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Objective To investigate the structural distribution features and mechanism of elastic fibers and collagen fibers in ventricular interstitium of aged rats. Methods Five young SD rats (24 weeks) and five old SD rats (104 weeks) were used,and their cardiac function was examined by echocardiography. Modified Weigert elastic fiber staining, immunohistochemistry, immunofluorescence and Western blotting techniques were used to detect the expression changes of type I and IH collagen fibers and their proteins, elastic fibers and their proteins, matrix metalloproteinase 2 (MMP-2), matrix metalloproteinase 9 (MMP-9) and tissue inhibitor of metalloproteinase 2 (TIMP-2), respectively. Results The type I and type IH collagen in the ventricular interstitium of aged rats was very sufficient and wrapped around the cardiomyocytes. Compared with the young rats, the content of collagen protein in the ventricular interstitium of the aged rats significantly increased (P<0. 05). Elastic fibers in the ventricular interstitium of the aged rats were and widely distributed. Compared with the young rats, the number of elastic fibers and the level of elastin in the ventricular interstitium of the aged rats significantly decreased (P<0. 05), and the expression levels of MMP-2 and MMP-9 in ventricular muscle of aged rats increased, and the)' were correlated with the level of elastin. The level of TIMP-2 in ventricular muscle of aged rats decreased with age. Conclusion The number of collagen fibers and elastic fibers in ventricular interstitium of aged rats is fluctuated with each other. With the increase of age, the contents of TIMP-2 and elastic fibers in the ventricular interstitium gradually decreased, and the ratio of collagen fibers to elastic fibers is out of balance.
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Objective To investigate the expression of elastin and collagen in heart of rats with chronic heart failure and their related proteases. Methods Sprague-Dawley rat model of chronic heart failure was made by intraperitoneal injection of doxorubicin hydrochloride. Examination of cardiac function by echocardiography. ELISA and immunohistochemistry were used to detect brain natriuretic peptide ( BNP) , and Masson staining was used to detect myocardial fibrosis. The mRNA levels of elastin, I /IH collagen were detected by Real-time PCR and the expression levels of elastin, I/IH collagen, Matrix metalloproteinase (MMP)-2 and MMP-9 were detected by Western blotting. Results Compared with the control group, the heart function of rats in the model group decreased, the BNP content in serum increased, the expression of BNP in myocardial tissue was strongly positive, and the mRNA and protein expression of elastin decreased. Nevertheless, the mRNA and protein expression of I / IH collagen increased. At the same time, both MMP-2 and MMP-9 protein expression levels increased in model rat heart. Conclusion Heart failure leads to decreased expression of elastin, I /IH collagen expression increased, and the MMP-2 and MMP-9 may be involved in the regulation of this process.
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Objective To analyze the risk factors affecting pre-eclampsia, to establish a pre-eclampsia risk assessment model, and to assess the risk of pre-eclampsia early. Methods A face-to-face questionnaire survey was conducted for all women who gave birth in the Department of Obstetrics, the First Hospital of Shanxi Medical University from March 2012 to September 2016. A total of 10 319 qualified questionnaires were collected to exclude 9 623 cases of other hypertensive diseases related to pregnancy. A total of 70% of the subjects were randomly selected as training samples to analyze the influencing factors of pre-eclampsia, and a Logistic regression model was established. The remaining 30% of the objects are used as test samples to verify the effect of the model. Results Logistic regression model was established with training samples. Logit P=-2.517-0.696×Pre-pregnancy lean +0.200 ×Pre-pregnancy overweight +0.944×Pre-pregnancy obesity -1.995×Residential in city -0.409×Folic acid supplemented before pregnancy +1.323×Twin and multiple pregnancy +1.708× History of previous pregnancy hypertension. Homer-Lemeshow test P=0.377. Model AUC=0.767 (95%CI:0.747-0.786, P<0.001). Using the test sample to verify the model, the model sensitivity was 81.68%, the specificity was 75.05%, the positive likelihood ratio was 3.27, and the negative likelihood ratio was 0.24. The test sample model AUC = 0.771 (95%CI=0.763-0.790,P<0.001). Conclusion This study establishes a simple and effective pre-eclampsia risk assessment model with controllable factors. The model has good fit and sensitivity and specificity.
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@# Objective To compare performance of C5.0 decision tree models and radial basis function(RBF) neural network in predicting the risk of hemorrhagic transformation in acute ischemic stroke. Methods Patients with acute ischemic stroke admitted to hospital were enrolled. Hemorrhagic transformation group and non-hemorrhagic transformation group were divided according to whether hemorrhagic transformation occurred within 2 weeks after admission. Retrospectively collected patients’ case information. C5.0 decision tree models and RBF neural network model were established with the ratio of 7 :3 for training set and test set, and the prediction performance of the model was compared. Results A total of 460 patients’ case information were collected and divided in 314 training set samples and 146 test set samples. Accuracy rates of the C5.0 decision tree model were 96.5% and 80.1%, sensitivities were 98.1% and 82.6%, specificities were 94.8% and 77.9%, Kappa index were 0.93 and 0.60, and AUC were 0.97 and 0.80. Accuracy rates of the neural network model were 72.6% and 74.7%, sensitivities were 87.6% and 88.4%, specificities were 56.9% and 62.3%, Kappa index were 0.45 and 0.50, and AUCs were 0.72 and 0.75. In the training set, the prediction performance of the C5.0 decision tree model was superior to the RBF neural network model. However, there was no statistical difference in the test set.Conclusion C5.0 decision tree model is better than RBF neural network model in risk prediction.
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Purpose To analyze the effects of full length and N-terminal fragment of serum response factor (SRF-Full and SRF-N) on TGF-β1-induced differentiation in c-Kit + cardiac stem cells (CSC).Methods Rat SRF-Full and SRF-N (1-254 aa) coding sequences were obtained from cDNA library and cloned into the linearized lentviral vector GV358 (Ubi-MCS3FLAG-SV40-EGFP-IRES-puromycin) to generate the recombinant vectors,and then positive clones were selected and sequenced after transducing the competent cells with recombinant vectors.The recombinant lentvirus were packaged through transfecting the HEK293T cells with SRF-Full,SRF-N overexpressing plasmids and viral packaging plasmids.Neonatal SD rat cKit + CSCs were isolated via magnetic activated cell sorting,and TGF-β1-induced differentiation in SRF-Full and SRF-N overexpression virus-infected CSCs was assessed by quantitative PCR.Results SRF-Full and SRF-N coding sequences were successfully obtained and properly cloned into the linearized GV358.The positive clones were selected and further confirmed by sequencing.With the help of packaging plasmids,the SRFFull and SRF-N overexpressing plasmids-transfected HEK293T cells successfully produced the lentiviral particles with the titer of 2 × 108 TU/mL,and the SRF-Full-Flag and SRF-N-Flag fusion protein were detected by Western blot in virus-infected HEK293T cells.Addition of TGF-β1 significantly induced upregulated mRNAs in cardiomyocyte markers (Nkx2.5,Gata4,cTnI) and smooth muscle cell marker (SM22α) but not the epithelia cell marker (vWF) in CSCs.Overexpression of SRF-Full facilitated TGF-β1-triggered cardiomyocyte differentiation.However,SRF-N exerted anti-differentiation effects in TGF-β1-treated cells.Conclusion The SRF-Full and SRF-N overexpressing recombinant lentiviral vectors are successfully constructed.SRF-Full facilitates while SRF-N suppresses TGF-β1-induced cardiomyocyte differentiation in c-Kit + CSCs.
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BACKGROUND: Serum creatinine (SCr) is the most commonly used parameter to estimate renal function impairement, but there are some shortcomings. Many factors including age, gender, drug, diet, muscle mass and metabolic rate can influence SCr, leading to an inaccurate estimation of kidney impairment. Studies have shown that cystatin C (CysC) is not affected by factors such as muscle mass, age, gender, diet, inflammation or tumor. The present study was undertaken to compare the sensitivity of CysC and SCr in evaluating renal function impairment at early stage of shock. METHODS: Seventy-one patients aged 38.3±21.4 years, who had been treated at the Emergency Medicine Department of the First Affiliated Hospital, Sun Yat-sen University between February 2006 and June 2007, were studied. They were divided into groups A, B, C, and D according to the shock time. Serum sample was drawn from each patient at 1, 2, 3, 4 hours after shock to determine SCr and CysC. CysC and SCr were determined again at 72 hours and 7 days after shock. RESULTS: CysC increased earlier than SCr in the 71 patients, and CysC decreased slower than SCr when shock was corrected. CysC increased at 1 hour after shock. There was a negative correlationship between CysC, SCr and glomerular filtration rate (GFR), especially at early stage of shock. CONCLUSIONS: There is renal injury at early stage of shock. CysC is more sensitive than SCr in assessing renal function at the early stage of shock.