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1.
J Physiol Pharmacol ; 69(6)2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30802219

RESUMO

Toxicological studies are urgently needed to confirm the safety of Sophora japonica extracts for clinical use. In particular, in addition to pharmacy and pharmacology, phytotherapy, herbal medication, Sophora japonica extracts are widely used as biologically active supplements. Scientfic data suggests that some of Sophora japonica extract components have very comprehensive biological effects. In the present study, our hypothesis assumed the potential reprotoxicity of Sophora japonica extract in respect to mouse germ cells (GC-1 spg, GC-2 spd) in vitro. Specifically, we were interested in the high-performance liquid chromatography (HPLC) identification of extract components and its stress-related effects on cellular and biochemical features, such as mitochondrial metabolism, cell cycle progression, oxidative stress balance and micronuclei formation. The results indicate that Sophora japonica extract induces oxidative/nitrosative stress-mediated impairment of the mechanism for free radicals scavenging, which may provoke genotoxic events in germ cells, by cell cycle arrest and micronuclei formation. Therefore, the interplay between reactive oxygen species (ROS)/reactive nitrogen species (RNS) and antioxidant system is critical for normal testicular function maintenance in the their environment. The specific pathways and mechanisms involved in the reprotoxicity of Sophora japonica need to be further investigated.


Assuntos
Células Germinativas/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Extratos Vegetais/toxicidade , Sophora/química , Animais , Antioxidantes/metabolismo , Ciclo Celular/efeitos dos fármacos , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão/métodos , Células Germinativas/patologia , Masculino , Camundongos , Testes para Micronúcleos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Testes de Mutagenicidade , Estresse Nitrosativo/efeitos dos fármacos , Espécies Reativas de Nitrogênio/metabolismo , Espécies Reativas de Oxigênio/metabolismo
2.
Neurobiol Dis ; 80: 42-53, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25986729

RESUMO

Autism spectrum disorders are severe neurodevelopmental disorders, marked by impairments in reciprocal social interaction, delays in early language and communication, and the presence of restrictive, repetitive and stereotyped behaviors. Accumulating evidence suggests that dysfunction of the amygdala may be partially responsible for the impairment of social behavior that is a hallmark feature of ASD. Our studies suggest that a valproic acid (VPA) rat model of ASD exhibits an enlargement of the amygdala as compared to controls rats, similar to that observed in adolescent ASD individuals. Since recent research suggests that altered neuronal development and morphology, as seen in ASD, may result from a common post-transcriptional process that is under tight regulation by microRNAs (miRs), we examined genome-wide transcriptomics expression in the amygdala of rats prenatally exposed to VPA, and detected elevated miR-181c and miR-30d expression levels as well as dysregulated expression of their cognate mRNA targets encoding proteins involved in neuronal system development. Furthermore, selective suppression of miR-181c function attenuates neurite outgrowth and branching, and results in reduced synaptic density in primary amygdalar neurons in vitro. Collectively, these results implicate the small non-coding miR-181c in neuronal morphology, and provide a framework of understanding how dysregulation of a neurodevelopmentally relevant miR in the amygdala may contribute to the pathophysiology of ASD.


Assuntos
Tonsila do Cerebelo/metabolismo , Transtorno Autístico/genética , Transtorno Autístico/metabolismo , MicroRNAs/metabolismo , Tonsila do Cerebelo/patologia , Animais , Transtorno Autístico/induzido quimicamente , Transtorno Autístico/patologia , Modelos Animais de Doenças , Neurônios/metabolismo , Neurônios/patologia , Ratos , Comportamento Social , Transcriptoma , Ácido Valproico
3.
Cell Mol Life Sci ; 69(1): 89-102, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21833581

RESUMO

MicroRNAs (miRNAs) constitute a class of small, non-coding RNAs that act as post-transcriptional regulators of gene expression. In neurons, the functions of individual miRNAs are just beginning to emerge, and recent studies have elucidated roles for neural miRNAs at various stages of neuronal development and maturation, including neurite outgrowth, dendritogenesis, and spine formation. Notably, miRNAs regulate mRNA translation locally in the axosomal and synaptodendritic compartments, and thereby contribute to the dynamic spatial organization of axonal and dendritic structures and their function. Given the critical role for miRNAs in regulating early brain development and in mediating synaptic plasticity later in life, it is tempting to speculate that the pathology of neurological disorders is affected by altered expression or functioning of miRNAs. Here we provide an overview of recently identified mechanisms of neuronal development and plasticity involving miRNAs, and the consequences of miRNA dysregulation.


Assuntos
Encéfalo , MicroRNAs , Doenças do Sistema Nervoso , Neurogênese/fisiologia , Plasticidade Neuronal/genética , Animais , Encéfalo/crescimento & desenvolvimento , Encéfalo/metabolismo , Regulação da Expressão Gênica/fisiologia , Humanos , Camundongos , MicroRNAs/genética , MicroRNAs/metabolismo , Modelos Biológicos , Doenças do Sistema Nervoso/genética , Doenças do Sistema Nervoso/metabolismo , Neurônios/fisiologia , Biossíntese de Proteínas/fisiologia , Ratos
4.
Chemosphere ; 84(11): 1548-55, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21700314

RESUMO

Goczalkowice Reservoir is the biggest water reservoir in the south of Poland. For our studies bottom sediments were collected from eight different places of the reservoir at various seasons of the year. EPR spectroscopy was applied to analyse both quantitatively and qualitatively the humic acids (HA) present in the samples. EPR spectra of the extracted HA exhibited broad lines from the paramagnetic metal ions and narrow lines from free radicals. The values of the free radical concentration obtained for HA amounted to 1.14-13.6 × 1016 spin g(-1) depending on the season and the place of sample collection. The values of the g factor obtained for HA were of the range 2.0027-2.0035. The EPR studies show that HA extracted from bottom sediment collected at various points of the Goczalkowice Reservoir exhibit similar physical-chemical properties. It was also observed that the depth of the reservoir affects the content of the oxygen functional groups as well as the free radical concentration in HA. The identification of the functional groups was done by means of IR. UV/VIS spectroscopy was used to estimate the maturity of the HA.


Assuntos
Sedimentos Geológicos/análise , Substâncias Húmicas/análise , Poluentes do Solo/análise , Espectrofotometria Infravermelho , Espectrofotometria Ultravioleta , Espectroscopia de Ressonância de Spin Eletrônica , Radicais Livres/química
5.
Rev Sci Instrum ; 79(1): 013709, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18248041

RESUMO

We present the design and fabrication of a magnetoresistive imaging system capable of scanning 256 channels simultaneously along linear ranges of either 4 or 13 mm. High speed electronics read the channels and transfer the data to a computer that builds and displays the images. The system was successfully used to image magnetic tapes for real-time forensic validation purposes and can also be applied in other noninvasive imaging applications.


Assuntos
Aumento da Imagem/instrumentação , Interpretação de Imagem Assistida por Computador/instrumentação , Magnetismo/instrumentação , Processamento de Sinais Assistido por Computador , Transdutores , Gravação em Vídeo/instrumentação , Desenho de Equipamento , Análise de Falha de Equipamento , Aumento da Imagem/métodos , Interpretação de Imagem Assistida por Computador/métodos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Gravação em Vídeo/métodos
6.
Rev. bras. otorrinolaringol ; 70(1): 84-89, jan.-fev. 2004. tab
Artigo em Português | LILACS | ID: lil-359853

RESUMO

O potencial evocado auditivo de tronco encefálico (ABR) é um método simples, objetivo e não invasivo de avaliação das vias auditivas do tronco encefálico, que pode ser realizado em qualquer idade e que detecta a atividade elétrica desde a orelha interna até o colículo inferior. O ABR é composto por 7 ondas (I - VII), sendo as ondas I, III e V os componentes mais importantes. O nível de sensação (NS) é uma unidade de estímulo que se baseia no limiar psicoacústico do indivíduo e a esse limiar acrescenta-se uma determinada intensidade de estímulo em decibel (dB), com o objetivo de fornecer a mesma quantidade de energia acústica em caso de perdas auditivas assimétricas. OBJETIVO: Avaliar a influência da idade no ABR em homens, utilizando o NS como unidade de estímulo. FORMA DE ESTUDO: Observacional coorte com corte transversal. MATERIAL E MÉTODO: Quinze indivíduos do sexo masculino entre 20 e 30 anos e 15 do sexo masculino a partir de 60 anos passaram por um critério clínico de seleção a fim de afastar outros fatores que pudessem influenciar os resultados. Foram determinadas as latências absolutas das ondas I, III, e V e as latências interpicos (LIPs) I-III, III-V e I-V nos 2 grupos e os dados obtidos foram analisados estatisticamente. RESULTADOS: As latências absolutas e interpicos do ABR foram semelhantes nos 2 grupos estudados. CONCLUSÃO: No grupo etário analisado e nas condições pré-estabelecidas neste estudo, a idade não representou um fator de influência nos achados do ABR.

7.
@rq. otorrinolaringol ; 7(2): 129-141, jun. 2003. tab, graf
Artigo em Português | LILACS | ID: lil-417114

RESUMO

A rinossinusite bacteriana aguda é uma afecção de alta prevalência, na sua maioria originada de viroses das vias aéreas superiores. A terapia antimicrobiana com a claritromicina está bem estabelecida na literatura e corticoterapia sistêmica contribui como adjuvante no controle da inflamação, diminuindo o edema, facilitando a drenagem das secreções e a manutenção da permeabilidade dos óstios, favorecendo assim a cura clínica.


Assuntos
Humanos , Claritromicina , Prednisolona , Sinusite/prevenção & controle , Sinusite/terapia
8.
J Chem Inf Comput Sci ; 40(6): 1349-55, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11128093

RESUMO

The computer system PASS provides simultaneous prediction of several hundreds of biological activity types for any drug-like compound. The prediction is based on the analysis of structure-activity relationships of the training set including more than 30000 known biologically active compounds. In this paper we investigate the influence on the accuracy of predicting the types of activity with PASS by (a) reduction of the number of structures in the training set and (b) reduction of the number of known activities in the training set. The compounds from the MDDR database are used to create heterogeneous training and evaluation sets. We demonstrate that predictions are robust despite the exclusion of up to 60% of information.


Assuntos
Química Farmacêutica/métodos , Software , Bases de Dados Factuais , Avaliação Pré-Clínica de Medicamentos , Relação Estrutura-Atividade
10.
Psychol Rep ; 86(3 Pt 1): 858-62, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10876334

RESUMO

Cluster analysis techniques delineate groupings or categories of observations based on some shared commonality over a set of variables. If such groupings can be formed, their commonality may be investigated to define relationships that may otherwise go undetected given their complexity. However, the cluster analyses are inappropriate unless the results can be replicated. A number of clustering techniques are available, differing mostly in the technical criteria used to judge the similarity of the observations. There is added validity to the cluster structure when different methods produce similar groupings; however, in most cases, different clustering techniques will not produce identical clusters and the extent of cluster similarity becomes an important measure. In this paper the hypergeometric distribution is used to gauge cluster similarity across different methods, providing an appropriate measure of consistency. This measure is used to validate reproducibility of the clusters.


Assuntos
Análise por Conglomerados , Psicometria , Comparação Transcultural , Humanos , Determinação da Personalidade/estatística & dados numéricos , Reprodutibilidade dos Testes
11.
Pol Merkur Lekarski ; 4(22): 186-9, 1998 Apr.
Artigo em Polonês | MEDLINE | ID: mdl-9770992

RESUMO

Results of surgical procedures in malnutrished patients are worse than in well-nutrished patients. Perioperative nutritional treatment lead to diminished percentage of postoperative complications and mortality. Authors presents the influence of early postoperative enteral nutrition in 35 malnutrished patients on body composition and anthropometrical and biochemical parameters of their nutritional status. Results shows that enteral nutrition in postoperative phase can decrease catabolic effect of surgical treatment.


Assuntos
Nutrição Parenteral Total , Adulto , Índice de Massa Corporal , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Período Pós-Operatório , Estudos Retrospectivos
14.
Nature ; 323(6088): 558-60, 1986.
Artigo em Inglês | MEDLINE | ID: mdl-2429192

RESUMO

Hepatitis delta (delta) virus (HDV), a satellite virus of the hepatitis B virus (HBV), causes a severe form of viral hepatitis in humans. Here we present evidence based on electron microscopy and electrophoretic behaviour that HDV contains a single stranded circular RNA molecule. This is the first animal virus identified with a circular RNA genome. Circular RNAs have only been found in plant viruses. We have obtained a partial complementary DNA clone representing approximately 25% of the total genome of HDV. Analysis of this cDNA revealed similarity to two plant viruses that may explain the origin of the virus.


Assuntos
RNA Viral/genética , Sequência de Bases , Clonagem Molecular , DNA/genética , Vírus Delta da Hepatite/genética , Microscopia Eletrônica , RNA , RNA Circular , Homologia de Sequência do Ácido Nucleico
15.
Gene ; 39(2-3): 231-8, 1985.
Artigo em Inglês | MEDLINE | ID: mdl-2936650

RESUMO

The Aspergillus niger trpC gene was isolated by complementation experiments with an Escherichia coli trpC mutant. Plasmid DNA containing the A. niger trpC gene transforms an Aspergillus nidulans mutant strain, defective in all three enzymatic activities of the trpC gene, to Trp+, indicating the presence of a complete and functional trpC gene. Southern blot analysis of DNA from these Trp+ transformants showed that plasmid DNA was present but that this DNA was not integrated at the site of the chromosomal trpC locus. The A. niger trpC gene was localized on the cloned fragment by heterologous hybridization experiments and sequence analysis. These experiments suggest that the organization of the A. niger trpC gene is identical to that of the analogous A. nidulans trpC and the Neurospora crassa trp-1 genes.


Assuntos
Aldose-Cetose Isomerases , Antranilato Sintase , Aspergillus niger/genética , Genes Fúngicos , Transferases de Grupos Nitrogenados , Triptofano/genética , Sequência de Bases , Carboidratos Epimerases/genética , Mapeamento Cromossômico , Indol-3-Glicerolfosfato Sintase/genética , Neurospora crassa/genética , Hibridização de Ácido Nucleico , Seleção Genética , Homologia de Sequência do Ácido Nucleico , Transferases/genética
16.
Gene ; 15(4): 297-305, 1981 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-6277734

RESUMO

Vectors for cloning promoter-DNA fragments were derived from plasmid pBR313 (Bolivar et al., 1977). These have several unique restriction sites and carry the trpA gene from Escherichia coli as a selective marker. The selection is based on an enhancement of the growth rate of those bacteria in which the expression of trpA is directed by the cloned promoter. The expression of trpA can be determined quantitatively, independently of the copy number of the vector, and should reflect the apparent strength of the promoter, since the DNA segment located before trpA contains translational stop signals in all three reading frames.


Assuntos
Clonagem Molecular , Vetores Genéticos , Óperon , Plasmídeos , Triptofano/genética , Enzimas de Restrição do DNA/metabolismo , DNA Bacteriano , Escherichia coli/genética , Marcadores Genéticos , Especificidade por Substrato
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