Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0020438 (hypercalciuria)
 2,502 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Plasma osteocalcin levels were measured by radioimmunoassay in 70 consecutive patients with recurrent calcium (sterile) nephrolithiasis during diagnostic evaluation for the cause of the disease. Nephrogenous cyclic adenosine 3,5'-monophosphate levels also were measured in most of the subjects. Included in the sampling, as determined by standard diagnostic criteria, were 12 patients with absorptive hypercalciuria type I, 15 with absorptive hypercalciuria type II, 22 with renal leak hypercalciuria, 11 with normocalciuria, 6 with primary hyperparathyroidism, 3 with renal tubular acidosis and 1 with Paget's disease, as well as 12 control subjects. The observed plasma osteocalcin levels (ng. per ml. mean +/- standard error) were absorptive hypercalciuria I 2.6 +/- 0.20, absorptive hypercalciuria II 3.1 +/- 0.21, renal hypercalciuria 8.7 +/- 0.45, normocalciuric nephrolithiasis 3.3 +/- 0.25, primary hyperparathyroidism 13.2 +/- 0.91, renal tubular acidosis (range) 5.2 to 10.6, Paget's disease 18.0 and control 3.1 +/- 0.20. There were significant differences between the plasma osteocalcin levels of renal hypercalciuria versus primary hyperparathyroidism and renal hypercalciuria/primary hyperparathyroidism versus any other group. There was good correlation between plasma osteocalcin and cyclic adenosine 3,5'-monophosphate data (correlation coefficient 0.72, p less than 0.005). Plasma osteocalcin levels are a potential differential diagnostic tool for patients with stone disease. The diagnostic value compares favorably with that of cyclic adenosine 3,5'-monophosphate, with the advantage that the determination of plasma osteocalcin requires only a single test.
 ...
PMID:Plasma osteocalcin levels in stone disease. A potential aid in the differential diagnosis of calcium nephrolithiasis. 282 25

The effects of glucocorticoids on calcium and bone metabolism were investigated in 11 children (aged 6 months to 13 years) who were treated with dexamethasone, prednisolone and depot-ACTH because of different disorders. Alkaline phosphatase activity and osteocalcin in serum, representing indices of osteoblastic bone synthesis, and urinary hydroxyproline in relation to creatinine in morning fasting urine specimens, an index of osteoclastic bone degradation, decreased by 53-61% from baseline (P less than 0.01), with a highly significant relationship of all 3 indices to each other. Additional influences of glucocorticoids were hyperphosphaturia due to decreased renal phosphate reabsorption not mediated by secondary hyperparathyroidism, as well as marked hypercalciuria. As the consequence of the present study the following prophylactic or therapeutic recommendations are given during steroid-treatment: 1. Approvement of the negative balance of calcium and phosphate by correcting the hypercalciuria with hydrochlorothiazide, and the hypophosphatemia with oral phosphate and 2. in elder children with osteoporosis, stimulation of the decreased osteoblastic bone formation by sodium fluoride.
 ...
PMID:[Disorders of calcium and bone metabolism in glucocorticoid treatment]. 284 91

The results are presented of an oral calcium tolerance test with 1,000 mg calcium in 20 patients with recurrent renal calcium calculosis, a woman with primary hyperparathyroidism and incipient renal failure (serum creatinine 1.8 mg%), creatinine clearance 55 ml/min) and 9 healthy persons as controls. The serum osteocalcin level was determined before and after the oral test. The results show that the serum osteocalcin level alone is of no differential diagnostic value for differentiation of the various types of hypercalciuria in patients with recurrent renal calcium calculosis. As a marker of osteoblasts functional state however the determination of serum osteocalcin level is of great importance for the early diagnosis of osteoporosis. In 3 patients with renal hypercalciuria, often leading to general osteoporosis, an acute rise of serum osteocalcin level was found after the oral calcium tolerance test. High osteocalcin level was also found in the patient with primary hyperparathyroidism and incipient renal failure.
 ...
PMID:[Serum osteocalcin level as a marker of the functional state of osteoblasts after oral calcium tolerance test]. 326 44

Osteocalcin synthesis is dependent on the influence of the renal vitamin D metabolite, 1,25(OH)2D3. This metabolite is an etiological factor in some hypercalciurias, and osteocalcin may thus be a parameter for discovering them. In turn, parathormone, which stimulates 1,25(OH)2D3 synthesis, is also implicated in the hypercalciurias. Mean molecular parathormone, osteocalcin, 24-hour calciuria and the calcium/creatinine and hydroxyproline/creatinine ratios were determined in urine samples obtained after a 12-hour fast from 18 patients with absorptive hypercalciuria and 11 patients with renal hypercalciuria out of a total of 62 patients with renal lithiasis. No changes were observed in osteocalcin or parathormone, indicating that neither is valid for the diagnosis of hypercalciuria. Significant differences were only found in the Ca/Cr ratio (p less than 0.001), which was higher (0.31 +/- 0.07 vs. 0.13 +/- 0.04 mg/mg) in renal hypercalciuria than in absorptive hypercalciuria. No changes in osteocalcin have been reported in the hypercalciurias, but variations in parathormone have been reported, therefore requiring further study and thought to understand the processes involved.
 ...
PMID:Osteocalcin, parathormone and hypercalciuria. 326 5

Coffee drinking, smoking and especially alcohol abuse are considered to be risk factors for fractures and osteoporosis. Caffeine causes acute increase in urinary calcium excretion, but epidemiological evidence for the effects of coffee consumption on the risk of fractures is contradictory. Many, (but not all) studies point to decreased bone mass or increased fracture risk in smokers. Alcohol abuse is associated with deleterious changes in bone structure detected by histomorphometry, and with a decrease in bone mineral density (BMD). These changes may also be produced by factors commonly associated with alcohol abuse, e.g. nutritional deficiencies, liver damage and hypogonadism. Alcohol, however, has clear-cut direct effects on bone and mineral metabolism. Acute alcohol intoxication causes transitory hypoparathyroidism with resultant hypocalcaemia and hypercalciuria. As assessed by serum osteocalcin levels, prolonged moderate drinking decreases the function of osteoblasts, the bone-forming cells. In addition, chronic alcoholics are characterized by low serum levels of vitamin D metabolites. Thus, alcohol seems to have a direct toxic effect on bone and mineral metabolism. In contrast, it has recently been reported that moderate alcohol consumption by postmenopausal women may have a beneficial effect on bone.
 ...
PMID:Bone and the 'comforts of life'. 821 8

Urinary acidification, bone metabolism and urinary excretion of calcium and citrate were evaluated in 10 recurrent stone formers with incomplete renal tubular acidosis (iRTA), 10 recurrent stone formers with normal urinary acidification (NUA) and 10 normal controls (NC). Patients with iRTA had lower plasma standard bicarbonate after fasting (P < 0.01) and lower urinary excretion of titratable acid (P < 0.05) and citrate (P < 0.01) compared with NUA patients and NC, and higher urinary excretion of ammonia (P < 0.05) compared with NC (P < 0.05). Hypercalciuria was found in 6 of 10 patients with iRTA compared with 3 of 10 with NUA, and 0 of 10 NC. The citrate/calcium ratio in urine was significantly reduced in iRTA compared with the value in NUA (P < 0.01), and in NUA compared with NC (P < 0.05). Biochemical markers of bone formation (serum osteocalcin) and bone resorption (urinary hydroxyproline) were significantly increased in iRTA compared with NUA and NC (P < 0.01), indicating increased bone turnover in stone formers with iRTA. Stone formers with iRTA thus presented with disturbed calcium, bone and citrate metabolism--the same metabolic abnormalities which characterize classic type 1 RTA. Mild non-carbonic acidosis during fasting may be a pathophysilogical factor of both nephrolithiasis and disturbed bone metabolism in stone formers with iRTA.
 ...
PMID:Pathophysiology of incomplete renal tubular acidosis in recurrent renal stone formers: evidence of disturbed calcium, bone and citrate metabolism. 834 50

Burn patients are at risk for bone disease due to aluminum (Al) exposure from use of antacids and albumin, partial immobilization, and increased production of endogenous glucocorticoids. Moreover, severely burned children are growth impaired up to 3 years after the burn. To determine the extent of bone disease, we studied nine men and three women, ages 18-41 years, with greater than 50% body surface area burn. Seven patients underwent iliac crest bone biopsy following double tetracycline labeling, one additional patient expired after a single label, and three others had postmortem specimens obtained for quantitative Al only. Serial serum and urine samples were obtained weekly until biopsy or death. All biopsied patients had reduced bone formation and osteoid area, surface, and width, with mineral apposition rate, osteoblast surface, and osteoclast number with normal eroded surfaces compared to age- and sex-matched normal ambulatory volunteers. Burn patients also had reduced bone formation, mineral apposition rate, osteoid area, and surface compared to age-matched volunteers at short-term bed rest. Serum levels of osteocalcin were low. Most patients had mild hypercalcemia but only a third had hypercalciuria. All patients had elevated Al in blood or urine; urine Al correlated inversely with serum osteocalcin. In 60% significant bone Al was detectable by stain or quantitation. Our data are compatible with burn patients having markedly reduced bone turnover. Al loading, partial immobilization, endogenous corticosteroids, and cytokine production may be among the etiologic factors.
 ...
PMID:Bone disease in burn patients. 845 88

This study aimed to evaluate whether recombinant human growth hormone (rhGH) or insulin-like growth factor-I (rhIGF-I) can reverse or prevent further bone loss in aged osteopenic ovariectomized (OVX) rats and to compare their effects with those of 17 beta-estradiol (E2). Twelve-month-old rats were OVX, remained untreated for 8 weeks, and subsequently received daily subcutaneous (SC) injections of rhGH (75 micrograms/day), rhIGF-I (250 micrograms/day), E2 (1.5 micrograms/day), and their respective combinations during 8 weeks, and were then compared with sham-operated, pretreatment OVX, and saline-treated OVX rats. A single sc injection of rhGH resulted in peak hGH concentrations after 90 minutes, with a half-life of 124 minutes; the highest plasma IGF-I concentrations were reached 45 minutes after rhIGF-I injection (+57% vs. baseline) with a gradual decline thereafter. Measurements included: biochemical parameters of bone remodeling (plasma osteocalcin and urinary pyridinolines); histomorphometry of proximal tibial metaphysis; DXA of femur; biomechanical analysis of femur and fifth lumbar vertebra (L5); plasma 1,25-dihydroxyvitamin D3 (1,25(OH)2D3), and calbindin-D9K in duodenal mucosa. Whereas all E2-treated OVX rats had much suppressed bone remodeling, rhGH or rhIGF-I had no effect on any biochemical or histomorphometrical parameter of remodeling. The bone mineral density (BMD) at the distal femoral metaphysis as well as parameters of strength at L5 were maintained at pretreatment values in OVX rats treated with E2, GH, or IGF-I, but not in saline-treated OVX rats; their effects were not additive, however. Trabecular bone volume in the tibial metaphysis was also higher in rats treated with these agents than in saline-treated rats, but this was more apparent at the primary than at the secondary spongiosa, suggesting that their mechanism of action is on primary spongiosa formation or breakdown. E2 alone was ineffective to augment the BMD at the femoral diaphysis; however, the diaphyseal BMD was 12-14% higher (p < 0.01) after 8 weeks of GH treatment than in pretreatment or saline-treated OVX rats and sham-operated rats, while IGF-I was less effective than GH, GH or IGF-I treatment had no effect on plasma 1,25(OH)2D3 or duodenal calbindin-D9K concentrations, but the combination of GH or IGF-I with E2 potentiated the effect of E2 to stimulate calbindin-D9K concentrations and urinary calcium excretion, indicating "hyperabsorption hypercalciuria." In conclusion, the administration of rhGH and rhIGF-I, like that of E2, into aged OVX rats prevents further loss of bone mass and strength at sites containing trabecular bone. In addition, rhGH increases cortical bone mass above pretreatment values.
 ...
PMID:Effects of recombinant human growth hormone and insulin-like growth factor-I, with or without 17 beta-estradiol, on bone and mineral homeostasis of aged ovariectomized rats. 891 80

The differential effects of sodium-induced renal hypercalciuria on the biochemical markers of bone metabolism and calcium homeostasis were studied in oophorectomized (Oophx) and sham-operated rats. The rats consuming a normal (0.4%) calcium semisynthetic diet were randomly allocated to either 0, 0.4, 0.6, 0.9, or 1.25% NaCl in their drinking water for 7 days. At that time fasting blood and urine specimens were collected and analyzed for bone-related biochemical variables. The urinary calcium/creatinine ratio was increased with increasing urinary sodium (p < 0.01) in both sham and Oophx animals. The hydroxyproline/creatinine ratio was elevated as a result of Oophx (p < 0.001) and was raised with increasing urinary sodium in both sham (p = 0.012) and Oophx animals (p = 0.007). Serum osteocalcin and alkaline phosphatase were elevated in Oophx rats (p < 0.02). While serum osteocalcin was raised with increasing urinary sodium in Oophx rats (p = 0.035), there was no effect on osteocalcin levels in sham-operated rats. This study demonstrates that sodium-induced renal hypercalciuria potentiates bone turnover in Oophx rats as compared with ovary-intact rats and indicates important implications for the effect of dietary salt on bone turnover with ovarian hormone deficiency.
 ...
PMID:Increased urinary calcium excretion potentiates bone turnover in oophorectomized rats. 905 68

It is well known that some patients with renal lithiasis due to idiopathic hypercalciuria (IH) may exhibit decreased bone mineral density (BMD). We have studied a large group of children in IH and related their BMD values to several renal function parameters and calcium and bone metabolism markers. Children with IH had higher osteocalcin and calcitriol levels and higher urinary excretion of magnesium and prostaglandin E2, as well as lower tubular reabsorption of phosphate, urinary excretion of ammonium, maximum urinary PCO2, and BMD compared with control group of children. In children with IH we observed a negative correlation between BMD and age. We found osteopenia in 22 of 73 children with IH (30.1%); these children showed lower citraturia levels and higher fractional excretion of uric acid than children with normal BMD. In osteopenic children there was a negative correlation between BMD and calcitriol levels. Several possible pathogenetic factors have been proposed for the bone mass loss. Our results demonstrate that, at least in some cases, it may be related to high levels of calcitriol, which has a well-known resorption ability. Whether a certain degree of intracellular acidosis or a higher production of prostaglandin E2 could play a role in some cases is still an open question. In children with normal BMD we observed a direct correlation between osteocalcin and tartrate-resistant acid phosphatase levels; this correlation did not hold for children with osteopenia.
 ...
PMID:Bone mineral density in pediatric patients with idiopathic hypercalciuria. 932 83


<< Previous 1 2 3 4 Next >>