Species identification of Triculinae based on COI gene segment, Fujian Province / 中国人兽共患病学报

The aim of the study is to evaluate the utility value of species identification of Triculinae based on COI gene.Triculinae-like samples were collected from different places in Fujian Province.After classification based on morphology characters,genomic DNA was extracted from collected samples.Then the segments of COI gene were amplified and sequenced for taxonomy annotation and phylogenetic analysis.Eleven samples were annotated as Gammatricula (identities:88.96％-97.82％),the other two were annotated as Tricula wumingensis (identity:87.08％) and Neotricula apart (identity:88.55％),respectively.In most cases (12 out of 13),there was a difference between results based on different classification methods on a genus level.The alignment of COI gene segment is sufficient for preliminary identification of Triclulinae at family level.However,it is need further study in species identification of Triclulinae at genus level.

Establishment and application of a loop-mediated isothermal amplification method for rapid diagnosis of Vibrio cholerae / 南方医科大学学报

<p><b>OBJECTIVE</b>To establish a loop-mediated isothermal amplification (LAMP) method for rapid diagnosis of Vibrio cholerae.</p><p><b>METHODS</b>Based on the ompW nucleic sequence of Vibrio cholerae, a pair of primers was designed for LAMP. The reaction conditions were optimized, and the specificity, sensitivity, and practicability of LAMP were tested using 47 bacterial strains and simulated contaminated sites.</p><p><b>RESULTS</b>The results of viable bacterium count showed that LAMP was capable of detecting Vibrio cholerae at a level as low as 1.6x10(2) cfu/ml. The minimal detectable concentration was 1.6+10(3) cfu/ml for simulated contaminated samples such as feces and seawater, and 1.6+10(4) cfu/ml for contaminated milk. All the 21 strains of Vibrio cholerae yielded positive results in LAMP, and the 26 strains of other bacteria all showed negative results, with a detection specificity of 100%.</p><p><b>CONCLUSION</b>The established LAMP method has high specificity and sensitivity for detecting Vibrio cholerae and is applicable in field monitoring and epidemiological study of Vibrio cholerae.</p>

Antimicrobial resistance of clinical isolates of Stenotrophomonas maltophilia / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the antimicrobial resistance of clinical isolates of Stenotrophomonas matophilia (SMA) and the mechanisms of their drug resistance.</p><p><b>METHODS</b>Disc diffusion method (NCCLS) was used to detect the resistant patterns of 88 initial SMA isolates resistant to 12 antibiotics isolated from a local hospital in the past 4 years. PCR was used to detect the 7 aminoglycosides modifying enzymes genes (AME) against amikacin and gentamicin. Metal-beta-lactamases (MBLs) were screened by synergic method, and extended-spectrum beta-lactamases (ESBLs) were detected by double-disk synergy test.</p><p><b>RESULTS</b>The resistance rates of the SMA isolates were 0%-9.7% to minocycline, 12.5%-22.6% to ticarcillin-clavulanic acid, 12.5%-28.6% to levofloxacin, 18.8%-33.3% to doxycycline, 18.8%-40% to sulfamethoxazole compound, 50%-65.7% to ciprofloxacin, 50%-66.7% to cehazindme, 54.8%-66.7% to amikacin, 75%-100% to gentamicin, 81.3%-100% to piperacillin, 87.5%-100% to aztreonam and 93.5%-100% to imipenem. Aac(3)-I and ant(4')-II were not detected in these strains. The positive rates of the other 5 AME genes of aac(3)-II, ant(2'')-I, aac(6')-I, aac(3)-III, aac(3)-IV were 2.3%, 5.7%, 8%, 10%, and 10%, respectively. SMA strains producing ESBLs were found at the rate of 38.6%; 25% of the strains were MBL-producing, and 13.6% produced both ESBLs and MBLs.</p><p><b>CONCLUSION</b>Most of the SMAs we isolated are multidrug-resistant through various mechanisms. The choice of antibiotics should be made according to the susceptibility results.</p>

An epidemiological investigation of bats carrying SARS-CoV in Guangzhou and its vicinity / 南方医科大学学报

<p><b>OBJECTIVE</b>To detect serve acute respiratory syndrome-associated coronavirus (SARS-CoV) and SARS-like-CoV in fruit bats captured in Guangzhou and its vicinity.</p><p><b>METHODS</b>Totally 927 bats of 9 species (Cynopterus sphinx, Rousettus leschenaulti, Miniopterus schreibersi, Hipposideros pratti, Rhinolophusasinicus, Scotophilusakuhlii, Hipposideros Pomona, Rhinolophus affinis, and Rhinolophus pusillus) captured in Guangzhou and its vicinity from September 2004 to November 2005 were available for this investigation, from which 3,043 samples (813 throat swasb, 524 sera, 853 lung tissues and 853 colorectal tissue specimens) were obtained. SARS-Cov and SARS-like-CoV were detected in these specimens using diagnostic kit for novel coronavirus N protein (ELISA), SARS-CoV Virus RNA detection kit, fluorescence PCR, Genchip, RT-PCR and cell isolation culture methods.</p><p><b>RESULTS AND CONCLUSION</b>No SARS-CoV and SARS-like-CoV were detected in the 3043 samples, indicating the current absence of SARS-CoV and SARS-like-CoV in the bats captured in Guangzhou and its vicinity.</p>