1.The Community Succession of Sarcosaphagous Insects on Pig Carcasses in Summer Indoor and Outdoor Environment in Shenzhen Area
Xiaojun YIN ; Mengyun MA ; Hui ZHOU ; Yue LAI ; Jiangfeng WANG
Journal of Forensic Medicine 2014;(3):172-177
Objective To explore the growing development and community succession of main sarcos-aphagous insects on pig carcasses in summer indoor and outdoor environment in Shenzhen area and to estimate the postmortem interval (PMI). Methods From early May to August in 2013, in Forensic Med-ical Examination Center of Shenzhen Public Security Bureau, the main insect species and the decomposi-tion process were observed in two adult pig carcasses of simulative indoor and outdoor environment. The different decomposition stages and the community succession of insects were recorded. Results The indoor and outdoor pig carcasses showed skeleton 412.5 and 325 hours after death, respectively. The main species of flies on pig carcasses were Chrysomya megacephala, Chrysomya rufifacies and Chrysomya chani. The main species of beetles were Crecphilus maxillosus, Necrobia ruficollis, Saprinus splendens and Dermestes maculatu. The dominant species of flies in the outdoor pig carcasses obviously produced the second generations due to the effect of mass rainfall, nor in the indoor pig carcasses. Conclusion There are regular patterns on the community succession of insects on pig carcasses in summer indoor and out-door environment in Shenzhen area. The activity patterns of seven typical insects and their larva show important value for estimating PMI.
2.Kinetin inhibits apoptosis of aging spleen cells induced by D-galactose in rats.
Mengyun LI ; Wuqing OUYANG ; Xiaoli WU ; Yin ZHENG ; Yunpeng WEI ; Lei AN
Journal of Veterinary Science 2014;15(3):353-359
Kinetin (Kn) is a cytokinin growth factor that exerts several anti-aging and antioxidant effects on cells and organs. To investigate the mechanism underlying apoptotic events in aging cells induced by D-galactose (D-gal), we examined the effect of Kn delivered via nuchal subcutaneous injection on D-gal-induced aging and apoptosis in rats. Our results showed that interleukin (IL)-2 levels and mitochondrial membrane potential (DeltaPsim) were decreased by Kn in aging rats while IL-6 production and apoptosis increased. In addition, the expression of anti-apoptotic Bcl-2 was low while that of Bax was high in the aging group. After treated with Kn, compared with aging group, there showed obvious difference in Kn group with elevated IL-2, proliferation index, Bcl-2, DeltaPsim and decreased IL-6 and Bax in splenic lymphocyte. Based on these results, we concluded that Kn can effectively protect the rat spleen from aging, apoptosis, and atrophy.
Aging/drug effects/physiology
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Animals
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Apoptosis/drug effects/*physiology
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Female
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Galactose/*pharmacology
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Interleukin-6/physiology
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Interleukins/physiology
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Kinetin/pharmacology/*physiology
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Male
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Membrane Potential, Mitochondrial/drug effects/physiology
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Rats
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Spleen/*cytology/drug effects/physiology
3.Mechanism of action of suppressor of cytokine signaling 1 in the development and progression of liver inflammatory diseases
Xia WU ; Xiaoning ZHU ; Yurong ZHANG ; Yue YIN ; Mengyun PENG ; Ding ZHENG ; Jing WANG
Journal of Clinical Hepatology 2021;37(4):973-976
The development of liver inflammatory diseases is associated with autoimmunity and inflammatory response. As a negative feedback regulator of cell signal, suppressor of cytokine signaling 1 (SOCS1) plays a key role in the development and progression of inflammatory diseases. This article mainly introduces the mechanism of action of SOCS1 in autoimmunity and inflammatory response and briefly describes its role in the development and progression of liver inflammatory diseases such as viral hepatitis and nonalcoholic steatohepatitis. The analysis shows that the abnormal expression of SOCS1 in inflammatory response is associated with the regulation of cytokine receptor, Toll-like receptor, and hormone receptor signal, which leads to the development of inflammatory diseases. Therefore, SOCS1 has potential prospects as an auxiliary means for the diagnosis and treatment of liver inflammatory diseases.
4.Distribution and antimicrobial resistance of Enterobacter cloacae complex isolated from a tertiary hospital in Shanghai
Xiaoying YANG ; Chen WANG ; Mengyun YIN ; Youxing SHAO ; Fupin HU ; Minggui WANG ; Qinglan GUO
Chinese Journal of Infection and Chemotherapy 2024;24(3):332-337
Objective To investigate the distribution and antimicrobial resistance of Enterobacter cloacae complex(ECC)isolated from a tertiary hospital in Shanghai.Methods Clinical ECC isolates were collected from 2018 to 2020.Antimicrobial susceptibility test was performed with broth microdilution and agar dilution methods.PCR was applied to detect five carbapenemase genes(blaKPC,blaNDM,blaIMP,blaVIM and blaOXA-48).Results A total of 222 ECC isolates were collected from 2018-2020,including 36 strains(16.2%)from general surgery department.The strains were mainly isolated from sputum(41.0%)and urine(20.3%).MIC results showed that the isolates were highly resistant to trimethoprim-sulfamethoxazole,the second-and third-generation cephalosporins,aztreonam and quinolones(31.1%-71.2%resistant),but low resistance rates to tigecycline,amikacin,mecillinam,and ceftazidime-avibactam(0.5%-9.0%resistant).About 9.5%and 10.4%of the strains were resistant to meropenem and imipenem,respectively.A total of 34 ECC strains were carbapenem-nonsusceptible strains,of which 23 strains were resistant to carbapenems.Among the 34 carbapenem-nonsusceptible strains,25(73.5%)strains were susceptible to mecillinam,including 15 strains producing metallo-β-lactamase.PCR assay identified carbapenemase genes in 21 of the 34 carbapenem-nonsusceptible strains,including blaNDM(14 strains),blaIMP(5 strains)and blaKPC(2 strains).Compared with the strains isolated in 2018,the ECC strains isolated in 2019 and 2020 showed significantly higher resistance rates to imipenem and ceftazidime-avibactam(P<0.05),primarily associated with the production of NDM.Among the ECC strains resistant to third-generation cephalosporins,20.4%were resistant to imipenem and meropenem,while 4.9%and 8.7%were resistant to amikacin and mecillinam,respectively,and 9.7%were nonsusceptible to tigecycline.Conclusions The ECC isolates in 2019 and 2020 showed increasing resistance rates to carbapenems and ceftazidime-avibactam due to the production of metallo-β-lactamases.Some of the metallo-β-lactamase-producing ECC isolates were susceptible to mecillinam.