Objective To study the effect of DNA methyltransferase 1(DNMT1)on sm-like protein-4(LSM4)in hepatocyte apoptosis in mice induced with Hcy.Methods 12 ApoE-/-mice were divided into two groups:normal diet(ND,n=6)and high methionine diet(HMD,n=6)groups.Normal hepatocytes of NCTC1469 were divided into a normal group(control,0 μL/L Hcy),Hcy intervention group(Hcy,100 μL/L Hcy),NC siRNA-transfected control group(si-NC group,0 μmol/L Hcy),LSM4 siRNA-transfected group(si-LSM4 group,0 μmol/L Hcy),DNMT1 siRNA-transfected group(si-DNMT1 group,0 μmol/L Hcy),NC siRNA-transfected Hcy intervention group(Hcy+si-NC group,100 μmol/L Hcy),LSM4 siRNA-transfected Hcy intervention group(Hcy+si-LSM4 group,100 μmol/L Hcy),and DNMT1 siRNA-transfected Hcy intervention group(Hcy+si-DNMT1 group,100 μmol/L Hcy).Analysis of the expression of LSM4 in various tissues was conducted using the NCBI database.Quantitative real-time PCR(qRT-PCR)and Western blot were used to detect differences in LSM4 protein expression in mouse tissues(HMD and ND)and hepatocytes(control and Hcy).Western blot was used to detect the expression of Bcl2-associated X(Bax)and B-cell lymphoma-2(Bcl-2).The cell apoptosis rate in the Control,Hcy,Hcy+si-NC,and Hcy+si-LSM4 groups were detected by flow cytometry.MethPrimer online software was used to analyze the CpG islands of LSM4 promoter region.The expression of LSM4 in the Hcy+si-DNMT1 group was detected by qRT-PCR and Western blot.Results The expression of LSM4 in HMD,Hcy group was higher than that in the ND and Control group(P＜0.05).Bax protein expression was significantly higher,but Bcl-2 was significantly lower in Hcy group compared with those of the Control group(P＜0.05).The expression of Bax protein was significantly lower,but the level of Bcl-2 was significantly higher in the Hcy+si-LSM4 group compared with those in the Hcy+si-NC group(P＜0.05).The cell apoptosis rate in the Hcy group was higher than that in the Control group(P＜0.05),while the apoptosis rate in the Hcy+si-LSM4 group was lower than that in the Hcy+si-NC group(P＜0.05).MethPrimer database analysis showed that the promoter region of LSM4 was GC-rich,and there was one CpG island.Compared with the Hcy+si-NC group,the Hcy+si-DNMT1 group's expression of LSM4 protein was increased(P＜0.05).Conclusions DNMT1 regulates LSM4 hypomethylation to increase its expression,thereby promoting Hcy-induced apoptosis of mouse hepatocytes.

Objective To study the effect of DNA methyltransferase 1(DNMT1)on sm-like protein-4(LSM4)in hepatocyte apoptosis in mice induced with Hcy.Methods 12 ApoE-/-mice were divided into two groups:normal diet(ND,n=6)and high methionine diet(HMD,n=6)groups.Normal hepatocytes of NCTC1469 were divided into a normal group(control,0 μL/L Hcy),Hcy intervention group(Hcy,100 μL/L Hcy),NC siRNA-transfected control group(si-NC group,0 μmol/L Hcy),LSM4 siRNA-transfected group(si-LSM4 group,0 μmol/L Hcy),DNMT1 siRNA-transfected group(si-DNMT1 group,0 μmol/L Hcy),NC siRNA-transfected Hcy intervention group(Hcy+si-NC group,100 μmol/L Hcy),LSM4 siRNA-transfected Hcy intervention group(Hcy+si-LSM4 group,100 μmol/L Hcy),and DNMT1 siRNA-transfected Hcy intervention group(Hcy+si-DNMT1 group,100 μmol/L Hcy).Analysis of the expression of LSM4 in various tissues was conducted using the NCBI database.Quantitative real-time PCR(qRT-PCR)and Western blot were used to detect differences in LSM4 protein expression in mouse tissues(HMD and ND)and hepatocytes(control and Hcy).Western blot was used to detect the expression of Bcl2-associated X(Bax)and B-cell lymphoma-2(Bcl-2).The cell apoptosis rate in the Control,Hcy,Hcy+si-NC,and Hcy+si-LSM4 groups were detected by flow cytometry.MethPrimer online software was used to analyze the CpG islands of LSM4 promoter region.The expression of LSM4 in the Hcy+si-DNMT1 group was detected by qRT-PCR and Western blot.Results The expression of LSM4 in HMD,Hcy group was higher than that in the ND and Control group(P＜0.05).Bax protein expression was significantly higher,but Bcl-2 was significantly lower in Hcy group compared with those of the Control group(P＜0.05).The expression of Bax protein was significantly lower,but the level of Bcl-2 was significantly higher in the Hcy+si-LSM4 group compared with those in the Hcy+si-NC group(P＜0.05).The cell apoptosis rate in the Hcy group was higher than that in the Control group(P＜0.05),while the apoptosis rate in the Hcy+si-LSM4 group was lower than that in the Hcy+si-NC group(P＜0.05).MethPrimer database analysis showed that the promoter region of LSM4 was GC-rich,and there was one CpG island.Compared with the Hcy+si-NC group,the Hcy+si-DNMT1 group's expression of LSM4 protein was increased(P＜0.05).Conclusions DNMT1 regulates LSM4 hypomethylation to increase its expression,thereby promoting Hcy-induced apoptosis of mouse hepatocytes.

Objective To investigate the distribution and drug resistance of bacterial pathogens isolated from peritonsillar abscess .Methods Data on bacterial pathogens isolated from peritonsillar abscess in Wenzhou Central Hospital from January 2010 to December 2014 were retrospectively analyzed .Strains were identified with Vitek 32 identification system and the drug susceptibility test was performed with K-B method.Chi-square test for linear trend was performed to reveal the changes of distribution and drug resistance of the strains .Results A total of 2 864 bacterial strains were isolated in five years , in which 1 786 strains were Gram-negative bacilli (62.4%), and 1 078 (37.6%) strains were Gram-positive cocci. The positive rate of Gram-negative bacilli was on the rise during year 2010-2014 (χ2 =84.74, P<0.01), and the top three Gram-negative bacilli were Pseudomonas aeruginosa, Acinetobacter baumannii and Haemophilus influenzae, which accounted for 72.5%(1 295/1 786) of the total Gram-negative strains, and the positive rates of first two bacilli were on the rise (χ2 =83.75 and 24.74, P<0.01).Gram-positive cocci were mainly Staphylococcus aureus and Hemolytic streptococcus, which accounted for 83.2% ( 897/1 078) of the total Gram-positive strains.Resistance rates of Pseudomonas aeruginosa to ceftazidime, cefoperazone, piperacillin/tazobactam were on the rise (χ2 =16.17, 13.48 and 11.44, P<0.05), while resistance rates to gentamicin and amikacin were on the decline (χ2 =16.54 and 16.63, P <0.05). Resistance rates of Acinetobacter baumannii to ceftazidime, cefoperazone/sulbactam and piperacillin/tazobactam were on the rise (χ2 =12.52, 10.85 and 14.14, P<0.05).Resistance rates of Haemophilus influenzae to ampicillin were on the rise (χ2 =10.21, P<0.05), and the positive rate of β-lactamase producing strains was also on the rise (χ2 =10.38, P<0.05).Resistance rates of Staphylococcus aureus to cefazolin and methicillin were on the rise (χ2 =15.44 and 12.53, P<0.05), but no vancomycin resistant strain was found .Hemolytic streptococcus were sensitive to all commonly used antibiotics .Conclusions Peritonsillar abscess in Wenzhou Central Hospital is mainly induced by Gram-negative bacilli infection . Pseudomonas aeruginosa, Acinetobacter baumannii and Staphylococcus aureus are the top three bacterial pathogens , and are highly resistant to most antibiotics .