Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 80
Filtrar
Más filtros

Banco de datos
País/Región como asunto
Tipo del documento
Intervalo de año de publicación
1.
Arch Toxicol ; 92(5): 1785-1795, 2018 05.
Artículo en Inglés | MEDLINE | ID: mdl-29523930

RESUMEN

Occupational and environmental asbestos exposure is the main determinant of malignant pleural mesothelioma (MPM), however, the mechanisms by which its fibres contribute to cell toxicity and transformation are not completely clear. Aberrant DNA methylation is a common event in cancer but epigenetic modifications involved specifically in MPM carcinogenesis need to be better clarified. To investigate asbestos-induced DNA methylation and gene expression changes, we treated Met5A mesothelial cells with different concentrations of crocidolite and chrysotile asbestos (0.5 ÷ 5.0 µg/cm2, 72 h incubation). Overall, we observed 243 and 302 differentially methylated CpGs (≥ 10%) between the asbestos dose at 5 µg/cm2 and untreated control, in chrysotile and crocidolite treatment, respectively. To examine the dose-response effect, Spearman's correlation test was performed and significant CpGs located in genes involved in migration/cell adhesion processes were identified in both treatments. Moreover, we found that both crocidolite and chrysotile exposure induced a significant up-regulation of CA9 and SRGN (log2 fold change > 1.5), previously reported as associated with a more aggressive MPM phenotype. However, we found no correlation between methylation and gene expression changes, except for a moderate significant inverse correlation at the promoter region of DKK1 (Spearman rho = - 1, P value = 0.02) after chrysotile exposure. These results describe for the first time the relationship between DNA methylation modifications and asbestos exposure. Our findings provide a basis to further explore and validate asbestos-induced DNA methylation changes, that could influence MPM carcinogenesis and possibly identifying new chemopreventive target.


Asunto(s)
Amianto/toxicidad , Metilación de ADN/efectos de los fármacos , Transcriptoma/efectos de los fármacos , Antígenos de Neoplasias/genética , Amianto/química , Asbesto Crocidolita/administración & dosificación , Asbesto Crocidolita/toxicidad , Asbestos Serpentinas/administración & dosificación , Asbestos Serpentinas/toxicidad , Anhidrasa Carbónica IX/genética , Línea Celular , Relación Dosis-Respuesta a Droga , Células Epiteliales/efectos de los fármacos , Humanos , Neoplasias Pulmonares/inducido químicamente , Neoplasias Pulmonares/genética , Mesotelioma/inducido químicamente , Mesotelioma/genética , Mesotelioma Maligno , Reacción en Cadena en Tiempo Real de la Polimerasa
2.
Genes Immun ; 16(2): 151-61, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25569260

RESUMEN

Lymphocyte apoptosis is mainly induced by either death receptor-dependent activation of caspase-8 or mitochondria-dependent activation of caspase-9. Mutations in caspase-8 lead to autoimmunity/lymphoproliferation and immunodeficiency. This work describes a heterozygous H237P mutation in caspase-9 that can lead to similar disorders. H237P mutation was detected in two patients: Pt1 with autoimmunity/lymphoproliferation, severe hypogammaglobulinemia and Pt2 with mild hypogammaglobulinemia and Burkitt lymphoma. Their lymphocytes displayed defective caspase-9 activity and decreased apoptotic and activation responses. Transfection experiments showed that mutant caspase-9 display defective enzyme and proapoptotic activities and a dominant-negative effect on wild-type caspase-9. Ex vivo analysis of the patients' lymphocytes and in vitro transfection experiments showed that the expression of mutant caspase-9 correlated with a downregulation of BAFFR (B-cell-activating factor belonging to the TNF family (BAFF) receptor) in B cells and ICOS (inducible T-cell costimulator) in T cells. Both patients carried a second inherited heterozygous mutation missing in the relatives carrying H237P: Pt1 in the transmembrane activator and CAML interactor (TACI) gene (S144X) and Pt2 in the perforin (PRF1) gene (N252S). Both mutations have been previously associated with immunodeficiencies in homozygosis or compound heterozygosis. Taken together, these data suggest that caspase-9 mutations may predispose to immunodeficiency by cooperating with other genetic factors, possibly by downregulating the expression of BAFFR and ICOS.


Asunto(s)
Receptor del Factor Activador de Células B/biosíntesis , Caspasa 9/genética , Síndromes de Inmunodeficiencia/genética , Proteína Coestimuladora de Linfocitos T Inducibles/biosíntesis , Trastornos Linfoproliferativos/genética , Mutación , Adolescente , Adulto , Apoptosis/genética , Apoptosis/inmunología , Receptor del Factor Activador de Células B/genética , Receptor del Factor Activador de Células B/inmunología , Caspasa 9/inmunología , Regulación hacia Abajo , Células HEK293 , Humanos , Síndromes de Inmunodeficiencia/inmunología , Síndromes de Inmunodeficiencia/metabolismo , Proteína Coestimuladora de Linfocitos T Inducibles/genética , Proteína Coestimuladora de Linfocitos T Inducibles/inmunología , Trastornos Linfoproliferativos/inmunología , Trastornos Linfoproliferativos/metabolismo , Masculino , Linaje
3.
Med Lav ; 106(5): 325-32, 2015 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-26384258

RESUMEN

The III Italian Consensus Conference on Pleural Mesothelioma (MM) convened on January 29th 2015. This report presents the conclusions of the 'Epidemiology, Public Health and Occupational Medicine' section. MM incidence in 2011 in Italy was 3.64 per 100,000 person/years in men and 1.32 in women. Incidence trends are starting to level off. Ten percent of cases are due to non-occupational exposure. Incidence among women is very high in Italy, because of both non-occupational and occupational exposure. The removal of asbestos in place is proceeding slowly, with remaining exposure. Recent literature confirms the causal role of chrysotile. Fibrous fluoro-edenite was classified as carcinogenic by IARC (Group 1) on the basis of MM data. A specific type (MWCNT-7) of Carbon Nanotubes was classified 2B. For pleural MM, after about 45 years since first exposure, the incidence trend slowed down; with more studies needed. Cumulative exposure is a proxy of the relevant exposure, but does not allow to distinguish if duration or intensity may possibly play a prominent role, neither to evaluate the temporal sequence of exposures. Studies showed that duration and intensity are independent determinants of MM. Blood related MM are less than 2.5%. The role of BAP1 germline mutations is limited to the BAP1 cancer syndrome, but negligible for sporadic cases. Correct MM diagnosis is baseline; guidelines agree on the importance of the tumor gross appearance and of the hematoxylin-eosin-based histology. Immunohistochemical markers contribute to diagnostic confirmation: the selection depends on morphology, location, and differential diagnosis. The WG suggested that 1) General Cancer Registries and ReNaM Regional Operational Centres (COR) interact and systematically compare MM cases; 2) ReNaM should report results presenting the diagnostic certainty codes and the diagnostic basis, separately; 3) General Cancer Registries and COR should interact with pathologists to assure the up-to-date methodology; 4) Necroscopy should be practiced for validation. Expert referral centres could contribute to the definition of uncertain cases. Health surveillance should aim to all asbestos effects. No diagnostic test is recommended for MM screening. Health surveillance should provide information on risks, medical perspective, and smoking cessation. The economic burden associated to MM was estimated in 250,000 Euro per case.


Asunto(s)
Neoplasias Pulmonares , Mesotelioma , Enfermedades Profesionales , Neoplasias Pleurales , Amianto/efectos adversos , Humanos , Italia , Neoplasias Pulmonares/epidemiología , Neoplasias Pulmonares/etiología , Mesotelioma/epidemiología , Mesotelioma/etiología , Mesotelioma Maligno , Enfermedades Profesionales/epidemiología , Enfermedades Profesionales/etiología , Medicina del Trabajo , Neoplasias Pleurales/epidemiología , Neoplasias Pleurales/etiología , Salud Pública
4.
Nat Genet ; 21(2): 169-75, 1999 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-9988267

RESUMEN

Diamond-Blackfan anaemia (DBA) is a constitutional erythroblastopenia characterized by absent or decreased erythroid precursors. The disease, previously mapped to human chromosome 19q13, is frequently associated with a variety of malformations. To identify the gene involved in DBA, we cloned the chromosome 19q13 breakpoint in a patient with a reciprocal X;19 chromosome translocation. The breakpoint occurred in the gene encoding ribosomal protein S19. Furthermore, we identified mutations in RPS19 in 10 of 40 unrelated DBA patients, including nonsense, frameshift, splice site and missense mutations, as well as two intragenic deletions. These mutations are associated with clinical features that suggest a function for RPS19 in erythropoiesis and embryogenesis.


Asunto(s)
Anemia de Fanconi/genética , Mutación , Proteínas Ribosómicas/genética , Secuencia de Aminoácidos , Cromosomas Humanos Par 19/genética , Cósmidos , Femenino , Humanos , Masculino , Datos de Secuencia Molecular , Linaje , Proteínas Ribosómicas/biosíntesis , Proteínas Ribosómicas/química , Análisis de Secuencia de ADN , Translocación Genética , Cromosoma X/genética
5.
Nat Genet ; 16(4): 368-71, 1997 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-9241274

RESUMEN

Diamond-Blackfan anaemia (DBA; MIM#205900) is a rare disorder manifested as a pure red-cell aplasia in the neonatal period or in infancy. The clinical hallmark of DBA is a selective decrease in erythroid precursors and anaemia. Other lineages are usually normal and the peripheral white blood cell count is normal. In approximately one-third of cases, the disease is associated with a wide variety of congenital anomalies and malformations. Most cases are sporadic, but 10-20% of them follow a recessive or a dominant inheritance pattern. A female with DBA and a chromosomal translocation involving chromosome 19q was recently identified. We undertook a linkage analysis with chromosome 19 markers in multiplex DBA families of Swedish, French, Dutch, Arabic and Italian origin. Significant linkage to chromosome 19q13 was established for dominant and recessive inherited DBA with a peak lod score at D19S197 (Zmax = 7.08, theta = 0.00). Within this region, a submicroscopic de novo deletion of 3.3 Mb was identified in a patient with DBA. The deletion coincides with the translocation break-point and, together with key recombinations, restricts the DBA gene to a 1.8-Mb region. The results suggest that, despite its clinical heterogeneity, DBA is genetically homogeneous for a gene in 19q13.


Asunto(s)
Mapeo Cromosómico , Cromosomas Humanos Par 19 , Anemia de Fanconi/genética , Adulto , Canales de Calcio/genética , Proteínas de Unión al Calcio/genética , Antígeno Carcinoembrionario/genética , Proteínas de Unión al ADN/genética , Femenino , Humanos , Hibridación Fluorescente in Situ , Lactante , Masculino , Repeticiones de Microsatélite , Proteínas Musculares/genética , Linaje , Canal Liberador de Calcio Receptor de Rianodina , Factor de Crecimiento Transformador beta/genética , Proteína 1 de Reparación por Escisión del Grupo de Complementación Cruzada de las Lesiones por Rayos X
6.
Mutat Res ; 708(1-2): 11-20, 2011 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-21277872

RESUMEN

Malignant pleural mesothelioma (MPM) is a rare aggressive tumor associated with asbestos exposure. The possible role of genetic factors has also been suggested and MPM has been associated with single nucleotide polymorphisms (SNPs) of xenobiotic and oxidative metabolism enzymes. We have identified an association of the DNA repair gene XRCC1 with MPM in the population of Casale Monferrato, a town exposed to high asbestos pollution. To extend this observation we examined 35 SNPs in 15 genes that could be involved in MPM carcinogenicity in 220 MPM patients and 296 controls from two case-control studies conducted in Casale (151 patients, 252 controls) and Turin (69 patients, 44 controls), respectively. Unconditional multivariate logistic regression was used to estimate odds ratios (ORs) and 95% confidence intervals (95% CIs). Two DNA repair genes were associated with MPM, i.e. XRCC1 and ERCC1. Considering asbestos-exposed only, the risk increased with the increasing number of XRCC1-399Q alleles (Casale: OR=1.44, 95%CI 1.02-2.03; Casale+Turin: OR=1.34, 95%CI 0.98-1.84) or XRCC1 -77T alleles (Casale+Turin: OR=1.33, 95%CI 0.97-1.81). The XRCC1-TGGGGGAACAGA haplotype was significantly associated with MPM (Casale: OR=1.76, 95%CI 1.04-2.96). Patients heterozygotes for ERCC1 N118N showed an increased OR in all subjects (OR=1.66, 95%CI 1.06-2.60) and in asbestos-exposed only (OR=1.59, 95%CI 1.01-2.50). When the dominant model was considered (i.e. ERCC1 heterozygotes CT plus homozygotes CC versus homozygotes TT) the risk was statistically significant both in all subjects (OR=1.61, 95%CI 1.06-2.47) and in asbestos-exposed only (OR=1.56, 95%CI 1.02-2.40). The combination of ERCC1 N118N and XRCC1 R399Q was statistically significant (Casale: OR=2.02, 95%CI 1.01-4.05; Casale+Turin: OR=2.39, 95%CI 1.29-4.43). The association of MPM with DNA repair genes support the hypothesis that an increased susceptibility to DNA damage may favour asbestos carcinogenicity.


Asunto(s)
Proteínas de Unión al ADN/genética , Endonucleasas/genética , Mesotelioma/genética , Polimorfismo de Nucleótido Simple , Amianto/toxicidad , Secuencia de Bases , Estudios de Casos y Controles , Femenino , Predisposición Genética a la Enfermedad , Humanos , Masculino , Persona de Mediana Edad , Factores de Riesgo , Proteína 1 de Reparación por Escisión del Grupo de Complementación Cruzada de las Lesiones por Rayos X
7.
J Clin Pathol ; 59(4): 440-2, 2006 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-16567474

RESUMEN

BACKGROUND: Familial tumoral calcinosis (FTC) is a rare autosomal recessive disease characterised by the development of multiple calcified masses in periarticular soft tissues; GALNT3 gene mutations have recently been described in an African American and in a Druse Arab family with FTC. OBJECTIVE: To report the clinical and histological features caused by a new GALNT3 mutation in a white family. RESULTS: Homozygosity for the nonsense mutation Lys463X was found in both affected siblings, who displayed a classic phenotype, the male also having testicular microlithiasis. He is the first subject described with testicular microlithiasis in FTC. CONCLUSIONS: The high testicular expression of GALNT3 suggests that the gene alteration could act locally by causing deposition of calcium, and the testis may be an underestimated site of calcification in FTC. Autoimmune diseases are present in several members of the family. Although immune disorders have been described in FTC, autoimmunity does not segregate with the GALNT3 mutation in this family.


Asunto(s)
Calcinosis/genética , Codón sin Sentido , Litiasis/genética , N-Acetilgalactosaminiltransferasas/genética , Proteínas de Neoplasias/genética , Enfermedades Testiculares/genética , Enfermedades Autoinmunes/genética , Enfermedades Autoinmunes/metabolismo , Calcinosis/metabolismo , Calcinosis/patología , Niño , Humanos , Italia , Litiasis/metabolismo , Litiasis/patología , Masculino , Linaje , Enfermedades Testiculares/etnología , Enfermedades Testiculares/metabolismo , Población Blanca , Polipéptido N-Acetilgalactosaminiltransferasa
8.
Mutat Res ; 599(1-2): 124-34, 2006 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-16564556

RESUMEN

Differences in response to carcinogenic agents are due to the allelic variants of the genes that control it. Key genes are those involved in the repair of the DNA damage caused by such agents. This paper describes the results of a case-control epidemiological study designed to determine the genotypes of four of these genes in persons exposed to a single genotoxic factor, i.e. asbestos, who had or had not developed malignant mesothelioma (MM). Our working hypothesis was that an imperfect DNA repair, as revealed by subtle polymorphic variants, could reduce protection against the chronic DNA insult provoked by asbestos and eventually result in mutagenesis and cancer. Seven variants (i.e. XRCC1-R399Q-NCBI SNP, XRCC1-R194W, XRCC3-T241M, XRCC3-IVS6-14, XPD-K751Q, XPD-D312N, OGG1-S326C) were investigated in 81 patients and 110 age and sex-matched controls, all residents at Casale Monferrato, a Piedmontese town highly exposed to asbestos pollution. Unconditional multivariable logistic regression was used to estimate odds ratios (ORs) and 95% confidence intervals (CIs). When considered as a categorical variable, XRCC1-399Q showed an increased OR both in heterozygotes (OR=2.08; 95% CI=1.00-4.33) and homozygotes (2.38; 95% CI=0.82-6.94), although individual ORs were not significant. When it was considered as a continuous variable OR was significant (OR=1.68; 95% CI: 1.02-2.75). When genotypes were divided into "non-risk" and "risk" genotypes, i.e. those thought to be associated with increased risk in the light of the functional significance of the variants, XRCC1-399Q (Q homozygotes+Q/R heterozygotes versus R homozygotes) had an OR=2.147 (95% CI: 1.08-4.28), whereas that of XRCC3-241T (T homozygotes+M/T heterozygotes versus M homozygotes) was 4.09 (95% CI: 1.26-13.21) and that of OGG1-326C was increased, though not significantly. None of the haplotypes showed a significantly different frequency between patients and controls. This is the first report of an association between polymorphisms in DNA repair genes and asbestos-associated MM. Our data indicate that genetic factors are involved in MM development.


Asunto(s)
Amianto/efectos adversos , Reparación del ADN/genética , Mesotelioma/etiología , Mesotelioma/genética , Neoplasias Pleurales/etiología , Neoplasias Pleurales/genética , Polimorfismo Genético , Anciano , Secuencia de Bases , Estudios de Casos y Controles , ADN Glicosilasas/genética , Cartilla de ADN/genética , ADN de Neoplasias/genética , Proteínas de Unión al ADN/genética , Femenino , Frecuencia de los Genes , Haplotipos , Humanos , Italia , Masculino , Persona de Mediana Edad , Factores de Riesgo , Proteína 1 de Reparación por Escisión del Grupo de Complementación Cruzada de las Lesiones por Rayos X , Proteína de la Xerodermia Pigmentosa del Grupo D/genética
9.
Cancer Lett ; 378(2): 120-30, 2016 08 10.
Artículo en Inglés | MEDLINE | ID: mdl-27181379

RESUMEN

BAP1 germline mutations predispose to a cancer predisposition syndrome that includes mesothelioma, cutaneous melanoma, uveal melanoma and other cancers. This co-occurrence suggests that these tumors share a common carcinogenic pathway. To evaluate this hypothesis, we studied 40 Italian families with mesothelioma and/or melanoma. The probands were sequenced for BAP1 and for the most common melanoma predisposition genes (i.e. CDKN2A, CDK4, TERT, MITF and POT1) to investigate if these genes may also confer susceptibility to mesothelioma. In two out of six families with both mesothelioma and melanoma we identified either a germline nonsense mutation (c.1153C > T, p.Arg385*) in BAP1 or a recurrent pathogenic germline mutation (c.301G > T, p.Gly101Trp) in CDKN2A. Our study suggests that CDKN2A, in addition to BAP1, could be involved in the melanoma and mesothelioma susceptibility, leading to the rare familial cancer syndromes. It also suggests that these tumors share key steps that drive carcinogenesis and that other genes may be involved in inherited predisposition to malignant mesothelioma and melanoma.


Asunto(s)
Biomarcadores de Tumor/genética , Codón sin Sentido , Inhibidor p18 de las Quinasas Dependientes de la Ciclina/genética , Mutación de Línea Germinal , Melanoma/genética , Mesotelioma/genética , Neoplasias Cutáneas/genética , Proteínas Supresoras de Tumor/genética , Ubiquitina Tiolesterasa/genética , Adolescente , Adulto , Anciano , Biomarcadores de Tumor/análisis , Inhibidor p16 de la Quinasa Dependiente de Ciclina , Inhibidor p18 de las Quinasas Dependientes de la Ciclina/análisis , Análisis Mutacional de ADN , Bases de Datos Factuales , Femenino , Estudios de Asociación Genética , Predisposición Genética a la Enfermedad , Herencia , Humanos , Inmunohistoquímica , Italia , Masculino , Melanoma/química , Melanoma/patología , Mesotelioma/química , Mesotelioma/patología , Persona de Mediana Edad , Linaje , Fenotipo , Factores de Riesgo , Neoplasias Cutáneas/química , Neoplasias Cutáneas/patología , Proteínas Supresoras de Tumor/análisis , Ubiquitina Tiolesterasa/análisis , Adulto Joven
10.
Exp Hematol ; 25(12): 1270-7, 1997 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-9357971

RESUMEN

Diamond-Blackfan anemia (DBA) is a congenital pure red blood cell aplasia that often requires lifelong transfusional therapy. Autosomal dominant and recessive inheritance have both been reported, suggesting genetic heterogeneity, but most cases occur sporadically. The origin of impaired erythropoiesis is unknown. Several erythroid growth factors have been thought to have a role in the pathogenesis of DBA. However, there is neither molecular nor clinical evidence for the involvement of erythropoietin (EPO), its receptor, stem cell factor (SCF), or interleukin (IL)-3, even if the addition of SCF to IL-3 and EPO does significantly increase the growth of erythroid progenitors in in vitro cultures in most patients. In this work we evaluated the possible role of another early-acting erythroid growth factor, IL-9. We found that the addition of IL-9 to SCF, IL-3, and EPO further increases burst-forming unit-erythroid growth in in vitro cultures of those DBA patients who responded to SCF. To investigate the role of the IL-9 gene, we evaluated its segregation in 22 families with members who have DBA by using a polymorphic microsatellite located within its intron 4. Lod score analysis ruled out any statistically significant involvement of the IL-9 gene in the pathogenesis of DBA. Moreover, linkage analysis with 11 highly polymorphic markers spanning 5q31.1-q33.2 excluded this region, which is included in the major cluster of genes active in hematopoiesis of the human genome.


Asunto(s)
Anemia de Fanconi/patología , Hematopoyesis , Interleucina-9/fisiología , Adolescente , Niño , Mapeo Cromosómico , Cromosomas Humanos Par 5 , Eritropoyetina/administración & dosificación , Anemia de Fanconi/tratamiento farmacológico , Anemia de Fanconi/genética , Femenino , Ligamiento Genético , Hematopoyesis/efectos de los fármacos , Factores de Crecimiento de Célula Hematopoyética/farmacología , Humanos , Lactante , Interleucina-3/administración & dosificación , Interleucina-9/genética , Masculino , Repeticiones de Microsatélite , Factor de Células Madre/administración & dosificación
11.
Eur J Hum Genet ; 3(5): 294-302, 1995.
Artículo en Inglés | MEDLINE | ID: mdl-8556304

RESUMEN

In order to identify the molecular basis of phenylketonuria (PKU) in Italy, we screened the entire coding sequence of the phenylalanine hydroxylase gene in 20 Italian PKU patients, whose origins are scattered throughout Italy. The frequency of each identified mutation and of 5 other European mutations was determined within a panel of 92 Italian PKU patients. This approach allowed us to identify 20 different PKU mutations and characterize 64% of the Italian PKU chromosomes. Eleven mutations (IVS10nt546, L48S, R158Q, R261Q, P281L, R261X, R252W, delta T55, IVS7nt1, IVS12nt1, Y414C) represent 55.4% of the Italian PKU alleles, the most common mutations being IVS10nt546 (12.4%) and L48S (9%). All the other mutations are very rare. These data confirm the great heterogeneity expected from previous RFLP haplotype studies. Genotype/phenotype correlation allowed for assessment of the clinical impact of the 20 identified mutations.


Asunto(s)
Fenilcetonurias/genética , Alelos , Secuencia de Bases , Análisis Mutacional de ADN , Cartilla de ADN , Heterogeneidad Genética , Genotipo , Humanos , Italia/epidemiología , Epidemiología Molecular , Datos de Secuencia Molecular , Mutación , Sondas de Oligonucleótidos , Fenotipo , Fenilalanina Hidroxilasa/genética , Fenilcetonurias/etnología , Polimorfismo de Longitud del Fragmento de Restricción
12.
FEBS Lett ; 308(3): 267-70, 1992 Aug 24.
Artículo en Inglés | MEDLINE | ID: mdl-1505665

RESUMEN

Overexpression of transforming growth factor beta 1 (TGF beta 1) and increased transcription of pro-collagen type I, are known to represent major events implicated in the development of liver fibrosis under either experimental or clinical conditions. Here we report that long-term dietary vitamin E supplementation in animals undergoing an experimental model of liver fibrosis (induced by chronic treatment of rats with carbon tetrachloride) results in a net inhibition of both hepatic TGF beta 1 and alpha 2 (I) procollagen mRNA levels. Moreover, of striking interest is the observation that vitamin E supplementation per so down-modulates basal levels of TGF beta 1 mRNA in the liver of untreated animals, suggesting that a dietary regimen rich in vitamin E may potentially interfere with both the initiation and progression of the fibrosclerotic processes.


Asunto(s)
Hígado/efectos de los fármacos , Vitamina E/farmacología , Animales , Dieta , Expresión Génica/efectos de los fármacos , Hígado/metabolismo , Cirrosis Hepática Experimental/metabolismo , Cirrosis Hepática Experimental/prevención & control , Masculino , Procolágeno/biosíntesis , ARN Mensajero/genética , Ratas , Ratas Endogámicas , Transcripción Genética , Factor de Crecimiento Transformador beta/genética , Vitamina E/administración & dosificación
13.
Hematol J ; 2(4): 220-7, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11920253

RESUMEN

INTRODUCTION: In acquired immune deficiency syndrome patients, apoptosis of uninfected lymphocytes may contribute to development of immune deficiency. This process may involve recruitment of Fas by human immunodeficiency virus products. In line with this possibility, the viral envelope glycoprotein gp120 does not induce death of T cells from subjects with the autoimmune/lymphoproliferative syndrome displaying defective Fas function. This study evaluates the possibility that Fas function defects delay progression of HIV-induced immune deficiency. MATERIALS AND METHODS: The susceptibility to Fas-induced cell death was assessed on T cells from 18 'long-term non-progressor', four 'non-progressor', four 'progressor' asymptomatic HIV-1-infected, and nine AIDS patients using anti-Fas monoclonal antibodies. RESULTS: Fas-induced cell death was significantly lower in long-term non-progressors and non-progressors than in normal controls, progressors, and AIDS. The single-patient data showed that 9/18 long-term non-progressors and 3/4 non-progressors, but no progressors or AIDS were resistant to Fas. Analysis of the uninfected parents of two long-term non-progressors displaying decreased Fas-function showed that the mother of one of them and the father of the other displayed the same Fas function defect as their children. Fusion of T cells from Fas-resistant individuals with a Fas-sensitive cell line gave rise to Fas-resistant hybrid lines not carrying HIV, which suggests that the resistant phenotype is due to molecules exerting a dominant negative effect on a normal Fas system. CONCLUSION: These data suggest that Fas-resistance in long-term non-progressors may be due to inherited alterations of the Fas signaling pathway and may be a novel factor in delayed progression.


Asunto(s)
Síndrome de Inmunodeficiencia Adquirida/diagnóstico , Sobrevivientes de VIH a Largo Plazo , Receptor fas/fisiología , Síndrome de Inmunodeficiencia Adquirida/genética , Anticuerpos Monoclonales , Apoptosis/genética , Apoptosis/fisiología , Estudios de Casos y Controles , Progresión de la Enfermedad , Salud de la Familia , Humanos , Pronóstico , Transducción de Señal/genética , Transducción de Señal/fisiología , Linfocitos T/metabolismo , Linfocitos T/fisiología , Linfocitos T/virología , Receptor fas/genética , Receptor fas/inmunología
14.
DNA Cell Biol ; 12(10): 945-9, 1993 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-8274226

RESUMEN

Osmium tetroxide and hydroxylamine are used to detect mutations in DNA and RNA after hybridization of mutant and wild-type DNA. Mismatched T and C bases, respectively, are modified by these reagents and the DNA strand cleaved at the mismatched bases by subsequent treatment with piperidine. This allows detection and location of the mutation. Although most T.G mismatches have been reported to be reactive to osmium tetroxide, some have been reported to be unreactive. The aim of this study was to collect and analyze the reactive and unreactive T.G mismatches. We have collected sequence contexts of all reactive and unreactive T.G mismatches for analysis. This involves 10 unreactive T.G mismatches (plus one T.C) and 19 reactive T.G mismatches. Sequence effects of bases surrounding these mismatches must influence this reactivity. There must be many types of such sequence effects. We postulate that because of the dominance of 5' G bases near the T of unreactive T.G mismatches and the absence of 5' G bases in reactive T.G mismatches that the stacking of the 5' G on the mismatched T is the reason for this lack of reactivity in the majority of the cases studied here.


Asunto(s)
Guanina , Tetróxido de Osmio/química , Timina , Secuencia de Bases , Hidroxilamina , Hidroxilaminas/química , Ácidos Nucleicos Heterodúplex , Oligodesoxirribonucleótidos
15.
Paediatr Drugs ; 2(5): 345-55, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-11022796

RESUMEN

Diamond Blackfan Anaemia (DBA) is a congenital disease characterised by defective erythroid progenitor maturation. It is usually diagnosed during the first year of life. The main clinical sign is profound isolated normochromic or macrocytic anaemia, with normal numbers and function of the other haemopoietic cells. Reticulocyte counts in patients with DBA are very low. Bone marrow reflects the defective erythropoiesis, showing a very low number of erythropoietic precursors and a reduction of erythroid burst-forming unit progenitor cells. The proliferation and differentiation of the other lineages are normal. More than one-third of patients have malformations, most often involving the upper limbs and head, and the urogenital or cardiovascular systems. However, the link between these malformations and defective erythropoiesis is unclear and a defect in a molecule acting on both early embryonic development and haematopoiesis has been proposed. Whereas most cases are sporadic, inheritance is observed in 10% of patients, with a dominant or, more rarely, recessive pattern. One locus on chromosome 19q13.2 encoding ribosomal protein S19 accounts for a quarter of patients with either the dominant or the sporadic form. Families not linked with this locus have also been described. The diagnosis of DBA may be difficult and differential diagnoses include Fanconi's anaemia and acquired erythroid aplasias. Erythrocyte adenosine deaminase levels are generally high in DBA patients, which may help in the diagnosis, but they are not pathognomic. Corticosteroids are the main treatment option in DBA and these agents induce erythropoiesis in over 60% of patients. Some patients achieve complete remission, which may be either corticosteroid-induced or spontaneous. The increased in vitro erythropoiesis occasionally induced by the addition of specific cytokines, namely interleukin (IL)-3 and stem cell factor (SCF), has suggested their use in vivo. However, few patients have responded to IL-3, whereas SCF administration, though interesting in theory, has not yet been attempted. Patients who do not respond to corticosteroids and those who have to discontinue treatment because of adverse events must rely on long term transfusions, and are thus exposed to all of the associated complications. Bone marrow or cord blood transplantation has been performed in some patients. The former approach is burdened with severe complications and high mortality.


Asunto(s)
Anemia de Fanconi/diagnóstico , Anemia de Fanconi/terapia , Corticoesteroides/uso terapéutico , Transfusión Sanguínea , Trasplante de Médula Ósea , Anemia de Fanconi/etiología , Factor Estimulante de Colonias de Granulocitos y Macrófagos/uso terapéutico , Humanos , Lactante , Interleucina-3/uso terapéutico
16.
Clin Nephrol ; 56(6): 467-74, 2001 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11770798

RESUMEN

BACKGROUND: Cystinuria is an inherited disorder of cystine and dibasic amino acids transport that results in urolithiasis because of poor cystine solubility. Three cystinuria phenotypes, differentiated according to urinary amino acid excretion in obligate heterozygotes, were regarded as allelic variants of a monogenic disease. Two mutated amino acid transporter genes, however, have been recently identified as responsible for cystinuria. Mutations in the SLC3A1 gene. encoding for the heavy subunit of the transporter protein rBAT, were associated with type I cystinuria, whereas type II and III cystinuria were associated with mutations in the SLC7A9 gene, encoding for a light subunit of rBAT. Lysine and arginine metabolism have, therefore, been evaluated in cystinuria homozygotes and heterozygotes to better define the cystinuria phenotypes and their correlations with these emerging genotypes. PATIENTS AND METHODS: Lysine and arginine intestinal absorption and renal excretion were assessed by oral loading and compared to normal controls. Seven cystinuria homozygotes and 7 obligate heterozygotes belonging to the different types received alternately an oral dose of 0.5 mmol/kg body weight lysine or arginine. Plasma concentrations of lysine, arginine, ornithine (derived from rapid arginine conversion) were measured 0, 1, 2, and 3 hours after loading. Their urinary concentrations were measured in morning urine and in urine collected 0-6 hours after loading. RESULTS: Gut lysine absorption was deficient in type II and III, and normal in type I cystinuria homozygotes. Impaired arginine intestinal absorption, as well as massive lysine, arginine, and ornithine hyperexcretion were shared by all homozygotes, irrespective of the type. All heterozygotes shared normal lysine absorption, whereas arginine absorption was slightly impaired in type II and III heterozygotes, which also displayed high lysine, arginine, and ornithine urinary excretion after loading. CONCLUSIONS: Two cystinuria phenotypes, type I and non-type I, can be identified in both homozygous and heterozygous cystinuric subjects by oral loading tests with lysine and arginine. In agreement with recent molecular findings, non-type I cystinuria comprises mentioned type II and type III, which constitute allelic variants of a cystine and dibasic amino acid transport disorder distinct from type I cystinuria.


Asunto(s)
Sistemas de Transporte de Aminoácidos Básicos , Arginina/metabolismo , Cistinuria/genética , Cistinuria/metabolismo , Lisina/metabolismo , Fenotipo , Adolescente , Adulto , Alelos , Arginina/orina , Proteínas Portadoras/genética , Cistinuria/complicaciones , Femenino , Heterocigoto , Homocigoto , Humanos , Absorción Intestinal/fisiología , Lisina/orina , Masculino , Glicoproteínas de Membrana/genética , Persona de Mediana Edad , Ornitina/metabolismo , Ornitina/orina , Cálculos Urinarios/etiología
17.
Arch Mal Coeur Vaiss ; 83(8): 1249-51, 1990 Jul.
Artículo en Francés | MEDLINE | ID: mdl-2124463

RESUMEN

Aim of this study is to evaluate whether among type I diabetic adolescents (IDDM) the erythrocyte Na-Li countertransport (CNT Na-Li) is correlated with arterial pressure and tubular sodium reabsorption. We have studied 16 IDDM adolescents (age 15 +/- 0.5 year) et 15 normal subjects (age 14.5 +/- 1 year). CNT Na-Li, creatinine and lithium clearances (as markers of glomerular filtration rate and proximal tubular sodium reabsorption) have been measured in all subjects and nocturnal urinary albumin excretion rate (UAER) was measured in IDDM adolescents. CNT Na-Li was 308 +/- 26 mumol Li/l RBC/h in IDDM adolescents and 211 +/- 74 mumol Li/l RBC/h in controls (p less than 0.01). The fractional excretion of lithium (FELi) was significantly reduced in IDDM adolescents compared to normal subjects (12 +/- 2 vs 19 +/- 2%; p less than 0.01). Among the IDDM adolescents, 5 had the CNT Na-Li higher than the 95th percentile of controls (greater than 360 mumol Li/l GR/h); their systolic arterial pressure was significantly higher than in diabetics with normal CNT Na-Li (126 +/- 2 vs 116 +/- 2; p = 0.03), while there were no differences for diabetes duration, glycemic control, serum potassium, creatinine clearance, FELi and UAER. The relationship between CNT Na-Li and arterial pressure in IDDM adolescents deserves further studies.


Asunto(s)
Antiportadores , Presión Sanguínea , Proteínas Portadoras/metabolismo , Diabetes Mellitus Tipo 1/sangre , Eritrocitos/metabolismo , Adolescente , Proteínas Portadoras/sangre , Diabetes Mellitus Tipo 1/fisiopatología , Femenino , Humanos , Hipertensión/fisiopatología , Masculino
18.
Pediatr Med Chir ; 6(4): 579-81, 1984.
Artículo en Italiano | MEDLINE | ID: mdl-6335914

RESUMEN

The association of insulin-dependent diabetes mellitus (IDDM) and progressive optic atrophy, occasionally associated with other disorders, is known as Wolfram syndrome. Here is reported the case history of a 14 years old girl who presented IDDM, progressive optic atrophy, hearing loss, disturbed colour vision, hemeralopia and retarded sexual maturation.


Asunto(s)
Diabetes Mellitus Tipo 1/complicaciones , Trastornos del Crecimiento/complicaciones , Trastornos de la Visión/complicaciones , Adolescente , Defectos de la Visión Cromática/complicaciones , Femenino , Humanos , Maduración Sexual , Síndrome
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA