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51.
J Chełkowski P Goliński J. Perkowski A Visconti M Rakowska W Wakuliński 《Mycotoxin Research》1991,7(2):140-145
Microdochium nivale (Fusarium nivale) was found to be frequently occuring in Poland pathogen of small grain cereals heads, causing symptoms similar to those observed after infection ofFusarium species. In consecutive years since 1985 till 1989 the following percentage of wheat and rye ears infected withM. Nivale and withFusarium head blight symptoms was found: 34%, 21%, 42%, 9%, 46% (wheat) and 57%, 43%, 65%, 4%, 47% (rye) heads.However, in naturally infected rye and wheat samples (kernels and chaff), we did not detect toxins usually present in samples infected with fungi of genusFusarium — such as deoxynivalenol and derivatives. TypicalFusarium trichothecene metabolites were also not present in cultures of 11M. nivale strains, growing 3–5 weeks on rice (45% water content) at 20°C. Cultures of two typical isolates on wheat grain (strain KF 1124) and on rice (KF 245) were found to be non toxic to broiler chickens when present in amount 20–40% in their diet. It can be concluded thatM. nivale (F. nivale) representatives in Poland did not produce toxic metabolites neither under laboratory condition nor after cereal ears infection under field conditions. 相似文献
52.
Fereshteh Shiri Somayeh Pirhadi Jahan B. Ghasemi 《Journal of biomolecular structure & dynamics》2019,37(7):1800-1812
Acetylcholinesterase is a critical enzyme that regulates neurotransmission by catalyzing the breakdown of neurotransmitter acetylcholine in synapses of the nervous system. It is an important target for therapeutic drugs that treat Alzheimer’s disease. Since, the degree of flexibility of the side chains of the residues in the active-site gorge of Acetylcholinesterase is diverse it results in different bound ligand conformations. The side-chain conformations of Ser293, Tyr341, Leu76, and Val73 are flexible, while the side-chain conformations of Tyr72, Tyr 124, Ser125, Phe295, and Arg296 appear to be fixed. In this study, multi-conformation dynamic pharmacophore models from the donepezyl-binding pocket based on highly populated structures chosen from molecular dynamics simulations were used for screening compounds that can properly bind acetylcholinesterase. Based on these structures, three pharmacophore models were generated. Consequently, 14 hits were retrieved as final candidates by utilizing virtual screening of ZINC database and molecular docking. 相似文献
53.
Karimzadeh F Primeau M Mountassif D Rouiller I Lamarche-Vane N 《The Journal of biological chemistry》2012,287(23):19610-19621
The Rho family of small GTPases are membrane-associated molecular switches involved in the control of a wide range of cellular activities, including cell migration, adhesion, and proliferation. Cdc42 GTPase-activating protein (CdGAP) is a phosphoprotein showing GAP activity toward Rac1 and Cdc42. CdGAP activity is regulated in an adhesion-dependent manner and more recently, we have identified CdGAP as a novel molecular target in signaling and an essential component in the synergistic interaction between TGFβ and Neu/ErbB-2 signaling pathways in breast cancer cells. In this study, we identified a small polybasic region (PBR) preceding the RhoGAP domain that mediates specific binding to negatively charged phosphatidylinositol 3,4,5-trisphosphate (PI(3,4,5)P3). In vitro reconstitution of membrane vesicles loaded with prenylated Rac1 demonstrates that the PBR is required for full activation of CdGAP in the presence of PI(3,4,5)P3. In fibroblast cells, the expression of CdGAP protein mutants lacking an intact PBR shows a significant reduced ability of the protein mutants to induce cell rounding or to mediate negative effects on cell spreading. Furthermore, an intact PBR is required for CdGAP to inactivate Rac1 signaling into cells, whereas it is not essential in an in vitro context. Altogether, these studies reveal that specific interaction between negatively charged phospholipid PI(3,4,5)P3 and the stretch of polybasic residues preceding the RhoGAP domain regulates CdGAP activity in vivo and is required for its cellular functions. 相似文献
54.
Shamsipur M Miran Beigi AA Teymouri M Poursaberi T Mostafavi SM Soleimani P Chitsazian F Tash SA 《Biodegradation》2012,23(2):311-318
Methyl tert-butyl ether (MTBE) is widely used as gasoline oxygenate and octane number enhancer for more complete combustion
in order to reduce the air pollution caused by motor vehicle exhaust. The possible adverse effects of MTBE on human health
are of major public concern. However, information on the metabolism of MTBE in human tissues is scarce. The present study
demonstrates that human cytochrome P450 2A6 is able to metabolize MTBE to tert-butyl alcohol (TBA), a major circulating metabolite
and marker for exposure to MTBE. As CYP2A6 is known to be constitutively expressed in human livers, we infer that it may play
a significant role in metabolism of gasoline ethers in liver tissue. 相似文献
55.
Firoozeh F Zahraei-Salehi T Shahcheraghi F Karimi V Aslani MM 《FEMS immunology and medical microbiology》2012,64(2):237-243
A total of 84 Salmonella enterica serovar Enteritidis (S. Enteritidis) isolates, 42 of human and 42 of poultry origin, were characterized for antimicrobial resistance patterns and class I integrons. Among them, 58 (69%) S. Enteritidis were multidrug-resistant (MDR) and showed resistance to two or more antibiotic classes. By PCR assays and DNA sequencing, 50 (59.5%) S. Enteritidis isolates were found to carry class I integrons. Amplification of internal variable regions of class I integrons revealed five different arrays (0.75 kb only, 1 kb only, 1.3 kb only, both 1 and 1.2 kb, and both 1 and 1.3 kb). The integrons were further sequenced and the dfrA25 (0.75 kb), aadA1 (1 kb), aadA2 (1 kb), bla(PSE1) (1.2 kb) aadA6-orfD (1.3 kb) gene cassette arrays were identified. Ciprofloxacin minimum inhibitory concentration (MIC) values for the three isolates that showed resistance or reduced susceptibility via the disc diffusion method were 0.5-4 μg mL(-1), although only three isolates exhibited resistance to cefteriaxone (MIC: 128-256 μg mL(-1)) and four isolates were resistant to florfenicol (MIC: 32-128 μg mL(-1)). In conclusion, the high rates of multidrug-resistance and class I integrons found among S. Enteritidis isolates in humans and poultry in Tehran suggest that efforts are needed to confine the prevalence of MDR Salmonella isolates. 相似文献
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59.
Switoński M Godynicki S Jackowiak H Pieńkowska A Turczuk-Bierła I Szymaś J Goliński P Bereszyński A 《The Journal of heredity》2000,91(2):149-150
Three copies of the X chromosome were identified in a 5-year-old mixed breed infertile bitch. One year after the cytogenetic examination, the bitch died due to gastritis hemorrhagica, an inflammation of the mucus coat of the stomach. Dental studies showed congenital lack of some premolar and molar teeth. Ovaries were of normal shape and size. Also, histologic sections of the ovaries revealed their normal structure, with two corpora lutea and primary follicles. Phenotypic effects of X trisomy are discussed. 相似文献
60.
Eftekhar F Yousefzadi M Azizian D Sonboli A Salehi P 《Zeitschrift für Naturforschung. C, Journal of biosciences》2005,60(11-12):821-825
Antimicrobial activity of the essential oils obtained from leaves, root and the seeds of Diplotaenia damavandica Mozaffarian, Hedge & Lamond, an endemic plant to Iran, was determined against 10 microorganisms using the disk susceptibility test as well as measuring minimum inhibitory concentrations. The results showed that all three oils had antibacterial activity against Bacillus subtilis, Staphylococcus aureus, Staphylococcus epidermidis and Escherichia coli. The essential oil from the leaves had the highest antimicrobial activity against all test microorganisms including the fungal strains. The essential oils compositions were analyzed and determined by GC and GC-MS. The oils analyses resulted in the identification of 16, 17 and 20 compounds representing 94.2%, 96.4% and 95.1% of the total oils, respectively. The main components of the leaf essential oils were (Z)-beta-ocimene (21.6%), alpha-phellandrene (21.3%) and terpinolene (20%). Dill apiol (30.1%) and gamma-terpinene (16.2%) were the main components of the root and seed essential oils, respectively. 相似文献