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N Aste

Publications and source records attributed to N Aste.

At least 55 records · Page 3Linked to original sources
PubMed1994

Morphometric studies demonstrate that aromatase-immunoreactive cells are the main target of androgens and estrogens in the quail medial preoptic nucleus.

The volume and cytoarchitectonic organization of the sexually dimorphic medial preoptic nucleus (POM) of the quail are sensitive to plasma levels of testosterone (T). We previously showed that, in castrated quail, T or its estrogenic metabolite, estradiol (E2), increases the size of the large neurons located in the lateral part of POM. Embryonic treatments with estrogens are also known to affect permanently the size of these large neurons. Since the lateral POM also contains a dense population of aromatase-immunoreactive (ARO-ir) cells, and these are known to be a target for steroids, we hypothesized that the effects of steroids identified in previous experiments were primarily directed to these ARO-ir cells. This idea was tested in two experiments in which the size of these cells was measured in male quail under various endocrine conditions. In experiment 1, a detailed analysis of ARO-ir and of non-immunoreactive cells in the POM of adult, sexually mature males revealed that the immunoreactive perikarya are larger than the non-immunoreactive cells and that they constitute the vast majority of the large cells (area > 50 microns 2) in the POM. In experiment 2, it was shown that T and E2 actually increase the size of ARO-ir cells in the POM while the androgenic metabolite of T, dihydrotestosterone has no effect at this level. Taken together, these data suggest that the sex differences and the steroid-induced changes in cell size previously described in the study of POM sections stained for Nissl material largely concern aromatase-containing cells. Since aromatization of T plays a limiting role in the activation of male copulatory behavior, these changes may represent the morphological signature of the mechanisms causally involved in the control of this behavior.

Androgens↗
PubMed1994

Afferent and efferent connections of the sexually dimorphic medial preoptic nucleus of the male quail revealed by in vitro transport of DiI.

The medial preoptic nucleus of the Japanese quail is a testosterone-sensitive structure that is involved in the control of male copulatory behavior. The full understanding of the role played by this nucleus in the control of reproduction requires the identification of its afferent and efferent connections. In order to identify neural circuits involved in the control of the medial preoptic nucleus, we used the lipophilic fluorescent tracer DiI implanted in aldheyde-fixed tissue. Different strategies of brain dissection and different implantation sites were used to establish and confirm afferent and efferent connections of the nucleus. Anterograde projections reached the tuberal hypothalamus, the area ventralis of Tsai, and the substantia grisea centralis. Dense networks of fluorescent fibers were also seen in several hypothalamic nuclei, such as the anterior medialis hypothalami, the paraventricularis magnocellularis, and the ventromedialis hypothalami. A major projection in the dorsal direction was also observed from the medial preoptic nucleus toward the nucleus septalis lateralis and medialis. Afferents to the nucleus were seen from all these regions. Implantation of DiI into the substantia grisea centralis also revealed massive bidirectional connections with a large number of more caudal mesencephalic and pontine structures. The substantia grisea centralis therefore appears to be an important center connecting anterior levels of the brain to brain-stem nuclei that may be involved in the control of male copulatory behavior.

Afferent Pathways↗
PubMed1993

Distribution and characterization of melatonin receptors in the brain of the Japanese quail, Coturnix japonica.

2-[125I]iodomelatonin was used to study the distribution and properties of the melatonin receptor in the Japanese quail brain. High receptor density was detected in the major targets of direct retinal input (optic tectum, nucleus of the optic basal rout, ventrolateral geniculate nucleus), as well as areas representing terminals in the visual pathways (nucleus rotundus, ectostriatum, thalamo-hyperstriatal pathway). Binding was also found in the piriform cortex, the hypophyseal pars tuberalis, the oculomotorius nucleus and the associated Edinger-Westphal nucleus, and in the nuclei of the third, fourth and sixth cranial nerves. A comparison of the receptor pharmacological profile to that of the mammalian brain demonstrated pharmacological identity of the two binding sites. In the saturation experiments, GPT gamma S decreased the binding affinity, numerical Kd values increasing from approximately 35 pM to approximately 150 pM.

Animals↗
PubMed1993

Implication of testosterone metabolism in the control of the sexually dimorphic nucleus of the quail preoptic area.

In quail, testosterone (T) activates male copulation and affects the volume and cytoarchitectonic organization of the medial preoptic nucleus (POM). T metabolism (especially its aromatization) is critical for the production of these behavioral effects. We wondered whether T metabolism is also playing a role in the induction of the morphological changes in POM. We compared the effects of T and of its metabolites in this nucleus. To obtain an independent evaluation of the role played by aromatase, morphological effects of T associated or not with the aromatase inhibitor R76713 were also assessed. As previously observed, T increased the POM volume and the cross-sectional area of the neurons in the lateral part of the nucleus. The effects of T on the neurons in the lateral POM were mimicked in part by the combined treatment with estradiol and 5 alpha-dihydrotestosterone. They were also blocked by the aromatase inhibitor. This suggests that T aromatization plays a critical role in the mediation of the cytoarchitectonic effects of T. A specific role for androgens alone remains to be established.

Animals↗
PubMed1991

The serotoninergic system in the brain of the Japanese quail. An immunohistochemical study.

The presence and topographical localization of the serotoninergic system in the brain of the Japanese quail (Coturnix coturnix japonica) have been studied by means of peroxidase-anti-peroxidase immunocytochemistry. The perimeter, diameter, area, and shape factor of immunoreactive cells have been recorded and analyzed morphometrically for intra- and interspecies comparison. The data reported here confirm and extend results previously obtained in the brain of other avian species. Serotonin-immunoreactive neurons of the quail are mainly located in the hypothalamic paraventricular organ and adjacent areas, and in the brainstem where they form three separate groups. The first of these groups consists of small-sized neurons located in the ventro-rostral mesencephalon. The second group is composed of medium-sized neurons located in the dorsal mesencephalo-pontine region. The third group is also formed by medium-sized neurons, and is located ventrally in the ponto-medullary region. In the quail brain, serotoninergic neurons are not restricted to nuclei located in the vicinity of the midsagittal plane, but show some lateralization, especially in the brainstem. The organization of the different groups of immunoreactive neurons based on this topographical distribution and morphometric analysis has been compared with descriptions of the serotoninergic system in other birds. Serotonin-immunoreactive nerve fibers are widely distributed throughout the brain, but appear to be particularly abundant in regions involved in the control of reproductive activities, such as the septal region, the medial preoptic nucleus, the nucleus intercollicularis, and the external zone of the median eminence. The data reported here have allowed the drawing of a map of serotonin-immunoreactive structures.

Animals↗
PubMed1991

Localization of neuropeptide Y-immunoreactive cells and fibres in the brain of the Japanese quail.

In the present study, we have demonstrated, by means of the biotin-avidin method, the widespread distribution of neuropeptide Y (NPY)-immunoreactive structures throughout the whole brain of the Japanese quail (Coturnix coturnix japonica). The prosencephalic region contained the highest concentration of both NPY-containing fibres and perikarya. Immunoreactive fibres were observed throughout, particularly within the paraolfactory lobe, the lateral septum, the nucleus taeniae, the preoptic area, the periventricular hypothalamic regions, the tuberal complex, and the ventrolateral thalamus. NPY-immunoreactive cells were represented by: a) small scattered perikarya in the telencephalic portion (i.e. archistriatal, neostriatal and hyperstriatal regions, hippocampus, piriform cortex); b) medium-sized cell bodies located around the nucleus rotundus, ventrolateral, and lateral anterior thalamic nuclei; c) small clustered cells within the periventricular and medial preoptic nuclei. The brainstem showed a less diffuse innervation, although a dense network of immunopositive fibres was observed within the optic tectum, the periaqueductal region, and the Edinger-Westphal, linearis caudalis and raphes nuclei. Two populations of large NPY-containing perikarya were detected: one located in the isthmic region, the other at the boundaries of the pons with the medulla. The wide distribution of NPY-immunoreactive structures within regions that have been demonstrated to play a role in the control of vegetative, endocrine and sensory activities suggests that, in birds, this neuropeptide is involved in the regulation of several aspects of cerebral functions.

Animals↗
PubMed1991

Immunocytochemical distribution of glial fibrillary acidic protein in the central nervous system of the Japanese quail (Coturnix coturnix japonica).

In the present study we detailed the distribution of GFAP-immunopositive structures within the central nervous system of the Japanese quail. Different fixation and embedding procedures were applied. The best results were obtained on frozen cryostatic sections from freshly dissected brains subsequently fixed by a short immersion in cold acetone. Immunopositive structures were observed both with immunofluorescence, and with immunoperoxidase methods. Immunoreactive cell bodies and processes were observed within the whole central nervous system, and different cell types can be identified on the basis of their topographical location and morphology. A first class of astrocytes is composed of intensely stained unipolar cells lining the inner surface of the pia mater and the large blood vessels. A second type is represented by multipolar astrocytes of variable size, provided with an irregular cell body. The last type is represented by similar elements, showing an immunonegative cell body, that can be identified only by the presence of converging processes. These three types of cells, and several isolated processes, show a differential distribution within the quail central nervous system, both in the grey and in the white matter. Present results suggest that GFAP may represent a good marker for at least part of the astroglial population in quail.

Animals↗
PubMed1991

Effects of in ovo estradiol benzoate treatments on sexual behavior and size of neurons in the sexually dimorphic medial preoptic nucleus of Japanese quail.

In male Japanese quail, the injection of estradiol benzoate (EB) in the egg causes a complete loss of the testosterone (T)-induced copulatory behavior (behavioral demasculinization). This treatment is only effective if performed before day 12 of incubation. This suggests that embryonic estrogens affect in a permanent way brain structures controlling sexual behavior. The medial preoptic nucleus (POM) is the only sexually dimorphic brain nucleus identified in quail and it is a key center for the action of T on behavior. Recent morphometric studies revealed that the dorsolateral population of neurons in the POM is sensitive to variations of plasma T levels in adult males but not in females. These effects are not observed in the medial part of the POM. This sexually differentiated feature might therefore be organized by the embryonic hormonal environment. Quail embryos of both sexes were treated with EB or received a control injection either on day 9 or on day 14 of egg incubation and the cell size in the dorsolateral and medial POM was evaluated by classical morphometric techniques. EB treatment on day 9 decreased cell size in the dorsolateral POM neurons of males but had no effect in females. No effect was also observed when the treatment was performed on day 14. The medial POM neurons were not affected. The decrease in neuronal size observed in the dorsolateral POM of males treated with EB on day 9 was correlated with their behavioral demasculinization. Some of these males showed a weak sexual behavior during the tests and in parallel had significantly larger neurons.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1991

A sex-dependent influence of testosterone on the dorso-medial neuronal population of the Japanese quail intercollicular nucleus.

The nucleus intercollicularis in quail is implicated in the control of a number of vocalizations. It is also a target structure for steroids and includes high numbers of cells containing androgen and estrogen receptors. We recently demonstrated that in another steroid target, the medial preoptic nucleus, the effects of testosterone are paralleled by significant changes in the neuronal size. A morphometrical analysis of the nucleus intercollicularis was therefore undertaken in male and female Japanese quail that were either gonadectomized or gonadectomized and treated with testosterone or left intact as controls. This showed that, in males, testosterone increases the cellular size in the dorso-medial part of the nucleus: the mean neuronal area was larger in intact and testosterone-treated males than in castrated. Such an effect was not observed in females nor in the adjacent nucleus mesencephalicus dorso-lateralis which was taken as control structure because it is devoid of steroid receptors. The changes observed in the nucleus intercollicularis of males represent a morphological marker for the cellular actions of the steroid. They could provide a useful tool to analyze the mechanisms by which testosterone activates vocalizations in male quail.

Animals↗
PubMed1991

A comparative analysis of the vasotocin and vasopressin systems in the chicken and rat hypothalamus. An immunocytochemical study.

By means of the peroxidase-antiperoxidase technique a comparative immunocytochemical study of the distribution of the vasotocin- and vasopressin-reacting system in the chicken and rat hypothalamus was carried out. In both species it is possible to distinguish, on the basis of their topographical location, three different comparable populations: The first one is situated very close to the pial surface and the optic chiasma (L1 and L2 groups in the chicken and the supraoptic nucleus in the rat). The second one is located near to the third ventricle and corresponds to the suprachiasmatic nucleus of both species and the periventricular groups of the chicken (P1, P2, and P3 groups) and the periventricular subdivision of the paraventricular nucleus of the rat. The third one is situated between the two previous populations and consists of small clusters of reacting neurons (L3 and L5 groups in the chicken and the nucleus circularis and fornicalis in the rat) and to a large cluster of reacting neurons (L4 group in the chicken and the magnocellular part of the paraventricular nucleus in rat). In the median eminence of the chicken the immunoreactive axons were located in the internal zone and the anterior part of the external zone. However in the rat, the reaction was exclusively located in the internal zone.

Animals↗
PubMed1989

[Sweet's syndrome].

The authors describe a clinical case of Sweet's syndrome in a 41-year-old man. From the clinical-instrumental tests carried out a paraneoplastic syndrome is excluded.

Adult↗
PubMed1988

Double-blind study with fenticonazole or bifonazole lotions in pityriasis versicolor.

The efficacy of fenticonazole 2% lotion was studied in patients suffering from pityriasis versicolor in a double-blind comparison with bifonazole 1% lotion, both applied once daily for three weeks. Forty-six patients were recruited and randomly allocated to one or other treatment group. Clinical and mycological examinations, performed at baseline and at weekly intervals, have shown an excellent response to both treatments. Two cases of mild transient desquamation were reported in the fenticonazole group. Fenticonazole 2% lotion appears active in the treatment of pityriasis versicolor and its efficacy is comparable to that of bifonazole.

Adolescent↗
PubMed1987

Short term treatment with ketoconazole: effects on gonadal and adrenal steroidogenesis in women.

Ketoconazole, an imidazole derivative, is a large spectrum antifungal agent. The drug is known to cause a decrease in plasma androgens and adrenal steroids in normal men; it is also an active drug in the treatment of malignant tumors of the prostate. To examine the antiandrogenic action of this drug in women, we measured several gonadal and adrenal steroids in 21 normally menstruating women before and after receiving oral ketoconazole (200 mg twice daily) for 5 days. Plasma testosterone (T) decreased from a basal level of 0.35 to 0.25 ng/ml (+/- SEM) (P less than 0.001); dihydrotestosterone (DHT) from a basal level of 190.62 +/- 23.2 to 159.75 +/- 19.43 pg/ml (P less than 0.02); dehydroepiandrosterone sulphate (DHEA-S) from 1.42 +/- 0.44 to 1.15 +/- 0.19 micron/ml (P less than 0.02). Plasma 17 beta-estradiol (E2) decreased from a basal level of 97.42 +/- 29.37 to 54.32 +/- 9.9 pg/ml (P less than 0.05). In contrast, plasma 17-OH-progesterone (17-OHP) levels increased from a basal level of 44.81 +/- 8.21 to 71.81 +/- 15.81 ng/100 ml (P less than 0.05). These results confirm that the ketoconazole blocks the conversion of progestins into androgens. The decrease in the plasma concentration of E2 suggest a direct effect of the ketoconazole on the ovary. It is likely that the effect of the drug, both at the level of the ovaries and of the adrenal gland, is dose-dependent.(ABSTRACT TRUNCATED AT 250 WORDS)

17-alpha-Hydroxyprogesterone↗
PubMed1987

Clinical experience with fenticonazole 2% formulation in the treatment of dermatomycoses and pityriasis versicolor.

Clinical efficacy of fenticonazole 2% cream has been tested on 30 patients with dermatomycoses and the 2% nebulized lotion on 10 patients with pityriasis versicolor. Treatment consisted of two topical applications of the drug for up to 5 weeks and clinical improvement and mycology were assessed at one-week intervals. Thirty-six patients (90%) were cured at the end of the 5-week period; 26 were cured from dermatomycoses and 10 from pityriasis versicolor. No recurrency/reinfection nor side-effects were encountered. The success attained by fenticonazole treatment indicates that it is a first choice drug in the therapy of superficial dermatomycoses.

Administration, Topical↗
PubMed1986

Ketoconazole: therapeutic results obtained in the district of Cagliari.

The therapeutic results of ketoconazole treatment in 61 patients affected by mycoses at various locations are reported. The mycotic conditions in these patients were: pityriasis versicolor (26), tinea cruris (14), tinea corporis (8), tinea pedis (6), kerion celsi (6) and monilial granuloma (1). Clinical and mycological cure was obtained in 56 cases (91.8%) over a mean treatment period from a minimum of 29 days (pityriasis versicolor) to a maximum of 39 days (tinea pedis) and 150 days (monilial granuloma), with a mean daily dosage of 200 mg in adults and 100 mg in children. The authors stress the high level of tolerability of the drug and its high therapeutic activity. They indicate the conditions for its use in superficial epidermomycoses and kerion celsi and note its unparalleled effect in chronic mucocutaneous candidosis.

Adolescent↗
PubMed1983

[Psoriatic arthritis: considerations on recent studies: serum beta 2 microglobulin and circulating T-gamma lymphocytes].

The results of two recent studies of our group have been reported. They regard two immunological parameters of psoriatic arthritis: the proportions of T gamma lymphocytes in peripheral blood and the beta 2 microglobulin in the serum. The data obtained in psoriatic arthritis patients have been compared to those found in normal controls and in rheumatoid arthritis patients. T gamma mean values in psoriatic arthritis were significantly lower than those present in healthy subjects and in rheumatoid patients. These last patients showed beta 2 microglobulin mean values significantly higher than those observed in normal controls and in psoriatic arthritis patients. Conversely, the mean of beta 2 microglobulin levels in psoriatic arthritis has been found to be similar to that observed in normal controls, but a superimposition in the range of individual values of these two groups with the concentrations determined in rheumatoid subjects has been found. These results seem to be of interest in relation to the immunopathogenetic mechanism of psoriatic arthritis, but are of little help in the clinical differentiation of the two rheumatological affections considered.

Arthritis↗