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1.
Histochem Cell Biol ; 161(5): 409-421, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38402366

RESUMO

Cancer is understood as a multifactorial disease that involve multiple cell types and phenotypes in the tumor microenvironment (TME). The components of the TME can interact directly or via soluble factors (cytokines, chemokines, growth factors, extracellular vesicles, etc.). Among the cells composing the TME, mesenchymal stem cells (MSCs) appear as a population with debated properties since it has been seen that they can both promote or attenuate tumor progression. For various authors, the main mechanism of interaction of MSCs is through their secretome, the set of molecules secreted into the extracellular milieu, recruiting, and influencing the behavior of other cells in inflammatory environments where they normally reside, such as wounds and tumors. Natural products have been studied as possible cancer treatments, appealing to synergisms between the molecules in their composition; thus, extracts obtained from Petiveria alliacea (Anamu-SC) and Caesalpinia spinosa (P2Et) have been produced and studied previously on different models, showing promising results. The effect of plant extracts on the MSC secretome has been poorly studied, especially in the context of the TME. Here, we studied the effect of Anamu-SC and P2Et extracts in the human adipose-derived MSC (hAMSC)-tumor cell interaction as a TME model. We also investigated the influence of the hAMSC secretome, in combination with these natural products, on tumor cell hallmarks such as viability, clonogenicity, and migration. In addition, hAMSC gene expression and protein synthesis were evaluated for some key factors in tumor progression in the presence of the extracts by reverse transcription-quantitative polymerase chain reaction (RT-qPCR) and Multiplex, respectively. It was found that the presence of the hAMSC secretome did not affect the cytotoxic or clonogenicity-reducing activities of the natural extracts on cancer cells, and even this secretome can inhibit the migration of these tumor cells, in addition to the fact that the profile of molecules can be modified by natural products. Overall, our findings demonstrate that hAMSC secretome participation in TME interactions can favor the antitumor activities of natural products.


Assuntos
Células-Tronco Mesenquimais , Extratos Vegetais , Secretoma , Humanos , Células-Tronco Mesenquimais/metabolismo , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Secretoma/metabolismo , Antineoplásicos Fitogênicos/farmacologia , Antineoplásicos Fitogênicos/química , Células Cultivadas , Proliferação de Células/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais
2.
Cell Death Dis ; 7(6): e2243, 2016 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-27253407

RESUMO

Recent findings suggest that part of the anti-tumor effects of several chemotherapeutic agents require an intact immune system. This is in part due to the induction of immunogenic cell death. We have identified a gallotannin-rich fraction, obtained from Caesalpinia spinosa (P2Et) as an anti-tumor agent in both breast carcinoma and melanoma. Here, we report that P2Et treatment results in activation of caspase 3 and 9, mobilization of cytochrome c and externalization of annexin V in tumor cells, thus suggesting the induction of apoptosis. This was preceded by the onset of autophagy and the expression of immunogenic cell death markers. We further demonstrate that P2Et-treated tumor cells are highly immunogenic in vaccinated mice and induce immune system activation, clearly shown by the generation of interferon gamma (IFN-γ) producing tyrosine-related protein 2 antigen-specific CD8+ T cells. Moreover, the tumor protective effects of P2Et treatment were abolished in immunodeficient mice, and partially lost after CD4 and CD8 depletion, indicating that P2Et's anti-tumor activity is highly dependent on immune system and at least in part of T cells. Altogether, these results support the hypothesis that the gallotannin-rich fraction P2Et's anti-tumor effects are mediated to a great extent by the endogenous immune response following to the exposure to immunogenic dying tumor cells.


Assuntos
Antineoplásicos/uso terapêutico , Sistema Imunitário/efeitos dos fármacos , Melanoma Experimental/tratamento farmacológico , Extratos Vegetais/uso terapêutico , Polifenóis/uso terapêutico , Animais , Antígenos de Neoplasias/imunologia , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Biomarcadores/metabolismo , Calreticulina/metabolismo , Caspase 3/metabolismo , Caspase 9/metabolismo , Proliferação de Células/efeitos dos fármacos , Células Dendríticas/efeitos dos fármacos , Células Dendríticas/metabolismo , Modelos Animais de Doenças , Doxorrubicina/farmacologia , Ativação Enzimática/efeitos dos fármacos , Humanos , Melanoma Experimental/patologia , Camundongos , Camundongos Endogâmicos C57BL , Fitoterapia , Extratos Vegetais/farmacologia , Polifenóis/farmacologia , Linfócitos T/efeitos dos fármacos , Linfócitos T/imunologia , Vacinação
3.
Arq. bras. med. vet. zootec ; 65(5): 1447-1453, out. 2013. graf, tab
Artigo em Português | LILACS | ID: lil-689764

RESUMO

Objetivou-se com este trabalho avaliar a taxa de lotação e a produção de leite de vacas mestiças Holandês x Zebu em pastagens de Tifton 85 irrigadas e em sequeiro, em Uberaba-MG. Os dados foram analisados em um delineamento de blocos inteiramente ao acaso, com três repetições por tratamento, num esquema fatorial 2x10 (dois tratamentos e 10 épocas). Foi utilizado um lote de 11 vacas em lactação por tratamento para avaliação do desempenho animal. As médias foram comparadas por meio do teste de Scott-Knott ao nível de 5% de probabilidade (P<0,05). A pastagem foi manejada em sistema de pastejo rotacionado com três e cinco dias de ocupação e 21 e 35 dias de descanso no período das águas e da seca, respectivamente. A taxa de lotação média do sistema irrigado, no período avaliado, foi de 4,6 UA.ha-1, valor superior (P<0,05) à taxa média de 2,2 UA.ha-1 observada para o sistema de sequeiro. Não houve diferenças nas produções diárias de leite das vacas (P<0,05). A produção de leite média obtida no sistema irrigado foi de 51,7 litros. ha-1.dia-1. A irrigação possibilitou uma considerável intensificação do sistema, na medida em que proporcionou uma taxa de lotação bastante superior ao sistema de sequeiro.


The aim of this study was to determine the stocking rates and milk production of crossbred Holstein x Zebu cows managed under irrigated or rainfed Tifton 85 pastures in Uberaba- MG. The statistical design adopted was completely randomized blocks with three repetitions per treatment, in a 2 x 10 factorial arrangement (2 treatments and 10 seasons). The average was compared using the Scott-Knott test with 5% probability (P<0.05). To evaluate animal performance, 11 lactating cows per treatment were used. The pasture was managed in a rotational grazing system with 21 and 35 days of grazing interval and 3 and 5 days of grazing in each paddock, in the rainy and dry seasons respectively. The stocking rate of the irrigated system was 4.6 UA.ha-1 and was superior (p<0.05) to the stocking rate of the rainfed system that was 2.2 UA.ha-1. There were no differences among the systems (p>0.05) for the average daily milk yield of the cows. In the irrigated system the average milk yield was 51.7 liters.ha-1.dia-1. With irrigation, a considerable intensification of the system was possible because it provided a superior stocking rate capacity compared to the rainfed system.


Assuntos
Animais , Bovinos , Bovinos/anatomia & histologia , Bovinos/fisiologia , Cynodon/crescimento & desenvolvimento , Pastagens/análise , Pastagens/métodos , Animais , Leite/fisiologia , Leite
4.
J Rehabil Res Dev ; 37(1): 53-63, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10847572

RESUMO

In line with the mission of the Assistive Technology Act of 1998 (ATA), this study proposes an integrated assistive real-time system which "affirms that technology is a valuable tool that can be used to improve the lives of people with disabilities." An assistive technology device is defined by the ATA as "any item, piece of equipment, or product system, whether acquired commercially, modified, or customized, that is used to increase, maintain, or improve the functional capabilities of individuals with disabilities." The purpose of this study is to design and develop an alternate input device that can be used even by individuals with severe motor disabilities. This real-time system design utilizes electromyographic (EMG) biosignals from cranial muscles and electroencephalographic (EEG) biosignals from the cerebrum's occipital lobe, which are transformed into controls for two-dimensional (2-D) cursor movement, the left-click (Enter) command, and an ON/OFF switch for the cursor-control functions. This HCI system classifies biosignals into "mouse" functions by applying amplitude thresholds and performing power spectral density (PSD) estimations on discrete windows of data. Spectral power summations are aggregated over several frequency bands between 8 and 500 Hz and then compared to produce the correct classification. The result is an affordable DSP-based system that, when combined with an on-screen keyboard, enables the user to fully operate a computer without using any extremities.


Assuntos
Eletroencefalografia/instrumentação , Eletromiografia/instrumentação , Transtornos das Habilidades Motoras/reabilitação , Tecnologia Assistiva , Interface Usuário-Computador , Biorretroalimentação Psicológica , Desenho de Equipamento , Estudos de Avaliação como Assunto , Feminino , Humanos , Escala de Gravidade do Ferimento , Masculino , Sensibilidade e Especificidade , Processamento de Sinais Assistido por Computador/instrumentação
5.
Med Trop (Mars) ; 51(4): 421-7, 1991.
Artigo em Francês | MEDLINE | ID: mdl-1800881

RESUMO

The Bresilian civilization presents a mixing of cultures (african, european, amerindian ... ) who are original but complicated in a socio-economical context of a developing country. Psychiater and anthropologist, the author tries to inquire into the secret of traditional practitioners. He thinks that they play a prominent part in the individual medicine near the official medicine and they will be precious assistants in the Bresilian Health System after a complementary formation in the Hospital.


Assuntos
Medicina Tradicional , Atitude Frente a Saúde/etnologia , Brasil , Características Culturais , Países em Desenvolvimento , Humanos , Relações Interpessoais , Relações Interprofissionais , Tocologia , Fitoterapia , Religião e Medicina
6.
Arq Bras Cardiol ; 56(3): 235-7, 1991 Mar.
Artigo em Português | MEDLINE | ID: mdl-1832277

RESUMO

A man with chronic alcoholism presenting with recent-onset congestive heart failure and hyperdynamic features. Low arteriovenous oxygen content difference suggested high cardiac output. After 10 days of alcohol withdrawal, rest and balanced feeding the patient was asymptomatic and cardiomegaly subsided. No supplementation of thiamine was required.


Assuntos
Alcoolismo/complicações , Beriberi/complicações , Insuficiência Cardíaca/etiologia , Adulto , Cardiomegalia/etiologia , Insuficiência Cardíaca/diagnóstico por imagem , Humanos , Masculino , Radiografia
8.
Rev. microbiol ; 13(2): 187-91, 1982.
Artigo em Português | LILACS | ID: lil-9914

RESUMO

A partir de amostras de solo poluido com residuos domesticos e petroleo, de solo de jardim e de esgoto, foram isoladas 130 estirpes de micobacteria, atraves do tratamento previo com solucao de hidroxido de sodio a 4% e de verde malaquita a 0,2%.Cerca de 70% dos microrganismos isolados foram identificados como potencialmente patogenicos e representados na sua maioria por M. fortuitum (62%) e M. scrofulaceum (7%). Avaliando-se a capacidade da degradacao de petroleo, diesel, heptadecano e hexadecano, apenas as estirpes de M. fortuitum apresentaram crescimento nos dois primeiros substratos em 28 dias de incubacao. Em relacao aos hidrocarbonetos, estes mesmos microrganismos cresceram em 14 dias. As estirpes de M. diernhoferi, M. phlei, M. scrofulaceum e M. flavescens somente cresceram no heptadecano apos 28 dias. As micobacterias, isoladas de ambiente poluido com residuos de oleo, nao demonstraram atividade mais intensa na presenca destes substratos, demonstrando que esta propriedade nao depende da procedencia dos microrganismos


Assuntos
Microbiologia do Solo , Mycobacterium , Águas Residuárias , Hidrocarbonetos , Petróleo
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