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1.
Aquat Toxicol ; 221: 105445, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32078886

RESUMO

Despite the widespread use of nanoparticles (NPs), there are still major gaps of knowledge regarding the impact of nanomaterials in the environment and aquatic animals. The present work aimed to study the effects of 7 and 40 nm gold nanoparticles (AuNPs) - citrate and polyvinylpyrrolidone (PVP) coated - on the liver proteome of the estuarine/marine fish gilthead seabream (Sparus aurata). After 96 h, exposure to AuNP elicited alterations on the abundance of 26 proteins, when compared to the control group. AuNPs differentially affected several metabolic pathways in S. aurata liver cells. Among the affected proteins were those related to cytoskeleton and cell structure, gluconeogenesis, amino acids metabolism and several processes related to protein activity (protein synthesis, catabolism, folding and transport). The increased abundance of proteins associated with energy metabolism (ATP synthase subunit beta), stress response (94 kDa glucose-regulated protein) and cytoskeleton structure (actins and tubulins) may represent the first signs of cellular oxidative stress induced by AuNPs. Although higher gold accumulation was found in the liver of S. aurata exposed to 7 nm PVP-AuNPs, the 7 nm cAuNPs were more bioactive, inducing more effects in liver proteome. Gold accumulated more in the spleen than in the other assessed tissues of S. aurata exposed to AuNPs, highlighting its potential role on the elimination of these NPs.


Assuntos
Ouro/toxicidade , Fígado/efeitos dos fármacos , Nanopartículas Metálicas/toxicidade , Proteoma/metabolismo , Dourada/metabolismo , Poluentes Químicos da Água/toxicidade , Animais , Ácido Cítrico/química , Fígado/metabolismo , Redes e Vias Metabólicas/efeitos dos fármacos , Oxirredução , Estresse Oxidativo/efeitos dos fármacos , Povidona/química , Proteômica , Propriedades de Superfície
2.
Sci Total Environ ; 568: 1054-1058, 2016 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-27358197

RESUMO

Phytochelatins are metal-binding metabolites found in almost all plant species and some animal groups, including nematodes and annelids, where they can play an important role in detoxifying metals such as cadmium. Species from several other taxa contain a phytochelatin synthase (PCS) gene orthologue, including molluscs, indicating they may have the potential to synthesize phytochelatins. However, the presence of a gene alone does not demonstrate that it plays a functional role in metal detoxification. In the present study, we show that the aquatic snail Lymnaea stagnalis produced both penta- and heptapeptide phytochelatins (i.e. phytochelatin-2 and phytochelatin-3), and their levels increased in response to sub-lethal levels of cadmium.


Assuntos
Aminoaciltransferases/genética , Cádmio/toxicidade , Lymnaea/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Sequência de Aminoácidos , Aminoaciltransferases/química , Aminoaciltransferases/metabolismo , Animais , Lymnaea/metabolismo , Filogenia , Fitoquelatinas/biossíntese , Fitoquelatinas/metabolismo , Alinhamento de Sequência
3.
Rev. bras. pesqui. méd. biol ; Braz. j. med. biol. res;44(12): 1261-1268, Dec. 2011. ilus, tab
Artigo em Inglês | LILACS | ID: lil-606543

RESUMO

The objective of the present study was to evaluate the response of social anxiety disorder (SAD) patients to threat scenarios. First-choice responses to 12 scenarios describing conspecific threatening situations and mean scores of defensive direction and defensive intensity dimensions were compared between 87 SAD patients free of medication and 87 matched healthy controls (HC). A significant gender difference in the first-choice responses was identified for seven scenarios among HCs but only for two scenarios among SAD patients. A significantly higher proportion of SAD patients chose "freezing" in response to "Bush" and "Noise" scenarios, whereas the most frequent response by HCs to these scenarios was "check out". SAD males chose "run away" and "yell" more often than healthy men in response to the scenarios "Park" and "Elevator", respectively. There was a positive correlation between the severity of symptoms and both defensive direction and defensive intensity dimensions. Factorial analysis confirmed the gradient of defensive reactions derived from animal studies. SAD patients chose more urgent defensive responses to threat scenarios, seeming to perceive them as more dangerous than HCs and tending to move away from the source of threat. This is consistent with the hypothesis that the physiopathology of anxiety disorders involves brain structures responsible for defensive behaviors.


Assuntos
Adolescente , Adulto , Feminino , Humanos , Adulto Jovem , Transtornos de Ansiedade/psicologia , Mecanismos de Defesa , Medo/psicologia , Estudos de Casos e Controles , Modelos Psicológicos
4.
Neuroscience ; 156(3): 640-52, 2008 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-18760334

RESUMO

The developmental effects of thyroid hormones (TH) in mammalian brain are mainly mediated by nuclear receptors regulating gene expression. However, there are increasing evidences of nongenomic mechanisms of these hormones associated with kinase- and calcium-activated signaling pathways. In this context, the aim of the present work was to investigate the signaling pathways involved in the mechanism of action of TH on cytoskeletal phosphorylation in cerebral cortex of 15-day-old male rats. Results showed that L-thyroxine (L-T4) increased the intermediate filament (IF) phosphorylation independently of protein synthesis, without altering the total immunocontent of these proteins. Otherwise, neither 3,5,3'-triiodo-L-thyronine (L-T3) nor neurotransmitters (GABA, ATP, L-glutamate or epinephrine) acted on the IF-associated phosphorylation level. We also demonstrated that the mechanisms underlying the L-T4 effect on the cytoskeleton involve membrane initiated actions through Gi protein-coupled receptor. This evidence was reinforced by the inhibition of cyclic adenosine 5'-monophosphate (cAMP) levels. Moreover, we showed the participation of phospholipase C, protein kinase C, mitogen-activated protein kinase, calcium/calmodulin-dependent protein kinase II, intra- and extracellular Ca2+ mediating the effects of L-T4 on the cytoskeleton. Stimulation of 45Ca2+ uptake by L-T4 was also demonstrated. These findings demonstrate that L-T4 has important physiological roles modulating the cytoskeleton of neural cells during development.


Assuntos
Córtex Cerebral/efeitos dos fármacos , Filamentos Intermediários/metabolismo , Transdução de Sinais/efeitos dos fármacos , Tiroxina/farmacologia , Análise de Variância , Animais , Animais Recém-Nascidos , Autorradiografia/métodos , Cálcio/metabolismo , Quelantes/farmacologia , AMP Cíclico/metabolismo , Relação Dose-Resposta a Droga , Ácido Egtázico/análogos & derivados , Ácido Egtázico/farmacologia , Ativação Enzimática/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Proteína Glial Fibrilar Ácida/metabolismo , Técnicas In Vitro , Masculino , Toxina Pertussis/farmacologia , Fosforilação/efeitos dos fármacos , Ratos , Ratos Wistar , Fatores de Tempo , Vimentina/metabolismo
5.
Rev. bras. pesqui. méd. biol ; Braz. j. med. biol. res;41(4): 324-332, Apr. 2008. tab
Artigo em Inglês | LILACS | ID: lil-479680

RESUMO

A former study with scenarios conducted in Hawaii has suggested that humans share with non-human mammals the same basic defensive strategies - risk assessment, freezing, defensive threat, defensive attack, and flight. The selection of the most adaptive strategy is strongly influenced by features of the threat stimulus - magnitude, escapability, distance, ambiguity, and availability of a hiding place. Aiming at verifying if these strategies would be consistent in a different culture, 12 defensive scenarios were translated into Portuguese and adapted to the Brazilian culture. The sample consisted of male and female undergraduate students divided into two groups: 76 students, who evaluated the five dimensions of each scenario and 248 medical students, who chose the most likely response for each scenario. In agreement with the findings from studies of non-human mammal species, the scenarios were able to elicit different defensive behavioral responses, depending on features of the threat. "Flight" was chosen as the most likely response in scenarios evaluated as an unambiguous and intense threat, but with an available route of escape, whereas "attack" was chosen in an unambiguous, intense and close dangerous situation without an escape route. Less urgent behaviors, such as "check out", were chosen in scenarios evaluated as less intense, more distant and more ambiguous. Moreover, the results from the Brazilian sample were similar to the results obtained in the original study with Hawaiian students. These data suggest that a basic repertoire of defensive strategies is conserved along the mammalian evolution because they share similar functional benefits in maintaining fitness.


Assuntos
Adolescente , Adulto , Feminino , Humanos , Masculino , Ansiedade/psicologia , Evolução Biológica , Mecanismos de Defesa , Medo/psicologia , Estudantes/psicologia , Agressão , Análise de Variância , Brasil , Reação de Fuga/fisiologia , Havaí , Resposta de Imobilidade Tônica/fisiologia , Medição de Risco , Inquéritos e Questionários , Tradução , População Urbana
6.
Rev. bras. pesqui. méd. biol ; Braz. j. med. biol. res;38(9): 1429-1439, Sept. 2005. tab
Artigo em Inglês | LILACS | ID: lil-408374

RESUMO

The reliability and validity of a Portuguese version of the Young Mania Rating Scale were evaluated. The original scale was translated into and adapted to Portuguese by the authors. Definitions of clinical manifestations, a semi-structured anchored interview and more explicit rating criteria were added to the scale. Fifty-five adult subjects, aged 18 to 60 years, with a diagnosis of Current Manic Episode according to DSM-III-R criteria were assessed using the Young Mania Rating Scale as well as the Brief Psychiatric Rating Scale in two sessions held at intervals from 7 to 10 days. Good reliability ratings were obtained, with intra-class correlation coefficient of 0.97 for total scores, and levels of agreement above 0.80 (P < 0.001) for all individual items. Internal consistency analysis resulted in an alpha = 0.67 for the scale as a whole, and an alpha = 0.72 for each standardized item (P < 0.001). For the concurrent validity, a correlation of 0.78 was obtained by the Pearson coefficient between the total scores of the Young Mania Rating Scale and Brief Psychiatric Rating Scale. The results are similar to those reported for the English version, indicating that the Portuguese version of the scale constitutes a reliable and valid instrument for the assessment of manic patients.


Assuntos
Adolescente , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Transtorno Bipolar/diagnóstico , Inquéritos e Questionários , Escalas de Graduação Psiquiátrica , Reprodutibilidade dos Testes , Traduções
7.
Rev. bras. pesqui. méd. biol ; Braz. j. med. biol. res;35(10): 1209-1213, Oct. 2002. tab
Artigo em Inglês | LILACS | ID: lil-326241

RESUMO

The objective of the present study was to evaluate the factor structure of Bech's version of the Brief Psychiatric Rating Scale (BPRS), translated into Portuguese. The BPRS was administered to a heterogeneous group of psychiatric inpatients (N = 98) and outpatients (N = 62) in a University Hospital. Each patient was evaluated from one to eight times. The interval between consecutive interviews was one week for the inpatients and one month for the outpatients. The results were submitted to factorial analysis. The internal consistency of the total scale and of each factor was also estimated. Factorial analysis followed by normalized orthogonal rotation (Varimax) yielded four factors: Withdrawal-Retardation, Thinking Disorder, Anxious-Depression and Activation. Internal consistency measured by Cronbach's alpha coefficient ranged from 0.766 to 0.879. The data show that the factor structure of the present instrument is similar to that of the American version of the BPRS which contains 18 items, except for the absence of the fifth factor of the latter scale, Hostile-Suspiciousness


Assuntos
Humanos , Masculino , Feminino , Escalas de Graduação Psiquiátrica Breve , Transtornos Mentais , Brasil , Estudo de Avaliação , Análise Fatorial , Psicometria
9.
Rev. Inst. Med. Trop. Säo Paulo ; Rev. Inst. Med. Trop. Säo Paulo;26(4): 230-5, 1984.
Artigo em Inglês | LILACS | ID: lil-21335

RESUMO

Esta investigacao foi levada a efeito em 10 pequenas cidades do Estado da Bahia (Nordeste do Brasil), escolhidas atraves de um processo amostral. O objetivo foi estudar as correlacoes entre as prevalencias de hepatomegalia e esplenomegalia, em diferentes areas, com a prevalencia e a intensidade da infeccao pelo S. mansoni nas mesmas areas. Nossas conclusoes: sao: a) a morbidade esquistossomotica (prevalencias de hepatomegalia e esplenomegalia) foi diretamente correlacionada com a prevalencia e a intensidade da infeccao; b) a intensidade da infeccao (medida pelo numero de ovos nas fezes) mostrou ser um bom indicador do grau de morbidade, explicando a variacao da morbidade entre as areas melhor que a prevalencia da infeccao; c) a prevalencia de esplenomegalia e o tamanho medio do figado abaixo do rebordo costal na linha medio-esternal sao bom indicadores da prevalencia e da intensidade da infeccao pelo S. mansoni na comunidade. Nossas conclusoes trazem a possibilidade da construcao de equacoes de regressao definitivas entre indicadores de morbidade e indicadores de infeccao, de tal forma que o valor de um possa ser usado para predizer o valor do outro


Assuntos
Pré-Escolar , Criança , Adolescente , Humanos , Hepatomegalia , Esquistossomose , Esplenomegalia , Brasil
10.
Rev. Inst. Med. Trop. Säo Paulo ; Rev. Inst. Med. Trop. Säo Paulo;25(1): 22-4, 1983.
Artigo em Inglês | LILACS | ID: lil-13918

RESUMO

Analise de variancia foi aplicada em dados coletados sobre contagem de ovos de Schistosoma mansoni obtidos em aomstra de material fecal de 17 pacientes. O metodo utilizado foi o de filtracao e coloracao pela nihidrina (Metodo de Bell). Os resultados nao mostraram diferencas estatisticamente significantes entre individuos, embora entre estes houvessem portadores de diferentes formas clinicas da doenca. A analise dos componentes de variacao mostrou uma maior variacao entre amostras e a menor variacao foi verificada entre observadores. O erro entre as determinacoes foi considerado muito grande, influenciando deste modo o resultado dos outros componentes. Tendo em vista estes resultados deve-se ter cautela em classificar pacientes portadores de esquistossomose mansonica quanto ao grau de severidade, baseado em apenas uma contagem de ovos


Assuntos
Adulto , Humanos , Masculino , Feminino , Contagem de Ovos de Parasitas , Schistosoma mansoni , Esquistossomose
11.
RBM psiquiatr ; (5): 171-80, 1982.
Artigo em Português | LILACS | ID: lil-10016

RESUMO

O objetivo deste trabalho e descrever e analisar as diferencas entre servicos ambulatoriais de psiquiatria em uma mesma cidade. Dois servicos foram selecionados em uma cidade brasileira: Ribeirao Preto, Estado de Sao Paulo, sendo, respectivamente de um hospital psiquiatrico publico e de um hospital universitario


Assuntos
Adulto , Pessoa de Meia-Idade , Humanos , Masculino , Feminino , Assistência Ambulatorial , Hospitais Gerais , Hospitais Psiquiátricos , Transtornos Mentais
12.
Neurobiologia ; 45(4): 277-92, 1982.
Artigo em Português | LILACS | ID: lil-13208

RESUMO

Analisamos 15 criancas com o sindrome DCM, sendo 12 do sexo masculino, com idade media de 8 anos e 1 mes e 3 do sexo feminino, com idade media de 7 anos e 7 meses.Cada paciente foi submetido a entrevista estruturada, a historia contada pelos pais, e ainda avaliada do ponto de vista psiquiatrico, neurologico e psicometrico.Os resultados foram quantificados em forma de frequencia de ocorrencia e confrontados com os do grupo de criancas controle constituido de 13 sujeitos, sendo 8 do sexo masculino, com idade media de 7 anos. A comparacao entre os resultados dos dois grupos indicou as seguintes diferencas: a frequencia de ocorrencia dos sintomas e sinais e maior nas criancas DCM e que as diferencas da sintomatologia entre os dois grupos sao de ordem quantitativa. A analise dos nossos dados mostrou que o estudo interdisciplinar se mostrou efetivo para se diferenciar a crianca DCM da normal


Assuntos
Pré-Escolar , Criança , Humanos , Masculino , Feminino , Transtorno do Deficit de Atenção com Hiperatividade , Testes Psicológicos
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