Guettarda uruguensis (Rubiaceae): antioxidant and anti-inflammatory plant with quercetin and esters of p-coumaric acid.

Guettarda (Rubiaceae) is a genus known for its diverse range of bioactive compounds, with demonstrated anti-inflammatory and antioxidant properties. Guettarda uruguensis Cham. & Schltdl., commonly known as 'jasmim uruguaio' or 'veludinho,' is a native species of the Atlantic Forest that get interested in its potential therapeutic applications. In this study, we evaluated the phenolic content and antioxidant activity of the crude ethanol extract obtained from G. uruguensis leaves (EBGF) and fractions, as well as the antinociceptive, anti-inflammatory, and toxicity activity of the EBGF. Our findings revealed that the EBGF and its fractions contain polyphenolic compounds, including long-chain esters of p-coumaric acid and quercetin, which contribute to their potent antioxidant activity. The EBGF exhibited significant anti-inflammatory and antinociceptive effects, highlighting its potential as a natural product for treating pain and inflammation. Our study supports G. uruguensis as a promising source of bioactive compounds with pharmacological potential.

In vitro anti-inflammatory effects of vitamin D supplementation may be blurred in hemodialysis patients.

OBJECTIVES: This study aimed to evaluate the potential anti-inflammatory effects of vitamin D supplementation under uremic conditions, both in vivo and in vitro, and its effects on the parameters of mineral metabolism. METHODS: Thirty-two hemodialysis patients were randomly assigned to receive placebo (N=14) or cholecalciferol (N=18) for six months. Serum levels of calcium, phosphate, total alkaline phosphatase, intact parathyroid hormone (iPTH), and vitamin D were measured at baseline and after three and six months. The levels of fibroblast growth factor-23 (FGF-23), interleukin-1ß (IL-1ß), and high-sensitivity C-reactive protein (hs-CRP) were also measured at baseline and at six months. Human monocytes were used for in vitro experiments and treated with cholecalciferol (150 nM) and uremic serum. Cell viability, reactive oxygen species (ROS) production, and cathelicidin (CAMP) expression were evaluated using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, dichloro-dihydro-fluorescein diacetate assay, and real time-quantitative polymerase chain reaction, respectively. RESULTS: Both patient groups were clinically and biochemically similar at baseline. After six months, the levels of vitamin D and iPTH were higher and lower, respectively, in the cholecalciferol group than in the placebo group (p<0.05). There was no significant difference between the parameters of mineral metabolism, such as IL-1ß and hs-CRP levels, in both groups. Treatment with uremic serum lowered the monocyte viability (p<0.0001) and increased ROS production (p<0.01) and CAMP expression (p<0.05); these effects were counterbalanced by cholecalciferol treatment (p<0.05). CONCLUSIONS: Thus, cholecalciferol supplementation is an efficient strategy to ameliorate hypovitaminosis D in hemodialysis patients, but its beneficial effects on the control of secondary hyperparathyroidism are relatively unclear. Even though cholecalciferol exhibited anti-inflammatory effects in vitro, its short-term supplementation was not effective in improving the inflammatory profile of patients on hemodialysis, as indicated by the IL-1ß and hs-CRP levels.

Effect of watercress extract supplementation on lipid profile and oxidative stress markers in overweight people with physical disability: A randomized, double-blind, and placebo-controlled trial.

Studies have demonstrated that diet rich in cruciferous vegetables of the Brassicaceae family can reduce the risk of cardiovascular diseases and oxidative stress levels. Nasturtium officinale (Brassicaceae), commonly known as watercress is a perennial dicotyledonous plant usually found close to water. Although previous investigations have demonstrated the beneficial effects of watercress on hypercholesterolemia in animal studies, until now no such studies have been conducted with humans, up to this time. This study aimed to investigate whether overweight individuals were able to improve or maintain their serum lipid and oxidative stress markers when given standardized extract of Nasturtium officinale (SENO) as a supplement. This was a randomized, double-blind, and placebo-controlled trial conducted over 5 weeks. Thirty-four overweight people with physical disabilities were selected randomly to participate in this study and then they were assigned randomly to two groups, one treated with 750 mg//kg/d of SENO and the other treated with 750 mg/kg/d of placebo. The results indicated that SENO caused a significant improvement in the levels of low-density lipoprotein cholesterol, creatinine, and lipid peroxidation. However, SENO did not cause a significant statistical change in total serum cholesterol, triacylglycerol, and high-density lipoprotein levels; catalase, superoxide dismutase, creatinine, alanine aminotransferase, aspartate aminotransferase, and urea parameters. The present data might provide supportive evidence that SENO did not cause any harm and positively affected low-density lipoprotein cholesterol profile and creatinine as well as lipid peroxidation levels in the participants. Nevertheless, further studies are suggested to clarify the results presented in this clinical trial.

In vitro anti-inflammatory effects of vitamin D supplementation may be blurred in hemodialysis patients

OBJECTIVES: This study aimed to evaluate the potential anti-inflammatory effects of vitamin D supplementation under uremic conditions, both in vivo and in vitro, and its effects on the parameters of mineral metabolism. METHODS: Thirty-two hemodialysis patients were randomly assigned to receive placebo (N=14) or cholecalciferol (N=18) for six months. Serum levels of calcium, phosphate, total alkaline phosphatase, intact parathyroid hormone (iPTH), and vitamin D were measured at baseline and after three and six months. The levels of fibroblast growth factor-23 (FGF-23), interleukin-1β (IL-1β), and high-sensitivity C-reactive protein (hs-CRP) were also measured at baseline and at six months. Human monocytes were used for in vitro experiments and treated with cholecalciferol (150 nM) and uremic serum. Cell viability, reactive oxygen species (ROS) production, and cathelicidin (CAMP) expression were evaluated using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, dichloro-dihydro-fluorescein diacetate assay, and real time-quantitative polymerase chain reaction, respectively. RESULTS: Both patient groups were clinically and biochemically similar at baseline. After six months, the levels of vitamin D and iPTH were higher and lower, respectively, in the cholecalciferol group than in the placebo group (p<0.05). There was no significant difference between the parameters of mineral metabolism, such as IL-1β and hs-CRP levels, in both groups. Treatment with uremic serum lowered the monocyte viability (p<0.0001) and increased ROS production (p<0.01) and CAMP expression (p<0.05); these effects were counterbalanced by cholecalciferol treatment (p<0.05). CONCLUSIONS: Thus, cholecalciferol supplementation is an efficient strategy to ameliorate hypovitaminosis D in hemodialysis patients, but its beneficial effects on the control of secondary hyperparathyroidism are relatively unclear. Even though cholecalciferol exhibited anti-inflammatory effects in vitro, its short-term supplementation was not effective in improving the inflammatory profile of patients on hemodialysis, as indicated by the IL-1β and hs-CRP levels.

Biomarkers of oxidative stress and inflammation in people witha physical disability treated with a standardized extract of Nasturtium officinale: A randomized, double-blind, and placebo-controlled trial.

It is well established that plants from the Brassicaceae family, particularly watercress, have been associated to reduce oxidative DNA damage. Nasturtium officinale R. Br (watercress) contains glucosinolates, with anti-inflammatory action and protective effect on human health against oxidative stress. We aimed to evaluate whether the standardized extract of Nasturtium officinale (SENO) is capable of changing biomarkers of oxidative stress and inflammation in people with physical disabilities. 65 people enrolled this study: as a control group composed by; 15 people with no physical disability assessed once, 25 people with physical disabilities using 750 mg/kg/day of SENO, and 25 people with physical disabilities using 750 mg/kg/day of placebo-control for 5 weeks. Biomarkers of oxidative stress and inflammation were analyzed on day 0 and 36. The results indicated that SENO was associated with decreasing levels of lipid peroxidation, protein carbonyl, catalase, superoxide dismutase, and C-reactive protein. Furthermore, the cytokine kit demonstrated below and out of invertible range, which was impossible to detect the inflammatory process. Despite the cytokine kit was not able to detect the inflammation; these data might provide supportive evidence that SENO, have affected positively people with physical disabilities decreasing their biomarkers of oxidative stress and C-reactive protein. Further studies are required.

Data for serum 1,5 anhydroglucitol concentration in different populations.

1,5 anhydroglucitol (1,5-AG), is a nonmetabolized 1-deoxy form of glucose, originate mainly from the diet. 1,5-AG is a biomarker to detect and magnify hyperglycemic excursions (postprandial hyperglycemia) in diabetic patients. Concentrations of 1,5-AG has been applied as supporting biomarker to diagnosis of the major forms of diabetes (type 1, type 2, and gestational). The serum 1,5-AG reference interval is relevant to the appropriate clinical application of this biomarker. This article contains data regards to serum concentration of the biomarker primarily for healthy subjects, capture from the literature, in different populations. Correlation analysis between 1,5-AG and markers associated with diabetes and its complication were presented. The data was complementary to the study "Reference intervals for serum 1,5-anhydroglucitol in children, adolescents, adults, and pregnant women" (Welter et al., 2018). The data present in this article improve the comparisons for 1,5-AG in different conditions and methodologies.

Reference intervals for serum 1,5-anhydroglucitol in children, adolescents, adults, and pregnant women.

BACKGROUND: 1,5-anhydroglucitol (1,5-AG) is a validated marker of short-term glycemic control. We determined the reference intervals of 1,5-AG in different age groups and during pregnancy. METHODS: Blood samples were collected from 2303 Euro-Brazilian healthy subjects: 580 children, 496 adolescents, 922 adults matched by age and sex, and 305 pregnant women in four gestational periods. Serum 1,5-AG was measured using an enzymatic reagent in an automated system. RESULTS: The calculated reference intervals (nonparametric, 2.5th-97.5th) for males and females were, respectively: children, 96-302 and 89-277 µmol/l; adolescents, 84-311 and 79-277 µmol/l; and adults, 80-260 and 62-241 µmol/l. Males consistently showed significantly higher concentrations than females. 1,5-AG reference intervals in pregnant women were 56-298 µmol/l at <23 weeks gestation (n = 110), 37-166 µmol/l at 24-28 weeks gestation (n = 106), 34-155 µmol/l at 29-32 weeks gestation (n = 52), and 33-246 µmol/l at >32 weeks gestation (n = 37). No significant differences in 1,5-AG concentration were observed between non-pregnant and pregnant women at <23 weeks of gestation. A negative correlation (r = -0.287; p < .001) between 1,5-AG concentration and age was observed. CONCLUSIONS: The reference intervals for 1,5-AG were affected by sex and age.

Prevalence of anemia in schools of the metropolitan region of Curitiba, Brazil.

BACKGROUND: Anemia during childhood is one of the biggest public health problems worldwide, including Brazil. Insufficient or abnormal production of hemoglobin, loss of iron and excessive destruction of red blood cells are the most common causes of anemia. Among the reasons of anemia, iron deficiency accounts for 50% of anemia cases in developing countries. Affected individuals present a wide range of clinical problems, including delayed neuropsychomotor progression, impaired cellular immunity and reduction of intellectual capacity. This study aimed to evaluate the prevalence of anemia in children attending public schools in the metropolitan region of Curitiba, Paraná, Brazil. METHOD: A retrospective study was conducted of 409 children aged 8-12 years old included in an extension project of the Universidade Federal do Paraná. The results of complete blood count and hemoglobin electrophoresis of all children were evaluated. Anemia was considered when the hemoglobin levels were <11.5 g/dL. RESULTS: The prevalence of anemia was found to be 2.2% of the population studied, with hypochromic microcytic anemia being the most common type. Seven children had sickle cell trait and one had ß-thalassemia. CONCLUSION: The prevalence of anemia in this study was considered normal according the World Health Organization classification, which is different from the data found in other Brazilian regions.

Prevalence of anemia in schools of the metropolitan region of Curitiba, Brazil

ABSTRACT Background: Anemia during childhood is one of the biggest public health problems worldwide, including Brazil. Insufficient or abnormal production of hemoglobin, loss of iron and excessive destruction of red blood cells are the most common causes of anemia. Among the reasons of anemia, iron deficiency accounts for 50% of anemia cases in developing countries. Affected individuals present a wide range of clinical problems, including delayed neuropsychomotor progression, impaired cellular immunity and reduction of intellectual capacity. This study aimed to evaluate the prevalence of anemia in children attending public schools in the metropolitan region of Curitiba, Paraná, Brazil. Method: A retrospective study was conducted of 409 children aged 8-12 years old included in an extension project of the Universidade Federal do Paraná. The results of complete blood count and hemoglobin electrophoresis of all children were evaluated. Anemia was considered when the hemoglobin levels were <11.5 g/dL. Results: The prevalence of anemia was found to be 2.2% of the population studied, with hypochromic microcytic anemia being the most common type. Seven children had sickle cell trait and one had β-thalassemia. Conclusion: The prevalence of anemia in this study was considered normal according the World Health Organization classification, which is different from the data found in other Brazilian regions.

Anticoagulant Choices Affect the Mean Platelet Volume Measurement by Impedance.

BACKGROUND: Mean platelet volume (MPV) is a parameter that evaluates the platelet size. Clinical applications of MPV are limited because of its poor standardization in routine laboratories. This study analyzed the effect of anticoagulants on MPV measurements by impedance technology. METHODS: Blood from 36 healthy volunteers was collected in vacuum tubes filled with K2EDTA and sodium citrate, analyzed immediately (basal) and at 1, 2, and 3 hours after venipuncture. RESULTS: Comparisons between the anticoagulants demonstrated a significant difference (p < 0.05) after 1 hour of exposure with K2EDTA, causing a time-dependent increase on MPV measured. No significant changes in MPV were observed with sodium citrate with 3 hours of exposure (p > 0.05). CONCLUSIONS: The use of sodium citrate is highly indicated for assessment of MPV when the measurement time after blood collection is estimated to be more than 1 hour.

Incidence of factor VIII inhibitory antibodies in patients with hemophilia A seen at HEMOCE, Ceará, Brazil / Prevalência de inibidores do fator VIII em pacientes com hemofilia A atendidos no HEMOCE, Ceará, Brasil

ABSTRACT Introduction: Hemophilia A is an inherited disease caused by a deficiency of factor VIII, which results from a genetic inheritance located on the X chromosome. During treatment of patients with this disorder, factor VIII inhibitors may be present, which are primarily antibodies type immunoglobulin G (IgG), and interfere with the activation of factor VIII. Objectives: The present study aims to investigate and quantify the presence of antibodies against factor VIII:C in patients with hemophilia A, treated at the Ceará Hematology Center (HEMOCE). Material and methods: Screening for the inhibitor against factor VIII was performed according to the original Bethesda method or the Nijmegen modified assay. Results: One hundred eighty-four patients with hemophilia A were evaluated, from November 2012 to February 2015. From the patients evaluated, 149 (80.98%) showed no inhibitor presence, while in 35 patients (19.02%) the presence of the inhibitor was detected. Among inhibitor carriers, most hemophilia patients had high titers of the inhibitor (57.2%). Conclusion: The high incidence of factor VIII inhibitor in the study population can be explained by the type of treatment used at HEMOCE, which is based on the factor VIII in its recombinant form. The results should be evaluated carefully, so that the treatment and monitoring of these patients are conducted in the safest way possible.

RESUMO Introdução: A hemofilia A é uma doença hereditária causada pela deficiência do fator VIII, resultante de uma herança genética ligada ao cromossomo X. Durante o tratamento de pacientes com essa doença, pode ocorrer presença de inibidores do fator VIII, os quais são, em sua maioria, anticorpos do tipo imunoglobulina da classe G (IgG), que interferem na ativação do fator VIII. Objetivos: O presente estudo tem como objetivo pesquisar e quantificar a presença de anticorpos contra o fator VIII:C em pacientes com hemofilia A, atendidos no Hemocentro Ceará (HEMOCE). Material e métodos: A pesquisa para detecção do inibidor do fator VIII foi realizada de acordo com a modificação do método de Nijmegen Bethesda original. Foram avaliados 184 pacientes com hemofilia A entre novembro de 2012 e fevereiro de 2015. Resultados: Dos pacientes avaliados, 149 (80,98%) não revelaram presença do inibidor, enquanto em 35 (19,02%) essa presença foi detectada. Entre os portadores dos inibidores, a maioria dos pacientes hemofílicos apresentaram títulos elevados do inibidor (57,2%). Conclusão: A incidência elevada de inibidor do fator VIII na população em estudo pode ser explicada pelo tipo de tratamento utilizado no HEMOCE, o qual se baseia no fator VIII na sua forma recombinante. Os resultados devem ser avaliados com critério para que o tratamento e o acompanhamento desses pacientes sejam realizados da maneira mais segura possível.

Erythrocyte oxidative stress markers in children with sickle cell disease / Marcadores de estresse oxidativo em eritrócitos de crianças com doença falciforme

Abstract Objective To determine eight parameters of oxidative stress markers in erythrocytes from children with sickle cell disease and compare with the same parameters in erythrocytes from healthy children, since oxidative stress plays an important role in the pathophysiology of sickle cell disease and because this disease is a serious public health problem in many countries. Methods Blood samples were obtained from 45 children with sickle cell disease (21 males and 24 females with a mean age of 9 years; range: 3–13 years) and 280 blood samples were obtained from children without hemoglobinopathies (137 males and 143 females with a mean age of 10 years; range: 8–11 years), as a control group. All blood samples were analyzed for methemoglobin, reduced glutathione, thiobarbituric acid reactive substances, percentage of hemolysis, reactive oxygen species, and activity of the enzymes glucose 6-phosphate dehydrogenase, superoxide dismutase, and catalase. Data were analyzed using Student's t-test and were expressed as the mean ± standard deviation. A p-value of <0.05 was considered significant. Results Significant differences were observed between children with sickle cell disease and the control group for the parameters methemoglobin, thiobarbituric acid reactive substances, hemolysis, glucose 6-phosphate dehydrogenase activity, and reactive oxygen species, with higher levels in the patients than in the controls. Conclusions Oxidative stress parameters in children's erythrocytes were determined using simple laboratory methods with small volumes of blood; these biomarkers can be useful to evaluate disease progression and outcomes in patients.

Resumo Objetivo Determinar parâmetros de estresse oxidativo em eritrócitos de crianças com doença falciforme e compará-los com os mesmos parâmetros em eritrócitos de crianças saudáveis, pois o estresse oxidativo desempenha um importante papel na fisiopatologia da doença falciforme, considerada um sério problema de saúde pública em muitos países. Métodos Foram obtidas amostras de sangue de 45 crianças com doença falciforme (21 meninos e 24 meninas com média de 9 anos, variação de 3 a 13) e 280 amostras de sangue de crianças sem hemoglobinopatias (137 meninos e 143 meninas com média de 10 anos, variação de 8 a 11), como grupo controle. Em todas as amostras foram determinados meta-hemoglobina, glutationa reduzida, substâncias reativas ao ácido tiobarbitúrico, porcentagem de hemólise, espécies reativas de oxigênio e atividade das enzimas glucose6-fosfato desidrogenase, superóxido dismutase e catalase. Os dados foram analisados com o teste t de Student e foram expressos como média ± desvio padrão. Um valor de p < 0,05 foi considerado significativo. Resultados Foram observadas diferenças significativas entre as crianças com doença falciforme e o grupo controle para os parâmetros meta-hemoglobina, substâncias reativas ao ácido tiobarbitúrico, porcentagem de hemólise, espécies reativas de oxigênio e atividade da enzima glucose6-fosfato desidrogenase, com níveis aumentados nos pacientes. Conclusões Foi possível determinar parâmetros de estresse oxidativo em eritrócitos de crianças, com técnicas laboratoriais simples e pequenos volumes de sangue. Esses biomarcadores podem ser úteis na avaliação da progressão e dos resultados de tratamentos da doença.

Von Willebrand Disease Lab Diagnosis.

The hemorrhagic diseases are characterized by bleeding which can vary considerably according to their severity. The von Willebrand disease (VWD) is the most frequent hereditary hemorrhagic disease and the prevalence of clinically significant disease is probably closer to 1:1000, being an extremely heterogeneous and complex disorder that is related to the deficiency in concentration, structure or function of von Willebrand factor (VWF). The VWD is divided into type 1, with partial deficiency of the VWF, type 2, with qualitative defects in the molecule with four subdivisions, and type 3, with very low or undetectable levels of plasma and platelet VWF and ristocetin cofactor activity. The laboratory diagnosis of VWD is complex. Specific tests that assess the functionality and concentrations of the VWF and FVIII are needed. The routine tests are the bleeding time, the activated partial thromboplastin time and the platelet count, however, singly, they may not suggest the diagnosis of VWD, requiring further specific tests, such as VWF function evaluation through its ristocetin cofactor assay (VWF:RCo), VWF protein concentration immunoassay (VWF:Ag), the factor VIII coagulation assay ( FVIII: C), VWF binding to immobilized collagen (VWF:CB), ristocetin-induced platelet aggregation (RIPA), VWF multimers patterns, factor VIII binding of immobilized VWF (VWF:FVIIIB), among others. From the moment the diagnosis is confirmed, the appropriate treatment for each patient is sought, with the purpose of increasing plasma concentrations of the deficient protein, both in bleeding episodes, as for invasive procedures. Although diagnosis facilitates treatment other approach in the present scenario is prenatal diagnosis which, is the need of the hour.

Erythrocyte oxidative stress markers in children with sickle cell disease.

OBJECTIVE: To determine eight parameters of oxidative stress markers in erythrocytes from children with sickle cell disease and compare with the same parameters in erythrocytes from healthy children, since oxidative stress plays an important role in the pathophysiology of sickle cell disease and because this disease is a serious public health problem in many countries. METHODS: Blood samples were obtained from 45 children with sickle cell disease (21 males and 24 females with a mean age of 9 years; range: 3-13 years) and 280 blood samples were obtained from children without hemoglobinopathies (137 males and 143 females with a mean age of 10 years; range: 8-11 years), as a control group. All blood samples were analyzed for methemoglobin, reduced glutathione, thiobarbituric acid reactive substances, percentage of hemolysis, reactive oxygen species, and activity of the enzymes glucose 6-phosphate dehydrogenase, superoxide dismutase, and catalase. Data were analyzed using Student's t-test and were expressed as the mean±standard deviation. A p-value of <0.05 was considered significant. RESULTS: Significant differences were observed between children with sickle cell disease and the control group for the parameters methemoglobin, thiobarbituric acid reactive substances, hemolysis, glucose 6-phosphate dehydrogenase activity, and reactive oxygen species, with higher levels in the patients than in the controls. CONCLUSIONS: Oxidative stress parameters in children's erythrocytes were determined using simple laboratory methods with small volumes of blood; these biomarkers can be useful to evaluate disease progression and outcomes in patients.

The FXR agonist 6ECDCA reduces hepatic steatosis and oxidative stress induced by ethanol and low-protein diet in mice.

BACKGROUND AND AIM: Excessive ethanol consumption can lead to development of hepatic steatosis. Since the FXR receptor regulates adipose cell function and liver lipid metabolism, the aim of this work was to examine the effects of the FXR agonist 6ECDCA on alcoholic liver steatosis development and on oxidative stress induced by ethanol consumption. METHODS: Swiss mice (n=24) received a low-protein diet (6%) and a liquid diet containing 10% ethanol or water for 6weeks. In the last 15days mice received oral treatment with 6ECDCA (3mgkg(-1)) or 1% tween (vehicle). The experimental groups (n=6) were: water+tween, water+6ECDCA, ethanol+tween and ethanol+6ECDCA. Moreover, as a diet control, we used a basal group (n=6), fed by a normal-proteic diet (23%) and water. After the treatment period, the animals were anesthetized for sample collection to perform plasma biochemistry assays, hepatic oxidative stress assays, hepatic cholesterol and triglycerides measurements, liver histology and hepatic gene expression. RESULTS: Ethanol associated with low-protein diet induced hepatic oxidative stress, increased plasma transaminases and induced hepatic lipid accumulation. Many of these parameters were reversed by the administration of 6ECDCA, including amelioration of lipid accumulation and lipoperoxidation, and reduction of reactive oxygen species. These effects were possibly mediated by regulation of Srebpf1 and FAS gene expression, both reduced by the FXR agonist. CONCLUSIONS: Our data demonstrated that 6ECDCA reverses the accumulation of lipids in the liver and decreases the oxidative stress induced by ethanol and low-protein diet. This FXR agonist is promising as a potential therapy for alcoholic liver steatosis.

Protective effect of flavonoids against reactive oxygen species production in sickle cell anemia patients treated with hydroxyurea.

OBJECTIVE: The aim of this study was to evaluate the protective effects of quercetin, rutin, hesperidin and myricetin against reactive oxygen species production with the oxidizing action of tert-butylhydroperoxide in erythrocytes from normal subjects and sickle cell anemia carriers treated with hydroxyurea. METHODS: Detection of intracellular reactive oxygen species was carried out using a liposoluble probe, 2',7'-dichlorfluorescein-diacetate (DCFH-DA). A 10% erythrocyte suspension was incubated with flavonoids (quercetin, rutin, hesperidin or myricetin; 30, 50, and 100 µmol/L), and then incubated with tert-butylhydroperoxide (75 µmol/L). Untreated samples were used as controls. RESULTS: Red blood cell exposure to tert-butylhydroperoxide resulted in significant increases in the generation of intracellular reactive oxygen species compared to basal levels. Reactive oxygen species production was significantly inhibited when red blood cells were pre-incubated with flavonoids, both in normal individuals and in patients with sickle cell anemia. Quercetin and rutin had the highest antioxidant activity, followed by myricetin and hesperidin. CONCLUSION: Flavonoids, in particular quercetin and rutin, showed better antioxidant effects against damage caused by excess reactive oxygen species characteristic of sickle cell anemia. Results obtained with patients under treatment with hydroxyurea suggest an additional protective effect when associated with the use of flavonoids.

Protective effect of flavonoids against reactive oxygen species production in sickle cell anemia patients treated with hydroxyurea

OBJECTIVE: The aim of this study was to evaluate the protective effects of quercetin, rutin, hesperidin and myricetin against reactive oxygen species production with the oxidizing action of tert-butylhydroperoxide in erythrocytes from normal subjects and sickle cell anemia carriers treated with hydroxyurea. METHODS: Detection of intracellular reactive oxygen species was carried out using a liposoluble probe, 2',7'-dichlorfluorescein-diacetate (DCFH-DA). A 10% erythrocyte suspension was incubated with flavonoids (quercetin, rutin, hesperidin or myricetin; 30, 50, and 100 µmol/L), and then incubated withtert-butylhydroperoxide (75 µmol/L). Untreated samples were used as controls. RESULTS: Red blood cell exposure to tert-butylhydroperoxide resulted in significant increases in the generation of intracellular reactive oxygen species compared to basal levels. Reactive oxygen species production was significantly inhibited when red blood cells were pre-incubated with flavonoids, both in normal individuals and in patients with sickle cell anemia. Quercetin and rutin had the highest antioxidant activity, followed by myricetin and hesperidin. CONCLUSION: Flavonoids, in particular quercetin and rutin, showed better antioxidant effects against damage caused by excess reactive oxygen species characteristic of sickle cell anemia. Results obtained with patients under treatment with hydroxyurea suggest an additional protective effect when associated with the use of flavonoids.

Reference values for methemoglobin concentrations in children.

OBJECTIVE: The aim of this work was to establish reference values for methemoglobin levels in 6 to 10-year-old children. METHODS: Methemoglobin concentrations were studied in clinically healthy children. The method for methemoglobin measurement used, neither uses highly toxic chemical compounds nor expensive enzymatic methods, thus it is feasible in the laboratory routine. RESULTS: The results showed higher reference values for clinically healthy children (from 3.61 to 6.44%) than for adults (from 1.9 to 3.8%). CONCLUSION: The higher concentrations of methemoglobin in children may be explained by smaller amounts of soluble cofactor cytochrome b5 and reduced activity of the cytochrome b5 reductase enzyme in red blood cells which make children particularly susceptible to the development of methemoglobinemia. Methemoglobin concentrations in children are higher than in normal adult subjects thus, adult reference values cannot be used to interpret infant methemoglobinemia.

O uso do pool de plasma caseiro interfere no valor da RNI? / Does the use of in-house pooled plasma interfere in the INR value?

INTRODUÇÃO: O tempo de protrombina (TP) é o teste de escolha para monitorar o nível de anticoagulação em pacientes que fazem uso de anticoagulantes orais. Nestes, atualmente, a anticoagulação é monitorada pelo valor da relação normatizada internacional (RNI). OBJETIVO: A finalidade deste trabalho foi determinar se um pool de plasma caseiro, com cinco (P5) e 20 (P20) amostras, pode ser usado como controle normal do TP e se o uso deste pool interfere no resultado da RNI. MATERIAL E MÉTODOS: Foram 32 dias de experimentos. Os dois pools de plasma caseiro foram analisados em relação a um controle normal de plasma comercial (PC). Para cada dia de experimento, fez-se o TP de P5, P20 e PC e também se determinou o valor de RNI para P5, P20 e PC em pacientes que fazem uso de anticoagulante oral. As ferramentas estatísticas utilizadas foram média (X), análise de variância e teste de Tukey. RESULTADOS: A análise estatística demonstrou que os valores do TP e da RNI não são significativamente diferentes para PC, P5 e P20. CONCLUSÃO: O pool de plasma caseiro pode ser utilizado como controle normal do TP e o seu uso não interfere no valor da RNI.

INTRODUCTION: The prothrombin time (PT) test is commonly used to monitor anticoagulant levels in patients undergoing oral anticoagulant therapy. Currently, anticoagulation levels have been assessed through the international normalized ratio (INR) value. OBJECTIVE: The objective of this study was to determine if in-house preparations of polled plasma, containing five (P5) and 20 (P20) samples, respectively, may be used as normal control of PT and to assess its interference in INR values. MATERIAL AND METHODS: The experiment was performed in 32 days. Both polled plasma preparations were analyzed in comparison with a commercial control (PC). PT was performed for PC, P5 and P20 daily and the INR value for PC, P5 and P20 was assessed in patients undergoing oral anticoagulant therapy. The applied statistical tools were mean value (X), analysis of variance and Tukey test. RESULTS: There were no statiscally significant differences in PT and INR for PC, P5 and P20. CONCLUSION: In-house polled plasma (P5 and P20) may be applied as normal control of PT and it does not interfere in the INR value.

Reference values for methemoglobin concentrations in children

OBJECTIVE: The aim of this work was to establish reference values for methemoglobin levels in 6 to 10-year-old children. METHODS: Methemoglobin concentrations were studied in clinically healthy children. The method for methemoglobin measurement used, neither uses highly toxic chemical compounds nor expensive enzymatic methods, thus it is feasible in the laboratory routine. RESULTS: The results showed higher reference values for clinically healthy children (from 3.61 to 6.44 percent) than for adults (from 1.9 to 3.8 percent). CONCLUSIONS: The higher concentrations of methemoglobin in children may be explained by smaller amounts of soluble cofactor cytochrome b5 and reduced activity of the cytochrome b5 reductase enzyme in red blood cells which make children particularly susceptible to the development of methemoglobinemia. Methemoglobin concentrations in children are higher than in normal adult subjects thus, adult reference values cannot be used to interpret infant methemoglobinemia.