Detection and characterization of three zoonotic viruses in wild rodents and shrews from Shenzhen city, China.

Diverse species of rodents and shrews, which are abundant worldwide, harbor a variety of viruses; some of these are closely related to human viruses and possess zoonotic potential. Previously studies have demonstrated that the mammarenavirus and hantavirus carried by rodents or shrews could cause diseases in human population. To determine the distribution of zoonotic viruses in Shenzhen city, the major city in southern China with a high population density, we analyzed 225 rodents (Rattus norvegicus and Rattus flavipectus) and 196 shrews (Suncus murinus) from urban and rural districts for the presence of mammarenavirus, hantavirus, and hepatitis E virus (HEV) by RT-PCR targeting the conserved regions. The infection rates for mammarenavirus, hantaviruses, and HEV in rodents and shrews were 3.56%, 6.89%, and 1.66%, respectively. Partial genome fragment analysis indicated that mammarenavirus and hantavirus strains had more than 90% and 99% nucleic acid identity with Cardamones virus and Seoul virus, respectively, which cause diseases in humans. Although the present HEV strains identified are typically found worldwide, phylogenetic analysis demonstrated a divergence of 16%. To our knowledge, the present work is the first report of the prevalence of mammarenavirus, hantaviruses, and rat HEV strains in rodents and shrews from Shenzhen city, China. Our findings highlight the zoonotic potential of rodent- and shrew-borne mammarenavirus and hantavirus, and the biodiversity of rat HEV isolates in Shenzhen city. The present work suggests that utilization of good hygiene habits is important to minimize the risk of zoonosis.

Optical detection of plasma chitotriosidase activity in healthy Chinese children using fluorescence spectrophotometry.

BACKGROUND: Plasma chitotriosidase had been proposed as a biochemical marker of macrophage accumulation in several lysosomal storage disorders. The selection of wavelength and possible interferences and errors have not yet been explored in the assay of chitotriosidase activity. We evaluated the feasibility of measurement of plasma chitotriosidase activity by fluorescence spectrophotometry and established pediatric reference values for earlier diagnosis of related diseases. METHODS: We assayed plasma chitotriosidase activity in 104 healthy Chinese children by a fluorometric approach which combines 3-dimension scan spectra, wavelength scan spectra, time scan spectra and fluorescence intensity analysis. RESULTS: The optimal excitation wavelength and emission wavelength were 358 and 448 nm, respectively. A change of enzyme activity over time was observed fluorometrically, The reference value was 13.04+/-4.94 nmol/ml/h (12.45+/-4.37 nmol/ml/h for boys and 14.04+/-3.99 nmol/ml/h for girls). CONCLUSIONS: We present an integrated application of the fluorescence spectrophotometry as an ideal tool to determine enzymatic activity with 4-methylumbelliferyl triacetylchitotrioside as labeled substrates in clinical laboratory. The function of 3D scan was proved powerful in determination of plasma chitotriosidase activity. The establishment of plasma chitotriosidase activity reference pediatric values was potentially useful for the evaluation of all related diseases.