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Objective To investigate the epidemiology of BDV infection in Yili horses and Yili donkeys and to analyze phylogenetic source of BDV in Yili area, Xinjiang. Methods We established fluo- rescence quantitative nested RT-PCR to detect BDV p24 segment in peripheral blood mononuclear cells (PBMCs) of 518 Yili horses and 206 Yili donkeys in Yili area, Xinjiang. Positive products were validated by detecting BDV p40 segment and plasmid to preclude the contamination, and were sequenced to analyze the homology of gene sequence, amino acid sequence and phylogenetic tree. Results The positive rates of BDV infection in PBMCs of 518 Yili horses and 206 Yili donkeys were 0.97% and 1.94%, respectively. The results of BDV p40 segment verification were positive in all of the samples of BDV p24 positive. All the samples tested were not contaminated by plasmid. There was a homology of the gene sequence of positive PCR samples with strain He/80. And the gene sequence revealed more than 93% identical to H1766 and strain V. Conclusion Our study suggested BDV natural infection in Yili horses and Yili donkeys. The en- demic BDV had a high degree of identity to strain He/80.
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Objective To establish nucleic acid testing techniques for detecting Nipah virus (NiV) and Hendra virus (HeV), and to test the NiV and HeV in peripheral blood collected from domestic pigs, cows and goats in Chongqing. Methods Peripheral blood samples of 580 domestic pigs, 250 cows, 180 goats were collected from Chongqing since June 2007 to June 2008. The lymphocytes were separated by density gradient centrifugation and total RNA was extracted using Trizol method for detection of NiV and HeV with one-step real-time RT-PCR. Sequence identification and analysis were performed for positive PCR prod-ucts. Virus isolation and culture were adopted for positive samples, and epidemiologic reports were submit-ted. Results Nucleic acid detections searching for NiV and HeV were successfully performed in animal blood samples collected from Chongqing. "Takeoff points" were not found in fluorescence amplification curves of all samples. Curves kept the same slope, and assays were judged as negative. Conclusion Until now, Neither NiV or HeV infection has been found in domestic animals blood samples collected from Chongqing, which suggest a lower possibility of outbreaks of Nipah disease and Hendra disease in Chongqing in the near future.
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Objective:It intended to examine whether there is BDV infection in the human tumor tissues of central nervous system in China and investigate the correlation between BDV infection and tumom of central nervous system.Methods:Nested reverse transcriptase polymerase chain reaction(nRT-PCR)and fluorescence quantitative polymerase chain reaction(FQ-PCR)was used to detect the BDV p24 fragments in 60 samples of human tumor tissues of central nervous system and 14 normal brain tissues.Results:The study indicated the positive rate of the BDV p24 fragment in human tumor tissues of the central nervous system (6.67%)was higher than that in normal brain tissues(0),but no statistical significance(P>0.05).Concluswn:It suggests that the BDV infection is present in the human tumor tissues of central nervous system in China.while the sample size wa.sn't large enough and we could not certify the possible correlation between BDV infection and cenfral nervous system tumors.
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BACKGROUND: Neural stem cells are always derived from fetal rats and adult rats, and it is complex to isolate the cells by cell culture.OBJECTIVE: To study a convenient and effective method for the isolation and the culture of neural stem cells in neonatal rats.DESIGN, TIME AND SETTING: An observation study based on cells was carried out in the Chongqing Medical University (Chongqing, China) from October 2006 to March 2007.MATERIALS: Wistar neonatal rats of 1-3 days old.METHODS: Subsequent to trypsin digestion, primary culture of the cells was performed in serum-free suspension culture medium. Then the cells were induced to incubate in DMEM/F12 containing 0.10 volume fraction of fetal bovine serum. MAIN OUTCOME MEASURES: Phase contrast microscopy was employed to observe the growth of neural stem cells and the morphology of the differentiated cells. Neural stem cells and the differentiated neurons were identified using indirect immunofluorescence cytochemistry, as well as expression of gilal fibrillary acidic protein. Moreover, the proliferation of the BrdU-labeled neural stem cells was also investigated.RESULTS: The neural stem cells isolated from neonatal rat brains had the potential of serial passage and proliferation, besides, they express neuroepithelial stem cell protein (nestin) and differentiate into neurons, astrocytes and oligodendrocytes.CONCLUSION: Neural stem cells can be harvested from neonatal rat brains at a large scale, and they maintain their undifferentiated features and have the capacity of self-renewal and pluripotentiality.