PubMed Health⌕ Search

Biomedical subjects

C Ferretti

Publications and source records attributed to C Ferretti.

At least 55 records · Page 3Linked to original sources
PubMed1991

Sexual dimorphism in [3H]histamine binding sites of rat cerebral cortex.

[3H]Histamine binding sites, identified on rat brain homogenate membranes, displayed sexual dimorphism with higher density and lower affinity in preparations from adult female compared to the males. The ontogenetic development of [3H]histamine binding sites was studied in male and female brain cortex neural membranes. Histamine binding sites were detectable in newborn-10 day old rats. Density increased with age, reaching adult levels at 37-45 days. No significant differences between sexes were observed in the binding constants until 37 days after birth, when the [3H]histamine binding characteristics began to differentiate according to sex. Sexual dimorphism in brain histamine binding site development appeared to depend on ovarian steroids. Binding patterns in immature female rats which were ovariectomized at 21 days and killed at 37+ were similar to those found in males. On the other hand, when oestradiol replacement was administered for 10 days to ovariectomized rats a total recovery of [3H]histamine binding pattern was obtained, which was comparable to that observed in intact female rats of the same age.

Aging↗
PubMed1991

Effects of long-term treatment with naltrexone on hepatic enzyme activity.

The influence of naltrexone on liver function in heroin addicts was studied, with respect to the metabolizing function by using the antipyrine clearance and to cellular damage by monitoring plasma levels of hepatic enzymes. The clearance of antipyrine was not affected by naltrexone treatment, and, during the study period, the use and withdrawal of benzodiazepines and alcohol did not change this parameter; moreover, there was no relationship between changes in plasma hepatic enzymes and antipyrine half-life. Mean plasma levels of hepatic enzymes did not show significant modification in the course of treatment with naltrexone.

Administration, Oral↗
PubMed1991

Dapiprazole compared with clonidine and a placebo in detoxification of opiate addicts.

The activity of dapiprazole, clonidine and a placebo were studied to reduce abstinence symptoms and modify the psychological outline during a withdrawal period in heroin addicts. Forty heroin addicts were treated in a double-blind design and, within two weeks, relapse in heroin use was higher in the placebo group (8/10) in comparison with the dapiprazole (1/20) and clonidine (0/10) groups. During treatment clonidine was able to reduce depression and paranoid-ideas scores, whereas dapiprazole reduced depression, anxiety, hostility, phobic anxiety, obsessiveness and psychoticism. Side-effects were mild and it may be concluded that both dapiprazole and clonidine are effective and safe drugs for the treatment of opiate withdrawal syndrome.

Adolescent↗
PubMed1991

[Hematocrit and hemoglobin, parameters of hematic viscosity, in pregnancy-induced hypertension].

During pregnancy because of physiologic hemodiluition and changes in various plasma protein levels, plasma viscosity is decreased compared to the non pregnant condition. Specifically the whole blood viscosity profile throughout pregnancy follows that of the hematocrit. However some pathological condition like pregnancy induced hypertension and intrauterine growth retardation are characterized by an increase of plasma viscosity. In order to evaluate the effect of plasma viscosity on placental perfusion, in 41 patients affected by pregnancy induced hypertension and with no iron deficiency we compared maternal hemoglobin and hematocrit to the birth weight. High maternal hemoglobin and hematocrit levels were associated to an increased frequency of low weight for date newborns (less than or equal to 10th centile), although the relationship with the hemoglobin levels is stronger (p less than or equal to 0.02) than the one with the hematocrit (p less than or equal to 0.05). In contrast, high weight for date newborns (greater than or equal to 90th centile) were not related to maternal hemoglobin and hematocrit parameters. We found that maternal hemoglobin and hematocrit, indicators of plasma viscosity, are useful in predicting low birth weight, but not high birth weight. We speculate that hypoxia due to the modification of microcirculation is a very important factor in determining the low birth weight; in contrast the oxygen is not the only factor involved in determining the high birth weight.

Blood Viscosity↗
PubMed1990

Differential effects of indolepyruvic acid and 5-hydroxytryptophan on indole metabolism in the pineal gland of the rat during the light-dark cycle.

The effect of two serotonin precursors, 5-hydroxytryptophan (5-OH-TRP) and indolepyruvic acid (IPA), a tryptophan ketoanalogue, on rat pineal indole metabolism during the light-dark cycle was investigated. 5-OH-TRP drastically increased the production of 5-hydroxyindoleacetic acid at a dose of only 10 mg/kg, whereas 50-100 mg/kg was needed to reach higher serotonin levels. It had no effect on the pathway leading to the production of N-acetylserotonin and melatonin. IPA, on the other hand, led to a marked dose-related increase in tryptophan, 5-OH-TRP, serotonin and 5-OH-indoleacetic acid, and was also active on N-acetylserotonin and melatonin synthesis in both phases. The different behaviour of these two substances with regard to melatonin synthesis was also confirmed by their effects on N-acetyltransferase, since IPA increased, whereas 5-OH-TRP decreased its activity. These data suggest that an increase in serotonin does not necessarily lead to an increase in melatonin, and that IPA may in fact induce this effect by altering the activity on N-acetyltransferase, which is regarded as a key enzyme in pineal hormone synthesis.

5-Hydroxytryptophan↗
PubMed1990

Walker-Warburg syndrome. Case report and literature review.

The Walker-Warburg syndrome (WWS) is a fatal dysmorphic disorder of unknown etiology, but strongly suggests an autosomal recessive mode of inheritance. It is characterized by severe congenital oculo-cerebral malformations (lissencephaly, congenital hydrocephalus, and ocular lesions). The authors report a case of WWS that occurred in a consanguineous union, with a review of the literature. Possible pathogenesis, and disorders sharing the features of WWS are discussed. Families-at-risk for WWS should be identified for prenatal diagnosis and for genetic counselling.

Abnormalities, Multiple↗
PubMed1990

Effects of acute hypoxia on the normal and diseased sinus node.

We have studied the effects of breathing 12% oxygen in three groups of patients with sinus bradycardia: 11 with intrinsic sick sinus syndrome, 11 with extrinsic sick sinus syndrome and 11 without any evidence of sinus dysfunction. During hypoxia, the heart rate increased by an average of 6.7 beats/min in the patients with intrinsic sick sinus syndrome, 15.7 beats/min in the patients with extrinsic sick sinus syndrome and 14.3 beats/min in those with normal sinus node function. The difference in response of the heart rate between the two groups with sick sinus syndrome was highly significant (P less than 0.001). There was no difference between the three groups in the response of the blood pressure, ventilation, and partial pressures of oxygen and carbon dioxide. The increased heart rate which accompanies hypoxia is thought to be mediated through sympathetic mechanisms consequent on hyperventilation. In the intrinsic sick sinus syndrome, there is evidence that the sympathetic tone is already increased and this may limit the extent of the tachycardia due to hypoxia. Hypoxia may be a useful clinical test to distinguish between the two forms of sick sinus syndrome.

Blood Pressure↗
PubMed1990

[Ventricular tachycardia induced by a bent catheter electrode migrated to the pulmonary artery].

The possibility of migration of a transvenous electrode bend in the infundibulum of the pulmonary artery is a very rare complication of permanent pacing. The Authors describe the case of a patient whose transvenous electrode, positioned in the pulmonary artery 5 years after implantation, was presumably the cause of a ventricular hyperkinetic arrhythmia (VT) and of cerebral disturbances (sublipothymia, syncope). The re-position of the electrode removed the arrhythmia thus considerably improving the symptoms of the patient.

Aged↗
PubMed1989

Are the catecholestrogens involved in estrogen-induced striatal dopamine receptor supersensitivity?

The ability of tamoxifen, an antiestrogen agent, to antagonise the striatal dopamine receptor hyperactivity induced in rats by chronic treatment with 17 beta-estradiol and 2-hydroxyestradiol or with two receptor blockers (haloperidol and sulpiride) was compared. It was found that tamoxifen antagonised both the increase in [3H]spiperone binding sites and the stereotyped behaviour induced by apomorphine in animals treated with the two steroids but had no effect in animals receiving the two dopamine blockers. These results run counter to the view that introduction of a catechol group in a steroid molecule is of decisive importance in the induction of striatal dopamine receptor hypersensitivity.

Animals↗
PubMed1989

Kabuki makeup syndrome (Niikawa-Kuroki syndrome) in a black child.

Kabuki makeup syndrome (KMS), also known as Niikawa-Kuroki syndrome, is a dysmorphic disorder of unknown etiology, characterized by unusual facies, large protruding ears, postnatal dwarfism, and mental retardation. The syndrome has been seen almost exclusively in Japanese children. We report a case of KMS that occurred in a child of mixed ethnicity. Differential diagnosis is discussed.

Child, Preschool↗
PubMed1988

Tamoxifen counteracts estradiol induced effects on striatal and hypophyseal dopamine receptors.

UNLABELLED: We investigated the ability of Tamoxifen (TAM), an antiestrogen drug, to counteract the modifications induced by estrogens on dopamine (DA) receptors on striatum and on adenohypophysis of ovex female rats. Subacute treatment with 17 beta-estradiol (E2) at both low (0.1 micrograms/kg) and high (20 micrograms/kg) doses confirmed its ability to increase the number of striatal 3H-Spiperone (3H-SPI) binding sites in a dose dependent manner. By contrast in the pituitary, only high doses of estrogen were effective in reducing the number of DA receptors. We treated ovex female rats for 15 days with TAM alone or associated with E2, to see if these estrogenic effects could be suppressed by an antiestrogenic drug. TAM did not affect the number of striatal DA receptors, but significantly increased the adenohypophyseal DA binding sites, without varying their affinity. No changes were observed in pituitary and striatal DA receptor density, even when TAM was injected in association with estradiol. IN CONCLUSION: TAM is able to counteract the effects estrogens have on DA receptors. However there is some evidence that it could influence the pituitary DA systems independently of its antiestrogenic activity.

Animals↗
PubMed1987

Ophthalmologic findings in the fragile X syndrome.

The fragile X (Fra[X]) syndrome is a commonly encountered X-linked recessive chromosomal disorder associated with mental retardation that primarily affects males. The demonstration of a fragile site in the long arm of the X chromosome (Xq27-28) through special culture techniques confirms the diagnosis. Phenotypic features are often lacking, especially in early life. We studied the ophthalmologic and clinical characteristics of 15 patients (13 male and two female) with the Fra(X) syndrome and reviewed the clinical picture of the disorder. Strabismus was the most prevalent ophthalmologic abnormality and was observed in six patients. The frequent occurrence of strabismus in our series suggests that it is a commonly associated abnormality. It is recommended that the Fra(X) syndrome be added to the list of genetic and dysmorphic disorders with which strabismus is frequently associated.

Adolescent↗
PubMed1986

The effects of a long term dihydroergotoxine treatment on agonist and antagonist striatal dopamine binding sites are dose and age related.

Chronic administration of dihydroergotoxine, at the two doses of 2.5 mg/kg and 5 mg/kg decreases the binding of dopamine 3H-agonists to striatal membranes. By contrast the binding of dopamine 3H-antagonists is decreased in the animals treated with the higher dose and increased in those treated with the lower one. In old rats, in which a partial loss of both 3H-antagonist and 3H-agonist binding sites is observed, the DHT treatment confirms to increase the binding of 3H-antagonists, without affecting that of 3H-agonists. Thus, aging and ergot alkaloids seem to discrimate between DA-agonist and DA-antagonist receptor sites suggesting that this receptors are separate entityes.

Aging↗
PubMed1986

Effects of sustained hyperprolactinemia induced by chronic treatment with domperidone on central dopaminergic systems in the rat.

Chronic treatment with Domperidone (DOM) had no effect on basal prolactin (PRL) secretion or basal levels of Dopamine (DA) metabolites in basal hypothalamus and striatum as compared with the vehicle treated rats. Animals chronically treated with DOM did not present tolerance to a challenge dose of Haloperidol (HAL) and DOM either measuring PRL secretion or striatal DA metabolite levels. The PRL-induced increase in hypothalamic 3,4-dihydroxyphenylacetic acid (DOPAC) was reduced. These results were accompanied by no change at striatal DA receptors, a slight reduction in density-affinity at hypothalamic DA receptors but clear-cut modification in pituitary DA receptors with the appearance of a high affinity-low capacity binding sites. It can be surmised that sustained hyperprolactinemia may induce tolerance in hypothalamic Tuberoinfundibular (TIDA) neurons involved in the inhibitory control of PRL secretion and a change in the kinetic properties of pituitary DA receptors, but it does not consistently affect the activity of the nigro-striatal DA system.

3,4-Dihydroxyphenylacetic Acid↗