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P Jaeger

Publications and source records attributed to P Jaeger.

At least 55 records · Page 3Linked to original sources
PubMed1996

Effect of calcium-channel blockers on calcium-phosphate metabolism in patients with end-stage renal disease.

BACKGROUND: After EDTA-induced hypocalcaemia, healthy volunteers treated with diltiazem display more severe hyperparathyroidism than subjects on felodipine studied under identical conditions. Therefore patients with end-stage renal disease (ESRD) and severe secondary hyperparathyroidism might be particularly sensitive to this side-effect. METHODS: To test this hypothesis, seven patients with ESRD on chronic haemodialysis (3 women and 4 men) with serum levels of intact PTH ranging from 204 to 675 pg/ml were studied both before and during the first 180 min of haemodialysis against a dialysate with low calcium concentration (0.75 mmol/l, n = 6 and 1 mmol/l, n = 1) under the following three experimental conditions: control, felodipine (10 mg/day) and diltiazem (120 mg b.i.d.). RESULTS: At onset of dialysis, plasma phosphorus level was higher on diltiazem (2.03 +/- 0.08 mM) than on felodipine (1.64 +/- 0.10, P < 0.02), and on the latter it was lower than in control condition (1.88 +/- 0.16, P < 0.02). As a probable consequence, blood ionized calcium concentration was lower on diltiazem (1.14 mM +/- 0.02, mean +/- SEM) than on felodipine (1.2 +/- 0.03, P < 0.05) or in control condition (1.17 +/- 0.01, NS). There was a trend for intact PTH to be higher on diltiazem (324 +/- 47 pg/ml) than on felodipine (246 +/- 55) or in control condition (305 +/- 49) and 1,25-dihydroxyvitamin D was higher indeed on diltiazem (6.70 +/- 0.92 pg/ml) than on felodipine (4.75 +/- 0.91, P < 0.02) or control (3.87 +/- 0.62, P < 0.05). Area under the curve PTH over the first 60 min of dialysis was higher by 16 +/- 7% on diltiazem than on felodipine (P < 0.05). CONCLUSIONS: While on diltiazem rather than on felodipine, patients with ESRD display higher plasma phosphorus levels, and slightly aggravate the degree of severity of hyperparathyroidism recorded during haemodialysis against low-calcium dialysate. The long-term effect of this new observation remains to be evaluated.

Aged↗
PubMed1996

Six-month overnight administration of intraperitoneal amino acids does not improve lean mass.

UNLABELLED: Intraperitoneal administration of 1% amino acid dialysis solution in patients on continuous peritoneal dialysis (CAPD) is associated with improvement in plasma amino acid concentrations and inconsistent results with respect to nitrogen balance. Whether alteration(s) in lean mass and body fat distribution also occur remains controversial. Therefore 18 patients (P), on CAPD for at least 6 months, were assigned in a prospective and controlled fashion to receive overnight either a 1% amino acid (AA-P) or a 1.36% glucose (Glu-P) containing dialysis solution. Body composition was investigated using whole body dual energy X-ray absorptiometry (Hologic QDR 1000/W). In P receiving glucose (n = 9), total body fat mass increased (+1.0 +/- 0.4 kg, mean +/- SEM, p < 0.03), whereas in patients on amino acids (n = 9), it decreased (-0.6 +/- 0.3, p < 0.02). This decrease in fat mass in AA-P was attributable to a decrease in upper body fat (-0.6 +/- 0.2, p < 0.02), whereas in Glu-P, it increased (+0.9 +/- 0.03, p < 0.03). No change in lower body fat was observed in either group. Total body lean mass remained similar in both groups during the six months of study (AA-P: 46.6 +/- 2.9 kg vs 47.0 +/- 3.0 kg, Glu-P 50.8 +/- 3.2 vs 50.1 +/- 2.2 kg baseline vs 6 months, respectively). In AA-P plasma urea concentrations increased from 25 +/- 2 to 34 +/- 3 mmol/l (p < 0.05), whereas plasma bicarbonate concentrations were similar before and after 6 months of therapy in either group. Plasma albumin and transferrin concentrations did not change in either group. Protein catabolic rate increased in AA-P (p < 0.01), whereas K x t/V did not change as a consequence of either therapy. CONCLUSION: Reduction in the amount of glucose in the peritoneal dialysate and the addition of amino acids decreases, whereas continuous dialysis with overnight glucose increases upper body fat over a 6-month period. However, no changes in protein stores were observed with the addition of amino acids. Therefore overnight peritoneal dialysis with amino acids offers minor advantages to protein-malnourished patients on CAPD, but may be of benefit in overweight CAPD patients.

Absorptiometry, Photon↗
PubMed1996

Effect of disodium monofluorophosphate, calcium and vitamin D supplementation on bone mineral density in patients chronically treated with glucocorticosteroids: a prospective, randomized, double-blind study.

To study the effect of fluoride on bone mineral density (BMD) in patients treated chronically with glucocorticosteroids, 15 subjects (renal grafted, n = 12; skin disease, n = 1; broncho pulmonary disorder, n = 1; Crohn's disease, n = 1) were prospectively studied in a double-blinded manner and randomly allocated either to group 1 (n = 8) receiving 13.2 mg/day fluoride given as disodium monofluorophosphate (MFP) supplemented with calcium (1,000 mg/day) and 25-hydroxyvitamin D (calcifediol) (50 micrograms/day), or to group 2 (n = 7) receiving Cas+ calcifediol alone. An additional group of 14 renal transplant patients treated chronically with glucocorticosteroids but exempt of specific therapeutic intervention for bone disease was set up as historical controls. BMD was measured by dual-energy X-ray absorptiometry (DXA, Hologic QDR 1000) performed at months 0, 6 and 12 for groups 1 and 2 (lumbar spine, total upper femur, diaphysis and epiphysis of distal tibia), or 11-31 months apart with calculation of linear yearly changes for the historical cohort. Lumbar BMD tended to rise in groups 1 and 2, and to fall in group 3, the change reaching statistical significance (p < 0.05) in group 1, thus leading to a significant difference between groups 1 and 3 (p < 0.05). At upper femur, tibial diaphysis and tibial epiphysis, no significant change in BMD occurred in any of the groups. In conclusion, lumbar BMD rises more after a mild dosis of fluoride given as MFP and combined to calcium and calcifediol than on Ca+ calcifediol alone, without changes in BMD at the upper femur or distal tibia.

Absorptiometry, Photon↗
PubMed1996

Activation of human effector cells by a tumor reactive recombinant anti-ganglioside GD2 interleukin-2 fusion protein (ch14.18-IL2).

Cytotoxic effector cells interact with target cells through various mechanisms. CTLs use the antigen-specific T cell receptor, whereas Fc receptor-positive natural killer cells use this receptor to interact with antibody-coated target cells. We evaluated the tumor-binding and lymphocyte-activating capability of a recombinant fusion protein consisting of a tumor-selective human/mouse chimeric anti-ganglioside GD2 antibody (ch14.18) and recombinant human interleukin-2 (IL2) (ch14.18-IL2). This fusion protein bound specifically to GD2-positive melanoma and neuroblastoma tumor cell lines, and its IL2 component stimulated in vitro proliferation of an IL2-dependent cell line, as well as peripheral blood mononuclear cells, in healthy control individuals and in cancer patients receiving continuous infusion of IL2. The IL2 presented by the fusion protein, when bound to tumor cells, induced proliferation of IL2-responsive cells as well as a comparable amount of soluble IL2 did. This suggests that localization of IL2 at the site of contact between tumor and effector cells is an effective way of presenting this cytokine to IL2-responsive cells. The ch14.18-IL2 fusion protein also mediated antibody-dependent cellular cytotoxicity with Fc receptor-positive effector cells to an extent similar to ch14.18. These results, together with those of previous studies documenting antitumor efficacy against human tumor xenografts in SCID mice and GD2-positive murine tumors in immunocompetent syngeneic mice, suggest that the ch14.18-IL2 fusion protein should be tested in Phase I and II trials in patients with GD2-positive tumors.

Animals↗
PubMed1995

[Prevalence of medullary sponge kidney in patients with and without nephrolithiasis].

Reports on the prevalence of medullary sponge kidneys have given conflicting results. The present work is aimed at defining the prevalence of this abnormality in renal stone formers compared with a non-stone-forming control population by strict radiological criteria. Three separate studies have been carried out: the retrospective analysis of 191 intravenous urographies, which had been performed in 1988; the respective prospective analysis of 104 consecutive intravenous urographies and of 149 consecutive urographies, which had been performed at the end of intravenous digitalized subtraction renal angiographies. The 444 patients were classified according to presence or absence of nephrolithiasis. After exclusion of 70 patients (16%) of which the X-ray didn't fulfill the quality criteria, urographies were classified as 'medullary sponge kidneys', 'papillary blush' or 'negative' according to the radiological aspect of the papillae. Diagnosis of medullary sponge kidneys was based on presence of at least three linear or round papillary opacities seen in at least on papilla even of one kidney on late films (at least ten minutes after injection of contrast medium), taken without ureteral obstruction or abdominal compression. Overall results reveal that prevalence of a medullary sponge kidney in renal stone formers (8.5%) is significantly (p < 0.01) higher than in the control population (1.5%) and higher than what has been generally reported. Results of the retrospective and of both prospective analysis did not significantly differ. The best diagnostic tool to unmask medullary sponge kidneys remains urography.

Angiography, Digital Subtraction↗
PubMed1995

Simultaneous measurements of calcium oxalate crystal nucleation and aggregation: impact of various modifiers.

Rates of nucleation and aggregation of calcium oxalate crystals were derived from 20-min time course measurements of OD620 after mixing solutions containing CaCl2 and K2C2O4 at 37 degrees C, pH 5.7, ionic strength (IS) 0.21, with constant stirring (500 rpm); final assay concentrations were 4.25 mM calcium and 0.5 mM oxalate, respectively. The maximum increase of OD620 with time, termed SN, mainly reflects maximum rate of formation of new particles and thus crystal nucleation. After equilibrium has been reached, OD620 progressively decreases despite ionized calcium staying constant and no new particles being formed, due to crystal aggregation. Rate of aggregation, SA, is derived from the maximum decrease in OD620 with time. SN and SA are not independent, as indicated by a positive correlation (r = 0.844, P = 0.0001). Among the modifiers studied, citrate at 0.5-2.5 mM lowered both SN and SA in a concentration-dependent manner (P < 0.01 for all comparisons vs control). Chondroitin-6-sulfate at 6.25-25 mg/l moderately lowered SN, whereas it strongly inhibited aggregation (P < 0.01 vs control). At 6.8-20.4 mg/l, albumin did not affect nucleation, whereas it inhibited aggregation in a concentration-dependent manner (P < 0.005 vs control for all comparisons).

Calcium Oxalate↗
PubMed1995

Different effects of cyclosporin A on bone remodeling in young and adult rats.

Reported effects of cyclosporin A (Sandimmun, CsA) on bone have been both contradictory and controversial. Thus, stimulation of new bone formation as well as increased mineral and matrix resorption have been observed. To investigate the response of basal mineral and matrix turnover to CsA treatment at different stages of skeletal development, comparative experiments were conducted in young growing female rats and in adults. Fifty-six young animals (study A) and 40 adults (study B) received orally either the carrier substance or 5, 15, and 30 mg/kg CsA for 30 days. The following parameters were measured: (a) total skeletal mineral content by dual energy X-ray absorptiometry (DEXA) on days 1 and 30; (b) tibial trabecular volume at day 30; (c) serum osteocalcin at 5-day intervals; (d) urinary deoxypyridinoline (Dpd) excretion (days 1, 15, and 30); and (e) plasma levels of CsA. Results can be summarized as follows: in young rats (study A), total skeletal mineral was not modified by the 5- and 15-mg/kg doses of CsA, whereas 30 mg/kg induced a significant decrease (-15%, p < 0.01). This parameter was not significantly modified in adult animals (study B) subjected to the same doses. The administration of 5 mg/kg CsA did not alter tibial trabecular volume in young rats, but 15 and 30 mg/kg significantly lowered this parameter (-16.3%, p < 0.02, and -42%, p < 0.001, respectively). In adult rats, tibial trabecular volume remained unchanged with the exception of the group receiving 30 mg/kg which exhibited significantly lower values (-28%, p < 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)

Absorptiometry, Photon↗
PubMed1995

Bone mass at lumbar spine and tibia in young males--impact of physical fitness, exercise, and anthropometric parameters: a prospective study in a cohort of military recruits.

Bone mineral density (BMD) and bone mineral content (BMC) were measured using DXA at lumbar spine and tibial diaphyses at the beginning and at the end of a 15-week training period in 151 military recruits of the Swiss army belonging to 5 different troop categories (infantry grenadiers, tank drivers, tank gunners, signalmen, and privates) who each were exposed to physical training of various intensity. At baseline, height, body mass index, and degree of physical fitness independently correlated with vertebral and tibial BMD. Over the 15 weeks of physical training BMD at tibial diaphyses increased by 2.2 +/- 0.3% at the left leg (p = 0.0001) and by 1.1% at the right leg (p = 0.002) with differences between troop categories. At lumbar spine, BMD decreased significantly in tank drivers (-1.2 +/- 0.4%, p = 0.001) and particularly in infantry grenadiers (-2.1 +/- 0.4%) who had the most strenuous weight-bearing training, but not in other troop categories. This decrease was twice as large at the center of the vertebra than for the whole vertebra. These BMD changes were associated with increments in serum levels of osteocalcin and alkaline phosphatase activity. From the initial cohort, 48 subjects volunteered for a third investigation carried out 2 years after the end of the military training period. At this time, lumbar BMD and BMC had risen back to baseline, whereas at tibial diaphyses bone width and BMC but not BMD increased by 5.8 +/- 1.1% and 6.2 +/- 0.9%, respectively, vs. baseline (p = 0.0001 for both).(ABSTRACT TRUNCATED AT 250 WORDS)

Absorptiometry, Photon↗
PubMed1995

Ultrastructural modification of human skeletal muscle tissue with 6-month moderate-intensity exercise training.

The study was aimed at investigating if endurance training of moderate intensity and longer duration, intended to promote health rather than performance, evokes ultrastructural changes in skeletal muscle tissue comparable to those observed after high-intensity protocols. Twenty healthy, middle-aged men enrolled in a 6-month, home-based jogging program of 120 min/wk at 75% VO2max. Only 12 men showed a sufficient exercise adherence over the 6 months (> or = 60 min/wk on average) and were included into statistical analysis. Their average training activity was 105 +/- 31 min/wk. The results revealed significant increases in VO2max (+8.4%, p < 0.01) and submaximal power output (+18.1%, p < 0.01). Total mitochondrial volume density in M. vastus lateralis increased by 20% (p < 0.05) with a larger increase in subsarcolemmal volume compared to central volume (50% vs 15%). No changes in volume of intracellular lipid droplets, capillary density, capillary per fiber ratio, fiber mean cross-sectional area and muscle fiber type could be observed. Body composition analysis showed a decrease in trunk fat mass (-7.3%, p < 0.05) and an increase in trunk lean mass (+1.7%, p < 0.05), while changes in the legs were not significant. It can be concluded that a moderate-intensity, health oriented endurance training beneficially affected cardiovascular and muscle oxidation capacity as well as body composition in the trunk area. No adaptations in capillaries or lipid metabolism could be demonstrated. The results support the hypothesis of thresholds for induction of adaptation processes in muscle skeletal tissue depending on the intensity of the exercise stimulus.

Adipose Tissue↗
PubMed1995

Body composition and fuel metabolism after kidney grafting.

Kidney transplant patients display decreased muscle mass and increased fat mass. Whether this altered body composition is due to glucocorticoid induced altered fuel metabolism is unclear. To answer this question, 16 kidney transplant patients were examined immediately after kidney transplantation (12 +/- 4 days, mean +/- SEM) and then during months 2, 5, 11 and 16, respectively, by whole body dual energy X-ray absorptiometry (Hologic QDR 1000W) and indirect calorimetry. Results were compared with those of 16 age, sex and body mass index matched healthy volunteers examined only once. All patients received dietary counselling with a step 1 diet of the American Heart Association and were advised to restrict their caloric intake to the resting energy expenditure plus 30%. Immediately after transplantation, lean mass of the trunk was higher by 7 +/- 1% (P < 0.05) and that of the limbs was lower by more than 10% (P < 0.01) in patients than in controls. In contrast, no difference in fat mass and resting energy expenditure could be detected between patients and controls. During the 16 months of observation, total fat mass increased in male (+4.9 +/- 1.5 kg), but not in female patients (0.1 +/- 0.8 kg). The change in fat mass observed in men was due to an increase in all subregions of the body analysed (trunk, arms+legs as well as head+neck), whereas in women only an increase in head+neck by 9 +/- 2% (P = 0.05) was detected. Body fat distribution remained unchanged in both sexes over the 16 months of observation. Lean mass of the trunk mainly decreased between days 11 and 42 (P < 0.01) and remained stable thereafter. After day 42, lean mass of arms and legs (mostly striated muscle) and head+neck progressively increased over the 14 months of observation by 1.6 +/- 0.6 kg (P < 0.05) and 0.4 +/- 0.1 kg (P < 0.01), respectively. Resting energy expenditure was similar in controls and patients at 42 days (30.0 +/- 0.7 vs. 31.0 +/- 0.9 kcal kg-1 lean mass) and did not change during the following 15 months of observation. However, composition of fuel used to sustain resting energy expenditure in the fasting state was altered in patients when compared with normal subjects, i.e. glucose oxidation was higher by more than 45% in patients (P < 0.01) during the second month after grafting, but gradually declined (P < 0.01) over the following 15 months to values similar to those observed in controls. Protein oxidation was elevated in renal transplant patients on prednisone at first measurement, a difference which tended to decline over the study period. In contrast to glucose and protein oxidation, fat oxidation was lower in patients 42 days after grafting (P < 0.01), but increased by more than 100% reaching values similar to those observed in controls after 16 months of study. Mean daily dose of prednisone per kg body weight correlated with the three components of fuel oxidation (r > 0.93, P < 0.01), i.e. protein, glucose and fat oxidation. These results indicate that in prednisone treated renal transplant patients fuel metabolism is regulated in a dose-dependent manner. Moreover, dietary measures, such as caloric and fat intake restriction as well as increase of protein intake, can prevent muscle wasting as well as part of the usually observed fat accumulation. Furthermore, the concept of preferential upper body fat accumulation as consequence of prednisone therapy in renal transplant patients has to be revised.

Adipose Tissue↗
PubMed1995

Morphological and functional changes in canine kidneys following extracorporeal shock-wave treatment.

Extracorporeal shock-wave lithotripsy (ESWL) has rapidly become established worldwide as a routine method for treatment of nephro- and ureterolithiasis. Although initial studies showed no tissue-damaging effect by the shock waves, we found, in an animal experiment using canine kidneys, that the ESWL-induced damage to the renal parenchyma is more marked than originally assumed. The damage is limited to the area that was focused on, and heals relatively rapidly by connective tissue encapsulation with final cicatrisation without any further residual effects being observed up to the present. This parenchymal damage is probably also the cause of the macrohematuria that is always observed during therapy. The resulting tissue damage is not extensive enough to cause a demonstrable reduction of function as measured by the usual methods (serum creatinine, creatinine clearance, isotopy renography, i.v. urography). In serum we observed a transient decrease of calcium, an immediate increase of lactate-dehydrogenase, transaminases (SGOT and SGPT) and a delayed increase of alkaline phosphates. Creatinine, blood urea nitrogen, sodium, potassium and amylase remained within normal limits. In urine, a decrease of creatinine and an increase of glucose excretion were noted. We believe that these changes represent a relatively mild and transient damage of renal cells and do not reflect the occasionally heavy morphological changes observed after shock-wave exposure. The main clinical complication is the large subcapsular hematoma which, according to the present knowledge, could well result from a lesion of the larger peripheral vessels. Damage to other organs such as subserous colonic and small bowel hematomata are to be expected although they do not lead to clinical symptoms.

Animals↗
PubMed1995

Evidence for disturbed regulation of calciotropic hormone metabolism in gitelman syndrome.

Little attention has been paid to interactions between circulating levels of calcium, PTH, and 1,25-dihydroxycholecalciferol [1,25(OH)2D] and bone mineral density in primary renal magnesium deficiency. Plasma and urinary electrolytes, and circulating levels of calciotropic hormones were studied in 13 untreated patients with primary renal tubular hypokalemic alkalosis with hypocalciuria and magnesium deficiency. The blood ionized calcium concentration was significantly lower in patients than in controls. Despite this fact, PTH and 1,25-(OH)2D levels were similar in both groups of subjects. The negative linear relationships between PTH and ionized calcium, which significantly differed between Gitelman patients and healthy subjects in terms of intercept; the negative relationship between ionized calcium and 1,25-(OH)2D, which was comparable in both groups; and the positive relationship between 1,25-(OH)2D and PTH, which was identical in both groups, point both to a blunted secretion of PTH induced by magnesium depletion and to the lack of interference of the latter with the activation of 1 alpha-hydroxylase by PTH. The similar bone mineral density at the lumbar spine by dual energy x-ray absorptiometry in 11 patients and 11 healthy subjects argues against chronically sustained negative calcium balance.

Adolescent↗
PubMed1995

Renal mass and serum calcitriol in male idiopathic calcium renal stone formers: role of protein intake.

To determine whether chronic overconsumption of protein might increase renal mass and cause up-regulation of 1,25-dihydroxyvitamin D3 [1,25-(OH)2D] production, 57 male recurrent idiopathic calcium stone formers (RCSF), 29 with hypercalciuria (HCSF; urinary calcium x V, > 7.50 mmol/day) and 28 with normocalciuria (NCSF), were compared with 15 healthy male controls (C) while consuming a free choice diet. Renal mass in RCSF was measured by the sum of the surface areas of right and left kidneys (square centimeters) on plain films of the abdomen by a computer-assisted sonic stylus; in C, renal mass was assessed sonographically. Serum intact PTH and 1,25-(OH)2D were measured radioimmunometrically. In HCSF, urinary phosphate x V (35.9 +/- 1.2 mmol/day) was higher than that in NCSF (29.3 +/- 1.3 mmol/day; P = 0.0009) or C (28.7 +/- 1.8 mmol/day; P = 0.005); urinary creatinine x V (16.5 +/- 0.5 mmol/day) was also higher in HCSF than in NCSF (15.0 +/- 0.5 mmol/day; P = 0.024) or C (13.8 +/- 0.6 mmol/day; P = 0.002). For identical blood levels of ionized calcium and phosphate, the 1,25-(OH)2D/PTH concentration ratio (an index of regulation of 1,25-(OH)2D production) was higher in HCSF (6.5 +/- 1.0) than in NCSF (4.0 +/- 0.3; P = 0.005). In addition, the sum of the surface areas of right and left kidneys was increased in HCSF (163.4 +/- 2.9 cm2) compared with that in NCSF (140.5 +/- 3.1 cm2; P = 0.0001), and it positively correlated with urinary phosphate x V (r = 0.429; P = 0.001) as well as with urinary creatinine x V (r = 0.294; P = 0.026); no such correlation was noted in C. Calcitriol levels were positively related to renal mass in RCSF (r = 0.316; P = 0.018), but not in C. Finally, urinary calcium x V positively correlated with the serum calcitriol/PTH concentration ratio only in RCSF (r = 0.388; P = 0.003). These findings suggest that protein overconsumption may cause an increase in renal mass and up-regulate calcitriol production in some male RCSF, an effect that would subsequently cause "idiopathic" hypercalciuria.

Adult↗
PubMed1995

Impact of chronic cigarette smoking on body composition and fuel metabolism.

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.

Adult↗
PubMed1995

Effect of oral calcium loading on intact PTH and calcitriol in idiopathic renal calcium stone formers and healthy controls.

The calciuric response after an oral calcium load (1000 mg elemental calcium together with a standard breakfast) was studied in 13 healthy male controls and 21 recurrent idiopathic renal calcium stone formers, 12 with hypercalciuria (UCa x V > 7.50 mmol/24 h) and nine with normocalciuria. In controls, serum 1,25(OH)2 vitamin D3 (calcitriol) remained unchanged 6 h after oral calcium load (50.6 +/- 5.1 versus 50.9 +/- 5.0 pg/ml), whereas it tended to increase in hypercalciuric (from 53.6 +/- 3.2 to 60.6 +/- 5.4 pg/ml, P = 0.182) and fell in normocalciuric stone formers (from 45.9 +/- 2.6 to 38.1 +/- 3.3 pg/ml, P = 0.011). The total amount of urinary calcium excreted after OCL was 2.50 +/- 0.20 mmol in controls, 2.27 +/- 0.27 mmol in normocalciuric and 3.62 +/- 0.32 mmol in hypercalciuric stone formers (P = 0.005 versus controls and normocalciuric stone formers respectively); it positively correlated with serum calcitriol 6 h after calcium load (r = 0.392, P = 0.024). Maximum increase in urinary calcium excretion rate, delta Ca-Emax, was inversely related to intact PTH levels in the first 4 h after calcium load, i.e. more pronounced PTH suppression predicted a steeper increase in urinary calcium excretion rate. Twenty-four-hour urine calcium excretion rate was inversely related to the ratio of delta calcitriol/deltaPTHmax after calcium load (r = -0.653, P = 0.0001), indicating that an abnormally up-regulated synthesis of calcitriol and consecutive relative PTH suppression induce hypercalciuria.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1994

[Sulfadiazine nephrolithiasis and nephropathy].

Sulfadiazine-nephropathy and -nephrolithiasis were well known complications of high dose sulfadiazine therapy 50 years ago. In the last few years high dose sulfadiazine therapy has been widely used for treatment of toxoplasmic encephalitis in AIDS patients. As a consequence sulfadiazine-nephropathy and -nephrolithiasis have become increasingly common. We describe 2 patients with the typical picture of these complications. Therapy is based on the fact that the solubility of sulfadiazine and its acetylated metabolite are markedly improved at higher urine-pH levels. Urine alkalinization is also effective for prophylaxis during sulfadiazine treatment. We present our guidelines for prophylaxis and treatment of these complications.

AIDS-Related Opportunistic Infections↗
PubMed1994

[Assessment of parathyroid gland function: predictive value of a nomogram].

Recent developments in measurement of intact parathormone (PTH) has enabled to generate a nomogram for parathyroid function. Blood levels of PTH can thus be interpreted in relation to calcemia. Intact PTH and calcium were assayed in blood from 99 healthy subjects studied under fasting conditions; 26 subjects were also studied during hyper- and hypocalcemia, induced by calcium and EDTA infusions, respectively. Serum levels of intact PTH which had been obtained in 99 patients were then analysed retrospectively by comparison with the nomogram. Patients whose intact PTH levels lie above the normal zone of the nomogram produce too much PTH relative to the blood calcium level (hyperparathyroidism); those falling under the normal zone produce too little (hypoparathyroidism).

Adolescent↗