Physical Activity,Gender Difference,and Depressive Symptoms

Objective

To investigate the roles of physical activity (exercise) and sociodemographic factors in depressive symptoms among men and women in the United States.

Data Source

2011 U.S. Behavioral Risk Factor Surveillance System (BRFSS).

Study Design

Patient Health Questionnaire Depression Scale (PHQ-8) scores are aggregated and divided into five categories. An ordered switching probability model with binary endogenous physical activity is developed to accommodate ordinality of depression categories and ameliorate statistical biases due to endogeneity of physical activity.

Principal Findings

Average treatment effects suggest physical activity ameliorates depressive symptoms among mildly and moderately depressed individuals, most notably among mildly depressed women. Gender differences exist in the roles of sociodemographic factors, with age, income, race, education, employment status, and recent mental health condition playing differentiated roles in affecting depressive symptoms.

Conclusions

Regular physical activity reduces depressive symptoms among both men and women with mild to moderate depression, notably among women.     

命门学说复杂性科学机理探析之二--命门学说与混沌学

人的生命是一个复杂的自组织系统,对于自然界来说既具有相对的独立性,又是一个开放的巨系统。当人的意识状态与自然之道的无极化统一场势性质相接近、相同一的时候,亦即达到“天人合一”状态时,人的生命自组织状态会处于一种最佳的状态,实现生命活动的自组织、自调整、自修复、自稳态,使生命系统与大自然逐步达到最大的统一与和谐,而这种意识状态就是恬淡虚无、知而不辨、混混沌沌、无思无虑的状态。《庄子》把这一修道以养生的过程称之为“修混沌术”。中医命门学说是传统修道养生理论与中医理论相结合的产物,与混沌学原理相通相契。对命门学说与混沌学内在关系的深刻揭示,不仅对现代人养生康复、延年益寿有重要意义,而且对现代科学的进一步发展也有重要的启示。     

Long-Term Outcomes After PCI or CABG for Left Main Coronary Artery Disease According to Lesion Location

ObjectivesThe aim of this study was to investigate the impact of lesion site (ostial or shaft vs. distal bifurcation) on long-term outcomes after percutaneous coronary intervention (PCI) or coronary artery bypass grafting (CABG) for left main coronary artery (LMCA) disease.BackgroundLong-term comparative data after PCI and CABG for LMCA disease according to lesion site are limited.MethodsPatients from the MAIN-COMPARE (Revascularization for Unprotected Left Main Coronary Artery Stenosis: Comparison of Percutaneous Coronary Angioplasty Versus Surgical Revascularization) registry were analyzed, comparing adverse outcomes (all-cause mortality [a composite outcome of death, Q-wave myocardial infarction, or stroke] and target vessel revascularization) between PCI and CABG according to LMCA lesion location during a median follow-up period of 12.0 years.ResultsIn overall population, the adjusted risks for death and serious composite outcome were higher after PCI than after CABG for distal bifurcation disease, which was mainly separated beyond 5 years. These outcomes were not different for ostial or shaft disease. When comparing drug-eluting stents (DES) and CABG, the adjusted risks for death and serious composite outcome progressively diverged beyond 5 years after DES compared with CABG for distal bifurcation disease (death: hazard ratio: 1.78; 95% confidence interval: 1.22 to 2.59; composite outcome: hazard ratio: 1.94; 95% confidence interval: 1.35 to 2.79). This difference was driven mainly by PCI with a 2-stent technique for distal bifurcation. In contrast, the adjusted risks for these outcomes were similar between DES and CABG for ostial or shaft disease.ConclusionsAmong patients with distal LMCA bifurcation disease, CABG showed lower mortality and serious composite outcome rates compared with DES beyond 5 years. However, there were no between-group differences in these outcomes among patients with ostial or shaft LMCA disease.     

Calibration of Multiple In Silico Tools for Predicting Pathogenicity of Mismatch Repair Gene Missense Substitutions

Classification of rare missense substitutions observed during genetic testing for patient management is a considerable problem in clinical genetics. The Bayesian integrated evaluation of unclassified variants is a solution originally developed for BRCA1/2. Here, we take a step toward an analogous system for the mismatch repair (MMR) genes (MLH1, MSH2, MSH6, and PMS2) that confer colon cancer susceptibility in Lynch syndrome by calibrating in silico tools to estimate prior probabilities of pathogenicity for MMR gene missense substitutions. A qualitative five‐class classification system was developed and applied to 143 MMR missense variants. This identified 74 missense substitutions suitable for calibration. These substitutions were scored using six different in silico tools (Align‐Grantham Variation Grantham Deviation, multivariate analysis of protein polymorphisms [MAPP], MutPred, PolyPhen‐2.1, Sorting Intolerant From Tolerant, and Xvar), using curated MMR multiple sequence alignments where possible. The output from each tool was calibrated by regression against the classifications of the 74 missense substitutions; these calibrated outputs are interpretable as prior probabilities of pathogenicity. MAPP was the most accurate tool and MAPP + PolyPhen‐2.1 provided the best‐combined model (R² = 0.62 and area under receiver operating characteristic = 0.93). The MAPP + PolyPhen‐2.1 output is sufficiently predictive to feed as a continuous variable into the quantitative Bayesian integrated evaluation for clinical classification of MMR gene missense substitutions.     

Fitting the Balding–Nichols model to forensic databases

Large forensic databases provide an opportunity to compare observed empirical rates of genotype matching with those expected under forensic genetic models. A number of researchers have taken advantage of this opportunity to validate some forensic genetic approaches, particularly to ensure that estimated rates of genotype matching between unrelated individuals are indeed slight overestimates of those observed. However, these studies have also revealed systematic error trends in genotype probability estimates. In this analysis, we investigate these error trends and show how they result from inappropriate implementation of the Balding–Nichols model in the context of database-wide matching. Specifically, we show that in addition to accounting for increased allelic matching between individuals with recent shared ancestry, studies must account for relatively decreased allelic matching between individuals with more ancient shared ancestry.     

Quantitative evaluation of the diagnostic thinking process in medical students

OBJECTIVE: To explore the diagnostic thinking process of medical students. SUBJECTS AND METHODS: Two hundred twenty-four medical students were presented with 3 clinical scenarios corresponding to high, low, and intermediate pre-test probability of coronary artery disease. Estimates of test characteristics of the exercise stress test, and pre-test and post-test probability for each scenario were elicited from the students (intuitive estimates) and from the literature (reference estimates). Post-test probabilities were calculated using Bayes' theorem based upon the intuitive estimates (Bayesian estimates of post-test probability) and upon the reference estimates (reference estimates of post-test probability). The differences between the reference estimates and the intuitive estimates, and between Bayesian estimates and the intuitive estimates were used for assessing knowledge of test characteristics, and ability of estimating pre-test and post-test probability of disease. RESULTS: Medical students could not rule out disease in low or intermediate pre-test probability settings, mainly because of poor pre-test estimates of disease probability. They were also easily confused by test results that differed from their anticipated results, probably because of their inaptitude in applying Bayes' theorem to real clinical situations. These diagnostic thinking patterns account for medical students or novice physicians repeating unnecessary examinations. CONCLUSIONS: Medical students' diagnostic ability may be enhanced by the following educational strategies: 1) emphasizing the importance of ruling out disease in clinical practice, 2) training in the estimation of pre-test disease probability based upon history and physical examination, and 3) incorporation of the Bayesian probabilistic thinking and its application to real clinical situations.     

Does Prior Abdominal Surgery Influence Conversion Rates and Outcomes of Laparoscopic Right Colectomy in Patients with Neoplasia?

Purpose  The study investigated the impact of prior abdominal surgery on conversions and outcomes of laparoscopic right colectomy. Methods  A consecutive series of 414 patients with cancer or adenomas who underwent a laparoscopic right colectomy from March 1996 to November 2006 were studied for surgical conversions and outcomes. Conversion was defined as an incision length > 7 cm. Results  Patients with prior abdominal surgery (n = 191) were compared with patients with no prior abdominal surgery (n = 223), and showed no significant differences in age, ASA classification, length of stay, operative time, blood loss, harvested nodes, tumor size, and specimen length. Significantly more wound infections occurred in the prior abdominal surgery group (22 vs.12, P = 0.023). Body mass index > 30 showed a three-fold increased risk of conversion. Fifteen percent of the no prior abdominal surgery patients and 17 percent of the prior abdominal surgery patients were converted (P > 0.05). Conversion was associated with a longer mean length of stay (8.8 days) relative to laparoscopically completed cases (6.3 days) regardless of prior abdominal surgery history (P < 0.0001). Conclusions  Laparoscopic right colectomy for neoplasia was not associated with a higher conversion rate or morbidity in patients with prior abdominal surgery. Prior abdominal surgery is not a contraindication to laparoscopic right colectomy. Presented at the 15th International Congress of the European Association of Endoscopic Surgery, Athens, Greece, July 4 to 7, 2007.     

High-resolution manometry and impedance-pH/manometry: valuable tools in clinical and investigational esophagology

Both high-resolution manometry (HRM) and impedance-pH/manometry monitoring have established themselves as research tools and both are now emerging in the clinical arena. Solid-state HRM capable of simultaneously monitoring the entire pressure profile from the pharynx to the stomach along with pressure topography plotting represents an evolution in esophageal manometry. Two strengths of HRM with pressure topography plots compared with conventional manometric recordings are (1) accurately delineating and tracking the movement of functionally defined contractile elements of the esophagus and its sphincters, and (2) easily distinguishing between luminal pressurization attributable to spastic contractions and that resultant from a trapped bolus in a dysfunctional esophagus. Making these distinctions objectifies the identification of achalasia, distal esophageal spasm, functional obstruction, and subtypes thereof. Ambulatory intraluminal impedance pH monitoring has opened our eyes to the trafficking of much more than acid reflux through the esophageal lumen. It is clear that acid reflux as identified by a conventional pH electrode represents only a subset of reflux events with many more reflux episodes being composed of less acidic and gaseous mixtures. This has prompted many investigations into the genesis of refractory reflux symptoms. However, with both technologies, the challenge has been to make sense of the vastly expanded datasets. At the very least, HRM is a major technological tweak on conventional manometry, and impedance pH monitoring yields information above and beyond that gained from conventional pH monitoring studies. Ultimately, however, both technologies will be strengthened as outcome studies evaluating their utilization become available.     

验前概率联合冠脉CT造影对于稳定型冠心病的诊断价值

目的：比较升级的Diamond-Forrester法(updated Diamond-Forrester method,UDFM)和Duke临床评分(Duke clinical score,DCS)对于冠心病的评估准确性,并进一步分析验前概率与冠脉CT造影(computed tomographic coronary angiography, CTCA)联合应用的诊断准确性。方法纳入2012年1月-2013年12月因稳定型心绞痛在解放军总医院心内科先后行CTCA和传统冠状动脉造影(conventional coronary angiography,CCA)的患者523例,分别用UDFM和DCS估算每例患者患冠心病的验前概率。以CCA结果为金标准,分析验前概率、CTCA及两者联合应用对冠心病的诊断准确性。理论验后概率根据贝叶斯公式进行计算。结果523例患者中有385例(74%)CCA结果为阳性。与UDFM相比,DCS将更多的CCA结果阳性患者分入高验前概率组(46%vs 23%,P＜0.0001)。DCS的ROC曲线下面积明显大于UDFM[0.77(0.73,0.82)vs 0.71(0.66,0.77),P=0.0009]。根据DCS估算结果划分的低、中和高3个验前概率亚组中,CTCA的敏感性、特异性、阳性预测值及阴性预测值分别是94%、98%和97%,94%、87%和55%,91%、94%和93%及96%、96%和77%。中验前概率亚组的理论验后概率十分接近实际验后概率(阳性：94.7%vs 93.6%,阴性：3.7%vs 4.0%)。结论对于稳定型心绞痛患者,DCS比UDFM更适用于冠心病验前概率的估算。将按DCS估算的验前概率与CTCA联合应用,能够有效提高CTCA的诊断准确性,并避免过度检查。