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Journal Article 2005; 26(3): 193-195 PubMed PMID: 15990720 Citation  Keywords:  Adrenal Cortex:cytology, Animals, Biological Clocks:physiology, Cell Aging:physiology, Humans,.   

: It is well known that plasma levels of dehydroepiandrosterone (DHEA), a steroid hormone secreted by zona reticularis (ZR) of the adrenal cortex, reach the maximal values in the third decade of life and then gradually decline with age. Moreover, the DHEA deficiency is probably responsible for several functional disturbances connected with aging. It was also found that ZR reaches its definitive volume at puberty and undergoes selective atrophy during the aging. Thus, the decline of DHEA may be a simple consequence of ZR atrophy in aged subjects. A hypothesis presented here attempts to explain the mechanism of the age-related ZR atrophy and is based on the adrenal cortex cell kinetics. In the adrenal cortex the cell proliferation indices are lower when we pass from zona glomerulosa (ZG) to the inner zones and are the lowest in ZR. In contrast, the apoptotic index is the highest in ZR. It is suggested that adrenocortical cells renew from the progenitor cells located in ZG /zona fasculata boundary and /or in subcapsular layer. These cells migrate centripetally undergoing the subsequent steps of differention and consecutive divisions - and - if not die en route - reach the most central localization in ZR. In consequence, ZR includes the "oldest" adrenocortical cells which probably in majority reached the "Hayflick's number" and cannot divide. This results in the preponderance of apoptosis over proliferation leading to progressive ZR atrophy followed by a decline of secretion of ZR-derived steroid hormones....

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Clinical Trial 2005; 26(1): 39-42 PubMed PMID: 15726018 Citation  Keywords:  Aging:physiology, Child, Preschool, Chorionic Gonadotropin:administration & dosage, Cryptorchidism:drug therapy, Humans, Infant, Injections, Intramuscular, Male, Scrotum:pathology,.   

OBJECTIVES: To evaluate the efficacy of hCG therapy on retractile testis in various testicular locations and age groups.

SETTING AND DESIGN: This study comprised 123 boys whose diagnosis were retractile testis with scrotal base, high scrotal and superficial inguinal localizations with an average age of 4,2 (1-8) years.

METHODS: 123 boys with retractile testes were given a total dose of 9000 hCG and its effect on scrotal base, high scrotal and superficial inguinal located testes were evaluated after 2 weeks and 6 months of completing hCG course. The patients were evaluated in four age groups such as less than 2 years of age, between 2-4, 4-6 years and more than 6 years of age and the response rates were also noted in these age groups.

RESULTS: In unilateral cases, the response in base, high scrotal and superficial inguinal levels were found as 100%, 83,3%, 72,7% respectively where as these rates were found as 100%, 92,6%, 76,3% respectively in bilateral cases after 2 weeks of hCG therapy. The response rates in less than 2 year old group, 2-4, 4-6 and more than 6 years group were found as 0%, 80%, 78,7%, 100% respectively in unilateral cases and 33,3%, 90%, 86,9% and 83,3% respectively in bilateral cases. After 6 months, reascend was observed in 12,4% in unilateral group and 6,7% in bilateral group.

MAIN FINDINGS: 72,7-100% of retractile testes respond to hCG administration with the highest response in the age of more than six year group.

CONCLUSION: High response rates observed in retractile testes after hCG therapy in more than 2 years old age group indicate that hCG must be given as a primary treatment in retractile testes and orchiopexy for the failures. Also patients must be followed up closely for reascend cases....

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Journal Article 2005; 26(1): 25-28 PubMed PMID: 15726015 Citation  Keywords:  Aging:physiology, Animals, Animals, Newborn, Brachial Plexus:physiology, Electrophysiology, Entropy, Male, Neurons, Afferent:physiology, Pain:etiology, Rats, Rats, Wistar, Rhizotomy, Self Mutilation:etiology,.   

OBJECTIVES: The aim of the study was to describe the development of self-mutilation after extensive dorsal rhizotomy of the brachial plexus performed during early ontogeny in rats.

SETTINGS AND DESIGN: The rhizotomy was performed in three groups of rats according to the central nervous system maturation: infant, young, and adult. After the surgery the occurrence of self-mutilation behavior was compared. Rats from the infant group and non-mutilating deafferentated rats from the adult group underwent extracellular recordings from intralaminar thalamic neurons. Interspikes intervals of the records were compared by means of chaodynamic methods.

RESULTS: In the infant group self-mutilation did not develop at all. Among the young group self-mutilation developed in 40% of rats and consisted of superficial wounds in all cases. In adult self-mutilation appeared in 80% rats and consisted of both superficial wounds (75%) and amputation (25%). In the newborn group and the deafferentated adult group without any signs of self-mutilation means of the parameters were not significantly different and were significantly lower than those of intact adult rats.

MAIN FINDINGS: 1. Self-mutilation does not develop after the rhizotomy in the infant rats. 2. Neurons behave in chaotic way in adult as well as in young animals. 3. Chaodynamic parameters do not differ between infant and adult rats without any signs of self-mutilation.

CONCLUSIONS: The results suggest that development of self-mutilation behavior in rats strongly depends on the ontogenetical period of nervous system injury, and that mature nervous system is required for the development of described pathological behavior....

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Journal Article 2003; 24(5): 329-333 PubMed PMID: 14647006 Citation  Keywords:  Aged, Aging:physiology, Cells, Cultured, Euchromatin:drug effects, Heterochromatin:drug effects, Hot Temperature, Humans, Lymphocytes:cytology, Oligopeptides:pharmacology, Protein Denaturation, Ribosomal Proteins:genetics, Transcriptional Activation:drug .   

UNLABELLED: OBJECTIVES and design. We have studied the effect of synthetic peptide Epitalon on the activity of ribosomal genes, denaturation parameters of total heterochromatin, polymorphism of structural C-heterochromatin and the variability of facultative heterochromatin in cultured lymphocytes of persons aged 76-80 years.

RESULTS: The obtained data demonstrate that Epitalon induces the activation of ribosomal genes, decondensation of pericentromeric structural heterochromatin and the release of genes repressed due to the age-related condensation of euchromatic chromosome regions.

CONCLUSIONS: Epitalon has shown its ability to activate chromatin by modifying heterochromatin and heterochromatinized chromosome regions in the cells of older persons....

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Journal Article 2003; 24(3-4): 151-160 PubMed PMID: 14523349 Citation  Keywords:  Aging:physiology, Attention:physiology, Brain:growth & development, Consciousness Disorders:psychology, Electroencephalography, Electrophysiology, Eye Movements:physiology, Female, Gravitation, Humans, Learning:physiology, Male, Sleep:physiology,.   

: The interest in studying the brain electrical activity as a function of the development of intelligence has been spurred by the need to understand how the brain responds to environmental information. The description of sleep in mentally retarded children reveals deviant patterns of the EEG-spindles and of the eye movement activity (REM sleep) when compared to normal children. The patterns may be considered as a valuable index of mental function. According to experimental evidence, the distribution of the eye movements of sleep appears either as random or ordered. The latter are altered in the mentally handicapped in whom the appearance out of chaos, of the order which is needed for intelligence and memory to function, is altered. The sleep signs are redundant as from birth. Their pattern is also related to the psychomotor development of the infant. If their distribution remains random, or appears in long uninterrupted sequences of waves as in epilepsy, intelligence does not develop. A similar strategy appears to function in the foetus when nature organizes the structures that will lead to the development of intelligence. The eye movement patterns of sleep change in the pregnant women as a function of term and resemble those of premature babies of a similar gestational age. They also change as a function of the menstrual cycle and more generally as a function of age. The hypothesis that attention is the diurnal equivalent of REM sleep is discussed. Attempts at modelling the eye movement patterns of REM sleep as a function of near zero gravity environments have been made. 1) By means of a Montecarlo simulation using the semi Markov model during the Spacelab 1 flight. 2) With the method of the single and multiple g-phase transition analysis of the strange attractor dimension (d) during parabolic flights. The implication of the latter for the neural processes involved in learning is that the central nervous system can preserve intact, from input to output, over a period of several days, all the information it receives 3) The relation between spindles and eye movements has also been viewed by a quantum approach which is another medium between the information and the way of describing it....

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Journal Article 2002; 23(4): 299-302 PubMed PMID: 12195230 Citation  Keywords:  Adult, Aged, Aging:physiology, Brain:physiology, Homosexuality, Male, Humans, Male, Middle Aged, Sex Characteristics, Sexual Behavior:physiology, Surveys and Questionnaires,.   

OBJECTIVES: The current study was designed to test a neurohormonally based theory of sexual orientation and preferred partner characteristics in homosexual men. The theory holds that the brains of homosexual men are masculinized and feminized directing attraction to targets younger and more masculine than self, and the brains of homosexual adolescents are incompletely masculinized and feminized directing attraction to targets older and more masculine than self.

METHODS: Ninety-six homosexual men completed questionnaires that asked them to rate morphological and behavioral characteristics associated with ethologically relevant indicators of masculinity. The participants made ratings for themselves as adolescents and adults, their current partners and idealized partners as adults, and their idealized partners as adolescents.

RESULTS: Results of within-subjects multivariate analyses of variance supported most of the hypotheses. Participants as adults rated their idealized partners as more masculine than themselves and their real partners on five measures: height, weight, muscle development, facial hair, and sexuality. As adolescents they indicated a preference for males older and more masculine than self. The participants in adulthood did not show the predicted preference for partners younger than themselves.

CONCLUSION: The increased ratings of sexuality for self from adolescence to adulthood support the contention that some additional masculinization of the brain may occur with aging. The increased ratings of body size for the idealized target from adolescence to adulthood keeps the target more masculine then self across developmental periods. This phenomenon is consistent with the speculated feminization of the brain at both periods and its effects on partner preferences....

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Journal Article 2002; 23(Suppl 1): 14-16 PubMed PMID: 12019345 Citation  Keywords:  Aging:physiology, Animals, Circadian Rhythm:physiology, Humans, Melatonin:physiology, Pineal Gland:physiology,.   

: Although many theories relating the pineal secretory product melatonin to aging have been put forward, the role of this agent in the aging process is not clear. However, there are several reasons to postulate a role for melatonin in this process. Melatonin levels fall gradually over the life-span. Melatonin is a potent free radical scavenger. Melatonin deficiency is related to suppressed immunocompetence. In at least one animal model melatonin supplementation increased life-span although several other studies have failed. The aging process is multifactorial, and no single element seems to be of basic importance. It seems, however, that although melatonin can not be univocally recognized as a substance delaying aging, some of its actions may be beneficial for the process of aging. However, the precise role of melatonin in the aging process remains to be determined....

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Journal Article 2002; 23(1): 49-53 PubMed PMID: 11880862 Citation  Keywords:  Aging:physiology, Animals, Circadian Rhythm, Freund's Adjuvant:administration & dosage, Hydroxyindoleacetic Acid:metabolism, Injections, Subcutaneous, Male, Melatonin:metabolism, Norepinephrine:metabolism, Pineal Gland:metabolism, Rats, Rats, Wistar, Sero.   

OBJECTIVES: This study was performed to search for changes in rat pineal function attributed to age and immunization with Freund's adjuvant.

METHODS: Young (2 months) and old (18-20 months) Wistar rats were injected s.c. with Freund's adjuvant or its vehicle. Eighteen days later, at the acute phase of arthritis, pineal concentration of serotonin (5-HT), 5-hydroxyindoleacetic acid (5-HIAA), norepinephrine (NE) and melatonin was measured by high pressure liquid chromatography at 4 different time intervals throughout the nocturnal activity span.

RESULTS: Old rats had the lowest pineal 5-HT and 5-HIAA content, the decrease in 5-HIAA exceeding that of 5-HT; consequently, old rats had the lowest 5-HIAA/5-HT ratio, an index of pineal 5-HT turnover. Although immunization did not affect globally pineal 5-HT or 5-HIAA levels, significant interactions "immunization x age" and "immunization x time" were found, i.e., immunization augmented pineal 5-HT content at the beginning of the activity span in young rats and at second half of the activity span in young and old rats, and increased pineal 5-HIAA concentration in young rats at the second part of the activity span only. Freund's adjuvant treatment increased pineal 5-HT turnover exclusively in old rats, an effect mainly seen during the second part of the activity span. Old rats exhibited the lowest pineal NE and melatonin levels, immunization further depressing them.

CONCLUSION: The effect of immunization with Freund's adjuvant on a number of pineal pre- and postsynaptic parameters are age-dependent....

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