Research Aims: Obesity and type 2 diabetes are known to be associated with increased risk of various types of cancer. However, the molecular biological mechanism of how the risk of cancer is increased in obesity or ty...Research Aims: Obesity and type 2 diabetes are known to be associated with increased risk of various types of cancer. However, the molecular biological mechanism of how the risk of cancer is increased in obesity or type 2 diabetes is not known. The aim this research is to investigate if the decreased expression of p27Kip1, a cell cycle repressor protein, plays a central role in this mechanism. Research Methods, Previous Studies and Theoretical Backgrounds: It is well known that the expression of p27Kip1 is increased by numerous nutritional or chemopreventive anti-cancer agents. But it has never been known that the expression of p27Kip1 could be decreased, rather than increased, and the risk of cancer could be increased, rather than decreased. This problem was solved recently and this new analytical method was used in this study. Results: 1) The expression of p27Kip1 was indeed significantly decreased in human obese type 2 diabetic individuals relative to the lean normal controls. 2) The expression of p27Kip1 was also significantly decreased in genetically obese rodents relative to the lean normal controls. Additionally, in obese rodents, the concentrations of glucose or insulin were significantly increased relative to the lean normal controls. 3) Using human cells cultured in vitro it was found that the increased concentrations of glucose or insulin decrease the expression of p27Kip1. Conclusions: These results suggest that higher concentrations of glucose or insulin increase the risk of various types of cancer in obesity or type 2 diabetes by decreasing the expression of p27Kip1.展开更多
In the present study, 89 porcine reproductive and respiratory syndrome virus(PRRSV) isolates in China during 2007 to 2012 were randomly selected from the GenBank genetic sequence database. Evolutionary characteristics...In the present study, 89 porcine reproductive and respiratory syndrome virus(PRRSV) isolates in China during 2007 to 2012 were randomly selected from the GenBank genetic sequence database. Evolutionary characteristics of these isolates were analyzed based on the sequences of non-struc-tural protein 2(Nsp2) and glycoprotein 5(GP5). The genetic variations of the isolates were also compared with six representative strains. The results showed that a high degree of genetic diversity exists among the PRRSV population in China. Highly pathogenic PRRSV isolates, with a discon-tinuous deletion of a 30 amino acid residue in the Nsp2 region, remained the most dominant virus throughout 2007–2012 in China. Owing to the extensive use of representative vaccine strains, natu-ral recombination events occurred between strains. Three isolates – HH08, DY, and YN-2011 – were more closely related to vaccine strains than the other isolates. Both YN-2011 and DY were the evolu-tionary products of recombination events between strains SP and CH-1R. The results of the present study provide useful information for the epidemiology of PRRSV as well as for vaccine development.展开更多
目的 探讨胃癌细胞中的乙醛脱氢酶2(ALDH2) m RNA发生可变剪接。方法 设计ALDH2基因特异性引物,用胃癌细胞(AGS、HGC-27、MKN45)、正常人胃黏膜上皮细胞GES-1和人外周全血白细胞提取RNA,进行逆转录聚合酶链反应(RT-PCR)扩增,然后对ALDH...目的 探讨胃癌细胞中的乙醛脱氢酶2(ALDH2) m RNA发生可变剪接。方法 设计ALDH2基因特异性引物,用胃癌细胞(AGS、HGC-27、MKN45)、正常人胃黏膜上皮细胞GES-1和人外周全血白细胞提取RNA,进行逆转录聚合酶链反应(RT-PCR)扩增,然后对ALDH2扩增产物进行测序分析;使用DNAStar软件分析ALDH2变异体(V)的开放阅读框(ORF)。结果 ALDH2变异体1(V1)外显子2和外显子4发生可变剪接,V1外显子1的3’端和外显子3的5’端3个不同的位点发生可变剪接,V1存在8个长度超过100氨基酸的ORF。结论 ALDH2 m RNA存在多种可变剪接形式,提示其存在复杂的蛋白表达功能。展开更多
AIM: To isolate a novel isoform of human HPO (HPO-205) from human fetal liver Marathon-ready cDNA and characterize its primary biological function. METHODS: 5'-RACE (rapid amplification of cDNA 5' ends) was us...AIM: To isolate a novel isoform of human HPO (HPO-205) from human fetal liver Marathon-ready cDNA and characterize its primary biological function. METHODS: 5'-RACE (rapid amplification of cDNA 5' ends) was used to isolate a novel isoform of hHPO in this paper. The constructed pcDNA(HPO-205), pcDNA(HPO) and pcDNA eukaryotic expression vectors were respectively transfected by lipofectamine method and the stimulation of DNA synthesis was observed by (3)H-TdR incorporation assay. Proteins extracted from different cells were analyzed by Western blot. RESULTS: A novel isoform of hHPO (HPO-205) encoding a 205 amino acid ORF corresponding to a translated production of 23 kDa was isolated and distinguished from the previous HPO that lacked the N-terminal 80 amino acids. The dose-dependent stimulation of DNA synthesis of HepG2 hepatoma cells by HPO-205 demonstrated its similar biological activity with HPO in vitro. The level of MAPK (Mitogen-activated protein kinase) phosphorylation by Western blot analysis revealed that HPO-205 might have the stronger activity of stimulating hepatic cell proliferation than that of HPO. CONCLUSION: A novel isoform of hHPO (HPO-205) was isolated from hepatic-derived cells. The comparison of HPO-205 and HPO will lead to a new insight into the structure and function of hHPO, and provide the new way of thinking to deeply elucidate the biological roles of HPO/ALR.展开更多
The outbreak of coronavirus disease 2019(COVID-19)in Wuhan,China,was caused by a novel coronavirus(CoV),named severe acute respiratory syndrome coronavirus 2(SARS-CoV-2).The rapid detection of viral nucleic acids is c...The outbreak of coronavirus disease 2019(COVID-19)in Wuhan,China,was caused by a novel coronavirus(CoV),named severe acute respiratory syndrome coronavirus 2(SARS-CoV-2).The rapid detection of viral nucleic acids is critical for the early identification of infected cases.We have developed two TaqMan real-time reverse transcription-PCR assays to detect SARS-CoV-2.The designed primers target the nucleocapsid(N)and open reading frame(ORF)1b gene regions,where the probes discriminate SARS-CoV-2 from other human and animal CoVs.The sensitivities are one genomic copy per reaction for theN gene assay and ten copies for the ORF 1b gene assay.The overall linear detection ranges are 1–10^(6)and 10–10^(6)copies per reaction for the N gene assay and the ORF 1b gene assay,respectively.Surveillance of 23 suspected COVID-19 patients demonstrated that SARS-CoV-2 could be detected from 100%(23/23)and 62.5%(16/23)of clinical specimens by the N gene assay and the ORF 1b gene assay,respectively.All of the samples not detected by the ORF 1b gene assay were throat swabs,indicating a lower viral load in the upper respiratory tract and the relatively lower sensitivity of the ORF 1b gene assay.The assays developed in the present study offer alternative diagnostic tests for COVID-19.展开更多
文摘Research Aims: Obesity and type 2 diabetes are known to be associated with increased risk of various types of cancer. However, the molecular biological mechanism of how the risk of cancer is increased in obesity or type 2 diabetes is not known. The aim this research is to investigate if the decreased expression of p27Kip1, a cell cycle repressor protein, plays a central role in this mechanism. Research Methods, Previous Studies and Theoretical Backgrounds: It is well known that the expression of p27Kip1 is increased by numerous nutritional or chemopreventive anti-cancer agents. But it has never been known that the expression of p27Kip1 could be decreased, rather than increased, and the risk of cancer could be increased, rather than decreased. This problem was solved recently and this new analytical method was used in this study. Results: 1) The expression of p27Kip1 was indeed significantly decreased in human obese type 2 diabetic individuals relative to the lean normal controls. 2) The expression of p27Kip1 was also significantly decreased in genetically obese rodents relative to the lean normal controls. Additionally, in obese rodents, the concentrations of glucose or insulin were significantly increased relative to the lean normal controls. 3) Using human cells cultured in vitro it was found that the increased concentrations of glucose or insulin decrease the expression of p27Kip1. Conclusions: These results suggest that higher concentrations of glucose or insulin increase the risk of various types of cancer in obesity or type 2 diabetes by decreasing the expression of p27Kip1.
基金supported by the Jilin Province Science and Technology Development Project(No.20140101123JC)the Fundamental Research Fund of Jilin Universitythe Program for Changjiang Scholars and Innovative Research Team in University(No.IRT1248)
文摘In the present study, 89 porcine reproductive and respiratory syndrome virus(PRRSV) isolates in China during 2007 to 2012 were randomly selected from the GenBank genetic sequence database. Evolutionary characteristics of these isolates were analyzed based on the sequences of non-struc-tural protein 2(Nsp2) and glycoprotein 5(GP5). The genetic variations of the isolates were also compared with six representative strains. The results showed that a high degree of genetic diversity exists among the PRRSV population in China. Highly pathogenic PRRSV isolates, with a discon-tinuous deletion of a 30 amino acid residue in the Nsp2 region, remained the most dominant virus throughout 2007–2012 in China. Owing to the extensive use of representative vaccine strains, natu-ral recombination events occurred between strains. Three isolates – HH08, DY, and YN-2011 – were more closely related to vaccine strains than the other isolates. Both YN-2011 and DY were the evolu-tionary products of recombination events between strains SP and CH-1R. The results of the present study provide useful information for the epidemiology of PRRSV as well as for vaccine development.
文摘目的 探讨胃癌细胞中的乙醛脱氢酶2(ALDH2) m RNA发生可变剪接。方法 设计ALDH2基因特异性引物,用胃癌细胞(AGS、HGC-27、MKN45)、正常人胃黏膜上皮细胞GES-1和人外周全血白细胞提取RNA,进行逆转录聚合酶链反应(RT-PCR)扩增,然后对ALDH2扩增产物进行测序分析;使用DNAStar软件分析ALDH2变异体(V)的开放阅读框(ORF)。结果 ALDH2变异体1(V1)外显子2和外显子4发生可变剪接,V1外显子1的3’端和外显子3的5’端3个不同的位点发生可变剪接,V1存在8个长度超过100氨基酸的ORF。结论 ALDH2 m RNA存在多种可变剪接形式,提示其存在复杂的蛋白表达功能。
基金the National Natural Science Foundation of China,No.39830440
文摘AIM: To isolate a novel isoform of human HPO (HPO-205) from human fetal liver Marathon-ready cDNA and characterize its primary biological function. METHODS: 5'-RACE (rapid amplification of cDNA 5' ends) was used to isolate a novel isoform of hHPO in this paper. The constructed pcDNA(HPO-205), pcDNA(HPO) and pcDNA eukaryotic expression vectors were respectively transfected by lipofectamine method and the stimulation of DNA synthesis was observed by (3)H-TdR incorporation assay. Proteins extracted from different cells were analyzed by Western blot. RESULTS: A novel isoform of hHPO (HPO-205) encoding a 205 amino acid ORF corresponding to a translated production of 23 kDa was isolated and distinguished from the previous HPO that lacked the N-terminal 80 amino acids. The dose-dependent stimulation of DNA synthesis of HepG2 hepatoma cells by HPO-205 demonstrated its similar biological activity with HPO in vitro. The level of MAPK (Mitogen-activated protein kinase) phosphorylation by Western blot analysis revealed that HPO-205 might have the stronger activity of stimulating hepatic cell proliferation than that of HPO. CONCLUSION: A novel isoform of hHPO (HPO-205) was isolated from hepatic-derived cells. The comparison of HPO-205 and HPO will lead to a new insight into the structure and function of hHPO, and provide the new way of thinking to deeply elucidate the biological roles of HPO/ALR.
基金funded in part by the Project from the Ministry of Science and Technology in China(2020YFC0841200)the National Major Science&Technology Project for Control and Prevention of Major Infectious Diseases in China(2017ZX10103004)+2 种基金the Chinese Academy of Medical Sciences(CAMS)Innovation Fund for Medical Sciences(2020HY320001)the non-profit Central Research Institute Fund of Chinese Academy of Medical Sciences(2019PT310029)the Chinese Academy of Medical Sciences(CAMS)Innovation Fund for Medical Sciences(2016-I2M-1-014).
文摘The outbreak of coronavirus disease 2019(COVID-19)in Wuhan,China,was caused by a novel coronavirus(CoV),named severe acute respiratory syndrome coronavirus 2(SARS-CoV-2).The rapid detection of viral nucleic acids is critical for the early identification of infected cases.We have developed two TaqMan real-time reverse transcription-PCR assays to detect SARS-CoV-2.The designed primers target the nucleocapsid(N)and open reading frame(ORF)1b gene regions,where the probes discriminate SARS-CoV-2 from other human and animal CoVs.The sensitivities are one genomic copy per reaction for theN gene assay and ten copies for the ORF 1b gene assay.The overall linear detection ranges are 1–10^(6)and 10–10^(6)copies per reaction for the N gene assay and the ORF 1b gene assay,respectively.Surveillance of 23 suspected COVID-19 patients demonstrated that SARS-CoV-2 could be detected from 100%(23/23)and 62.5%(16/23)of clinical specimens by the N gene assay and the ORF 1b gene assay,respectively.All of the samples not detected by the ORF 1b gene assay were throat swabs,indicating a lower viral load in the upper respiratory tract and the relatively lower sensitivity of the ORF 1b gene assay.The assays developed in the present study offer alternative diagnostic tests for COVID-19.