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101.
Oxidative stress plays numerous biological roles, both functional and pathological. The role of oxidative stress in various epidemiologically relevant biological traits in Anopheles mosquitoes is not well established. In this study, the effects of oxidative stress on the longevity and insecticide resistance phenotype in the major malaria vector species An. arabiensis and An. funestus were examined. Responses to dietary copper sulphate and hydrogen peroxide were used as proxies for the oxidative stress phenotype by determining the effect of copper on longevity and hydrogen peroxide lethal dose. Glutathione peroxidase and catalase activities were determined colorimetrically. Oxidative burden was quantified as protein carbonyl content. Changes in insecticide resistance phenotype were monitored by WHO bioassay. Insecticide resistant individuals showed an increased capacity for coping with oxidative stress, mediated by increased glutathione peroxidase and catalase activity. This effect was observed in both species, as well as in laboratory strains and F1 individuals derived from wild-caught An. funestus mothers. Phenotypic capacity for coping with oxidative stress was greatest in strains with elevated Cytochrome P450 activity. Synergism of oxidative stress defence enzymes by dietary supplementation with haematin, 3-Amino-1, 2, 4-triazole and Sodium diethyldithiocarbamate significantly increased pyrethroid-induced mortality in An. arabiensis and An. funestus. It is therefore concluded that defence against oxidative stress underlies the augmentation of the insecticide resistance phenotype associated with multiple blood-feeding. This is because multiple blood-feeding ultimately leads to a reduction of oxidative stress in insecticide resistant females, and also reduces the oxidative burden induced by DDT and pyrethroids, by inducing increased glutathione peroxidase activity. This study highlights the importance of oxidative stress in the longevity and insecticide resistance phenotype in malaria vectors. 相似文献
102.
O. M. Zherelova A. A. Kataev V. M. Grischenko R. Sh. Shtanchaev 《Cell and Tissue Biology》2016,10(6):476-485
The effects of haloperidol, an antagonist of D2 dopamine receptors, on the functioning of Ca2+, K+, and Cl? ion channels in the membrane of Chara corallina cells and on the functional properties of their cytoskeleton was studied. Haloperidol blocked Ca2+ channels of the plasmalemma. In addition to bringing about a decrease in the amplitude of the calcium current, exposure to haloperidol decelerated the activation and inactivation of calcium channels. The effect of haloperidol was reversible; after it was removed, the characteristics of calcium current were restored. Haloperidol did not affect Ca2+-activated chloride channels. Haloperidol also inhibited microfilament-dependent motion of the cytoplasm. Cytoplasmic streaming was restored after haloperidol was removed from the extracellular solution. These results suggest that the concentration of free Ca2+ ions in the cytoplasm increases in the presence of haloperidol, and that Ca2+ channels of C. corallina plasmalemma possess specific binding sites both for dopamine receptors and for their antagonists. 相似文献
103.
Production of biosurfactants by acidophilic mycobacteria was demonstrated in the course of aerobic degradation of hydrocarbons (n-tridecane, n-tricosane, n-hexacosane, model mixtures of С14–С17, С12?С19, and С9–С21n-alkanes, 2,2,4,4,6,8,8-heptamethylnonane, squalane, and butylcyclohexane) and their complex mixtures (hydrocarbon gas condensate, kerosene, black oil, and paraffin oil) under extremely acidic conditions (pH 2.5). When grown on hydrocarbons, the studied bacterial culture AGS10 caused a decrease in the surface and interfacial tension of the solutions (to the lowest observed values of 26.0 and 1.3 mN/m, respectively) compared to the bacteria-free control. The rheological characteristics of the culture changed only when mycobacteria were grown on hydrocarbons. Neither the medium nor the cell-free culture liquid had the surfactant activity, which indicated formation of an endotype biosurfactant by mycobacteria. Biodegradation of n-alkanes was accompanied by an increase in cell numbers, surfactant production, and changes in the hydrophobicity of bacterial cell surface and in associated phenomena of adsorption and desorption to the hydrocarbon phase. Research on AGS10 culture liquids containing the raw biosurfactant demonstrated the preservation of its activity within a broad range of pH, temperature, and salinity. 相似文献
104.
105.
D. Sh. Avzaletdinova L. F. Sharipova O. V. Kochetova T. V. Morugova V. V. Erdman O. E. Mustafina 《Russian Journal of Genetics》2016,52(8):877-881
The association of the variable rs1801282 locus of the PPARG2 gene (peroxisome proliferator-activated receptor gamma) with type 2 diabetes mellitus and its complications was analyzed in inhabitants of the Republic of Bashkortostan. The genotype frequencies of the variable rs1801282 locus of the PPARG2 gene did not significantly differ in groups of healthy persons and patients with type 2 diabetes in all three considered inheritance models (codominant, dominant, and recessive). At the same time, it was demonstrated that the risk of one of the diabetic complications, i.e., diabetic nephropathy, was associated with the variable rs1801282 locus of the PPARG2 gene. Diabetic nephropathy was more common in patients with the C/C genotype (62.7%) compared to the C/G and G/G genotypes (37.5%), P = 0.036. The G allele is protective in regard to diabetic nephropathy (OR = 0.36) in patients with type 2 diabetes mellitus. 相似文献
106.
Plasma Physics Reports - Based on the 16-moment MHD transport equations, the propagation of linear waves in an anisotropic homogeneous cosmic plasma is considered. A general dispersion relation is... 相似文献
107.
Yu. S. Babayan A. Sh. Markaryan V. P. Kalantaryan R. S. Kazaryan M. A. Parsadanyan P. O. Vardevanyan 《Biophysics》2007,52(2):259-260
DNA isolated from liver of healthy and tumor-bearing (sarcoma 45) rats was irradiated in water-salt solution with weak microwaves (64.5 GHz, 50 μW/cm2). The heat stability of DNA increased with irradiation time (a raise of 1.5°C in T m for “tumor” DNA after 90 min, without changes in ΔT), which may be associated with dehydration of the surrounding Na+ ions. 相似文献
108.
Molecular Biology - The protein synthesis in cells occurs in ribosomes, with the involvement of protein translational factors. One of these translational factors is the elongation factor P (EF-P).... 相似文献
109.
Belyanko T. I. Feoktistova E. S. Skrypina N. A. Skamrov A. V. Gurskii Ya. G. Rutkevich N. M. Dobrynina N. I. Bibilashvilli R. Sh. Savochkina L. P. 《Biophysics》2019,64(3):331-338
Biophysics - Abstract—Variants of miniplasminogen with an altered primary structure have been designed to study previously described changes in tryptophan fluorescence during plasminogen... 相似文献
110.