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1.
Nat Genet ; 27(2): 218-21, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11175794

RESUMO

Type 1 diabetes (T1D; or insulin-dependent diabetes mellitus, IDDM) is an autoimmune disease with both genetic and environmental components. In addition to the human leukocyte antigen (HLA) complex, the single major genetic contributor of susceptibility, an unknown number of other unidentified genes are required to mediate disease. Although many loci conferring susceptibility to T1D have been mapped, their identification has proven problematic due to the complex nature of this disease. Our strategy for finding T1D susceptibility genes has been to test for human homologues of loci implicated in diabetes-prone NOD (non-obese diabetic) mice, together with application of biologically relevant stratification methods. We report here a new susceptibility locus, IDDM18, located near the interleukin-12 (IL-12)p40 gene, IL12B. Significant bias in transmission of IL12B alleles was observed in affected sibpairs and was confirmed in an independent cohort of simplex families. A single base change in the 3' UTR showed strong linkage disequilibrium with the T1D susceptibility locus. The IL12B 3' UTR alleles showed different levels of expression in cell lines. Variation in IL-12p40 production may influence T-cell responses crucial for either mediating or protecting against this and other autoimmune diseases.


Assuntos
Diabetes Mellitus Tipo 1/genética , Interleucina-12/genética , Desequilíbrio de Ligação , Regiões 3' não Traduzidas , Alelos , Frequência do Gene , Predisposição Genética para Doença , Genótipo , Humanos , Íntrons , Polimorfismo Genético , Regiões Promotoras Genéticas
2.
Br J Cancer ; 106(10): 1598-604, 2012 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-22516948

RESUMO

BACKGROUND: The objectives of this phase I study were to assess the safety and tolerability of E7080 in patients with advanced, refractory solid tumours; to determine the maximum tolerated dose (MTD) and pharmacokinetics profile of E7080; and to explore preliminary evidence of its anti-tumour efficacy. METHODS: E7080 was administered orally in escalating doses on a once-daily continuous schedule in 28-day cycles to eligible patients. Samples for pharmacokinetic analyses were collected on days 1, 8, 15 and 22 of cycle 1 and day 1 of cycle 2. Anti-tumour efficacy was assessed every two cycles. RESULTS: Eighty-two patients received E7080 in dose cohorts from 0.2 to 32 mg. Dose-limiting toxicities were grade 3 proteinuria (two patients) at 32 mg, and the MTD was defined as 25 mg. The most frequently observed cumulative toxicities (all grades) were hypertension (40% of patients), diarrhoea (45%), nausea (37%), stomatitis (32%) and vomiting (23%). Seven patients (9%) had a partial response and 38 patients (46%) had stable disease as best response. E7080 has dose-linear kinetics with no drug accumulation after 4 weeks' administration. CONCLUSION: E7080 is well tolerated at doses up to 25 mg per day. Encouraging anti-tumour efficacy was observed in patients with melanoma and renal cell carcinoma.


Assuntos
Neoplasias/tratamento farmacológico , Compostos de Fenilureia/uso terapêutico , Inibidores de Proteínas Quinases/uso terapêutico , Proteínas Tirosina Quinases/antagonistas & inibidores , Quinolinas/uso terapêutico , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Dose Máxima Tolerável , Pessoa de Meia-Idade , Compostos de Fenilureia/efeitos adversos , Compostos de Fenilureia/farmacocinética , Inibidores de Proteínas Quinases/efeitos adversos , Inibidores de Proteínas Quinases/farmacocinética , Quinolinas/efeitos adversos , Quinolinas/farmacocinética
3.
Tissue Antigens ; 78(1): 11-20, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21501118

RESUMO

HLA-B57 and HLA-B58 are major histocompatibility class (MHC)-I allotypes that are potentially predictive of important clinical immune phenotypes. HLA-B*5701 is strongly associated with hypersensitivity to the HIV drug abacavir, liver toxicity from the antibiotic flucloxacillin and is a marker for slow progression of HIV AIDS. HLA-B*5801 is associated with hypersensitivity to allopurinol used to treat hyperuricaemia and recurrent gout. Here we describe a monoclonal antibody (mAb) specific for HLA-B57 and HLA-B58 that provides an inexpensive and sensitive screen for these MHC-I allotypes. The usefulness of HLA-B57 screening for prediction of abacavir hypersensitivity was shown in three independent laboratories, including confirmation of the mAb sensitivity and specificity in a cohort of patients enrolled in the PREDICT-1 trial. Our data show that patients who test negative by mAb screening comprise 90%-95% of all individuals in most human populations and require no further human leukocyte antigen (HLA) typing. Patients who test positive by mAb screening should proceed to high-resolution typing to ascertain the presence of HLA-B*5701 or HLA-B*5801. Hence, mAb screening provides a low-cost alternative to high-resolution typing of all patients and lends itself to point-of-care diagnostics and rapid ascertainment of low-risk patients who can begin immediate therapy with abacavir, flucloxacillin or allopurinol.


Assuntos
Hipersensibilidade a Drogas/prevenção & controle , Antígenos HLA-B/análise , Programas de Rastreamento/métodos , Sequência de Aminoácidos , Animais , Anticorpos Monoclonais/biossíntese , Anticorpos Monoclonais/isolamento & purificação , Anticorpos Monoclonais/metabolismo , Anticorpos Monoclonais/farmacologia , Formação de Anticorpos , Especificidade de Anticorpos , Células Cultivadas , Hipersensibilidade a Drogas/genética , Hipersensibilidade a Drogas/imunologia , Ensaio de Imunoadsorção Enzimática , Antígenos HLA-B/genética , Antígenos HLA-B/imunologia , Teste de Histocompatibilidade/métodos , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Modelos Moleculares , Dados de Sequência Molecular , Fatores de Tempo
4.
Tissue Antigens ; 76(2): 87-95, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20403141

RESUMO

The introduction into routine diagnostic laboratories of solid phase assays for human leukocyte antigen (HLA) antibody detection has resulted in the application of new laboratory matching algorithms in clinical organ transplantation which have improved pre-transplant detection of immunization, in turn resulting in avoidance of rejection in many cases which until their introduction would not have been possible using the historical complement dependent serological techniques. There have been two generations of solid phase assays introduced into routine practice, namely, the enzyme-linked immunosorbent assay (ELISA) technique and the use of fluorescent beads with HLA molecules bound to their surface which can either be used in conventional flow cytometry or in conjunction with Luminex instrumentation, the latter having become the most popular approach. The use of the fluorescent bead techniques has raised interesting questions both with respect to technical performance and the interpretation of the results obtained. The advantages of bead technology for HLA antibody determination and the technical issues requiring resolution are the subject of this review.


Assuntos
Antígenos HLA/imunologia , Imunoensaio/métodos , Isoanticorpos/análise , Proteínas do Sistema Complemento/metabolismo , Ensaio de Imunoadsorção Enzimática/métodos , Imunofluorescência/métodos , Antígenos de Histocompatibilidade Classe I/imunologia , Teste de Histocompatibilidade , Humanos , Imunidade Inata , Imunoglobulina M/análise , Imunoglobulina M/sangue , Isoanticorpos/sangue , Imunologia de Transplantes , Microglobulina beta-2/sangue , Microglobulina beta-2/imunologia
5.
Tissue Antigens ; 74(1): 17-21, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19392788

RESUMO

Human leucocyte antigen (HLA)-DRB1*1501 and other class II alleles influence susceptibility to multiple sclerosis (MS), but their contribution if any to the clinical course of MS remains uncertain. Here, we have investigated DRB1 alleles in a large sample of 1230 Australian MS cases, with some enrichment for subjects with primary progressive (PPMS) disease (n = 246) and 1210 healthy controls. Using logistic regression, we found that DRB1*1501 was strongly associated with risk (P = 7 x 10(-45)), as expected, and after adjusting for DRB1*1501, a predisposing effect was also observed for DRB1*03 (P = 5 x 10(-7)). Individuals homozygous for either DRB1*15 or DRB1*03 were considerably more at risk of MS than heterozygotes and non-carriers. Both the DRB1*04 and the DRB1*01/DRB1*15 genotype combination, respectively, protected against PPMS in comparison to subjects with relapsing disease. Together, these data provide further evidence of heterogeneity at the DRB1 locus and confirm the importance of HLA variants in the phenotypic expression of MS.


Assuntos
Predisposição Genética para Doença , Antígenos HLA-DR/genética , Esclerose Múltipla/genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Alelos , Austrália/epidemiologia , Feminino , Frequência do Gene , Cadeias HLA-DRB1 , Humanos , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla/epidemiologia , Adulto Jovem
6.
Science ; 272(5269): 1811-3, 1996 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-8650584

RESUMO

Insulin-dependent diabetes mellitus (IDDM) is a multigenic autoimmune disease. An IDDM susceptibility gene was mapped to chromosome 2q34. This gene may act early in diabetogenesis, because "preclinical" individuals also showed linkage. Human leukocyte antigen (HLA)-disparate, but not HLA-identical, sibs showed linkage, which was even stronger in families with affected females. The genes encoding insulin-like growth factor-binding proteins 2 and 5 were mapped to a 4-megabase pair interval near this locus. These results indicate the existence of a gene that acts at an early stage in IDDM development, screening for which may identify a specific subset of at-risk individuals.


Assuntos
Cromossomos Humanos Par 2/genética , Diabetes Mellitus Tipo 1/genética , Ligação Genética , Marcadores Genéticos , Alelos , Animais , Autoanticorpos/análise , Mapeamento Cromossômico , Feminino , Frequência do Gene , Predisposição Genética para Doença , Antígenos HLA/genética , Humanos , Proteína 2 de Ligação a Fator de Crescimento Semelhante à Insulina/genética , Proteína 5 de Ligação a Fator de Crescimento Semelhante à Insulina/genética , Ilhotas Pancreáticas/imunologia , Masculino , Camundongos , Camundongos Endogâmicos NOD/genética , Repetições de Microssatélites
7.
Vaccine ; 37(5): 690-692, 2019 01 29.
Artigo em Inglês | MEDLINE | ID: mdl-30392767

RESUMO

Human papillomavirus (HPV) vaccines are currently utilised globally in national immunisation programmes. Many new European migrants have settled in the United Kingdom (UK) since the 2004 European Union expansion with approximately 91,000 Polish people resident in Scotland. Following anecdotal reports from several NHS Boards within Scotland of lower HPV vaccine uptake in Polish communities compared with other ethnic minorities, an extract containing both forename and surname, was taken from the Scottish Immunisation Recall System (SIRS) for all girls in S2 and S3 in school years 2014/15 to 2016/17. We then used the OnoMap algorithm software to derive ethnicity. OnoMap identified between 289 and 321 age-eligible girls as Polish with significant disparity noted for completed HPV vaccine uptake between UK (87.2-89.8%) and Polish ethnicities (69.7-77.2%) (P < 0.01). Preliminary discussions with Polish families suggest that vaccine programme differences, trust in medical/healthcare practitioners, and cultural influences may be important drivers of acceptance.


Assuntos
Infecções por Papillomavirus/prevenção & controle , Vacinas contra Papillomavirus/administração & dosagem , Aceitação pelo Paciente de Cuidados de Saúde/etnologia , Migrantes/psicologia , Neoplasias do Colo do Útero/prevenção & controle , Vacinação/psicologia , Adolescente , Estudos de Coortes , Feminino , Humanos , Aceitação pelo Paciente de Cuidados de Saúde/psicologia , Polônia/etnologia , Escócia , Software
8.
Genes Immun ; 9(7): 624-30, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18650830

RESUMO

A recent genome-wide association study (GWAS) conducted by the International Multiple Sclerosis Genetics Consortium (IMSGC) identified a number of putative MS susceptibility genes. Here we have performed a replication study in 1134 Australian MS cases and 1265 controls for 17 risk-associated single nucleotide polymorphisms (SNPs) reported by the IMSGC. Of 16 SNPs that passed quality control filters, four, each corresponding to a different non-human leukocyte antigen (HLA) gene, were associated with disease susceptibility: KIAA0350 (rs6498169) P=0.001, IL2RA (rs2104286) P=0.033, RPL5 (rs6604026) P=0.041 and CD58 (rs12044852) P=0.042. There was no association (P=0.58) between rs6897932 in the IL7R gene and the risk of MS. No interactions were detected between the replicated IMSGC SNPs and HLA-DRB1*15, gender, disease course, disease progression or age-at-onset. We used a novel Bayesian approach to estimate the extent to which our data increased or decreased evidence for association with the six most-associated IMSGC loci. These analyses indicated that even modest P-values, such as those reported here, can contribute markedly to the posterior probability of 'true' association in replication studies. In conclusion, these data provide support for the involvement of four non-HLA genes in the pathogenesis of MS, and combined with previous data, increase to genome-wide significance (P=3 x 10(-8)) evidence of an association between KIAA0350 and risk of disease.


Assuntos
Antígenos CD58/genética , Predisposição Genética para Doença , Subunidade alfa de Receptor de Interleucina-2/genética , Lectinas Tipo C/genética , Proteínas de Transporte de Monossacarídeos/genética , Esclerose Múltipla/genética , Proteínas Ribossômicas/genética , Adolescente , Adulto , Idoso , Austrália , Estudos de Casos e Controles , Criança , Feminino , Estudo de Associação Genômica Ampla , Humanos , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único
9.
Am J Transplant ; 8(1): 121-32, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18093278

RESUMO

Allogeneic solid organ transplantation often occurs across multiple donor-recipient HLA mismatches with consequent risk of allograft rejection. However, there is growing evidence that not all HLA mismatches are equivalent in their stimulation of allogeneic T cells making it important to determine which of these might be more significant as predictors of allograft rejection. To this end, we used defined antigen-presenting cell (APC) transfectants expressing single MHC-I allotypes as target cells that could discriminate the relative contribution of individual mismatched MHC-I allotypes to direct T-cell alloreactivity. We demonstrate remarkably reproducible patterns of immunodominance in reactivity across mismatched MHC-I allotypes. These patterns are HLA context-dependent, partly reflecting alloantigenic competition in responder cell responses. In strong alloresponses, we also observed an increased percentage of alloreactive T(CD8) cells in female responders, regardless of the stimulator gender, highlighting HLA-independent factors in the potency of the alloresponse. This approach provides a potential measure of specific alloreactive T cells that could be used in clinical practice for selection of donors, assessment of posttransplant outcomes, modulation of immunosuppression and detection of rejection episodes.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Epitopos Imunodominantes/imunologia , Ativação Linfocitária/imunologia , Caracteres Sexuais , Ligação Competitiva , Linfócitos T CD8-Positivos/metabolismo , Linhagem Celular , Testes Imunológicos de Citotoxicidade , Feminino , Antígenos HLA-D/imunologia , Antígenos HLA-D/metabolismo , Antígenos de Histocompatibilidade Classe I/imunologia , Antígenos de Histocompatibilidade Classe I/metabolismo , Teste de Histocompatibilidade , Humanos , Epitopos Imunodominantes/metabolismo , Masculino , Transplante Homólogo
10.
J Clin Invest ; 76(5): 1965-70, 1985 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-2414326

RESUMO

RM2.184, a mouse IgG2a monoclonal antibody, recognizes a polymorphic determinant on the complement receptor for C3bi which is present on granulocytes and monocytes. The RM2.184 epitope is distinct from the monomorphic determinant recognized by the monoclonal antibody OKM1. The RM2.184 epitope is probably on the alpha subunit and dependent on the association of the alpha and beta subunits for its configuration, as it can not be detected after the subunits have been dissociated. The phenotypic frequency of the RM2.184 antigen is approximately 14%, and its segregation in families is independent of HLA and consistent with an autosomal co-dominant mode of inheritance.


Assuntos
Anticorpos Monoclonais , Receptores de Complemento/genética , Epitopos , Citometria de Fluxo , Imunofluorescência , Granulócitos/imunologia , Heterozigoto , Humanos , Monócitos/imunologia , Linhagem , Polimorfismo Genético , Conformação Proteica , Receptores de Complemento/imunologia , Receptores de Complemento 3b , Formação de Roseta
11.
J Clin Invest ; 100(11): 2783-92, 1997 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-9389743

RESUMO

Mucin 1 (MUC1) is a large complex glycoprotein that is highly expressed in breast cancer, and as such could be a target for immunotherapy. In mice, human MUC1 is highly immunogenic, particularly when conjugated to mannan, where a high frequency of CD8(+) MHC-restricted cytotoxic T lymphocytes is induced, accompanied by tumor protection. On this basis, a clinical trial was performed in which 25 patients with advanced metastatic carcinoma of breast, colon, stomach, or rectum received mannan-MUC1 in increasing doses. After 4 to 8 injections, large amounts of IgG1 anti-MUC1 antibodies were produced in 13 out of 25 patients (with antibody titers by ELISA of 1/320-1/20,480). Most of the antibodies reacted to the epitopes STAPPAHG and PAPGSTAP. In addition, T cell proliferation was found in 4 out of 15 patients, and CTL responses were seen in 2 out of 10 patients. Mannan-MUC1 can immunize patients, particularly for antibody formation, and to a lesser extent, cellular responses. It remains to be seen whether such responses have antitumor activity.


Assuntos
Adenocarcinoma/imunologia , Anticorpos/imunologia , Neoplasias da Mama/imunologia , Vacinas Anticâncer/imunologia , Neoplasias do Colo/imunologia , Mananas/imunologia , Mucina-1/imunologia , Neoplasias Retais/imunologia , Neoplasias Gástricas/imunologia , Linfócitos T/imunologia , Adenocarcinoma/fisiopatologia , Idoso , Sequência de Aminoácidos , Neoplasias da Mama/fisiopatologia , Divisão Celular , Neoplasias do Colo/fisiopatologia , Testes Imunológicos de Citotoxicidade , Epitopos de Linfócito B/imunologia , Feminino , Humanos , Isotipos de Imunoglobulinas , Masculino , Mananas/administração & dosagem , Dados de Sequência Molecular , Mucina-1/administração & dosagem , Proteínas Recombinantes de Fusão/administração & dosagem , Proteínas Recombinantes de Fusão/imunologia , Neoplasias Retais/fisiopatologia , Neoplasias Gástricas/fisiopatologia , Linfócitos T/citologia
12.
Bone Marrow Transplant ; 37(8): 773-9, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16518429

RESUMO

Methotrexate (MTX), used as a graft-versus-host disease (GvHD) prophylactic agent in hematopoietic stem cell transplantation (HSCT), exerts its effect via folate cycle inhibition. A critical enzyme involved in folate metabolism is 5,10-methylenetetrahydrofolate reductase (MTHFR). We examined the association of a single nucleotide polymorphism (SNP) at position 677 in the MTHFR gene on GvHD outcomes in allogeneic HSCT patients administered MTX. MTHFR genotyping was performed by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) on 193 HSCT patients and donors. A total of 140 patients were transplanted with an HLA-matched related donor and 53 with an unrelated donor. GvHD outcomes were compared between genotypes by univariate and multivariate analysis. The combined donor 677CT and TT genotypes were associated with a decreased incidence of GvHD (acute and chronic combined) in HSCT recipients with an HLA-matched related donor (75% at 1 year in the CT and TT group compared with 91% in the wild type CC group, P=0.01), increased time to onset of first GvHD (P=0.001) and time to first GvHD treated with systemic therapy (P=0.022). Unrelated donor MTHFR genotype was not associated with outcome parameters and no associations of recipient genotype in either related or unrelated donor cohorts were observed.


Assuntos
Genótipo , Transplante de Células-Tronco Hematopoéticas/métodos , Metotrexato/uso terapêutico , Metilenotetra-Hidrofolato Redutase (NADPH2)/genética , Doadores de Tecidos , Adolescente , Adulto , Idoso , Estudos de Coortes , DNA/química , Feminino , Ácido Fólico/metabolismo , Doença Enxerto-Hospedeiro , Humanos , Masculino , Pessoa de Meia-Idade , Modelos Estatísticos , Análise Multivariada , Mutação , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Polimorfismo de Nucleotídeo Único , Modelos de Riscos Proporcionais , Transplante de Células-Tronco , Células-Tronco/citologia , Fatores de Tempo , Condicionamento Pré-Transplante , Transplante Homólogo , Resultado do Tratamento
13.
Biochim Biophys Acta ; 1539(1-2): 58-70, 2001 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-11389968

RESUMO

We present the first recorded Raman spectra of haemoglobin in both the R and T states from within a single living erythrocyte using 632.8 nm excitation. Bands characteristic of low spin haems are observed in oxygenated and carboxylated erythrocytes at approx. 1636 (nu(10)), 1562-1565 (nu(2)), 1250-1245 cm(-1) (nu(13)) and 1226-1224 cm(-1) (nu(5)+nu(8)). The spectra of deoxygenated and methaemoglobin erythrocytes have characteristic high spin bands at approx. 1610-1606 cm(-1) (nu(10)), 1582-1580 (nu(37)), 1547-1544 (nu(11)), 1230-1220 cm(-1) (nu(13)) and 1215-1210 cm(-1) (nu(5)+nu(8)). Bands at 1172 (nu(30)), 976 (nu(45)) and 672 (nu(7)) cm(-1) appear to be enhanced at 632.8 nm in low spin haems. The oxidation state marker band (nu(4)) at 1364-1366 cm(-1) appeared invariant within this domain in all single cells and conditions investigated contrary to other resonance Raman studies on haem isolates. The information gained by in vivo single erythrocyte molecular analysis has important ramifications to the understanding of fundamental physiological processes and may have applications in the diagnosis and treatment of red blood cell disorders.


Assuntos
Eritrócitos/química , Hemoglobinas/química , Análise Espectral Raman/métodos , Humanos , Lasers , Espectrofotometria
14.
Diabetes ; 37(7): 926-9, 1988 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-3260201

RESUMO

We have shown in previous studies that the TA10-subtype of HLA-DQw3 is significantly increased in HLA-DR4 type I (insulin-dependent) diabetic patients. Data presented in this article indicate that this association only occurs in heterozygous DR3/4 patients and not in DR1/4 patients. Because there is an interactive effect of both DR3/4 and DR1/4 in type I diabetes, the data indicate that the contribution of DR4 haplotypes varies depending on the haplotype borne on the homologous chromosome. In addition, the frequency of the B44-DR4 haplotype was shown to be decreased in DQw3 (TA10-) diabetic subjects who were DR3/4 compared with those who were DR1/4 or DR4/x (a pooled group of patients with different DR alleles). This finding suggests that the decrease in the B44-DR4 haplotype in type I diabetes is not solely dependent on its linkage disequilibrium with the DQw3 (TA10+) allele but suggests there is an additional effect exerted independently.


Assuntos
Diabetes Mellitus Tipo 1/imunologia , Antígenos HLA-D/análise , Antígenos HLA-DQ/análise , Antígenos HLA-DR/análise , Alelos , Linfócitos B/imunologia , Diabetes Mellitus Tipo 1/genética , Antígenos HLA-DR/genética , Antígeno HLA-DR1 , Antígeno HLA-DR3 , Antígeno HLA-DR4 , Haplótipos , Heterozigoto , Humanos
15.
Diabetes ; 39(1): 96-103, 1990 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-2210066

RESUMO

The analysis of HLA-DQ beta nucleotide sequence polymorphism in insulin-dependent diabetes mellitus (IDDM) patients and control subjects suggests a role for the DQ beta-chain in genetic susceptibility. Sequence determination and oligonucleotide hybridization was carried out on enzymatically amplified DNA from various HLA-DR-typed individuals, including the rare class of DR2+ patients. In the analysis of DQ beta variation in DR4, DRw6, and DR2 haplotypes, a correlation was observed between the presence of the negatively charged residue Asp at position 57 and low susceptibility and the presence of an Ala (DR4), Val (DRw6), or Ser (DR2) and higher susceptibility. However, important exceptions to this pattern have been identified in the analysis of heterozygous DR1/4 IDDM patients. In these individuals, susceptibility appears to correlate with specific DR beta l alleles (Dw4) on the DR4 haplotype, rather than with the DQ beta allele (DQB3.2) that contains Ala at position 57. The DQ beta alleles found in some Chinese IDDM patients also proved discordant with the position-57 correlations. Thus, although there is a general correlation between the residue at position 57 of the DQ beta-chain and IDDM susceptibility, these data do not support the notion that Asp 57 confers complete resistance or protection to IDDM. In general, these results suggest that IDDM susceptibility is conferred by specific combinations of DQ beta and DR beta sequences.


Assuntos
DNA/genética , Diabetes Mellitus Tipo 1/genética , Antígenos HLA-DQ/genética , Polimorfismo Genético/genética , Alelos , Sequência de Aminoácidos , Sequência de Bases , Mapeamento Cromossômico , Eletroforese em Gel de Poliacrilamida , Predisposição Genética para Doença , Cadeias beta de HLA-DQ , Antígeno HLA-DR4/genética , Haplótipos/genética , Humanos , Dados de Sequência Molecular , Testes de Precipitina
16.
Diabetes ; 40(9): 1128-33, 1991 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-1936620

RESUMO

A simple, direct assay for T-lymphocyte reactivity to islet antigen(s) in human insulin-dependent diabetes mellitus (IDDM) should facilitate preclinical diagnosis and the evaluation of intervention therapy to avert autoimmune-mediated beta-cell destruction. In subjects with preclinical or clinical IDDM, we measured the reactivity of peripheral blood mononuclear cells (PBMCs) incubated over 6 days with either adult human islets or fetal pig proislets, or other fetal pig tissues, and with human insulin. With islets, the stimulation index (SI) of [3H]thymidine uptake by PBMCs exceeded the mean + 2SD of control subjects in 6 of 6 preclinical subjects (SI 8.7 +/- 3.7), 7 of 11 clinical subjects (SI 5.2 +/- 3.4), and 1 of 12 control subjects (SI 2.7 +/- 1.7); with insulin, the responses were less in frequency and magnitude, being 4 of 6 (2.7 +/- 1.6), 3 of 11 (2.2 +/- 1.1), and 0 of 12 (1.20 +/- 0.55), respectively. The mean responses to islets of PBMCs from preclinical and clinical subjects differed significantly from control subjects (P less than 0.02 by 2-tailed Kruskal-Wallis test). Secretion of granulocyte macrophage colony-stimulating factor by PBMCs over 6 days was assayed in the preclinical group and generally paralleled the uptake of [3H]thymidine. PBMC reactivity to islets appeared to be at least as sensitive a marker of preclinical IDDM as autoantibodies to a 64,000-Mr protein, presumably the enzyme glutamic acid decarboxylase, in fetal pig proislets. In conclusion, islet-reactive T lymphocytes in subjects with preclinical and clinical IDDM can be identified in bulk culture of PBMCs.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Diabetes Mellitus Tipo 1/imunologia , Ilhotas Pancreáticas/imunologia , Ativação Linfocitária , Estado Pré-Diabético/imunologia , Linfócitos T/imunologia , Adolescente , Adulto , Idoso , Animais , Autoanticorpos/análise , Autoanticorpos/imunologia , Criança , Replicação do DNA , Feminino , Feto , Glutamato Descarboxilase/imunologia , Fator Estimulador de Colônias de Granulócitos e Macrófagos/metabolismo , Antígenos HLA-DR/análise , Humanos , Insulina/farmacologia , Ilhotas Pancreáticas/embriologia , Masculino , Valores de Referência , Suínos , Timidina/metabolismo
17.
Diabetes ; 48(11): 2145-9, 1999 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-10535447

RESUMO

The hypothesis that early exposure to cow's milk or lack of breast-feeding predisposes to type 1 diabetes remains controversial. We aimed to determine prospectively the relationship of, first, duration of exclusive breast-feeding and total duration of breast-feeding, and second, introduction of cow's milk protein as infant formula, cow's milk, or dairy products, to the development of islet antibodies in early life. Some 317 children with a first-degree relative with type 1 diabetes were followed prospectively from birth for 29 months (4-73). Mothers kept a home diary and answered infant feeding questionnaires at 6-month intervals. No systematic feeding advice was given. Insulin autoantibodies (normal range <5.5%), anti-GAD antibodies (<5.0 U), and anti-IA2 antibodies (<3.0 U) were measured at 6-month intervals. Cox proportional hazards model of survival analysis detected no significant difference between children who did not develop islet antibodies (225 of 317 [71%]), children with one islet antibody raised once (52 of 317 [16.4%]), children with one antibody raised repeatedly (18 of 317 [5.7%]), or children with two or more antibodies raised (22 of 317 [6.9%]), in terms of duration of exclusive breast-feeding, total duration of breast-feeding, or introduction of cow's milk-based infant formulas, cow's milk, or dairy products (relative risk: 0.91-1.09). Four of the children with two or more islet antibodies developed type 1 diabetes. We conclude that there is no prospective association between duration of breast-feeding or introduction of cow's milk and the development of islet autoimmunity in high-risk children.


Assuntos
Autoanticorpos/sangue , Aleitamento Materno , Diabetes Mellitus Tipo 1/genética , Diabetes Mellitus Tipo 1/imunologia , Glutamato Descarboxilase/imunologia , Ilhotas Pancreáticas/imunologia , Leite , Envelhecimento , Animais , Bovinos , Feminino , Sangue Fetal/imunologia , Antígenos HLA , Teste de Histocompatibilidade , Humanos , Alimentos Infantis , Recém-Nascido , Estudos Longitudinais , Masculino , Fatores de Tempo
18.
Diabetes ; 49(8): 1319-24, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10923632

RESUMO

Pancreatic islet autoimmunity leading to type 1 diabetes could be triggered by viruses in genetically susceptible individuals. Rotavirus (RV), the most common cause of childhood gastroenteritis, contains peptide sequences highly similar to T-cell epitopes in the islet autoantigens GAD and tyrosine phosphatase IA-2 (IA-2), suggesting T-cells to RV could trigger islet autoimmunity by molecular mimicry. We therefore sought an association between RV infection and islet autoantibody markers in children at risk for diabetes who were followed from birth. There was a specific and highly significant association between RV seroconversion and increases in any of these antibodies: 86% of antibodies to IA-2, 62% to insulin, and 50% to GAD first appeared or increased with increases in RV IgG or IgA. RV infection may therefore trigger or exacerbate islet autoimmunity in genetically susceptible children.


Assuntos
Autoanticorpos/sangue , Diabetes Mellitus Tipo 1/epidemiologia , Ilhotas Pancreáticas/imunologia , Infecções por Rotavirus/epidemiologia , Antígenos Virais/imunologia , Austrália/epidemiologia , Autoantígenos , Autoimunidade , Diabetes Mellitus Tipo 1/imunologia , Gastroenterite/complicações , Gastroenterite/epidemiologia , Gastroenterite/virologia , Glutamato Descarboxilase/imunologia , Humanos , Recém-Nascido , Anticorpos Anti-Insulina/sangue , Estudos Longitudinais , Proteínas de Membrana/imunologia , Mimetismo Molecular , Razão de Chances , Proteína Tirosina Fosfatase não Receptora Tipo 1 , Proteínas Tirosina Fosfatases/imunologia , Proteínas Tirosina Fosfatases Classe 8 Semelhantes a Receptores , Fatores de Risco , Rotavirus/imunologia , Infecções por Rotavirus/complicações
19.
J Med Chem ; 26(8): 1131-7, 1983 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-6876081

RESUMO

The bridging groups O, S, CH2CH2, and SCH2 were used to produce a series of 26 tricyclic triarylethylenes. Their in vitro binding to rat uterine estrogen receptor was measured in a competitive binding assay. Antifertility and uterotrophic tests in rats showed that antiestrogenic activity was present. The most interesting series had a basic side chain, and the most potent compounds were 3-[2-(dimethylamino)ethoxy] -10-ethyl-11-(4-hydroxyphenyl)dibenzo[b,f]thiepin (7b) and 3-[2-(dimethylamino)ethoxy]-11-ethyl-12-(4-hydroxyphenyl)-5,6-dihydrodibenzo[a,e]-cyclooctene (7c), which had good binding (approximately 50% relative to estradiol) and good antiestrogenic activity (ca. one-half of the potency of tamoxifen, III). In this series, the O-bridged compound was the least active, and this is interpreted in terms of the flatness of the dibenzoxepin ring system. Sedative activity was found in some of the compounds.


Assuntos
Dibenzotiepinas/síntese química , Antagonistas de Estrogênios/síntese química , Compostos Heterocíclicos/síntese química , Compostos Policíclicos/síntese química , Animais , Dibenzotiepinas/metabolismo , Antagonistas de Estrogênios/metabolismo , Feminino , Compostos Heterocíclicos/metabolismo , Compostos Policíclicos/metabolismo , Ratos , Receptores de Estrogênio/metabolismo , Útero/metabolismo
20.
J Med Chem ; 37(17): 2664-77, 1994 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-8064795

RESUMO

HIV-1 protease has been identified as a significant target enzyme in AIDS research. While numerous peptide-derived inhibitors have been described, the identification of a nonpeptide inhibitor remains an important goal. Using an HIV-1 protease mass screening technique, 4-hydroxy-3-(3-phenoxypropyl)-2H-1-benzopyran-2-one (1) was identified as a nonpeptide competitive inhibitor of the enzyme. Employing a Monte Carlo-based docking procedure, the coumarin was docked in the active site of the enzyme, revealing a binding mode that was later confirmed by the X-ray crystal analysis. Several analogs were prepared to test the binding interactions and improve the overall binding affinity. The most active compound in the study was 4,7-dihydroxy-3-[4-(2-methoxyphenyl)butyl]-2H-1-benzopyran-2-one (31).


Assuntos
4-Hidroxicumarinas/química , Cumarínicos/química , Inibidores da Protease de HIV/química , Protease de HIV/química , 4-Hidroxicumarinas/metabolismo , Síndrome da Imunodeficiência Adquirida/tratamento farmacológico , Sítios de Ligação , Cumarínicos/síntese química , Cumarínicos/metabolismo , Cristalografia por Raios X , Desenho de Fármacos , Protease de HIV/metabolismo , Inibidores da Protease de HIV/metabolismo , HIV-1/enzimologia , Humanos , Modelos Moleculares , Conformação Molecular , Estrutura Molecular , Método de Monte Carlo , Oligopeptídeos/química , Oligopeptídeos/metabolismo , Conformação Proteica
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