746 resultados para Bcl-X1


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Purpose: To investigate the antitumor activity of physcion8-O-β-glucopyranoside (PSG) against cervical cancer, as well as its mechanisms. Methods: The anti-proliferative effects of PSG on HeLa cells were determined by CCK-8 assay and the half maximal inhibitory concentration (IC50) values were calculated. Subsequently, a mouse xenograft model of HeLa cell line was established to investigate the antitumor effect of PSG in vivo. Furthermore, cell apoptosis was investigated by fluorescence microscopy via DAPI staining, and other mechanisms were determined by Western blot assay. Results: In vitro, PSG exhibited significant anti-proliferative effect on HeLa cells (p <0.05) in concentration-and time-dependent manners, with an IC50 value of 41.34 μg/mL. In vivo, PSG also had significant anti-tumor activity in nude mouse xenograft model (p < 0.05), inhibiting tumor growth. Furthermore, the results showed that treatment with PSG (20, 40 and 60 μg/mL) for 24 h resulted in significantly increased apoptosis in HeLa cells (p < 0.05). Additionally, Western blot analysis revealed that after exposure to 20, 40 and 60 μg/mL of PSG for 24 h, protein expressions of C-caspase-3, Ccaspase-9 and Bax were markedly up-regulated (p < 0.05) while Bcl-2 was significantly down-regulated (p < 0.05). These results confirmed that PSG inhibited HeLa cell growth by inducing mitochondriamediated apoptosis via up-regulation of caspase-3 and caspase-9 and Bax, and down-regulation of Bcl2. Conclusion: The results demonstrate that PSG possesses notable anti-tumor activity against cervical cancer and that the mechanisms involve induction of apoptosis by mitochondria-mediated signaling pathway.

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Purpose: To optimize the extraction conditions of polysaccharides from Polygonum perfoliatum L. (PSDP) and to evaluate their anti-tumor activities on A549 cell line. Methods: Extraction of PSDP was optimized using Box-Behnken design (BBD). Three factors of response surface methodology (RSM) including extraction time, ratio of water to raw material and number of extractions were employed to optimize the yield of PSDP. The cytotoxic effect of PSDP on human lung carcinoma A549 cell line was evaluated in vivo, while its effects on expressions of caspase3, caspase-9, Bcl-2 and Bax were determined by western blot assay. Result: BBD was significant and applicable to PSDP extraction. Based on the contour plots, response surface plots and variance analysis, it predicted that the optimum conditions for PSDP extraction were: 1.58 h (extraction time); 30.18 mL/g (ratio of water to raw material); and 2.02 (number of extractions). PSDP had significant inhibitory effect on the growth of A549 cells in a concentration- and timedependent manner (p < 0.05). After treatment with PSDP, caspase-3, caspase-9 and Bax were significantly up-regulated (p < 0.05), whereas Bcl-2 was down-regulated, all concentration-dependently. Conclusion: RSM analysis is an appropriate method to optimize PSDP extraction. The results also indicate that PSDP has significant anti-tumor effect against A549 cells, most likely via inducing mitochondria-mediated apoptosis.

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Purpose: To determine the effect of phlomisoside F (PMF) on the proliferation, migration and invasion of human non-small cell lung cancer cell line A549 and explore the possible mechanisms. Methods: The anti-proliferative effect of PMF on A549 cells was determined by CCK-8. Subsequently, migration and invasion were evaluated by Transwell and Transwell with matrigel assays, respectively. Furthermore, cell cycle and apoptosis were assessed by flow cytometry, while the mechanisms of action were determined by Western blotting. Results: PMF exhibited significant anti-proliferative effect on A549 cells in concentration-dependent and time-dependent manners, with half maximal inhibitory concentration (IC50) of 54.51 μM. Treatment with PMF (10, 20 and 40 μM) for 48 h resulted in significantly decreased migration and invasion in A549 cells. In addition, PMF at concentrations of 25, 50 and 75 μM induced cell cycle arrest in G0/G1phase and enhanced cell apoptosis in A549 cells. Furthermore, caspase-3, caspase-9 and Bax protein expressions were up-regulated while Bacl-2 and COX-2 protein expressions were significantly downregulated at 10, 20 and 40 μM concentrations of PMF. Conclusion: PMF suppresses A549 cell growth, migration and invasion. The mechanism may be related to the induction of mitochondria-mediated apoptosis pathway via regulation of caspase-3, caspase-9, Bcl-2 and Bax expressions, and inhibition of PGE2 synthesis by reducing COX-2 expression.

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Purpose: To investigate the protective effect of rhamnopyranosyl vanilloyl (RV) from Scrophularia ningpoensis root against tetrachloromethane (CCl4)-induced acute liver injury (ALI) in mice. Methods: RV was isolated from S. ningpoensis by column chromatography. ALI model of mice was established by intraperitoneal injection of CCl4. Liver index, liver function indices, as well as serum alanine transaminase (ALT), aspartate aminotransferase (AST) and total bilirubin (TBIL) were evaluated. Lipid peroxidation (LPO)-related indices, including malonaldehyde (MDA), glutathione (GSH), superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px). Apoptotic proteins (Bcl-2, Bax and caspase-3) in liver tissue were determined by enzyme-linked immunosorbent assay (ELISA) and Western blot. Results: After treatment with RV (10, 20 or 40 mg/kg), liver index (5.65 - 5.21 vs. 6.68 %), ALT (90.18 - 79.68 vs. 112.47 U/L), AST (64.44 - 57.63 vs. 75.41 U/L) and TBIL (2.68 - 1.95 vs. 3.21 U/L) activities, as well as MDA (3.58 - 2.88 vs. 4.13 μmol/g), Bax and caspase-3 levels significantly (p < 0.05 or 0.01) decreased, compared with those in control group. After treatment with RV (10, 20 or 40 mg/kg), GSH (16.58 - 22.14 vs. 12.34 μmol/g), Bcl-2, SOD (86.45 - 107.61 vs. 68.43 U/mg) and GSH-Px (295.64 - 329.47 vs. 268.49 U/mg) levels or activities significantly (p < 0.05 or 0.01) increased, compared with those in control group. Conclusion: RV has protective effect against CCl4-induced ALI in mice, and the mechanisms involve the inhibition of LPO and apoptosis in liver cells. Thus, RV is a potential drug for the treatment of liver injury

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Purpose: To evaluate the effect of triptolide on the induction of cell apoptosis in human gastric cancer BGC-823 cells. Methods: The cytotoxicity of triptolide was evaluated by 3-(4, 5-dimethylthiazol-2-yl)-2, 5- diphenyltetrazolium bromide (MTT) assay. The effect of triptolide on cell proliferation was measured using lactate dehydrogenase (LDH) assay. Cell apoptosis was determined by Annexin V/propidium iodide (PI) double-staining assay. Results: MTT results indicate that triptolide significantly decreased cancer cell numbers in dose- and time-dependent manners in MTT assay. Data from LDH assay showed that triptolide markedly induced cytotoxicity in gastric cancer cells. Triptolide also remarkably induced both early and late apoptotic process in BGC-823 cells. In addition, the compound down-regulated the expression of anti-apoptotic Bcell lymphoma-2 (bcl-2) and up-regulated the expression of pro-apoptotic BCL-2-associated X (bax) in a dose-dependent manner. Furthermore, the pro-apoptotic activity of triptolide was involved in the activation of caspase-3 pathway in BGC-823 cells. Conclusion: Taken together, the findings strongly indicates that the pro-apoptotic activity of triptolide is regulated by caspase 3-dependent cascade pathway, and thus needs to be further developed for cancer therapy.

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In this study, a BCR-ABL expressing human chronic myelogenous leukaemia cell line (K562) was used to investigate the antitumoral potential of a novel lectin (CvL) purified from the marine sponge Cliona varians. CvL inhibited the growth of K562 cells with an IC50 value of 70 g/ml, but was ineffective to normal human peripheral blood lymphocytes in the same range of concentrations tested (180 g/ml). Cell death occurred after 72 h of exposure to the lectin and with sign of apoptosis as analysed by DAPI staining. Investigation of the possible effectors of this process showed that cell death occurred in the presence of Bcl-2 and Bax expression, and involved a caspase-independent pathway. Confocal fluorescence microscopy indicated a major role for the lysosomal protease cathepsin B in mediating cell death. Accordingly, pre-incubation of K562 cells with the cathepsin inhibitor L-trans-epoxysuccinyl-L-leucylamido-(4-guanidino)butane (E-64) abolished the cytotoxic effect of CvL. Furthermore, we found upregulation of tumor necrosis factor receptor 1 (TNFR1) and down-modulation of p65 subunit of nuclear factor kappa B (NFB) expression in CvL-treated cells. These effects were accompanied by increased levels of p21 and downmodulation of pRb, suggesting that CvL is capable of cell cycle arrest. Collectively, these findings suggest that cathepsin B acts as death mediator in CvL-induced cytotoxicity possibly in a still uncharacterized connection with the membrane death receptor pathway

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Mémoire numérisé par la Direction des bibliothèques de l'Université de Montréal.

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TET2 is a tumor suppressor gene that has been implicated in the epigenetic regulation of gene expression. Inactivating TET2 mutations are common in MDS. These mutations may contribute to early clonal dominance and myeloid transformation, although the exact mechanisms remain to be elucidated. Common to the environment of MDS are elevations in cytokines, such as TNFα and IFN-γ. It was hypothesized that inflammatory cytokines TNF-α and IFN-γ may promote clonal expansion of TET2 mutant progenitors. Adult (10-14 weeks-old) Tet2 wild type (+/+) and Tet2 mutant (-/-) C57BL/6 mice strains were chosen as a model system. Lineage negative cells (Lin-), enriched for hematopoietic stem and progenitor cells, were isolated from Tet2 +/+ and -/- bone marrow and cultured in the absence or presence of varying concentrations of TNFα or IFN-γ in methylcellulose colony formation assays and long term cell culture assays, over a period of 12 and 30 days respectively, and their colony growth, cell count, immunophenotype and resistance to apoptosis were examined. Where indicated, serial re-plating was performed. Expression of apoptotic regulators was assessed by qRT-PCR. In the triplicate experiments, starting with equal densities of Tet2 +/+ and -/- Lin- cells, Tet2 -/- Lin- cells displayed increased resistance to cytokine-induced growth suppression and superior colony forming ability over +/+ in the serial re-plating assays under stress of increasing TNFα or IFN γ. Tet2 -/- progenitors also displayed a lower apoptotic index compared to +/+ under stress of increasing TNFα, suggesting increased resistance to TNFα induced apoptosis. Transcriptional data showed low expression of Tnfr1, Fas and caspase 8, as well as a high expression of Bcl-2 and Iap1 in Tet2 -/- compared to +/+ under stress of TNFα. Tet2-/- also showed increased basal expression of endogenous TNFα mRNA compared to +/+. In the human colony growth assay, the clonal growth of TET2 mutant CFU-GM progenitors was enhanced at low TNFα concentrations. Conclusion: Mutations that promote resistance to environmental stem cell stressors are a known mechanism of clonal selection in aplastic anaemia and JAK2-mutant MPN and our findings suggest that this mechanism may be critical to clonal selection and dominance in MDS.

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A survey on smallholder dairy cow had conducted in Banyumas region from November 8th 1999 up to February 8th 2000. Forty six respondents were involved in this study (as samples). Cobb - Douglas analysis was applied in this survey. From the study can be concluded that a small holder owned 3.02 heads of dairy cow (2.2  ST), 1.44 heads of lactating cow with 9.77 L/day milk production on average. The benefit of the backyard farming was RP.70.603,225 per month on average. Feeding was the biggest influence on benefit because feed cost was 65.81 percent from the production cost. The milk production function , by the equation: Y = 0,8958 X1⁰·⁰³³² X2 0.049 X30.168 X40.608 The four variables can explain 92.4 percent (R²=0,924)on the milk  production variation .It can be suggested that to improve milk production on dairy cows can be done by intensifying labour, and improving the forage feeding. (Animal Production 3(1): 12-19 (2001)Key word: Milk  production ,production function and benefit

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The objective of research was to know the correlation between floor space and sanitation of cage with mastitis disease occurance on the dairy cattle. Sixtiy infected mastitis disease dairy cows were used in the research in the Banyumas regency. Survey was applied in this experiment and Linier Multiple Regression was used. The result showed that there were correlations between floor space  and sanitation of cage with mastitis which follow the regression line Yi = 15,355 + 1,087 X1 – 0,249 X2 (Animal Production 2(1): 9-12Key Words: mastitis, floor space, and sanitation

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An experiment entitled “Study on Estimation of Milk Production Based on Heart Girth Measurement and Udder Size of Fries Holland Dairy Cows “ has been carried at Karanglewas District Banyumas Regency. The objectives of this experiment were (1) to predict milk production of Fries Holland cows based on measurement of heart girth and udder size; (2) to complete information in attempting milk production estimation, especially Fries Holland cows; (3) to help the publics in case of productive cows selection. The material of this experiment was 40 heads of Fries Holland cows, at age of 3 years up to 5 years old. The result of this experiment (after the milk product data were corrected into 305 days lactation), showes that the average of heart girth was 180.20 ± 7.06 cm; udder size was 89.03 ± 23.35 dm2 and milk production was 2326.54 ± 331.79 litters. The data analysis indicated that correlation coefisient r = 0.87 and determination coefisient (R2) = 0,7651 and the multiple regression equation : Y = 1465.66 + 1.42 X1+ 6.79 X2. From the result of this experiment, if could be conclude that udder size parameter was the best variable of milk production estimation compared to heart girth and if can be used to estimated milk production. (Animal Production 4(1): 32-35 (2002)Key words : milk production, heart girth, udder size, fries holand