Drug resistance and molecular epidemiology of Shigella isolated from children with diarrhea / 中华儿科杂志

<p><b>OBJECTIVE</b>To investigate the prevalence and antibiotic resistance of Shigella isolated from children with diarrhea for the guidance of clinical treatment and prevention and control of bacillary dysentery.</p><p><b>METHOD</b>A total of 156 strains of Shigella were isolated from feces of children with diarrhea in Zhejiang Xiaoshan Hospital from January 2008 to December 2010. The antimicrobial resistance of the strains was detected by disk diffusion method and the extended-spectrum beta-lactamases (ESBLs) in these isolates were determined using phenotypic confirmatory test; the isolates of ESBLs producing Shigella sonnei were analyzed by REP-PCR.</p><p><b>RESULT</b>Among 156 strains of Shigella isolated, the most common groups were Shigella sonnei (130 strains, accounting for 83.3%) and Shigella fleaneri (26 strains, accounting for 16.7%), and 81 (51.9%) strains were identified as ESBLs producers, and the positive rates in 2008, 2009 and 2010 were 32.0%, 41.4% and 59.8%, respectively. The results of antibiotic susceptibility test displayed that the resistance rates of ESBLs producing Shigella to ampicillin, cotrimoxazole, cefotaxime, piperacillin were higher than 90%. However, the resistance rates to cefepime, ceftazidime, levofloxacin and ciprofloxacin were low; The resistance of ESBLs producing strains to piperacillin (100% vs. 77.3%), cefotaxime (100% vs. 0), ceftazidime (14.8% vs. 0), cefepime (28.4% vs. 0), cotrimoxazole (95.1% vs. 86.7%) was significantly higher than that of non-ESBLs producing strains (χ(2) = 20.605, 156.000, 12.037, 24.979, 45.040, respectively; P < 0.05). No isolate was resistant to piperacillin/tazobactam and imipenem. There were 7 genotypes among 74 ESBLs producing Shigella sonnei, respectively type A (50), type B (12), type C (8), type D (1), type E (1), type F (1), and type G (1).</p><p><b>CONCLUSION</b>The isolation rate of ESBLs-producing isolate was high in Shigella from pediatric patients with diarrhea, and the number is going up year by year, and these ESBLs producing Shigella sonnei strains in genotype A are dominant in recent years, Piperacillin/tazobactam is the drug of choice for children with ESBLs producing Shigella infection.</p>

Etiological analysis of influenza surveillance data in Xuzhou from 2005 to 2011 / 中华实验和临床病毒学杂志

<p><b>OBJECTIVE</b>To investigate the prevalence and subtypes of influenza viruses in Xuzhou city from 2005 to 2011 and to provide the scientific supports for influenza prevention and control in this religion.</p><p><b>METHODS</b>The throat swab samples were collected from the influenza-like cases from national influenza like illness sentinel hospital in Xuzhou. The samples were used for influenza virus isolation and identification, sent on the national flu center to confirm according to the "national influenza surveillance program" and "influenza virus and experimental technology".</p><p><b>RESULTS</b>From Oct. 2005 to Dec. 2011, a total of 9561 swab specimens were collected in which 1152 strains were identified for influenza viruses with total isolated rate of 12.0%. Among these strains, 708 strains were A1 (H1N1) subtype (14.2%), 466 strains were A3 (H3N2) subtype (40.5%), 78 strains were new H1N1 subtype (6.8%), 362 strains were BV (Victoia) subtype (31.4%) and 82 strains were BY (Yamagate) subtype (7.1%). The top detection rate (25.9%) arose in 2007, secondary detection rate (17.4%) occurred at 2009 and the lowest one (2.3%) appeared in 2011. From the winter of 2005 to the spring of 2006 A1 (H1N1) subtype had appeared as predominant strains but in the winter of 2006 the predominant strains were BV subtype. It changed to A3 subtype in 2007 to 2009 and the other three dominant strains were A1, BV and BY in 2008. In the winter of 2009, both A3 (H3N2) and new H1N1 subtype were predominant strains. BV subtype was predominant strains in 2010 to 2011. The prevalence of A3 subtype appeared in all the year while prevalence of BV only arose in the spring and winter. So the detection rate was high in January (34.4%) but low in August (2.2%). The influenza population is correlated with age, the highest detection rate arose in 5-age group and the lowest detection rate appeared in 25-age group.</p><p><b>CONCLUSION</b>Influenza subtype A1, A3, New H1N1 are all appeared as predominant strains in Xuzhou city from 2005 to 2010. Besides, the prevalence of BV subtype is stronger in recently.</p>

Analysis on pathogen detection for 53 influenza outbreaks / 中华实验和临床病毒学杂志

<p><b>OBJECTIVE</b>In order to provide a scientific basis for influenza prevention and control, analyzing the epidemic characteristics and laws of influenza outbreaks in Xuzhou area during 2005-2011.</p><p><b>METHOD</b>Using fluorescent-PCR method to detect influenza virus nucleic acid on Nasopharyngeal swab specimens collected from influenza outbreak cases during 2005-2011 and fast classifying influenza virus A1 (H1N1), A3 (H3N2), new H1N1 BV (Victoria) and BY (Yamagate) on subtypes. At the same time, isolating the influenza virus with MDCK cells, and sending them to the National Influenza Center for review, after the preliminary identification of the isolated influenza virus.</p><p><b>RESULTS</b>During 2005-2011, there are 53 influenza outbreaks in Xuzhou area, which caused by influenza virus subtype BV accounting for 26.42% (14/53), A3 accounting for 49.1% (26/53), A3 and A1 mixture accounting for 3.77% (2/53) and the new H1N1 accounting for 20.75% (11/53). The outbreaks in 2007 and 2009 mainly caused by A3, and show that the winter spring (January) and summer autumn (September) as two popular peaks during 2005-2011; BV mainly causes the outbreaks from Feb. to Jun.</p><p><b>CONCLUSION</b>In Xuzhou area, since the winter of 2005, influenza virus subtype BV, the A3, and new H1N1 has alternately as mainly predominant strain, caused local influenza outbreaks. In which BV has increased trend year by year during 2005-2011. The students in primary and secondary schools are the major crowd of influenza outbreaks. Fluorescent-PCR detection methods could be a preferred method for reliable and rapid diagnostic of epidemic influenza outbreaks.</p>

Research progress in hirudin fusion protein--review / 中国实验血液学杂志

Natural hirudin extracted from the secretion of medical leech salivary gland is a single-chain peptide containing 65 aminoacid residues with molecular weight of 7000 D, and exists in three isomers of HV1, HV2 and HV3. Hirudin possesses three disulfide bridges forming the structure of core cyclic peptides, which binds to the catalytic site of thrombin so as to inhibit the catalysis of thrombin. Its c-terminus rich in acidic aminoacid residues possesses hydrophilicity, and is free on the molecular surface, and can bind with fibrin recognition site of hirudin. The minimal segment of 12 - 16 C-terminal acidic residues keeps the minimal activity of anti-thrombosis. Thus, hirudin, as a potent and specific inhibitor of thrombin, can be used to protect from and to treat clinically thrombosis. As it has some disadvantages such as short half-life, bleeding side-effect and mono-function, and so on, hirudin has been fused with some other functional proteins in recent years. The obtained fusion proteins can prolong the half life of hirudin, or relieve it bleeding side effect, or bring new functions, such as thrombolysis, inhibiting the platelet aggregation, targeting specifically. The research progress in hirudin fusion protein was summarized in this review.