Assessment and characterization of phenotypic heterogeneity of anxiety disorders across five large cohorts

To achieve sample sizes necessary for effectively conducting genome‐wide association studies (GWASs), researchers often combine data from samples possessing multiple potential sources of heterogeneity. This is particularly relevant for psychiatric disorders, where symptom self‐report, differing assessment instruments, and diagnostic comorbidity complicates the phenotypes and contribute to difficulties with detecting and replicating genetic association signals. We investigated sources of heterogeneity of anxiety disorders (ADs) across five large cohorts used in a GWAS meta‐analysis project using a dimensional structural modeling approach including confirmatory factor analyses (CFAs) and measurement invariance (MI) testing. CFA indicated a single‐factor model provided the best fit in each sample with the same pattern of factor loadings. MI testing indicated degrees of failure of metric and scalar invariance which depended on the inclusion of the effects of sex and age in the model. This is the first study to examine the phenotypic structure of psychiatric disorder phenotypes simultaneously across multiple, large cohorts used for GWAS. The analyses provide evidence for higher order invariance but possible break‐down at more detailed levels that can be subtly influenced by included covariates, suggesting caution when combining such data. These methods have significance for large‐scale collaborative studies that draw on multiple, potentially heterogeneous datasets. Copyright © 2016 John Wiley & Sons, Ltd.     

捏力类型对健康青年捏力测量的影响

目的探讨捏力类型对捏力测量的影响。方法20名健康青年受试者在标准姿势下用电子捏力计测量3种捏力类型（指尖-指尖型、指头-指头型和指头-指侧型）下的捏力大小,并测量人体学资料。结果指尖-指侧型捏力最大,其次为指头-指头型,指尖-指尖型最小。男性在3种类型下捏力均明显大于女性（P〈0.01）;男性及女性其利手捏力均大于非利手（P〈0.01）。3种捏力类型之间明显相关（r=0.568～0.707,P〈0.01）。女性在3种捏力类型下捏力大小均与体重密切相关（r=0.764～0.807,P〈0.001）。年龄、身高、掌厚与男性及女性在3种捏力类型下的捏力均无相关性。结论性别和捏力类型是影响捏力的主要因素,人体测量资料与捏力之间相关性尚不明确,需进一步研究。     

Benchmarks of Significant Change After Aphasia Rehabilitation

ObjectiveTo establish benchmarks of significant change for aphasia rehabilitation outcome measures (ie, Western Aphasia Battery-Aphasia Quotient [WAB-AQ], Communicative Effectiveness Index [CETI], Boston Naming Test [BNT]) and assess if those benchmarks significantly differ across subgroups (ie, time post onset, dose frequency, treatment type).Data SourcesA comprehensive literature search of 12 databases, reference lists of previous reviews, and evidence-based practice materials was conducted.Study SelectionRandomized controlled trials, quasi-experimental studies, single-subject design, and case studies that used a standardized outcome measure to assess change were included. Titles and full-text articles were screened using a dual review process. Seventy-eight studies met criteria for inclusion.Data ExtractionData were extracted independently, and 25% of extractions were checked for reliability. All included studies were assigned quality indicator ratings and an evidence level.Data SynthesisRandom-effects meta-analyses were conducted separately for each study design group (ie, within-/between-group comparisons). For within-group designs, the summary effect size after aphasia rehabilitation was 5.03 points (95% confidence interval, 3.95-6.10, P<.001) on the WAB-AQ, 10.37 points (6.08-14.66, P<.001) on the CETI, and 3.30 points (2.43-4.18, P<.001) on the BNT. For between-group designs, the summary effect size was 5.05 points (1.64-8.46, P=.004) on the WAB-AQ and 0.55 points (-1.33 to 2.43, P=.564) on the BNT, the latter of which was not significant. Subgroup analyses for the within-group designs showed no significant differences in the summary effect size as a function of dose frequency or treatment type.ConclusionsThis study established benchmarks of significant change on 3 standardized outcome measures used in aphasia rehabilitation.     

高强度聚焦超声辐照离体心肌组织的实验研究——局部心肌凝固剂量与温度的关系

目的　探讨在不同剂量的高强度聚焦超声 (high intensityfocusedultrasound ,HIFU )辐照下 ,正常猪离体心肌组织焦点局部的温度变化及规律。方法　应用不同声强度 (110 0 0W /cm2 、15 80 0W /cm2和 2 2 2 0 0W /cm2 )、不同辐照时间 (1s、3s、5s、7s、10s、13s和 15s)的HIFU连续定点辐照猪离体心肌组织的不同部位 ,同时通过置于焦点中心的热电耦温度计连续测温 ,观察焦域的温度变化。结果　不同剂量下焦点中心所达到的最高温度分布范围为 (66.4± 11.2 )℃～ (85 .8± 7.4)℃。不同处理因素间的最高温度差异具有显著性意义 (P <0 .0 5 ) ,停止辐照后焦点的降温曲线下降趋势由快到慢。结论　不同剂量的HIFU均可使焦点中心达到组织发生不可逆变化所需的温度 ,HIFU剂量与焦域中心温度有关 ,但不呈正比     

An Automatic Microcomputer System for Analysis of Monophasic Action Potentials

A computer system for rapid measurement and analysis of monophasic action potentials (MAPs) recorded in vivo was developed. MAPs recorded from the epicardium of mongrel dogs using a contact electrode were digitized by analog-to-digital conversion at a sampling rate of 1 kHz per channel for computer data acquisition. Activation time was detected using a sliding 10-point window at the location where the average positive dV/dT exceeds an adjustable threshold value in order to eliminate spurious detection due to baseline variability or motion artifact. Action potential duration (APD) was determined at 50% and 90% (APD50, APD90) repolarization levels at the first sample point below these detection levels. In addition, a tangent algorithm (APDtan) that detects peak negative dV/dT during repolarization was developed. APDtan was determined from the location of onset of activation to the intersection of tangent and baseline. APDtan allowed estimation of APD in the presence of subsequent premature beats when APD90 was not measurable. To validate activation time measurements, 4,600 action potentials were analyzed during fixed rate pacing. Over a range of paced coupling intervals from 200 to 1000 msec, an R2 value of 0.99968 and a slope of 0.9959 were obtained by linear regression between paced and calculated intervals. To validate APD measurements, 5035 action potentials were analyzed in five animals during fixed rate pacing (longer than 3 minutes) when action potential duration should be constant. Average coefficient of variation of 1.25%, 1.65%, and 1.14% were obtained for APD50, APD90, and APDtan, respectively. This algorithm provides a rapid and accurate method to analyze MAP activation and duration for basic physiological studies such as the determination of initiation of arrhythmias.     

The effect of cuff pressure deflation rate on accuracy in indirect measurement of blood pressure with the auscultatory method

The importance of cuff deflation rate in the auscultatory method of measuring blood pressure was investigated using a computer-based model. To determine the relationship between the cuff deflation rate and the measurement error, two cuff deflation protocols were used, one based on heart rate (mm Hg per heartbeat), the other on a constant rate (mm Hg per second). The different deflation protocols and rates were tested using a constant blood pressure of 120/80 mm Hg and heart rates ranging from 40 to 120 beats/min. It was confirmed that a cuff deflation rate that is time based will introduce larger errors at low heart rates. Using heart rate as a basis for cuff deflation rate yields a constant error that is independent of heart rate. The currently used standard of 3 mm Hg/s could result in a maximum error of 2.5 mm Hg in both systolic and diastolic pressures at a heart rate of 72 beats/min. The maximum systolic and diastolic errors increase to more than 4 mm Hg at 40 beats/min. A deflation rate of 2 mm Hg/beat, however, yields a maximum error of 2 mm Hg for both systolic and diastolic pressures, independent of heart rate. A cuff deflation rate based on heart rate is recommended to help minimize changes in measurement error when measuring blood pressure if a wide range of heart rates will be encountered.Supported by grants from IVAC, San Diego, CA, and Physio Control, Redmond, WA.     

Critique of the Dornier HM3 lithotripter as a clinical algesimeter

The power and nociceptive intensity of shock waves generated by the Dornier HM3 extracorporeal shock wave lithotripter (ESWL) are voltage dependent and suited to algesimetry in a controllable voltage range of 8–30 kV. Fidelity of the HM3 as an algesimeter was tested by:

1. (1) In vitro measurements of shock pressure at voltages between 14 and 30 kV were recorded by a force transducer at the point of clinical focus.

2. (2) Unanaesthetized volunteer (n = 5) assessment and VAS pain scores of shocks in the range of 10–24 kV, yielding highly significant correlations between blinded randomized shock voltage (r = 0.88), and VAS scores (r = 0.84).

3. (3) Voltage-tolerance curves generated from 33 ASA class 1 or 2 patients undergoing ESWL treatment under epidural analgesia with 0.125% bupivacaine, fortified with a bolus epidural dose of 100 μg fentanyl if pain arose during treatment. Voltage tolerance was increased by 50% after an epidural bolus of 100 μg fentanyl (P < 0.001). The respiratory consequences of epidural fentanyl were assessed by changes of respiratory rate and rhythm recorded from capnographic tracings of expired carbon dioxide.

This study indicates that the Dornier HM3 system provides a valuable opportunity to conduct precise, quantitative measurements of induced deep truncal pain, as well as the effectiveness and respiratory cost of analgesic interventions directly applicable to the safe management of acute pain.