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2.
Braz. j. med. biol. res ; 47(8): 655-661, 08/2014. tab, graf
Artigo em Inglês | LILACS | ID: lil-716268

RESUMO

Immune response plays an important role in the development of hepatic fibrosis. In the present study, we investigated the effects of quercetin on hepatitis and hepatic fibrosis induced by immunological mechanism. In the acute hepatitis model, quercetin (2.5 mg/kg) was injected iv into mice 30 min after concanavalin A (Con A) challenge. Mice were sacrificed 4 or 24 h after Con A injection, and aminotransferase tests and histopathological sections were performed. Treatment with quercetin significantly decreased the levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST). Consistent with this observation, treatment with quercetin markedly attenuated the pathologic changes in the liver. A hepatic fibrosis model was also generated in mice by Con A challenge once a week for 6 consecutive weeks. Mice in the experimental group were treated with daily iv injections of quercetin (0.5 mg/kg). Histopathological analyses revealed that treatment with quercetin markedly decreased collagen deposition, pseudolobuli development, and hepatic stellate cells activation. We also examined the effects of quercetin on the nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) and transforming growth factor beta (TGF-β) pathways by immunohistochemistry and real-time reverse transcriptase-polymerase chain reaction (RT-PCR). NF-κB and TGF-β production was decreased after treatment with quercetin, indicating that the antifibrotic effect of quercetin is associated with its ability to modulate NF-κB and TGF-β production. These results suggest that quercetin may be an effective therapeutic strategy in the treatment of patients with liver damage and fibrosis.


Assuntos
Animais , Feminino , Antioxidantes/administração & dosagem , Hepatite/tratamento farmacológico , Cirrose Hepática/tratamento farmacológico , Quercetina/farmacologia , Alanina Transaminase/sangue , Aspartato Aminotransferases/sangue , Concanavalina A , Colágeno/análise , Modelos Animais de Doenças , Células Estreladas do Fígado/efeitos dos fármacos , Células Estreladas do Fígado/metabolismo , Lipossomos , Cirrose Hepática/induzido quimicamente , Camundongos Endogâmicos BALB C , Mitógenos , NF-kappa B/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fator de Crescimento Transformador beta/metabolismo
3.
Braz. j. med. biol. res ; 46(3): 245-252, 15/mar. 2013. tab, graf
Artigo em Inglês | LILACS | ID: lil-670899

RESUMO

The objective this study was to determine the effect of phytohemagglutinin (PHA) on survival, growth and gene expression in caprine secondary follicles cultured in vitro. Secondary follicles (∼0.2 mm) were isolated from the cortex of caprine ovaries and cultured individually for 6 days in α-MEM+ supplemented with PHA (0, 1, 10, 50, 100, or 200 µg/mL). After 6 days of culture, follicle diameter and survival, antrum formation, ultrastructure and expression of mRNA for FSH receptors (FSH-R), proliferating cell nuclear antigen (PCNA), and neuronal nitric oxide synthase were determined. All treatments maintained follicular survival [α-MEM+ (94.59%); 1 µg/mL PHA (96.43%); 10 µg/mL PHA (84.85%); 50 µg/mL PHA (85.29%); 100 µg/mL PHA (88.57%), and 200 µg/mL PHA (87.50)], but the presence of 10 µg/mL PHA in the culture medium increased the antrum formation rate (21.21%) when compared with control (5.41%, P < 0.05) and ensured the maintenance of oocyte and granulosa cell ultrastructures after 6 days of culture. The expression of mRNA for FSH-R (2.7 ± 0.1) and PCNA (4.4 ± 0.2) was also significantly increased in follicles cultured with 10 µg/mL PHA in relation to those cultured in α-MEM+ (1.0 ± 0.1). In conclusion, supplementation of culture medium with 10 µg/mL PHA maintains the follicular viability and ultrastructure, and promotes the formation of antral cavity after 6 days of culture in vitro.


Assuntos
Animais , Feminino , Hormônio Foliculoestimulante/metabolismo , Mitógenos/farmacologia , Folículo Ovariano/efeitos dos fármacos , Fito-Hemaglutininas/farmacologia , Hormônio Foliculoestimulante/genética , Cabras , Técnicas In Vitro , Folículo Ovariano/crescimento & desenvolvimento , Folículo Ovariano/ultraestrutura , Antígeno Nuclear de Célula em Proliferação/metabolismo , RNA Mensageiro/metabolismo
4.
Clinics ; 67(6): 587-590, 2012. tab
Artigo em Inglês | LILACS | ID: lil-640207

RESUMO

OBJECTIVE: This study aims to evaluate the production of interferon-gamma and interleukin-10 by stimulated peripheral blood mononuclear cells isolated from patients with supraglottic laryngeal cancer before and after surgical treatment. METHODS: Fourteen patients with advanced supraglottic laryngeal cancer were studied. Cultures of peripheral blood mononuclear cells isolated during the preoperative and late postoperative periods were stimulated with concanavalin A and Bacille Calmette-Guerin, and the supernatant concentrations of interferon-gamma and interleukin-10 were measured. RESULTS: For non-stimulated cultures, the interferon-gamma levels produced by the preoperative period and the late postoperative period cultures were lower than the levels produced by the control group cultures. The interferon-gamma levels after stimulation with concanavalin A were higher in the late postoperative period cultures than in the preoperative evaluation cultures. Stimulation with Bacille Calmette-Guerin led to the production of similar levels of interferon-gamma and interleukin-10 by all cultures; thus, stimulation increased the levels of interferon-gamma produced by both the preoperative and postoperative cultures relative to the levels produced by the corresponding unstimulated cultures. CONCLUSION: Patients with advanced supraglottic laryngeal cancer exhibit an in vitro deficiency in interferongamma secretion by mononuclear cells. Stimulated cells seem to recover this function during the postoperative period.


Assuntos
Adolescente , Adulto , Criança , Feminino , Humanos , Masculino , Adulto Jovem , Carcinoma/sangue , Interferon gama/biossíntese , /biossíntese , Neoplasias Laríngeas/sangue , Leucócitos Mononucleares/metabolismo , Estudos de Casos e Controles , Carcinoma/patologia , Concanavalina A/farmacologia , Citocinas/sangue , Interferon gama/sangue , /sangue , Neoplasias Laríngeas/patologia , Leucócitos Mononucleares/efeitos dos fármacos , Mycobacterium bovis , Mitógenos/farmacologia , Estadiamento de Neoplasias , Estatísticas não Paramétricas
5.
Braz. j. med. biol. res ; 44(12): 1231-1242, Dec. 2011. ilus, tab
Artigo em Inglês | LILACS | ID: lil-606547

RESUMO

The mitogenic effects of periodic mechanical stress on chondrocytes have been studied extensively but the mechanisms whereby chondrocytes sense and respond to periodic mechanical stress remain a matter of debate. We explored the signal transduction pathways of chondrocyte proliferation and matrix synthesis under periodic mechanical stress. In particular, we sought to identify the role of the MEK1/2-ERK1/2 signaling pathway in chondrocyte proliferation and matrix synthesis following cyclic physiologic mechanical compression. Under periodic mechanical stress, both rat chondrocyte proliferation and matrix synthesis were significantly increased (P < 0.05) and were associated with increases in the phosphorylation of Src, PLCγ1, MEK1/2, and ERK1/2 (P < 0.05). Pretreatment with the MEK1/2-ERK1/2 selective inhibitor, PD98059, and shRNA targeted to ERK1/2 reduced periodic mechanical stress-induced chondrocyte proliferation and matrix synthesis (P < 0.05), while the phosphorylation levels of Src-Tyr418 and PLCγ1-Tyr783 were not inhibited. Proliferation, matrix synthesis and phosphorylation of MEK1/2-Ser217/221 and ERK1/2-Thr202/Tyr204 were inhibited after pretreatment with the PLCγ1 inhibitor U73122 in chondrocytes in response to periodic mechanical stress (P < 0.05), while the phosphorylation site of Src-Tyr418 was not affected. Inhibition of Src activity with PP2 and shRNA targeted to Src abrogated chondrocyte proliferation and matrix synthesis (P < 0.05) and attenuated PLCγ1, MEK1/2 and ERK1/2 activation in chondrocytes subjected to periodic mechanical stress (P < 0.05). These findings suggest that periodic mechanical stress promotes chondrocyte proliferation and matrix synthesis in part through the Src-PLCγ1-MEK1/2-ERK1/2 signaling pathway, which links these three important signaling molecules into a mitogenic cascade.


Assuntos
Animais , Ratos , Condrócitos/citologia , Condrócitos/enzimologia , Sistema de Sinalização das MAP Quinases/fisiologia , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Estresse Mecânico , Sistema de Sinalização das MAP Quinases/genética , Proteína Quinase 1 Ativada por Mitógeno/genética , Quinases de Proteína Quinase Ativadas por Mitógeno/genética , Mitógenos/metabolismo , Fosfolipase C gama/metabolismo , Ratos Sprague-Dawley , Quinases da Família src/metabolismo
6.
Biomédica (Bogotá) ; 30(4): 551-558, dic. 2010. ilus
Artigo em Espanhol | LILACS | ID: lil-616850

RESUMO

Introducción. Varios estudios in vitro sugieren que la proliferación, migración y supervivencia en líneas celulares de cáncer de seno se ven significativamente afectadas por la activación del receptor IGF de tipo I (Insulin-like Growth Factor-I Receptor, IGF-IR).Objetivo. Caracterizar la fosforilación del IGF-IR y las moléculas de señalización intracelular Akt y Erk1/2 (vías de señalización PI-3K y MAPK, respectivamente), causada por el factor IGF-I en una línea celular colombiana de cáncer de mama ductal infiltrante (CSC 1595). Materiales y métodos. Las líneas celulares CSC 1595 y MCF-7 se cultivaron en medio DMEM con suplemento de suero fetal bovino 10%, glutamina 2 mM, penicilina 100 U/ml, estreptomicina 100 µg/ml a 37 0C, atmósfera de CO2 al 5% y humedad de 95%. Los extractos celulares se sometieron a inmunoprecipitación e inmunodetección con anticuerpos específicos anti-pIGF-IR, anti-pERK1/2 y anti-pAkt. Resultados. Cinco minutos después del estímulo con 10 nM de IGF-I, 70% y 25% del IGF-IR fueron fosforilados en las células CSC 1595 y MCF-7, respectivamente; también se observó activación de las proteínas Akt y ERK1/2. Los niveles basales y estimulados de las proteínas ERK1/2 fueron significativamente más altos en las células CSC 1595, comparados a los observados en MCF-7. Conclusiones. El IGF-IR y la vía MAPK cinasa que involucra las proteínas ERK1/2 muestran una fosforilación mayor en las células 1595 a la observada en las MCF-7. El IGF-IR, principal activador de esta vía, podría jugar un papel importante en los procesos de proliferación y metástasis de tumores de cáncer de mama ductal infiltrante.


Introduction. In vitro studies strongly suggest that proliferation, migration and cell survival of breast cancer cell lines are significantly affected by activation of the IGF type 1 receptor (IGF-IR).Objective. The phosphorylation by IGF-I of IGF-IR and the intracellular signaling molecules Akt (PI-3K pathway) and Erk1/2 (MAPK pathway) was characterized in a human breast cancer cell lines. Materials and methods. The study compared a standard breast adenocarcinoma line (MCF-7) cell line with a line (CSC 1595) derived from an infiltrating ductal breast cancer in a Colombian patient. The CSC 1595 and MCF-7 cell lines were cultured in DMEM supplemented with 10% fetal bovine serum, 2 mM glutamine, 100 U/ml penicillin, and 100 µg/ml streptomycin and grown at 37°C in 5% CO2 atmosphere and 95% humidity. Cell extracts were prepared, followed by immunoprecipitation and immunoblotting with specific anti-pIGF-IR, anti-pERK1/2 and anti-pAkt antibodies. Results. After 5 minute stimulation with IGF-I, 70% of the IGF-IR was phosphorylated in the cell line CSC 1595 and 25% in MCF-7. In addition, Akt (oncogene protein v-akt) and ERK1/2 (extracellular signal-regulated MAP kinases) were phosphorylated. Basal and stimulated levels of phosphorylated ERK1/2 were substantially higher compared to those in the MCF-7 cell line. Conclusions. The IGF-IR and MAPK kinase pathway involving proteins ERK1/2 showed more significant phosphorylation in the 1,595 cells compared to the observed in the MCF-7 cell line. Since the IGF-IR is the major activator of this pathway it may play an important role in ductal infiltrating breast cancer tumor growth and metastases.


Assuntos
Neoplasias da Mama , Linhagem Celular , Mitógenos
7.
Braz. j. med. biol. res ; 41(9): 773-781, Sept. 2008. graf, tab
Artigo em Inglês | LILACS | ID: lil-492884

RESUMO

Blomia tropicalis, Dermatophagoides pteronyssinus and D. farinae are prevalent house dust mites. Concanavalin A-binding components derived from B. tropicalis (Bt-ConA extract) are highly immunogenic in allergic diseases. The aim of the present study was to evaluate the humoral and cellular immune responses to B. tropicalis in mite-sensitized patients. A total of 137 patients with allergic rhinitis with/without asthma and 109 non-atopic subjects were selected and analyzed by the skin prick test, and for total serum IgE and specific IgE levels to both Bt-total and Bt-ConA extracts, their proliferative response and cytokine (IFN-ã and IL-5) production by peripheral blood mononuclear cells (PBMC) stimulated with both extracts. Skin prick test showed that 70 percent of the patients were sensitized to Bt (Bt+) and similar levels of specific IgE to Bt-total and Bt-ConA extracts were demonstrable in Bt+ patients. Significant PBMC proliferation was observed in response to Bt-total extract in Bt+, but not in Bt- patients and non-atopic subjects (P < 0.001). Bt-ConA extract induced increased proliferative responses in all patient groups compared to medium alone (P < 0.05), but these responses were significantly decreased in the presence of the mannopyranoside ConA inhibitor (P < 0.05). Significant IFN-ã production was observed after Bt-ConA stimulation of Bt+ patients (P < 0.05), while Bt-total extract had no effect. IL-5 production was consistently detected in Bt+ patients after allergen-specific stimulation or with no stimulus, indicating that PBMC from allergic patients are prone to produce Th2 profile cytokines, spontaneously or inductively by allergen restimulation. These data showed that ConA-binding components isolated from B. tropicalis may contain relevant antigens that are involved in both humoral and cellular immune responses. However, without an additional purification procedure to eliminate the residual contamination with...


Assuntos
Adulto , Animais , Feminino , Humanos , Masculino , Alérgenos/administração & dosagem , Antígenos de Dermatophagoides/administração & dosagem , Concanavalina A/administração & dosagem , Mitógenos/administração & dosagem , Rinite Alérgica Perene/imunologia , Alérgenos/imunologia , Antígenos de Dermatophagoides/imunologia , Estudos de Casos e Controles , Proliferação de Células , Concanavalina A/imunologia , Dessensibilização Imunológica , Imunoglobulina E/sangue , Imunoglobulina E/imunologia , Interferon gama/biossíntese , /biossíntese , Leucócitos Mononucleares/imunologia , Ácaros/imunologia , Mitógenos/imunologia , Rinite Alérgica Perene/sangue
8.
Rev. Soc. Bras. Med. Trop ; 41(4): 325-329, jul.-ago. 2008. ilus, graf
Artigo em Inglês | LILACS | ID: lil-494483

RESUMO

In this study, we evaluated the profile of anti-Paracoccidioides brasiliensis immunoglobulin isotypes in serum from patients with the acute and chronic forms of paracoccidioidomycosis, using the whole Paracoccidioides brasiliensis antigen and the antigen treated with sodium metaperiodate. All the immunoglobulin isotypes present in the serum from patients with the acute and chronic forms of paracoccidioidomycosis presented higher reactivity towards the whole antigen than to the antigen treated with metaperiodate (P < 0.05). The reactivity of IgG and IgM to the antigen treated with metaperiodate was greater in serum from patients with the acute form of the disease (P < 0.05), while IgA was more reactive in serum from patients with the chronic form (P < 0.05). There was greater reactivity of IgG1 and IgG2 to the whole antigen and the antigen treated with metaperiodate in the serum from patients with paracoccidioidomycosis than there was in serum from patients with other parasitic infections (P < 0.05). Furthermore, IgG1 from patients with the acute form recognized the 19kDa, 27kDa and 31kDa antigens in the western blot test. Thus, the results suggest that modifications to the epitopes of Paracoccidioides brasiliensis antigens may help to improve the immunodiagnosis of paracoccidioidomycosis.


Neste trabalho, foi avaliado o perfil de isotipos de imunoglobulinas anti-Paracoccidioides brasiliensis em soros de pacientes com formas crônica e aguda de paracoccidiodomicoses usando antígeno total e tratado com meta-periodato. Todos os tipos de imunoglobulinas presentes nos soros de pacientes com formas aguda e crônica apresentaram alta reatividade ao antígeno total quando comparado ao tratado com meta-periodato (P < 0,05). Houve maior reatividade de IgG e IgM anti-antígeno tratado com meta-periodato em soros de pacientes com forma aguda da doença (P < 0,05), enquanto IgA foi mais reativa em soros da forma crônica (P < 0,05). Houve maior reatividade de IgG1 e IgG2 com antígeno total e tratado com meta-periodato em soros de pacientes comparados aos com outras parasitoses (P < 0,05). Além disso, IgG1 de pacientes com a forma aguda reconhecem antígenos de 19kDa, 27kDa e 31kDa por western blot. Assim, os resultados sugerem que alterações nos epitopos de antígenos de Paracoccidioides brasiliensis podem auxiliar no aprimoramento do imunodiagnóstico da paracoccidioidomicose.


Assuntos
Humanos , Anticorpos Antifúngicos/imunologia , Antígenos de Fungos/imunologia , Isotipos de Imunoglobulinas/imunologia , Paracoccidioides/imunologia , Paracoccidioidomicose/imunologia , Doença Aguda , Anticorpos Antifúngicos/sangue , Anticorpos Antifúngicos/efeitos dos fármacos , Reações Antígeno-Anticorpo/efeitos dos fármacos , Reações Antígeno-Anticorpo/imunologia , Antígenos de Fungos/sangue , Antígenos de Fungos/efeitos dos fármacos , Western Blotting , Estudos de Casos e Controles , Doença Crônica , Epitopos/efeitos dos fármacos , Epitopos/imunologia , Isotipos de Imunoglobulinas/sangue , Isotipos de Imunoglobulinas/efeitos dos fármacos , Mitógenos/uso terapêutico , Paracoccidioides/efeitos dos fármacos , Paracoccidioidomicose/sangue , Paracoccidioidomicose/tratamento farmacológico , Ácido Periódico/uso terapêutico
9.
Braz. j. med. biol. res ; 40(8): 1111-1120, Aug. 2007. graf
Artigo em Inglês | LILACS | ID: lil-456804

RESUMO

Aging is accompanied by a decrease in several physiological functions that make older individuals less responsive to environmental challenges. In the present study, we analyzed the immune response of female BALB/c mice (N = 6) of different ages (from 2 to 96 weeks) and identified significant age-related alterations. Immunization with hapten-protein (trinitrophenyl-bovine serum albumin) conjugates resulted in lower antibody levels in the primary and secondary responses of old mice (72 weeks old). Moreover, young mice (2, 16, and 32 weeks old) maintained specific antibodies in their sera for longer periods after primary immunization than did old mice. However, a secondary challenge efficiently induced memory in old mice, as shown by the increased antibody levels in their sera. The number of CD4+ and CD8+ T cells in the spleen increased until 8 weeks of age but there was no change in the CD4+/CD8+ ratio with aging. Splenic T cells from old mice that had or had not been immunized were less responsive to concanavalin-A and showed reduced cytokine production compared to young mice (IL-2: 57-127 vs 367-1104 pg/mL, IFN-g: 2344-12,836 vs 752-23,106 pg/mL and IL-10: 393-2172 vs 105-2869 pg/mL in old and young mice, respectively). These data suggest that there are significant changes in the organization of the immune system throughout life. However, the relevance of these alterations for the functioning of the immune system is unknown.


Assuntos
Animais , Feminino , Camundongos , Envelhecimento/imunologia , Citocinas/biossíntese , Haptenos/imunologia , Baço/imunologia , Subpopulações de Linfócitos T/imunologia , Proliferação de Células/efeitos dos fármacos , Concanavalina A/farmacologia , Imunidade Celular/imunologia , Camundongos Endogâmicos BALB C , Mitógenos/farmacologia , Baço/citologia
10.
Perionews ; 1(2): 133-140, abr.-jun. 2007. ilus, tab
Artigo em Português | LILACS, BBO - Odontologia | ID: biblio-836849

RESUMO

Fatores de crescimento polipeptídicos são proteínas de baixo peso molecular sintetizadas por várias células e tecidos que regulam os eventos básicos que levam à regeneração periodontal: proliferação, quimiotaxia, diferenciação e síntese de matriz protéica. Embora diversos métodos terapêuticos tenham sido propostos para uso clínico visando a regeneração dos tecidos periodontais, a previsibilidade de sucesso ainda é limitada, com casos bem-sucedidos e outros mostrando resultados aquém do esperado. Recentemente, após a identificação da existência de células tronco no ligamento periodontal e a compreensão que a diferenciação destas células em outras mais diferenciadas (fibroblastos, osteoblastos e cementoblastos) é mediada por moléculas de sinalização (fatores de crescimento), alguns estudos foram publicados propondo a utilização clínica dos fatores de crescimento, isolados ou combinados, em diferentes tipos de veículos com o objetivo de favorecer a regeneração periodontal. Neste artigo, as características gerais e os estudos in vitro e in vivo evidenciando o papel dos principais fatores de crescimento utilizados na regeneração periodontal serão revistos com o objetivo de avaliar o papel dos fatores de crescimento na regeneração periodontal.


Polipeptidic growth factors are low density proteins secreted by different cells and tissues that regulate the basic events leading to periodontal regeneration: proliferation, chemotaxis, differentiation and protein synthesis. Although many methods for achieving regeneration of lost periodontal tissues have been suggested, there is poor predictability, with some well-succeeded cases and others showing unexpected results. Recently, after the identification of mesenchymal stem cells in the periodontal ligament and the understanding that the differentiation of these cells onto more differentiated ones (osteoblasts, cementoblasts, fibroblasts) is mediated by signaling molecules (growth factors), some studies have proposed the clinical use of growth factors isolated or in combination to enhance periodontal regeneration outcomes. In this paper, the characteristics and in vitro and the in vivo studies evaluating the role of growth factors in periodontal regeneration will be reviewed to evaluate the role of growth factors in periodontal regeneration.


Assuntos
Humanos , Quimiotaxia , Regeneração Tecidual Guiada Periodontal , Peptídeos e Proteínas de Sinalização Intercelular , Mitógenos , Periodontia
11.
Braz. dent. j ; 18(1): 40-44, 2007. ilus, graf
Artigo em Inglês | LILACS | ID: lil-461435

RESUMO

Sjögren's syndrome is an autoimmune disease characterized by sialoadenitis and elevated titers of autoantibodies. To assess whether it is possible to induce inflammatory changes in salivary gland tissues, a series of immunizations in Balb/c mice have been undertaken, using salivary gland extract, modified or not, added to several adjuvants. Mice's humoral immune response to salivary gland antigens was monitored by ELISA. Inflammatory cells infiltrating gland tissue were seen 3 months after immunization with salivary gland extract modified with pepsin (AgGp) and metaperiodate (AgGMp). Although pathological progression was not observed, the histopathological picture was similar to the initial phase of Sjõgren's syndrome. In addition, a monoclonal antibody reactive with 3 gland polypeptides and anhydrase carbonic II was rescued among B cells from immunized mice. Thus, immunizations with modified autoantigens were able to initiate pathological damage to glandular tissue and stimulate the proliferation of auto-reactive B cells.


A Síndrome de Sjögren é uma doença auto-imune caracterizada por desenvolvimento de sialoadenite e títulos elevados de auto-anticorpos. Com o objetivo de induzir alterações inflamatórias no tecido das glândulas salivares foram realizadas várias imunizações em camundongos BALB/c utilizando extratos de glândulas salivares, modificados ou não, em vários adjuvantes. A resposta humoral para antígenos salivares foi monitorada por ELISA. Células inflamatórias infiltrando o tecido glandular foram vistas 3 meses pós-imunização com extrato de glândula salivar modificado com pepsina (AgGp) e metaperiodato (AgGMp). Embora a evolução patológica não tenha sido observada, o quadro histopatológico foi semelhante à fase inicial da Síndrome de Sjõgren. Também foi possível notar, a partir das células B dos animais imunizados, a produção de anticorpos monoclonais reativos com 3 polipeptídeos glandulares e anidrase carbônica II. Assim, a imunização com auto-antígenos glandulares modificados foi capaz de iniciar o processo patológico no tecido glandular e induzir a proliferação de células B produtoras de auto-anticorpos.


Assuntos
Animais , Bovinos , Feminino , Camundongos , Glândulas Salivares/imunologia , Sialadenite/imunologia , Vacinação , Autoantígenos/efeitos adversos , Hibridomas/imunologia , Camundongos Endogâmicos BALB C , Mitógenos/efeitos adversos , Ácido Periódico/efeitos adversos , Glândulas Salivares/patologia , Sialadenite/patologia , Síndrome de Sjogren/imunologia , Síndrome de Sjogren/patologia
12.
Arch. alerg. inmunol. clin ; 36(2): 35-40, abr. 2005. ilus, tab
Artigo em Espanhol | LILACS | ID: lil-410879

RESUMO

Antecedentes. La decocción y el aceite esencial de Minthostachys verticillata han demostrado efectos antimicrobianos sobre el género Staphylococcus y propiedad antiherpéticas. Objetivos. Determinar la capacidad inmunogénica de la decocción vegetal en inmunizaciones experimentales. Investigar la capacidad proliferativa de linfocitos estimulados con derivados de M. verticillata. Evaluar los efectos de la dococción sobre el mitógeno pokeweed (PWM). Detectar y cuantificar LT CD8+ y LB en células proliferadas provenientes de niños alérgicos con infección VHS-1. Materiales y métodos. Se inmunizaron 2 conejos con la decocción. Se evaluaron los anticuerpos por precipitación y hemaglutinación pasiva. Se estudió la proliferación de linfocitos de 25 pacientes de 2 a 14 años, 15 alérgicos con lesiones de Herpes Simplex Tipo 1 (VHS-1) y 10 controles. Las células fueron estimuladas con a) decocción, b) aceite esencial, c) PWM, d) decocción + PWM, e) control. Se caracterizaron y cuantificaron LT CD8+ y LB por IFD. Resultados. La decocción indujo la síntesis de anticuerpos no precipitantes y hemaglutinantes de glóbulos rojos de carnero. Los linfocitos de los pacientes con VHS-1 mostraron niveles linfoproliferativos más elevados(p<0,01). La decocción y el aceite mostraron efectos mitogénicos similares a PWM. El agregado simultáneo de decocción y PWM redujo la proliferación alcamzada por cada uno (p<0,001) tanto en infectados como en controles. Entre células proliferadas se caracterizaron LT CD8+ y LB. Conclusión. La decocción fue inmunogénica, los anticuerpos tuvieron características de coprecipitantes. Los derivados de M. verticillata mostraron propiedades mitogénicas similares a PWM. La decocción inhibió los efectos de PWM


Assuntos
Humanos , Pré-Escolar , Adolescente , Coelhos , Lactente , Criança , Mitógenos , Plantas Medicinais , Adjuvantes Imunológicos , Linfócitos B , Linfócitos T CD8-Positivos , Sistema Imunitário
13.
São Paulo; s.n; 2005. 133 p. ilus, tab, graf.
Tese em Português | LILACS | ID: lil-425825

RESUMO

O objetivo desta tese é estudar o papel de FGF2 no controle do ciclo celular em células de mamíferos. Nosso principal modelo, a linhagem Y1, é derivada de um tumor funcional de córtex de camundongo que possui o proto-oncogene c-ki-ras amplificado, tendo consequentemente a super-expressão da proteína c-Ki-Ras na forma ativa (c-Ki-Ras-GTP). Células Y1 sincronizadas na interface GO G1 do ciclo celular são prontamente responsivas a tratamentos de FGF2 (fator de crescimento de fibroblasto-2) sendo este capaz de ativar toda a progressão GO G1 S do ciclo celular, mas surpreendentemente , sob estas mesmas condições, FGF2 induz em cultura e in vivo morte celular nesta linhagem, bloqueando o progresso no ciclo após a entrada na fase S. Sob condições induzidas de abaixo c-Ki-Ras-GTP, células Y1 respondem à FGF2 com um aumento na proliferação, mostrando que a indução de morte nesta linhagem está diretamente relacionado com os níveis de Ki-Ras-GTP...


Assuntos
Camundongos , Animais , Expressão Gênica , Mitógenos , Biologia Molecular , Oncogenes , Receptores de Fatores de Crescimento de Fibroblastos , Ciclo Celular , Morte Celular , Linhagem Celular , Células Clonais , Fibroblastos , Células Tumorais Cultivadas
14.
São Paulo; s.n; 2005. 140 p. ilus, tab, graf.
Tese em Português | LILACS | ID: lil-407962

RESUMO

A proteína de fase aguda, amilóide sérica A (SAA), exerce função importante na resposta inflamatória, estimulando a expressão e a liberação de TNF-`alfa´-IL-8 e IL-8 e IL-1ß em neutrófilos e células mononucleares (1, 2, 3, 4). Visando obter mais informação sobre o processo, estudamos as vias de sinalização envolvidas na liberação dessas citocinas, após as células serem estimuladas com SAA. Para tal, avaliamos o efeito de alguns inibidores da cascata de sinalização e evidenciamos indiretamente a participação das proteínas quinases ativadas por mitógenos (MAPK) e da fosfatidil inositol 3 quinase (PI3K) (2, 3). Com a utilização de inibidores específicos, observamos que há inibição da liberação de IL-8 quando utilizamos um antagonista da proteína Gi e observamos também a participação do fator de transcrição, NF-`capa´B na liberação de IL-8 e TNF-`alfa´ promovida por SAA...


Assuntos
Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Citocinas , Diabetes Mellitus Tipo 2 , Espécies Reativas de Oxigênio , Leucócitos , Neutrófilos , Proteína Amiloide A Sérica , Fator de Necrose Tumoral alfa , Doença Granulomatosa Crônica , Mitógenos , Concentração Osmolar
15.
Rev. Fac. Cienc. Méd. (Córdoba) ; 60(1): 19-24, 2003. tab
Artigo em Espanhol | LILACS | ID: lil-441445

RESUMO

Se estudió in vitro el efecto de gangliósidos sobre las respuestas de linfocitos de pacientes chagásicos estimulados con mitógenos o con antígenos de corazón y cerebro. La razón para efectuar este estudio fueron las evidencias que indican un rol de los linfocitos T en la producción de daños de la cardiopatía chagásica, y datos que indican que los gangliósidos pueden tener actividad sobre esas células. Además, en trabajos previos, hallamos que los linfocitos de chagásicos responden con transformación blástica (TB). Material y Métodos: se efectuaron cultivos de leucocitos de 14 pacientes chagásicos. A los cuales se adicionaron gangliósidos y en esas condiciones, se estimularon con mitógenos, o bien con antígenos de corazón humano o cerebro murino, respectivamente. Resultados: se observó inhibición parcial de la transformación blástica Inducida por mitógenos, y también hubo Inhibición parcial de la TB inducible por los antígenos de corazón o de cerebro en los linfocitos de chagásicos, siendo significativas las diferencias con respecto a los controles (p< 0.001). Conclusiones: se considera de Interés ese efecto inhibidor de gangliósidos sobre las actividades de los linfocitos de chagásicos estudiadas en estos experimentos, por ser directamente vinculables a factores de patogenia chagásica, que podrían ser Inmunomodulados.


In human Chagas'disease previous work has shown the occurrence of a T-lymphocyte CD4-positive population (a high producer of PAS-positive glycoproteins) with evidence suggesting a role in the formation of damages to the myocardium and neural structures in chagasic heart disease (ChHD). Other workers have taken such facts into consideration and have employed gangliosides (biological substances with neurotrophic and immunomodulatory properties) in chagasics with chronic cardiomyopathy and disautonomic signs, obtaining an Improvement in functional signs and a decrease in the number of PAS+ lymphocytes. In the present work we have studied the effect of mixed gangliosides (Cronassial on cell cultures of total leukocytes, or on mononuclear cells prepared through Ficoll-Hypaque. Blood was obtained from 14 patients with ChHD. Experiments were undertaken to assess the effect of policlonal mitogens Phytohaemagglutinin (Phy) and Concanavalin A (Con A) on blastic transformation, estimated by cell size and cytologic study. In addition, the production of PAS+ substances by the lymphocytes and blast were assessed. Gangliosides were added at final concentrations of 100 mg/ml or 200 mg/ ml. Cell viability was assessed by means of the Trypan blue test. With respect to blastic transformation, results showed a significant decrease in the cultures that received gangliosides 24 hours before mltogen administration, as compared with controls (p<0.001) (both for Phy and Con A). On the other hand, the production of lymphocytic PAS+ substances decreased in the cultures of chagasics in which gangliosides were added. Some of these results confirmed previous findings on the matter. The facts suggest that gangliosides can modulate some lymphocytic activities in chagasics.


Assuntos
Humanos , Cardiomiopatia Chagásica/imunologia , Doença de Chagas/imunologia , Gangliosídeos/farmacologia , Técnicas In Vitro , Miocárdio , Mitógenos/farmacologia , Linfócitos T/imunologia , Estudos de Casos e Controles , Células Cultivadas , Cardiomiopatia Chagásica/patologia , Miocárdio/química , Miocárdio/imunologia , Linfócitos T/efeitos dos fármacos
17.
Arch. med. res ; 30(4): 298-302, jul.-ago. 1999. graf
Artigo em Inglês | LILACS | ID: lil-266533

RESUMO

Background. Several factors inhibit cellular immune response by deactivating macrophages, but very few, such as those described here, prevent macrophage activation. Methods. Ascites liquid from 12-day-old BALB/c mice bearing 5178Y lymphoma tumors was collected, and cell-free ascites liquid (CFAL) was separated from lymphoblasts. The supernatant (SI) was obtained from the homogenized and centrifuged lymphoblasts Then, macrophage cultures contaning 0.2 X 10 a the sixth cells from lymphoma-bearing or hearthly mice were added to 10 µL of CFAL or S1, plus 5 µg of lipopolysaccharides (LPS)/mL, 40 U interferon-ç or a blend of both. Macrophages were incubated with CFAL or S1 prior to or after adding the activators to investigate whether any of the previously mentioned lymphoma fraction inhibited macrophage activation or whether they deactivated them. The effect of CFAL or S1 was estimated as the diminution of the amount of nitric ixide released by the experimental macrophage cultures with respect to controls (activated macrophages treated with none of the lymphoma fractions). Results. LPS, IFN-ç, and the LPS/ç blend activated macrophages from both lymphomabearing and healthy mice. None of the lymphoma fractions deactivated macrophages. CFAL, but not S1, inhibited the macrophage activation, i.e., the percentage of inhibition of nitric oxide releasing 76.7 percent in macrophages from healthy and lymphomabearing mice, respectively. In addition, CFAL was unable to inhibit macrophage-activation effect of IFN-ç or the LPS/IFN-ç blend. Conclusions. Mouse L5178Y Lymphoma releases a factor that in vitro inhibits the macrophage activation induced by LPS, but not by IFN-ç controls


Assuntos
Animais , Masculino , Camundongos , Ativação de Macrófagos/imunologia , Linfoma/imunologia , Macrófagos/imunologia , Interferon-alfa/farmacologia , Lipopolissacarídeos/farmacologia , Macrófagos/citologia , Macrófagos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos DBA , Mitógenos/farmacologia
18.
Rev. bras. biol ; 59(3): 517-525, Aug. 1999.
Artigo em Inglês | LILACS | ID: lil-320821

RESUMO

Bioassays were performed to assess the effects of different levels of growth medium supplementation with fetal bovine serum (FBS), fish fry extract (FE), combinations of FBS and FE, and addition of insulin-like growth factor I (IGF-I) and fibroblast growth factor (FGF) on the proliferation of brown bullhead catfish cells (BB line). Treatments (n = 4) were: 2.5, 5, 10, and 15.0 FBS or FE and 5/2.5, 5/5, 10/2.5, and 10/5 of a FBS/FE combination as supplement to the growth medium, or the addition of 0.1, 1, 2.5, 10, 25, and 75 ng/ml of either IGF-I or FGF to the growth media. Initial cell density was 1.1 x 10(6) cells per well on uncoated 24-well plates. Incubation temperature was 29.5 +/- 0.7 degrees C. Six hours after plating, initial culture medium was removed, plates rinsed with Dulbecco's phosphate buffered saline, treatment media added, and cells allowed to proliferate for 24 hours. Another bioassay was performed with rat myoblast omega cells (RMo) using the same levels of growth medium supplemented with FBS, FE and FBS/FE. Base growth medium was Dulbecco's MEM. The initial cell density was 7.2 x 10(6) cells per well, and the bioassay was carried out at 36.0 +/- 0.5 degrees C, on a 95 air, 5 CO2 incubator. Increasing levels of FBS had a positive effect (P < 0.05) on the proliferation of both BB and RMo cells. Increasing levels of FE had a negative effect (P < 0.05) on the proliferation of BB cells and totally inhibited the proliferation of RMo cells at any level of supplementation. Higher levels of FE on the FBS/FE combinations presented a negative effect on the proliferation of both BB and RMo cells (P < 0.05). Insulin-like growth factor I had a positive quadratic effect (P < 0.05) on the proliferation of BB cells. Apparently, mammalian growth factors slightly stimulated mitogenic activity in fish cells, while FE contained factors which inhibited the mitogenic activity of RMo and BB cell lines.


Assuntos
Animais , Bovinos , Ratos , Sangue Fetal , Fatores de Crescimento de Fibroblastos , Ictaluridae , Fator de Crescimento Insulin-Like I , Mitógenos/farmacologia , Extratos de Tecidos , Bioensaio , Linhagem Celular , Meios de Cultura , Divisão Celular/efeitos dos fármacos , Óvulo/fisiologia
19.
Rev. colomb. biotecnol ; 2(1): 40-49, jul. 1999. ilus, graf
Artigo em Espanhol | LILACS | ID: lil-506976

RESUMO

En este trabajo se evalúan diferentes técnicas para obten-ción y cultivo de células de Schwann provenientes del nervio periférico de rata adulta, de las cuales la que evi-dencia mejor respuesta es la que combina una degenera-ción walleriana durante 14 días in vitro, seguida de una disociación enzimática.La adición de mitógenos como la forskolina y extracto de pituitaria no muestra un efecto sobre estas células. Los niveles de enriquecimiento en células de Schwann, defi-nidos de acuerdo con patrones morfológicos y de expre-sión de marcadores tales como la proteína S-100 o la pro-teína acida fíbrilar glial (GFAP), son buenos (del orden de 80-88por cien) hasta los ocho días de cultivo. La detección de bromodeoxiouridina (BrdU) incorporada por células en fase S del ciclo celular, demuestra que en términos ge-nerales la tasa de incorporación de BrdU de las células guales del sistema nervioso periférico no cambia.


Assuntos
Fármacos do Sistema Nervoso Periférico , Técnicas de Cultura de Células , Mitógenos , Regeneração Nervosa , Células de Schwann , Engenharia Tecidual
20.
Reproducción ; 12(3): 133-40, 1997. ilus, tab
Artigo em Espanhol | LILACS | ID: lil-226740

RESUMO

Objetivo: Evaluar y comparar el efecto mitogénico del fluido peritoneal de mujeres con endometriosis mínima y severa sobre la proliferación de células estronales endometriales en cultivo. Materiales y Métodos: Se establecieron cultivos primarios de células estronales de endometrio humano. Se agregaron concentraciones crecientes de fluido peritoneal de pacientes con endometriosis mínima y severa, y de controles. Se evaluó incorporación de Timidina tritiada (3[H]-Timidina) como parámetro de síntesis de ADN en esas células. Resultados: El fluido peritoneal de mujeres con endometriosis mínima indujo un incremento significativo y dosis-dependiente de la incorporación de 3[H]-Timidina que osciló entre el 580 por ciento y el 1450 por ciento de los controles. El fluido peritoneal de pacientes con endometriosis severa provocó una inhibición del 51 por ciento en promedio de la proliferación celular comparando con células que fueron expuestas a fluidos peritoneales controles o a medio de cultivo suplementado con 2,5 por ciento de suero bovino fetal. Conclusiones: Se hallaron diferencias significativas en cuanto al efecto mitogénico del fluido peritoneal de pacientes con distintos estadíos de endometriosis. Las muestras provenientes de pacientes con endometriosis mínima indujeron un incremento de la proliferación celular, mientras que el fluido peritoneal de endometriosis severa inhibió significativamente el crecimiento de las células endometriales en cultivo


Assuntos
Humanos , Feminino , Adulto , Endometriose/fisiopatologia , Líquido Ascítico/citologia , Mitógenos/análise , Técnicas de Cultura de Células , Células Estromais , Endometriose/classificação , Líquido Ascítico/citologia , Líquido Ascítico/química , Timidina
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