Showing papers by "University of Cagliari published in 1980"

Cryptic 21-hydroxylase deficiency in families of patients with classical congenital adrenal hyperplasia.

Abstract: Serum androgens and 17-hydroxyprogesterone concentrations and HLA genotypes were determined in 124 families of patients with congenital adrenal hyperplasia due to 21-hydroxylase deficiency (CAH). In 8 pedigrees, we discovered 16 pubertal or postpubertal family members of either sex who had biochemical evidence of 21-hydroxylase deficiency but were without clinical symptoms of excess virilism, amenorrhea, or infertility. We designated these family members as individuals with cryptic 21-hydroxylase deficiency. Within each generation, the family members with cryptic 21-hydroxylase deficiency were HLA identical. It is proposed that these family members are genetic compounds, having 21-hydroxylase deficiency as a result of two recessive gene defects: 1) a severe 21-hydroxylase gene defect present in the index case with classical CAH (21-OHCAH) and 2) a mild 21-hydroxylase gene defect (21-OHCRYPTIC). Thus, the CAH genotype in the family members with cryptic 21-hydroxylase deficiency is 21-OHCAH/21-OHCRYPTIC. Lod score analysis for linkage between the cryptogenic 21-OH trait and HLA gave a combined Lod score for males and females of theta = 0.00 of 3.409. Close genetic linkage between HLA and 21-OHCRYPTIC was thus established. This study provides support for the previously reported heterogeneity of 21-hydroxylase deficiency which may result from allelic variability at the locus for steroid 21-hydroxylase.

Antiviral activity of glycyrrhizic acid.

Abstract: Glycyrrhizic acid inhibits the growth of several DNA and RNA viruses in cell cultures and inactivates Herpes simplex 1 virus irreversibly.

Neuroendocrine effects of quipazine in man in health state or with neurological disorders

Abstract: The endocrinological actions of quipazine, a direct serotonin receptor agonist, were investigated in both normal subjects (NS) and individuals with neurological disorders,i.e., Huntington's disease (HD), myoclonic epilepsy (ME) and cluster headache (CH). In both normal subjects and neurologic patients inconsistent and variable changes in the secretion of anterior pituitary hormones were observed. In fact, oral administration of 50 mg of quipazine elicited a rise in plasma GH in only 9/23 subjects investigated (3 NS, 2 HD, 1 ME, 3 CH), decreased GH in 4 subjects (1 NS, 2 HD, 1 CH) and left unmodified plasma GH in the remaining 10 subjects. Only 7/23 subjects showed a positive PRL response to quipazine (2 NS, 1 HD, 1 ME, 3 CH), in one subject (CH) PRL was inhibited while the drug was ineffective in the remaining 15 subjects. For gonadotropins, 5/21 subjects (2 NS, 1 HD, 2 CH) had a positive LH response and 3/20 subjects (1 NS, 1 ME, 1 CH) had a positive FSH response. In one subject (HD) there was inhibition of baseline LH levels and no effects were present in the remaining individuals. No changes in basal TSH levels were present in the 6 subjects investigated (4 NS, 2 ME). Quipazine was instead competent to increase plasma cortisol levels in 6/8 normal subjects. Pharmacodynamic, mainly gastrointestinal, effects of the drug were present in about 50% of the subjects but were not or only poorly correlated with the endocrine responses. Collectively, based on the neuropharmacologic profile of the drug, and in contrast to many animal data, these findings do not support a major role for the serotoninergic system on basal anterior pituitary hormone secretion in man, possibly with the exception of the ACTH-cortisol secretion.

Growth hormone-releasing effect of an enkephalin analog in the dog: evidence for cholinergic mediation.

Abstract: The GH-releasing effect of a potent enkephalin analog, [D-Ala2, MePhe4, Met(o)5-ol]enkephalin (DAMME) and its possible mechanism(s) of action were investigated in unanesthetized dogs. DAMME injected iv into 14 male and female beagles (34 tests) at doses of 2.0, 4.0, 8.0, and 16.0 μg/kg induced clear-cut and dose-related rises in canine GH (cGH) levels. Peak cGH levels occurred 15–30 min post injection and cGH levels were still elevated at 120–180 min. Prior administration of the opiate antagonist naloxone (0.5 mg/kg iv) completely suppressed the hormonal response to DAMME (8 μg/kg) without significantly altering baseline cGH levels. Blockade of serotonin receptors by metergoline (1 mg/kg, orally 60 min before) induced a slight increase in cGH levels but did not modify the GH-releasing effect of DAMME. Subchronic administration of pimozide (1 mg, orally three times daily for 2 days and 3.0 mg orally 120 min before), a blocker of dopamine receptors, significantly reduced the peak cGH rise induced by DAMME. Complete suppression of the GH-releasing effect of DAMME was induced by blockade of cholinergic muscarinic receptors by atropine (80 μg/kg, sc 30 min before) but not by butyl-scopolamine (0.5 mg/dog, iv 30 min before), an anticholinergic drug which does not cross the bloodbrain barrier. Pretreatment with eserine (0.5 mg/dog, iv 15 min before), a reversible inhibitor of cholinesterase, was unable to potentiate the GH-releasing effect of a threshold dose of DAMME but induced a rise in plasma cGH levels per se. These results indicate that enkephalins are potent GH releasers in the dog and that cholinergic mediation plays an essential role in this effect. © 1980 by The Endocrine Society.

Suppression of REM and delta sleep by apomorphine in man: a dopamine mimetic effect.

Abstract: Apomorphine, a direct stimulant of dopamine receptors, was given in nonemetic doses by continuous IV infusion for 180–240 min during night sleep in normal subjects. During apomorphine infusion, a significant reduction of stage (S)4 and an abolition of rapid eye movement (REM) sleep occurred. The percent duration of S2 was significantly increased. In the 240 min following interruption of a 240-min infusion of apomorphine, a significant increase of S4 and REM percent duration was observed. The effect of apomorphine infusion on sleep was prevented by the administration of haloperidol or sulpiride, two dopamine receptor blocking agents. This suggests that it is due to a dopamine minetic action.

Trisomy 16q21 = to qter.

Abstract: A case of trisomy 16q secondary to a paternal 16/18 translocation is described. A comparison of this case with the few other cases of trisomy 16q described in the literature indicates that trisomy for the long arm of chromosome 16 results in a severely affected phenotype and early death. Conversely, patient with trisomy 16p do not have gross abnormalities. We postulate that the prenatal lethality of full trisomy 16 is mainly due to the trisomy for the long arm.

Secretory mechanisms of human ceruminous glands: a transmission and scanning electron microscopic study.

Abstract: Two secretory mechanisms (eccrine and apocrine) were observed by transmission and scanning electron microscopy in the same secretory cells of the human ceruminous glands. The eccrine secretion occurs as a typical exocytosis by fusion of the limiting membrane of the secretory granule with the apical plasmalemma. The apocrine secretion is more complex and takes place by sequential steps: bulging of the cellular apex into the lumen, constriction of the projection, and detachment of it from the cell. This mechanism generally causes the removal of the entire projection all at once by decapitation at its base; some variations of this process have been found, however, and are described in the present work. A double membrane, apparently separating the apical protrusion from the rest of the cell, is noticeable in our photographs. Nevertheless, even if this membrane is very similar to a demarcation layer, we consider it as an intercellular double membrane separating two obliquely sectioned cells.

Electron spin resonance and electronic spectral investigation on square planar copper(II) complexes ofN-ethyl- andN-propylimidazole

Abstract: Electron spin resonance studies have been carried out onN-ethylimidazole andN-propylimidazole 4 : 1 complexes of CuX2 salts (X = ClO 4 − , NO 3 − , , Br− or Cl−) in their polycrystalline and undiluted form at 295 K and 77 K. Cupric ion hyperfine structural resolution is observed for all the complexes at 295 K and the spectra are characteristic of a CuN4 chromophore with axial symmetry. In complexes involving ClO , Br− and Cl− the anions are nonbonding, whereas those with the NO 3 − anion are weakly bonding. The electronic and e.s.r. spectral data have been correlated. The resolution of Cu2+ ion hyperfine structure in these complexes is attributed to a decrease in the dipolar interaction and has been observed for the first time since the first resolution reported in 1954 for CuN4 coordination with square planar symmetry for α,β,ν,σ-tetraphenylporphyrincopper (CuTPP).

Ethanol effects on dopaminergic function: Modulation by the endogenous opioid system

Abstract: Different behavioral and biochemical data suggest that ethanol has different effects on central dopaminergic transmission in rat and mouse. We found that ethanol induces an increase of striatal dopamine turnover which does not persist after chronic drinking. Following chronic ethanol treatment, we observed the development of supersensitivity of the striatal dopamine (DA) recognition sites, in terms of an enhanced affinity. We investigated various experimental models to clarify the existence of an enkephalinergic modulation of ethanol effects on the dopaminergic system. We found that in the rat, a pretreatment with naloxone abolishes the striatal DA turnover increase observed after ethanol. DBA 2J mice, which differ from C57 BL/6J and Swiss Albino, by genetically lacking enkephalinergic modulation on dopaminergic activity in the striatum, do not show any change of DA metabolism after acute ethanol. In the rat retina, where we hypothesized a less operant regulation of dopaminergic activity by enkephalins, tolerance does not develop after chronic drinking to the increase in DA turnover as it did in striatum. Our results confirm the importance of the endogenous opioid system in the regulation of the ethanol induced neurochemical and behavioral effects.

Prenatal Diagnosis of β Thalassaemia by Fetal Red Cell Enrichment with NH4Cl‐NH4HCO3 Differential Lysis of Maternal Cells

Abstract: Prenatal diagnosis with globin chain synthesis analysis on fetal red blood cells concentrated by NH4Cl-NH4HCO3 differential lysis of maternal cells (Orskov lysis) was carried out in 27 pregnancies at risk for beta thalassaemia and one at risk for sickle cell beta0 thalassaemia. The beta/gamma globin chain synthesis ratio was also determined after anti-i-differential agglutination (12 cases), in almost pure fetal samples (sic cases) and by extrapolation (one case). Differential lysis permitted the study of samples drawn by placental aspiration containing as little as 3.2% fetal red blood cells. There was no consistent difference between the beta/gamma ratios observed after differentail lysis and those determined after the use of the other approaches. A presumptive diagnosis of homozygous beta thalassaemia was made in nine cases. All but one of these pregnancies was terminated. The absence of beta chain synthesis was confirmed by the study of fetal blood after abortion in four cases with suitable samples. Of the remaining pregnancies, six proceeded to term and non-homozygous infants were delivered. The others are still in progress. No fetal loss occurred. Orskov lysis seems to be a very reliable method for prenatal diagnosis of beta chain abnormalities. Moreover it can minimize the number and duration of placental aspirations required and thus the risk to the fetus.

Interaction between the Glucose‐6‐Phosphate Dehydrogenase Deficiency and Thalassaemia Genes at Phenotype Level

Abstract: No significant differences were observed in the mean values of Hb A2 levels and red cell indices between G6PD- and G6PD+ beta thalassaemia carriers apart from the MCV, which was significantly higher in beta thalassaemia G6PD- subjects, but still in the thalassaemia carrier range. No difference was seen between G6PD+ and G6PD- alpha thalassaemia carriers. G6PD+ beta thalassaemia carriers show a significant increase in G6PD levels expressed as activity per g of Hb and to lesser extent as activity per number of red cells x 10(9); in G6PD+ alpha thalassaemia carriers this increase is statistically significant only when the enzyme levels are expressed as activity per g of Hb. G6PD- beta thalassaemia carriers had enzyme levels higher than non-thalassaemic G6PD- subjects only when the activity is expressed per g of Hb. G6PD activity was found to be increased in G6PD+ and G6PD- Hb H disease patients.

Methodology in experimental infections of mice with Hymenolepis nana

Abstract: A “natural” infection technique based on the uptake of eggs with feed is described. The ratio of the number of parasites recovered 14 days post infection to the number of eggs given (q ratio) is close to 1 if few eggs are given (⋍ 5 per mouse). In the same conditions, q is less in mice infected with ⋍ 50 or ⋍ 500 eggs. The larger the number of parasites, the faster their spontaneous elimination. Total elimination or “self-cure” may be attained even in the case of large numbers. In mice infected with many eggs, following treatment with ionizing radiations, q is greater than in the controls. Two subsequent infections mutually interfere with each other. The challenge is partly damaged if it is given 24 hours after the first infection and is completely inhibited if it takes place 4 or more days later. The first infection may be partly damaged by the challenge. Problems concerned with infection technique, parasite distribution in single mice, parasite/host equilibrium and with host immune response are...