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41.
《Phytomedicine》2014,21(5):704-711
Extract of Acanthopanax senticosus harms (EAS) has been shown to have neuroprotective effects on dopaminergic neurons in Parkinson's disease (PD) mice model. α-Synuclein is a key player in the pathogenesis of PD, the elevated level of which is deleterious to dopaminergic neurons, and enhancing its clearance might be a promising strategy for treating PD. To assess the potential of EAS in this regard, we investigated its effect on the SH-SY5Y cells overexpressing wild-type α-synuclein (WT-α-Syn) or A53T mutant α-synuclein (A53T-α-Syn), and the implicated pathway it might mediate. After treatment with EAS, the changes of α-synuclein, caspase-3, parkin, phospho-protein kinase B (Akt), phospho-glycogen synthase kinase 3 beta (GSK3β), and phospho-microtubule-associated protein tau (Tau) in WT-α-Syn or A53T-α-Syn transgenic cells were reverted back to near normal levels, demonstrated by the western blotting and quantitative real-time PCR outcomes. The neuroprotective effects of EAS may be able to protect WT-α-Syn or A53T-α-Syn transgenic SH-SY5Y cells from α-synuclein overexpression and toxicity. Therefore, we speculate that EAS might be a promising candidate for prevention or treatment of α-synuclein-related neurodegenerative disorders such as PD. 相似文献
42.
《Process Biochemistry》2014,49(5):882-889
The VP4 protein of infectious bursal disease virus (IBDV) is a serine protease that processes the polyprotein for viral assembly. VP4 has been found to associate primarily with type II IBDV tubules that are 24 nm in diameter. In this study, a chimeric VP4, assigned as HS1VP4, was constructed with a VP4-autocleavage site inserted between the N-terminal His-tag and the VP4 sequence. The results showed that the VP4 forms tubules after the self-cleavage of HS1VP4 when expressed in Escherichia coli. Furthermore, a deletion of 28 amino acids at the C-terminus of VP4 resulted in monomers and dimers instead of tubule formation; mutants of S652A and K692A at active site destroyed the activity. The endopeptidase activity of these monomers and dimers was approximately 12.5 times higher than that of VP4 tubules. Additionally, the formation of tubules inhibited VP4 protease activity, as demonstrated through in vitro assays. The production and characterization of monomers or dimers that have greater endopeptidase activity and protease activity than tubules can provide further insight into VP4 tubule assembly and the regulation of VP4 activity in host cells; this insight will facilitate the development of new anti-IBDV strategies. 相似文献
43.
A. Benito E. Viaplana J.L. Corchero X. Carbonell A. Villaverde 《FEMS microbiology letters》1995,129(2-3):157-162
Abstract The 3D gene of foot-and-mouth disease virus encodes the viral RNA dependent RNA polymerase, also called virus infection associated (VIA) antigen, which is the most important serological marker of virus infection. This 3D gene from a serotype Cl virus has been cloned and overexpressed in Escherichia coli under the control of the strong lambda lytic promoters. The resulting 51 kDa recombinant protein has been shown to be immunoreactive with sera from infected animals. After induction of gene expression, an immediate and dramatic arrest of cell DNA synthesis occurs, similar to that produced by genotoxic doses of the drug mitomycin C. This effect does not occur during the production of either a truncated VIA antigen or other related and non-related viral proteins. The inhibition of DNA replication results in a subsequent induction of the host SOS DNA-repair response and in an increase of the mutation frequency in the surviving cells. 相似文献
44.
A series of thirty (30) thiazole analogs were prepared, characterized by 1H NMR, 13C NMR and EI-MS and evaluated for Acetylcholinesterase and butyrylcholinesterase inhibitory potential. All analogs exhibited varied butyrylcholinesterase inhibitory activity with IC50 value ranging between 1.59 ± 0.01 and 389.25 ± 1.75 μM when compared with the standard eserine (IC50, 0.85 ± 0.0001 μM). Analogs 15, 7, 12, 9, 14, 1, 30 with IC50 values 1.59 ± 0.01, 1.77 ± 0.01, 6.21 ± 0.01, 7.56 ± 0.01, 8.46 ± 0.01, 14.81 ± 0.32 and 16.54 ± 0.21 μM respectively showed excellent inhibitory potential. Seven analogs 15, 20, 19, 24, 28, 30 and 25 exhibited good acetylcholinesterase inhibitory potential with IC50 values 21.3 ± 0.50, 35.3 ± 0.64, 36.6 ± 0.70, 44.81 ± 0.81, 46.36 ± 0.84, 48.2 ± 0.06 and 48.72 ± 0.91 μM respectively. All other analogs also exhibited well to moderate enzyme inhibition. The binding mode of these compounds was confirmed through molecular docking. 相似文献
45.
46.
《Developmental cell》2022,57(22):2533-2549.e7
47.
S M Duray 《American journal of physical anthropology》1990,81(1):27-34
Clinical studies of the relationship between developmental enamel defects and caries susceptibility have often produced conflicting results. This has been due in part to a failure to distinguish between different types of defects. Studies of this association in prehistoric populations have been rare. The complete deciduous dentitions of 57 subadults from the Libben site, a large Late Woodland cemetery in Ottawa County, Ohio, were selected for analysis. Defects were classified as either hypoplasias (deficiencies in matrix apposition) or hypocalcifications (deficiencies in mineralization) and were graded for severity. The presence or absence of carious lesions was recorded for each tooth. Results indicate a strong positive relationship between hypocalcifications and caries susceptibility. The elevated caries susceptibility of hypocalcified teeth may be related to high levels of magnesium or altered enamel microcrystallite orientation within these teeth. Variations in the frequency of hypocalcifications may partially explain differences in caries rates that have been observed in different prehistoric populations. 相似文献
48.
Olga A. Grishina Irina V. Kirillova Olga E. Glukhova 《Computer methods in biomechanics and biomedical engineering》2016,19(3):297-305
The biomechanical model of human coronary arteries was modified for improving the quality of diagnosis and surgical treatment for coronary heart disease. The problem of hemodynamics in the left coronary artery with multivessel bed disease – 45% stenosis of the anterior descending branch and 75% stenosis of the circumflex branch – was particularly considered. Numerical simulation of the coronary arterial bypass of the main trunk was carried out to estimate the functional condition of the coronary arteries after restoring myocardial blood supply by surgery. 相似文献
49.
Cynthia Nafula Wakhungu Isaiah Masinde Tabu O. Daniel Otaye Wafula Victor Wasike 《Archives Of Phytopathology And Plant Protection》2017,50(7-8):398-414
A study was carried out to determine Fusarium wilt distribution in Bambara nut farmers’ fields and its management using farm yard manure (FYM). Four villages in Busia County were purposively sampled for the study. The data generated were subjected to analysis of variance and treatment means separated by least significant difference test. Fusarium wilt incidence in the fields ranged from 14.63 to 43.56%. In the greenhouse, FYM reduced the disease incidence by 10.2% and severity by 9.5% on the black landrace and 1.9 and 12.8%, respectively, on the red landrace. In the field, FYM reduced disease incidence by 9.1% and severity by 6.9% on the black landrace and 10.4 and 10.4%, respectively, on the red landrace. Farm yard manure had the lowest area under disease progress curve irrespective of the landrace. The study confirmed the presence of the pathogen in the fields and the ability to manage the disease using FYM. 相似文献
50.
《Free radical research》2013,47(2):82-88
AbstractEndothelial dysfunction characterized by decreased nitric oxide (NO) bioavailability is the first stage of coronary artery disease. It is known that one of the factors associated with an increased risk of coronary artery disease is a high plasma level of uric acid. However, causative associations between hyperuricaemia and cardiovascular risk have not been definitely proved. In this work, we tested the effect of uric acid on endothelial NO bioavailability. Electrochemical measurement of NO production in acetylcholine-stimulated human umbilical endothelial cells (HUVECs) revealed that uric acid markedly decreases NO release. This finding was confirmed by organ bath experiments on mouse aortic segments. Uric acid dose-dependently reduced endothelium-dependent vasorelaxation. To reveal the mechanism of decreasing NO bioavailability we tested the effect of uric acid on reactive oxygen species production by HUVECs, on arginase activity, and on acetylcholine-induced endothelial NO synthase phosphorylation. It was found that uric acid increases arginase activity and reduces endothelial NO synthase phosphorylation. Interestingly, uric acid significantly increased intracellular superoxide formation. In conclusion, uric acid decreases NO bioavailability by means of multiple mechanisms. This finding supports the idea of a causal association between hyperuricaemia and cardiovascular risk. 相似文献