2006年5月以来,我国部分猪场暴发了一种以高热、高发病率和高死亡率为特征的传染性疾病,经病原分离及分子流行病学分析证明是由一种带有nsp2部分缺失的、对猪呈高致病性的猪繁殖与呼吸综合征病毒(Porcine reproductive and respiratory ...2006年5月以来,我国部分猪场暴发了一种以高热、高发病率和高死亡率为特征的传染性疾病,经病原分离及分子流行病学分析证明是由一种带有nsp2部分缺失的、对猪呈高致病性的猪繁殖与呼吸综合征病毒(Porcine reproductive and respiratory syndrome virus,PRRSV)引起的。本实验参考GenBank发表的以及本实验室分离鉴定的PRRSV的nsp2基因序列,在nsp2缺失区的两端的保守区设计并合成了一对引物,建立了一种PRRSV的RT-PCR检测方法。该方法扩增高致病性PRRSV基因组时可获得230bp的片段,扩增经典型PRRSV时则获得320bp的片段,根据RT-PCR产物大小可将二者区分开来。通过大量临床病料的检测,并配合PCR产物测序验证,结果表明该方法简便、快速、特异,可以鉴别高致病性PRRSV,为进一步的PRRS流行病学研究提供了重要的技术手段。展开更多
According to the published genome sequences of Porcine circovirus type 2 (PCV2) and Porcine reproductive and respiratory syndrome virus (PRRSV), primers were designed and PCR, RT-PCR were set up for the detection of P...According to the published genome sequences of Porcine circovirus type 2 (PCV2) and Porcine reproductive and respiratory syndrome virus (PRRSV), primers were designed and PCR, RT-PCR were set up for the detection of PCV2 and PRRSV, respectively. With the established methods, 38 clinical samples from the respiratory disease pigs were detected for the presence of PCV2 and PRRSV. The results demonstrated that 22 samples were positive for PCV2, 27 samples were positive for PRRSV and among the above positive samples, 18 samples were positive for both viruses. The data obtained in the present study indicated that PCV2 and PRRSV maybe play an important role in the course of the development of respiratory diseases.展开更多
The appearance of severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)variant Omicron(B.1.1.529)has caused panic responses around the world because of its high transmission rate and number of mutations.This rev...The appearance of severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)variant Omicron(B.1.1.529)has caused panic responses around the world because of its high transmission rate and number of mutations.This review summarizes the highly mutated regions,the essential infectivity,transmission,vaccine breakthrough and antibody resistance of the Omicron variant of SARSCoV-2.The Omicron is highly transmissible and is spreading faster than any previous variant,but may cause less severe symptoms than previous variants.The Omicron is able to escape the immune system’s defenses and coronavirus disease 2019 vaccines are less effective against the Omicron variant.Early careful preventive steps including vaccination will always be key for the suppression of the Omicron variant.展开更多
BACKGROUND:Hepatocellular carcinoma (HCC) is characterized by a multi-cause,multi-stage and multi-focus process of tumor progression.Its prognosis is poor and early diagnosis is of utmost importance.This study was und...BACKGROUND:Hepatocellular carcinoma (HCC) is characterized by a multi-cause,multi-stage and multi-focus process of tumor progression.Its prognosis is poor and early diagnosis is of utmost importance.This study was undertaken to investigate the dynamic expression of oncofetal antigen glypican-3 (GPC-3) and GPC-3 mRNA in hepatocarcinogenesis and to explore their early diagnostic value for HCC.METHODS:A hepatoma model was induced in male Sprague-Dawley rats with 0.05% 2-fluorenylacetamide and confirmed by hematoxylin and eosin staining and gamma-glutamyltransferase (GGT) expression.Total RNA was purified and transcribed into cDNA by reverse transcription.Fragments of the GPC-3 gene were amplified by nested RT-PCR,and confirmed by sequencing.GPC-3 was analyzed by immunohistochemistry,Western blotting or ELISA.RESULTS:Positive GPC-3 expression showed as brown granule-like staining localized in the cytoplasm.Histological examination of hepatocytes revealed three morphological stages of granule-like degeneration,atypical hyperplasia (precancerous),and cancer formation,with a progressive increase of liver total RNA and GGT expression.The incidence of liver GPC-3 mRNA and GPC-3,and serum GPC-3 was 100%,100% and 77.8% in the HCC group,100%,100%,and 66.7% in the precancerous group,83.3%,83.3%,and 38.9% in the degeneration group,and no expression in the liver or blood of the control group,respectively.There was a positive correlation between liver GPC-3 mRNA and total RNA level (r=0.475,P<0.05) or liver GPC-3 (r=1.0,P<0.001) or serum GPC-3 (r= 0.994,P<0.001).CONCLUSION:Abnormal oncofetal antigen GPC-3 and GPC-3 mRNA expression in hepatocarcinogenesis may be promising molecular markers for early diagnosis of HCC.展开更多
文摘According to the published genome sequences of Porcine circovirus type 2 (PCV2) and Porcine reproductive and respiratory syndrome virus (PRRSV), primers were designed and PCR, RT-PCR were set up for the detection of PCV2 and PRRSV, respectively. With the established methods, 38 clinical samples from the respiratory disease pigs were detected for the presence of PCV2 and PRRSV. The results demonstrated that 22 samples were positive for PCV2, 27 samples were positive for PRRSV and among the above positive samples, 18 samples were positive for both viruses. The data obtained in the present study indicated that PCV2 and PRRSV maybe play an important role in the course of the development of respiratory diseases.
文摘The appearance of severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)variant Omicron(B.1.1.529)has caused panic responses around the world because of its high transmission rate and number of mutations.This review summarizes the highly mutated regions,the essential infectivity,transmission,vaccine breakthrough and antibody resistance of the Omicron variant of SARSCoV-2.The Omicron is highly transmissible and is spreading faster than any previous variant,but may cause less severe symptoms than previous variants.The Omicron is able to escape the immune system’s defenses and coronavirus disease 2019 vaccines are less effective against the Omicron variant.Early careful preventive steps including vaccination will always be key for the suppression of the Omicron variant.
基金supported by grants-in-aid from the Projects of Medical Science (H200925)the Natural Science Foundation of Jiangsu Province,China (BK2008187)
文摘BACKGROUND:Hepatocellular carcinoma (HCC) is characterized by a multi-cause,multi-stage and multi-focus process of tumor progression.Its prognosis is poor and early diagnosis is of utmost importance.This study was undertaken to investigate the dynamic expression of oncofetal antigen glypican-3 (GPC-3) and GPC-3 mRNA in hepatocarcinogenesis and to explore their early diagnostic value for HCC.METHODS:A hepatoma model was induced in male Sprague-Dawley rats with 0.05% 2-fluorenylacetamide and confirmed by hematoxylin and eosin staining and gamma-glutamyltransferase (GGT) expression.Total RNA was purified and transcribed into cDNA by reverse transcription.Fragments of the GPC-3 gene were amplified by nested RT-PCR,and confirmed by sequencing.GPC-3 was analyzed by immunohistochemistry,Western blotting or ELISA.RESULTS:Positive GPC-3 expression showed as brown granule-like staining localized in the cytoplasm.Histological examination of hepatocytes revealed three morphological stages of granule-like degeneration,atypical hyperplasia (precancerous),and cancer formation,with a progressive increase of liver total RNA and GGT expression.The incidence of liver GPC-3 mRNA and GPC-3,and serum GPC-3 was 100%,100% and 77.8% in the HCC group,100%,100%,and 66.7% in the precancerous group,83.3%,83.3%,and 38.9% in the degeneration group,and no expression in the liver or blood of the control group,respectively.There was a positive correlation between liver GPC-3 mRNA and total RNA level (r=0.475,P<0.05) or liver GPC-3 (r=1.0,P<0.001) or serum GPC-3 (r= 0.994,P<0.001).CONCLUSION:Abnormal oncofetal antigen GPC-3 and GPC-3 mRNA expression in hepatocarcinogenesis may be promising molecular markers for early diagnosis of HCC.
