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241.

Background

Drug response variability observed amongst patients is caused by the interaction of both genetic and non-genetic factors, and frequencies of functional genetic variants are known to vary amongst populations. Pharmacogenomic research has the potential to help with individualized treatments. We have not found any pharmacogenomics information regarding Uygur ethnic group in northwest China. In the present study, we genotyped 85 very important pharmacogenetic (VIP) variants (selected from the PharmGKB database) in the Uygur population and compared our data with other eleven populations from the HapMap data set.

Results

Through statistical analysis, we found that CYP3A5 rs776746, VKORC1 rs9934438, and VKORC1 rs7294 were most different in Uygur compared with most of the eleven populations from the HapMap data set. Compared with East Asia populations, allele A of rs776746 is less frequent and allele A of rs7294 is more frequent in the Uygur population. The analysis of F-statistics (Fst) and population structure shows that the genetic background of Uygur is relatively close to that of MEX.

Conclusions

Our results show significant differences amongst Chinese populations that will help clinicians triage patients for better individualized treatments.
  相似文献   
242.
Helicobacter pylori is a major human pathogen associated with gastric diseases such as chronic active gastritis, peptic ulcer, and gastric carcinoma. The growth factor progranulin (PGRN) is a secreted glycoprotein that functions as an important regulator of cell growth, migration, and transformation. We aimed to determine the molecular mechanisms by which H. pylori upregulates the expression of PGRN and the relationship between H. pylori infection and production of PGRN in controlling cell proliferation and migration. Levels of PGRN were examined in gastric tissues from patients and in vitro in gastric epithelial cells. Cell proliferation was measured by colony formation assay. Cell migration was monitored by wound healing migration assay. PGRN protein levels were increased in patients with gastritis and gastric cancer tissue. Infection of gastric epithelial cells with H. pylori significantly increased PGRN expression in a time-dependent manner. Blockade of the p38 and MEK1/2 pathway by inhibitor inhibited H. pylori-mediated PGRN upregulation. Activation of p38 and MEK1/2 pathway by H. pylori was also identified. Knockdown of PGRN attenuated the H. pylori-induced proliferative activity and migration of cancer cells. These findings suggest that the upregulation of PGRN in H. pylori-infected gastric epithelial cells may contribute to the carcinogenic process.  相似文献   
243.
A lateral flow biosensor based on an immuno-chromatographic assay has been developed for the detection of DNA-binding proteins. The biosensor is composed of four parts: a sample pad, a conjugate pad, a strip of nitrocellulose membrane and an absorbent pad. A DNA probe containing a specific protein binding consensus sequence is coated onto gold nanoparticles, while an antibody against the DNA-binding protein is immobilized onto a test zone of the nitrocellulose membrane. The target protein binds to the protein binding DNA sequence that is coated on the gold nanoparticles to form nanoparticle-DNA-protein complexes, and the complexes are then captured by the antibody immobilized on the test zone to form a red line for visual detection of the target protein. This biosensor was successfully applied to a DNA-binding protein, c-jun, and the developed biosensor allows for the rapid detection of down to 0.2 footprint unit of c-jun protein within 10 min. This biosensor was verified using HeLa cells and it visually detected c-jun activity in 100 μg of crude cell lysate protein. The antibody against c-jun used in the biosensor can distinguish c-jun from other nonspecific proteins, with high specificity.  相似文献   
244.
Li J  Dai G  Cheng YB  Qi X  Geng MY 《Glycobiology》2011,21(8):1010-1018
Polysialic acid (PSA), a carbohydrate polymer mainly present in the neural cell adhesion molecule (NCAM), promotes neural plasticity; however, its mode of action in tumor malignancy remains largely unknown. In this study, we investigated the influence of polysialylation on cell migration. PSA consistently promoted cell migration on different extracellular matrices (ECMs) but differentially affected cell adhesion. All of these actions were reversed by endo-N-acetylneuraminidase treatment, and PSA-driven migration was inhibited by the specific fibroblast growth factor receptor (FGFR) inhibitor Su5402. Consistent with this latter observation, PSA-stimulated migration on different ECMs was paralleled by activation of the FGFR and its downstream signaling components, PLC-γ, focal adhesion kinase and extracellular signal-regulated kinase 1/2. In contrast, the pattern of p59(fyn) activation correlated with differential adhesion to different ECMs. Collectively, these results indicate that PSA-conjugated NCAM potentiates signal transduction by the FGFR pathway and thereby enhances cell migration independent of adhesion capability, providing additional insights into the role of PSA in cancer development.  相似文献   
245.
Peng J  Su Y  Shi Q  Chen W  Jiang Z 《Bioresource technology》2011,102(3):2289-2295
A mild and facile grafting of poly(ether glycol) methyl ether methacrylate (PEGMA) monomers onto polyethersulfone (PES) was carried out. Then, the PES-g-PEGMA membranes with integrally anisotropic morphology were fabricated through the coupling of non-solvent induced phase inversion and surface segregation. Compared with PES control membrane, the surface hydrophilicity of PES-g-PEGMA membranes was remarkably enhanced due to the drastic enrichment of poly(ethylene glycol) (PEG) segments on the membrane surface; protein adsorption was significantly inhibited due to the hydrogen bonding interactions between hydrophilic groups and water molecules. Ultrafiltration experiments were used to assess the permeability and protein fouling resistance of the PES-g-PEGMA membranes. It was found that the PES-g-PEGMA membranes with higher surface coverage of PEG segments displayed stronger antibiofouling property. Moreover, the stable antibiofouling property for PES-g-PEGMA membranes was acquired due to covalent bonding interactions between hydrophilic PEGMA side chains and PES main chains.  相似文献   
246.
An SAR survey at the C-6 benzoxazinone position of a novel scaffold which inhibits bacterial type IIa topoisomerase demonstrates that a range of small electron donating groups (EDG) and electron withdrawing groups (EWG) are tolerated for antibacterial activity. Cyano was identified as a preferred substituent that affords good antibacterial potency while minimizing hERG cardiac channel activity.  相似文献   
247.
A series of ethyl 3-aryl-4-oxo-3,3a,4,6-tetrahydro-1H-furo[3,4-c]pyran-3a-carboxylates were prepared through the metal-catalyzed domino reaction of alkylidene malonates and 1,4-butynediol under a one-pot reaction condition at room temperature. Their in vitro anti-proliferative activities were subsequently evaluated in A549, QGY and HeLa cells. The majority of the compounds showed potent anti-tumor activity against HeLa cells. In particular, compound 3l was the most potent compound with IC50 value of 5.4 μM. For the first time, the X-ray structure of the anti-tumor ethyl 3-aryl-4-oxo-3,3a,4,6-tetrahydro-1H-furo[3,4-c]pyran-3a-carboxylates is determined.  相似文献   
248.
Zhou WJ  Geng ZH  Chi S  Zhang W  Niu XF  Lan SJ  Ma L  Yang X  Wang LJ  Ding YQ  Geng JG 《Cell research》2011,21(4):609-626
The Slit family of guidance cues binds to Roundabout (Robo) receptors and modulates cell migration. We report here that ectopic expression of Slit2 and Robo1 or recombinant Slit2 treatment of Robo1-expressing colorectal epithelial carcinoma cells recruited an ubiquitin ligase Hakai for E-cadherin (E-cad) ubiquitination and lysosomal degradation, epithelial-mesenchymal transition (EMT), and tumor growth and liver metastasis, which were rescued by knockdown of Hakai. In contrast, knockdown of endogenous Robo1 or specific blockade of Slit2 binding to Robo1 prevented E-cad degradation and reversed EMT, resulting in diminished tumor growth and liver metastasis. Ectopic expression of Robo1 also triggered a malignant transformation in Slit2-positive human embryonic kidney 293 cells. Importantly, the expression of Slit2 and Robo1 was significantly associated with an increased metastatic risk and poorer overall survival in colorectal carcinoma patients. We conclude that engagement of Robo1 by Slit2 induces malignant transformation through Hakai-mediated E-cad ubiquitination and lysosomal degradation during colorectal epithelial cell carcinogenesis.  相似文献   
249.
目的:通过对小剂量多次链脲佐菌素(multiple low doses of streptozotocin MLD-STZ)诱导的1型糖尿病模型小鼠胰腺与正常小鼠胰腺蛋白的比较分析,拟从蛋白水平上对1型糖尿病发病机制进行探讨。方法:将20只雄性昆明鼠,按体重随机分为MLD-STE模型组和正常对照组(n=10),应用二维凝胶电泳技术获得胰腺的二维电泳图谱,经ImageMaster2D 5.0软件分析获得差异蛋白,结合质谱(MALDI-TOF-MS)与MASCOT网络数据库进行匹配鉴定蛋白。结果:与正常对照组比较,模型组胰腺中有23个蛋白表达改变,其中15个蛋白表达下调,8个蛋白表达上调。经肽质量指纹图谱分析及蛋白数据库检索,最终鉴定出15个差异蛋白,根据其功能可分为:①代谢相关蛋白;②氧化应激相关蛋白;③催化酶类;④细胞骨架蛋白;⑤伴侣蛋白;⑥免疫相关蛋白;⑦其他蛋白。结论:研究结果表明模型组胰腺蛋白表达存在明显改变,提示1型糖尿病的发生是多途径多靶点的共同作用,同时这些改变蛋白为研究和治疗糖尿病等相关疾病提供了新靶标。  相似文献   
250.
杜鹃花属植物扦插繁殖研究进展   总被引:3,自引:0,他引:3  
我国有着丰富的杜鹃花资源,但有关其繁殖应用的研究还具有一定的局限。种子育苗耗时长,组培育苗成本和技术要求高,都不适于杜鹃花属植物的大面积生产。扦插繁殖快,还可保持母本的优良性状。从插条的选择,准备,插条的生根激素处理,扦插基质的选择,外界环境条件对扦插成活率的影响及扦插后的养护管理等六个方面对杜鹃的扦插繁殖技术的研究进行综述,以期推进杜鹃花属植物,尤其是中国野生杜鹃的引种驯化和大面积的推广应用。  相似文献   
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