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Fractional Excretion (fractional + excretion)
Selected AbstractsRenal tubular function in children with ,-thalassemia minorNEPHROLOGY, Issue 5 2005SÜLEYMAN KALMAN SUMMARY: Background: , -thalassemia minor is a common heterozygous haemoglobinopathy that is characterized by both microcytosis and hypochromia. It requires no treatment. It has been postulated that low-grade haemolysis, tubular iron deposition and toxins derived from erythrocytes might cause renal tubular damage in adult patients with , -thalassemia minor. Our aim was to investigate the renal tubular functions in children with ,-thalassemia minor and to determine its possible harmful effects. Methods: The study was conducted on 32 children (14 female and 18 male) at the age of 5.8 ± 3.1 years (range 2,14 years) with , -thalassemia minor. The patients were classified as anaemic (haemoglobin (Hb) , 11 g/dL) (Group 1, n = 14) and non-anaemic (Hb > 11 g/dL) (Group 2, n = 18). A control group was formed with 18 healthy children whose ages and sexes match those in other groups (Group 3, n = 18). Fractional excretion of sodium (FENa, %), fractional excretion of magnesium (FEMg, %), fractional excretion of uric acid (FEUA, %) and tubular phosphorus reabsorption (TPR,%) were calculated with standard formulas. Urinary calcium excretion (mg/kg per 24 h), zinc (Zn) (µg/dL), glucosuria (mg/dL), , -2 microglobulin (mg/dL) and N -acetyl- ,,D-glycosaminidase (NAG, U/mmol creatinine) levels were measured through biochemical methods. Results: There was no statistically significant difference among the three groups in terms of the results of FENa (%), FEMg (%), FEUA (%), TPR (%), calciuria (mg/kg per 24 h), NAG, urine Zn, proteinuria, glucosuria or urine , - 2 microglobulin levels (P > 0.05). Conclusion: On the contrary of children with , -thalassemia major, renal tubular dysfunction has not been determined in children with , -thalassemia minor in the present study. [source] The Role of Exhaled Nitric Oxide in Evaluation of Acute Asthma in a Pediatric Emergency DepartmentACADEMIC EMERGENCY MEDICINE, Issue 1 2009Maria Y. Kwok MD Abstract Objectives:, Fractional excretion of nitric oxide (FENO) has been used as a noninvasive marker to assess and manage chronic asthma in adults and children. The aim of this study was to determine the feasibility of obtaining FENO concentrations in children treated in the emergency department (ED) for acute asthma exacerbation and to examine the association between FENO concentrations and other measures of acute asthma severity. Methods:, This was a cross-sectional study of a convenience sample of children 2,18 years old who were seen in an urban ED for acute asthma exacerbation. Using a tidal breathing method with real-time display, the authors measured FENO concentrations before and 1 hour after the administration of corticosteroids and at discharge from the ED. Outcome measures included pulmonary index score (PIS), hospital admission, and short-term outcomes (e.g., missed days of school). Results:, A total of 133 subjects were enrolled. Sixty-eight percent (95% confidence interval [CI] = 60% to 76%) of the subjects provided adequate breaths for FENO measurement. There was no difference in the median initial FENO concentration among subjects, regardless of the severity of their acute asthma. Most subjects showed no change in their FENO concentrations from the start to the end of treatment. FENO concentrations were not significantly associated with other short-term outcomes. Conclusions:, Measurement of FENO is difficult for a large proportion of children with acute asthma exacerbation. FENO concentration during an asthma exacerbation does not correlate with other measures of acute severity and has limited utility in the ED management of acute asthma in children. [source] Regulation of C-Terminal and Intact FGF-23 by Dietary Phosphate in Men and Women,JOURNAL OF BONE AND MINERAL RESEARCH, Issue 8 2006Sherri-Ann M Burnett MD Abstract FGF-23 is a novel regulator of phosphate metabolism. We studied the regulation of FGF-23 by dietary phosphate in 66 men and women using two assays. Dietary phosphate restriction decreased FGF-23 and loading increased FGF-23 significantly. An assay that measured intact FGF-23 showed the effects of dietary phosphate much more clearly than an assay that also measures presumed biologically inactive fragments. Dietary phosphate is a key regulator of circulating FGF-23; choice of assay is critical when studying FGF-23 physiology. Introduction: Fibroblast growth factor 23 (FGF-23) is a novel phosphaturic factor discovered through genetic studies of patients with renal phosphate wasting disorders. Ablation of the FGF-23 gene in mice reduces renal phosphate excretion and increases serum phosphate, suggesting that FGF-23 is critical for normal phosphate homeostasis. We examined the role of dietary phosphate in the regulation of FGF-23 in humans. Materials and Methods: Sixty-six healthy males and females were randomized to either phosphate-depleted or -loaded diets for 5 days, after a 4-day run-in diet. FGF-23 was measured using an "intact" assay that only detects intact FGF-23 peptide and with a "C-terminal" assay that measures both intact FGF-23 peptide and presumed biologically inactive carboxyl terminal fragments. The main outcome was the within group change in FGF-23 with either phosphate depletion or loading. Results: Using the intact FGF-23 assay, mean FGF-23 area under the curve (AUC) decreased by 9 ± 16% with phosphate depletion (p = 0.0041) and increased by 35 ± 29% with loading (p < 0.0001). Using the C-terminal FGF-23 assay, mean FGF-23 AUC decreased by 8 ± 12% with phosphate depletion (p = 0.0003) and increased by 13 ± 20% with loading (p = 0.0016). Increases in FGF-23 with phosphate loading were greater with the intact assay than with the C-terminal assay (p = 0.0003). Using the intact assay only, FGF-23 was significantly associated with serum phosphate (r = 0.39, p < 0.01), 24-h urinary phosphate (r = 0.47, p < 0.01), fractional excretion of phosphate (r = 0.29, p < 0.01), and 1,25-dihydroxyvitamin D (r = ,0.30, p < 0.01). The association between the assays was weak (r = 0.26, p < 0.01). Conclusions: Dietary phosphate is a key regulator of circulating FGF-23 levels in humans. Additionally, choice of assay is critical when performing physiologic investigations of FGF-23. [source] Protective role of ,-aminobutyric acid against chronic renal failure in ratsJOURNAL OF PHARMACY AND PHARMACOLOGY: AN INTERNATI ONAL JOURNAL OF PHARMACEUTICAL SCIENCE, Issue 11 2006Sumiyo Sasaki The protective effect of ,-aminobutyric acid (GABA) against chronic renal failure (CRF) was investigated using a remnant kidney model with 5/6 nephrectomized rats. Nephrectomy led to renal dysfunction, which was evaluated via several parameters including serum urea nitrogen, creatinine (Cr) and Cr clearance. However, the administration of GABA ameliorated renal dysfunction, and a longer administration period of GABA increased its protective effect. In addition, nephrectomized control rats showed an elevation in the fractional excretion of sodium (FENa) with an increase in urinary sodium, while GABA led to a significant decline in FENa. Moreover, nephrectomy resulted in a decrease of serum albumin and an increase of urinary protein with a change in the urinary protein pattern, whereas the rats administered GABA showed improvement in these changes associated with CRF caused by nephrectomy. This suggests that GABA would inhibit the disease progression and have a protective role against CRF. As one of the risk factors for CRF progression, hypertension was also regulated by GABA. The results also indicate that GABA may play a protective role against CRF through improvement of the serum lipid profile, with reductions in triglyceride and total cholesterol. Furthermore, nephrectomy led to renal oxidative stress with a decrease in the activity of antioxidative enzymes and elevation of lipid peroxidation. The administration of GABA attenuated oxidative stress induced by nephrectomy through an increase in superoxide dismutase and catalase, and decrease in lipid peroxidation. The histopathological lesions, including glomerular, tubular and interstitial lesions, under nephrectomy were also improved by GABA with the inhibition of fibronectin expression. This study demonstrated that GABA attenuated renal dysfunction via regulation of blood pressure and lipid profile, and it also ameliorated the oxidative stress induced by nephrectomy, suggesting the promising potential of GABA in protecting against renal failure progression. [source] Effects of Norepinephrine and Combined Norepinephrine and Fenoldopam Infusion on Systemic Hemodynamics and Indices of Renal Function in Normotensive Neonatal FoalsJOURNAL OF VETERINARY INTERNAL MEDICINE, Issue 5 2008A.R. Hollis Background: Norepinephrine increases arterial blood pressure but may have adverse effects on renal blood flow. Fenoldopam, a dopamine-1 receptor agonist, increases urine output in normotensive foals. The combination of norepinephrine and fenoldopam may lead to improved renal perfusion compared with an infusion of norepinephrine alone. The combined effects of these drugs have not been reported in the horse. Hypothesis: Norepinephrine will alter the hemodynamic profile of foals without affecting renal function. Addition of fenoldopam will change the renal profile during the infusions without changing the hemodynamic profile. Animals: Five conscious pony foals. Methods: Each foal received norepinephrine (0.3 ,g/kg/min), combined norepinephrine (0.3 ,g/kg/min) and fenoldopam (0.04 ,g/kg/min), and a control dose of saline in a masked, placebo-controlled study. Heart rate (HR), arterial blood pressure (direct), and cardiac output (lithium dilution) were measured, and systemic vascular resistance (SVR), stroke volume, cardiac index (CI), and stroke volume index were calculated. Urine output, creatinine clearance, and fractional excretion of electrolytes were measured. Results: Norepinephrine and a combined norepinephrine and fenoldopam infusion increased arterial blood pressure, SVR, urine output, and creatinine clearance and decreased HR and CI compared with saline. The combination resulted in higher HR and lower arterial blood pressure than norepinephrine alone. Conclusions and Clinical Importance: Norepinephrine might be useful for hypotensive foals, because in normal foals, this infusion rate increases SVR without negatively affecting renal function (creatinine clearance increased). Fenoldopam does not provide additional benefit to renal function. These findings warrant further investigation. [source] Octreotide in liver cirrhosis: a salvage for variceal bleeding can be a gunshot for kidneysLIVER INTERNATIONAL, Issue 3 2005Deniz Güney Duman Abstract Background: The renal effects of octreotide, used for bleeding esophageal varices in cirrhosis, are controversial. Methods: Fourteen cirrhotic patients (Child,Pugh; A/B/C: 1/12/1) were enrolled. Plasma nitrite and endothelin (ET) levels, urinary nitrite output, free water clearance (FWC) and fractional excretion of filtered sodium (FENa) were measured and renal Doppler ultrasound was carried out. Octreotide was infused at a rate of 0.75 ,g/kg/h for 3 h after a bolus of 0.75 ,g/kg body weight. All the parameters were reevaluated during octreotide administration while the patients acted as their own controls. Results: Octreotide induced significant reductions in urinary nitrite, FENa and FWC. Plasma ET levels increased (baseline: 6.7 pg/ml, octreotide: 8.4 pg/ml), whereas the plasma nitrite level did not change significantly after octreotide infusion. Overall, no significant change in renal resistive index (RRI) could be demonstrated on Doppler after octreotide administration. However, patients with elevated baseline RRI values had significantly more deterioration in FWC and FENa compared with patients with normal RRI in response to octreotide. Conclusion: A marked decrease in FENa, FWC and urinary nitrite output, together with a significant increase in plasma ET level in response to octreotide, may indicate renal dysfunction in cirrhotic patients. This deleterious renal effect of octreotide may be more enhanced in patients with elevated baseline RRI. [source] Renal tubular function in children with ,-thalassemia minorNEPHROLOGY, Issue 5 2005SÜLEYMAN KALMAN SUMMARY: Background: , -thalassemia minor is a common heterozygous haemoglobinopathy that is characterized by both microcytosis and hypochromia. It requires no treatment. It has been postulated that low-grade haemolysis, tubular iron deposition and toxins derived from erythrocytes might cause renal tubular damage in adult patients with , -thalassemia minor. Our aim was to investigate the renal tubular functions in children with ,-thalassemia minor and to determine its possible harmful effects. Methods: The study was conducted on 32 children (14 female and 18 male) at the age of 5.8 ± 3.1 years (range 2,14 years) with , -thalassemia minor. The patients were classified as anaemic (haemoglobin (Hb) , 11 g/dL) (Group 1, n = 14) and non-anaemic (Hb > 11 g/dL) (Group 2, n = 18). A control group was formed with 18 healthy children whose ages and sexes match those in other groups (Group 3, n = 18). Fractional excretion of sodium (FENa, %), fractional excretion of magnesium (FEMg, %), fractional excretion of uric acid (FEUA, %) and tubular phosphorus reabsorption (TPR,%) were calculated with standard formulas. Urinary calcium excretion (mg/kg per 24 h), zinc (Zn) (µg/dL), glucosuria (mg/dL), , -2 microglobulin (mg/dL) and N -acetyl- ,,D-glycosaminidase (NAG, U/mmol creatinine) levels were measured through biochemical methods. Results: There was no statistically significant difference among the three groups in terms of the results of FENa (%), FEMg (%), FEUA (%), TPR (%), calciuria (mg/kg per 24 h), NAG, urine Zn, proteinuria, glucosuria or urine , - 2 microglobulin levels (P > 0.05). Conclusion: On the contrary of children with , -thalassemia major, renal tubular dysfunction has not been determined in children with , -thalassemia minor in the present study. [source] Prolonged exposure to inhaled nitric oxide transiently modifies tubular function in healthy piglets and promotes tubular apoptosisACTA PHYSIOLOGICA, Issue 4 2009W. Go, dzik Abstract Aim:, Inhaled nitric oxide (iNO) is a selective pulmonary vasodilator. We hypothesized that those piglets exposed to prolonged iNO react with a modified renal function. Methods:, Randomized, placebo-controlled exposure to 40 p.p.m. iNO (30 h) in piglets (n = 20). Plasma and urine were sampled during three periods (first and second 12 h periods, and finally a 6 h period). We measured urine volumes, plasma and urine electrolytes (UNa, UK, UCl), plasma creatinine and urea. We calculated creatinine clearance (Ccr), and fractional excretions of sodium and potassium (FENa, FEK) and urinary excretions of electrolytes (UENa, UEK, UECl). Haemodynamic data were recorded and renal tubular apoptosis detected. Results:, For the first 12 h, certain parameters significantly increased in the iNO group (mean ± SD): UNa (mmol L,1), 87.7 (±35.0) vs. 39.3 (±22.9), UCl (mmol L,1) 80.4 (±32.8) vs. 48.0 (±26.7), FENa (%) 2.1 (±0.8) vs. 0.7 (±0.5), FEK (%) 31.7 (±7.0) vs. 20.7 (±12.3), as well as UENa (mmol) 61.0 (±21.1) vs. 27.6 (±17.9) and UECl (mmol) 57.3 (24.5) vs. 37.6 (29.0). These changes were absent in the second and third periods of the study. Significant differences in percentage of apoptotic cell nuclei in the renal cortex and medulla were found after iNO exposure: 39% vs. 15%. Conclusion:, Exposure to 40 p.p.m. iNO in healthy anaesthetized piglets has a transient natriuretic effect that disappears after 12 h. We also found evidence of renal tubular apoptosis promotion after 30 h of iNO. [source] | ||||||||||