Effect of Icariin on Neuroprotection of Cerebral Ischemia-reperfusion Rats and TLR4/NF-κB Pathway in Microglia / 中国实验方剂学杂志

Objective:To investigate the effect of icariin on neuroprotection in cerebral ischemia-reperfusion rats and microglia toll-like receptor 4 （TLR4）/nuclear transcription factor-κB （NF-κB） pathway. Method:In the blank group， blood vessels were only isolated but not ligated and blocked，and the rats were injected intraperitoneally with the same volume of normal saline. After successful modeling， they were randomly divided into model group， butyphthalide group （6 mg·kg-1）， and high， medium and low （40，20，10 mg·kg-1）-dose icariin group，and abdominally administered with drugs at 5，12， 24 h after ischemia， respectively. The nerve function scores were detected， 2，3，5-triphenyltetrazole chloride （TTC） staining was used to measure the cerebral infarction rate，immunohistochemical assay was performed to detect the expressions of microglial markers ionized calcium binding adapter molecule 1（Iba1） and TLR4 in the rat brain cortex， Western blot immunoassay was used to detect the expression of NF-κB p65 in the cerebral cortex， and enzyme-linked immunosorbent assay （ELISA） was used to detect interleukin-1α （IL-1α） and tumor necrosis factor-α （TNF-α） content. Result:Compared with the sham-operation group， the nerve score， the cerebral infarction rate， the activations of Iba1 and TLR4 in microglial cells， the protein expression of NF-κB p65（P<0.01）， and the contents of inflammatory factors IL-1α and TNF-α in the model group increased significantly（P<0.01）. After treatment with icariin， compared with the model group， the neurological function score and the cerebral infarction rate of rats were improved， whereas the activations of Iba1 and TLR4 in microglia， the protein expression of NF-κB p65， and the contents of inflammatory factors IL-1α and TNF-α decreased obviously（P<0.05，P<0.01）. Conclusion:Icariin may inhibit the activations of TLR4 and its downstream NF-κB signaling pathway and reduce the expression of relevant inflammatory factors IL-1α and TNF-α by regulating the activation of microglia， so as to play a protective role in the brain after stroke.

Application of PulseNet China Database in tracking and warning 4 cholerae outbreaks in Anhui province, in 2012 / 中华流行病学杂志

<p><b>OBJECTIVE</b>To track the source of infection regarding 4 Cholerae outbreaks in Anhui province in 2012 through the application of PulseNet China Database (PNCD).</p><p><b>METHODS</b>Cholerae virulence genes were amplified by PCR and typed by pulse field gel electrophoresis(PFGE). Results from electrophoresis were cluster-analyzed by BioNumericsV4.0 software and compared with PNCD.</p><p><b>RESULTS</b>Virulence gene CT and TCP of the tested vibrio cholera showed both positive. Homology of the strains from four cholera outbreaks was more than 98%, based on the homologous and cluster analysis through enzyme digested PFGE electrophoresis. Those strains were highly homologous with the cholera epidemic strains identified in Hunan, Sichuan,Zhejiang, Shanghai and Hubei by PNCD, with the homology as 100% .</p><p><b>CONCLUSION</b>Four cholera outbreaks in Anhui province, 2012 were highly correlated with the outbreaks occurring in Hunan and Sichuan during the same time period, indicating that PNCD could effectively and quickly tracking down the source of infection on the cholera outbreaks and providing early warning of the situation.</p>

Molecular analysis on non-O1 and non-O139 Vibrio cholerae isolates / 中华流行病学杂志

Objective According to results from the two-month consecutive surveillance program in Maanshan,six suspected cases of non-O1 non-O139 Vibrio (V.) cholerae infection,were found that called for identification of pathogens as well as molecular-epidemiological analysis to determine the aggregation of the epidemic situation.Methods Biochemical and serotype identification,hemolysis test,and drug sensitive test were used to detect the drug resistance spectrum.Real-time PCR and conventional PCR were used to detect the presence of V.cholerae specific genes,virulent genes and its related genes,including ompW,ctx,tcpA,toxR,hlyA,zot,ace,rstR and g ⅢCTX.Pulsed-field gel electrophoresis (PFGE) was used to analyze the molecular type of strains.Results All the six isolates of non-O 1 non-O 139 V.cholerae were identified by biochemical and serologic tests,and appeared to be β hemolytic.Twelve out of the 14 kinds of drugs showed 100％ sensitive.All isolates were positive of ompW gene by real-time PCR,but negative for ctx,tcpA,zot,ace,rstR and gⅢ CTK.Five of the six isolates were positive for toxR and hlyA,except for strain 1001434446.All strains had different PFGE types,but two strains had similar types.All strains had a low similarity compared to the toxigenic V.cholerae.Conclusion Six cases ofnon-O1 and non-O139 nontoxigenic V.cholerae infection appeared in the same period.Along with epide(m)iological information,we noticed that these cases had a sporadic nature,but frequently appeared in the same area.We got the impression that public health measurements should be strengthened,with special attention paid to those diarrhea outbreaks caused by non-O 1 /non-O 139 strains since V.cholerae had appeared in low incidence.

Molecular epidemiology of enterohaemorrhagic Esacherichia coli O157 in some areas in China / 中华流行病学杂志

<p><b>OBJECTIVE</b>To understand the epidemiological characteristics of enterohaemorrhagic Escherichia coli (EHEC) O157 and to determine the degree of its genetic relations.</p><p><b>METHODS</b>Polymerase chain reaction (PCR) techniques and chromosomal DNA digested by restriction enzyme Xba I according to PulseNet directions by pulsed field gel electrophoresis (PFGE) method were applied to 300 E. coli O157 strains isolated from patients and animal sources from 1988 to 2005 from Henan, Jiangsu and Anhui provinces.</p><p><b>RESULTS</b>Very high prevalence of stx2 gene in EHEC O157:H7 strains isolated from some provinces of China was found and variation existed in some strains. We got 161 PFGE patterns from 300 strains. The stx2-producing strains could be clearly separated from stx2 variation-producing strains.</p><p><b>CONCLUSION</b>The variability of restriction enzyme-digestion patterns of O157 genomes suggested that the presence of some genomic diversity among the strains did exist.</p>

The firstly confirmed pregnant woman case of avian influenza A (H5N1) by etiological research in China / 病毒学报

To investigate the cause of death of a pregnant woman with undefined pneumonia reported from the People's Hospital of Tongling City in Anhui Province on November 8, 2005, the patient's tracheal aspirates and serum samples were collected and tested by RT-PCR and Real-time PCR to detect viral nucleic acids of HA of A/H5N1, A/H7N7, A/H9N1 and A/M. Tracheal aspirates were inoculated into special pathogen free (SPF) embryonated eggs for cultivation and identification of virus. The HA gene of the virus was sequenced and analyzed. Serum samples were tested by HI assay to detect antibody of H5N1. The results showed that HA gene of A/H5N1 virus and A/M were positive in tracheal aspirates by both PCR tests. The serum sample collected on Nov. 9 was A/M gene positive by Real-time PCR. The analysis of HA gene of A/AnHui/1/2005 sequence showed that the receptor specificity and the connecting peptide between HA1 and HA2 were still avian influenza origin. The HI antibody of H5N1 was negative at 7th, 8th, 9th d of disease onset. This undefined pneumonia case was confirmed as the first pregnant woman case of avian influenza (H5N1) virus infection by etiology in the mainland of China.

Study on a fatal pregnant woman died from by avian influenza (H5N1) / 中华流行病学杂志

<p><b>OBJECTIVE</b>To ascertain the causation of a pregnant woman with undefined pneumonia reported from the People's Hospital of Tongling city in Anhui province on November 2005.</p><p><b>METHODS</b>Epidemiological and clinical information of the case was collected from the keypersons close to the case and referring to the medical record. A medical observation was carried out on the close contacts of the case and sick or dead poultry. Tracheal aspirates being collected were tested by both RT-PCR and real-time PCR to detect viral nucleic acids of A/H5N1, and were inoculated into special pathogen free (SPF) embryonated hens' eggs.</p><p><b>RESULTS</b>The pregnant woman was found to have been contacted with the sick/dead poultry directly on the 4th day before onset of illness. All the 122 close contacts were healthy after a 10-day medical observation. The major clinical features of the case were viral pneumonia with rapidly developed leukopenia and lymphopenia. The progress to acute respiratory distress syndrome and multiple organ dysfunction syndromes was found at clinical presentation. HA and NA gene of A/H5N1 virus were positive. The 8 gene fragments of A/Anhui/1/2005 (H5N1) isolated from the tracheal aspirates had not carried genes from a human virus through reassortment, and the receptor-binding site of the hemagglutinin was polybasic cleavage site.</p><p><b>CONCLUSION</b>This was the first documented case of H5N1 infection in pregnant woman. The immunotolerant state of pregnancy might have predisposed to the fatal outcome of the patient.</p>

Molecular typing of the pathogenic Yersinia enterocolitica strains with pulsed field gel electrophores isolated in China / 中华流行病学杂志

<p><b>OBJECTIVE</b>To investigate the epidemiological and molecular typing features of the pathogenic Yersinia enterocolitica strains isolated in China,using pulsed field gel electrophoresis(PFGE) and standardized PFGE method as well as typing database of Yersinia enterocolitica.</p><p><b>METHODS</b>PFGE analysis was performed as Laboratory Directions for molecular subtyping of Salmonella by PFGE (PulseNet,USA) with some modifications and the results of PFGE were analyzed by BioNumerics soft (Version 4.0, Applied Maths BVBA, Belium).</p><p><b>RESULTS</b>114 O:3 Yersinia enterocolitica strains were typed by 25 patterns to have found that K6GN11C30012 (50 strains), K6GN11C30015(19 strains) and K6GN11C30016(10 strains) were the major patterns. K6GNllC30012 had 92.2% cluster similarity with K6GN11C30009-K6GN11C30023. This clone included 91.23% strains of 114 0:3 Yersinia enterocolitica strains. 51 0:9 Yersinia enterocolitica strains were typed by 14 patterns; K6GN11C90004 (22 strains) and K6GN11C90010 (13 strains)were the major patterns. K6GN11C90004 had 81.8% cluster similarity with K6GN11C90010 patterns. The major patterns of 0:3 and 0:9 serotypes were quite different.</p><p><b>CONCLUSION</b>O:3 Yersinia enterocolitica strains might originate from the same clone and had very few variation in different years and provinces but O:9 Yersinia enterocolitica strains from two different clones with some changes.</p>

Study on a monitoring program regarding leptospirosis in some fore-and-after flood-affected along large rivers in Anhui province / 中华流行病学杂志

<p><b>OBJECTIVE</b>The study was designed to find out the epidemic characteristics of leptospriosis and to develop effective intervention measures. The effects of floods on leptospriosis in some areas along Yangzi river and Huai river in Anhui province was also analysed.</p><p><b>METHODS</b>Study on serum epidemiology of leptospriosis was carried out from serous samples collected from native residents and animal hosts including isolation of pathogens at different phases (before,middle and after) and different monitoring spots,during the floods.</p><p><b>RESULTS</b>Infection rate with leptospriosis pathogen among native residents was 13.49% during the flood-period,much higher than 2.18% at post-flood (chi2 = 22.78, P < 0.01) stage, in the flood-affected areas along Yangzi river in 1998. The average rates of infection were 2.48% and 5.35% in affected and unaffected areas along Huai river respectively, in 2003.</p><p><b>CONCLUSIONS</b>There was full evidence that floods causing the epidemics of leptospriosis. However, the transmission of leptospriosis among people would depend on affecting factors as scales of floods, lasting time, coincidence between flood happening and epidemic season, immuno-protection level against leptospriosis among people and so on to a great extent. Factors as the magnitude of pathogens carried by various kinds of infectious sources were also important determinants affecting the nature, being epidemic or pandemic of leptospriosis. It was suggested that active surveillance network on the sources of infection and risk factors of leptospriosis should be developed for the control and prevention of the disease, in the flood-hit areas.</p>