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Journal Article 2003; 24(5): 355-380 PubMed PMID: 14647013 Citation  Keywords:  Circadian Rhythm, Epilepsy:physiopathology, Humans, Models, Biological, Myocardial Infarction:physiopathology,.   

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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(5): 321-324 PubMed PMID: 14647004 Citation  Keywords:  Adult, Coitus, Humans, Klinefelter Syndrome:blood, Male, Sexual Dysfunction, Physiological:blood, Testosterone:blood, Varicocele:blood,.   

OBJECTIVES: The aim of our study is to assess the relationship between serum testosterone levels and the coital activity in groups of married men with Klinefelter's syndrome and in men with a varicocele investigated for marital infertility. These are compared with a group of somatosexually well developed men with a normozoospermia and adequate sexual life.

SUBJECT AND METHODS: The serum testosterone levels were assessed in 77 patients with Klinefelter's syndrome (mean age 31 years, SD 5.78), 58 men with a varicocele (mean age 30.5 years, SD 5.80) and 85 healthy men with normal spermiological values (mean age 32.7 years, SD 6.31). The frequency of sexual intercourse in their marriage was assessed by interview.

RESULTS: We found that, although their serum testosterone levels were significantly lower (p < 0.01), the coital activity in both groups with somatosexual disorders did not significantly differ from the group of men with normal semen parameters. The coital activity in the group of men with Klinefelter's syndrome decreased after 35 years of age, before any decrease in serum male sex hormone levels occurred.

CONCLUSION: Statistical analysis revealed that coital activity did not correlate with testosterone levels, but correlated significantly with age. A possible interpretation of the data is that Mother Nature ensues the survival of species by the production of not only a redundant amount of spermatozoids, but also of male sex hormones....

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Journal Article 2003; 24(5): 314-320 PubMed PMID: 14647003 Citation  Keywords:  Animals, Bone Density, Female, Mandible:diagnostic imaging, Rats, Rats, Wistar, Superior Cervical Ganglion:surgery, Sympathectomy, Tomography, X-Ray Computed, Tooth Eruption:physiology,.   

OBJECTIVE: To assess the effect of local sympathectomy on mandibular bone during tooth eruption in rats.

METHODS: The effect of a unilateral superior cervical ganglionectomy (Gx) on morphometry of ipsi- and contralateral mandible and volumetric bone density (as assessed by peripheral computed tomography) was examined 30 days after surgery.

RESULTS: Only a few mandibular morphometric parameters decreased significantly after denervation in rats subjected to a unilateral Gx and a contralateral sham-operation. Mandibular volumetric bone density decreased significantly after sympathetic denervation. In a second experiment, carried out under conditions of unilateral unimpeded eruption of incisors performed ipsilaterally or contralaterally to a unilateral Gx, a significant interaction "denervation x type of eruption" was found for most morphometric parameters. Further analysis indicated higher morphometric indexes in denervated mandibles than in the innervated ones under impeded incisor eruption conditions, and lower morphometric indexes in denervated mandibles than in the innervated ones under unimpeded incisor eruption conditions. Unimpeded eruption augmented total volumetric bone density providing the innervation was intact and caused opposite effects on cortical volumetric bone density in the presence of innervation (increase) or absence of innervation (decrease). Trabecular volumetric bone density decreased significantly after sympathetic denervation.

CONCLUSION: The results support a role of the sympathetic nervous system in the regulation of bone remodeling....

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Journal Article 2003; 24(5): 293-303 PubMed PMID: 14647000 Citation  Keywords:  Animals, Humans, Oxidative Stress:physiology, Pineal Gland:physiology, Thyroid Diseases:metabolism, Thyroid Gland:metabolism,.   

: Reactive oxygen species (ROS) play an important role in physiological processes, but - when being in excess - ROS cause oxidative damage to molecules. Under physiological conditions, the production and detoxification of ROS are more-or-less balanced. Also in the thyroid, ROS and free radicals participate in physiological and pathological processes in the gland. For example, hydrogen peroxide (H2O2) is crucial for thyroid hormone biosynthesis, acting at different steps of the process. Additionally, H2O2 is believed to participate in the Wolff-Chaikoff's effect, undergoing in conditions of iodide excess in the thyroid. Much evidence has been accumulated indicating that oxidative stress is involved in pathomechanism of thyroid disease, e.g., Graves' disease, goiter formation or thyroid cancer. Melatonin (N-acetyl-5-methoxytryptamine) - the main secretory product of the pineal gland - is a well-known antioxidant and free radical scavenger, widely distributed in the organism. Mutual relationships between the pineal gland and the thyroid have - for a long time - been a subject of intensive research. The abundant to-date's evidence relates mostly to the inhibitory action of melatonin on the thyroid growth and function and - to a lesser extent - to the stimulatory effects of thyroid hormones on the pineal gland. It is highly probable that under physiological conditions melatonin and, possibly, other antioxidants regulate ROS generation for thyroid hormone synthesis. We believe that melatonin may protect against extensive oxidative damage in the course of certain thyroid disorders or in case of a harmful action of some external factors on the thyroid. Thus, oxidative damage and the protective action of antioxidants, melatonin included, may occur during both physiological and pathological processes in the thyroid, however, this assumption, requires further studies....

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Journal Article 2003; 24(5): 283-292 PubMed PMID: 14646999 Citation  Keywords:  Cytokines:physiology, Humans, Neuroimmunomodulation:physiology, Neurosecretory Systems:immunology, Stress, Psychological:immunology, Time Factors,.   

OBJECTIVES: Previously, a large number of studies reported that psychological stress and psychiatric illness reduces immune responsiveness. However, it turned out that stress reduces immune responsiveness is an oversimplified statement because the interactions between central nervous system, endocrine system and the immune system are undoubtedly complex. Therefore, this study aims in reviewing mental stress models (e.g. brief and written examination stress as subacute and acute type of stressor) that have been utilized to understand the effect of stress on the neuroendocrine and immune systems.

METHODS: The published findings from human mental stress models on catecholamines, cortisol, prolactin levels and on T helper (Th) 1 and 2-induced cytokines are presented and discussed with respect to the in vitro and in vivo effects of glucocorticoids, catecholamines, and prolactin on the induction of cytokines.

RESULTS: This review shows evidence that short-time (minutes) or preparation to a written examination, in those students who are stressed, induces the production of proinflammatory cytokines which may be related to Th1 response. However, longer mental stress (days) causes dysregulation in the immune function by shifting the cytokine response to Th2 response.

CONCLUSIONS: The outcome from neuroendocrine and immune function prior to, following and after mental stress depends on multiple variables most importantly on the amount of stress, exposure time, coping behavior and adjustment of the individual. A few minutes of stress may improve immune performance but longer times of mental stress have detrimental effects that may lead to loss of immune integrity. Furthermore, studies on stress and common heath problems are necessary to increase our knowledge and understanding of the mechanisms responsible for producing neuroendocrine-induced immune changes in health and common diseases....

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Journal Article 2003; 24(3-4): 269-273 PubMed PMID: 14523369 Citation  Keywords:  Adenocarcinoma:pathology, Animals, Cell Nucleus:ultrastructure, Circadian Rhythm:physiology, Colonic Neoplasms:pathology, Male, Mice, Mice, Inbred Strains, Neoplasm Transplantation, Organelles:ultrastructure, Pineal Gland:cytology,.   

OBJECTIVES: Relationship between the pineal gland and neoplastic disease has been repeatedly shown in many both experimental and clinical studies. However, morphological studies of the pineal gland in animals with experimentally-induced tumors are rare. Therefore, we decided to investigate the ultrastructure of pinealocytes in mice with implanted Colon 38 adenocarcinoma.

MATERIAL AND METHODS: Male adult B6D2F1 mice were used in this study. The animals were divided into two groups. Eight mice were subcutaneously implanted with Colon 38 cell suspension, whereas the other eight intact animals served as controls. Three weeks after tumor implantation four animals from each group were sacrificed by spinal cord dislocation at 12:00 h or 24:00 h. The pineal glands were removed and processed for electron microscopic studies. The cross-sectional areas of the pinealocyte and its nucleus, and relative volume of mitochondria, Golgi apparatus, lysosomes, granular endoplasmic reticulum, and lipid droplets, as well as the number of dense-core vesicles were estimated using a digital analyzer connected on-line to IBM-PC computer. Statistical analysis of the data was performed using Student's t-test and Snedecor F test.

RESULTS: In the pineal glands of the tumor-bearing animals killed during the daytime diminished size of pinealocytes and their nuclei, decreased relative volume of granular endoplasmic reticulum, lysosomes, and lipid droplets as well as decreased number of dense-core vesicles were observed. On the contrary, the relative volumes of mitochondria and Golgi apparatus were increased in these animals. In the tumor-bearing animals killed at night, however, increased cross-sectional areas of pinealocytes, and decreased number of dense-core vesicles were observed.

CONCLUSIONS: The results of our study suggest that the presence of the malignant tumor influences the morphology of pineal cells in mice. Considering the fact that different patterns of ultrastructural changes were demonstrated in pinealocytes in different tumor types in various species, it seems that the character of the ultrastructural changes observed in tumor-bearing animals depends on the animal species and tumor type....

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Clinical Trial 2003; 24(3-4): 255-258 PubMed PMID: 14523366 Citation  Keywords:  Adult, Cross-Sectional Studies, Female, Gastric Emptying:physiology, Graves Disease:physiopathology, Half-Life, Humans, Hyperthyroidism:physiopathology, Kinetics, Male, Radionuclide Imaging, Radiopharmaceuticals, Stomach:diagnostic imaging, Technetium Tc .   

INTRODUCTION AND AIM: About 15% of hyperthyroid patients suffer from gastrointestinal symptoms such as diarrhea, constipation, nausea and early satiety the problem. Published reports on the topic of gastric emptying in hyperthyroidism are rare and discrepant in their results.

PATIENTS AND METHODS: Thirteen patients (8 women, 5 male; aged 41.92+/-1.491 SE yr) with a recently established diagnosis of subclinical hyperthyroidism due to Graves-Basedow disease and as control group 10 age-matched healthy subject (7 women, 3 male; 39.6+/-2.918 SE yrs) participated in this study. Scintigraphic method (food labeled with 99mTc sulfur colloid) was used for measurement of gastric emptying.

RESULTS: Gastric emptying time was similar in both subclinical hyperthyroid and control groups (p=0.413).

DISCUSSION: There are few studies on the subject of gastric emptying in hyperthyroidism with either delayed emptying or with emptying time similar to controls. In the only one study in subclinical hyperthyroidism, gastric emptying was found to be delayed. We also found that gastric emptying was delayed in subclinical hyperthyroidism. On the basis of this and other studies, we may suggest that in subclinical hyperthyroidism, gastric emptying of solids were similar to that in age-matched healthy control subjects and gastrointestinal dysfunction is dependent on severity of the hyperthyroid state and might be a result of impaired neuro-hormonal regulation. Yet the data must be supported on larger groups....

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