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2.
PLoS One ; 15(11): e0241487, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33206689

RESUMO

ABH antigens are histo-antigens, but were first described on the surface of human erythrocytes. They are found in those cells only in great apes and humans, while in more primitive animals they are found in tissues and body fluids. ABH antigens are mainly distributed in tissues that are in contact with the external environment and may serve as ligands for pathogens in tissues or block their connection. Description of the distribution of these molecules in non-human primate tissues is restricted to a few tissues and species. This paper describes the expression of human A, B and H type antigens in different organs from four species of New World Primates, obtained from the Centro Nacional de Primatas, as well as comparing that expression with what has been described for humans. In this study, although the tissue description of the antigens is similar to the genetic model for humans, some differences in expression between some organs from those species and those of humans were found. The differences occurred mainly in endodermal organs that have secretory functions and are probably under the control of the human-type FUT-2 enzyme. In the mesodermal-origin organs there was a reduction or absence of A and B antigen marking, particularly in the H precursor substance, indicating that those organs are under the control of the human-type FUT-1 enzyme. These findings have demonstrated that there is similar ABH antigen reactivity in tissue distribution between the species, although there are some species-specific cases.


Assuntos
Sistema ABO de Grupos Sanguíneos/metabolismo , Antígenos/metabolismo , Especificidade de Órgãos , Animais , Aotidae , Callithrix , Platirrinos , Saimiri , Sapajus apella , Especificidade da Espécie
3.
Neurotoxicology ; 65: 60-67, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29428869

RESUMO

BACKGROUND: Mercury exposure in the Brazilian Amazon region has been an important concern since the 1980s, when gold mining activities contaminated many Amazonian river basins and the fish therein. Mercury exposure in humans can lead to changes in neural function. The visual system has been used as a functional indicator of methylmercury (organic) and mercury vapour (inorganic) toxicity. Children are particularly vulnerable to this metal exposure. OBJECTIVE: To compare the color vision of children from riverine communities of mercury-exposed (Tapajós basin) and non-exposed Amazonian rivers (Tocantins basin). METHODS: The study sample was 176 children, aged 7-14 years old. Children from two locations in the mercury-exposed Tapajós river basin, Barreiras (n = 71) and São Luiz do Tapajos (n = 41), were compared to children from Limoeiro do Ajuru (n = 64), a non-exposed area in the Tocantins river basin. No caregiver reported that any children had contact with mercury vapour during their lifetime, and probably most of the mercury in their bodies was obtained by fish consumption. Because of this, we decided to evaluate the mercury exposure by total mercury levels in hair samples, a good marker for organic mercury, and not in the urine, a marker for inorganic mercury. Color vision was assessed by the Lanthony Desaturated D-15 test. We used the Vingrys and King-Smith method (1988) to quantify the hue ordering test. The primary visual outcomes from this analysis were C-index (magnitude of the hue ordering error) and angle of the hue ordering. RESULTS: The Tapajós children had a higher mean hair mercury level (mean: 4.5 µg/g; range: 0.26-22.38 µg/g) than that of Tocantins children (mean: 0.49 µg/g; range: 0.03-1.91 µg/g) (p < 0.05). Mean difference was approximately 4.01 µg/g with a 95% confidence interval of 2.79-5.23. The results of the Lanthony D-15d test showed no significant difference between the C-index mean values of the Tapajós and Tocantins groups (p > 0.05). There was a weak linear correlation in the average C-index obtained from both eyes and the total mercury concentration. Multiple logistic regression analysis indicated that the location of the community and the age had a greater influence on the visual outcomes than the sex of the children and within-locale variation in mercury concentration. CONCLUSION: Our results suggest a difference in one aspect of vision, that is, color vision, between children living in two different river basins in the Brazilian Amazon. The association may be related to Hg exposure but also appeared related to the location of the community and age.


Assuntos
Visão de Cores/efeitos dos fármacos , Cabelo/química , Mercúrio/análise , Mercúrio/toxicidade , Envelhecimento/fisiologia , Brasil , Criança , Testes de Percepção de Cores , Visão de Cores/fisiologia , Estudos Transversais , Feminino , Geografia Médica/estatística & dados numéricos , Humanos , Masculino , Poluentes Químicos da Água/análise
4.
Mem. Inst. Oswaldo Cruz ; 106(8): 936-941, Dec. 2011. ilus, tab
Artigo em Inglês | LILACS | ID: lil-610967

RESUMO

The histo-blood group ABH antigens were first described in humans. These antigens are only present on erythrocytes from great apes and humans, while in more primitive animals they are found in tissues and body fluids. The ABH antigens are mainly distributed in tissues exposed to the external environment and potentially serve as ligands for pathogens or inhibitors of tissue connections. The objective of this paper was two-fold: (i) to determine the presence of Helicobacter sp. in the gastric mucosa of 16 captive and 24 free-living New World monkeys and (ii) to evaluate the presence of histopathological alterations related to bacterial infection and the associated expression of ABH antigens in the tissue. Stomach tissues from 13 species of monkey were assessed using haematoxylin-eosin and modified Gram staining (Hucker) methods. An immunohistochemical analysis of the tissue revealed the presence of infectious bacteria that were characteristic of the genus Helicobacter sp. The results demonstrate that various species of monkey might be naturally infected with the Helicobacter sp. and that there is an increased susceptibility to infection. This study serves as a comparative analysis of infection between human and non-human primates and indicates the presence of a new species of Helicobacter.


Assuntos
Animais , Sistema ABO de Grupos Sanguíneos/imunologia , Mucosa Gástrica/microbiologia , Infecções por Helicobacter/veterinária , Platirrinos/microbiologia , Sistema ABO de Grupos Sanguíneos/análise , Biomarcadores/análise , Mucosa Gástrica/imunologia , Infecções por Helicobacter/diagnóstico , Infecções por Helicobacter/imunologia , Infecções por Helicobacter/microbiologia , Helicobacter/classificação , Helicobacter/imunologia , Imuno-Histoquímica
5.
Mem Inst Oswaldo Cruz ; 106(8): 936-41, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22241114

RESUMO

The histo-blood group ABH antigens were first described in humans. These antigens are only present on erythrocytes from great apes and humans, while in more primitive animals they are found in tissues and body fluids. The ABH antigens are mainly distributed in tissues exposed to the external environment and potentially serve as ligands for pathogens or inhibitors of tissue connections. The objective of this paper was two-fold: (i) to determine the presence of Helicobacter sp. in the gastric mucosa of 16 captive and 24 free-living New World monkeys and (ii) to evaluate the presence of histopathological alterations related to bacterial infection and the associated expression of ABH antigens in the tissue. Stomach tissues from 13 species of monkey were assessed using haematoxylin-eosin and modified Gram staining (Hucker) methods. An immunohistochemical analysis of the tissue revealed the presence of infectious bacteria that were characteristic of the genus Helicobacter sp. The results demonstrate that various species of monkey might be naturally infected with the Helicobacter sp. and that there is an increased susceptibility to infection. This study serves as a comparative analysis of infection between human and non-human primates and indicates the presence of a new species of Helicobacter.


Assuntos
Sistema ABO de Grupos Sanguíneos/imunologia , Mucosa Gástrica/microbiologia , Infecções por Helicobacter/veterinária , Platirrinos/microbiologia , Sistema ABO de Grupos Sanguíneos/análise , Animais , Biomarcadores/análise , Mucosa Gástrica/imunologia , Helicobacter/classificação , Helicobacter/imunologia , Infecções por Helicobacter/diagnóstico , Infecções por Helicobacter/imunologia , Infecções por Helicobacter/microbiologia , Imuno-Histoquímica
6.
Arq. gastroenterol ; 39(4): 222-232, out.-dez. 2002. ilus, tab, graf
Artigo em Português | LILACS | ID: lil-341826

RESUMO

RACIONAL: A aderência do Helicobacter pylori à mucosa gástrica humana é pré-requisito para sua colonizaçäo e o desenvolvimento da gastrite crônica. Os antígenos de grupos sangüíneos, presentes no muco gástrico, säo descritos como prováveis receptores da bactéria neste epitélio. A expressäo alterada destes antígenos está associada ao desenvolvimento do câncer gástrico. OBJETIVOS: Verificar a ocorrência do Helicobacter pylori e a distribuiçäo da expressäo dos antígenos ABH e Lewis correlacionada com as alteraçöes histopatológicas de pacientes com gastrite crônica. PACIENTES E MÉTODOS: Analisaram-se 63 amostras de sangue, saliva e biopsias gástricas de pacientes com gastrite crônica através das técnicas dot-blot-ELISA, imunoperoxidase indireta e coloraçöes do Gram modificado e hematoxilina-eosina. RESULTADOS: Näo foram encontradas associaçöes significativas entre a presença da bactéria e os fenótipos de grupos sangüíneos ABH, Lewis e Secretor. Na maioria dos pacientes, a expressäo dos antígenos ABH e Lewis, estava restrita principalmente ao epitélio foveolar da mucosa gástrica, concordando com a expressäo ao nível salivar. A expressäo inapropriada desses antígenos ocorria sempre na infecçäo pelo Helicobacter pylori e/ou alteraçöes pré-neoplásicas da mucosa gástrica. Em áreas com metaplasia intestinal foi observada a reduçäo da reatividade para os antígenos H e Le b, e principalmente o aumento de Leª. CONCLUSÄO: Alteraçöes no padräo de glicosilaçäo destes antígenos refletem diferentes estágios de diferenciaçäo celular e säo marcadores potenciais na avaliaçäo diagnóstica e prognóstica das patologias gástricas


Assuntos
Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Sistema ABO de Grupos Sanguíneos , Mucosa Gástrica , Gastrite Atrófica , Infecções por Helicobacter , Helicobacter pylori , Antígenos do Grupo Sanguíneo de Lewis , Neoplasias Gástricas , Biomarcadores , Mucosa Gástrica , Helicobacter pylori , Técnicas Imunoenzimáticas , Fenótipo , Lesões Pré-Cancerosas
7.
Genet. mol. biol ; 25(3): 259-263, Sept. 2002. tab, graf
Artigo em Inglês | LILACS | ID: lil-335763

RESUMO

The expression of the ABH and Lewis blood groups was determined in blood and saliva samples from two semi-isolated Black communities of Northern Brazil: Cametá and Alcântara. The distributions of ABO blood group phenotypes and the ABH secretor status frequencies showed no significant differences between these populations. In contrast, there was a difference regarding the frequency of the red blood cell Le(a-b-) phenotypes, associated with erythrocyte/saliva discordance, as confirmed by the observation that individuals with Le(a-b-) red cells have the Lewis antigen in their saliva, resulting in a nongenuine Le(a-b-) phenotype, whose frequency was higher in Alcântara


Assuntos
Humanos , População Negra , Brasil , Saliva , Sistema ABO de Grupos Sanguíneos/análise , Antígenos do Grupo Sanguíneo de Lewis/análise , Ensaio de Imunoadsorção Enzimática , Fenótipo
8.
Arq Gastroenterol ; 39(4): 222-32, 2002.
Artigo em Português | MEDLINE | ID: mdl-12870081

RESUMO

BACKGROUND: The major cause for chronic gastritis in human is the infection by the Helicobacter pylori. The blood group antigens present at the gastric mucous are described as possible receptor for this bacteria in the epithelium. The alterations in the expression of blood group patterns are associated with the development of gastric cancer. OBJECTIVES: Verify the H. pylori prevalence and examine the immunohistochemical distribution of the ABH and Lewis antigens expression to correlate with histopathological alterations. PATIENTS AND METHODS: From 63 chronic gastritis patients were investigated gastric biopsies, blood and saliva samples by dot-blot-ELISA, indirect immunoperoxidase and hematoxylin-eosin and Gram. RESULTS: No significant association between the presence of the bacteria and the ABH, Lewis and Secretor phenotype was found. For the majority of the patients the antigen expression of the ABH and Lewis blood group was restricted mainly to the foveola epithelium of the gastric mucosa, similar to the saliva. The inappropriate expression of these antigens occurred always in the presence of H. pylori and/or preneoplastic alterations of the gastric mucosa. In areas with intestinal metaplasias we also observed reduced reactivity for the H and Le b antigens and mainly the induced expression of Le . CONCLUSION: Alterations in the pattern of the glycosylation of this antigens are interesting, because they reflect different stages in the cellular differentiation and become potential markers in the diagnostic evaluation and prognosis of gastric pathologies.


Assuntos
Sistema ABO de Grupos Sanguíneos , Mucosa Gástrica/microbiologia , Gastrite Atrófica/sangue , Infecções por Helicobacter/sangue , Helicobacter pylori , Antígenos do Grupo Sanguíneo de Lewis , Neoplasias Gástricas/sangue , Biomarcadores/sangue , Feminino , Mucosa Gástrica/patologia , Gastrite Atrófica/microbiologia , Humanos , Técnicas Imunoenzimáticas , Masculino , Pessoa de Meia-Idade , Fenótipo , Lesões Pré-Cancerosas/sangue , Neoplasias Gástricas/microbiologia
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