1.Distinct effects of different β-adrenoceptor stimulation patterns on car-diac AMP-activated protein kinase activity
Han XIAO ; Xiaowei MA ; Yongnan FU ; Youyi ZHANG ; Zhizhen Lü
Chinese Journal of Pathophysiology 2016;32(12):2177-2183
[ ABSTRACT] AIM:To investigate the cardiac AMP-activated protein kinase ( AMPK) activity and the effects of AMPK activator on cardiac structure and function in the mice with different β-adrenoceptor (β-AR) stimulation patterns . METHODS:Male BALB/c mice were subcutaneously injected with AMPK activator ( AICAR, 250 mg· kg -1 · d-1 ) or saline, and infused with β-AR agonist isoproterenol (ISO, 5 mg· kg-1· d-1) for 14 d.The cardiac functions were evalu-ated by echocardiography or hemodynamic method , and the hearts were harvested after infusion cessation immediately or 3 d later.Phosphorylated AMPK ( p-AMPK) was measured by Western blot .RESULTS:Sustained ISO infusion increased p-AMPK level.AICAR did not further increase p-AMPK but attenuated ISO-induced increase in heart weight .Sustained ISO infusion increased cardiac systolic function as indicated by left ventricular fractional shortening ( FS) and maximum rate of pressure rise (+dp/dtmax).The cardiac systolic function was not further increased by AICAR .The cardiac diastolic func-tion as indicated by left ventricular end-diastolic pressure (LVEDP) was not different in each group .In contrast, cardiac p-AMPK level was similar between the control mice and the mice with sustained ISO infusion and ceased infusion for 3 d. In this model, AICAR improved the cardiac systolic and diastolic functions , which were impaired by ISO.Moreover, the increased pattern of p-AMPK level was similar with that of heart rate upon ISO stimulation .CONCLUSION: Sustained ISO infusion increases p-AMPK.After ISO infusion cessation for 3 d, p-AMPK is decreased to the basal level .β-AR-in-duced inotropic effects should be avoided to investigate the cardioprotective role of AMPK activation in the β-AR stimulation models.
2.Isoproterenol regulates lipopolysaccharide-induced tumor necrosis factor-alpha and interleukin-6 production in monocytes from essential hypertensive patients
Han XIAO ; Jie YU ; Zhaoping LI ; Youyi ZHANG
Journal of Peking University(Health Sciences) 2003;0(06):-
0.05). Conclusion: ?-adrenergic activation inhibits TNF-? (but not IL-6) production induced by LPS in monocytes. The inhibitory effects were not different between early staged hypertensive patients and healthy subjects.
3.Impact of particulate matter in air pollution on cardi ovascular diseases
Han XIAO ; Zijian LI ; Qide HAN ; Youyi ZHANG
Chinese Journal of Pathophysiology 1986;0(04):-
Impact of air pollution on cardiovascular d is eases has been established. As the main source of city air pollution, particulat e matter has been demonstrated an independent correlation with incidence and mor tality of cardiovascular diseases. The mechanisms are not clear. Several plausib le mechanistic pathways have been described, including inflammation induced by o xidative stress, the followed enhanced coagulation/thrombosis resulted in instab ility of atherosclerosis, the promotion of ischemic heart diseases and imbalance of autonomic nerve tone resulted in the occurrence of arrhythmia. The article p rovides a review of the mechanisms on air pollution and cardiovascular diseases and suggestions for further research.
4.Development and evaluation for volume overload-induced and pressure overload-induced cardiac hypertrophy in rats
Minli ZHANG ; Han XIAO ; Yan BAI ; Youyi ZHANG ; Zhaoping LI
Chinese Journal of Pathophysiology 1986;0(04):-
AIM: To compare the evaluations for the structure and function of the hypertrophic hearts induced by volume overload or pressure overload in rats. METHODS: Volume overload-induced cardiac hypertrophy was established by abdominal aortacaval fistula (ACF) and pressure overload-induced cardiac hypertrophy was developed by constriction of aorta (CA). The cardiac structure and function were analyzed by echocardiography, hemodynamic determination, heart weight measurement and histological examination. RESULTS: Heart weight of rats in all the operated groups was increased compared to the sham-operated groups. In 1-week ACF group, the internal diameter (0.67?0.03)cm vs (0.60?0.02)cm, P
5.Earthquake crisis management and experience from the People's Hospital of Qingchuan County
Ping GUO ; Tiancai ZHANG ; Guangming ZHAO ; Youyi XIAO ; Yuhua GAO ; Yuchun MEI ; Yunchun FU ; Yutian CHUN
Chinese Journal of Hospital Administration 2008;24(8):505-506
In handling crises in hospitals caused by natural disasters like earthquake, systemati cpractical measures of crisis management are needed, which include: early contact with top managements for support in counter disaster supplies, immediate organization of temporary first aid stations by hospital staff, logistic support by full time personnel to solve problems such as drugs and medical equipments as well as food and drinking water, and psychological consultation to patients and staff members.
6.Application evaluation of GeneXpert MTB/RIF assay in the detection of rifampicin resistance and multidrug resistant tuberculosis
Jun CHEN ; Lifeng CHEN ; Yi REN ; Youyi RAO ; Jian YU ; Chang LIU ; Yong XIAO ; Baodong YUAN
International Journal of Laboratory Medicine 2019;40(2):144-148,152
Objective To explore the application values of GeneXpert MTB/RIF assay (Xpert assay) for rifampicin resistance and multidrug resistant tuberculosis (MDR-TB).Discordance of Xpert and L-J proportion DST of rifampicin was analyzed.Methods Specimens of 1 300patients from January 2014to June 2016in our hospital were collected for solid culture, Xpert assay and L-J proportion drug susceptibility test (DST).Rifampicin resistance detected by Xpert assay was compared with L-J proportion method as a gold standard.Sequencing of rpoB gene and determination of minimum inhibition concentration were accomplished on the discordant MTB strains between Xpert and L-J proportion DST.Results Compared with the DST, the sensitivity, specificity, positive and negative predictive value of Xpert assay for rifampicin resistance were 99.31%, 97.82%, 92.88%and 99.80%, respectively.Among 1 300culture-positive specimens, mutations were detected from 309specimens by Xpert assay, which included 125initial treatment and 184retreatment patients.Among309specimens with rpoB gene mutations, mutations detected by probes E, D and B were common, and the rates were 65.70%, 14.56%and 10.68%, respectively.Totally 239patients were MDR-TB[77.35% (239/309) ], of which 94initial treatment patients[75.20% (94/125) ]and 145retreatment patients[78.80% (145/184) ]were MDR-TB.Among 22strains which were detected rpoB gene mutations by Xpert, but sensitive by L-J proportion DST, 6strains had no mutation in rpoB gene rifampicin resistance determining region (RRDR);16strains had mutations, which were mainly located in L511Pcodon (8strains) and L533Pcodon (4strains).Among 2strains which had no rpoB gene mutation by Xpert, but were resistant by L-J proportion DST, 1strain had no mutation in rpoB gene RRDR region;1strain had mutation which was located in E546G codon outside RRDR region.Conclusion Xpert assay can be used to rapidly detect rifampicin resistance and to screen MDR-TB.Mutations in codon 511and 533are related to low-level resistance to rifampicin.