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Biomedical subjects

G Mazzuoli

Publications and source records attributed to G Mazzuoli.

At least 37 records · Page 2Linked to original sources
PubMed1994

Reduced serum levels of carboxy-terminal propeptide of human type I procollagen in a family with type I-A osteogenesis imperfecta.

We measured serum levels of total alkaline phosphatase activity, osteocalcin, carboxy-terminal propeptide of human type I procollagen (PICP), tartrate-resistant acid phosphatase activity (TRAP), and the fasting urinary hydroxyproline/creatinine ratio (OHPr/Cr) in seven affected members (four men, three women; age, 43.3 +/- 16.6 years [mean +/- SD]) of a family with clinically diagnosed type I-A osteogenesis imperfecta (OI) and in eight (five men, three women) normal age-matched (38.2 +/- 10.3) relatives. Three boys with OI and three normal girls of the same family were also studied, although they were excluded from statistical analysis. Bone mineral density was also determined at four different skeletal sites. Serum levels of PICP were measured with a radioimmunoassay (Farmos Diagnostica, Turku, Finland). There were no significant differences in mean values of the biomarkers studied between OI patients and normal relatives, with the only exception being serum levels of PICP (35 +/- 7.5 v 219 +/- 107.5 micrograms/L, P < .001). A significant reduction of BMD was found in OI patients compared with normal relatives at the lumbar (L) spine (680 +/- 61 v 1,128 +/- 92 mg/cm2, P < .001), at the ultradistal radius ([UDR] 323 +/- 85 v 458 +/- 76, P < .006), at the femoral neck ([F] 494 +/- 140 v 791 +/- 104, P < .001), and at the junction of the distal and middle third of the radius ([MR] 639 +/- 71 v 717 +/- 52, P < .029).(ABSTRACT TRUNCATED AT 250 WORDS)

Acid Phosphatase↗
PubMed1994

Serum carboxy-terminal propeptide of human type I procollagen in patients with primary hyperparathyroidism: studies in basal conditions and after parathyroid surgery.

This study was carried out in order to evaluate serum carboxy-terminal propeptide of human type I procollagen (PICP) in patients with primary hyperparathyroidism and to examine its changes following parathyroidectomy. Seventeen patients (four males and 13 famels, aged 53.8 +/- 3.1 SEM years) were studied in basal conditions; six patients also were investigated after successful parathyroid surgery. Mean serum PICP values of patients with primary hyperparathyroidism (194.5 +/- 27 SEM micrograms/l) were significantly higher (p < 0.001) with respect to those found in normal subjects. However, deviations from the norm (Z score values) were significantly less with respect to deviations of serum osteocalcin, alkaline phosphatase and urinary hydroxyproline/creatinine ratio. Following parathyroidectomy, it was possible to observe a discrepancy between markers of bone resorption and those of bone formation. The former tend to decrease, while the latter either do not show any significant change (serum alkaline phosphatase and serum osteocalcin) or increase (serum procollagen). The results of our investigation indicate that in basal conditions the assay of serum procollagen may be of clinical value but it would be better to use it in combination with other biomarkers of skeletal remodelling. The results obtained after parathyroidectomy are the opposite of those obtained following parathyroid hormone infusion and should be ascribed to the effect of acute hormone deficiency on collagen synthesis. The positive biochemical uncoupling following surgery might lend support to the rise of bone mineral density consistently reported in the first few months following parathyroidectomy.

Adenoma↗
PubMed1994

[Lung infections in acquired immunodeficiency. Clinico-radiologic correlations].

Over the last decade the number of subjects with acquired immunodeficiencies has markedly increased; this phenomenon depends on both the large number of patients receiving organ transplants or antiblastic therapy and the spread of infections caused by the HIV virus. In 70-90% of these patients primary diseases include different pulmonary infections, relative to the type and degree of immune compromission. Pathogenic or, in most cases, opportunistic germs are responsible for severe pneumonia whose mortality rate can top 50%. Since prognosis depends on the promptness of treatment, the diagnosis of nature must be made quickly by integrating clinical and diagnostic findings with laboratory and instrumental results. Conventional chest radiology plays a major role as the first step in a diagnostic iter which can now include rather sensitive techniques--e.g., equalized chest films. CT and nuclear medicine often represent the necessary diagnostic complements but, in some cases, etiology can be diagnosed only with such invasive procedures as lung biopsy. The authors reviewed the current data on the diagnostic imaging findings of pulmonary infections caused by common germs, by Pneumocystis carinii mycobacteria, mycetes and viruses in immunocompromised patients, integrating their personal experience with literature data.

AIDS-Related Opportunistic Infections↗
PubMed1993

Effect of estrogen deficiency on IGF-I plasma levels: relationship with bone mineral density in perimenopausal women.

Bone tissue is a source of growth factors; among them, insulinlike growth factor I (IGF-I) is probably an important local regulator of bone formation. This study has been carried out in order to assess the effects of natural menopause on plasma concentrations of IGF-I in the first 6 years after the cessation of gonadal function independent of age. We also examined the relationship between plasma IGF-I levels and bone mineral density (BMD) measured at the lumbar spine (LS), at the ultradistal radius (UDR), and at the junction of the distal and middle thirds of the radius (MR). Sixty-seven healthy nonobese women, aged 45-55, were studied (premenopausal n = 21; postmenopausal n = 46, from 1 to 6 years since menopause). Plasma IGF-I levels were measured by RIA, after acid-ethanol extraction. BMD of the forearm was measured by dual-photon densitometer and BMD of the LS was assessed by quantitative digital radiography. Mean values of IGF-I plasma levels were significantly reduced in postmenopausal women compared to the premenopausal group. Menopausal duration did not influence IGF-I plasma levels in postmenopausal women. We also found a positive correlation between IGF-I levels and BMD measured at MR both in pre- and postmenopausal women, while a correlation with LS and UDR-BMD was found only in fertile subjects. The results show that IGF-I plasma levels decrease immediately after menopause, since significantly lower levels are reached in the first years. The correlations found between plasma IGF-I levels and BMD suggest a possible role of reduced IGF-I in bone loss at particular skeletal sites.

Aging↗
PubMed1993

Trabecular bone mineral density in primary hyperparathyroidism: relationship to clinical presentation and biomarkers of skeletal turnover.

This study was carried out in order to investigate the entity of trabecular bone involvement in 62 patients with primary hyperparathyroidism (PHPT). Bone mineral density (BMD) was measured in all patients at the ultradistal radius (UDR) of the non-dominant arm by a dual photon densitometer and also at the lumbar spine (L) in 40 of the patients by means of quantitative dual energy radiography. Mean Z score values of UDR-BMD (-2.4 +/- 0.4) and L-BMD (-3.5 +/- 0.2) in patients with the skeletal variety of the disease (n = 6) were significantly reduced in respect to values of both asymptomatic (n = 31) and kidney stone patients (n = 25). As far as the comparison between the two sites of trabecular bone mass measurement in each hyperparathyroid subgroup of patients was concerned, a significant difference (P < 0.05) was found in patients with skeletal manifestations of the disease. Either serum total alkaline phosphatase activity, or osteocalcin and the 24-h hydroxyproline/creatinine ratio were significantly inversely related to the entity of bone mass evaluated at these two sites. Z score changes following surgery in 14 patients showed a positive trend in 13 of them at L compared to 7 out of 14 at UDR (P < 0.036 by chi square analysis). There was a very good inverse correlation between basal Z score values and the changes following surgery at the L (r = -0.851; P < 0.001) but not at the UDR. Our results demonstrate firstly that, in PHPT skeletal sites with almost similar composition of trabecular bone are differently involved in patients with more severe skeletal damage and that different skeletal sites may be divergently affected by the cessation of parathyroid gland hyperfunction.

Absorptiometry, Photon↗
PubMed1992

Evidence for efficacy of drugs affecting bone metabolism in preventing hip fracture.

OBJECTIVE: To examine the effects of taking drugs affecting bone metabolism on the risk of hip fracture in women aged over 50 years. DESIGN: Retrospective, population based, case-control study by questionnaire. SETTING: 14 centres in six countries in southern Europe. SUBJECTS: 2086 women with hip fracture and 3532 control women matched for age. MAIN OUTCOME MEASURES: Number of drugs affecting bone metabolism taken and length taken for. RESULTS: Women taking drugs affecting bone metabolism had a significantly decreased risk of hip fracture. After adjustment for differences in other risk factors, the relative risk of hip fractures was 0.55 (95% confidence interval 0.31 to 0.85) in women taking oestrogens, 0.75 (0.60 to 0.94) in those taking calcium, and 0.69 (0.51 to 0.92) in those taking calcitonin. The fall in risk was not significant for anabolic steroids (0.6 (0.29 to 1.22)). Neither vitamin D nor fluorides were associated with a significant decrease in the risk of hip fracture. The effect on hip fracture risk increased significantly with increasing duration of exposure (risk ratio 0.8 (0.61 to 1.05) for less than median exposure v 0.66 (0.5 to 0.88) for greater than median exposure). Drugs were equally effective in older and younger women, with the exception of oestrogen. CONCLUSIONS: Oestrogen, calcium, and calcitonins significantly decrease the risk of hip fracture. Short term intervention late in the natural course of osteoporosis may have significant effects on the incidence of hip fracture.

Aged↗
PubMed1992

Effects of ipriflavone on bone remodeling in primary hyperparathyroidism.

The aim of this study was to evaluate the effects of ipriflavone treatment on bone remodeling in primary hyperparathyroidism. Nine patients, 6 females and 3 males (mean +/- SD age 56 +/- 12.5 years) were treated with 1200 mg/day of ipriflavone by oral administration divided in 3 daily doses. All patients were treated for 21 days; in 5 patients treatment was prolonged to 42 days. In all patients the main serum and urinary parameters of bone remodeling were evaluated. The results suggest that ipriflavone affects bone remodeling by inhibiting bone resorption without affecting bone formation. Ipriflavone is, therefore, indicated in the treatment of metabolic bone diseases characterized by a high bone turnover.

Adult↗
PubMed1991

A hospital survey of hypocalcemia and hypophosphatemia in malignancy.

We evaluated the incidence of hypo- versus hypercalcemia and hypo- versus hyperphosphatemia in a survey of 158 patients with malignancy; 55/158 had bone metastases. When serum calcium levels were corrected for albuminemia, the incidence of hypo- and hypercalcemia was respectively 10.8% and 10.1%. Hypophosphatemia was found in 29.7% patients, hyperphosphatemia in 2.5%. The incidence was slightly different in presence of bone metastases. Hypocalcemia and hypophosphatemia prevailed in osteoblastic metastases and hypercalcemia in osteolytic metastases. The incidence of hypocalcemia and hypophosphatemia in malignancy was therefore surprisingly high, even apart from the presence of bone metastases. Both hypo- and hypercalcemia were associated with elevated serum alkaline phosphatase levels. Moreover, a calcium-phosphorus product reduction was observed in osteoblastic metastases, suggesting a condition of secondary hyperparathyroidism.

Aged↗
PubMed1990

The effects of oophorectomy on skeletal metabolism.

The effects of oophorectomy on the biological indices of bone remodelling and the time-course of their changes are described. In the first few months following surgical menopause the measurement of the markers of bone remodelling indicates that the increase in osteogenesis is delayed compared with that of bone resorption; this prevalence of destruction over new bone deposition justifies the deficiency of skeletal balance, shortly after acute oestrogen deficiency. The changes in bone remodelling are accompanied by an increase in serum calcium while serum immunoreactive parathyroid hormone levels remain unchanged or even decrease, suggesting a shift to right of the parathyroid gland set-point. The reasons for the negative skeletal balance after oophorectomy might be sought therefore at bone tissue level, even if changes in responsiveness and/or of the parathyroid gland set-point could also be contributory.

Bone and Bones↗
PubMed1990

Two-site assay of intact parathyroid hormone in primary hyperparathyroidism: studies in basal conditions, following adenoma removal and during calcium and EDTA infusion.

This study has been carried out in order to investigate parathyroid hormone secretion in patients with primary hyperparathyroidism in basal conditions, during stimulation and suppression tests and following successful surgery. Parathyroid gland secretory activity has been evaluated by a highly sensitive immunoradiometric assay (IRMA) which detects only the biologically intact active hormone and with a well established midmolecule (MM) PTH RIA. There was a good correlation between the two assays in basal state (r = 0.779); however the correlation found between serum PTH levels and total calcium values was better for the intact hormone (P less than 0.001) than for the radioimmunoassay (P less than 0.05). Twenty-four hours following surgery, serum intact PTH levels were in all patients less than 10 pg/ml while midmolecule PTH was still detectable, thereafter remaining at a higher level during the next six days. Serum IRMA PTH levels fell rapidly in response to the increase in serum calcium, then there was a trend to reach a plateau; serum midregion PTH levels fell, although slower than those of intact hormone. The percent increase obtained for serum intact hormone levels was higher than that observed for MM RIA, following EDTA stimulation. The results obtained indicate that the assays of intact and midmolecule parathyroid hormone clearly reflect different aspects of hormone metabolism 'in vivo' and may prove therefore to be useful for its investigation in various calcium disorders.

Adenoma↗
PubMed1989

Studies on citrate metabolism in normal subjects and kidney stone patients.

The study was carried out in order to investigate citrate metabolism (i.e. serum levels, filtered load, tubular reabsorption, total and fasting urinary excretion) in a large group of normal subjects (n = 39) and kidney stone patients (n = 45). We found that mean serum citrate levels and filtered loads were similar in the two groups studied. On the other hand, both the 24-hour urinary citrate and the fasting citrate/creatinine ratio were significantly reduced, whereas the mean tubular reabsorption of citrate appeared to be significantly increased in kidney stone patients in respect to control subjects. A good correlation was found between the fasting and the 24-hour citrate/creatinine ratio in both normal subjects (r = 0.84, p less than 0.001) and kidney stone patients (r = 0.89, p less than 0.001). Our data indicate that the kidney appears to be involved in the pathogenesis of hypocitraturia in kidney stone patients and that a substantial proportion of these patients show a reduced urinary excretion of citrate. Finally, the evaluation of the fasting citrate/creatinine ratio may replace the measurement of the substance on the basis of a 24-hour urine collection.

Adolescent↗
PubMed1988

Serum osteocalcin in primary hyperparathyroidism: short-term effect of surgery.

This study has been carried out in order to evaluate both serum osteocalcin levels in primary hyperparathyroidism and their changes following surgery. Twenty-one consecutive patients were studied (12 females and 9 males, aged 46 +/- 17 years). Preoperatively, a better correlation was found between serum osteocalcin and serum alkaline phosphatase activity (r = 0.79, p less than 0.001) than between serum osteocalcin and the 24-hour urinary hydroxyproline/creatine ratio (r = 0.55, p less than 0.05). Following the surgical removal of hyperfunctioning parathyroid tissue, a modest but significant decrease was observed in the serum levels of osteocalcin; this reached a nadir during the 1st or 2nd day after the removal of the adenoma. The mean levels then tended to rise, so that the values measured on the 7th day after parathyroidectomy (12.4 +/- 2.5 ng/ml) were not significantly different in respect to basal values (13.6 +/- 2.7 ng/ml). A parallel pattern was also noted as concerns the serum alkaline phosphatase activity. On the contrary, mean values of serum immunoreactive parathyroid hormone (243 +/- 78 vs. 58 +/- 11 pmol/l; p less than 0.02) and serum calcium (12.4 +/- 0.5 vs. 9.2 +/- 0.3 mg/dl; p less than 0.01) were significantly reduced and mean values of serum phosphorus (2.4 +/- 0.2 vs. 3.1 +/- 0.2 mg/dl; p less than 0.001) significantly higher in comparison to basal values.(ABSTRACT TRUNCATED AT 250 WORDS)

1-Carboxyglutamic Acid↗