Photobiomodulation,originally used red and near-infrared lasers,can alter cellular metabolism.It has been demonstrated that the visible spectrum at 451-540 nm does not necessarily increase cell proliferation,near-infr...Photobiomodulation,originally used red and near-infrared lasers,can alter cellular metabolism.It has been demonstrated that the visible spectrum at 451-540 nm does not necessarily increase cell proliferation,near-infrared light promotes adipose stem cell proliferation and affects adipose stem cell migration,which is necessary for the cells homing to the site of injury.In this in vitro study,we explored the potential of adipose-derived stem cells to differentiate into neurons for future translational regenerative treatments in neurodegenerative disorders and brain injuries.We investigated the effects of various biological and chemical inducers on trans-differentiation and evaluated the impact of photobiomodulation using 825 nm near-infrared and 525 nm green laser light at 5 J/cm2.As adipose-derived stem cells can be used in autologous grafting and photobiomodulation has been shown to have biostimulatory effects.Our findings reveal that adipose-derived stem cells can indeed trans-differentiate into neuronal cells when exposed to inducers,with pre-induced cells exhibiting higher rates of proliferation and trans-differentiation compared with the control group.Interestingly,green laser light stimulation led to notable morphological changes indicative of enhanced trans-differentiation,while near-infrared photobiomodulation notably increased the expression of neuronal markers.Through biochemical analysis and enzyme-linked immunosorbent assays,we observed marked improvements in viability,proliferation,membrane permeability,and mitochondrial membrane potential,as well as increased protein levels of neuron-specific enolase and ciliary neurotrophic factor.Overall,our results demonstrate the efficacy of photobiomodulation in enhancing the trans-differentiation ability of adipose-derived stem cells,offering promising prospects for their use in regenerative medicine for neurodegenerative disorders and brain injuries.展开更多
话古文古文与历史往往有着干丝万缕的联系,不同朝代的古文,折射出不同朝代的社会环境与人文历史。同学们,让我们一起跟随画作,通过阅读古文,感受不同朝代的魅力吧!ProfileofTheImmortalsbytheRiver Yang Shen was a famous poet of the ...话古文古文与历史往往有着干丝万缕的联系,不同朝代的古文,折射出不同朝代的社会环境与人文历史。同学们,让我们一起跟随画作,通过阅读古文,感受不同朝代的魅力吧!ProfileofTheImmortalsbytheRiver Yang Shen was a famous poet of the Ming Dynasty.He used to be an official but was later exiled(流放)to Yunnan.He spent the rest of his life there and wrote many Ci poems includingthis one.展开更多
Through analyzing the relationship between immortal cultures and tourist activities, the authors proposed that birth of immortal thought was closely related to early tourist activities. The core idea of immortal cultu...Through analyzing the relationship between immortal cultures and tourist activities, the authors proposed that birth of immortal thought was closely related to early tourist activities. The core idea of immortal cultures was in conformity with modern leisure cultures. Tourist resources in Ancient Xianshi Township were re-explored, and application of immortal cultures in tourism development of the town was studied. The authors proposed that both "immortal" and "salt" should be valued in the tourism development of ancient Xianshi Township, interaction and integration of immortal stories, immortal traces and scenic areas should be stressed in the application of immortal cultures, so as to incorporate "immortal bath" and modern salt bath, and to combine creation of fairyland with modern sightseeing and leisure agriculture.展开更多
Shakespeare’s Sonnet 12 is about the destructive effect of time on the beauty of the nature as well as human beings and how one can be immortal. This paper analyzes the theme of this sonnet and the way the poet prese...Shakespeare’s Sonnet 12 is about the destructive effect of time on the beauty of the nature as well as human beings and how one can be immortal. This paper analyzes the theme of this sonnet and the way the poet presents this theme.展开更多
Telomerase has fundamental roles in bypassing cellular aging and in cancer progression by maintaining telomere homeostasis and integrity. However, recent studies have led some investigators to suggest novel biochemica...Telomerase has fundamental roles in bypassing cellular aging and in cancer progression by maintaining telomere homeostasis and integrity. However, recent studies have led some investigators to suggest novel biochemical properties of telomerase in several essential cell signaling pathways without apparent involvement of its well established function in telomere maintenance. These observations may further enhance our understanding of the molecular actions of telomerase in aging and cancer. This review will provide an update on the extracurricular activities of telomerase in apoptosis, DNA repair, stern cell function, and in the regulation of gene expression.展开更多
AIM: To construct and evaluate the functionality of a choanoid-fluidized bed bioreactor (CFBB) based on microencapsulated immortalized human hepatocytes.
Nasopharyngeal carcinoma (NPC) is a common cancer in Southern China and Southeast Asia. The disease is a poorly differentiated carcinoma without effective cure, and the mechanism underlying its development remains l...Nasopharyngeal carcinoma (NPC) is a common cancer in Southern China and Southeast Asia. The disease is a poorly differentiated carcinoma without effective cure, and the mechanism underlying its development remains largely unknown. Of several factors identified in NPC aetiology in recent years, Epstein-Barr virus (EBV) infection has emerged to be most important. In almost all NPC cells, EBV uses several intracellular mechanisms to cause oncogenic evolution of the infected cells. One such mechanism by which EBV infection induces cellular immortalization is believed to be through the activation of telomerase, an enzyme that is normally repressed but becomes activated during cancer development. Studies show that greater than 85% of primary NPC display high telomerase activity by mechanisms involving EBV infection, consistent with the notion that EBV is commonly involved in inducing cell immortalization. More recently, different EBV proteins have been shown to activate or inhibit the human telomerase reverse transcriptase gene, by modulating intracellular signalling pathways. These findings suggest a new model with a number of challenges towards our understanding, molecular targeting and therapeutic intervention in NPC.展开更多
Immortalized F2 population of rice (Oryza sativa L.) was developed by randomly mating F1 among recombinant inbred (RI) lines derived from (Zhenshan 97B×Minghui 63),which allowed replications within and across env...Immortalized F2 population of rice (Oryza sativa L.) was developed by randomly mating F1 among recombinant inbred (RI) lines derived from (Zhenshan 97B×Minghui 63),which allowed replications within and across environments.QTL (quantitative trait loci) mapping analysis on kilo-grain weight of immortalized F2 population was performed by using newly developed software for QTL mapping,QTL Mapper 2.0. Eleven distinctly digenic epistatic loci included a total of 15 QTL were located on eight chromosomes.QTL main effects of additive,dominance,and additive×additive,additive×dominance,and dominance×dominance interactions were estimated.Interaction effects between QTL main effects and environments (QE) were predicted.Less than 40% of single effects,most of which were additive effects,for identified QTL were significant at 5% level.The directional difference for QTL main effects suggested that these QTL were distributed in parents in the repulsion phase.This should make it feasible to improve kilo-grain weight of both parents by selecting appropriate new recombinants. Only few of the QE interaction effects were significant.Application prospect for QTL mapping achievements in genetic breeding was discussed.展开更多
Objective: To establish normally conditionally-immortalized human umbilical vein endothelial cells (HUVECs) by ectopic expression of the human telomerase catalytic enzyme (hTERT) and simian virus 40 large T (SV40 LT) ...Objective: To establish normally conditionally-immortalized human umbilical vein endothelial cells (HUVECs) by ectopic expression of the human telomerase catalytic enzyme (hTERT) and simian virus 40 large T (SV40 LT) antigen. Methods:Primary HUVECs were transfected with recombinant retrovirus containing hTERT or SV40 LT respectively. Subsequently drug resistant cell clones were screened and expanded for further studies. Endothelial cell biomarkers were confirmed by examination.Results: The morphological phenotype of the transfected cells was similar to the non-transfected cells. Von Willebrand factor,hTERT and SV40 LT could be detected in transfected HUVECs. Moreover, higher telomerase activity in transfected cells was maintained for over 50 population doublings compared with only low level of endogenous telomerase transiently at early population doublings in primary HUVECs. When exposed to TNF-α (tumor necrosis factor-α), the expression of E-selectin in transfected cells was significantly up-regulated, but no alteration of endothelial lipase was found. Conclusion: Ectopic coexpression of hTERT and SV40 LT can effectively immortalize HUVECs without tumorigenicity in vitro. Immortalized HUVECs may be an ideal target of further molecular function studies.展开更多
BACKGROUND: Orthotopic liver transplantation (OLT) is the most effective therapy for liver failure. However, OLT is severely limited by the shortage of liver donors. Bioartificial liver (BAL) shows great potential as ...BACKGROUND: Orthotopic liver transplantation (OLT) is the most effective therapy for liver failure. However, OLT is severely limited by the shortage of liver donors. Bioartificial liver (BAL) shows great potential as an alternative therapy for liver failure In recent years, progress has been made in BAL regarding genetically engineered cell lines, immortalized human hepatocytes, methods for preserving the phenotype of primary human hepatocytes, and other functional hepatocytes derived from stem cells. DATA SOURCES: A systematic search of PubMed and ISI Web of Science was performed to identify relevant studies in English language literature using the Key words such as liver failure bioartificial liver, hepatocyte, stem cells, differentiation, and immortalization. More than 200 articles related to the cell sources of hepatocyte in BAL were systematically reviewed. RESULTS: Methods for preserving the phenotype of primary human hepatocytes have been successfully developed. Many genetically engineered cell lines and immortalized human hepatocytes have also been established. Among these cell lines the incorporation of BAL with GS-HepG2 cells or alginate encapsulated HepG2 cells could prolong the survival time and improve pathophysiological parameters in an animal model of liver failure. The cBAL111 cells were evaluated using the AMC-BAL bioreactor, which could eliminate ammonia and lidocaine, and produce albumin. Importantly, BAL loading with HepLi-4 cells could significantly improve the blood biochemical parameters, and prolong the survival time in pigs with liver failure. Other functional hepatocytes differentiated from stem cells, such as human liver progenitor cells, have been successfully achieved. CONCLUSIONS: Aside from genetically modified liver cell lines and immortalized human hepatocytes, other functionalhepatocytes derived from stem cells show great potential as cell sources for BAL. BAL with safe and effective liver cells may be achieved for clinical liver failure in the near future.展开更多
AIM: To establish a method for the reversible immortalization of human hepatocytes, which may offer a good and safe source of hepatocytes for practical applications.
AIM: To develop a hepatocyte cell line, we immortalized primary porcine hepatocytes with a retroviral vector SSR#69 containing the Simian Virus 40 T antigen (SV40T ag). METHODS: We first established a method of porcin...AIM: To develop a hepatocyte cell line, we immortalized primary porcine hepatocytes with a retroviral vector SSR#69 containing the Simian Virus 40 T antigen (SV40T ag). METHODS: We first established a method of porcine hepatocyte isolation with a modified four-step retrograde perfusion technique. Then the porcine hepatocytes were immortalized with retroviral vector SSR#69 expressing SV40T and hygromycin-resistance genes flanked by paired loxP recombination targets. SV40T cDNA in the expanded cells was subsequently excised by Cre/LoxP site-specific recombination. RESULTS: The resultant hepatocytes with high viability (97%) were successfully immortalized with retroviral vector SSR#69. One of the immortalized clones showed the typical morphological appearance, TJPH-1, and was selected by clone rings and expanded in culture. After excision of the SV40T gene with Cre-recombinase, cells stopped growing. The population of reverted cells exhibited the characteristics of differentiated hepatocytes. CONCLUSION: In conclusion, we herein describe a modified method of hepatocyte isolation and subsequently established a porcine hepatocyte cell line mediated by retroviral transfer and site-specific recombination.展开更多
Objective Cytochrome P450 2E1 (CYP2E1) is an important metabolizing enzyme involved in oxidative stress responses to benzene, a chemical associated with bone marrow toxicity and leukemia, We aimed to identify the CY...Objective Cytochrome P450 2E1 (CYP2E1) is an important metabolizing enzyme involved in oxidative stress responses to benzene, a chemical associated with bone marrow toxicity and leukemia, We aimed to identify the CYP2E1 genetic biomarkers of susceptibility to benzene toxicity in support of environmental and occupational exposure prevention, and to test whether a model using immortal human lymphocytes might be an efficient tool for detecting genetic biomarkers. Methods Immortalized human lymphocyte cell lines with independent genotypes on four CYP2E1 SNP sites were induced with 0.01% phenol, a metabolite of benzene. CYP2E1 gene function was evaluated by mRNA expression and enzyme activity. DNA damage was measured by Single-Cell Gel Electrophoresis (SCGE). Results Among the four SNPs, cells with rs2070673TT and rs2030920CC showed higher levels of ~YP2E1 transcription and enzymatic activity than the other genotypes in the same SNP site. Cells with higher gene expression genotypes also showed higher comet rates compared with lower gene expression genotypes. Conclusion These results suggest that CYP2E1 rs2070673 and rs2030920 might be the genetic biomarkers of susceptibility to benzene toxicity and that the immortalized human lymphocytes model might be an efficient tool for the detection of genetic biomarkers of susceptibility to chemicals.展开更多
AIM: To investigate into the potential involvement of pyrin containing 3 gene(NLRP3), a member of the nucleotide-binding oligomerization domain-like receptors with cytosolic pattern recognition, in the host defense of...AIM: To investigate into the potential involvement of pyrin containing 3 gene(NLRP3), a member of the nucleotide-binding oligomerization domain-like receptors with cytosolic pattern recognition, in the host defense of corneas against viruses.METHODS: The herpes viral keratitis model was utilized in BALB/c mice with inoculation of herpes simplex virus-1(HSV-1). Corneal tissues removed during therapy of patients with viral keratitis as well as a Simian vacuolating virus 40(SV40)-immortalized human corneal epithelial cell line were also examined.Immunohistochemistry was used to detect NLRP3 in these subjects, focusing on their distribution in tissue or cells. Western blot was used to measure the level of NLRP3 and another two related molecules in NLPR3 inflammasome, namely caspase-1 and IL-1β.RESULTS: The NLRP3 activation induced by HSV-1infection in corneas was accompanied with redistribution of NLRP3 from the cytoplasm to the nucleus in both murine and human corneal epithelial cells. Furthermore,in the SV40-immortalized human corneal epithelial cells,NLRP3 was exclusively located in the nucleus, and treatment of the cells with high concentration of extracellular potassium(known as an inhibitor of NLRP3activation) effectively drove NLRP3 back to the cytoplasm as reflected by both immunohistochemistry and Western blot.· CONCLUSION: It is proposed that herpes virus infection activates and causes redistribution of NLRP3 to nuclei. Whether this NLRP3 translocation occurs with other viral infections and in other cell types merit further study.展开更多
Background:Spermatogonial stem cells(SSCs)are capable of both self-renewal and differentiation to mature functional spermatozoa,being the only adult stem cells in the males that can transmit genetic information to the...Background:Spermatogonial stem cells(SSCs)are capable of both self-renewal and differentiation to mature functional spermatozoa,being the only adult stem cells in the males that can transmit genetic information to the next generation.Porcine SSCs hold great value in transgenic pig production and in establishment of porcine models for regenerative medicine.However,studies and applications of porcine SSCs have been greatly hampered by the low number of SSCs in the testis as well as the lack of an ideal stable long-term culture system to propagate porcine SSCs perpetually.Results:In the present study,by lentiviral transduction of plasmids expressing the simian virus 40(SV40)large T antigen into porcine primary SSCs,we developed two immortalized cell lines with porcine SSC attributes.The established cell lines,with the expression of porcine SSC and germ cell markers UCHL1,PLZF,THY1,VASA and DAZL,could respond to retinoic acid(RA),and could colonize the recipient mouse testis without tumor formation after transplantation.The cell lines displayed infinite proliferation potential,and have now been cultured for more than 7 months and passaged for over 35 times without morphological abnormalities.Conclusions:We have for the first time established porcine SSC lines that could provide abundant cell sources for mechanistic studies on porcine SSC self-renewal and differentiation,thereby facilitating development of an optimal long-term culture system for porcine primary SSCs and their application to animal husbandry and medicine.展开更多
Conophylline, is a bis (indole) alkaloid consisting of two pentacyclic aspidosperma skeletons, isolated from Tabernaemontana divaricata, which has been found to induce β-cell differentiation in rat pancreatic acina...Conophylline, is a bis (indole) alkaloid consisting of two pentacyclic aspidosperma skeletons, isolated from Tabernaemontana divaricata, which has been found to induce β-cell differentiation in rat pancreatic acinar carcinoma cells and in cultured rat pancreatic tissue. However, the precise role of conophylline in the growth and survival of immortalized pancreatic mesenchymal stem cells (iPMSCs) derived from fetal porcine pancreas were not understood at present. To determine whether this molecule is involved in controlling the proliferation of iPMSCs, we examined the effects of conophylline on iPMSCs. We found that conophylline can robustly stimulate iPMSCs proliferation, even promote their potential differentiation into islet-like clusters analyzed by cell counting, morphology, RT-PCR and real-time PCR, Western blotting, glucose-stimulated insulin release and insulin content analysis. The effects of conophylline were inhibited by LY294002, which is the inhibitor of the PI3K pathway. These results suggest that conophylline plays a key role in the regulation of cell mass proliferation, maintenance of the undifferentiated state of iPMSCs and also promotes iPMSCs differentiated into insulin-producing cells.展开更多
AIM: To reserve the rare Chinese familial adenomas polyp (FAP) family resource and to investigate the clinical features of FAP in Chinese for its diagnosis. METHODS: Clinical features of patients with FAP were inv...AIM: To reserve the rare Chinese familial adenomas polyp (FAP) family resource and to investigate the clinical features of FAP in Chinese for its diagnosis. METHODS: Clinical features of patients with FAP were investigated. If there is any question, their medical records were verified. Blood sample was taken and lymphocyte immortal cell lines were established with modified EB-transformation methods. Congenital hypertrophy of retinal pigment epithelium (CHRPE) was checked by an experienced ophthalmologist. RESULTS: Twenty seven families including 21 classical FAP (CFAP) families, 3 attenuated FAP (AFAP) families, and 3 suspected AFAP families were investigated. A total of 116 lymphocyte immortal cell lines were established from 26 families. In all the FAP families, colorectal cancer occurred at the mean age of 42.84 years. Of the 16 families checked, 15 (93.75%) had CHRPE. The mean number of patients suffering from colorectal neoplasm was 3.14 in CFAP families and 2.0 in AFAP families (P 〈 0.01). The mean oldest age at diagnosis of FAP was 41.75 years in CFAP families, and 58.67 years in AFAP families, respectively (P 〈 0.01). Mean age of development of colorectal cancer was 42.23 in CFAP and 57.33 years old in AFAP (P 〈 0.01). Mean of the earliest age at diagnosis of FAP was 29.95 years in the FAP families with a positive family history and 46.80 years in the FAP families with a negative family history (P 〈 0.01). The ratio of extra-intestinal tumors to colorectal neoplasms was different in the two kinds of families with positive and negative family history (P 〈 0.01). CONCLUSION: Additional use of ciclosporin will effectively improve to establish lymphocyte immortal cell lines with modified EB- transformation methods. In Chinese FAP, there was a high frequency of CHRPE, and a later age at diagnosis and a later age of development of colorectal cancer in AFAR And earlier age at diagnosis in FAP with positive family history was also found that will help to diagnose various kinds of FAP in Chinese.展开更多
基金supported by the National Research Foundation(NRF)S&F-Scarce Skills Postdoctoral Fellowship,No.120752(to AC)the Global Excellence and Stature,Fourth Industrial Revolution(GES 4.0)Postgraduate Scholarship(to MJR)the South African Research Chairs Initiative of the Department of Science and Technology and National Research Foundation of South Africa(SARChI/NRF-DST),No.146290(to DDS and HA).
文摘Photobiomodulation,originally used red and near-infrared lasers,can alter cellular metabolism.It has been demonstrated that the visible spectrum at 451-540 nm does not necessarily increase cell proliferation,near-infrared light promotes adipose stem cell proliferation and affects adipose stem cell migration,which is necessary for the cells homing to the site of injury.In this in vitro study,we explored the potential of adipose-derived stem cells to differentiate into neurons for future translational regenerative treatments in neurodegenerative disorders and brain injuries.We investigated the effects of various biological and chemical inducers on trans-differentiation and evaluated the impact of photobiomodulation using 825 nm near-infrared and 525 nm green laser light at 5 J/cm2.As adipose-derived stem cells can be used in autologous grafting and photobiomodulation has been shown to have biostimulatory effects.Our findings reveal that adipose-derived stem cells can indeed trans-differentiate into neuronal cells when exposed to inducers,with pre-induced cells exhibiting higher rates of proliferation and trans-differentiation compared with the control group.Interestingly,green laser light stimulation led to notable morphological changes indicative of enhanced trans-differentiation,while near-infrared photobiomodulation notably increased the expression of neuronal markers.Through biochemical analysis and enzyme-linked immunosorbent assays,we observed marked improvements in viability,proliferation,membrane permeability,and mitochondrial membrane potential,as well as increased protein levels of neuron-specific enolase and ciliary neurotrophic factor.Overall,our results demonstrate the efficacy of photobiomodulation in enhancing the trans-differentiation ability of adipose-derived stem cells,offering promising prospects for their use in regenerative medicine for neurodegenerative disorders and brain injuries.
文摘话古文古文与历史往往有着干丝万缕的联系,不同朝代的古文,折射出不同朝代的社会环境与人文历史。同学们,让我们一起跟随画作,通过阅读古文,感受不同朝代的魅力吧!ProfileofTheImmortalsbytheRiver Yang Shen was a famous poet of the Ming Dynasty.He used to be an official but was later exiled(流放)to Yunnan.He spent the rest of his life there and wrote many Ci poems includingthis one.
文摘Through analyzing the relationship between immortal cultures and tourist activities, the authors proposed that birth of immortal thought was closely related to early tourist activities. The core idea of immortal cultures was in conformity with modern leisure cultures. Tourist resources in Ancient Xianshi Township were re-explored, and application of immortal cultures in tourism development of the town was studied. The authors proposed that both "immortal" and "salt" should be valued in the tourism development of ancient Xianshi Township, interaction and integration of immortal stories, immortal traces and scenic areas should be stressed in the application of immortal cultures, so as to incorporate "immortal bath" and modern salt bath, and to combine creation of fairyland with modern sightseeing and leisure agriculture.
文摘Shakespeare’s Sonnet 12 is about the destructive effect of time on the beauty of the nature as well as human beings and how one can be immortal. This paper analyzes the theme of this sonnet and the way the poet presents this theme.
基金Acknowledgments Research in author's lab was supported in part by a grant from the National Natural Science Foundation of China (No. 30671065), the Research Fund for the Doctoral Program of High Education (No. 20060027008), and the National Important Basic Research Project (No. 2007CB507402) to Yusheng Cong. Support from NASA grants NNJ06HD92G and NNJ05HD36G (JWS) is acknowledged.
文摘Telomerase has fundamental roles in bypassing cellular aging and in cancer progression by maintaining telomere homeostasis and integrity. However, recent studies have led some investigators to suggest novel biochemical properties of telomerase in several essential cell signaling pathways without apparent involvement of its well established function in telomere maintenance. These observations may further enhance our understanding of the molecular actions of telomerase in aging and cancer. This review will provide an update on the extracurricular activities of telomerase in apoptosis, DNA repair, stern cell function, and in the regulation of gene expression.
基金Supported by The Grants from the National Scientific and Technological Major Project of China,No.2011ZX10004-901,No.2013ZX10004904the National Science and Technology Major Project,No.2012ZX10002006
文摘AIM: To construct and evaluate the functionality of a choanoid-fluidized bed bioreactor (CFBB) based on microencapsulated immortalized human hepatocytes.
文摘Nasopharyngeal carcinoma (NPC) is a common cancer in Southern China and Southeast Asia. The disease is a poorly differentiated carcinoma without effective cure, and the mechanism underlying its development remains largely unknown. Of several factors identified in NPC aetiology in recent years, Epstein-Barr virus (EBV) infection has emerged to be most important. In almost all NPC cells, EBV uses several intracellular mechanisms to cause oncogenic evolution of the infected cells. One such mechanism by which EBV infection induces cellular immortalization is believed to be through the activation of telomerase, an enzyme that is normally repressed but becomes activated during cancer development. Studies show that greater than 85% of primary NPC display high telomerase activity by mechanisms involving EBV infection, consistent with the notion that EBV is commonly involved in inducing cell immortalization. More recently, different EBV proteins have been shown to activate or inhibit the human telomerase reverse transcriptase gene, by modulating intracellular signalling pathways. These findings suggest a new model with a number of challenges towards our understanding, molecular targeting and therapeutic intervention in NPC.
文摘Immortalized F2 population of rice (Oryza sativa L.) was developed by randomly mating F1 among recombinant inbred (RI) lines derived from (Zhenshan 97B×Minghui 63),which allowed replications within and across environments.QTL (quantitative trait loci) mapping analysis on kilo-grain weight of immortalized F2 population was performed by using newly developed software for QTL mapping,QTL Mapper 2.0. Eleven distinctly digenic epistatic loci included a total of 15 QTL were located on eight chromosomes.QTL main effects of additive,dominance,and additive×additive,additive×dominance,and dominance×dominance interactions were estimated.Interaction effects between QTL main effects and environments (QE) were predicted.Less than 40% of single effects,most of which were additive effects,for identified QTL were significant at 5% level.The directional difference for QTL main effects suggested that these QTL were distributed in parents in the repulsion phase.This should make it feasible to improve kilo-grain weight of both parents by selecting appropriate new recombinants. Only few of the QE interaction effects were significant.Application prospect for QTL mapping achievements in genetic breeding was discussed.
基金Project (No. 021110240) supported by grants from the Foundation of the Department of Science and Technology of Zhejiang Province,China
文摘Objective: To establish normally conditionally-immortalized human umbilical vein endothelial cells (HUVECs) by ectopic expression of the human telomerase catalytic enzyme (hTERT) and simian virus 40 large T (SV40 LT) antigen. Methods:Primary HUVECs were transfected with recombinant retrovirus containing hTERT or SV40 LT respectively. Subsequently drug resistant cell clones were screened and expanded for further studies. Endothelial cell biomarkers were confirmed by examination.Results: The morphological phenotype of the transfected cells was similar to the non-transfected cells. Von Willebrand factor,hTERT and SV40 LT could be detected in transfected HUVECs. Moreover, higher telomerase activity in transfected cells was maintained for over 50 population doublings compared with only low level of endogenous telomerase transiently at early population doublings in primary HUVECs. When exposed to TNF-α (tumor necrosis factor-α), the expression of E-selectin in transfected cells was significantly up-regulated, but no alteration of endothelial lipase was found. Conclusion: Ectopic coexpression of hTERT and SV40 LT can effectively immortalize HUVECs without tumorigenicity in vitro. Immortalized HUVECs may be an ideal target of further molecular function studies.
基金supported by grants from the Chinese High-Tech Research & Development (863) Program (2011AA020104)Science Fund for Creative Research Groups of the National Natural Science Foundation of China (81121002)+1 种基金the Fundamental Research Funds for the Central Universitiesthe Technology Group Project for Infectious Disease Control of Zhejiang Province (2009R50041)
文摘BACKGROUND: Orthotopic liver transplantation (OLT) is the most effective therapy for liver failure. However, OLT is severely limited by the shortage of liver donors. Bioartificial liver (BAL) shows great potential as an alternative therapy for liver failure In recent years, progress has been made in BAL regarding genetically engineered cell lines, immortalized human hepatocytes, methods for preserving the phenotype of primary human hepatocytes, and other functional hepatocytes derived from stem cells. DATA SOURCES: A systematic search of PubMed and ISI Web of Science was performed to identify relevant studies in English language literature using the Key words such as liver failure bioartificial liver, hepatocyte, stem cells, differentiation, and immortalization. More than 200 articles related to the cell sources of hepatocyte in BAL were systematically reviewed. RESULTS: Methods for preserving the phenotype of primary human hepatocytes have been successfully developed. Many genetically engineered cell lines and immortalized human hepatocytes have also been established. Among these cell lines the incorporation of BAL with GS-HepG2 cells or alginate encapsulated HepG2 cells could prolong the survival time and improve pathophysiological parameters in an animal model of liver failure. The cBAL111 cells were evaluated using the AMC-BAL bioreactor, which could eliminate ammonia and lidocaine, and produce albumin. Importantly, BAL loading with HepLi-4 cells could significantly improve the blood biochemical parameters, and prolong the survival time in pigs with liver failure. Other functional hepatocytes differentiated from stem cells, such as human liver progenitor cells, have been successfully achieved. CONCLUSIONS: Aside from genetically modified liver cell lines and immortalized human hepatocytes, other functionalhepatocytes derived from stem cells show great potential as cell sources for BAL. BAL with safe and effective liver cells may be achieved for clinical liver failure in the near future.
基金Supported by Major Scientific and Technological Project of Shandong Province,No.201221019Cisco Clinical Oncology Research Fund and Bayer Schering Cancer Research Fund,No.Y-B2012-011
文摘AIM: To establish a method for the reversible immortalization of human hepatocytes, which may offer a good and safe source of hepatocytes for practical applications.
基金Supported by The Major Scientific and Technological Project of Hubei Province, No. 2007ABD005
文摘AIM: To develop a hepatocyte cell line, we immortalized primary porcine hepatocytes with a retroviral vector SSR#69 containing the Simian Virus 40 T antigen (SV40T ag). METHODS: We first established a method of porcine hepatocyte isolation with a modified four-step retrograde perfusion technique. Then the porcine hepatocytes were immortalized with retroviral vector SSR#69 expressing SV40T and hygromycin-resistance genes flanked by paired loxP recombination targets. SV40T cDNA in the expanded cells was subsequently excised by Cre/LoxP site-specific recombination. RESULTS: The resultant hepatocytes with high viability (97%) were successfully immortalized with retroviral vector SSR#69. One of the immortalized clones showed the typical morphological appearance, TJPH-1, and was selected by clone rings and expanded in culture. After excision of the SV40T gene with Cre-recombinase, cells stopped growing. The population of reverted cells exhibited the characteristics of differentiated hepatocytes. CONCLUSION: In conclusion, we herein describe a modified method of hepatocyte isolation and subsequently established a porcine hepatocyte cell line mediated by retroviral transfer and site-specific recombination.
基金supported by the National Natural Science Foundation of China (Grant No: 30671731, 30901168)the Doctoral Program of Higher Education of China (Grant No: 20070286069)
文摘Objective Cytochrome P450 2E1 (CYP2E1) is an important metabolizing enzyme involved in oxidative stress responses to benzene, a chemical associated with bone marrow toxicity and leukemia, We aimed to identify the CYP2E1 genetic biomarkers of susceptibility to benzene toxicity in support of environmental and occupational exposure prevention, and to test whether a model using immortal human lymphocytes might be an efficient tool for detecting genetic biomarkers. Methods Immortalized human lymphocyte cell lines with independent genotypes on four CYP2E1 SNP sites were induced with 0.01% phenol, a metabolite of benzene. CYP2E1 gene function was evaluated by mRNA expression and enzyme activity. DNA damage was measured by Single-Cell Gel Electrophoresis (SCGE). Results Among the four SNPs, cells with rs2070673TT and rs2030920CC showed higher levels of ~YP2E1 transcription and enzymatic activity than the other genotypes in the same SNP site. Cells with higher gene expression genotypes also showed higher comet rates compared with lower gene expression genotypes. Conclusion These results suggest that CYP2E1 rs2070673 and rs2030920 might be the genetic biomarkers of susceptibility to benzene toxicity and that the immortalized human lymphocytes model might be an efficient tool for the detection of genetic biomarkers of susceptibility to chemicals.
基金Supported by National Natural Science Foundation of China(No.81273212,81100651)Project of Science and Technology of Shandong Province(No.2014GSF118044)
文摘AIM: To investigate into the potential involvement of pyrin containing 3 gene(NLRP3), a member of the nucleotide-binding oligomerization domain-like receptors with cytosolic pattern recognition, in the host defense of corneas against viruses.METHODS: The herpes viral keratitis model was utilized in BALB/c mice with inoculation of herpes simplex virus-1(HSV-1). Corneal tissues removed during therapy of patients with viral keratitis as well as a Simian vacuolating virus 40(SV40)-immortalized human corneal epithelial cell line were also examined.Immunohistochemistry was used to detect NLRP3 in these subjects, focusing on their distribution in tissue or cells. Western blot was used to measure the level of NLRP3 and another two related molecules in NLPR3 inflammasome, namely caspase-1 and IL-1β.RESULTS: The NLRP3 activation induced by HSV-1infection in corneas was accompanied with redistribution of NLRP3 from the cytoplasm to the nucleus in both murine and human corneal epithelial cells. Furthermore,in the SV40-immortalized human corneal epithelial cells,NLRP3 was exclusively located in the nucleus, and treatment of the cells with high concentration of extracellular potassium(known as an inhibitor of NLRP3activation) effectively drove NLRP3 back to the cytoplasm as reflected by both immunohistochemistry and Western blot.· CONCLUSION: It is proposed that herpes virus infection activates and causes redistribution of NLRP3 to nuclei. Whether this NLRP3 translocation occurs with other viral infections and in other cell types merit further study.
基金This study was supported by the National Natural Science Foundation of China(Grant No.31572401,31772605)to W.Z.the Open Fund of Farm Animal Genetic Resources Exploration and Innovation Key Laboratory of Sichuan Province(Grant No.SNDK-KF-201804)Young Talent fund of University Association for Science and Technology in Shaanxi,China(Grant No.20180204)and a startup fund from Northwest A&F University(Grant No.2452018037)to Y.Z.
文摘Background:Spermatogonial stem cells(SSCs)are capable of both self-renewal and differentiation to mature functional spermatozoa,being the only adult stem cells in the males that can transmit genetic information to the next generation.Porcine SSCs hold great value in transgenic pig production and in establishment of porcine models for regenerative medicine.However,studies and applications of porcine SSCs have been greatly hampered by the low number of SSCs in the testis as well as the lack of an ideal stable long-term culture system to propagate porcine SSCs perpetually.Results:In the present study,by lentiviral transduction of plasmids expressing the simian virus 40(SV40)large T antigen into porcine primary SSCs,we developed two immortalized cell lines with porcine SSC attributes.The established cell lines,with the expression of porcine SSC and germ cell markers UCHL1,PLZF,THY1,VASA and DAZL,could respond to retinoic acid(RA),and could colonize the recipient mouse testis without tumor formation after transplantation.The cell lines displayed infinite proliferation potential,and have now been cultured for more than 7 months and passaged for over 35 times without morphological abnormalities.Conclusions:We have for the first time established porcine SSC lines that could provide abundant cell sources for mechanistic studies on porcine SSC self-renewal and differentiation,thereby facilitating development of an optimal long-term culture system for porcine primary SSCs and their application to animal husbandry and medicine.
基金supported by the grants from the National Natural Science Foundation of China(31272518, 31101775, 30972097)the Doctoral Fund of Ministry of Education of China (20100204120020)+4 种基金the Program for New Century Excellent Talents of State Ministry of Education (NCET-09-0654)the Scientific Research Program of Shaanxi Province (2011K02-06, 2008K02-05)the Scientific Research Program of Shaanxi Province, China(2011K02-06)the Fundamental Research Funds for the Central Universities, China (QN2011012)the Graduate Education Innovation Projects of Henan University of Technology, China (11YJCX45)
文摘Conophylline, is a bis (indole) alkaloid consisting of two pentacyclic aspidosperma skeletons, isolated from Tabernaemontana divaricata, which has been found to induce β-cell differentiation in rat pancreatic acinar carcinoma cells and in cultured rat pancreatic tissue. However, the precise role of conophylline in the growth and survival of immortalized pancreatic mesenchymal stem cells (iPMSCs) derived from fetal porcine pancreas were not understood at present. To determine whether this molecule is involved in controlling the proliferation of iPMSCs, we examined the effects of conophylline on iPMSCs. We found that conophylline can robustly stimulate iPMSCs proliferation, even promote their potential differentiation into islet-like clusters analyzed by cell counting, morphology, RT-PCR and real-time PCR, Western blotting, glucose-stimulated insulin release and insulin content analysis. The effects of conophylline were inhibited by LY294002, which is the inhibitor of the PI3K pathway. These results suggest that conophylline plays a key role in the regulation of cell mass proliferation, maintenance of the undifferentiated state of iPMSCs and also promotes iPMSCs differentiated into insulin-producing cells.
基金Supported by National 863 Program of China,No.2004AA227070
文摘AIM: To reserve the rare Chinese familial adenomas polyp (FAP) family resource and to investigate the clinical features of FAP in Chinese for its diagnosis. METHODS: Clinical features of patients with FAP were investigated. If there is any question, their medical records were verified. Blood sample was taken and lymphocyte immortal cell lines were established with modified EB-transformation methods. Congenital hypertrophy of retinal pigment epithelium (CHRPE) was checked by an experienced ophthalmologist. RESULTS: Twenty seven families including 21 classical FAP (CFAP) families, 3 attenuated FAP (AFAP) families, and 3 suspected AFAP families were investigated. A total of 116 lymphocyte immortal cell lines were established from 26 families. In all the FAP families, colorectal cancer occurred at the mean age of 42.84 years. Of the 16 families checked, 15 (93.75%) had CHRPE. The mean number of patients suffering from colorectal neoplasm was 3.14 in CFAP families and 2.0 in AFAP families (P 〈 0.01). The mean oldest age at diagnosis of FAP was 41.75 years in CFAP families, and 58.67 years in AFAP families, respectively (P 〈 0.01). Mean age of development of colorectal cancer was 42.23 in CFAP and 57.33 years old in AFAP (P 〈 0.01). Mean of the earliest age at diagnosis of FAP was 29.95 years in the FAP families with a positive family history and 46.80 years in the FAP families with a negative family history (P 〈 0.01). The ratio of extra-intestinal tumors to colorectal neoplasms was different in the two kinds of families with positive and negative family history (P 〈 0.01). CONCLUSION: Additional use of ciclosporin will effectively improve to establish lymphocyte immortal cell lines with modified EB- transformation methods. In Chinese FAP, there was a high frequency of CHRPE, and a later age at diagnosis and a later age of development of colorectal cancer in AFAR And earlier age at diagnosis in FAP with positive family history was also found that will help to diagnose various kinds of FAP in Chinese.