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51.
Bahareh Eftekharzadeh Javad Hamedi Fatemeh Mohammadipanah Fariba Khodagholi Nader Maghsoudi Hans Peter Klenk 《Applied microbiology and biotechnology》2010,86(6):1805-1811
Actinomycetes isolated from Iran soil habitats were tested for the capacity to produce compounds which can protect neurons
from cell death generated by oxidative stress in NT2 neurons. Confirmation of our initial hit was accomplished via the determination
of amyloid β level using the enzyme-linked immunosorbent assay test. The most interesting amyloid β formation inhibitor discovered
in our study was a secondary metabolite which was produced by strain HM45. This bioactive strain was identified as a strain
of Streptomyces antibioticus DSM 40234 using polyphasic approach. The strain HM45 was deposited in Deutsche Sammlung von Mikroorganismen und Zellkulturen
as S. antibioticus DSM 41955 and University of Tehran Microorganisms Sollection as S. antibioticus UTMC 00105. This work is the first report on efficiency of an actinomycete metabolite in prohibition of neurons death caused
by amyloid β formation. 相似文献
52.
Fatemeh Daneshmand Mohammad Javad Arvin Khosrow Manouchehri Kalantari 《Acta Physiologiae Plantarum》2010,32(1):91-101
In this study, responses of wild species of potato to NaCl stress were investigated in vitro. In S. stoloniferum and S. bulbosum, length of the shoot, fresh and dry weight, photosynthetic pigments, K+ concentration, K+/Na+ ratio, ascorbate pool, anthocyanin, and phenolic and flavonoid compounds were decreased in response to salinity. In these species, salinity increased the level of Na+, lipid peroxidation, proline and ion leakage percentage. In S. acaule, the length of the shoot, and fresh and dry weight were not affected by salinity. Photosynthetic pigments, Na+ concentration, proline, flavonoid and phenolic compounds quantities were increased and K+/Na+ ratio were decreased. K+ concentration, lipid peroxidation, ascorbate pool, anthocyanin and ion leakage were not changed by NaCl stress. Superoxide dismutase, guaiacol peroxidase, ascorbate peroxidase and catalase activities were increased in all species. The results suggest that the non-enzymatic antioxidant capacity in S. acaule (salt tolerant) is more important than the enzymatic antioxidant capacity in comparison with the other species. 相似文献
53.
Signals can be perceived and amplified at the cell membrane by receptors coupled to the production of a variety of second messengers, including myoinositol 1,4,5-trisphosphate [Ins(1,4,5)P(3)]. The myoinositol polyphosphate 5-phosphatases (5PTases; EC 3.1.3.56) comprise a large protein family that hydrolyzes 5-phosphates from a variety of myoinositol phosphate (InsP) and phosphoinositide phosphate (PtdInsP) substrates. Arabidopsis thaliana has 15 genes encoding 5PTases. Biochemical analyses of a subgroup of 5PTase enzymes suggest that these enzymes have both overlapping and unique substrate preferences. Ectopic expression of these genes in transgenic plants can reduce Ins(1,4,5)P(3) levels and alter abscisic acid (ABA) signaling. To further explore the function of 5PTases in signaling, we have identified and characterized T-DNA insertional mutants for 5PTase1 and 5PTase2 and produced a double mutant. When grown in the dark, the seeds from these mutants germinate faster than wild-type seeds and the mutant seedlings have longer hypocotyls than wild-type seedlings. Seeds from these mutant lines also demonstrate an increase in sensitivity to ABA. These changes in early seedling growth are accompanied by mass increases in Ins(1,4,5)P(3), but not by changes in endogenous ABA content. By labeling the endogenous myoinositol pool in 5ptase1 and 5ptase2 mutants, we detected increases in Ins(1,4,5)P(3) and a decrease in PtdIns, PtdIns(4)P, and phosphatidylinositol (4,5) bisphosphate. Taken together, these data indicate that the At5PTase1 and At5PTase2 genes have nonredundant roles in hydrolyzing inositol second-messenger substrates and that regulation of Ins(1,4,5)P(3) levels is important during germination and early seedling development. 相似文献
54.
Edupuganti OP Antoci V King SB Jose B Adams CS Parvizi J Shapiro IM Zeiger AR Hickok NJ Wickstrom E 《Bioorganic & medicinal chemistry letters》2007,17(10):2692-2696
Self-protecting Ti6Al4V alloy pins were prepared by covalent bonding of bis(ethylene glycol) linkers, then vancomycin to the oxidized, aminopropylated Ti6Al4V alloy surface. Fluorescence modification-enabled estimation of yields of free amines on the metallic surface monolayer at each reaction step. The vancomycin-protected Ti6Al4V pins were not colonized by Staphylococcus aureus, even after 44days storage in physiological buffer. These results provide a basis for testing self-protection against S. aureus colonization in animal models. 相似文献
55.
Background
The incidence of Hypertension as a major cardiovascular threat is increasing. The best known diet for hypertensives is 'no added salt diet'. In this study we evaluated the effect of 'no added salt diet' on a hypertensive population with high dietary sodium intake by measuring 24 hour urinary sodium excretion.Methods
In this single center randomized study 80 patients (60 cases and 20 controls) not on any drug therapy for hypertension with mild to moderate hypertension were enrolled. 24 hour holter monitoring of BP and 24 hour urinary sodium excretion were measured before and after 6 weeks of 'no added salt diet'.Results
There was no statistically significant difference between age, weight, sex, Hyperlipidemia, family history of hypertension, mean systolic and diastolic BP during the day and at night and mean urinary sodium excretion in 24 hour urine of case and control groups. Seventy eight percent of all patients had moderate to high salt intake. After 6 week of 'no added salt diet' systolic and diastolic BP significantly decreased during the day (mean decrease: 12.1/6.8 mmhg) and at night (mean decrease: 11.1/5.9 mmhg) which is statistically significant in comparison to control group (P 0.001 and 0.01). Urinary sodium excretion of 24 hour urine decreased by 37.1 meq/d ± 39,67 mg/dl in case group which is statistically significant in comparison to control group (p: 0.001). Only 36% of the patients, after no added salt diet, reached the pretreatment goal of 24 hour urinary sodium excretion of below 100 meq/dl (P:0.001).Conclusion
Despite modest effect on dietary sodium restriction, no added salt diet significantly decreased systolic and diastolic BP and so it should be advised to every hypertensive patient.Trial Registration
Clinicaltrial.govnumber NCT00491881 相似文献56.
Karimzadeh Soureshjani Hedayatollah Nezami Ahmad Nabati Jafar Oskoueian Ehsan Ahmadi-Lahijani Mohammad Javad 《Journal of Plant Growth Regulation》2022,41(3):1109-1124
Journal of Plant Growth Regulation - Fall cultivation of field crops such as chickpea is prone to the risk of freezing stress. It is required to identify the mechanisms through which plants can... 相似文献
57.
Rommasi Foad Nasiri Mohammad Javad Mirsaeidi Mehdi 《Molecular and cellular biochemistry》2022,477(3):711-726
Molecular and Cellular Biochemistry - The novel coronavirus pandemic has emerged as one of the significant medical-health challenges of the current century. The World Health Organization has named... 相似文献
58.
Gholipour Akram Shakerian Farshad Zahedmehr Ali Oveisee Maziar Maleki Majid Mowla Seyed Javad Malakootian Mahshid 《Molecular biology reports》2022,49(10):9267-9273
Molecular Biology Reports - Coronary artery disease (CAD), is the leading cause of mortality and morbidity worldwide. Tenascin-C (TNC) with high expression levels in inflammatory and cardiovascular... 相似文献
59.
60.
Inhibitory Effect of Hsa‐miR‐590‐5p on Cardiosphere‐derived Stem Cells Differentiation Through Downregulation of TGFB Signaling 下载免费PDF全文