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1.
Leukemia ; 24(4): 748-55, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20130600

RESUMO

Myelodysplastic syndromes (MDS) are a group of hematopoietic stem cell disorders characterized by refractory cytopenias and susceptibility to leukemic transformation. On a subset of MDS patients with deletion of the long arm of chromosome 5 (del(5q)), lenalidomide exerts hematological and cytogenetic effects, but the underlying pharmacological mechanisms are not fully understood. In this study, we have investigated the in vitro effects of lenalidomide on an MDS-derived cell line, MDS-L, which carries del(5q) and complex chromosome abnormalities. We found that the growth of MDS-L cells was specifically suppressed mainly by apoptosis, and in addition, multinucleated cells were frequently formed and finally died out in the presence of lenalidomide. Time-lapse microscopic observation and the DNA ploidy analysis revealed that lenalidomide does not affect DNA synthesis but inhibits cytokinesis of MDS-L cells. The gene expression profile showed decreased expression of M phase-related genes such as non-muscle myosin heavy-chain 10, polo-like kinase 1, aurora kinase B, citron kinase and kinesin family member 20A(KIF20A). Interestingly, KIF20A is located at 5q31. These data contribute to the understanding of action mechanisms of lenalidomide on MDS with del(5q) and complex abnormalities.


Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Deleção Cromossômica , Cromossomos Humanos Par 5/genética , Citocinese/efeitos dos fármacos , Síndromes Mielodisplásicas/patologia , Talidomida/análogos & derivados , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Western Blotting , Divisão Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Imunofluorescência , Perfilação da Expressão Gênica , Humanos , Cariotipagem , Lenalidomida , Síndromes Mielodisplásicas/tratamento farmacológico , Síndromes Mielodisplásicas/genética , Análise de Sequência com Séries de Oligonucleotídeos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Talidomida/farmacologia , Células Tumorais Cultivadas
2.
Reprod Domest Anim ; 43(3): 323-327, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18069946

RESUMO

A limited number of reports is available on cryopreservation of in vitro fertilization (IVF)-derived cat blastocysts. In the present study, IVF-derived domestic cat embryos which reached the blastocyst stage either on day 6 or day 7 were cryopreserved by vitrification using Cryotop as a cryodevice. Fresh control and post-warm surviving blastocysts were examined by differential cell staining with Hoechst 33342 and propidium iodide to determine total cell number and inner cell mass (ICM) ratio, and the post-warm survival rate was determined by re-expansion of the blastocoel during 24 h of in vitro culture. In fresh control, the mean number of total cells of day 7 blastocysts (61.4 cells) tended to be smaller than that of day 6 blastocysts (81.9 cells, p = 0.096). The post-warm survival rates of day 6 and day 7 blastocysts were not statistically different (73.8%; 31 of 42 vs 66.7%; 18 of 27). There were no significant differences in the total cell number and ICM ratio between fresh control and vitrified blastocysts, although the ICM ratio of surviving day 7 blastocysts was significantly smaller than that of fresh controls (stained at day 8, 18.9% vs 28.9%, p < 0.05). These results indicate that IVF-derived domestic cat embryos that reached the blastocyst stage earlier can survive the Cryotop vitrification without a reduction in the parameters studied.


Assuntos
Blastocisto/fisiologia , Gatos/embriologia , Criopreservação/veterinária , Técnicas de Cultura Embrionária/veterinária , Desenvolvimento Embrionário/fisiologia , Fertilização in vitro/veterinária , Animais , Contagem de Células/veterinária , Sobrevivência Celular , Criopreservação/métodos , Técnicas de Cultura Embrionária/métodos , Embrião de Mamíferos/fisiologia , Feminino , Cinética
3.
Br J Haematol ; 127(3): 292-8, 2004 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15491288

RESUMO

The neuron cytoplasmic protein gene product 9.5 (PGP9.5)/ubiquitin-C-terminal hydrolase 1 (UCHL-1) protein is a thiol protease that recognizes and hydrolyzes a peptide bond at the C-terminal of ubiquitin, and is involved in the processing of ubiquitin precursors and ubiquinated proteins. Although this molecule is known as a specific tissue marker for the neuroendocrine system, many reports have indicated that PGP9.5 is a marker for certain tumour types, such as cancer of the lung, colon, and pancreas. The expression of PGP9.5 in myeloma cells was examined. PGP9.5 seemed to be expressed specifically in myeloma cells as compared with other haematological malignant cells. In addition, in myeloma cells subjected to growth-factor starvation, the upregulation of PGP9.5 was observed in association with that of p27(Kip1), a cyclin-dependent-kinase inhibitor, although the upregulation caused by irradiation was milder. In contrast, the hypoxic culture of myeloma cells induced down-regulation of PGP9.5. These results suggested that PGP9.5 may be a good marker for myeloma among haematological malignancies. In addition, it may indicate certain cellular features of myeloma cells, such as sensitivity to proteasome inhibitors.


Assuntos
Biomarcadores Tumorais/análise , Mieloma Múltiplo/química , Ubiquitina Tiolesterase/análise , Western Blotting/métodos , Hipóxia Celular , Linhagem Celular Tumoral , Raios gama , Humanos , Imuno-Histoquímica/métodos , RNA Mensageiro/análise , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Ubiquitina Tiolesterase/genética
4.
Clin Chem ; 45(12): 2158-63, 1999 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10585348

RESUMO

BACKGROUND: Various methods are available to measure serum cholesterol concentrations. Of these, the cholesterol ester hydrolase (CEH)-cholesterol oxidase-peroxidase chromogenic method is widely used. However, this method has the disadvantage of interference by reducing substances. We developed and evaluated an endpoint assay for serum cholesterol, based on a CEH-cholesterol dehydrogenase (CDH)-ultraviolet method. METHODS: Cholesterol esters are first hydrolyzed to free cholesterol by CEH. The free cholesterol is then reduced by CDH to cholest-4-ene-3-one with the simultaneous production of beta-NADH from beta-NAD(+). At equilibrium, the CDH reaction gives incomplete conversion of cholesterol to cholest-4-ene-3-one. To overcome this disadvantage, we added hydrazine monohydrate to the reaction mixture to remove cholest-4-ene-3-one, which allowed the reaction to proceed to completion and gave stoichiometric production of beta-NADH from the reaction of beta-NAD(+) with cholesterol. RESULTS: We tested whether the amount of cholesterol added was equivalent to the absorbance change of NADH at 340 nm with six aqueous samples. Recoveries were 97.1-100.3%. The reaction was linear up to 20.28 mmol/L. The mean within-day (n = 20) and between-day (n = 10) imprecision (CV) was 0. 29-0.43% and 0.22-0.61%, respectively. No interference by bilirubin, hemoglobin, ascorbic acid, and other reducing agents was observed. The equation obtained in comparison with the modified Abell-Levy-Brodie-Kendall method was: y = 0.992x - 0.0058 mmol/L; r = 0.997; S(y|x) = 0.117 mmol/L; n = 50. CONCLUSION: This method is an accurate, reliable method for serum cholesterol analysis and is amenable to automation.


Assuntos
Colesterol/sangue , Colorimetria/métodos , Oxirredutases/química , Colesterol/química , Humanos , Hidrazinas/química , Concentração de Íons de Hidrogênio , NAD/química , Espectrofotometria Ultravioleta
5.
Appl Opt ; 38(23): 5066-72, 1999 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-18323999

RESUMO

The signal-to-noise ratio (SNR) on the fluorescence readout of a near-field photochromic memory was theoretically studied. Under various conditions the shot-noise-limited SNR was analyzed. SNR by bright spot recording (BSR) that was better than that by dark spot recording (DSR) was obtained under the condition of low writing power or wide bandwidth. Under the condition of bandwidth W = 1 MHz and P(write) = 10(-8) W only BSR can attain sufficiently high SNR, and the SNR was greater by as much as 30 dB than that of DSR. It was concluded that BSR is a promising method for high-density near-field photochromic memory with a fluorescence readout.

6.
Appl Opt ; 37(20): 4419-24, 1998 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-18285892

RESUMO

The fluorescence- and transmittance-detection readout methods of a near-field photochromic optical memory by a scanning-probe technique were studied theoretically. Shot noise, as the principal noise, was taken into account in an analysis of the signal-to-noise ratio (SNR). Under most conditions, fluorescence-detection readout yielded a better SNR than did transmittance-detection readout. For a transmittance change of 0.9-1.0 as a result of recording, a readout light power of approximately 100 nW, and a system bandwidth of 1 MHz, only the fluorescence-detection readout method, under the condition that the fluorescent layer of the medium have a fluorescence quantum yield greater than 0.4, can produce a sufficiently large SNR.

7.
Res Vet Sci ; 52(1): 105-9, 1992 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-1553428

RESUMO

Progesterone, oestrone and oestradiol-17 beta levels in the muscle, fat, liver, kidney and plasma of steers treated with Synovex S, untreated steers, and cows during the normal oestrous cycle, were examined. Progesterone levels in female tissues reached a maximum in the luteal phase and fell to a minimum in the follicular phase. Oestrogen levels (oestrone and oestradiol-17 beta) did not change during the cycle. Progesterone and oestrogen levels in the tissues of steers treated with Synovex S and untreated steers were not statistically different. Tissue progesterone levels in steers were much lower than those in cows during the luteal phase. The highest oestrogen levels were found in the fat of female animals. These results indicate that residue levels of progesterone and oestrogen in the muscle and fat of steers treated with Synovex S were within the physiological range, and lower than those of cows.


Assuntos
Bovinos/metabolismo , Resíduos de Drogas/análise , Estradiol/análise , Estrona/análise , Progesterona/análise , Tecido Adiposo/química , Tecido Adiposo/metabolismo , Animais , Estradiol/sangue , Estradiol/farmacocinética , Estrona/sangue , Estro/metabolismo , Feminino , Fase Folicular/fisiologia , Rim/química , Rim/metabolismo , Fígado/química , Fígado/metabolismo , Fase Luteal/fisiologia , Masculino , Músculos/química , Músculos/metabolismo , Progesterona/sangue , Progesterona/farmacocinética , Distribuição Tecidual
8.
Diagn Cytopathol ; 4(3): 234-8, 1988.
Artigo em Inglês | MEDLINE | ID: mdl-2474417

RESUMO

A case of ovarian serous adenocarcinoma presenting with ascitic fluid is reported. Cytology of the ascitic fluid showed the presence of cilia on most of malignant tumor cells. These tumor cells occurred singly; cilia usually appeared in unipolar locations. Immunocytochemical studies were performed on the ascitic fluid samples as well as tissue sections. CA19-9, CA125, CA50, and epithelial antigens were positive, while carcinoembryonic antigen was negative. The positive reactions were characteristic for cilia of the tumor cells. The findings also emphasize that positive reaction of these markers will usually exclude a noncommon epithelial tumor, but will not distinguish between benign and malignant ovarian tumors. Report of cilia-bearing tumor cells in ascitic fluid are few; no one, to the best of our knowledge, has previously documented the immunocytochemistry of these tumor cells.


Assuntos
Adenocarcinoma/patologia , Líquido Ascítico/patologia , Neoplasias Ovarianas/patologia , Adenocarcinoma/imunologia , Adulto , Antígenos de Neoplasias/análise , Antígenos Glicosídicos Associados a Tumores/análise , Antígeno Carcinoembrionário/análise , Núcleo Celular/patologia , Cílios/patologia , Citoplasma/patologia , Feminino , Histocitoquímica , Humanos , Glicoproteínas de Membrana/análise , Mucina-1 , Neoplasias Ovarianas/imunologia , Coloração e Rotulagem
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