1.Isolation and molecular analysis of blaNDM-1-positive Morganella morganii
Xuan WANG ; Xiaoyan WU ; Jiaping LI ; Guorong SONG ; Bingfeng QIU ; Danxia GU ; Rong ZHANG
Chinese Journal of Laboratory Medicine 2015;38(12):857-860
Objective To investigate the molecular background of the New Delhi-metallo-1 (NDM-1)-producing Morganella morganii.Methods Two carbapenem-resistant M.morganii named 1 and 2 were isolated in the Second Hospital of Jiaxing,Zhejiang on October 4th and 29th,respectively.Antimicrobial susceptibility was determined by agar dilution method.Pulsed-field gel electrophoresis (PFGE) was performed to analyse the homololgy of isolates.Amplification with specific primers,DNA sequencing,conjugation experiments and genetic environment analysis were conducted to investigate the molecular mechanisms of resistance.Results The two M.morganii isolates were resistant to carbapenem and fluoroquinolones,while susceptible to aztreonam.PFGE analysis indicated that the two isolates were distinguishable.Amplification and DNA sequencing confirmed the coexistence of blaNDM-1,blasHv-12,qnrS1 and aac(6')-Ib-cr in both isolates.Transconjugants were detected with blaNDM.1 and qnrS1 simultaneously.Genetic environment analysis demonstrated that the blaNDM-1-bleMBL-trpF-dsbC-cutA1 structure was in consistence with those from known blaNDM-1-carrying Klebsiella pneumoniae.Conclusion The blaNDM-1 in M.morganii isolates possiblely obtained from K.pneumoniae through translatable plasmids.
2.Relationship between MIF expression and obese-induced abolition of sevoflurane preconditioning-in-duced cardioprotection in mice
Xiyan ZHANG ; Fanqing MENG ; Li ZHANG ; Dongliang LI ; Jiali WANG ; Qiya HU ; Bingfeng SONG ; Liang LI
Chinese Journal of Anesthesiology 2018;38(8):911-915
Objective To evaluate the relationship between macrophage migration inhibitory factor ( MIF) expression and obese-induced abolition of sevoflurane preconditioning-induced cardioprotection in mice. Methods Forty-eight male C57BL∕6J mice, aged 4 weeks, were divided into 2 groups ( n=24 each) using a random number table method: normal diet group ( Lean group ) and high-fat diet group ( Obese group) . Lean group were fed a normal diet ( 10% kcal) for 12 weeks, while Obese group were fed a high-fat diet ( 60% kcal) for 12 weeks. The weight of mice was measured. Blood samples were collected from the tail vein for determination of blood glucose concentrations, and plasma concentrations of total cho-lesterol, triglyceride, insulin and leptin. After measurement of the parameters mentioned above, Lean group and Obese group were divided into 3 subgroups ( n=8 each) using a random number table method:sham operation groups (L-Sham group, O-Sham group), myocardial ischemia-reperfusion groups (L-IR group, O-IR group) and sevoflurane preconditioning groups (L-IR+Sev group, O-IR+Sev group). The mice were anesthetized and their hearts were immediately removed and retrogradely perfused in a Langendorff apparatus with an oxygenated K-H solution at 37 ℃. Hearts were continuously perfused with K-H solution for 115 min in L-Sham and O-Sham groups. Hearts were subjected to global ischemia for 25 min, followed by 60-min reperfusion after being retrogradely perfused with K-H solution in L-IR and O-IR groups. In L-IR+Sev and O-IR+Sev groups, hearts were subjected to 3 cycles of 5-min perfusion with sevoflurane-contai-ning K-H solution ( final concentration 0. 6 mmol∕L) and 5-min washout, and then hearts were subjected to global ischemia for 25 min, followed by 60-min reperfusion. Left ventricular developed pressure ( LVDP ) , left ventricular end-diastolic pressure ( LVEDP ) , and the maximum rate of increase or decrease in left ventricular pressure ( ±dp∕dtmax) were recorded at the end of reperfusion. Hearts were obtained at the end of reperfusion for determination of myocardial infarct size and expression of MIF ( by Western blot) . Results Compared with Lean group, the weight, blood glucose, levels of plasma total cholesterol, tri-glyceride, insulin and leptin were significantly increased in Obese group (P<0. 05). Compared with L-Sham group, the LVDP and +dp∕dtmax were significantly decreased, LVEDP and -dp∕dtmax were in-creased, myocardial infarct size was increased, and the expression of myocardial MIF was up-regulated in L-IR and L-IR+Sev groups, and the expression of myocardial MIF was up-regulated in O-Sham group ( P<0. 05) . Compared with L-IR group, LVDP and +dp∕dtmax were significantly increased, LVEDP and-dp∕dtmax were decreased, myocardial infarct size was decreased, and the expression of myocardial MIF was up-regulated in group L-IR+Sev, and the expression of myocardial MIF was significantly up-regulated in group O-IR (P<0. 05). Compared with O-Sham group, LVDP and +dp∕dtmax were significantly de-creased, LVEDP and-dp∕dtmax were increased, and myocardial infarct size was increased, and no signif-icant change was found in the expression of MIF in O-IR and O-IR+Sev groups ( P>0. 05) . Conclusion The mechanism by which obese abolishes sevoflurane preconditioning-induced cardioprotection may be relat-ed to inducing MIF over-expression in mice.
3.Dysferlin deficiency: the cause of limb-girdle muscular dystrophy 2B and Miyoshi myopathy in a Chinese pedigree.
Shunchang SUN ; Qishi FAN ; Huacheng WU ; France LETURCQ ; Bingfeng ZHANG ; Wen YU ; Nathalie DEBURGRAVE ; Ming LIU ; Yongjian SONG
Chinese Journal of Medical Genetics 2004;21(2):128-131
OBJECTIVETo identify an inbred Chinese pedigree with autosomal recessive muscular dystrophy and analyze the molecular defects.
METHODSLinkage analysis was conducted using short tandem repeat(STR) markers from the regions associated with limb-girdle muscular dystrophy type 2A(LGMD2A) through 2H. Multi-Western blot was performed with anti-calpain-3, anti-dysferlin, anti-gamma-sarcoglycan, anti-alpha-sarcoglycan, and anti-dystrophin monoclonal antibodies. Mutation was determined by reverse transcriptase-polymerase chain reaction and sequencing.
RESULTSTwo-point linkage analysis showed significant Lod scores with markers from chromosome 2p13, the highest two-point Lod scores were obtained with D2S337 (Z(max)=1.86 at theta=0). Multi-Western blot confirmed dysferlin deficiency of muscle specimen from the proband. Mutation analysis revealed a novel 6429delG mutation on exon 53 of the DYSF gene for the proband.
CONCLUSIONThe authors identified an inbred Chinese pedigree with Miyoshi myopathy caused by a 6429delG on the DYSF gene. This mutation is predicted to result in premature termination of translation.
DNA, Complementary ; chemistry ; Dysferlin ; Genetic Linkage ; Humans ; Male ; Membrane Proteins ; genetics ; Middle Aged ; Muscle Proteins ; genetics ; Muscular Diseases ; genetics ; Muscular Dystrophies ; genetics ; Mutation ; Pedigree