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1.
Braz. j. med. biol. res ; 43(1): 107-114, Jan. 2010. tab
Artigo em Inglês | LILACS | ID: lil-535646

RESUMO

Mutations of the HFE and TFR2 genes have been associated with iron overload. HFE and TFR2 mutations were assessed in blood donors, and the relationship with iron status was evaluated. Subjects (N = 542) were recruited at the Hemocentro da Santa Casa de São Paulo, São Paulo, Brazil. Iron status was not influenced by HFE mutations in women and was independent of blood donation frequency. In contrast, men carrying the HFE 282CY genotype had lower total iron-binding capacity (TIBC) than HFE 282CC genotype carriers. Men who donated blood for the first time and were carriers of the HFE 282CY genotype had higher transferrin saturation values and lower TIBC concentrations than those with the homozygous wild genotype for the HFE C282Y mutation. Moreover, in this group of blood donors, carriers of HFE 63DD plus 63HD genotypes had higher serum ferritin values than those with the homozygous wild genotype for HFE H63D mutation. Multiple linear regression analysis showed that HFE 282CY leads to a 17.21 percent increase (P = 0.018) and a 83.65 percent decrease (P = 0.007) in transferrin saturation and TIBC, respectively. In addition, serum ferritin is influenced by age (3.91 percent, P = 0.001) and the HFE 63HD plus DD genotype (55.84 percent, P = 0.021). In conclusion, the HFE 282Y and 65C alleles were rare, while the HFE 63D allele was frequent in Brazilian blood donors. The HFE C282Y and H63D mutations were associated with alterations in iron status in blood donors in a gender-dependent manner.


Assuntos
Adulto , Feminino , Humanos , Masculino , Doadores de Sangue , Antígenos de Histocompatibilidade Classe I/genética , Ferro/sangue , Mutação , Proteínas de Membrana/genética , Receptores da Transferrina/genética , Frequência do Gene , Genótipo , Fatores Sexuais
2.
Braz J Med Biol Res ; 43(1): 107-14, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20027482

RESUMO

Mutations of the HFE and TFR2 genes have been associated with iron overload. HFE and TFR2 mutations were assessed in blood donors, and the relationship with iron status was evaluated. Subjects (N = 542) were recruited at the Hemocentro da Santa Casa de São Paulo, São Paulo, Brazil. Iron status was not influenced by HFE mutations in women and was independent of blood donation frequency. In contrast, men carrying the HFE 282CY genotype had lower total iron-binding capacity (TIBC) than HFE 282CC genotype carriers. Men who donated blood for the first time and were carriers of the HFE 282CY genotype had higher transferrin saturation values and lower TIBC concentrations than those with the homozygous wild genotype for the HFE C282Y mutation. Moreover, in this group of blood donors, carriers of HFE 63DD plus 63HD genotypes had higher serum ferritin values than those with the homozygous wild genotype for HFE H63D mutation. Multiple linear regression analysis showed that HFE 282CY leads to a 17.21% increase (P = 0.018) and a 83.65% decrease (P = 0.007) in transferrin saturation and TIBC, respectively. In addition, serum ferritin is influenced by age (3.91%, P = 0.001) and the HFE 63HD plus DD genotype (55.84%, P = 0.021). In conclusion, the HFE 282Y and 65C alleles were rare, while the HFE 63D allele was frequent in Brazilian blood donors. The HFE C282Y and H63D mutations were associated with alterations in iron status in blood donors in a gender-dependent manner.


Assuntos
Doadores de Sangue , Antígenos de Histocompatibilidade Classe I/genética , Ferro/sangue , Proteínas de Membrana/genética , Mutação , Receptores da Transferrina/genética , Adulto , Feminino , Frequência do Gene , Genótipo , Proteína da Hemocromatose , Humanos , Masculino , Fatores Sexuais
3.
Transfus Med ; 19(5): 245-51, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19747287

RESUMO

Limited data are available about iron deficiency (ID) in Brazilian blood donors. This study evaluated the frequencies of ID and iron-deficiency anaemia (IDA) separately and according to frequency of blood donations. The protective effect of the heterozygous genotype for HFE C282Y mutation against ID and IDA in female blood donors was also determined. Five hundred and eight blood donors were recruited at the Blood Bank of Santa Casa in Sao Paulo, Brazil. Haemoglobin and serum ferritin concentrations were measured. The genotype for HFE C282Y mutation was determined by polymerase chain reaction followed by restriction fragment length polymorphism analysis. The ID was found in 21.1% of the women and 2.6% of the men whereas the IDA was found in 6.8 and 0.3%, respectively. The ID was found in 11.9% of the women in group 1 (first-time blood donors) and the frequency increased to 38.9% in women of the group 3 (blood donors donating once or more times in the last 12 months). No ID was found in men from group 1; however the ID frequency increased to 0.9% in group 2 (who had donated blood before but not in the last 12 months) and 5.0% in group 3. In summary, the heterozygous genotype was not associated with reduction of ID or IDA frequencies in both genders, but in male blood donors it was associated with a trend to elevated ferritin levels (P = 0.060). ID is most frequent in Brazilian women but was also found in men of group 3.


Assuntos
Anemia Ferropriva/genética , Doadores de Sangue/estatística & dados numéricos , Antígenos de Histocompatibilidade Classe I/genética , Deficiências de Ferro , Proteínas de Membrana/genética , Mutação Puntual , Adulto , Distribuição por Idade , Anemia Ferropriva/epidemiologia , Brasil , Feminino , Ferritinas/sangue , Testes Genéticos/estatística & dados numéricos , Genótipo , Proteína da Hemocromatose , Humanos , Masculino , Pessoa de Meia-Idade , Fatores Sexuais , Adulto Jovem
4.
Eur J Clin Nutr ; 62(8): 1010-21, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17522601

RESUMO

OBJECTIVES: To examine the association between methylenetetrahydrofolate reductase (MTHFR) (C677T and A1298C), methionine synthase (MTR) A2756G and methionine synthase reductase (MTRR) A66G gene polymorphisms and total homocysteine (tHcy), methylmalonic acid (MMA) and S-adenosylmethionine/S-adenosylhomocysteine (SAM/SAH) levels; and to evaluate the potential interactions with folate or cobalamin (Cbl) status. SUBJECTS/METHODS: Two hundred seventy-five healthy women at labor who delivered full-term normal babies. Cbl, folate, tHcy, MMA, SAM and SAH were measured in serum specimens. The genotypes for polymorphisms were determined by PCR-restriction fragment length polymorphism (RFLP). RESULTS: Serum folate, MTHFR 677T allele and MTR 2756AA genotypes were the predictors of tHcy levels in pregnant women. Serum Cbl and creatinine were the predictors of SAM/SAH ratio and MMA levels, respectively. The gene polymorphisms were not determinants for MMA levels and SAM/SAH ratios. Low levels of serum folate were associated with elevated tHcy in pregnant women, independently of the gene polymorphisms. In pregnant women carrying MTHFR 677T allele, or MTHFR 1298AA or MTRR 66AA genotypes, lower Cbl levels were associated with higher levels of tHcy. Lower SAM/SAH ratio was found in MTHFR 677CC or MTRR A2756AA genotypes carriers when Cbl levels were lower than 142 pmol/l. CONCLUSIONS: Serum folate and MTHFR C677T and MTR A2576G gene polymorphisms were the determinants for tHcy levels. The interaction between low levels of serum Cbl and MTHFR (C677T or A1298C) or MTRR A66G gene polymorphisms was associated with increased tHcy.


Assuntos
5-Metiltetra-Hidrofolato-Homocisteína S-Metiltransferase/genética , Ferredoxina-NADP Redutase/genética , Homocisteína/sangue , Metilenotetra-Hidrofolato Redutase (NADPH2)/genética , Polimorfismo de Fragmento de Restrição , Gravidez/sangue , Adolescente , Adulto , Alelos , Análise de Variância , Feminino , Ácido Fólico/sangue , Frequência do Gene , Genótipo , Humanos , Ácido Metilmalônico/sangue , Reação em Cadeia da Polimerase , Gravidez/genética , S-Adenosil-Homocisteína/sangue , S-Adenosilmetionina/sangue , Vitamina B 12/sangue , Adulto Jovem
5.
Arch Latinoam Nutr ; 51(1 Suppl 1): 42-7, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11688081

RESUMO

The relative effectiveness of daily supplementation of iron deficiency during pregnancy using 15 mg/day of iron from iron-bis-glycinate chelate (71 pregnant women), or 40 mg iron from ferrous sulfate (74 pregnant women) was evaluated by measuring hemoglobin, transferrin saturation and serum ferritin, at the beginning of the study (< 20 weeks of pregnancy) and at 20-30 weeks and 30-40 weeks thereafter. Ingestion for 13 weeks or more was considered adequate. Seventy three percent of the Ferrochel consuming group and 35% of the ferrous sulfate consuming group were considered to have taken the treatment adequately. The decrease in levels of all the measured parameters was significantly less pronounced in the group that consumed Ferrochel in spite of the lower treatment dose. Iron depletion was found in 30.8% of the women treated with Ferrochel and in 54.5% of the women than consumed ferrous sulfate. Of the factors responsible for non compliance taste was reported in 29.8% of the ferrous sulfate consumers and none in the groups that consumed Ferrochel. It is concluded that daily supplementation with Ferrochel was significantly more effective, in spite of the lower dose, than supplementation with ferrous sulfate.


Assuntos
Anemia Ferropriva/prevenção & controle , Compostos Ferrosos/uso terapêutico , Glicina/análogos & derivados , Glicina/uso terapêutico , Quelantes de Ferro/uso terapêutico , Complicações na Gravidez/prevenção & controle , Suplementos Nutricionais , Feminino , Ferritinas/sangue , Hemoglobinas/análise , Humanos , Deficiências de Ferro , Estudos Longitudinais , Gravidez , Estudos Prospectivos , Transferrina/análise , Resultado do Tratamento
6.
Rev Lat Am Enfermagem ; 9(3): 64-9, 2001 May.
Artigo em Espanhol | MEDLINE | ID: mdl-12040792

RESUMO

Nutritional conditions in the pre-gestacional period and during pregnancy were evaluated in 372 pregnant women based on the body mass index and Rosso's Graph. Approximately half (51%) the pregnant women presented normal pre-gestacional weight; however, 17.7% were underweight and 31.3% overweight. In the third trimester, 18.8% were underweight and 28.2% overweight. The weight at birth increased as nutritional conditions during pregnancy improved. These results show the importance of appropriate anthropometric control in order to prevent a bad neonatal prognosis and reaffirms the importance of such activity during the whole routine of pre-natal control.


Assuntos
Avaliação Nutricional , Estado Nutricional , Adolescente , Adulto , Brasil , Área Programática de Saúde , Feminino , Humanos , Gravidez , Estudos Prospectivos
7.
Rev Saude Publica ; 34(4): 421-6, 2000 Aug.
Artigo em Português | MEDLINE | ID: mdl-10973166

RESUMO

The assessment of iron status at individual and populational levels has been the target of many studies because some issues still need to be defined. A Medline, Lilacs and Dedalus literature review was carried out for the period of 1972 to 1998 and scientific publications in both English and Portuguese relating hematological and biochemical parameters were used in the assessment of iron status. The parameters reflect the three different stages of iron storage deficiency, which occur in a gradual and progressive way leading to the development of anaemia. In general, when used alone, these parameters are neither sensitive nor specific for detecting iron deficiency anaemia. Moreover, some advantages and limitations should be taken into consideration for the choice of the appropriate parameter. To improve both sensitivity and specificity, different parameters have been used in association and their specific contribution is determined according to the characteristics of the study population, methodological issues and the costs involved in the process.


Assuntos
Deficiências de Ferro , Estado Nutricional , Anemia Ferropriva/diagnóstico , Humanos , Ferro/sangue , Sensibilidade e Especificidade
8.
Braz J Med Biol Res ; 32(6): 683-7, 1999 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10412546

RESUMO

Erythrocyte membrane proteins from 44 representative mammals were studied. Protein 4.2 was not detected in guinea pigs (Cavia porcellus) (N = 14), Southern Brazilian swamp large rats (Myocastor coypus) (N = 2), cutias (Dasyprocta sp) (N = 4), and horses (Equus caballus) (N = 13). These animals also presented high ankyrin concentrations except for the horse which did not exhibit a sharp band, although minor components located between proteins 2 and 3 could account for the ankyrin family. The rodents studied did present band 6, which was not detectable in other common rodents such as white rats (Rattus norvegicus) (N = 9) and mice (Mus musculus) (N = 12). Since the absence of protein 4.2 does not disrupt the cytoskeleton membrane, we suggest that it is not an essential protein. Its absence may be compensated physiologically by the higher ankyrin concentration observed.


Assuntos
Proteínas do Citoesqueleto , Membrana Eritrocítica , Animais , Eritrócitos/citologia , Cobaias , Cavalos , Mamíferos , Ratos
9.
Braz. j. med. biol. res ; 32(6): 683-7, Jun. 1999. ilus
Artigo em Inglês | LILACS | ID: lil-233700

RESUMO

Erythrocyte membrane proteins from 44 representative mammals were studied. Protein 4.2 was not detected in guinea pigs (Cavia porcellus) (N = 14), Southern Brazilian swamp large rats (Myocastor coypus) (N = 2), cutias (Dasyprocta sp) (N = 4), and horses (Equus caballus) (N = 13). These animals also presented high ankyrin concentrations except for the horse which did not exhibit a sharp band, although minor components located between proteins 2 and 3 could account for the ankyrin family. The rodents studied did present band 6, which was not detectable in other common rodents such as white rats (Rattus norvegicus) (N = 9) and mice (Mus musculus) (N = 12). Since the absence of protein 4.2 does not disrupt the cytoskeleton membrane, we suggest that it is not an essential protein. Its absence may be compensated physiologically by the higher ankyrin concentration observed.


Assuntos
Animais , Cobaias , Ratos , Proteínas do Citoesqueleto , Membrana Eritrocítica , Eritrócitos/citologia , Cavalos , Mamíferos
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