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1.
Stem Cells Dev ; 20(11): 1951-9, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21322785

RESUMO

Derivation of embryonic stem cells from patient-specific cloned blastocysts by somatic cell nuclear transfer (SCNT) holds promise for both regenerative medicine and cell-based drug discovery. However, the efficiency of blastocyst formation after human SCNT is very low. The developmental competence of SCNT embryos has been previously demonstrated in several species to be enhanced by treatment with histone deacetylase inhibitors, such as trichostatin A (TSA), to increase histone acetylation. In this study, we report that treatment of SCNT embryos with 5 nM TSA for 10 h following activation incubation increased the developmental competence of human SCNT embryos constructed from ß-thalassemia fibroblast cells. The efficiency of blastocyst formation from SCNT human embryos treated with TSA was approximately 2 times greater than that from untreated embryos. Cloned blastocysts were confirmed to be generated through SCNT by DNA and mitochondrial DNA fingerprinting analyses. Further, treatment of SCNT embryos with TSA improved the acetylation of histone H3 at lysine 9 in a manner similar to that observed in in vitro fertilized embryos.


Assuntos
Blastômeros/efeitos dos fármacos , Fibroblastos/efeitos dos fármacos , Inibidores de Histona Desacetilases/farmacologia , Ácidos Hidroxâmicos/farmacologia , Talassemia beta/patologia , Acetilação , Sequência de Bases , Blastocisto/patologia , Blastômeros/metabolismo , Forma Celular , Células Cultivadas , Clonagem de Organismos , Técnicas de Cocultura , DNA Mitocondrial/genética , Feminino , Fibroblastos/metabolismo , Histonas/metabolismo , Humanos , Cariótipo , Masculino , Repetições de Microssatélites , Dados de Sequência Molecular , Técnicas de Transferência Nuclear , Análise de Sequência de DNA , Injeções de Esperma Intracitoplásmicas
2.
J Genet Genomics ; 36(4): 229-39, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19376483

RESUMO

Poor quality embryos discarded from in vitro fertilization (IVF) laboratories are good sources for deriving human embryonic stem cell (hESC) lines. In this study, 166 poor quality embryos donated from IVF centers on day 3 were cultured in a blastocyst medium for 2 days, and 32 early blastocysts were further cultured in a blastocyst optimum culture medium for additional 2 days so that the inner cell masses (ICMs) could be identified and isolated easily. The ICMs of 17 blastocysts were isolated by a mechanical method, while those of the other 15 blastocysts were isolated by immunosurgery. All isolated ICMs were inoculated onto a feeder layer for subcultivation. The rates of ICM attachment, primary ICM colony formation and the efficiency of hESC derivation were similar between the ICMs isolated by the two methods (P>0.05). As a result, four new hESC lines were established. Three cell lines had normal karyotypes and one had an unbalanced Robertsonian translocation. All cell lines showed normal hESC characteristics and had the differentiation ability. In conclusion, we established a stable and effective method for hESC isolation and culture, and it was confirmed that the mechanical isolation was an effective method to isolate ICMs from poor embryos. These results further indicate that hESC lines can be derived from poor quality embryos discarded by IVF laboratories.


Assuntos
Massa Celular Interna do Blastocisto/citologia , Técnicas de Cultura de Células/métodos , Separação Celular/métodos , Células-Tronco Embrionárias/citologia , Diferenciação Celular , Linhagem Celular , Embrião de Mamíferos , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Humanos , Masculino
3.
Zhonghua Nan Ke Xue ; 15(1): 16-9, 2009 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-19288742

RESUMO

OBJECTIVE: To investigate the effect of sperm acrosin activity on the IVF-ET outcome. METHODS: We analyzed sperm parameters, morphology and acrosin activity for 909 infertile husbands by computer-assisted self-assessment (CASA), modified Papanicolaou staining and N-alpha-benzoyl-DL-arginine-p-nitroanilide (BAPNA), respectively, and detected the rates of fertilization, cleavage, quality embryos, embryo cryopreservation, implantation, clinical pregnancy and abortion. The wives were identified as normal or with mere oviduct problems. RESULTS: The rate of normal sperm morphology and sperm motility, vitality, rapid progressive velocity and concentration were significantly lower in the abnormal acrosin activity group than in the normal one (P < 0.01). Significant positive correlations were observed between acrosin activity and the above-mentioned semen parameters (P < 0.01). There were no significant differences in the number of retrieved eggs, the rates of cleavage, quality embryos, embryo cryopreservation, non-embryo transfer cycles and miscarriages, and the number of transferred embryos between the two groups (P > 0.05). The fertilization rate, the percentage of transfer cycles with only 1 embryo and the rate of implantation and clinical pregnancy were notably higher in the normal acrosin activity group than in the abnormal one (P < 0.01). CONCLUSION: Sperm acrosin activity is closely related with semen parameters, and it helps to predict the sperm fertilizing capacity and IVF-ET outcome.


Assuntos
Acrosina/metabolismo , Transferência Embrionária , Fertilização in vitro , Espermatozoides/enzimologia , Adulto , Feminino , Humanos , Infertilidade Masculina , Masculino , Gravidez , Taxa de Gravidez , Análise do Sêmen
4.
Hum Reprod ; 23(10): 2185-93, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18611919

RESUMO

BACKGROUND: Human embryonic stem cell (hESC) lines derived from poor quality embryos usually have either normal or abnormal karyotypes. However, it is still unclear whether their biological characteristics are similar. METHODS: Seven new hESC lines were established using discarded embryos. Five cell lines had normal karyotype, one was with an unbalanced Robertsonian translocation and one had a triploid karyotype. Their biological characteristics, short tandem repeat loci, HLA typing, differentiation capability and imprinted gene, DNA methylation and X chromosome inactivation status were compared between different cell lines. RESULTS: All seven hESC lines had similar biological characteristics regardless of karyotype (five normal and two abnormal), such as expression of stage-specific embryonic antigen (SSEA)-4, tumor-rejection antigen (TRA)-1-81 and TRA-1-60 proteins, transcription factor octamer binding protein 4 mRNA, no detectable expression of SSEA-1 protein and high levels of alkaline phosphatase activity. All cell lines were able to undergo differentiation. Imprinted gene expression and DNA methylation were also similar among these cell lines. Non-random X chromosome inactivation patterns were found in XX cell lines. CONCLUSIONS: The present results suggest that hESC lines with abnormal karyotype are also useful experimental materials for cell therapy, developmental biology and genetic research.


Assuntos
Linhagem Celular , Aberrações Cromossômicas , Células-Tronco Embrionárias/citologia , Diferenciação Celular , Metilação de DNA , Impressão Genômica , Teste de Histocompatibilidade , Humanos , Cariotipagem , Repetições de Microssatélites , Inativação do Cromossomo X
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