PubMed Health⌕ Search

Biomedical subjects

L Denti

Publications and source records attributed to L Denti.

34 records · Page 2Linked to original sources
PubMed1989

Obstacles to integrating disabled students in a "two-roof" elementary school.

This article describes a 5-year effort to integrate special and regular students on a campus where special and regular education students are housed in separate but adjacent facilities with separate administrators. Observational data and questionnaires revealed almost total segregation at the end of 3 years. An intensive intervention program, Project L.E.A.D., generated promising short-term movement toward integration, but there were few enduring effects. Physical, social, and psychological barriers created by the two-roof school erect almost insurmountable obstacles to integration. Future efforts should concentrate on building one-roof schools with a single facility and administration.

Adolescent↗
PubMed1989

Calcitonin inhibition of growth hormone-releasing hormone-induced GH secretion in normal men.

Calcitonin has been shown to modulate pituitary hormone secretion in a variety of ways. In this study we examined the effects of a salmon calcitonin infusion on GHRH-induced GH secretion in 5 normal men. In addition, in vitro experiments were performed using primary cultures of rat anterior pituitary cells in order to examine whether there is a direct pituitary effect of CT. Infusion of CT significantly blunted the GH response to GHRH in all subjects without affecting basal GH secretion or plasma calcium levels. Infusion of CT was accompanied by significant increases in ACTH, beta-endorphin, cortisol and free fatty acid levels, and by a significant decrease in serum insulin levels. The addition of CT to primary cultures of rat pituitary cells did not alter basal or stimulated secretion of GH or ACTH. These results indicate that: 1) CT blunts the GH response to GHRH; 2) CT infusion results in the stimulation of the hypothalamic-pituitary-adrenal axis, and 3) this effect is probably exerted at the hypothalamic level, since no direct activity of CT was documented in vitro on either GH or ACTH secretion.

Adrenocorticotropic Hormone↗
PubMed1987

The effects of ACTH 1-17 on GH secretion in vitro.

Recently we demonstrated that ACTH 1-17 infusion in normal subjects is able to stimulate growth hormone (GH) secretion. In order to study the mechanism by which ACTH 1-17 induces this hormonal secretory pattern, we examined the effects of ACTH 1-17 addition to primary cultures of rat anterior pituitary cells and of two human pituitary adenomas (a mixed GH- and PRL-secreting adenoma and a prolactinoma) on GH and PRL secretion. Normal rat pituitary cells responded to rGRF with a dose-dependent increase of rGH: ACTH 1-17 induced a slight not significant increase of rGH secretion even at micromolar concentrations. Furthermore no additive effect of ACTH 1-17 on rGRF-stimulated GH release was observed. No significant stimulatory effect was also documented in the human tumors studied. These results suggest that the GH releasing activity of ACTH 1-17 observed in vivo is mediated via a direct action on CNS.

Adenoma↗
PubMed1987

Cross reactions in radioimmunoassay: a mathematical model for correcting assay results, as exemplified by eliminating the interference of intact thyrotropin in an assay of its beta subunit.

To correct the results of a radioimmunoassay for beta-thyrotropin (TSH) subunit by eliminating the proportion ascribable to intact TSH, we have devised a method that experimentally reproduces the conditions under which the interference develops. Beta-TSH subunit was assayed in several preparations containing known concentrations of both beta-TSH and TSH. The TSH-induced overestimation of beta-TSH was linearly related to the concentration of antigen in the sample. At a constant concentration of TSH, therefore, the following equation is applicable: F = aE + b, where F is the measured (but overestimated) concentration of beta-TSH, E is the actual concentration of beta-TSH, and a and b are the slope and the intercept of the regression line, respectively. a and b, once expressed as a function of TSH, allow the correction of the overestimation. The analysis of the results according to the mass action and conservation laws shows that the antiserum is more avid for the interferent (intact TSH) than for the antigen (beta-TSH).

False Positive Reactions↗
PubMed1986

ACTH 1-17 stimulates GH pituitary secretion in humans.

Nineteen normal subjects (12 men and 7 women) were injected with 100 micrograms of ACTH 1-17. Additionally 6 male subjects were studied twice at 3-day intervals with random infusions of ACTH 1-17 and saline. A clear GH response to ACTH 1-17 infusions (GH peak higher than 5 ng/ml) was documented in 10 out of 12 males and in 6 out of 7 women. In the 6 male subjects studied twice, clear-cut GH increments were observed only after peptide administration. PRL levels decreased throughout the study period both in male and female subjects; however, when the PRL percentage decline was evaluated in the same group of subjects after saline and ACTH 1-17, the more obvious decrease of PRL levels after the peptide infusion was not statistically significant. No variation of LH, FSH and TSH levels was documented. With the exception of the specific increase of cortisol levels, no significant change in peripheral steroid pattern (Te, E2, DHEA-S) was observed. In this experiment the effect on GH secretion was quite evident in both sexes. This effect was obtained using the lowest dosage of ACTH preparation documented in the literature.

Adrenocorticotropic Hormone↗
PubMed1986

[Minimal carcinoma of the breast].

For many years pathologists have argued about the definition and the biologic reasons of what is "early", "minimal" and "occult" breast cancer. Whether these terms really identify entities which today can be meaningful to clinicians and whether the prognostic significance of breast cancer measuring 1 cm or less in diameter should have implications in the treatment decision making will form the subject of this review.

Breast Neoplasms↗
PubMed1984

Acute infusion of hCG and thyroid hormone pattern before and after bilateral orchiectomy.

An acute infusion of 5000 IU of hCG was given to a group of 10 elderly men affected by prostatic carcinoma prior to and 1 month after castration to evaluate the possibility of any aspecific effect on thyroid hormones. No significant change was documented for TT4 and TT3, and a significant increase in fT4 occurred only in the presurgical experiment. From these results the authors conclude that the thyroid movement documented may be correlated to the decreased binding capacity of thyroxine-binding globulins promoted by the increase in Te levels.

Aged↗
PubMed1983

[Value of angiography and echotomography in injuries of the spleen].

In all the patients was performed angiography, while only 11 were studied by the means of Abdominal Ultrasonography. The Authors' aim is to evaluate the accuracy of these two methods and to define a correct diagnostic procedure. The results obtained with Angiography were 15 correct diagnosis and 1 false positive, whereas those obtained with Sonography were 7 correct diagnosis, 2 indicative diagnosis and 2 false negative. Therefore, when a patient is clinically suspected of having a traumatic spleen injury, the Authors suggest to perform an Abdominal Sonography at first. In case of evident spleen lesion, laparatomy will be directly carried out. However, if the sonographic result is negative or aspecific, it will be necessary for the patient to undergo Angiography in order to rule out possible false negative or establish the origin of endoabdominal bleeding correctly.

Angiography↗
PubMedDate not supplied

The role of overweight and glucose tolerance in the impaired pituitary-gonadal axis of obese males.

In a group of 30 obese male patients (160.2% of ideal body weight), an impaired function of the pituitary-gonadal axis has been demonstrated. Decreased testosterone and increased estradiol basal levels, increased LH and FHS responsiveness to gonadotropin-releasing hormone, and increased basal prolactin (PRL) levels are the most significant findings. The overweight factor seems to account for the documented decreased testosterone and increased estrogen levels through a modulation of peripheral steroid metabolism. These peripheral steroid patterns might affect gonadotropin and PRL secretions as well; nevertheless an interference with the metabolism of cerebral neurotransmitters, perhaps related to a nutritional component (impaired glucose tolerance), cannot be completely excluded.

Adult↗
PubMedDate not supplied

Gonadotropin secretion in hyperthyroidism and hypothyroidism.

Gonadotropin patterns were evaluated in a group of 70 patients of both sexes with Graves' disease or primary hypothyroidism. Significant variations were found only in hyperthyroidism where increased basal and stimulated values of both gonadotropins, but particularly LH, occurred. Qualitative and quantitative recovery was seen when euthyroid states were achieved after treatment of hyper- and hypothyroid patients. Interactions with gonadotropin behavior were found in both sexes and in women of different ages. Direct interference on the hypothalamo-pituitary system rather than through the modulation of peripheral estrogen metabolism is suggested as the possible pathogenetic mechanism.

Adult↗