1.Effects of arachidonic acid on action potential and L-type calcium current in rabbit cardiomyocytes
Chengyun LIU ; Guiqing CHEN ; Xiaojing GENG
Chinese Journal of Pathophysiology 1999;0(09):-
AIM: To study the influence of arachidonic acid(AA) on the action potential and L-type calcium current in rabbit cardiomyocytes.METHODS: Single ventricular myocyte was isolated using enzyme dispersion method.Whole-cell clamp-patch technique was used to record action potential and L-type calcium current.RESULTS: ① AA shortened action potential duration obviously,without marked effect on the resting potential and action potential amplitude.② AA reduced the current densities from(10.21?3.15)PA/PF to(6.53?2.17)PA/PF(n=6,P
2.Effects of arachidonic acid on L-type calcium channel and its mechanism of antiarrhythmia
Chengyun LIU ; Guiqing CHEN ; Xiaojing GENG ; Xin CHEN ; Jingjing WAN
Chinese Journal of Emergency Medicine 2009;18(2):180-184
Objective To study the influence of arachidonic acid (AA) on L-type calcium channel in rabbits sin-gle cardiomyocyte and its mechanism of antiarrhythmia. Method The single ventricular cardiomyocyte was isolat-ed by using enzyme dispersion method and whole-cell clamp-patch technique was used to record L-type calcium current.All data were analyzed using ANOVA. Results AA inhibited Ica-L in a concentration-dependent manner. The application of 3 μmol/L, 10 μmol/L and 20 μmol/L arachidonic acid reduced the density of peak Ica-L from (10.79±0.93)pA/pF to (8.99±0.43)pA/pF to (7.60±0.35)pA/pF and to (5.60±0.30)pA/pF, respctive-ly (n=7, P<0. O1 ). The Ica-Lpartially resumed after washout. The AA up-shifted the I-V curves of Ica-L without changes of their shape,peak and reverse potentials. The AA also markedly shifted the inactivation curve to left, and prolonged the recorvery time from inactivation,but did not change the curve of calcium channel activation. Con-clustions By acceleration of L-type calcium channel inactivation and prolongation of recorvery time from inactiva-fion,arachidonic acid can reduce the calcium ion influe and prolong effective refractory period, playing the role of antiarrhythmia.
3.Clinical characteristics and perioperative management of abdominal aortic aneurysm in elderly patients
Chengyun LIU ; Tangmeng GUO ; Qunfang YANG ; Guiqing CHEN ; Lei JIANG ; Xiaojing GENG
Chinese Journal of Geriatrics 2008;27(10):747-749
ObjectiveTo investigate clinical characteristics and perioperative management of abdominal aortic aneurysm in elderly patients. MethodsThe clinical data of 24 patients aged 60 years and over with abdominal aortic aneurysm in our hospital were analyzed retrospectively. ResultsThe average age was 75.5 years and the proportion of male and female was 5 : 1. The course of disease was 2 days to 15 years and the median course was 2.8 months. 17 patients were complicated with hypertension, 5 patients with coronary heart disease, 4 patients with type 2 diabetes mellitus, 3 patients with chronic bronchitis, 2 patients with lacunar cerebral infarction, 3 patients with abdominal aortic aneurysm rupture, 13 patients with endovascular stent grafts, 10 patients with abdominal aortic aneurysm resection and artificial vascular replacement, 1 patient with endovascular stent grafts, endarterectomy of right femoral artery and right deep femoral artery,right deep femoral artery plasty and the application of artificial blood vessel in right femoro-popliteal arterial bypass. Postoperative complications happened in 15 cases (62.5%, 15/24) and the postoperative mortality rate was 20.8%.ConclusionsThe elderly patients with abdominal aortic aneurysm are always complicated with manyother chronic diseases such as hypertension, coronary heart disease , diabetes mellitus, chronicbronchitis. The operation for abdominal aortic aneurysm in elderly patients has high risk. Reasonablesurgical procedure and active perioperative management are the key for successful treatment.
4.Effects of recombinant human syntaxin-4(STX4) on lipopolysaccharide-induced islet β-cell INS-1 injury and underlying mechanism
Jianlin ZHAO ; Yufeng CHEN ; Suyu WU ; Jiangyan LI ; Chengyun XIONG ; Ying ZHANG ; Xiuqin GENG
Chinese Journal of Endocrinology and Metabolism 2021;37(8):738-744
Objective:To explore the effect of recombinant human syntaxin-4(STX4) on lipopolysaccharide(LPS)-induced injury in islet β-cells(INS-1).Methods:Pancreatic islet β-cells(INS-1) were divided into Control (blank control), LPS (LPS treatment), LPS+ NC (transfection of negative control vector, LPS treatment), and LPS+ STX4 (transfection of pcDNA-STX4, LPS treatment) groups. RT-qPCR and Western blot were used to detect STX4 mRNA and protein expression, flow cytometry to detect apoptosis, DCFHDA method to detect reactive oxygen species(ROS) level, xanthine oxidation method to detect superoxide orgotein dismutase(SOD) level, colorimetric method to detect glutathione peroxidase(GSH-Px) level, ammonium molybdate colorimetric method to detect catalase(CAT) level, thiobarbituric acid method to detect malonaldehyde(MDA) level, ELISA method to detect the level of interleukin-1β(IL-1β), tumor necrosis factor-α(TNF-α), and insulin secretion levels under glucose conditions secreted by cells, Western blot method to detect Cleared Caspase-3, Bcl-2 Associated X Protein(Bax), p65 protein expression. After treatment with NF-κB signaling pathway activator, STX4 up-regulated islet β-cell INS-1 was given LPS stimulation, and the same method was used to measure apoptosis, ROS, SOD, GSH-Px, CAT, MDA levels and secreted IL-1β, TNF-α, insulin levels and Cleaved Caspase-3, Bax, p65 protein levels.Results:Compared with the Control group, the expression of STX4 mRNA and protein in islet β cells of the LPS group decreased, the apoptosis rate, ROS level, and MDA levels increased, and the levels of SOD, GSH-Px, and CAT decreased, the levels of IL-1β, TNF-α increased, the level of insulin secreted by the cells decreased, and the expression levels of Cleaved Caspase-3, Bax, and p65 also increased. NF-κB pathway activator treatment reversed the effect of up-regulated STX4 on islet β-cell apoptosis, ROS, SOD, GSH-Px, CAT, MDA levels and secreted IL-1β, TNF-α levels, and Cleaved Caspase-3 , Bax and p65 protein levels.Conclusion:Up-regulation of STX4 alleviated LPS-induced islet β cell oxidative damage, apoptosis and inflammatory factor release. The underlying mechanism might be related to the inhibition of activated NF-κB signaling pathway.
5. The value of ultrasound classification in BI-RADS category 4 of breast complex cystic masses
Jinpeng YAO ; Lijuan NIU ; Yong WANG ; Chengyun GENG ; Qing CHANG ; Yu CHEN ; Li ZHU
Chinese Journal of Oncology 2018;40(9):672-675
Objective:
To analyze the feature of breast complex cystic masses and to classify it at ultrasonography (US), which applied to the Breast Imaging Reporting and Data System (BI-RADS) categories 4a to 4c with pathological results as the golden standards.
Methods:
The ultrasonographic data and clinical features of 78 patients with complex cystic masses confirmed by pathology in Cancer Hospital from July 2014 to June 2017 were retrospectively reviewed. The complex cystic breast masses were divided into four classes on the basis of their US features: type 1 [thick wall and (or) thick septa (> 0.5 mm)], type 2 (one or more intra-cystic masses), type 3 (mixed cystic and solid components with cystic components more than 50%) and type 4 (mixed cystic and solid components with solid components more than 50%). Positive values (PPVs) were calculated for each type. Multiple linear regression analysis was used to analyze the ultrasonographic features of the masses (lesion size, margins, blood flow resistance index, calcification, and axillary lymph nodes, etc.) with malignant correlation.
Results:
There were 81 lesions in 78 patients. Among the 81 masses based on US appearance, 14 (17.3%) were classified as type Ⅰ, 18 (22.2%) as type Ⅱ, 18 (22.2%) as type Ⅲ, and 31 (38.3%) as type Ⅳ. The positive predictive values of the malignant lesions of type Ⅰ, type Ⅱ, Ⅲ and Ⅳ were 7.1%, 16.7%, 61.1% and 48.3%, respectively (