The neurophysiological bases of EEG and EEG measurement: A review for the rest of us

A thorough understanding of the EEG signal and its measurement is necessary to produce high quality data and to draw accurate conclusions from those data. However, publications that discuss relevant topics are written for divergent audiences with specific levels of expertise: explanations are either at an abstract level that leaves readers with a fuzzy understanding of the electrophysiology involved, or are at a technical level that requires mastery of the relevant physics to understand. A clear, comprehensive review of the origin and measurement of EEG that bridges these high and low levels of explanation fills a critical gap in the literature and is necessary for promoting better research practices and peer review. The present paper addresses the neurophysiological source of EEG, propagation of the EEG signal, technical aspects of EEG measurement, and implications for interpretation of EEG data.     

Correlates of Incident Cognitive Impairment in the REasons for Geographic and Racial Differences in Stroke (REGARDS) Study

Objective: To identify approximately 500 cases of incident cognitive impairment (ICI) in a large, national sample adapting an existing cognitive test-based case definition and to examine relationships of vascular risk factors with ICI. Method: Participants were from the REGARDS study, a national sample of 30,239 African-American and White Americans. Participants included in this analysis had normal cognitive screening and no history of stroke at baseline, and at least one follow-up cognitive assessment with a three-test battery (TTB). Regression-based norms were applied to TTB scores to identify cases of ICI. Logistic regression was used to model associations with baseline vascular risk factors. Results: We identified 495 participants with ICI of 17,630 eligible participants. In multivariable modeling, income (OR 1.83 CI 1.27,2.62), stroke belt residence (OR 1.45 CI 1.18,1.78), history of transient ischemic attack (OR 1.90 CI 1.29,2.81), coronary artery disease(OR 1.32 CI 1.02,1.70), diabetes (OR 1.48 CI 1.17,1.87), obesity (OR 1.40 CI 1.05,1.86), and incident stroke (OR 2.73 CI 1.52,4.90) were associated with ICI. Conclusions: We adapted a previously validated cognitive test-based case definition to identify cases of ICI. Many previously identified risk factors were associated with ICI, supporting the criterion-related validity of our definition.     

Comparison of the direct fluorescence assay and real-time polymerase chain reaction for the detection of influenza virus A and B in immunocompromised patients

OBJECTIVE:

This study evaluated the diagnostic performance of two methods for the detection of influenza virus in immunocompromised transplant patients.

METHODS:

A total of 475 respiratory samples, 236 from patients in a hematopoietic stem cell transplantation program and 239 from kidney transplant patients, were analyzed by a direct fluorescence assay and the Centers for Disease Control real-time polymerase chain reaction protocol for influenza A and B detection.

RESULTS:

Influenza detection using either method was 7.6% in the hematopoietic stem cell transplant group and 30.5% in the kidney transplant patient group. Influenza detection by real-time polymerase chain reaction yielded a higher positive rate compared with fluorescence than that reported by other studies, and this difference was more pronounced for influenza A. The fluorescence assay sensitivity, specificity, positive and negative predictive values, and kappa coefficient were 17.6%, 100%, 1, 0.83, and 0.256, respectively, and lower detection rates occurred in the kidney transplant patients.

CONCLUSIONS:

The real-time polymerase chain reaction performance and the associated turnaround time for a large number of samples support the choice of this method for use in different routine diagnostic settings and influenza surveillance in high-risk patients.     

对维吾尔族学生中应用启发式教学法的效果评价

目的探讨在维吾尔族学生中启发式教学法在心内科教学中的应用与效果。方法将2010级新疆医科大学两个乡村医师班(维吾尔族)的临床医学专业的学生,按整群分组的方法,随机分为实验组68例和对照组各62例,实验组采用启发式教学法,对照组采用传统的教学方法,采用阶段理论测试的方法评估教学效果。结果实验组阶段理论考试成绩显著优于对照组。结论运用启发式教学法进行循环系统教学有利于提高维吾尔学生的理论成绩。     

A source of systematic bias in self-reported physical activity: The cutpoint bias hypothesis

ObjectivesEstimates of adults’ moderate-to-vigorous physical activity (MVPA) based on self-report are generally higher than estimates derived from criterion measures. This study examines a possible explanation for part of this discrepancy: the cutpoint bias hypothesis. This hypothesis proposes that inter- and intra-individual variability in energy expenditure, combined with the fact that adults perform a high proportion of daily activities at or just above the traditional 3 MET cutpoint, result in systematic over-estimates of MVPA.DesignCross-sectional.MethodsTime-use recalls (n = 6862) were collected using the Multimedia Activity Recall for Children and Adults from 2210 adults (1215 female, age 16–93 years) from 16 studies conducted in Australia and New Zealand between 2008-2017. Minutes spent in MVPA were estimated using models with varying levels of intra- and inter-individual (total variability) Unadjusted (0% total variability), Low (11.9%), Best Guess (20.7%), and High (30.0%).ResultsIn the Unadjusted model, participants accumulated an average of 129 (standard deviation 127) min/day of MVPA. Estimated MVPA was 98 (110), 99 (107) and 108 (107) min/day in the Low, Best Guess and High variability models, respectively, with intra-class correlation coefficients with the Unadjusted model ranging from 0.78 to 0.83.ConclusionsThese findings support the hypothesis of a cutpoint bias, which probably contributes to the large disparities seen between self-reported and criterion measures of MVPA. Future studies are needed to confirm these findings using other self-report instruments and in other populations.     

Predictors of discordance in self-report versus device-measured physical activity measurement

Purpose

Accurate measurement of free-living physical activity is challenging in population-based research, whether using device-based or reported methods. Our purpose was to identify demographic predictors of discordance between physical activity assessment methods and to determine how these predictors modify the discordance between device-based and reported physical activity measurement methods.

中国富血小板血浆临床制备方法的研究进展

自体富血小板血浆(PRP)是一种通过离心的方法从自体血中提取出来的血小板浓缩物。近20年来,已经被广泛应用于多种学科,如骨科、口腔颌面外科、整形美容科等。然而,至今,PRP的临床制作方法还没有统一标准,不同的制作方法导致PRP的成分以及临床疗效不同,给临床医务工作者应用PRP造成了诸多困扰。通过检索和分析中国已发表有关PRP制备的文献(中文和英文)发现,国内PRP临床制备方法差异性较大,包括采血量、离心设备、离心次数、离心力、离心时间和PRP制备量等。PRP中血小板富集度和回收率,白细胞浓度等指标也不稳定,亟需更高质量的研究或指南来规范和指导临床PRP的制备。     

无痛肠镜的麻醉用药探讨

目的观察依托咪酯复合舒芬太尼用于无痛肠镜的临床效果及安全性。方法将2010年9月至2012年3月该院收治的80例自愿行无痛肠镜检查患者分为A组和B组,各40例,美国麻醉医师协会（ASA）分级Ⅰ-Ⅱ级。A组单独使用依托咪酯麻醉;B组检查前先给予枸橼酸舒芬太尼0.05μg/kg,2 min后再给予依托咪酯0.2-0.3 mg/kg进行麻醉。比较患者麻醉诱导开始前（T0）、诱导完成后（T1）、检查操作开始时（T2）、术毕时（T3）两组心率（HR）、血压、脉搏血氧饱和度（SpO2）、麻醉诱导时间、苏醒时间以及胃肠道反应、疼痛情况。结果 A组HR、血压诱导后T1时较T0时均有所下降,但均在正常范围之内;B组诱导后T1与T0时HR、血压比较,差异均无统计学意义（P〉0.05）;两组T1、T2时HR、血压均有所下降,与T0比较,差异均有统计学意义（P〈0.05）;在T1、T2时A组HR、血压均低于B组,差异有统计学意义（P〈0.05）;T0、T3时两组HR、血压比较,差异均无统计学意义（P〉0.05）。两组各时间点SpO2值比较,差异无统计学意义（P〉0.05）。A组依托咪酯用量[（58.4±6.1）mg]高于B组[（38.2±2.6）mg],差异有统计学意义（P〈0.05）;A组苏醒时间[（7.9±5.6）min]长于B组[（3.7±1.5）min],差异有统计学意义（P〈0.05）。两组患者在肠镜检查后发生恶心、呕吐方面比较,差异均无统计学意义（P〉0.05）;两组患者肠镜检查后疼痛比较,术后0.5 h及术后2.0 h疼痛B组明显优于A组,差异均有统计学意义（P〈0.05）。结论依托咪酯复合小剂量舒芬太尼用于无痛肠镜麻醉具有良好的镇痛效果及减少胃肠反应,是一种安全、有效的麻醉方法。