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1.
Neuron ; 110(20): 3318-3338.e9, 2022 10 19.
Artigo em Inglês | MEDLINE | ID: mdl-36265442

RESUMO

Brain tissue transcriptomes may be organized into gene coexpression networks, but their underlying biological drivers remain incompletely understood. Here, we undertook a large-scale transcriptomic study using 508 wild-type mouse striatal tissue samples dissected exclusively in the afternoons to define 38 highly reproducible gene coexpression modules. We found that 13 and 11 modules are enriched in cell-type and molecular complex markers, respectively. Importantly, 18 modules are highly enriched in daily rhythmically expressed genes that peak or trough with distinct temporal kinetics, revealing the underlying biology of striatal diurnal gene networks. Moreover, the diurnal coexpression networks are a dominant feature of daytime transcriptomes in the mouse cortex. We next employed the striatal coexpression modules to decipher the striatal transcriptomic signatures from Huntington's disease models and heterozygous null mice for 52 genes, uncovering novel functions for Prkcq and Kdm4b in oligodendrocyte differentiation and bipolar disorder-associated Trank1 in regulating anxiety-like behaviors and nocturnal locomotion.


Assuntos
Doença de Huntington , Transcriptoma , Animais , Camundongos , Proteína Quinase C-theta/genética , Redes Reguladoras de Genes , Doença de Huntington/genética , Encéfalo
2.
Environ Sci Pollut Res Int ; 28(10): 12714-12724, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33094459

RESUMO

We studied the impact of fly ash produced by the thermal power station in the Middle Urals (Russia) on functional traits of two Betula species naturally colonizing ash dump lagoons. The main limiting factors for tree growth on fly ash deposits were nitrogen deficiency, high alkalinity, and unfavorable mechanical composition of substrate. Leaf area ratio (LAR) and leaf mass ratio (LMR) per tree, leaf area (LA), leaf shape coefficient (LSh), leaf thickness (LT), leaf mass per area (LMA), photosynthesis (Amax) and transpiration rates, chlorophyll (Chl), carotenoid (Car), and nitrogen (N) content were measured in Betula pendula Roth and Betula pubescens Ehrh. growing on the ash dump and in the forest near the dump. Both Betula species showed similar functional response to adverse conditions of the fly ash. We found a 1.5-2-fold increase in LAR and LMR in trees growing on fly ash deposits compared with trees in the forest. In both species, the most significant differences across leaf morphological traits were shown for LT. Higher LT provided an increase in Chl and N content per leaf area that caused the rise in Amax and photosynthetic water use efficiency in the trees on the ash deposit. At the same time, Betula species preserved interspecific differences in values of LA and LT which were larger in B. pubescens whiles B. pendula differed by higher LSh. We concluded that the increase in assimilation activity at both whole-plant and leaf levels provides plant adjustment to edaphic and nutrient stress that allow Betula species to colonize technogenic substrates as fly ash deposits.


Assuntos
Betula , Cinza de Carvão , Nutrientes , Fotossíntese , Folhas de Planta , Federação Russa , Árvores
3.
Oxid Med Cell Longev ; 2019: 8549727, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31565155

RESUMO

The overexposure to nickel due to the extensive use of it in modern technology remains a major public health concern. The mechanisms of pathological effects of this metal remain elusive. The present study was devoted to evaluate the effect of nickel on the oxidative state of the brain cells of mice and to assess whether zinc as redox state modulator could efficiently protect cells against nickel's neurotoxicity. As oxidative stress biomarkers in the present study, we have measured the concentrations of reduced glutathione, metallothioneins, and malondialdehyde and the activity of the enzyme δ-aminolevulinate dehydratase. For the single metal exposure, mice were i.p. injected once with solutions of NiCl2 and/or ZnSO4; repeated exposure was performed i.p. injecting metal salt solutions for 14 days (once a day). The control mice received i.p. injections of saline. Results of our study demonstrate that single and 14 days of Ni2+ exposure decreased reduced glutathione and increased malondialdehyde contents in the brain of mice. Repeated Ni2+ administration significantly inhibited δ-aminolevulinate dehydratase while increasing brain metallothionein concentration at both exposure periods. Zinc exhibited a protective effect against nickel-induced glutathione and lipid peroxidation in brain cells of mice at both intervals of time, while repeated exposure to this metal significantly raised the brain metallothionein content. Repeated Zn2+ pretreatment protected δ-aminolevulinate dehydratase from Ni2+-induced inhibition and significantly increased metallothionein concentration at both investigated time intervals.


Assuntos
Biomarcadores/química , Encéfalo/efeitos dos fármacos , Níquel/efeitos adversos , Estresse Oxidativo/efeitos dos fármacos , Zinco/uso terapêutico , Animais , Camundongos , Zinco/farmacologia
4.
Virus Res ; 272: 197717, 2019 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-31422116

RESUMO

Insectivores are the new emerging reservoir of hantaviruses. Here, we describe Lena virus (LENV), a novel hantavirus harbored by the Laxmann`s shrew (Sorex caecutiens), which is also the host of Artybash virus (ARTV). Genetic analysis of the complete genomic sequence shows that LENV is in distant relation to ARTV and other Sorex-borne hantaviruses, suggesting that LENV has emerged from cross-species transmission. Additionally, new genetic variant of ARTV, designated as ARTV-St, was identified in tundra shrews (Sorex tundrensis). Finally, distinct insectivore-borne hantaviruses are co-circulating in the same localities of far eastern Russia: LENV, ARTV and Yakeshi in the forest site, while ARTV, ARTV-St, and Kenkeme virus in the meadow field site.


Assuntos
Infecções por Hantavirus/epidemiologia , Infecções por Hantavirus/virologia , Orthohantavírus , Musaranhos/virologia , Animais , Ásia Oriental , Genoma Viral , Orthohantavírus/classificação , Orthohantavírus/genética , Orthohantavírus/isolamento & purificação , Infecções por Hantavirus/transmissão , Filogenia , Reação em Cadeia da Polimerase , Prevalência , Vigilância em Saúde Pública , RNA Viral , Federação Russa/epidemiologia
5.
Int J Parasitol Parasites Wildl ; 8: 192-202, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30891399

RESUMO

Borrelia burgdorferi sensu lato (s.l.) DNA was detected by PCR in Ixodes persulcatus Schulze, 1930, Haemaphysalis concinna Koch, 1844, Haemaphysalis japonica douglasi Nuttall et Warburton, 1915 and Dermacentor silvarum Olenev, 1932 ticks collected in the Amur region, the Jewish Autonomous region, the Sakhalin region and on the Khabarovsk territory. Infection rate of I. persulcatus with B. burgdorferi s.l. 10-69% exceeded the corresponding values of three other tick species in all examined regions during 1999-2014 despite different tick abundance and dominance structure. Bacterial loads estimated on the base of quantitative real time PCR varied from 102 to 109 genome-equivalents per a tick with maximal values for I. persulcatus and H. japonica. Phylogenetic analysis of 16S rRNA gene and 5S-23S rRNA intergenic spacer nucleotide sequences revealed two species: 1) Borrelia garinii of Asian type NT29 with several isolates of European type 20047; 2) Borrelia afzelii with identical sequences of the majority of studied isolates and VS461 reference strain in all regions except the Sakhalin Island where B. afzelii was not found. Borrelia miyamotoi of the relapsing fever group was detected as monoinfection or in combination with B. burgdorferi s.l. in 4.0 ±â€¯0.9% and 4.8 ±â€¯0.9% I. persulcatus ticks, respectively. Multiple locus sequence analysis of three fragments of 16S rRNA, glpQ and p66 genes proved that all the Far Eastern B. miyamotoi isolates belonged to the Asian type identical to FR64b strain (GenBank CP004217) from Japan. Wide distribution of Borrelia DNA in ticks, relative genetic homogeneity with similar sequences of the coding regions and the intergenic spacer of Borrelia wild isolates and temporal stability with high homology levels of the Far Eastern isolates of B. garinii, B. afzelii and B. miyamotoi with previously described spirochetes from the surrounding regions of Russia, China and Japan allowed us to suggest multiple ecological niches as the stability factor of the parasitic system.

6.
Ticks Tick Borne Dis ; 9(6): 1594-1603, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30121164

RESUMO

The Russian Far East is an endemic region for tick-borne rickettsioses. However, the prevalence and genetic variability of Rickettsia species in this region have not been extensively investigated. In this study, 188 Dermacentor silvarum, 439 Haemaphysalis concinna, and 374 Haemaphysalis japonica adult ticks were collected from four locations in Khabarovsk Province and three locations in Amur Province in the Russian Far East. These ticks were examined for the presence of Rickettsia spp. by amplifying a fragment of the gltA gene. Identified rickettsiae were genotyped by sequencing of the gltA, 16S rRNA, ompA, ompB, and sca4 genes. In the examined ticks, Rickettsia heilongjiangensis, the causative agent of Far-Eastern tick-borne rickettsiosis, was found in 10.5% of H. concinna and in 1.9% of H. japonica ticks, while Rickettsia sibirica, the agent of Siberian tick typhus, was detected in only one H. concinna tick. In addition, Rickettsia raoultii was found predominantly in D. silvarum (>70%) and significantly less frequently in Haemaphysalis ticks (<3%). "Candidatus Rickettsia tarasevichiae" was found in all examined tick species (1.6-5.3% in different species). Notably, this study is the first observation of "Candidatus R. tarasevichiae" in D. silvarum ticks. Moreover, DNA of Rickettsia canadensis was found for the first time in a H. japonica tick; DNA of Rickettsia aeschlimannii was revealed for the first time in H. concinna and H. japonica ticks. "Candidatus Rickettsia principis" and "Candidatus Rickettsia rara" were found in Haemaphysalis spp. ticks. "Candidatus R. principis" was associated with H. japonica and identified in 5.6% of the examined ticks, while "Candidatus R. rara" was found more frequently in H. concinna (3.0%) compared to H. japonica ticks (1.1%). In this study, "Candidatus R. principis" and "Candidatus R. rara" were characterized for the first time by the 16S rRNA, ompA, ompB, and sca4 genes.


Assuntos
Variação Genética , Ixodidae/microbiologia , Rickettsia/genética , Animais , Dermacentor/crescimento & desenvolvimento , Dermacentor/microbiologia , Feminino , Ixodidae/crescimento & desenvolvimento , Larva/microbiologia , Masculino , Ninfa/microbiologia , Rickettsia/fisiologia , Sibéria
7.
Ticks Tick Borne Dis ; 9(4): 824-833, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29555424

RESUMO

Isolates of tick-borne encephalitis virus (TBEV) from arthropod vectors (ticks and mosquitoes) in the Amur, the Jewish Autonomous and the Sakhalin regions as well as on the Khabarovsk territory of the Far East of Russia were studied. Different proportions of four main tick species of the family Ixodidae: Ixodes persulcatus P. Schulze, 1930; Haemaphysalis concinna Koch, 1844; Haemaphysalis japonica douglasi Nuttall et Warburton, 1915 and Dermacentor silvarum Olenev, 1932 were found in forests and near settlements. RT-PCR of TBEV RNA in adult ticks collected from vegetation in 1999-2014 revealed average infection rates of 7.9 ±â€¯0.7% in I. persulcatus, of 5.6 ±â€¯1.0% in H. concinna, of 2.0 ±â€¯2.0% in H. japonica, and of 1.3 ±â€¯1.3% in D. silvarum. Viral loads varied in a range from 102 to 109 TBEV genome-equivalents per a tick with the maximal values in I. persulcatus and H. japonica. Molecular typing using reverse transcription with subsequent real time PCR with subtype-specific fluorescent probes demonstrated that the Far Eastern (FE) subtype of TBEV predominated both in mono-infections and in mixed infection with the Siberian (Sib) subtype in I. persulcatus pools. TBEV strains of the FE subtype were isolated from I. persulcatus, H. concinna and from a pool of Aedes vexans mosquitoes. Ten TBEV strains isolated from I. persulcatus from the Khabarovsk territory and the Jewish Autonomous region between 1985 and 2013 cluster with the TBEV vaccine strain Sofjin of the FE subtype isolated from human brain in 1937. A TBEV strain from H. concinna collected in the Amur region (GenBank accession number KF880803) is similar to the vaccine strain 205 isolated in 1973 from I. persulcatus collected in the Jewish Autonomous region. The TBEV strain Lazo MP36 of the FE subtype isolated from a pool of A. vexans in the Khabarovsk territory in 2014 (KT001073) differs from strains isolated from 1) I. persulcatus (including the vaccine strain 205) and H. concinna; 2) mosquitoes [strain Malishevo (KJ744034) isolated in 1978 from Aedes vexans nipponii in the Khabarovsk territory]; and 3) human brain (including the vaccine strain Sofjin). Accordingly, in the far eastern natural foci, TBEV of the prevailing FE subtype has remained stable since 1937. Both Russian vaccines against TBE based on the FE strains (Sofjin and 205) are similar to the new viral isolates and might protect against infection.


Assuntos
Aedes/virologia , Vetores Artrópodes/virologia , Dermacentor/virologia , Vírus da Encefalite Transmitidos por Carrapatos/isolamento & purificação , Encefalite Transmitida por Carrapatos/epidemiologia , Ixodidae/virologia , Animais , Vírus da Encefalite Transmitidos por Carrapatos/genética , Encefalite Transmitida por Carrapatos/virologia , Florestas , Genoma Viral , Ixodes/virologia , Tipagem Molecular , Filogenia , Reação em Cadeia da Polimerase em Tempo Real , Federação Russa
8.
New Phytol ; 217(2): 558-570, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29053190

RESUMO

We studied the impact of aridity on leaf and mesophyll traits in dominant and very abundant plant species of Eurasian steppe plant communities. We covered a 500-km latitudinal gradient across three vegetation zones in the Volga region of southern European Russia. Whole-leaf traits, volumetric fractions of leaf tissues, quantitative parameters of photosynthetic cells and chloroplasts, and chlorophyll, carbon (C) and nitrogen (N) contents were analyzed and related to plant functional type (PFT), type of mesophyll anatomy, phylogeny and climate aridity. The proportions of prevailing PFTs in the communities, such as C3 monocots, C3 dicots with dorsiventral and isopalisade anatomy and C4 dicots, changed with increasing aridity which influenced the whole-leaf parameters and tissue composition in the leaf. Leaf mass per unit area and leaf thickness slightly increased along the aridity gradient, but the most significant changes were observed in the mesophyll. Mesophyll cell surface area, chloroplast number and chloroplast surface area per unit leaf area were higher in C3 plants growing in the desert steppe compared with those of the forest steppe, while chlorophyll content per single chloroplast and per unit N content as well chlorophyll a/b ratio decreased. Our results identify a suite of mesophyll traits as a typical 'syndrome' of increasingly drought-adapted steppe plants.


Assuntos
Carbono/metabolismo , Secas , Pradaria , Células do Mesofilo/metabolismo , Característica Quantitativa Herdável , Clima , Análise de Componente Principal
9.
Melanoma Res ; 27(1): 32-42, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27824739

RESUMO

Skin cancer affects more individuals in the USA than any other malignancy and malignant melanoma is particularly deadly because of its metastatic potential. Melanoma has been recognized as one of the most immunogenic malignancies; therefore, understanding the mechanisms of tumor-immune interaction is key for developing more efficient treatments. As the tumor microenvironment shows an immunosuppressive action, immunotherapeutic agents promoting endogenous immune response to cancer have been tested (interleukin-2, anticytotoxic-T-lymphocyte-associated antigen 4, and antiprogrammed cell death protein 1 monoclonal antibodies) as well as combinations of cytotoxic chemotherapy agents and inhibitors of angiogenesis (taxol/carboplatin/avastin). However, clinical outcomes are variable, with only a minority of patients achieving durable complete responses. The variability of immune homeostasis, which may be more active or more tolerant at any given time, in cancer patients and the interaction of the immune system with the tumor could explain the inconsistency in clinical outcomes among these patients. Recently, the role of the lymphocyte-to-monocyte-ratio (LMR) in the peripheral blood has been investigated and has been proven to be an independent predictor of survival in different hematological malignancies and in solid tumors. In melanoma, our group has validated the significance of LMR as a predictor of relapse after resection of advanced melanoma. In this study, we examined the dynamics in the immune system of patients with advanced melanoma by performing serial multiday concentration measurements of cytokines and immune cell subsets in the peripheral blood. The analysis of outcomes of chemotherapy administration as related to LMR on the day of treatment initiation showed that progression-free survival was improved in the patients who received chemotherapy on the day when LMR was elevated.


Assuntos
Antineoplásicos Alquilantes/administração & dosagem , Dacarbazina/análogos & derivados , Linfócitos , Melanoma/sangue , Melanoma/tratamento farmacológico , Monócitos , Neoplasias Cutâneas/sangue , Neoplasias Cutâneas/tratamento farmacológico , Adulto , Idoso , Idoso de 80 Anos ou mais , Algoritmos , Antígeno CD11c/metabolismo , Complexo CD3/metabolismo , Antígenos CD4/metabolismo , Dacarbazina/administração & dosagem , Intervalo Livre de Doença , Esquema de Medicação , Feminino , Humanos , Receptores de Lipopolissacarídeos/metabolismo , Contagem de Linfócitos , Linfócitos/metabolismo , Masculino , Melanoma/imunologia , Pessoa de Meia-Idade , Estudos Retrospectivos , Neoplasias Cutâneas/imunologia , Temozolomida , Fatores de Tempo , Resultado do Tratamento
10.
Int J Mol Sci ; 17(7)2016 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-27447613

RESUMO

A multivitamin and mineral supplementation study of 6 weeks was conducted with male and female mice. The control group received a standard dose of vitamins and minerals of 1× the Recommended Daily Intake (RDI), whereas a second group received 3× RDI. A third group received a high dose of vitamin E (25× RDI), close to the upper limit of toxicity (UL), but still recommended and considered to be harmless and beneficial. The high dose of vitamin E caused a number of beneficial, but also adverse effects. Different biomarkers of tissue toxicity, oxidative stress related processes and inflammation were determined. These biomarkers did not change in plasma and erythrocytes to a large extent. In the liver of male mice, some beneficial effects were observed by a lower concentration of several biomarkers of inflammation. However, in the kidney of male mice, a number of biomarkers increased substantially with the higher dose of vitamin E, indicating tissue toxicity and an increased level of inflammation. Since this dose of vitamin E, which is lower than the UL, cause some adverse effects, even after a short exposure period, further studies are required to reconsider the UL for vitamin E.


Assuntos
Antioxidantes/farmacologia , Suplementos Nutricionais , Inflamação/induzido quimicamente , Rim/efeitos dos fármacos , Fígado/efeitos dos fármacos , Vitamina E/farmacologia , Animais , Sobrevivência Celular/efeitos dos fármacos , Feminino , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Especificidade de Órgãos
11.
J Toxicol Environ Health A ; 77(21): 1311-8, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25268558

RESUMO

Exposure to cadmium (Cd) is known to alter immune responses. Acanthopanax senticosus (Rupr. et Maxim.) Harms (AS) extract, an antioxidant-containing complex of phenolic compounds, tetracyclic triterpenoids/steroids, and polysaccharides, is known to produce Cd mobilization and excretion in vivo. Building upon earlier findings, the aim of the study was to evaluate the effects of an AS extract on Cd accumulation and changes in the presence of splenic immune cells in hosts during a chronic metal exposure. Chronic Cd exposure of BALB/c mice was induced by providing them solutions containing different levels of CdCl2 (25 or 250 mg/L) in double-distilled water, with/without a concurrent presence of AS root extract (approximately 151 g material/L), for 8 wk. At the study end, Cd levels in spleen were measured. Levels of key splenic immune cells, including macrophages, T-lymphocytes, and B-lymphocytes, were determined by immunohistochemistry using, respectively, CD68, CD3, and CD20 antibodies. The results indicated that chronic consumption of AS extract in the presence of the high dose of CdCl2 led to a significant decrease in Cd levels in mouse spleen. The effects of AS on the lower CdCl2 dose were less apparent. In addition, the presence of AS and Cd increased the amount of macrophages and both B and T lymphocytes in mouse spleen relative to concentrations that were lowered as a result of chronic metal only intake.


Assuntos
Cloreto de Cádmio/farmacocinética , Cloreto de Cádmio/toxicidade , Eleutherococcus/química , Extratos Vegetais/farmacologia , Baço/efeitos dos fármacos , Baço/imunologia , Animais , Linfócitos B/efeitos dos fármacos , Linfócitos B/metabolismo , Relação Dose-Resposta a Droga , Imuno-Histoquímica , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Raízes de Plantas/química , Baço/citologia , Linfócitos T/efeitos dos fármacos , Linfócitos T/metabolismo
12.
Environ Toxicol Pharmacol ; 36(3): 1261-5, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24211594

RESUMO

The study aimed at evaluating the effects of cadmium and selenite ions on protein synthesis and metallothioneins content in mice liver after 2 h, 8 h, 24 h and 14 days of exposure. Our studies revealed that cadmium suppressed protein synthesis after 2 h and 24 h, but activated after 8h and 14 days. Also, the endogenous mRNA translation were reduced under any exposure to cadmium, meanwhile, metallothioneins content was decreased after 2 h, but then was progressively increasing up to 492% after 14 days. Meantime, selenite did not influence metallothioneins content, caused mild activation of protein synthesis, and slightly suppressed the endogenous mRNA translation. The combined treatments with cadmium and selenite favored toward resisting of protein synthesis to cadmium after 2 h and 24 h of intoxication. Besides, selenite also protected translation against cadmium in cell-free systems, but did not attenuate effects of cadmium on metallothioneins content.


Assuntos
Cloreto de Cádmio/toxicidade , Fígado/metabolismo , Biossíntese de Proteínas/efeitos dos fármacos , Selenito de Sódio/toxicidade , Animais , Sistema Livre de Células , Fígado/efeitos dos fármacos , Metalotioneína/genética , Metalotioneína/metabolismo , Camundongos , RNA Mensageiro/biossíntese , RNA Mensageiro/genética
13.
J Trace Elem Med Biol ; 27(3): 226-9, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23219369

RESUMO

In this study the acute toxic effects of aluminum (Al) on mice have been investigated, including the interactions of Al and selenium (Se). Focus was put on the systemic effects of (co)exposure to Al and Se as a reflection of the redox status in the liver, kidney and brain. Short-term exposure (16 h) to Al resulted in an increase in the systemic inflammation parameters IL-6 and PAI-1, whereas serum levels of TNF-α remained unaffected. The different response pattern of IL-6 and TNF-α probably indicates an increased intracellular oxidative stress and altered redox status in the liver, because the selective increase in IL-6 serves as a protective intrahepatocellular process driven by oxidative stress. The intracellular glutathione concentration GSHtot decreased significantly upon Al exposure. Both the increase in IL-6 and decrease in glutathione status could be prevented by co-exposure to Se, but not the increase in PAI-1. The redox status of the kidney and brain was not markedly affected. Therefore it was concluded that short-term exposure to Al causes adverse effects on the intracellular oxidative stress processes in the liver, as reflected by the selective increase in the IL-6 concentration. This process can be restored by co-administration of the trace element Se as a part of the glutathione redox system.


Assuntos
Compostos de Alumínio/farmacologia , Cloretos/farmacologia , Interleucina-6/biossíntese , Estresse Oxidativo/efeitos dos fármacos , Selenito de Sódio/farmacologia , Cloreto de Alumínio , Compostos de Alumínio/administração & dosagem , Animais , Cloretos/administração & dosagem , Camundongos , Camundongos Endogâmicos BALB C , Oxirredução/efeitos dos fármacos , Selenito de Sódio/administração & dosagem
14.
Acta Crystallogr B ; 68(Pt 5): 543-8, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22992799

RESUMO

BNC nanotubes and nanofibers have been synthesized in the high isostatic pressure apparatus in Ar at 1923 K and 1.5 MPa in the presence of yttrium aluminium garnet. Some of the nanotubes obtained were filled with Al(2)O(3). Transmission electron microscopy (TEM) studies have shown that the nanotubes and nanofibers have a polygonal cross-section (prismatic shape), and most often they are twisted, which is due to the transversal instability of the nanotubes originating under the growth conditions, including temperature treatment. Twisting also revealed itself in the appearance of the moiré fringes during the TEM observation of some of the nanotubes and nanofibers. Analysis of these fringes has shown that the facets of these nanotubes represent the slightly misoriented hexagonal BN and/or C plates. An Al(2)O(3) filling of the nanotube makes it harder to twist when subjected to torque, which conforms to the tube deformation theory.

15.
J Vet Med Sci ; 74(9): 1237-42, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22673703

RESUMO

Antigenic diversity among different hantaviruses requires a variety of reagents for diagnosis of hantavirus infection. To develop a diagnostic method applicable to various hantavirus infections with a single set of reagents, we developed an enzyme-linked immunosorbent assay (ELISA) using recombinant nucleocapsid proteins of three hantaviruses, Amur, Hokkaido, and Sin Nombre viruses. This novel cocktail antigen-based ELISA enabled detection of antibodies against Hantaan, Seoul, Amur, Puumala, and Sin Nombre viruses in immunized laboratory animals. In wild rodent species, including Apodemus, Rattus, and Myodes, our ELISA detected antibodies against hantaviruses with high sensitivity and specificity. These data suggest that our novel diagnostic ELISA is a useful tool for screening hantavirus infections and could be effectively utilized for serological surveillance and quarantine purposes.


Assuntos
Arvicolinae , Ensaio de Imunoadsorção Enzimática/veterinária , Infecções por Hantavirus/veterinária , Murinae , Orthohantavírus/genética , Ratos , Doenças dos Roedores/diagnóstico , Doenças dos Roedores/virologia , Animais , Anticorpos Antivirais/isolamento & purificação , Ensaio de Imunoadsorção Enzimática/métodos , Infecções por Hantavirus/diagnóstico , Infecções por Hantavirus/imunologia , Proteínas do Nucleocapsídeo/genética , Proteínas Recombinantes/genética , Doenças dos Roedores/imunologia , Sensibilidade e Especificidade , Testes Sorológicos/veterinária , Especificidade da Espécie
16.
Am J Trop Med Hyg ; 86(3): 545-53, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22403334

RESUMO

Hemorrhagic fever with renal syndrome (HFRS) is a serious public health issue in Far East Russia. Two different hantaviruses were isolated from rodents captured in the Khabarovsk region: Amur virus (AMRV; Khekhtsir/AP209/2005 strain from Apodemus peninsulae) and Hantaan virus (HTNV; Galkino/AA57/2002 strain from A. agrarius). Genetic analysis of the new isolates revealed that the M and L segments were apparently different between AMRV and HTNV, but S segments of the two viruses were closer. The antigenicities of AMRV, HTNV, and Seoul virus (SEOV) were differentiated by cross-neutralization. Serological differential diagnoses of 67 HFRS patients in the Prymorsky and Khabarovsk regions of Far East Russia were conducted using a neutralization test. The results revealed that the major cause of HFRS varied with location in Far East Russia: SEOV for Vladivostok city in the Prymorsky region, AMRV in rural areas of the Primorsky region, and probably HTNV for the Khabarovsk region.


Assuntos
DNA Viral/genética , Vírus Hantaan/isolamento & purificação , Febre Hemorrágica com Síndrome Renal/virologia , Murinae/virologia , Vírus Seoul/isolamento & purificação , Animais , Anticorpos Antivirais/sangue , Vírus Hantaan/genética , Vírus Hantaan/patogenicidade , Febre Hemorrágica com Síndrome Renal/diagnóstico , Febre Hemorrágica com Síndrome Renal/fisiopatologia , Humanos , Filogenia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Vírus Seoul/genética , Vírus Seoul/patogenicidade , Análise de Sequência de DNA
17.
Front Biosci (Elite Ed) ; 4(3): 958-75, 2012 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-22201928

RESUMO

Evidence suggests that immunological response in chronic inflammation is dynamic, oscillating between active immunity and tolerance. We hypothesized that a similar dynamic exists in melanoma and administration of therapy during a unique phase of such oscillation could impact clinical outcome. Patients with metastatic melanoma eligible to undergo temozolomide underwent serial measurements of C-reactive protein (CRP) and immune biomarkers every 2-3 days for 2 weeks before starting therapy. Treatment was initiated prior to the estimated next CRP peak, or on day 14 post-registration if a peak was not identified. Time profiles of measured biomarkers were analyzed by fitting serially measured data points to 9 mathematical functions and were correlated to time of therapy and outcome. Data suggested that metastatic melanoma patients exhibit a dynamic immune response. The fluctuation of several biomarkers fitted cosine functions with periods which were multiples of 3-4 days. Chemotherapy delivery during a unique phase of this cycle seemed to correlate with improved response. Individualized conventional chemotherapy delivery by synchronizing treatment with pre-existing patient-specific biorhythms may improve clinical outcomes in metastatic melanoma.


Assuntos
Melanoma/imunologia , Adulto , Idoso , Citocinas/sangue , Feminino , Humanos , Imunofenotipagem , Masculino , Melanoma/terapia , Pessoa de Meia-Idade , Resultado do Tratamento
18.
Environ Toxicol Pharmacol ; 31(2): 302-6, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21787698

RESUMO

The aim of the study was to evaluate possible protective effects of selenium (Se) against systemic aluminium (Al) toxicity and the redox status of mouse liver after short-term (16 h) exposure to Al in vivo. BALB/c mice were injected i.p. with AlCl(3) (25mg Al(3+) per kg of body mass) or/and Na(2)SeO(3) (1.25mg Se per kg of body mass). The 4-fold increased activity of ALT in serum showed systemic hepatotoxicity that Se could not prevent by competitive mechanisms. The protective effects of Se could only be observed on intracellular oxidative stress events as determined by glutathione status. Exposure to Al leads to the decrease in the total glutathione (GSH(tot)) and GSH/GSSG redox ratio to about 50% of the control. Upon co-exposure to Se+Al, the concentration of GSH(tot) and the redox ratio was restored to the control values. Our results indicate that Se did not have a protective effect on Al-linked liver toxicity, but did ameliorate intracellular oxidative stress processes mediated by glutathione.


Assuntos
Alumínio/toxicidade , Antioxidantes/farmacologia , Fígado/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Selênio/farmacologia , Alanina Transaminase/sangue , Animais , Glutationa/metabolismo , Dissulfeto de Glutationa/metabolismo , Fígado/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C
19.
Vector Borne Zoonotic Dis ; 11(8): 1013-21, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21612528

RESUMO

The specimens of 3552 questing adult Ixodes persulcatus and 1698 blood/tissue samples of small mammals collected in Ural, Siberia, and Far East of Russia were assayed for the presence of Anaplasma phagocytophilum by nested PCR based on the 16S rRNA gene. Totally, A. phagocytophilum was detected in 112 tick and 88 mammalian samples. The nucleotide sequences of the 16S rRNA gene and groESL operon (1244-1295 bp) were determined for A. phagocytophilum samples from 65 ticks and 25 small mammals. Six different 16S rRNA gene variants differing by 1-5 nucleotide substitutions were detected, and only one variant matched the sequences deposited in GenBank. Analysis of groESL sequences allowed the A. phagocytophilum samples to be divided into three groups; moreover, the samples from different groups also differed in the 16S rRNA gene sequences. The A. phagocytophilum sequences from group I were detected in 11 Myodes spp. samples from West Siberia and Far East and in 19 I. persulcatus samples from all examined regions; from group II, in 10 samples of Myodes spp. and common shrews (Sorex araneus) from Ural; and from group III, in four samples of Asian chipmunks (Tamias sibiricus) from West Siberia and Far East; and in 46 I. persulcatus samples from all examined regions. The nucleotide sequences of A. phagocytophilum groESL operon from groups I and II were strictly conserved and formed with A. phagocytophilum groESL sequence from a Swiss bank vole (Myodes glareolus) (GenBank accession no. AF192796), a separate cluster on the phylogenetic tree with a strong bootstrap support. The A. phagocytophilum groESL operon sequences from group III differed from one another by 1-4 nucleotides and formed a separate branch in the cluster generated by European A. phagocytophilum strains from roe deer (Capreolus capreolus) and Ixodes ricinus ticks.


Assuntos
Anaplasma phagocytophilum/genética , Eulipotyphla/microbiologia , Ixodes/microbiologia , Anaplasma phagocytophilum/isolamento & purificação , Animais , Proteínas de Bactérias/genética , Chaperoninas/genética , Bases de Dados de Ácidos Nucleicos , Ehrlichiose/epidemiologia , Reação em Cadeia da Polimerase , RNA Ribossômico 16S , Federação Russa/epidemiologia , Análise de Sequência
20.
Am J Trop Med Hyg ; 84(3): 461-5, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21363987

RESUMO

West Nile (WN) virus has been spreading geographically to non-endemic areas in various parts of the world. However, little is known about the extent of WN virus infection in Russia. Japanese encephalitis (JE) virus, which is closely related to WN virus, is prevalent throughout East Asia. We evaluated the effectiveness of a focus reduction neutralization test in young chicks inoculated with JE and WN viruses, and conducted a survey of WN infection among wild birds in Far Eastern Russia. Following single virus infection, only neutralizing antibodies specific to the homologous virus were detected in chicks. The neutralization test was then applied to serum samples from 145 wild birds for WN and JE virus. Twenty-one samples were positive for neutralizing antibodies to WN. These results suggest that WN virus is prevalent among wild birds in the Far Eastern region of Russia.


Assuntos
Doenças das Aves/epidemiologia , Testes de Neutralização/veterinária , Febre do Nilo Ocidental/veterinária , Vírus do Nilo Ocidental/isolamento & purificação , Animais , Animais Selvagens , Anticorpos Neutralizantes/sangue , Anticorpos Antivirais/sangue , Doenças das Aves/sangue , Doenças das Aves/virologia , Aves , Vírus da Encefalite Japonesa (Espécie)/genética , Encefalite Japonesa/epidemiologia , Encefalite Japonesa/veterinária , Masculino , Testes de Neutralização/métodos , Federação Russa/epidemiologia , Viremia , Febre do Nilo Ocidental/sangue , Febre do Nilo Ocidental/epidemiologia , Febre do Nilo Ocidental/virologia , Vírus do Nilo Ocidental/classificação
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