鱼纲动物孔鳐血红蛋白自身不相互作用的研究及其进化意义

目的:研究一种软骨鱼系动物(孔鳐)自身血红蛋白成份的相互作用.方法:淀粉-琼脂糖混合凝胶交叉电泳.结果:孔鳐自身血红蛋白成份不相互作用.结论:本实验完善了研究室所作的"各种脊椎动物血红蛋白自身相互作用的系列研究".同前面所进行的各种脊椎动物血红蛋白分别与人血红蛋白、胎儿血红蛋白相互作用的研究对照比较,进一步验证脊椎动物血红蛋白与各种蛋白分子在电场中的相互作用的分水岭可能位于爬行纲动物,丰富了血红蛋白分子进化理论.     

Co-exposure to silver nanoparticles and cadmium induce metabolic adaptation in HepG2 cells

Although multiple studies have reported the toxicological effects and underlying mechanisms of toxicity of silver nanoparticles (AgNP) in a variety of organisms, the interactions of AgNP with environmental contaminants such as cadmium are poorly understood. We used biochemical assays and mass spectrometry-based proteomics to assess the cellular and molecular effects induced by a co-exposure of HepG2 cells to AgNP and cadmium. Cell viability and energy homeostasis were slightly affected after a 4-h exposure to AgNP, cadmium, or a combination of the two; these endpoints were substantially altered after a 24-h co-exposure to AgNP and cadmium, while exposure to one of the two contaminants led only to minor changes. Proteomics analysis followed the same trend: while a 4-h exposure induced minor protein deregulation, a 24-h exposure to a combination of AgNP and cadmium deregulated 43% of the proteome. The toxicity induced by a combined exposure to AgNP and cadmium involved (1) inactivation of Nrf2, resulting in downregulation of antioxidant defense and proteasome-related proteins, (2) metabolic adaptation and ADP/ATP imbalance, and (3) increased protein synthesis possibly to reestablish homeostasis. The adaptation strategy was not sufficient to restore ADP/ATP homeostasis and to avoid cell death.     

牙龈卟啉单胞菌FtsZ的C末端在FtsZ-FtsA相互作用中起着关键作用

目的：探讨牙龈卟啉单胞菌FtsZ与FtsA之间相互作用的功能区域。方法：通过缺失诱变法构建了C末端缺失变异型的PgFtsZ(ZΔC01，ZΔC02，ZΔC03)，并表达和纯化了这些蛋白质，同时进一步通过免疫印迹法来鉴定这些C末端缺失变异型的PgFtsZ。然后，通过overlay assay法，以牛血清白蛋白为阴性对照，检测了这些C末端缺失变异型及野生型PgFtsZ和PgFtsA相互作用的特性。结果：野生型PgFtsZ与PgFtsA表现出极强的结合特性，然而去除C末端的73个氨基酸残基的ZΔC01，则表现出极弱的结合特性，或者当进一步去除C末端的128和177个氨基酸残基的ZΔC02和ZΔC03，同ZΔC01一样也表现出与PgFtsA极弱的结合特性。结论：PgFtsZ和PgFtsA相互作用的功能区域位于PgFtsZ的C末端。     

基于雨课堂的课前预习和课堂互动在语言治疗学课程教学中的应用

目的探讨基于雨课堂的课前预习和课堂互动在语言治疗学课程教学中的应用效果。方法本研究采用因素分析法。2019年9月至12月,选取中国医科大学2017级四年制康复治疗学专业55名学生为研究对象,在语言治疗学课程教学中采用雨课堂教学方式进行课前预习和课堂互动,通过期末考试总成绩评价教学效果,分析课前预习和课堂互动对期末总成绩的影响,并对相关数据进行卡方检验和回归分析。结果课前预习课件页数为优秀和预习题应答为优秀的学生,其期末考试总成绩优秀的比例[分别为71.4%(20/28),70.0%(21/29)]高于课前预习课件为良好和预习题应答为良好[分别为28.6%(8/28),30.0%(9/30)]的学生(P<0.01)。课堂思考题应答为优秀和良好的学生,其期末总成绩优秀的比例[分别为58.3%(14/24),41.7%(10/24)]的差异无统计学意义(P=0.28)。预习课件页数[OR(95%CI)=4.76(1.21~18.64),P=0.03]和预习题应答分数[OR(95%CI)=6.46(1.32~31.72),P=0.02]是影响期末总成绩的重要因素。结论基于雨课堂的课前预习有利于提高学生期末考试总成绩,提高语言治疗学课程学习效果;基于雨课堂的课堂互动的应用效果还需进一步探索。     

Predicting severity of pathological scarring due to burn injuries: a clinical decision making tool using Bayesian networks

It is important for clinicians to understand which are the clinical signs, the patient characteristics and the procedures that are related with the occurrence of hypertrophic burn scars in order to carry out a possible prognostic assessment. Providing clinicians with an easy‐to‐ use tool for predicting the risk of pathological scars. A total of 703 patients with 2440 anatomical burn sites who were admitted to the Department of Plastic and Reconstructive Surgery, Burn Center of the Traumatological Hospital in Torino between January 1994 and May 2006 were included in the analysis. A Bayesian network (BN) model was implemented. The probability of developing a hypertrophic scar was evaluated on a number of scenarios. The error rate of the BN model was assessed internally and it was equal to 24·83%. While classical statistical method as logistic models can infer only which variables are related to the final outcome, the BN approach displays a set of relationships between the final outcome (scar type) and the explanatory covariates (patient's age and gender, burn surface area, full‐thickness burn surface area, burn anatomical area and wound‐healing time; burn treatment options such as advanced dressings, type of surgical approach, number of surgical procedures, type of skin graft, excision and coverage timing). A web‐based interface to handle the BN model was developed on the website www.pubchild.org (burns header). Clinicians who registered at the website could submit their data in order to get from the BN model the predicted probability of observing a pathological scar type.     

Acute ventilatory restriction in children after weaning off inhaled nitric oxide: relation to rebound pulmonary hypertension

Objective: To assess the interaction between pulmonary hemodynamics and respiratory mechanics during acute pulmonary hypertension. Patients: Ventilated and paralysed children treated with inhaled nitric oxide because of post-operative pulmonary hypertension. Interventions: Weaning of inhaled nitric oxide. Measurements: Air flow and airway pressure, calculation of dynamic respiratory system compliance and respiratory system resistance for each breath by multiple linear regression. Results: In four patients, increases in pulmonary arterial pressure from 26.1 to 56.7 mmg (p < 0.001) during weaning off nitric oxide were associated with decreases in tidal volume (from 9.7 → 8.2 ml/kg, p < 0.01) and reductions in dynamic respiratory system compliance (from 0.52 → 0.34 cmH₂0/ml/kg, p < 0.001), while respiratory system resistance was unchanged. Conclusions: Impaired ventilation during acute pulmonary hypertension is predominantly related to a reduction in respiratory system compliance. Received: 26 March 1998 Final revision received: 9 June 1998 Accepted: 30 July 1998     

偎脓长肉理论指导下药疮交互作用机制探讨

偎脓长肉是中医治疗疮面的特色外治理论之一。邪腐已去应用生肌类药物外敷疮面促使"脓"生,可保护疮面、促进愈合。中药偎出之脓属"津液"范畴,在药偎脓生过程中药物和疮面充分作用,药物有效成分主动促进疮面发生一系列的微环境改变。药物作用于疮面后,疮面产生脓,使得药物与疮面形成了温度、湿度适宜的微环境,有利于药物有效成分的释放及疮面对药物有效成分的主动摄取,并可能通过脓的化生作用改变药物性质,共同作用促进疮面主动愈合。     

缺血性脑卒中全基因组关联研究提示阳性基因位点与睡眠行为的交互作用

目的: 探讨睡眠行为(睡眠时长、睡眠效率、入睡时间)和全基因组关联研究(genome-wide association studies, GWAS)提示阳性缺血性脑卒中(ischemic stroke, IS)基因位点与IS风险的关联,以及睡眠-基因交互作用与IS风险的关联。方法: 基于北京市房山家系队列,在基线对所有研究对象进行问卷调查、体格检查、血生化检测和基因型检测。采用多因素广义线性模型分析睡眠、基因与IS的关联。结果: 共纳入研究对象4 648人,平均年龄(58.5±8.7)岁,其中IS患者有1 316人。相比于非患者,IS患者睡眠时长≥9 h、睡眠效率 < 80%及入睡时间早于22:00占比更高(P均 < 0.05)。多因素广义线性模型下,未见睡眠时长与IS风险的线性关联(OR=1.04,95%CI：0.99~1.10,P=0.085)。睡眠效率与IS风险呈线性负相关(OR=0.18,95%CI：0.06~0.53,P=0.002);相比于睡眠效率≥80%,睡眠效率 < 80%的IS风险为其1.47倍(95%CI：1.03~2.10,P=0.033)。相较于在22:00—22:59入睡,入睡时间早于22:00的IS风险是其1.26倍(95%CI：1.04~1.52,P=0.017)。多因素模型发现ABO基因上rs579459位点与入睡时间存在交互作用(P_交互=0.040),rs579459致病等位基因T个数为2时,相比于入睡时间22:00—22:59,早于22:00入睡者IS风险显著升高,为其1.56倍(95%CI：1.20~2.04,P=0.001),而致病等位基因个数为0或1时无显著关联。仅调整性别、年龄、家系的模型中,睡眠时长与PITX2基因上rs2634074致病等位基因T的个数对IS存在交互作用(P_交互=0.033)。结论: 睡眠效率降低与IS风险增高有关,入睡时间早于22:00与较高的IS风险相关。入睡时间与ABO基因上rs579459和IS风险存在交互作用;睡眠时长与PITX2基因上rs2634074和IS风险可能存在潜在的交互作用。