PubMed Health⌕ Search

Biomedical subjects

T Torresani

Publications and source records attributed to T Torresani.

11 recordsLinked to original sources
PubMed1992

Comparison between short- and long-term insulin-like growth factor response to recombinant human growth hormone.

Eight growth-hormone-deficient children were treated with recombinant human GH (rhGH). Results of the short-term metabolic response to rhGH performed at the start of therapy during a 5-day introduction period and long-term results on growth were analyzed. We could not find any correlation between the effects on the short-term metabolic test and the growth response during long-term therapy, namely between the urea and insulin-like growth factor-I response during the short test and the increase in growth velocity. The short-term test is not a good predictor of the long-term response.

Adolescent↗
PubMed1991

Recombinant human insulin-like growth factor I (rhIGF I) reduces hyperglycaemia in patients with extreme insulin resistance.

The syndrome of type A insulin resistance is encountered in young women and is characterized by glucose intolerance or frank diabetes mellitus, endogenous hyperinsulinism, insensitivity to insulin administration, acanthosis nigricans and virilization. The insulin resistance is due to reduced cellular insulin binding because of a lack of or defective binding sites and/or because the interaction with the tyrosine kinase of the beta-subunit is hindered. This study was undertaken to find out whether hyperglycaemia in these patients may be influenced by the administration of recombinant human insulin-like growth factor I which exerts insulin-like effects through the insulin receptor as well as the type 1 insulin-like growth factor I receptor. Recombinant human insulin-like growth factor I was intravenously administered in two subsequent doses of 100 micrograms/kg body weight to three women with type A insulin resistance. An immediate but slow fall of blood glucose was observed. The glucose disappearance rate was 28.0 mumol/min, i.e. considerably lower than that seen in healthy subjects. The markedly elevated insulin and C-peptide levels fell in a parallel manner to blood glucose but not to normal levels. The results show that recombinant human insulin-like growth factor I, presumably by reacting with the type 1 insulin-like growth factor receptor, can normalize serum glucose levels in patients with severe insulin resistance at least for several hours. We suggest that the potential or recombinant human insulin-like growth factor I to control hyperglycaemia in type A insulin resistant patients should be explored in more depth.

Adolescent↗
PubMed1991

Interest of growth hormone-releasing hormone administration for improvement of ovarian responsiveness to gonadotropins in poor responder women.

OBJECTIVE: We have investigated the beneficial effect of a somatotroph axis stimulation on ovarian response to gonadotropin. DESIGN: Growth hormone-releasing hormone (GH-RH) was administered in a prospective study in women undergoing an in vitro fertilization protocol. PATIENTS: Twelve patients were selected for their poor ovarian response to previous stimulations using gonadotropin-releasing hormone analog (GnRH-a) and human menopausal gonadotropins (hMG). INTERVENTIONS: Five hundred micrograms of GH-RH1-29 were administered two times daily concomitantly with GnRH-a and hMG from day 2 of the cycle to the time of ovulation. MAIN OUTCOME MEASURES: Stimulation of somatotroph axis was appreciated by measuring over-night urinary growth hormone (GH) output, plasma GH, and insulin-like growth factor I (IGF-I) and follicular fluid (FF) IGF-I. The effects of GH-RH administration on ovarian function were determined by plasma estradiol levels and follicular data. RESULTS: Administration of GH-RH was associated with a significant improvement of urinary (P less than 0.025) and plasma (P less than 0.001) GH concentrations and of the hormonal response to hMG (P less than 0.01). Levels of IGF-I followed a biphasic plasma variation, and a slight increase in recruited follicles, retrieved oocytes, and FF IGF-I content was also observed. CONCLUSIONS: Activation of the somatotroph axis by GH-RH enhances the hormonal ovarian response to hMG and may be an adjunctive therapy to improve follicular maturation.

Adult↗
PubMed1991

Serum and follicular fluid insulin like growth factors I and II during growth hormone co-treatment for in-vitro fertilization and embryo transfer.

OBJECTIVE: We wished to assess the changes in serum IGF-I and IGF-II concentrations during gonadotrophin treatment alone or with additional GH treatment and to compare follicular fluid IGF-I and IGF-II concentrations in the two treatment groups. DESIGN: We performed an open study of co-treatment with GH and subsequently a randomized double blind comparison of addition of placebo or GH to clomiphene citrate and gonadotrophins. PATIENTS: We studied previously poor responders to superovulation regimens for in-vitro fertilization and embryo transfer, six women in an open study, four of whom had ultrasound diagnosed polycystic ovaries, and 17 women in a double blind study, 12 of whom had polycystic ovaries. MEASUREMENTS: We measured serum IGF-I and IGF-II concentrations throughout treatment cycles. Follicular fluid concentrations were measured at the time of oocyte recovery. RESULTS: Neither serum IGF-I nor IGF-II concentrations were altered by gonadotrophin treatment alone. However, co-treatment with GH led to a significant rise in serum IGF-I concentrations in women with ultrasound diagnosed polycystic ovaries. Concentrations of IGF-I and IGF-II in follicular fluid were lower than in serum, although follicular fluid IGF-I concentrations were higher in women receiving GH than in those receiving placebo. CONCLUSIONS: Poor responders to superovulation regimens may have an abnormality of growth factor response. GH co-treatment leads to an increase in circulating IGF-I concentrations in women with polycystic ovaries but our results do not support the hypothesis that GH stimulates IGF-I production in the human ovary.

Adult↗
PubMed1979

Changes of serum testosterone and of LH-RH test after treatment of cryptorchidism by intranasal LH-RH.

The aim of the present investigation was to study, in a collaborative double-blind study, the treatment with intranasal LH-RH application of boys aged 1 1/2 to 12 years, who suffered from unilateral or bilateral cryptorchidism. A total of 88 subjects were randomly and blindly allocated to LH-RH and placebo therapy. Before and after 4 weeks of treatment basal testosterone serum levels were estimated and LH-RH tests were performed. Intranasal treatment with LH-RH resulted in partial or complete descents of testes in 23 out of 88 patients, whereas the position of testes remained unchanged in 17 subjects. 42 boys did not respond to placebo therapy, but complete descents were observed in 6 boys of the placebo group. Hormone analysis data of 4 different laboratories were recorded and statistically evaluated. No changes of LH, FSH and testosterone were found in the placebo groups. Only patients of the Frankfurt group responded to LH-RH test with augmented LH release after therapy (P less than 0.05). All patients treated with intranasal LH-RH showed a significant decrease of FSH release after therapy (P less than 0.05 to P less than 0.01). Basal testosterone serum levels were found to be increased after therapy only in the patients treated at Zürich (P less than 0.05). Data of the present study combine to suggest that chronic application of LH-RH may result in an overstimulation phenomenon, and that LH-RH test as well as basal testosterone levels cannot be used as prognostic index of therapy efficacy.

Administration, Intranasal↗
PubMed1977

Early detection of neonatal hypothyroidism by serial TSH determination in dried blood. Six months experience with a reliable, efficient and inexpensive method.

Mass newborn screening for primary hypothyroidism was introduced in Switzerland on January 1st, 1977, using a radioimmunoassay of TSH in dried blood spotted on filter paper. After incubation for 38 h at 20 degrees C, bound and free TSH is separated by double antibody precipitation. The filter paper discs of 6.5 mm diameter remain in the test tubes. At present, one TSH determination costs approx. SFr. 4.40. All reagents used are commercially available and their costs amount to not more than 15% of the total expenses. During the first 8 months of 1977, of 21862 newborns tested routinely on day 5 (together with the Guthrie-test), 7 infants with primary hypothyroidism were discovered owing to blood TSH values of greater than 100 muU/ml. Diagnosis was not recognized clinically although all of the infants showed some symptoms. Thyroxin therapy was started within the second week of life. The incidence of about 1 in 3000 newborns is higher than reported so far. It has to be shown whether this is due to genetic or geographic factors, to the occurrence of transitory forms, or to a higher efficiency of screening by the TSH (versus T4) assay.

Blood Specimen Collection↗
PubMed1976

Gonadal function in young adults after surgical treatment of cryptorchidism.

In a follow-up study of 48 young men who had been surgically treated for cryptorchidism before puberty testicular function was assessed by examining the genitalia, testicular volume, secondary sex characteristics, semen, plasma luteinising hormone (LH) and follicle-stimulating hormone (FSH) concentrations after luteinising hormone-releasing hormone stimulation, and plasma testosterone concentrations. Clinical androgen effects were normal. The mean testicular volume of both testes was in the low normal range in those who had had unilateral cryptorchidism and below normal in those who had had bilateral cryptorchidism. Of 37 patients whose sperm counts were recorded (14 bilateral) six showed azoospermia (all bilateral), five had severe oligospermia (four bilateral), and 10 had moderate oligospermia (one bilateral). In nearly all those who had had bilateral cryptorchidism and most of those who had had unilateral cryptorchidism plasma gonadotrophin levels were increased. Four cases of possible partial LH deficiency were identified. Plasma testosterone concentrations were normal in all except two patients.

Adolescent↗
PubMed1975

The effect of alpha-MSH on plasma growth hormone, cortisol and TSH in children.

The effect of synthetic alpha-MSH injected intravenously in a uniform dose of 3 mg was studied in 19 prepubertal children. A marked growth hormone (GH) response was seen only in 2 out of 8 constitutionally small children with a normal GH response to insulin and arginine stimulation. Three of of 11 children suffering from hypopituitarism with documented GH and other hormone deficiencies, unexpectedly, showed a significant rise of GH after alpha-MSH: all three had craniopharyngiomas. Alpha-MSH led to an increase of plasma cortisol in all except 3 patients who had secondary adrenal insuffciency. The increase of cortisol after alpha-MSH and after insulin was of the same extent: but the hypoglycemia and stress responsible for the insulin effect were not observed after alpha-MSH. It is possible that alpha-MSH acts by an ACTH-like direct stimulation on the adrenals. There was no effect of alpha-MSH on plasma TSH or on blood glucose.

Adolescent↗
PubMed1975

Elevated plasma TSH and hypothyroidism in children with hypothalamic hypopituitarism.

Basal TSH levels were found to be elevated in 6 patients with documented growth hormone deficiency and hypothyroidism. TRH (200 mug/m2 administered intravenously) led to an exaggerated TSH response. This is in contrast to the results in other GH-deficient children, with either a delayed rise of TSH (hypothalamic hypothyroidism due to TRH deficiency, n = 22), an absent TSH response (pituitary hypothyroidism due to TSH deficiency, n = 7), or a normal increase of TSH (isolated GH deficiency, n = 20). Elevated plasma TSH in the presence of hypothyroidism as seen in 6 of our patients with idiopathic hypopituitarism or craniopharyngioma, indicates an intact feedback action between the pituitary and the thyroid gland. TSH, however, seems to be inadequate for the maintenance of normal thyroid function. It is suggested that in certain patients with hypothalamic disorders, TSH is secreted in a biologically less active form.

Adolescent↗