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41.
Yousafi Qudsia Amin Humaira Bibi Shabana Rafi Rafea Khan Muhammad S. Ali Hamza Masroor Ashir 《International journal of peptide research and therapeutics》2021,27(4):2685-2701
International Journal of Peptide Research and Therapeutics - Klebsiella oxytoca is a gram-negative bacterium. It is opportunistic in nature and causes hospital acquired infections.... 相似文献
42.
The large conducting arteries in vertebrates are composed of a specialized extracellular matrix designed to provide pulse dampening and reduce the work performed by the heart. The mix of matrix proteins determines the passive mechanical properties of the arterial wall1. When the matrix proteins are altered in development, aging, disease or injury, the arterial wall remodels, changing the mechanical properties and leading to subsequent cardiac adaptation2. In normal development, the remodeling leads to a functional cardiac and cardiovascular system optimized for the needs of the adult organism. In disease, the remodeling often leads to a negative feedback cycle that can cause cardiac failure and death. By quantifying passive arterial mechanical properties in development and disease, we can begin to understand the normal remodeling process to recreate it in tissue engineering and the pathological remodeling process to test disease treatments.Mice are useful models for studying passive arterial mechanics in development and disease. They have a relatively short lifespan (mature adults by 3 months and aged adults by 2 years), so developmental3 and aging studies4 can be carried out over a limited time course. The advances in mouse genetics provide numerous genotypes and phenotypes to study changes in arterial mechanics with disease progression5 and disease treatment6. Mice can also be manipulated experimentally to study the effects of changes in hemodynamic parameters on the arterial remodeling process7. One drawback of the mouse model, especially for examining young ages, is the size of the arteries. We describe a method for passive mechanical testing of carotid arteries from mice aged 3 days to adult (approximately 90 days). We adapt a commercial myograph system to mount the arteries and perform multiple pressure or axial stretch protocols on each specimen. We discuss suitable protocols for each age, the necessary measurements and provide example data. We also include data analysis strategies for rigorous mechanical characterization of the arteries. 相似文献
43.
A combined approach to data mining of textual and structured data to identify cancer-related targets
Background
We present an effective, rapid, systematic data mining approach for identifying genes or proteins related to a particular interest. A selected combination of programs exploring PubMed abstracts, universal gene/protein databases (UniProt, InterPro, NCBI Entrez), and state-of-the-art pathway knowledge bases (LSGraph and Ingenuity Pathway Analysis) was assembled to distinguish enzymes with hydrolytic activities that are expressed in the extracellular space of cancer cells. Proteins were identified with respect to six types of cancer occurring in the prostate, breast, lung, colon, ovary, and pancreas. 相似文献44.
45.
O M Amin 《The Journal of parasitology》1987,73(2):278-289
Pomphorhynchus bulbocolli Linkins in Van Cleave, 1919, was considerably more common in fishes of the river-connected Tichigan Lake than of the landlocked Silver Lake, southeastern Wisconsin. It is reported from 17 species of principal, accessory, and occasional definitive hosts (new record in Moxostoma carinatum) and from 13 species of paratenic hosts (new records in Amia calva, Ictalurus punctatus, Lepomis cyanellus, and Pomoxis nigromaculatus). Infection patterns were influenced by fish species, feeding behavior, temperature, availability of intermediate host, type of water body, fish movement, and changes in fish host community. Host roles are not fixed but are often interchangeable. A seasonal cycle in prevalence, intensity, and maturation was evident, with greatest abundance and maturation during summer and recruitment during summer and autumn. Recruitment of new infections, development, and release of eggs, however, occurred all year. Sex ratio changed from near equal in new infections to one more highly in favor of females in older adults. Female fish were considerably more frequently and heavily infected than males. No relationship with fish age (size) was evident. Worms were mostly attached in posterior intestinal locations but initial establishment sites correlated with temperature. Translocation of P. bulbocolli due to competitive exclusion in concurrent infections was not observed. The significance of extraintestinal larval forms in the cycle of transmission was noted. 相似文献
46.
Effect of neohesperidin dihydrochalcone on the activity and stability of alpha‐amylase: a comparative study on bacterial,fungal, and mammalian enzymes 下载免费PDF全文
Elaheh Kashani‐Amin Azadeh Ebrahim‐Habibi Bagher Larijani Ali Akbar Moosavi‐Movahedi 《Journal of molecular recognition : JMR》2015,28(10):605-613
Neohesperidin dihydrochalcone (NHDC) was recently introduced as an activator of mammalian alpha‐amylase. In the current study, the effect of NHDC has been investigated on bacterial and fungal alpha‐amylases. Enzyme assays and kinetic analysis demonstrated the capability of NHDC to significantly activate both tested alpha‐amylases. The ligand activation pattern was found to be more similar between the fungal and mammalian enzyme in comparison with the bacterial one. Further, thermostability experiments indicated a stability increase in the presence of NHDC for the bacterial enzyme. In silico (docking) test locates a putative binding site for NHDC on alpha‐amylase surface in domain B. This domain shows differences in various alpha‐amylase types, and the different behavior of the ligand toward the studied enzymes may be attributed to this fact. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
47.
Aman Shah Abdul Majid Amin Malik Shah Abdul Majid Zheng Qin Yin Dan Ji 《Neurochemical research》2013,38(7):1375-1393
Hydrogen sulphide (H2S) is one of three gaseous signaling molecules after nitric oxide and carbon monoxide. Various H2S donor compounds have been synthesized to study its physiological function. Among these compounds sodium hydrosulphide (NaHS), a donor of releasing H2S rapidly have shown to be protective in certain neuronal cell line but several in vivo studies have generated conflicting data. Furthermore several slow releasing H2S donors have been shown to have positive effects on cells in culture. The intracellular concentration of H2S and hence its rate of production may be a factor in keeping the balance between its neuroprotective and toxic effects. The present study was undertaken to deduce how a rapid releasing H2S donor (NaHS) as opposed to a slow releasing donor (ADTOH), affect oxidative stress related intracellular components and survival of RGC-5 cells. It was concluded that when RGC-5 cells are exposed to the toxic effects of glutamate in combination with buthionine sulfoxime (Glu/BSO), ADTOH was more efficacious in inhibiting apoptosis, scavenging reactive oxygen species (ROS), stimulation of glutathione (GSH) and gluthathione-S-transferase (GST). Western blot and qPCR analysis showed ADTOH increased the levels of Nrf2, HO-1, PKCα, p-Akt, Bcl-2 and XIAP but caused a decrease of Nfκβ and xCT greater than NaHS. This study is first to compare the efficacy of two H2S donor drugs as potential neuroprotectants and demonstrate that slow regulated release of H2S to cell culture can be more beneficial in inhibiting oxidative stress induced cell death. 相似文献
48.
Dhruti Amin 《Archives Of Phytopathology And Plant Protection》2013,46(9-10):485-504
AbstractThe present study was designed to investigate the effect of fungicide Opera 183?g/L SE on groundnut crop (either as seed or foliar treatment) to control damages and losses incurred especially by the soil borne pathogens Sclerotium rolfsii and Aspergillus niger. The results revealed that 0.15% Opera-treated seeds showed early germination, high percentage of germination, less mortality rate in S. rolfsii and A. niger-infested soil. Enhanced activities of defence-related enzymes, protein, carbohydrate and chlorophyll content up to 2–4 d were observed in Opera-treated plants as compared with untreated plants. Moreover, the application of Opera had a positive effect on yield up to 22%, green fodder at the time of harvest and no disease incidence. From the present study, it is recommended that application of Opera at 750?ml/hectare in the form of foliar treatment to groundnut plants could help in inducing resistance towards opportunistic pathogens and also could enhance the yield. 相似文献
49.
Sk. Abdul Amin Nilanjan Adhikari Shovanlal Gayen 《Journal of biomolecular structure & dynamics》2013,31(17):4528-4541
AbstractThe drug design and discovery of lipid modulators is very demanding as no new molecule has entered into the market in the last 35 years. Cholesteryl ester transfer protein (CETP) is a promising target as lipid modulators. Inhibition of the CETP enzyme reduces the risk of cardiovascular events. The first CETP inhibitor torcetrapib and related drug candidates failed in the clinical trial due to the off-target effects leading to high toxicity. Thus, newer CETP inhibitors have now paramount importance to accelerate the drug discovery efforts in the field of cardiovascular disease (CVD). In the present study, 140 benzoxazole compounds were studied by using different chemometric techniques, for example, pharmacophore mapping, molecular docking, three-dimensional quantitative structure–activity relationship comparative molecular field analysis (3D-QSAR CoMFA), topomer CoMFA and Bayesian classification, in order to generate complete and reliable information regarding the structural requirements for the CETP inhibition. The best pharmacophore hypothesis was statistically significant (regression coefficient of 0.957 and a lower root mean square of 0.890). Molecular docking study revealed that cyano-substituted compounds form hydrogen bond with targeted macromolecule. The 3D-QSAR CoMFA model also produced a leave-one-out (LOO) cross-validated Q2 of 0.527, an R2 of 0.853 and an R2Pred of 0.603. Similarly, two topomer CoMFA models were also statistically significant and reliable in terms of their Q2, R2 and R2Pred values. The Bayesian classification study also provided the excellent ROC values of 0.919 and 0.939 for training and test sets, respectively. Overall, this study may help in the rational design of newer benzoxazole type compounds with higher CETP inhibition.Communicated by Ramaswamy H. Sarma 相似文献
50.
M. Khawar Rauf Imtiaz-ud-Din Amin Badshah Marcel Gielen Masahiro Ebihara Dick de Vos Safeer Ahmed 《Journal of inorganic biochemistry》2009,103(8):1135-1144
A series of copper(I) complexes of N,N′-disubstituted thioureas, [C6H5CONHCSNHR]Cu(I)Cl where R = C6H5 (1a), 2-ClC6H4 (2a), 3-ClC6H4 (3a), 4-ClC6H4 (4a), 2,3-Cl2C6H3 (5a), 2,4-Cl2C6H3 (6a), 2,5-Cl2C6H3 (7a), 2,6-Cl2C6H3 (8a), 3,4-Cl2C6H3 (9a) and 3,5-Cl2C6H3 (10a) have been synthesized. These complexes (1a–10a) have been characterized by elemental analyses, IR, 1H and 13C NMR spectroscopy, cyclic voltammetry and single crystal XRD for 1a and 8a, and for ligand 7. The X-ray crystal structures reveal that the complexes 1a and 8a are mononuclear in the solid state in which the copper atoms adopt a distorted tetrahedral geometry. In both the cases, the neutral N,N′-disubstituted thiourea ligands have been coordinated to the Cu(I) through the sulphur atom in a terminal mode. The complexes have been screened for their in vitro cytotoxic activity in human cell lines carcinomas A498 (Renal), EVSA-T (Breast), H226 (Lung), IGROV (Ovarian), M19 (Melanoma-Skin), MCF-7 (Breast) and WIDR (Colon). They show a moderate cytotoxicity against these seven human cancer cell lines comparable to that of the less active standard chemotherapeutic drugs used for comparison. They were also screened for their anti-bacterial activity and were found less active than the standard drug Imipenem. 相似文献