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S Ortolani

Publications and source records attributed to S Ortolani.

At least 55 records · Page 3Linked to original sources

Quantification by dual photonabsorptiometry of local bone loss after fracture.

Total bone mineral and bone mineral density modifications were evaluated during fracture healing of long bones in patients with traumatic fractures of the lower limbs, using an experimental model based on the dual photonabsorptiometry technique. Seven patients (five males and two females; mean age, 19.5 years; range, 17-23 years) with tibia and fibula midshaft open fractures treated with osteosynthesis were studied. Dual energy gadolinium-153 photonabsorptiometry was used to measure distal leg bone loss at a skeletal segment distant from the fracture to exclude callus formation. Total bone mineral (TBM) and bone mineral density (BMD) of the tibia and fibula both in the fractured leg and in the healthy contralateral leg were measured on Days 10, 20, 30, 40, 60, and 120 after trauma. TBM and BMD of the healthy contralateral leg did not present any significant modifications at the different observation times. Both TBM and BMD of the fractured leg showed a progressive reduction that reached statistical significance starting on Day 30 with maximum reduction on Day 120 when TBM and BMD were reduced to almost one-half the initial value.

Absorptiometry, Photon↗

Bone mineral density in adult celiac patients and the effect of gluten-free diet from childhood.

Peripheral single photon absorptiometry was used to measure forearm bone mineral density in 22 celiacs on gluten-free diet from childhood (male 14, female 8, age 13-20) and 29 untreated adult celiacs at diagnosis (male 5, female 24, age 18-56, 14 with subclinical disease), compared with healthy sex- and age-matched controls. Bone mineral density was similar in patients treated from childhood and their controls [(668.4 +/- 65.3 vs. 654.9 +/- 69.6 mg/cm2, (mean +/- SD)], but significantly lower in untreated patients than in their controls (598.3 +/- 83.1 vs 673.2 +/- 42.7 mg/cm2, p less than 0.001). It was also significantly lower in the 12 younger untreated celiacs (18-28 yr) versus controls (619.4 +/- 68.5 vs 669.1 +/- 39.3 mg/cm2, p less than 0.01). In the untreated women, but not their controls, a negative correlation (p less than 0.05) was observed between bone mineral density and age. Bone mineral density did not correlate with severity of clinical or biochemical abnormalities. These results suggest that bone derangements are common in celiacs diagnosed in adulthood, even if they never presented evident malabsorption symptoms, and emphasize the importance of early diagnosis and treatment.

Absorptiometry, Photon↗

Bone involvement in primary hemochromatosis and alcoholic cirrhosis.

Biochemical indexes of bone metabolism, bone mineral density, and histomorphometry were evaluated in 14 male patients with noncholestatic cirrhosis due to primary hemochromatosis (six cases) or to chronic alcohol abuse (eight cases), and in 30 male controls of similar age. Alkaline phosphatase in alcoholic patients was significantly higher than in controls (mean +/- SD 50.4 +/- 33.7 vs 33.0 +/- 7.1 U/L, p less than 0.01), as was urinary hydroxyproline in both hemochromatotics and alcoholics (mean +/- SD, 44.3 +/- 8.4 and 40.4 +/- 16.8, respectively, vs 30.1 +/- 4.5 mg/g, p less than 0.001 and p less than 0.005). Bone mineral density was significantly lower in hemochromatotics than in alcoholics and controls (mean +/- SD, 591 +/- 90 vs 765 +/- 87 and 759 +/- 34 mg/cm2, respectively, p less than 0.005 and p less than 0.001). At bone biopsy, trabecular osteoporosis was observed in two hemochromatotics and four alcoholics, and osteomalacia was seen in another alcoholic. Overall densitometric and histomorphometric findings indicate a derangement of trabecular bone in both alcoholic and hemochromatotic cirrhosis, whereas cortical osteoporosis seems limited to hemochromatotic patients.

Alkaline Phosphatase↗

Bone and mineral metabolism in adult celiac disease.

Bone mineral density (125I photon absorptiometry) was lower in 20 untreated adult celiac patients than in sex- and age-matched controls (p less than 0.001), and plasma alkaline phosphatase, parathyroid hormone, urinary hydroxyproline/creatinine levels were higher than normal (p less than 0.05, less than 0.001, less than 0.05, respectively). Gluten-free diet was started, and the patients were divided randomly into two treatment groups, one which received oral 25-hydroxyvitamin D 50 micrograms/day and one which did not. After 12 months' treatment, bone turnover markers showed a decrease, which did not reach statistical significance, and bone mineral density did not show significant modifications compared with base line in either group. It was found that a gluten-free diet followed for 1 yr can prevent further bone loss, but no significant differences were detected between the two groups.

25-Hydroxyvitamin D 2↗

Effects of 1,25-dihydroxyvitamin-D3 treatment on mineral balance in children with end stage renal disease undergoing chronic hemofiltration.

Ten children with end stage renal disease on chronic hemofiltration (HF) were studied for a 1-yr period to evaluate the efficacy of 1,25-dihydroxyvitamin-D3 (1,25(OH)2D3) therapy on biohumoral parameters of renal osteodystrophy and bone mineral content. In six of these children an acute study was done of the direct effect of the HF procedure on calcium and phosphate balance during 12 HF sessions. During the first 6 months of the study all children were treated with 1,25(OH)2D3 (0.25-0.50 microgram/day) to maintain plasma calcium at 9.5-11.0 mg/dl. There was a significant increase in plasma calcium (p less than 0.05) and a significant decrease in plasma phosphate (p less than 0.01) and alkaline phosphatase concentrations (p less than 0.05). The circulating levels of NH2 immunoreactive parathyroid hormone did not change, remaining at the upper limits of reference values. Immunoreactive parathyroid hormone-COOH terminal fragment levels decreased significantly (p less than 0.05). Bone mineral content rose significantly (p less than 0.01). During the last 6 months of the study, to evaluate the possibility that HF alone might control secondary hyperparathyroidism, 1,25(OH)2D3 treatment was discontinued in five children; plasma calcium and phosphate were well controlled whereas hyperparathyroidism worsened in all five, and one also developed intense pruritus and hypertension. The other five children remained on 1,25(OH)2D3 treatment; two of these were transplanted, and the other three continued to show an improvement of mineral balance. The results of the acute study showed that calcium balance was positive with a mean Ca++ gain of 140 mg/HF session. The mean total phosphate removed per HF run was 574 mg.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

Progression of mineral metabolism derangements in childhood chronic renal failure.

2 groups of children affected by different degrees of chronic renal failure (group 1, 55-36 ml/min/1.73 m2; group 2, 35-20 ml/min/1.73 m2 of creatinine clearance) due to tubulo-interstitial disease were studied for one year. The spontaneous evolution of altered mineral metabolism at different levels of glomerular filtration rate (GFR) was aimed at. Parathyroid hormone, vitamin D metabolites and bone mineral content were evaluated. At the end of the year, only a decrease of plasma levels of 1,25(OH)2D in group 1 and a worsening of all mineral metabolism parameters in group 2 were found. The results are consistent with the hypothesis that mineral metabolism derangements progress rapidly after a certain 'threshold' of endocrinologically active renal mass is reached. The falling of plasma 1,25(OH)2D levels below a still undetermined critical value might be assumed as an index of this threshold.

Adolescent↗

Vitamin D concentrations in women of postmenopausal age with fractures of the femoral neck.

Thirty-eight women of postmenopausal age, suffering from fractures of the femoral neck or vertebral bodies were studied in relation to differences in bone metabolism. The blood and urinary changes concerned in mineral and bone metabolism were recorded within 10 days of trauma, and in some femoral neck fractures, a histological study of the femoral heads removed in the course of prosthetic substitution was carried out. The patients with femoral neck fractures were older than those with vertebral fractures and had metabolic and histological findings suggestive of osteomalacia. A particularly significant difference between the two groups was the plasma level of 25 hydroxycholecalciferol, which was lower in femoral neck fractures, and the urinary excretion of calcium, which was also more reduced in femoral neck fractures. A deficit of vitamin D hepatic metabolite thus appears to be a risk factor for femoral neck fractures in old patients.

Aged↗

Mineral metabolism during a hemofiltration session in children.

We studied the effects of one session of hemofiltration on the mineral metabolism in a group of uremic children. We observed an increase of calcemia, accompanied by positive calcium balance, and a decrease of plasma phosphate and PTH-MM. No substantial loss of plasma 25-OH D was found. It is concluded that hemofiltration has a positive effect on calcemia and is very effective in removing phosphate, but it acts only temporarily on PTH removal. An adequate calcium concentration must be provided in the substitution fluid.

Adolescent↗

Increased forearm bone mineral content after bromocriptine treatment in hyperprolactinemia.

We studied 15 hyperprolactinemic women to evaluate possible modifications of bone mineral content after pharmacological treatment. Patients received a dopamine agonist (bromocriptine) for six months after which there was a significant decrease of prolactin plasma levels (P less than 0.01) and a significant increase of bone mineral content (P less than 0.05).

Adolescent↗

Basal plasma levels of calcitonin and bone mineral mass in normal and uremic women. Effect of menopause.

Basal plasma levels of immunoreactive calcitonin (iCT), forearm bone mineral content (BMC) as measured by 125I photon absorptiometry and 24-hour urinary hydroxyproline/creatinine ratio (OHPr/Cr) were determined in 32 healthy women (13 pre-menopausal, aged 40 to 54 years, and 19 post-menopausal, aged 41 to 54 years). The basal plasma levels of iCT were significantly higher in the pre-menopausal group (mean value 96 vs 54 pg/ml, P less than 0.025). The BMC value of the radius was also significantly greater in the same group (mean +/- SEM 656 +/- 13 vs. 620 +/- 9 mg/cm2, P less than 0.05), while the urinary OHPr/Cr ratio was higher in the post-menopausal group (29.9 +/- 1.5 vs. 38.7 +/- 2.7 mg/g, P less than 0.02). These results suggest that basal plasma levels of iCT decrease after the menopause and support the hypothesis that a deficiency of CT could be involved in the pathogenesis of post-menopausal bone loss. Similar results were obtained in 25 uremic women on maintenance hemodialysis (9 pre-menopausal and 16 post-menopausal) aged 30 to 65 yrs.: both basal iCT levels and BMC values were significantly higher in the pre-menopausal group.

Adult↗

Effects of porcine calcitonin on human platelet fuction.

The effects of different doses of porcine calcitonin (pCT) were tested in vitro and in vivo. In vitro, pCT at a concentration ranging from 0.1 to 5 M. R. C. Units/ml induced a dose-dependent inhibition of ADP (1.2 microM) and collagen- (2 micrograms/ml) induced platelet aggregation, showing a prevalent action on the second wave of ADP-induced aggregation and causing prolongation of the lag time and reduction of both maximum aggregation and slope in collagen-induced aggregation. 45Ca uptake by platelets in the presence of the ionophore A23187 and 14C-serotonin release were also inhibited in a dose-related fashion, using concentrations ranging from 1 to 10 M. R. C. Units of pCT. The in vivo tests, performed before and after a 7-day treatment with 2 different doses of pCT (1 and 160 M. R. C. Units/daily, i. m.) confirmed the inhibitory effect of pCT on ADP- and collagen-induced platelet aggregation. It should be stressed that the effect of 1 unit was stronger than that of 160 units. It is therefore postulated that in vitro and in vivo effects of pCT on platelet functions probably depend on different mechanisms of action.

Adult↗

Plasma immunoreactive N-terminal parathyroid hormone and cyclic AMP and cyclic GMP urinary levels in man after I. M. administration of two different doses of porcine calcitonin.

The effects of acute porcine calcitonin (pCT) administration were studied in 11 healthy volunteers with no metabolic disease. Each subject was given, intramuscularly, 1 MRC unit of pCT in glycine vehicle, 160 units of pCT in gelatine vehicle, and placebo, according to a crossover design. The following parameters were studied: blood calcium, phosphorus and immunoreactive parathyroid hormone (iPTH); urine calcium, phosphorus, cyclic AMP and GMP. Both the pCT preparations produced, at the same time after administration, a hypocalcemic effect (P less than 0.01) which was not dose related, without any modification of urinary calcium excretion, implying that both doses are able to inhibit completely bone destruction. Despite the blood calcium decrease, no significant modifications in plasma iPTH levels were observed. pCT administration did not modify the urinary excretion of cyclic AMP, while it increased the urinary levels of cyclic GMP, particularly at the higher dose employed. Blood phosphorus decrease and urinary phosphate excretion increase were observed only after the administration of 160 MRC units of pCT. These observations suggest that the effects on urinary cyclic GMP and on blood and urine phosphorus are not mediated by PTH but could be the result of a direct action of calcitonin seen only when high doses are employed. In conclusion, one MRC unit of pCT is sufficient to inhibit bone resorption.

Adult↗