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Avaliação da taxa de metilação do DNA de leucócitos na região promotora dos genes IFNγ, Serpin B5 e Stratifin durante o período gestacional e sua relação com o metabolismo das vitaminas e metabólitos; Assessment of leukocyte DNA methylation index in the promoter region of IFNγ, Serpin B5 and Stratifin genes in women with different gestational ages and their relationship to the metabolism of vitamins and metabolites

Silva, Thaiomara Alves
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 15/10/2010 Português
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A metilação do DNA é uma alteração epigenética que atua na regulação da expressão gênica. A deficiência de vitaminas (cobalamina, B6 e folato) pode interferir na taxa de metilação. O efeito da deficiência destas vitaminas foi determinado em estudos com cultura de células e em animais. No entanto, são raros os estudos realizados com seres humanos. Os objetivos deste trabalho foram: avaliar a taxa de metilação do DNA de leucócitos na região promotora dos genes Interferon gama (IFNγ), Serpin B5 e Stratifin; verificar se existe associação entre as concentrações das vitaminas e dos metabólitos com a taxa de metilação do DNA dos 3 genes; e analisar quais são os fatores de predição para a taxa de metilação do DNA (variável dependente) considerando como variáveis independentes os valores séricos das vitaminas e metabólitos, em mulheres com idades gestacionais de 16, 28 e 36 semanas. Cento e oitenta e três mulheres foram convidadas a participar desse estudo, porém apenas 96 completaram o estudo prospectivo. Foram determinadas as concentrações séricas da cobalamina (Cbl), folato, vitamina B6, S-adenosilmetionina (SAM), S-adenosilhomocisteína (SAH), ácido metilmalônico (MMA), homocisteína total (tHcy) e folato eritrocitário. A taxa de metilação nos 3 genes foi determinada por qMSP (Quantitative Methylation Specific - Polimerase Chain Reaction). Várias mulheres estavam fazendo uso de suplementação com ácido fólico e/ou polivitamínicos. Diante deste fato foram formados 4 subgrupos: Grupo 1 (constituído por mulheres que não usaram suplementação)...

Impacto da ausência do interferon gama na plasticidade sináptica após lesão do nervo isquiático; Interferon of impact gamma in the of synaptic plasticity after sciatic nerve lesion

Sheila Cristina da Silva Victorio
Fonte: Biblioteca Digital da Unicamp Publicador: Biblioteca Digital da Unicamp
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 28/01/2011 Português
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Na medula espinal, o estabelecimento das sinapses é, provavelmente, coordenado pelos próprios neurônios. Contudo, as células da glia circunjacentes e o microambiente formado entre neurônios/glia, desempenham papel importante na modulação da excitabilidade neural, influenciando na transmissão e plasticidade sináptica. Em situações de injúria ou inflamação, há um aumento da reatividade glial e mudança do estado funcional dos neurônios, levando a uma consequente cascata de eventos visando a homeostase do tecido. Neste sentido, o IFNγ está envolvido na regulação da expressão do MHC I, o qual tem recentemente mostrado exercer um papel importante nos processos de plasticidade sináptica após axotomia. Além disso, existem evidências de que o IFNγ pode interferir na diferenciação e sobrevivência das células neurais. No entanto, pouco se sabe sobre os efeitos da ausência do IFNγ nos neurônios espinais após lesão. Portanto, o objetivo deste trabalho foi investigar os fenômenos de plasticidade sináptica e da reatividade glial em camundongos mutantes para IFNγ, a fim de analisar a dinâmica das sinapses na medula após a lesão do nervo isquiático em animais incapazes de regular a expressão de MHC I pela produção de IFNγ. Para isso...

Single nucleotide polymorphisms in the interferon gamma gene are associated with distinct types of retinochoroidal scar lesions presumably caused by Toxoplasma gondii infection

Peixe,Ricardo Guerra; Boechat,Marcela Santana Bastos; Rangel,Alba Lucinia Peixoto; Rosa,Rhônia França Gomes; Petzl-Erler,Maria Luiza; Bahia-Oliveira,Lilian MG
Fonte: Instituto Oswaldo Cruz, Ministério da Saúde Publicador: Instituto Oswaldo Cruz, Ministério da Saúde
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/02/2014 Português
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The association of single nucleotide polymorphisms (SNPs) in the interferon (IFN)-γ gene ( IFNG ) with different types of retinal scar lesions presumably caused by toxoplasmosis were investigated in a cross-sectional population-based genetic study. Ten SNPs were investigated and after Bonferroni correction, only the associations between SNPs rs2069718 and rs3181035 with retinal/retinochoroidal scar lesions type A (most severe scar lesions) and C (least severe scar lesions), respectively, remained significant. The associations of two different IFNG SNPs with two different types of retinal lesions attributable to toxoplasmosis support the hypothesis that different inflammatory mechanisms underlie the development of these lesions. The in vitro analysis of IFN-γ secretion by peripheral blood mononuclear cells stimulated with Toxoplasma gondii antigens was also investigated. The association between SNP rs2069718 and type A scar lesions revealed that differential IFN-γ levels are correlated with distinct genotypes. However, no correlation was observed with IFN-γ secretion levels and the SNP rs3181035 , which was significantly associated with type C scar lesions. Our findings strongly suggest that immunogenetic studies of individuals with congenital or postnatally acquired infection are needed to better understand the role of IFN-γ and its polymorphisms in the pathogenesis of ocular toxoplasmosis.

Interferon-γ inhibits group B Streptococcus survival within human endothelial cells

Lione,Viviane de Oliveira Freitas; Santos,Michelle Hanthequeste Bittencourt dos; Oliveira,Jessica Silva Santos de; Mattos-Guaraldi,Ana Luiza; Nagao,Prescilla Emy
Fonte: Instituto Oswaldo Cruz, Ministério da Saúde Publicador: Instituto Oswaldo Cruz, Ministério da Saúde
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/11/2014 Português
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46.75%
Endothelial dysfunction is a major component of the pathophysiology of septicaemic group B Streptococcus (GBS) infections. Although cytokines have been shown to activate human umbilical vein endothelial cells (HUVECs), the capacity of interferon (IFN)-γ to enhance the microbicidal activity of HUVECs against GBS has not been studied. We report that the viability of intracellular bacteria was reduced in HUVECs activated by IFN-γ. Enhanced fusion of lysosomes with bacteria-containing vacuoles was observed by acid phosphatase and the colocalisation of Rab-5, Rab-7 and lysosomal-associated membrane protein-1 with GBS in IFN-γ-activated HUVECs. IFN-γ resulted in an enhancement of the phagosome maturation process in HUVECs, improving the capacity to control the intracellular survival of GBS.

Mycobacterium tuberculosis epitope-specific interferon-g production in healthy Brazilians reactive and non-reactive to tuberculin skin test

Silva,Bosco Christiano Maciel da; Grassi,Maria Fernanda Rios; Coutinho,Raimundo; Mascarenhas,Rita Elizabeth Moreira; Olavarria,Viviana Nilla; Coutinho-Borgo,Adriana; Kalil,Jorge; Cunha Neto,Edecio; Fonseca,Simone Gonçalves
Fonte: Instituto Oswaldo Cruz, Ministério da Saúde Publicador: Instituto Oswaldo Cruz, Ministério da Saúde
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/12/2014 Português
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36.75%
The interferon (IFN)-γ response to peptides can be a useful diagnostic marker of Mycobacterium tuberculosis (MTB) latent infection. We identified promiscuous and potentially protective CD4+ T-cell epitopes from the most conserved regions of MTB antigenic proteins by scanning the MTB antigenic proteins GroEL2, phosphate-binding protein 1 precursor and 19 kDa antigen with the TEPITOPE algorithm. Seven peptide sequences predicted to bind to multiple human leukocyte antigen (HLA)-DR molecules were synthesised and tested with IFN-γ enzyme-linked immunospot (ELISPOT) assays using peripheral blood mononuclear cells (PBMCs) from 16 Mantoux tuberculin skin test (TST)-positive and 16 TST-negative healthy donors. Eighty-eight percent of TST-positive donors responded to at least one of the peptides, compared to 25% of TST-negative donors. Each individual peptide induced IFN-γ production by PBMCs from at least 31% of the TST-positive donors. The magnitude of the response against all peptides was 182 ± 230 x 106 IFN-γ spot forming cells (SFC) among TST-positive donors and 36 ± 62 x 106 SFC among TST-negative donors (p = 0.007). The response to GroEL2 (463-477) was only observed in the TST-positive group. This combination of novel MTB CD4 T-cell epitopes should be tested in a larger cohort of individuals with latent tuberculosis (TB) to evaluate its potential to diagnose latent TB and it may be included in ELISPOT-based IFN-γ assays to identify individuals with this condition.

Lactobacillus delbrueckii UFV-H2b20 induces type 1 cytokine production by mouse cells in vitro and in vivo

Neumann,E.; Ramos,M.G.; Santos,L.M.; Rodrigues,A.C.P.; Vieira,E.C.; Afonso,L.C.C.; Nicoli,J.R.; Vieira,L.Q.
Fonte: Associação Brasileira de Divulgação Científica Publicador: Associação Brasileira de Divulgação Científica
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/04/2009 Português
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36.65%
Lactobacillus delbrueckii UFV-H2b20 has been shown to increase clearance of bacteria injected into the blood of germ-free mice. Moreover, it induces the production of type 1 cytokines by human peripheral mononuclear cells. The objective of the present study was to investigate the production of inflammatory cytokines [interleukin-12 (IL-12 p40), tumor necrosis factor-α (TNF-α), and interferon-γ (IFN-γ)] triggered in vitro by live, heat-killed or lysozyme-treated L. delbrueckii UFV-H2b20 and in vivo by a live preparation. Germ-free, L. delbrueckii-monoassociated and lipopolysaccharide (LPS)-resistant C3H/HeJ mice were used as experimental models. UFV-H2b20 induced the production of IL-12 p40 and TNF-α by peritoneal cells and IFN-γ by spleen cells from germ-free or monoassociated Swiss/NIH mice and LPS-hyporesponsive mice (around 40 ng/mL for IL-12 p40, 200 pg/mL for TNF-α and 10 ng/mL for IFN-γ). Heat treatment of L. delbrueckii did not affect the production of these cytokines. Lysozyme treatment decreased IL-12 p40 production by peritoneal cells from C3H/HeJ mice, but did not affect TNF-α production by these cells or IFN-γ production by spleen cells from the same mouse strain. TNF-α production by peritoneal cells from Swiss/NIH L. delbrueckii-monoassociated mice was inhibited by lysozyme treatment. When testing IL-12 p40 and IFN-γ levels in sera from germ-free or monoassociated Swiss/NIH mice systemically challenged with Escherichia coli we observed that IL-12 p40 was produced at marginally higher levels by monoassociated mice than by germ-free mice (40 vs 60 ng/mL)...

Interleukin-10-dependent down-regulation of interferon-gamma response to Leishmania by Mycobacterium leprae antigens during the clinical course of a coinfection

Azeredo-Coutinho,R.B.G.; Matos,D.C.S.; Nery,J.A.C.; Valete-Rosalino,C.M.; Mendonça,S.C.F.
Fonte: Associação Brasileira de Divulgação Científica Publicador: Associação Brasileira de Divulgação Científica
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/07/2012 Português
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We have described a case of a patient with an intriguing association of mucocutaneous leishmaniasis with lepromatous leprosy, two opposite polar forms of these spectral diseases. In the present follow-up study, we investigated the effect of the addition of Mycobacterium leprae antigens on interferon-gamma (IFN-γ) production in Leishmania antigen-stimulated cultures of peripheral blood mononuclear cells (PBMC) from this patient. For this purpose, PBMC cultures were stimulated with crude L. braziliensis and/or M. leprae whole-cell antigen extracts or with concanavalin A. In some experiments, neutralizing anti-human interleukin (IL)-10 antibodies were added to the cultures. IFN-γ and IL-10 levels in culture supernatants were measured by ELISA. During active leprosy, M. leprae antigens induced 72.3% suppression of the IFN-γ response to L. braziliensis antigen, and this suppression was abolished by IL-10 neutralization. Interestingly, the suppressive effect of M. leprae antigen was lost after the cure of leprosy and the disappearance of this effect was accompanied by exacerbation of mucosal leishmaniasis. Considered together, these results provide evidence that the concomitant lepromatous leprosy induced an IL-10-mediated regulatory response that controlled the immunopathology of mucosal leishmaniasis...

The increased but non-predominant expression of Th17- and Th1-specific cytokines in Hashimoto’s thyroiditis but not in Graves’ disease

Qin,Qiu; Liu,Ping; Liu,Lin; Wang,Rong; Yan,Ni; Yang,Jing; Wang,Xuan; Pandey,Madhu; Zhang,Jin-an
Fonte: Associação Brasileira de Divulgação Científica Publicador: Associação Brasileira de Divulgação Científica
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/12/2012 Português
Relevância na Pesquisa
36.62%
Hashimoto’s thyroiditis (HT) is considered to be mediated mainly by Th1 cells, but it is not known whether Graves’ disease (GD) is associated with Th1 or Th2 predominance. Th17 cells, a novel subset of Th cells, play a crucial role in the pathogenesis of various autoimmune disorders. In the present study, the expression of IL-17A and IFN-γ was investigated in patients with HT or GD. mRNA expression of IL-17A and IFN-γ in peripheral blood mononuclear cells (PBMC) from 43 patients with autoimmune thyroid disease (AITD) and in thyroid tissues from 40 AITD patients were measured by real-time qRT-PCR. The protein expression of IL-17A and IL-23p19 was examined by immunohistochemistry in thyroid tissues from 28 AITD patients. The mRNA levels of IL-17A and IFN-γ were higher in both PBMC and thyroid tissues of HT patients than in controls (mRNA levels are reported as the cytokine/β-actin ratio: IL-17 = 13.58- and 2.88-fold change and IFN-γ = 16.54- and 2.74-fold change, respectively, P < 0.05). Also, the mRNA levels of IL-17A and IFN-γ did not differ significantly in GD patients (P > 0.05). The high protein expression of IL-17A (IOD = 15.17 ± 4.8) and IL-23p19 (IOD = 16.84 ± 7.87) in HT was confirmed by immunohistochemistry (P < 0.05). The similar high levels of IL-17A and IFN-γ suggest a mixed response of Th17 and Th1 in HT...

Pesquisa de interferon gama em tecido periodontal de ratos submetidos à movimentação dentária induzida

Silveira,Daniel Mascarenhas da; Franco,Fernanda Catharino Menezes; Nascimento,Ivana Lúcia de Oliveira; Salomão,Milene de Freitas Lima; Araujo,Telma Martins de
Fonte: Dental Press Editora Publicador: Dental Press Editora
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/04/2009 Português
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INTRODUÇÃO: durante o tratamento ortodôntico, um processo inflamatório é induzido, desencadeando uma série de eventos bioquímicos que resultam na movimentação dentária. Estímulos como a hipóxia e a deformação mecânica são os principais fatores responsáveis pela quebra da homeostasia celular, resultando em estresse e liberação de diversos mediadores importantes para o movimento do dente. Para que a remodelação óssea ocorra durante o tratamento ortodôntico, fatores reguladores,como subprodutos do ácido araquidônico e citocinas,são liberados.Ao interferon gama (INF-γ , uma citocina principal liberada após a indução da resposta imune adaptativa, é atribuída a função de atrair os macrófagos, que auxiliam na remoção de restos celulares e promovem a cicatrização e reorganização das áreas com inflamação. OBJETIVO: visto que alguns aspectos biológicos que permeiam a movimentação dentária ainda não estão totalmente esclarecidos, procurou-se, neste trabalho, verificar a expressão do INF-γ por células do periodonto de ratos submetidos à movimentação ortodôntica. MÉTODOS: a amostra foi constituída por nove ratos, cujos primeiros molares superiores direitos foram movimentados com uma força de 0...

Alergia à proteína do leite de vaca em crianças: avaliação clínica e concentrações séricas de interferon- γ e interleucina- 4

das Graças Moura Lins, Maria; Eugenia Farias Almeida Motta, Maria (Orientador)
Fonte: Universidade Federal de Pernambuco Publicador: Universidade Federal de Pernambuco
Tipo: Outros
Português
Relevância na Pesquisa
67.03%
Introdução O diagnóstico da alergia à proteína do leite de vaca através de sintomas é bastante falível, representa mais ou menos a metade dos casos suspeitos. A produção e as concentrações do Interferon-γ e Interleucina-4 têm sido estudadas como sinalizadores das reações inflamatórias na alergia à proteína do leite de vaca em atividade e na tolerância oral com ações contrarreguladoras. Objetivos. 1- Determinar a frequência de alergia em crianças com sintomas de intolerância ao leite de vaca. 2 - Determinar as concentrações séricas do interferon-gama e da interleucina-4 em crianças com sintomas suspeitos de alergia à proteína do leite de vaca. Método. Foram estudada 65 crianças (2-84 meses), com intolerância ao leite de vaca, foram estudadas. Informações da história clínica, níveis e IgE total e específicas, Interferon-γ, Interleucina-4 e teste do desencadeamento alimentar oral, realizado para determinação das crianças com e sem alergia à proteína do leite de vaca foram registrados em formulário estruturado.Os sintomas entre os dois grupos foram analisados. As idades e citocinas foram sumarizadas como medianas e comparadas pelo teste de Mann-Whitney. As diferenças entre as variáveis categóricas foram determinadas pelo teste qui-quadrado. Os testes estatísticos foram considerados significantes com p< 0...

Expressão imuno-histoquímica das proteínas IFN-γ e TGF-β1 em cistos radiculares e cistos dentígeros

Rocha Neto, Pedro Carlos da
Fonte: Universidade Federal do Rio Grande do Norte; BR; UFRN; Programa de Pós-Graduação em Patologia Oral; Odontologia Publicador: Universidade Federal do Rio Grande do Norte; BR; UFRN; Programa de Pós-Graduação em Patologia Oral; Odontologia
Tipo: Dissertação Formato: application/pdf
Português
Relevância na Pesquisa
36.88%
Odontogenic cysts are pathologic cavities covered by odontogenic epithelium and filled by liquid, desquamated cells or other materials. The intraosseous lesions, such as radicular cyst and dentigerous cyst, present a potential of expansion capable of promoting the destruction of the surrounding osseous tissue. The mechanisms related to this process of expansion are the proliferation of cystic epithelium, the increase of the osmolarity of the cystic fluid and the synthesis of reabsorption factors such as IFN-γ and TGF-β1. The aim of this study was to evaluate and compare the immunohistochemical expression of IFN-γ and TGF-β1 between radicular cysts and dentigerous cysts in order to understand the role and behavior of these proteins in the expansion of these cysts. We selected 20 cases of radicular cyst and 20 cases of dentigerous cyst chosen from the files of UFRN s Laboratory of Oral Pathology. After analyzing the clinical data, the cases underwent the routine staining technique (HE) and immunohistochemistry for the appearance of IFN-γ and TGF-β1 in the epithelium and capsule of these cysts. The statistical analysis using the Mann-Whitney test revealed no statistically significant difference in immunoexpression of IFN-γ between the epithelium (p = 0.565) and capsules (p = 0.414) of radicular cysts and dentigerous cysts. Moreover...

A STUDY OF HOST-CHLAMYDIAL INTERACTIONS MEDIATED BY INTERFERON-GAMMA AND NITRIC OXIDE

Rajaram, Krithika
Fonte: [Bloomington, Ind.] : Indiana University Publicador: [Bloomington, Ind.] : Indiana University
Tipo: Doctoral Dissertation
Português
Relevância na Pesquisa
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Thesis (Ph.D.) - Indiana University, Biology, 2015; The host response towards chlamydial infection mobilizes elements of both innate and adaptive immunity, culminating in the production of the Th1 cytokine interferon-gamma (IFN-γ). IFN-γ induces a variety of anti-chlamydial programs, many of which are unique to either humans or mice. Consequently, the human pathogen Chlamydia trachomatis and its near-identical murine relative C. muridarum have evolved to survive and cause disease in their respective hosts. Understanding the mechanisms that contribute to chlamydial niche specificity will facilitate the creation of improved mouse models for the study of human chlamydial disease. To this end, we examined a small chlamydial genomic region of extreme divergence called the Plasticity Zone (PZ) in C. muridarum for its alleged roles in host specificity and virulence. Using a newly adapted reverse genetic technique, we determined that much of the PZ is in fact dispensable in the murine genital tract. We concomitantly embarked on a screen for C. muridarum mutants that were no longer resistant to IFN-γ and uncovered a gain-of-function mutation in an orf outside the PZ that led to dramatic attenuation in mice. IFN-γ is secreted by multiple cell types including macrophages...

Leishmania spp. parasite isolation through inoculation of patient biopsy macerates in interferon gamma knockout mice; Leishmania spp.: isolamento de parasitos pela inoculação de macerados de biopsias de pacientes em camundongos deficientes em interferon gama

OLIVEIRA, Milton Adriano Pelli de; PIRES, Alause da Silva; BASTOS, Rosidete Pereira de; LIMA, Glória Maria Collet de Araujo; PINTO, Sebastião Alves; PEREIRA, Ledice Inácia de Araujo; PEREIRA, Ana Joaquina Cohen Serique; ABRAHAMSOHN, Ises de Almeida; DO
Fonte: Instituto de Medicina Tropical Publicador: Instituto de Medicina Tropical
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
36.91%
Isolation of Leishmania parasite and species identification are important for confirmation and to help define the epidemiology of the leishmaniasis. Mice are often used to isolate pathogens, but the most common mouse strains are resistant to infection with parasites from the Leishmania (Viannia) subgenus. In this study we tested the inoculation of interferon gamma knockout (IFNγ KO) mice with biopsy macerates from Leishmania-infected patients to increase the possibility of isolating parasites. Biopsies from twenty five patients with clinical signs of leishmaniasis were taken and tested for the presence of parasites. Immunohistochemical assay (IHC) and conventional histopathology detected the parasite in 88% and 83% of the patients, respectively. Leishmania sp. were isolated in biopsy macerates from 52% of the patients by culture in Grace's insect medium, but 13% of isolates were lost due to contamination. Inoculation of macerates in IFNγ KO mice provides isolation of parasites in 31.8% of the biopsies. Most isolates belong to L. (Viannia) subgenus, as confirmed by PCR, except one that belongs to L. (Leishmania) subgenus. Our preliminary results support the use of IFNγ KO mice to improve the possibility to isolate New World Leishmania species.; O isolamento e a identificação da espécie de parasito do gênero Leishmania são importantes para a confirmação e auxiliam na epidemiologia da leishmaniose. Os camundongos são freqüentemente utilizados para isolar patógenos...

Leishmania spp. parasite isolation through inoculation of patient biopsy macerates in interferon gamma knockout mice

Oliveira,Milton Adriano Pelli de; Pires,Alause da Silva; Bastos,Rosidete Pereira de; Lima,Glória Maria Collet de Araujo; Pinto,Sebastião Alves; Pereira,Ledice Inácia de Araujo; Pereira,Ana Joaquina Cohen Serique; Abrahamsohn,Ises de Almeida; Dorta,Miri
Fonte: Instituto de Medicina Tropical Publicador: Instituto de Medicina Tropical
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/04/2010 Português
Relevância na Pesquisa
36.66%
Isolation of Leishmania parasite and species identification are important for confirmation and to help define the epidemiology of the leishmaniasis. Mice are often used to isolate pathogens, but the most common mouse strains are resistant to infection with parasites from the Leishmania (Viannia) subgenus. In this study we tested the inoculation of interferon gamma knockout (IFNγ KO) mice with biopsy macerates from Leishmania-infected patients to increase the possibility of isolating parasites. Biopsies from twenty five patients with clinical signs of leishmaniasis were taken and tested for the presence of parasites. Immunohistochemical assay (IHC) and conventional histopathology detected the parasite in 88% and 83% of the patients, respectively. Leishmania sp. were isolated in biopsy macerates from 52% of the patients by culture in Grace's insect medium, but 13% of isolates were lost due to contamination. Inoculation of macerates in IFNγ KO mice provides isolation of parasites in 31.8% of the biopsies. Most isolates belong to L. (Viannia) subgenus, as confirmed by PCR, except one that belongs to L. (Leishmania) subgenus. Our preliminary results support the use of IFNγ KO mice to improve the possibility to isolate New World Leishmania species.

Genetic polymorphisms in vitamin D receptor, vitamin D-binding protein, Toll-like receptor 2, nitric oxide synthase 2, and interferon-γ genes and its association with susceptibility to tuberculosis

Leandro,A.C.C.S.; Rocha,M.A.; Cardoso,C.S.A.; Bonecini-Almeida,M.G.
Fonte: Associação Brasileira de Divulgação Científica Publicador: Associação Brasileira de Divulgação Científica
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/04/2009 Português
Relevância na Pesquisa
56.66%
Mycobacterium tuberculosis kills more people than any other single pathogen, with an estimated one-third of the world's population being infected. Among those infected, only 10% will develop the disease. There are several demonstrations that susceptibility to tuberculosis is linked to host genetic factors in twins, family and associated-based case control studies. In the past years, there has been dramatic improvement in our understanding of the role of innate and adaptive immunity in the human host defense to tuberculosis. To date, attention has been paid to the role of genetic host and parasitic factors in tuberculosis pathogenesis mainly regarding innate and adaptive immune responses and their complex interactions. Many studies have focused on the candidate genes for tuberculosis susceptibility ranging from those expressed in several cells from the innate or adaptive immune system such as Toll-like receptors, cytokines (TNF-α, TGF-β, IFN-γ, IL-1b, IL-1RA, IL-12, IL-10), nitric oxide synthase and vitamin D, both nuclear receptors and their carrier, the vitamin D-binding protein (VDBP). The identification of possible genes that can promote resistance or susceptibility to tuberculosis could be the first step to understanding disease pathogenesis and can help to identify new tools for treatment and vaccine development. Thus...

Leishmania spp.: isolamento de parasitos pela inoculação de macerados de biopsias de pacientes em camundongos deficientes em interferon gama; Leishmania spp. parasite isolation through inoculation of patient biopsy macerates in interferon gamma knockout mice

Oliveira, Milton Adriano Pelli de; Pires, Alause da Silva; Bastos, Rosidete Pereira de; Lima, Glória Maria Collet de Araujo; Pinto, Sebastião Alves; Pereira, Ledice Inácia de Araujo; Pereira, Ana Joaquina Cohen Serique; Abrahamsohn, Ises de Almeida; Do
Fonte: Universidade de São Paulo. Instituto de Medicina Tropical de São Paulo Publicador: Universidade de São Paulo. Instituto de Medicina Tropical de São Paulo
Tipo: info:eu-repo/semantics/article; info:eu-repo/semantics/publishedVersion; ; ; ; ; Formato: application/pdf
Publicado em 01/04/2010 Português
Relevância na Pesquisa
36.91%
O isolamento e a identificação da espécie de parasito do gênero Leishmania são importantes para a confirmação e auxiliam na epidemiologia da leishmaniose. Os camundongos são freqüentemente utilizados para isolar patógenos, porém, as linhagens mais comuns de camundongos são resistentes à infecção por parasitos do subgênero Leishmania (Viannia). Neste estudo, avaliamos a inoculação de macerados de biópsias de pacientes infectados em camundongos deficientes do gene do interferon gama (IFNγ KO) como um método para aumentar a possibilidade de isolar Leishmania spp. Biópsias de 25 pacientes infectados com Leishmania sp. foram avaliadas para a presença de parasitos pelos métodos de imunohistoquímica (IHC) e histopatologia convencional. Os parasitos foram observados, respectivamente, em 88% e 83% das biópsias. Leishmania sp. foi isolada de macerados de biópsia de 52% dos pacientes infectados, quando cultivados em meio Grace, porém, 13% destes isolados foram perdidos devido a contaminações. Inoculação dos macerados em camundongos IFNγ KO proporcionou o isolamento de parasitos oriundos de 31,8% dos pacientes. A maioria dos isolados pertence ao subgênero L. (Viannia), exceto um que pertence ao subgênero L. (Leishmania)...

Interferón gamma recombinante como alternativa terapéutica en niños con artritis idiopática juvenil

Coto Hermosilla,Cecilia; García García,Idrian; Díaz Rojo,Gisou; Bello Rivero,Iraldo; Bermudez Badell,Cimara; Valera Puente,Gloria; Cantero Oceguera,Dolores; Hernández González,Víctor; Méndez Méndez,Melba; Gómez Conde,Santa; Nodarse Cuní,Hugo; L
Fonte: Revista Cubana de Pediatría Publicador: Revista Cubana de Pediatría
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/03/2010 Português
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36.66%
INTRODUCCIÓN. La artritis idiopática juvenil (AIJ) es una enfermedad del colágeno caracterizada por sinovitis crónica y síntomas extraarticulares, de inicio antes de los 16 años de edad. El interferón gamma (INFγ) mostró eficacia en un ensayo anterior con pacientes resistentes o intolerantes a las otras terapias disponibles, por lo que se decidió evaluar su eficacia y seguridad como medicamento modificador de la evolución de esta enfermedad. MÉTODOS. Se realizó un ensayo clínico abierto, no controlado, en el que se administró INFγ por vía intramuscular en dosis de 50 000 UI/kg (hasta 1 x 10(6) UI) durante 2 años. En el ensayo se incluyeron 20 pacientes con AIJ: 5 tenían la forma pauciarticular; 9, la poliarticular y 6, la sistémica. RESULTADOS. Al final del tratamiento, 13 pacientes (65 %) se evaluaron como respondedores. El número de articulaciones afectadas, los síntomas sistémicos y los valores de eritrosedimentación y del cuestionario de calidad se redujeron significativamente. Igualmente disminuyó el número de pacientes que continuó consumiendo esteroides, así como la dosis de éstos. El tratamiento fue bien tolerado, excepto en 2 pacientes. CONCLUSIONES. El INFγ disminuye la expresión de la quimiocina CCR-4 en los niños...

Comparison of interferon-γ release assay and tuberculin test for screening in healthcare workers

Costa,José Torres; Silva,Rui; Sá,Raul; Cardoso,Maria João; Ribeiro,Carla; Nienhaus,Albert
Fonte: Sociedade Portuguesa de Pneumologia Publicador: Sociedade Portuguesa de Pneumologia
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/04/2010 Português
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46.29%
Healthcare workers (HCWs) have an increased risk of tuberculosis (TB). Screening for latent tuberculosis infection and active TB is therefore essential in infection control programs. Tuberculin skin test (TST) and Interferon-ƒÁ Release Assay (IGRA) were used simultaneously in 1686 HCWs between May 2007 and April 2009. A chest X-ray was performed in order to exclude active TB when TST was .10mm or IGRA was positive and in HCWs with TB contact or symptoms. IGRA was positive in 33.1% and TST was >10mm in 78.3% of the HCWs. The proportionof positive IGRA results increased with the TST diameter. In those with a TST >15mm, 49.2% were IGRA positive. TST was more than twice as often positive than the IGRA. Therefore, TST+/IGRA- results were more often observed than concordant negative or positive results. In none of the HCWs with a TST+/IGRA- result active TB was diagnosed during the study period. Repeated BCG vaccination increased the number of TST+/IGRA- discordance. The smaller the interval after BCG vaccination, the higher was the TST+/IGRA- discordance. In the screened HCWs population, active TB was diagnosed in 9. At the time of diagnosis TST and IGRA were positive in all active TB cases. The study period covers 24 months, therefore the average annual incidence rate was 268/100 000. TB burden in HCWs in Portugal is high. Considering the limitations that TST and IGRA present...

Role of interleukin-6, gamma interferon and adenosine deaminase markers in management of pleural effusion patients

Marie,MAM; John,J; Krishnappa,L Gowda; Gopalkrishnan,S; Bindurani,SR; CS,P
Fonte: West Indian Medical Journal Publicador: West Indian Medical Journal
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/12/2013 Português
Relevância na Pesquisa
36.66%
OBJECTIVE: Pleural effusion is a common diagnostic and clinical problem. Neoplasms and tuberculosis are the most frequent diagnostic causes of such effusions. Conventional laboratory methods for diagnosis of such effusion are inefficient because tubercle bacilli are rarely seen in direct examinations of pleural fluid. The present study evaluates interleukin-6 (IL-6), gamma interferon (IFN-γ) and adenosine deaminase (ADA) as diagnostic tools in pleural effusion. METHODS: Interleukin-6, IFN-γ and ADA were measured in pleural fluid from the patients, with exudative pleural effusion from tuberculous, malignant and postpneumonic origin and transudative pleural effusion ofsystemic origin in order to evaluate the diagnostic utility ofthese. RESULTS: The three markers were detectable in all effusions with significantly high levels in exudative as compared to transudative effusions. There was a statically significant difference noticed in tuberculous as compared to malignant andpostpneumonic origin and transudative pleural effusion. CONCLUSION: We concluded that IL-6, IFN-γ and ADA levels in pleural effusion are sensitive parameters to differentiate an exudate from a transudate and they can also differentiate exudates of different aetiology. Finally...

Efecto de la maca roja (Lepidium meyenii) sobre los niveles de IFN-γ en ratas ovariectomizadas

Leiva-Revilla,Johanna; Guerra-Castañon,Félix; Olcese-Mori,Paola; Lozada,Iván; Rubio,Julio; Gonzales,Carla; Gonzales,Gustavo F.
Fonte: Instituto Nacional de Salud Publicador: Instituto Nacional de Salud
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/12/2014 Português
Relevância na Pesquisa
36.75%
Objetivos. Comparar el efecto de diferentes dosis de maca roja sobre los niveles de interferón gamma (IFN-γ) en ratas ovariectomizadas (OVX). Materiales y métodos. Ratas hembras adultas fueron divididas al azar en los siguientes seis grupos: Grupo 1: ratas pesudo-ovariectomizadas (PO); Grupo 2: ratas OVX; Grupo 3: ratas OVX tratadas con 4 ug/kg de estradiol, y Grupo 4, 5 y 6: ratas OVX tratadas con extractos de maca con 2,15, 4,3 y 8,6 mg polifenoles/kilogramo de peso corporal, respectivamente. Resultados. Las ratas OVX mostraron niveles bajos de IFN-γ en comparación con las ratas PO. El estradiol y la maca roja revirtieron el efecto de la ovariectomía sobre los niveles de IFN-γ. La maca roja presenta un incremento dosis-respuesta de los niveles de IFN-γ (r=0,57, p<0,05). Conclusiones. La administración de la maca roja incrementa los niveles de IFN-γ en ratas ovariectomizadas.