Objective To explore the mechanisms of angiotensin Ⅱ (Ang Ⅱ) induced apoptosis of cultured cardiomyocytes of neonatal rats. Methods Cultured neonatal rat cardiomyocytes were divided into three groups. Cells in the control group were incubated in serum-free medium for 2, 6, 12, and 24 h. Cells in Ang Ⅱ group were incubated with Ang Ⅱ at the dose of 10 -7 mol/L for 2, 6, 12, and 24 h. Cells in Ang Ⅱ and Ang Ⅱ type 1 receptor antagonist group were incubated in medium containing 10 -7 mol/ L Ang Ⅱ plus 10 -5 mol/L irbesartan. The apoptotic cells were detected by TUNEL assay. The Bcl-2 protein expression was assessed by immunohistochemistry. Caspase-3 activity was measured by a fluorescent assay kit. Results The number of apoptotic cells in Ang Ⅱ group increased significantly in a time-dependent manner, accompanied by decreased Bcl-2 protein expression but increased activity of caspase-3. Treatment with irbesartan resulted in decreased number of apoptotic cells and decreased activity of caspase-3. Conclusion Angiotensin Ⅱ could induce the apoptosis of neonatal rat cardiomyocytes through the caspase-dependent pathway, which might be mediated by Ang Ⅱ type 1 receptor. Bcl-2 may participate in the regulation.

This study aimed to investigate the prevalence and molecular characteristics of Listeria monocytogenes in cooked products in Zigong City, China. The overall occurrence of the L. monocytogenes in the ready-to-eat (RTE) shops and mutton restaurants surveyed was 16.2% (141/873). An occurrence of 13.5% was observed in RTE pork, 6.5% in RTE vegetables, and more than 24.0% in either cooked mutton or cooked haggis. Serotype 1/2b (45.4%), 1/2a (33.3%), and 1/2c (14.2%) were the predominant types. By comparing the clonal complexes (CCs) based on multilocus sequence typing (MLST) of the L. monocytogenes from cooked foods in Zigong City and 33 listeriosis cases from different districts of China, CC87, CC9, CC8, and CC3 were showed to be prevalent in cooked products and CC87 and CC3 were the first two frequent types in the 33 clinic-source strains. All CC87 stains harbored the newly reported Listeria pathogenicity island 4 (LIPI-4) gene fragment ptsA, and all CC3 strains possessed the Listeria pathogenicity island 3 (LIPI-3) gene fragment llsX. These may increase the occurrence of the strains belonging to CC87 and CC3 in listeriosis cases in China and also underline the risk of infection owing to the consumption of the cooked products from Zigong. ST619 (serotype 1/2b) harbored both llsX and ptsA, indicating a potential hypervirulent sequence type in Zigong.
China ; epidemiology ; Cooking ; Fast Foods ; microbiology ; Food Contamination ; Food Microbiology ; Humans ; Listeria monocytogenes ; genetics ; pathogenicity ; Listeriosis ; epidemiology ; microbiology ; Meat ; microbiology ; Multilocus Sequence Typing ; Prevalence ; Seasons