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1.
Vavilovskii Zhurnal Genet Selektsii ; 25(7): 693-700, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34950841

RESUMO

Vitis rotundifolia Michx. is one of the species of the family Vitaceae, with resistance to both biotic and abiotic stresses. The present study reports new scientif ic knowledge about the inheritance of resistance to downy mildew, powdery mildew and frost by V. vinifera varieties from V. rotundifolia. Recombinant lines of three hybrid populations from the crossing of the maternal genotype ♀M. 31-77-10 with V. rotundifolia hybrids were used as the object of the study. As a result of laboratory screening, more than 40 % of recombinants of the ♀M. 31-77-10 × × [DRX-M5-734 + DRX-M5-753 + DRX-M5-790] population showed a high degree of frost resistance (-24 °C), while 6 % of transgressive recombinants were characterized by a very high degree of resistance (-27 °Ð¡). The maternal genotype ♀M. 31-77-10 does not carry alleles of resistance to powdery mildew at the Run1 locus and in the f ield suffers from powdery mildew much more than the paternal genotypes. The prevalence of powdery mildew on vegetative organs in the three recombinant populations over the years varies on average between 3.2-17.1, 0.3-17.7 and 0.6-5.2 %, respectively. As a result, almost all recombinant genotypes that received a resistant allele from the paternal genome are highly resistant to powdery mildew.

2.
Adv Gerontol ; 32(1-2): 121-127, 2019.
Artigo em Russo | MEDLINE | ID: mdl-31228377

RESUMO

The course intake of the nutritional supplement «Kardisten¼ normalizes increased levels of cortisol in the blood, optimizes the activity of the vessels of the brain, improving the functional state and leading to an increase in the productivity of short-term and long-term memory, more pronounced in the group of persons up to 50. At initial organic changes in the brain vessels, «Kardisten¼ significantly reduces the level of cortisol, increases to a greater extent the productivity of memory than at atherosclerosis. «Kardisten¼ activates the natural mechanisms of increasing the functional capabilities of an organism, exerting a beneficial effect on the body of adults and the elderly people, and can be recommended for the correction of physical, mental health and preservation of active longevity.


Assuntos
Transtornos da Memória , Memória , Saúde Mental , Extratos Vegetais , Adulto , Idoso , Encéfalo/efeitos dos fármacos , Humanos , Hidrocortisona , Longevidade , Transtornos da Memória/tratamento farmacológico , Extratos Vegetais/uso terapêutico
3.
Nanoscale ; 10(30): 14499-14509, 2018 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-30024005

RESUMO

The morphology and electronic properties of single and few-layer graphene films nanostructured by the impact of heavy high-energy ions have been studied. It is found that ion irradiation leads to the formation of nano-sized pores, or antidots, with sizes ranging from 20 to 60 nm, in the upper one or two layers. The sizes of the pores proved to be roughly independent of the energy of the ions, whereas the areal density of the pores increased with the ion dose. With increasing ion energy (>70 MeV), a profound reduction in the concentration of structural defects (by a factor of 2-5), relatively high mobility values of charge carriers (700-1200 cm2 V-1 s-1) and a transport band gap of about 50 meV were observed in the nanostructured films. The experimental data were rationalized through atomistic simulations of ion impact onto few-layer graphene structures with a thickness matching the experimental samples. We showed that even a single Xe atom with energy in the experimental range produces a considerable amount of damage in the graphene lattice, whereas high dose ion irradiation allows one to propose a high probability of consecutive impacts of several ions onto an area already amorphized by the previous ions, which increases the average radius of the pore to match the experimental results. We also found that the formation of "welded" sheets due to interlayer covalent bonds at the edges and, hence, defect-free antidot arrays is likely at high ion energies (above 70 MeV).

4.
Eksp Klin Gastroenterol ; (3): 74-82, 2015.
Artigo em Russo | MEDLINE | ID: mdl-26281181

RESUMO

UNLABELLED: The aim of this work was to assess the potential of some physical and chemical methods for studying erythrocytes and blood serum in gastroenterological practice by the example of colorectal cancer (CC). MATERIALS AND METHODS: A total of 26 persons with various stages of colorectal cancer and 16 healthy (control group) were examined. Parameters of erythrocytes and blood serum were investigated by light microscopy, dielectrophoresis in a non-uniform alternating electric field (DEF in NUAEF), terahertz spectroscopy, ellipsometry, Raman-spectroscopy. RESULTS: Polymorphism of erythrocytes, rigidity, viscosity, indexes of aggregation and destruction were significantly higher in patients with CC and polarizability, amplitude of erythrocyte deformation in NUAEF being lower than those in the controls. The study of erythrocytes by terahertz spectroscopy revealed the low levels of amplitude transmittance over the whole frequency range in CC patients compared to the controls. The increasing of refractive index, degree of heterogeneity of thin films obtained from the serum in CC patients were observed in considering the ellipsometric parameters. We found a significant increasing of the concentration of antigens to CD24 at the early stage of the disease. The areas of some peaks in Raman spectra were significantly lower in patients with CC compared to the healthy ones, it is possible due to a carotin deficiency. Most of the studied parameters were correlated with the stage of the disease. A set of optical methods for studying blood serum compared with those of histology and radiological methods of diagnosis showed their high sensitivity and specificity, positive and negative predictive value (80 % and above). CONCLUSION: The obtained results of the pilot study demonstrate the prospects of using physical and chemical methods of research of erythrocytes and blood serum for early diagnosis, stage of disease and monitoring the effectiveness of treatment of CC.


Assuntos
Análise Química do Sangue/métodos , Neoplasias Colorretais/sangue , Neoplasias Colorretais/diagnóstico , Eritrócitos/metabolismo , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Valor Preditivo dos Testes
5.
Radiats Biol Radioecol ; 55(1): 43-50, 2015.
Artigo em Russo | MEDLINE | ID: mdl-25962275

RESUMO

Comparison of action of chronic γ-irradiation at a dose of 22.6 cGy and the serpisten substance containing phitoecdysteroids at small doses of 5 and 50 mg/kg on biochemical indicators in erythrocytes and tissues of white not purebred mice is given. It is established that in both cases there is an increase of minor fractions of cardiolipin and phosphatidic acid, lysophosphatidilcholin and a share of phospholipids as part of common lipids. Course administration of serpisten to rats at the total doses of 12 and 30 mg/kg leads to an increase in tissues of thermal shock proteins of family 70 (Hsp70 and Hsc70). Similarity of action of ecdysteroid preparations and the influence of stress factors of physical nature of low intensity (gamma radiation at a small dose) have been detected in mice, which manifest themselves in some chain links of lipid peroxidation processes as well as an increase in biosynthesis of thermal shock proteins of family 70 (Hsp70 and Hsc70) in rats at administration of serpisten.


Assuntos
Ecdisteroides/administração & dosagem , Raios gama , Proteínas de Choque Térmico HSP70/biossíntese , Peroxidação de Lipídeos/genética , Adaptação Fisiológica/efeitos da radiação , Animais , Relação Dose-Resposta à Radiação , Eritrócitos/efeitos dos fármacos , Eritrócitos/efeitos da radiação , Regulação da Expressão Gênica/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos da radiação , Proteínas de Choque Térmico HSP70/genética , Peroxidação de Lipídeos/efeitos dos fármacos , Peroxidação de Lipídeos/efeitos da radiação , Camundongos , Fosfolipídeos/metabolismo , Ratos
6.
Bull Exp Biol Med ; 158(1): 4-8, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25403385

RESUMO

Experiments on rats were performed to study the process of operant feeding learning, locomotor activity, oxygen consumption, and concentrations of corticosterone, ß-endorphin, and prostaglandin E in blood serum after dietary treatment with the phytoecdysteroid extract. Administration of phytoecdysteroids was followed by the improvement of learning and increase in oxygen consumption and locomotor activity. Locomotor activity and oxygen consumption in the majority of control rats and phytoecdysteroid-treated animals were shown to be interrelated with the total locomotor activity and goal-directed operant behavior, respectively. No significant differences were found in the concentration of hormones in blood serum from animals of the control and treatment groups.


Assuntos
Condicionamento Operante/efeitos dos fármacos , Ecdisteroides/administração & dosagem , Comportamento Alimentar/efeitos dos fármacos , Extratos Vegetais/administração & dosagem , Administração Oral , Animais , Asteraceae/química , Aprendizagem , Masculino , Atividade Motora , Consumo de Oxigênio , Ratos Wistar
7.
Vopr Pitan ; 83(2): 16-21, 2014.
Artigo em Russo | MEDLINE | ID: mdl-25059064

RESUMO

The impact of the 15-day consumption of Serratula coronata extract containing phytoecdysteroids on some indicators of hormonal status and activity of apoptosis in various organs of growing male Wistar rats (initial body weight 127.8 +/-2.5 sigma) has been studied. The extract from the leaves of Serratula coronata was added to the water of animals of experimental groups 2 and 3 (n = 8 in each group) daily at the dose of 5 and 15 mg phytoecdysteroids per kg of body weight respectively. Animals of the control group 1 (n = 8) received water alone throughout the experiment. Daily volume of drunk fluid was recorded. At the 15th day of the experiment animals were taken out using the decapitation under the light ether anesthesia. The content of corticosterone, prostaglandin E2 and beta-endorphin in rat blood plasma were determined by ELISA test. Plasma level of noradrenaline was determined by HPLC. DNA damage and percentage of apoptotic cells (apoptotic index) were measured in isolated cells of the thymus, heart and brain by single-cell gel electrophoresis (the comet assay). Significantly lower concentration of norepinephrine was detected in plasma of experimental animals from groups 2 and 3 (10.3 +/- 1.1 and 7.2 +/- 0.8 ng/ml, respectively) compared to the same index in the control group (20.4 +/- 3.4 ng/ml). Significant differences of other biochemical parameters for all groups of animals have not been identified. Statistical significant difference in the ratio of corticosterone/norepinephrine compared with control animals was detected for a group of rats consumed the highest dose of phytoecdysteroids. There was no statistically significant difference in DNA fragmentation and apoptosis index in animals consumed phytoecdysteroids in compare with the control group of animals. The absence of the activity of apoptosis in cells of the heart, brain and thymus of rats treated with phytoecdysteroid extract may indicate the safety of its use in the diet of the animals.


Assuntos
Apoptose/efeitos dos fármacos , Asteraceae/química , Corticosterona/sangue , Dinoprostona/sangue , Ecdisteroides/farmacologia , Norepinefrina/sangue , Extratos Vegetais/farmacologia , beta-Endorfina/sangue , Animais , Fragmentação do DNA/efeitos dos fármacos , Ecdisteroides/química , Masculino , Extratos Vegetais/química , Ratos , Ratos Wistar
8.
Vopr Pitan ; 82(4): 22-6, 2013.
Artigo em Russo | MEDLINE | ID: mdl-24340928

RESUMO

The experiment in vivo in growing male Wistar rats was carried out. The animals of the experimental 2-4 groups were daily intragastrically injected water solutions of the dried extract from the leaves of Seratulla coronata L. in volume of 1.0 ml, containing 2, 20 and 50 mg of phytoecdysteroids per kg of animal weight, accordingly. Animals of control group were daily injected 1.0 ml of water. The content of phytoecdysteroids in the dry extract was analyzed by high performance liquid chromatography (HPLC). The concentration of the sum of phytoecdysteroids in dry extract was 6.15%, 66% of which was 20-hydroxyecdysone and 23% was 25S-inokosteron. On the 15th day animals were taken out of the experiment by the decapitation. The content of corticosterone, prostaglandin E2 and beta-endorphin in rat blood plasma were determined by ELISA test. The pathological--anatomical analysis and weighing of the liver did not reveal any adverse changes of this organ in the animals of all groups. The average concentration of blood plasma corticosterone reduced with increasing of the dose of the extract injected to the animals, reaching significant differences relative to the control group (60.9 +/- 9.4 ng/ml) for 3 and 4 groups (22.7 +/- 6.6 and 17.6 +/- 7.3 ng/ml, accordingly). Beta-endorphin and prostaglandin E2 levels did not differ. The ratio of the mediator of stress (corticosterone) and inhibitors of stress (beta-endorphin and prostaglandin E2) has been calculated. A monotonic decrease of corticosterone/beta-endorphin and corticosterone/prostaglandin E2 ratio has been found with extract dose increasing. Taken together the results of determination of biochemical parameters of the general adaptation syndrome the dose-dependent stress-protective effect of Seratulla coronata L extract has been demonstrated.


Assuntos
Colestenos/farmacologia , Corticosterona/sangue , Dinoprostona/sangue , Ecdisterona/farmacologia , Fitosteróis/farmacologia , beta-Endorfina/sangue , Animais , Fígado/metabolismo , Masculino , Extratos Vegetais/farmacologia , Ratos
9.
Vopr Pitan ; 82(6): 24-30, 2013.
Artigo em Russo | MEDLINE | ID: mdl-24741953

RESUMO

In the review the presentation about plant adaptogens--biologically active compounds is given. Its administration can help to achieve non-specific state of high resistance. The hypothetical mechanism of action: adaptogens are prostressors, reducing excessive increase of stress mediators in the following stress exposure. The features of adaptogenic effect of phytoecdysteroids, polyhydroxylated sterols, which are analogs of hormones of molting and metamorphosis of arthropodas, and are structurally similar to glucocorticoids on the example of the most widely studied phytoecdysteroid--20-hydroxyecdysone--are described. The results of studies of anabolic action of 20-hydroxyecdysone in experiments on laboratory animals and the possible explanation (existing in the modern scientific literature) of the mechanism of this phenomenon are discussed. Scientific publication testifying on the application of phytoecdysteroids to remove chronic fatigue syndrome, reducing nerve and muscle fatigue, improve memory and attention processes are presented. The prospects of using the 20-hydroxyecdysone in the composition of food supplements and specialized products for athletes are discussed.


Assuntos
Adaptação Fisiológica/efeitos dos fármacos , Anabolizantes/farmacologia , Ecdisterona/farmacologia , Compostos Fitoquímicos/farmacologia , Fenômenos Fisiológicos da Nutrição Esportiva , Ciências da Nutrição e do Esporte , Anabolizantes/isolamento & purificação , Anabolizantes/toxicidade , Animais , Ecdisterona/isolamento & purificação , Ecdisterona/toxicidade , Humanos , Dose Letal Mediana , Compostos Fitoquímicos/isolamento & purificação , Compostos Fitoquímicos/toxicidade
10.
J Nanosci Nanotechnol ; 12(11): 8694-9, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23421268

RESUMO

The SiO(x) films of various stoichiometries deposited on Si substrates with the use of the co-sputtering from two separate Si and SiO2 targets were annealed by femtosecond laser pulses. Femtosecond laser treatments were applied for crystallization of amorphous silicon nanoclusters in the silicon-rich oxide films. The treatments were carried out with the use of Ti-Sapphire laser with wavelength 800 nm and pulse duration about 30 fs. Regimes of crystallization of amorphous Si nanoclusters in the initial films were found. Ablation thresholds for SiO(x) films of various stoichiometries were discovered. The effect of laser assisted formation of a-Si nanoclusters in the non-stoichiometric dielectric films with relatively low concentration of additional Si atoms was also observed. This approach is applicable for the creation of dielectric films with semiconductor nanoclusters on non-refractory substrates.


Assuntos
Cristalização/métodos , Lasers , Membranas Artificiais , Nanoestruturas/química , Nanoestruturas/ultraestrutura , Dióxido de Silício/química , Silício/química , Dureza , Temperatura Alta , Teste de Materiais , Conformação Molecular/efeitos da radiação , Nanoestruturas/efeitos da radiação , Tamanho da Partícula , Silício/efeitos da radiação , Dióxido de Silício/efeitos da radiação , Propriedades de Superfície/efeitos da radiação
11.
Nanotechnology ; 22(28): 285502, 2011 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-21636883

RESUMO

Extremely high gas sensing properties of p-type few layer graphene flakes exfoliated from highly oriented pyrolytic graphite have been demonstrated. The current response to ammonia adsorption is strongly dependent on film thickness and is higher than that for graphene by 1-8 orders of magnitude. A maximal response was found for sample thickness ∼ 2 nm. The effect is attributed to the formation of multiple p-n-p junctions at the grain boundaries in the polycrystalline graphene flakes exposed to ammonia-containing ambient.

12.
Nanotechnology ; 20(9): 095205, 2009 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-19417483

RESUMO

We have followed the effects of heavy ion irradiation on the structural, electrical, and photoluminescence properties of ensembles of silicon nanocrystallites embedded in a dielectric (SiO(2)) matrix. This was done as a function of the irradiation dose and the content of the Si phase. The results obtained can be accounted for self-consistently assuming that a relatively small dose of the irradiation enhances the crystallization while for higher doses the irradiation enhances the amorphization. The corresponding processes suggest that tuning of the above properties can be achieved by swift heavy ion irradiation.


Assuntos
Cristalização/métodos , Nanoestruturas/química , Nanoestruturas/ultraestrutura , Nanotecnologia/métodos , Dióxido de Silício/química , Íons Pesados , Medições Luminescentes , Substâncias Macromoleculares/química , Substâncias Macromoleculares/efeitos da radiação , Teste de Materiais , Conformação Molecular/efeitos da radiação , Nanoestruturas/efeitos da radiação , Tamanho da Partícula , Doses de Radiação , Dióxido de Silício/efeitos da radiação , Propriedades de Superfície/efeitos da radiação
13.
Nanotechnology ; 19(24): 245302, 2008 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-21825807

RESUMO

Decomposition of germanium monoxide (GeO) films under the impact of an atomic force microscope (AFM) tip was observed for the first time. It is known that GeO is metastable in the solid phase and decomposes into Ge and GeO(2) under thermal annealing or radiation impact. AFM tip treatments allow us to carry out local decomposition. A novel tip-induced local electrical decomposition (TILED) method of metastable GeO films has been developed. Using TILED of 10 nm thin GeO film, Ge nanowires on silicon substrates were obtained.

15.
Eksp Klin Farmakol ; 69(6): 9-12, 2006.
Artigo em Russo | MEDLINE | ID: mdl-17209455

RESUMO

Changes of the transmembrane potassium, calcium, and sodium ion currents in isolated neurons of Lymnaea stagnalis snail under the action of ecdysteroid fraction (serpisten) from Serratula coronata L. applied from outside in 0.01 -1000 microg/ml concentrations have been studied using the voltage-clamp technique. It is established for the first time that serpisten non-selectively activates the potassium and calcium ion currents (the currents amplitude increases by 2 - 15%) and reduces nonspecific membrane leakage currents in the entire range of concentrations. The sodium ion current also increased by 4 - 7% under the action of Serpisten in low concentrations (0.01 -10 microg/ml) in comparison with control, but this current decreased by 5 -10% at serpisten concentrations of 100 and 1000 microg/ml. The effects were reversible. The kinetics of currents was not changed under the action of serpisten.


Assuntos
Asteraceae/química , Ecdisteroides/farmacologia , Potenciais da Membrana/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Animais , Cálcio/metabolismo , Cátions/metabolismo , Ecdisteroides/isolamento & purificação , Técnicas In Vitro , Lymnaea/citologia , Neurônios/metabolismo , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/farmacologia , Potássio/metabolismo , Sódio/metabolismo
17.
Nanotechnology ; 17(18): 4743-7, 2006 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-21727607

RESUMO

The effect of Ge deposition rate on the morphology and structural properties of self-assembled Ge/Si(001) islands was studied. Ge/Si(001) layers were grown by solid-source molecular-beam epitaxy at 500 °C. We adjusted the Ge coverage, 6 monolayers (ML), and varied the Ge growth rate by a factor of 100, R = 0.02-2 ML s(-1), to produce films consisting of hut-shaped Ge islands. The samples were characterized by scanning tunnelling microscopy, Raman spectroscopy, and Rutherford backscattering measurements. The mean lateral size of Ge nanoclusters decreases from 14.1 nm at R = 0.02 ML s(-1) to 9.8 nm at R = 2 ML s(-1). The normalized width of the size distribution shows non-monotonic behaviour as a function of R and has a minimum value of 19% at R = 2 ML s(-1). Ge nanoclusters fabricated at the highest deposition rate demonstrate the best structural quality and the highest Ge content (∼0.9).

19.
Arch Insect Biochem Physiol ; 41(3): 156-61, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10398339

RESUMO

20-hydroxyecdysone (1 microM) was found to activate in vitro T-cell CD2 presentation, which is suppressed both in secondary immunodeficient persons and pharmacologically by increasing intracellular cAMP levels. The compound was found to act like a synthetic psycho-immunomodulator 1-oxy-4-oxoadamantane (1 microM) and to exceed the effects of the thymomimetic agent levamisol (1 microM). In addition, 20-hydroxyecdysone (1 microM) was also revealed to modulate the fluoride-stimulated respiratory burst of human neutrophils in the same manner as water soluble antioxidants. Arch.


Assuntos
Adjuvantes Imunológicos/farmacologia , Ecdisterona/farmacologia , Neutrófilos/efeitos dos fármacos , Linfócitos T/efeitos dos fármacos , Adjuvantes Imunológicos/química , Antígenos CD2/biossíntese , Ecdisterona/química , Humanos , Técnicas In Vitro , Estrutura Molecular , Neutrófilos/imunologia , Linfócitos T/imunologia
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