Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 35
Filtrar
1.
Mol Phylogenet Evol ; 195: 108057, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38471598

RESUMEN

Previous efforts to reconstruct evolutionary history of Palearctic ground squirrels within the genus Spermophilus have primarily relied on a single mitochondrial marker for phylogenetic data. In this study, we present the first phylogeny with comprehensive taxon sampling of Spermophilus via a conventional multilocus approach utilizing five mitochondrial and five nuclear markers. Through application of the multispecies coalescent model, we constructed a species tree revealing four distinct clades that diverged during the Late Miocene. These clades are 1) S. alaschanicus and S. dauricus from East Asia; 2) S. musicus and S. pygmaeus from East Europe and northwestern Central Asia; 3) the subgenus Colobotis found across Central Asia and its adjacent regions and encompassing S. brevicauda, S. erythrogenys, S. fulvus, S. major, S. pallidicauda, S. ralli, S. relictus, S. selevini, and S. vorontsovi sp. nov.; and 4) a Central/Eastern Europe and Asia Minor clade comprising S. citellus, S. taurensis, S. xanthoprymnus, S. suslicus, and S. odessanus. The latter clade lacked strong support owing to uncertainty of taxonomic placement of S. odessanus and S. suslicus. Resolving relationships within the subgenus Colobotis, which radiated rapidly, remains challenging likely because of incomplete lineage sorting and introgressive hybridization. Most of modern Spermophilus species diversified during the Early-Middle Pleistocene (2.2-1.0 million years ago). We propose a revised taxonomic classification for the genus Spermophilus by recognizing 18 species including a newly identified one (S. vorontsovi sp. nov.), which is found only in a limited area in the southeast of West Siberia. Employing genome-wide single-nucleotide polymorphism genotyping, we substantiated the role of the Ob River as a major barrier ensuring robust isolation of this taxon from S. erythrogenys. Despite its inherent limitations, the traditional multilocus approach remains a valuable tool for resolving relationships and can provide important insights into otherwise poorly understood groups. It is imperative to recognize that additional efforts are needed to definitively determine phylogenetic relationships between certain species of Palearctic ground squirrels.


Asunto(s)
Introgresión Genética , Sciuridae , Animales , Siberia , Filogenia , Sciuridae/genética , Asia
2.
Molecules ; 27(22)2022 Nov 16.
Artículo en Inglés | MEDLINE | ID: mdl-36432038

RESUMEN

Here, we introduce an advanced mathematical model for the sublimation of thin films of explosives. The model relies on the Hertz-Knudsen-Langmuir (HKL) equation that describes the vaporization rate of an explosive and controls the mass exchange between the surface and the ambient air. The latest experimental data on sublimation and diffusion of 2,4,6-trinitrotoluene (TNT) monocrystals were factored in, as well as the data on the sublimation rate of hexogen (RDX), octogen (HMX), and picramide (TNA) traces. To advance the mathematical model we suggested previously, we took into account the structure of a substrate on which a thin explosive layer was deposited. The measurement problem of the sublimation rate and limits of an explosive arises from developing and advancing remote detection methods for explosives traces. Using mathematical modelling, we can identify a detectable quantity of a specific explosive under given conditions. We calculated the mass of the explosive in the air upon sublimation of thin explosive films from the surfaces over a wide range of the parameters in question and made conclusions regarding the application limits of the devised standoff trace explosive detection techniques.

3.
Tumour Biol ; 37(9): 12011-12021, 2016 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-27164936

RESUMEN

Thyroid cancer (TC) is the most common endocrine malignancy and its incidence has increased over the last few decades. As has been revealed by a number of studies, TC tissue's micro-RNA (miRNA) profile may reflect histological features and the clinical behavior of tumor. However, alteration of the miRNA profile of plasma exosomes associated with TC development has to date not been explored. We isolated exosomes from plasma and assayed their characteristics using laser diffraction particle size analysis, atomic force microscopy, and western blotting. Next, we profiled cancer-associated miRNAs in plasma exosomes obtained from papillary TC patients, before and after surgical removal of the tumor. The diagnostic value of selected miRNAs was evaluated in a large cohort of patients displaying different statuses of thyroid nodule disease. MiRNA assessment was performed by RT-qPCR. In total, 60 patients with different types of thyroid nodal pathology were included in the study. Our results revealed that the development of papillary TC is associated with specific changes in exosomal miRNA profiles; this phenomenon can be used for differential diagnostics. MiRNA-31 was found to be over-represented in the plasma exosomes of patients with papillary TC vs. benign tumors, while miRNA-21 helped to distinguish between benign tumors and follicular TC. MiRNA-21 and MiRNA-181a-5p were found to be expressed reciprocally in the exosomes of patients with papillary and follicular TC, and their comparative assessment may help to distinguish between these types of TC with 100 % sensitivity and 77 % specificity.


Asunto(s)
Adenocarcinoma Folicular/genética , Carcinoma/genética , Exosomas/química , MicroARNs/sangre , Neoplasias de la Tiroides/genética , Adulto , Carcinoma Papilar , Diagnóstico Diferencial , Femenino , Humanos , Masculino , Persona de Mediana Edad , Cáncer Papilar Tiroideo
4.
Zootaxa ; 3784: 493-7, 2014 Mar 31.
Artículo en Inglés | MEDLINE | ID: mdl-24872067

RESUMEN

The Holarctic genus Euchalcia Hübner, [1821] belongs to the tribe Plusiini of the subfamily Plusiinae. The genus is one of the largest in the Plusiinae, comprising about 54 described species. The systematics of Eurasian and North African members of the genus was recently revised (Ronkay et al. 2008). In June 2013, in the course of faunistic studies on Noctuidae of the Tarbagatai Mts. (East Kazakhstan), a long series of an undescribed species of the genus was collected. Two additional specimens from the Dzhungarsky Alatau Mts. (South-East Kazakhstan) were found in the collection of the Siberian Zoological Museum (Novosibirsk). The species is described herein as new. It belongs to the E. inconspicua group within the E. inconspicua species-complex (Ronkay et al. 2008). The E. inconspicua group comprises two described species only: E. inconspicua (Graeser, 1892) and E. anthea L. Ronkay, G. Ronkay & Behounek, 2008. The new species is the northernmost member of the group. Institutional acronyms are as follows: AVB-coll. A.V. Volynkin, Barnaul, Russia; MCK-coll. M. Cernila, Kamnik, Slovenia; NHMW-Naturhistorisches Museum, Vienna, Austria; STP-coll. S.V. Titov, Pavlodar, Kazakhstan; SZMN-Siberian Zoological Museum of the Institute of Animal Systematic and Ecology of the Siberian Branch of the Russian Academy of Sciences (Novosibirsk, Russia), ZISP-Zoological Institute of Russian Academy of Sciences, St. Petersburg, Russia.


Asunto(s)
Mariposas Nocturnas/clasificación , Distribución Animal , Estructuras Animales/anatomía & histología , Animales , Ecosistema , Femenino , Kazajstán , Masculino , Mariposas Nocturnas/anatomía & histología , Federación de Rusia , Eslovenia
5.
Zootaxa ; 3753: 494-500, 2014 Jan 09.
Artículo en Inglés | MEDLINE | ID: mdl-24869511

RESUMEN

Orthosia Ochsenheimer, 1816 is a Holarctic-Oriental noctuid genus comprising more than 60 described species, with most distributed in the eastern and southeastern Palaearctic and Oriental regions. Many species have recently been described from Asia (Hreblay 1991, 1993, 1994; Yoshimoto 1993; Hreblay & Plante 1994; Hreblay & Ronkay 1998, 1999; Ronkay et al. 2010, Saldaitis et al. 2011, etc.). The O. incerta species-group includes 10 described species (see Ronkay et al. 2001), and during the course of faunistic studies on the Noctuidae of North-East Kazakhstan, a new member of this species-group was found; it is described herein as new. 


Asunto(s)
Mariposas Nocturnas/anatomía & histología , Mariposas Nocturnas/clasificación , Animales , Ecosistema , Femenino , Kazajstán , Masculino , Mariposas Nocturnas/fisiología
6.
Animals (Basel) ; 14(18)2024 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-39335309

RESUMEN

Colonizing populations at the leading edge of range expansion are expected to have a reduced genetic diversity and strong genetic structure caused by genetic drift and allele surfing. Until now, few studies have found the genetic signatures of allele surfing in expanding wild populations. Using mtDNA markers, we studied the genetic structure of the population of midday gerbils (Meriones meridianus) expanding their range to the west in Kalmykia (southern Russia) following the new cycle of desertification, re-colonizing areas abandoned in the mid-2010s. In the colonizing population, we found a reduced genetic diversity, the redistribution of haplotype frequencies-in particular, in favor of variants rare in the core population-and strong genetic structure combined with strong differentiation from the core population-patterns suggestive of allele surfing on the wave of expansion. In terms of genetic diversity and spatial structuration, the western edge population sampled in 2008 before its collapse in 2017 occupies the intermediate position between the current colonizing and core population. This suggests that reduced genetic diversity and increased genetic differentiation are general features of marginal populations, enhanced by the founder and allele-surfing effects at the leading edges of expanding ranges.

7.
Integr Zool ; 18(3): 469-492, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36054534

RESUMEN

The spatial genetic structure is a topical issue in the studies of various aspects of ecology and evolution. Using the multilocus autocorrelation method with hypervariable microsatellite genetic markers, we investigated a fine-scale pattern of genetic structure in 5 local populations of the common shrew Sorex araneus separated by distances of 300-1000 m (the Moscow chromosomal race). Spatial genetic autocorrelation analysis based on 5 microsatellite loci (expected heterozygosity >0.79) with 90 alleles revealed a consistent pattern of significant positive genetic structure. By testing the autocorrelation at multiple scales from 25 to 500 m, we found that positive spatial genetic structure is detectable in distance classes of <500 m. The weaker spatial genetic structure positively correlated with a higher ratio of nonresident individuals to residents' activity (number of captures). In contrast to nonresident animals, the residents demonstrated prominent genetic structure. Genetic difference (FST ) between the populations was significant (0.016-0.051) and comparable with that between populations of different races analyzed previously (0.016-0.038). FST was not associated with geographic distance. These demographic patterns allowed us to propose a scheme of genetic-structure dynamics involving periodic appearance of more related local groups and renewal of allelic profiles from а common pool where the alleles are mixed. The scheme predicts fluctuating genetic structure and random similar differences among local populations.


Asunto(s)
Eulipotyphla , Musarañas , Animales , Musarañas/genética , Eulipotyphla/genética , Repeticiones de Microsatélite/genética , Variación Genética
8.
Biology (Basel) ; 12(6)2023 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-37372163

RESUMEN

Among the numerous described cases of hybridization in mammals, the most intriguing are (a) cases of introgressive hybridization deeply affecting the evolutionary history of species, and (b) models involving not a pair of species but a multi-species complex. Therefore, the hybridization history of the russet ground squirrel Spermophilus major, whose range has repeatedly changed due to climatic fluctuations and now borders the ranges of four related species, is of great interest. The main aims of this study were to determine the direction and intensity of gene introgression, the spatial depth of the infiltration of extraneous genes into the S. major range, and to refine the hypothesis of the hybridogenic replacement of mitochondrial genomes in the studied group. Using phylogenetic analysis of the variability of mitochondrial (CR, cytb) and nuclear (SmcY, BGN, PRKCI, c-myc, i6p53) markers, we determined the contribution of neighboring species to the S. major genome. We showed that 36% of S. major individuals had extraneous alleles. All peripheral species that were in contact with S. major contributed towards its genetic variability. We also proposed a hypothesis for the sequence and localization of serial hybridization events. Our assessment of the S. major genome implications of introgression highlights the importance of implementing conservation measures to protect this species.

9.
Cureus ; 15(3): e35906, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37033545

RESUMEN

INTRODUCTION: The study of brain tumors has shown that microRNAs can act as both oncogenes and tumor suppressors and, consequently, can be used as biomarkers for the diagnosis and prognosis of such tumors. Thus, big interest arises in the role of microRNA and its part in oncogenesis in the human brain to find key molecules that can act as tumor markers for diagnostic and prognostic purposes, as well as potential therapeutic agents. STUDY AIM: The sim of this study was to assess histological, molecular, and genetic metrics in patients with supratentorial gliomas, and indicate diagnostic and prognostic abilities of microRNA usage as biomarkers of the grade of malignancy of the tumor. MATERIALS AND METHODS: Clinical and genetic studies were performed in 107 operated patients with supratentorial gliomas of different malignancies. The expression levels of 10 microRNAs (-16, -21¸ -31, -124, - 125b, -181b, -191, -221, -223, and -451) were analyzed using real-time polymerase chain reaction (PCR). The results were analyzed statistically using Statistica 12.0 (Statistica, Hamburg, Germany) and GraphPad Prism 9 software (GraphPad Software Inc., Boston, Massachusetts, United States). RESULTS: Based on a comprehensive statistical analysis involving the database of the clinical results of treatment of all 107 patients (combined treatment methods, quality of life, and survival) and microRNA expression levels, specific profiles of microRNA expression typical of different histotypes of gliomas of different malignancy were identified, the prognostic significance of the studied microRNAs as potential predictors of survival in patients with brain gliomas was determined, and microRNAs with the highest prognostic value were identified among them.

10.
Biology (Basel) ; 12(5)2023 May 19.
Artículo en Inglés | MEDLINE | ID: mdl-37237562

RESUMEN

This article presents data on the mesonephros histology and ultrastructure in the Atlantic salmon from the Baltic Sea and Barents Sea populations, with an emphasis on comparisons between the following ontogenetic stages: parr, smolting, adult life at sea, the adults' return to their natal river to spawn, and spawning. The ultrastructural changes in the renal corpuscle and cells of the proximal tubules of the nephron occurred as early as the smolting stage. Such changes reflect fundamental alterations during the pre-adaptation to life in saltwater. In the Barents Sea population, the adult salmon sampled in the sea had the smallest diameters of the renal corpuscle and proximal and distal tubules, the most narrow urinary space, and the thickest basement membrane. In the group of salmon that entered the mouth of the river and spent less than 24 h in freshwater, the structural rearrangements occurred only in the distal tubules. Better development of the smooth endoplasmic reticulum and a greater abundance of mitochondria in the tubule cells were observed in the adult salmon from the Barents Sea compared to those from the Baltic Sea. Cell-immunity activation was initiated during the parr-smolt transformation. Another pronounced innate-immunity response was registered in the adults returning to the river to spawn.

11.
Zootaxa ; 5374(3): 409-423, 2023 Nov 17.
Artículo en Inglés | MEDLINE | ID: mdl-38220853

RESUMEN

Two new species of the genus Isochlora Staudinger, 1882 are described: I. hreblayi Volynkin, Tth, Titov & Saldaitis, sp. n. (western Mongolia) and I. kozlovi Volynkin, Titov, Matov & Saldaitis, sp. n. (Qinghai Province, China). The type species of the genus-group names Chamyla Staudinger, 1900 and Grumia Alphraky, 1892 (I. arctomys Alphraky, 1897 and I. flora (Alphraky, 1892), respectively) are examined, and their synonymy with Isochlora is revised. The synonymy of Chamyla idia Staudinger, 1900 with Isochlora arctomys Alphraky, 1897 is revised as junior synonymies. Lectotypes are designated for Isochlora arctomys Alphraky, 1897, Chamyla idia Staudinger, 1900 and Grumia flora Alphraky, 1892. Isochlora intricans (Alphraky, 1882) is reported from Kazakhstan for the first time. Adults as well as male and female genitalia are illustrated.


Asunto(s)
Lepidópteros , Mariposas Nocturnas , Masculino , Femenino , Animales , Mongolia , Distribución Animal , China
12.
Materials (Basel) ; 15(5)2022 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-35269023

RESUMEN

The structure of the acoustic field defines the key parameters of acousto-optical (AO) devices. To confirm their compliance with the expected values in the presence of multiple real factors, AO crystalline cells require accurate experimental investigation of the acoustic field after being totally assembled. For this purpose, we propose to detect and quantify all the acoustic waves propagating in AO cells using an impulse acoustic microscopy technique. To validate this approach, we have analyzed both theoretically and experimentally the modes, amplitudes, propagation trajectories, and other features of the ultrasonic waves generated inside an AO modulator made of fused quartz. Good correspondence between theoretical and experimental data confirms the effectiveness of the proposed technique.

13.
J Chem Phys ; 134(4): 044530, 2011 Jan 28.
Artículo en Inglés | MEDLINE | ID: mdl-21280771

RESUMEN

Inertial effects in the rotational brownian motion in space of a rigid dipolar rotator (needle) in a uniaxial potential biased by an external field giving rise to asymmetry are treated via the infinite hierarchy of differential-recurrence relations for the statistical moments (orientational correlation functions) obtained by averaging the Euler-Langevin equation over its realizations in phase space. The solutions of this infinite hierarchy for the dipole correlation function and its characteristic times are obtained using matrix continued fractions showing that the model simultaneously predicts both slow overbarrier (or interwell) relaxation at low frequencies accompanied by intermediate frequency Debye relaxation due to fast near-degenerate motion in the wells of the potential (intrawell relaxation) as well as the high frequency resonance (Poley) absorption due to librations of the dipole moments. It is further shown that the escape rate of a brownian particle from a potential well as extended to the Kramers turnover problem via the depopulation factor yields a close approximation to the longest (overbarrier) relaxation time of the system. For zero and small values of the bias field parameter h, both the dipole moment correlation time and the longest relaxation time have Arrhenius behavior (exponential increase with increasing barrier height). While at values of h in excess of a critical value however far less than that required to achieve nucleation, the Arrhenius behavior of the correlation time disappears.

14.
PLoS One ; 16(1): e0244983, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33400714

RESUMEN

Here we look into the spread of aerosols indoors that may potentially carry viruses. Many viruses, including the novel SARS-CoV-2, are known to spread via airborne and air-dust pathways. From the literature data and our research on the propagation of fine aerosols, we simulate herein the carryover of viral aerosols in indoor air. We demonstrate that a lot of fine droplets released from an infected person's coughing, sneezing, or talking propagate very fast and for large distances indoors, as well as bend around obstacles, lift up and down over staircases, and so on. This study suggests equations to evaluate the concentration of those droplets, depending on time and distance from the source of infection. Estimates are given for the safe distance to the source of infection, and available methods for neutralizing viral aerosols indoors are considered.


Asunto(s)
COVID-19/transmisión , Transmisión de Enfermedad Infecciosa/prevención & control , Aerosoles/análisis , Microbiología del Aire , Contaminación del Aire Interior/análisis , COVID-19/metabolismo , COVID-19/virología , Tos , Transmisión de Enfermedad Infecciosa/estadística & datos numéricos , Polvo , Humanos , Modelos Teóricos , SARS-CoV-2/aislamiento & purificación , Estornudo/fisiología , Virosis/prevención & control
15.
Cells ; 9(8)2020 08 18.
Artículo en Inglés | MEDLINE | ID: mdl-32824820

RESUMEN

BACKGROUND: The current approaches to distinguish follicular adenomas (FA) and follicular thyroid cancer (FTC) at the pre-operative stage have low predictive value. Liquid biopsy-based analysis of circulating extracellular vesicles (EVs) presents a promising diagnostic method. However, the extreme heterogeneity of plasma EV population hampers the development of new diagnostic tests. We hypothesize that the isolation of EVs with thyroid-specific surface molecules followed by miRNA analysis, may have improved diagnostic potency. METHODS: The total population of EVs was isolated from the plasma of patients with FA (n = 30) and FTC (n = 30). Thyroid peroxidase (TPO)-positive EVs were isolated from the total populations using immune-beads. The miRNA from the TPO(+)EVs obtained from the plasma of FA and FTC patients was assayed by RT-PCR. The diagnostic potency of the selected miRNAs was estimated by the receiver operating characteristic (ROC) analysis. RESULTS: TPO(+)EVs can be efficiently isolated by immunobeads. The analysis of Let-7 family members in TPO(+)EVs allows one to distinguish FA and FTC with high accuracy (area under curve defined by ROC = 0.77-0.84). CONCLUSION: The isolation of TPO(+)EVs, followed by RT-qPCR analysis of Let-7 family members, may present a helpful approach to manage follicular nodules in the thyroid gland.


Asunto(s)
Adenocarcinoma Folicular/sangre , Adenocarcinoma Folicular/diagnóstico , Adenoma/sangre , Adenoma/diagnóstico , Autoantígenos/metabolismo , Vesículas Extracelulares/metabolismo , Yoduro Peroxidasa/metabolismo , Proteínas de Unión a Hierro/metabolismo , MicroARNs/genética , Nódulo Tiroideo/sangre , Nódulo Tiroideo/diagnóstico , Biomarcadores de Tumor/sangre , Biomarcadores de Tumor/genética , Estudios de Casos y Controles , Diagnóstico Diferencial , Femenino , Humanos , Masculino , Persona de Mediana Edad , Reacción en Cadena en Tiempo Real de la Polimerasa
16.
Zootaxa ; 4563(2): zootaxa.4563.2.6, 2019 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-31716544

RESUMEN

A new species of the genus Victrix Staudinger, 1879, V. akbet Volynkin, Titov Cernila, sp. nov. is described from Kazakhstan. The new species belongs to the subgenus Poliobrya Hampson, 1908. A diagnostic comparison is made with V. frigidalis Varga Ronkay, 1991, V. fabiani Varga Ronkay, 1989 and V. umovii (Eversmann, 1846). The adults and male and female genitalia of the new and related species are illustrated.


Asunto(s)
Lepidópteros , Mariposas Nocturnas , Distribución Animal , Estructuras Animales , Animales , Tamaño Corporal , Femenino , Kazajstán , Masculino , Tamaño de los Órganos
17.
PLoS One ; 14(1): e0210754, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30699153

RESUMEN

Advanced air quality control requires real-time monitoring of particulate matter size and concentration, which can only be done using optical instruments. However, such techniques need regular calibration with reference samples. In this study, we suggest that puffball fungus (Lycoperdon pyriforme) spores can be utilized as a reference standard having a monodisperse size distribution. We compare the Lycoperdon pyriforme spores with the other commonly used reference samples, such as Al2O3 powder and polystyrene latex (PSL) microspheres. Here we demonstrate that the puffball spores do not coagulate and, thus, maintain the same particle size in the aerosol state for at least 15 minutes, which is enough for instrument calibration. Moreover, the puffball mushrooms can be stored for several years and no agglomeration of the spores occurs. They are also much cheaper than other calibration samples and no additional devices are needed for aerosol generation since the fungal fruiting body acts as an atomizer itself. The aforementioned features make the fungal spores a highly promising substance for calibration and validation of particle size analyzers, which outperforms the existing, artificially produced particles for aerosol sampling. Furthermore, the L. pyriforme spores are convenient for basic research and development of new optical measurement techniques, taking into account their uniform particle size and absent coagulation in the aerosol.


Asunto(s)
Agaricales/ultraestructura , Dispositivos Ópticos/normas , Esporas Fúngicas/ultraestructura , Aerosoles , Contaminación del Aire/análisis , Calibración , Humanos , Microscopía Electrónica de Rastreo , Dispositivos Ópticos/estadística & datos numéricos , Tamaño de la Partícula , Material Particulado/análisis , Estándares de Referencia
18.
Int J Pharm ; 547(1-2): 10-23, 2018 Aug 25.
Artículo en Inglés | MEDLINE | ID: mdl-29751140

RESUMEN

Resistance to antiepileptic drugs (AEDs) is a major clinical problem. The overexpression of P-glycoprotein (Pgp), one of the main transporters limiting the entry of xenobiotics into the brain, is among the factors contributing to the AED resistance. Presently, there is no consensus on the interaction of carbamazepine (CBZ) with the Pgp. This study investigates the effect of the Pgp inhibitor verapamil on the anticonvulsant effect of CBZ and its nanoparticulate formulation in the rat model of isoniazid-induced epilepsy. Verapamil significantly increased the anticonvulsant effect of CBZ and reduced its effective dose by at least 30% (from 30 mg/kg to 20 mg/kg). Binding of carbamazepine to the poloxamer 188-coated PLGA nanoparticles enabled a 30-fold increase of its anticonvulsive effect, as compared to the free drug. The inhibition of Pgp did not influence the effectivity of carbamazepine encapsulated in nanoparticles.


Asunto(s)
Anticonvulsivantes/administración & dosificación , Carbamazepina/administración & dosificación , Epilepsia Refractaria/tratamiento farmacológico , Nanopartículas/administración & dosificación , Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/antagonistas & inhibidores , Animales , Anticonvulsivantes/química , Anticonvulsivantes/farmacocinética , Anticonvulsivantes/uso terapéutico , Encéfalo/fisiopatología , Carbamazepina/química , Carbamazepina/farmacocinética , Carbamazepina/uso terapéutico , Relación Dosis-Respuesta a Droga , Sistemas de Liberación de Medicamentos , Epilepsia Refractaria/inducido químicamente , Epilepsia Refractaria/fisiopatología , Electrocorticografía , Isoniazida , Ácido Láctico/administración & dosificación , Ácido Láctico/química , Ácido Láctico/farmacocinética , Ácido Láctico/uso terapéutico , Masculino , Nanopartículas/química , Nanopartículas/uso terapéutico , Poloxámero/administración & dosificación , Poloxámero/química , Poloxámero/farmacocinética , Poloxámero/uso terapéutico , Ácido Poliglicólico/administración & dosificación , Ácido Poliglicólico/química , Ácido Poliglicólico/farmacocinética , Ácido Poliglicólico/uso terapéutico , Copolímero de Ácido Poliláctico-Ácido Poliglicólico , Ratas Wistar , Verapamilo/farmacología
19.
Phys Rev E Stat Nonlin Soft Matter Phys ; 75(3 Pt 1): 031101, 2007 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-17500662

RESUMEN

The anomalous translational diffusion including inertial effects of nonlinear Brownian oscillators in a double well potential V(x)=ax{2}/2+bx{4}/4 is considered. An exact solution of the fractional Klein-Kramers (Fokker-Planck) equation is obtained allowing one to calculate via matrix continued fractions the positional autocorrelation function and dynamic susceptibility describing the position response to a small external field. The result is a generalization of the solution for the normal Brownian motion in a double well potential to fractional dynamics (giving rise to anomalous diffusion).

20.
Ultrasonics ; 44(2): 182-7, 2006 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-16376398

RESUMEN

A new method of measuring velocity and attenuation of leaky surface waves is presented. A single focused transmitting transducer and linear receiving array in a pitch-catch arrangement are used in the proposed system. The spatial distribution of the acoustic field in the leaky wave is recorded by the array, and the parameters of the leaky wave can be obtained by processing the output waveforms. In comparison with existing material characterization systems, the mechanical scanning of the transducers is not used any more, and the measurement time is only limited by the time of the wave propagation and speed of the electronic data acquisition system.

SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA