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.

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. 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. 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. 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.141

Antioxidant system involving the glutathione metabolic cycle associated to electroanalytical methods in the oxidative stress evaluation

The most relevant advances on the analytical applications of glutathione determination based on glutathione redox cycle and the antioxidant system are given. The main enzymes that participate of the glutathione metabolism are the glutathione peroxidase and glutathione reductase. The glutathione peroxidase has a major role in the removal of hydrogen peroxide and lipid peroxides from the cells. These enzymes, operating in tandem with catalase and superoxide dismutase promote a scavenging of oxyradical products in tissues minimizing damages caused by these species. Reduced glutathione is the major intracellular thiol found in mammals and changes in the glutathione concentration in biological fluids or tissues may provide a useful marker in certain disorders like hemolytic anemia, myocardial oxidative stress and in the investigation of some kinds of cancers. Particular attention is devoted to the main advantages supplied by biosensors in which there is an incorporation of bioactive materials for the glutathione determination. The correlation between stability and sensitivity of some reduced glutathione electrochemical sensors is discussed.112119Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP

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.631170-

Optimized hyperventilation preserves 2,3-diphosphoglycerate in severe traumatic brain injury A hiperventilação otimizada preserva o 2,3-difosfoglicerato no traumatismo craniencefálico grave

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.<br>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% 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

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.128A256-6

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.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 bodies61018011807Palmiere, C., Mangin, P., Postmortem chemistry update part II-Review (2012) J. Leg. Med., 126, pp. 199-215Chandrakanth, H.V., Kanchan, T., Balaraj, B.M., Virupaksha, H.S., Chandrashekar, T.N., Postmortem vitreous chemistry-An evaluation of sodium, potassium and chloride levels in estimation of time since death (during the first 36 h after death) (2012) J. For. Legal Med., 19, pp. 1-6Maeda, H., Ishikawa, T., Michiue, T., Forensic biochemistry for functional investigation of death: Concept and practical application (2011) Leg. Med., 13, pp. 55-67Barnett, J.P., Scanlan, D.J., Blindauer, C.A., Protein fractionation and detection for metalloproteomics: Challenges and approaches (2012) Anal. Bioanal. Chem., 402, pp. 3311-3322Mounicou, S., Szpunar, J., Lobinski, R., Metallomics: The concept and methodology (2009) Chem. Soc. Rev., 38, pp. 1119-1138Ugarte, M., Grime, G.W., Lord, G., Geraki, K., Collingwood, J.F., Finnegan, M.E., Farnfield, H., Osborne, N.N., Concentration of various trace elements in the rat retina and their distribution in different structures (2012) Metallomics, 4, pp. 1245-1254Thierauf, A., Musshoff, F., Madea, B., Post-mortem biochemical investigation of vitreous humor (2009) Forensic Sci. Int., 192, pp. 78-82Madea, B., Musshoff, F., Postmortem biochemistry (2007) Forensic Sci. Int., 165, pp. 165-171Sanches, L.R., Seulin, S.C., Leyton, V., Paranhos, B.A.P.B., Pasqualucci, C.A., Muñoz, D.R., Osselton, M.D., Et al., Determination of opiates in whole blood and vitreous humor: A study of the matrix effect and an experimental design to optimize conditions for the enzymatic hydrolysis of glucuronides (2012) J. Anal. Toxicol., 36, pp. 162-170Muñoz-Barús, J.I., Lendoiro, E., Cordeiro, C., Rodríguez-Calvo, M.S., Veira, D.N., Suárez-Peñaranda, J.M., López-Rivadulla, M., Applications of Tandem Mass Spectrometry (LC-MSMS) in estimating the post-mortem interval using the biochemistry of the vitreous humour (2012) Forensic Sci. Int., 223, pp. 160-164Mihailovic, Z., Atanasijevic, T., Popovic, V., Milosevic, M.B., Sperhake, J.P., Estimation of the Postmortem Interval by Analyzing Potassium in the Vitreous Humor Could Repetitive Sampling Enhance Accuracy? (2012) Am. J. Forensic Med. Pathol., 33, pp. 400-403Angi, M., Kalirai, H., Coupland, S.E., Damato, B.E., Semeraro, F., Romano, M.R., Proteomic Analyses of the Vitreous Humour-Review (2012) Mediators Inflammation, 2012, pp. 1-7Tumram, N.K., Bardale, R.V., Dongre, A.P., Postmortem analysis of synovial fluid and vitreous humour for determination of death interval: A comparative study (2011) Forensic Sci. Int., 204, pp. 186-190Margalho, C., Franco, J., Corte-Real, F., Vieira, D.N., Illicit drugs in alternative biological specimens: A case report (2011) J. For. Legal Med., 18, pp. 132-135Soltyszewski, I., Janica, A.N., Pepiński, W., Spólnicka, M., Zbiec, R., Janica, J., Vitreous humour as a potential DNA source for postmortem human identification (2007) Folia Histochem. Cytobiol., 45, pp. 135-136Lang, G.K., Ophthamology: A Pocket Textbook Atlas (2006) Thieme, 2, pp. 287-289Sussulini, A., Banzato, C.E.M., Arruda, M.A.Z., Exploratory analysis of the serum ionomic profile for bipolar disorder and lithium treatment (2011) Int. J. Mass Spectrom., 307, pp. 182-184Nowak, R., Balabanova, S., Determination of calcium and magnesium in postmortem human vitreous humor as a test to ascertain the cause and time of death (1989) Z. Rechtsmed., 102, pp. 179-183Balabanova, S., Gras, V., Forensic value of phenobarbital, calcium and magnesium determination in vitreous humor (1992) Arch. Kriminol., 189, pp. 48-55Wheeler, M.S., Butts, J.D., Hudson, P., Vitreous humor magnesium in alcoholics (1983) Am. J. Forensic Med. Pathol., 4, pp. 105-110Farmer, J.G., Benomran, F., Watson, A.A., Harland, W.A., Magnesium, potassium, sodium and calcium in post-mortem vitreous humour from humans (1985) Forensic Sci. Int., 27, pp. 1-13Yamaguchi, Y., Matsumura, T., Ichida, K., Okamoto, K., Nishino, T., Human Xanthine Oxidase Changes its Substrate Specificity to Aldehyde Oxidase Type upon Mutation of Amino Acid Residues in the Active Site: Roles of Active Site Residues in Binding and Activation of Purine Substrate (2007) J. Biochem., 141, pp. 513-524Salam, H.F.A., Shaat, E.A., Aziz, M.H.A., Sheta, A.A.M., Hussein, H.A.S.M., Estimation of postmortem interval using thanatochemistry and postmortem changes (2012) Alex. J. of Med., 48, pp. 335-344McGahan, M.C., Fleisher, L.N., A micromethod for the determination of iron and total iron-binding capacity in intraocular fluids and plasma using electrothermal atomic absorption spectroscopy (1986) Anal. Biochem., 156, pp. 397-402McGahan, M.C., Fleisher, L.N., Inflammation-induced changes in the iron concentration and total iron-binding capacity of the intraocular fluids of rabbits (1986) Graefe's Arch. Clin. Exp. Ophthalmol., 226, pp. 27-30Beazley, K.E., Nurminskaya, M., Talbot, C.J., Linsenmayer, T.F., Corneal epithelial nuclear ferritin: Developmental regulation of ferritin and its nuclear transporter ferritoid (2008) Dev. Dyn., 237, pp. 2529-2541Goralska, M., Ferrell, J., Harned, J., Lall, M., Nagar, S., Fleisher, L.N., McGahan, M.C., Iron metabolism in the eye: A review (2009) Exp. Eye Res., 88, pp. 204-215Lu, J., Stewart, A.J., Sadler, P.J., Pinheiro, T.J., Blindauer, C.A., Albumin as a zinc carrier: Properties of its high-affinity zinc-binding site (2008) Biochem. Soc. Trans., 36, pp. 1317-1321Oettl, K., Reibnegger, G., Schmut, O., The redox state of human serum albumin in eye diseases with and without complications (2011) Acta Ophthalmol., 89, pp. 174-179Fukuda, M., Fullard, R.J., Willcox, M.D., Baleriola-Lucas, C., Bestawros, F., Sweeney, D., Fibronectin in the tear film (1996) Invest. Ophthalmol. Visual Sci., 37, pp. 459-46