Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 6 de 6
Filtrar
1.
Front Immunol ; 9: 3158, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30713536

RESUMO

Helminth infections and allergies are characterized by a predominant type-2 immune response. In schistosomiasis, the Th-2 response is usually accompanied by induction of immunoregulatory mechanisms that contribute to worm survival and less severe schistosomiasis. Although helminth-induced immunomodulatory mechanisms seem to affect atopy, epidemiological studies on the relationship between helminths and allergy have been inconsistent, and data suggest that the modulatory effects may be influenced by helminth species, chronicity of infection, and parasite burden. Here we performed a cross-sectional study to investigate the effects of Schistosoma mansoni parasite burden and immune response on allergic reactivity of individuals living in a schistosomiasis endemic area in Brazil. Fecal samples from the participants were collected for extensive parasitological examinations by spontaneous sedimentation, Kato-Katz, Helmintex and Saline Gradient tests and molecular detection of S. mansoni by qPCR. Additionally, the concentrations of cytokines and chemokines, total IgE and IgE-reactivity to common house dust allergens were quantified from serum samples. IgE reactivity to dust allergens was detected in 47 individuals (23.8%), and 140 individuals (54.4%) were diagnosed with S. mansoni infection. Most of the infected population (108 individuals) presented very low parasite burden (≤12 eggs/g of feces). The frequency and intensity (p ≤ 0.03) of allergic reactivity were lower in S. mansoni-infected compared with non-infected individuals. Multivariable logistic regression models adjusted by age revealed that allergic reactivity was positively associated with low IL-10 response (OR, 4.55, 95% CI, 0.56-7.36) and high concentration of the inflammatory mediators IL-33 (OR, 2.70, 95% CI, 1.02-7.15) or TNF-α (OR, 6.88, 95% CI, 0.32-143.39) in serum, and inversely associated with S. mansoni infection (OR, 0.38, 95% CI, 0.16-0.87). Most importantly, the logistic regression demonstrated that the modulatory effects of Schistosoma infection depend on parasite burden, with individuals infected with ≤12 eggs/g of feces showing allergic IgE-reactivity similar to non-infected individuals Altogether, our data show that immunomodulation of allergic reactivity depends on S. mansoni burden, low type-2 inflammatory response, and high level of IL-10.


Assuntos
Antígenos de Helmintos/imunologia , Citocinas/sangue , Hipersensibilidade/imunologia , Imunomodulação , Carga Parasitária , Schistosoma mansoni/imunologia , Esquistossomose mansoni/imunologia , Esquistossomose mansoni/parasitologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Brasil/epidemiologia , Criança , Pré-Escolar , Estudos Transversais , Poeira/imunologia , Feminino , Humanos , Hipersensibilidade/epidemiologia , Imunoglobulina E/sangue , Imunoglobulina E/imunologia , Interleucina-10/sangue , Interleucina-33/sangue , Masculino , Pessoa de Meia-Idade , Esquistossomose mansoni/epidemiologia , Fator de Necrose Tumoral alfa/sangue , Adulto Jovem
2.
Front Immunol ; 9: 2975, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30619332

RESUMO

Intestinal schistosomiasis, caused by the parasitic trematode Schistosoma mansoni, is a chronic disease and the prolonged and continuous exposure to S. mansoni antigens results in a deviation of the host's immune response. For diagnosis, the Kato-Katz (KK) method is recommended, however, this method showed low accuracy in areas of low endemicity. This study aimed to characterize the cytokine and chemokine profile of individuals with an extremely low parasite load (<4 eggs per gram of feces), e.g., individuals who were detected by alternative parasitological methods, such as the saline gradient and/or Helmintex®. In order to search for immunological markers for infection, the immunological profile in serum samples of these individuals was then compared with patients detected with the KK method and with a higher parasite load and with individuals repetitively negative by extensive stool exams. The study was conducted in Northern Minas Gerais in a rural area of the Municipality of Januária. Serum samples of a total of 139 parasitologically well-characterized individuals were assessed for the following immunological markers by commercially available immunoassays: TNF-α, IL-1ß, IL-6, IL-17A, IL-5, IL-10, IL-13, IL-33, IL-27, CCL3, CCL5, CXCL10, CCL11, and CCL17. As a result, there were no significant differences in concentrations or frequencies for immunological markers between egg-negative individuals or individuals with ultra-low (<4 epg) or low (4-99 epg) parasite loads. However, we found significant correlations between egg counts and eosinophil counts and between egg counts and IL-1ß or TNF-α concentrations. The most striking alterations were found in individuals with the highest parasite load (≥100 epg). They had significantly higher TNF-α concentrations in serum when compared with individuals with a low parasite load (4-99 epg) and CCL17 concentrations were significantly elevated when compared with egg-negative individuals. Radar diagrams of frequencies for cytokine and chemokine responders in each infection group confirmed a distinct profile only in the infection group with highest parasite loads (≥100 epg).


Assuntos
Antígenos de Helmintos/imunologia , Citocinas/sangue , Eosinófilos , Schistosoma mansoni/imunologia , Esquistossomose mansoni/imunologia , Adolescente , Adulto , Animais , Contagem de Células Sanguíneas , Brasil/epidemiologia , Citocinas/imunologia , Doenças Endêmicas , Fezes/parasitologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Contagem de Ovos de Parasitas , Esquistossomose mansoni/sangue , Esquistossomose mansoni/epidemiologia , Esquistossomose mansoni/parasitologia , Adulto Jovem
3.
Pesqui. vet. bras ; 37(3): 205-209, Mar. 2017. tab.
Artigo em Português | LILACS, VETINDEX | ID: biblio-842067

RESUMO

Com o objetivo de diagnosticar a situação do complexo teníase-cisticercose bovina no município de Salinas, Minas Gerais, foram coletadas amostras de sangue de 355 bovinos distribuídos em 18 propriedades rurais, sorteadas aleatoriamente. Em cada propriedade, foi aplicado um questionário socioeconômico para a análise de fatores que favorecem a manutenção do complexo teníase-cisticercose bovina. Foi realizado também um levantamento epidemiológico dos casos de teníase diagnosticados nos laboratórios credenciados pela Secretaria Municipal de Saúde de Salinas, no período de 2007 a 2010. A prevalência de cisticercose bovina foi de 4,70% enquanto as prevalências de teníase, encontradas durante os quatro períodos avaliados, foram de 0,29%, 0,36%, 0,24% e 0,24%. Entre os fatores de risco para a manutenção do complexo teníase-cisticercose analisados, foi observada uma relação estatisticamente significativa entre a ocorrência de cisticercose bovina e a ingestão de carne malpassada pelos entrevistados. Foi concluído que a cisticercose bovina está presente no município de Salinas, Minas Gerais, sendo o tratamento térmico ineficiente da carne bovina o principal fator de risco para a manutenção do complexo teníase-cisticercose, o que reforça a necessidade da adoção de medidas de controle com contínua vigilância epidemiológica e sanitária.(AU)


In order to diagnose the situation of bovine taeniasis-cysticercosis complex in the municipality of Salinas, Minas Gerais, Brazil, blood samples were collected from 355 cattle in 18 randomly selected farms. A socioeconomic questionnaire was filled in each farm for the analysis of factors which favor the maintenance of the taeniasis-cysticercosis complex. An epidemiological survey of human taeniasis was performed through analyses of the Municipal Health Department in the 2007-2010 period. A prevalence of 4.7% for bovine cysticercosis and the frequency of 0.29, 0.36, 0.24 and 0.24% for human taeniasis, during the evaluated period, was found. Among the risk factors, a statistically significant correlation was found between the occurrence of bovine cysticercosis and the ingestion of undercooked meat. It was concluded that bovine cysticercosis is present in the municipality of Salinas, due to inefficient heat treatment of the meat as the main risk factor for maintenance of the taeniasis-cysticercosis complex, reinforcing the need to adopt control measures with continuous epidemiological and health surveillance.(AU)


Assuntos
Animais , Bovinos , Cisticercose/diagnóstico , Teníase/diagnóstico , Ensaio de Imunoadsorção Enzimática/veterinária , Estudos Epidemiológicos , Immunoblotting/veterinária
4.
Bioorg Med Chem ; 23(9): 2053-61, 2015 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-25813896

RESUMO

New O-isoprenylated-N-methylarylnitrones derived from isomeric o, m and p-hydroxybenzaldehydes have been prepared and the antineoplastic effects on human cancer cell lines were evaluated. The O-geranylated nitrone LQB-278 (1b) and its isomers 2b and 3b inhibited the NO production, but the anti-leukemic activity was drastically dependent on nitrone isomer, with the 1b being the most effective one (IC50 of 6.7 µM) on Jurkat leukemia cell, by MTT assay. In addition, 1b up-regulated p21CIP1/WAF1/Sdi1 protein expression (flow cytometry), a cell cycle inhibitor, reduced cell growth, and induced DNA fragmentation (increased sub-G1 phase cells) and phosphatidylserine externalization in plasmatic membrane (increased annexin V positive cells). Finally, the 1b up-regulation of p21 expression and apoptosis induction seem to be the mechanisms by which it promotes its anti-leukemic effects, making this new molecular architecture a promising prototype for leukemia intervention.


Assuntos
Antineoplásicos/síntese química , Antineoplásicos/farmacologia , Benzaldeídos/química , Óxidos de Nitrogênio/síntese química , Óxidos de Nitrogênio/farmacologia , Animais , Antineoplásicos/química , Apoptose/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Células K562 , Camundongos , Estrutura Molecular , Células NIH 3T3 , Óxido Nítrico/antagonistas & inibidores , Óxido Nítrico/biossíntese , Óxidos de Nitrogênio/química , Relação Estrutura-Atividade
5.
ROBRAC ; 23(66)set 2014. ilus, tab
Artigo em Português | LILACS | ID: lil-763963

RESUMO

Objetivo: A exposição da membrana durante procedimentos regenerativos periodontais pode causar contaminação e complicações pós-operatórias. Este estudo avaliou a capacidade de uma membrana absorvível atuar como carreador de quimioterápicos. Material e Métodos: Noventa amostras de membranas absorvíveis de origem xenógena, da marca Genius/Baummer, foram previamente impregnadas, sendo 45 com doxiciclina e 45 com cloridrato de tetraciclina, e dispostas em placas de cultura contendo microrganismos aeróbios e anaeróbios. O período experimental foi de 5 semanas, com avaliações regulares a cada semana com objetivo de identificar a integridade das membranas e a capacidade de inibir o crescimento bacteriano pela presença dos halos de inibição. Resultados: Ao final do experimento constatou-se que para culturasaeróbias o período mínimo de inibição foi de 21 dias, para anaeróbiasfoi de 28 dias e os resultados foram estatisticamente superiores para a doxiciclina. Conclusão: Ambas as membranas apresentam habilidade de inibição bacteriana, confirmando a possibilidade das membranas testadas serem utilizadas como carreadores de agentes antimicrobianos, especialmente para a doxiciclina.


Objective: The membrane exposure during periodontal regenerative procedures can lead to contamination and postoperative complications. This study evaluated the ability of an absorbable membrane acting as a carrier for chemotherapeutic. Materials and Methods: Samples of absorbable bovine bone membranes, which were previously impregnated with doxycycline and tetracycline hydrochloride, were placed in culture plates containing aerobic and anaerobic microorganisms. The experimental period lasted 5 weeks, with samples analyzed weekly during this period. Results: At the end of the experiment it was found that for aerobic culturesthe minimum period of inhibition was 21 days and for anaerobic was 28 days; the results were statistically superior to doxycycline. Conclusion: Both membranes have the ability of bacterial inhibition, confirming the ability of the tested membranes been used as carriers of antimicrobial agents, especially for doxycycline.

6.
Bioorg Med Chem ; 22(12): 3115-22, 2014 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-24794748

RESUMO

The incidence of cancer grows annually worldwide and in Brazil it is the second cause of death. The search for anti-cancer drugs has then become urgent. It depends on the studies of natural and chemical synthesis products. The antitumor action of LQB-118, a pterocarpanquinone structurally related to lapachol, has been demonstrated to induce mechanisms linked to leukemia cell apoptosis. This work investigated some mechanisms of the in vitro antitumor action of LQB-118 on prostate cancer cells. LQB-118 reduced the expression of the c-Myc transcription factor, downregulated the cyclin D1 and cyclin B1 mRNA levels and upregulated the p21 cell cycle inhibitor. These effects resulted in cell cycle arrest in the S and G2/M phases and inhibition of tumor cell proliferation. LQB-118 also induced programmed cell death of the prostate cancer cells, as evidenced by internucleosomal DNA fragmentation and annexin-V positive cells. Except the cell cycle arrest in the S phase and enhanced c-Myc expression, all the mechanisms observed here for the in vitro antitumor action of LQB-118 were also found for Paclitaxel, a traditional antineoplastic drug. These findings suggest new molecular mechanisms for the LQB-118 in vitro antitumor action.


Assuntos
Proliferação de Células/efeitos dos fármacos , Ciclina D1/antagonistas & inibidores , Inibidor de Quinase Dependente de Ciclina p21/antagonistas & inibidores , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Naftoquinonas/farmacologia , Neoplasias da Próstata/patologia , Proteínas Proto-Oncogênicas c-myc/antagonistas & inibidores , Pterocarpanos/farmacologia , Apoptose/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Ciclina D1/genética , Ciclina D1/metabolismo , Inibidor de Quinase Dependente de Ciclina p21/genética , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Regulação para Baixo , Citometria de Fluxo , Humanos , Masculino , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/genética , Neoplasias da Próstata/metabolismo , Proteínas Proto-Oncogênicas c-myc/genética , Proteínas Proto-Oncogênicas c-myc/metabolismo , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Células Tumorais Cultivadas
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...