Salivary nitrite and systemic biomarkers in obese individuals with periodontitis submitted to FMD

Abstract The objective of this 9-month clinical study is to assess the impact of one-stage full-mouth disinfection (FMD) on salivary nitrite levels and systemic biomarkers and its correlation with total subgingival bacterial load in obese and non-obese patients with periodontitis. In total, 94 patients (55 obese and 39 non-obese) were initially evaluated, seven were lost during follow-up, resulting in 87 individuals at the end of the study. Outcomes were assessed at baseline, 3, 6, and 9 months post periodontal treatment by FMD. Salivary nitrite levels were determined using Griess reagent. Blood samples were collected to determine C-Reactive Protein (CRP), alkaline phosphatase and fasting blood glucose. Real-time PCR was used to determine the total subgingival bacterial load. FMD protocol resulted in increased salivary nitrite levels at 6- and 9-months post-treatment in the non-obese group (p<0.05). In obese individuals, FMD treatment led to an increase in salivary nitrite levels at 6 months (p<0.05); however, at 9 months, the nitrite levels returned to baseline levels. For both groups, the highest nitrite values were observed at 6 months. In addition, in both groups, FMD was associated with a decrease in biomarkers related to systemic inflammation and cardiovascular diseases, such as CRP (p<0.05) and alkaline phosphatase (p<0.05), and had no impact on the fasting blood glucose. This study demonstrates that obese patients with periodontitis present similar salivary nitrite levels when compared with non-obese individuals. FMD protocol resulted in increases in salivary nitrite levels and was associated with a positive impact on systemic biomarkers, regardless of obesity status.

Resumo O objetivo deste estudo clínico, é avaliar o impacto da desinfecção bucal completa (DBC) nos níveis de nitrito salivar e biomarcadores sistêmicos e sua correlação com a carga bacteriana subgengival total em pacientes obesos e não obesos com periodontite. No total, 94 pacientes (55 obesos e 39 não obesos) foram avaliados inicialmente, sete foram perdidos durante o estudo, resultando em 87 indivíduos ao final. Os resultados foram avaliados no início do estudo, 3, 6 e 9 meses após o tratamento periodontal por DBC. Os níveis de nitrito salivar foram determinados usando o reagente de Griess. Amostras de sangue foram coletadas para determinação da Proteína C Reativa (PCR), fosfatase alcalina e glicemia de jejum. A PCR em tempo real foi usada para determinar a carga bacteriana subgengival total. O protocolo de DBC resultou em níveis aumentados de nitrito salivar em 6 e 9 meses após o tratamento no grupo de não obesos (p <0,05). Em indivíduos obesos, o tratamento da DBC levou a um aumento nos níveis de nitrito salivar em 6 meses (p <0,05); no entanto, aos 9 meses, os níveis de nitrito voltaram aos níveis basais. Para ambos os grupos, os maiores valores de nitrito foram observados aos 6 meses. Além disso, em ambos os grupos, a DBC foi associada à diminuição dos biomarcadores relacionados à inflamação sistêmica e doenças cardiovasculares, como PCR (p <0,05) e fosfatase alcalina (p <0,05), e não teve impacto na glicemia de jejum. Este estudo demonstra que pacientes obesos com periodontite apresentam níveis de nitrito salivar semelhantes quando comparados a indivíduos não obesos. O protocolo de DBC resultou em aumentos nos níveis de nitrito salivar e foi associado a um impacto positivo nos biomarcadores sistêmicos, independentemente do status de obesidade.

Role of urinary nitrites in predicting steroid responsiveness of nephrotic syndrome: a study conducted in tertiary care center

Background: Nephrotic Syndrome (NS) is a common chronic disorder, characterized by alterations of selective permeability at the glomerular capillary wall, resulting in its inability to restrict the urinary loss of protein. Urinary nitrite excretion serves as a useful investigation in differentiating between steroid responsive and steroid resistant nephrotic syndrome. The aim of the study was to assess the relation between urinary nitrite levels and steroid responsiveness in nephrotic syndrome in children.Methods: 76 children were enrolled in the study suffering with nephrotic syndrome of which 58 children were Steroid Sensitive (SSNS) and 18 were Steroid Resistant (SRNS). 25 children were enrolled as controls. The urinary nitrites were estimated in these subjects and the results were analyzed.Results: All the control subjects were tested negative for urinary nitrites. After achieving remission with steroids, out of 58 SSNS subjects' 27 subjects tested positive for urinary nitrites, remaining 31 tested negatives for the same. Of the 18 SRNS subjects 1 subject tested positive for urinary nitrites remaining 17 subjects were tested negative for the same.Conclusions: The findings of present study suggest that urinary nitrite excretion is increased in patients with steroid responsive nephrotic syndrome. The urinary nitrite estimation has low NPV and high PPV in predicting steroid responsiveness.

Omeprazole and adenocarcinoma in the stomach of rats submitted to duodenogastric reflux. Is there a protective effect?

Abstract Purpose: To investigate the role of omeprazole and nitrites on the gastric mucosa of rats submitted to specific techniques to induce duodenogastric reflux. Methods: One hundred and twenty Wistar rats were divided into three groups: Group I (n=40) -gastrotomy; Group II (n=40) - duodenogastric reflux after gastrojejunoanastomosis latero-lateral (DGR); Group III (n=40) - retrograde duodenogastric reflux through the pylorus (DGR-P). The groups were divided into 4 subgroups of 10 animals, respectively treated for 16 weeks with water, omeprazole 1.6 mg / rat / day, nitrite 600 mg / kg / day and omeprazole plus nitrite simultaneously. Results: The proliferative lesions found were: squamous hyperplasia - 69.1%, adenomatous hyperplasia in the anastomosis - 29.1% and prepyloric adenomatous hyperplasia - 42.5%. Adenocarcinomas were registered in 7 animals (5.8%): one in Group I (omeprazole plus nitrite), two in Group II (omeprazole and nitrite plus omeprazole) and four in Group III (water, nitrite, omeprazole and omeprazole plus nitrite). Conclusions: The occurrence of squamous hyperplasia, adenomatous hyperplasia and adenocarcinoma increased after gastrojejunal anastomoses, which cause duodenogastric reflux. The association of omeprazole did not protect the development of proliferative lesions and cancer induced by duodenogastric reflux in rats.

Marcadores de estrés oxidativo en pacientes con esclerosis múltiple durante un brote y su remisión / Oxidative stress markers in patients with multiple sclerosis during an outbreak and its remission / Marcadores de estresse oxidativo em pacientes com esclerose múltipla durante um surto e sua remissão

La esclerosis múltiple remitente-recurrente (EM-RR) es una enfermedad desmielinizante del sistema nervioso central. A fin de entender la asociación del estrés oxidativo a nivel periférico con la recaída de la enfermedad se determinaron los niveles de marcadores de estrés oxidativo en plasma de pacientes en la recaída o brote y una semana después de la misma. Se analizaron muestras de 60 personas (20 pacientes con recaída, 20 pacientes sin recaída y 20 controles sanos). Se cuantificaron mediante métodos espectrofotométricos las actividades enzimáticas de óxido nítrico sintasa (ONS), glutatión peroxidasa (GPx), los niveles de lipoperóxidos y nitritos-nitratos y la fluidez de membrana. En el brote de la enfermedad aumentan significativamente los niveles de las actividades enzimáticas de ONS y GPx y los niveles de nitritos-nitratos y lipoperóxidos (p<0,01 en todos los casos), al ser comparados con los de individuos sanos. Dichos parámetros disminuyeron significativamente una semana después de iniciado el brote. Además, los parámetros evaluados se mantuvieron elevados en pacientes que no experimentaron un brote de la enfermedad cuando se los comparó con individuos sanos. La fluidez de membrana en los pacientes con y sin brote fue similar a la de los controles. En conclusión, el estrés oxidativo es un componente importante en los pacientes con esclerosis múltiple.

Recurrent-remitting multiple sclerosis (RR-MS) is a demyelinating disease of the central nervous system. In order to understand the association of oxidative stress at the peripheral level with the relapse of the disease, the levels of oxidative stress markers in plasma of patients in the relapse or outbreak and one week after relapse were determined. Samples of 60 subjects were analyzed (20 patients in relapse, 20 patients without relapse, and 20 healthy controls). The enzymatic activities of nitric oxide synthase (NOS), glutathione peroxidase (GPx), lipoperoxides and nitrite-nitrate levels and membrane fluidity were quantified by spectrophotometric methods. In relapse, the levels of enzymatic activities of NOS and GPx, and the levels of lipoperoxides and nitrites-nitrates were significantly increased (p<0.01, in all cases), compared with healthy individuals. These parameters decreased significantly 1 week after the start of the outbreak. In addition, the parameters evaluated remained high in patients who did not experience an outbreak of the disease compared to healthy subjects. The membrane fluidity in the patients with and without outbreak was similar to that of the controls. In conclusion, oxidative stress is an important component in patients with multiple sclerosis.

A esclerose múltipla recorrente-remitente (EM-RR) é uma doença desmielinizante do sistema nervoso central. Para compreender a associação do estresse oxidativo a nível periférico com a recaída da doença foram determinados os níveis de marcadores de estresse oxidativo em plasma de doentes na recaída ou surto e uma semana após a recaída. Foram analisadas a amostras de 60 pessoas (20 pacientes com recaída, 20 pacientes sem recaída e 20 controles saudáveis). As atividades enzimáticas de óxido nítrico sintase (ONS), glutationa peroxidase (GPX), os níveis de lipoperóxidos e nitritos-nitratos e a fluidez de membrana foram quantificadas por métodos espectrofotométricos. No surto da doença aumentam em forma significativa os níveis da atividade enzimática de ONS e GPX, e os níveis de nitritos-nitratos e lipoperóxidos (p<0,01 em todos os casos), em comparação com os indivíduos saudáveis. Esses parâmetros diminuíram significativamente uma semana após o início do surto. Além disso, os parâmetros avaliados permaneceram elevados em pacientes que não experimentaram um surto da doença quando comparados com indivíduos saudáveis. A fluência de membrana nos pacientes com e sem surto foi semelhante à dos controles. Em conclusão, o estresse oxidativo é um componente importante nos pacientes com esclerose múltipla.

Metahemoglobinemia relacionada con ingesta de puré de acelgas / Methemoglobinemia due to ingestion of chard puree

La metahemoglobinemia es un síndrome clínico dado por la presencia de una forma aberrante de hemoglobina, ocasionada por diversos agentes oxidantes. Se describe un caso clínico de metahemoglobinemia severa asociada a la ingesta de puré de acelgas con alto contenido en nitratos y nitritos. Paciente de un año, con antecedentes de comunicación interauricular (CIA), que presentó un cambio en coloración de la piel 7 h antes, en forma progresiva, acompañado de vómitos. Ingresó al Departamento de Emergencia con cianosis generalizada que no mejoró con oxigenoterapia, taquicardia y tendencia a hipotensión arterial. En cuidados intensivos se realizó ecocardiograma que evidenció CIA sin repercusión hemodinámica. Metahemoglobinemia 37%. Se realizó dosis de azul de metileno al 1% por vía intravenosa, con franca mejoría clínica a la hora de la administración del antídoto y descenso de niveles de metahemoglobina. Alta médica a las 36 horas del ingreso. Existía una relación cronológica entre la exposición a nitratos por ingesta de un puré de acelgas y la aparición del cuadro. Los niveles de nitratos hallados en dicho alimento fueron muy elevados considerando estándares internacionales, lo que sumado a una inadecuada conservación del alimento cocido los días previos, permitió confirmar el planteo etiológico realizado. Resulta importante sospechar esta entidad patológica poco frecuente frente a cianosis que no mejora con oxígeno, y prevenir cuadros similares al descrito mediante una adecuada manipulación y conservación de las verduras con alto contenido en nitratos.

Methemoglobinemia is a clinical syndrome due to the presence of an aberrant form of hemoglobin, caused by various oxidizing agents. The study reports a case of severe methemoglobinemia associated with the ingestion of chard puree with high levels of nitrates and nitrites. A 1-year-old patient with a history of atrial septal defect (ASD), who progressively showed change of skin color 7 hours earlier, accompanied by vomiting. She was admitted to the Emergency Department with generalized cyanosis not improving with oxygen therapy, tachycardia and tendency to hypotension. In the intensive care unit, an echocardiogram showed ASD without hemodynamic complications. Methemoglobinemia 37%. A 1% methylene blue dose was administered intravenously, with clinical improvement one hour after antidote administration and decrease in methemoglobin levels. Medical discharge at 36 hours of admission. There was a chronological relationship between nitrates exposure by ingestion of chard puree and the clinical onset of methemoglobinemia. The toxic cause was confirmed after high nitrates levels were found in this vegetable considering international standards, and an inadequate preservation of the cooked chard on previous days. It is important to suspect this rare pathological entity when cyanosis fails to improve with oxygen, and to prevent poisonings similar to those described by an adequate manipulation and preservation of vegetables with high nitrate levels.

Performance of the dipstick screening test as a predictor of negative urine culture / Desempenho da fita de urina como resultado presuntivo para cultura de urina negativa

ABSTRACT Objective To investigate whether the urine dipstick screening test can be used to predict urine culture results. Methods A retrospective study conducted between January and December 2014 based on data from 8,587 patients with a medical order for urine dipstick test, urine sediment analysis and urine culture. Sensitivity, specificity, positive and negative predictive values were determined and ROC curve analysis was performed. Results The percentage of positive cultures was 17.5%. Nitrite had 28% sensitivity and 99% specificity, with positive and negative predictive values of 89% and 87%, respectively. Leukocyte esterase had 79% sensitivity and 84% specificity, with positive and negative predictive values of 51% and 95%, respectively. The combination of positive nitrite or positive leukocyte esterase tests had 85% sensitivity and 84% specificity, with positive and negative predictive values of 53% and 96%, respectively. Positive urinary sediment (more than ten leukocytes per microliter) had 92% sensitivity and 71% specificity, with positive and negative predictive values of 40% and 98%, respectively. The combination of nitrite positive test and positive urinary sediment had 82% sensitivity and 99% specificity, with positive and negative predictive values of 91% and 98%, respectively. The combination of nitrite or leukocyte esterase positive tests and positive urinary sediment had the highest sensitivity (94%) and specificity (84%), with positive and negative predictive values of 58% and 99%, respectively. Based on ROC curve analysis, the best indicator of positive urine culture was the combination of positives leukocyte esterase or nitrite tests and positive urinary sediment, followed by positives leukocyte and nitrite tests, positive urinary sediment alone, positive leukocyte esterase test alone, positive nitrite test alone and finally association of positives nitrite and urinary sediment (AUC: 0.845, 0.844, 0.817, 0.814, 0.635 and 0.626, respectively). Conclusion A negative urine culture can be predicted by negative dipstick test results. Therefore, this test may be a reliable predictor of negative urine culture.

RESUMO Objetivo Verificar se a triagem de urina por fitas reativas é capaz de predizer a cultura de urina. Métodos Estudo retrospectivo realizado entre janeiro e dezembro de 2014 com 8.587 pacientes, com solicitação médica de triagem de urina (fita), sedimento urinário e cultura de urina. Foram analisados sensibilidade, especificidade, valor preditivo positivo, valor preditivo negativo e curva ROC. Resultados Foram positivas 17,5% das culturas. O nitrito apresentou sensibilidade de 28% e especificidade de 99%. O valor preditivo positivo foi de 89% e o valor preditivo negativo de 87%. Esterase apresentou sensibilidade de 79% e especificidade de 84%. Valor preditivo positivo e valor preditivo negativo foram de 51% e 95%, respectivamente. A combinação de nitrito ou esterase positivos apresentou sensibilidade de 85% e especificidade de 84%. Valor preditivo positivo e valor preditivo negativo foram, respectivamente, 53% e 96%. O sedimento positivo (mais de dez leucócitos por microlitro) apresentou sensibilidade de 92% e especificidade de 71%. O valor preditivo positivo foi 40% e o negativo, 98%. A combinação de nitrito e sedimento urinário positivos apresentou sensibilidade de 82% e especificidade de 99%. Os valores preditivos positivo e negativo foram 91% e 98%, respectivamente. Para o nitrito ou esterase positivos mais os leucócitos positivos, a sensibilidade foi de 94% e a especificidade de 84%. O valor preditivo positivo foi de 58% e o negativo foi de 99%. Com base na curva ROC, o melhor indicador de urocultura positiva foi a associação entre a esterase ou nitrito positivos na fita mais os leucócitos positivos no sedimento, seguido por nitrito e esterase positivos, sedimento urinário positivo isolado, esterase positiva isolada, nitrito positivo isolado e, finalmente, pela associação entre nitrito e sedimento urinário positivos (AUC: 0,845, 0,844, 0,817, 0,814, 0,635 e 0,626, respectivamente). Conclusão Uma urocultura negativa pode ser prevista com resultados negativos na fita. Portanto, este teste pode ser um preditor confiável de urocultura negativa.

Effects of Nitrate Intake on Myocardial Ischemia-Reperfusion Injury in Diabetic Rats / Efeitos do Consumo de Nitrato na Lesão de Isquemia-Reperfusão Miocárdica em Ratos Diabéticos

Abstract Background: Coronary artery disease is 2-3 times more common in diabetic individuals. Dietary nitrate/nitrite has beneficial effects in both diabetes and cardiovascular disease. It also has protective effects against myocardial ischemia-reperfusion (IR) injury in healthy animals. However, the effects of nitrate on myocardial IR injury in diabetic rats have not yet been investigated. Objective: We examined the effects of dietary nitrate on myocardial IR injury in streptozotocin-nicotinamide-induced diabetic rats. Method: Rats were divided into four groups (n=7 in each group): control, control+nitrate, diabetes, and diabetes+nitrate. Type 2 diabetes was induced by injection of streptozotocin and nicotinamide. Nitrate (sodium nitrate) was added to drinking water (100 mg/L) for 2 months. The hearts were perfused in a Langendorff apparatus at 2 months and assessed before (baseline) and after myocardial IR for the following parameters: left ventricular developed pressure (LVDP), minimum and maximum rates of pressure change in the left ventricle (±dP/dt), endothelial nitric oxide (NO) synthase (eNOS) and inducible NO synthase (iNOS) mRNA expression, and levels of malondialdehyde (MDA) and NO metabolites (NOx). Results: Recovery of LVDP and ±dP/dt was lower in diabetic rats versus controls, but almost normalized after nitrate intake. Diabetic rats had lower eNOS and higher iNOS expression both at baseline and after IR, and dietary nitrate restored these parameters to normal values after IR. Compared with controls, heart NOx level was lower in diabetic rats at baseline but was higher after IR. Diabetic rats had higher MDA levels both at baseline and after IR, which along with heart NOx levels decreased following nitrate intake. Conclusion: Dietary nitrate in diabetic rats provides cardioprotection against IR injury by regulating eNOS and iNOS expression and inhibiting lipid peroxidation in the heart.

Resumo Fundamentos: A doença arterial coronariana é duas a três vezes mais comum em indivíduos diabéticos. O nitrato/nitrito dietético tem efeitos benéficos tanto para o diabetes quanto para a doença cardiovascular, assim como efeitos protetores contra a lesão de isquemia-reperfusão (IR) miocárdica em animais saudáveis. Porém, os efeitos do nitrato na lesão de IR miocárdica em ratos diabéticos ainda não foram investigados. Objetivos: Foram examinados os efeitos sobre a lesão de IR miocárdica da adição de nitrato à dieta de ratos com diabetes mellitus tipo 2 induzido por estreptozotocina-nicotinamida. Métodos: Os ratos foram divididos em quatro grupos (n = 7 em cada grupo): controle, controle+nitrato, diabetes e diabetes+nitrato. O diabetes foi induzido nos animais por injeção de estreptozotocina e nicotinamida. Nitrato (nitrato de sódio) foi adicionado à água de beber (100 mg/L) por 2 meses. Os corações foram perfundidos em sistema de Langendorff aos 2 meses e avaliados antes (basal) e após IR miocárdica em relação aos seguintes parâmetros: pressão desenvolvida no ventrículo esquerdo (PDVE), taxas máximas de variação positiva e negativa da pressão ventricular esquerda (±dP/dt), expressão do RNAm da óxido nítrico (NO) sintase (NOS) endotelial (eNOS) e da NOS induzível (iNOS), além de níveis de malondialdeído (MDA) e metabólitos do óxido nítrico (NOx). Resultados: A recuperação da PDVE e ±dP/dt foi inferior nos ratos diabéticos versus controles, mas quase normalizou após ingestão de nitrato. Ratos diabéticos apresentaram expressão diminuída de eNOS e aumentada de iNOS tanto no estado basal quanto após IR, e o consumo dietético de nitrato restaurou estes valores para o estado normal após a IR. O nível de NOx cardíaco foi menor nos ratos diabéticos em comparação aos controles no momento basal, mas foi superior após a IR. Ratos diabéticos apresentaram níveis mais elevados de MDA tanto no estado basal quanto após IR que, juntamente com os níveis cardíacos de NOx, reduziram após consumo dietético do nitrato. Conclusões: O consumo dietético de nitrato por ratos diabéticos ofereceu cardioproteção contra a lesão de IR através da regulação da expressão de eNOS e iNOS e inibição da peroxidação lipídica no coração.

Asymptomatic Bacteriuriain Pregnant Women: Screening Bya Simple Method and Treatment with Single Dose Antimicrobial Therapy

The term asymptomatic bacteriuria in pregnancy indicates persistent actively multiplying bacteria within the urinary tract without showing any symptom in pregnancy. A total of 500 pregnant women were screened for the incidence of asymptomatic bacteriuria by comparing the reliability of urine dip stick evaluation for nitrites and leukocyte esterase activity with that of urine culture in diagnosing asymptomaticbacteriuria. The efficacy of single dose antimicrobial therapy (2 g of Cephalexin or 3 g of Amoxycillin) was evaluated for eradicating asymptomatic bacteriuria. The incidence was found to be 9.2% among the 500 cases in the study group. The dip stick screening could detect the bacteriuric patients correctly in 89.1% of cases. Single dose therapy cured 76.1% of asymptomatic bacteriuria patients. Amoxycillin was found to be more effective when compared to Cephalexin as a single dose antimicrobial therapy.

Asociación entre niveles de proteína C-reactiva y óxido nítrico con el pronóstico de pacientes con infarto cerebral agudo / Association of C-reactive protein and nitric oxide levels with the prognosis of acute ischemic stroke

Introducción: La inflamación y alteraciones en la biodisponibilidad del óxido nítrico (NO) han sido involucradas en la fisiopatología de la enfermedad cerebrovascular. Objetivo: El objetivo del estudio fue determinar el valor pronóstico de la medición de metabolitos del NO y marcadores inflamatorios en pacientes con infarto cerebral agudo. Materiales y métodos: Se incluyeron 158 pacientes con diagnóstico de infarto cerebral agudo en un estudio observacional de cohorte. Entre 48 y 72 horas del inicio de los síntomas se tomó una muestra de sangre para determinación del perfil bioquímico, marcadores inflamatorios (PCR, IL1-β, IL6, TNF-α) y nitritos/nitratos plasmáticos. Se realizó seguimiento durante 2 años para determinar la aparición de un nuevo evento (infarto cerebral, infarto de miocardio, falla cardiaca) o muerte de origen vascular. Un análisis de regresión multivariada de Cox permitió determinar los factores asociados independientemente con el desenlace. Resultados: La edad promedio fue 70,5 ± 12,8 años. El 39,2% de los sujetos incluidos presentó el desenlace durante los primeros 24 meses de seguimiento. Los niveles de PCR > 12 mg/L (HR 2,22, IC 95% 1,07-4,59) y el puntaje > 13 en la escala NIHSS al ingreso (HR 2,81 IC 95% 1,46-5,41) se encontraron significativamente asociados con mayor riesgo de presentar un nuevo evento. La combinación de niveles de PCR < 12 mg/L y nitritos/nitratos < 35,5 µmol/L se identificó como un factor protector (HR 0,21, IC 95% 0,06-0,71). Conclusión: Este estudio sugiere que la determinación de nitritos/nitratos en conjunto con los niveles de PCR puede ser de utilidad para estratificar el riesgo de nuevos eventos en pacientes con infarto cerebral agudo.

Introduction: Inflammation and alterations in the bioavailability of nitric oxide (NO) have been involved in the pathophysiology of cerebrovascular disease. Objective: The aim of the study was to determine the prognostic value of measuring NO metabolites and inflammatory markers in patients with acute ischemic stroke. Materials and methods: A total of 158 patients with acute ischemic stroke were included in an observational cohort study. Between 48 and 72 hours post admission, a fasting blood sample was taken to determine the biochemical profile, inflammatory markers (CRP, IL1-β, IL6, TNF-α) and nitrites/nitrates plasma levels. The cohort's follow-up was conducted for two years to determine the occurrence of a new event (stroke, myocardial infarction, heart failure) or death of vascular origin. Comparisons between groups were made using the log-rank test. A Cox multivariate regression analysis permitted to determine factors independently associated with the outcome. Result: The mean age was 70.5 ± 12.8 years. 39.2% of the subjects presented the outcome during the first 24 months of follow-up. CRP levels > 12 mg/L (HR 2.22, 95% CI 1.07-4.59) and a score > 13 on the NIHSS scale at admission (HR 2.81 95% CI 1.46-5.41) were significantly associated with an increased risk of a new event. The combination of CRP levels < 12 mg/L and nitrites/nitrates levels < 35.5 mmol/L was identified as a protective factor (HR 0.21, 95% CI 0.06-0.71). Conclusion: This study demonstrates that the determination of CRP and NOx levels could be beneficial in clinical practice to stratify the risk of future events or death of vascular origin in acute ischemic stroke patients.

Levels of nitrates in a urea fertilized Kikuyu (Cenchrus clandestinus (Hochst. ex Chiov.) Morrone) pasture on the high plains of Antioquia, Colombia / Niveles de nitrato en pasto Kikuyo (Cenchrus clandestinus (Hochst. ex Chiov.) Morrone) fertilizado con urea en el antiplano de Antioquia, Colombia / Niveles de nitrato en pasto Kikuyo (Cenchrus clandestinus (Hochst. ex Chiov.) Morrone) fertilizado con urea en el antiplano de Antioquia, Colombia

Abstract Fertilization is one of the factors that can contribute to build-up of nitrates in kikuyu (Cenchrus clandestinus) pastures of the tropics. Field studies to evaluate the influence of nitrogen fertilization on yield and nitrate concentrations were conducted between December 2012 and June 2013 at the Agricultural Station of the National University at Santa Elena (Antioquia). The experimental design was a 4 x 4 block design with four replications in a monoculture paddock of kikuyu grass. Treatments were four levels of nitrogen applied as topdressing urea granules (0, 50, 100 and 200 kg/ha per plot). Whole grass samples (blades and stems) were collected at 42 days post-fertilization to mimic cattle grazing exposure. Biomass was estimated as dry matter yield per hectare and nitrates were measured by ion chromatography and expressed as parts per million (ppm) on dry matter content. No significant difference in biomass was observed between urea application rates; however, all treated plots produced more biomass than non-treated plots (mean 2.14 vs 1.12 Tons/ha, p<0,05). Mean ± SEM concentrations of NO3 for all time intervals combined increased from 369 ± 216 ppm with no fertilization, to 878 ± 881 ppm at the highest application rate. In spite of the large variation within each group, the highest NO3 level attained was 5600 ppm NO3, which are considered safe for cattle consumption. It can be concluded that nitrate levels in kikuyu pastures fertilized with 4 times the usual rate of nitrogen did not accumulate to pose a health risk in cattle; however, other factors that could also influence nitrate accumulation were not determined in this study.

Resumen La fertilización es uno de los factores que contribuye a la acumulación de nitratos en el pasto kikuyo (Cenchrus clandestinus) en el trópico. Este estudio, realizado entre diciembre de 2012 y junio de 2013 en la Hacienda Paysandú de la Universidad Nacional, ubicada en Santa Elena-Medellín (Antioquia), evaluó la influencia de la fertilización con nitrógeno sobre la producción y las concentraciones de nitratos. El diseño experimental fue en bloques de 4 x 4 con cuatro repeticiones de parcelas monocultivo de pasto kikuyo. Los tratamientos fueron cuatro niveles de nitrógeno aplicado como gránulos de urea sobre la superficie (0, 50, 100 y 200 kg/ha por corte). Las muestras de pasto completo (hojas y tallos) se colectaron a los 42 días posfertilización, con el fin de simular la exposición al pastoreo con ganado. La biomasa se midió como la producción de materia seca por hectárea; los nitratos se midieron por cromatografía iónica, expresada en partes por millón (ppm) sobre el contenido de materia seca. No hubo diferencia significativa en la producción de biomasa entre las diferentes tasas de aplicación de urea; sin embargo todas las parcelas tratadas produjeron más biomasa comparadas con las parcelas no tratadas (promedio 2.14 vs 1.12 ton/ha, p<0,05). Las concentraciones promedio ± SEM de NO3 para todos los tiempos de muestreo combinados, se incrementaron de 369 ± 216 ppm sin fertilización a 878 ± 881 ppm con la más alta tasa de fertilización aplicada. A pesar de la gran variación dentro de cada grupo, los niveles más altos de NO3 obtenidos fueron de 5600 ppm NO3, los cuales se consideran seguros para el consumo en ganado. Se puede concluir que los niveles de nitrato en el pasto kikuyu fertilizado con cuatro veces la tasa normal de nitrógeno, no se acumulan como para plantear un riesgo para la salud en el ganado. Sin embargo, es importante señalar que otros factores que pueden influir en la acumulación de nitratos no se evaluaron en este estudio.

Resumo A adubação é um dos fatores que contribuem na acumulação de nitratos da pastagem kikuyo (Cenchrus clandestinus) do trópico. Este estudo foi realizado entre dezembro de 2012 e junho de 2013 na fazenda Paysandu da Universidade Nacional da Colômbia, localizada no corregimento Santa Elena da cidade de Medellín, Antioquia. Avaliou-se a influência da adubação com nitrogênio sobre a produção e as concentrações de nitratos. O desenho experimental foi de blocos de 4 x 4 com quatro repetições nas parcelas da monocultura de pastagem kikuyo. Os tratamentos foram quatro níveis de nitrogênio aplicado como grânulos de uréia sobre a superfície (0, 50, 100 e 200 kg/ha por safra). As amostras da pastagem completa (folhas e talhos) coletaram-se aos 42 dias após adubação, com o intuito de simular a exposição ao pastoreio com gado. A biomassa mediou-se com a produção de matéria seca por hectare; os nitratos mediram-se por cromatografia iônica, expressada em partes por milhão (ppm) sobre o conteúdo de matéria seca. Não houve diferença significativa na produção de biomassa entre as diferentes taxas de aplicação de uréia; embora, todas as parcelas experimentais produziram maior biomassa comparada com as parcelas não tratadas (media 2.14 vs 1.12 ton/ha, p<0,05). As concentrações medias ± SEM de NO3 para todos os tempos de amostragem combinadas, se incrementaram de 369 ± 216 ppm sem adubação até 878 ± 881 ppm com a maior adubação aplicada. Ainda que houve grande variação dentro de cada grupo, os níveis maiores de NO3 obtidos foram de 5600 ppm NO3, os quais se consideram seguros para o consumo do gado. Pode-se concluir que os níveis de nitrato na pastagem kikuyo adubado com quatro vezes a taxa normal de nitrogênio, não apresentam acumulação como para ter um risco de saúde quando é consumido pelo gado. Embora, outros fatores são importantes para ter em conta, pois eles podem influir na acumulação de nitratos que não foram avaliados neste estudo.

Ameliorative Effects of Alcohol on Human Diabetic Volunteers – A Prospective Study.

Aims: The purpose of this study is to assess and confirm the ameliorative effects of alcohol consumption on biochemical indices of blood i.e., blood glucose, HbA1c, NO2, NO3, lipid profiles, hs-CRP (high sensitive C–Reactive protein) and membrane lipid peroxidation of diabetics. Study Design: Pre-clinical and Biochemical experimental study. Place and Duration of Study: Department of Biochemistry, Acharya Nagarjuna University and Dept. of Biotechnology, K L University, Guntur, A.P and Dept. of Biochemistry, Katuri Medical College, Katuri Nagar, Guntur, A.P and Dept. of Biochemistry, Sri Krishna Devaraya University, Anantapur, A.P and Dept. of Basic Sciences, Madanapalle Institute of Technology and Science (MITS), Post Box No: 14, Angallu (V), Madanapalle, A. P., India, during 2008– 2013. Methodology: The study is conducted on 4 groups (n= 1200) of people of different ages ranging from 35 to 50 years at community health centers in Prakasam, Warangal, Srikakulam districts of Andhra Pradesh, India. The first group consists of type-II diabetic patients who have been consuming alcohol (arithmetic mean ranging from 14.16 to 31.61ml/day) moderately for the past 3 to 10 years. The second group consists of nondiabetic, moderately alcohol consuming healthy individuals. The third group consists of patients who are type-II diabetics (who do not drink) taking medical treatment for minimum period of 1 year. The fourth group consists of non-drinking, non-diabetic healthy individuals. Relationships of alcohol intake with lipid profile, hs-CRP and HBA1c are compared among the three groups. Results: In lipid profile analysis of moderately drinking diabetic group, the HDL levels are found to be higher while the remaining factors such as total cholesterol, LDL, VLDL (P<0.05), triglycerides (P<0.01) and membrane lipid peroxidation are significantly lower. Fasting serum glucose levels are lowered, while serum nitrites and nitrates are found to be significantly higher. These differences are not found in abstainers group and Diabetic group who do not drink. Conclusion: Moderate consumption of alcohol in diabetic individuals is found to have an inverse association with the risky factors like LDL cholesterol, Triglycerides, etc. that are the etiological factors for some of the sequelae of diabetes mellitus i.e., coronary heart diseases, Retinopathy, etc. and has a direct association with the positive factors such as HDL and nitric oxide production. Experimental results are very significant and indicate that moderate consumption of alcohol has ameliorative effects on diabetics.

Evaluación de los métodos de la normatividad mexicana para la determinación de nitritos en alimentos infantiles

Se evaluaron los dos métodos para la determinación de nitritos, que solicita la normatividad mexicana, en alimentos infantiles cárnicos con verduras. Se determinó el contenido de nitritos a los alimentos infantiles, materias primas y productos intermedios del proceso de elaboración; en cada corrida analítica se incluyeron un blanco de reactivos y una muestra testigo; además se determinó la sensibilidad, porcentaje de recuperación y precisión de las metodologías. Los resultados en los alimentos infantiles indicaron una importante diferencia en los contenidos de nitritos obtenidos entre las metodologías, debido a la persistente presencia de turbidez en los extractos. Se propusieron diferentes tratamientos físicos para eliminarla, pero únicamente la redujeron; tal turbidez se atribuyó a los hidratos de carbono; las concentraciones de nitritos informadas presentaron una dispersión grande y estuvieron por debajo del límite de cuantificación de ambos métodos, por lo que no es recomendable la aplicación de estas técnicas para alimentos que se sospechan contienen trazas de nitritos.

Evaluation of the methods for the determination of nitrites in baby foods according Mexican legislation. We evaluated the two methods accepted by the Mexican norm for the determination of nitritesin infant meatbased food with vegetables. We determined the content of nitrites in the infant food, raw materials as well as products from the intermediate stages of production. A reagent blank and a reference sample were included at each analytical run. In addition, we determined the sensitivity, recovery percentage and accuracy of each methodology. Infant food results indicated an important difference in the nitrite content determined under each methodology, due to the persistent presence of turbidity in the extracts. Different treatments were proposed to eliminate the turbidity, but these only managed to reduce it. The turbidity was attributed to carbohydrates which disclosed concentration exhibit a wide dispersion and were below the quantifiable limit under both methodologies; therefore it is not recommended to apply these techniques with food suspected to contain traces of nitrites.

Contribución deuun afluente tributario a la eutrofización del lago de tota (boyacá, Colombia) / Cotribution of aa tributary stream to eutrophication of lake tota (boyacá, Colombia) / Contribuição d aafluentes à eutrofização do lago tota (boyacá, Colômbia)

El objetivo de este estudio fue caracterizar fisicoquímicamente la corriente Las Cintas, afluente al lago de Tota, ubicado en el departamento de Boyacá. Se determinaron los parámetros de temperatura, pH, conductividad, oxígeno disuelto, DQO, DBO5, concentración de especies de nitrógeno (nitratos y nitritos) y concentración de especies de fósforo (fósforo total, fósforo hidrolizable total, ortofosfato total y fósforo orgánico total), para lo cual se efectuaron seis muestreos entre septiembre y noviembre del 2009, en cinco puntos seleccionados sobre la corriente. Estos análisis se realizaron siguiendo metodologías normalizadas para el análisis de aguas. En los resultados se observan comportamientos de poca variabilidad en los parámetros de temperatura, pH, conductividad y oxígeno disuelto; en cuanto al aporte de nitratos, se determinó que el desarrollo de cultivos en las proximidades de la corriente aumenta la concentración de estos iones, que pueden ser arrastrados al lago. Respecto a las diferentes especies de fósforo evaluadas permiten establecer la escasa contribución de fósforo orgánico hacia el cuerpo de agua, además del aporte significativo de fósforo por detergentes vertidos en la corriente. Basándose en la caracterización efectuada, se puede establecer que la actividad agrícola aporta nutrientes que probablemente favorecen el desarrollo del proceso de eutrofización en el lago de Tota.

The aim of this study was to characterize physicochemically “Las Cintas” stream located at Tota Lake, Boyacá department. Temperature, pH, conductivity, dissolved oxygen, COD, BOD5, concentration of nitrogen (nitrates and nitrites) and phosphorus (total phosphorus, total hydrolysable phosphorous, total orthophosphate and total organic phosphorus) were measured. To perform the characterization, samples were collected in six sampling dates, between September and November of 2009, at five points selected along the stream. The analyses were carried out following normalized procedures for water analysis. The results obtained show little changes in temperature, pH, conductivity and dissolved oxygen behavior; Nitrate values indicating that the proximity of the crops to the stream, rises the concentration of these ions, which can be carried to the Lake by run off; The different phosphorous species evaluated allow to establish the highest contribution of organic phosphorus towards the water body, and the input of phosphorous by detergents spilled in the stream. With results it can be established that onions crops provides nutrients which probably support eutrophication processes at the Lake Tota.

O objetivo deste estudo foi caracterizar aphysicochemically afluente do Lago Tota localizada no departamento de Boyacá, e afluente do Lago Tota. Para determinar os parâmetros de temperatura, pH, condutividade elétrica, oxigênio dissolvido, DQO, DBO5 concentração de espécies de nitrogênio (nitrato e nitrito) e da concentração de fósforo de espécies (fósforo total, fósforo hidrolisável total, fósforo total e ortofosfato orgânico total) para os quais seis amostras foram realizadas entre setembro e novembro de 2009 em cinco pontos selecionados no fluxo. Estes testes foram realizados de acordo com metodologias padronizadas para análise de água. Os resultados de comportamento, de pouca variabilidade nos parâmetros de temperatura, pH, condutividade e oxigênio dissolvido na ingestão de nitrato, foi determinado que o desenvolvimento das culturas nas proximidades do córrego aumenta a concentração destes íons pode sendo jogado no lago, enquanto que as diferentes espécies de fósforo possível estabelecer a baixa contribuição de fósforo orgânico o corpo de água, além de significativa contribuição das descargas de fósforo em detergente no córrego. Com base na caracterização realizada, você pode definir que a agricultura fornece nutrientes que estimulam o desenvolvimento da eutrofização no Lago Tota.

Medición de nitratos y nitritos en agua y saliva de población rural precordillerana de la VIII región / Nitrate and nitrite in water and saliva of rural population in the Andes foothills of the VIII Region

Introducción: Un factor de riesgo para las neoplasias escamosas de faringe son las nitrosaminas, las que derivan de los nitratos salivales que provienen de la dieta y en especial del agua si los niveles están por sobre la norma. Objetivos: Conocer y comparar los niveles de nitratos y nitritos en agua y saliva de habitantes de la región precordillerana y en población urbana de Concepción. Material y método: Estudio prospectivo, tipo caso y control. Determinan niveles de nitratos y nitritos en agua de la zona precordillerana y en agua de Concepción y en saliva de habitantes de la zona rural y de grupo control de Concepción. Resultados: Se obtienen 10 muestras de agua del sector rural y 1 muestra de agua potable de Concepción. Nivel de nitratos en agua rural 23,29 mg/L, en agua urbana 3,6 mg/L (p <0,05). En saliva, grupo estudio (n =15) con nivel de nitritos de 9,58 mg/ml, grupo control (n =24) nivel de 3,8 mg/ml (p <0,05). Conclusión: En la zona rural hay niveles significativamente mayores de nitratos en el agua y nitritos en saliva. Los niveles en agua son superiores a normas nacionales e internacionales. Nuestros resultados resaltan la posible importancia de las nitrosaminas y sus precursores como elementos carcinogónicos en los carcinomas escamosos orofaríngeos.

Introduction: A risk factor for squamous carcinomas of the oropharynx are the nitrosamines, which are derived from salivary nitrate coming from diet and water, especially if the levels are above the allowed levels. Aim: To determine and compare the levels of nitrates and nitrites in drinking water and saliva of people at the foothills of our region and urban population of Concepcion. Material and method: A descriptive cross sectional study. Determination of levels of nitrates and nitrites in drinking water in the Andean foothills and Concepcion and in saliva of people from same locations. Results: We obtained 10 rural water samples and 1 from Concepcion drinking water. Nitrate levels in rural water were 23.29 mg/L and 3.6 mg/L (p <0.05) in urban water. In saliva, the study group (n =15) had 9.58 mg/ml nitrite in saliva, the control group (n =24) 3.8 mg/ml (p <0.05). Conclusion: In rural areas there are significantly higher levels of nitrates in drinking water and saliva. The water levels are higher than national and international standards. Our results confirm high amounts of nitrogen cycle products (nitrites and nitrates) in drinking water and in saliva so it could be considered as carcinogenic elements in oropharyngeal squamous cell carcinomas.

Nitrite exhaled breath condensate study in patients undergoing cardiopulmonary bypass cardiac surgery / Estudo do nitrito do condensado do exalado pulmonar em pacientes submetidos à cirurgia cardíaca com CEC

BACKGROUND: There is a relative lack of studies on postoperative changes in nitrite (NO2 - ) concentrations, a marker of injury, following cardiac surgery. In this context, investigations on how exhaled NO concentrations vary in the postoperative period of cardiac surgery will certainly contribute to new clinical findings. OBJECTIVE: The objective of this study was to compare the EBC NO levels in both the pre and postoperative (24 hours) periods of cardiac surgery. METHODS: Twenty - eight individuals were divided into three groups: 1) control, 2) coronary artery bypass grafting, and 3) valve surgery. The nitrite (NO2 - ) levels were measured by chemiluminescence in blood samples and exhaled breath condensate (EBC). Data were analyzed by the Mann - Whitney and Wilcoxon tests. RESULTS: 1) Preoperatively, the EBC NO2 - levels from groups 2 and 3 patients were higher than control individuals; 2) The postoperative (24 hours) NO2 - levels in the EBC from group 3 patients were lower compared with preoperative values; 3) The NO2 - levels in the plasma from group 2 patients were lower in the preoperative compared with the postoperative (24h) values and; 4) Preoperatively, there was no difference between groups 2 and 3 in terms of plasma NO2 - concentrations. CONCLUSION: These data suggest that NO measurement in EBC is feasible in cardiac surgery patients.

INTRODUÇÃO: Estudos mostrando alterações das concentrações de nitrito (NO2 - ) exalado, com biomarcador de lesão, são raros em pacientes submetidos à cirurgia cardíaca. Nesse contexto, o seu estudo no pré e pós - operatório de cirurgias cardíacas poderá contribuir para novos dados clínicos. OBJETIVO: O objetivo foi comparar os níveis de nitrito (NO2 - ) do condensado do exalado pulmonar (CEP) no pré e pós - operatório de cirurgia cardíaca com circulação extracorpórea. MÉTODOS: Vinte e oito indivíduos foram alocados em três grupos: 1) controle, 2) revascularização do miocárdio e 3) correção valvar. Os níveis de NO2 - foram dosados por quimioluminiscência em amostras de CEP e sangue. Os dados foram analisados pelos testes Mann - Whitney e Wilcoxon. RESULTADOS: 1) Os níveis de NO2 - no CEP dos grupos 2 e 3 no pré - operatório foram superiores aos do grupo controle; 2) Os níveis de NO2 - no CEP do Grupo 3 foram maiores no pré que no pós - operatório 24h; 3) Os níveis de NO2 - plasmático do Grupo 2 foram menores no pré que no pós - operatório 24h e; 4) Não houve diferença na concentração de NO2 - plasmático entre os grupos 2 e 3 no pré - operatório. CONCLUSÕES: Esses dados sugerem que a dosagem de NO2 - no CEP é viável em pacientes submetidos à cirurgia cardíaca.

Aceptabilidad del tratamiento empírico de la infección urinaria aguda en el niño / Acceptability of the «empirical» treatment of acute urinary infection in children

Las guías propuestas por grupos internacionales enfatizan en la importancia del diagnóstico de la infección del tracto urinario en la atención primaria de salud, para poder iniciar un tratamiento precoz con antibióticos en los casos de mayor riesgo. El médico de atención primaria en ocasiones realiza su trabajo lejos de los laboratorios de microbiología y no puede realizar el urocultivo con la rapidez necesaria para un tratamiento adecuado. Este médico necesita disponer de pruebas diagnósticas rápidas que le ayuden a tomar la decisión médica más adecuada, aunque ninguna combinación de ellas puede sustituir al urocultivo. En esta propuesta se analizan las situaciones en las que el médico debe esperar el resultado del estudio bacteriológico y en las que puede iniciar un tratamiento empírico después de tomar la muestra para el urocultivo, si este puede realizarse. En los casos excepcionales de imposibilidad de realizar el estudio bacteriológico, el médico tiene que actuar utilizando los llamados métodos de diagnóstico rápido

The guidances proposed for international groups emphasize the significance of diagnosis of the urinary tract infection in primary health care to start an early antibiotics treatment in cases of a major risk. The primary care physician sometimes works far from the microbiology laboratories and can not to carry out a fast uroculture for an appropriate treatment. This physician needs to have available fast diagnostic tests helping him to make a more suitable medical decision, although any combination of them may to replace the uroculture. In present proposal are analyzed those situations where the physician must to await for bacteriological study results to start the empirical treatment after the sample take for uroculture if it may to be carry out. In exceptional cases of impossibility to conduct the bacteriological study, the physician must to act using the so called fast diagnosis methods

Exhaled breath condensate collection for nitrite dosage: a safe and low cost adaptation / Coleta do condensado do ar exalado pulmonar para a dosagem de nitrito: Uma adaptação segura e barata

Purpose: Standardization of a simple and low cost technique of exhaled breath condensate (EBC) collection to measure nitrite. Methods: Two devices were mounted in polystyrene boxes filled either with crushed ice/salt crystals or dry ice/crushed ice. Blood samples were stored at -70º C for posterior nitrite dosages by chemiluminescence and the Griess reaction. Results: a) The use of crushed ice/dry ice or salt revealed sufficient EBC room air collection, but was not efficient for patients under ventilation support; b) the method using crushed ice/salt collected greater EBC volumes, but the nitrite concentrations were not proportional to the volume collected; c) The EBC nitrite values were higher in the surgical group using both methods; d) In the surgical group the nasal clip use diminished the EBC nitrite concentrations in both methods. Conclusions: The exhaled breath condensate (EBC) methodology collection was efficient on room air breathing. Either cooling methods provided successful EBC collections showing that it is possible to diminish costs, and, amongst the two used methods, the one using crushed ice/salt crystals revealed better efficiency compared to the dry ice method.

Objetivo: Padronizar técnica simples e barata de coleta do condensado do ar exalado pulmonar (CEP) para medir nitrito. Métodos: Dois dispositivos foram montados em caixas de isopor e preenchidos com gelo picado/sal grosso ou gelo picado/gelo seco. Amostras de sangue foram armazenadas a -70º C para dosagem de nitrito por quimiluminescência e pela reação de Griess. Resultados: a) a utilização de gelo picado/gelo seco ou sal foi eficiente para a coleta em respiração espontânea, mas ineficiente durante ventilação mecânica; b) o método gelo picado/sal coletou volumes maiores, sem aumento proporcional do nitrito; c) os valores do nitrito foram mais elevados no grupo cirúrgico utilizando os dois métodos; d) no grupo cirúrgico com clipe nasal ocorreu diminuição do nitrito em ambos os métodos. Conclusões: A metodologia do condensado do ar exalado pulmonar (CEP) foi eficiente na coleta respirando em ar ambiente. Os dois métodos de congelamento foram eficientes mostrando que é possível diminuir os custos, e, entre os dois métodos utilizados, o uso de gelo picado/sal mostrou melhor eficiência quanto ao volume da coleta do CEP em comparação com o uso de gelo seco.

Os nitritos são importantes na gênese do adenocarcinoma associado ao esôfago de Barrett? / Are the nitrites important in a genesis of the adenocarcinoma associated to the Barrett esophagus?

RACIONAL: O esôfago de Barrett é complicação do refluxo gastroesofágico e predispõe ao surgimento do adenocarcinoma, sendo que vários fatores têm sido relacionados à sua etiopatogenia. OBJETIVO: Analisar o modelo experimental de refluxo duodenogastroesofágico e a ingestão de solução de nitrito de sódio na gênese do adenocarcinoma associado ao esôfago de Barrett. MÉTODOS: Sessenta ratos machos Wistar foram divididos em quatro grupos, com 20 animais controles não operados (10 animais ingeriram somente água e 10 água mais solução de nitrito de sódio) e 40 animais submetidos à anastomose duodenogastroesofágica látero-lateral (20 animais ingeriram somente água e 20 animais ingeriram água mais solução de nitrito de sódio). A ocorrência de esofagite, metaplasia, displasia, esôfago de Barrett e adenocarcinoma associado foram analisados. A classificação de Viena para displasia e adenocarcinoma foi empregada na análise dos resultados. RESULTADOS: Após 42 semanas de observação, nos animais operados sem ingestão de nitritos o esôfago de Barrett foi registrado em 26,3 por cento (5/19), enquanto no grupo operado associado à ingestão de nitritos, foi encontrado em 72,3 por cento (13/18) dos animais, sendo que neste grupo também foi encontrado seis adenocarcinomas (33,3 por cento). Nenhum animal não operado apresentou o esôfago de Barrett. As categorias 2, 3 e 5 da classificação de Viena somente foram encontradas nos animais operados que ingeriram nitrito de sódio (66,7 por cento). CONCLUSÃO: A ingestão de nitrito de sódio associado ao refluxo duodenogastroesofágico têm importante participação na gênese do adenocarcinoma associado ao esôfago de Barrett.

BACKGROUND: Barrett's esophagus is a complication of gastroesophageal reflux and predisposes to adenocarcinoma of the esophagogastric transition and several factors have been related to its pathogenesis. AIM: To evaluated the genesis of adenocarcinoma associated with Barrett's esophagus in an experimental model of duodenogastroesophageal reflux with the additional ingestion of sodium nitrite METHODS: Sixty male Wistar rats were divided into four groups. Twenty of these animals served as controls (10 animals ingesting only water and 10 ingesting water plus a solution of sodium nitrite), while the remaining 40 animals were submitted to side-to-side duodenogastroesophageal anastomosis (20 animals ingesting only water and 20 ingesting water plus the sodium nitrite solution). The occurrence of esophagitis, metaplasia, dysplasia, Barrett's esophagus associated with adenocarcinoma were analyzed. The Vienna classification for dysplasia and adenocarcinoma was used in the analysis of results. RESULTS: After 42 weeks of observation, Barrett's esophagus was found in 26.3 percent (5/19) of the animals only submitted to surgery compared to 72.3 percent (13/18) of the animals in the group submitted to surgery and given nitrites. Six cases of adenocarcinoma (33.3 percent) were also found in this latter group. Categories 2, 3 and 5 of the Vienna classification were only found in animals submitted to surgery plus sodium nitrite (66.7 percent). CONCLUSION: The ingestion of sodium nitrite associated with duodenogastroesophageal reflux plays an important role in the genesis of adenocarcinoma associated with Barrett's esophagus.

Tyrosine nitration site specificity identified by LC/MS in nitrite-modified collagen type IV

Non-enzymatic nitrite induced collagen cross-linking results in changes reminiscent of age-related damage and parallels the well-known model system, non-enzymatic glycation. We have recently observed that nitrite modification of basement membrane proteins can induce deleterious effects on overlying retinal pigment epithelial cells in studies relevant to age-related macular degeneration. The present work was undertaken in order to confirm 3-nitro-tyrosine (3-NT) as a product of the reaction and to identify the site specificity of nitration in collagen IV, a major component of basement membranes. Human collagen type IV was modified via incubation with 200 mM NaNO2 (pH=7.38) for one week at 37degrees C. The modified protein was prepared in 2 different ways, including acid hydrolysis and trypsin digestion for site specificity determination. The samples were analyzed by LC/MS using a C12 RP column. Site specificity was determined from tandem MS/MS data utilizing TurboSEQUEST software and the Swiss-Prot sequence database. 3-NT was detected in protein digests and acid hydrolysates of nitrite modified collagen IV. Positive identification with standard 3-NT was confirmed by identical Rt, lambda(max)=279 nm and 355 nm, and m/z=227. Analyses of tryptic digests identified four sites of tyrosine nitration, alpha1(IV)Y348, alpha1(IV)Y534, alpha2(IV)Y327, and alpha2(IV)Y1081. These sites are located in the triple-helical region of the protein and provide clues regarding potential sites for nitrite modification in collagen type IV.

Effect of Hours of Use of Drinking Machine on Drinking Water Quality / 环境与健康杂志

Objective To know the effect of hours of use of the drinking machine on drinking water quality. Methods The hours of use of the drinking machine were 1week, 2, 5, 10, 12, 36 and 60 months, the water samples collected at different hours of use was determined by routine test methods of water quality. Results The total bacteria count and nitrite in drinking water exceeded the standard limits and the two indexes increased as the hours of use of the drinking machine lasted. At the first-using of drinking-machine, the total bacteria count and coliform count exceeded the standard limits seriously. Conclusion In order to ensure the drinking water safety,water should be boiled before drinking and the drinking-water-producing factories should improve the production and management. Cleaning and disinfection of the inner components of drinking water machine should be paid more attetion to.