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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.
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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.
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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.
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Traumatismos de la Médula Espinal/diagnóstico , Neoplasias de la Médula Espinal , Potenciales Evocados Motores , Humanos , Médula Espinal , Columna VertebralRESUMEN
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.
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Aleaciones , Titanio , Módulo de Elasticidad , Dureza , Prótesis e ImplantesRESUMEN
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.
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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.
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Envejecimiento , Células de la Médula Ósea , Cirrosis Hepática , Envejecimiento/fisiología , Animales , Células de la Médula Ósea/fisiologíaRESUMEN
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.
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Isótopos de Carbono/sangre , Cadena Alimentaria , Isótopos de Nitrógeno/sangre , Ursidae/sangre , Animales , Regiones Árticas , Femenino , Masculino , SiberiaRESUMEN
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.
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Linfocitos/inmunología , Daño por Reperfusión Miocárdica/genética , Miocardio/enzimología , Neutrófilos/inmunología , Óxido Nítrico Sintasa de Tipo II/genética , ARN Mensajero/genética , Animales , Animales no Consanguíneos , Movimiento Celular , Regulación de la Expresión Génica , Linfocitos/citología , Masculino , Daño por Reperfusión Miocárdica/enzimología , Daño por Reperfusión Miocárdica/inmunología , Daño por Reperfusión Miocárdica/patología , Miocardio/inmunología , Miocardio/patología , Infiltración Neutrófila , Neutrófilos/citología , Óxido Nítrico Sintasa de Tipo II/metabolismo , ARN Mensajero/metabolismo , Ratas , Factores de TiempoRESUMEN
Surface-enhanced Raman spectroscopy is a powerful analytical method, and is especially useful for the detection of nitrogen- and sulfur-containing organic substances in trace amounts. SERS substrates with high enhancement factors can be produced via the aggregation of gold nanoparticles, leading to the formation of 'hot spots' - regions of highest electric field intensity and Raman scattering enhancement. Thus, the availability of gold surfaces in 'hot spots' for the adsorption of analyte molecules strongly influences the enhancement factor of a substrate. We studied the kinetics of oxidation of dyes with hydrogen peroxide in the presence of citrate-capped gold nanoparticles and discovered the amplification of surface-enhanced Raman scattering, probably due to the oxidation of citrate ligands and the additional adsorption of dye molecules onto vacant spots on the gold surface. Maximum amplification was observed with 3% (v/v) hydrogen peroxide in the reaction medium. Under optimized conditions, model analytes can be detected at concentrations as low as 1 × 10-9 M, which is ten times lower than the detection limit without hydrogen peroxide addition.
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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.
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Migración Animal/fisiología , Hielo , Estaciones del Año , Ursidae/fisiología , Animales , Regiones Árticas , FemeninoRESUMEN
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.
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Antipsicóticos/uso terapéutico , Clozapina/uso terapéutico , Esquizofrenia/tratamiento farmacológico , Adulto , Factores de Edad , Antipsicóticos/administración & dosificación , Clozapina/administración & dosificación , Relación Dosis-Respuesta a Droga , Terapia Electroconvulsiva/métodos , Femenino , Hospitalización , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Esquizofrenia/terapia , Factores Sexuales , Factores SocioeconómicosAsunto(s)
Migración Animal , Locomoción , Ursidae/fisiología , Animales , Regiones Árticas , Ecosistema , FemeninoRESUMEN
Cylindrical re-entrant cavities are unique three-dimensional structures that resonate with their electric and magnetic fields in separate parts of the cavity. To further understand these devices, we undertake rigorous analysis of the properties of the resonance using "in-house" developed Finite Element Method (FEM) software capable of dealing with small gap structures of extreme aspect ratio. Comparisons between the FEM method and experiments are consistent and we illustrate where predictions using established lumped element models work well and where they are limited. With the aid of the modeling we design a highly tunable cavity that can be tuned from 2 GHz to 22 GHz just by inserting a post into a fixed dimensioned cylindrical cavity. We show this is possible, as the mode structure transforms from a re-entrant mode during the tuning process to a standard cylindrical transverse magnetic mode.
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A biodegradable polymer of bacterial origin, poly(3-hydroxybutyrate) (PHB), is intensively studied as biomaterial for tissue engineering. However, factors determining its biocompatibility still require better understanding. To analyze the PHB films biocompatibility, the polymer material was modified by hydrophilic polymer, poly(ethylene glycol) 300 (PEG). The blends PHB/PEG with different PEG content (10, 20, 30 and 50%) were produced by subsequent incubation in water resulted in removal of 95% PEG. The surface roughness and hydrophilicity were studied by atomic force microscopy (AFM) and contact angle "water-polymer" measurement, respectively. The film biocompatibility on cell culture of COS-1 fibroblasts was studied in vitro. It was shown that both roughness and hydrophobicity are directly proportional to initial PEG content in the PHB/PEG blends. The growth rate of COS-1 fibroblasts on polymer films is determined by combination of two basic physicochemical properties of the polymer surface: the roughness and hydrophilicity. The optimal roughness requred for COS-1 cells growth is the average roughness more than 25 nm, whereas the limit values of the contact angle "water-polymer" that was responsible for relatively high cell viability were not found. These data indicate that the film surface roughness had the greatest effect on the cell growth, whereas the increase in the polymer surface hydrophilicity caused the additional positive effect on viability of attached cells. Thus, the modification of PHB polymer material by PEG resulted in the improved viability of cells cultivated on the polymer films in vitro. The obtained data can be used for development of such medical devices as surgeon patches and periodontal membranes.
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Hidroxibutiratos/química , Membranas Artificiales , Poliésteres/química , Polietilenglicoles/química , Implantes Absorbibles , Animales , Células COS , Adhesión Celular , Supervivencia Celular , Chlorocebus aethiops , Ensayo de Materiales , Propiedades de SuperficieRESUMEN
For heterodyne phase locking, frequency division of the beat note between two oscillators can improve the reliability of the phase lock and the quality of the phase synchronization. Frequency division can also reduce the size, weight, power, and cost of the instrument by excluding the microwave synthesizer from the control loop when the heterodyne offset frequency is large (5 to 10 GHz). We have experimentally tested the use of a frequency divider in an optical phase-lock loop and compared the achieved level of residual phase fluctuations between two diode lasers with that achieved without the use of a frequency divider. The two methods achieve comparable phase stability provided that sufficient loop gain is maintained after frequency division to preserve the required bandwidth. We have also numerically analyzed the noise properties and internal dynamics of phase-locked loops subjected to a high level of phase fluctuations, and our modeling confirms the expected benefits of having an in-loop frequency divider.
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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.
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Animales Salvajes , Animales de Zoológico , Hidrocortisona/sangre , Sistema Hipófiso-Suprarrenal/metabolismo , Tigres/metabolismo , Animales , Monitoreo del Ambiente , Heces/química , Femenino , Masculino , Estaciones del Año , SiberiaRESUMEN
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.
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Deuteroporfirinas/uso terapéutico , Leucemia Experimental/tratamiento farmacológico , Linfoma/tratamiento farmacológico , Fármacos Fotosensibilizantes/uso terapéutico , Animales , Ratones , Ratones Endogámicos DBA , Neoplasias Experimentales/tratamiento farmacológico , Fotoquimioterapia/instrumentación , Fotoquimioterapia/métodos , Trasplante Heterólogo , Resultado del TratamientoRESUMEN
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.
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Azotobacter/genética , Azotobacter/metabolismo , Hidroxibutiratos/metabolismo , Poliésteres/metabolismo , Ácidos Carboxílicos/farmacología , Hidroxibutiratos/química , Poliésteres/química , Sacarosa/farmacologíaRESUMEN
We developed a novel technique for accurate phase synchronization of microwave oscillators based on sapphire dielectric resonators cooled to liquid nitrogen temperature. The achieved quality of phase synchronization (a few milliradians) enables the accurate measurements of extremely weak phase fluctuations expected from the next generation of ultralow phase noise microwave oscillators.