Electrophysiological identification of human induced pluripotent stem cell-derived cardiomyocytes / 生理学报

The present study was aimed to characterize the electrophysiology of human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs). IMR90-4 cells were induced to differentiate into cardiomyocytes by temporal modulation of regulators of canonical Wnt signaling. The protein expression of cardiac troponin T (cTnT) was detected by immunofluorescence staining and flow cytometry, and the differentiation rate of hiPSC-CMs was calculated. The action potentials (APs) of hiPSC-CMs were recorded by patch clamp and used to classify different types of cardiomyocytes. The electrophysiological characteristics of hiPSC-CMs were further analyzed. The results showed that the cTnT positive rate of hiPSC-CMs was above 95%. hiPSC-CMs were differentiated into 3 types of cardiomyocytes based on the properties of AP: ventricular-, atrial- and nodal-like cells. In comparison with the other two types of cells, the APs of ventricular-like cells exhibited longer duration, higher amplitude and higher dV/dt. The nodal-like cells had the lowest dV/dt among all the three types. These results indicate that hiPSC can be differentiated into the cardiomyocytes with high purity and the differentiated hiPSC-CMs have similar electrophysiological characteristics to adult cardiomyocytes.

Risk factors for adult death due to 2009 pandemic influenza A (H1N1) virus infection: a 2151 severe and critical cases analysis / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>The 2009 pandemic H1N1 (pH1N1) influenza showed that relatively young adults accounted for the highest rates of hospital admission and death. In preparation for pH1N1, the aim of the study is to identify factors associated with the mortality of patients with 2009 pH1N1 infection, especially for young patients without chronic medical conditions.</p><p><b>METHODS</b>Retrospective observational study of 2151 severe or critical adult cases (≥ 14 years old) admitted to a hospital with pH1N1 influenza from September 1, 2009 to December 31, 2009 from 426 hospitals of 27 Chinese provinces. A confirmed case was a person whose pH1N1 virus infection was verified by real-time reverse-transcriptase polymerase chain reaction (rRT-PCR). Severe and critical cases were defined according to the H1N1 2009 Clinical guidelines (Third Edition, 2009) released by the Ministry of Health of China.</p><p><b>RESULTS</b>Among the 2151 patients, the mean age was 34.0 years. Two hundred and ninty-three (13.6%) died during hospital stay. One thousand four hundred and forty-two patients (67.0%) had no comorbidities and 189 (13.1%) of them died. Pregnancy (OR 8.03), pneumonia (OR 8.91), dyspnea (OR 3.95), central nervous system (CNS) symptom (OR 1.55), higher APACHE (Acute Physiology and Chronic Health Evaluation) II score (OR 1.06), Alanine aminotransferase (ALT) (OR 1.002), and the lactate dehydrogenase (LDH) level (OR 1.001) were independent risk factors for death among adults without chronic medical conditions. Higher APACHE II score (OR 1.08) and age (OR 1.06) were independent risk factors for death among adults with respiratory diseases. A multivariate analysis showed an association between mortality and CNS symptoms (OR 2.66), higher APACHE II score (OR 1.03), ALT (OR 1.006), and LDH level (OR 1.002) in patients with cardiovascular diseases. Dyspnea (OR 11.32) was an independent risk factor for patient death in patients with diabetes mellitus.</p><p><b>CONCLUSION</b>Clinical knowledge of identified prognostic factors for mortality may aid in the management of adult influenza infection.</p>

Clinicopathological analysis of 141 pediatric autopsy cases / 中华儿科杂志

<p><b>OBJECTIVE</b>To summarize the major pathological findings, causes of deaths and reasons for misdiagnosis of 141 autopsy cases and thereby to improve the diagnosis level and reduce misdiagnosis.</p><p><b>METHOD</b>A retrospective analysis of pathological reports and clinical materials of 141 pediatric autopsy cases from June, 1986 to June, 2006 of our department was performed. Classification was based on (1) international classification of diseases of the World Health Organization; (2) age: cases 28 d-3 years old were defined as infants and young children group, -7 yeas olds were defined as preschool age group, -14 years olds were school age group; (3) when statistics was conducted, the first 3 items of the clinical diagnoses were counted. If one of them was consistent with the pathological diagnosis, it was regarded as basically in accordance with the pathology, if none of the first 3 was consistent with pathological diagnosis, the case was regarded as misdiagnosed.</p><p><b>RESULTS</b>(1) The top three major pathological diagnosis and causes of death were: 1) Classified according to system: 41 cases had tumor (29.1%), 25 cases had respiratory diseases (17.7%), 18 cases had infectious diseases (12.7%); 2) Classified according to disease: 18 cases had malignant histiocytosis, 12 cases had sepsis, 11 cases had lobular pneumonia. (2) The causes of deaths changed gradually. The top cause of death was respiratory diseases during the former 10 years and was tumor during the latter 10 years; the materials showed that 95 cases were 28 d-3 years old (67.4%), and some rare diseases, such as mediastinal and lung chorionic epithelioma (choriocarcinoma), and pulmonary alveolar proteinosis were found. (3) In 90 cases the clinical diagnosis was basically in accordance with the pathological diagnosis (63.8%) and misdiagnosis was found in 51 cases (36.2%).</p><p><b>CONCLUSION</b>For clinical diagnosis of critically ill patients, both common and rare diseases should be considered. Analysis of autopsy materials could confirm and/or correct clinical diagnosis and is helpful to summarize clinical diagnosis experience.</p>

A pilot study on the proteome of cerebrospinal fluid of Staphylococcus epidermidis meningitis in children / 中国当代儿科杂志

<p><b>OBJECTIVE</b>Bacterial meningitis is a kind of central nervous system infection with a high incidence, disability and fatality in children. Prompt diagnosis and treatment are associated with an improved prognosis. Low positive rate of bacterial cultures of the cerebrospinal fluid (CSF) makes it difficult to make a definite diagnosis. This experiment aimed to investigate a proteome profile of normal CSF of Chinese children by two-dimensional polyacrydamide gel electrophoresis (2-DE), and to sieve the disease-specific proteins of Staphylococcus epidermidis meningitis (SeM) to provide basis for early diagnosis and treatment of SeM.</p><p><b>METHODS</b>Four mL CSF samples were obtained respectively from SeM and normal children. The separated proteins with immobile pH gradient (IPG) 2-DE technology and protein spots were visualized by Coomassie Brilliant Blue staining. The stained 2-DE gels were scanned on the Imagescanner and pictures were obtained through Labscan software. The images were analyzed with PDQuest software and the differences of protein spots were compared between the SeM and normal children.</p><p><b>RESULTS</b>Mean protein spots of the 2-DE gels were 438 and 425 in the SeM and normal groups respectively. Twenty-five protein spots only occurred in normal CSF and 12 spots only occurred in the SeM group. The expression of 6 protein spots showed up-regulation and that of 19 showed down-regulation in the SeM group compared with that in the normal group.</p><p><b>CONCLUSIONS</b>A 2-DE profile of CSF proteome was successfully established in SeM and normal children through proteomic technique. By the differentiated analysis of these CSF 2-DE gels, the differences of CSF proteome profiles were found between SeM and normal children. Future analysis and identification of these spots will contribute to find out the disease specific proteins of SeM and to provide basis for early diagnosis and therapy of this disorder.</p>

Influence of Tumor Necrosis Factor-? on Blood Brain Barrier Permeability and Its Mechanism / 实用儿科临床杂志

Objective To understand the changes and possible mechanism of the blood brain barrier(BBB) permeability induced by tumor necrosis factor(TNF-?) in vitro.Methods BBB model was established by coculturing allogenic brain microvessel end othelial cell(BMEC) and astrocyte(AS).The BBB model was divided randomly into normal control group,TNF-? group and Y-27632 pretreatment group.The changes of BBB permeability were evaluated by Gamma radioim muno assay counter.Results The Gamma radioimmuno assay indicated that the marker,~(125)I-BSA,across the BBB model in vitro was significantly increased after TNF-? treatment compared with control group,Y-27632 pretreatmen could prevent the permeability of BBB induced by TNF-?(P