Objective To observe the clinical efficacy and safety of ultrapulse CO 2 laser-assisted au-tologous epidermal grafting for the treatment of vitiligo.Methods1605patients with30660skin grafts were treated by CO 2 laser-assisted autologous epidermal grafting.Among them,782patients had localized vi-tiligo,319segmental,226general and278scattered.Epidermal grafts were harvested with negative pressure blistering method from normally pigmented skin,and recipient areas were prepared with a ultrapulse CO 2 laser.The curative effect was evaluated8weeks later.Results79.04%of the lesions were cured complete-ly,and total response rate was92.21%,with better effect in localized and scattered lesions than in other le-sions.The best results were shown in face,while the worst results shown in brow and hairline lesions.Con-clusions The advantage of combined therapy of CO 2 laser with autologous epidermal grafting in vitiligo is of easy performance,convenience,high response rate,which is worthy of large scale application.

Objective To investigate the pathotypes,epidemiological characteristics and antimicrobial resistance of diarrheagenic Escherichia coli (DEC) in children with acute bacterial diarrhea in Shanghai.Methods A total of 2 071 outpatient children with probable acute bacterial diarrhea referred to the enteric clinic of Children's Hospital of Fudan University during June 2012 to June 2014 were enrolled in our study.The stool samples were processed for routine microbiologic and biochemistry tests to identify enteric bacteria,including enteropathogenic Escherichia coli (EPEC),enterotoxigenic Escherichia coli (ETEC),enteroinvasive Escherichia coli (EIEC) and enterohemorrhagic Escherichia coli (EHEC).Kirby-Bauer method was used to identify the antibiotic sensitivity.Difference of means between groups was compared by chi-square test.Results Of 2 071 enrolled children,DEC were identified in 145 (7.0 ％)cases.148 strains were isolated with three of mix infection strains.All DEC isolates in this study included 106 (71.6％) EPEC,24 (16.2％) ETEC,16(10.8％) EIEC and 2(1.4％) EHEC.The median ages of diarrheal children with DEC infections were 14 months (range:3 months to 13 years) and 62.8％ of them were ＜2 years.Among 125 DEC isolates tested for antimicrobial susceptibility,the rates of resistance to ampicillin,trimethoprim-sulfamethoxazole,cefotaxime,cefepime,gentamicin,ceftazidime,amoxicillinclavulanate,ciprofloxacin,and ofloxacin in a descending order were 55.2％,35.2％,28.0％,27.2％,23.2％,8.8％,5.6％,4.0％ and 4.0％,respectively.Resistance rates of EIEC to cefotaxime,cefepime and ceftazidime were 50.0％,43.8％ and 25.0％,respectively,which were higher than those of EPEC,ETEC and EHEC.Conclusion DEC is the important enteric bacteria that causes bacterial diarrhea in children in this study.

Objective To investigate the antimicrobial resistance and genotype distribution of staphylococcal cassette chromosome mec (SCCmec) of staphylococcus aureus (S.aureus) isolated from children hospitalized at Pediatric People's Hospital of Zhongjiang County.Methods Seventy-seven strains of S.aureus were collected by nasopharyngeal swabs at the Pediatric Department of People's Hospital of Zhongjiang County from January to December 2015.Methicillin-resistant staphylococcus aureus (MRSA) and methicillin-susceptible staphylococcus aureus (MSSA) were identified by cefoxitin disc diffusion and detection of mecA method.The minimum inhibitory concentrations (MIC) of antibiotics were determined by E-test method.SCCmec typing on MRSA strains was performed by using multiplex PCR.Results MRSA accounted for 54.5％ (42 strains) strains of 77 strains.All MRSA strains were resistant to Penicillin,and the rates of antibiotic resistance to Cefuroxime,Ceftriaxone,Erythromycin were 78.6％,95.2％ and 97.6％,respectively.The rates of antibiotic resistance of 35 MSSA to Penicillin and Erythromycin were 97.1％ and 62.9％,and they were also sensitive to other antibiotics.In 42 strains of MRSA,SCCmec type Ⅳa was the predominant type (27 strains,64.3 ％),which was followed by type Ⅳ g and Ⅴ (each 5 strains,11.9％),type Ⅳ c and Ⅳh (each 1strain,2.4％).Non-susceptibility rate of SCCmec Ⅳ to cefuroxime was significantly higher than that of other SCCmec types (P ＜ 0.05).Conclusions All strains from children hospitalized in People's Hospital of Zhongjiang County are often resistant to Penicillin and Erythromycin.The proportion of MRSA isolated from hospitalized children was high.SCCmec type Ⅳa is the main genotype of MRSA.

Objective To prepare simulated stool specimens for proficiency testing ( PT) by mix-ing lentils with Salmonella, Shigella and Escherichia coli strains and to establish an assessment scheme for the detection of Salmonella and Shigella in clinical samples. Methods Salmonella, Shigella and Escherich-ia coli strains were respectively spiked to lentils in Cary-Blair transport medium to create simulated stool specimens. Various ratios of Escherichia coli to Salmonella strains were spiked to lentils to prepare mixed simulated stool specimens. The accuracy and stability of prepared stool samples for PT were tested in-house. Results of sample detection were collected from participating laboratories for further external quality assess-ment. Results The Escherichia coli and Salmonella strains mixed at ratios of 100 ∶ 1 to 106 ∶ 1 could be ef-ficiently isolated from the media. Enrichment was needed in order to effectively isolate Salmonella strains from the media when the ratios of Escherichia coli to Salmonella strains were 104 ∶ 1 to 106 ∶ 1. Of the16 participating laboratories, 14 laboratories (87. 5%) received a grade of“satisfactory” and the other 2 labo-ratories (12. 5%) received a grade of “mainly satisfactory”. Conclusion The simulated stool specimens and the PT procedures designed in this study were suitable for proficiency testing program on the detection of Salmonella, Shigella and other similar microbes.

Objective To monitor the clinical epidemiology and etiology of acute diarrhea in children in the outpatient setting in Shanghai .Methods An active surveillance study in Children′s Hospital of Fudan University between August 2013 and July 2014 was conducted .Outpatient children with acute diarrhea were enrolled in this study and stool samples were collected .Pathogens including norovirus ,diarrheagenic Escherichia coli (DEC) , nontyphoidal Salmonella spp .(NTS),Campylobacter,Shigella,pathogenic vibrio and Yersinia enterocolitica were identified and typed .The χ2 test was used for statistical analysis .Results Of the 881 stool samples from enrolled children , the pathogens included into the target detection were identified in 246 (27 .92% ) cases . Norovirus ,DEC ,NTS ,Campylobacter and Shigella were detected in 98 (11 .12% ) cases ,74 (8 .40% ) cases , 61 (6 .92% ) cases ,34 (3 .86% ) cases and 2 (0 .23% ) cases ,respectively .Neither pathogenic vibrio nor Yersinia enterocolitica was identified .Children younger than 36 months old (3 .27% ,26/794) had a lower risk (χ2=7 .41 ,P=0 .006) of Campylobacter infection compared with older children (9 .20% ,8/87) .Vomiting (37 .76% ) and watery diarrhea (21 .34% ) were more commonly seen in children with norovirus infection;fever and mucous stool were commonly seen in diarrheal children with NTS infection (40 .98% and 21 .31% ,respectively) and Campylobacter infection (29 .41% and 26 .47% ,respectively) .Conclusion Enteric pathogens play a major role in childhood acute diarrhea in Shanghai .Continuous monitoring of enteric pathogens will be helpful for reasonable treatment and prevention of acute diarrhea in children .

Objective To analyze the serotype distribution and antibiotic resistance characteristics of Salmonella strains isolated in Guangdong province for better understanding the condition of Salmonella infection in patients with diarrhea.Methods Fecal samples collected from patients with diarrhea in Guangdong province were used to isolate Salmonella strains.Biochemical analysis was performed to identify these isolated strains.Serotyping and antimicrobial susceptibility testing were carried out for further analysis of the isolated Salmonella strains.Results The rate of Salmonella infection was 7.64％in 2015, and the male to female patient ratio was 1.52∶1.A total of 2 377 patients of all age groups were positive for Salmonella infection and the patients aged 0-6 years accounted for 81.74％.The isolation rate of Salmonella strains in the summer and autumn was higher than that in the winter and spring (10.73％ vs 4.24％;X2=463.77, P<0.01).The Salmonella isolation rates in different areas were as follows: 16.82％ in Zhuhai, 15.85％ in Heyuan, 11.81％ in Yangjiang, 10.68％ in Jiangmen, 8.49％ in Zhongshan, 8.07％ in Maoming, 8.05％ in Jieyang, 7.35％ in Shaoguan, 6.97％ in Foshan, 6.03％ in Dongguan, 5.48％ in Guangzhou and 0.00％ in Zhanjiang.And the differences between different regions were statistically significant (X2=367.67, P<0.01).The 2 377 isolated Salmonella strains were classified into 108 serotypes except for oneSalmonella strain that could not be classified.The top four predominant serotypes were 4,5,12:i:-, Salmonella enteritidis,Salmonella stanley and Salmonella typhimurium.Most Salmonella strains were sensitive to imipenem, azithromycin, ceftazidime, cefotaxime and trimethoprim/sulfamethoxazole, but multidrug resistance was common among those strains.Conclusion Salmonella serotypes of 4,5,12:i:-and Salmonella enteritidis are the predominant pathogens causing human Salmonella infections in Guangdong province.Ceftazidime and cefotaximeare are preferred in the treatment of Salmonella infections.Surveillance for drug resistance in Salmonella should be strengthened as multidrug resistant strains have become a serious problem in Guangdong province.

Plant dehydroascorbate reductase (DHAR) is a physiologically important reducing enzyme in the ascorbate-glutathione recycling reaction. In this study, two DHARs genes (SmDHAR1 and SmDHAR2) were isolated from Selaginella moellendorffii. The SmDHAR1 and SmDHAR2 genes encode two proteins of 218 and 241 amino acid residues, with a calculated molecular mass of 23.97 kDa and 27.33 kDa, respectively. The genomic sequence analysis showed SmDHAR1 and SmDHAR2 contained five and six introns, respectively. Reverse transcription PCR revealed that the SmDHAR1 and SmDHAR2 were constitutive expression genes in S. moellendorffii. The recombinant SmDHAR1 and SmDHAR2 proteins were overexpressed in E. coli, and were purified by Ni-affinity chromatography. The recombinant SmDHAR1 showed 116-fold higher enzymatic activity towards the substrate dehydroascorbate than recombinant SmDHAR2. The recombinant SmDHAR1 showed higher thermal stability than recombinant SmDHAR2. These results indicated obvious functional divergence between the duplicate genes SmDHAR1 and SmDHAR2.
Amino Acid Sequence ; Base Sequence ; Cloning, Molecular ; DNA, Plant ; genetics ; Escherichia coli ; genetics ; metabolism ; Molecular Sequence Data ; Oxidoreductases ; biosynthesis ; chemistry ; genetics ; Plant Proteins ; biosynthesis ; chemistry ; genetics ; Recombinant Proteins ; biosynthesis ; genetics ; Selaginellaceae ; enzymology ; genetics ; Sequence Analysis, DNA

Objective:To investigate the distribution characteristics of virulence-related phenotypes/genotype, capsular serotype, drug resistance phenotypes, and sequence typing (ST) of Klebsiella pneumoniae in patients living in Zhongjiang county, improve clinical understanding, and provide evidence for the prevention and control of bacterial drug resistance and clinical rational drug use. Methods:The data of 135 strains of Klebsiella pneumoniae isolated from patients who received treatment in Zhongjiang County People's Hospital from July to December 2019 were retrospectively analyzed. Bacterial identification and drug sensitivity testing were performed using the WalkAway-40Plus automated microbiology system. Strains with a high viscosity phenotype were identified using wire drawing experiments. Hypervirulence-associated capsular serotype and virulence genes were verified by polymerase chain reaction. ST of Klebsiella pneumoniae strain was identified using multilocus sequence typing. Results:Strains with a high viscosity phenotype were identified in 50.4% of the 135 strains. 54.1%, 54.8%, and 54.1% of the strains were positive for virulence genes iucA, iroN, rmpA. The proportion of strains with capsular Serotype K1 or K2 was 11.9% and 15.6%, respectively. A total of 65 kinds of ST were identified, with ST23 and ST37 being the most common, accounting for 11.1% and 6.7%, respectively. The resistance rate of the strains to 16 kinds of antibiotics was 0.0%-25.2%, and the resistance rate to Carbapenem antibiotics, Amikacin, and Tigecycline was less than 1%. The positive rate of virulence gene of strains with a high viscosity phenotype was significantly higher than that of strains without a high viscosity phenotype ( P < 0.001), and its resistance rate to Cephalosporin was significantly lower in strains with a high viscosity phenotype than that in strains without a high viscosity phenotype ( P < 0.001). Conclusion:Klebsiella pneumoniae in Zhongjiang County is characterized by "high virulence and low drug resistance". It is necessary to continuously monitor the changes in the virulence and drug resistance of Klebsiella pneumoniae in Zhongjiang County, Sichuan Province, and be alert to the rapid dissemination of highly virulent strains.

Objective To investigate the infection status, serotype distribution, drug sensitivity and molecular characteristics of diarrheagenic Escherichia coli (DEC) in patients with diarrhea in Guangdong Province. Methods Fecal samples were collected, cultured and isolated by traditional methods. Suspected Escherichia coli isolates were confirmed by multiplex PCR used for detecting specific virulence genes and bio-chemical methods. Positive strains were serotyped, characterized for drug sensitivity and analyzed by pulsed-field gel electrophoresis ( PFGE). Results The total positive rate of DEC in patients with diarrhea was 6.26%. The positive rates of enteropathogenic Escherichia coli (EPEC), enterotoxigenic Escherichia coli (ETEC), enterohemorrhagic Escherichia coli (EHEC), enteroadherent Escherichia coli (EAEC) and en-teroinvasive Escherichia coli (EIEC) were 2. 47% , 1. 54% , 1. 32% , 0. 62% and 0. 09% , respectively, with infections primarily in children aged 0-<7 years. The total seropositive rate was 52. 54% , with EHEC accounting for 15. 00% . DEC showed high sensitivity to imipenem, ciprofloxacin, ceftazidime and cefo-taxime. The multidrug resistance rate of DEC was 58. 45% , with EPEC being the most serious for multidrug resistance. PFGE results showed that ETEC, EHEC, EPEC and EAEC had a high degree of polymorphism. Conclusion EPEC is the predominant type of DEC circulating in Guangdong Province. Third-generation cephalosporins are the first drugs of choice for treating infections in children. Ciprofloxacin can be used to treat adults. The problem of multiple drug resistance of DEC is severe and efforts to monitor DEC infections and drug resistance should be strengthened.

Objective To understand the regional epidemiology and antibiotic resistance pattern of diarrheagenic E .coli infection in children ,and to clarify the pathogenic association between diarrheagenic E .coli infection and childhood diarrhea .Methods Totally 680 diarrheal children in the outpatient setting and 680 non-diarrheal control children were enrolled prospectively .The stool samples were collected and the potential enteric pathogens were detected .Minimal inhibitory concentration (MIC) method was used to determine the antimicrobial susceptibility for diarrheagenic E .coli isolates .Results The isolation rates of diarrheagenic E .coli in diarrhea group and control group were 15 .6％ and 13 .1％ ,respecitvely ,and diarrheagenic E .coli was the most commonly detected enteric bacteria .Multivariate logistic regression analysis adjusted for age suggested no clinical association between diarrhea and infection with enteropathogenic E .coli (EPEC) (aOR=1 .2 ,95％ CI:0 .8-1 .8) ,enteroadhesive E .coli (EAEC) (aOR=1 .1 ,95％ CI:0 .7 -1 .6) and enterotoxigenic E .coli (ETEC) (aOR= 1 .8 ,95％ CI:0 .5 -6 .2) . Among 199 diarrheagenic E .coli strains ,the rates of resistance to ampicillin ,tetracycline ,trimethoprim-sulfamethoxazole ,azithromycin ,and ceftriaxone were 63 .8％ ,55 .8％ ,48 .2％ ,34 .2％ and 26 .6％ , respectively ,while the rates of resistance to ciprofloxacin , amoxicillin-clavulanate and cefoxitin were 4 .5％ ,1 .5％ and 0 .5％ ,respectively .Conclusions Diarrheagenic E .coli is the most common enteric bacteria detected in the stool samples from children with and without diarrhea in this study . The pathogenic role of infections with EPEC ,EAEC and ETEC in childhood diarrhea is not determined .EHEC and EIEC are rarely detected and further studies are needed to clarify the pathogenic association between infection with EHEC ,EIEC and childhood diarrhea .