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11.
谭珍友  刘呈武 《合成化学》2017,25(10):847-850
以3-氨基-1-[3-(环己基甲氧基)苯基]丙-1-醇为原料,经氨基保护、氧化、手性还原、脱保护和成盐等5步反应合成了Emixustat,总收率30.7%,其结构经1H NMR和MS(ESI)确证。  相似文献   
12.
Aristolochic acids (AAs) are a mixture of structural-related compounds, in which aristolochic acid I (AA I) and aristolochic acid II (AA II) are reported to be correlated with Aristolochic acid nephropathy (AAN). In this work, a rapid and sensitive ultra-high-pressure liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) method was developed to determine AA I and AA II in herbal products and biological fluids. By using gradient elution with a mobile phase composed of a mixture of 10 mM ammonium formate buffer (pH 3.0) and acetonitrile, AAs could be determined within 10 min. Under optimum UHPLC-MS/MS conditions, the limit of detections was 0.14 and 0.26 ng mL−1 for AA I and AA II, respectively. Run-to-run repeatability and intermediate precision of peak area for AA I and AA II were less than 5.74% relative standard deviation (RSD). Accuracy was tested by spiking 10, 100 and 1000 ng mL−1 in rat serum and the recoveries were within 76.5-92.9%. Matrix effects were within 78.8-127.7%. The developed method was successfully applied to determine AA I and AA II in several herbal products and to investigate their pharmacokinetic behavior in female Wister rats. The result shows that the developed UHPLC-MS/MS method is efficient, sensitive, and accurate for the determination of AA I and AA II in herbal products and biological samples.  相似文献   
13.
Remdesivir (RDV), a phosphoramidate prodrug, has broad-spectrum antiviral activity. It is the first antiviral drug approved by the US Food and Drug Administration (FDA) for the treatment of COVID-19. Remdesivir is rapidly metabolized in the body to produce derivatives: alanine metabolite (RM-442) and RDV C-nucleoside (RN). Here, the phosphatase inhibitor PhosSTOP and carboxylesterase inhibitor 5,5′-dithiobis-2-nitrobenzoic acid were used to improve stability of RDV in mouse blood. We developed a rapid and sensitive LC–MS/MS method to simultaneously quantify RDV, RM-442 and RN in mouse blood. Chromatographic separation was achieved by gradient elution on an Acquity HSS T3 column. The run time was 3.2 min. The linearity ranges of the analytes were 0.5–1,000 ng/ml for RDV and 5–10,000 ng/ml for both RM-442 and RN. The method had an acceptable precision (RSD < 8.4% for RDV, RSD < 10.7% for RM-442 and RSD < 7.2% for RN) and accuracy (91.0–106.3% for RDV, 92.5–98.6% for RM-442 and 87.5–98.4% for RN). This method was successfully applied to analyze RDV, RM-442 and RN in the blood of normal and diabetic nephropathy DBA/2 J mice after intravenous injection of RDV at 20 mg/kg. The area under the concentration–time curve of RN between the normal and diabetic nephropathy mice showed a significant difference (P < 0.01).  相似文献   
14.
Aldose reductase (AR, ALR2), the first enzyme of the polyol pathway, is implicated in the pathophysiology of diabetic complications. Aldose reductase inhibitors (ARIs) thus present a promising therapeutic approach to treat a wide array of diabetic complications. Moreover, a therapeutic potential of ARIs in the treatment of chronic inflammation-related pathologies and several genetic metabolic disorders has been recently indicated. Substituted indoles are an interesting group of compounds with a plethora of biological activities. This article reviews a series of indole-based bifunctional aldose reductase inhibitors/antioxidants (ARIs/AOs) developed during recent years. Experimental results obtained in in vitro, ex vivo, and in vivo models of diabetic complications are presented. Structure–activity relationships with respect to carboxymethyl pharmacophore regioisomerization and core scaffold modification are discussed along with the criteria of ‘drug-likeness”. Novel promising structures of putative multifunctional ARIs/AOs are designed.  相似文献   
15.
Aristolochic acid (AA) causes interstitial renal fibrosis, called aristolochic acid nephropathy (AAN). There is no specific indicator for diagnosing AAN, so this study aimed to investigate the biomarkers for AAN using a proteomics method. The C3H/He female mice were given ad libitum AA–distilled water (0.5 mg/kg/day) and distilled water for 56 days in the AA and normal groups, respectively. The AA‐induced proteins in the kidney were investigated using a proteomics study, including fluorogenic derivatization with 7‐chloro‐N‐[2‐(dimethylamino)ethyl]‐2,1,3‐benzoxadiazole‐4‐sulfonamide, followed by high‐performance liquid chromatography analysis and liquid chromatography tandem mass spectrometry with a MASCOT database searching system. There were two altered proteins, thrombospondin type 1 (TSP1) and G protein‐coupled receptor 87 (GPR87), in the kidney of AA‐group mice on day 56. GPR87, a tumorigenesis‐related protein, is reported for the first time in the current study. The renal interstitial fibrosis was certainly induced in the AA‐group mice under histological examination. Based on the results of histological examination and the proteomics study, this model might be applied to AAN studies in the future. TSP1 might be a novel biomarker for AAN, and the further role of GPR87 leading to AA‐induced tumorigenesis should be researched in future studies.  相似文献   
16.
Diabetic nephropathy (DN) is one of the common diabetic complications, but the mechanisms are still largely unknown. In this study, we constructed a DN related protein-protein interaction network (DNPPIN) on the basis of RNA-seq analysis of renal cortices of DN and normal mice, and the STRING database. We analyzed DNPPIN in detail revealing nine critical proteins which are central in DNPPIN, and contained in one network module which is functionally enriched in ribosome, nucleic acid binding and metabolic process. Overall, this study identified nine critical and functionally associated protein-coding genes concerning DN. These genes could be a starting point of future research towards the goal of elucidating the mechanisms of DN pathogenesis and progression.  相似文献   
17.
Diabetes mellitus is characterized by tissue oxidative damage and impaired microcirculation, as well as worsened erythrocyte properties. Measurements of erythrocyte deformability together with determination of nitric oxide (NO) production and osmotic resistance were used for the characterization of erythrocyte functionality in lean (control) and obese Zucker diabetic fatty (ZDF) rats of two age categories. Obese ZDF rats correspond to prediabetic (younger) and diabetic (older) animals. As antioxidants were suggested to protect erythrocytes, we also investigated the potential effect of quercetin (20 mg/kg/day for 6 weeks). Erythrocyte deformability was determined by the filtration method and NO production using DAF-2DA fluorescence. For erythrocyte osmotic resistance, we used hemolytic assay. Erythrocyte deformability and NO production deteriorated during aging—both were lower in older ZDF rats than in younger ones. Three-way ANOVA indicates improved erythrocyte deformability after quercetin treatment in older obese ZDF rats only, as it was not modified or deteriorated in both (lean and obese) younger and older lean animals. NO production by erythrocytes increased post treatment in all experimental groups. Our study indicates the potential benefit of quercetin treatment on erythrocyte properties in condition of diabetes mellitus. In addition, our results suggest potential age-dependency of quercetin effects in diabetes that deserve additional research.  相似文献   
18.
Senna sophera (L.) Roxb (Common name: Kasunda, Baner) (Leguminosae) is used as traditional medicine in Africa and Asia. The compounds were isolated from methanolic extract of leaves of Senna sophera (MFCS). Compound A was identified as Hexahydroxy diphenic acid and Compound B as Kaempferol. MFCS administration to diabetic rats exhibited significant reduction in the blood sugar level and showed gain in body weight. After the treatment of 100 mg/kg of MFCS, the blood sugar level was reduced to 52.33 ± 2.83 mg/dl in comparison to the blood sugar level of vehicle control 76.66 ± 3.17 mg/dl, whereas treatment with 50 mg/kg of MFCS reduced the blood sugar level slightly (72.33 ± 2.42 mg/dl). The daily continuous administration of MFCS for a period of 21 days normalised the serum lipid levels confirming the effect of MFCS on diabetic hyperlipidemia. Treatment with MFCS also reversed the activities of antioxidants, which could be a result of decreased lipid peroxidation.  相似文献   
19.
本文分析了全视网膜激光光凝术(PRP)联合玻璃体腔内注射康柏西普对增生性糖尿病视网膜病变(PDR)患者视功能恢复的影响。选取大足区人民医院2016年8月~2018年8月收治的PDR患者86例(86眼),按照治疗方法分为手术组和联合组,各43例。手术组采用Carl Zeiss Meditec AG激光治疗仪在眼底荧光血管造影(FFA)引导下行PRP治疗,联合组则术前72 h于玻璃体腔内注射康柏西普0.1 mL,再行PRP治疗。采用ETDRS视力表测量两组患者术前和术后4个月的视力,非接触式眼压计测量眼压,光学相干断层扫描(OCT)检查黄斑中心凹视网膜厚度(CMT),FFA检查眼底视网膜无灌注区和新生血管消退情况,统计两组患者术后并发症发生情况。术后4个月,两组视力、CMT较术前均有变化,且联合组视力较手术组明显提高,CMT较手术组明显下降,差异有统计学意义(P<0.05)。联合组视网膜无灌注区和新生血管消退率均明显高于手术组,差异有统计学意义(P<0.05)。联合组术后视网膜脱离、眼高压及视网膜出血等并发症发生率为4.65%,明显低于手术组的23.26%,差异有统计学意义(P<0.05)。研究结果显示,PRP联合玻璃体腔内注射康柏西普治疗PDR,可明显提高患者视力,降低CMT,促进已形成的无灌注区或新生血管消退,延缓视网膜新生血管增殖,改善视功能,且安全性较高,值得临床推广应用。  相似文献   
20.
采用基于超高效液相色谱与串联四极杆飞行时间质谱仪(Ultra-high performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry,UHPLC-Q-TOF MS)联用的代谢组学方法,通过分析大鼠尿液内源性代谢物的变化,研究黄芩-栀子药对治疗糖尿病肾病的作用机制。利用高脂高糖饲料喂养并腹腔注射链脲佐菌素(STZ)建立糖尿病大鼠模型。给药12周后,采用UHPLC-Q-TOF MS对正常对照组、模型组、黄芩-栀子药对治疗组的尿液样品进行代谢轮廓分析。利用正交偏最小二乘判别分析(Orthogonal partial least squares discriminant analysis,OPLS-DA)对实验数据进行分析,挑选出对各组分分离贡献较大(VIP>1,p<0.05)的化合物在Human Metabolome Database(HMDB)等数据库进行质谱信息匹配,共鉴定出糖尿病肾病潜在生物标记物31个,给药后回调生物标记物16个。研究结果表明,黄芩-栀子药对通过影响胆汁酸的合成与代谢、尿毒素代谢、能量代谢、色氨酸代谢、苯丙氨酸代谢、酪氨酸代谢等通路对糖尿病肾病起到治疗作用,其中胆汁酸的合成与代谢、尿毒素代谢和能量代谢可能是黄芩-栀子药对发挥治疗作用的主要途径。与单味药相比,配伍后的药对具有了新的药理作用。  相似文献   
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