Navegando por Palavras-chave "Citrate"
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- ItemAcesso aberto (Open Access)Avaliação da citratemia em pacientes com lesão renal submetidos a hemodiafiltração venovenosa contínua e anticoagulação regional pelo citrato: uma comparação entre indivíduos com e sem disfunção hepática(Universidade Federal de São Paulo (UNIFESP), 2018-04-04) Santos, Thais Oliveira Claizoni dos [UNIFESP]; Durão, Marcelino de Souza [UNIFESP]; http://lattes.cnpq.br/2520100158218531; http://lattes.cnpq.br/9346391293160338Objetivos: Avaliar os níveis séricos de citratemia em pacientes submetidos à hemodiafiltração venovenosa contínua ( HDFVVC) e anticoagulação regional pelo citratro (A RC), comparando pacientes com e sem disfunção hepática (DH); correlacionar a medida do nível de citrato (Ci) com a razão das medidas do cálcio total pelo cálcio iônico sistêmico e outros marcadores de disfunção hepática; avaliar variações do perfil eletrolítico e ácido base e de parêmetros relacionados à diálise. Metodologia: estudo prspectivo observacional em uma unidade d e t erapia intensiva ( UTI) de hospital privado, comparando dados clínicos e laboratoriais de pacientes submetidos à HDFVVC com e sem DH, incluindo a concentração sérica do citrato. DH foi definida como uma razão normatizada internacional (RNI) ≥ 2,5. O citrato trissódico a 4% foi infundido no circuito de diálise para manter o cálcio iônico pós filtro entre 0 ,25 0,35mmol/ L. Pacientes com DH tiveram a infusão de citrato fixada a 17mmol/h, independente do valor do cálcio iônico pós filtro. Resultados: Duzentos pacientes foram avaliados ( 62 c om D H). O grupo DH apresentou uma maior mortalidade (69,4% vs 52,2%, p = 0,023). O Ci foi significativamente maior no grupo DH em todos os dias avaliados. O grupo DH apresentou níveis basais mais elevados de RNI (mediana 2,68 vs 1,42, p < 0,001) e lactato arterial (mediana 34 vs 16mEq/L, p < 0,001) e níveis séricos mais baixos de bicarbonato (mediana 15,8 vs 19,4mEq/L, p < 0,001), com achados semelhantes nos outros dias do estudo, quando comparados com o grupo sem DH. Não houve diferença estatisticamente significativa em relação ao cálcio iônico sistêmico nos dois grupos. O grupo com DH recebeu um maior número de transfusão de glóbulos vermelhos (mediana 3 vs 1, p < 0,001). Não houve diferenças entre os grupos em relação à dose fornecida de diálise (33ml/kg/h), número de filtros usados e tempo total de diálise. Analisando a relação entre o Ci e a razão cálcio total/cálcio iônico, encontramos uma correlação positiva fraca, com o maior coeficiente de correlação d e 0 ,354. Encontramos r elação igualmente positiva, mas fraca, quando avaliamos citratemia e valor de R NI, transaminases, bilirrubina total elactato arterial. A citratemia se mostrou como fator de risco independente para o óbito, com OR 11,3 (IC 95% 2,74 46,8). Conclusão: Apesar de ter níveis séricos de Ci significativamente m aiores, o g rupo D H não mostrou sinais de acúmulo, especialmente hipocalcemia iônica. Houve uma correlação insatisfatória entre níveis de citrato, RNI e razão cácio total/cálcio iônico (um preditor de toxicidade pelo citrato).
- ItemSomente MetadadadosEarly Diagnosis of Prostate Cancer by Citrate Determination in Urine with Europium-Oxytetracycline Complex(Soc Applied Spectroscopy, 2012-08-01) Silva, Flavia R. O. [UNIFESP]; Nabeshima, Camila Tiemi [UNIFESP]; Bellini, Maria H.; Courrol, Lilia C. [UNIFESP]; Universidade Federal de São Paulo (UNIFESP); IPEN CNEN SPNormal prostate tissue contains high levels of citrate. in the presence of prostate cancer, the citrate level is diminished. in this paper we show that it is possible to use europium oxytetracycline complex as a citrate fluorescent probe and consequently as a prostate cancer probe. We analyzed normal nude male mice urine and urine from nude male mice in which prostate cancer was induced by intraprostatic inoculation of DU145 cells. the urine samples were collected from the animals at the 7th, 14th, 21st, and 35th days after the surgery procedures. the intensity of europium emission at 615 nm in europium oxytetracycline complex in the presence of citrate increases linearly. the citrate concentrations were determined from a calculated calibration curve. A concentration decrease in malignant prostate urine from the normal (PBS group) urine value from similar to 8.0 mM to similar to 2.4 mM (tumor group at 35th day) was found. the obtained results indicated that europium oxytetracycline provides a significant biomarker for prostate cancer detection with a direct, accurate, noninvasive, and non-enzymatic method for measurement of citrate in biological fluids.
- ItemSomente MetadadadosOptimum Nutrition for Kidney Stone Disease(Elsevier B.V., 2013-03-01) Heilberg, Ita P.; Goldfarb, David S.; Universidade Federal de São Paulo (UNIFESP); NYU; New York Harbor VA Hlth Care SystWe summarize the data regarding the associations of individual dietary components with kidney stones and the effects on 24-hour urinary profiles. the therapeutic recommendations for stone prevention that result from these studies are applied where possible to stones of specific composition. Idiopathic calcium oxalate stone-formers are advised to reduce ingestion of animal protein, oxalate, and sodium while maintaining intake of 800 to 1200 mg of calcium and increasing consumption of citrate and potassium. There are few data regarding dietary therapy of calcium phosphate stones. Whether the inhibitory effect of citrate sufficiently counteracts increasing urine pH to justify more intake of potassium and citrate is not clear. Reduction of sodium intake to decrease urinary calcium excretion would also be expected to decrease calcium phosphate stone recurrence. Conversely, the most important urine variable in the causation of uric acid stones is low urine pH, linked to insulin resistance as a component of obesity and the metabolic syndrome. the mainstay of therapy is weight loss and urinary alkalinization provided by a more vegetarian diet. Reduction in animal protein intake will reduce purine ingestion and uric acid excretion. for cystine stones, restriction of animal protein is associated with reduction in intake of the cystine precursor methionine as well as cystine. Reduction of urine sodium results in less urine cystine. Ingestion of vegetables high in organic anion content, such as citrate and malate, should be associated with higher urine pH and fewer stones because the amino acid cystine is soluble in more alkaline urine. Because of their infectious origin, diet has no definitive role for struvite stones except for avoiding urinary alkalinization, which may worsen their development. Published by Elsevier Inc. on behalf of the National Kidney Foundation, Inc.
- ItemSomente MetadadadosSimplified estimates of ion-activity products of calcium oxalate and calcium phosphate in mouse urine(Springer, 2012-08-01) Tiselius, Hans-Goran; Nogueira Ferraz, Renato Ribeiro [UNIFESP]; Heilberg, Ita Pfeferman [UNIFESP]; Karolinska Inst; Universidade Federal de São Paulo (UNIFESP)This study aimed at formulating simplified estimates of ion-activity products of calcium oxalate (AP(CaOx)) and calcium phosphate (AP(CaP)) in mouse urineto find the most important determinants in order to limit the analytical work-up. Literature data on mouse urine composition was used to determine the relative effect of each urine variable on the two ion-activity products. AP(CaOx) and AP(CaP) were calculated by iterative approximation with the EQUIL2 computerized program. the most important determinants for AP(CaOx) were calcium, oxalate and citrate and for AP(CaP) calcium, phosphate, citrate, magnesium and pH. Urine concentrations of the variables were used. A simplified estimate of AP(CaOx) (AP(CaOx)-index(MOUSE)) that numerically approximately corresponded to 10(8) x AP(CaOx) was given the following expression:AP(CaOx)-index(MOUSE) = 0.70 x Calcium(1.05) x Oxalate(0.95)(0.90-0.0225 x Citrate) + (6.6 x 10(-8) x Citrate(3.98))For a series of urine samples with various composition the coefficient of correlation between AP(CaOx)-index(MOUSE) and 10(8) x AP(CaOx) was 0.99 (p = 0.00000). A similar estimate of AP(CaP) (AP(CaP)-index(MOUSE)) was formulated so that it approximately would correspond numerically to 10(14) x AP(CaP) taking the following form:Ap(CaP)-index(MOUSE) = 0.05 x Calcium(1.17) x Phosphate(0.85) x Magnesium(0.18) x (pH - 4.5)(6.8) / Citrate(0.76)For a series of variations in urine composition the coefficient of correlation was 0.95 (p = 0.00000). the two approximate estimates shown in this article are simplified expressions of AP(CaOx) and AP(CaP). the intention of these theoretical calculations was not to get methods for accurate information on the saturation levels in urine, but to have mathematical tools useful for rough conclusions on the outcome of different experimental situations in mice. It needs to be emphasized that the accuracy will be negatively influenced if urine variables not included in the formulas differ very much from basic concentrations.