonomy of periodical psychosis

The concept and taxonomy of periodic psychosis still remains in controversy for the past 100 years. In China, it was first reported by Ji, and thereafter various rinds of terminology and views were given by different authors. In the presentation, clinical investigation and follow up were carried out in 62 cases. In many of these cases, the so-called "periodic psychosis" or "phasophrenia" was early clinical features of schizophrenia or manic-depression. In those cases with apparent symptoms and signs of diencephalic function, differential diagnosis should be carried out from organic brain syndrome. In a small number of cases, their clinical manifestations, conforming to previous diagnostic criteria, might be an uncommon syndrome. It was concluded by the authors that until now periodic could be considered only as a clinical syndrome rather than a disease entity.     

Dietary Habit Is Associated with Depression and Intelligence: An Observational and Genome-Wide Environmental Interaction Analysis in the UK Biobank Cohort

Dietary habits have considerable impact on brain development and mental health. Despite long-standing interest in the association of dietary habits with mental health, few population-based studies of dietary habits have assessed depression and fluid intelligence. Our aim is to investigate the association of dietary habits with depression and fluid intelligence. In total, 814 independent loci were utilized to calculate the individual polygenic risk score (PRS) for 143 dietary habit-related traits. The individual genotype data were obtained from the UK Biobank cohort. Regression analyses were then conducted to evaluate the association of dietary habits with depression and fluid intelligence, respectively. PLINK 2.0 was utilized to detect the single nucleotide polymorphism (SNP) × dietary habit interaction effect on the risks of depression and fluid intelligence. We detected 22 common dietary habit-related traits shared by depression and fluid intelligence, such as red wine glasses per month, and overall alcohol intake. For interaction analysis, we detected that OLFM1 interacted with champagne/white wine in depression, while SYNPO2 interacted with coffee type in fluid intelligence. Our study results provide novel useful information for understanding how eating habits affect the fluid intelligence and depression.     

公立医院优势学科病种绩效管理研究:以骨科为例

目的从循证视角建立公立医院优势学科病种绩效管理工具。方法以波士顿矩阵理论为指导,以“病种均次毛利率、病种均次住院日”为主要指标,“日均毛利率”为辅助指标,采用Microsoft office EXCEL 365 软件进行分析。结果2019年骨科平均住院日为4.99 d,均次平均毛利率为23.62%,日均毛利率平均值为4.73%。骨科200例以上病种、不同亚专科病区病种、同一亚专科病区内不同病种、不同亚专科病区相同病种,绩效均存在差异。结论 管理者应对不同病种绩效指标进行适当校正,探索精细化病种诊疗与管理模式。     

苏州市儿童青少年身高别血压筛查简表的效果评价

目的 基于苏州市7~17岁儿童青少年评价身高别血压筛查简表的效果,为制定儿童青少年血压综合防控策略和措施提供参考。方法 采用分层整群随机抽样方法,2017-2018年抽取苏州市7~17岁学生6 972名,进行问卷调查,测量其身高、体重和血压。依据《7～18岁儿童青少年血压偏高筛查界值(WS/T 610-2018)》为“金标准”,评价根据金标准建立的身高别血压筛查简表筛查正常血压高值和血压偏高的效果。结果 根据金标准和身高别血压筛查简表,苏州7~17岁儿童青少年正常血压高值检出率分别为16.7%和16.6%,血压偏高检出率分别为12.7%和12.8%;配对χ²检验显示两标准评价效果差异无统计学意义(χ²=1.376,P=0.711)。与金标准相比,身高别血压筛查简表筛查正常血压高值,血压偏高具有较好的一致性。筛查正常血压高值的受试者工作特征曲线下面积(95%置信区间)、灵敏度、特异度和Kappa值分别为0.900(0.887~0.913)、83.2%、96.8%和0.803,对应的筛查血压偏高值分别为0.925(0.911~0.938)、86.9%、98.0%和0.848。结论 身高别血压筛查简表使用方便,筛查正常血压高值和血压偏高效果很好。     

Undocumented Migrants Reintroducing COVID-19, Yunnan Province,China

To limit the spread of severe acute respiratory syndrome coronavirus 2, the government of China has been monitoring infected travelers and minimizing cold-chain contamination. However, other factors might contribute to recurring outbreaks. We analyze the role of undocumented migrants as potential transmitters of severe acute respiratory syndrome coronavirus 2 in China.     

The 6-Month Efficacy of an Intensive Lifestyle Modification Program on Type 2 Diabetes Risk Among Rural Women with Prior Gestational Diabetes Mellitus: a Cluster Randomized Controlled Trial

Prevention Science - This study aimed to evaluate the efficacy of an intensive lifestyle modification program tailored to rural Chinese women with prior gestational diabetes mellitus compared with...     

少数民族地区青少年对新冠疫情的认知调查

目的调查少数民族地区青少年对新冠疫情的认知及应对情况。方法采用分层抽样的方法,通过“问卷星”在线平台对香格里拉市1949名在校学生进行调查。结果结果显示,81.94%的学生在2020年1月初之前已知晓疫情;83.12%的学生通过电视和微信知晓疫情;9333%的学生认为病毒通过飞沫传播;94.80%的学生会通过戴口罩、不聚餐等方式进行防护;疫情相关知识的正确率为71.44%。不同年龄、性别、民族、专业、生源地、家庭年收入的学生对部分调查问题的差异有统计学意义(P<0.05)。结论学生对疫情认知整体情况较好,部分问题仍有较大提升空间。学校应做好疫情常态化防控,完善心理疏导体系,多措并举,引导学生做好自我防护。