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91.
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93.
Amirhossein Sahebkar Mahdi Hatamipour Sayed Abbas Tabatabaei 《Journal of cellular biochemistry》2019,120(6):9455-9459
Disruption of macrophage autophagy is a major contributor to macrophage dysfunction and subsequent inflammation leading to atherosclerosis. Trehalose is a natural disaccharide that is able to induce macrophage autophagy-lysosomal biogenesis and reduce inflammation. Here, we studied the efficacy of intravenous trehalose administration in reducing atherosclerotic plaque burden in high-cholesterol-fed rabbits. Adult male New Zealand white Rabbits were fed with a high-fat diet containing 1% cholesterol for 8 weeks followed by a cholesterol-free diet for the next 4 weeks. In the latter 4-week phase of the cholesterol-free diet, one group received intravenous trehalose solution at a dose of 350 mg/kg, three times per week. In the control group, an equivalent volume of PBS (3 mL) was administered with the same protocol. At the end of the 12th week of the study, all rabbits were anesthetized and aortic arch sections were collected followed by hematoxylin and eosin staining and assessment of plaque grading. Fasting serum lipids were also measured using routine enzymatic methods. At the end of the 12th week, there were no significant differences in the body weight and blood lipids between the control- and trehalose-treated groups. Intravenous trehalose administration significantly attenuated atherosclerotic plaque development as revealed by reduced plaque grading ( P = 0.048) and intima/media thickness ratio ( P = 0.017). Intimal thickening was also found to be reduced in the trehalose versus control group, though this reduction did not reach statistical significance. The present study provided evidence as to the efficacy of short-term intravenous trehalose administration in regressing atherosclerotic plaque in high-fat-fed rabbits. 相似文献
94.
Shirin Kouhpayeh Zahra Hejazi Maryam Boshtam Mina Mirian Ilnaz Rahimmanesh Leila Darzi Abbas Rezaei Laleh Shariati Hossein Khanahmad 《Journal of cellular biochemistry》2019,120(9):16264-16272
One of the most important molecules for multiple sclerosis pathogenesis is α4 integrin, which is responsible for autoreactive leukocytes migration into the brain. The monoclonal antibody, natalizumab, was introduced to market for blocking the extravasation of autoreactive leukocytes via inhibition of α4 integrin. However, the disadvantages of antibodies provided a suitable background for other agents to be replaced with antibodies. Considering the profound advantages of aptamers over antibodies, aptamer isolation against α4 integrin was intended in the current study. The α4 integrin-specific aptamers were selected using cell-systematic evolution of ligands by exponential enrichment (SELEX) method with human embryonic kidney (HEK)-293T overexpressing α4 integrin and HEK-293T as target and control cells, respectively. Evaluation of selected aptamer was performed through flow cytometric analysis. The selected clones were then sequenced and analyzed for any possible secondary structure and affinity. The results of this study led to isolation of 13 different single-stranded DNA clones in 11 rounds of selection which were categorized to three clusters based on common structural motifs and the equilibrium dissociation constant (K d) of the most stable structure was calculated. The evaluation of SELEX progress showed growth in aptamer affinity with increasing of the number of cycles. Taken together, the findings of this study demonstrated the isolation of α4-specific single-stranded DNA aptamers with suitable affinity for ligand, which can further be replaced with natalizumab. 相似文献
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96.
Abbas HK Cartwright RD Xie W Mirocha CJ Richard JL Dvorak TJ Sciumbato GL Shier WT 《Mycopathologia》1999,147(2):97-104
Twenty samples of unpolished (rough) rice collected in Arkansas and Texas during the 1995 harvesting season from fields exhibiting
Fusarium sheath rot disease or panicle blight were previously shown to include 8 samples positive for fumonisin B1(FB1) in the range 2.2–5.2 ppm, and moniliformin (MON), but no beauvericin (BEA), deoxynivalenol, its derivatives or zearalenone
were detected. Fifteen cultures of F. proliferatum were established from the 20 rough rice samples. Single spore isolates of each culture were grown on rice and tested for
the production of fumonisins (FB1, FB2, FB3, etc.), MON and BEA. All 15 isolates produced FB1, FB2, MON and BEA in culture on rice. No deoxynivalenol, its derivatives orzearalenone were detected. Seven cultures produced
FB1 at >50ppm (range 80–230 ppm), with therest producing FB1 in the range 14–43 ppm.FB2 was produced in the range 5–47 ppm, and those cultures which produced the most FB1 also produced the most FB2. Of the 15 cultures producing MON, 11 produced it at >100 ppm in the range 188–6018 ppm, with the rest producing in the range
7–64 ppm. BEA was produced in the range 109–1350 ppm. Other derivatives of fumonisins, including FA1, FA2 and partially hydrolyzed FB1, as well asseveral unknown metabolites including a compound with MW 414, were identified in culture extracts by continuous
flow fast atom bombardment with ion spraymass spectrometry (CF/FAB/MS). Further study is needed to identify the factors that
control production of FB1, MON and BEA by F.proliferatu in culture and in field samples.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
97.
Almasirad A Tabatabai SA Faizi M Kebriaeezadeh A Mehrabi N Dalvandi A Shafiee A 《Bioorganic & medicinal chemistry letters》2004,14(24):191-6059
A series of new 2-substituted-5-[2-(2-fluorophenoxy)phenyl]-1,3,4-oxadiazoles has been synthesized and screened for their anticonvulsant activities. Compound 3 shows considerable anticonvulsant activity both in PTZ and MES models. It seems that this effect is mediated by benzodiazepine receptors and other unknown mechanism, respectively. 相似文献
98.
(E)- and (Z)-1,2,4-triazolylchromanone oxime ethers as conformationally constrained antifungals 总被引:1,自引:0,他引:1
Emami S Falahati M Banifatemi A Amanlou M Shafiee A 《Bioorganic & medicinal chemistry》2004,12(15):3971-3976
A series of 1,2,4-triazolylchromanone oxime ethers were synthesized and tested for in vitro antifungal activity. Many of these derivatives exhibit high activity against Candida albicans, Saccharomyces cerevisiae, Aspergillus niger and Microsporum gypseum. 相似文献
99.
Wallin C Abbas AK Tranberg M Weber SG Wigström H Sandberg M 《Neurochemical research》2003,28(2):281-291
N-Methyl-d-aspartate (NMDA)-receptor stimulation evoked a selective and partly delayed elevated efflux of glutathione, phosphoethanolamine, and taurine from organotypic rat hippocampus slice cultures. The protein kinase inhibitors H9 and staurosporine had no effect on the efflux. The phospholipase A2 inhibitors quinacrine and 4-bromophenacyl bromide, as well as arachidonic acid, a product of phospholipase A2 activity, did not affect the stimulated efflux. Polymyxin B, an antimicrobal agent that inhibits protein kinase C, and quinacrine in high concentration (500 µM), blocked efflux completely. The stimulated efflux after but not during NMDA incubation was attenuated by a calmodulin antagonist (W7) and an anion transport inhibitor (DNDS). Omission of calcium increased the spontaneous efflux with no or small additional effects by NMDA. In conclusion, NMDA receptor stimulation cause an increased selective efflux of glutathione, phosphoethanolamine and taurine in organotypic cultures of rat hippocampus. The efflux may partly be regulated by calmodulin and DNDS sensitive channels. 相似文献
100.
Abdollahi A Gruver BN Patriotis C Hamilton TC 《Biochemical and biophysical research communications》2003,307(1):188-197
Alteration in epidermal growth factor receptor (EGFR) family signaling is among the most frequently implicated effectors of human oncogenesis. Overexpression of members of this family of receptors has often been detected in many epithelial tumors and is believed to be associated with an overall poor prognosis in patients with cancer. Therefore, we hypothesized that identification of potential EGF target genes in normal cells will provide a basis for unbiased genetic analysis of this signaling pathway in cancer. We utilized Atlas Rat 1.2 nylon cDNA arrays (Clontech) to determine gene expression changes in normal rat ovarian surface epithelial (ROSE) cells following EGF treatment. The results indicate activation of genes involved in a wide variety of cellular mechanisms, including regulation of cell cycle and proliferation, apoptosis, and protein turnover. In addition, using an in vitro model of ovarian cancer, we demonstrated that malignant transformation of ROSE cells resulted in alteration of downstream effectors of the EGFR pathway, as exemplified by aberrant expression of p66Shc, c-Jun, c-Myc, c-Fos, Lot1, p21Cip/Waf, and cdc25A. These data suggest that knowledge of the downstream genetic lesions, which may result in loss of growth factor requirement of the affected cells, will be crucial for the selection of the EGFR pathway as an effective target for cancer therapy. 相似文献