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21.
A bioassay-guided phytochemical analysis of the triterpene saponins from under ground parts of Gypsophila arrostii var. nebulosa allowed the isolation of two triterpene saponins; nebuloside A, B based on gypsogenin and quillaic acid aglycone. Two new oleanane type triterpenoid saponins (nebuloside A, B) and three known saponins (13) were isolated from the root bark of Gypsophila arrostii var. nebulosa. The structures of the two new compounds were elucidated as 3-O-β-d-galactopyranosyl-(1→2)-[β-d-xylopyranosyl-(1→3)]-β-d-glucuronopyranosyl quillaic acid 28-O-β-d-glucopyranosyl-(1→3)-[β-d-xylopyranosyl-(1→3)-β-d-xylopyranosyl-(1→4)]-α-l-rhamnopyranosyl-(1→2)-β-d-fucopyranosyl ester (nebuloside A) and 3-O-β-d-xylopyranosyl-(1→3)-[β-d-galactopyranosyl(1→3)-β-d-galactopyranosyl-(1→2)]-β-d-glucuronopyranosyl gypsogenin 28-O-β-d-glucopyranosyl-(1→3)-[β-d-xylopyranosyl-(1→3)-β-d-xylopyranosyl-(1→4)]-α-l-rhamnopyranosyl-(1→2)-β-d-fucopyranosyl ester (nebuloside B), on the basis of extensive spectral analysis and chemical evidence. Nebuloside A and B showed toxicity enhancing properties on saporin a type-I RIP without causing toxicity by themselves at 15 μg/mL.  相似文献   
22.

Objective

Erythropoietin (EPO) improves cardiac function and induces neovascularisation in post-myocardial infarction heart failure. The aim of this study was to analyse the association between the serum erythropoietin level and coronary collateral development in patients with coronary artery disease and chronic total occlusion.

Methods

A total of 168 patients consisting of 117 with coronary artery disease (CAD, (62 with chronic total occlusion (CTO), 55 without CTO)) and 51 with healthy coronary arteries were included in the study. The patients were assigned as coronary artery disease without CTO (group 0), CAD with CTO (group 1: poor collateral development, group 2: good collateral development) and normal coronary arteries (group 3).

Results

There was a significant positive correlation between serum EPO levels and the Rentrop scores in angiography (r = 0.243, p = 0.001). Similarly, a positive correlation was found between serum EPO levels and the Syntax scores (r = 0.253, p = 0.001). Echocardiography revealed a negative correlation between serum EPO levels and the cardiac ejection fraction (r = ?0.210, p = 0.006).

Conclusions

Serum EPO is a useful biomarker for coronary collateral development in patients with CTO.
  相似文献   
23.
New secondary benzenesulphonamide-substituted coumarylthiazole derivatives were synthesized and their inhibitory effects on purified carbonic anhydrase I and II were evaluated using CO2 as a substrate. The result showed that all the synthesized compounds exhibited inhibitory activity on both hCA I and hCA II with N-(4-(2-oxo-2H-chromen-3-yl)thiazol-2-yl)naphthalene-2-sulphonamide (5f, IC50 value of 5.63 and 8.48?µM, against hCA I and hCA II, respectively) as the strongest inhibitor revealed from this study. Structure–activity relationship revealed that the inhibitory activity of the synthesized compounds is related to the type of the halogen and bulky substituent on the phenyl ring. In addition, the cupric reducing antioxidant capacities (CUPRAC) and ABTS cation radical scavenging abilities of the synthesized compounds were assayed. 4-methoxy-N-(4-(2-oxo-2H-chromen-3-yl)thiazol-2-yl)benzenesulphonamide (5e) exhibited the strongest ABTS and CUPRAC activity with IC50 value of 48.83?µM and A0.50 value of 23.29?µM, respectively.  相似文献   
24.
Tyramine derivatives 3–27 were synthesized by using conventional and environmental friendly ultrasonic techniques. These derivatives were then evaluated for the first time for their α-glucosidase (Sources: Saccharomyces cerevisiae and mammalian rat-intestinal acetone powder) inhibitory activity by using in vitro mechanism-based biochemical assays. Compounds 7, 14, 20, 21 and 26 were found to be more active (IC50?=?49.7?±?0.4, 318.8?±?3.7, 23.5?±?0.9, 302.0?±?7.3 and 230.7?±?4.0?μM, respectively) than the standard drug, acarbose (IC50?=?840.0?±?1.73?μM (observed) and 780?±?0.028?μM (reported)) against α-glucosidase obtained from Saccharomyces cerevisiae. Kinetic studies were carried out on the most active members of the series in order to determine their mode of inhibition and dissociation constants. Compounds 7, 20 and 26 were found to be the competitive inhibitors of α-glucosidase. These compounds were also screened for their protein antiglycation, and dipeptidyl peptidase-IV (DPP-IV) inhibitory activities. Only compounds 20, 22 and 27 showed weak antiglycation activity with IC50 values 505.27?±?5.95, 581.87?±?5.50 and 440.58?±?2.74?μM, respectively. All the compounds were found to be inactive against DDP-IV enzyme. Inhibition of α-glucosidase, DPP-IV enzymes and glycation of proteins are valid targets for the discovery of antidiabetic drugs. Cytotoxicity of compounds 327 was also evaluated by using mouse fibroblast 3T3 cell lines. All the compounds were found to be noncytotoxic. The current study describes the synthesis α-glucosidase inhibitory activity of derivatives, based on a natural product tyramine template. The compounds reported here may serve as the starting point for the design and development of novel α-glucosidase inhibitors as antidiabetic agents.  相似文献   
25.
Sulfonamide-bearing thiazole compounds were synthesized and their inhibitory effects on the activity of purified human carbonic anhydrase I and II were evaluated. Human carbonic anhydrase isoenzymes (hCA-I and hCA-II) were purified from erythrocyte cells by affinity chromatography. The inhibitory effects of the 12 synthesized sulfonamide (5al) on the hydratase and esterase activities of these isoenzymes (hCA-I and hCA-II) were studied in vitro. In relation to these activities, the inhibition equilibrium constants (Ki) were determined. The results showed that all the synthesized compounds inhibited the CA isoenzyme activity. Among them 5b was found to be the most active (IC50?=?0.35?μM; Ki: 0.33?μM) for hCA I and hCA II.  相似文献   
26.
This study was undertaken to analyze the phenolic profiles of 19 propolis samples from Turkey by using a high‐performance thin‐layer chromatographic (HPTLC) method in order to identify their plant origins. Furthermore, their antioxidant and antimicrobial activity profiles were comparatively evaluated. For the appraisal of antioxidant potential, total phenolic (TPC) and total flavonoid contents (TFC) of propolis samples were firstly determined and then their effects on free radicals were evaluated by FRAP, ABTS.+, CUPRAC, DPPH. and HPTLC‐DPPH. methods. Antimicrobial activity of propolis samples against Staphylococcus aureus (ATCC 6538), Pseudomonas aeruginosa (ATCC 15442), Escherichia coli (ATCC 11229) and Candida albicans ATCC 10231 were determined by disc diffusion and broth dilution methods. HPTLC fingerprinting analyses revealed that O‐type (botanical origin from Populus nigra L.) was the primarily available propolis type in Turkey. Moreover, 3‐O‐methylquercetin (3MQ) rich propolis was identified as a new propolis type for the first time. Principal component analysis (PCA) indicated that 3MQ‐type propolis differs from the O‐type. Antioxidant activity studies showed that O‐type of propolis possesses higher antioxidant effect than the other tested propolis types. Quercetin, caffeic acid, caffeic acid phenethyl ester (CAPE) and galangin were determined to contribute significantly to the antioxidant potential of O‐type propolis among others. Propolis extracts exerted moderate antimicrobial activity against the tested microorganisms with MIC values between the ranges of 128–512 μg/mL.  相似文献   
27.
Helophytic plants contribute significantly in phytoremediation of a variety of pollutants due to their physiological or biochemical mechanisms. Phenol, which is reported to have negative/deleterious effects on plant metabolism at concentrations higher than 500 mg/L, remains hard to be removed from the environmental compartments using conventional phytoremediation procedures. The present study aims to investigate the feasibility of using P. australis (a helophytic grass) in combination with three bacterial strains namely Acinetobacter lwofii ACRH76, Bacillus cereus LORH97, and Pseudomonas sp. LCRH90, in a floating treatment wetland (FTW) for the removal of phenol from contaminated water. The strains were screened based on their phenol degrading and plant growth promoting activities. We found that inoculated bacteria were able to colonize in the roots and shoots of P. australis, suggesting their potential role in the successful removal of phenol from the contaminated water. Pseudomonas sp. LCRH90 dominated the bacterial community structure followed by A. lowfii ACRH76 and B. cereus LORH97. The removal rate was significantly high when compared with the individual partners, i.e., plants and bacteria separately. The plant biomass, which was drastically reduced in the presence of phenol, recovered significantly with the inoculation of bacterial consortia. Likewise, highest reduction in chemical oxygen demand (COD), biochemical oxygen demand (BOD), and total organic carbon (TOC) is achieved when both plants and bacteria were employed. The study, therefore, suggests that P. australis in combination with efficient bacteria can be a suitable choice to FTWs for phenol-degradation in water.  相似文献   
28.
29.
D’Ancona  G.  Arslan  F.  Safak  E.  Weber  D.  Ince  H. 《Netherlands heart journal》2022,30(10):481-485
Netherlands Heart Journal - Data on the impact of the cumulative percutaneous left atrial appendage closure (LAAC) caseload on cardiovascular outpatient and hospitalisation costs are limited. The...  相似文献   
30.
In Vitro Cellular & Developmental Biology - Plant - A rapid and efficient in vitro micropropagation system was developed to conserve Tripleurospermum fissurale (Sosn.) E.Hossain (Asteraceae), a...  相似文献   
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