Folate, vitamin B12 and Homocysteine status in the post-folic acid fortification era in different subgroups of the Brazilian population attended to at a public health care center.

BACKGROUND: Folate and vitamin B12 are essential nutrients, whose deficiencies are considerable public health problems worldwide, affecting all age groups. Low levels of these vitamins have been associated with high concentrations of homocysteine (Hcy) and can lead to health complications. Several genetic polymorphisms affect the metabolism of these vitamins. The aims of this study were to assess folate, vitamin B12 and homocysteine status in distinct Brazilian individuals after the initiation of folic acid fortification by Brazilian authorities and to investigate the effects of RFC1 A80G, GCPII C1561T and MTHFR C677T polymorphisms on folate, vitamin B12 and Hcy levels in these populations. METHODS: A total of 719 individuals including the elderly, children, as well as pregnant and lactating women were recruited from our health care center. Folate, vitamin B12 and Hcy levels were measured by conventional methods. Genotype analyses of RFC1 A80G, GCPII C1561T and MTHFR C677T polymorphisms were performed by PCR-RFLP. RESULTS: The overall prevalence of folate and vitamin B12 deficiencies were 0.3% and 4.9%, respectively. Folate deficiency was observed only in the elderly (0.4%) and pregnant women (0.3%), whereas vitamin B12 deficiency was observed mainly in pregnant women (7.9%) and the elderly (4.2%). Plasma Hcy concentrations were significantly higher in the elderly (33.6%). Pregnant women carrying the MTHFR 677TT genotype showed lower serum folate levels (p = 0.042) and higher Hcy levels (p = 0.003). RFC1 A80G and GCPII C1561T polymorphisms did not affect folate and Hcy levels in the study group. After a multivariate analysis, Hcy levels were predicted by variables such as folate, vitamin B12, gender, age and RFC1 A80G polymorphism, according to the groups studied. CONCLUSION: Our results suggest that folate deficiency is practically nonexistent in the post-folic acid fortification era in the subgroups evaluated. However, screening for vitamin B12 deficiency may be particularly relevant in our population, especially in the elderly.

Metals and (metallo)proteins identification in vitreous humor focusing on post-mortem biochemistry.

This work describes the evaluation of metals and (metallo)proteins in vitreous humor samples and their correlations with some biological aspects in different post-mortem intervals (1-7 days), taking into account both decomposing and non-decomposing bodies. After qualitative evaluation of the samples involving 26 elements, representative metal ions (Fe, Mg and Mo) are determined by inductively coupled plasma mass spectrometry after using mini-vial decomposition system for sample preparation. A significant trend for Fe is found with post-mortem time for decomposing bodies because of a significant increase of iron concentration when comparing samples from bodies presenting 3 and 7 days post-mortem interval. An important clue to elucidate the role of metals is the coupling of liquid chromatography with inductively coupled plasma mass spectrometry for identification of metals linked to proteins, as well as mass spectrometry for the identification of those proteins involved in the post-mortem interval.

Research on zinc blood levels and nutritional status in adolescents with autoimmune hepatitis.

CONTEXT: Zinc deficiency in children and adolescents impairs their growing, development and immune system. OBJECTIVES: To verify the existence of plasma and leukocyte zinc deficiency in adolescents with autoimmune hepatitis. METHODS: The study comprised 23 patients with autoimmune hepatitis, aged 10-18 years, assisted at the Ambulatory Service of Pediatric Hepatology of the University of Campinas Teaching Hospital, Campinas, SP, Brazil, and adolescents with ages compatible with the patients' ages comprised the control group. Sample of blood in both groups was collected for the analyses of plasma zinc and leukocyte zinc by atomic absorption spectrophotometry, beyond the nutritional status was evaluated in each adolescent. The following statistical tests were used: Mann-Whitney, Spearman's correlation and interclass concordance analysis. RESULTS: The significance level adopted was 5%. The average zinc level in plasma in patients was 71.91 ± 11.79 µg/dL and, in the control group, it was 80.74 ± 10.92 µg/dL, showing a significant difference (P = 0.04). The leukocyte zinc level in patients was 222.33 ± 166.13 pmol/106 cells and, in the control group, it was 226.64 ± 217.81 pmol/106 cells; there was no statistical significance between them (P = 0.45). CONCLUSION: The evaluation of the nutritional status showed that eutrophy is prevalent in patients, and they presented a higher body fat value than the control group, with a significant difference. More research is needed with adolescents with autoimmune hepatitis regarding levels of essential micronutrients, such as zinc, because a good nutritional status can improve the prognostic of liver disease.

Research on zinc blood levels and nutritional status in adolescents with autoimmune hepatitis / Investigação do nível de zinco sanguíneo e estado nutricional em adolescentes com hepatite autoimune

CONTEXT: Zinc deficiency in children and adolescents impairs their growing, development and immune system. OBJECTIVE: To verify the existence of plasma and leukocyte zinc deficiency in adolescents with autoimmune hepatitis. METHODS: The study comprised 23 patients with autoimmune hepatitis, aged 10-18 years, assisted at the Ambulatory Service of Pediatric Hepatology of the University of Campinas Teaching Hospital, Campinas, SP, Brazil, and adolescents with ages compatible with the patients' ages comprised the control group. Sample of blood in both groups was collected for the analyses of plasma zinc and leukocyte zinc by atomic absorption spectrophotometry, beyond the nutritional status was evaluated in each adolescent. The following statistical tests were used: Mann-Whitney, Spearman's correlation and interclass concordance analysis. RESULTS:The significance level adopted was 5 percent. The average zinc level in plasma in patients was 71.91 ± 11.79 µg/dL and, in the control group, it was 80.74 ± 10.92 µg/dL, showing a significant difference (P = 0.04). The leukocyte zinc level in patients was 222.33 ± 166.13 pmol/10(6) cells and, in the control group, it was 226.64 ± 217.81 pmol/10(6) cells; there was no statistical significance between them (P = 0.45). CONCLUSION:The evaluation of the nutritional status showed that eutrophy is prevalent in patients, and they presented a higher body fat value than the control group, with a significant difference. More research is needed with adolescents with autoimmune hepatitis regarding levels of essential micronutrients, such as zinc, because a good nutritional status can improve the prognostic of liver disease.

CONTEXTO: A deficiência de zinco em crianças ou adolescentes acarreta danos ao crescimento, desenvolvimento e ao sistema imune dos indivíduos. OBJETIVO: Verificar a existência de deficiência de zinco plasmático e/ou leucocitário em adolescentes com hepatite autoimune. MÉTODOS:Participaram do estudo 23 pacientes com hepatite autoimune entre 10 e 18 anos, atendidos no Ambulatório de Hepatologia Pediátrica do Hospital de Clínicas da UNICAMP - Campinas, SP e 23 adolescentes com idade pareada com os pacientes formaram o grupo controle. Foi coletada amostra de sangue de todos os pacientes e grupo controle para as análises de zinco plasmático e zinco leucocitário por meio da espectrofotometria de absorção atômica, além de ter sido verificado o estado nutricional de cada adolescente. Os testes estatísticos empregados foram o de Mann-Whitney, correlação de Spearman e análise de concordância interclasses. RESULTADOS: O nível de significância adotado foi de 5 por cento. A média de zinco plasmático nos pacientes foi de 71.91 ± 11.79 µg/dL e no grupo controle foi de 80.74 ± 10.92 µg/dL, essa diferença foi significante (P = 0.04). O nível de zinco leucocitário nos pacientes foi igual a 222.33 ± 166.13 pmol/10(6) células e no grupo controle foi de 226.64 ± 217.81 pmol/10(6) células, não ocorrendo diferença estatisticamente significante entre estes (P = 0.45). CONCLUSÃO: A avaliação do estado nutricional mostrou que a eutrofia é prevalente nos pacientes e estes possuem maior valor de gordura corporal que o grupo controle com diferença significativa. São necessárias mais pesquisas com adolescentes com hepatite autoimune em relação aos níveis de micronutrientes essenciais, como o zinco, pois um bom estado nutricional pode melhorar o prognóstico da doença hepática.

Synthesis and application of a peroxidase-like molecularly imprinted polymer based on hemin for selective determination of serotonin in blood serum.

This work reports the preparation of a molecularly imprinted polymer (MIP) for selective catalytic detection of serotonin (5-hydroxytryptamine, 5-HT). The process is based on the synthesis of polymers with hemin introduced as the catalytic center to mimic the active site of peroxidase. The copolymer MIP, containing artificial recognition sites for 5-HT, has been prepared by bulk polymerization using methacrylic acid (MAA) and hemin as the functional monomers, and ethylene glycol dimethacrylate (EGDMA) as the cross-linker. For the determination of 5-HT, a flow injection analysis system coupled to an amperometric detector was optimized using multivariate analysis. The effects of different parameters, such as pH, buffer flow rate, buffer nature, peroxide concentration and sample volume were evaluated. After optimizing the experimental conditions, a linear response range from 1.0 up to 1000.0 micromolL(-1) was obtained with a sensitivity of 0.4nA/ micromolL(-1). The detection limit was found to be 0.30 micromolL(-1), while the precision values (n=6) evaluated by relative standard deviation (R.S.D.) were, respectively, 1.3 and 1.7% for solutions of 50 and 750 micromolL(-1) of 5-HT. No interference was observed by structurally similar compounds (including epinephrine, dopamine and norepinephrine), thus validating the good performance of the imprinted polymer. The method was applied for the determination of 5-HT in spiked blood serum samples.

Estrogen receptor alpha and beta gene polymorphisms are not risk factors for recurrent miscarriage in a Brazilian population.

The aim of this study was to determine the prevalence of alpha (ESR1: c.454-397T>C and c.454-351A>G) and beta (ESR2: 1082G>A and 1730G>A) estrogen receptor gene polymorphisms in 2 Brazilian ethnic groups (Caucasian, African Brazilian) and to investigate their association with recurrent miscarriage (RM) in 75 women with a history of 3 or more consecutive pregnancy losses and 139 controls with at least 2 live births and no history of pregnancy loss. Polymerase chain reaction and restriction fragment length polymorphism were used to identify gene polymorphisms. Coagulation methods were used to measure protein C, protein S, and fibrinogen, and a chromogenic method was used for antithrombin quantification. Significantly higher prevalences of 1082G>A and 1730G>A polymorphisms were seen in African Brazilian and Caucasian controls, respectively. There was no association between RM and ESR polymorphisms. There was a difference in the genotype prevalence in the c.454-39T>C polymorphism between RM and control Caucasians, but this finding was not associated with an increased risk of miscarriage. There was no synergistic or additive effect between ESR polymorphisms and thrombophilia in RM patients. A difference in the prevalence of ESR polymorphisms was observed, according to ethnic origin. ESR polymorphisms could not be considered a risk factor for RM.

Effects of a one-week treatment with acid gastric inhibitors on Helicobacter pylori-infected mice.

OBJECTIVE: Antiacid drugs, including omeprazole and ranitidine, were prescribed to Helicobacter pylori-infected subjects in combination with antibiotics during eradication treatment. Several reports suggest that these drugs have additional pharmacological properties, such as antineutrophil, antiapoptotic and antioxidant characteristics. The aim of this work was to study the effects of acid suppressive medication treatment in the H. pylori infection experimental model, focusing on possible additional pharmacological properties. MATERIAL AND METHODS: The ability of gastric acid suppression was assessed in pylorus-ligated animals. Gastric H. pylori colonization levels, myeloperoxidase (MPO) acitivity, macroscopic damage, Bax and Bcl-2 expression and DNA damage levels were assessed in C57BL/6-infected mice after treatment for one week with omeprazole (100 mg kg(-1)) or ranitidine (100 mg kg(-1)). RESULTS: Omeprazole treatment increased bacteria colonization and MPO activity in mice stomachs. Both antiacid drugs efficiently improved macroscopic damage, although only omeprazole restored the expression of the antiapoptotic Bcl-2 protein in gastric mucosa of infected animals. CONCLUSIONS: Some additional omeprazole-related properties, such as antineutrophil properties, were not observed in H. pylori-infected mice after one week of treatment, suggesting that this property is restricted to in vitro approaches. However, the antiapoptotic activity of omeprazole could be attributed to an ability to modify the protein expression of Bcl-2, decreased by H. pylori infection.

Optimized hyperventilation preserves 2,3-diphosphoglycerate in severe traumatic brain injury.

INTRODUCTION: The concentration of 2,3-diphosphoglycerate (2,3-DPG/Hct) increases as a physiological occurrence to pH increase and hyperventilation. This response was tested in patients with severe traumatic brain injury (TBI). METHOD: The concentration of 2,3-DPG/Hct was measured daily for six days in eleven patients with severe TBI in need of optimized hyperventilation because of intracranial hypertension. RESULTS: There was correlation between pH and the concentration of DPG/Hct. The concentration of 2,3-DPG/Hct remained predominantly within normal levels with slight increase in the sixth day of the study. The concentration of 2,3-DPG/Hct correlated significantly with measured partial pressure of oxygen that saturates 50% the hemoglobin of the blood (P50st), confirming the consistency of our data. CONCLUSION: The expected physiological response of a progressive increase in concentration of 2,3-DPG/Hct to hyperventilation was not observed. This fact may be explained by the intermittent and not sustained hyperventilation as dictated by the protocol of optimized ventilation.

Optimized hyperventilation preserves 2,3-diphosphoglycerate in severe traumatic brain injury

INTRODUCTION: The concentration of 2,3-diphosphoglycerate (2,3-DPG/Hct) increases as a physiological occurrence to pH increase and hyperventilation. This response was tested in patients with severe traumatic brain injury (TBI). METHOD: The concentration of 2,3-DPG/Hct was measured daily for six days in eleven patients with severe TBI in need of optimized hyperventilation because of intracranial hypertension. RESULTS:There was correlation between pH and the concentration of DPG/Hct. The concentration of 2,3-DPG/Hct remained predominantly within normal levels with slight increase in the sixth day of the study. The concentration of 2,3-DPG/Hct correlated significantly with measured partial pressure of oxygen that saturates 50 percent the hemoglobin of the blood (P50st), confirming the consistency of our data. CONCLUSION: The expected physiological response of a progressive increase in concentration of 2,3-DPG/Hct to hyperventilation was not observed. This fact may be explained by the intermittent and not sustained hyperventilation as dictated by the protocol of optimized ventilation.

INTRODUÇÃO: A concentração de 2,3-difosfoglicerato nos eritrócitos (2,3-DPG/Hct) aumenta como ocorrência fisiológica ao aumento do pH e à hiperventilação. Esta resposta foi testada em pacientes com traumatismo craniencefálico (TCE) grave. MÉTODO: A concentração de 2,3-DPG/Hct foi medida diariamente, durante seis dias, em 11 pacientes com TCE grave necessitando de hiperventilação otimizada por causa da hipertensão intracraniana. RESULTADOS: Houve correlação entre o pH e a concentração de 2,3-DPG/Hct. A concentração de 2,3-DPG/Hct permaneceu predominantemente dentro da normalidade, com ligeira tendência à elevação no sexto dia de estudo. Houve correlação entre a concentração de 2,3-DPG/Hct e a pressão parcial de oxigênio que satura 50 por cento da hemoglobina (P50st), confirmando a consistência dos dados. CONCLUSÃO: A esperada resposta fisiológica de aumento progressivo da concentração de 2,3-DPG/Hct não foi observada. Este fato pode ser explicado pela aplicação intermitente e não sustentada de hiperventilação, como ditado pelo protocolo clínico de ventilação otimizada.

Association between estrogen receptor alpha and beta gene polymorphisms and deep vein thrombosis.

BACKGROUND: Estrogen and the estrogen receptors alpha (ESR1) and beta (ESR2) play a role in regulating genes, including coagulation and fibrinolysis genes. OBJECTIVE: We investigated the association between ESR1 c.454-397T>C and c.454-351A>G and ESR2 1082A>G and 1730A>G polymorphisms and the risk of deep vein thrombosis (DVT), in 134 patients and 134 controls with acquired risk factors for thrombosis associated with estrogen alterations, such as pregnancy, puerperium, oral contraceptives (OC), and hormone replacement therapy (HRT). We also analysed 134 men with DVT. We investigated the relationship of these polymorphisms and the levels of fibrinogen, protein C (PC), protein S (PS), and antithrombin (AT) activity. METHODS: Gene polymorphisms were identified by using PCR and RFLP. Coagulation methods were used to measure PC, PS, and fibrinogen. Chromogenic methods were used to quantify AT. RESULTS AND CONCLUSIONS: The presence of the AA genotype of the 1730G>A polymorphism (OR=0.18; 95%CI=0.05-0.62) suggests a protective effect for DVT in women using OC. As the GG genotype of the 1730G>A polymorphism is associated with increased PS activity in all control women and women using OC, this suggested that a protective effect must occur by another pathway not related to PS. The AA and AG genotypes of the c.454-351A>G and GG genotype of the 1082G>A polymorphisms are associated with increased fibrinogen concentration in pregnant women. The GG haplotype in the ESR2 gene (P<0.001) was related to factor V Leiden or G20210A mutation in the prothrombin gene, or both, as predictive factors of DVT.

Determination of glutathione in hemolysed erythrocyte with amperometric sensor based on TTF-TCNQ.

BACKGROUND: GSH has a relevant role in human metabolism as an indicator of disease risks. An amperometric sensor for glutathione (GSH) determination is described as an alternative method featuring simple construction procedure and short time analysis. METHOD: The developed sensor was used to determine glutathione at low potential using a TTF-TCNQ complex. RESULTS: The sensor exhibits a linear response range from 5 to 340 micromol/l under applied potential of 200 mV vs. SCE. The sensitivity and detection limit were 90.1 microA l/mmol cm(2) and 0.3 micromol/l, respectively. CONCLUSION: When the sensor was tested in hemolysed erythrocyte samples for GSH determination, a good correlation in results was observed between the sensor and the spectrophotometric method. The sensor showed recovery values between 98% and 102%.

Polymorphisms in the methylenetetrahydrofolate reductase and methionine synthase reductase genes and homocysteine levels in Brazilian children.

Hyperhomocysteinemia is a risk factor for thrombosis, and methylenetetrahydrofolate reductase (MTHFR) and methionine synthase reductase (MTRR) polymorphisms, folate, and B12 levels could contribute to plasma homocysteine (Hcy) variation. Although well established in adults, few studies have been performed in childhood. In this study, we investigated association of polymorphisms C677T and A1298C in the MTHFR gene and A66G in the MTRR gene with Hcy levels in children. These polymorphisms, as well as Hcy, folate, and vitamin B12 levels were investigated in 220 normal children with ages ranging from 1 to 8 years. Plasma Hcy, folate, and vitamin B12 levels were normal in all children. None of the polymorphisms could be considered an independent risk factor for hyperhomocysteinemia during childhood. The median Hcy levels in 37 children (17%) doubly heterozygous for C677T and A1298C mutations in the MTHFR gene were not different from the other genotypes. However, the association of the different genotypes with Hcy, folate, and vitamin B12 levels demonstrated significant P-values. The folate levels demonstrated a statistically significant decrease (P = 0.0477) from the C677T mutation in the MTHFR gene (TT genotype) when compared to the other groups. Folate was the only independent risk factor for hyperhomocysteinemia. Thus, monitoring the concentrations of folate would be more helpful for evaluating hyperhomocysteinemia and for preventing cardiovascular disease.

Derterminação de íon cálcio em fluido biológico utilizando análise por injeção em fluxo com eletrodo tubular / Dertemination of calcium ion in biological fluid using flow injection analysis With a tubular electrode

Neste trabalho é descrito um método utilizando análises por injeção em fluxo (FIA), desenvolvido para medir concentrações de íon cálcio. Desta maneira as condições analíticas do sistemas foram investigadas e utilizadas para determinaçao do íon em soro sangüineo. A performance do sistema FIA acoplado ao eletrodo tubular construído foi avaliada e a precisão expressa como sendo a estimativa do desvio padrão relativo (1,4 por cento). A faixa linear de resposta foi de 1,0 10-5 a 1,010-2 mol L-1, com inclinação de 25,8 mV e limite de detecção de 7,9 10-6 mol L-1 HEPES (ph6). A freqüência analítica observada para o sistema foi de 50 amostras/h. O eletrodo apresentou uma seletividade para cálcio na presença dos seguintes íons interferentes: mg2+, Ba2+ Na+ e K+, apresentando valores de K pot de 7,51 10-3; 5,30 10-3., 0,88 10-3 e1,51 10-3, respectivamente. Os resultados para a determinação de íon cálcio nas amostras de soro sangüinio, pelo método descrito no presente trabalho, apresentaram uma diferença média relativa de 6,6 por cento quando comparado com o método de referência.