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In children and adolescents the evaluation of proteinuria is cumbersome because of the need to obtain timed urine collections. The protein/creatinine ratio (using a Coomassie blue binding technique and a kinetic Jaffe reaction, respectively) measured in 134 pediatric patients with renal disease aged 2 months to 16 years correlated closely with the overnight urine protein excretion rates using the statistical approach suggested by Bland and Altman to compare methods of measuring some quantity. The upper limit of urinary protein/creatinine ratio measured in 252 healthy children and adolescents aged 4 to 19 years was shown to be 19 mg/mmol. No age-related differences in urinary protein excretion were noted in healthy subjects. The random urine protein/creatinine ratio provides an accurate assessment of quantitative protein excretion and avoids errors and difficulties associated with timed urine collection.

Glucocorticoid associated altered body fat distribution and muscle wasting are well known following kidney grafting. Whether an immunosuppressive regimen after glucocorticoid withdrawal (i.e. monotherapy with cyclosporine A (CsA)) is associated with normalization of altered body fat distribution and muscle mass remains to be determined. Therefore 18 renal transplant patients (nine males and nine females, 64 +/- 5 (mean +/- SEM) months since transplantation; CsA-monotherapy: 38 +/- 7 months) and 18 age, sex and body mass index matched healthy volunteers were investigated using indirect calorimetry and dual energy X-ray absorptiometry. Lean body mass (LBM) was decreased in patients mostly due to loss of striated muscle in the legs (P < 0.01). Compared to healthy controls, fat mass was increased in head and trunk (P < 0.01) and similar in extremities. Resting energy expenditure expressed per kg LBM was increased by more than 10% (P < 0.05) in patients vs. controls. Plasma insulin and glucose concentrations, total serum cholesterol (C), triglyceride levels and the ratio of LDL-C to HDL-C were all elevated (P < 0.01) in patients as compared with controls. In summary, renal transplant patients on immunosuppressive monotherapy with CsA demonstrate decreased muscle mass despite discontinuation of prednisone therapy. The increased upper body fat might account, at least in part, for peripheral hyperinsulinaemia and dyslipidaemia observed in kidney transplant patients even years after successful transplantation.

Since postmenopause unopposed oestrogen replacement therapy (ERT) increases the incidence of endometrial carcinoma, the addition of a progestin in non-hysterectomised women is mandatory for hormonal substitution. On the other hand, progestins have a negative influence on serum lipids and may thus put in question the benefits of the ERT with regard to the cardiovascular risk. Progestins lower HDL and increase LDL in a dose-dependent way according to their chemical structure. In the present non-randomised study, the influence of a cyclic combined oestrogen progestin substitution on the serum lipids has been measured. From a total of 90 apparently healthy postmenopausal patients, 59 received a transdermal ERT with 17 beta-Estradiol (Estraderm TTS 50), whereas 31 women obtained a daily dose of 0.625 mg conjugated equine oestrogens (CE) perorally. Additionally all patients were given 10 mg medroxyprogesterone-acetate (MPA) daily during the first 10 days of each month. After 6 months of therapy, the following changes of serum lipids, expressed as percentage of initial values, were measured: total cholesterol in the transdermal group -2.3% (n.s.), in the peroral group -11.8% (p < 0.00001); triglycerides -3.7% (n.s.) resp. +8.6% (n.s.); HDL cholesterol + 0.2% (n.s.) resp. -1.8% (n.s.); LDL cholesterol +1.3% (n.s.) resp. -14.8% (p < 0.00001). The calculated atherogenic indices showed a decrease in the peroral substituted group of -6.5% (n.s.) for the HDL/total cholesterol ratio and -14.8% (p < 0.002) for the LDL/HDL ratio.(ABSTRACT TRUNCATED AT 250 WORDS)

Cigarette smoking has been associated with increased upper body fat deposition, as estimated by the waist to hip ratio, which has been shown to be associated with glucose intolerance and dyslipidemia in nonsmoking subjects. Whether smoking is at the origin of central adiposity and its related metabolic disturbances is unclear. Moreover, it is controversial whether smoking influences fuel metabolism. Therefore, young healthy male volunteers smoking more than 10 cigarettes/day for more than 5 yr (n = 14) were compared with nonsmokers (n = 13) matched for age, sex, body mass index, alcohol consumption, physical activity, as well as family history for hypertension, diabetes, obesity, and coronary heart disease. After an overnight fast, blood was drawn for chemistry, body composition was assessed by dual energy x-ray absorptiometry, and fuel metabolism was determined by indirect calorimetry. Nicotine uptake was estimated by 24-h urinary excretion of cotinine. Lean and fat body mass as well as their respective segmental distribution (i.e. arms, trunk, legs, and head), total bone mineral content, resting energy expenditure, and fat, carbohydrate, and protein oxidation were similar between smokers and nonsmokers. In contrast, 24-h urinary cotinine excretion (72.0 +/- 11.4 vs. 0.8 +/- 0.2 mumol/L.24 h; P < 0.001), plasma glucose (4.62 +/- 0.09 vs. 4.25 +/- 0.1 mmol/L; P < 0.01), total cholesterol (4.87 +/- 0.15 vs. 4.27 +/- 0.16 mmol/L; P < 0.02), low density lipoprotein cholesterol (3.05 +/- 0.19 vs. 2.43 +/- 0.16 mmol/L; P < 0.02), and apolipoprotein B concentrations (1.09 +/- 0.11 vs. 0.83 +/- 0.03 mmol/L; P < 0.03) were all higher in smokers than in nonsmokers. In smokers, 24-h urinary cotinine excretion positively correlated with the waist to hip ratio (r = 0.58; P = 0.03) and negatively with hip circumference (r = 0.87; P < 0.001). Moreover, 24-h cotinine excretion positively correlated with fat oxidation (r = 0.57; P = 0.03), but was independent of the other metabolic parameters studied. These results suggest that the dyslipidemia and glucose intolerance observed in smokers are not related to either central obesity or the amount of nicotine inhaled, but, rather, are due to some other component in cigarette smoke. In contrast, in smokers, fat oxidation increases with increasing nicotine uptake, a fact that might account for the often observed weight gain after cessation of smoking, thus suggesting different mechanisms of action of tobacco consumption on cholesterol and glucose metabolism on one side and fat oxidation on the other.

For the computation of the relative supersaturation (RS) for struvite, the concentration of ammonium must be known. To estimate ammonium concentration, the use of the anion gap has been proposed1. The purpose of this study was to compare the influence of ammonium concentration and anion gap on the RS of struvite, calcium oxalate monohydrate (COM), brushite, and uric acid.

The activities of various enzymes involved in glycolysis, tricarboxylic acid cycle and fatty acid oxidation were assayed in human myometrium. A gradient of the activities from fundal to cervical myometrium was observed. In contrast to studies performed in rodents, cyclic changes of glycolytic enzymes could not be detected. Hydroxyacyl-CoA-dehydrogenase (HAD) activity was higher in secretory phase myometrium and in cases with cystic hyperplasia of the endometrium than in proliferative phase myometrium. In pregnant myometrium, lactate dehydrogenase (LDH) and glycogen phosphorylase (GLP) were increased and in postmenopausal myometrium the activities of phosphofructokinase (PFK), LDH and succinate dehydrogenase (SDH) were decreased as compared to proliferative phase myometrium. We conclude that in the human myometrium, except for HAD, activities of enzymes involved in fuel metabolism are stable throughout the menstrual cycle and that only prolonged hormonal stimulation leads to alterations of some enzyme activities.

1. Reference values for the plasma creatinine were established using the alkaline picrate method with the Greiner Selective Analyzer GSA II in relation to the Cr 51-EDTA Clearance. Individuals with normal GFR between 93 to 159 ml/min/1.73 m2 had creatinine values in men (n = 65) from 53.7 to 119.5 mumol/l (0.61 to 1.35 mg/100 ml) and in women (n = 59) from 37.7 to 107 mumol/l (0.42 to 121 mg/100 ml). 2. The creatine determinations with the GSA II were compared to those on the Technicon Analyzer, the Beckman Creatinine Analyzer, the Gemsaec-Fast Analyzer and to the enzymatic creatinine method. A good correlation (r = 0.9780-0.984) was observed. 3. With the GSA II and the enzymatic method, bilirubin showed a minor interference which was more marked with the Beckman analyzer.

1. A mercury(II)-thiocyanate method for the determination of chloride in plasma and serum was adapted for the Greiner Electronic Selective Analyzer GSA II. A sample blank value and a partial reagent blank value were determined by omitting thiocyanate from the control system. 2. The course of the reaction was investigated. For a reaction time of 350-500 s, the response was linear between 30 and 130 mmol/l. Between 90 and 110 mmol/l, the deviation between the actual and the theoretical value is less than 1%. 3. The calibration must be checked and, if necessary, restandardized; this is probably due to variable contamination of the reagents with chloride ions. 4. Haemolysis, lipaemia and bilirubin do not interfere. Protein has no effect on the course of the reaction. 5. At concentrations around 100 mmol/l, the in series precision, expressed as the variation coefficient (%), is 0.3-0.6% for aqueous solutions, 0.4-0.8% for liquid control sera, and 0.8-1.5% for lyophilized control sera. 6. No carry over was detectable from samples containing 150 to those containing 10 mmol/l.

The placenta and the fetal membranes differ in their energy dependent functions and in their blood supply. In a search for quantitative differences in the expression of enzymes involved in energy metabolism in these tissues we measured in the placenta and in amnion and chorion the activities of enzymes involved in carbohydrate metabolism (hexokinase, phosphofructokinase, lactate dehydrogenase, glycogen phosphorylase), a tricarboxylic acid cycle enzyme (succinate dehydrogenase) and an enzyme involved in fatty acid oxidation (hydroxyacyl-CoA-dehydrogenase). The activities of succinate dehydrogenase and hydroxyacyl-CoA-dehydrogenase in the placenta were higher than those in the membranes, whereas the activities of the other enzymes assayed were lower. Lactate dehydrogenase activity was higher in the amnion than in the chorion (p less than 0.01). These results could indicate that the fetal membranes depend mainly on glycolysis for an energy supply.

A simple photometric procedure was developed for the determination of thiocyanate (SCN-) in plasma and saliva without deproteinisation or dialysis. Fe(III) ions form a red coloured complex with SCN- with a maximum absorbance at 460 nm. Mercury(II) nitrate is used to run a sample blank. A manual and an automated version (COBAS BIO) of the method is described. The method is linear up to 5000 mumol/l SCN-. The CV of the between-run precision is 2.8-8% for the manual and 2.6-6.6% for the automated method. The SCN- plasma concentration was 21-134 mumol/l in nonsmokers and 44-260 mumol/l in smokers. In mixed saliva, the concentration is much higher than in plasma: 1.57-5.5 mumol/l in smokers and 0.79-3.9 mumol/l in nonsmokers. Plasma, but not oral fluid SCN-, is a valuable parameter for studying smoking habits in population surveys. However, its use is limited. In our experience only heavy smokers can be distinguished from nonsmokers.

Many, mostly congenital, hyperammonemic syndromes may occur in the first days of life. For the diagnosis of these disorders plasma ammonia levels physiologically present in neonates and early childhood should be known, preferably by the use of an enzymatic method. Full-term newborns had higher capillary ammonia concentrations on the first day of life (30–144 μmol/l) than on the fifth day (31–104 μmol/l). In the same individuals the arterial (38–89 μmol/l) are lower than the capillary concentrations (69–112 μmol/l). The venous concentrations in school children were not higher than in adults. The scatter of capillary values, however, is great. For diagnostic purposes of disorders of ammonia detoxication sampling of arterial or venous blood is preferable.

Chronic hypophosphatemia in humans is associated with a slow depletion of adenosine triphosphate (ATP) and 2,3-diphosphoglycerate (2,3-DPG) in erythrocytes, combined with shape alteration, impaired deformability, and viability of the cells. Likewise, incubation of erythrocytes in alkaline solution is associated with ATP depletion. Since in hyperventilation both hypophosphatemia and alkalosis are present, we have investigated red cell organic phosphates, shape, deformability, and osmotic fragility before, during, and after 20 min of voluntary hyperventilation. On the average, red cell ATP decreased by 42%, the blood pH increased by 0.2 units, and plasma inorganic phosphorus decreased by 46% compared with the initial values. Red cell 2,3-DPG, shape, deformability, and osmotic fragility remained unchanged. After the end of hyperventilation ATP increased rapidly to control values in parallel with the normalization of the blood pH, whereas inorganic plasma phosphorus remained at the low level observed during hyperventilation. It is concluded that the combined effects of hypophosphatemia and alkalosis in acute hyperventilation lead to an isolated fall of red cell ATP, which occurs as rapid as after total inhibition of red cell glycolysis in vitro.