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Biomedical subjects

T Pasqualini

Publications and source records attributed to T Pasqualini.

At least 37 records · Page 2Linked to original sources
PubMed1991

Evidence of hypothalamic-pituitary thyroid abnormalities in children with end-stage renal disease.

Patients with end-stage renal disease may have abnormalities of growth and of gonadal and thyroid hormones, so we attempted to determine the mechanisms that may be involved in the altered thyroid function. We evaluated serum thyroid hormone levels, their changes immediately after hemodialysis, the serum thyrotropin (thyroid-stimulating hormone (TSH) response to thyrotropin releasing hormone, and the circadian pattern of serum TSH in nine children with end-stage renal disease who were between 7 1/2 years and 17 years 1 month of age. Seven patients had been receiving hemodialysis for a median of 3.3 years; the other two were receiving continuous ambulatory peritoneal dialysis. Four patients had low serum total thyroxine (T4) values, and all nine had low free T4 values. Mean concentrations of total T4, free T4, and total triiodothyronine (T3), which were significantly less than normal before hemodialysis, returned to normal levels immediately after dialysis. Postdialysis thyroid hormone increases did not correlate with the decrease in weight or the increase in hematocrit observed immediately after dialysis. All but one patient had basal TSH levels within the normal range. Three patients had a deficient TSH response to thyrotropin releasing hormone, and the TSH response was prolonged in all of them. The mean (+/- SD) nocturnal TSH surge was 50 +/- 68%. Five of the eight patients studied had a nocturnal TSH surge below the normal range (95% confidence limits 47% to 300%). Serum free T4 values correlated with the TSH nocturnal surge (r, 0.73; p less than 0.05). Our findings support the hypothesis that some patients with end-stage renal disease have central hypothyroidism.

Adolescent↗
PubMed1991

Subtle primary hypothyroidism in patients treated for acute lymphoblastic leukemia.

We evaluated serum thyroid hormone and thyroid antibody levels, the serum TSH response to TRH, and the circadian pattern of serum TSH in 10 children and adolescents after radiation therapy for acute lymphoblastic leukemia. Four patients had received central nervous system preventive cranial irradiation and intrathecal chemotherapy, and the remaining 6 patients were treated with craniospinal irradiation for central nervous system relapse. Serum total T4 and T3 concentrations were within the normal range and thyroid antibodies were negative in all patients. Four patients who had received craniospinal irradiation had low free T4 levels. Prior to TRH administration, the overall mean serum TSH concentration was 5.4 +/- 1.3 mU/l, and the mean peak response to TRH was 33 +/- 6.5 mU/l. Both were significantly increased when compared to the levels observed in our control population (p less than 0.05 and less than 0.025, respectively). The overall mean nadir diurnal TSH was 3.6 +/- 0.8 mU/l, and the mean peak nocturnal TSH was 6.9 +/- 1.3 mU/l, both significantly elevated when compared to normal children (p less than 0.025). The mean nocturnal TSH surge, however, was not significantly different from normal. Four of 6 children treated with craniospinal irradiation, and one of four children treated with cranial irradiation had increased basal and peak serum TSH concentrations in response to TRH. One of the patients treated with cranial irradiation had an abnormal nocturnal TSH surge. We conclude that subtle primary hypothyroidism is relatively common in patients with acute lymphoblastic leukemia, particularly in those who have been treated with craniospinal irradiation.

Adolescent↗
PubMed1989

Thyroid dysfunction in Hodgkin's disease.

Radiotherapy to the neck and/or polychemotherapy late effects on the thyroid were investigated in 51 patients (34 males and 17 females) with Hodgkin's disease. Except for two untreated, recently diagnosed patients, all were studied after 1 to 105 months (median, 27.5 months) of completion of polychemotherapy. Age ranged from 6.2 to 36.6 years (median, 13.6 years). Patients were divided according to treatment into four groups: (A) patients treated with CVPP (cyclophosphamide, vinblastine, procarbazine, and prednisone); (B) 22 patients treated with CVPP plus radiotherapy (median radiation dose to the thyroid, 3000 cGy); (C) seven patients with ACOP/BVP (adriamycin, cyclophosphamide, vincristine, prednisone, bleomycin, vinblastine, procarbazine); and (D) seven patients treated with different polychemotherapy protocols, four of whom also received radiotherapy. Elevated basal and/or post-TRH, -TSH levels were found in the following: Group A: two of 12 patients (17%); Group B: 11 of 22 (50%); Group C: four of seven (57%); and Group D: two of seven (28%). Positive antimicrosomal thyroid antibody titers (AM Ab) were found in the following: Group A: three of 12 patients (25%); Group B: six of 21 (28%), Group C: two of seven (28%); and Group D: one of six (17%). Of 46 patients studied, 12 (26%) had positive AM Ab; 37 of 46 patients were younger than 20 years of age, 11 (30%) of whom had positive AM Ab versus 4% in the normal population (P less than 0.001). Two recently diagnosed, untreated patients had either high TSH response to TRH or positive AM Ab. In conclusion, higher frequency of thyroid dysfunction was observed in patients receiving radiotherapy (50% versus 27%). Prevalence of positive AM Ab, apparently unrelated to therapy, was higher in young patients than in the normal population. A predisposition to autoimmune thyroid disease seems to be present in these patients, but it is not possible to discern how lymphoma and thyroiditis are interrelated.

Adolescent↗
PubMed1989

A monoclonal antibody to murine CD45R distinguishes CD4 T cell populations that produce different cytokines.

CD4 T cell clones have been shown to be functionally heterogeneous in the mouse. However, it is not known if normal CD4 T cells are also functionally heterogeneous, or whether functional specialization is a result of cloning and long-term culture. To approach this question, a monoclonal antibody reacting with a subset of CD4 T cells has been prepared by immunization of rats with different cloned T cell lines all sharing the same functional activity. This monoclonal antibody reacts with a subset of CD45 (T200) molecules by binding to a determinant requiring the expression of the second variable exon of the CD45 molecule. Some CD4 T cells bear high levels of this marker, while others react only weakly. This antibody was used to separate CD4 T cells into two subpopulations. The brightly staining population was found to produce interleukin (IL) 2 and not IL 4, while the weakly staining population produced IL 4 and not IL 2. These data demonstrate that CD4 T cells in normal mice are already functionally committed, and that they differentially express forms of CD45 that contain the second variable exon.

Animals↗
PubMed1988

Autocrine growth of CD4+ T cells. Differential effects of IL-1 on helper and inflammatory T cells.

The growth factor requirements of cloned lines representing two major subsets of CD4+ T cells were examined. The helper subset, which produces IL-4 as its autocrine growth factor, proliferates in response to IL-2 or to IL-4 in the presence of IL-1. The inflammatory subset, which produces IL-2 as its autocrine growth factor, proliferates in response to IL-2 and, in the presence of limiting amounts of IL-2, shows increased proliferation in the presence of IL-4. The inflammatory subset does not proliferate in response to IL-1 plus IL-4. This ability to respond to the combination of IL-1 plus IL-4 correlates with the presence of IL-1R on the cloned lines tested. These data suggest that IL-1 may play a controlling role in the clonal expansion of CD4+ T cells of different functional types. This, in turn, suggests means by which the immune response could be directed into humoral or cell-mediated responses.

Animals↗
PubMed1987

Long-term endocrine sequelae after surgery, radiotherapy, and chemotherapy in children with medulloblastoma.

Thirteen children with medulloblastoma, were studied after 2 to 62 months off radiotherapy and chemotherapy with methotrexate and BCNU. Ages at time of study ranged from 2.3 to 15.7 years. Eleven patients, followed for a mean of 22 months, showed a significant decrease of height score, whereas nine patients had deficient growth hormone (GH) response to provocative tests. Clinical pubertal progression was normal in all patients, and three of five girls with advanced pubertal development had menarche. No evidences of gonadotropin disturbances were found in five patients whereas seven had raised basal follicle-stimulating hormone (FSH) level or FSH response to luteinizing hormone-releasing hormone (LH-RH). Abnormalities in thyrotrophin (TSH) secretion were found in 9 of 13 patients. This study shows that poor growth and GH deficiency were frequent in our patients. The high frequency of thyroid disturbances observed point out the need of evaluating thyroid function for adequate replacement therapy. Perhaps modification of adjuvant chemotherapy in the future can diminish drug-induced gonadal damage.

Adolescent↗
PubMed1987

Evaluation of gonadal function following long-term treatment for acute lymphoblastic leukemia in girls.

Twenty-four girls were studied following long-term treatment (mean: 50 months) for acute lymphoblastic leukemia; 14 were prepubertal and 10 pubertal. Follow-up during endocrine studies ranged from 2 months to 6.7 years (mean: 2.3 years). Five of 14 prepubertal patients started clinical pubertal development at a normal age and were reevaluated during puberty, increasing the pubertal group to 15 patients. Thirteen of 15 pubertal patients had received cranial radiotherapy. Ten of 15 pubertal patients started menses during the endocrine study. Although age of menarche was normal, in nine patients it was below the normal mean. Except for the remaining patient, all had received cranial cobalt therapy. In 6 of 19 patients bone age was significantly accelerated. Serum gonadotrophin response to LH-RH was normal in 13 prepubertal patients and in 10 pubertal patients. In 3 of 10 pubertal patients follicle-stimulating hormone (FSH) values were temporarily elevated. Only one pubertal patient had oligoamenorrhea. Five patients were studied by measuring serum progesterone on days 19-22 of the cycle to determine corpus luteum function. Three of them showed progesterone levels compatible with adequate corpus luteum function (6, 19, and 12 ng/ml, respectively) and two presented low progesterone levels (2 ng/ml), probably because of their short gynecological age (0.24 and 0.3 years, respectively). This study suggests that neither the disease nor the long-term antileukemia therapy seems to injure gonadal function in girls. A tendency to early sexual development was observed, which may be related to cranial cobalt therapy.

Acute Disease↗
PubMed1983

Testicular testosterone and dihydrotestosterone during sexual development in humans.

The concentrations of testosterone and dihydrotestosterone was determined in the human testis at different stages of sexual development, in patients with undescended testis or in subjects who had been treated for acute lymphoblastic leukemia. Patients were divided in three groups, prepubertal (Tanner's stage I), early puberty (Tanner's stages 2 + 3) and late puberty (Tanner's stages 4 + 5). Even though tubular diameter and serum testosterone followed the expected gradual rise during sexual maturation, testicular testosterone increased abruptly at early puberty, resulting in a high testicular: serum testosterone ratio at this stage. The testicular dihydrotestosterone:testosterone ratio was also high at early puberty. These data suggest that, at initiation of sexual development, seminiferous tubules receive a high androgen load, at a time when other androgen target organs are barely stimulated.

Adolescent↗
PubMed1983

Evaluation of testicular function following long-term treatment for acute lymphoblastic leukemia.

A study of reproductive function was carried out in 31 patients following long-term treatment of acute lymphoblastic leukemia (mean: 4 1/12 years); 17 prepubertal; nine pubertal, and five adults. Spontaneous clinical pubertal development was observed in 4 of 17 prepubertal patients. Serum testosterone response to hCG was normal or increased in the nine prepubertal patients studied. Intratesticular testosterone concentration was normal in 11 out of 12 patients. Only two of 14 prepubertal patients had a reduced number of germ cells. Normal progress of spermatogenesis was seen in six out of seven pubertal patients and only moderate hypospermatogenesis with focal hyalinosis was found in the five adults. Two of them had normal sperm count and one fathered two children. In six out of 14 prepubertal patients unexpected early signs of pubertal stimulation were found. Serum gonadotrophins response to LH-RH was normal in most patients. Testicular infiltration of blastic cells was found in four of 26 biopsies, but only one of 23 patients was without clinical signs of testicular relapse. Computerized axial tomography was normal in 10 out of 13 patients. Bone age was significantly below chronological age in four out of 15 patients. This study suggests that the gonad is moderately injured by long-term antileukemic therapy. In addition, microscopic testicular infiltration is not frequent in subjects without testicular enlargement.

Adolescent↗
PubMed1981

Testicular testosterone levels during puberty in cryptorchidism.

Serum and testicular concentrations of testosterone were determined by radioimmunoassay in four prepubertal patients (Tanner's genital stage G1) with unilateral cryptorchidism and in ten pubertal patients with different degrees of genital development (stages G2-G5), five with unilateral and five with bilateral cryptorchidism. In every case, testicular testosterone concentration was determined in the cryptorchid gonad. Two prepubertal autopsy cases were also studied. Results were compared with scrotal testes of adult subjects. Pubertal development resulted in a gradual increase in tubule diameter on microscopic examination notwithstanding the abnormal position of the gonad. As expected, serum testosterone also increased gradually throughout sexual development. Testicular testosterone concentration however increased to adult levels at early stages of puberty. Mean concentrations and ranges were: G1, 26 ng/g (range 7-49, n = 6); G2 + G3, 660 (range 37-1357, n = 6); G4 + G5, 438 (range 272-702, n = 4) and adults 520 (range 356-663, n = 4). This resulted in similar testicular: serum testosterone ratios in G1, G4 + G5 and adults but a high ratio in G2 + G3. Patients of groups G2 + G3 did not have elevation of serum gonadotrophins and did not show Leydig cell hyperplasia. Therefore, in early puberty, when peripheral tissues are exposed to low testosterone levels, seminiferous tubules of cryptorchid gonads might already receive high androgen stimulation.

Child↗
PubMed1980

Testicular function in varicocele.

Testicular testosterone concentration serum testosterone, LH and FSH, sperm count and testicular histology were evaluated in 17 patients with varicocele. Testicular testosterone was either normal or high (mean 906 +/- 723 ng/g of tissue), and serum testosterone was within the normal range in most patients. Serum LH was elevated in half of the patients. The degree of testicular damage observed was extremely variable and correlated with sperm analysis. Testicular testosterone tended to be higher in patients with severe microscopic lesions of the testis. It is concluded that even though Leydig cell function is partially altered, this deficiency is compensated by LH stimulation and therefore, failure of spermatogenesis is not secondary to low testosterone levels.

Adult↗
PubMedDate not supplied

Response to acute hCG stimulation and steroidogenic potential of Leydig cell fibroblastic precursors in humans.

The process of early testosterone (T) secretion and Leydig cell differentiation in humans was studied to explore the steroidogenic capacity of Leydig cell fibroblastic precursors. Seven cryptorchid boys received hCG prior to orchidopexy. Patients CP, PB, and MR received one injection of 1000 IU; patients JR and GG, three daily injections of 1000 IU, and patients MP and MM, five daily injections of 1000 IU. A testicular biopsy was obtained at the time of operation, 24 hours after the last injection. Serum T (ng/dl) before and after hCG stimulation and testicular T (ng/g) were determined by RIA. A control prepubertal testis (tumoral orchidectomy) was incubated in vitro and showed a time-dependent accumulation of T both in the medium and the testicular tissue. Testosterone released into the medium at 1, 2, and 4 hours was 0.76, 1.43, and 4.03 ng/ml, respectively. Tissue T at 0, 1, 2, and 4 hours was 9, 11, 16, and 24 ng/g, respectively. This indicates synthesis and secretion of T into the medium. Control testes showed abundant fibroblastic precursors with scanty cytoplasm, few organelles, heterochromatic nuclei, and minute nucleoli. No Leydig cells were present. After 1 day of hCG stimulation, numerous fibroblasts were activated, displaying enlarged cytoplasms with increased numbers of organelles, nuclei rich in euchromatin, and bigger nucleoli. No Leydig cells were present. Basal serum testosterone was 58.2 +/- 45.3 ng/dl and 87.3 +/- 42.0 after hCG administration, while testicular T was 974.0 +/- 686.0 ng/g (control prepubertal testicular T is 10-50 ng/g). After 3 days of hCG, activated fibroblasts increased and immature Leydig cells appeared. Basal serum T was 35.5 +/- 7.8 ng/dl and 394.0 +/- 24.0 after hCG stimulation, while testicular T rose to 2797.5 +/- 1222.6 ng/g. After 5 days, mature Leydig cells appeared for the first time. Serum T was 58 +/- 59.3 ng/dl (basal) and 641.5 +/- 390 ng/dl (after hCG); testicular T was 789 ng/g (patient MM did not have a value for testicular T). HCG induced numerous coated pits and endocytic vesicles in activated fibroblasts and young Leydig cells, suggesting receptor aggregation and internalization of hormone-receptor complexes. Peroxidase-antiperoxidase (PAP) localization of T was positive in peritubular fibroblasts and Leydig cells.(ABSTRACT TRUNCATED AT 400 WORDS)

Androgens↗
PubMedDate not supplied

Testicular and serum testosterone variations in squirrel monkeys during seasonal cyclicity.

The seasonal testicular maturation of squirrel monkeys (Saimiri sciureus) was used as a model of maturational hormonal regulation of the testis. Testicular testosterone and serum testosterone concentrations were determined during the circannual variations of body weight and testicular volume. These data have been correlated with changes in the germinal epithelium. According to individual weight curves and time of the year, the monkeys were divided into five groups: group A1, maximal weight, April-May; A2, July; A3, November; A4, minimal weight, February-March; and A5, March-April. Variations in testicular volume followed very closely variations in body weight. Sexual activity started at A1 and persisted in A2. A marked drop in the mean width of the germinal epithelium and the diameters of the seminiferous tubules was observed in A3, followed by a recovery during A4 and A5. Testicular testosterone showed two annual elevations. The first peak, 3.91 +/- 0.31 micrograms/g (mean +/- SE), coincided with the serum testosterone peak when body weight and testicular volume were high and the trophic response of the germinal epithelium was complete. The second peak reached levels of 5.21 +/- 1.48 micrograms/g and was observed before the reinitiation of spermatogenesis. This was accompanied by a moderate increase in serum testosterone. The second peak of testicular testosterone, which has been reported to occur in the rat and in humans, might represent a local androgen need for initiation of spermatogenesis, while the first peak might represent the androgen need for full stimulation of spermatogenesis.

Animals↗
PubMedDate not supplied

Thyroid function and serum IGF-1 in children before and after liver transplantation.

We report results of serum thyroid hormone and IGF-1 concentrations in 20 children, 1.2 to 13.6 years old, with various degrees of chronic liver dysfunction (CLD), before and after successful orthotopic liver transplantation (OLT). Ten children presented with moderate chronic liver disease (CLD-M) with prothrombin time (PT) > 50% and serum albumin concentration > 3 g/dl; 7 children had severe chronic liver disease (CLD-S) with PT < 50% and serum albumin concentration < 3 g/dl; and 7 children who had received an OLT, who had normal liver function at the time of the study. Four of the latter group were also studied before OLT. Patients with CLD-M had normal mean +/- SD serum levels of total T3 (2.0 +/- 0.7 nmol/l), total T4 (125 +/- 25.9 nmol/l) and fT4 concentrations (16 +/- 2.8 pmol/l). In contrast, children with CLD-S showed a significant decrease in thyroid hormones together with normal basal TSH values (T3 0.8 +/- 0.0 nmol/l; T4 45.6 +/- 19.5 nmol/l; fT4 7.4 +/- 1.1 pmol/l; TSH 3.8 +/- 0.9 mU/l). Patients who received a successful OLT showed mean peripheral thyroid hormone concentrations significantly higher than CLD-S patients (T3 1.7 +/- 0.7 nmol/l, p < 0.005; T4 92.8 +/- 18.2 nmol/l, p < 0.001; fT4 14.5 +/- 3.1 pmol/l, p < 0.001). A significant correlation was found between thyroid hormone levels and PT or serum albumin. In the nine patients with CLD-M and CLD-S in whom serum IGF-1 concentration was measured, values found (mean +/- SD 0.08 +/- 0.05 U/ml) were below the 95% confidence limit of matched controls.

Adolescent↗
PubMedDate not supplied

Growth hormone--insulin-like growth factor-I (IGF-I) axis in prepubertal children with chronic renal failure.

UNLABELLED: The hypothalamic-pituitary insulin-like growth factor I (IGF-I) axis was evaluated in 12 children with chronic renal failure (CRF) aged 3.2 to 16.5 yr (mean 9.5) on chronic dialysis, and in 13 renal transplantation patients aged 7.5 to 15.0 yr (mean 11.1). Height standard deviation score (SDS) was -2.8 +/- 0.5 (mean +/- SE) and -3.0 +/- 0.3 SDS (p = NS), and growth velocity was 3.7 +/- 0.4 and 1.5 +/- 0.3 cm/year (p < 0.01), respectively. Mean nocturnal growth hormone (mean GH) and number of pulses > 5 ng/ml in CRF and transplantation children were 4.2 +/- 0.8 vs 2.4 +/- 0.3 ng/ml, p = 0.08 and 1.7 +/- 0.2 vs 1.0 +/- 0.2, p < 0.05, respectively. In transplant children there was a positive correlation between mean GH and growth velocity (p < 0.02). GH peak response and the area under the curve post GH releasing hormone test were significantly higher in CRF and transplant children treated with deflazacort (new steroid derived from prednisolone) vs transplant children treated with methylprednisone. Mean serum IGF-I levels were -0.5 +/- 0.2 SDS for chronological age (CA) in CRF patients and +0.8 +/- 0.2 SDS(CA) in transplant patients, p = NS. In the latter, serum IGF-I values were positively correlated with growth velocity (p < 0.02) and negatively correlated with methylprednisone dose (p < 0.05). CONCLUSIONS: Patients with CRF and growth retardation have a higher number of GH peaks and slightly elevated mean GH levels compared to transplant patients. After renal transplantation GH secretion may be influenced by glucocorticoids as shown by the lower GH response to GHRH which improved with deflazacort and the inverse correlation between methylprednisone dose and IGF-I levels.

Adolescent↗