Multilocus variable-number tandem-repeat analysis for molecular subtypes of Shigella isolates in Beijing / 中华预防医学杂志

<p><b>OBJECTIVE</b>Selecting variable-number tandem-repeat (VNTR) loci for different serogroups of Shigella spp to explore and establish multilocus variable-number tandem-repeat analysis (MLVA) method, in order to study the molecular characteristic of the isolated strains.</p><p><b>METHODS</b>Of the Shigella strains found by dysentery surveillance in Beijing from 2001 to 2009, 180 strains were selected for this study, according to the number and serotypes of the surveillant strains, at the ratio of 15%; including 50 strains of Shigella sonnei and 130 strains of Shigella flexneri. After screening the polymorphism of the 18 VNTR loci, 10 VNTR loci (sh1-sh10) were retained and constructed three groups of multi-PCR methods to detect all he 180 strains and analyze MLVA molecular subtypes using capillary segments.</p><p><b>RESULTS</b>A range of 2 to 11 alleles were found on the 10 VNTR loci among the 180 Shigella strains, with a diversity index value between 0.158 and 0.766. The 10 loci showed diversity in different serogroups, such as only one allele found in sh6 of Shigella flexneri, sh2 and sh3 of Shigella sonnei individually. The isolated 180 strains were divided into 84 MLVA subtypes, with a resolution ratio D value at 0.967 (95%CI: 0.956 - 0.978). The 130 strains of Shigella flexneri were divided into 63 subtypes, named as TF001-TF063; among which TF001, TF002 and TF 005 were the dominant subtypes, accounting to 17, 16 and 15 strains respectively. The 50 strains of Shigella sonnei were divided into 21 subtypes, named as TS001-TS021; among which TS002 (14 strains) and TS001 (7 strains) were the dominant subtypes.</p><p><b>CONCLUSION</b>MLVA subtyping method including 10 VNTR loci was preliminarily developed. The MLVA cluster analysis revealed that the subtypes of Shigella strains isolated in Beijing were diverse, and suggested the possibility of multiple-clone source.</p>

Analysis on the etiological and molecular epidemiological characteristics of Vibrio parahaemolyticus in Beijing / 中华流行病学杂志

Objective To understand the etiological and molecular-epiderniological characteristics of Vibrio parahaemolyticus in Beijing.Methods Stool specimens from sporadic diarrheal patients were collected during April to December,2010.Culture and serotyping were used to detect the Vibrio parahaemolyticus from the 2118 specimens.All the positive strains were tested for drug sensitivity by Kirby-Bauer method.Real-time PCR was used to detect the existence of three virulence genes tlh,tdh and trh.Molecular typing on Vibrio parahaerrolyticus isolates was completed by pulsed field gel electrophoresis(PFGE).Results 114 out of the 2118 specimens were Vibrio parahaemolyticus positive,with the positive rate as 5.38％.114 isolates belonged to 23 serotypes,with the dominant (63.16％)serotype as O3:K6.Strains isolated from clinical manifestation patients were resistant to antibiotics-ampicillin and gentamicin,while with high sensitivity to amoxicillin,ceftriaxone,chloromycetin,imipenem,nalidixic acid and tetracycline.Virulence gene detection was positive to tlh for all the strains,but most to tdh,while only one strain to trh.The positive rate oftdh among O3:K6 strains(98.61％)was higher than that in those non-O3:K6 strains(85.71％)(P=0.0098).114 isolates were discriminated into 54 different PFGE patterns,while 72 O3:K6 strains into 34 patterns without the clustering characteristic.Conclusion Vibrio parahaemolyticus strains isolated from diarrheal patients in Beijing were dominated by O3:K6 strains,with stronger virulence.The positive rates of genes tlh and tdh were high.Vibrio parahaemolyticus strains showed high sensitivity to most antibiotics.The prevalent Vibrio parahaemolyticus strains in Beijing had various sources of clones.

Epidemiological characteristics and molecular typing of Salmonella in Beijing from 2008 to 2009 / 中华预防医学杂志

<p><b>OBJECTIVE</b>To study the epidemiological characteristics and molecular phenotypes of Salmonella by pulsed-field gel electrophoresis (PFGE) in Beijing from 2008 to 2009.</p><p><b>METHODS</b>A total of one hundred thirty-seven isolates recovered from the WHO Global Salmonella Surveillance system and entero clinic surveillance system were identified by biochemical tests and serotyping. The related epidemiological informations were also analyzed. The isolates were further typed by PFGE.</p><p><b>RESULTS</b>The prevalence of Salmonella from 2008 to 2009 showed obvious seasonal character. High incidence occurred from June to September, and 64.1% (84/131) isolates were recovered in this period. Patients of 18 - 40 year-old were 46.1% (58/128) and 80 patients were male and 40 patients were female with the ratio of 1.57:1. These 137 Salmonella isolates belonged to 20 serotypes, including Enteritidis (46.7%, 64/137) and Typhimurium (17.5%, 24/137) as the dominant serotype. In total, 71 PFGE profiles were identified. Four PFGE patterns of S. Enteritidis isolates (JEGX01.CN0001, JEGX01.CN0003, JEGX01.CN0002, JEGX01.CN0019) and S. Typhimurium pattern of JPXX01.CN0001 were dominant patterns.</p><p><b>CONCLUSION</b>The prevalence of Salmonella from 2008 to 2009 showed distribution characteristics of sex, age and seasons. The numerous PFGE patterns of Salmonella showed diversity of these isolates and different clones existed in Beijing.</p>

Etiological surveillance and analysis of infectious diarrhea in Beijing in year 2010 / 中华预防医学杂志

<p><b>OBJECTIVE</b>To explore the pathogenic form, epidemic features and serotype distribution of the pathogenic bacteria causing infectious diarrhea in Beijing.</p><p><b>METHODS</b>A total of 2118 samples of rectal swabs and stool specimens of diarrheal patients were collected from 6 surveillant intestinal tract clinics during the period between April and October, 2010. Enteric multiple pathogens including Vibrio cholerae, Vibrio parahaemolyticus, Salmonella, Shigella and diarrheagenic Escherichia coli were detected by the isolation culture, biochemical identification and serotyping methods. The population distribution, temporal distribution and serotype distribution of the above pathogenic bacteria were analyzed by descriptive statistical methods.</p><p><b>RESULTS</b>478 strains isolated from the total 2118 specimens were positive for pathogen detection, accounting to 22.6%. Among the 478 strains of pathogenic bacteria, Shigella accounting for 40.8% (195/478) was the most frequent pathogen, followed by Vibrio parahaemolyticus accouting for 23.8% (114/478), Salmonella accounting for 19.0% (91/478) and diarrheagenic Escherichia coli accounting for 4.8% (23/478). Enteric pathogenic bacteria spread mainly among adults aging between 20 and 39; and the distribution was different among different age groups, while the highest detected rate was in 30 - 39 age group, accounting for 27.2% (92/338). The detected rate of pathogenic bacteria showed evident seasonal variations, with a peak from July to October, whose detected rates were 23.5% (114/486), 32.8% (176/536), 36.1% (90/249) and 25.9% (29/112) respectively. The detected rates in other months were all under 16.0%. Shigella Sonnei was the dominant serotype, accounting for 83.1% (162/195). O3:K6 was the dominant serotype among Vibrio parahaemolyticus, accounting for 63.2% (72/114). Salmonella Enteritidis and Salmonella Typhimurium were dominant serotypes among Salmonella, accounting for 13.2% (12/91) and 12.1% (11/91) separately. Enterpathogenic Escherichia coli and enterotoxigenic Escherichia coli were the dominant serotypes among Diarrheagenic Escherichia coli, accounting for 69.6% (16/23) and 30.4% (7/23) respectively.</p><p><b>CONCLUSION</b>The three main pathogenic bacteria causing infectious diarrhea in Beijing are Shigella, Vibrio parahaemolyticus, Salmonella; and there are obvious changes in the serotype distribution of Shigella and Samonella compared to previous years.</p>

Regulatory effect of lipo tiaozhi capsule on the expression of peroxisome proliferator-activated receptors mRNA in dyslipidemia rats and ApoE(-/-) mice / 中国中西医结合杂志

<p><b>OBJECTIVE</b>To study the regulatory effect of lipi tiaozhi capsule (LTC) on the expression of peroxisome proliferator-activated receptor (PPAR) alpha and gamma mRNA in dyslipidemia rats and ApoE(-/-) mice, and to explore its mechanisms for regulating lipid metabolism. Methods 48 Wistar rats were randomly divided into the blank group, the model group, the treatment group (treated by LTC), and the control group (treated by Xuezhi-kang Capsule). After four-week modeling (except the blank group) 30 ApoE(-/-) mice were randomly divided into the blank group, the treatment group, and the control group. LTC was given by gastrogavage to rats and ApoE(-/-) mice in LTC groups while XZKC was given to XZKC groups. The medication was conducted once daily for eight weeks. The serum TC and TG contents of rats and mice were determined by enzymic method. The serum high-density lipoprotein cholesterol (HDL-C) and low-density lipoprotein cholesterol (LDL-C) were detected by precipitation method. PPARalpha and gamma mRNA expressions were detected in the liver tissue of the rats and mice by fluorescent PCR.</p><p><b>RESULTS</b>Compared with the model group and the blank group, the serum contents of TC, TG, and LDL-C of rats or mice in the treatment group decreased significantly (P < 0.01). The serum content of HDL-C increased significantly (P < 0.01). PPARalpha and gamma mRNA expressions of rats or mice increased significantly (P < 0.01). Compared with the control group, the serum contents of TC, TG, and LDL-C of mice and rats in the treatment group decreased (all P < 0.05), the serum content of HDL-C increased significantly (P < 0.05, P < 0.01). And PPARalpha and gamma mRNA expressions of rats or mice increased significantly (P < 0.05).</p><p><b>CONCLUSION</b>LTC could significantly increase PPARa and y mRNA expressions of experimental dyslipidemia rats and ApoE(-/-) mice, playing roles in regulating nuclear factors and further effecting lipid metabolism.</p>

Study on the epidemiologic characteristics of norovirus infection in Beijing / 中华流行病学杂志

<p><b>OBJECTIVE</b>To investigate the epidemiological characteristics of norovirus infection in Beijing.</p><p><b>METHODS</b>Both outbreaks and sporadic cases of acute gastroenteritis were studied through questionnaires while the stools of patients were collected. Noroviruses were detected by ELISA or RT-PCR, and PCR products were cloned and sequenced.</p><p><b>RESULTS</b>Eight outbreaks were reported between November 2006 and March 2007, which were confirmed as nosocomial infections. A total of 158 positive cases were detected among 409 sporadic cases of acute virus gastroenteritis with a positive rate of 38.63%. The highest positive rate (55.00%) was found in group aged from 40 to 44, while the lowest positive rate (21.74%) fell into groups aged from 55 to 59. The positive cases aged from 6 months to 91 years with the mean age of 40 years old including 84 males and 74 females. Data from sequence analysis showed that norovirus epidemic strains helonged to the GII/4 variants in Beijing, which were almost identical to the variants causing epidemics both in the Netherlands and in Japan.</p><p><b>CONCLUSION</b>Norovirus was important, causing virus-borne diarrhea between 2006 and 2007 in Beijing, and the epidemic strains were consistent with those isolated from both the Netherlands and Japan in 2006.</p>

A preliminary study on molecular characteristics of noroviruses detected in Beijing / 中华流行病学杂志

<p><b>OBJECTIVE</b>To investigate the molecular characteristics of noroviruses detected in Beijing.</p><p><b>METHODS</b>From January to March 2007, cases from both outbreaks and sporadic episodes of acute nonbacterial gastroenteritis were investigated in Beijing, and the fecal specimens of the patients were collected. Noroviruses were detected by a reverse transcription polymerase chain reaction (RT-PCR), and then the PCR products were cloned and sequenced.</p><p><b>RESULTS</b>A total of 27 positive cases were identified as caused by noroviruses among the 38 patients with acute viral gastroenteritis, and four PCR products were randomly selected for further studies on sequencing. When comparing to the nucleotide sequences of norovirus reference strains from GenBank, the highest homology was found between the four isolates and the norovirus GII/4 strains. The four strains isolated from Beijing were almost identical to the GII/4 variants that causing epidemics in the Netherlands and in Japan with the homology of 97.8%-98.5% and 95.2%-95.9%, respectively. Phylogenetic analysis revealed that the four isolates were located at the same branch as the norovirus GII/4 variants in Netherlands and Japan.</p><p><b>CONCLUSION</b>New norovirus GII/4 variants were found in Beijing, and data from sequence analysis showed that the four isolates and the epidemic strains isolated from both the Netherlands and Japan in 2006 belonged to the same group of norovirus GII/4.</p>

Analysis about epidemic situation of dysentery near upon fourteen years in Beijing / 中华预防医学杂志

<p><b>OBJECTIVE</b>To realize the epidemiological and drug-resistance characteristics of dysentery during 1990 to 2003 in Beijing.</p><p><b>METHODS</b>The group's characteristics of dysentery were described and analysed by using descriptive study method. Drug sensitivity tests were performed with Kirby-Bauer method recommended by WHO, and data were analyzed with SPSS statistic software.</p><p><b>RESULTS</b>Average incidence rate was 222.24 /100 000 and incidence rate was high in children and in urban areas. The period of high incidence was found in July 16 to August 3. The equation of index-curve forecast model was gained as Y = e (5.816-0.5845x. It showed some value in predicting the tendency of dysentery. Shigella was sensitive to quinolones and cephalosporins, and there was no significant differences between the middle and high grade in these two kinds of antibiotics.</p><p><b>CONCLUSION</b>It should be taken as a measurement for the period of high incidence of dysentery.</p>

The correlation and clinic value of p53,p16,PCNA protein expressions in patients with esophageal carcinoma / 肿瘤研究与临床

Objective To study the expression of p53,p16,PCNA protein in esophageal carcinoma and its relationship to sexual distinction,the location of disease,the biological level,the depth of invasion and lymph node metastasis.Methods 118 patients with esophageal carcinoma were included in the study,all of them were treated for the first time.p53,p16 and PCNA protein in the 118 cases of esophageal carcinoma were detected by immunohistochemical assay(SP technique). Results The positive expression of p53, p16, PCNA protein in 118 patients was 80 %(92/118),42%(50/118)and 97%(115/118),respectively.The positive expression of p53,PCNA protein were irrelated to the sexual distinction,the location of disease,the biological level,the depth of invasion and the lymph node metastasis.The loss of p16 was significantly related to the depth of invasion and the lymph node metastasis(P