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1.
Bull Exp Biol Med ; 2024 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-39259466

RESUMO

The dynamics of nephropathy development in rats with type 2 diabetes mellitus, caused by a high-fat diet and the streptozotocin administration (25 mg/kg), and metabolic syndrome, caused by addition of 20% fructose solution to the diet, was evaluated during the experiment. Models with moderate severity of metabolic changes without significant changes in body weight were obtained after 24 weeks. To study neuropathy severity, the method of electroneuromyography was used; the velocities of motor and sensory excitation propagation along the caudal nerve fibers were measured. In modeled diabetes mellitus against the background of hyperglycemia, a marked decrease in motor and sensory propagation rates was observed, and an increase in the response durations was noted from week 12 to week 24, indicating pronounced neuropathy. In the fructose model, the motor response duration increased from week 12, which possibly indicates the development of peripheral neuropathy.

2.
Bull Exp Biol Med ; 177(3): 395-400, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39134815

RESUMO

We compared 2 models of metabolic syndrome in rats: high-fat diet (58% calories) with single streptozotocin injection at a dose of 25 mg/kg and replacement of water with 20% fructose solution. The model with fructose solution did not cause the main signs of metabolic syndrome over 24 weeks: concentrations of glucose, triglycerides, cholesterol, weight, and BP did not significantly differ from the control group (standard diet). At the same time, single streptozotocin administration was followed by the development of persistent hyperglycemia, hypertriglyceridemia, hypercholesterolemia, and signs of visceral obesity. High-fat diet combined with injection of streptozotocin in a low dose can be considered a more representative model of metabolic syndrome in humans.


Assuntos
Glicemia , Dieta Hiperlipídica , Síndrome Metabólica , Estreptozocina , Triglicerídeos , Animais , Dieta Hiperlipídica/efeitos adversos , Ratos , Masculino , Síndrome Metabólica/metabolismo , Triglicerídeos/sangue , Triglicerídeos/metabolismo , Glicemia/metabolismo , Ratos Wistar , Hiperglicemia/metabolismo , Hiperglicemia/induzido quimicamente , Colesterol/sangue , Colesterol/metabolismo , Peso Corporal/efeitos dos fármacos , Frutose/administração & dosagem , Hipertrigliceridemia/metabolismo , Hipertrigliceridemia/induzido quimicamente , Hipertrigliceridemia/sangue , Hipertrigliceridemia/etiologia , Hipercolesterolemia/metabolismo , Hipercolesterolemia/etiologia , Carboidratos da Dieta/administração & dosagem , Pressão Sanguínea/efeitos dos fármacos
3.
Balkan J Med Genet ; 23(2): 41-48, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33816071

RESUMO

Propofol (2,6-diisopropylphenol) is the most common intravenous anesthetic used in modern medicine. It is postulated that individual differences in genetic factors [polymorphism of single nucleotide polymorphisms (SNPs)] in the genes encoding metabolic enzymes, molecular targets and molecular binding sites of propofol can be responsible for susceptibility to propofol effects. The aim of our study was to investigate the influence of the cytochrome P450 2B6 isozyme CYP2B6 (rs3745274), γ-aminobutyric acid type A (GABAA) receptor α1 subunit GABRA1 (rs2279020) and ATP-binding cassette subfamily B member 1 ABCB1 (rs1045642) gene polymorphisms on propofol therapeutic outcomes in the patients undergoing abdominal hysterectomy. Ninety patients aged 29-74 years, with different ethnicities were included in this study. The presence of polymorphisms was analyzed using TaqMan SNP genotype analysis on Stratagene MxPro 3005P real-time polymerase chain reaction (qPCR). The distribution of all three genetic variants was within the Hardy-Weinberg equilibrium. There was no significant difference (p >0.05) in the allelic frequencies of polymorphic variants and genotype distributions between adult and older patients and between patients of different ethnicities. Our study did not detect a statistically significant influence of the CYP2B6 (c.516G>A), GABRA1 (c.1059+15G>A) and ABCB1 (c.3435T>C) variants on the variability of clinical parameters (doses for induction in anesthesia, additional doses, induction time and wake time after anesthesia and side effects of propofol). However, the observed trend on the possible influence of the CYP2B6 (c.516G>A) and GABRA1 (c.1059+15G>A) variants warrant an extension of these studies on a larger number of patients.

4.
Zh Vopr Neirokhir Im N N Burdenko ; 84(2): 103-109, 2020.
Artigo em Russo | MEDLINE | ID: mdl-32412199

RESUMO

The purpose of the review was to determine the capabilities of neurophysiological examination for predicting the outcome of spinal injury. We have analyzed the methods of neurophysiological examination of spinal cord function and the role of these data in prediction of functional recovery in patients with complicated vertebral-spinal injury. Application of functional diagnostic methods for spinal shock was also considered.


Assuntos
Traumatismos da Medula Espinal/diagnóstico , Neoplasias da Medula Espinal , Potencial Evocado Motor , Humanos , Medula Espinal , Coluna Vertebral
5.
Adv Gerontol ; 32(1-2): 45-54, 2019.
Artigo em Russo | MEDLINE | ID: mdl-31228367

RESUMO

The hypothesis of dependence of the functional characterizations of bone marrow cells (BMC) - proliferation rate, direction proliferation, etc. - not only by the age of animals, but also on features of BMC microenvironment was verified. Two methods of changing the microenvironment were used. There were in vivo (induction of liver fibrosis in young and old animals) and in vitro (transfer of young and old animals BMC obtained in intact animals and animals with fibrosis into the same standard culture system). CuSO4-induced liver fibrosis and CCl4-induced liver fibrosis had a different effect on the ratio of cell types in the bone marrow in young and old animals. Thus, in young animals, regardless of the type of liver fibrosis inducer, the relative number of morphologically identifiable cell types decreased. This was accompanied by an increase in the number of identified cell types against the background of CuSO4-induced liver fibrosis and did not change against the background of CCl4-induced liver fibrosis in old animals. The proliferative activity of BMC isolated from old animals and transferred to an in vitro culture was superior to that of young animals. This is due to the large number of lymphocytes in the bone marrow of old animals by 167% and the specific composition and characteristics of the BMC microenvironment in old animals.


Assuntos
Envelhecimento , Células da Medula Óssea , Cirrose Hepática , Envelhecimento/fisiologia , Animais , Células da Medula Óssea/fisiologia
6.
Bull Exp Biol Med ; 164(3): 293-297, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29308569

RESUMO

Expression of inducible NO-synthase mRNA and myocardial infiltration with neutrophils were studied in rats with modeled permanent ischemia and ischemia/reperfusion models. Expression of inducible NO synthase mRNA in the ischemic region increased significantly in 3, 3.5, and 4 h in modeled ischemia/reperfusion and in 3.5 and 4 h in permanent ischemia. Myocardial infiltration with neutrophils was significantly higher than in intact controls throughout the experiment without significant intergroup differences. In non-ischemic myocardium, enhanced expression of inducible NO synthase mRNA and moderate neutrophilic-lymphocytic myocardial infiltration were also observed in 3.5, and 4 h after ischemia.


Assuntos
Linfócitos/imunologia , Traumatismo por Reperfusão Miocárdica/genética , Miocárdio/enzimologia , Neutrófilos/imunologia , Óxido Nítrico Sintase Tipo II/genética , RNA Mensageiro/genética , Animais , Animais não Endogâmicos , Movimento Celular , Regulação da Expressão Gênica , Linfócitos/citologia , Masculino , Traumatismo por Reperfusão Miocárdica/enzimologia , Traumatismo por Reperfusão Miocárdica/imunologia , Traumatismo por Reperfusão Miocárdica/patologia , Miocárdio/imunologia , Miocárdio/patologia , Infiltração de Neutrófilos , Neutrófilos/citologia , Óxido Nítrico Sintase Tipo II/metabolismo , RNA Mensageiro/metabolismo , Ratos , Fatores de Tempo
7.
Dokl Biol Sci ; 480(1): 93-96, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-30009348

RESUMO

The data on the content of carbon and nitrogen isotopes in the blood samples of polar bears obtained in the present study confirm that polar bears in the Taimyr region (and the Kara-Barents sea population in general) are partly dependent on the resources of terrestrial origin. However the "terrestrial carbon" evidently reaches bears' tissues indirectly, via marine food webs utilizing organic carbon brought into the polar basin by Siberian rivers.


Assuntos
Isótopos de Carbono/sangue , Cadeia Alimentar , Isótopos de Nitrogênio/sangue , Ursidae/sangue , Animais , Regiões Árticas , Feminino , Masculino , Sibéria
8.
Dokl Biol Sci ; 472(1): 17-20, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28429262

RESUMO

The polar bear movement trajectory in relation to onset date of the sea-ice break-up was studied in the coastal zone of the Taimyr Peninsula, eastern part of the Kara Sea, using as an example a female polar bear tagged by a radio collar with an Argos satellite transmitter. Analysis of the long-term pattern of ice melting and tracking, by means of satellite telemetry, of the female polar bear who followed the ice-edge outgoing in the north-eastern direction (in summer 2012) suggests that direction of the polar bear movement depends precisely on the direction of the sea-ice cover break-up.


Assuntos
Migração Animal/fisiologia , Gelo , Estações do Ano , Ursidae/fisiologia , Animais , Regiões Árticas , Feminino
9.
Pharmacopsychiatry ; 47(7): 263-7, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25295551

RESUMO

INTRODUCTION: Literature assessing effective clozapine augmentation strategies is limited. The aim of this retrospective evaluation was to examine antipsychotics used to augment clozapine and assess whether an augmentation antipsychotic would continue at discharge. METHODS: Demographic, clinical and pharmacy data were collected retrospectively if patients had received clozapine plus an antipsychotic used for augmentation. The dose of the augmentation agent, length of augmentation therapy, and concomitant medications were collected. RESULTS: Of the 49 patients (mean age 45.3±12.1 years), 27 (55%) were male. The mean clozapine dose at discharge was 406.1±121.8 mg. When a first generation antipsychotic (FGA) was selected initially to augment clozapine there was a greater likelihood it would be continued until discharge compared to a second generation antipsychotic (SGA) (78 vs. 50%, OR=3.6, 95% CI 1.03-12.6). FGAs (3.2%) compared to SGAs (35%) were less likely to be discontinued due to a documented lack of benefit when first selected to augment clozapine (OR=16.2, 95% CI 2-131.3). Electroconvulsive therapy plus clozapine was found to be beneficial in several patients (n=14) who failed at least 1 augmentation strategy. DISCUSSION: This real world data suggests that adding an antipsychotic to clozapine is a reasonable approach to those who do not fully respond to clozapine monotherapy. While comparisons of all agents could not be conducted from this small retrospective study, these data suggest FGAs should be investigated in future studies as potential agents to successfully augment clozapine therapy.


Assuntos
Antipsicóticos/uso terapêutico , Clozapina/uso terapêutico , Esquizofrenia/tratamento farmacológico , Adulto , Fatores Etários , Antipsicóticos/administração & dosagem , Clozapina/administração & dosagem , Relação Dose-Resposta a Droga , Eletroconvulsoterapia/métodos , Feminino , Hospitalização , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Esquizofrenia/terapia , Fatores Sexuais , Fatores Socioeconômicos
10.
Acta Naturae ; 16(2): 40-49, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39188264

RESUMO

The effects of the antioxidant dihydroquercetin (DHQ) were studied in a model of pulmonary fibrosis. DHQ penetration into the lesion was facilitated by encapsulation into liposomes. Pulmonary fibrosis was modeled in rats by intratracheal injection of bleomycin. For the first 7 days, the rats in the treatment group received a liposomal emulsion with DHQ, while in the comparator group rats received saline. In the control group, intact rats did not receive any exposure. Thirty days after the initiation, lung function and the pathological lesion volume were assessed by 7T 1H MRI and the lungs were taken for histologic examination. The proportion of fibrous tissue was counted by Masson's trichrome staining. Both experimental groups were characterized by a significant functional pulmonary deficiency, with low mortality and a small lesion area. In the rats treated with DHQ, the distribution of fibrous tissue was significantly altered. Significantly more fibrous tissue was found in the center of the lesion, while significantly less was in the interstitial space of alveoli. Lung density at the same time was lower in the treated lungs. Dihydroquercetin encapsulated in liposomes affects the mechanisms of bleomycin-induced pulmonary fibrosis progression in rats. While accelerated fibrosis of the lesion can restrict inflammatory processes, delayed fibrosis of the interstitium can further improve the functional state of the lungs.

11.
Rev Sci Instrum ; 94(7)2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37428022

RESUMO

We propose a design of 3D printed magnetic stage that allows application of static magnetic fields during magnetic force microscopy measurements. The stage utilizes permanent magnets providing spatial homogeneous magnetic fields. The design, assembly, and installation are described. Numerical calculations of the field distribution are used to optimize the size of magnets and the spatial homogeneity of the field. The stage offers a compact and scalable design, which can be adapted as an accessory onto several commercially available magnetic force microscopy platforms. The stage's utility for in situ magnetic field application during magnetic force microscopy measurements is demonstrated on a sample of thin ferromagnetic strips.

12.
Izv Akad Nauk Ser Biol ; (3): 358-63, 2011.
Artigo em Russo | MEDLINE | ID: mdl-21790001

RESUMO

A noninvasive evaluation method of hypothalamo-pituitary-adrenals axis (HPA) activity in the Siberian tiger was verified. Comparison of the activity level of HPA in Siberian tigers in the wild and in captivity, and their alterations over the year was carried out. Significant seasonal deviations between activity levels of HPA in tigers in captivity were not found. In the wild, this level was significantly higher, reaching the maximum from November to January, which can be related with an unfavorable influence on tigers in low temperatures and deep snow cover.


Assuntos
Animais Selvagens , Animais de Zoológico , Hidrocortisona/sangue , Sistema Hipófise-Suprarrenal/metabolismo , Tigres/metabolismo , Animais , Monitoramento Ambiental , Fezes/química , Feminino , Masculino , Estações do Ano , Sibéria
13.
Vopr Onkol ; 57(1): 75-80, 2011.
Artigo em Russo | MEDLINE | ID: mdl-21598713

RESUMO

Data are presented on the results of photodynamic treatment (PDT) of mice DBA2 with transplantable lympho-leukemia P-388. Different regimens of photosensitizer Dimegin and emission were used. Both intravenous PDT and in combination with local PDT should be recommended.


Assuntos
Deuteroporfirinas/uso terapêutico , Leucemia Experimental/tratamento farmacológico , Linfoma/tratamento farmacológico , Fármacos Fotossensibilizantes/uso terapêutico , Animais , Camundongos , Camundongos Endogâmicos DBA , Neoplasias Experimentais/tratamento farmacológico , Fotoquimioterapia/instrumentação , Fotoquimioterapia/métodos , Transplante Heterólogo , Resultado do Tratamento
14.
Bull Exp Biol Med ; 149(4): 485-9, 2010 Oct.
Artigo em Inglês, Russo | MEDLINE | ID: mdl-21234449

RESUMO

Oxidative (respiratory) burst is an important manifestation of inflammation. Precise quantitative assessment of this reaction by flow cytometry made it possible to record and evaluate the severity of the inflammatory processes in a wide spectrum of diseases including diphtheria, hepatitis, pneumonia, bronchial asthma, arthritis, vasculitis, postoperative complications, tuberculosis, psoriasis, rheumatoid arthritis, systemic lupus erythematosus, and myocardial infarction. This approach can be employed as a highly sensitive method of detection of inflammatory reactions and monitoring of their course in various pathological processes.


Assuntos
Inflamação/diagnóstico , Neutrófilos/metabolismo , Explosão Respiratória , Artrite/complicações , Asma/complicações , Criança , Citometria de Fluxo , Humanos , Lúpus Eritematoso Sistêmico/complicações , Infarto do Miocárdio/complicações , Fenantridinas , Pneumonia/complicações , Tuberculose/complicações , Vasculite/complicações
15.
Prikl Biokhim Mikrobiol ; 46(3): 315-23, 2010.
Artigo em Russo | MEDLINE | ID: mdl-20586284

RESUMO

The ability of Azotobacter chroococcum strain 7B, producer of polyhydroxybutyrate (PHB), to synthesize its copolymer poly-3-hydroxybutyrate-3-hydroxyvalerate (PHB-HV) was studied. It was demonstrated, for the first time, that A. chroococcum strain 7B was able to synthesize PHB-HV with various molar rates of HV in the polymer chain when cultivated on medium with sucrose and carboxylic acids as precursors of HV elements in the PHB chain, namely, valeric (13.1-21.6 mol %), propanoic (3.1 mol %), and hexanoic (2.1 mol %) acids. Qualitative and functional differences between PHB and PHB-HV were demonstrated by example of the release kinetic of methyl red from films made of synthesized polymers. Maximal HV incorporation into the polymer chain (28.8 mol %) was recorded when the nutrient medium was supplemented with 0.1% peptone on the background of 20 mM valerate. These results suggest that that the studied strain can be regarded as a potential producer of not only PHB but also PHB-HV.


Assuntos
Azotobacter/genética , Azotobacter/metabolismo , Hidroxibutiratos/metabolismo , Poliésteres/metabolismo , Ácidos Carboxílicos/farmacologia , Hidroxibutiratos/química , Poliésteres/química , Sacarose/farmacologia
16.
J Mech Behav Biomed Mater ; 108: 103839, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32469711

RESUMO

An exceptional combination of low Young's modulus (E ~68 GPa) and high flow strength (σf ~1 GPa) was achieved for a consolidated ß-Ti-based metastable Ti-35Nb-7Zr-5Ta (TNZT) alloy subjected to room temperature high-pressure torsion (HPT). The mechanical properties of the alloy were studied by quasistatic nanoindentation tests at different strain rates, where a reduction in Young's modulus E ~73 GPa (NHPT10) and E ~68 GPa (NHPT40) is observed together with an increase in plastic deformability (or HPT rotations). The microstructure evolution with increasing shear strain has been investigated. The stabilized bcc ß-Ti phase with homogeneous nanostructure distribution was observed leading to a low Young's modulus. Severe straining causes a uniform hardness distribution without any noticeable change in the strength of the material. This study may be useful for developing excellent removable implant materials.


Assuntos
Ligas , Titânio , Módulo de Elasticidade , Dureza , Próteses e Implantes
17.
Opt Express ; 17(24): 21935-43, 2009 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-19997438

RESUMO

It has become a significant challenge to accurately characterise the properties of recently developed very high finesse optical resonators (F > 10(6)). A similar challenge is encountered when trying to measure the properties of cavities in which either the probing laser or the cavity length is intrinsically unstable. We demonstrate in this article the means by which the finesse, mode-matching, free spectral range, mirror transmissions and dispersion may be measured easily and accurately even when the laser or cavity has a relatively poor intrinsic frequency stability.


Assuntos
Lasers , Óptica e Fotônica , Algoritmos , Óxido de Alumínio/química , Calibragem , Desenho Assistido por Computador , Desenho de Equipamento , Dispositivos Ópticos , Reprodutibilidade dos Testes , Titânio/química
18.
Opt Express ; 17(7): 5897-904, 2009 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-19333360

RESUMO

There is great interest in developing high performance optical frequency metrology based around mode-locked fibre lasers because of their low cost, small size and long-term turnkey operation when compared to the solid-state alternative. We present a method for stabilising the offset frequency of a fibre-based laser comb using a 2 f - 3 f technique based around a unique fibre that exhibits strong resonant dispersive wave emission. This fibre requires lower power than conventional highly non-linear fibre to generate a suitable signal for offset frequency stabilisation and this in turn avoids the complexity of additional nonlinear steps. We generate an offset frequency signal from the mixing of a wavelength-shifted second harmonic comb with a third harmonic of the comb. Additionally, we have stabilised the repetition rate of the laser to a level better than 10(-14)/ radicaltau , limited by the measurement system noise floor.We present the means for complete and precise measurement of the transfer function of the laser frequency controls.


Assuntos
Tecnologia de Fibra Óptica/instrumentação , Filtração/instrumentação , Lasers , Desenho Assistido por Computador , Desenho de Equipamento , Análise de Falha de Equipamento , Miniaturização , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
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