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571.
Antidiabetic potential: in vitro inhibition effects of some natural phenolic compounds on α‐glycosidase and α‐amylase enzymes 下载免费PDF全文
α‐Glycosidase is a catalytic enzyme and it destroys the complex carbohydrates into simple absorbable sugar units. The natural phenolic compounds were tested for their antidiabetic properties as α‐glycosidase and α‐amylase inhibitors. The phenolic compounds investigated in this study have been used as antidiabetic common medicines. This paper aimed to consider their capability to inhibit α‐amylase and α‐glycosidase, two significant enzymes defined in serum glucose adjustment. These examination recorded impressive inhibition profiles with IC50 values in the range of 137.36–737.23 nM against α‐amylase and 29.01–157.96 nM against α‐glycosidase. 相似文献
572.
Mohammad Ali Nisar Ahmad Haji Khan Gul Shad Ali 《Critical reviews in biotechnology》2017,37(7):833-851
The genus Artemisia has been utilized worldwide due to its immense potential for protection against various diseases, especially malaria. Artemisia absinthium, previously renowned for its utilization in the popular beverage absinthe, is gaining resurgence due to its extensive pharmacological activities. Like A. annua, this species exhibits strong biological activities like antimalarial, anticancer and antioxidant. Although artemisinin was found to be the major metabolite for its antimalarial effects, several flavonoids and terpenoids are considered to possess biological activities when used alone and also to synergistically boost the bioavailability of artemisinin. However, due to the limited quantities of these metabolites in wild plants, in vitro cultures were established and strategies have been adopted to enhance medicinally important secondary metabolites in these cultures. This review elaborates on the traditional medicinal uses of Artemisia species and explains current trends to establish cell cultures of A. annua and A. absinthium for enhanced production of medicinally important secondary metabolites. 相似文献
573.
Asma Akhtar Hasan Imran Afridi Tasneem Gul Kazi Farah Naz Talpur Sadaf Sadia Arain Jameel Ahmed Baig Noman Khan Mustafa Khan Muhammad Bilal 《Biological trace element research》2017,175(2):312-321
The pervasive smokeless tobacco (SLT) consumption and diseases related to its use is a hot topic for the public discussion. In this study, concentrations of chromium (Cr) were measured in different SLT products [snuff (dry and moist), mainpuri, and gutkha] offered and used in Pakistan. The current study was also designed to assess the Cr levels in the biological (scalp hair and blood) samples of male and female subjects, age ranged from 25 to 60 years, chewing different SLT products. For comparative purpose, the healthy persons of the same age group, who did not consume any SLT products, were selected as referents. The concentrations of Cr in SLT products and biological samples were measured by electrothermal atomic absorption spectrophotometer after microwave-assisted acid digestion. The validity and accuracy of the methodology were checked by certified reference materials (CRMs). The resulted data indicated that the adult persons, who consumed different SLT products, have 2–3 fold higher levels of Cr in biological samples as compared to referent subjects (p < 0.01). The persons, who chew/sniff different SLT products, have 50–80 and 42–82 % higher levels of Cr in their scalp hair and blood samples as related to referents. The daily intake of Cr is lower as compared to the recommended value of 50–200 μg/day. It was expected that 10 g consumption of various kinds of SLT products (snuff, mainpuri, and gutkha) may subsidize 21.2–220, 17.7–122, and 18.4–273 % of the recommended daily intake of Cr, respectively. 相似文献
574.
575.
麋鹿发情期主要活动的时间分配及行为研究 总被引:7,自引:3,他引:4
本文报道麋鹿在白天主要处于休息状态,早晨、黄昏是它们的摄食时间;成年雌体中的各项活动频率未显示出有明显差异;但雄鹿与雌鹿之间在活动时间分配上有明显差异,而且,雄鹿中的统治者与被统治者之间也表现出有所不同。在攻击行为方面,群内表现出有不同的特权形式;而在交往行为中,发现较多的频次出现于相同性别、年龄和同一阶层中。 相似文献
576.
Noor Rehman Sadiq Azam Amjad Ali Ibrar khan Muhammad Asghar Momena Ali Muhammad Waqas Farman Ullah Gul e Sehra 《Saudi Journal of Biological Sciences》2021,28(11):6568-6581
The Extended Spectrum Beta-Lactamases (ESBLs) producing bacteria is an issue of concern for clinicians resulting in minimize the treatment options. To overcome resistance mechanisms, novel inhibitors with good Absorption, Distribution, Metabolism, Excretion, and Toxicity (ADMET) properties must inhibit the ESBLs resistant genes. The current study aimed to identify the antibiotic resistance genes of ESBLs producing E. coli and a single inhibitor was designed to inhibit all the resistant proteins. The results showed that 42.9% ESBL producers had CTX-M (69.9%), TEM (63.4%), SHV (34.5%) and CTX-M-14 (17.5%) genes. The ESBLs producing isolates were resistant to cephalosporins, quinolones, and sulfonamide with Minimum Inhibitory Concentration (MICs) ranging from 64 to >256 μg/ml. To design multi inhibitory ligands, RECAP synthesis was used for the de-novo discovery of 1000 inhibitors database. Protein crystal structures were retrieved from Protein Data Base (PDB). Lipinski’s rules of five were applied to the novel inhibitors database to improve the ADMET properties. The novel inhibitors database was selected for docking simulations. Placement of the ligand was used by the London dG algorithm implemented in Molecular Operating Environment (MOE), while GBVI/WSA dG algorithm was used for final refinement. Based on docking score, visual inspection of ligands interaction with key residues, binding affinity, and binding energy of ligands with proteins, ten compounds were selected for ESBLs proteins with best ADMET properties, binding energy, and binding affinity the reported ones. These hits compounds have unique scaffolds and are predicted to be a starting point for developing potent inhibitors against antibiotic-resistant proteins. 相似文献
577.
John S. Preisser Gul Inan James M. Powers Haitao Chu 《Biometrical journal. Biometrische Zeitschrift》2019,61(1):126-137
The meta‐analysis of diagnostic accuracy studies is often of interest in screening programs for many diseases. The typical summary statistics for studies chosen for a diagnostic accuracy meta‐analysis are often two dimensional: sensitivities and specificities. The common statistical analysis approach for the meta‐analysis of diagnostic studies is based on the bivariate generalized linear‐mixed model (BGLMM), which has study‐specific interpretations. In this article, we present a population‐averaged (PA) model using generalized estimating equations (GEE) for making inference on mean specificity and sensitivity of a diagnostic test in the population represented by the meta‐analytic studies. We also derive the marginalized counterparts of the regression parameters from the BGLMM. We illustrate the proposed PA approach through two dataset examples and compare performance of estimators of the marginal regression parameters from the PA model with those of the marginalized regression parameters from the BGLMM through Monte Carlo simulation studies. Overall, both marginalized BGLMM and GEE with sandwich standard errors maintained nominal 95% confidence interval coverage levels for mean specificity and mean sensitivity in meta‐analysis of 25 of more studies even under misspecification of the covariance structure of the bivariate positive test counts for diseased and nondiseased subjects. 相似文献
578.
Halise Inci Gul Ebru Mete Sakip Emre Eren Hiroshi Sakagami Cem Yamali Claudiu T. Supuran 《Journal of enzyme inhibition and medicinal chemistry》2017,32(1):169-175
In this study, 4-[3-(4-hydroxyphenyl)-5-aryl-4,5-dihydro-pyrazol-1-yl]benzenesulfonamide (1–9) types compounds were synthesized and their chemical structures were confirmed by 1H NMR, 13C NMR and HRMS spectra. Cytotoxic and carbonic anhydrase (CA) inhibitory effects of the compounds were investigated. Cytotoxicity experiments pointed out that compound 4, (4-[5-(4-chlorophenyl)-3-(4-hydroxyphenyl)-4,5-dihydro-pyrazol-1-yl]benzenesulfonamide), exerting the highest tumor selectivity (TS) and potency selectivity expression (PSE) values, can be considered as a lead compound of this study in terms of development of novel anticancer agents. All synthesized sulfonamides showed a good inhibition profile on hCA IX and XII in the range of 53.5–923?nM and 6.2–95?nM, respectively. These compounds were 2.5–13.4 times more selective for the inhibition of hCA XII versus hCA IX, except compound 2 which had similar inhibitory action towards both isoenzymes. 相似文献
579.
Sri Lankan Twin Registry. 总被引:1,自引:0,他引:1
Athula Sumathipala Sisira Siribaddana Nimali De Silva Devaka Fernando Nihal Abeysingha Rohana Dayaratne Deepthi De Silva Narada Warnasuriya Mathew Hotopf 《Twin research》2002,5(5):424-426
Sri Lanka is an island with genetic diversity between the five main population groups. Our twin registry is the first in the developing world. Initially, we established a volunteer cohort of 4600 twin pairs through a competition advertised in the media. In addition, we have volunteer cohorts, birth registration-based cohorts through hospitals, and community-based cohorts. There is also a nationwide population-based younger twin cohort (1992-1997) traced through the Department of Birth and Death Registration. Additionally, we have adapted a Zygosity determination questionnaire and validated it. Establishing ethical guidelines for twin research was a priority because the field of bio-ethics is at an early stage of development in Sri Lanka. These guidelines were from a developing world perspective. A sister organization, the Multiple Birth Foundation, was formed to cater to twins and their special needs and to represent their interests, and several branches have been formed. We intend to build capacity by establishing a genetic lab and through crosscultural collaboration. Our vision is to establish a multidisciplinary research foundation. Based on our research findings, we plan to build services to cater to needs of twins by working with professionals, statutory services and government policy makers. 相似文献
580.
International Microbiology - Some of microorganisms identified in cave ecosystems have been reported to play a permanent and strategic role for maintaining life of these environments. Human... 相似文献