Objective To explore the variation of E-index and M-index of rabbits with acute pulmonary embolism (APE) under the status of pulmonary hypertension (PHT). Methods Rabbit models of APE with PHT were established. A series of parameters [including peak early diastolic mitral inflow velocity (EM), peak late diastolic mitral inflow velocity (AM) and so on] were obtained with routine echocardiography and tissue Doppler imaging (TDI);and then E-index, M-index were calculated. The parameters before and after APE were compared. Results Twenty-three rabbit models with APE were successfully established, but 3 with atrial fibrillation were excluded. After APE, pulmonary artery pressure increased significantly, EM decreased observably, whereas right ventricular myocardial performance index (RVMPI) increased more evidently than left ventricular myocardial performance index (LVMPI) (P<0.01) did and E-index decreased and M-index increased remarkably. Conclusion Changes of E-index and M-index may provide reference for quantitative assessment of early APE.

Objective To evaluate diagnostic value of mitral regurgitation jet volume(MRvol) in the quantification of mitral regurgitation severity by general imaging three-dimensional quantification (GI3DQ) using the guideline recommended 2D integrative method as a reference.Methods Ninety-three patients with MR were divided into central MR group(n =41) and eccentric MR group(n =52).The American Society of Echocardiography (ASE)-recommended 2D integrative method was used as a reference for MR grading and MRvol was directly measured by GI3DQ method.Results In central MR,as assessed by receiver operating characteristic (ROC) analysis,the area under the curve(AUC)was 0.87(P <0.0001), and MRvol by GI3DQ at a cutoff value of 16.2 ml yielded 96.2% of sensitivity and 63.6% of specificity to differentiate mild from moderate MR;the AUC was 0.98(P < 0.0001),and a cutoff value of 47.8 ml yielded 98.6% of sensitivity and 96.2% of specificity to differentiate moderate from severe MR. In eccentric MR,the AUC was 0.76(P =0.086),and MRvol at a cutoff value of 14.8 ml yielded 90.9% of sensitivity and 60.0% of specificity to differentiate mild from moderate MR;the AUC was 0.84(P <0.0001) and a cutoff value of 40.7 ml yielded 80.0% of sensitivity and 79.7% of specificity to differentiate moderate from severe MR.Conclusions MRvol measured directly by GI3DQ could more exactly evaluate MR severity,and have better sensitivity and specificity to differentiate moderate from severe MR in central MR.

Objective Toinvestigatetheexpressionofsuppressorofcytokinesignaling1(SOCS1)inoverloaded ventricle papillary muscle, so as to understand its expression characteristics in structural remodeling after the overloading and the biomechanical properties of the muscle under cubic jellyfish toxin-1(CfTX-1) pretreatment that can affect cell signal transduction. Methods Abdominal aortic-venous fistula (AVF) were operated in Kunming mice (n=5), and the cardiac left ventricles were harvested after two weeks of fistulation. The mice in normal group were sham operated as a control (n=5). In vitro culture, the left ventricular papillary muscle of normal mice was used (n=20). In the stretching group, the isolated papillary muscles were double-ratio stretched and fixed on silicone plate. In the relaxation group, the muscles were not stretched. A separated subgroup that transfected with SOCS1 plasmids were set in each group of stretching and relaxation. The papillary muscle samples of each group were cultured in culture medium for 3 days at 37 ℃, and then homogenized for extracting total protein. The total protein was separated by 10％ sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The 23 ku band with SOCS1 was used as the target band, and the integrated optical density (IOD) value was measured by computer image analysis method. The expression of SOCS1 protein was detected by Western Blot and the imprinted IOD value was also measured. The papillary muscle in the stretching group was stretched by micro-positioned stretching method, and the initial load was 1 g. After stabilization, the papillary muscle was stretched by 15 mm for continuously 5 times, and the passive tension characteristic curves during the first and fifth stretching were observed and recorded. The peak passive tension (PTmax) and its deceleration velocity (DV) of the papillary muscle were calculated based on the curves. Results Comparing with the AVF group, the normal group had higher IOD values of 23 ku band and SOCS1 blot in total protein of the papillary muscle, and the differences were statistically significant (all P<0.01). The IOD value of 23 ku band in the SOCS1 transfected stretching group was significantly higher than those of the two relaxation groups, and the differences were statistically significant (all P<0.01). However, the difference of this value was not statistically significant between the two relaxation groups. The average IOD value of SOCS1 blot in the SOCS1 transfected stretching group was higher than those of the normal stretching group and the SOCS1 transfected relaxation group, and the differences were statistically significant (all P<0.01). Comparing with the normal group, the AVF group had higher PTmax and ultimate PTmax of the papillary muscles, and had a lower DV values, and the differences were statistically significant (all P<0.01). Conclusions The expression of SOCS1 is sensitive to tension load, and has a positive effect as an overload-sensitive signal in improving myocardial adaptability, protecting myocardial structure and maintaining systolic and diastolic function. CfTX-1 also has a positive effect on improving the compliance of ventricular papillary muscles.

Birth cohort is an effective method to explore the relationship between various prepregnant and pregnant exposures and the health of fetuses, infants and young children. It is a long construction period to build a birth cohort and the quality of research may be affected by many factors. This paper reviews the quality assurance and quality control measures in the process of China National Birth Cohort (CNBC), and summarizes the construction experience. We aim to provide experience for related cohort studies, which could improve the quality of cohort studies through removing the impact of related factors. CNBC adopted a series of measures to ensure the quality of research in the top-level design of quality assurance, including screening research center, developing member management system, formulating standard operating procedures and training staff by it. In terms of quality control, it includes real-time, timely and timing quality control for the process of data generation, full-cycle quality control for biological sample collection, processing, storage and comprehensive three-dimensional quality control for staff training, supervision and quantitative assessment.

The importance of gut microbes to human health has gradually attracted attention. With the use of animal models, it has been revealed that maternal microbes during pregnancy could influence their children's health outcomes through shaping their microbial composition and regulating the development of their metabolic and immune system. However, the physiological mechanism of the human body is more complex and is affected by the interaction of multiple factors. The research results obtained from animal models are often inconsistent with human studies. At present, the influence of maternal intestinal microbes during pregnancy on the microbial colonization in their offspring and on a series of children's health outcomes is still unclear. Establishing a sub-cohort to detect the microbiome of the women across pregnancy and of their offspring, and further to integrate with variety of environmental and behavioral exposures can better provide reliable support for the research on the mechanism of children's health and diseases. This paper briefly introduces the research objectives, content, progress, strength and limitations of the sub-cohort study.

OBJECTIVE To study the effects of yunaconitine on myocardial injury in rats and its mechanism related to mitochondrial apoptosis pathway rats. METHODS Forty SD rats were divided into normal group （normal saline）， yunaconitine high-dose and low-dose groups（0.14， 0.09 mg/kg）and aconitine group （positive control， 0.88 mg/kg） by random number method， with 10 rats in each group. They were given relevant medicine intragastrically， once a day， for consecutive 7 days. The levels of lactate dehydrogenase （LDH）， creatine kinase （CK）， creatine kinase isoenzyme （CK-MB）， superoxide dismutase （SOD） and malondialdehyde （MDA） in serum as well as the level of reactive oxygen species （ROS） in myocardial tissue were detected. The pathomorphological changes of myocardium and ultrastructural changes of myocardial mitochondria were all observed. The apoptosis of cardiomyocytes was determined. The protein relative expressions of B-cell lymphoma-2 （Bcl-2）， Bcl-2 associated X protein （Bax）， caspase-9， cleaved-caspase-9， caspase-3 and cleaved-caspase-3 were determined in myocardium of rats. RESULTS Compared with normal group， the serum levels of LDH， CK， CK-MB and MDA， the apoptotic numbers of cardiomyocytes， the level of ROS and protein expression of caspase-3 in myocardium were increased significantly in yunaconitine high-dose and low- dose groups （P＜0.05 or P＜0.01）； serum level of SOD and Bcl-2/Bax ratio in myocardium were all decreased significantly （P＜ 0.01）； the protein relative expressions of caspase-9， cleaved-caspase-9， caspase-3 and cleaved-caspase-3 in myocardium were significantly increased in yunaconitine high-dose group （P＜0.05）； some pathomorphological changes were found in 2 groups， such as myocardial fiber disorder， mitochondrial swelling. CONCLUSIONS Yunacotine could cause myocardial injury in rats. Its mechanism might be related to destroying the integrity of cardiomyocyte membrane， causing oxidative stress of cardiomyocyte， and inducing the apoptosis of myocardial cells through mitochondrial pathway.

OBJECTIVE：To study the toxicity mechanism of yunacotine-induced arrhythmia in rats. METHODS ：Totally 32 rats were randomly divided by random number table method into normal control group ，yunacotine low-dose and high-dose groups （0.09，0.14 mg/kg），aconitine group （positive control ，0.88 mg/kg），with 8 rats in each group. Administration groups were given the corresponding drugs once a day ，and normal control group was given the constant volume of normal saline ，for consecutive 7 d. After last intragastric administration ，the changes of electrocardiogram （ECG） were observed. The contents of adenosine triphosphate（ATP）in myocardial tissue and Ca 2+ in myocardial cells ，the activities of Na +-K+-ATPase and Ca 2+-Mg2+-ATPase as well as the protein expression of ranolidine receptor 2（RyR2）and Ca 2+-ATPase（SERCA2）in myocardial tissue were determined. RESULTS：Compared with normal control group ，time limit of QRS wave and QTc intervals of rats were prolonged significantly in yunaconitine low-dose group （P＜0.01）. The content of Ca 2 + in myocardial cells ， the ATP contents ， the activities of Ca2+-Mg2+-ATPase and Na +-K+-ATPase as well as the protein expression of SERCA 2 in myocardial tissue were reduced significantly （P＜0.05 or P＜0.01）. The heart rate of rats in yunaconitine high-dose group and aconitine group were increased significantly （P＜ 0.05 or P＜0.01），and time limit of QRS wave and QTc intervals were significantly prolonged （P＜0.01）；the content of Ca 2+ in myocardial cells was increased significantly （P＜0.01）；ATP content ，the activities of Ca 2+-Mg2+-ATPase and Na +-K+-ATPase，and protein expression of RyR 2 and SERCA 2 in myocardial tissue were decreased significantly （P＜0.01）. CONCLUSIONS ： Yunaconitine can induce arrhythmia in rats ，the mechanism of which may be associated with Ca 2+ overload that resulted from reducing the activities of Na +-K+-ATPase and Ca 2+-Mg2+-ATPase and down-regulating the expression of related calcium transporter RyR2 and SERCA 2.

OBJECTIVE To investigate the antibacterial activities of flavaspidic acid BB against the main pathogens of skin and soft tissue infections such as methicillin -resistant Staphylococcus aureus （MRSA）and methicillin -sensitive Staphylococcus aureus （MSSA） in vitro and in vivo . METHODS Microdilution method was used to determine the minimum inhibitory concentration（MIC）and minimum bactericidal concentration （MBC）of flavaspidic acid BB on 10 strains of MRSA and 13 strains of MSSA ；time-kill curves of MRSA 11 and MSSA 23 strains were drawn by plate method ；the checkerboard dilution method was used to determine the combined antibacterial effect of flavaspidic acid BB and mupirocin ；the skin abscess model of mice was established to evaluate the antibacterial effects of 0.5%，1%，2% flavaspidic acid BB cream on MRSA 11 or MSSA 23 strains in vivo；scanning electron microscopy was used to observe the effects of flavaspidic acid BB on the morphology of MRSA 11 or MSSA23 strains. The contents of nucleic acid leakage and extracellular protein were also determined . RESULTS MIC and MBC ranges of flavaspidic acid BB against 10 strains of MRSA were 6.30-80.00 μg/mL and 40.00-640.00 μg/mL；MIC and MBC ranges of 13 strains of MSSA were 40.00-80.00 μg/mL and 63.50-126.99 μg/mL，respectively. The bactericidal rate of MRSA 11 and MSSA23 strains were 99.9% after interfered with plavaspidic acid BB for 36 h. The combination of flavaspidic acid BB and mupirocin showed an additive effect on MRSA strain and an additive or synergistic effect on MSSA strain . The 0.5%，1% and 2% flavaspidic acid BB cream could reduce the volume of abscess and the bacterial load of skin abscess model mice to some extent （P＜0.05），and improved the pathological changes of skin inflammation in skin abscess site of mice . Flavaspidic acid BB could make MRSA 11 and MSSA 23 cells shrinkage and rupture ，and significantly increase the contents of nucleic acid leakage and extracellular protein （P＜0.01）. CONCLUSIONS Flavaspidicacid BB shows good antibacterial effect on MRSA and MSSAE-mail：tchp66@163.com in vitro and in vivo ，the mechanism of which may be related to the change of membrane permeability .