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Letter 2002; 23(4): 287-288 PubMed PMID: 12195227 Citation  Keywords:  Animals, Genes, Fungal:physiology, Homosexuality, Humans, Pheromones:physiology, Rodentia, Vomeronasal Organ:physiology, Yeasts:physiology,.   

: Pheromones and their receptors are the molecules used by very different organisms in order to join two haploid cells. It happens evidently in yeast, since the two blending haploid cells are also the two mating organisms, whereas in rodents pheromone receptors are the triggers of the vomeronasal system which, supervising sexual behaviors, is responsible for copulation and therefore for fertilization. The debate is still open about the real significance of pheromones in humans but a working vomeronasal organ, able to recognize pheromones of the same sex, could be the simplest biological explanation of homosexuality. This hypothesis is discussed and connected with some well known experimental data....

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Journal Article 2002; 23(4): 281-285 PubMed PMID: 12195225 Citation  Keywords:  Anti-Inflammatory Agents, Non-Steroidal:adverse effects, Aspirin:adverse effects, Asthma:chemically induced, Humans, Neurosecretory Systems:pathology,.   

: Available clinical data on aspirin-sensitive asthma (ASA) indicate that ASA patients have certain disturbances in the nervous, endocrine, immune and other body systems. It has been found that such patients have a lower melatonin (MT) production in daytime, a pathology of the platelet membrane-receptor complex, and a pathological response to exogenic MT and acetylsalicylic acid. A hypothesis has been suggested in which ASA is considered as apudopathy caused by dysfunction of MT-producing cells. The decreased MT production and the disturbed cell sensitivity to MT lead to pathological changes in individual organs and functional systems. As a result, there is an enhanced lipid peroxidation, an excessive production of reactive oxygen radicals, and a reduced inhibitory action of MT on the 5-lipoxygenase and NO-synthase activities. The lower MT content also results in an intense aggregation of platelets, activating these cells and increasing the production of leukotrienes and nitric oxide. These changes disturb the pulmonary microcirculation, causing the bronchial obturation syndrome even in patient who do not take aspirin or other nonsteroidal anti-inflammatory drugs. The lower basic production of MT is also responsible for a lower content of its metabolite-endogenic acetylsalicylic acid, thereby increasing the sensitivity of melatonin-producing cells, in particular of platelets, to this acid. So, even minimal aspirin doses inhibit the activity of COX-1, which shunts the already abnormal metabolism of arachidonic acid. This, in turn, leads to a greater production of leukotrienes and, hence, to a severe course of the disease. This hypothesis has become the basis for a new pathogenetic approach to the treatment of ASA patients by correcting the melatonin content with peptide bioregulators--the epiphysis extracts--Epithalamin and Epiphamin....

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Journal Article 2002; 23(4): 273-280 PubMed PMID: 12195224 Citation  Keywords:  Animals, Humans, Pituitary Gland, Posterior:physiology, Receptors, Purinergic:physiology,.   

: The neurohypophysis is an original model of the CNS secretory system releasing vasopressin (AVP) and oxytocin (OXT), two neuropeptides hormones synthesized by the magnocellular neurons of the hypothalamus. Specific patterns of action potentials originating from cellular bodies of magnocellular neurons control the release of AVP and OT, but intra-neurohypophysis regulations do modulate the neuropeptides release. There is now good evidence for the effects of extracellular purines in the control of neurohypophysial secretion. This paper brings together evidence for the multiple, intricate actions of purines in the extracellular space of the neurohypophysis. It covers four main points. First, the activity-dependent release of endogenous ATP in the neurohypophysis. Second, the action of ATP on both neuronal and non-neuronal compartments of the neural lobe. Third, the termination of ATP positive feedback by ecto-nucleotidases. And finally the possible involvement of adenosine in the regulation of neurohypophysial secretion and glial plasticity. The data suggest that ATP and adenosine are physiological modulators of the release of neurohypophysial peptides by acting directly on nerve terminals and indirectly on neurohypophysial astrocytes. Since purinergic receptors are widespread in nervous and endocrine systems, the neurohypophysis appears as an useful model for studying the role of purines in the regulation of stimulus-secretion coupling and neuron-glia interactions. The feedback mechanisms found in the neurohypophysis could be ubiquitous, occurring throughout the central nervous system and in other secretory systems....

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Editorial 2002; 23(4): 271-272 PubMed PMID: 12195223 Citation  Keywords:  Humans, Neuroendocrinology:trends, Periodicals as Topic:trends,.   

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Congresses 2002; 23(Suppl 2): 4-104 PubMed PMID: 12163856 Citation  Keywords:  Animals, Endocrine System:physiology, Humans, Light:adverse effects, Neoplasms:etiology,.   

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Congresses 2002; 23(Suppl 2): 84-87 PubMed PMID: 12163855 Citation  Keywords:  Animals, Humans, Light:adverse effects, Neoplasms:epidemiology, Neurosecretory Systems:physiology, Risk Factors,.   

: The International Symposium "Light, Endocrine Systems and Cancer" was held on May 2-3 at Cologne University, Germany. The symposium was organized by Professor Claus Piekarski and Dr. Thomas C. Erren, Institute and Polyclinic for Occupational and Social Medicine. The main goal of the symposium was to evaluate the epidemiological and experimental data on the effect of the exposure to light-at-night on cancer risk and to indicate the main directions of future research in the field. The symposium covered also the mechanisms and epidemiology of skin cancer which, however, are not included in the present summary....

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Editorial 2002; 23(Suppl 2): 82-83 PubMed PMID: 12163854 Citation  Keywords:  Circadian Rhythm:physiology, Humans, Light:adverse effects, Neoplasms:epidemiology, Neurosecretory Systems:physiology, Risk Factors,.   

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Editorial 2002; 23(Suppl 2): 79-81 PubMed PMID: 12163853 Citation  Keywords:  Animals, Humans, Light:adverse effects, Neoplasms:epidemiology, Neurosecretory Systems:physiology, Risk Factors,.   

: A conference was held at the University of Cologne on May 2-3, 2002, to discuss the strength-of-the-evidence supporting a linkage between light, endocrine systems and cancer. This overview of the conference is intended to summarize some of the key elements of the conference and to indicate both conclusions and research gaps identified by this reviewer....

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