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Testicular expression of survivin and human telomerase reverse transcriptase(hTERT)associated with spermatogenic function in infertile patients 被引量:8
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作者 Steffen Weikert Frank Christoph +5 位作者 Wolfgang Schulze Hans Krause Carsten Kempkensteffen Martin Schostak Kurt Miller Mark Schrader 《Asian Journal of Andrology》 SCIE CAS CSCD 2006年第1期95-100,共6页
Aim: To characterize the coexpression of survivin, an inhibitor of apoptosis (IAF), and human telomerase reverse transcriptase (hTERT) in human testes with varying spermatogenic function. Methods: Transcript lev... Aim: To characterize the coexpression of survivin, an inhibitor of apoptosis (IAF), and human telomerase reverse transcriptase (hTERT) in human testes with varying spermatogenic function. Methods: Transcript levels of survivin mRNA and hTERT mRNA were determined in normal testes (n = 11) and testes with defective spermatogenesis (n = 28) using real-time reverse-transcription polymerase chain reaction (RT-PCR). The histological work-up was performed according to a modified Johnsen score. Results: Expressions of both survivin and hTERT were highest at median levels of 96.8 and 709 in normal spermatogenesis and dropped to 53.3 and 534 in testes with postmeiotic spermatogenic arrest (n = 10). In severe spermatogenic failure (n = 18), survivin expression was lacking in most specimens (n = 16), whereas at least low levels of testicular hTERT expression were largely detectable with a normalized expression of 73 in premeiotic spermatogenic arrest (n = 7) and 45 in patients with Sertoli cell-only syndrome (SCOS) (n = 3). Both survivin and hTERT expressions increased with a progressing Johnsen score (P for trend = 0.001). Conclusion: Although both survivin and hTERT are correlated with spermatogenic function, they show different expression patterns in testes of infertile patients. These findings substantiate results from studies in the rodent testis suggesting a predominant expression of survivin in meiotically dividing germ cells. (Asian J Andro12006 Jan; 8: 95-100) 展开更多
关键词 SURVIVIN human telomerase reverse transcriptase apoptosis AZOOSPERMIA male infertility SPERMATOGENESIS
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Neuroprotective effects of human telomerase reverse transcriptase on beta-amyloid fragment 25-35-treated human embryonic cortical neurons 被引量:3
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作者 Lingping Kong Lingzhi Wu +2 位作者 Jie Zhang Yaping Liao Huaqiao Wang 《Neural Regeneration Research》 SCIE CAS CSCD 2009年第6期405-412,共8页
BACKGROUND: Numerous current studies have suggested that human telomerase reverse transcriptase (hTERT) gene has neuroprotective effects and can inhibit apoptosis induced by various cytotoxic stresses; however, the... BACKGROUND: Numerous current studies have suggested that human telomerase reverse transcriptase (hTERT) gene has neuroprotective effects and can inhibit apoptosis induced by various cytotoxic stresses; however, the mechanism of action remains unknown. OBJECTIVE: To evaluate the neuroprotective effects and possible mechanism of action of hTERT gene transfection in human embryonic cortical neurons treated with beta-amyloid fragment 25-35 (AI325-35). DESIGN, TIME AND SETTING: The randomized, controlled and molecular biological studies were performed at the Department of Anatomy and Brain Research, Zhongshan School of Medicine, Sun Yat-sen University, China, from September 2005 to June 2008. MATERIALS: AdEasy-1 Expression System was gifted by Professor Guoquan Gao from Sun Yat-Sen University, China. Human cortical neurons were derived from 12-20 week old aborted fetuses, obtained from the Guangzhou Maternal and Child Health Hospital, China. Mouse anti-Odk5 and mouse anti-p16 monoclonal antibodies (Lab Vision, USA), and mouse anti-hTERT monoclonal antibody (Epitomics, USA), were used in this study. METHODS: (1) Recombinant adenovirus vectors, encoding hTERT (Ad-hTERT) and green fluorescent protein (Ad-GFP), were constructed using the AdEasy-1 Expression System. Human embryonic cortical neurons in the Ad-hTERT group were transfected with Ad-hTERT for 1-21 days. Likewise, human embryonic cortical neurons in the Ad-GFP group were transfected with Ad-GFP for 1-21 days. Human embryonic cortical neurons in the control group were cultured as normal. (2) Human embryonic cortical neurons in the Ad-hTERT group were treated with 10 pmol/L Aβ25-35 for 24 hours. Normal human embryonic cortical neurons treated with 10 pmol/Lβ25.35 for 24 hours served as a model group. Human embryonic cortical neurons in the Ad-GFP and control groups were not treated with Aβ25-35. MAIN OUTCOME MEASURES: Expression of hTERT in human embryonic cortical neurons was evaluated by immunocytochemical staining and Western blot assay. Telomerase activity was measured using a PCR-based telomeric repeat amplification protocol (TRAP) ELISA kit. Neural activity in human embryonic cortical neurons was examined by MTT assay; apoptosis was measured using TUNEL assay; and Cdk5 and p16 protein expressions were measured by Western blot. RESULTS: Expression of hTERT protein was significantly increased and peaked at day 3 post-transfection in the Ad-hTERT group. No hTERT expression was detected in the Ad-GFP and control groups. Telomerase activity was significantly greater in the Ad-hTERT group compared with the Ad-GFP and control groups (P 〈 0.01). Compared with the control group, cell activity was significantly decreased (P 〈 0.05), and cell apoptotic rate, Cdk5 and p16 expression were significantly increased (P 〈 0.01) in the model group. Compared with the model group, cell activity was increased in the Ad-hTERT group, and peaked at day 3 post-transfection (P 〈 0.05). Neuroprotective effects also peaked at day 3 post-transfection; and the apoptotic rate, Cdk5 and p16 expression significantly decreased (P 〈 0.01). CONCLUSION: Expression of hTERT in human embryonic cortical neurons can relieve Aβ25-35-induced neuronal apoptosis. The possible mechanism by which hTERT produces these neuroprotective effects may be associated with inhibition of Cdk5 and p16 expression. 展开更多
关键词 human telomerase reverse transcriptase cortical neuron human embryo Alzheimer's disease beta-amyloid fragment 25-35 CDK5 P16
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Quantification of human telomerase RNA(hTR)and human telomerase reverse transcriptase(hTERT)mRNA in testicular tissue of infertile patients 被引量:3
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作者 Mark Schrader Markus Müller +2 位作者 Rüdiger Heicappell Bernd Straub Kurt Miller 《Asian Journal of Andrology》 SCIE CAS CSCD 2001年第4期263-270,共8页
Aim:To evaluate the quantitative detection of human telomerase RNA(hTR)and human telomerase reverse tran-scriptase(hTERT)mRNA as diagnostic parameters in the workup of testicular tissue specimens from patients present... Aim:To evaluate the quantitative detection of human telomerase RNA(hTR)and human telomerase reverse tran-scriptase(hTERT)mRNA as diagnostic parameters in the workup of testicular tissue specimens from patients presentingwith non-obstructive azoospermia.Methods:hTR and hTERT mRNA expression were quantified in 38 cryopre-served testicular tissue specimens by fluorescence real-time reverse transcription-polymerase chain reaction(RT-PCR)in a LightCycler(r).This was paralleled by conventional histological workup in all tissue specimens and additionalsemithin sectioning preparation in cases with maturation arrest(n=12)and Sertoli-cell-only syndrome(n=12).Re-sults;The average normalized hTERT expression(N_(hTERT))was 131.9±48.0 copies(mean±SD)in tissue speci-mens with full spermatogenesis,N_(hTERT)=51.2±17.2 copies in those with maturation arrest and N_(hTERT)=2.7±2.4copies in those with Sertoli-cell-only syndrome(SCOS).The discriminant analysis showed that detection of N_(hTERT)(N_(hTR))had a predictive value of 86.8%(55.3%)for correct classification in one of the three histological subgroups.Conclusion;Our results demonstrate that quantitative detection of hTERT mRNA expression in testicular tissue en-ables a molecular-diagnostic classification of gametogenesis.Quantitative detection of hTERT in testicular biopsies isthus well suited for supplementing the histopathological evaluation. 展开更多
关键词 SPERMATOGENESIS human telomerase reverse transcriptase human telomerase RNA FErtILITY
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Trichostatin A Induces Apoptosis by Inhibiting Telomerase Activity and Expression of Telomerase Reverse Transcriptase in HL-60 Cells
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作者 周咏明 郭伟 +6 位作者 周浩 李慧玉 刘黎琼 姚军霞 郑金娥 郭天南 黄士昂 《Journal of Chinese Pharmaceutical Sciences》 CAS 2006年第2期115-120,共6页
Aim To investigate the effects of trichostatin A (TSA) on telomerase activity and the expression of human telomerase reverse transcriptase (hTERT) during apoptosis in vitro and the mechanisms in HL-60 cells. Metho... Aim To investigate the effects of trichostatin A (TSA) on telomerase activity and the expression of human telomerase reverse transcriptase (hTERT) during apoptosis in vitro and the mechanisms in HL-60 cells. Methods The proliferative activity of HL-60 cells was assessed by MTT assay. Cell apoptosis was analyzed by flow cytometry. Telomerase activity was examined by TRAP-ELISA. The expression of telomerase subunits was analyzed by RT-PCR. Results A time- and dose-dependent inhibition was detected in HL-60 cells treated with TSA. After treatment with 600 nmol· L^-1 TSA for 48 h, the apoptosis rate in HL-60 cells was 42. 6% and telomerase activity decreased 1.95 ± 0.25, 1.73 ± 0. 12, and 1.52 ± 0. 09 for 12, 24, and 48 h, respectively. The expression of hTERTmRNA decreased. No significant changes were observed in the expression of hTRmRNA and hTPI mRNA. Condusion TSA inhibits telomerase activity and induces apoptosis in HL-60 cells. The underlying mechanism may be related to the down-regulation of hTERT transcription. 展开更多
关键词 trichostatin A APOPTOSIS TELOMERASE human telomerase reverse transcriptase
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Naturally occurring hepatitis B virus reverse transcriptase mutations related to potential antiviral drug resistance and liver disease progression 被引量:17
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作者 Yu-Min Choi So-Young Lee Bum-Joon Kim 《World Journal of Gastroenterology》 SCIE CAS 2018年第16期1708-1724,共17页
The annual number of deaths caused by hepatitis B virus(HBV)-related disease, including cirrhosis and hepatocellular carcinoma(HCC), is estimated as 887000. The reported prevalence of HBV reverse transcriptase(RT) mut... The annual number of deaths caused by hepatitis B virus(HBV)-related disease, including cirrhosis and hepatocellular carcinoma(HCC), is estimated as 887000. The reported prevalence of HBV reverse transcriptase(RT) mutation prior to treatment is varied and the impact of preexisting mutations on the treatment of na?ve patients remains controversial, and primarily depends on geographic factors, HBV genotypes, HBe Ag serostatus, HBV viral loads, disease progression, intergenotypic recombination and co-infection with HIV. Different sensitivity of detection methodology used could also affect their prevalence results. Several genotype-dependent HBV RT positions that can affect the emergence of drug resistance have also been reported. Eight mutations in RT(rtL80I, rtD134N, rtN139K/T/H, rtY141F, rtM204I/V, rtF221Y, rtI224V, and rtM309K) are significantly associated with HCC progression. HBe Ag-negative status, low viral load, and genotype C infection are significantly related to a higher frequency and prevalence of preexisting RT mutations. Preexisting mutations are most frequently found in the A-B interdomain of RT which overlaps with the HBs Ag "a" determinant region, mutations of which can lead to simultaneous viral immune escape. In conclusion, the presence of baseline RT mutations can affect drug treatment outcomes and disease progression in HBVinfected populations via modulation of viral fitness and host-immune responses. 展开更多
关键词 POLYMERASE HEPATOCELLULAR carcinoma reverse transcriptase preexisting MUTATIONS HEPATITIS B virus
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Unique case of oligoastrocytoma with recurrence and grade progression:Exhibiting differential expression of high mobility group-A1 and human telomerase reverse transcriptase 被引量:3
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作者 Puneet Gandhi Richa Khare +3 位作者 Kavita Niraj Nitin Garg Sandeep K Sorte Hanni Gulwani 《World Journal of Clinical Cases》 SCIE 2016年第9期296-301,共6页
Mixed gliomas, primarily oligoastrocytomas, account for about 5%-10% of all gliomas. Distinguishing oligoastrocytoma based on histological features alone has limitations in predicting the exact biological behavior, ne... Mixed gliomas, primarily oligoastrocytomas, account for about 5%-10% of all gliomas. Distinguishing oligoastrocytoma based on histological features alone has limitations in predicting the exact biological behavior, necessitating ancillary markers for greater specificity. In this case report, human telomerase reverse transcriptase(hT ERT) and high mobility group-A1(HMGA1); markers of proliferation and stemness, have been quantitatively analyzed in formalin-fixed paraffin-embedded tissue samples of a 34 years old patient with oligoastrocytoma. Customized florescence-based immunohistochemistry protocol with enhanced sensitivity and specificity is used in the study. The patient presented with a history of generalized seizures and his magnetic resonance imaging scans revealed infiltrative ill-defined mass lesion with calcified foci within the left frontal white matter, suggestive of glioma. He was surgically treated at our center for four consecutive clinical events. Histopathologically, the tumor was identified as oligoastrocytoma-grade Ⅱ followed by two recurrence events and final progression to grade Ⅲ. Overall survival of the patient without adjuvant therapy was more than 9 years. Glial fibrillary acidic protein, p53, Ki-67, nuclear atypia index, pre-operative neutrophillymphocyte ratio, are the other parameters assessed. Findings suggest that hT ERT and HMGA1 are linked to tumor recurrence and progression. Established markers can assist in defining precise histopathological grade in conjuction with conventional markers in clinical setup. 展开更多
关键词 Human TELOMERASE reverse transcriptase High mobility group-A1 Oligoastrocytoma RECURRENCE Tumor GRADE
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Transplantation of human telomerase reverse transcriptase gene-transfected Schwann cells for repairing spinal cord injury 被引量:3
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作者 Shu-quan Zhang Min-fei Wu +3 位作者 Jia-bei Liu Ye Li Qing-san Zhu Rui Gu 《Neural Regeneration Research》 SCIE CAS CSCD 2015年第12期2040-2047,共8页
Transfection of the human telomerase reverse transcriptase(h TERT)gene has been shown to increase cell proliferation and enhance tissue repair.In the present study,h TERT was transfected into rat Schwann cells.A rat... Transfection of the human telomerase reverse transcriptase(h TERT)gene has been shown to increase cell proliferation and enhance tissue repair.In the present study,h TERT was transfected into rat Schwann cells.A rat model of acute spinal cord injury was established by the modified free-falling method.Retrovirus PLXSN was injected at the site of spinal cord injury as a vector to mediate h TERT gene-transfected Schwann cells(1×10^(10)/L;10μL)or Schwann cells(1×10^(10)/L;10μL)without h TERT gene transfection.Between 1 and 4 weeks after model establishment,motor function of the lower limb improved in the h TERT-transfected group compared with the group with non-transfected Schwann cells.Terminal deoxynucleotidyl transferase-mediated d UTP nick-end labeling and reverse transcription-polymerase chain reaction results revealed that the number of apoptotic cells,and gene expression of aquaporin 4/9 and matrix metalloproteinase 9/2decreased at the site of injury in both groups;however,the effect improved in the h TERT-transfected group compared with the Schwann cells without h TERT transfection group.Hematoxylin and eosin staining,PKH26 fluorescent labeling,and electrophysiological testing demonstrated that compared with the non-transfected group,spinal cord cavity and motor and sensory evoked potential latencies were reduced,while the number of PKH26-positive cells and the motor and sensory evoked potential amplitude increased at the site of injury in the h TERT-transfected group.These findings suggest that transplantation of h TERT gene-transfected Schwann cells repairs the structure and function of the injured spinal cord. 展开更多
关键词 nerve regeneration spinal cord injury Schwann cells TRANSPLANTATION motor function TELOMERASE reverse transcriptase PROLIFERATION MODIFICATION cells neural regeneration
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Inhibition of telomerase with human telomerase reverse transcriptase antisense increases the sensitivity of tumor necrosis factor-α-induced apoptosis in prostate cancer cells 被引量:3
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作者 Xiao-Dong Gao Yi-Rong Chen 《Asian Journal of Andrology》 SCIE CAS CSCD 2007年第5期697-704,共8页
Aim: To investigate the effect of inhibition of telomerase with human telomerase reverse transcriptase (hTERT) antisense on tumor necrosis factor-α (TNF-α-induced apoptosis in prostate cancer cells (PC3). Meth... Aim: To investigate the effect of inhibition of telomerase with human telomerase reverse transcriptase (hTERT) antisense on tumor necrosis factor-α (TNF-α-induced apoptosis in prostate cancer cells (PC3). Methods: Antisense phosphorothioate oligodeoxynucleotide (AS PS-ODN) was synthesized and purified. Telomerase activity was measured using the telomeric repeat amplification protocol (TRAP) and polymerase chain reaction enzyme-linked immunoassay (PCR-ELISA). hTERT mRNA was measured by reverse transcription PCR (RT-PCR) assay and gel-image system, hTERT protein was detected by immunochemistry and flow cytometry. Cell viability was detected by 3-(4, 5-dimethylthiazol-2-yl)-2,5-Diphenyltetrazolium (MTT) assay. Cell apoptosis was observed by morphological method and determined by flow cytometry. Results: The telomerase activity decreased with time after hTERT AS PS-ODN treatment. The levels of hTERT mRNA decreased with time after hTERT AS PS-ODN treatment, which appeared before the decline of the telomerase activity. The percentage of positive cells of hTERT protein declined with time after hTERT AS PS-ODN treatment, which appeared after the decline of hTERT mRNA. There was no difference in telomerase activity, hTERT mRNA and protein levels between hTERT sense phosphorothioate oligodeoxynucleotide (S PS-ODN) and the control group. The cell viability decreased with time after hTERT AS PS-ODN combined with TNF-α treatment. The percentage of apoptosis increased with time after hTERT AS PS-ODN combined with TNF-α treatment. There was no difference in cell viability and the percentage of apoptosis between hTERT S PS-ODN and the control group. Conclusion: hTERT AS PS-ODN can significantly inhibit telomerase activity by downregulating the hTERT mRNA and protein expression, and inhibition of telomerase with hTERT antisense can enhance TNF-α- induced apoptosis of PC3 cells. 展开更多
关键词 human telomerase reverse transcriptase antisense phosphorothioate oligodeoxynucleotide TELOMERASE prostate cancer cells tumor necrosis factor-α
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Structural Characteristics and Molecular Mechanism of Hepatitis B Virus Reverse Transcriptase 被引量:6
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作者 Hui FENG Kang-hong HU 《Virologica Sinica》 SCIE CAS CSCD 2009年第6期509-517,共9页
Hepatitis B virus (HBV), a typical member of the Hepadnaviridae family, is responsible for infections that cause B-type hepatitis which leads to severe public health problems around the world. The small enveloped DNA-... Hepatitis B virus (HBV), a typical member of the Hepadnaviridae family, is responsible for infections that cause B-type hepatitis which leads to severe public health problems around the world. The small enveloped DNA-containing virus replicates via reverse transcription, and this unique process is accomplished by the virally encoded reverse transcriptase (RT). This multi-functional protein plays a vital role in the viral life cycle. Here, we provide a summary of current knowledge regarding the structural characteristics and molecular mechanisms of HBV RT. Improved understanding of these processes is of both theoretical and practical significance for fundamental studies of HBV and drug discovery. 展开更多
关键词 HEPADNAVIRUS Hepatitis B virus (HBV) reverse transcriptase
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Telomerase Activity and Telomerase Reverse Transcriptase Expression Induced by Selenium in Rat Hepatocytes 被引量:2
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作者 RI-AN YU HUA-JIE CHEN +2 位作者 LING-FEI HE BING CHEN XUE-MIN CHEN 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2009年第4期311-317,共7页
Objective To investigate the effects of sodium selenite on telomerase activity, apoptosis and expression of TERT, c-myc and p53 in rat hepatocytes. Methods Selenium at doses of 2.5, 5.0, and 10 μmol/kg was given to S... Objective To investigate the effects of sodium selenite on telomerase activity, apoptosis and expression of TERT, c-myc and p53 in rat hepatocytes. Methods Selenium at doses of 2.5, 5.0, and 10 μmol/kg was given to SD rats by garage. In rat hepatocytes, telomerase activity was measured by the telomeric repeat amplification protocol (TRAP), apoptosis was detected by flow cytometry, and expressions of telomerase reverse transcriptase (TERT), c-myc and p53 were analyzed by reverse transcription-polymerase chain reaction (RT-PCR). c-Myc and P53 proteins were detected by immunochemistry. Results Selenium at doses of 2.5, 5.0, and 10 μmol/kg significantly increased hepatocellular telomerase activity and induced apoptosis in a dose-dependent manner. Although selenium at doses of 2.5, 5.0, and 10 μmol/kg displayed no obvious enhancing effect on the TERT mRNA expression in rat hepatocytes (P〉0.05), it significantly increased the c-myc mRNA and p53 mRNA expression at the dose of 10 μmol/kg (P〈0.05). Selenium at doses of 5.0 and 10 μmol/kg obviously increased the content of P53 protein in rat hepatocytes, but only at the dose of 10 μmol/kg, it significantly promoted the value of c-Myc protein in them. Conclusion Selenium can slightly increase telomerase activity and TERT expression, and significantly induce apoptosis and over-expression of c-myc and p53 at relatively high doses. The beneficial effects of selenium on senescence and aging may be mediated by telomerase activation and expression of TERT, c-myc, and p53 in rat hepatocytes. 展开更多
关键词 SELENIUM TELOMERASE Telomerase reverse transcriptase C-MYC P53
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Naturally occurring mutations in the reverse transcriptase region of hepatitis B virus polymerase from treatment-na?ve Korean patients infected with genotype C2 被引量:2
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作者 Ji-Eun Kim So-Young Lee +3 位作者 Hong Kim Ki-Jeong Kim Won-Hyeok Choe Bum-Joon Kim 《World Journal of Gastroenterology》 SCIE CAS 2017年第23期4222-4232,共11页
AIM To report naturally occurring mutations in the reverse transcriptase region(RT) of hepatitis B virus(HBV) polymerase from treatment na?ve Korean chronic patients infected with genotype C2.METHODS Here, full-length... AIM To report naturally occurring mutations in the reverse transcriptase region(RT) of hepatitis B virus(HBV) polymerase from treatment na?ve Korean chronic patients infected with genotype C2.METHODS Here, full-length HBV reverse transcriptase RT sequences were amplified and sequenced from 131 treatment na?ve Korean patients chronically infected with hepatitis B genotype C2. The patients had two distinct clinical statuses: 59 patients with chronic hepatitis(CH) and 72 patients with hepatocellular carcinoma(HCC). The deduced amino acids(AAs) at42 previously reported potential nucleos(t)ide analog resistance(NAr) mutation positions in the RT region were analyzed. RESULTS Potential NAr mutations involving 24 positions were found in 79 of the 131 patients(60.3%). Notably, AA substitutions at 2 positions(rt184 and rt204) involved in primary drug resistance and at 2 positions(rt80 and rt180) that functioned as secondary/compensatory mutations were detected in 10 patients(1 CH patient and 9 HCC patients) and 7 patients(1 CH and 6 HCC patients), respectively. The overall mutation frequencies in the HCC patients(3.17%, 96/3024 mutations) were significantly higher than the frequencies in the CH patients(2.09%, 52/2478 mutations)(P = 0.003). In addition, a total of 3 NAr positions, rt80, rt139 and rt204 were found to be significantly related to HCC from treatment na?ve Korean patients. CONCLUSION Our data showed that naturally occurring NAr mutations in South Korea might contribute to liver disease progression(particularly HCC generation) in chronic patients with genotype C2 infections. 展开更多
关键词 Hepatitis B virus POLYMERASE reverse transcriptase Potential nucleos(t)ide analog resistance Chronic hepatitis Hepatocellular carcinoma
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Identification and Characterization of Reverse Transcriptase Fragments of Long Interspersed Nuclear Elements (LINEs) in the <i>Morus notabilis</i>Genome 被引量:1
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作者 Bi Ma Youchao Xin +2 位作者 Lulu Kuang Fei Hou Ningjia He 《American Journal of Molecular Biology》 2017年第3期138-152,共15页
Reverse transcriptase (rt) fragments from LINE retrotransposons in the mulberry genome were analyzed in terms of heterogeneity, phylogeny, and chromosomal distribution. We amplified and characterized conserved domains... Reverse transcriptase (rt) fragments from LINE retrotransposons in the mulberry genome were analyzed in terms of heterogeneity, phylogeny, and chromosomal distribution. We amplified and characterized conserved domains of the rt using degenerate primer pairs. Sequence analyses indicated that the rt fragments were highly heterogeneous and rich in A/T bases. The sequence identity ranged from 31.8% to 99.4%. Based on sequence similarities, the rt fragments were categorized into eight groups. Furthermore, similar stop codon distribution patterns among a series of clones in the same group indicated that they underwent a similar evolutionary process. Interestingly, phylogenetic analyses of the rt fragments isolated from mulberry and 13 other plant species revealed that two distantly related taxa (mulberry and Paeonia suffruticosa) grouped together. It does not appear that this phenomenon resulted from horizontal transposable element transfer. Fluorescence in situ hybridization analysis revealed that most of the rt fragments were concentrated in the subtelomeric and pericentromeric regions of the mulberry chromosomes, but that these elements were not abundant in the mulberry genome. Future studies will focus on the potential roles of these elements in the subtelomeric and pericentromeric regions of the mulberry genome. 展开更多
关键词 iMorus notabilis LINE RETROTRANSPOSONS reverse transcriptase CHARACTERIZATION Fluorescence in site Hybridization
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Hepatitis C virus in human B lymphocytes transformed by Epstein-Barr virus in vitro by in situ reverse transcriptase-polymerase chain reaction 被引量:11
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作者 Ji Lin Cheng Bao Ling Liu Yi Zhang Wen Bin Tong Zheng Yan Bai Fang Feng Institute of Hepatology,Peoples Hospital,Medical Center of Beijing University,Beijing 10(X)44,China 《World Journal of Gastroenterology》 SCIE CAS CSCD 2001年第3期370-375,共6页
AIM: To study persistence and replication of hepatitis C virus (HCV) in patients' peripheral blood mononuclear cells (PBMC) cultured in vitro. METHODS: Epstein Barr virus (EBV) was used to transform the hepatitis ... AIM: To study persistence and replication of hepatitis C virus (HCV) in patients' peripheral blood mononuclear cells (PBMC) cultured in vitro. METHODS: Epstein Barr virus (EBV) was used to transform the hepatitis C virus from a HCV positive patient to permanent lymphoblastoid cell lines (LCL). Positive and negative HCV RNA strands of the cultured cells and growth media were detected by reverse transcriptase-polymerase chain reaction (RT-PCR) each month. Core and NS5 proteins of HCV were further tested using immunohistochemical SP method and in situ RT-PCR. RESULTS: HCV RNA positive strands were consistently detected the cultured cells for one year. The negative-strand RNA in LCL cells and the positive-strand RNA in supernatants were observed intermittently. Immunohistochemical results medicated expression of HCV NS3 and C proteins in LCL cytoplasm mostly. The positive signal of PCR product was dark blue and mainly localized to the LCL cytoplasm. The RT-PCR signal was eliminated by overnight RNase digestion but not DNase digestion. CONCLUSION: HCV may exist and remain functional in a cultured cell line for a long period. 展开更多
关键词 B-LYMPHOCYTES Cells Cultured Female HEPACIVIRUS development purification Herpesvirus 4 Human Humans Immunohistochemistry In Vitro Polymerase Chain Reaction RNA Viral Research Support Non-U.S. Gov't reverse transcriptase Polymerase Chain Reaction Transformation Genetic Viral Core Proteins Viral Nonstructural Proteins Virus Replication
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Molecular Modeling of Quinoline-Based Compounds as Potential Dual Inhibitors of Reverse Transcriptase and Integrase of HIV 被引量:1
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作者 Alberto Cabrera Leonor Huerta Hernández +1 位作者 Daniel Chávez José L. Medina-Franco 《Computational Molecular Bioscience》 2018年第3期122-148,共27页
As follow-up of our past publication?[1], we propose that quinolones (as part of the pyridinone family) are capable to increase the number of interactions with HIV reverse transcriptase (RT) or integrase (IN) by addin... As follow-up of our past publication?[1], we propose that quinolones (as part of the pyridinone family) are capable to increase the number of interactions with HIV reverse transcriptase (RT) or integrase (IN) by adding a halogen in position C-8 of aromatic portion of the quinolones. This addition could help with the activity of dual inhibitors of RT and IN. In this work, we add a chlorine atom with the rationale to identify in the docking simulations a halogen interaction with the oxygen in the near aminoacids in the binding pockets of RT and IN enzymes. Our docking studies started with RT and 320 structures. Later, we took 73 structures with good results in docking with RT. The structures that we choose contain ester or acids groups in C-3 due the structural similarity with groups in charge to interact with the Mg++ ions in Elvitegravir. In conclusion, we obtained 14 structures that could occupy the allosteric pocket of RT and could inhibit the catalytic activity of IN, for this reason could be dual inhibitors. A major perspective of this work is the synthesis and testing of the potential dual inhibitors designed. 展开更多
关键词 reverse transcriptase INTEGRASE QUINOLONE Dual Inhibitor DOCKING
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Interactive Study between Two Types of 1-[2-(Hydroxyethoxy)methyl] -6-naphthylmethylthymines and HIV-1 Reverse Transcriptase 被引量:4
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作者 孟歌 陈芬儿 +1 位作者 De Clercq Erik 戴惠芳 《过程工程学报》 CAS CSCD 北大核心 2003年第1期24-28,共5页
Two different types of 1-[2-(hydroxyethoxy)methyl]-6-naphthylmethylthymines have been designed, synthesized and evaluated for their anti-HIV-1 activities in different cells lines. The binding free energy (DG) includin... Two different types of 1-[2-(hydroxyethoxy)methyl]-6-naphthylmethylthymines have been designed, synthesized and evaluated for their anti-HIV-1 activities in different cells lines. The binding free energy (DG) including steric and electrostatic between the two different ligands and reverse transcriptase Non-Nucleoside Binding Pocket (NNBP) have been docked and calculated to evaluate their accommodation circumstance on a SGI work station. The DG and anti-HIV-1 activity has been correlated in order to guide further drug design, which showed that the steric binding effect dominated in the whole binding action between the compounds and reverse transcriptase (RT). The results showed that more negative DG led to higher activity of compounds. 展开更多
关键词 艾滋病毒 HIV-1 逆转录敏 6萘基HEPT类似物 自由结合能 抗病毒活性
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Screening of new non-nucleoside reverse transcriptase inhibitors of HIV-1 based on traditional Chinese medicines database
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作者 Tao Liu Ai Xiu Li +2 位作者 YOU Pan Miao Ke Zhu Wu Yi Ma 《Chinese Chemical Letters》 SCIE CAS CSCD 2009年第11期1386-1388,共3页
HIV- 1 RT is an important target for the treatment of AIDS. There are two major classes of antiviral agents that inhibit HIV- 1 RT have been identified, nucleoside RT inhibitors (NRTIs) and non-nucleoside RT inhibit... HIV- 1 RT is an important target for the treatment of AIDS. There are two major classes of antiviral agents that inhibit HIV- 1 RT have been identified, nucleoside RT inhibitors (NRTIs) and non-nucleoside RT inhibitors (NNRTIs). In this report, a noval class of non-nucleoside compound with potential RT inhibitory activity were found from the traditional Chinese medicines database (TCMD) using a combination of virtual screening, docking, molecular dynamic simulations, where results were ranked by scoring function of the docking tool. The result indicates that M4753 (a compound derived from TCMD) has not only the lowest bonding energy but also the best match in geometric conformation with the forthcoming NNRTIs. Accordingly M4753 might possibly become a promising lead compound of NNRTIs for AIDS therapy. 展开更多
关键词 Non-nucleoside reverse transcriptase inhibitors (NNrtIs) Traditional Chinese medicines database (TCMD) Virtual screening Molecular dock Molecular dynamic simulation
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RADIATION- INDUCED PROGRESSIVE DECREASING IN THE EXPRESSION OF REVERSE TRANSCRIPTASE GENE OF hEST2 AND TELOMERASE ACTIVITY
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作者 朱涵能 熊思东 程文英 《Chinese Medical Sciences Journal》 CAS CSCD 2001年第2期63-66,共4页
Objectives. In order to identify the relationship between telomerase and the biological effect of radiation injury,and investigate the role of human telomerase catalytic subunit gene (hEST2) reverse transcriptase(RT) ... Objectives. In order to identify the relationship between telomerase and the biological effect of radiation injury,and investigate the role of human telomerase catalytic subunit gene (hEST2) reverse transcriptase(RT) segment in the expression of telomerase activity. Methods. Tumor HeLa cells, KB cells and A431 cells were employed to measure the change in telomerase activity after 60Co- ray irradiation at RNA level and protein level. Quantitative PCR and Northern blotting were used to determine the expression of hEST2 RT segment that encodes seven motifs of the human telomeres, a PCR- based telomeric repeat amplification protocol (TRAP)was used to assay telomerase activity after exposure to radiation. Results. Both of telomerase activity and the expression hEST2 RT segment were decreased with increasing dosage of radiation. In addition, testing the expression of motifs domain is similar to the measurement of telomerase activity. Conclusion. The detection of the hEST2 RT segment by Northern blotting and quantitative PCR are new methods for testing telomerase activity. Furthermore, radiation can cause a dose- dependent decrease in telomerase activity. The effect of radiation on telomerase is one possible reason for the death of cancer cells after irradiation. 展开更多
关键词 TELOMERASE hEST2 reverse transcriptase segment IRRADIATION
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Development of Reverse Transcriptase Loop-Mediated Isothermal Amplification for Rapid and Visualized Detection of Classical Swine Fever Virus
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作者 QU Guang-gang YANG Hui +5 位作者 TANG Na WANG Jin-liang FU Shi-jun XIE Jin-wen YUE Fu-jie SHEN Zhi-qiang 《Animal Husbandry and Feed Science》 CAS 2010年第3期21-24,共4页
[ Objective] To develop a rapid and visualized detection method of classical swine fever virus (CSFV) using reverse transcriptase loopmediated isothermal amplification (RT-LAMP). [ Method ] A total of six special ... [ Objective] To develop a rapid and visualized detection method of classical swine fever virus (CSFV) using reverse transcriptase loopmediated isothermal amplification (RT-LAMP). [ Method ] A total of six special primers were designed based on the conserved sequences of CSFV gene. After optimizing, the reaction of RT-LAMP was carded out at 63℃ for 45 rain. The RT-LAMP products were analyzed by agarose gel electro- phoresis. The sensitivity, specificity and repeatability were verified, respectively. [ Result] The RT-LAMP method could be used for detecting CSFV rather than six generic viruses. The sensitivity of RT-LAMP was 100 times higher than that of RT-PCR. The detection of 27 clinical samples by RT- LAMP and RT-PCR showed that RT-LAMP is more reliable and convenient. [ Conclusion] The RT-LAMP method is sensitive and reliable for the detection of CSFV. 展开更多
关键词 Classical swine fever virus reverse transcriptase loop-mediated isothermal amplification RAPIDITY DIAGNOSIS
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Expression of Telomerase Reverse Transcriptase during the Malignant Transformation of Cadmium-Induced Cells
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作者 Min Wang Yixiong Lei 《Journal of Geoscience and Environment Protection》 2014年第2期129-133,共5页
The objective of the present study was to investigate human telomerase reverse transcriptase (hTERT) mRNA and protein expressions during the cadmium chloride-induced malignant transformation of human bronchial epithel... The objective of the present study was to investigate human telomerase reverse transcriptase (hTERT) mRNA and protein expressions during the cadmium chloride-induced malignant transformation of human bronchial epithelial (16HBE) cells. Fluorescence quantitative PCR (FQ-PCR) and Western blot analyses were performed to detect the hTERT mRNA and protein expressions in normal 16HBE cells, cadmium chloride-transformed 16HBE cells, and tumorigenic cells from nude mice inoculated with cadmium chloride-transformed 16HBE cells. Under the inner standard of GAPDH, the hTERT mRNA expression was significantly higher at different stages of malignant transformation (cadmium chloride-transformed 16HBE cells at passages 15 and 35 and tumorigenic cells from nude mice) than in normal 16HBE cells, and increased with the development of malignancy (P < 0.01). In addition, hTERT protein expression increased with the development of malignancy. These findings demonstrate that hTERT expression is related to cadmium chlorideinduced malignant transformation. Cadmium chloride-induced malignant transformation is involved in changes in the hTERT activity, and might be an early event in cadmium chloride-induced malignant transformation. 展开更多
关键词 CADMIUM Chloride Human BRONCHIAL EPITHELIAL Cells Malignant Transformation TELOMERASE reverse transcriptase
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Study on neoplasia of hydatidiform mole by detecting telomerase reverse transcriptase mRNA expression in peripheral blood mononuclear cells
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作者 Bao Lijun Xu Jing +3 位作者 Yang Shangwu Li Fen Zou Yuliang Huang Hui 《Journal of Medical Colleges of PLA(China)》 CAS 2010年第2期84-90,共7页
By setting up a real-time fluorescent quantitative RT-PCR assay to detect human telomerase reverse transcriptase (hTERT) mRNA in hydatidiform mole in peripheral blood mononuclear cells, to analyze the correlation be... By setting up a real-time fluorescent quantitative RT-PCR assay to detect human telomerase reverse transcriptase (hTERT) mRNA in hydatidiform mole in peripheral blood mononuclear cells, to analyze the correlation between the expression level of hTERT mRNA and the prognosis of hydatidiform mole, and to evaluate the clinic value of quantitative determination of hTERT mRNA in the diagnosis of hydatidiform mole. Methods: A real-time fluorescent quantitative RT-PCR (FQ RT-PCR) assay based on TaqMan fluorescence methodology and the Light-Cycler system was used to quantify the full range of hTERT mRNA copy numbers in 30 samples of hydatidiform mole and the neoplasia of hydatidiform mole. The normalized hTERT (NhTERT) was standardized by quantifying the number of GAPDH transcripts as internal control and expressed as 100x (hTERT/GAPDH) ratio. Based on the prognosis of the hydatidiform mole, the patients were divided into two groups: the experimental group and the control group, to compare the telomerase reverse transcriptase mRNA expression in peripheral blood mononuclear cells. Results: hTERT mRNA was both expressed in the peripheral blood mononuclear cells and pathological tissues in the mole experimental group and the control group. In the mole experimental group, the values were 6.31±0.32 and 6.24±0.44, respectively, and there was no significant difference between them (P〉0.05). But in the control group the values were 1.21±0.65 and 1.40±0.61, respectively, and there was no significant difference between them (P〉0.05) The values in experimental group was significantly higher than those in the control group (P〈0.01). Conclusion: Quantitative determination of hTERT mRNA by FQ RT-PCR is a rapid and sensitive method, hTERT in peripheral blood mononuclear cells may have potential use as a biomarker for the early detection of the prognosis of the hydatidiform mole. 展开更多
关键词 FQ rt-PCR Hydatidiform mole TELOMERASE reverse transcriptase
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