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991.
Priscilla F. McAuliffe Kurt W. Evans Argun Akcakanat Ken Chen Xiaofeng Zheng Hao Zhao Agda Karina Eterovic Takafumi Sangai Ashley M. Holder Chandeshwar Sharma Huiqin Chen Kim-Anh Do Emily Tarco Mihai Gagea Katherine A. Naff Aysegul Sahin Asha S. Multani Dalliah M. Black Elizabeth A. Mittendorf Isabelle Bedrosian Gordon B. Mills Ana Maria Gonzalez-Angulo Funda Meric-Bernstam 《PloS one》2016,11(3)
992.
Objective
General malnutrition usually occurs in critical limb ischemia (CLI) patients because of shortness of appetite and sleeplessness leaded by chronic pain. And amputation frequently is end-point of CLI patients. So the aim of this study was to assess the predictive ability of Geriatric nutritional risk index (GNRI) for predicting amputation in patients with CLI.Methods
A retrospective study was designed. Demographics, history, comorbidity, and risk factors for peripheral vascular disease of admitted patients, and laboratory study were documented. Patients’ height, weight and BMI were recorded. Amputation was identified as end-point during follow-up. Patients’ amputation-free survival (AFS) was recorded.Result
172 patients were identified, with mean age 71.98±3.12. Geriatric nutritional risk index (GNRI) = 90 was taken as cutoff value of high risk of amputation for CLI patients via using receiver operating characteristic (ROC) curve. Span of follow-up was 12–48 months. During follow-up, 60 patients (36.04%) received amputation surgery. And analyzed by Cox proportional hazards model, it is found that GNRI was the independent predictive factor for amputation in long term.Conclusion
This study revealed that GNRI was a reliable and effective predictive marker for AFS. GNRI could identify patients with high risk for amputation in early time. 相似文献993.
This fMRI study aimed to identify the neural mechanisms underlying the recognition of Chinese multi-character words by partialling out the confounding effect of reaction time (RT). For this purpose, a special type of nonword—transposable nonword—was created by reversing the character orders of real words. These nonwords were included in a lexical decision task along with regular (non-transposable) nonwords and real words. Through conjunction analysis on the contrasts of transposable nonwords versus regular nonwords and words versus regular nonwords, the confounding effect of RT was eliminated, and the regions involved in word recognition were reliably identified. The word-frequency effect was also examined in emerged regions to further assess their functional roles in word processing. Results showed significant conjunctional effect and positive word-frequency effect in the bilateral inferior parietal lobules and posterior cingulate cortex, whereas only conjunctional effect was found in the anterior cingulate cortex. The roles of these brain regions in recognition of Chinese multi-character words were discussed. 相似文献
994.
Caroline E. Sloan Marlise R. Luskin Anne M. Boccuti Alison R. Sehgal Jianhua Zhao Robert D. Daber Jennifer J. D. Morrissette Selina M. Luger Adam Bagg Phyllis A. Gimotty Martin Carroll 《PloS one》2016,11(4)
BackgroundAlthough cytogenetics-based prognostication systems are well described in acute myeloid leukemia (AML), overall survival (OS) remains highly variable within risk groups. An integrated genetic prognostic (IGP) model using cytogenetics plus mutations in nine genes was recently proposed for patients ≤60 years to improve classification. This model has not been validated in clinical practice.ConclusionsThe IGP model was not completely validated in our cohort. However, mutations in six out of the nine genes can be used to characterize survival (NPMI, IDH1, IDH2, FLT3-ITD, TET2, DNMT3A) and allow for more robust prognostication in the patients who are re-categorized by the IGP model. These mutations should be incorporated into clinical testing for younger patients outside of clinical trials, in order to guide therapy. 相似文献
995.
Pooja Dhupkar Huang Zhao Kalpana Mujoo Zhiqiang An Ningyan Zhang 《Biochemistry and Biophysics Reports》2016
Crk (C10 regulator of kinase) adaptor proteins are highly expressed in many types of human cancers and often contribute to aggressive cancer phenotypes. Crk II, a member of CRK family, has been reported to regulate cell migration and metastasis in breast cancer cells. However, its role in other cancer types has not been reported. In this study, we investigated the molecular function of Crk II in prostate cancer (PCa) cells (CWR-22rv1) in vitro and using a mouse tumor model. Results showed that Crk II knockdown by shRNA-mediated silencing (Crk II-shRNA) in the PCa cells significantly inhibited both cancer cell migration and invasion in cell culture study. Crk II-shRNA cancer cells also significantly decreased colony formation in vitro, but had no significant reduction of tumor volume after 4 weeks of cancer cell xenografting in vivo when compared to the scramble control. Interestingly, Crk II-shRNA cancer cells showed a greatly reduced level of insulin-like growth factor 1 receptor (IGF-1R) and decreased signaling of the IGF-1R/PI3K/Akt axis upon IGF-1 ligand stimulation. A close interaction between Crk II and IGF-1R was demonstrated upon co-immunoprecipitation of IGF-1R with Crk II protein. Further, treatment of cells with either proteosomal degradation or protein synthesis inhibitor showed higher proportion of ubiquitin-associated IGF-1R and faster degradation of IGF-1R in Crk II-shRNA cells in comparison with that in the control cancer cells. Taken together, these data suggest that Crk II plays an important role in the regulation of IGF-1R protein stability and affects downstream of IGF-1R signaling pathways. Therefore, targeting Crk-II can block IGF-1R growth signaling and suppress cancer cell invasion and progression. 相似文献
996.
997.
Effect of EGCG On Fe(III)‐induced conformational transition of silk fibroin,a model of protein related to neurodegenerative diseases 下载免费PDF全文
The abnormal aggregation of amyloid proteins is reported to play a critical role in the etiology of neurodegenerative disorders. Studies have shown that excessive ferric irons are associated with the misfolding of amyloid proteins, and that (‐)‐epigallocatechin gallate (EGCG) is a good metallic ion chelator with inhibitory effect on the aggregation of amyloid proteins. EGCG has been thus considered as a potential drug candidate for the treatment of neurodegenerative diseases. However, the mechanism of action for EGCG in inhibition of aggregation of amyloid proteins is still remaining unclear. Silk fibroin (SF) shares similarities with amyloid proteins in some amino acid sequences and fibrillation kinetics. In this work, therefore, we used SF as a model of protein to investigate the effects of Fe(III) and EGCG on conformational transition by using turbidity assay, thioflavin T (ThT) fluorescence spectroscopy, Raman spectroscopy, and atomic force microscope (AFM). We demonstrated that low concentration of Fe(III) ions promoted the formation of β‐sheet conformers, while high concentration of Fe(III) ions inhibited further aggregation of SF. EGCG could significantly inhibit the conformational transition of SF when induced by Fe(III), and decrease the amount of β‐sheet conformers dose‐dependently. The findings provide important information regarding to EGCG as a potential agent for the prevention and treatment of neurodegenerative diseases. Fe(III) can accelerate the conformation transition of silk fibrion (SF) from random coil into β‐sheet, while (‐)‐epigallocatechin gallate (EGCG) inhibits Fe(III)‐induced β‐sheet aggregation of SF., 2016. © 2015 Wiley Periodicals, Inc. Biopolymers 105: 100–107, 2016 相似文献
998.
Taotao Feng Xiaoyu ChenXiuwen Qiao Zhao SunHaining Wang Yu Qi Chenglin Hong 《Analytical biochemistry》2016
In this work, a simple electrochemical immunosensor was developed for the detection of carcinoembryonic antigen (CEA) based on rhombic dodecahedral Cu2O nanocrystals–graphene oxide–gold nanoparticles (rCu2O–GO–AuNPs). GO as the template and surfactant resulting in rCu2O exhibit improved rhombic dodecahedral structure uniformity and excellent electrochemical performance. Moreover, GO was found to be able to effectively improve the long stability of rCu2O on the electrode response. Under optimal conditions, the immunosensor showed a low limit of detection (0.004 ng ml−1) and a large linear range (0.01–120 ng ml−1). This work presents a potential alternative for the diagnostic applications of GO-supported special morphology materials in biomedicine and biosensors. 相似文献
999.
Yaming Sun Qing Bi Xiaoli Zhang Litao Wang Xia Zhang Shuqing Dong Liang Zhao 《Analytical biochemistry》2016
A facile capillary electrophoresis (CE) method for the separation of cinnamic acid and its derivatives (3,4-dimethoxycinnamic acid, 4-methoxycinnamic acid, isoferulic acid, sinapic acid, cinnamic acid, ferulic acid, and trans-4-hydroxycinnamic acid) using graphene quantum dots (GQDs) as additives with direct ultraviolet (UV) detection is reported. GQDs were synthesized by chemical oxidization and further purified by a macroporous resin column to remove salts (Na2SO4 and NaNO3) and other impurities. Transmission electron microscopy (TEM) indicated that GQDs have a relatively uniform particle size (2.3 nm). Taking into account the structural features of GQDs, cinnamic acid and its derivatives were adopted as model compounds to investigate whether GQDs can be used to improve CE separations. The separation performance of GQDs used as additives in CE was studied through variations of pH, concentration of the background electrolyte (BGE), and contents of GQDs. The results indicated that excellent separation can be achieved in less than 18 min, which is mainly attributed to the interaction between the analytes and GQDs, especially isoferulic acid, sinapic acid, and cinnamic acid. 相似文献
1000.