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Journal Article 2003; 24(5): 348-349 PubMed PMID: 14647011 Citation  Keywords:  Adolescent, Amino Acids:blood, Delirium:blood, Hallucinogens:adverse effects, Humans, N-Methyl-3,4-methylenedioxyamphetamine:adverse effects, Substance-Related Disorders:blood,.   

: Recreational use of the illegal drug "ecstasy" has increased dramatically in recent years. We have measured 33 different plasma amino acids in ecstasy users and controls. Significant differences were found for phosphoserine, glutamate, citrulline, methionine, tyrosine and histidine. Resembling changes in the plasma amino acids have been described in acute transient polymorphous psychosis. Thus, alterations in plasma - methionine and phosphoserine or other amino acids could be involved in the psychical symptoms produced by MDMA....

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Journal Article 2003; 24(5): 345-347 PubMed PMID: 14647010 Citation  Keywords:  Animals, Antioxidants:pharmacology, Hyperthyroidism:drug therapy, Injections, Intraperitoneal, Male, Melatonin:pharmacology, Rats, Rats, Sprague-Dawley, Testis:drug effects, Testosterone:metabolism, Thyroid Gland:drug effects, Thyroid Hormones:metabolism,.   

OBJECTIVE: Melatonin has a general inhibitory effect on the reproductive system and thyroid functions. Testosterone secretion increases in parallel to thyroid hormones in hyperthyroidism. The aim of this study was to investigate the effects of melatonin application on total T3, T4 and testosterone in hyperthyroid rats.r />r /> METHODS: This study was performed on 4 groups each consisted of 6 male Spraque Dawley rats. Control group (G1); sham group (G2); applied 0.5 ml/day of serum physiologic intraperitoneally for 2 weeks, hyperthyroid group (G3); applied 0.3 mg/kg/day thyroxine intraperitoneally for 2 weeks, and hyperthyroid and melatonin supplemented group (G4); applied 0.3 mg/kg/day thyroxine and 3 mg/kg/day melatonin. Blood samples taken by way of decapitation were analysed for total T3, T4 and testosterone by RIA.r />r /> RESULTS: Serum total T3 and total testosterone levels were the highest in hyperthyroid group (G3), whereas in hyperthyroid and melatonin supplemented group (G4) were the lowest (P<0.001). Total T4 levels were higher in group 3 than group 1, 2 and 4 (P<0.001).r />r /> CONCLUSION: Results revealed that melatonin supplementation in hyperthyroidism suppress secretion of thyroid hormones and testosterone secretion....

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Journal Article 2003; 24(5): 341-344 PubMed PMID: 14647009 Citation  Keywords:  3-Hydroxybutyric Acid:metabolism, Animals, Antioxidants:pharmacology, In Vitro Techniques, Malates:metabolism, Male, Melatonin:pharmacology, Mitochondria, Liver:drug effects, Oxygen Consumption:drug effects, Rats, Rats, Wistar, Succinic Acid:metabolism,.   

OBJECTIVE: To examine the in vitro effect of melatonin on rat mitochondrial liver respiration.r />r /> METHODS: Oxygen consumption by liver mitochondria was measured polarographically in the presence of one of the following Krebs' cycle substrates: Lsuccinate, DL-3- beta-hydroxybutyrate or L-malate. Respiratory velocities at rest (state 4) and during rapid respiration in the presence of substrate and adenosine diphosphate (state 3) were measured in the presence of 10 (-9)-10(-3) M concentrations of melatonin.r />r /> RESULTS: In vitro melatonin (10(-7)-10(-3) M) reduced state 3 mitochondrial respiration. Basal, state 4 respiration was not affected by melatonin. Consequently, control respiratory index (i.e., the ratio of state 3 to state 4 respiration) was inhibited by melatonin with a threshold at 10(-7) M concentration.r />r /> CONCLUSION: The ability of melatonin to curtail acutely the stimulation of oxygen consumption in liver mitochondria may protect the mitochondria from excessive oxidative damage....

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Journal Article 2003; 24(5): 339-340 PubMed PMID: 14647008 Citation  Keywords:  Blood Pressure, Blood Pressure Monitoring, Ambulatory:standards, Circadian Rhythm, Heart Rate, Humans, Hypertension:diagnosis, Seasons,.   

: The diagnoses of summer or winter hypertension in one and the same person can depend upon the clock hour of measurement....

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Clinical Trial 2003; 24(5): 334-338 PubMed PMID: 14647007 Citation  Keywords:  Adenoma:drug therapy, Adult, Antineoplastic Agents:administration & dosage, Apoptosis:drug effects, Female, Humans, Male, Middle Aged, Peptides, Cyclic:administration & dosage, Pituitary Neoplasms:drug therapy, Somatostatin:administration & dosage,.   

OBJECTIVES: Apoptosis of endocrine cells represents one of factors significantly affected the control of hormones secretion. Present study aimed to examine whether treatment of somatotropinoma types tumours with somatostatine analogue (lanreotide) results in apoptosis.r />r /> MATERIAL AND METHODS: The studies were performed on 35 patients with somatotropinoma type tumours on whom adenomectomy was performed by transsphenoidal approach. The operative material was examined by cellular morphology, based on light and electron microscopy and chromosomal ladder formation assay.r />r /> RESULTS: The number of apoptotic cells showed features typical for the process as condensation and fragmentation of chromatin, vacuolisation, damage of the inner structure of mitochondria and oligonucleosomal fragmentation of DNA was found in the study material. The results of the studies demonstrated the occurrence of lanreotide induced apoptosis in somatotropinoma type tumours. The grade of apoptotic cells in macroadenomas type adenomas, treated with lanreotide, ranged from 4.0% to 17.1% (mean 8.7+/-2.6%). Patients in whom hypophysectomy was not preceded by lanreotide treatment demonstrated low level of apoptotic cells (no more than 3.5%).r />r /> CONCLUSIONS: The studies showed that treatment with somatostatine analogue-lanreotide induced apoptosis of tumour cell suggesting that the induction of apoptotic cell death may be involved in the anticancer activity of somatostatine analogue....

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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.r />r /> 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.r />r /> 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): 325-328 PubMed PMID: 14647005 Citation  Keywords:  Aldosterone:urine, Blood Pressure:genetics, Genetic Markers, Humans, Hypertension, Renal:genetics, Insulin:genetics, Middle Aged, Minisatellite Repeats, Phenotype, Pilot Projects, Polymorphism, Restriction Fragment Length, Potassium:urine, Quantitative Tr.   

BACKGROUND: Blood pressure regulation is a complex process influenced by numerous environmental and genetic factors. Consequently, there's no cookie-cutter approach for the elucidation of of the genetic mechanism involved. One of the goals of molecular geneticists in the field of hypertension is to unravel the genetic architecture of blood pressure regulation.r />r /> METHODS: With the aim of identifying quantitative trait loci participating in the control of blood pressure, we carried out a pilot study on a sample population of middle-aged, U.S. Caucasians (44 subjects). The design of the study was to search for associations between clinical variables of blood pressure regulation pertaining to the renin-angiotensin-aldosterone system (systolic and diastolic blood pressures, urinary excretion of sodium, potassium and aldosterone, plasma renin activity) and a genetic marker at a candidate gene locus - the human insulin gene (INS) RESULTS: We observed significant associations between a variable number of tandem repeats (VNTR) marker (visualized as a biallelic, class I/class III marker system) localized at the 5' end of the human INS gene, and plasma renin activity and urinary sodium, potassium and aldosterone.r />r /> CONCLUSION: Our results indicate that between 6 and 10 QTLs with comparable effects could be involved in blood pressure regulation via the rennin angiotensin system....

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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.r />r /> 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.r />r /> 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.r />r /> 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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