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1.
Nutrients ; 11(4)2019 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-31010126

RESUMO

Multiple common variants in transmembrane protease serine 6 (TMPRSS6) were associated with the plasma iron concentration in genome-wide association studies, but their effect in young children where anemia and iron deficiency (ID) were prevalent has not been reported, particularly taking account of iron intake. This study aims to investigate whether TMPRSS6 SNPs (rs855791 and rs4820268) and iron intake are associated with a low iron and hemoglobin concentration in under-two-year-old children. The study analyzed the baseline of a randomized trial (NUPICO, ClinicalTrials.gov NCT01504633) in East Lombok, Indonesia. Children aged 6-17 months (n = 121) were included in this study. The multiple linear regressions showed that TMPRSS6 decreased serum ferritin (SF) by 4.50 g/L per copy minor allele (A) of rs855791 (p = 0.08) and by 5.00 µg/L per copy minor allele (G) of rs4820268 (p = 0.044). There were no associations between rs855791 and rs4820268 with soluble transferrin receptor (sTfR) and hemoglobin (Hb) concentration (rs855791; p = 0.38 and p = 0.13, rs4820268; p = 0.17 and p = 0.33). The finding suggests the need for further studies to explore whether the nutrient recommendation for iron should be based on genetic characteristics, particularly for children who have mutation in TMPRSS6.


Assuntos
Anemia Ferropriva/genética , Povo Asiático/genética , Dieta , Genótipo , Ferro/sangue , Proteínas de Membrana/genética , Polimorfismo de Nucleotídeo Único , Serina Endopeptidases/genética , Alelos , Anemia Ferropriva/sangue , Feminino , Ferritinas/sangue , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Hemoglobinas/metabolismo , Humanos , Indonésia , Lactente , Ferro/administração & dosagem , Deficiências de Ferro , Modelos Lineares , Masculino , Mutação , Necessidades Nutricionais , Estado Nutricional , Receptores da Transferrina/sangue , Transferrina/metabolismo
2.
Hemoglobin ; 42(1): 1-6, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29513125

RESUMO

We report a new hemoglobin (Hb) variant, Hb Hachioji (HBB: c.187C>T), which was detected in a 32-year-old male with hemolytic anemia. The proband had undergone splenectomy in his childhood after being diagnosed with hereditary spherocytosis (HS) with no clinical improvement. A recent study showed that Heinz bodies were frequently observed in his red cells, however, no abnormal band was separated by isoelectric focusing (IEF), and the isopropanol (instability) test was negative. Direct sequencing revealed that the proband was a heterozygous carrier of a novel mutation (GCT>GTT) at codon 62 of the ß-globin gene, leading to an alanine to valine substitution. This variant was named Hb Hachioji. Characterization at the mRNA level by cDNA sequencing detected ßHachioji mRNA, as well as ßA mRNA. Subsequently, study of the proband's family indicated that his father was a carrier of this Hb variant, although unexpectedly, the father was asymptomatic and clinically healthy. Oxygen affinity measurement of total Hb showed no alteration in the P50 and oxygen equilibrium curve. The presence of Hb Hachioji was confirmed by mass spectrometry (MS). Hb Hachioji comprised approximately 50.0% of the total Hb and was a stable variant. The phenotypic discrepancy between these two carriers suggests that Hb Hachioji may not be associated with the hemolytic involvement in the proband. P4.2Nippon, which is the primary cause of most cases of Japanese HS, was absent in the proband's parents. The coexistence of glucose-6-phosphate dehydrogenase (G6PD) deficiency was ruled out. Thus, the cause of hemolytic involvement in this patient remains unclear.


Assuntos
Anemia Hemolítica/genética , Adulto , Doença Crônica , Hemoglobinas Anormais/genética , Heterozigoto , Humanos , Masculino , Mutação de Sentido Incorreto , Fenótipo , Polimorfismo de Nucleotídeo Único , Globinas beta/genética
3.
Asia Pac J Clin Nutr ; 24(2): 323-8, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26078250

RESUMO

BACKGROUND/AIMS: Long-chain polyunsaturated fatty acids (LC-PUFA) are regarded as essential for child cognition. Genetic variation in fatty acid (FA) desaturase enzyme (FADS) has been recognized as an important effect modifier in the relation between LC-PUFA and child cognitive function. This study aimed to identify the distribution of genetic variant (genotype) SNP rs174468 and to assess plasma FA and developmental outcome by the genotype among under-2 year old Sasaknese Indonesian children. METHODS: Data was collected at baseline of a randomized trial (NUPICO, clinicaltrials.gov NCT01504633) in East Lombok district, Indonesia. Breastfed, 12- 17 month old children were recruited and 240 subjects were included in the study. Child cognition was assessed as Bayley Mental Developmental Index (MDI). RESULTS: From 206 subjects whose blood samples can be collected, only two genotypes were found (90.3% GG homozygotes, 9.7% AG heterozygotes), and minor allele AG was significantly associated with higher level of arachidonic acid (20:4 n-6), n-6 LC-PUFA and FADS1 index. MDI score was associated with a FADS2 index (DHA:EPA ratio) but not genotype (Adjusted R-square= 0.043). CONCLUSIONS: FADS2 index was associated with cognitive function. No difference was found between children with GG and AG genotypes who were all breastfed and not low birth weight.


Assuntos
Cognição/fisiologia , Ácidos Graxos Dessaturases/genética , Ácidos Graxos Dessaturases/fisiologia , Ácidos Graxos Insaturados/sangue , Variação Genética/genética , Alelos , Ácido Araquidônico/sangue , Dessaturase de Ácido Graxo Delta-5 , Ácidos Graxos Ômega-6/sangue , Feminino , Genótipo , Humanos , Indonésia , Lactente , Masculino , Família Multigênica/genética
4.
Hemoglobin ; 39(2): 121-6, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25690802

RESUMO

Here we describe a Japanese patient with mild ß-thalassemia (ß-thal) with an intact ß-globin gene but a new missense mutation of c.947G > A or p.C316Y in the erythroid Krüppel-Like Factor (KLF1) gene which is strongly associated with the expression of the ß-globin gene. The association of the KLF1 mutation with ß-thal, is here described. The p.C316Y mutation occurred at one of the cysteines that constitute the second zinc finger motif of KLF1, and would have changed the zinc finger conformation to impair the DNA binding properties or the promoter function of the ß-globin gene. Our expression study found that the mutant KLF1 gene had a markedly negative effect on the ß-globin gene expression, or 7.0% of that of its normal counterpart. A presumed heterozygous state, or equimolar presence of the mutant and normal KLF1s reduced the expression rate to 70.0% of the normal alone. This degree of the decrease may explain the very mild phenotype of the patient's ß-thal. Furthermore, the patient's whole-exome analysis using next-generation sequencing revealed that the ß-thal defect is caused by only this KLF1 gene mutation. The Hb A2 and Hb F levels that are frequently elevated in KLF1 mutations were elevated by 4.1 and 1.3%, respectively, in this case. The contribution to their elevation by KLF1: p.C316Y is uncertain.


Assuntos
Fatores de Transcrição Kruppel-Like/genética , Mutação , Talassemia beta/diagnóstico , Talassemia beta/genética , Adulto , Sequência de Aminoácidos , Povo Asiático/genética , Códon , DNA Complementar/química , DNA Complementar/genética , Exoma , Expressão Gênica , Ordem dos Genes , Genes Reporter , Loci Gênicos , Heterozigoto , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Japão , Fatores de Transcrição Kruppel-Like/química , Masculino , Mutação de Sentido Incorreto , Fenótipo , Regiões Promotoras Genéticas , Dedos de Zinco/genética
5.
Hemoglobin ; 38(3): 169-72, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24611654

RESUMO

ß-Thalassemia (ß-thal), especially ß-thalassemia major (ß-TM), is reported to be related to reactive oxygen species (ROS) and enhanced oxidation status. It is reflected by increased malondialdehyde (MDA), by membrane lipid peroxidation and decreased by the newly developed total antioxidant capacity (TAC). However, there is less evidence for ß-thal minor and Hb H (ß4) disease on its association with oxidation status. On the other hand, hemolysis by glycerol lysis time (GLT50) is invariably prolonged in thalassemia. The reason for the prolongation of GLT50 is not well understood. The aim of this study was to investigate the oxidation state in ß-thal minor and Hb H disease and to find out the association of the oxidation with the prolongation of GLT50. Blood samples from 39 subjects (33 with ß-thal minor, six with Hb H disease) were collected from individuals living in Japan. The clinical screening tests and molecular identification of the thalassemias were performed. Malondialdehyde and TAC were measured using spectrophotometric analyses. In ß-thal minor and Hb H disease, the plasma MDA level was significantly elevated and the TAC reduced. A highly reversed correlation between MDA and TAC was noted. Their GLT50 levels were evidently prolonged, and the GLT50 has significant correlations with MDA and TAC. ß-Thalassemia minor and mild Hb H disease are evidently in a milieu of reduced redox state, and GLT50 prolongation in ß-thal minor and Hb H disease has a close correlation with the oxidation state, possibly by oxidative impairment of the membrane protein of the red cell.


Assuntos
Crioprotetores/farmacologia , Membrana Eritrocítica/metabolismo , Glicerol/farmacologia , Peroxidação de Lipídeos , Talassemia beta/sangue , Antioxidantes/metabolismo , Feminino , Humanos , Japão , Masculino , Malondialdeído/sangue
6.
Hemoglobin ; 37(3): 227-40, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23600595

RESUMO

A new ß-thalassemia (ß-thal) frameshift mutation was found at codon 102 (AAC>ATCAC) in a 17-year-old Japanese male and his 14-year-old sister. Both demonstrated a more severe phenotype than the usual ß-thal minor with mild hemolytic involvement. No mRNA derived from the thalassemic allele, or ß(T)mRNA, was detected in the sequencing analysis of the whole mRNA (cDNA). However, the ß(T)mRNA from the whole ßmRNA was specifically amplified by amplification refractory mutation system (ARMS), and was actually found to be present. Furthermore, quantitative polymerase chain reaction (q-PCR) demonstrated a negligible amount of ß(T)mRNA. Thus, their more severe phenotype was not caused by the "dominant type" ß-thal in which a considerable amount of the ß(T)mRNA would be expected. In fact, our proband had a total ßmRNA level that was mostly normal. Thus, the cause of a ß-thal phenotype by the frameshift mutation was ascribed to the reduced amount of mRNA. We further searched for the cause of their severe phenotype. However, factors that exacerbated the phenotype of ß-thal, such as α-globin gene triplication, coexisting iron deficiency and infection were not found. Finally, we noticed that the red cell morphology revealed ovalocytosis and small numbers of stomatocytes that were seen in the hereditary spherocytosis (HS), especially by P4.2 mutations. The sequence of the P4.2 gene disclosed heterozygous P4.2 Nippon, or missense mutation at codon 142 (GCT>ACT) on exon 3, the most common mutation of Japanese HS. Frequent mutations of other membrane proteins, Band 3 and ankyrin that are common cause of HS in the Japanese population, other than P4.2, were not detected. When HS by P4.2 Nippon develops it is homozygous, and no P4.2 protein is observed in sodium dodecilsulphate-polyacrylamide gel electrophoresis (SDS-PAGE), while in our case the amount of the P4.2 was almost normal in the SDS-PAGE. However, there are several reports that revealed more severe phenotypes of ß-thal by the coexisting abnormality of membrane protein. It is uncertain, but the presence of heterozygous P4.2 Nippon may be associated with the exacerbation of the phenotype of ß-thal minor.


Assuntos
Heterozigoto , Mutação , RNA Mensageiro/genética , Globinas beta/genética , Talassemia beta/genética , Adolescente , Sequência de Bases , Códon , Feminino , Genótipo , Humanos , Masculino , Dados de Sequência Molecular , Linhagem , Fenótipo , Análise de Sequência de DNA , Índice de Gravidade de Doença , Talassemia beta/fisiopatologia
7.
Hemoglobin ; 36(4): 399-406, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22734587

RESUMO

The 3' untranslated region (3'UTR) is known to be important to mRNA stability but the stabilization mechanism on the ß-globin gene is not fully elucidated. We speculated in our previous report that +1,506 (A>C) mutation (HGVS nomenclature: *32A>C) on the ß-globin 3'UTR causes ß-thalassemia (ß-thal) in order to destabilize the mRNA. To investigate further, we studied the expression efficiency for the mutation with a luciferase assay. We made recombinant pGL4.74 vectors in which the luciferase 3'UTR was replaced with the wild-type and mutant 3'UTR of the ß-globin gene. For a comparison experiment, recombinant vectors were made not only for this mutation but also six other mutations in the ß-globin 3'UTR which bring about ß-thal or affect mRNA stability. The +1,506 mutation led to a 30.0% lower protein expression than normal in this assay. We concluded that this mutation destabilizes mRNA and consequently decreases the ß-globin amount to finally cause ß-thal. Our study highlights the crucial area of ß-globin 3'UTR for protein expression.


Assuntos
Regiões 3' não Traduzidas/genética , Mutação , RNA Mensageiro/genética , Globinas beta/genética , Sequência de Bases , Linhagem Celular Tumoral , Regulação da Expressão Gênica , Humanos , Células K562 , Luciferases/genética , Luciferases/metabolismo , Dados de Sequência Molecular , Conformação de Ácido Nucleico , Estabilidade de RNA , RNA Mensageiro/química , RNA Mensageiro/metabolismo , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Transfecção , Globinas beta/química , Talassemia beta/genética
8.
Hemoglobin ; 36(2): 170-6, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22217218

RESUMO

ß-Thalassemia (ß-thal) is characterized by the absent or reduced production of ß-globin chains. The precise molecular lesion that causes decreased ß-globin synthesis in ß(+)-thal is difficult to predict when mutations occur in the locus control region (LCR), the promoter, the introns or 3' untranslated regions (3'UTRs). Among them, the role of the 3'UTR of ß-globin gene in mRNA stability is poorly understood, mainly due to very few cases that have mutations in this region. So far, only three mutations have been reported in the 3'UTR of ß-globin gene. Although, it is speculated that some of these reported mutations could be associated with mRNA stability, the precise molecular basis still remains unclear. We report here a novel mutation in the ß-globin gene 3'UTR [+1,506 (A>C)] in a 31-year-old Japanese male with hematological parameters suggestive of heterozygous ß-thal. Further functional studies on this novel mutation reported here, may help in understanding of the regulation and expression of the ß-globin gene and its products.


Assuntos
Regiões 3' não Traduzidas/genética , Mutação , Globinas beta/genética , Talassemia beta/genética , Adulto , Povo Asiático/genética , Sequência de Bases , Análise Mutacional de DNA , Heterozigoto , Humanos , Masculino , Dados de Sequência Molecular , Fenótipo , Estabilidade de RNA
9.
Nurs Health Sci ; 13(2): 105-13, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21595813

RESUMO

This article reports on efforts to overcome common hurdles that were faced during population-based screening for common hemoglobinopathies in the United Arab Emirates. An Internet-based approach was designed and implemented to increase the acceptance of the screening program. The process involved: an awareness campaign, a simple bilingual (Arabic/English) online consent form and registration process, the use of a barcode for sample labeling, an equipment upgrade, electronic communication of a successful registration process, test results, and a counseling process. Before the implementation of the Internet-based system, great concern was noted among the clients in terms of the availability of accurate and timely test results, the need for pretest and post-test counseling, and the way that their personal health information was handled. Lapses in information exchange between the clients who participated in the screening program for the carrier state of inherited disorders and the screening laboratory posed significant challenges. The emphasis on confidentiality and the ease of access to services was instrumental in increasing the level of acceptance of these services in our community. Based on an analysis of > 10,000 samples, we conclude that Internet-based reporting holds much promise for improving the quality of care that clients receive.


Assuntos
Hemoglobinopatias/diagnóstico , Internet , Programas de Rastreamento/métodos , Aceitação pelo Paciente de Cuidados de Saúde/estatística & dados numéricos , Coleta de Amostras Sanguíneas/métodos , Confidencialidade , Acessibilidade aos Serviços de Saúde , Humanos , Emirados Árabes Unidos
10.
Biofactors ; 19(1-2): 87-100, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-14757981

RESUMO

Erythrocyte membrane structural parameters were studied in transfusion-dependent beta-thalassemia patients, in long-term transfused patients (regularly transfused < 15 years), and in those who had not yet obtained transfusions. Controls were voluntary students up to 30 years of age without diagnosis or clinical signs of thalassemia. Membranes were isolated and investigated by sodium dodecylsulfate polyacrylamide gel electrophoresis (SDS-PAGE) and electron paramagnetic resonance (EPR) spectroscopy. Data obtained from the thiol-reactive spin label N-ethyl-maleimidoproxyl reveal immobilization of protein environment in erythrocyte membranes from thalassemic patients. SDS-PAGE shows both degradation and aggregation of membrane proteins. Thalassemic erythrocyte membranes exert higher order parameters in the hydrophobic region as determined by 16-doxyl-stearic acid. Rotational correlation times of this spin label increase only in transfused patients. Polarity is higher in membranes of all patients than in controls. In the polar interface, order parameters obtained from 5-doxyl-stearic acid increase in non-transfused and decrease in transfusion-dependent patients as compared with controls. Transfused patients exert increasing membrane order in the hydrophobic region and counter-currently decreasing order in the polar interface indicating loss of membrane integrity along with the loss of fluidity and polarity gradients and the loss the energetic barrier function of the membrane.


Assuntos
Transfusão de Sangue , Membrana Eritrocítica/química , Talassemia beta/sangue , Adolescente , Adulto , Criança , Espectroscopia de Ressonância de Spin Eletrônica , Eletroforese em Gel de Poliacrilamida , Membrana Eritrocítica/metabolismo , Feminino , Humanos , Indonésia , Masculino , Fluidez de Membrana , Valores de Referência , Marcadores de Spin , Tempo , Talassemia beta/terapia
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