Excretion Values Research Articles

Urinary isoflavonoid excretion as a biomarker of dietary soy intake during two randomized soy trials.

We evaluated urinary isoflavonoid excretion as a biomarker of dietary isoflavone intake during two randomized soy trials (13-24 months) among 256 premenopausal women with a total of 1,385 repeated urine samples. Participants consumed a high-soy diet (2 servings/day) and a low-soy diet (<3 servings/week), completed 7 unannounced 24-hour dietary recalls, and donated repeated urine samples, which were analyzed for isoflavonoid excretion by liquid chromatography methods. We computed Spearman correlation coefficients and applied logistic regression to estimate the area under the curve. Median overall daily dietary isoflavone intakes at baseline, during low- and high-soy diet were 2.3, 0.2, and 60.4 mg aglycone equivalents, respectively. The corresponding urinary isoflavonoid excretion values were 0.4, 1.0, and 32.4 nmol/mg creatinine. Across diets, urinary isoflavonoid excretion was significantly associated with dietary isoflavone intake (rs=0.51, AUC=0.85; p<0.0001) but not within diet periods (rs=0.05-0.06, AUC=0.565-0.573). Urinary isoflavonoid excretion is an excellent biomarker to discriminate between low- and high-soy diets across populations, but the association with dietary isoflavone intake is weak when the range of soy intake is small.

HIV Tat protein affects circadian rhythmicity by interfering with the circadian system.

ObjectivesSleep disorders are common in patients with HIV/AIDS, and can lead to poor quality of life. Although many studies have investigated the aetiology of these disorders, it is still unclear whether impaired sleep quality is associated with HIV itself, social problems, or side effects of antiretroviral therapy (ART). Moreover, despite its known neurological associations, little is known about the role of the trans-activator of transcription (Tat) protein in sleep disorders in patients with HIV/AIDS. The purpose of this study was to test the hypothesis that the sleep quality of patients with HIV/AIDS affected by an altered circadian rhythm correlates with cerebrospinal HIV Tat protein concentration.MethodsNinety-six patients with HIV/AIDS between 20 and 69 years old completed the Pittsburgh Sleep Quality Index. Their circadian rhythm parameters of blood pressure, Tat concentration in cerebrospinal fluid, melatonin concentration, CD4 cell count and HIV RNA viral load in serum were measured.ResultsThe circadian amplitude of systolic blood pressure and the score for sleep quality (Pittsburgh Sleep Quality Index) were negatively correlated with HIV Tat protein concentration, while the melatonin value was positively correlated with Tat protein concentration.ConclusionsThe HIV Tat protein affects circadian rhythmicity by interfering with the circadian system in patients with HIV/AIDS and further increases the melatonin excretion value. A Tat protein-related high melatonin value may counteract HIV-related poor sleep quality during the progression of HIV infection. This study provides the first clinical evidence offering an explanation for why sleep quality did not show an association with progression of HIV infection in previous studies.

Marine and freshwater crab meals in diets for red porgy ( Pagrus pagrus ): Digestibility, ammonia-N excretion, phosphorous and calcium retention

Abstract Two trials were conducted to evaluate the nutrient digestibility of river crab (RC) ( Procambarus clarkii ) and marine crab (MC) ( Chaceon affinis ) meals in diets for red porgy ( Pagrus pagrus ) and the effect on ammonia-N excretion and P and Ca retentions. In trial I, the apparent digestibility coefficient (ADC) of nutrients and energy contents in RC and MC meals were determined. Results showed that, the ADC values for protein, lipids, ash, dry matter and gross energy were significantly higher for MC than for RC meal. Both crab meals were efficiently digested despite their high chitin and ash contents. In trial II, red porgy were fed over 6 months with five diets: a control diet (CD) based on high quality fish meal (FM), and four diets where FM protein was replaced at a rate of 10% or 20% by protein derived from either RC or MC meal (RC10, RC20, MC10 and MC20). Replacement of the FM protein by RC or MC proteins had no effect both on protein utilisation and ammonia-N excretion rates, which ranged from 105 to 119 mg N–NH 4 + kg − 1 day − 1 for all diets. A linear increase was observed in the dietary Ca/P ratio by the increase of the dietary RC and MC meal inclusions, resulting in a reduction in the whole fish body content of P, Ca and ash with interesting similar whole body Ca/P ratio (1.59–1.63) for all treatments. Accordingly, Ca, P and ash retention rates were significantly reduced by increasing the dietary proportion of both crab meals. Moreover, a negative relationship between fish growth and final whole body Ca, P and ash contents was obtained. However, no significant differences were observed in total P excretion value (kg P t − 1 ).

Urinary excretion of calcium, magnesium, phosphate, citrate, oxalate, and uric acid by healthy schoolchildren using a 12-h collection protocol

Improving knowledge about normal urine composition in children is important for early prevention of lithiasis. We describe urinary excretion values of calcium (Ca), magnesium (Mg), phosphate (P), citrate (Cit), uric acid (Ur), and oxalate (Ox) in healthy children with and without a family history of lithiasis, using a 12-h urine collection protocol. Urine samples were obtained from 184 children (5-12 years): a spot sample collected in the afternoon, and a 12-h overnight sample. Solute/creatinine (Cr) and 12-h solute excretion was calculated. Urinary excretion values of the studied solutes are presented as percentile values, separately for each type of sample. Due to age-related differences in the solute/creatinine ratios, except for Ca and Cit, results are described according to the child's age. The presence of excretion values related to an increased risk of lithiasis was more common in children with a family history. We report data from urine samples collected by using a simplified collection protocol. The observed differences between children with and without a family history of lithiasis could justify that in population studies aimed at setting reference values, the former are excluded.

Association of renin-angiotensin system genes polymorphism with progression of diabetic nephropathy in patients with type 1 diabetes mellitus.

Diabetic nephropathy (DN) as a major microvascular complication of diabetes mellitus (DM) include a progressive increase in urinary albumin excretion in association with an increase in blood pressure and to end stage renal failure. Hypertension connected with renin-angiotensin system (RAS) hyperactivity and corresponding genotypes, angiotensinogen (AGT), angiotensine-converting enzyme (ACE) and angiotensin II type 1 receptor (AT1R), predispose the increasing risk of DN. The aim of this study was to assess the distribution of AGT, ACE and AT1R gene polymorphisms in patients with type 1 DM according to the level of DN and patients clinical characteristics. The study included 79 type 1 diabetic patients. Inclusion criteria were: age between 20-40, duration of diabetes > 5 years, and no other severe diseases. Clinical characteristics were gained from interviewing the patients. Polymorphism was detected by polymerase chain reaction (PCR) and restriction fragment length polymorphism using restriction enzymes Psy I (Tth 111 I) and Hae III. The patients with proteinuria compared with normo- and microalbuminuric patients, highly differed in age, diabetes duration, blood pressure level, hypertension, rethynopathy and urinary albumin excretion values (p < 0.001). No statistically significant difference between the groups was found for the ACE and AT1R gene polymorphisms distribution. The presence of TT genotype of the M235T polymorphism was significantly higher in the group with proteinuria (p < 0.05). The patients with hypertension raised nephropathy 5.2 times higher (OR = 5.20, p < 0.05) while carriers of TT allel developed nephropathy 28.38 times higher (OR = 28.389, p < 0.01) than those with MM genotype. Increased association of hypertension and TT angiotensinogen gene polymorphism in patients with diabetes mellitus with proteinuria could be a significant marker of diabetic nephropathy.

Combined Effects of Blood Pressure and Aldosterone on Cardiac Left Ventricular Mass Index—Ethnic Differences between Kazakh, Uygur and Han Subjects

Previous Background: Hemodynamic factors, like blood pressure, have been established to be major determinants of cardiac left ventricular structure. However, several factors other than blood pressure to influence cardiac mass have been implicated. When we did medical survey, cardiac left ventricular mass index (LVMI) of one ethnic group that had higher blood pressure was found to be smaller than that of the other ethnic groups with a lower blood pressure. Such contradicted data from the present study were analyzed combining blood pressure, LVMI and chemical parameters obtained from blood and urine. Methods: In a medical survey conducted in Xinjiang, China, 279 people (65 - 70 years old) from three ethnic groups (Kazakh, Uygur and Han) from two separated regions provided blood and urine samples and underwent echocardiography and 24-h ambulatory blood pressure monitoring (ABPM). Results: Systolic and diastolic blood pressure obtained from ABPM and urinary sodium excretion values were significantly higher in Kazakh than that in Uygur and Han. However, LVMI in Kazakh was lower than that in other 2 groups. Plasma aldosterone concentration (PAC) and plasma renin activity (PRA) were significantly lowest in Kazakh. The values of LVMI in all ethnic groups were positively related to both blood pressure and PAC. An inverse correlation was identified between PAC and urinary sodium excretion value. Conclusion: Although higher blood pressure in Kazakh subjects, their LVMI was lower than those of Uygur and Han, whose blood pressure was lower than that in Kazakh. These results suggest that blood pressure is not always a determinant for LVMI value. There is a possibility that relatively lower PAC resulted from higher sodium intake suppressed the rise in LVMI caused by higher blood pressure in Kazakh.

Increased Nitrogen Retention after Trans-Operative Intravenous Amino Acid and Glucose Infusion, without Changes in Urinary Amino Acid, Adrenaline and Plasma Urea or Glucose

Objective: Nutritional deficiencies are associated with increased morbidity and mortality during and after surgery. The present study evaluated nitrogen retention after transoperative intravenous infusion of amino acids and glucose. Design: Prospective study. Setting: Large community hospital. Patients: 18 randomly chosen patients undergoing medium or major surgeries. Interventions and Measurements: The experimental design included a 12-hour period before surgery (P1), a trans-operative period of 6 hours (P2), an early postoperative period (P3, 18 hours), and a late postoperative period (P4, 24 hours). Urinary amino acid and nitrogen were analyzed from P1 through P4. Group I, nine patients, received Ringer’s lactate solution with 5% glucose, and Group II, another nine patients, received a 6.6% amino acid and 16.6% glucose solution over a 6-hour trans-operative period (P2) starting from the anesthesia procedures. All surgical procedures lasted a maximum of 3 hours. Results: There was no statistically significant difference in urinary amino acid or adrenaline excretion between P1 and P4 in either group. Nitrogen excretion values were also similar for both groups, i.e., 0.39 ± 0.16 and 0.39 ± 0.28 g/hour, respectively. The nitrogen balance showed greater nitrogen retention (﹣0.25 ± 0.24 g/hour) in the group receiving the amino acid infusion compared to the group receiving Ringer’s lactate solution (﹣0.59 ± 0.26 g/hour) (P < 0.05). Blood plasma urea nitrogen and glycaemia did not increase at the end of the study (P4 period) in either group. Conclusion: These data indicate that trans-operative infusion of glucose and amino acids can be beneficial for patients submitted to surgical stress in terms of nitrogen retention.

Diferentes fontes de fibra em dietas a base de palma forrageira na alimentação de ovinos

O objetivo deste trabalho foi avaliar dietas a base de palma forrageira (aproximadamente 54 %) associada a diferentes fontes de fibra sobre o consumo, digestibilidade, comportamento alimentar e balanço de nitrogênio de cinco ovinos machos, com peso inicial entre 34kg. As fontes de fibra avaliadas foram: feno de tifton, casca de soja, caroço de algodão, feno de tifton + casca de soja e feno de tifton + caroço de algodão. Utilizou-se o delineamento quadrado latino 5x5. Não houve diferença para o consumo de matéria seca, matéria orgânica, proteína bruta, fibra em detergente neutro e nutrientes digestíveis totais. A palma associada ao caroço de algodão apresentou maior coeficiente de digestibilidade de extrato etéreo. Os coeficientes de digestibilidade da matéria seca e fibra em detergente neutro do tratamento com casca de soja foram superiores ao feno de tifton + caroço de algodão.O tratamentofeno de tiftonefeno de tifton+casca de sojaapresentaram maiordigestibilidade da proteína brutaem relação aocaroço dealgodão.O tratamento com palma associada à casca de soja apresentou média de excreção de nitrogênio nas fezes superior aos demais. O maior valor de excreção de nitrogênio na urina correspondeu ao tratamento feno de tifton + o caroço de algodão. A palma associada à casca de soja proporcionou menor tempo em ruminação e mastigação total. É recomendado o uso da palma forrageira associada com feno de capim tifton e casca de soja como fontes de fibra na alimentação de ovinos.

Absence of C4d urinary excretion in the early post-transplant period is associated with improved long-term kidney graft survival

IntroductionC4d urinary excretion varies according to the risk of graft rejection or progression of chronic allograft nephropathy, but its influence on long-term kidney transplant (KTx) outcomes remains unclear.The aim of the study was to determine whether the initial (1–3 months post KTx) level of C4d urinary excretion may help to predict long-term kidney allograft transplantation outcomes. Materials and methodsThe study involved 185 patients who had undergone KTx. The urinary specimens taken from the morning urine portion were assessed by ELISA test for C4d excretion. To increase the objectivity of the assessment, all measurements were divided by urinary creatinine excretion (ng/mgCr). The study population was grouped according to the C4d excretion cut-off value into low (LC4d, 109 participants) and high (HC4d, 76 participants) C4d excretion groups. Additionally a subgroup with absence of C4d in the urine (ZC4d, 26 patients) was formed. ResultsThe calculated Roc curve indicated the cut off value of the urinary C4d excretion as 12.4ng/mgCr (AUC 0.77; 95%CI 0.73–0.95). The mean C4d urinary excretions in LC4d and HC4d were 1.9±3.27 and 20.6±4.6ng/mgCr, respectively, whereas after exclusion of ZC4d subgroup, the mean C4d was 14.9±6.3ng/mgCr in the remainder. Kaplan–Meier curve analysis demonstrated a slightly higher graft survival rate (GSR) in LC4d than in HC4d group (p=0.04 by log-rank). The subsequent analysis showed the highest GSR in ZC4d subgroup (p=0.0006 by log-rank). ConclusionAlthough lower C4d urinary excretion in the early post-transplant period seems to be associated with better long-term kidney allograft transplantation outcomes, only its absence in the urine appears to be a solid predictor of improved graft survival.

Effect of povidone iodine on thyroid functions and urine iodine levels in caesarean operations

Objective: In the present study, the effects of povidone iodine (PI) used during Caesarean operations on maternal thyroid hormones and urine iodine levels in the infant and the mother were investigated.Design: Twenty-seven patients were allocated to the PI group I (Gr I), and 28 to the non-PI group (Group II). Maternal preoperative and 24th-h postoperative free T3 (fT3), freeT4 (fT4), TSH, and urine iodine levels were determined, as well as infant urine iodine values.Results: In both groups, fT3 levels before and after the operation were found to be reduced (p < 0.01, p = 0.01, respectively). However, the decrease in fT3 was approximately 1.5-fold higher in Gr I than in Gr II. TSH levels increased significantly in Gr I (p = 0.005). The urine iodine levels of the mothers increased 25% in Gr I, but only 2% in Gr II.Conclusions: The absorption of PI by the skin was found to lead to changes in fT3, TSH, and urine iodine excretion values in the mothers. The findings of this study of Caesarean operations, which have a short duration, might be a signal to be careful of thyroid hormone effects in operations lasting longer.

Faecal nitrogen excretion as an approach to estimate forage intake of wethers

Data from twenty-two digestibility trials were compiled to examine the relationship between faecal N concentration and organic matter (OM) digestibility (OMD), and between faecal N excretion and OM intake (OMI) by wethers fed tropical or temperate forages alone or with supplements. Data set was grouped by diet type as follows: only tropical grass (n=204), only temperate grass (n=160), tropical grass plus supplement (n=216), temperate grass plus supplement (n=48), tropical grass plus tropical legume (n=60) and temperate grass with ruminal infusion of tannins (n=16). Positive correlation between OMD and either total faecal N concentration (Nfc, % of OM) or metabolic faecal N concentration (Nmetfc, % of OM) was significant for most diet types. Exceptions were the diet that included a tropical legume, where both relationships were negative, and the diet that included tannin extract, where the correlation between OMD and Nfc was not significant. Pearson correlation and linear regressions between OM intake (OMI, g/day) and faecal N excretion (Nf, g/day) were significant for all diet types. When OMI was estimated from the OM faecal excretion and Nfc-based OMD values, the linear comparison between observed and estimated OMI values showed intercept different from 0 and slope different from 1. When OMI was estimated using the Nf-based linear regressions, the linear comparison between observed and estimated OMI values showed neither intercept different from 0 nor slope different from 1. Both linear comparisons showed similar R(2) values (i.e. 0.78 vs. 0.79). In conclusion, linear equations are suitable for directly estimating OM intake by wethers, fed only forage or forage plus supplements, from the amount of N excreted in faeces. The use of this approach in experiments with grazing wethers has the advantage of accounting for individual variations in diet selection and digestion processes and precludes the use of techniques to estimate forage digestibility.

Pharmacokinetic and Pharmacodynamic Properties of Single- and Multiple-Dose of Dapagliflozin, a Selective Inhibitor of SGLT2, in Healthy Chinese Subjects

BackgroundDapagliflozin, a selective, orally active, renal sodium glucose cotransporter 2 (SGLT2) 2 inhibitor, is under investigation as a treatment of type 2 diabetes mellitus (T2DM). Dapagliflozin reduces hyperglycemia by inhibiting renal glucose reabsorption and dose-dependently increasing urinary glucose excretion, independent of insulin secretion or action. ObjectivesThese studies assessed the single- and multiple-dose pharmacokinetic and pharmaco dynamic properties of dapagliflozin and its major inactive metabolite, dapagliflozin 3-O-glucuronide (D3OG), in healthy subjects residing in China. MethodsIn 2 identically designed, open-label, single- and multiple-dose studies (n = 14 for both studies), healthy Chinese subjects were administered oral dapagliflozin 5 or 10 mg. In both studies, subjects received a single dose on day 1 (single-dose administration period) followed by 6 once-daily doses on days 5 to 10 (multiple-dose administration period). Pharmacokinetic parameters (plasma and urinary dapagliflozin and D3OG), pharmacodynamic response (urinary glucose excretion), and tolerability were assessed. ResultsFourteen subjects completed the dapagliflozin 5-mg study, and 13 completed the dapagliflozin 10-mg study. Baseline characteristics were balanced across the two studies: 9 versus 10 men; mean age, 27.1 versus 28.9 years; mean weight, 62.8 versus 62.2 kg; and mean body mass index, 23.0 versus 22.2 kg/m2 in the dapagliflozin 5- and 10-mg studies, respectively. In both doses, dapagliflozin was rapidly absorbed (Tmax, ≤1.5 h), accumulation (defined as the geometric mean ratio of AUCτ at day 10 to AUCτ at day 1) after multiple dosing was minimal (<1.13 fold), and elimination half-life was 10 to 12 h. D3OG showed a slightly longer median Tmax (≤2 h) but a similar plasma concentration–time profile and half-life compared with dapagliflozin. The majority of D3OG (up to 69.7% of the dapagliflozin dose) was excreted in urine, while ≤1.9% of dapagliflozin was excreted unchanged in urine. Over a 24-hour period and at steady state (day 10), urinary glucose excretion values were 28.1 and 41.1 g with dapagliflozin 5 and 10 mg, respectively. Dapagliflozin was generally well tolerated; one dapagliflozin 10 mg–treated subject discontinued the study because of a serious adverse event (bronchitis) considered by the investigator as unrelated to dapagliflozin dosing. ConclusionsPharmacokinetic and pharmacodynamic characteristics following single- and multiple-dose dapagliflozin 5 and 10 mg oral administration in healthy Chinese subjects were as predicted from previous studies and were similar to findings observed in non-Chinese healthy subjects. Dapagliflozin dosing was well tolerated. The clinically recommended dapagliflozin dose of 10 mg once daily is expected to be appropriate in patients of Chinese ethnicity; results from an efficacy and tolerability study in Chinese patients with T2DM are awaited.

Apolipoprotein E genotype may influence urinary gammacarboxyglutamate (Gla) concentrations in young individuals

Upon degradation of vitamin K-dependent proteins (known as Gla-proteins) the free aminoacid Gla cannot be re-utilized and is excreted in the urine, where it can be used as an overall marker for vitamin K status. We report the urinary Gla excretion values in first morning void urine for healthy young Romanian subjects from birth, childhood and young adulthood. In these subjects we have evaluated age, gender and apo E genotype as potential confounders. The urinary free Gla/creat ratio (Gla/creat, mg/g) was highest in newborns (34.8 ± 19.5; p < 0.001), than fell in the group 4 to 48 months old (13.1 ± 11.1) to levels that were not significantly different from the young adult group (18.3 ± 5.5). No gender-related differences were observed in Gla/creat in newborns and young children, but Gla excretion in women was higher than in men (28.6%; p < 0.029). Remarkably, Gla excretion in subjects bearing the apo ε2+ allele was significantly lower (11.9 ± 4.2) than in those bearing combinations of the ε3+ and ε4+ alleles (20.3 ± 4.1). The novelty of this study resides in the evaluation of urinary Gla excretion in relation with apo E genotype, suggesting that apo ε2 allele is a risk factor for developing vitamin K insufficiency.

Values for evaluating the nutritional status of water-soluble vitamins in humans

Previously, we clarified that the amount of urinary excretion of water-soluble vitamins closely reflects the surplus amount of water-soluble vitamins in the body stores of rats and humans. We tried to set a tentative amount of urinary excretion of eight water-soluble vitamins of nine water-soluble vitamins (except vitamin B 12 ) for maintaining health based on experiments in healthy young females administered a semi-chemically defined diet according to Japanese Dietary Reference Intakes and related data. We proposed a tentative value for the amount of urinary excretion of water-soluble vitamins for maintaining health. The values were: 200–2000 nmol/d for vitamin B 1 ; 200–2000 nmol/d for vitamin B 2 ; 2–15 µ mol/d for 4-pyridoxic acid (a catabolite of vitamin B 6 ); 50–300 µ mol/d for the sum of the nicotinamide catabolites N 1 -methylnicotinamide, N 1 -methyl-2-pyridone-5-carboxamide, and N 1 -methyl-4-pyridone-3-carboxamide; 10–30 µ mol/d for pantothenic acid; 15–100 nmol/d for folate; 50–200 nmol/d for biotin; and 100–2000 µ mol/d for vitamin C. By using these values, we attempted to evaluate the nutritional status of water-soluble vitamins for 709 young Japanese females. The percentage within the tentative value of urinary excretion of water-soluble vitamin for maintaining health was 73.6% for vitamin B 1 , 63.5% for vitamin B 2 , 90.0% for vitamin B 6 , 85.6% for niacin, 58.1% for folate, 85.6% for pantothenic acid, 70.2% for biotin, and 65.4% for vitamin C. The percentage beyond the lower limit of detection was 22.4% for vitamin B 1 , 31.3% for vitamin B 2 , 6.2% for vitamin B 6 , 14.0% for niacin, 40.9% for folate, 12.4% for pantothenic acid, 26.2% for biotin, and 33.0% for vitamin C. The percentage over the upper limit of detection was 4.1% for vitamin B 1 , 5.2% for vitamin B 2 , 3.8% for vitamin B 6 , 0.4% for niacin, 1.0% for folate, 2.0% for pantothenic acid, 3.6% for biotin, and 1.6% for vitamin C. Nutritional assessment using urinary excretion amounts of water-soluble vitamins is persuasive, and leads to the transformation of habitual dietary intakes.

Elliott et al. Respond to "Quantifying Urine Sodium Excretion"

In their commentary (1) on our article (2), de Boer and Kestenbaum briefly summarized recent research on the relationship between salt intake (estimated from urinary sodium excretion) and cardiovascular disease (CVD). They cite a recent article by O'Donnell et al. (3) in which casual urine samples were used to characterize individual sodium intakes and an apparent J-shaped association was observed between sodium intake and CVD risk. de Boer and Kestenbaum state that “a very low intake of dietary sodium may truly increase the risk of CVD” (1, p. 1193); in contrast, an editorial (4) accompanying the article by O'Donnell et al. and subsequent publications (5–7) have highlighted methodological concerns about interpretation of the study findings. These include the use of a clinical trial population with established CVD or diabetes; high rates of medication usage among trial participants; use of a single casual urine sample to estimate individual sodium intake; inclusion of participants with sodium intakes at the bottom end of the distribution who appeared to be sicker than the rest of the study population (reverse causality); and use of data sets not specifically designed to address the sodium-CVD relationship. de Boer and Kestenbaum also cite studies purporting to show that “[d]ietary sodium restriction can lead to adverse biologic responses, including activation of the renin-angiotensin system, stimulation of the sympathetic nervous system, and unfavorable alterations to serum lipids” (1, p. 1193). These matters have been thoroughly examined as part of a systematic review undertaken by the World Health Organization to reassess guidelines on population sodium intakes (8, 9). The World Health Organization reaffirmed its previous advice that salt intake should be less than 5 g (85 mmol sodium) per day in adults and for the first time recommended a reduction in sodium intake to control blood pressure in children (8). The World Health Organization review found no evidence for adverse effects on physiological response to sodium reduction, including on the sympathetic nervous system or blood lipids (8, 9). We agree with de Boer and Kestenbaum that the International Cooperative Study on Salt, Other Factors, and Blood Pressure (INTERSALT) equations “now represent the best available method to estimate urine sodium excretion from casual urine samples” (1, p. 1194), although there are limitations. They suggest that simple transformations may improve model fit. We re-ran the equations using the natural logarithm of the urinary excretion values. This resulted in only modest improvement in model fit; the adjusted R2 increased from 0.2659 (Table 1 of our original article) to 0.2684 in men, and from 0.2327 to 0.2418 in women. We confirm that addition of urine potassium concentrations did not meaningfully improve the models; with exclusion of potassium, the adjusted R2 was reduced to 0.2636 in men and 0.2310 in women. We therefore agree with de Boer and Kestenbaum that urinary potassium can be excluded from the models and provide revised model estimates that exclude potassium in Table 1. We disagree with de Boer and Kestenbaum that inclusion of dummy variables for the 5 regions included in the models may inflate the community-level performance of the equation (1). We think it is important to include such an adjustment; by fitting a different intercept for each region, we reduce the impact of cross-region differences in levels of sodium excretion on the within-region associations of casual to 24-hour sodium excretion. Table 1. Multiple Linear Regression Analyses of Sex-Specific Individual 24-Hour Urinary Sodium Excretion in Test and Validation Data Sets Combined, International Cooperative Study on Salt, Other Factors, and Blood Pressure, 1984–1987 We restricted our analyses to Western populations in INTERSALT for which we had the most data and which are likely to be the most representative of the situation in North America and Europe. We therefore agree that the equations should be used with caution outside of these 2 settings and outside the age range for which the equations were developed (20–59 years). Finally, we agree that single urinary measures of sodium excretion are limited for assessing individual (compared with population-wide) sodium intakes. We also concur that multiple urine collections are preferable and required to increase reliability and reduce the “regression-dilution” problem for studies of individuals (10, 11).

Urinary excretion of copper, zinc and iron with and without D-penicillamine administration in relation to hepatic copper concentration in dogs

Hereditary copper-associated hepatitis in dogs resembles Wilson’s disease, a copper storage disease in humans. Values for urinary copper excretion are well established in the diagnostic protocol of Wilson’s disease, whereas in dogs these have not been evaluated. The objectives of this study were to characterize both basal and D-penicillamine induced urinary copper, zinc and iron excretion in dogs in relation to hepatic copper concentration. Beagles, Beagle-Bedlington terrier cross-breeds homozygous for the COMMD1 gene mutation that causes copper toxicosis, and Labrador retrievers with normal or increased hepatic copper concentrations were investigated. The hepatic copper phenotype was determined by histological evaluation of liver biopsies and measurement of the hepatic copper concentration by instrumental neutron activation analysis. Urinary excretion of copper, iron and zinc was measured via inductively coupled plasma optical emission spectrometry under basal conditions and after oral administration of a single dose (20mg/kg bodyweight) of the chelator D-penicillamine.There was a rapid increase in urinary excretion of copper and zinc, but not iron after D-penicillamine administration. This increase was not different between dogs with high or normal hepatic copper concentrations. D-penicillamine-induced urinary copper excretion and the copper/creatinine ratio did not correlate with hepatic copper concentrations in the dogs studied, although basal urinary copper/zinc ratios did correlate with hepatic copper concentrations in Labrador retrievers. The latter parameter may be useful in diagnostic and follow-up protocols for copper-associated hepatitis in Labrador retrievers.

Biomarkers of renal toxicity caused by exposure to arsenic in drinking water

This study is intended to explore effective and sensitive biomarkers for kidney damage after low level arsenic (As) exposure and to provide scientific evidence on cut-off values of arsenic concentrations in drinking water. The levels of α1-MG detected in urine samples were found to have statistically significant differences between high As group (As>0.05mg/L) and a combination of low and medium As exposure groups (As<0.05mg/L, p=0.018), as well as between the patient and high As groups (As in two group were both higher than 0.05mg/L, p<0.001). After the logistic regression analysis the AUC values of α1-MG between two comparisons were 0.613 and 0.701, and p value was less than 0.05. The present data demonstrate the potential value of α1-MG excretion as a biomarker of renal toxicity, which could contribute to the enforcement of the maximum limit of 0.05mg/L arsenic in drinking water for non-central water supply in rural areas.

Significance of HCG to Distinguish Parathyroid Carcinoma from Benign Disease and in Adding Prognostic Information: A Hospital Based Study from Nepal

To differentiate between benign and malignant hyperparathyroidism on the basis of excretion of HCG and its malignant isoforms in urine. This hospital based study was carried out using data retrieved from the register maintained in Manipal Teaching Hospital from 1st January, 2008 and 31st August, 2012. The variables collected were urinary HCG and HCG malignant isoform, calcium and parathyroid hormone. Preceding the study, approval was obtained from the institutional research ethical committee. Analysis was by descriptive statistics and testing of hypothesis. A p-value of <0.05 (two-tailed) was used to establish statistical significance. Out of the 20 cases, 10 were primary hyperparathyroidism and the remainder were parathyroid carcinomas. The urinary HCG 6.1∓0.6 fmol/mgCr was with in normal range in benign hyperthyroidism but was markedly elevated in three cases of malignant hyperparathyroidism (maximum value of excretion in urine for HCG was 2323 fmol/mgCr). The excretion of malignant isoform of HCG in urine was 0 in benign hyperparathyroidsm and in four cases of malignant hyperparathyroidism which fell into the category of persistantly low HCG. The maximum excretion of the malignant isoform of HCG in urine was 1.8, in the category of very high HCG. Calcium and parathyroid hormone were mildly raised in benign parathyroidism, while parathyroid hormone was markedly elevated in cases of malignant hyperparathyroidism falling into the category of very high HCG. The excretion of urinary HCG in urine has the ability to distinguish between parathyroid adenomas and carcinomas and thus has potential to become a marker of disease progression in malignant parathyroid disease.

Prediction of metabolisable energy value of broiler diets and water excretion from dietary chemical analyses

Thirty various pelleted diets were given to broilers (8/diet) for in vivo measurements of dietary metabolisable energy (ME) value and digestibilities of proteins, lipids, starch and sugars from day 27 to day 31, with ad libitum feeding and total collection of excreta. Water excretion was also measured. Amino acid formulation of diets was done on the basis of ratios to crude proteins. Mean in vivo apparent ME values corrected to zero nitrogen retention (AMEn) were always lower than the AMEn values calculated for adult cockerels using predicting equations from literature based on the chemical analyses of diets. The difference between mean in vivo AMEn values and these calculated AMEn values increased linearly with increasing amount of wheat in diets (P = 0.0001). Mean digestibilities of proteins, lipids and starch were negatively related to wheat introduction (P = 0.0001). The correlations between mean in vivo AMEn values and diet analytical parameters were the highest with fibre-related parameters, such as water-insoluble cell-walls (WICW) (r = −0.91) or Real Applied Viscosity (RAV) (r = −0.77). Thirteen multiple regression equations relating mean in vivo AMEn values to dietary analytical data were calculated, with R2 values ranging from 0.859 to 0.966 (P = 0.0001). The highest R2 values were obtained when the RAV parameter was included in independent variables. The direct regression equations obtained with available components (proteins, lipids, starch, sucrose and oligosaccharides) and the indirect regression equations obtained with WICW and ash parameters showed similar R2 values. Direct or indirect theoretical equations predicting AMEn values were established using the overall mean in vivo digestibility values. The principle of indirect equations was based on the assumption that WICW and ashes act as diluters. Addition of RAV or wheat content in variables improved the accuracy of theoretical equations. Efficiencies of theoretical equations for predicting AMEn values were almost the same as those of multiple regression equations. Water excretion was expressed either as the water content of excreta (EWC), the ratio of water excretion to feed intake (WIR) or the residual value from the regression equation relating water excretion to feed intake (RWE). The best regression predicting EWC was based on sucrose, fermentable sugars (lactose + oligosaccharides) and chloride variables, with positive coefficients. The best equations predicting WIR or RWE contained the sugar and chloride variables, with positive coefficients. Other variables appearing in these equations were AMEn or starch with negative coefficients, WICW, ‘cell-wall-retained water’, RAV or potassium with positive coefficients.

A lowered salt intake does not compromise iodine status in Cape Town, South Africa, where salt iodization is mandatory

ObjectiveUniversal salt iodization is an effective strategy to optimize population-level iodine. At the same time as salt-lowering initiatives are encouraged globally, there is concern about compromised iodine intakes. This study investigated whether salt intakes at recommended levels resulted in a suboptimal iodine status in a country where salt is the vehicle for iodine fortification. MethodsThree 24-h urine samples were collected for the assessment of urinary sodium and one sample was taken for urinary iodine concentrations (UICs) in a convenience sample of 262 adult men and women in Cape Town, South Africa. Median UIC was compared across categories of sodium excretion equivalent to salt intakes lower than 5, 5 to 9, and greater than or equal to 9 g/d. ResultsThe median UIC was 120 μg/L (interquartile range 75.3–196.3), indicating iodine sufficiency. Less one-fourth (23.2%) of subjects had urinary sodium excretion values within the desirable range (salt <5 g/d), 50.7% had high values (5–9 g/d), and 22.8% had very high values (≥9 g/d). No association between urinary iodine and mean 3 × 24-h urinary sodium concentration was found (r = 0.087, P = 0.198) and UIC status did not differ according to urinary sodium categories (P = 0.804). ConclusionIn a country with mandatory universal salt iodization, consumers with salt intakes within the recommended range (<5 g/d) are iodine replete, and median UIC does not differ across categories of salt intake. This indicates that much of the dietary salt is provided from non-iodinated sources, presumably added to processed foods.