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Ankara, Turkey

Williams A.L.,Thomas Jefferson University | Gatla S.,Thomas Jefferson University | Leiby B.E.,Thomas Jefferson University | Fahmy I.,Egyptian Research Institute of Ophthalmology | And 14 more authors.
Journal of Glaucoma | Year: 2013

PURPOSE:: To investigate the amount of intraocular pressure (IOP) asymmetry in a large group of ethnically diverse patients with and without glaucoma, and to delineate the risk for glaucoma which increasing amounts of IOP asymmetry confer upon the patient. PATIENTS AND METHODS:: Collaborative retrospective study of 326 glaucoma patients and 326 controls. Former Wills Eye Institute fellows collected single pre-treatment measurements of IOP on patients diagnosed as having definite glaucoma based on characteristic optic nerve damage and confirmatory visual field damage. Patients with a normal eye examination who had normal-appearing optic discs and no apparent glaucoma, or who had a normal eye examination in association with refractive error or cataract, were used as controls. RESULTS:: Intraocular pressure asymmetry is a significant risk factor for having glaucoma (odds ratio, 2.14; 95% confidence interval, 1.86-2.47; P<0.001). Absence of IOP asymmetry between the fellow eyes is associated with a 1% probability of having glaucoma. A difference of 3 mm Hg is associated with a 6% probability of having glaucoma, and a difference of >6 mm Hg with a 57% probability of having glaucoma. The association between IOP asymmetry and glaucoma status is significant for subjects with both elevated IOP (P=0.014) and statistically normal IOP (maximum IOP≤21 mm Hg; P<0.001). CONCLUSIONS:: Inter-eye asymmetry of IOP is a common finding in patients with glaucoma. There is a direct relationship between the amount of IOP asymmetry between the fellow eyes and the likelihood of having glaucoma. Copyright © 2013 by Lippincott Williams & Wilkins. Source

Tan D.-X.,University of Texas Health Science Center at San Antonio | Korkmaz A.,Gulhane Medical School | Reiter R.J.,University of Texas Health Science Center at San Antonio | Manchester L.C.,University of Texas Health Science Center at San Antonio
Journal of Pineal Research | Year: 2014

The purpose of this report is to emphasize the potential utility for the use of melatonin in the treatment of individuals who are infected with the Ebola virus. The pathological changes associated with an Ebola infection include, most notably, endothelial disruption, disseminated intravascular coagulation and multiple organ hemorrhage. Melatonin has been shown to target these alterations. Numerous similarities between Ebola virus infection and septic shock have been recognized for more than a decade. Moreover, melatonin has been successfully employed for the treatment of sepsis in many experimental and clinical studies. Based on these factors, as the number of treatments currently available is limited and the useable products are not abundant, the use of melatonin for the treatment of Ebola virus infection is encouraged. Additionally, melatonin has a high safety profile, is readily available and can be orally self-administered; thus, the use of melatonin is compatible with the large scale of this serious outbreak. © 2014 John Wiley & Sons A/S.. Source

Reiter R.J.,University of Texas Health Science Center at San Antonio | Tan D.X.,University of Texas Health Science Center at San Antonio | Korkmaz A.,Gulhane Medical School | Rosales-Corral S.A.,Research Center Biomedica Of Occidente Del Instituto Mexicano Del Seguno Social
Human Reproduction Update | Year: 2014

background: Research within the last decade has shown melatonin to have previously-unsuspected beneficial actions on the peripheral reproductive organs. Likewise, numerous investigations have documented that stable circadian rhythms are also helpful in maintaining reproductive health. The relationship of melatonin and circadian rhythmicity to maternal and fetal health is summarized in this review. methods: Databases were searched for the related published English literature up to 15 May 2013. The search terms used in various combinations included melatonin, circadian rhythms, biological clock, suprachiasmatic nucleus, ovary, pregnancy, uterus, placenta, fetus, pre-eclampsia, intrauterine growth restriction, ischemia-reperfusion, chronodisruption, antioxidants, oxidative stress and free radicals. The results of the studies uncovered are summarized herein. results: Both melatonin and circadian rhythms impact reproduction, especially during pregnancy. Melatonin is a multifaceted molecule with direct free radical scavenging and indirect antioxidant activities. Melatonin is produced in both the ovary and in the placenta where it protects against molecular mutilation and cellular dysfunction arising from oxidative/nitrosative stress. The placenta, in particular, is often a site of excessive free radical generation due to less than optimal adhesion to the uterine wall, which leads to either persistent hypoxia or intermittent hypoxia and reoxygenation, processes that cause massive free radical generation and organ dysfunction. This may contribute to pre-eclampsia and other disorders which often complicate pregnancy. Melatonin has ameliorated free radical damage to the placenta and to the fetus in experiments using non-human mammals. Likewise, the maintenance of a regular maternal light/dark and sleep/wake cycle is important to stabilize circadian rhythms generated by the maternal central circadian pacemaker, the suprachiasmatic nuclei. Optimal circadian rhythmicity in the mother is important since her circadian clock, either directly or indirectly via the melatonin rhythm, programs the developing master oscillator of the fetus. Experimental studies have shown that disturbed maternal circadian rhythms, referred to as chronodisruption, and perturbed melatonin cycles have negative consequences for the maturing fetal oscillators, which may lead to psychological and behavioral problems in the newborn. To optimize regular circadian rhythms and prevent disturbances of the melatonin cycle during pregnancy, shift work and bright light exposure at night should be avoided, especially during the last trimester of pregnancy. Finally, melatonin synergizes with oxytocin to promote delivery of the fetus. Since blood melatonin levels are normally highest during the dark period, the propensity of childbirth to occur at night may relate to the high levels of melatonin at this time which work in concert with oxytocin to enhance the strength of uterine contractions. conclusions: Anumber of conclusions naturally evolve fromthe data summarized in this review: (i) melatonin, of both pineal and placental origin, has essential functions in fetal maturation and placenta/uterine homeostasis; (ii) circadian clock genes, which are components of all cells including those in the peripheral reproductive organs, have important roles in reproductive and organismal (fetal and maternal) physiology; (iii) due to the potent antioxidant actions of melatonin, coupled with its virtual absence of toxicity, this indoleamine mayhave utility in the treatment of preeclampsia, intrauterine growth restriction, placental and fetal ischemia/reperfusion, etc. (iv) the propensity for parturition to occur at night may relate to the synergism between the nocturnal increase in melatonin and oxytocin. © The Author 2013. Source

Yilmaz I.,Bozyaka Training and Research Hospital | Yonguc N.G.,Izmir University | Tosun S.,Ali Osman Sonmez Oncology Hospital | Kayir H.,Gulhane Medical School | Uzbay T.,Istanbul University
Journal of Neurological Sciences | Year: 2014

Objective: Audiogenic seizure (AS) susceptibility is observed following withdrawal from chronic ethanol treatment in rodents. This is the first study to investigate and compare the effects of ethanol withdrawal on the hippocampal formation in AS appeared and nonappeared animals.Material and Methods: Adult male Wistar rats (225-320 g) were used. Ethanol was given to rats in a modified liquid diet for twenty days. Daily ethanol consumption was in a range of 10.35±1.25 to 15.20±0.79 g/kg during the exposure to ethanol (7.2%). At the end of exposure to a 7.2% ethanol-containing liquid diet, ethanol was withdrawn and withdrawal signs were recorded or rated. Increased stereotyped behavior, wet dog shakes, agitation, tail-stiffness and abnormal posture and gait appeared during ethanol withdrawal in dependent rats. AS was also induced in 5 of 11 of ethanol dependent rats. Following audiogenic stimuli, rats were decapitated and their brains were removed. Neuron counts from pyramidal cell layers in CA1 and CA2-3 regions of the hippocampus were obtained from control rats and ethanoldependent rats with and without audiogenic seizure.Results: Significant neuronal losses were found in CA1 and CA2-3 regions of the hippocampal formation in the ethanol-dependent group. Neuronal loses in AS appeared group were significantly more than in AS non-appeared group.Conclusions: ASs during ethanol withdrawal significantly potentiated neuronal degeneration in all subdivisions of the CA area of the hippocampal formation in rats. Thus, prevention of seizures in alcoholic individuals may be important for protection from excessive neuronal damage in the hippocampus. © 2014, Ege University Press. All rights reserved. Source

Amasyali B.,Dumlupinar University | Kilic A.,Gulhane Medical School | Kabul H.K.,Gulhane Medical School | Imren E.,TDV 29 May Private Hospital | Acikel C.,Gulhane Medical School
Journal of Cardiology | Year: 2014

Background and purpose: Drug responses vary markedly from patient to patient in atrioventricular nodal reentrant tachycardia (AVNRT), the most common form of paroxysmal regular supraventricular tachycardia in adults. However, clinical and electrophysiological (EP) characteristics of patients with AVNRT whose tachycardia attacks could not be adequately controlled by antiarrhythmic agents have not been studied in a large patient cohort. We aimed to define the clinical and EP features of patients with drug-refractory AVNRT. Methods and results: A total of 266 consecutive patients with AVNRT undergoing catheter ablation after a period of medical treatment were analyzed: 144 patients with drug-refractory AVNRT (Group 1) and 122 patients with drug-responsive AVNRT (Group 2). Age was significantly higher (p= 0.027) and the presence of hypertension (p= 0.030), diabetes mellitus (p= 0.047), and valvular heart diseases (p= 0.008) was more frequent in Group 1 compared to Group 2. Among the EP features, atrial-His jump (81% vs 69%, p= 0.028) and atrial vulnerability (26% vs 14%, p= 0.018) were significantly higher, echo zone was significantly more long-lasting (44. ±. 24. ms vs 38. ±. 22. ms, p= 0.018), and tachycardia cycle length (TCL) was significantly longer (348. ±. 41. ms vs 329. ±. 38. ms, p= 0.000) in Group 1 than in Group 2. Multivariate analysis showed that hypertension (p= 0.036), valvular heart disease (p= 0.014), atrial vulnerability (p= 0.037), TCL (p= 0.003), and wide echo zone (p= 0.028) were independent predictors for drug-refractory AVNRT. Conclusion: In the presence of hypertension, valvular heart disease, atrial vulnerability, long-lasting echo zone, and relatively slow AVNRT, medical treatment is less likely to prevent the tachycardia episodes. © 2014 Japanese College of Cardiology. Source

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