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C Valtorta

Publications and source records attributed to C Valtorta.

18 recordsLinked to original sources
PubMed2006

Prenatal diagnosis of a de novo complex chromosome rearrangement (CCR) mediated by six breakpoints, and a review of 20 prenatally ascertained CCRs.

OBJECTIVES: To describe the cytogenetic and FISH characterization of a prenatally diagnosed de novo complex chromosome rearrangement (CCR), showing the involvement of four chromosomes and six breakpoints, and review the literature concerning prenatally detected CCRs in order to obtain insights into addressing karyotype-phenotype correlations in prenatal genetic counseling. METHODS: Conventional protocols were used to set up cultures and chromosome preparations. Commercial and homemade probes were used for the FISH analyses. RESULTS: An apparently balanced de novo t(4;10;20) was prenatally identified by means of cytogenetic analysis. FISH revealed a rearrangement mediated by six breakpoints and the insertion of chromosome 8 material within the 4q region. The pregnancy was interrupted. The fetus showed malformations and anomalous cortical neuron migration. The assembled list of 20 prenatally detected CCRs points to the preferential involvement of chromosomes 4, 6 and 14. The involvement of chromosome 20 is described here for the first time. CONCLUSIONS: FISH analysis is essential for the accurate definition of a complex rearrangement. Phenotype description of fetuses carrying CCRs investigated by means of molecular cytogenetic techniques may contribute to improving and personalizing genetic counseling in prenatal diagnosis.

Abnormalities, Multiple↗
PubMed1997

Prognostic value of dobutamine echocardiography early after uncomplicated acute myocardial infarction: a comparison with exercise electrocardiography.

OBJECTIVES: This study sought to assess the relative prognostic power of dobutamine echocardiography and exercise electrocardiography after acute myocardial infarction. BACKGROUND: The prognostic value of dobutamine echocardiography early after acute myocardial infarction has not yet been reported. METHODS: One hundred seventy-eight patients (mean age 58 +/- 9 years) with a first uncomplicated acute myocardial infarction underwent predischarge dobutamine echocardiography (5 to 40 micrograms/kg body weight per min, plus atropine if needed) and symptom-limited bicycle exercise electrocardiography and were followed up for 17 +/- 13 months. Stress-induced dyssynergy and ST segment depression > 1 mm were considered criteria of positivity for dobutamine echocardiography and exercise electrocardiography, respectively. RESULTS: Dobutamine echocardiography was positive in 83 patients and exercise electrocardiography in 60. At follow-up there were 5 deaths, 6 nonfatal myocardial infarctions (11 hard events) and 20 cases of unstable angina. Dobutamine echocardiography and exercise electrocardiography had similar negative predictive values both for all events (88% and 86%, respectively) and for hard events (98% and 95%, respectively). The hard events rate was significantly higher in patients with positive rather than negative dobutamine echocardiography (relative risk [RR] 5.15, 95% confidence interval [CI] 1.14 to 23.16), although there was no difference between patients with positive and negative exercise electrocardiograms. When Cox analysis was performed, dobutamine echocardiography had an independent prognostic value both for all events (RR 2.88, 95% CI 1.37 to 6.08) and for hard events (RR 6.56, 95% CI 1.42 to 30.46). CONCLUSIONS: After uncomplicated acute myocardial infarction, dobutamine echocardiography and exercise electrocardiography have a similar high negative predictive value for both all events and hard events only. Positive dobutamine echocardiography, but not positive exercise electrocardiography, identifies a group of patients at higher risk of subsequent cardiac events.

Aged↗
PubMed1997

[Prognostic stratification after acute uncomplicated myocardial infarction: exercise test, echo-dobutamine test or both?].

OBJECTIVES: The aims of this study were: 1) to assess the relative prognostic value of predischarge dobutamine echocardiography (DE) and exercise electrocardiography (EE) in patients after a first uncomplicated acute myocardial infarction (AMI), and 2) to evaluate the optimal prognostic strategy by using the two tests in different combinations. METHODS: DE (dobutamine infusion 5 to 40 micrograms/kg/min plus atropine 0.25 to 1 mg, if needed) and symptom-limited bicycle EE were performed in 208 patients (mean age 58 +/- 9 years, 90% males), on different days and in random order, 12 +/- 4 days after a first uncomplicated AMI and after pharmacological washout. A stress-induced dyssynergy and ST segment depression > 1 mm were considered criteria of positivity for DE and EE, respectively. Only spontaneous cardiac events were considered: cardiac death, reinfarction (= hard events), and unstable angina requiring hospitalization (= soft events). RESULTS: Thirty-eight events occurred during follow-up (16 +/- 13 months; range: 1-44 months); 5 cardiac deaths, 6 reinfarctions and 27 unstable angina. Patients with a positive DE had a twofold increase in all event rates (26 vs 12%, p < 0.01) and a fourfold increase in the rate of hard events (9 vs 2%, p < 0.05). In contrast, no statistically significant difference was observed in the distribution of the same events between patients with positive and negative EE. Both tests showed similar negative (DE 88%, EE 85%) and positive (DE 26%, EE 24%) predictive values. Among six different strategies (performing either DE or EE only in all patients; EE in all patients; EE in all patients and DE only in those with a positive EE; and DE only in those with a negative EE; EE in all patients and DE only in those with anterior AMI), EE only in patients with inferior or non-Q AMI and DE only in those with anterior AMI), performing DE only in patients with a positive EE gave the highest predictive accuracy-74% (95% confidence intervals 68 to 80) for all events and 77% (95% confidence intervals 71 to 83) for hard events. CONCLUSIONS: In patients with a first uncomplicated AMI, DE is useful in identifying patients at high and low risk of future spontaneous cardiac events. The optimal strategy for prognostication of these patients is to perform EE in all and DE only in the ones with a positive EE.

Acute Disease↗
PubMed1990

Effects of salmon calcitonin on the bone loss induced by ovariectomy.

We present the results of a 12-month clinical study assessing the effects of synthetic salmon calcitonin (sCT) on a group of fertile white women who had undergone ovariectomy for uterine fibromatosis. The study was performed to verify whether CT can prevent the loss of bone mass and the changes in calcium-phosphorus metabolism associated with acute estrogen deficiency. The study consisted of an initial double-blind phase of 6 months, followed by a 6-month open period. Treated patients were given 100 MRC U of synthetic salmon CT injected i.m. in the morning, every other day, starting on the 7th day after the operation and continued for 12 months. Control patients received a placebo injection for the first 6 months; subsequently, they too were treated with sCT i.m. every other day for 6 months at the same dose as the 12 month-treated group. All patients received 500 mg of elementary calcium p.o., b.i.d. Bone mineral content (BMC) was measured at the extreme distal radius of the nondominant arm by a dual photon bone densitometer which utilizes two radio nuclides, 241 Am and 125 I, with energies of about 60 and 30 KeV. Biochemical parameters of the calcium-phosphorus metabolism were also measured. After 12 months of study, no significant changes of BMC were observed in the 12 months sCT treated group, while control patients, treated 6 months after the ovariectomy, showed a significant decrease in BMC values.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
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↗
PubMed1987

Recurrent hyperparathyroidism: a study of 3 cases with evaluation of some pathogenetic and clinical aspects.

Three patients with recurrent hyperparathyroidism (15, 8 and 3 years respectively, after the first operation) are described in order to establish the causes and define the clinical characteristics of the disease. The observation that in the present series recurrent hyperparathyroidism was associated either with an adenoma (two cases) or a carcinoma (one case), appears to stress the possibility of the pathological involvement of one gland even though recurrent hyperparathyroidism should be considered due to the chronic extrinsic stimulation of the parathyroid glands. The severity of the clinical and metabolic picture observed at the time of the first diagnosis and/or at the time of recurrence together with the simultaneous presence of bone and stone disease in the patients described is of particular interest. The cases reported underline the importance of carrying out careful metabolic investigations in patients with hyperparathyroidism not only before but also for a prolonged period of time after operation.

Adenoma↗
PubMed1987

Normal calcitonin secretion in acromegaly.

Calcium and phosphate metabolism has been studied in eight patients with active acromegaly. Plasma calcium, phosphate, alkaline phosphatase, creatinine and parathyroid hormone levels were in the normal range in all patients, while urinary calcium excretion, calcium/creatinine ratio and hydroxyproline were higher than in controls (p less than 0.01, p less than 0.01, p less than 0.02, respectively). Basal plasma calcitonin levels were in the normal range and stimulation with calcium (3 mg/kg body weight in 10 min) showed similar calcitonin responses in acromegalic and normal subjects. Our data show that in normocalcemic acromegaly with high bone turnover calcitonin secretion is not abnormal.

Acromegaly↗
PubMed1986

Effects of salmon calcitonin in postmenopausal osteoporosis: a controlled double-blind clinical study.

In this paper we present the results of a 12-month double-blind clinical multicenter study assessing the effects of synthetic salmon calcitonin (CT) administration in a group of white postmenopausal osteoporotic women. Treated patients were given 100 MRC units of synthetic salmon CT injected i.m. in the morning every other day. Control patients received a placebo injection. All patients received 500 mg of elementary calcium p.o., b.i.d. Bone mineral content (BMC) was measured at the extreme distal radius of the nondominant arm by a dual photon bone densitometer which utilizes two radionuclides, 241Am and 125I, with energies of about 60 keV and 30 keV respectively. Biochemical parameters of calcium-phosphorus metabolism were also measured. After 12 months of treatment a significant mean increment of BMC and nondialyzable OHPr/creatinine values and a significant decrease of total OHPr/creatinine values were observed in the treated group, while controls showed a significant decrease in BMC values. These results, together with the observation that in some patients the decrease in total OHPr/creatinine values was not accompanied by an increment of BMC, show that long-term salmon CT treatment may be of benefit in postmenopausal osteoporosis and that the effects of CT on bone mass may be due not only to the inhibition of bone resorption but also to the stimulation of bone formation.

Aged↗
PubMed1986

Basal and stimulated calcitonin secretion in primary hyperparathyroidism before and after parathyroidectomy.

To investigate calcitonin secretion in primary hyperparathyroidism, basal and stimulated (3 mg Ca++/kg body weight/10 min) immunoreactive calcitonin plasma levels were studied before parathyroidectomy. Plasma calcitonin levels were raised in 50% of patients regardless of sex, but a significant correlation between basal plasma calcium and calcitonin was found only in males. A reduced calcitonin response to calcium infusion was observed in all patients. Parathyroidectomy invariably induced a normalization of calcitonin basal levels. Our findings confirm the existence of a decreased parafollicular cell reserve probably as a consequence of the persistent hypercalcemic state in hyperparathyroid patients and suggest that it is more frequent in females.

Adult↗
PubMed1985

Pathophysiological studies in hypercalciuric and normocalciuric stone formers.

This study has been carried out in order to investigate the effects of a standard oral calcium load in 18 hypercalciuric and 18 normocalciuric recurrent stone formers. Following oral loading there was not a significant difference in the two groups studied, as far as serum calcium increment was concerned; however, urinary calcium excretion was significantly greater in hypercalciuric stone formers. The results obtained, although they do not exclude the presence of intestinal calcium hyperabsorption, seem to demonstrate the existence of a diminution of renal tubular calcium reabsorption in patients with idiopathic hypercalciuria.

Administration, Oral↗
PubMed1985

Changes in mineral content and biochemical bone markers at the menopause.

Serum alkaline phosphatase activity, serum bone gamma-carboxyglutamic acid protein, urinary hydroxyproline and bone mineral content were simultaneously measured in 30 age-matched pre- and postmenopausal women in order to define the temporal relationship between skeletal turnover and bone loss. In postmenopausal women, mean values of phosphatase activity, serum bone gamma-carboxyglutamic acid protein and urinary hydroxyproline were significantly higher, and mean values of mineral content were significantly lower than in premenopausal women. A marked loss of bone mineral content together with a persistent increase in skeletal turnover is already evident shortly after the menopause.

1-Carboxyglutamic Acid↗
PubMed1984

Acute effects of removal of parathyroid adenoma on plasma and urinary hydroxyproline levels.

This study was carried out to investigate early effects of parathyroidectomy (PTx) on bone matrix collagen metabolism. Eleven patients suffering from primary hyperparathyroidism were studied by measuring urinary excretion of hydroxyproline (OHPr) and cAMP in samples collected before PTx and, on the day of surgery, at intervals of 1-3 h for the first 10 h and then at longer intervals. In six patients nondialyzable urinary OHPr and free plasma aminoacid levels were also assayed. We found that the average period required for OHPr/Cr ratio and plasma OHPr to reach normal values was longer than the mean time required for cAMP/Cr ratio to reach normal limits. In all patients the total amount of nondialyzable OHPr decreased in the first 24 h after PTx but thereafter a daily increase in the urinary excretion of nondialyzable component was seen, so that the fractional amount of nondialyzable OHPr in the fourth postoperative day (26.8 +/- 5.2 SE) was significantly higher than that of preoperative one (6.1 +/- 1.0; p less than 0.02). Our results confirm that PTx induces a reduction in the rate of bone collagen resorption and indicate that changes of OHPr/Cr ratio and free plasma OHPr values may be considered useful indices of successful parathyroid surgery, even though they lag behind those of cAMP. The different behavior of total and nondialyzable OHPr after surgery indicates that acute deficiency of parathyroid hormone induces a positive uncoupling of the two processes of bone remodeling, thus supporting the view that the acute direct effect of the hormone on bone formation is an inhibition of this process.

Adenoma↗
PubMed1983

[Influence of age and sex on the urinary excretion of total and non-dializable hydroxyproline].

Urinary excretion of total OHPr, an index of bone resorption, was evaluated in 68 normal subjects (25 males and 43 females) aged 19-83 years. In 49 of them non-dialyzable OHPr(ndOHPr), which reflects bone matrix formation, was also determined. Total urinary OHPr, expressed as mg/24 h, significantly decreased with advancing age in both sexes: however by means of multiple regression analysis no correlation was found after correction of OHPr behaviour for changes in creatinine clearance. On the contrary ndOHPr was inversely correlated with age (r = -0,56, p less than 0,001) even when creatinine clearance was held constant (p less than 0,05). The findings obtained seem to show that a decrease in osteogenetic activity is also responsible for the physiological ageing bone loss.

Adult↗
PubMed1983

Plasma calcitonin and tumors.

Plasma levels of calcium, phosphorus, immunoreactive calcitonin (iCT), immunoreactive parathyroid hormone (iPTH), and carcinoembryonic antigen (CEA) were measured in patients affected by tumors of various organs: 22 breast, 41 lung, 23 kidney, 16 gastrointestinal tract, and 8 other types, iCT plasma level was elevated in 53.6% of patients with bronchogenic cancer, in 31.8% with breast cancer, in 65.3% with renal cancer, in 31.2% with gastrointestinal cancer, and in 62.5% with other tumors. Blood calcium level was increased in 6 patients suffering from lung cancer; iCT plasma level was increased in all but one of these subjects. iPTH plasma level, measured in 35 patients, was elevated only in one case, in which normo-calcemia was present. Our results demonstrate that plasma iCT is increased in a high percentage of cancer patients and that it is probably a good tumor marker. The simultaneous measurement of CEA increases the diagnostic probability of the individual marker. The incidence of laboratory findings suggestive of primary or ectopic hyperparathyroidism was very low in our series of patients.

Blood Proteins↗
PubMed1981

Calcitonin secretion and bone disease severity in hypercalcaemic hyperparathyroidism.

Calcitonin (CT) plasma levels and urinary hydroxyproline (OHPr) excretion were studied in twenty-eight patients (eleven males and seventeen females) with primary hyperparathyroidism in order to ascertain the effect of CT secretion on the severity of bone disease. The results show that in primary hyperparathyroidism plasma CT levels are increased in about 50% of patients independent of sex. Plasma CT levels were correlated with serum calcium values in males but not in females. Urinary OHPr excretion values appeared higher in those patients which showed lower CT plasma levels. In this latter group the incidence of undetectable CT plasma values was higher in females. The results suggest that in patients with primary hyperparathyroidism the persistent challenge of CT secreting parafollicular cells due to chronic hypercalcemia, may induce a decrease in their functional reserve, and that the bone involvement may have a greater incidence and more severe course in females, due at least in part, for their inability to increase CT secretion as much as males, due to an intrinsic sex-related lower CT secretory reserve.

Adolescent↗
PubMedDate not supplied

Effects of age on the urinary excretion of total and non-dialyzable hydroxyproline.

This study was carried out in order to investigate the effects of age on the urinary excretion of total and non-dialyzable hydroxyproline (OHPr) in normal subjects. We found that total urinary OHPr was negatively correlated with age but, by means of partial regression analysis, no correlation was found after correction for changes in creatinine clearance; on the contrary, non-dialyzable OHPr showed a statistically significant negative correlation with age (r = -0.56) even when creatinine clearance was held constant (p less than 0.05). A highly significant direct correlation was found between total and non-dialyzable OHPr in the whole group (r = 0.54) and when only premenopausal women and men under 60 years of age were considered (r = 0.51). No correlation was found when postmenopausal women and men more than 60-year-old were taken into account. Our data appear to indicate that also the decrease in osteogenetic activity is responsible for the physiological late involutional bone loss; they also show the importance of hormonal changes in inducing an uncoupling between bone formation and resorption.

Adult↗