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1.
Int Endod J ; 47(1): 32-40, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23647356

RESUMEN

AIM: To quantify bacterial equivalents before and after chemomechanical preparation using 3% sodium hypochlorite (NaOCl) and intracanal dressing with calcium hydroxide paste (Ca(OH)2 ) or 2% Chlorhexidine digluconate gel (CHX) in necrotic pulps associated or not with apical periodontitis and to further compare this quantification with counts of anaerobic microorganisms. METHODOLOGY: Prospective clinical trial in 69 single-rooted adult teeth (strict inclusion criteria); CHX group: 34; Ca(OH)2 group: 35. Bacteria samples were taken at baseline (S1), after chemomechanical preparation (S2) and after 14 days of intracanal dressing (S3). Bacterial equivalents were assessed by broad-range real-time polymerase chain reaction (qPCR), and live viable bacteria measured with conventional anaerobic culture (CFU/mL). Descriptive/inferential analysis was performed with spss vs. 20.0 (α = 0.05) using the Kruskal-Wallis, Mann-Whitney and chi-squared tests and Spearman's correlation coefficients. RESULTS: Both groups showed a significant decrease between S1 and S2 (Mann-Whitney U-test; P < 0.001) both in qPCR and in culture. In the Ca(OH)2 -group, no variation was observed between S2 and S3 by qPCR and culture. In contrast, the CHX group showed a significant increase from S2 to S3 by both techniques. The two groups were only significantly different in S3 (Mann-Whitney U-test; P ≤ 0.001), with a worse performance in the CHX group. Again, these results were congruent by both approaches. Data from both approaches correlate reasonably (rS < 0.5). CONCLUSIONS: Infected root canals contained a high bacterial load, and the chemomechanical root canal preparation reduced bacterial equivalents by 99.1% and anaerobic counts by 98.5%. Intracanal dressings were not efficient at reducing bacterial load, but the 14-day intracanal dressing with Ca(OH)2 performed significantly better than CHX, particularly in cases with apical periodontitis.


Asunto(s)
Bacterias Anaerobias/aislamiento & purificación , Vendajes , Cavidad Pulpar/microbiología , Tratamiento del Conducto Radicular , Adulto , Bacterias Anaerobias/genética , Recuento de Colonia Microbiana , ADN Ribosómico/genética , Humanos , Portugal , Estudios Prospectivos , ARN Ribosómico 16S/genética , Reacción en Cadena en Tiempo Real de la Polimerasa
2.
J Clin Microbiol ; 45(9): 2881-8, 2007 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-17626175

RESUMEN

Two hundred eighty methicillin-resistant Staphylococcus aureus (MRSA) clinical isolates recovered from a tertiary care hospital in Oporto, Portugal, between 2003 and 2005 were studied by a combination of molecular typing techniques in order to investigate the genetic backgrounds associated with the changes in the resistance phenotypes observed since 2001 and compare them to those previously found in the hospital. All MRSA isolates were grouped into resistance profiles for a panel of seven antibiotics and characterized by pulsed-field gel electrophoresis (PFGE) and SCCmec (staphylococcal cassette chromosome mec) typing. Representative isolates of PFGE types were further studied by spa typing and multilocus sequence typing. Our findings clearly document that the increasing isolation of nonmultiresistant MRSA strains was associated with the decline (from 69% in 1996 to 2000 to 12% in 2003 to 2005) and massive replacement of the multiresistant Brazilian clone (ST239-IIIA) by the epidemic EMRSA-15 clone (ST22-IV), in which resistance to antibiotics other than beta-lactams is very rare, as the major clone (80% of isolates). The Iberian clone (ST247-IA), a major clone in 1992 to 1993, was represented in the present study by just one isolate. Two other pandemic MRSA clones were detected, as sporadic isolates, for the first time in our hospital: the New York/Japan (ST5-II) and the EMRSA-16 (ST36-II) clones. Furthermore, the pattern of susceptibility of MRSA isolates both to gentamicin and to trimethoprim-sulfamethoxazole was shown to be an excellent phenotypic marker for the discrimination of the EMRSA-15 clone from other nonmultiresistant MRSA clones present in our hospital.


Asunto(s)
Antibacterianos/farmacología , Resistencia a la Meticilina , Infecciones Estafilocócicas/epidemiología , Infecciones Estafilocócicas/microbiología , Staphylococcus aureus/clasificación , Staphylococcus aureus/efectos de los fármacos , Técnicas de Tipificación Bacteriana , Células Clonales , Infección Hospitalaria/epidemiología , Infección Hospitalaria/microbiología , ADN Bacteriano/genética , Resistencia a Medicamentos , Electroforesis en Gel de Campo Pulsado , Genotipo , Hospitales , Humanos , Pruebas de Sensibilidad Microbiana , Epidemiología Molecular , Portugal/epidemiología , Análisis de Secuencia de ADN , Proteína Estafilocócica A/genética , Staphylococcus aureus/genética , Staphylococcus aureus/aislamiento & purificación
3.
Int Braz J Urol ; 32(3): 330-4; discussion 335, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16813680

RESUMEN

PURPOSE: We examined the significance of the CAG repeat polymorphism in the pathogenesis of cryptorchidism. MATERIALS AND METHODS: Genomic deoxyribonucleic acid (DNA) was extracted from blood samples from 42 cryptorchid boys and from 31 non-cryptorchid control subjects. In the cryptorchid group, 7 had bilateral cryptorchidism and 6 had patent processus vaginalis in the contralateral side. To determine the number of CAG repeats, the DNA was amplified by polymerase chain reaction and sequenced. RESULTS: The mean CAG repeat length in the AR gene was 22.5 (range 16 to 28) in patients and 21.5 (range 17 to 26) in controls (non-significant). Patients with bilateral cryptorchidism had a mean length of 24.3 (range 21 to 26) and patients with unilateral cryptorchidism and patent processus vaginalis in the contra lateral side had a mean of 25.2 (range 21 to 28), which was statistically different from controls (p = 0.015 and p = 0.005 respectively). CONCLUSION: CAG repeat length of the AR gene does not seem to play a major role in patients with unilateral cryptorchidism. However, in patients with bilateral undescended testis, a less functional androgen receptor through a longer polyglutamine chain may have a role in its pathogenesis. In the same way, patients with unilateral cryptorchidism a contralateral patent processus vaginalis have longer CAG repeats that might be responsible for a slower testicular descent and incomplete closure of the processus vaginalis.


Asunto(s)
Criptorquidismo/genética , Polimorfismo Genético/genética , Receptores Androgénicos/genética , Repeticiones de Trinucleótidos/genética , Adolescente , Anciano , Estudios de Casos y Controles , Niño , Preescolar , Genotipo , Humanos , Masculino , Reacción en Cadena de la Polimerasa , Estudios Prospectivos
4.
Int. braz. j. urol ; 32(3): 330-335, May-June 2006. tab
Artículo en Inglés | LILACS | ID: lil-433382

RESUMEN

PURPOSE: We examined the significance of the CAG repeat polymorphism in the pathogenesis of cryptorchidism. MATERIALS AND METHODS: Genomic deoxyribonucleic acid (DNA) was extracted from blood samples from 42 cryptorchid boys and from 31 non-cryptorchid control subjects. In the cryptorchid group, 7 had bilateral cryptorchidism and 6 had patent processus vaginalis in the contralateral side. To determine the number of CAG repeats, the DNA was amplified by polymerase chain reaction and sequenced. RESULTS: The mean CAG repeat length in the AR gene was 22.5 (range 16 to 28) in patients and 21.5 (range 17 to 26) in controls (non-significant). Patients with bilateral cryptorchidism had a mean length of 24.3 (range 21 to 26) and patients with unilateral cryptorchidism and patent processus vaginalis in the contra lateral side had a mean of 25.2 (range 21 to 28), which was statistically different from controls (p = 0.015 and p = 0.005 respectively). CONCLUSION: CAG repeat length of the AR gene does not seem to play a major role in patients with unilateral cryptorchidism. However, in patients with bilateral undescended testis, a less functional androgen receptor through a longer polyglutamine chain may have a role in its pathogenesis. In the same way, patients with unilateral cryptorchidism a contralateral patent processus vaginalis have longer CAG repeats that might be responsible for a slower testicular descent and incomplete closure of the processus vaginalis.


Asunto(s)
Adolescente , Anciano , Niño , Preescolar , Humanos , Masculino , Criptorquidismo/genética , Polimorfismo Genético/genética , Receptores Androgénicos/genética , Repeticiones de Trinucleótidos/genética , Estudios de Casos y Controles , Genotipo , Reacción en Cadena de la Polimerasa , Estudios Prospectivos
5.
Eur J Haematol ; 74(5): 374-80, 2005 May.
Artículo en Inglés | MEDLINE | ID: mdl-15813910

RESUMEN

Vertical and horizontal interactions between membrane constituents account for integrity, strength and deformability of the erythrocyte. Disruption of vertical interactions caused by membrane protein deficiencies in hereditary spherocytosis (HS), favor membrane vesiculation with development of spherocytic cells. Our aim was to evaluate the hematological and clinical presentation of HS according to the type and amount of protein deficiency. We studied 81 Portuguese individuals, 71 belonging to 21 families plus 10 unrelated subjects, and found that 51 of them were HS patients. Patients were classified as presenting mild, typical or severe HS, according to laboratory results and clinical follow-up. We performed screening tests and the standardized electrophoretic membrane protein analysis to identify and quantify protein deficiencies. We found band 3 and ankyrin deficiencies as the major causes for HS. The ratios between the value of the primary and/or secondary protein deficiencies showed significantly different values according to the severity of HS, and a significant inverse correlation with the severity of HS was observed. In mild HS, the ratios between protein deficiencies reflected equivalent protein deficiencies, while an unbalance was observed in typical HS, which was enhanced in severe HS. Our data suggest that the relative quantification of each major membrane protein and of the ratios between the values of protein deficiencies may be helpful in providing additional data about the clinical outcome of HS.


Asunto(s)
Proteína 1 de Intercambio de Anión de Eritrocito/deficiencia , Ancirinas/deficiencia , Proteínas de la Membrana/sangre , Proteínas de la Membrana/deficiencia , Esferocitosis Hereditaria/terapia , Membrana Eritrocítica/química , Humanos , Portugal , Valor Predictivo de las Pruebas , Esferocitosis Hereditaria/sangre , Resultado del Tratamiento
6.
Clin Lab Haematol ; 26(4): 297-300, 2004 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-15279669

RESUMEN

The authors report the case of a 9-year-old Caucasian girl, born in northern Portugal, with chronic nonspherocytic haemolytic anaemia and without family history of anaemia. The aethiological study of this anaemia revealed pyruvate kinase deficiency (PKD), because of two previously described mutations (426Arg-->Trp and 510Arg-->Gln). Since the blood smear revealed features not fully compatible with PKD diagnosis, additional tests were performed for the propositus and her parents, namely red blood cell membrane protein analysis. A decrease in proteins band 3 (15%) and 4.2 (18%) was found in the propositus. Her father presented only a decrease in band 3 (11%). Coexistence of PKD and erythrocyte membrane proteins deficiency in the same patient is very uncommon. Our findings suggest that a careful blood smear observation may lead to the identification of a combined deficiency in erythrocyte membrane proteins and enzymopathies.


Asunto(s)
Anemia Hemolítica Congénita/etiología , Proteína 1 de Intercambio de Anión de Eritrocito/deficiencia , Eritrocitos/metabolismo , Piruvato Quinasa/deficiencia , Errores Innatos del Metabolismo del Piruvato/complicaciones , Anemia Hemolítica Congénita/genética , Anemia Hemolítica Congénita/metabolismo , Proteína 1 de Intercambio de Anión de Eritrocito/genética , Proteína 1 de Intercambio de Anión de Eritrocito/metabolismo , Niño , Análisis Mutacional de ADN , Eritrocitos/enzimología , Exones , Salud de la Familia , Femenino , Pruebas Hematológicas , Heterocigoto , Humanos , Mutación Puntual , Piruvato Quinasa/genética , Piruvato Quinasa/metabolismo , Errores Innatos del Metabolismo del Piruvato/genética , Errores Innatos del Metabolismo del Piruvato/metabolismo
7.
Microb Drug Resist ; 8(4): 301-9, 2002.
Artículo en Inglés | MEDLINE | ID: mdl-12523627

RESUMEN

Methicillin-resistant Staphylococcus aureus (MRSA) isolates recovered from a general hospital in Oporto, Portugal, during two periods (1992-1993 and 1996-2000) were characterized by pulsed-field gel electrophoresis (PFGE) of SmaI fragments, and by hybridization of ClaI digests with mecA and Tn554 probes, discriminating the isolates in mecA::Tn554::PFGE genotypes. In addition, a representative sample of the defined genotypes was characterized by multilocus sequence typing (MLST) and SCCmec (staphylococcal cassette chromosome mec) typing, generating the corresponding ST-SCCmec types. In 1992-1993, 77% of MRSA belonged to the Iberian clone (genotype I::E::A or ST247-IA). In 1996-2000, the frequency of this clone decreased to 19% and the majority (69%) of the isolates belonged to another international clone, the Brazilian MRSA (genotype XI::B::B or ST239-IIIA). Trimethoprim/sulfamethoxazole (SXT) was confirmed to be an important phenotypic marker to distinguish the Iberian (SXT-susceptible) and the Brazilian (SXT-resistant) clones in MRSA isolates from Portugal. Our observations document major shifts in the dominant MRSA clonal types that occurred in this hospital since 1992, suggesting a selective advantage of the Brazilian relatively to the Iberian clone. In addition to these two MRSA clones that are the most frequent in Portuguese hospitals since the early 1990s, sporadic MRSA clones (representing 14% of the total) were identified and characterized.


Asunto(s)
Infección Hospitalaria/microbiología , Resistencia a la Meticilina , Infecciones Estafilocócicas/microbiología , Staphylococcus aureus/efectos de los fármacos , Antibacterianos/farmacología , Infección Hospitalaria/epidemiología , Resistencia a Medicamentos , Electroforesis en Gel de Campo Pulsado , Genotipo , Humanos , Hibridación in Situ , Fenotipo , Portugal/epidemiología , Infecciones Estafilocócicas/epidemiología , Factores de Tiempo , Combinación Trimetoprim y Sulfametoxazol/farmacología
8.
BMC Infect Dis ; 1: 2, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11389774

RESUMEN

BACKGROUND: CMV is a major clinical problem in transplant recipients. Thus, it is important to use sensitive and specific diagnostic techniques to rapidly and accurately detect CMV infection and identify patients at risk of developing CMV disease. In the present study, CMV infection after liver transplantation was monitored retrospectively by two molecular biology assays - a quantitative PCR assay and a qualitative NASBA assay. The results were compared with those obtained by prospective pp65 antigenemia determinations. MATERIALS AND METHODS: 87 consecutive samples from 10 liver transplanted patients were tested for CMV by pp65 antigenemia, and CMV monitor and NASBA pp67 mRNA assay. RESULTS: CMV infection was detected in all patients by antigenemia and CMV monitor, whereas NASBA assay identified only 8/10 patients with viremia. Furthermore, CMV infection was never detected earlier by molecular biology assays than by antigenemia. Only 5/10 patients with CMV infection developed CMV disease. Using a cut off value of 8 cells/50,000, antigenemia was found to be the assay that better identified patients at risk of developing CMV disease. However, the kinetics of the onset of infection detected by NASBA and CMV monitor seemed to have better identified patients at risk of developing CMV disease. Furthermore, before onset of disease, CMV pp67 mRNA was found to have similar or better negative and positive predictive values for the development of CMV disease. CONCLUSIONS: The present data, suggests that the concomitant use of antigenemia and pp67 mRNA assay gives the best identification of patients at risk of developing CMV disease.


Asunto(s)
Infecciones por Citomegalovirus/diagnóstico , Trasplante de Hígado/efectos adversos , Fosfoproteínas/análisis , Complicaciones Posoperatorias/diagnóstico , Proteínas de la Matriz Viral/análisis , Adulto , Antígenos Virales , Citomegalovirus/genética , Citomegalovirus/aislamiento & purificación , Infecciones por Citomegalovirus/epidemiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Fosfoproteínas/genética , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/virología , ARN Mensajero/análisis , Estadística como Asunto , Proteínas de la Matriz Viral/genética
9.
Alcohol Clin Exp Res ; 24(4): 519-27, 2000 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-10798589

RESUMEN

BACKGROUND: Despite heavy alcohol consumption, only a low percentage of heavy drinkers develop liver disease. Imbalances in T-cell subsets and iron metabolism parameters are common findings in heavy drinkers, yet the possible role played by discrete T-lymphocyte subsets under heavy alcohol consumption remains unclear. METHODS: To gain new insights into the possible role played by T lymphocytes during alcohol consumption, characterization of CD28 expression and TcR repertoire in peripheral blood CD4+ and CD8+ T cells by two and three-color flow cytometry was performed. A group of heavy alcohol drinkers (AHD, n = 71) and a group of age-matched controls (n = 81), both HLA-phenotyped and HFE-genotyped, constituted the groups under study. RESULTS: Marked expansions of CD28- T cells within the CD8+ but not the CD4+ T-cell pool were observed in AHD compared with controls. These CD8+CD28- expansions were paralleled by expansions of CD8+ T cells bearing specific TcR Valpha/beta chains, namely VP5.2. Moreover, AHD, but not controls, carrying the H63D mutation in the HFE gene showed significantly higher percentages of CD28- T cells within the CD8+ T-cell pool than AHD carrying the normal HFE gene. Finally, high numbers of CD8+CD28- T cells in AHD were associated with lower levels of the liver-related enzymes ALT and GGT. CONCLUSIONS: This study showed that under active ethanol consumption, expansions of discrete CD8+ T-cell subsets occur within the CD8+ T-cell pool, that molecules of the MHC-class I locus seem to influence the extent of the expansions, and that high numbers of CD8+CD28- T cells are associated with low levels of liver enzymes in AHD.


Asunto(s)
Alcoholismo/sangre , Antígenos CD28/metabolismo , Linfocitos T CD8-positivos/metabolismo , Subgrupos de Linfocitos T/metabolismo , Adulto , Anciano , Análisis de Varianza , Biomarcadores , Femenino , Humanos , Masculino , Persona de Mediana Edad
10.
Blood ; 95(4): 1499-501, 2000 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-10666231

RESUMEN

Glucose-6-phosphate dehydrogenase (G6PD) deficiency is a common X-linked enzyme abnormality. The clinical phenotype is variable but often predictable from the molecular lesion. Class I variants (the most severe forms of the disease) cluster within exon 10, in a region that, at the protein level, is believed to be involved in dimerization. Here we describe a de novo mutation (C269Y) of a new class I variant (G6PD Aveiro) that maps to exon 8. Mutant and normal alleles were found in both hematopoietic and buccal cells, indicating the presence of mosaicism. The available model of the protein predicts that this lesion lies in proximity to the dimer interface of the molecule. A possible mechanism to explain the severity of the defect is proposed. (Blood. 2000;95:1499-1501)


Asunto(s)
Anemia Hemolítica Congénita no Esferocítica/genética , Glucosafosfato Deshidrogenasa/genética , Mutación Puntual , Sustitución de Aminoácidos , Anemia Hemolítica Congénita no Esferocítica/enzimología , Preescolar , Femenino , Variación Genética , Impresión Genómica , Glucosafosfato Deshidrogenasa/metabolismo , Humanos , Masculino
11.
Blood Cells Mol Dis ; 25(2): 130-8, 1999 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-10389595

RESUMEN

The major elements of bone pathology in Gaucher disease are a failure of osteoclast and osteoblast function, resulting in osteopenia and also osteonecrosis. T lymphocytes have recently been found to be involved in the regulation of osteoblast/osteoclast activity in vitro. In the present report the peripheral blood T major lymphocyte subsets were investigated in a group of genotyped type 1 Gaucher disease patients. A total of 31 patients were studied: 21 non-splenectomized (5 N370S homozygotes) and 10 splenectomized (of whom 1 was a N370S homozygote). The results show that non-splenectomized patients present a decrease in absolute numbers of peripheral blood T lymphocytes, specially the CD4+ T subset. However, when patients were analyzed with respect to the presence of bone disease, the number of CD8+ T lymphocytes was found to be statistically significantly lower in patients presenting bone involvement. Furthermore, lower numbers of CD8+ T lymphocytes were significantly correlated with higher levels of plasma tartrate resistant acid phosphatase (TRAP) activity, a putative marker of osteoclast cell activity. These in vivo findings are in agreement with the results reached in vitro by others. They provide an additional marker of disease severity in Gaucher disease. In the group of genotyped Gaucher disease patients, the majority of the N370S homozygous patients presented a clinically milder phenotype, including the absence of bone involvement, confirming earlier reports predicting that a number of these patients may remain undiagnosed. Collectively the homozygosity for the N370S mutation and normal T cell numbers may provide additional markers for the clinical heterogeneity of Gaucher disease.


Asunto(s)
Enfermedades Óseas/sangre , Enfermedad de Gaucher/sangre , Linfocitos T/citología , Fosfatasa Ácida/sangre , Fosfatasa Ácida/efectos de los fármacos , Adolescente , Adulto , Linfocitos T CD4-Positivos/citología , Linfocitos T CD8-positivos/citología , Niño , Femenino , Enfermedad de Gaucher/tratamiento farmacológico , Enfermedad de Gaucher/genética , Genotipo , Glucosilceramidasa/uso terapéutico , Humanos , Isoenzimas/sangre , Isoenzimas/efectos de los fármacos , Recuento de Linfocitos/efectos de los fármacos , Masculino , Persona de Mediana Edad , Proteínas Recombinantes/uso terapéutico , Esplenectomía , Fosfatasa Ácida Tartratorresistente
12.
Br J Haematol ; 105(1): 68-74, 1999 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-10233364

RESUMEN

We characterized the genetic nature of beta-thalassaemia in northern Portugal. Of the 164 patients studied three were beta-thalassaemia major cases (one IVS-1-6/beta degrees 39 and two homozygous IVS-1-110). The analysis of the frequency of each mutation in the families revealed that the codon 6(-A) mutation was unexpectedly frequent (40%) and associated with the beta-globin haplotype E, and not with the usual European and North African CD6(-A) haplotypes. In contrast, the frequency of IVS-1-6 (8%) and beta degrees 39 (19%) was found to be lower than in the rest of the country. The frequency of all other mutations was similar to previous reports for central/southern Portugal. Six families carried none of the most frequent mutations in the Mediterranean area. These families were studied by gene sequencing, revealing that three families carried a previously described mutation (CD16 G --> A). The remaining families carried previously unidentified mutations: one showed an 86 bp insertion in exon 2 (named HGSA) and two showed a deletion of a cytidine in codon 11 (CD11(-C)). The results, showing a high frequency (82%) of beta degrees mutations, strongly indicates that genetic counselling should be intensified as a means of preventing the spread of the severe mutations found.


Asunto(s)
Globinas/genética , Mutación/genética , Talasemia beta/epidemiología , Adolescente , Adulto , Secuencia de Bases , Femenino , Frecuencia de los Genes , Pruebas Genéticas , Haplotipos , Humanos , Masculino , Persona de Mediana Edad , Datos de Secuencia Molecular , Portugal/epidemiología , Análisis de Secuencia , Talasemia beta/genética
13.
Acta Med Port ; 12(7-11): 283-6, 1999.
Artículo en Portugués | MEDLINE | ID: mdl-10707466

RESUMEN

Glucose-6-phosphate dehydrogenase (G6PD) deficiency is the most common erythrocyte enzymopathy, affecting over 400 million people worldwide. Portugal is a low prevalence country, but immigrants from endemic regions are common, particularly in the south of the country. In the present study, we report the laboratory findings observed in two black proband children with low G6PD enzyme activity (23 and 18%). The study also included their first-degree relatives. Both biochemical parameters (enzyme activity, electrophoretic mobility and cytochemical test) and genetic determinations (mutation and haplotype characterisation) were performed.


Asunto(s)
Deficiencia de Glucosafosfato Deshidrogenasa/diagnóstico , Secuencia de Bases , Cartilla de ADN , República Democrática del Congo/etnología , Femenino , Glucosafosfato Deshidrogenasa/genética , Deficiencia de Glucosafosfato Deshidrogenasa/enzimología , Deficiencia de Glucosafosfato Deshidrogenasa/etnología , Deficiencia de Glucosafosfato Deshidrogenasa/genética , Haplotipos , Humanos , Lactante , Datos de Secuencia Molecular , Mutación/genética , Portugal , Sudáfrica/etnología
14.
Br J Haematol ; 103(3): 842-5, 1998 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-9858243

RESUMEN

Mutation analysis was performed for two HFE mutations (C282Y, H63D) in unrelated patients with hereditary haemochromatosis (n = 92), family members of patients (n = 34), and unrelated controls (n = 157) from Northern Germany, 87/92 patients (94.6%) revealed the C282Y mutation in homozygous form, five were heterozygous. No H63D mutation was found in 174 chromosomes of patients homozygous for C282Y, whereas four of the heterozygote patients also carried the H63D mutation. Among the control group, 9.6% were heterozygotes for C282Y. 2/157 subjects were homozygous, 37/157 were heterozygous for the H63D mutation, but showed no signs of iron overload.


Asunto(s)
Cromosomas Humanos Par 6/genética , Hemocromatosis/genética , Mutación , Adulto , Femenino , Alemania/epidemiología , Hemocromatosis/epidemiología , Hemocromatosis/metabolismo , Heterocigoto , Homocigoto , Humanos , Hierro/metabolismo , Masculino , Persona de Mediana Edad , Linaje , Prevalencia
15.
J Intern Med ; 243(3): 203-8, 1998 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-9627157

RESUMEN

OBJECTIVE: To determine the frequency of mutations (C282Y and H63D) in a newly identified gene HFE in patients with hereditary haemochromatosis (HH) in Sweden. DESIGN: Molecular genetic analyses of the HFE gene (polymerase chain reaction (PCR) followed by enzyme restriction) were performed in genomic DNA from unrelated patients with a clinical diagnosis of HH and in healthy subjects. SETTINGS: Patients with HH treated with phlebotomies at Karolinska Hospital and Huddinge Hospital were analyzed. SUBJECTS: Eighty-seven unrelated patients with HH and 117 healthy controls. RESULTS: It was found that the HFE C282Y mutation occurs in 94.2% of chromosomes from patients with HH. Eighty patients (92.0%) were homozygous for the C282Y mutation and one was heterozygous. Three patients were heterozygous for both C282Y and H63D mutations. One patient was homozygous and one was heterozygous for the H63D mutation. One patient carried normal alleles. In healthy controls, the C282Y mutation occurred in nine subjects (7.7%), all of which were heterozygous. The H63D mutation was found in 28 control subjects, one of which was homozygous. CONCLUSIONS: We found that the majority of patients with HH have the C282Y mutation in the HFE gene. The frequency of the H63D mutation was higher in controls than in patients with HH, although in chromosomes at risk the frequency of the H63D mutation was higher in patients.


Asunto(s)
Genes MHC Clase I , Hemocromatosis/genética , Mutación , Adulto , Anciano , Femenino , Genotipo , Humanos , Masculino , Persona de Mediana Edad , Reacción en Cadena de la Polimerasa , Estudios Seroepidemiológicos , Suecia
16.
Immunogenetics ; 47(5): 404-10, 1998 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-9510559

RESUMEN

The present study is an analysis of the frequencies of HFE mutations in patients with different forms of iron overload compared with the frequencies found in healthy subjects from the same region. The frequencies of HLA-A and -B antigens and HLA haplotypes were also analyzed in the same subjects. The study population included: 71 healthy individuals; 39 genetically and clinically well-characterized patients with genetic hemochromatosis (HH); and 25 patients with non-classical forms of iron overload (NCH), excluding secondary hemochromatosis. All subjects were HLA-typed and HFE-genotyped by the oligonucleotide ligation assay (OLA). The gene frequencies found for the C282Y and H63D mutations of HFE were respectively: 0.03 and 0.23 in healthy individuals, 0.86 and 0.04 in HH patients, and 0.08 and 0.48 in NCH patients. An expected significant association between HH and HLA-A3 was observed, which was found to be in linkage disequilibrium with the C282Y mutation. A new association was seen, however, between HLA-A29 and NCH, in linkage disequilibrium with the H63D mutation. Again as expected, the HLA-B antigen B7 was associated with HH in linkage disequilibrium with HLA-A3. In addition, the HLA-B antigen B44 was found to be associated with NCH but not in linkage disequilibrium with either A29 or the H63D mutation. In conclusion, a new association of the HFE H63D mutation with forms of hemochromatosis other than HH and a new association between the HLA phenotype A29 and the HFE H63D mutation were found in the same patients. These findings reinforce evidence for the involvement of the major histocompatibility class I in iron metabolism, supporting the notion of a physiological role for the immunological system in the regulation of iron load.


Asunto(s)
Antígenos HLA/genética , Antígenos HLA-A/genética , Antígenos HLA-B/genética , Hemocromatosis/genética , Antígenos de Histocompatibilidad Clase I/genética , Sobrecarga de Hierro/genética , Proteínas de la Membrana , Mutación/genética , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Ferritinas/sangre , Frecuencia de los Genes/genética , Ligamiento Genético/genética , Haplotipos/genética , Hemocromatosis/sangre , Hemocromatosis/inmunología , Hemocromatosis/metabolismo , Proteína de la Hemocromatosis , Humanos , Hierro/sangre , Hierro/metabolismo , Sobrecarga de Hierro/sangre , Sobrecarga de Hierro/inmunología , Sobrecarga de Hierro/metabolismo , Masculino , Persona de Mediana Edad , Transferrina/genética , Transferrina/metabolismo
17.
Acta Haematol ; 100(4): 207-10, 1998.
Artículo en Inglés | MEDLINE | ID: mdl-9973645

RESUMEN

This case report details a single patient with pure red cell aplasia (PRCA) associated with clonal CD3+, TCRalphabeta+, TCR-Vbeta8+, CD8+, CD57+ large granular lymphocytosis whose anaemia did not respond to conventional immunosuppressive therapy but did respond to cyclosporin A (CsA). The patient has become dependent on CsA for 7 years in order to control anaemia due to associated PRCA.


Asunto(s)
Linfocitos T CD8-positivos/patología , Linfocitosis/complicaciones , Linfocitosis/patología , Aplasia Pura de Células Rojas/complicaciones , Anciano , Tamaño de la Célula , Células Clonales , Ciclosporina/uso terapéutico , Gránulos Citoplasmáticos , Humanos , Inmunosupresores/uso terapéutico , Masculino , Persona de Mediana Edad , Aplasia Pura de Células Rojas/tratamiento farmacológico , Trastornos Relacionados con Sustancias/sangre
18.
Hepatology ; 25(2): 397-402, 1997 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-9021953

RESUMEN

Hemochromatosis is a hereditary iron-overload disease linked to HLA. The clinical expression of hemochromatosis is influenced by sex and age. However, other factors must account for the notorious heterogeneity of expression of the disease independent of sex, age, and HLA phenotype. The present study attempts to clarify some of these additional factors based on exhaustive statistical analysis of data collected from 43 selected patients with hemochromatosis. The statistical analysis focused on three groups of variables: the first group included variables reflecting the clinical expression of the disease; the second group represented the biochemical and hematological values at the time of diagnosis; and the third group consisted of the independent variables sex, age, HLA phenotype, and T-cell subset profile, i.e., the percentages and total numbers of CD4+ and CD8+ cells and the CD4-CD8 ratios. The results show that the relative expansion of the two main T-cell subsets, in the context of the HLA phenotype, correlates significantly with the clinical expression of hemochromatosis and the severity of iron overload. The present findings substantiate further the postulate that T cells have a role in the regulation of iron metabolism.


Asunto(s)
Relación CD4-CD8 , Antígenos HLA , Hemocromatosis/inmunología , Adulto , Factores de Edad , Anciano , Comorbilidad , Femenino , Hemocromatosis/epidemiología , Hemocromatosis/metabolismo , Humanos , Hierro/metabolismo , Cirrosis Hepática/epidemiología , Masculino , Persona de Mediana Edad , Fenotipo , Factores Sexuales
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