Night Urine Research Articles

The effect of CYP2C19 substrate on the metabolism of melatonin in the elderly: A randomized, double blind, placebo-controlled study

The metabolism of melatonin to 6-sulphatoxymelatonin (aMT6S) and N-acetylserotonin (NAS) is catalyzed by cytochrome-P450 (CYP) isozymes CYP1A2 and CYP2C19 respectively. We studied the in vivo effect of CYP2C19 substrate (citalopram, omepratzole, or lansopratzole) on the metabolism of endogenous and exogenous melatonin by measuring the excretion of urinary aMT6S, the main metabolite of melatonin, and a reliable estimate of plasma melatonin in 15 insomniac psychogeriatric inpatients. The effect of melatonin treatment on sleep parameters was also assessed. The patients with or without CYP2C19 substrate were treated for 21 days randomly in a double-blind manner with placebo or 2 mg exogenous melatonin orally. aMT6S excretions were measured radioimmunologically from night urine at baseline (day 0), on day 21, and one day after the treatment was discontinued (day 22). Sleep parameters were assessed using the Sleep Assessment Scale and the Sleep Quality Scale. In the control patients receiving only melatonin, aMT6S excretion increased 72-fold and returned to baseline on day 22. In the patients receiving melatonin + CYP2C19 substrate, aMT6S excretion increased 156-fold and was, on day 22, still 6.4-fold higher than at baseline (p = 0.04). The 22/0 day aMT6S excretion ratio was 10-fold higher in the patients treated with melatonin + CYP2C19 substrate when compared with that in the subjects treated with placebo + CYP2C19 substrate (p = 0.02). CYP2C19 substrate did not affect the metabolism of endogenous melatonin. The sleep parameters in the patients on melatonin treatment did not differ from those in the patients treated with placebo. In conclusion, it may be inferred that CYP2C19 substrate slows the metabolism of exogenous melatonin and increases its bioavailability, as shown by the augmented excretion of aMT6S, probably by inhibiting the conversion of melatonin to NAS via CYP2C19 isozyme. Melatonin therapy may not affect the sleep parameters in our psychogeriatric inpatients.

Urinary nitrite excretion and urinary variables in patients with primary nocturnal frequency of micturition: effects of indomethacin suppositories

Urinary nitrite excretion was measured in patients with primary nocturnal frequency of micturition (PNFM) and in normal individuals. Effects of indomethacin suppository on urine volume and other urinary variables were evaluated. The study comprised seven patients with PNFM and seven healthy control (age range 30-45 years). Nitrite was assayed in spot morning urine samples; urine volume, urine osmolality and electrolytes, serum osmolality and electrolytes and functional bladder capacity (FBC) were assayed. Both groups were then given 100 mg of indomethacin suppository daily for a maximum of 10 days and urinary variables were re-evaluated during day 10. Results showed that urinary nitrite excretion of patients with PNFM was greater than that of the normal subjects (230+/-62 umol/l vs. 42+/-30 umol/l, P<0.05). The mean (SD) 24 h urine volume and osmolality, the night urine volume and osmolality, serum osmolality, FBC, creatinine clearance, fractional excretion of sodium (FENa), fractional excretion of potassium (FEK), and urinary excretion of glucose and potassium were lower in patients with PNFM as compared with normal individuals, although not statistically significantly so, except for FBC that was significantly lower in the patients. Urinary excretion of sodium, calcium, chloride, phosphorus, magnesium, day-night urinary volume ratio, spot morning osmolality, nocturnal index, and nocturnal polyuria index were higher in patients with PNFM. Indomethacin decreased the 24 h urinary volume by 21%, creatinine clearance by 12%, osmolar clearance by 14% and urinary protein excretion by 38% in the patients. These variables decreased by 26, 45, 17 and 12% respectively in the healthy subjects, whereas 24 h urinary protein excretion increased mildly by 9%. Indomethacin increased day-night urinary volume ratio by 73% in the healthy subjects. It might be concluded that urinary nitrite excretion, urinary excretion of sodium, chloride, phosphorus, calcium, and magnesium increased and FBC decreased in patients with PNFM; Indomethacin decreased urinary volume, FENa, FEK, osmolar clearance, and free water clearance in the healthy subjects and the patients. These might explain the mechanism of action of indomethacin to reduce frequency of voiding. The possible interaction of prostaglandin and NO in the pathogenesis of PNFM is discussed.

Effectiveness of an anti‐inflammatory drug, loxoprofen, for patients with nocturia

There is increasing evidence that non-steroidal anti-inflammatory drugs are effective for the treatment of nocturia. In this study, we attempted to investigate the role of loxoprofen sodium (loxoprofen) in the therapeutic management of patients with nocturia. Fifteen benign protastatic hyperplasia and/or overactive bladder patients (13 males and 2 females, 71.1 +/- 1.5 years old) with three or more voids per night were involved. These patients had received standard drug therapy. Although these patients had received standard drug therapy for more than half a year, they had still three or more episodes of nocturia. The patients took a single dose of 60 mg of loxoprofen at night prior to sleep. Before and 1 week after the initiation of this therapy, the effects of this treatment were assessed by frequency volume chart and a questionnaire. In the questionnaire, seven patients answered as excellent, six patients demonstrated improvement of their symptoms, two patients did not show a significant change in their symptoms and no patients demonstrated a deterioration in the symptoms. In frequency volume chart, total void per day, total void per night, total urine volume per day, total night urine volume per day and single voided volume in the night before and after this treatment were 9.97 +/- 0.81 and 8.99 +/- 0.74 per day, 3.82 +/- 0.25 and 1.82 +/- 0.27 per night, 1349 +/- 81 and 1258 +/- 91 mL per day, 567 +/- 46 and 325 +/- 51 mL per night, and 143 +/- 13 and 149 +/- 10 mL, respectively. Loxoprofen can be effective and useful for patients with nocturia. Our data suggest that the main mechanism of this effect is to decrease urine production during a night's sleep.

Exposure to Environmental Tobacco Smoke and Urinary 1-Hydroxypyrene Levels in Preschool Children

Environmental tobacco smoke (ETS) contains relatively high concentrations of polycyclic aromatic hydrocarbons (PAHs). Urinary 1-hydroxypyrene (1-OHP), a metabolite of pyrene, is a good indicator of PAH exposure in occupational studies. In this study, we investigated the relationship between urinary 1-OHP concentration and ETS exposure in preschool children. Forty preschool children, aged 24-76 months, were studied during November and December, 1999. Two spot-urine specimens (one in the morning immediately after the subject woke up and the other at night before the subject went to bed) were collected 1 day after completion of a questionnaire, in order to determine 1-OHP concentrations by fluorescent spectrophotometry. Overall, urinary 1-OHP concentrations were relatively low but detectable (morning: median, 0.021 microg/g creatinine; range, 0.002-1.019 microg/g creatinine; night: median, 0.015 microg/g creatinine; range, 0.002-1.328 microg/g creatinine). Multiple linear regression analyses revealed that the total number of cigarettes smoked by the children's fathers during the 3 days prior to collection of the urine specimens was significantly associated with their urinary 1-OHP concentrations, after adjusting for other confounders. Each cigarette smoked by a child's father resulted in an average 9.6% increase in 1-OHP concentration in the morning urine specimen (95% confidence interval = 1.8-18.1%; p = 0.02). We did not find a significant increase in the 1-OHP concentration in night urine specimens (p = 0.19). Although the sample size was small, these findings indicate that urinary 1-OHP may be a suitable biomarker of ETS carcinogen exposure in children.

The influence of causal attribution of parents on developing the child enuresis

Causal attributions are affirmed as a cognitive element able to explain emotional and motivational aspects of behaviour of some categories of adult psychiatric patients, primarily depressive ones. Theoretical and practical success of cognitive ideas in explaining the origination of depressive disorders, and in the monitoring of depressive patient treatment has led to further development of theory, but also to the attempt to apply the learning about causal attributions to various problems. Characteristic attempts are those that the problems of child abuse, children?s depression, upbringing problems, school failure, hyperactivity, enuresis, and long-term effects of different child treatment, too, are analysed from the point of view of causal attributions. By assessing parent causal attributions regarding child night urination, we wanted to establish to what extent specific attributions for child behaviour differentiate the parents of children having this problem from those parents whose children have established control. Parents were assessed in terms of four dimensions of causal attributions for child?s problem. Those are the dimensions of globality, counter-lability, internality, and the stability of the cause of child?s problem. The analysis of parent causal attributions show that mothers and fathers in both assessed groups similarly experience the cause of enuretic problems of their children. Enuresis is seen as caused by specific, internal, and instable causes. Such a system of dimensions could correspond to the belief that the main etiological factor of the enuresis is maturing. For more reliable verification of this attitude, longitudinal strategy in research is necessary, especially to comprehend whether parental attributions have been developed as an effect of persistent enuresis, or whether the enuresis is developed as an effect of parental attributions.

Violence Exposure, Catecholamine Excretion, and Blood Pressure Nondipping Status in African American Male Versus Female Adolescents

Objective Nondipping status (<10% decrease in blood pressure [BP] from awake to asleep) has been associated with end-organ disease (stroke and left ventricular hypertrophy) in adults. Nondipping status has also been observed in 30% of healthy African American adolescents, but little is known about the correlates of nondipping status in adolescents. This study examined the relationship between violence exposure, catecholamine excretion, and BP nondipping status in 56 healthy African American adolescents (27 boys, 29 girls; ages 11–18 years). Methods Participants completed the Survey of Exposure to Community Violence, wore an ambulatory BP monitor and provided one timed day and night urine collection for determination of epinephrine and norepinephrine excretion. Results Boys had higher daytime epinephrine (5.1 ± 3.3 vs. 2.6 ± 2.3 ng/min, p < .001) and norepinephrine excretion (29.2 ± 25.1 vs. 16.5 ± 14.9 ng/min, p < .05) and showed a greater prevalence of mean BP nondipping status than girls (37% vs. 10%, p < .03). Mean BP nondipping status was positively associated with victimization (r = 0.42, p < .0001). Regression analyses indicated a significant interaction between hearing about violence and sex for predicting daytime epinephrine (p < .02), with male nondippers showing a stronger positive association (partial correlation = 0.59, p < .05) than females (partial correlation = 0.03, p = NS). Logistic regressions also demonstrated a significant interaction between hearing about violence and sex for predicting mean BP dipping status, with male nondippers reporting the greatest exposure. Conclusions Mean BP nondipping was associated with victimization in both boys and girls. Boys who reported higher levels of hearing about violence showed greater daytime epinephrine excretion and were more likely to be classified as nondippers.

Impact of hormone replacement therapy on endogenous estradiol metabolism in postmenopausal women

Objectives: Changes in estradiol metabolism may play a role in the pathophysiology of different diseases, of special interest being an increase in D-ring over A-ring metabolites for the risk of breast cancer. In the present work we investigated the effect of exogenous estradiol therapy on endogenous estradiol metabolism in postmenopausal women. Methods: Three different studies were carried out in 126 women: in study A the women were treated for 4 weeks either with oral or with transdermal 17β-estradiol, in study B for 4 weeks with oral or transdermal 17β-estradiol sequentially combined with oral or transdermal norethisterone acetate, and in study C for 12 weeks either with oral 17β-estradiol or with an oral continuous combination of 17β-estradiol with the new progestin dienogest. As main representatives of the A- and D-ring metabolism, 2-hydroxyestrone (2-OHE1) and 16α-hydroxyestrone (16-OHE1), respectively, were measured in 8 h night urine using enzyme immunoassay technique. Results: Oral estradiol treatment resulted in a significant higher excretion of estradiol metabolites compared to transdermal treatment. Neither oral nor transdermal estradiol induced a significant change in the ratio of 16-OHE1 to 2-OHE1. The addition of oral or transdermal norethisterone acetate to estradiol did not alter on average the endogenous estradiol metabolism, although in individual patients a significant increase in 16-OHE1 metabolism was observed only with oral norethisterone. The continuous oral addition of dienogest did not lead to any significant change in estradiol metabolism. Conclusions: These results indicate that oral estradiol replacement therapy enhances the quantity of circulating estradiol metabolites. This may have a more negative impact on estrogenic target cells as compared to transdermal application. Progestin addition to estradiol replacement therapy seems to have no major impact on endogenous estradiol metabolism. Further studies, however, are necessary to evaluate the progestin effect in possible pre-disposed patients.

Cystine analyses of separate day and night urine as a basis for the management of patients with homozygous cystinuria.

Based on previous observations of the diurnal variation of urinary cystine excretion, the use of separate day and night urine collections was proposed. To improve the medical treatment of patients with cystinuria, this strategy was performed to guide the fluid intake and the administration of SH compounds (tiopronin, D-penicillamine, and MESNA).Twenty-six patients (19 treated with SH compounds and seven with alkalinization and hydration only) were followed during two 3.5-year periods. During Period 1, 24-h urine was collected and during Period 2, separate day and night urine was collected. There were 56 episodes of high urinary cystine supersaturation (> 1,200 micromol/l) during Period 2, 47% of which would have evaded detection with 24-h urine analysis. In comparison with Period 1, the urinary cystine concentration was lower (P < 0.05), and the urinary volume was higher (P < 0.05) during Period 2. Patients treated with tiopronin had reduced cystine excretion (P < 0.05) and at the end of Period 2, an increased dose of tiopronin, reflecting a more aggressive treatment. Furthermore, a reduced number of stone episodes and need of active stone removal (P < 0.05) was noted in the whole group of patients. Analyses of separate day and night urine samples can be used advantageously to reveal episodes of high supersaturation with cystine not detected in 24-h urine samples. Such a procedure might be useful for optimizing the treatment of patients with cystinuria.

Crystallisation properties in stone forming and normal subjects' urine diluted using a standardised procedure to match the composition of urine in the distal part of the distal tubule and the middle part of the collecting duct.

Using a standardised procedure, we assessed the crystallisation properties of calcium phosphate in urine with a composition matching that in the distal part of the distal tubules (DTd) and of calcium oxalate in urine with a composition matching that in the mid-collecting duct (CDm). We used 8-h urine samples collected between 2200 h and 0600 h with sodium azide as preservative. Urine from ten patients with recurrent CaOx stone formation and from ten normal subjects was used for the measurements. The DTd and CDm samples were obtained by diluting the voided 8-h urine to 3000 ml and 1750 ml per 1.73 m2 body surface area, respectively. The nucleation was studied in DTd urine following supersaturation with CaP. The crystal size distribution was assessed with a Coulter counter both following supersaturation of DTd urine with CaP and of CDm urine with CaOx. The crystallisation of CaP in DTd urine as well as that of CaOx in CDm urine, in the presence of CaP crystals that had been precipitated in DTd urine, was measured with the isotope technique. The inhibition of CaOx and brushite crystal aggregation in standardised diluted aliquots of DTd and CDm urine was assessed spectrophotometrically as the rate of sedimentation. There was a slightly increased sedimentation rate and a lower initial absorbance in DTd urine from stone formers supersaturated with CaP. Although these findings might reflect a state of increased crystal aggregation in stone formers' urine, this could not be confirmed by crystal size measurements in the Coulter counter. The inhibition of brushite crystal aggregation in DTd urine was significantly in stone formers' urine than in normal subjects' urine (P < 0.001). Moreover, all inhibition values in DTd samples from stone formers were negative, suggesting a promoter effect on crystal aggregation. The inhibition of CaOx crystal aggregation in CDm urine also was significantly higher in CDm urine from normal subjects than in CDm urine from stone formers (P < 0.05). For all other variables the level was similar when urine samples from the two groups were compared. Although this series of crystallisation assessments was carried out on a small number of standardised diluted urine samples only, the results nevertheless emphasise a defect in aggregation inhibition as one important determinant for an abnormal calcium salt crystallisation in patients with recurrent stone formations. This difference obviously includes aggregation of both CaP crystals in DTd urine and CaOx crystals in CDm urine. The results also show that assessment of crystallisation properties of this kind can be carried out in standardised, diluted 8-h night urine samples, which accordingly can be used in the routine work-up of patients with calcium stone disease. Such an approach might prove useful in order to get information on the combined effects of the driving force of supersaturation and crystallisation modifying properties accomplished by urinary macromolecules and other modifying agents.

Urinary aquaporin 2 and calciuria correlate with the severity of enuresis in children.

This study examined the hypothesis that nocturnal enuresis might be paralleled by aquaporin 2 (AQP2) urinary excretion. Eighty children who experienced nocturnal enuresis were studied and compared with 9 healthy children. The 24-h urine samples were divided into two portions: night collections and day collections. Creatinine equivalents of urine samples from each patient were analyzed by Western blotting. AQP2 levels were semiquantified by densitometric scanning and reported as a ratio between the intensity of the signal in the day urine sample versus the night urine sample (D/N AQP2 ratio). The D/N AQP2 ratio was 0.59 +/- 0.11 (n = 9) in healthy children and increased to 1.27 +/- 0.24 (n = 10) in a subpopulation of enuretic children who had low nocturnal vasopressin levels. In enuretic children who displayed hypercalciuria and had normal vasopressin levels, the D/N AQP2 ratio was 1.05 +/- 0.27 (n = 8). These data indicate that reduced secretion of vasopressin and absorptive hypercalciuria are independently associated with an approximately twofold increase in the urinary D/N AQP2 ratio. When low nocturnal vasopressin levels were associated with hypercalciuria, a nearly threefold increase in the D/N AQP2 ratio was observed (1. 67 +/- 0.41, n = 11). In addition, in all enuretic patients tested, the urinary D/N AQP2 ratio correlates perfectly with the severity of the disorder (nocturnal polyuria). The findings reported in this article indicate that urinary AQP2 correlates with the severity of enuresis in children.

Repeated Urine Analysis in Patients with Calcium Stone Disease

Objective: To study the variability in urine composition with respect to factors of importance for the calcium salt crystallization process and to test the reliability of using one or several urine samples in the clinical evaluation. Patients and Methods: Twelve patients collected 16-hour daytime and 8-hour night urine samples during 4 days of the same week. The urine was analysed for calcium, oxalate, phosphate, magnesium, citrate and pH, and the ion activity products of CaOx [AP(CaOx) index] and CaP were calculated. The risk of CaOx crystallization, as well as the inhibition of CaOx crystal growth and aggregation, were assessed. Results: There was a good correlation between estimates of the AP(CaOx) index in the different samples, as well as between the AP(CaOx) index and the direct assessment of the risk of CaOx crystallization in the night and daytime urine samples. There was, however, a pronounced intra-individual variation of all variables and parameters. With the assumption that an abnormality would appear in at least one of the four samples, we found that in more than 80% of the cases, two 24-hour (16 + 8 h) urine samples were sufficient to establish whether the patient had a normal or an abnormal urine composition. Conclusion: Urine samples collected during two 24-, 16- or 8-hour periods appear to be useful for detecting biochemical abnormalities considered of importance for CaOx stone formation.

Evaluation of urine composition and calcium salt crystallization properties in standardized volume-adjusted 12-h night urine from normal subjects and calcium oxalate stone formers.

The volume of 12-h night urine from ten normal men (NM), ten normal women (NW) and 31 male calcium stone formers (SFM) was adjusted to 750 ml and analysed with respect to supersaturation with calcium oxalate (CaOx) and calcium phosphate (CaP), inhibition of CaOx crystal growth and aggregation, as well as the CaOx and CaP crystallization propensity. Concentrations of oxalate and glycosaminoglycans and AP(CaOx) index, an estimate of the CaOx ion-activity product, were higher and the concentration of citrate lower in NM than in NW. In SFM the directly assessed risk of CaOx crystallization was higher and the inhibition of CaOx crystal growth lower than in NM. There were no differences between the groups regarding inhibition of CaOx crystal growth by 74% dialysed urine or inhibition of CaOx crystal aggregation. SFM with mixed CaOxCaP stones had a higher concentration of phosphate and a higher AP(CaP) index at pH 7.0 than SFM with CaOx stones.

A single measurement of biochemical markers of bone turnover has limited utility in the individual person

Biochemical markers of bone turnover are used to estimate the rate of bone loss in the individual osteoporotic patient. During recent years it has become increasingly clear that the biological variability of biochemical bone markers has to be taken into consideration in the evaluation of their usefulness in the clinical setting. Eleven premenopausal, 8 perimenopausal and 11 postmenopausal healthy women were included. We assessed the analytical and the biological components of variation for a number of resorptive and formative bone markers: u-hydroxyproline, u-pyridinoline, and u-deoxypyridinoline together with u-calcium and u-creatinine, s-total alkaline phosphatases and s-osteocalcin. Blood and urine samples were collected five times with 7-day intervals. Urinary parameters were expressed as outputs and corrected for creatinine in fasting night urines and second void fasting morning urines. The absolute values differed with a tendency towards increasing values in the postmenopausal women, but the biological variations in relation to menopausal status were not different. The biological variability was much higher for the urinary resorptive markers than for the formative markers in the blood. The critical difference expressing the difference needed between two serial results from the same person to be significant at a 5% level was 15% for s-alkaline phosphatases. 18% for s-osteocalcin, and lowest in the second void fasting morning urines with values of 28% and 34% for u-pyridinoline/creatinine and u-deoxypyridinoline/creatinine, and 50% and 112% for u-hydroxyproline/creatinine and u-calcium/creatinine, respectively. The index of individuality, denoting the individual variation divided by the variation between subjects, was in the range from 0.19 for s-alkaline phosphatases to 1.23 for u-hydroxyproline/minute in second void fasting morning urine making the use of conventional reference intervals difficult. Low indices, however, indicate high test performance and offer the possibility of stratification of persons within a range. The number of samples required to determine the true individual mean value $5% for the single person, ranged from 5 for s-total alkaline phosphatases, 6 for s-osteocalcin, 23 for u-deoxypyridinoline/creatinine in the fasting morning urine to over two hundred for u-calcium analytes. It is concluded that, due to high biological variation, a single measurement of biochemical markers of bone turnover is of limited utility in the individual person. We recommend that routine clinical use of biochemical markers should be restricted until further evidence justifies it.

Clinical evaluation of monotherapy with cefpirome for infections complicating hematological disorders

The clinical effects of cefpirome (CPR) monotherapy were evaluated in 38 infected patients with hematological diseases. The underlying diseases of the patients were chiefly acute leukemia, myelodysplastic syndrome, malignant lymphoma, and aplastic anemia, and 18 patients were clinically neutropenic (<500 neutrophils/μL). Septicemia, pneumonia, or an unexplained fever, were the predominant complicating infections. The clinical efficacy of CPR was satisfactory or improved in 89.5% of patients. When compared to empirical combination therapy with 2 antibiotics, monotherapy with CPR reduced the drip infusion volume and the frequency of antibiotic administration, resulting in a better quality of life due to less frequent night urination, a low cost/benefit ratio, and reduction in nursing responsibilities. Due to this high efficacy rate, monotherapy with CPR should be considered as a front-line therapeutic approach in patients with infections accompanying hematological diseases, particularly those with neutropenia. J Infect Chemother 1996;2:75-78.

Diurnal variations and 24 hr. urinary excretion of mucoprotein and Tamm-Horsfall protein in renal stone patients

Six consecutive day and night urine samples from 25 renal stone patients and 25 comparabe controls were collected and analysed for total mucoproteins, Tamm-Horsfall mucoprotein, & creatinine. In normal subjects the 24 hour, day and night urinary excretion of mucoprotein was 101.4±34.5, 58.2±20.1 and 40.5±19.3 mg respectively. The Tamm-Horsfall mucoprotein excretion was 43.9±18.4, 21.5±8.6 and 20.6±9.9 mg in respective samples. Stone formers excreted significantly higher amount of mucoprotein but not the Tamm-Horsfall mucoprotein. Furthermore, the diurnal variations was visible only for in case of total mucoprotein in both the groups.

Clinical usefulness of urinary growth hormone measurements in normal and short children according to different expressions of urinary growth hormone data.

To assess the clinical usefulness of urinary growth hormone (UGH) measurements, a UGH determination technique, including dialysis, ultrafiltration, and measurement by polyclonal-coated tube RIA, was established. Sixty-three short children were studied: 56 idiopathic growth retarded (37 prepubertal and 19 pubertal) and seven prepubertal with classic GH (growth hormone) deficiency. Forty-two healthy children (32 prepubertal and 10 pubertal) served as controls. Two groups of adults were studied: eight with active acromegaly and 11 healthy controls. UGH was measured in 24-h urine samples from all patients and controls. Mean +/- SD UGH excretion expressed as ng/24 h was significantly lower in the GH-deficient group compared with prepubertal growth-retarded and control children (p less than 0.01). No differences were found between UGH excreted by controls and by the growth-retarded groups. Pubertal children excreted significantly higher amounts of GH when UGH was expressed as ng/24 h (p less than 0.02 and p less than 0.03, respectively), but this difference disappeared when UGH was expressed as ng/g creatinine. UGH was significantly higher in acromegalic patients compared with adult controls (p less than 0.001). Differences between day, night, and 24-h UGH were studied in 23 children. UGH in night urine was significantly lower whether expressed as the total amount or as ng/g creatinine. The effect of recombinant hGH administration on UGH was studied in 13 children after 6 and 12 mo of treatment. UGH increased significantly under recombinant hGH treatment.(ABSTRACT TRUNCATED AT 250 WORDS)

Desmopressin reduces night urine volume in geriatric patients: implication for treatment of the nocturnal incontinence.

Desmopressin reduces night urine volume in geriatric patients: implication for treatment of the nocturnal incontinence.

The excretion of 17-ketosteroids and 17-hydroxycorticosteroids in night urine of elite rowers during altitude training.

During an altitude training camp (23 days, 1850 m above sea level) we collected night urine from 36 German elite rowers in order to measure the excretion of urea, creatinine, 17-ketosteroids (17-KS), and 17-hydroxycorticosteroids (17-OHCS). 17-KS and 17-OHCS represent the major metabolites from endogenous anabolic and catabolic steroid hormone systems. There was no significant change in the excretion of 17-OHCS during the training camp (mean value: females 0.0025 +/- 0.0011, males 0.0033 +/- 0.0012 mg/kgbw.h). Significant increases in the excretion of 17-KS (mean value: females 0.007 +/- 0.003, males 0.0092 +/- 0.0039 mg/kgbw.h) and in the ratio 17-KS/17-OHCS (mean value: females 3.13 +/- 1.65, males 3.11 +/- 1.71) were found during the first week and towards the end of the training camp. To investigate training effects on the excretion of these hormone metabolites, we used a recently described classification for rowing training (categories I to IV of rowing-specific training according to lactate levels and non-rowing specific categories) and a corresponding rowing data base. More than 80% of training was performed at a lactate level lower than 2 mmol/l. Using multiple regression analysis, the general finding was that in males the ratio of 17-KS/17-OHCS increased with rowing specific and non specific training regimes where a lactate level below 2 mmol/l was observed. Training at higher lactate levels caused a decrease in the ratio that may be interpreted as a shift in the production from endogenous androgenic steroid hormones to cortisol. No significant effects of single training variables were found in female rowers, which indicates major training influences on testosterone metabolism. The influence of further factors such as a relationship between urine urea and 17-KS in males are described and need further explanation.

A new assay for β-thromboglobulin in urine

Measurements of β-thromboglobulin (βTG) excretion in urine may be of value for “field” studies and due to problems with sampling artifacts for BTG in plasma. Previous studies have used a radioimmunoassay designed for plasma without characterizing the “BTG” immunoreactivity in urine. We describe modifications of the assay which increase its sensitivity and a sample work-up procedure using Sephadex G-25M columns separating high molecular weight (HMW) components (presumably intact βTG) from low molecular weight (LMW) immunoreactivity (i.e. βTG fragments and/or non-specific interferences). The sensitivity of the assay (with 2.5 ml sample) is <12 pg/ml HMW BTG. Inter-and intraassay coefficients of variation were 7–10%. Only 33 (range 5–75)% of BTG immunoreactivity in urine represented HMW βTG. LMW immunoreactivity may be related to salt and other non-specific influences in the sample. Recoveries of βTG were quite variable (9–100%) in unextracted urines, but high and reproducible (80±2%) in the HMW fraction. Thus, nonspecific interferences with BTG measurements in certain urines are overcome by the separation step. Using Sephadex fractionation βTG immunoreactivities in night urines (n=15) were: 20±3 pg/ml in the HMW fraction, 70±8 pg/ml in the LMW fraction, and 85± 10 pg/ml by direct assay. HMW βTG increased in daytime samples (to 30±5 pg/ml; p<0.01), but no diurnal variation was seen in the LMW fraction or with the direct assay. Thus, selective analysis of HMW βTG in urine circumvents problems with nonspecific immunoreactivity and apparent interferences with measurements of intact βTG. The present more selective assay for HMW immunoreactivity increases the possibility of detecting physiological changes in βTG release in vivo by urinary measurements.

Measurement of organic halogen compounds in urine as an indicator of exposure.

The report describes the measurement of urinary organic halogen compounds. The method is an application of the adsorbable organic halogen assay which is widely used for the analysis of industrial waste water and drinking water. It was found that this assay can be applied to human urine if the urine is pretreated to hydrolyze the mucins so as to cleave the neuraminic acid residues responsible for the high viscosity of these slimy proteins. The method was found to be sensitive down to 1 microgram of organic halogen/100 ml of urine. Fifty to 260 micrograms of organic halogen was measured in the night urine of healthy, occupationally unexposed volunteers. Since many toxic chemicals to which man may be exposed environmentally or occupationally are, in fact, halogen compounds, this assay may be used to monitor for human exposure.