Animals ; Brain-Derived Neurotrophic Factor ; Depression/drug therapy* ; Fluoxetine ; Mice ; Stress, Psychological ; Transcranial Magnetic Stimulation

Vibrio cholerae ; classification ; pathogenicity

OBJECTIVETo develop a TaqMan real-time PCR for the detection of Aeromonas hydrophila.

METHODSThe conserved region of major adhesion gene of Aeromonas hydrophila (aha) was used to design primers and TaqMan probe. A total of six concentration gradients for forward and reverse primers ranging from 200 -700 nmol/L were chosen, and four concentration gradients for probe ranging from 100 - 400 nmol/L were chosen. And then the concentration of primers and probe were optimized by ANOVA of completely randomized design respectively. The specificity of the established method was evaluated by using bacteria as contrast, including 45 strains Vibrio cholerae, 20 strains Vibrio parahaemolyticus, 10 strains Vibrio fluvialis, 4 strains Vibrio mimicus, 5 strains Vibrio vulnificus, 1 strain Vibrio alginolyticus, 1 strain Vibrio furnissii, 5 strains Salmonella, 10 strains Shigella and 2 strains Plesiomonas shigelloides. The sensitivity, bacterial sensitivity and DNA sensitivity included,were evaluated. The stool of healthy people was contaminated by Aeromonas hydrophila artificially, and the ability of the established TaqMan real-time PCR system for detection of Aeromonas hydrophila was also evaluated.

RESULTSThe cycle threshold (Ct) value deserved from 6 groups of primers concentration gradient was (x +/- s):20.69 +/- 0.33, 20.72 +/- 0.21, 20.81 +/- 0.12, 20.74 +/- 0.12, 20.51 +/- 0.16 and 20.69 +/- 0.11, respectively, and the concentration of forward primer and reverse primer was determined to be 200 nmol/L (F = 1.33, P = 0.28). The Ct value deserved from 4 groups of probe concentration gradient was (x +/- s):20.56 +/- 0.08, 20.82 +/- 0.05, 20.82 +/- 0.11 and 20.93 +/- 0.09, respectively, and the concentration of probe was determined to be 100 nmol/L (F = 5.26, P = 0.01). The bacterial sensitivity and DNA sensitivity were 80 CFU/ml and 100 fg/microl respectively, and the sensitivity to detect Aeromonas hydrophila from stool was 8 x 10(3) CFU/ml, which might be 8 CFU/ml after 8 hours' enrichment. No amplification was observed in the templates of other bacterial.

CONCLUSIONThe TaqMan real-time PCR method targeting the aha gene of Aeromonas hydrophila had a high sensitivity and specificity and might be used to detect Aeromonas hydrophila from pure bacterial and stool rapidly.

Aeromonas hydrophila ; genetics ; DNA Primers ; Genes, Bacterial ; Molecular Probes ; Polymerase Chain Reaction ; methods ; Sensitivity and Specificity ; Species Specificity

OBJECTIVETo understand the pollution rates of vibrio cholera (V. cholera) in different seafood, aquatic products and their circulatory processes, so as to help making measures for cholera control and prevention.

METHODSDifferent seafood, aquatic products and breed water specimen collected from 12 provinces of China were tested from July to September in 2005.

RESULTA total of 12 104 samples of seafood and aquatic products were tested and the average pollution rate of vibrio cholera was 0.52%. The positive isolate rate of turtle sample (1.72%) was the highest among all samples. The second higher isolated rate was 1.14% in water specimen of turtle breed pool. The positive rate of bullfrog was 0.50%. The percentage of toxin strains was 47.54% and 79.31% of them were isolated from turtle and water samples of turtle breed pool. The important sector of the pollution of vibrio cholera was in turtle breed pool (2.38%).

CONCLUSIONThe average pollution rate of vibrio cholera in seafood and aquatic products in 12 provinces of China was low. It should be very necessary to supervise the sanitation in turtle breed for controlling and preventing the vibrio cholera.

Animals ; China ; Female ; Fishes ; microbiology ; Food Contamination ; analysis ; prevention & control ; statistics & numerical data ; Male ; Seafood ; microbiology ; Seawater ; analysis ; Turtles ; microbiology ; Vibrio cholerae ; isolation & purification

OBJECTIVETo evaluate the utility of the cross-species screening strategy for investigating key molecule(s) involved in onset and progression of hepatocellular carcinoma (HCC).

METHODSHCC-related molecule data from our previous studies and in the literature were collected to establish a cross-species dataset. Tissue samples of HCC, non-HCC surrounding liver (para-HCC), and normal liver that were collected from humans, tree shrews and rats. The genes reported to have the most differential expression in HCC were verified by analyzing the mRNA and protein levels by reverse transcription-polymerase chain reaction (RT-PCR) and Western blotting, respectively.

RESULTSThe cross-species dataset of HCC-related molecules included four genes: epidermal fatty acid-binding protein (E-FABP), liver (L)-FABP, tyrosine a-ketoglutarate transaminase (TKT), and cytokeratin (CK8). In humans, E-FABP mRNA expression was significantly higher (P less than 0.05) in HCC (0.87+/-0.14 vs. para-HCC: 0.64+/-0.12 and normal liver: 0.67+/-0.07; F=20.910). Similar results were obtained in tree shrew (HCC: 0.87 +/- 0.25 vs. para-HCC: 0.73 +/- 0.19 and normal liver: 0.68+/-0.19; F=3.807) and rat (HCC: 0.97+/-0.22 vs. para-HCC: 0.78+/-0.16 and normal liver: 0.80 +/- 0.13; F=4.482). The Western blotting analyses revealed a similar statistically significant trend.

CONCLUSIONThe cross-species screening strategy for tumor genes may represent a feasible and convenient process of identifying key molecule(s) for human HCC. E-FABP may be a particularly crucial molecule for hepatocarcinogenesis.

Adult ; Aged ; Animals ; Carcinoma, Hepatocellular ; metabolism ; Case-Control Studies ; Epidermis ; chemistry ; Fatty Acid-Binding Proteins ; metabolism ; Female ; Humans ; Liver ; metabolism ; Liver Neoplasms ; metabolism ; Male ; Middle Aged ; Rats ; Tupaiidae ; metabolism

Bacterial Outer Membrane Proteins ; chemistry ; genetics ; physiology ; Bacteriophages ; chemistry ; Humans ; Receptors, Virus ; chemistry ; Vibrio cholerae ; virology

BACKGROUNDTyphoid/paratyphoid fever (TPF) is endemic in Guizhou. We conducted wavelet analysis and Spearman's rank correlation analysis to explore the impact of meteorological variations on TPF infection in Guizhou, in an attempt to assess the risk factors associated with TPF epidemics.

METHODSWe examined the association between TPF incidence in Guizhou and temperature, precipitation and relative humidity using 24 years of data from 1984 to 2007. Periodicities of TPF incidence and the impact of climate factors on the TPF were detected by Spearman's rank correlation and wavelet analysis,

RESULTSTemperature and precipitation with a 1-month lag were positively correlated with the monthly incidence of TPF. The multiyear incidence pattern of TPF in Guizhou was explicitly periodic. Moreover, the association and driving effect of precipitation on TPF were observed, and the results showed that the incidence of TPF in Guizhou had a closer correlation with precipitation than with temperature.

CONCLUSIONSSafe water supply is the key issue for TPF control in Guizhou. Moreover, climate variation might impact the enteric infections, which may inform policy assessment for TPF control in Guizhou.

China ; epidemiology ; Humans ; Incidence ; Paratyphoid Fever ; epidemiology ; Rain ; Temperature ; Typhoid Fever ; epidemiology

OBJECTIVETo investigate the serologic type, phage-biotype and toxic factor of Vibrio cholerae isolated from different sea products, analyze the relation between the Vibrio cholerae in sea products and cholera epidemiology, and provide references for forecasting cholera epidemic situation and drawing out a preventing plan.

METHODThe biotype of strains isolated was analyzed by using type and phage-biotype serological methods. The toxic gene was detected by PCR.

RESULTSThe constituent ratio of V. cholerae O139, Ogawa and Inaba were, respectively, 48.44%, 20.31% and 31.25% in 64 strains of V. cholerae. The result of phage-biotype showed that the 26 strains of V. cholerae O1 were all non-epidemic strains. The result of toxic gene detecting showed that positive rate of V. cholerae O139 was higher than those of Ogawa and Inaba.

CONCLUSIONThe positive rate of toxic gene in V. cholerae O139 was high and the V. cholerae O139 was mainly in turtle, breed aquatics water and crustacean, so these sea products were the important sectors in cholera prevention and control.

Animals ; Bacteriophage Typing ; DNA, Bacterial ; genetics ; Seafood ; microbiology ; Serotyping ; Vibrio cholerae ; classification ; genetics ; isolation & purification ; Vibrio cholerae O1 ; isolation & purification ; Vibrio cholerae O139 ; isolation & purification

OBJECTIVETo observe the hepatitis B virus (HBV) replication in the tree shrews that were inoculated with HBV at neonatal period.

METHODSSix new-born tree shrews were inoculated with human HBV positive serum. Blood samples and liver biopsies were collected at different time points after inoculation. The HBV infection markers were tested by nested polymerase chain reaction (nPCR), fluorescence quantitative polymerase chain reaction (FQ-PCR), Southern blot, ELISA and immunohistochemistry staining. The liver tissues were observed under electron and light microscope.

RESULTS48 weeks after inoculation, HBV DNA and HBV cccDNA were detected in the serum and liver samples of three animals (number 1, 2 and 6) by nPCR. The copy-numbers of HBV DNA detected by FQ-PCR in their serum and liver samples were 103 and-104/ml respectively,and the total DNA in 1microg liver tissue was 107-108. Southern blot indicated that HBV replication intermediates such as HBV cccDNA and HBV ssDNA was detectable in liver tissues. HBsAg was detected by ELISA, and immunohistochemical staining showed a gradual increase of HBsAg-positive liver cells. High copy number of HBV DNA and suspected HBV EM particles could be detected in the liver samples from one of the three animals that have survived more than 2 years after inoculation. The other three animals showed low HBV DNA copy number, and the rest of the signs of HBV infection were negative or transiently positive.

CONCLUSIONSNeonatal tree shrews can be infected with human HBV. HBV can replicate inside the liver cells of tree shrew.

Animals ; Animals, Newborn ; Biopsy ; DNA, Circular ; analysis ; blood ; DNA, Viral ; analysis ; blood ; Disease Models, Animal ; Hepatitis B ; etiology ; pathology ; virology ; Hepatitis B Surface Antigens ; blood ; Hepatitis B virus ; genetics ; physiology ; Humans ; Immunohistochemistry ; Liver ; pathology ; virology ; Polymerase Chain Reaction ; methods ; Tupaiidae ; Virus Replication

Objective To understand the biochemical characteristics and 16S rDNA genetic sequence evolution of strains isolated from diarrhea specimens so as to provide basis for classification and identification of Klebsiella pneumoniae. Methods Specimens were cultured using MacConkey and SS medium. All isolates were identified as K. pneumoniae by automated biochemical tests. DNA was extracted, 1500 bp fragments of the 16S rDNA gene were by amplified PCR and sequenced with K. pneumoniae 16S rDNA primer, after being cut. Fragments of 1000 bp overlapping sequences were analyzed by Blastn to confirm the identity of the isolates. A phylogenetic tree was constructed by PHYLIP process to analyze the 16S rDNA sequence of the isolated strain with other relative bacteria species in the GenBank databases. Results Among 113 specimens of infectious diarrhea, 25 K. pneumoniae strains were identified by biochemical tests, of which 21 subsp, pneumoniae and 4 subsp, ozaenae, no subsp, of rhinoseleroma were isolated. Strains of subsp, pneumoniae were found having nature of resistance. All isolates were resistant to penicillin G and susceptible to polymyxin with some strains were resistant to Nitrofurantoin, Cephalothin, Kanamycin, Tobramycin. After searching in GenBank of 16S rDNA, strains biochemical identified as subsp, ozaenae shared high similarity with Salmonella strains and other intestinal bacteria. 16S rDNA phylogenetie analysis could be used to confirm subsp, pneumoniae, but could not separate other subspecies of K. pneumoniae completely. Conclusion 16S rDNA phylogenetic analysis useful in identifying and classifying K. pneumoniae.