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Journal Article 2002; 23(Suppl 2): 14-16 PubMed PMID: 12163842 Citation  Keywords:  Humans, Light:adverse effects, Lighting, Physical Phenomena, Physics, Sunlight:adverse effects,.   

: The physical properties of light, both natural and artificial, play a significant role in its interaction with humans. Although there is a yet-to-be-explained duality between light as waves and light as photons, we do understand many of the characteristics of light that affect living things. Here I review the general history of light and its properties, especially those that affect human health....

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Journal Article 2002; 23(Suppl 2): 9-13 PubMed PMID: 12163841 Citation  Keywords:  Animals, DNA Damage, Humans, Light:adverse effects, Melatonin:metabolism, Neoplasms:etiology, Neurodegenerative Diseases:etiology,.   

: This brief review summarizes some of the biological effects of light exposure at an inappropriate time (during the normal dark period) and the potential negative physiological consequences of this light exposure. Two major systems are significantly influenced by light at night. Thus, the circadian system and melatonin synthesis are altered when light is extended into the normal dark period or when the dark period is interrupted by light. This summary reviews the potential sequelae of chronic inappropriate light exposure and the suppression of endogenous melatonin levels. Given that melatonin is a free radical scavenger and antioxidant, conditions that involve free radical damage may be aggravated by light suppression of melatonin levels. The conditions of particular interest for this review are excessive DNA damage (which potentially leads to cancer), cellular destruction in neurodegenerative diseases and aging itself. Further research should be conducted to more accurately define the potential negative impact of light at abnormal times on animal and human pathophysiology....

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Editorial 2002; 23(Suppl 2): 4-6 PubMed PMID: 12163840 Citation  Keywords:  Congresses as Topic, Humans, Neuroendocrinology:organization & administration, Societies, Medical,.   

: The international meeting Light, Endocrine Systems and Cancer--Facts and Research Perspectives was convened because recent research suggests that ubiquitous light may have more serious cancer consequences than expected. Beyond the established causal link between (over) exposure to sunlight and skin cancer, many scientists consider a causal relationship between light, endocrine systems and internal cancers as biologically plausible. To identify options to turn biological plausibility of mechanisms into true understanding and to assess the possible public health relevance we chose to bring together leading specialists from clinical, experimental laboratory and epidemiological studies of these issues to stimulate a critical, multi-disciplinary discussion of published and new results. Presentations at the symposium covered the physics of light and evolutionary aspects and provided intriguing information about chronobiology, physiology and patho-physiology of endocrine systems and carcinogenesis. Experimental and epidemiological findings on light and skin cancer, and of very recent investigations of relationships between light and internal cancers such as breast cancer were presented. The meeting concluded with a lively discussion of future research options. The symposium's essence and constructive atmosphere are captured in these proceedings [Neuroendocrinol Lett 2002 Jul;23 Suppl 2:1-104] which contain: (i) original presentation papers [Vladimir Anisimov, David Blask, Roland Böni, George Brainard, Thomas Erren, Alexander Lerchl, Sidney Perkowitz, Chris Portier, Russel Reiter, Richard Stevens, Günter Vollmer]; (ii) abstracts of oral and poster presentations; (iii) four commentaries [Charles Poole, Chris Portier, Till Roenneberg and Rob Lucas, Vladimir Anisimov and Johnni Hansen] on the presentations at the meeting and possible implications for research and public health. In our view, the biological plausibility of mechanistic links between light and hormones and cancer can serve as a unique basis for syn-disciplinary research and we expect that investigations in this area will become a higher priority research focus....

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Journal Article 2002; 23(3): 259-261 PubMed PMID: 12080289 Citation  Keywords:  Biogenic Monoamines:blood, Dopamine:blood, Epinephrine:blood, Hallucinogens:adverse effects, Humans, Hydroxyindoleacetic Acid:blood, N-Methyl-3,4-methylenedioxyamphetamine:adverse effects, Norepinephrine:blood, Psychoses, Substance-Induced, Serotonin:bloo.   

: Recreational use of the synthetic methamphetamine derivative MDMA (3,4-methylenedioxymethamphetamine), the main constituent of the illegal drug "ecstasy", has increased dramatically in recent years. The reasons for ecstasy-associated cardiovascular complications like tachycardia, arrhythmias and hypertensive crises and psychiatric symptoms like psychotic episodes are not well understood. We have measured the plasma concentrations of 5-HIAA, 5-HT, norepinephrine, epinephrine and dopamine in 159 ecstasy users and controls. Ecstasy users showed elevated resting sympathetic activity, reflected in increased norepinephrine, epinephrine and dopamine levels. The levels of these catecholamines correlated positively with the cumulative dose and also with consumption during the last 30 days and 12 months. Although it is known that significant changes in 5-HT and 5-HIAA appear in the cerebrospinal fluid in ecstasy users, we could not detect alterations in serotonergic neurotransmitters in plasma in this large sample of subjects. Thus, in the drug-free interval, ecstasy users show lowered central serotonergic activity (lowered 5-HT and 5-HIAA concentrations in CSF) along with unchanged central noradrenergic and dopaminergic activity (HVA and MHPG unchanged in CSF) and elevated peripheral noradrenergic, dopaminergic and adrenergic activity along with unchanged peripheral serotonergic activity (plasma levels). We conclude, that the data presented here could argue for a noradrenergic hyperreactivity in the drug-free interval in ecstasy users resulting from previous ecstasy consumption. Also for an association with psychotic episodes and cardiovascular complications like tachycardia, arrhythmias....

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Clinical Trial 2002; 23(3): 255-258 PubMed PMID: 12080288 Citation  Keywords:  Aged, Antineoplastic Agents:administration & dosage, Carcinoma, Renal Cell:drug therapy, Drug Therapy, Combination, Female, Humans, Injections, Subcutaneous, Interleukin-2:administration & dosage, Kidney Neoplasms:drug therapy, Lymphocyte Count, Male, Mid.   

OBJECTIVES: Recent advances in knowledge of Psychoneuroimmunology have shown that several neuroactive substances, including neurohormones and neuropeptides, may exert immunomodulatory effects. However, despite the great variety of potential neuroimmune interactions, at present we may recognize two major neuroendocrine systems exerting a physiological neuroimmunomodulatory function, consisting of the pineal gland and the brain opioid system, provided by immunostimulatory and immunosuppressive effects, respectively. Recent in human studies have demonstrated the possibility to amplify the biological activity of IL-2, the major anticancer cytokine, by pineal indoles.

MATERIALS & METHODS: The present study was carried out to draw some preliminary in human results on the possible immunomodulatory effects of the inhibition of the brain opioid activity by a long-acting opioid antagonist, naltrexone (NTX). The study was performed in 10 metastatic renal cell cancer patients, who had progressed on a previous immunotherapeutic cycle with IL-2 alone. Patients were treated with the same doses of IL-2 (6 million lU/day subcutaneously for 6 days/week for 4 weeks) plus an oral administration of NTX at a dose of 100 mg every 2 days.

RESULTS: The clinical response consisted of a partial response in 1 and a stable disease in 5 patients, whereas the other 4 patients progressed. Therefore, the percent of non-progressive disease was 6/10 (60%). Moreover, mean lymphocyte increase achieved during IL-2 plus NTX was significantly higher (P<0.05) than that obtained during the previous treatment with IL-2 alone.

CONCLUSIONS: This study shows that a blockade of the brain opioid system, which plays a physiological immunosuppressive role, may improve the anticancer effects of IL-2 in humans....

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Journal Article 2002; 23(3): 243-248 PubMed PMID: 12080286 Citation  Keywords:  Aged, Asthma:drug therapy, Circadian Rhythm, Estrogen Replacement Therapy, Female, Glucocorticoids:therapeutic use, Humans, Melatonin:metabolism, Middle Aged, Postmenopause:physiology,.   

OBJECTIVE: The aim of the study was to check if in postmenopausal women such a disease as asthma and use of hormone replacement therapy (HRT) influence daily melatonin (MEL) secretion.

MATERIAL AND METHODS: Studies were performed in 55 asthmatics (treated and not treated with glucocorticosteroids) and 20 healthy postmenopausal women (aged 48-60) before HRT and after 6 months of transdermal 17beta-estradiol and medroxyprogesterone acetate treatment (cyclical method). During the circadian study blood samples for the measurement of MEL were collected every 3 hours during the day. MEL concentrations were assessed with the use of RIA methods. Statistical analysis of the circadian rhythm was performed with the use of cosinor test according to Halberg et al.

RESULTS: Existence of daily rhythm of MEL secretion was shown in all studied groups, before as well as after HRT. A significant decrease of mesor and amplitude's rhythm was observed in the group of women with asthma treated with glucocorticosteroids (GC) before and after HRT use in relation to women not treated with GC and the control group. Secretion of MEL in these patients was lower at nocturnal hours. A significant decrease of mean daily MEL secretion in relation to values before HRT use was shown in all groups.

CONCLUSIONS: Asthmatic postmenopausal women treated with GC show lowered circadian secretion of melatonin as a consequence of lowering its secretion at nocturnal hours. Hormonal replacement therapy causes a decrease of daily melatonin secretion in healthy as well as asthmatic women, not disturbing circadian rhythm of this hormone's secretion....

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Journal Article 2002; 23(3): 239-242 PubMed PMID: 12080285 Citation  Keywords:  Adenocarcinoma:metabolism, Aged, Circadian Rhythm, Colorectal Neoplasms:metabolism, Female, Humans, Male, Melatonin:blood, Middle Aged, Radioimmunoassay,.   

OBJECTIVE: The aim of the study was pineal gland function assessment on the base of daily rhythm study and mean daily melatonin (MEL) concentrations in serum in patients with colorectal carcinoma.

MATERIAL AND METHODS: Studies were performed in 12 women at the age of 63.17+/-5.90 years and 21 men aged 58.95+/-11.32 years with large intestine adenocarcinoma. The control group consisted of 28 healthy volunteers at comparable age. During the circadian study blood samples for the measurement of melatonin (MEL) were collected every 4 hours during 12 h. MEL concentrations were assessed with the use of RIA methods. Statistical analysis of circadian rhythms of MEL was carried out with the use of cosinor method according to Halberg.

RESULTS: Existence of daily rhythm of MEL secretion was shown in all studied groups. A significant decrease of amplitude of rhythm and secretion of MEL at nocturnal hours in comparison with the control group was shown in the group of women with large intestine carcinoma. A significant decrease of mesor value and amplitude of MEL rhythm as a consequence of decrease of MEL secretion at nocturnal and morning hours was observed in the group of ill men.

CONCLUSIONS: Decrease in melatonin circadian rhythm amplitude as a consequence of its lowered nocturnal secretion occurred in all patients with colorectal carcinoma. Abnormalities in daily rhythm of melatonin secretion were more intensified in men with large intestine carcinoma, which leads to suppression of mean daily hormone concentration....

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Journal Article 2002; 23(3): 226-230 PubMed PMID: 12080283 Citation  Keywords:  Adult, Aged, Brain:physiopathology, Cognition, Diabetes Mellitus, Type 2:physiopathology, Diabetic Retinopathy:physiopathology, Event-Related Potentials, P300, Female, Humans, Hypoglycemia:physiopathology, Male, Middle Aged,.   

OBJECTIVES: The purpose of this study was to evaluate the ERP P300 in non insulin dependent diabetes mellitus (NIDDM) patients without cognitive impairment and the relationship with clinical variables, the presence of retinopathy and previous hypoglycemic episodes.

METHODS: NIDDM patients (N=44) without evidence of cognitive impairment and controls (N=17) were studied clinically and with ancillary exams and the ERPs P300 were recorded. Patients were examined clinically and with the Folstein Mini-Mental Examination (MMSE) for cognitive function and all patients showed a score higher than 26 (maximal value=30). Previous hypoglycemia was evaluated through a questionnaire establishing the number of episodes and the symptoms of hypoglycemia in a scale scoring from zero to 15.

RESULTS: ERP P300 latencies were significantly higher in NIDDM patients than in controls (p<0.03). ERP P300 measures were significantly related to age (Pearson, p<0.01) and not to metabolic variables, disease duration or the presence of retinopathy. Severity of hypoglycemia was not associated to ERP P300 latency.

CONCLUSIONS: Our study supports the evidence that NIDDM patients, without signs of nervous system involvement, have ERP P300 alterations and this is not related to retinopathy, metabolic variables or previous hypoglycemic episodes. Chronic hyperglycemia may alter brain glucose transport and increase tolerance to hypoglycemia effects in the nervous system....

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