布比卡因对窦房结细胞和心肌细胞动作电位的影响

本文采用微电极技术研究了布比卡因对窦房结细胞和心肌细胞动作电位(AP)的影响。实验发现布比卡因使窦房结细胞AP之APA、Vmax和SP4降低;APD50、APD90和SCL延长,SFF减慢。心肌细胞AP之APA和Vmax降低,RMP减小,APD20缩短,APD50和APD90延长。结果表阴,布比卡因对窦房结细胞AP之O期和4期中起主要作用的缓慢内向电流(Isi)具有明显的抑制作用,因而能明显抑制窦房结的自律性,延缓窦房传导。此外,布比卡因对心肌细胞快反应AP的作用表明,其对钠(INa)、钾(Ik)和钙(ISi)通道均有显著的抑制作用.可使心肌AP的传导速度明显减慢而易于发生传导阻滞和折返激动。因此,本文的实验结果提示,毒性剂量的布比卡因可能通过使RMP减小,Vmax降低,浦肯野纤维至心室肌(PF-VM)的传导阻滞和显著而不均一的APD变化等机制促使折返型心律失常的发生。

Human cytomegalovirus induces alteration of β-actin mRNA and microfilaments in human embryo fibroblast cells

Objective: To investigate the infection of human embryo fibroblast cell line HF cells by CMV as well as the effects of CMV on β-actin mRNA and microfilaments. Methods: HF cells shape was observed after the infection of CMV.RT-PCR assay was used to detect the mRNA expression of CMV immediate early (IE) gene, β-actin and GAPDH genes of HF cells infected by CMV. CMV particles and cell microfilaments were detected with electron microscope. Results: Shape of HF cell changed after the infection by CMV. HF cells infected by CMV could express IE mRNA and the expression of β-actin mRNA decreased in a time-and titer-dependent manner compared with the uninfected HF cells whose expression of GAPDH mRNA did not change much. CMV particles were found with electron microscope in the cells. Microfilaments were ruptured and shortened after the infection of CMV. Conclusion: CMV can not only infect human embryo fibroblast cells line HF cells and replicate in the cells, but can also affect the expression of β-actin mRNA and the microfilaments.

Oxidative modification of high density lipoprotein induced by cultured human arterial smooth muscle cells

Objective: To observe the oxidative modification of high density lipoprotein (HDL) induced by cultured human arterial smooth muscle cells (SMCs). Methods: HDL cocultured with SMCs at 37℃ in 48 h was subjected, and native HDL (N-HDL) served as control. Oxidative modification of HDL was identified by using agarose gel electrophoresis. Absorbances of conjugated diene (CD) and lipid hydroperoxide (LOOH) were measured with ultraviolet spectrophotometry at 234 and 560 nm respectively, and fluorescence intensity of thiobarbuturic acid reaction substance (TBARS) with fluorescence spectrophotometry at 550 nm emission wavelength with excitation at 515 nm. Results: In comparison with N-HDL, the electrophoretic mobility of SMCs-cocultured HDL was increased, and the contents of CD, LOOH and TBARS HDL were very significantly higher than those of the control HDL (P<0.01). Conclusion: Oxidative modification of HDL can be induced by human arterial SMCs.

Nitric oxide production and inducible nitric oxide synthase protein expression in human abdominal aortic aneurysms and cultured aneurismal smooth muscle cells

Objective：To investigate the production of nitric oxide（NO） and the expression of inducible nitric oxide synthase （iNOS）, and their possible role in abdominal aortic aneurysm （AAA）. Methods： A total of 28 patients with AAA, 10 healthy controls, and 8 patients with arterial occlusive disease were enrolled into this study. Standard colorimetric assay was used to examine NO concentration in plasma from patients with AAA and normal controls, and in cultured smooth muscle cells （SMCs）. Expression of iNOS in aortas and cultured SMCs were detected by immunochemistry. The correlation of iNOS expression with age of the patient, size of aneurysm, and degree of inflammation was also investigated by Cochran-Mantel-Haenszel χ^2 test and Kendall correlation. Results ： Expression of iNOS increased significantly in the wall of aneurism in the patients with AAA compared to the healthy controls （P〈0.05） and the patients with occlusive arteries （P〈0.05）. iNOS protein and media NOx （nitrite＋nitrate） also increased in cultured SMCs from human AAA （n=4, P〈0.05）, while plasma NOx decreased in patients with AAA （n= 25） compared to the healthy controls （n=20）. There was a positive correlation between iNOS protein and the degree of inflammation in aneurismal wall （Kendall coefficient = 0. 5032, P= 0. 0029）. Conclusion： SMCs and inflammatory cells are main cellular sources of increased iNOS in AAA, and NO may play a part in pathogenesis in AAA through inflammation, SMCs and oxidative stress.

Effects of nerve growth factor on delayed afterdepolarization and triggered activity in the infarcted ventricle of rabbit model

The noninfarcted myocardium underwent significant electrophysiological remodelling as part of the healed myocardial infarction remodelling. This study aimed at investigating the effects of nervous growth factor （NGF） on delayed afterdepolarizations （DADs） and triggered activity （TA） of the noninfarcted myocardium in the myocardial infarcted rabbit model. Rabbits with the left anterior descending coronary artery occlusion were prepared and recovered for 8 weeks （HMI group, n=9）. Other rabbits with myocardial infarction were infused NGF to the left stellate ganglion （HMI＋NGF group, 400 U/day for 8 weeks, n=8）. Myocytes were isolated from regions of the noninfarcted left ventricular free wall. Action potentials and ion currents were recorded with whole-cell patch clamp. The results showed that more DADs and TA events of HMI＋NGF myocytes than that of HMI and Ctrl group. Iti and ICa-L of NGF＋HMI myocytes were increased significantly compared with HMI and Ctrl cells, which contributed to DADs-related triggered arrhythmia. Comparing with HM1 and Ctrl myocytes, significant prolongations of APD50 and APD90 in HMI＋NGF myocytes were found. The results indicated the electrophysiological change of HMI myocytes with NGF infusion. It suggested that more events of DADs and TA in HMI myocytes with NGF treatment. The underlying mechanism may be involved in the increase of Iti and ICa-L.

Treatment of 104 Cases of Chemotherapy-Induced Leukopenia by Injection of Drugs into Zusanli

From April 1992 to April 1998, 104 cases of chemotherapy-induced leukopenia were treated by injection into Zusanli (ST 36) with a mixture consisting of dexamethasone, 654-2, ATP and inosine. The therapeutic results were satisfactory as reported in the following.Clinical Data In this series, all the 127 cases were definitely diagnosed by pathological examination. Of them, 93 were male and 34 female, ranging in age from 12 to 75 years. 38 cases were carcinoma of esophagus, 22 carcinoma of cardia of stomach, 21 cancer of lung, 11 hepatic carcinoma, 8 lymphoma, 8 mammary cancer, 7 carcinoma of colon, and 12 other kinds of the tumors. Leukocyte count was below 4.0×109/L in all the patients after being treated by chemotherapy.

A bioinformatics method for predicting long noncoding RNAs associated with vascular disease

Long noncoding RNAs(lncRNAs)play important roles in human diseases including vascular disease.Given the large number of lncRNAs,however,whether the majority of them are associated with vascular disease remains unknown.For this purpose,here we present a genomic location based bioinformatics method to predict the lncRNAs associated with vascular disease.We applied the presented method to globally screen the human lncRNAs potentially involved in vascular disease.As a result,we predicted 3043 putative vascular disease associated lncRNAs.To test the accuracy of the method,we selected 10 lncRNAs predicted to be implicated in proliferation and migration of vascular smooth muscle cells(VSMCs)for further experimental validation.The results confirmed that eight of the 10 lncRNAs(80%)are validated.This result suggests that the presented method has a reliable prediction performance.Finally,the presented bioinformatics method and the predicted vascular disease associated lncRNAs together may provide helps for not only better understanding of the roles of lncRNAs in vascular disease but also the identification of novel molecules for the diagnosis and therapy of vascular disease.