Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 6 de 6
Filtrar
Mais filtros










Intervalo de ano de publicação
1.
Entropy (Basel) ; 23(6)2021 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-34071912

RESUMO

Despite that many image encryption systems based on chaotic or hyperchaotic systems have been proposed to protect different kinds of information, it has been crucial to achieve as much security as possible in such systems. In this sense, we numerically implement a known image encryption system with some variants, making special emphasis when two operations are considered in the scrambling stage. The variants of such an encryption system are based on some hyperchaotic systems, which generated some substitution boxes and the keys of the system. With the aim to have a more complete evaluation, some internal stages of the image encryption scheme have been evaluated by using common statistical tests, and also the scaling behavior of the encrypted images has been calculated by means of a two-dimensional detrended fluctuation analysis (2D-DFA). Our results show that the image encryption systems that include two operations or transformations in the scrambling stage present a better performance than those encryption systems that consider just one operation. In fact, the 2D-DFA approach was more sensitive than some common statistical tests to determine more clearly the impact of multiple operations in the scrambling process, confirming that this scaling method can be used as a perceptual security metric, and it may contribute to having better image encryption systems.

2.
Clin Exp Immunol ; 189(1): 47-59, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28263381

RESUMO

Clinical and epidemiological studies indicate that obesity affects the development and phenotype of asthma by inducing inflammatory mechanisms in addition to eosinophilic inflammation. The aim of this study was to assess the effect of obesity on allergic airway inflammation and T helper type 2 (Th2) immune responses using an experimental model of asthma in BALB/c mice. Mice fed a high-fat diet (HFD) for 10 weeks were sensitized and challenged with ovalbumin (OVA), and analyses were performed at 24 and 48 h after the last OVA challenge. Obesity induced an increase of inducible nitric oxide synthase (iNOS)-expressing macrophages and neutrophils which peaked at 48 h after the last OVA challenge, and was associated with higher levels of interleukin (IL)-4, IL-9, IL-17A, leptin and interferon (IFN)-γ in the lungs. Higher goblet cell hyperplasia was associated with elevated mast cell influx into the lungs and trachea in the obese allergic mice. In contrast, early eosinophil influx and lower levels of IL-25, thymic stromal lymphopoietin (TSLP), CCL11 and OVA-specific immunoglobulin (IgE) were observed in the obese allergic mice in comparison to non-obese allergic mice. Moreover, obese mice showed higher numbers of mast cells regardless of OVA challenge. These results indicate that obesity affects allergic airway inflammation through mechanisms involving mast cell influx and the release of TSLP and IL-25, which favoured a delayed immune response with an exacerbated Th1, Th2 and Th17 profile. In this scenario, an intense mixed inflammatory granulocyte influx, classically activated macrophage accumulation and intense mucus production may contribute to a refractory therapeutic response and exacerbate asthma severity.


Assuntos
Asma/imunologia , Eosinófilos/imunologia , Obesidade/fisiopatologia , Linfócitos T Auxiliares-Indutores/imunologia , Animais , Líquido da Lavagem Broncoalveolar , Citocinas/imunologia , Citocinas/metabolismo , Modelos Animais de Doenças , Feminino , Imunoglobulina E/imunologia , Inflamação/imunologia , Contagem de Leucócitos , Pulmão/patologia , Macrófagos/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Neutrófilos/imunologia , Óxido Nítrico Sintase Tipo II/metabolismo , Ovalbumina , Linfopoietina do Estroma do Timo
3.
Braz J Med Biol Res ; 32(11): 1429-36, 1999 11.
Artigo em Inglês | MEDLINE | ID: mdl-10559845

RESUMO

Injection of an Ascaris suum extract (Asc) affects both the humoral and cellular immune responses to unrelated antigens when it is co-administered with these antigens. In the present study we evaluated the effect of Asc on macrophage activation in the early phase of Mycobacterium bovis BCG (Pasteur strain TMCC 1173) infection in C57Bl/6 mice. C57Bl/6 mice were injected intraperitoneally (ip) with 0.1 mg BCG (BCG group) or BCG plus 1 mg Asc (BCG + Asc group). The peritoneal exudates were obtained at 2, 7 and 14 days after infection. The numbers of IFN-gamma-secreting cells were assessed by the ELISPOT assay. Nitric oxide (NO) production was measured by the Griess method and by the evaluation of NADPH diaphorase activity in the peritoneal exudates. The administration of Asc extract increased NADPH diaphorase activity (2 days: control = 0, BCG = 7%, BCG + Asc = 13%, and Asc = 4%; 7 days: control = 4, BCG = 13%, BCG + Asc = 21%, and Asc = 4.5%) and TNF-alpha levels (mean +/- SD; 2 days: control = 0, BCG = 169 +/- 13, BCG + Asc = 202 +/- 37, and Asc = 0; 7 days: control = 0, BCG = 545 +/- 15.5, BCG + Asc = 2206 +/- 160.6, and Asc = 126 +/- 26; 14 days: control = 10 +/- 1.45, BCG = 9 +/- 1.15, BCG + Asc = 126 +/- 18, and Asc = 880 +/- 47.67 pg/ml) in the early phase of BCG infection. Low levels of NO production were detected at 2 and 7 days after BCG infection, increasing at 14 days (mean +/- SD; 2 days: control = 0, BCG = 3.7 +/- 1.59, BCG + Asc = 0.82 +/- 0.005, Asc = 0.48 +/- 0.33; 7 days: control = 0, BCG = 2.78 +/- 1.54, BCG + Asc = 3.07 +/- 1.05, Asc = 0; 14 days: control = 0, BCG = 9.05 +/- 0.53, BCG + Asc = 9.61 +/- 0.81, Asc = 10.5 +/- 0.2 (2 x 10(6)) cells/ml). Furthermore, we also observed that Asc co-injection induced a decrease of BCG-colony-forming units (CFU) in the spleens of BCG-infected mice during the first week of infection (mean +/- SD; 2 days: BCG = 1.13 +/- 0.07 and BCG + Asc = 0.798 +/- 0.305; 7 days: BCG = 1.375 +/- 0. 194 and BCG + Asc = 0.548 +/- 0.0226; 14 days: BCG = 0.473 +/- 0.184 and BCG + Asc = 0.675 +/- 0.065 (x 10(2)) CFU). The present data suggest that Asc induces the enhancement of the immune response in the early phase of BCG infection.


Assuntos
Antígenos de Helmintos/farmacologia , Ascaris suum/imunologia , Ativação de Macrófagos/efeitos dos fármacos , Mycobacterium bovis/efeitos dos fármacos , Óxido Nítrico/metabolismo , Baço/microbiologia , Tuberculose/imunologia , Animais , Contagem de Colônia Microbiana , Feminino , Interferon gama/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , NADPH Desidrogenase/metabolismo , Fatores de Tempo , Fator de Necrose Tumoral alfa/biossíntese
4.
Braz. j. med. biol. res ; 32(11): 1429-36, Nov. 1999. graf, tab
Artigo em Inglês | LILACS | ID: lil-248437

RESUMO

Injection of an Ascaris suum extract (Asc) affects both the humoral and cellular immune responses to unrelated antigens when it is co-administered with these antigens. In the present study we evaluated the effect of Asc on macrophage activation in the early phase of Mycobacterium bovis BCG (Pasteur strain TMCC 1173) infection in C57Bl/6 mice. C57Bl/6 mice were injected intraperitoneally (ip) with 0.1 mg BCG (BCG group) or BCG plus 1 mg Asc (BCG + Asc group). The peritoneal exudates were obtained at 2, 7 and 14 days after infection. The numbers of IFN-g-secreting cells were assessed by the ELISPOT assay. Nitric oxide (NO) production was measured by the Griess method and by the evaluation of NADPH diaphorase activity in the peritoneal exudates. The administration of Asc extract increased NADPH diaphorase activity (2 days: control = 0, BCG = 7 per cent, BCG + Asc = 13 per cent, and Asc = 4 per cent; 7 days: control = 4, BCG = 13 per cent, BCG + Asc = 21 per cent, and Asc = 4.5 per cent) and TNF-a levels (mean + or - SD; 2 days: control = 0, BCG = 169 + or - 13, BCG + Asc = 202 + or - 37, and Asc = 0; 7 days: control = 0, BCG = 545 + or - 15.5, BCG + Asc = 2206 + or - 160.6, and Asc = 126 + or - 26; 14 days: control = 10 + or - 1.45, BCG = 9 + or - 1.15, BCG + Asc = 126 + or - 18, and Asc = 880 + or - 47.67 pg/ml) in the early phase of BCG infection. Low levels of NO production were detected at 2 and 7 days after BCG infection, increasing at 14 days (mean + or - SD; 2 days: control = 0, BCG = 3.7 + or - 1.59, BCG + Asc = 0.82 + or - 0.005, Asc = 0.48 + or - 0.33; 7 days: control = 0, BCG = 2.78 + or - 1.54, BCG + Asc = 3.07 + or - 1.05, Asc = 0; 14 days: control = 0, BCG = 9.05 + or - 0.53, BCG + Asc = 9.61 + or - 0.81, Asc = 10.5 + or - 0.2 (2 x 106) cells/ml). Furthermore, we also observed that Asc co-injection induced a decrease of BCG-colony-forming units (CFU) in the spleens of BCG-infected mice during the first week of infection (mean + or - SD; 2 days: BCG = 1.13 + or - 0.07 and BCG + Asc = 0.798 + or - 0.305; 7 days: BCG = 1.375 + or - 0.194 and BCG + Asc = 0.548 + or - 0.0226; 14 days: BCG = 0.473 + or - 0.184 and BCG + Asc = 0.675 + or - 0.065 (x 102) CFU). The present data suggest that Asc induces the enhancement of the immune response in the early phase of BCG infection.


Assuntos
Animais , Feminino , Camundongos , Antígenos de Helmintos/farmacologia , Ascaris suum/imunologia , Ativação de Macrófagos/efeitos dos fármacos , Mycobacterium bovis/efeitos dos fármacos , Baço/microbiologia , Células-Tronco/efeitos dos fármacos , Tuberculose/veterinária , NADPH Desidrogenase/metabolismo , Fatores de Tempo , Fator de Necrose Tumoral alfa/biossíntese
5.
Acta Psiquiatr Psicol Am Lat ; 33(2): 131-41, 1987 Jun.
Artigo em Espanhol | MEDLINE | ID: mdl-3425356

RESUMO

A description of rehabilitation work at a psychiatric ward with all the benefits specific modalities, and results involved is offered. Focusing from a multidisciplinary angle the authors aim at laying the foundations for the setting up of rehabilitation workteams, in the frame of psychiatric hospitals in our country. At the same time clinical examples are submitted to illustrate situations which had to be met during the work and their linking to setting and transference as well.


Assuntos
Equipe de Assistência ao Paciente , Unidade Hospitalar de Psiquiatria , Psicoterapia , Transtornos Psicóticos/reabilitação , Adulto , Arteterapia , Humanos , Masculino , Pessoa de Meia-Idade , Ludoterapia , Identificação Social , Transferência de Experiência
6.
Acta Psiquiatr. Psicol. Am. Lat ; 33(2): 131-41, 1987 Jun.
Artigo em Espanhol | BINACIS | ID: bin-52691

RESUMO

A description of rehabilitation work at a psychiatric ward with all the benefits specific modalities, and results involved is offered. Focusing from a multidisciplinary angle the authors aim at laying the foundations for the setting up of rehabilitation workteams, in the frame of psychiatric hospitals in our country. At the same time clinical examples are submitted to illustrate situations which had to be met during the work and their linking to setting and transference as well.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...