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Studies on Enantioselective Liquid–Liquid Extraction of Amino‐(4‐nitro‐phenyl)‐acetic Acid Enantiomers: Modeling and Optimization 下载免费PDF全文
Panliang Zhang Chang Liu Kewen Tang Jiajia Liu Congshan Zhou Changan Yang 《Chirality》2014,26(2):79-87
BINAP‐metal complexes were prepared as extractant for enantioselective liquid–liquid extraction (ELLE) of amino‐(4‐nitro‐phenyl)‐acetic acid (NPA) enantiomers. The influence of process variables, including types of organic solvents and metal precursor, concentration of ligand, pH, and temperature on the efficiency of the extraction, were investigated experimentally. An interfacial reaction model was established for insightful understanding of the chiral extraction process. Important parameters required for the model were determined. The experimental data were compared with model predictions to verify the model prediction, It was found that the interfacial reaction model predicted the experimental results accurately. By modeling and experiment, an optimal extraction condition with pH of 7 and host (extractant) concentration of 1 mmol/L was obtained and high enantioselectivity (αop) of 3.86 and performance factor (pf) of 0.1949 were achieved. Chirality 26:79–87, 2014. © 2013 Wiley Periodicals, Inc. 相似文献
994.
探讨从孕中期羊水中分离出人羊水祖细胞的有效方法和FIX基因修饰后的效果,为血友病B的产前治疗提供可行的基础。从镜下分离出呈致密克隆生长的梭形细胞集落,经培养传代后,通过第3代慢病毒载体将hFIX导入该细胞,经酶联免疫反应(ELISA)等方法检测hFIX的表达并检测凝血活性。用这种方法得到的羊水祖细胞呈成纤维细胞样,倍增时间为39.05 h,该细胞在不仅在蛋白水平表达干细胞表面分子SSEA4,TRA1-60,在基因水平还可检测到NANOG,OCT4,SOX2mRNA的表达。羊水祖细胞导入hFIX cDNA后,能合成并分泌hFIX蛋白,传代后48 h在上清液中的浓度为20.37%±2.77%,凝血活性16.42%±1.78%。上清液中的浓度在第4天达到平台期,为50.35%±5.42%,凝血活性可达45.34%±4.67%。ELISA检测显示转染后的羊水细胞表达的hFIX蛋白的水平呈现基本稳定趋势,波动幅度较小;同时检测FIX凝血活性也与蛋白浓度呈正相关。从羊水中可以分离得到具有多能性祖细胞,转染了hFIX的羊水祖细胞在体外能持续合成有凝血功能的hFIX蛋白,为血友病B产前治疗的新方法提供了实验依据。 相似文献
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Hongyu Quan Hao Tang Li Fang Jianjun Bi Yunsheng Liu Hongli Li 《Cell biochemistry and biophysics》2014,69(1):169-178
Insulin-like growth factor 1 (IGF1)(CA)19 and insulin-like growth factor-binding protein-3 (IGFBP-3)-202A/C gene polymorphisms had been focused by many epidemiological studies recently, which were associated with common cancer risk including colorectal, breast, prostate, and lung cancer. However, the findings of epidemiological investigations are not coincident. We did a systematic review and meta-analysis of case–control studies, including studies nested in cohorts, of the association between IGF1(CA)19 and IGFBP-3-202A/C gene polymorphism and prostate, colorectal, premenopausal and postmenopausal breast cancer. We identified 17 eligible studies (24 datasets), which included 9,744 cases and 11,332 controls. The result displays that individuals carrying (CA)19 allele had a subtly decreased risk of all cancer sites [OR(95 % CI) 0.92(0.87,0.97); 0.882(0.809,0.962); 0.902(0.849,0.958)] and postmenopausal breast cancer [OR(95 % CI) 0.893(0.832,0.959); 0.834(0.719,0.968); 0.862(0.776,0.958)] in allele contrast model, CA19/CA19 vs. non-CA19/non-CA19 model, and recessive genetic model. In subgroup analysis according to ethnicities, (CA)19 repeat polymorphism had an increased risk of common cancers in Asian [OR (95 % CI) of allele contrast model: 1.105(1.000,1.224); additive model: 1.103(0.844,1.441), 1.197(1.013,1.413); recessive model: 1.039(0.831,1.300); and dominant model: 1.191(1.030,1.376)]. On the other hand, IGFBP-3-202A/C gene polymorphism did not seem to be associated with all the cancer sites in any genetic model and ethnicity. In conclusion, the result of this meta-analysis indicates that the IGF1(CA)19 polymorphism is a candidate gene polymorphism for cancer susceptibility regardless of environmental factors, especially in Asian. 相似文献
997.
Yachen Zhang Yu Chen Min Zhang Yong Tang Yuquan Xie Xiaohong Huang Yigang Li 《Cell biochemistry and biophysics》2014,70(3):1791-1798
This study aims to explore the changes in calcium regulation in the sarcoplasmic reticulum (SR) during doxorubicin (DOX) treatment. Sprague–Dawley rats were treated with intravenous DOX (1.5 mg/kg) twice weekly for 12 treatments. The hemodynamic changes, myocardial oxidative stress, levels of cardiac toxicity markers, and calcium handling of the myocardial SR were observed. When the accumulation of DOX reached 12 mg/kg, (1) heart weight, left ventricular mass, and lung congestion increased significantly, and ascites appeared; (2) SBP, DBP, MAP, +dP/dt, ?dP/dt, and LVSP decreased significantly, and LVEDP increased (p < 0.01); (3) the iNOS activity and MDA and NO concentrations significantly increased, while the SOD decreased (p < 0.05 or 0.01); (4) the serum level of the AST, LDH CPK, cTnI, and BNP increased significantly (p < 0.01); (5) during DOX treatment, the rat SR Ca2+ absorption function and Ca2+-stimulated ATPase activity declined dramatically, as did the SERCA2 and phospholamban levels (p < 0.01). As expected, all these changes became evident with DOX accumulation in vivo (p < 0.05 or 0.01). In conclusion, DOX induces SR calcium regulation dysfunction via the decrease of SERCA2 and phospholamban expressions in rats. 相似文献
998.
Wei Qu Shanshan Gu Han Luo Qianying Tang Junwei Guo 《Cell biochemistry and biophysics》2014,70(3):1799-1802
The objective of the study was to explore the effects of olanzapine–fluoxetine combination (OFC) treatment of major depressive disorders on the quality of life in the acute treatment period. Methods were prospective and observational design. One hundred and three patients of major depressive disorders were observed. One group of 53 patients received OFC treatment (OFC group); the other group of 50 patients received the treatment of duloxetine (duloxetine group). Two groups were needed to be observed 8 weeks. Observed indicators were Hamilton Depression Rating Scale for Depression (HAMD-24) and four factor scores: the slow, sleep disorders, anxiety/somatization, and hopelessness, Clinical Global Impression-Severity of Illness (CGI-S), WHO quality of life scale (WHOQOL-BREF), and sub-rate measurements. HAMD-24 and four factor scores observation time were assessed before and after treatment; 1, 2, 4, 8 weeks, WHOQOL-BREF score, and sub-time measurements were assessed before treatment and 8 weeks after treatment. HAMD-24 scores of OFC patients in the first week were significantly lower than those of the duloxetine group. The sleep factor scores of OFC patients were significantly lower than those of the duloxetine group in 4 and 8 weeks. By the end of 8 weeks, OFC group was rated significantly lower than the duloxetine group in the physical area. In the acute treatment period, OFC treatment effected faster than the single duloxetine in patients with major depressive disorders. OFC effected within 1 week and was better than the single duloxetine in improving the sleep and physical conditions. 相似文献
999.
Chun-Yan Ma Shuang Liu Qing Zhang Jun Yang Li Tang Gabriel Yip Cheuk-Man Yu 《Cell biochemistry and biophysics》2014,69(1):115-121
The normal data of left ventricular (LV) synchronicity by real-time 3-dimensional echocardiography (RT3DE) are lacking. We assessed the normal range/cutoff values of LV dyssynchrony parameters by RT3DE. For this purpose, RT3DE was performed in 130 healthy subjects, aged 53 ± 12 years. Time to the point of minimal regional systolic volume (Tmsv) was measured from time–volume curves in each segment. Standard deviation (SD) and maximal difference (Dif) of Tmsv were calculated from 16 (6 basal/6 mid/4 apical), 12 (6 basal/6 mid), and 6 (basal) LV segments together with the corresponding parameters adjusted by R–R interval. The data show non-significant difference between Tmsv-16-SD (9.24 ± 3.54 ms) and Tmsv-12-SD (8.80 ± 3.82 ms); with a correlation between two by both unadjusted (ms; r = 0.87) and adjusted (%R–R; r = 0.84) methods (P < 0.001). Heart rate correlated negatively with Tmsv (r = ?0.13 to ?0.34, P < 0.05–0.001) but had no effect on parameters adjusted for %R–R. Age and gender did not affect any of these parameters. Inter-observer variability was 3.3–4.6 % for 16, 4.8–9.1 % for 12, and 14.4–19.7 % for 6 segments. Thus, RT3DE is a reliable technique for detecting LV systolic dyssynchrony whereas the heart rate, but not age and gender, affects Tmsv parameters. Dyssynchrony parameters by 16 or 12 segments are superior to 6 segments in yielding comprehensive information and lower variability. 相似文献
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