949 resultados para Lewis histo-blood group system
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FUNDAMENTOS: Lesão discoide é a manifestação cutânea mais comum do lúpus eritematoso, e formas cutâneas crônicas apresentam características imunológicas próprias, direcionadas ao polo Th1. Diversas doenças possuem associação com grupos sanguíneos, o que não foi ainda estudado no lúpus discoide. OBJETIVO: Investigar a associação entre tipos sanguíneos (ABO e Rh) e lúpus eritematoso discoide. MÉTODOS: Estudo prospectivo tipo transversal envolvendo tipagem sanguínea ABO e Rh, inquérito de dados clínicos e dosagem de FAN e C4 de portadores de lúpus discoide sem critérios de doença sistêmica, atendidos em hospital universitário. RESULTADOS: Foram incluídos no estudo 69 pacientes, sendo 71,0% do sexo feminino (p 1:160, em 31,9%; e níveis baixos de C4, em 8,7%. Não houve diferença significativa entre as frequências dos grupos sanguíneos dos pacientes e da população local; entretanto, o grupo A foi associado às formas disseminadas da doença (OR 4,1 e p < 0,05). CONCLUSÕES: Grupos sanguíneos de pacientes com lúpus discoide apresentam frequência semelhante à da população; porém, formas clínicas disseminadas foram mais prevalentes entre portadores do grupo A.
Sequence, evolution and ligand binding properties of mammalian Duffy antigen/receptor for chemokines
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The Duffy antigen/receptor for chemokine, DARC, acts as a widely expressed promiscuous chemokine receptor and as the erythrocyte receptor for Plasmodium vivax. To gain insight into the evolution and structure/function relations of DARC, we analyzed the binding of anti-human Fy monoclonal antibodies (mAbs) and human chemokines to red blood cells (RBCs) from 11 nonhuman primates and two nonprimate mammals, and we elucidated the structures of the DARC genes from gorilla, gibbon, baboon, marmoset, tamarin, night monkey and cattle. CXCL-8 and CCL-5 chemokine binding analysis indicated that the promiscuous binding profile characteristic of DARC is conserved across species. Among three mAbs that detected the Fy6 epitope by flow cytometric analysis of human and chimpanzee RBCs, only one reacted with night monkey and squirrel monkey. Only chimpanzee RBCs bound a significant amount of the anti-Fy3 mAb. Fy3 was also poorly detected on RBCs from gorilla, baboon and rhesus monkey, but not from new world monkeys. Alignment of DARC homologous sequences allowed us to construct a phylogenetic tree in which all branchings were in accordance with current knowledge of primate phylogeny. Although DARC was expected to be under strong internal and external selection pressure, in order to maintain chemokine binding and avoid Plasmodium vivax binding, respectively, our present study did not provide arguments in favor of a selection pressure on the extracellular domains involved in ligand specificity. The amino acid variability of DARC-like polypeptides was found to be well correlated with the hydrophylicity indexes, with the highest divergence on the amino-terminal extracellular domain. Analysis of the deduced amino acid sequences highlighted the conservation of some amino acid residues, which should prove to be critical for the structural and functional properties of DARC.
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Persistently low white blood cell count (WBC) and neutrophil count is a well-described phenomenon in persons of African ancestry, whose etiology remains unknown. We recently used admixture mapping to identify an approximately 1-megabase region on chromosome 1, where ancestry status (African or European) almost entirely accounted for the difference in WBC between African Americans and European Americans. To identify the specific genetic change responsible for this association, we analyzed genotype and phenotype data from 6,005 African Americans from the Jackson Heart Study (JHS), the Health, Aging and Body Composition (Health ABC) Study, and the Atherosclerosis Risk in Communities (ARIC) Study. We demonstrate that the causal variant must be at least 91% different in frequency between West Africans and European Americans. An excellent candidate is the Duffy Null polymorphism (SNP rs2814778 at chromosome 1q23.2), which is the only polymorphism in the region known to be so differentiated in frequency and is already known to protect against Plasmodium vivax malaria. We confirm that rs2814778 is predictive of WBC and neutrophil count in African Americans above beyond the previously described admixture association (P = 3.8 x 10(-5)), establishing a novel phenotype for this genetic variant.
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Peter J. D'Adamo, autor do livro Eat Right For Your Type, escreve que o grupo O representa o primeiro tipo sangüíneo que surgiu nos humanos e também afirma que os grupos sangüíneos constituem as bases do sistema imune. Recentes estudos filogenéticos realizados em primatas humanos e não humanos estabeleceram que o gene A representa a forma ancestral dos genes que ocupam o locus ABO. Associações entre os grupos sangüíneos ABO, doenças infecciosas, não infecciosas e imunodeficiências também foram relatadas. Diante das proposições do autor, as quais se opõem às informações resultantes de recentes estudos moleculares e filogenéticos, nossa intenção é apresentar algumas reflexões sobre a genética e a evolução dos genes do sistema ABO e as conexões deste sistema com o sistema imune.
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Primary sensory neurons in the vertebrate olfactory systems are characterised by the differential expression of distinct cell surface carbohydrates. We show here that the histo-blood groups Sda (or CT1 antigen) and H are expressed by primary sensory neurons in the olfactory system, while the blood group A carbohydrate is expressed by a subset of vomeronasal neurons only in the developing accessory olfactory system. We have used both loss-of-function and gain-of-function approaches to manipulate expression of these carbohydrates in the olfactory system. In null mutant mice lacking the alpha(1,2)fucosyltransferase FUT1, the blood group H and A carbohydrates were not expressed in the olfactory systems which caused delayed development of the nerve fibre and glomerular layers in the main olfactory bulb. In contrast, ubiquitous expression of blood group A on olfactory axons in gain-of-function transgenic mice perturbed the ability of vomeronasal axons to terminate in the accessory olfactory bulb and affected the selective targeting of axons in the main olfactory bulb. During regeneration following bulbectomy, vomeronasal axons were unable to effectively sort out from the main olfactory axons when blood group A was misexpressed. These results provide in vivo evidence for a role of specific cell surface carbohydrates during development and regeneration of the olfactory nerve pathways.
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Contexte. Les phénotypes ABO et Rh(D) des donneurs de sang ainsi que des patients transfusés sont analysés de façon routinière pour assurer une complète compatibilité. Ces analyses sont accomplies par agglutination suite à une réaction anticorps-antigènes. Cependant, pour des questions de coûts et de temps d’analyses faramineux, les dons de sang ne sont pas testés sur une base routinière pour les antigènes mineurs du sang. Cette lacune peut résulter à une allo-immunisation des patients receveurs contre un ou plusieurs antigènes mineurs et ainsi amener des sévères complications pour de futures transfusions. Plan d’étude et Méthodes. Pour ainsi aborder le problème, nous avons produit un panel génétique basé sur la technologie « GenomeLab _SNPstream» de Beckman Coulter, dans l’optique d’analyser simultanément 22 antigènes mineurs du sang. La source d’ADN provient des globules blancs des patients préalablement isolés sur papiers FTA. Résultats. Les résultats démontrent que le taux de discordance des génotypes, mesuré par la corrélation des résultats de génotypage venant des deux directions de l’ADN, ainsi que le taux d’échec de génotypage sont très bas (0,1%). Également, la corrélation entre les résultats de phénotypes prédit par génotypage et les phénotypes réels obtenus par sérologie des globules rouges et plaquettes sanguines, varient entre 97% et 100%. Les erreurs expérimentales ou encore de traitement des bases de données ainsi que de rares polymorphismes influençant la conformation des antigènes, pourraient expliquer les différences de résultats. Cependant, compte tenu du fait que les résultats de phénotypages obtenus par génotypes seront toujours co-vérifiés avant toute transfusion sanguine par les technologies standards approuvés par les instances gouvernementales, les taux de corrélation obtenus sont de loin supérieurs aux critères de succès attendus pour le projet. Conclusion. Le profilage génétique des antigènes mineurs du sang permettra de créer une banque informatique centralisée des phénotypes des donneurs, permettant ainsi aux banques de sang de rapidement retrouver les profiles compatibles entre les donneurs et les receveurs.
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
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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.
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RACIONAL: A aderência do Helicobacter pylori à mucosa gástrica humana é pré-requisito para sua colonização e o desenvolvimento da gastrite crônica. Os antígenos de grupos sangüíneos, presentes no muco gástrico, são descritos como prováveis receptores da bactéria neste epitélio. A expressão alterada destes antígenos está associada ao desenvolvimento do câncer gástrico. OBJETIVOS: Verificar a ocorrência do Helicobacter pylori e a distribuição da expressão dos antígenos ABH e Lewis correlacionada com as alterações 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 colorações do Gram modificado e hematoxilina-eosina. RESULTADOS: Não foram encontradas associações significativas entre a presença da bactéria e os fenótipos de grupos sangüíneos ABH, Lewis e Secretor. Na maioria dos pacientes, a expressão dos antígenos ABH e Lewis, estava restrita principalmente ao epitélio foveolar da mucosa gástrica, concordando com a expressão ao nível salivar. A expressão inapropriada desses antígenos ocorria sempre na infecção pelo Helicobacter pylori e/ou alterações pré-neoplásicas da mucosa gástrica. Em áreas com metaplasia intestinal foi observada a redução da reatividade para os antígenos H e Leb, e principalmente o aumento de Leª. CONCLUSÃO: Alterações no padrão de glicosilação destes antígenos refletem diferentes estágios de diferenciação celular e são marcadores potenciais na avaliação diagnóstica e prognóstica das patologias gástricas.
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Zelladhäsions- und Zellerkennungsphänomene spielen eine entscheidende Rolle im biologischen Geschehen: So findet die Kommunikation zwischen Zellen zu einem großen Teil zwischen membranständigen Adhäsionsmolekülen und ebenfalls membranständigen Liganden auf Nachbarzellen statt. Zu diesen Adhäsionsmolekülen gehören die Selektine, die von fundamentaler Bedeutung für die Bekämpfung von Entzündungskrankheiten und damit für die Funktionsweise unseres Immunsystems sind. Tritt eine Entzündung in unserem Körper auf, so sind Selektine an Adhäsionsprozessen beteiligt, die zur Auswanderung von Leukozyten aus dem Blutstrom in das entzündete Gewebe führen. Diese auswandernden Zellen enthalten eine Vielzahl von Wirkstoffen, die Krankheitserreger bekämpfen, aber auch körpereigenes Gewebe angreifen können. Viele Krankheitsbilder, die mit akut oder chronisch entzündlichen Prozessen einhergehen, hängen mit einer Dysregulation der Selektine zusammen. In diesen Fällen werden übermäßig Selektine exprimiert und es kommt zu einer lokal überschießenden Akkumulation von Leukozyten, die zu Schädigungen von gesundem Gewebe führen kann. rnZu diesen Krankheiten gehören z.B. die rheumatoide Arthritis, die myocardialen Ischämie, Psoriasis sowie Asthma und Allergien. Auch bei der Abstoßung von Transplantaten und Tumormetastasierung wurde eine Beteiligung der Selektine nachgewiesen. Eine Strategie gegen diese unerwünschten Effekte ist die selektive Inhibierung der Selektine, welche aufgrund der bedeutenden Rolle der Selektine in der Genese zahlreicher Krankheiten, von großem pharmazeutischen Interesse ist. rnIn der vorliegenden Arbeit ist die Entwicklung chemischer Synthesen von Verbindungen beschrieben, welche selektininhibierende Eigenschaften aufweisen sollen. Solche sog. Mimetika, die wie die natürlichen Liganden mit den Selektinen wechselwirken, sind nicht nur potenzielle Medikamente, sondern können auch durch veränderte Affinität zur Aufklärung von selektinvermittelten Zelladhäsionsprozessen dienen.rn
Profit Analysis of Small Holder Dairy Cattle Farm on Group and Individual System in Banyumas Regency
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This research is aimed to study production, technical and the profit of group and individual system on smallholder dairy cattle farm. The research has been conducted in Banyumas Regency. Data collection was done by surveying about 80 farmers, Unit Output Price Cobb-Douglas Profit Function estimation employed Ordinary Leas Square (OLS) method. The different of variable from the result of profit estimation. Profit function analysis on group system showed that manpower pay, animal age, lactation period, lactation month and farmer education have a significant influence on the profit. Whereas, on individual system influence of manpower pay, animal age and lactation month were significant on the profit. Dummy variable showed that group system has more profit than individual system, it was because on group system; (1) has cheaper price on forage and concentrate cost, (2) has higher average of production result, and (3) has higher price of milk per unit. (Animal Production 4(2): 94-100 (2002) Key words : Profit, Group and Individual System
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Charcot-Marie-Tooth neuropathy type 1 (CMT1) is an autosomal dominant disorder of peripheral nerve. The gene for CMT1 was originally localized to chromosome 1 by linkage to the Duffy blood group, but it has since been shown that not all CMT1 pedigrees show this linkage. We report here the results of linkage studies using five chromosome 1 markers - Duffy (Fy), antithrombin III (AT3), renin (REN), β-nerve growth factor (NGFB), and salivary amylase (AMY1) - in 16 CMT1 pedigrees. The total lod scores exclude close linkage of CMT1 to any of these markers. However, individual families show probable linkage of CMT1 to Duffy, AT3, and/or AMY1. No linkage was indicated with REN or NGFB. These results indicate that possible location of a CMT1 gene between the AMY1 and AT3 loci at p21 and q23, respectively, on chromosome 1 and support the theory that there is at least one other CMT1 gene.
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Results of Duffy (Fy) linkage confirm genetic heterogeneity in Charcot-Marie-Tooth disease type 1 (CMT1). Of 11 families informative for Fy, four showed probable linkage with CMT1, seven showed probable non-linkage and two showed definite non-linkage. These results suggest that Fy linked CMT1 may be less common than previously thought. These results combined with those of another DNA probe for the antithrombin III gene confirm that there are at least two gene loci for CMT1, termed 1A and 1B.
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Cell adhesion is crucial to many biological processes, such as inflammatory responses, tumor metastasis and thrombosis formation. Recently a commercial surface plasmon resonance (SPR)-based BIAcore biosensor has been extended to determine cell binding mediated by surface-bound biomolecular interactions. How such cell binding is quantitatively governed by kinetic rates and regulating factors, however, has been poorly understood. Here we developed a novel assay to determine the binding kinetics of surface-bound biomolecular interactions using a commercial BIAcore 3000 biosensor. Human red blood cells (RBCs) presenting blood group B antigen and CM5 chip bearing immobilized anti-B monoclonal antibody (mAb) were used to obtain the time courses of response unit, or sensorgrams, when flowing RBCs over the chip surface. A cellular kinetic model was proposed to correlate the sensorgrams with kinetic rates. Impacts of regulating factors, such as cell concentration, flow duration and rate, antibody-presenting level, as well as pH value and osmotic pressure of suspending medium were tested systematically, which imparted the confidence that the approach can be applied to kinetic measurements of cell adhesion mediated by surface-bound biomolecular interactions. These results provided a new insight into quantifying cell binding using a commercial SPR-based BIAcore biosensor.