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1.
Dokl Biol Sci ; 483(1): 231-234, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30603945

RESUMO

This is the first report on the finding of large intra-intestinal symbionts belonging to the order Eccrinida in crab-like decapod crustaceans of the family Lithodidae, Paralithodes camtschaticus and Lithodes maja, inhabiting the Barents Sea. Studies have been regularly conducted since the early 2000s in Kola Bay and in one of the inlets of the Eastern Murman Coast. Since 2005, Eccrinida representatives (presumably, a new species of the genus Arundinula) have been found in the guts of the red king crab. A brief description of the endosymbionts and data on their frequency of occurrence are presented. The possible reasons for the distribution of eccrinids in the crab-like decapod crustaceans of the Barents Sea are discussed.


Assuntos
Anomuros/anatomia & histologia , Trato Gastrointestinal/anatomia & histologia , Simbiose , Animais
2.
Dokl Biol Sci ; 463: 200-4, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26335970

RESUMO

In different habitats of the Kola Bay (Western Murman) and Dalnezelenetskaya and Yarnyshnaya bays (Eastern Murman), the size and structure of ecological rations (foraging of benthos) of the red king crab, which is an alien species in the Barents Sea, was established. The material for the study was collected in 2000-2009. In the Kola Bay, significant variability in time of this nutrition was detected for individuals of the same size category, which was associated with the depletion of food resources due to the high abundance of invaders in the area. The stable values of the ration and its structures in Eastern Murman bays indicated the prosperous state of benthic communities and an insignificant impact of crabs on these communities.


Assuntos
Crustáceos/fisiologia , Comportamento Alimentar/fisiologia , Cadeia Alimentar , Modelos Biológicos , Oceanos e Mares , Comportamento Predatório/fisiologia , Animais , Tamanho Corporal/fisiologia , Simulação por Computador , Crescimento Demográfico , Federação Russa
3.
Biofizika ; 60(1): 18-31, 2015.
Artigo em Russo | MEDLINE | ID: mdl-25868337

RESUMO

Methods of construction of support vector machines require no further a priori infoimation and provide big data processing, what is especially important for various problems in computational biology. The question of the quality of learning algorithms is considered. The main algorithms of support vector machines for binary classification are reviewed and they were comparatively explored for their efficiencies. The critical analysis of the results of this study revealed the most effective support-vector-classifiers. The description of the recommended algorithms, sufficient for their practical implementation, is presented.


Assuntos
Algoritmos , Modelos Teóricos , Máquina de Vetores de Suporte
4.
Biofizika ; 60(6): 1085-98, 2015.
Artigo em Russo | MEDLINE | ID: mdl-26841501

RESUMO

Methods of construction of support vector machines do not require additional a priori information and can be used to process large scale data set. It is especially important for various problems in computational biology. The main set of algorithms of support vector machines for regression is presented. The comparative efficiency of a number of support-vector-algorithms for regression is investigated. A thorough analysis of the study results found the most efficient support vector algorithms for regression. The description of the presented algorithms, sufficient for their practical implementation is given.


Assuntos
Algoritmos , Modelos Teóricos , Máquina de Vetores de Suporte , Biologia Computacional , Análise de Regressão
5.
Biofizika ; 59(3): 446-57, 2014.
Artigo em Russo | MEDLINE | ID: mdl-25715585

RESUMO

A new type of learning algorithms with the supervisor for estimating multidimensional functions is considered. These methods based on Support Vector Machines are widely used due to their ability to deal with high-dimensional and large datasets, and their flexibility in modeling diverse sources of data. Support vector machines and related kernel methods are extremely good at solving prediction problems in computational biology. A background about statistical learning theory and kernel feature spaces is given including practical and algorithmic considerations.


Assuntos
Interpretação Estatística de Dados , Modelos Teóricos , Análise de Regressão , Máquina de Vetores de Suporte
6.
Bioorg Khim ; 38(5): 555-68, 2012.
Artigo em Russo | MEDLINE | ID: mdl-23342489

RESUMO

1,2-Diol-oligoribonucleotides were prepared using fully protected 2'-O-[2-(2,3-dihydroxypropyl)amino-2-oxoethyl]uridine 3'-phosphoramidite. Incorporation of the 2'-modified uridine residue into oligonucleotide chains does not significantly affect the thermal stability of RNA and RNA-DNA duplexes. Periodate oxidation of the 1,2-diol results in reactive 2'-aldehyde oligoribonucleotides. Further application of these oligonucleotides for cross-linking with bacterial ribonuclease P was investigated.


Assuntos
Aldeídos/química , DNA/química , Ácidos Nucleicos Heteroduplexes/química , Oligorribonucleotídeos/química , Oligorribonucleotídeos/síntese química , RNA/química , Proteínas de Bactérias/química , Ribonuclease P/química
8.
Eksp Klin Farmakol ; 73(8): 14-6, 2010 Aug.
Artigo em Russo | MEDLINE | ID: mdl-20919551

RESUMO

Bizerine-oxalate of hexamethylene-bic-[N-methylcarbamic acid-3-(2-dimethylaminomethyl)pyridyl ether] exhibits the properties of acetylcholine esterase (AChE) inhibitor, being comparable in this respect in in vitro tests to aminostigmine. Bizerine is 2.5 and 6.7 times less active in these tests than proserine and distigmine, respectively, but it forms more stable complex with the enzyme. Bizerine is 10-80 times less toxic for laboratory mammals as compared to prozerine; it is 3-60 times more active on the isolated urinary bladder of rats, but it is 100-500 times less effective on the spinal muscle of leeches and skeletal muscles of mice and rats. Bizerine actively inhibits intestinal cholinesterase (ChE) of guinea pigs. In systematic use, it does not inhibit brain ChE of mice. Bizerine is a prolonged peripheral muscarinic potentiating inhibitor of ChE and activator of intestinal peristalsis.


Assuntos
Carbamatos/farmacologia , Inibidores da Colinesterase/farmacologia , Trato Gastrointestinal , Piridinas/farmacologia , Animais , Carbamatos/efeitos adversos , Gatos , Inibidores da Colinesterase/efeitos adversos , Cricetinae , Cães , Humanos , Camundongos , Neostigmina/efeitos adversos , Neostigmina/farmacologia , Piridinas/efeitos adversos , Brometo de Piridostigmina/efeitos adversos , Brometo de Piridostigmina/análogos & derivados , Brometo de Piridostigmina/farmacologia , Ratos
12.
Neurosci Behav Physiol ; 32(4): 363-7, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12243256

RESUMO

Cross- and autocorrelation histograms were constructed to investigate the linkage of spike activity from neurons in the right and left lateral hypothalamus, recorded in conditions of restful waking, after 24-h food deprivation, and after satiation. In conditions of hunger, there was a preferred order in which neurons fired in these two hypothalamic regions: a significant majority of cases (59%) showed initial firing by a neuron in the left hypothalamus followed by a neuron in the right, with delays of up to 200 msec and peaks in the delay plot at 30 and 160 msec. The opposite firing order was seen less frequently (21% of cases). In conditions of hunger, linked spike activity showed an increase in the probability of detecting frequencies in the theta range (from 11% to 29%).


Assuntos
Alimentos , Lateralidade Funcional/fisiologia , Região Hipotalâmica Lateral/fisiologia , Motivação , Neurônios/fisiologia , Animais , Eletrofisiologia , Fome/fisiologia , Região Hipotalâmica Lateral/citologia , Microeletrodos , Coelhos
13.
Vopr Med Khim ; 45(6): 525-9, 1999.
Artigo em Russo | MEDLINE | ID: mdl-10761219

RESUMO

A series of aminostigmin derivatives with various substituents at nitrogen in the second position of the pyridine ring, has been tested. The efficacy of preventing the death of mice poisoned by armine in five of the seven substances correlates with the constant of the rate of carbamylation of acetylcholinesterase in the in vitro experiments and with the hydrophobic nature. It is suggested that the phenomenon of protection of animals against the toxic effect of organophosphorous compounds involves the "leaving portion" of the molecule of carbamates.


Assuntos
Armina/toxicidade , Carbamatos/farmacologia , Inibidores da Colinesterase/farmacologia , Inibidores da Colinesterase/toxicidade , Intoxicação/prevenção & controle , Piridinas , Animais , Carbamatos/química , Inibidores da Colinesterase/química , Humanos , Masculino , Camundongos , Brometo de Piridostigmina/análogos & derivados , Relação Estrutura-Atividade
14.
Math Biosci ; 150(1): 63-82, 1998 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9654893

RESUMO

This paper considers the utility of a stochastic model of carcinogenesis proposed by Yakovlev and Polig [Math. Biosci. 132 (1996) 1-33] in the analysis of experimental data on multiple tumors induced by chemical carcinogens. The model provides a good description of published data on multiple tumors developing in the lungs of mice in response to different schedules of urethane. The distribution of pulmonary tumor counts appears to be negative binomial for each period of time after exposure to urethane. Our results suggest that the rate of administration of urethane has little effect both on the mean number of initiated cells per unit dose and on the rate of formation of lesions responsible for cell death. As our estimates show, more than 80% of initiated cells die in the course of tumor promotion. The model is robust to variations in the rate of urethane excretion given a fixed total dose of the carcinogen. Some prospects for further development of the model to allow for expansion of promoted cell clones are discussed.


Assuntos
Carcinógenos/efeitos adversos , Neoplasias Pulmonares/induzido quimicamente , Modelos Biológicos , Neoplasias Primárias Múltiplas/induzido quimicamente , Uretana/efeitos adversos , Animais , Distribuição Binomial , Carcinógenos/administração & dosagem , Carcinógenos/farmacocinética , Morte Celular/fisiologia , Intervalos de Confiança , Relação Dose-Resposta a Droga , Esquema de Medicação , Feminino , Funções Verossimilhança , Masculino , Camundongos , Processos Estocásticos , Fatores de Tempo , Uretana/administração & dosagem , Uretana/farmacocinética
15.
Ann N Y Acad Sci ; 837: 462-8, 1997 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-9472358

RESUMO

This paper discusses an application of the stochastic model of carcinogenesis proposed by Yakovlev and Polig to the analysis of experimental data on multiple pulmonary tumors induced by urethane. The results of this analysis suggest that the rate of administration of urethane has no effect on the mean number of initiated cells per unit dose. Likewise, the formation of lesions responsible for cell death appears to be unaffected by the dose rate.


Assuntos
Adenoma/induzido quimicamente , Neoplasias Pulmonares/induzido quimicamente , Neoplasias Experimentais/induzido quimicamente , Uretana/toxicidade , Animais , Modelos Animais de Doenças , Camundongos , Camundongos Endogâmicos A , Neoplasias Primárias Múltiplas/induzido quimicamente , Processos Estocásticos
16.
Eksp Klin Farmakol ; 57(5): 13-5, 1994.
Artigo em Russo | MEDLINE | ID: mdl-7696893

RESUMO

Experiments on non-inbred albino mice have demonstrated that aminostigmine is an active reversible centrally active cholinesterase inhibitor close to the properties of physostigmine, but greatly superior to it in its action duration. Clinical examinations of healthy volunteers and patients have shown that aminostigmine-induced inhibition of cholinesterase activity persists 6 hours. The agent have been found to be more highly effective in treating cholin blocker-induced intoxications than galanthamine, which manifests itself in its greater stability of the therapeutical effect achieved and in its higher ability to prevent cardiovascular events occurring in intoxication.


Assuntos
Carbamatos , Antagonistas Colinérgicos/intoxicação , Inibidores da Colinesterase/farmacologia , Inibidores da Colinesterase/uso terapêutico , Piridinas , Doença Aguda , Animais , Encéfalo/efeitos dos fármacos , Encéfalo/enzimologia , Colinesterases/efeitos dos fármacos , Avaliação de Medicamentos , Avaliação Pré-Clínica de Medicamentos , Hemólise/efeitos dos fármacos , Humanos , Técnicas In Vitro , Camundongos , Intoxicação/tratamento farmacológico , Brometo de Piridostigmina/análogos & derivados , Fatores de Tempo
17.
Radiobiologiia ; 32(6): 785-7, 1992.
Artigo em Russo | MEDLINE | ID: mdl-1494644

RESUMO

A generalized multihit-multitarget model for a nonhomogeneous, with respect to radiosensitivity, population of irradiated cells is presented. The least squares and the maximum likelihood estimation of the model parameters is given. The estimates quality is evaluated by the computer-based study. The results obtained show the possibility of the parametric identification of cell radiosensitivity distribution according to the "dose-response" data.


Assuntos
Células/efeitos da radiação , Relação Dose-Resposta à Radiação , Modelos Biológicos , Doses de Radiação , Software
18.
Eksp Klin Farmakol ; 55(1): 13-6, 1992.
Artigo em Russo | MEDLINE | ID: mdl-1305425

RESUMO

The pharmacological properties of a new drug approved in the USSR for the treatment of cholinolytics poisonings are described. The drug is as active as physostigmine. However, its action is longer. Aminostigmine exhibits marked central effects, which forms the basis for its use for elimination of brain dysfunctions caused by choline blockers.


Assuntos
Carbamatos , Inibidores da Colinesterase/farmacologia , Piridinas , Músculos Abdominais/efeitos dos fármacos , Animais , Encéfalo/efeitos dos fármacos , Encéfalo/enzimologia , Gatos , Inibidores da Colinesterase/toxicidade , Colinesterases/sangue , Cães , Cobaias , Técnicas In Vitro , Camundongos , Fisostigmina/farmacologia , Brometo de Piridostigmina/análogos & derivados , Coelhos , Ranidae , Ratos , Bexiga Urinária/efeitos dos fármacos
19.
Pediatriia ; (2): 37-40, 1991.
Artigo em Russo | MEDLINE | ID: mdl-2057289

RESUMO

Overall 69 girls with stage II and III juvenile hyperplasia of the thyroid without any clinical signs of pubertal abnormality were examined. Of these, 2/3 had the normal content of circulating thyroid and thyrotropic hormones in the blood serum. In prepubertal girls, the age-associated basal concentrations of gonadotropins and sexual steroid were discovered, whereas in puberty, there was a significant increase of the content of luteinizing hormone, prolactin, estradiol (a two-fold increase) and progesterone (a ten-fold increase) in the second phase of the menstrual cycle, which attested to its ovulatory nature. In 1/3 of the girls, subclinical hypothyrosis with a significant rise of the level of thyrotropic hormone associated with normal or lowered concentrations of triiodothyronine or thyroxine was diagnosed. In addition, the metabolic markers of the discoordination of the hypothalamo-hypophyseal-gonadal system were revealed: an increase of the content of luteinizing hormone and prolactin associated with the low levels of estradiol and progesterone.


Assuntos
Bócio/fisiopatologia , Puberdade/fisiologia , Maturidade Sexual/fisiologia , Glândula Tireoide/fisiopatologia , Adolescente , Criança , Feminino , Bócio/patologia , Hormônios Esteroides Gonadais/sangue , Humanos , Hiperplasia , Hormônios Adeno-Hipofisários/sangue , Glândula Tireoide/patologia , Hormônios Tireóideos/sangue
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