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61.
Grace X. Ma Steve Shive Yin Tan Wanzhen Gao Joanne Rhee Micah Park Jaesool Kim Jamil I. Toubbeh 《Cancer epidemiology》2009,33(5):381-386
Background: Despite evidence of a decline in both incidence and prevalence of colorectal cancer nationwide, it remains the second most commonly diagnosed cancer and the third highest cause of mortality among Asian Americans, including Korean Americans. This community-based and theoretically guided study evaluated a culturally appropriate intervention program that included a bilingual cancer educational program among Korean Americans including information on CRC risks, counseling to address psychosocial and access barriers, and patient navigation assistance. Methods: A two-group quasi-experimental design with baseline and post-intervention assessment and a 12-month follow-up on screening was used in the study. Korean Americans (N = 167) were enrolled from six Korean churches. The intervention group received culturally appropriate intervention program addressing accessibility and psychosocial barriers, and navigation assistance for screening. The control group received general health education that included cancer-related health issues and screening. Results: There was a significant difference (p < 0.05) between the post-intervention and control groups in awareness of CRC risk factors. There was also a significant improvement in the pre–post across HBM measures in the intervention group for perceived susceptibility (p < 0.05) and benefits and barriers to screening (p < 0.001). At baseline, 13% of participants in the intervention group and 10% in control group reported having had a CRC cancer screening test in the previous year. At the 12-month post-intervention follow-up, 77.4% of participants in the intervention group had obtained screening compared to 10.8% in the control group. Conclusion: While health disparities result from numerous factors, a culturally appropriate and church-based intervention can be highly effective in increasing knowledge of and access to, and in reducing barriers to CRC screening among underserved Koreans. 相似文献
62.
Some β-d-hexopyranosides of 1-thio-d-glucose, 2-acetamido-2-deoxy-1-thio-d-glucose, and 1-thio-d-galactose were examined by laser-Raman spectroscopy. An anomeric CH bending vibration was found at 891 ± 7 cm-1 for all compounds investigated; thus, the anomers of these sugars can be differentiated by Raman spectroscopy. The N-acetyl group and carboxyl group can also be detected by Raman spectroscopy. Unlike protein samples, the carbohydrates in aqueous solution yield less useful information from Raman spectra than in the solid state; this is due to the extensive overlapping of carbohydrate OH bands with water OH bands. 相似文献
63.
Chung-Feng Hwang Li-Yen Shiu Li-Jen Su Yu-Fang Yin Wei-Sheng Wang Shun-Chen Huang Tai-Jan Chiu Chao-Cheng Huang Yen-Yi Zhen Hsin-Ting Tsai Fu-Min Fang Tai-Lin Huang Chang-Han Chen 《PloS one》2013,8(12)
Background
Nasopharyngeal carcinoma (NPC) is known for its high metastatic potential and locoregional recurrence, although the molecular alterations that are driving NPC metastasis remain unclear at this time. This study aimed to examine the expression of fibulin-5 in NPC, correlate the results with clinicopathological variables and survival, and to investigate the role of fibulin-5 in human NPC cell lines.Material and Methods
Standard semi-quantitative-RT-PCR, quantitative-RT-PCR, immunoblotting, and immunohistochemistry were used to investigate the mRNA and protein expression profiles of fibulin-5 in normal and NPC tissues. Immunohistochemistry of fibulin-5 was correlated with clinicopathological characteristics by univariate analyses. NPC cells overexpressing fibulin-5 or fibulin-5-siRNA cells were generated by stable transfection to characterize the molecular mechanisms of fibulin-5-elicited cell growth and metastasis.Results
Our results demonstrated that fibulin-5 overexpression in NPC specimens and significantly correlated with advanced tumor metastasis indicating a poor 5-year overall survival. Fibulin-5 was mainly expressed in the nucleus in human NPC specimens and cell lines. Functionally, fibulin-5 overexpression yielded fast growth in NPC cells. In addition, fibulin-5 promotes cell metastasis in NPC cells through increased FLJ10540 and phosphor-AKT activity. In contrast, siRNA depletion of fibulin-5 suppressed FLJ10540 expression and phosphor-AKT activity. Suppression of either fibulin-5 or FLJ10540 can cause significant inhibition with regards to cell motility in NPC cells. Finally, immunohistochemical analysis of human aggressive NPC specimens showed a significant and positive correlation between fibulin-5 and FLJ10540 expression.Conclusion
Higher fibulin-5 expression is not only an important indicator of poor survival, but also contributes to the development of new therapeutic strategies in the FLJ10540/AKT pathway for NPC treatment. 相似文献64.
Wang SF Si YX Wang ZJ Yin SJ Yang JM Qian GY 《International journal of biological macromolecules》2012,50(4):981-990
A folding study of creatine kinase from Pelodiscus sinensis has not yet been reported. To gain more insight into structural and folding mechanisms of P. sinensis CK (PSCK), denaturants such as SDS, guanidine HCl, and urea were applied in this study. We purified PSCK from the muscle of P. sinensis and conducted inhibition kinetics with structural unfolding studies under various conditions. The results revealed that PSCK was completely inactivated at 1.8 mM SDS, 1.05 M guanidine HCl, and 7.5 M urea. The kinetics via time-interval measurements showed that the inactivation by SDS, guanidine HCl, and urea were all first-order reactions with kinetic processes shifting from monophase to biphase at increasing concentrations. With respect to tertiary structural changes, PSCK was unfolded in different ways; SDS increased the hydrophobicity but retained the most tertiary structural conformation, while guanidine HCl and urea induced conspicuous changes in tertiary structures and initiated kinetic unfolding mechanisms. Our study provides information regarding PSCK and enhances our knowledge of the reptile-derived enzyme folding. 相似文献
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68.
Fragile X syndrome (FX), the most common heritable cause of mental retardation and autism, is a developmental disorder characterized by physical, cognitive, and behavioral deficits. FX results from a trinucleotide expansion mutation in the fmr1 gene that reduces levels of fragile X mental retardation protein (FMRP). Although research efforts have focused on FMRP's impact on mGluR signaling, how the loss of FMRP leads to the individual symptoms of FX is not known. Previous studies on human FX blood cells revealed alterations in the cyclic adenosine 3', 5'-monophosphate (cAMP) cascade. We tested the hypothesis that cAMP signaling is altered in the FX nervous system using three different model systems. Induced levels of cAMP in platelets and in brains of fmr1 knockout mice are substantially reduced. Cyclic AMP induction is also significantly reduced in human FX neural cells. Furthermore, cAMP production is decreased in the heads of FX Drosophila and this defect can be rescued by reintroduction of the dfmr gene. Our results indicate that a robust defect in cAMP production in FX is conserved across species and suggest that cAMP metabolism may serve as a useful biomarker in the human disease population. Reduced cAMP induction has implications for the underlying causes of FX and autism spectrum disorders. Pharmacological agents known to modulate the cAMP cascade may be therapeutic in FX patients and can be tested in these models, thus supplementing current efforts centered on mGluR signaling. 相似文献
69.
Yuan Jiang 《Developmental biology》2009,334(2):535-2384
The TALE homeodomain-containing PBC and MEIS proteins play multiple roles during metazoan development. Mutations in these proteins can cause various disorders, including cancer. In this study, we examined the roles of MEIS proteins in mesoderm development in C. elegans using the postembryonic mesodermal M lineage as a model system. We found that the MEIS protein UNC-62 plays essential roles in regulating cell fate specification and differentiation in the M lineage. Furthermore, UNC-62 appears to function together with the PBC protein CEH-20 in regulating these processes. Both unc-62 and ceh-20 have overlapping expression patterns within and outside of the M lineage, and they share physical and regulatory interactions. In particular, we found that ceh-20 is genetically required for the promoter activity of unc-62, providing evidence for another layer of regulatory interactions between MEIS and PBC proteins. 相似文献
70.
Multiple evidence shows that metformin serves as a potential agent for Colorectal Cancer (CRC) treatment, while its molecular mechanisms still require detailed investigation. Here, we revealed that metformin specifically suppressed the proliferation of CRC cells by causing G1/S arrest, and INHBA is a potential target for metformin to play an anti-proliferation effect in CRC. We verified the oncogene role of INHBA by knocking down and overexpressing INHBA in CRC cells. Silencing INHBA abrogated the cell growth, while overexpression INHBA promotes the proliferation of CRC cells. As an oncogene, INHBA was aberrant overexpression in CRC tissues and closely related to the poor prognosis of CRC patients. In mechanism, INHBA is an important ligand of TGF-β signaling and metformin blocked the activation of TGF-β signaling by targeting INHBA, and then down-regulated the activity of PI3K/Akt pathway, leading to the reduction of cyclinD1 and cell cycle arrest. Together, these findings indicate that metformin down-regulates the expression of INHBA, then attenuating TGF-β/PI3K/Akt signaling transduction, thus inhibiting the proliferation of CRC. Our study elucidated a novel molecular mechanism for the anti-proliferation effect of metformin, providing a theoretical basis for the application of metformin in CRC therapy.Subject terms: Colorectal cancer, Cell growth, Target identification 相似文献