1.Pulmonary Infection Status, Drug-resistance and Risk Factors of Extended-spectrum ?-Lactamases-producing Bacteria
Lin TENG ; Fen SU ; Ting LIU ; Yongqiang ZHEN ; Liping WU ; Kaiyu SUN ; Leqiang WANG
Chinese Journal of Nosocomiology 2006;0(09):-
OBJECTIVE To survey the patient with pulmonary infection induced by extended-spectrum ?-lactamases-producing bacteria and their Enterobacteriaceae clinical characteristics, drug-resistance and countermeasure. METHODS Isolation, cultivation, identification, drug-sensitivity tests and confirmation of ESBLs-producing bacteria were done for the bacteria of sputum specimens collected from our hospital from Feb 2001 to Sept 2004. Susceptibility testing was performed by disk diffusion(K-B)method. RESULTS Totally 541 strains of Enterobacteriaceae were cultivated altogether and ESBLs-producing bacteria were 135 strains. The ESBLs- producing strains were sensitive to imipenem, and the resistance rates to it were 0.00% . The resistance rates of ESBLs-producing strains to cefoperazone/sulbactam and piperacillin/tazobactam were 31.11% and 44.44%, respectively . The multi-drug-resistance (MDR) rate of ESBLs-producing strains was higher than that of strains no producing ESBLs (P
2.Effect of asiaticoside on systolic blood pressure and relaxation of isolated thoracic aorta of rats
Guoqing LU ; Hongyan SUN ; Zhengyu SUN ; Leqiang LIU ; Lei WANG ; Ningning ZHANG ; Yuhang WANG ; Yiming HE ; Jiahui JI ; Xinyue LI ; Pinfang KANG ; Bi TANG
Journal of Southern Medical University 2024;44(3):523-532
Objective To investigate the effect of asiaticoside on blood pressure and relaxation of thoracic aorta in rats and explore the underlying mechanism.Methods SD rats treated with 50 and 100 mg/kg asiaticoside by daily gavage for 2 weeks were monitored for systolic blood pressure changes,and histological changes of the thoracic aorta were evaluated using HE staining.In isolated rat endothelium-intact and endothelium-denuded thoracic aorta rings,the effects of asiaticoside on relaxation of the aortic rings were tested at baseline and following norepinephrine(NE)-and KCl-induced constriction.The vascular relaxation effect of asiaticoside was further observed in NE-stimulated endothelium-intact rat aortic rings pretreated with L-nitroarginine methyl ester,indomethacin,zinc protoporphyrin Ⅸ,tetraethyl ammonium chloride,glibenclamide,barium chloride,Iberiotoxin,4-aminopyridine,or TASK-1-IN-1.The aortic rings were treated with KCl and NE followed by increasing concentrations of CaCl2 to investigate the effect of asiaticoside on vasoconstriction induced by external calcium influx and internal calcium release.Results Asiaticoside at 50 and 100 mg/kg significantly lowered systolic blood pressure in rats without affecting the thoracic aorta histomorphology.While not obviously affecting resting aortic rings with intact endothelium,asiaticoside at 100 mg/kg induced significant relaxation of the rings constricted by KCl and NE,but its effects differed between endothelium-intact and endothelium-denuded rings.In endothelium-intact aortic rings pretreated with indomethacin,ZnPP Ⅸ,barium chloride,glyburide,TASK-1-IN-1 and 4-aminopyridine,asiaticoside did not produce significant effect on NE-induced vasoconstriction,and tetraethylammonium,Iberiotoxin and L-nitroarginine methyl ester all inhibited the relaxation effect of asiaticoside.In KCl-and NE-treated rings,asiaticoside obviously inhibited CaCl2-induced vascular contraction.Conclusion Asiaticoside induces thoracic aorta relaxation by mediating high-conductance calcium-activated potassium channel opening,promoting nitric oxide release from endothelial cells and regulating Ca2+ influx and outflow,thereby reducing systolic blood pressure in rats.
3.Effect of asiaticoside on systolic blood pressure and relaxation of isolated thoracic aorta of rats
Guoqing LU ; Hongyan SUN ; Zhengyu SUN ; Leqiang LIU ; Lei WANG ; Ningning ZHANG ; Yuhang WANG ; Yiming HE ; Jiahui JI ; Xinyue LI ; Pinfang KANG ; Bi TANG
Journal of Southern Medical University 2024;44(3):523-532
Objective To investigate the effect of asiaticoside on blood pressure and relaxation of thoracic aorta in rats and explore the underlying mechanism.Methods SD rats treated with 50 and 100 mg/kg asiaticoside by daily gavage for 2 weeks were monitored for systolic blood pressure changes,and histological changes of the thoracic aorta were evaluated using HE staining.In isolated rat endothelium-intact and endothelium-denuded thoracic aorta rings,the effects of asiaticoside on relaxation of the aortic rings were tested at baseline and following norepinephrine(NE)-and KCl-induced constriction.The vascular relaxation effect of asiaticoside was further observed in NE-stimulated endothelium-intact rat aortic rings pretreated with L-nitroarginine methyl ester,indomethacin,zinc protoporphyrin Ⅸ,tetraethyl ammonium chloride,glibenclamide,barium chloride,Iberiotoxin,4-aminopyridine,or TASK-1-IN-1.The aortic rings were treated with KCl and NE followed by increasing concentrations of CaCl2 to investigate the effect of asiaticoside on vasoconstriction induced by external calcium influx and internal calcium release.Results Asiaticoside at 50 and 100 mg/kg significantly lowered systolic blood pressure in rats without affecting the thoracic aorta histomorphology.While not obviously affecting resting aortic rings with intact endothelium,asiaticoside at 100 mg/kg induced significant relaxation of the rings constricted by KCl and NE,but its effects differed between endothelium-intact and endothelium-denuded rings.In endothelium-intact aortic rings pretreated with indomethacin,ZnPP Ⅸ,barium chloride,glyburide,TASK-1-IN-1 and 4-aminopyridine,asiaticoside did not produce significant effect on NE-induced vasoconstriction,and tetraethylammonium,Iberiotoxin and L-nitroarginine methyl ester all inhibited the relaxation effect of asiaticoside.In KCl-and NE-treated rings,asiaticoside obviously inhibited CaCl2-induced vascular contraction.Conclusion Asiaticoside induces thoracic aorta relaxation by mediating high-conductance calcium-activated potassium channel opening,promoting nitric oxide release from endothelial cells and regulating Ca2+ influx and outflow,thereby reducing systolic blood pressure in rats.
4.In Vivo Two-photon Calcium Imaging in Dendrites of Rabies Virus-labeled V1 Corticothalamic Neurons.
Yajie TANG ; Liang LI ; Leqiang SUN ; Jinsong YU ; Zhe HU ; Kaiqi LIAN ; Gang CAO ; Jinxia DAI
Neuroscience Bulletin 2020;36(5):545-553
Monitoring neuronal activity in vivo is critical to understanding the physiological or pathological functions of the brain. Two-photon Ca imaging in vivo using a cranial window and specific neuronal labeling enables real-time, in situ, and long-term imaging of the living brain. Here, we constructed a recombinant rabies virus containing the Ca indicator GCaMP6s along with the fluorescent protein DsRed2 as a baseline reference to ensure GCaMP6s signal reliability. This functional tracer was applied to retrogradely label specific V1-thalamus circuits and detect spontaneous Ca activity in the dendrites of V1 corticothalamic neurons by in vivo two-photon Ca imaging. Notably, we were able to record single-spine spontaneous Ca activity in specific circuits. Distinct spontaneous Ca dynamics in dendrites of V1 corticothalamic neurons were found for different V1-thalamus circuits. Our method can be applied to monitor Ca dynamics in specific input circuits in vivo, and contribute to functional studies of defined neural circuits and the dissection of functional circuit connections.