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R Valenti

Publications and source records attributed to R Valenti.

8 recordsLinked to original sources

Metabolic effects of rectal administration of unmodified eel calcitonin in humans.

To evaluate the metabolic effects of unmodified eel calcitonin, nine normal subjects and eleven patients with Paget's disease of the bone entered the study. Eel calcitonin was administered via rectal mucosa at the dosage of 100 and 200 MRCU. Plasma calcium, plasma phosphate and plasma cAMP were measured at a baseline and after 10, 20, 30, 60, 90, 120, 180, 240 min. Rectal administration of 100 MRCU of eel calcitonin decreased plasma calcium and phosphate levels in normal subjects; the hypocalcaemic and hypophosphatemic effects were more marked and statistically significant in Paget's disease patients. Using 200 MRCU of eel calcitonin, statistically significant reductions in plasma calcium levels were observed in controls and in Paget's disease patients. Plasma phosphate decreased after rectal administration of the hormone, but not significantly. A slight but not significant increase in plasma cAMP was observed in normal subjects after the administration of 200 MRCU. These data demonstrate that eel calcitonin administered via rectal mucosa can exert some of the known biologic effects of the peptide.

Administration, Rectal

[An autopsy study of patients who died at the Medical Clinic of the University of Siena from 1986 to 1989].

In the past twenty years autopsies are performed much less frequently in the elderly than in younger patients. The clinical diagnostic error rate documented by autopsy studies ranges from 6% to 68%. We analyzed the clinical and autopsy records of 214 patients who died from 1 January 1986 to 31 December 1989 at our Institute to determine the accuracy of clinical cause of death with respect to the pathologic cause of death. The most common cause of death were bronchopneumonia (25.2%) followed by gastroenteric and lung cancer (20%), cerebrovascular accident (15.8%), myocardial infarction (8%) and pulmonary embolism (7.4%). Pulmonary embolism was correctly classified only in 25% of patients. The most accurately diagnosed condition were neoplastic diseases (88%) and cerebrovascular accident (84.8%) while bronchopneumonia were correctly diagnosed antemortem in 72.2% of the patients studied. Our data suggest that advances in diagnostic technology have not reduced the value of the autopsy and that a goal-directed autopsy remains a vital component in the assurance of good medical care.

Age Factors

[Methodological basis and clinical applications of total-body densitometry].

With the advent of dual-energy x-ray absorptiometry (DXA) total body scans can be done in only 10-20 minutes rather than the 60-80 minutes required by dual-photon absorptiometry (DPA). The DXA approach replace the Gd153 radionuclide source of DPA and provides substantially greater output intensity. The higher radiation flux achievable provides several advantages over conventional DPA: this makes total body scans routinely accessible. The measures of the entire skeleton and its major subregions cut down the problems of representativeness and relocation. The short term precision (coefficient of variation) was 0.5% for total body-bone mineral density (BMD) and about 1% for regional-BMD. We studied 885 women; study cohort consisted of 161 healthy postmenopausal women, 357 healthy postmenopausal women and 367 osteoporotic women with one or more vertebral crushes. The results indicate that bone mass begin decreasing during the last period of the premenopausal phase; the advent of menopause brings about a dramatic reduction of both total body and single area BMD: this phenomenon is particularly marked in subjects with osteoporosis. The single most important factor in determining BMD changes, is years since menopause. In order to assess the ability of DXA total body to distinguish women with postmenopausal osteoporosis of variable radiological degress from healthy postmenopausal women, we studied 330 postmenopausal females aged 42-85 years. There were 63 healthy women who were considered controls (Group 1).(ABSTRACT TRUNCATED AT 250 WORDS)

Absorptiometry, Photon