Some medical staff positive for serum SARS coronavirus antibody IgG have only mild symptoms / 南方医科大学学报

<p><b>OBJECTIVE</b>To identify patients with SARS coronavirus infection who have only mild symptoms.</p><p><b>METHOD</b>Enzyme-linked immunosorbent assay was employed to detect serum antibody against SARS coronavirus in the lysate of whole SARS coronavirus from 19 SARS patients and 200 medical staff members without obvious SARS symptoms after possible exposure to the virus during routine medical practice.</p><p><b>RESULTS</b>Serum IgG antibody against SARS coronavirus was detected in all the 19 SARS patients, and among the 200 staff members, 20 (10%) were found positive for the antibody but with no obvious or only mild symptoms.</p><p><b>CONCLUSION</b>Serum IgG antibody against SARS coronavirus is positive in a small proportion (around 10%) of the medical staff members exposed to the virus in our hospital, but may not cause obvious symptoms, suggesting SARS coronavirus infection might in some cases have mild or even no clinical manifestations.</p>

Development and application of a new hepatitis C virus genotyping method with polymerase chain reaction-reverse blot dot technique / 中华流行病学杂志

<p><b>OBJECTIVE</b>Using polymerase chain reaction-reverse blot dot (PCR-RDB) technique to establish a new method for hepatitis C virus (HCV) genotyping and to study the distribution of HCV genotypes in Foshan area.</p><p><b>METHODS</b>HCV primers and probes were designed in 5'-untranslated region (nt-1-nt-299) of HCV. HCV RNA in serum was isolated and purified, and its cDNA was obtained by reversed transcription. Nested PCR using biotin-labelled primers, was done. PCR products were hybridized with immobilized specific probes (genotype 1a to 3b) on Biodyne C membrane to genotype HCV by color development while adding POD and TMB. A certain judgment could be made according to the position of color reaction. The reliability of this new method was verified by sequencing. HCV RNA levels in serum were determined by real time fluorescent quantitative (FQ)-PCR. 60 FQ-PCR-positive HCV sera from Foshan area were genotyped using this assay.</p><p><b>RESULTS</b>All 60 sera could be successfully genotyped by PCR-RBD. 50 (83.3%) cases were found to be genotype 1b, 2 (3.3%) as genotype 1a and 2 (3.3%) as genotype 2a while 5 (8.0%) to be mixture of genotype 1a and 1b, and 1 (1.7%) to be mixture of genotypes 1b and 2a. No genotypes 2b, 3a and 3b were found. The results of PCR-RDB genotyping methods coincided with sequence analysis.</p><p><b>CONCLUSION</b>Newly established HCV genotyping system was proved to be sensitive, specific, precise and economic, thus suitable for clinical and epidemiologic studies. The results of HCV genotyping showed that genotype 1b was the predominant genotype in Foshan area.</p>

Establishment of a new HBV genotyping method with PCR-RBD and its application / 中华肝脏病杂志

<p><b>OBJECTIVE</b>Using PCR-RDB to establish a new method for HBV genotyping, and to survey the distribution of HBV genotypes in the Foshan area.</p><p><b>METHODS</b>Biotin-labeled primers for amplification of HBV region X (nt1550-1789) were used to amplify extracted HBV DNA. HBV was genotyped by hybridization of the PCR products with immobilized specific probes (genotype A to F) on C membrane. Color development was achieved by adding POD and TMB. A judgment was made according to color reactions. The reliability of this new method was verified by gene sequencing. 300 samples of HBV DNA-positive sera from the Foshan area were genotyped using this assay.</p><p><b>RESULTS</b>Of the 300 sera genotyped by PCR-RBD, 147 (49.0%) cases were genotype B, 136 (45.3%) were genotype C, 1 (0.3%) genotype D, and 12 (4.0%) were mixtures of genotype B and C, and 4 (1.3%) were mixtures of genotype C and D. No genotype A, E or F were found. The results of PCR-RDB genotyping were consistent with the results obtained with sequence analysis.</p><p><b>CONCLUSION</b>This newly established HBV genotyping system proved to be sensitive, specific, precise and economic, and should be suitable for clinical practice and epidemic study. The results of HBV genotyping show that genotype B and C are the predominant genotypes in the Foshan area.</p>

Farm compost polluted water may induce pharyngo-esophageal, gastric and liver carcinoma in the chicken / 中华肿瘤杂志

<p><b>OBJECTIVE</b>To study farm compost polluted water that may induce pharyngo-esophageal, gastric and liver carcinoma in chickens.</p><p><b>METHODS</b>280 chickens were randomized into 4 groups: experiment group 100 chickens fed with compost water + NaNO(2) by stomach tube. The other 180 were evenly randomized into 3 control groups (60 each), fed with compost water, NaNO(2) and tap water in the same way. The farm compost was prepared with corn stalks, rice straws, excreta of men and livestock. The compost water, after being nitrosified and acidified, was fed through stomach tube 5 - 7.5 ml/session, twice a week. Besides, a solution consisting of the respective formula of each group added with 3 - 4 L water with pH adjusted to 3 - 4 by 1N HCL was given ad lib to all chickens in each group for 26.5 months.</p><p><b>RESULTS</b>In the experiment group, there were pharyngo-esophageal carcinoma 16 (16.3%), gastric adenocarcinoma 5 (10.4%) and liver carcinoma 3 (6.3%), in contrast to none in the 3 control groups, showing significant differences (P < 0.01, P < 0.01, P < 0.05).</p><p><b>CONCLUSION</b>Successful simulation of the layout of esophageal carcinoma high morbidity area and the mimic of chicken gastric fluid strongly support our compost etiological hypothesis that the nitrosified and acidified compost water are carcinogenic, very well causing esophageal, gastric and liver carcinoma.</p>