【目的】建立基于鸡毒支原体种特异性粘附蛋白编码基因pvpA的实时荧光定量PCR检测方法。【方法】根据GenBank公布的不同国家和地区鸡毒支原体pvpA基因序列,在高度保守区域设计一对引物。以临床分离鸡毒支原体RC1为模板扩增pvpA基因,将...【目的】建立基于鸡毒支原体种特异性粘附蛋白编码基因pvpA的实时荧光定量PCR检测方法。【方法】根据GenBank公布的不同国家和地区鸡毒支原体pvpA基因序列,在高度保守区域设计一对引物。以临床分离鸡毒支原体RC1为模板扩增pvpA基因,将其连接到PMD19-T载体,转化至大肠杆菌DH5α中,经PCR和酶切鉴定并测序验证后得到阳性重组质粒rPvpA90。以rPvpA90为模板建立SYBR Green I荧光定量的标准曲线和溶点曲线,并进行特异性,灵敏性,重复性及临床样本检测试验,评价该方法的可行性。【结果】所建立的荧光定量PCR标准曲线循环阈值与模板浓度呈良好的线性关系,溶点曲线特异,相关系数为0.990。最低检测限为72拷贝/20μL,其敏感性比常规PCR至少高100倍;无论是对不同病原DNA单模板还是几种病原DNA混合模板进行扩增,该方法都呈现很好的特异性;重复性试验中,批内和批间变异系数均小于2%,表明该方法重现性好;临床样本的检测结果表明所建立的荧光定量PCR检测方法的检测率明显高于常规PCR方法。【结论】本研究初步建立了基于种特异性基因pvpA的鸡毒支原体荧光定量PCR方法,为养禽场诊断和监测鸡毒支原体病原提供一种新的特异、灵敏的方法。展开更多
BACKGROUND: Death-associated protein kinase (DAPK) is a Ca2+/calmodulin-regulated Ser/Thr kinase which is involved in apoptosis. The aberrant methylation of its promoter region CpG islands may be one of the important ...BACKGROUND: Death-associated protein kinase (DAPK) is a Ca2+/calmodulin-regulated Ser/Thr kinase which is involved in apoptosis. The aberrant methylation of its promoter region CpG islands may be one of the important mechanisms of carcinogenesis. We studied the relationship of methylation status and expression of the DAPK gene with the clinical findings in cholangiocarcinoma. METHODS: Target DNA was modified by sodium bisulfite, coverting all unmethylated, but not methylated, cytosines to uracil, and subsequently detected by methylation-specific PCR. Moreover, mRNA expression of the DAPK gene was assessed by RT-PCR. RESULTS: Aberrant methylation of the DAPK gene was detected in 11 (30.6%) of 36 tissue specimens of cholangiocarcinoma, and in 2 (5.6%) of 36 specimens of adjacent normal tissues. DAPK mRNA was not expressed in tumor and adjacent tissues with hypermethylation of the DAPK promoter. There were no statistical differences in the extent of differentiation and invasion, lymph node metastasis or pathologic type between the methylated and unmethylated tissues. CONCLUSIONS: The frequency of DAPK gene methylation in cholangiocarcinoma is high and it may offer an effective means for earlier auxiliary diagnosis of the malignancy. The DAPK gene is probably suppressed by methylation, and it could become resistant to apoptosis and immunological surveillance. The DAPK gene epigenetically affected by methylation may be associated with the carcinogenesis of cholangiocarcinoma.展开更多
To develop a gene therapy strategy for treating bovine mastitis, a new mammary-specific vector containing human lysozyme (hLYZ) cDNA and kanamycin resistance gene was constructed for intramammary expression and clinic...To develop a gene therapy strategy for treating bovine mastitis, a new mammary-specific vector containing human lysozyme (hLYZ) cDNA and kanamycin resistance gene was constructed for intramammary expression and clinical studies. After one time acupuncture or intracisternal infusion of healthy cows with 400 μg of the p215C3LYZ vector, over 2.0 μg/ml of rhLYZ could be detected by enzymatic assay for about 3 weeks in the milk samples. Western blotting showed that rhLYZ secreted into milk samples from the vector-injected cows had molecular weight similar to that of the natural hLYZ in human colostrums. Twenty days after the primary injection, the quarters were re-injected with the same vector by quarter acupuncture and even higher concentrations of rhLYZ could be detected. Indirect competitive ELISA of milk samples showed that the vector injection did not induce detectable humoral immune response against hLYZ. Clinical studies showed that twice acupuncture of quarters with the p215C3LYZ vector had overt therapeutic effect on clinical and subclinical mastitis previously treated with antibiotics, including disappearance of clinical symptoms and relatively high microbiological cure rates. These data provide a solid rationale for using the vector to develop gene therapy for treating bovine mastitis.展开更多
BACKGROUND Liver cancer has a high mortality and morbidity rate throughout the world.In clinical practice,the prognosis of liver cancer patients is poor,and the complex reasons contribute to treatment failures,includi...BACKGROUND Liver cancer has a high mortality and morbidity rate throughout the world.In clinical practice,the prognosis of liver cancer patients is poor,and the complex reasons contribute to treatment failures,including fibrosis,hepatitis viral infection,drug resistance and metastasis.Thus,screening novel prognostic biomarkers is of great importance for guiding liver cancer therapy.Orosomucoid genes(ORMs)encode acute phase plasma proteins,including orosomucoid 1(ORM1)and ORM2.Previous studies showed their upregulation upon inflammation,but the specific function of ORMs has not yet been determined,especially in the development of liver cancer.AIM To determine the expression of ORMs and their potential function in liver cancer.METHODS Analysis of the expression of ORMs in different human tissues was performed on data from the HPA RNA-seq normal tissues project.The expression ratio of ORMs was determined using the HCCDB database,including the ratio between liver cancer and other cancers,normal liver and other normal tissues,liver cancer and adjacent normal liver tissues.Analysis of ORM expression in different cancer types was performed using The Cancer Genome Atlas and TIMER database.The expression of ORMs in liver tumor tissues and adjacent normal tissues were further confirmed using Gene Expression Omnibus data,including GSE36376 and GSE14520.The 10-year overall survival(OS),progression-free survival(PFS)and relapse-free survival(RFS)rates between high and low ORM expression groups in liver cancer patients were determined using the Kaplan-Meier plotter tool.Gene Set Enrichment Analysis(GSEA)was employed to explore the ORM2-associated signaling network.Correlations between ORM2 expression and tumor purity or the infiltration level of macrophages in liver tumor tissues were determined using the TIMER database.The correlation between ORM2 gene levels,tumor-associated macrophage(TAM)markers(including CD68 and TGFβ1)and T cell immunosuppression(including CTLA4 and PD-1)in liver tumor tissues and liver GTEx was determi展开更多
为了研究10种芽孢杆菌的基本特性,下载到70条芽孢杆菌属细菌的16S r RNA序列,通过对比芽孢杆菌的基本特征和16S r RNA序列种内和种间相似性,发现基本特征很难区分这10种菌株。16S r RNA序列种内相似性最高为100%,最低的是B.amyloliquefa...为了研究10种芽孢杆菌的基本特性,下载到70条芽孢杆菌属细菌的16S r RNA序列,通过对比芽孢杆菌的基本特征和16S r RNA序列种内和种间相似性,发现基本特征很难区分这10种菌株。16S r RNA序列种内相似性最高为100%,最低的是B.amyloliquefaciens,种内分化较明显,最低值为90.85%,种间相似性最高的2个菌株是B.subtilis strain 168和B.amyloliquefaciens strain BCRC 11601,最高值为99.66%,最低为92.01%。B.subtilis、B.amyloliquefaciens、B.anthracis、B.cereus、B.methylotrophicus、B.atrophaeus之间某些菌株的16S r RNA相似性极高,通过16S r RNA序列很难区分,B.coagulans的16S r RNA特异性最好。同时本研究提供了gyr A、gyr B、rpo A、yya R、yya O等多个能够准确鉴定的特异性基因,为快速鉴定菌种提供了便利。展开更多
Hepatocellular carcinoma (HCC) is one of the most common cancers in Eastern Asia, and its incidence is increasing globally. Numerous experimental models have been developed to better our understanding of the pathogeni...Hepatocellular carcinoma (HCC) is one of the most common cancers in Eastern Asia, and its incidence is increasing globally. Numerous experimental models have been developed to better our understanding of the pathogenic mechanism of HCC and to evaluate novel therapeutic approaches. Molecular imaging is a convenient and up-to-date biomedical tool that enables the visualization, characterization and quantification of biologic processes in a living subject. Molecular imaging based on reporter gene expression, in particular, can elucidate tumor-specific events or processes by acquiring images of a reporter gene’s expression driven by tumor-specific enhancers/promoters. In this review, we discuss the advantages and disadvantages of various experimental HCC mouse models and we present in vivo images of tumor-specific reporter gene expression driven by an alpha-fetoprotein (AFP) enhancer/promoter system in a mouse model of HCC. The current mouse models of HCC development are established by xenograft, carcinogen induction and genetic engineering, representing the spectrum of tumor-inducing factors and tumor locations. The imaging analysis approach of reporter genes driven by AFP enhancer/promoter is presented for these different HCC mouse models. Such molecular imaging can provide longitudinal information about carcinogenesis and tumor progression. We expect that clinical application of AFP-targeted reporter gene expression imaging systems will be useful for the detection of AFP-expressing HCC tumors and screening of increased/decreased AFP levels due to disease or drug treatment.展开更多
To solve the problem of embryonic lethality in conventional gene knockouts, site-specific recombinase （SSR） systems （Cre-loxP, FIp-FRT, and φC31） have been used for tissue-specific gene knockout. With the combina...To solve the problem of embryonic lethality in conventional gene knockouts, site-specific recombinase （SSR） systems （Cre-loxP, FIp-FRT, and φC31） have been used for tissue-specific gene knockout. With the combination of an SSR system and inducible gene expression systems （tetracycline and tamoxifen）, stage-specific knockout and transgenic expression can be achieved. The application of this ＂SSR＋inducible＂ conditional tool to genomic manipulation can be extended in various ways. Alternatives to conditional gene targeting, such as conditional gene trapping, multipurpose conditional alleles, and conditional gene silencing, have been developed. SSR systems can also be used to construct precise disease models with point mutations and chromosomal abnormalities. With these exciting achievements, we are moving towards a new era in which the whole genome can be manipulated as we wish.展开更多
文摘【目的】建立基于鸡毒支原体种特异性粘附蛋白编码基因pvpA的实时荧光定量PCR检测方法。【方法】根据GenBank公布的不同国家和地区鸡毒支原体pvpA基因序列,在高度保守区域设计一对引物。以临床分离鸡毒支原体RC1为模板扩增pvpA基因,将其连接到PMD19-T载体,转化至大肠杆菌DH5α中,经PCR和酶切鉴定并测序验证后得到阳性重组质粒rPvpA90。以rPvpA90为模板建立SYBR Green I荧光定量的标准曲线和溶点曲线,并进行特异性,灵敏性,重复性及临床样本检测试验,评价该方法的可行性。【结果】所建立的荧光定量PCR标准曲线循环阈值与模板浓度呈良好的线性关系,溶点曲线特异,相关系数为0.990。最低检测限为72拷贝/20μL,其敏感性比常规PCR至少高100倍;无论是对不同病原DNA单模板还是几种病原DNA混合模板进行扩增,该方法都呈现很好的特异性;重复性试验中,批内和批间变异系数均小于2%,表明该方法重现性好;临床样本的检测结果表明所建立的荧光定量PCR检测方法的检测率明显高于常规PCR方法。【结论】本研究初步建立了基于种特异性基因pvpA的鸡毒支原体荧光定量PCR方法,为养禽场诊断和监测鸡毒支原体病原提供一种新的特异、灵敏的方法。
基金The study was supported by a grant from the Provincial Outstanding Youth Foundation of Shandong, China (No. 2005BS02008).
文摘BACKGROUND: Death-associated protein kinase (DAPK) is a Ca2+/calmodulin-regulated Ser/Thr kinase which is involved in apoptosis. The aberrant methylation of its promoter region CpG islands may be one of the important mechanisms of carcinogenesis. We studied the relationship of methylation status and expression of the DAPK gene with the clinical findings in cholangiocarcinoma. METHODS: Target DNA was modified by sodium bisulfite, coverting all unmethylated, but not methylated, cytosines to uracil, and subsequently detected by methylation-specific PCR. Moreover, mRNA expression of the DAPK gene was assessed by RT-PCR. RESULTS: Aberrant methylation of the DAPK gene was detected in 11 (30.6%) of 36 tissue specimens of cholangiocarcinoma, and in 2 (5.6%) of 36 specimens of adjacent normal tissues. DAPK mRNA was not expressed in tumor and adjacent tissues with hypermethylation of the DAPK promoter. There were no statistical differences in the extent of differentiation and invasion, lymph node metastasis or pathologic type between the methylated and unmethylated tissues. CONCLUSIONS: The frequency of DAPK gene methylation in cholangiocarcinoma is high and it may offer an effective means for earlier auxiliary diagnosis of the malignancy. The DAPK gene is probably suppressed by methylation, and it could become resistant to apoptosis and immunological surveillance. The DAPK gene epigenetically affected by methylation may be associated with the carcinogenesis of cholangiocarcinoma.
基金Project (Nos. BJ2001315 and BE2004611) supported by the De-partment of Science and Technology of Jiangsu Province, China
文摘To develop a gene therapy strategy for treating bovine mastitis, a new mammary-specific vector containing human lysozyme (hLYZ) cDNA and kanamycin resistance gene was constructed for intramammary expression and clinical studies. After one time acupuncture or intracisternal infusion of healthy cows with 400 μg of the p215C3LYZ vector, over 2.0 μg/ml of rhLYZ could be detected by enzymatic assay for about 3 weeks in the milk samples. Western blotting showed that rhLYZ secreted into milk samples from the vector-injected cows had molecular weight similar to that of the natural hLYZ in human colostrums. Twenty days after the primary injection, the quarters were re-injected with the same vector by quarter acupuncture and even higher concentrations of rhLYZ could be detected. Indirect competitive ELISA of milk samples showed that the vector injection did not induce detectable humoral immune response against hLYZ. Clinical studies showed that twice acupuncture of quarters with the p215C3LYZ vector had overt therapeutic effect on clinical and subclinical mastitis previously treated with antibiotics, including disappearance of clinical symptoms and relatively high microbiological cure rates. These data provide a solid rationale for using the vector to develop gene therapy for treating bovine mastitis.
基金Supported by Medicine and Health Science and Technology Plan Projects of Zhejiang Province,No.2018KY569Zhejiang Provincial Natural Science Foundation of China,No.LY17H030002
文摘BACKGROUND Liver cancer has a high mortality and morbidity rate throughout the world.In clinical practice,the prognosis of liver cancer patients is poor,and the complex reasons contribute to treatment failures,including fibrosis,hepatitis viral infection,drug resistance and metastasis.Thus,screening novel prognostic biomarkers is of great importance for guiding liver cancer therapy.Orosomucoid genes(ORMs)encode acute phase plasma proteins,including orosomucoid 1(ORM1)and ORM2.Previous studies showed their upregulation upon inflammation,but the specific function of ORMs has not yet been determined,especially in the development of liver cancer.AIM To determine the expression of ORMs and their potential function in liver cancer.METHODS Analysis of the expression of ORMs in different human tissues was performed on data from the HPA RNA-seq normal tissues project.The expression ratio of ORMs was determined using the HCCDB database,including the ratio between liver cancer and other cancers,normal liver and other normal tissues,liver cancer and adjacent normal liver tissues.Analysis of ORM expression in different cancer types was performed using The Cancer Genome Atlas and TIMER database.The expression of ORMs in liver tumor tissues and adjacent normal tissues were further confirmed using Gene Expression Omnibus data,including GSE36376 and GSE14520.The 10-year overall survival(OS),progression-free survival(PFS)and relapse-free survival(RFS)rates between high and low ORM expression groups in liver cancer patients were determined using the Kaplan-Meier plotter tool.Gene Set Enrichment Analysis(GSEA)was employed to explore the ORM2-associated signaling network.Correlations between ORM2 expression and tumor purity or the infiltration level of macrophages in liver tumor tissues were determined using the TIMER database.The correlation between ORM2 gene levels,tumor-associated macrophage(TAM)markers(including CD68 and TGFβ1)and T cell immunosuppression(including CTLA4 and PD-1)in liver tumor tissues and liver GTEx was determi
文摘为了研究10种芽孢杆菌的基本特性,下载到70条芽孢杆菌属细菌的16S r RNA序列,通过对比芽孢杆菌的基本特征和16S r RNA序列种内和种间相似性,发现基本特征很难区分这10种菌株。16S r RNA序列种内相似性最高为100%,最低的是B.amyloliquefaciens,种内分化较明显,最低值为90.85%,种间相似性最高的2个菌株是B.subtilis strain 168和B.amyloliquefaciens strain BCRC 11601,最高值为99.66%,最低为92.01%。B.subtilis、B.amyloliquefaciens、B.anthracis、B.cereus、B.methylotrophicus、B.atrophaeus之间某些菌株的16S r RNA相似性极高,通过16S r RNA序列很难区分,B.coagulans的16S r RNA特异性最好。同时本研究提供了gyr A、gyr B、rpo A、yya R、yya O等多个能够准确鉴定的特异性基因,为快速鉴定菌种提供了便利。
基金Supported by Korea Science and Engineering Foundation,No.2012M2A2A7013480 and No.2013M2C2A1074238
文摘Hepatocellular carcinoma (HCC) is one of the most common cancers in Eastern Asia, and its incidence is increasing globally. Numerous experimental models have been developed to better our understanding of the pathogenic mechanism of HCC and to evaluate novel therapeutic approaches. Molecular imaging is a convenient and up-to-date biomedical tool that enables the visualization, characterization and quantification of biologic processes in a living subject. Molecular imaging based on reporter gene expression, in particular, can elucidate tumor-specific events or processes by acquiring images of a reporter gene’s expression driven by tumor-specific enhancers/promoters. In this review, we discuss the advantages and disadvantages of various experimental HCC mouse models and we present in vivo images of tumor-specific reporter gene expression driven by an alpha-fetoprotein (AFP) enhancer/promoter system in a mouse model of HCC. The current mouse models of HCC development are established by xenograft, carcinogen induction and genetic engineering, representing the spectrum of tumor-inducing factors and tumor locations. The imaging analysis approach of reporter genes driven by AFP enhancer/promoter is presented for these different HCC mouse models. Such molecular imaging can provide longitudinal information about carcinogenesis and tumor progression. We expect that clinical application of AFP-targeted reporter gene expression imaging systems will be useful for the detection of AFP-expressing HCC tumors and screening of increased/decreased AFP levels due to disease or drug treatment.
基金Project supported by the National Natural Science Foundation of China(Nos.30871436,30973297,and 31171194)the National Basic Research Program(973)of China(No.2010CB945002)+1 种基金the Ministry of Education of China(No.200804220011)Shandong Provincial Science and Technology Key Program(No.2009GG10003039),China
文摘To solve the problem of embryonic lethality in conventional gene knockouts, site-specific recombinase （SSR） systems （Cre-loxP, FIp-FRT, and φC31） have been used for tissue-specific gene knockout. With the combination of an SSR system and inducible gene expression systems （tetracycline and tamoxifen）, stage-specific knockout and transgenic expression can be achieved. The application of this ＂SSR＋inducible＂ conditional tool to genomic manipulation can be extended in various ways. Alternatives to conditional gene targeting, such as conditional gene trapping, multipurpose conditional alleles, and conditional gene silencing, have been developed. SSR systems can also be used to construct precise disease models with point mutations and chromosomal abnormalities. With these exciting achievements, we are moving towards a new era in which the whole genome can be manipulated as we wish.
