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Journal Article 2003; 24(6): 454-458 PubMed PMID: 15073575 Citation  Keywords:  Adult, Aged, Albumins:metabolism, Blood-Aqueous Barrier:drug effects, Emulsions:pharmacology, Female, Humans, Magnetic Resonance Spectroscopy, Male, Middle Aged, Nephelometry and Turbidimetry, Protons, Silicone Oils:pharmacology,.   

PURPOSE: To evaluate the function of the blood aqueous barrier(BAB) in the eyes with silicone oil emulsification (SOE).r />r /> METHODS: Protein concentrations, expressed in albumin equivalents,were determined in aqueous humor of the eyes with SOE in 11 consecutive patients by means of proton nuclear magnetic resonance (1H NMR) spectroscopy. Correlations with various clinical factors were studied.r />r /> RESULTS: Normal function of the BAB (albumin equivalents 1mg/ml and less was found in 8 eyes (73%) independently on underlying disease, early postoperative reaction after pars plana vitrectomy with SO implantation, degree of SOE and late postoperative complications. Increased permeability of the BAB (albumin equivalents equal 2, 3 and 6.5 mg/ml) was found in 3 eyes (27%) with recent acute complication (retinal detachment after SO removal in 2 eyes, and secondary angle closure glaucoma in 1 eye).r />r /> CONCLUSION: SOE in vivo was associated with increased permeability of the BAB in the minority of the eyes. Other factors should be studied to explain the variability of SOE. 1H NMR spectroscopy might be a valuable method for the study of SOE....

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Journal Article 2003; 24(6): 449-453 PubMed PMID: 15073574 Citation  Keywords:  Adolescent, Adult, Educational Measurement, Exploratory Behavior, Female, Humans, Hydrocortisone:metabolism, Male, Psychometrics, Saliva:metabolism, Stress, Psychological:diagnosis, Students:psychology,.   

OBJECTIVES: Although it is widely accepted that academic examinations are accompanied by a cortisol increase, some recent studies reported either no effect or even a decline of the cortisol level. To reevaluate these discrepancies, we investigated whether personality traits predict the cortisol response upon academic examinations.r />r /> SETTING AND DESIGN: Nineteen male and female adolescent pupils (17 to 19 years) participated in the study. Two anticipated, mandatory, routine written examinations were used as familiar stressful conditions, whereas an anticipated, mandatory oral examination in front of a board of known and unknown examiners was used as a novel stressful situation.r />r /> METHODS: Baseline, pre- and postexamination salivary cortisol were quantified and correlated with psychometric measures, including self-estimated stress level, obtained from a five-point scale, and sensation seeking subscales according to Zuckerman.r />r /> RESULTS: Salivary cortisol response, taken as an average of all subjects, showed a transient increase upon examinations. However, comparing individual cortisol responses revealed three distinct cortisol profiles, including a transient increase (Type 1), a transient decline (Type 2), or no response (Type 3). Type 1 predominates in examinations combined with novelty. A moderate negative association was noted between saliva cortisol concentrations on some sensation seeking subscales. Self-reported stress levels did not significantly correlate with salivary cortisol concentration.r />r /> CONCLUSION: Our findings show that upon academic examinations the cortisol response varies among subjects. A moderate negative association was unveiled by correlating individual cortisol responses with sensation seeking subscales....

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Journal Article 2003; 24(6): 445-448 PubMed PMID: 15073573 Citation  Keywords:  Adult, Female, Homocysteine:blood, Humans, Lipid Peroxidation, Lipid Peroxides:metabolism, Malondialdehyde:blood, Pre-Eclampsia:blood, Pregnancy, Severity of Illness Index,.   

OBJECTIVE: To investigate the possible correlation between plasma malondialdehyde and homocysteine levels of preeclamptic patients.r />r /> DESIGN: Venous blood samples of 20 preeclamptics and 20 healthy pregnant controls were collected. Plasma malondialdehyde and homocysteine concentrations were measured and the correlation between them was investigated. Mann Whitney U test and Spearman correlation analysis were used for statistical analysis.r />r /> SETTING: University of Firat, Medical School.r />r /> RESULTS: Plasma malondialdehyde and homocysteine concentrations were higher in preeclamptic patients (p<0.05) and a positive correlation between these parameters was found (r: 0.77, p<0.01, n:20).r />r /> CONCLUSION: Our results may put forward some new strategies in the research of etiopathogenesis and treatment of preeclampsia....

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Journal Article 2003; 24(6): 440-444 PubMed PMID: 15073572 Citation  Keywords:  Adjuvants, Immunologic:pharmacology, Breast Neoplasms, Cell Division:drug effects, Cell Line, Tumor:cytology, Drug Interactions, Estradiol:pharmacology, Estrogen Receptor alpha, Estrogen Receptor beta, Female, Gene Expression Regulation, Neoplastic:drug e.   

OBJECTIVES: Detection of the antiestrogenic effect of melatonin on various breast cancer cell lines and its dependence of the differential expression of estrogen receptors (ERalpha and ERbeta) and melatonin receptors (mt1 and RZRalpha).r />r /> SETTING AND DESIGN: Dose-response curves of estradiol were determined in 6 different breast cancer cell lines using a colorimetric proliferation assay in the absence or presence of various melatonin concentrations.r />r /> METHODS: In order to detect the minor growth inhibitory effect of melatonin, a simple yet novel approach was employed: instead of incubating cells at single estradiol-concentrations at increasing melatonin levels, breast cancer cells were grown in microwell-plates for 4 days at increasing concentrations of estradiol (10(-12)M - 10(-10)M) in the absence or presence of melatonin (10(-9)M - 10(-8)M). Cell number was determined using Alamar blue and colorimetry. RT-PCR was performed for the expression of ERalpha, ERbeta, RZRalpha and mt1.r />r /> RESULTS: Melatonin at concentrations of 10(-9)M and 5 x 10(-9)M shifted the dose-response curves of estradiol to higher concentrations. Responsiveness to melatonin depended on expression of ERalpha but not on ERbeta. mRNA of ERbeta was not detectable in the breast cancer cell lines used. Only small amounts of mt1 transcripts were detectable in MCF-7 cells of one source. In MCF-7 cells transfected with the mt1 gene and in an ovarian cancer cell line mt1 was expressed at significant levels. RZRalpha was expressed in all tested cell lines at different amounts.r />r /> CONCLUSION: The growth of all ERalpha-positive breast cancer cell lines can be inhibited by melatonin. The effect in most cell lines is weak yet clearly reproducible. RZRalpha clearly contributes to the growth inhibitory effect of melatonin....

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Journal Article 2003; 24(6): 435-439 PubMed PMID: 15073571 Citation  Keywords:  2-Amino-5-phosphonovalerate:pharmacology, Age Factors, Animals, Dizocilpine Maleate:pharmacology, Excitatory Amino Acid Antagonists:pharmacology, Hypothalamus:drug effects, Injections, Intraventricular, Male, Prolactin:metabolism, Rats, Rats, Wistar, Rece.   

OBJECTIVE: To investigate the effects of N-methyl-D-aspartate (NMDA) receptor antagonists on restraint-induced release of prolactin (PRL) in male Wistar rats of different ages.r />r /> DESIGN: Rats were implanted with a brain ventricular for icv injection, and with a jugular vein cannula for iv injection. Competitive NMDA receptor antagonist AP-5 and noncompetitive NMDA receptor blocker MK-801 was injected via brain cannula or vein cannula and was restrained for 3 hours. The blood sample was collected through vein cannula during the restraint. The plasma concentration of prolactin was measured by RIA.r />r /> RESULTS: The restraint-induced PRL release in the adult rat (12-weeks) was significantly suppressed by MK-801 (50 microg/rat, icv; or 5 mg/kg, iv) and was partially inhibited by pretreatment of AP-5 (50, 100 microg/rat, icv), but was not changed by systemic administration of AP-5 (10 mg/kg, iv). MK-801 (5 mg/kg, iv) prevented the restraint-induced PRL release in the peripuberal rat (45-days) and in the middle-aged rat (16-months).r />r /> CONCLUSION: Central NMDA receptors mediate restraint-induced PRL release in the male rat....

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Journal Article 2003; 24(6): 431-434 PubMed PMID: 15073570 Citation  Keywords:  Adult, Anorexia Nervosa:metabolism, Appetite:physiology, Diabetes Mellitus:metabolism, Feedback, Physiological, Female, Glucose Tolerance Test, Human Growth Hormone:metabolism, Humans, Hypertension:metabolism, Leptin:blood, Luteinizing Hormone:metabolism,.   

OBJECTIVE: It has been reported that neuropeptides may play a role in the control of appetite and in the mechanism of hormone release. Neuropeptides such as beta-endorphin, neuropeptide Y (NPY), galanin and leptin may affect hormones release, on the other hand the hormonal status may modulate neuropeptide activity.r />r /> METHODS: The material consisted of 90 obese women, 30 women with Anorexia Nervosa, and 30 healthy, lean women of control group. Plasma beta-endorphin, NPY, leptin, somatostatin and serum pituitary and gonadal hormones concentrations were measured with RIA methods.r />r /> RESULTS: We observed the highest plasma NPY levels in obese hypertensive and diabetic patients. After carbohydrate administration (OGTT) a marked increase of insulin, beta-endorphin and NPY was found. The blunted response of GH to GH-RH may be connected with increased somatostatin activity and hyperinsulinemia. The abnormal response of LH to opioid blockade may be a result of disturbed opioid and NPY activities in obese patients. However in patients with anorexia nervosa, plasma leptin and NPY concentrations were low. The disturbances in beta-endorphin release are also observed.r />r /> CONCLUSIONS: The neuroendocrine disturbances in obesity and in anorexia nervosa are opposite. The feedback mechanism between leptin and NPY is disturbed in both in obesity and in anorexia nervosa. An abnormal activity of neuropeptides may lead to disturbed control of appetite and hormonal dysregulation in eating disorders....

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Comparative Study 2003; 24(6): 425-430 PubMed PMID: 15073569 Citation  Keywords:  Adenoma:pathology, Adenoma, Oxyphilic:pathology, Adolescent, Adult, Aged, Female, Follow-Up Studies, Humans, Male, Middle Aged, Neoplasm Recurrence, Local, Pituitary Neoplasms:pathology, Prognosis, Retrospective Studies, Sex Characteristics, Treatment Out.   

OBJECTIVES: Clinically non-functioning pituitary adenomas are common tumors of the pituitary gland. No studies have yet documented gender-related differences in the growth and presentation of these tumors and nothing is known about their effects on their subsequent surgical outcome and prognosis.r />r /> SETTING AND DESIGN: Twenty-eight patients with non-functioning pituitary adenoma, that met strict inclusion criteria, and that underwent surgical treatment between January 1990 and June 1997, were retrospectively reviewed.r />r /> METHODS: The patient charts, as well as histological (incl. immunohistochemistry) and electron microscopic findings were analyzed. Tumor invasiveness was classified according to the modified Hardy criteria.r />r /> MAIN FINDINGS: Eleven patients were women and seventeen were men; the female-to-male-ratio was 1:1.5. Men were significantly older, both at diagnosis and surgery. Visual field defect and visual acuity deficit were the most common presenting symptoms with similar occurrence both in women and men, whereas blindness predominated in women. Microadenomas and invasive adenomas did not differ significantly in MIB-1 index, but patients less than 35 years old had higher MIB-1 indices (n=4, 1.72+/-1.15), than did patients over 45 years (n=11, 0.63+/-0.42) (p: n.s.). MIB-1 labeling indices were higher in adenomas of female compared to male patients (1.5 +/-1.2 vs. 0.8+/-1.8; p < 0.003). The overall outcome was significantly worse in women than in men.r />r /> CONCLUSION: The biology and the clinical course of clinically non-functioning pituitary adenoma seem to differ in women and men. In men, tumors are smaller and less invasive at surgery, and the outcome is better than in women. The present findings may justify a more aggressive therapeutic approach to clinically non-functioning pituitary adenomas in women than in men, especially to improve the availability of viable pituitary cells at the time of surgery....

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Journal Article 2003; 24(6): 420-424 PubMed PMID: 15073568 Citation  Keywords:  Adult, Analysis of Variance, Cells, Cultured, Corticotropin-Releasing Hormone:immunology, Female, Humans, Interferon-gamma:metabolism, Interleukin-10:metabolism, Leukocytes:cytology, Male, Neuroimmunomodulation:drug effects, Serotonin:immunology, Tumor Ne.   

: Both corticotropin releasing hormone (CRH) and serotonin (5-HT) participate in the stress response and are known to modulate cytokine release by human immune cells. Extracellular 5-HT concentrations at or above the serum values have negative immunoregulatory effects by inhibiting the production of interferon-gamma (IFNgamma), a pro-inflammatory cytokine produced by Th-1-like lymphocytes, whereas 5-HT has no significant effects on the production of interleukin-10 (IL-10), an anti-inflammatory cytokine. In one study, CRH significantly decreases IFNgamma production by cultured human peripheral blood immunocytes, whereas in other studies CRH increases the production of cytokines, such as IL-1, IL-2 and IL-6. The aims of the present study were to examine i) the effects of CRH, 10-9 M, 10(-8) M and 10(-7) M, on the stimulated production of IFNgamma, IL-10 and tumor necrosis factor-alpha (TNFalpha) by human whole blood; and ii) whether CRH, 10(-9) M, 10(-8) M and 10(-7) M, may antagonize some of the negative immunoregulatory effects of 5-HT, 1.5 microg/mL or 15 microg/mL. We found that CRH, 10(-9) M, 10(-8) M and 10(-7) M, had no significant effects either on the stimulated production of IFNgamma, IL-10 or TNFalpha or on the IFNg/IL-10 production ratio, which reflects the pro-inflammatory capacity of the culture. 5-HT, 1,5 microg/dL and 15 microg/dL, significantly suppressed the production of IFNgamma and TNFalpha and the IFNg/IL-10 production ratio. CRH, 10(-7) M, significantly reversed the 5-HT (1.5 microg/mL and 15 microg/mL)-induced suppression of IFNg production. CRH at all concentrations significantly blocked the 5-HT (1.5 microg/mL and 15 microg/mL)-induced suppression of TNFalpha production. The results suggest that CRH has no significant direct effects on the production of IFNgamma, IL-10 and TNFalpha, but antagonizes the negative immunoregulatory effects of 5-HT on the production of IFNgamma and TNFalpha and on the IFNgamma/IL-10 production ratio....

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