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Comparative Study 2007; 28(5): 717-720 PubMed PMID: 17984942 Citation  Keywords:  Animals, Estradiol:administration & dosage, Female, Homocysteine:blood, Hormone Replacement Therapy, Ovariectomy, Ovary:physiology, Pineal Gland:physiology, Progesterone:administration & dosage, Rats, Rats, Sprague-Dawley,.   

OBJECTIVE: Hyperhomocysteinemia plays a role in obstetric and gynecological diseases and such diseases are seen as a consequence of an impaired methionine cycle. In the present study, it was aimed to determine the effect of estradiol and progesterone on homocysteine levels in pinealectomized and ovariectomized rats.

MATERIALS AND METHODS: The study was carried out on 24 adult Spraque-Dawley female rats. Rats were divided into 4 groups as follows: Group 1: Sham ovariectomy group (Sham-Ovx), Group 2: Ovariectomized and sham pinealectomized group (Ovx-Sham-Px), Group 3: Ovariectomized and pinealectomized group (Ovx-Px), Group 4: Group which were supplemented with estradiol and progesterone after ovariectomy and pinealectomy (Ovx-Px-E+P). Serum homocysteine levels were determined after experimental period.

RESULTS: Homocysteine levels in Group 3 were higher than those in Groups 1, 2 and 4 (p<0.05). Homocysteine levels in Groups 2 and 4 were higher than those in Group 1 (p<0.05). Homocysteine levels in Groups 2 and 4 were not different.

CONCLUSION: The findings of the present study demonstrate that ovariectomy lead to increases homocysteine levels. Pinealectomy in addition to ovariectomy increases homocysteine levels. However, administration of estradiol and progesterone following pinealectomy prevents the increase in homocysteine levels in ovariectomized rats....

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Journal Article 2007; 28(5): 666-670 PubMed PMID: 17984941 Citation  Keywords:  Analysis of Variance, Animals, Dose-Response Relationship, Drug, Estradiol:physiology, Female, Melatonin:administration & dosage, Nerve Degeneration:pathology, Neural Conduction:physiology, Neuroprotective Agents:administration & dosage, Ovariectomy, Post.   

OBJECTIVES: Melatonin is a potent antioxidant agent and an anti-aging hormone. Serum melatonin level declines during the menopause. Estradiol, a neuroprotective ovarian hormone, also decreases during the menopause. The purpose of this study is to evaluate the effect of melatonin supplementary on peripheral nerve function in the ovariectomized (OVX)-aged rats.

METHODS: Randomly selected OVX-aged Wistar rats received injections of melatonin (5 or 20 mg/kg) daily either two or six weeks. Nerve conduction velocities and distal latencies were determined from the propagation of action potential recorded by using an extracellular electrophysiological technique.

RESULTS: The mean distal latencies of melatonin-treated groups were shorter than that of the control group. Thus, the nerve conduction velocity was significantly greater in both two weeks and six weeks melatonin treated groups as compared to the controls (p<0.001).

CONCLUSION: Melatonin alleviates the electrophysiological properties of the sciatic nerve in OVX-aged rats. Thus, melatonin supplementary may have a potential clinical application for the treatment of postmenopausal peripheral nerve degeneration....

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Comparative Study 2007; 28(5): 614-620 PubMed PMID: 17984940 Citation  Keywords:  Adrenal Medulla:drug effects, Adrenergic Uptake Inhibitors:pharmacology, Adrenocorticotropic Hormone:blood, Analysis of Variance, Animals, Corticosterone:blood, Epinephrine:blood, Fluoxetine:pharmacology, Hypothalamo-Hypophyseal System:drug effects, Male,.   

OBJECTIVE: To estimate the influence of long-term treatment with noradrenergic and serotonergic reuptake inhibitors on activity of pituitary-adrenocortical and sympatho-adrenomedullar systems in animals, we compared the effects of maprotiline (a selective inhibitor of noradrenaline reuptake) and fluxilan (a selective inhibitor of serotonin reuptake) on plasma noradrenaline (NA), adrenaline (A), adrenocorticotropic hormone (ACTH) and corticosterone (CORT) levels in unstressed control and rats exposed to chronic unpredictable mild stress (CUMS).

METHODS: Plasma NA and A were assayed by a radioenzymatic method. Plasma CORT was measured using RIA kits and plasma ACTH by a chemiluminescent method.

RESULTS: CUMS did not affect blood plasma NA, A and ACTH content, but elevated plasma CORT level. Maprotiline elevated plasma NA content both in unstressed control and CUMS group, whereas plasma A remained unchanged. Fluxilan acted significantly increasing plasma NA and A concentrations both in control and CUMS rats. Neither maprotiline nor fluxilan affected plasma ACTH level both in unstressed control and CUMS animals. Plasma CORT level in unstressed control rats remained unchanged after maprotiline and fluxilan treatment, while being significantly decreased in CUMS rats.

CONCLUSION: Chronic treatment of adult rat males with maprotiline, a noradrenaline reuptake inhibitor activated sympathoneural system. On the other hand, fluxilan, a serotonin reuptake inhibitor activated both sympathoneural and adrenomedullar system, whereas both antidepressants desensitized HPA axis. The findings described here suggest that elevated plasma catecholamines my contribute to adverse effects of these drugs on cardiovascular parameters during antidepressant therapy....

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Comparative Study 2007; 28(5): 575-579 PubMed PMID: 17984939 Citation  Keywords:  Adult, Aged, Circadian Rhythm:physiology, Humans, Male, Middle Aged, Nerve Growth Factors:blood, Oxygen:blood, Polysomnography, S100 Calcium Binding Protein beta Subunit, S100 Proteins:blood, Severity of Illness Index, Sleep Apnea, Obstructive:blood, Stat.   

OBJECTIVE: Responsible for sleep brain perfusion changes, obstructive sleep apnea (OSA) constitutes a cardiovascular risk. To find out about any diffuse damage to the brain tissue, we studied the S100B protein, whose serum level is known to rise in stroke and craniocerebral trauma.

METHODS: 60 men (mean age 51.7+/-11.8 years) referred to us for OSA without any major comorbidity were examined polygraphically. S100B was determined with electrochemiluminiscence immunoassay (ECLIA) from evening and morning blood samples.

RESULTS: All sixty men were diagnosed with OSA. The difference between the evening level of S100B 0.068+/-0.030 microg/l and the morning level 0.059+/-0.029 microg/l was significant (p=0.0004). Patients with mild OSA were found to have the evening S100B 0.063+/-0.023 microg/l, the morning level 0.042+/-0.012 microg/l, the difference being significant (p=0.00051). In moderate OSA the difference between the evening -0.070+/-0.017 microg/l and morning levels -0.055+/-0.025 microg/l was less significant (p=0.043). In severe OSA no difference was found between the evening and morning concentrations of S100B (0.070+/-0.036 microg/l and 0.070+/-0.031 microg/l respectively). The difference between the evening and morning S100B levels correlated negatively with AHI and ODI and positively with basal saturation and average minimal oxygen saturation.

CONCLUSIONS: Sleep with signs of severe OSA influences S100B protein release....

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Journal Article 2007; 28(5): 671-674 PubMed PMID: 17984938 Citation  Keywords:  Animals, Aromatase:metabolism, Cholestenone 5 alpha-Reductase:metabolism, Female, Hypothalamus, Middle:embryology, Immobilization, Pregnancy, Prenatal Exposure Delayed Effects, Preoptic Area:embryology, Rats, Rats, Wistar, Sex Characteristics, Stress, Psy.   

OBJECTIVES: Prenatal stress results in demasculinization and feminization of sexual behavior in adult male rats. Earlier the preventive effect of testosterone replacement of an androgen deficiency in male fetuses during exposure to stress has been demonstrated. Nevertheless the neuroendocrine mechanisms underlying hormonal protection of the brain sexual differentiation are not clear.

MATERIAL AND METHODS: Time-mated rats were undergone to 1 h strict immobilization during days 15 to 21 of gestation. Another group of stressed dams was injected with testosterone propionate on the 17th, 19th and 21st gestational days subcutaneously (5 mg/kg b.w.) 30 min prior to restraining. Aromatase and 5alpha-reductase activities were determined in the preoptic area and medial basal hypothalamus of 10-day old offspring.

RESULTS: Aromatase activity in the preoptic area declined in affected with prenatal stress males and reached the normal female level. It completely restored in prenatally stressed males under influence of prenatal testosterone replacement. 5alpha-reductase activity decreased in the preoptic area of prenatally stressed females. In those pretreated with testosterone propionate, 5alpha-reductase activity was significantly elevated above normal level.

CONCLUSIONS: The data obtained demonstrate a preservation of aromatase activity in the preoptic area of males resulted from testosterone replacement. Presumably testosterone exerts its protective effect on the male sexual behavior by prevention of neurochemical feminization of the brain preoptic area and, perhaps, due to some other mechanisms....

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Journal Article 2007; 28(5): 610-613 PubMed PMID: 17984936 Citation  Keywords:  Adjustment Disorders:blood, Adrenocorticotropic Hormone:blood, Adult, Anxiety Disorders:blood, Circadian Rhythm:physiology, Crime Victims:psychology, Dehydroepiandrosterone:blood, Depressive Disorder:blood, Female, Humans, Hydrocortisone:blood, MMPI, Male.   

OBJECTIVES: Evidence in the literature suggests stress-related changes of hypothalamus-pituitary-adrenal (HPA) axis in mobbing. We investigated the association between HPA activity and psychological profiles in mobbing, using a multidisciplinary approach.

DESIGN: Forty-eight victims of mobbing were evaluated by a working group of the Departments of Occupational Medicine, Psychiatry and Internal Medicine. After an informed consent, a detailed occupational history, a psychiatric interview with Minnesota Multiphasic Personality Inventory 2 (MMPI-2) administration and a blood sample (8:00 AM) for the determination of basal adrenocorticotropin (ACTH), cortisol and dehydroepiandrosterone sulphate (DHEAS) plasma levels were collected. Twenty-six patients received an overnight dexamethasone (dex) test.

RESULTS: Mean ACTH, cortisol and DHEAS levels were within normal ranges. The dex-test response was normal, with a significant hormone suppression (ACTH p<0.001, cortisol p<0.001, DHEAS p<0.001). The correlations between basal hormones and the psychometric scales of MMPI-2 revealed that cortisol was significantly and negatively related to Psychasthenia (Pt, p=0.003) and Depression (D, p=0.006), while DHEAS showed a significant negative correlation to Hysteria (Hy, p=0.008). Basal ACTH levels were not significantly related to psychometric scales.

CONCLUSION: A significant inverse correlation between morning plasma cortisol levels and psychometric parameters in victims of mobbing with adjustment disorders was observed. A larger group of patients is necessary to identify and validate a cut-off cortisol level that may become an innovative biological parameter for the diagnosis and follow-up in victims of mobbing....

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Journal Article 2007; 28(5): 629-632 PubMed PMID: 17984934 Citation  Keywords:  Adult, Amino Acid Substitution, China, Female, Fibrillin-1, Fibrillins, Genetic Predisposition to Disease, Humans, Latent TGF-beta Binding Proteins:metabolism, Male, Marfan Syndrome:genetics, Microfilament Proteins:genetics, Middle Aged, Mutation, Missens.   

: In order to further understand the role of fibrillin-1 (FBN1, OMIM 134797) perturbations in the pathogenesis of Marfan syndrome (MFS, OMIM 154700) we studied a Han Chinese family in which MFS was segregating. In the Chinese family with 5 affected members, mutation screening for FBN1 was performed using direct sequencing. A novel non-synonymous mutation in the transforming growth factor beta binding protein-like (TB) domain of the FBN1 gene was found. The missense mutation c.3022T>C (C1008R) located in exon 24. This mutation was present in the proband and in two other affected family members, but in neither unaffected family members nor unrelated control subjects. The novel non-synonymous mutation, c.3022T>C (C1008R) in the TB domain of FBN1 gene, may be involved in the pathogenesis of MFS in a Han Chinese family....

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Journal Article 2007; 28(5): 662-665 PubMed PMID: 17984929 Citation  Keywords:  Adolescent, Adult, Altruism, Amylases:metabolism, Decision Making:physiology, Games, Experimental, Humans, Male, Reference Values, Reward, Saliva:metabolism, Self Concept, Social Perception,.   

OBJECTIVE: Little is known regarding the relationship between social evaluation-induced neuroendocrine responses and generosity in game-theoretic situations. Previous studies demonstrated that reputation formation plays a pivotal role in prosocial behavior. This study aimed to examine the relationships between a social evaluation-induced salivary alpha-amylase (sAA) response and generosity in the dictator game. The relationship is potentially important in neuroeconomics of altruism and game theory.

METHODS: We assessed sAA and allocated money in the dictator game in male students with and without social evaluation. RESULTS Social evaluation-responders allocated significantly more money than controls; while there was no significant correlation between social evaluation-induced sAA elevation and the allocated money.

CONCLUSIONS: Social evaluation significantly increases generosity in the dictator game, and individual differences in trait characteristics such as altruism and reward sensitivity may be important determinants of generosity in the dictator game task....

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