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N Fabris

Publications and source records attributed to N Fabris.

136 records · Page 8Linked to original sources
PubMedDate not supplied

Increased immunological efficiency in young mice by short-term treatment with L-thyroxine.

Treatment of young mice with L-thyroxine increases their capacity to form hemolytic plaques after sheep erythrocyte immunization. Such an increment is independent from the quantity of antigenic challenge, from sex and strains variations and from the temporal relationship between timing of hormonal treatment and antigenic challenge. The increment seems to depend on an increased number of both T and B reactive cells, rather than on an augmented proliferation rate of antigen triggered cells. The thyroxine induced increase of T reactive cells requires the presence of a functional thymus. These data suggest that the maximal immune response obtained under physiological conditions does not correspond to the maximal potentiality which can be expressed through appropriate manipulation of the internal microenvironment and further confirm the relevance that thyroxine may have as an immunostimulant agent.

Adjuvants, Immunologic↗
PubMedDate not supplied

Neuroendocrine-immune interactions: a theoretical approach to aging.

Among the systemic theories of aging, both a 'nervous-neuroendocrine' and an 'immune' hypothesis have been proposed. The discovery of the complex interactions working among the neuroendocrine and the immune systems suggests the revision of the systemic theories of aging, particularly in the light of the recent evidence that some age-associated alterations in the neuroendocrine and in the immune systems are mutually interdependent even at very old age, as revealed by the fact that experimental manipulation of one of the two systems modifies and sometimes restores the function of the other one. These findings clearly demonstrate that at least some of the age-related alterations of the nervous, neuroendocrine and immune networks are not per se intrinsic and irreversible and that the definition of the temporal priority in the age-related deterioration is rather is rather difficult to be assigned to one or other homeostatic apparatuses. As an alternative to pure, either 'neuroendocrine' or 'immune', theories of aging, it has been hypothesized that, due to the strict interactions existing among the nervous, neuroendocrine and immune systems during the whole life of the organism, it is the disruption of such interactions in old age which is responsible for most of the age-associated dysfunctions (Fabris, 1986). This theoretical approach is discussed in the light of a stochastic or single-cause oriented hypothesis of aging.

Journal Article↗
PubMedDate not supplied

Plasticity of neuroendocrine-thymus interactions during aging.

Thymic regrowth and reactivation of thymic endocrine activity may be achieved even in old animals by different endocrinological or nutritional manipulations such as, (a) intrathymic transplantation of pineal gland or treatment with melatonin, (b) implantation of a growth hormone (GH) secreting tumor cell line or treatment with exogenous GH, (c) castration or treatment with exogenous luteinizing hormone-releasing hormone (LH-RH), (d) treatment with exogenous thyroxine or triiodothyronine, and (e) nutritional interventions such as arginine or zinc supplementation. These data strongly suggest that thymic, involution is a phenomenon secondary to age-related alterations in neuroendocrine-thymus interactions and that it is the disruption of such interactions in old age that is responsible for age-associated dysfunction. With regard to the mechanisms involved in hormone-induced thymic reconstitution, it is at present, difficult to draw any definitive conclusions. The effect of GH, thyroid hormones, and LH-RH may be due to the presence on thymic epithelial cells supposed to produce thymic peptides, of the specific hormone receptors. Melatonin or other pineal factors may also act through specific receptors, but experimental evidence is still lacking. The role of zinc, whose turnover is usually reduced in old age, is diverse. The effects range from the reactivation of zinc-dependent enzymes, required for both cell proliferation and apoptosis, to the reactivation of thymulin, a zinc-dependent thymic hormone. The role of zinc may even be more crucial. According to recent preliminary data obtained both in animal and human studies, it appears that the above reported endocrinological manipulations capable of restoring thymic activity in old age, may act also by normalizing the altered zinc pool.

Aging↗
PubMedDate not supplied

Zinc affects the metabolism of thyroid hormones in children with Down's syndrome: normalization of thyroid stimulating hormone and of reversal triiodothyronine plasmic levels by dietary zinc supplementation.

Levels of circulating thyroid stimulating hormone (TSH), tetraiodothyronine (T4), 3,5,3'-triiodothyronine (T3), and 3,3',5' triiodothyronine (reversal T3 or rT3) were measured in 25 children with trisomy of chromosome 21, also known as Down's syndrome (DS), and in 14 normal children. In subjects with DS TSH levels were increased, while plasmic levels of rT3 were decreased. No alteration in T3 and T4 levels was observed. Before zinc supplementation, plasmic levels of zinc and thymulin, a zinc dependent thymic hormone, were significantly decreased in DS children. After four months of dietary supplementation with zinc sulphate, a normalization of plasmic zinc, thymulin and TSH levels was observed. Plasmic levels of rT3 significantly increased, and after zinc treatment no difference was detectable between DS children and normal children. Clinical evaluation of the health status of DS children showed that zinc supplementation decreased the incidence of infectious diseases and improved school attendance. Thus, the increased efficiency of the immune system and the normalization of some endocrine parameters by zinc supplementation suggests that zinc deficiency may play a crucial role in some of the pathological manifestations associated with the syndrome, such as infections and malfunctioning of the thyroid gland.

Adolescent↗
PubMedDate not supplied

Immunitary system in pregnancy hypertension.

Several Authors demonstrate changes in maternal immune system in women with pregnancy induced hypertension (PIH). In this study peripheral mononuclear cells were isolated in fifteen primigravid women with PIH and tested with monoclonal antibodies Leu 4, Leu 3, Leu 2 and Leu 7; in four women were studied monoclonal antibodies anti-Tac. The results were compared with a normotensive pregnant control group. T helper and T suppressor were increased but showed no statistical difference. The difference was statistically significant only for th NK cells. Tac antigen was expressed only on the Leu 3 induce subset. The PIH occurs because of a failure of maternal immune system.

Antibodies, Monoclonal↗
PubMedDate not supplied

[Thymic hormone treatment of acute and chronic respiratory infections in the elderly].

Respiratory infections are particularly frequent in aged subjects and cause severe and often inauspicious complications) such as compromised cell-mediated immunity. Preliminary data suggest thymopentin treatment in a population of elderly subjects affected by relapses of bronchial disease. The effects of the therapy are adequately monitored controlling immunologic parameters.

Acute Disease↗