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Gunbey H.P.,Ondokuz Mayis University | Gunbey E.,Ondokuz Mayis University | Aslan K.,Ondokuz Mayis University | Bulut T.,Adyaman University | And 2 more authors.
Clinical Neuroradiology | Year: 2015

Objective: Tinnitus is defined as an imaginary subjective perception in the absence of an external sound. Convergent evidence proposes that tinnitus perception includes auditory, attentional and emotional components. The aim of this study was to investigate the thalamic, auditory and limbic interactions associated with tinnitus-related distress by Diffusion Tensor Imaging (DTI). Methods: A total of 36 tinnitus patients, 20 healthy controls underwent an audiological examination, as well as a magnetic resonance imaging protocol including structural and DTI sequences. All participants completed the Tinnitus Handicap Inventory (THI) and Visual Analog Scales (VAS) related with tinnitus. The fractional anisotropy (FA) and apparent diffusion coefficient (ADC) values were obtained for the auditory cortex (AC), inferior colliculus (IC), lateral lemniscus (LL), medial geniculate body (MGB), thalamic reticular nucleus (TRN), amygdala (AMG), hippocampus (HIP), parahippocampus (PHIP) and prefrontal cortex (PFC). Results: In tinnitus patients the FA values of IC, MGB, TRN, AMG, HIP decreased and the ADC values of IC, MGB, TRN, AMG, PHIP increased significantly. The contralateral IC-LL and bilateral MGB FA values correlated negatively with hearing loss. A negative relation was found between the AMG-HIP FA values and THI and VAS scores. Bilateral ADC values of PHIP and PFC significantly correlated with the attention deficiency—VAS scores. Conclusion: In conclusion, this is the first DTI study to investigate the grey matter structures related to tinnitus perception and the significant correlation of FA and ADC with clinical parameters suggests that DTI can provide helpful information for tinnitus. Magnifying the microstructures in DTI can help evaluate the three faces of tinnitus nature: hearing, emotion and attention. © 2015 Springer-Verlag Berlin Heidelberg Source


Gunbey H.P.,Ondokuz Mayis University | Gunbey E.,Ondokuz Mayis University | Sayit A.T.,Ondokuz Mayis University | Aslan K.,Ondokuz Mayis University | And 2 more authors.
Surgical and Radiologic Anatomy | Year: 2016

Purpose: We hypothesized that the cochlear–carotid interval (CCI), which is defined as the smallest distance along the petrous segment of the internal carotid artery and basal turn of cochlea, may be associated with direct stimulation of hair cells, thereby affecting tinnitus perception. The aim of this study was to investigate the relationships between the CCI, tinnitus perception, and accompanying hearing loss in patients with tinnitus. Methods: The CCI on both sides was measured independently by two observers from the temporal 3D b-FFE MR images of 25 patients with tinnitus and 20 age/gender matched control subjects. The relationships between CCI, tinnitus visual analog scale (VAS), and tinnitus handicap inventory (THI) were investigated. Results: CCI ranged 0.2–5.6 mm (1.9 ± 1.5) on the right and 0.1–5.4 mm (2.2 ± 1.6) on the left side in the patient group and 0.5–5.4 (1.9 ± 1.4) mm on the right and 0.3–6.7 (2.3 ± 1.7) on the left side in the control group. The differences between the two groups were not statistically significant (p > 0.05). CCI showed a strong negative correlation with THI and VAS scores on both sides. Correlation of audiologic findings with CCI revealed a significant negative correlation with pure tone average of the ipsilateral ear most affectedly at high frequencies. Conclusion: The strong negative correlation of CCI with tinnitus-related distress and accompanying sensorineural hearing loss predominantly at high frequencies suggests that further studies on patients with tinnitus that focus on this small area may help to improve the knowledge of tinnitus pathophysiology. © 2015, Springer-Verlag France. Source


Kilic V.,Medical School OMU | Kilic S.S.,Samsun Research and Training Hospital
Journal of Animal and Veterinary Advances | Year: 2012

Ghrelin is a growth-hormone releasing lipopeptide that was shown to regulate of lipid and carbohydrate metabolism and appetite. Brucellosis characterized by fever, headache, night sweats, extreme tiredness, chills and weight loss and anorexia. This research aimed to investigate the changes of ghrelin concentrations in blood of brucellosis patients 19 brucellosis patients and 16 healthy subjects with similar ages were randomly selected as control group. Serum levels of acylated ghrelin were evaluated on blood samples of the participants by Radio-Immunoassay Methods. The results showed acylated ghrelin was significantly changed in patients with brucellosis (8.9±2 pg inL-1) compared with controls (39±15.5 pg inL-1). There is no data showing ghrelin in Brucellosis in literature so far. The first evaluated results showed that appetite decrease in Brucellosis might be due to circulating level of ghrelin decrement. © 2012 Medwell Journals. Source


Beyazyildiz E.,Samsun Research and Training Hospital | Beyazyildiz O.,Samsun Research and Training Hospital | Hekimolu E.R.,Hacettepe University | Acar U.,Hacettepe University | And 5 more authors.
Stem Cells International | Year: 2014

Purpose. The current study was set out to address the therapeutic efficacy of topically applied mesenchymal stem cells (MSCs) on dry eye syndrome (DES) induced by benzalkonium chloride (BAC) in rats. Methods. Rats were divided into two groups just after establishment of DES. Eye drops containing either bromodeoxyuridine labeled MSCs (n=9) or phosphate buffer solution (n=7) were topically applied once daily for one week. Schirmer test, break-up time score, ocular surface evaluation tests, and corneal inflammatory index scoring tests were applied to all rats at baseline and after treatment. All rats were sacrificed after one week for histological and electron microscopic analysis. Results. Mean aqueous tear volume and tear film stability were significantly increased in rats treated with MSCs (P<0.05). Infiltration of bromodeoxyuridine labeled MSCs into the meibomian glands and conjunctival epithelium was observed in MSCs treated rats. Increased number of secretory granules and number of goblet cells were observed in MSCs treated rats. Conclusion. Topical application of MSCs could be a safe and effective method for the treatment of DES and could potentially be used for further clinical research studies. © 2014 Emrullah Beyazyildiz et al. Source


Beyazyildiz O.,Samsun Research and Training Hospital | Tirhis M.H.,Ulucanlar Eye Research and Training Hospital | Hekimoglu E.R.,Hacettepe University | Beyazyildiz E.,Samsun Research and Training Hospital | And 3 more authors.
Current Eye Research | Year: 2016

Purpose: To investigate histopathological changes of internal limiting membrane (ILM) in patients with epiretinal membrane (ERM)Materials and Methods: Forty-two eyes of 42 patients who were diagnosed as ERM and enrolled for vitreoretinal surgery were included in this study. Brilliant Blue G (BBG) was used to stain the ILM in all patients. ILM was peeled in all subjects and analyzed by light microscopy (methylene blue-Azur II x 40). ILM samples were then fixed in 2.5% glutaraldehyde solution and examined in JEOL-JEM 1400 and 2100F electron microscope and photographed by CCD camera (Gatan Inc., Pleasanton, CA). Results: Remained ERM fragments were observed on 80% of ILM's. Vacuolization of ILM was observed in a patient with diabetic ERM. There were cells and cellular fragments observed mostly at retinal side of ILM which was likely to be a fragment of Muller cells of retina. Conclusions: Most of the ILM's had residual ERM tissue and contained cells and cellular fragments at retinal side of ILM's. ILM peeling might have a role in decreasing ERM recurrence by removal of residual ERM tissues. © 2016 Taylor & Francis Group, LLC. Source

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