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Dive into the research topics where Fehmi Döner is active.

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Featured researches published by Fehmi Döner.


Otolaryngology-Head and Neck Surgery | 2001

Free Radical Damage in Nasal Polyp Tissue

Harun Doğru; Namik Delibas; Fehmi Döner; Mustafa Tüz; Kemal Uygur

OBJECTIVE: To investigate whether the free radical injury in nasal polyp tissue exists or not. STUDY DESIGN: A prospective study in patients with nasal polyps. METHODS: Polyp specimens were obtained from 19 patients. Control specimens were acquired from 16 patients who underwent partial turbinectomy with concha bullosa free of rhinitis, sinusitis, and allergy, confirmed by endoscopic nasal examination, coronal paranasal sinus CT scan, and prick test. MDA levels of nasal polyps and control specimens were measured by using the method of Knudsen et al. RESULTS: The mean MDA levels of nasal polyps and control specimens were 38.2 ± 5.1 (33.3–52.2) and 33.9 ± 1.6 (32.6–37.4), respectively. MDA levels in NP were significantly higher compared with control specimens (P < 0.01). CONCLUSION: High level of MDA in nasal polyp tissue that represents FR increase supports the existence of cell injury in nasal polyp tissue. FRs should be considered in the development and life cycles of NP which is thought to have multifactorial pathogenesis.


American Journal of Otolaryngology | 1999

Pneumatized inferior turbinate

Harun Doğru; Fehmi Döner; Kemal Uygur; Orhan Gedikli; Meltem Çetin

The inferior turbinate is a separate bone that extends from the body of the maxilla to the ethmoidal crest. Its arched central portion overhangs the so-called inferior meatus, which contains the opening of the nasolacrimal duct. The inferior turbinate is part of the nasal valve area, which is the narrowest part of the nose. During inspiration, airflow is directed upward and backward, mainly over the anterior part of the inferior turbinate.l Concha bullosa, pneumatization of the middle turbinate, is a well-recognized entity. It is the most common anatomic variation of the middle turbinate leading to various clinical problems.2 It may be either unilateral or bilateral, with different sizes, and may compromise the anatomy and function of the ostiomeatal complex. Pneumatization of the superior turbinate, which is also called concha bullosa of the superior turbinate by Stammberger,3 is a very rare entity, and only a few cases have been reported. 3,4 Pneumatization of the inferior turbinate has not yet been reported in the world literature. In this article, a patient with inferior turbinate pneumatization is presented.


Auris Nasus Larynx | 1999

Malondialdehyde levels and superoxide dismutase activity in experimental maxillary sinusitis

Fehmi Döner; Namik Delibas; Harun Doğru; İbrahim Sarı; Birdal Yorgancıgil

OBJECTIVE Acute maxillary sinusitis is one of the most common diseases in human. Reactive oxygen metabolites (ROMs) produced also physiologically in the body, are normally neutralised by antioxidative enzymes such as superoxide dismutase (SOD). Infection is one of the causes of increased ROMs production. The most important mechanism of tissue damage produced by ROMs is the peroxidation of lipids found in cell membranes and it may be estimated by malondialdehyde (MDA) levels. The purpose of this study, is to investigate tissue damage caused by ROMs in maxillary sinusitis in 24 rabbits. METHODS Experimental sinusitis was induced by blocking the right nose and inoculating Staphylococcus aureus into the right maxillary sinuses. Left maxillary sinuses were the control group. Animals were divided into three groups and killed at 3, 5 and 7 days. Mucosas of each maxillary sinus were examined histopathologically and MDA levels were determined. Blood samples were obtained preoperatively (control blood) and on killing days (experimental blood). Serum MDA levels and erythrocyte SOD activities were determined. RESULTS All the infected sinuses displayed signs of the inflammation. MDA levels and SOD activities in the experimental blood samples were significantly higher than those of the control group (P < 0.05). Mucosal MDA levels in the experimental group were significantly higher than the controls (P < 0.01). CONCLUSIONS In maxillary sinusitis caused by S. aureus an increased ROMs production was observed and it may contribute to tissue damage of sinusitis.


Otolaryngology-Head and Neck Surgery | 2005

What Is the Relationship Between Chronic Sinus Disease and Isolated Nasal Septal Deviation

Hasan Yasan; Harun Doğru; Bahattin Baykal; Fehmi Döner; Mustafa Tüz

Objective The aim of this retrospective study is to examine the role of isolated nasal septal deviation (NSD) in the pathogenesis of chronic rhinosinusitis (CRS). Study Design and Setting The interaction between isolated NSD and chronic sinus disease were retrospectively evaluated in 1452 patients. Out of 1452 patients, 152 patients were included in the study. Patients with anatomical variants other than NSD were excluded from the study. Patients with NSD were enrolled in the study group and patients without NSD were enrolled in the control group. Results There was no statistically significant difference between NSD group and non-NSD group with respect to the CRS. Conclusions The mild to moderate degree of NSD was not a risk factor for chronic sinus disease. Only gross deviation of the nasal septum itself is a risk factor for the development of CRS. Significance Excluding the subjects with ostiomeatal anatomic variations has differentiated this study from the previously reported researches (isolated NSD).


Journal of basic and clinical physiology and pharmacology | 2002

The role of free oxygen radicals in experimental otitis media.

Fehmi Döner; Namik Delibas; Harun Doğru; Murat Yariktas; Mustafa Demirci

Free oxygen radicals (FORs); have been implicated as important pathologic mediators in many diseases. Under physiological conditions FORs are part of normal regulatory circuits and neutralized by antioxidants, but an increased flux of FORs can cause tissue damage. Infections are one cause of increased FORs production. An important mechanism of tissue damage produced by FORs is the peroxidation of membrane lipids, which can be estimated by malondialdehyte (MDA) levels. The purpose of this study was to determine in 24 albino rabbits whether FORs play a role in the pathogenesis of otitis media experimentally induced by inoculating Streptococcus pneumonia into the right ear, with the left ear serving as a control. We examined the mucosa of each middle ear histopathologically and measured MDA levels in mucosa and serum. Serum MDA levels in infected rabbits were significantly higher than those in preoperative blood specimens (p<0.05). The MDA levels in mucosa were significantly higher in infected ears than in control ears (p<0.01). In the experimentally infected group, a correlation was found between MDA levels in serum and mucosa (p<0.05). In conclusion, serum and mucosa MDA indicating FORs production increased significantly in experimental otitis media. We considered that FORs might play a role in tissue damage caused by otitis media.


Otolaryngology-Head and Neck Surgery | 2005

Nitric oxide level in the nasal and sinus mucosa after exposure to electromagnetic field

Murat Yariktas; Fehmi Döner; Fehmi Ozguner; Osman Gokalp; Harun Doğru; Namik Delibas

OBJECTIVE: The purpose of this study was to examine the changes in nitric oxide (NO) level in the nasal and paranasal sinus mucosa after exposure radiofrequency electromagnetic fields (EMF). STUDY DESIGN AND SETTING: Thirty male Spraque-Dawley rats were randomly grouped as follows: EMF group (group I; n, 10), EMF group in which melatonin received (group II; n, 10) and the control (sham operated) group (group III; n, 10). Groups I and II were exposed to a 900 MHz. Oral melatonin was given in group II. Control rats (group III) were also placed in the tube as the exposure groups, but without exposure to EMF. At the end of 2 weeks, the rats were sacrificed, and the nasal and paranasal sinus mucosa dissected. NO was measured in nasal and paranasal mucosa. RESULTS: The nasal and paranasal sinus mucosa NO levels of group I were significantly higher than those of the control group (group III) (P < 0.05). However, there was no statistically significant difference between group II and the control group (group III) regarding NO output (P > 0.05). CONCLUSION: Exposure to EMF released by mobile phones (900 MHz) increase NO levels in the sinus and nasal mucosa. SIGNIFICANCE: Increased NO levels may act as a defense mechanism and presumably related to tissue damage. In addition, melatonin may have beneficial effect to prevent these changes in the mucosa. (Otolaryngol Head Neck Surg 2005; 132: 713-6.)


American Journal of Rhinology | 2007

Relationship between Toxocara seropositivity and allergic rhinitis.

Murat Yariktas; Mustafa Demirci; Giray Aynali; Selcuk Kaya; Fehmi Döner

Background Allergic rhinitis is the most common chronic disease in the upper respiratory tract, requiring better diagnostic methodology to counteract its onslaught. The purpose of this study was to investigate the association between Toxocara seropositivity and allergic rhinitis. Methods Sixty-four consecutive patients with allergic rhinitis and 61 healthy volunteers in the control group were included in this study. The diagnosis of allergic rhinitis was defined by positive epicutaneous prick test. The diagnosis of toxocariasis was established by IgG and specific IgE antibodies against Toxocara by ELISA method. All cases were examined for intestinal parasites also. The seropositive cases with Toxocara were reevaluated for symptoms and signs of toxocariasis. Results Higher toxocariasis seropositivity (ELISA IgG; 28.1%) rate was determined in the patients with allergic rhinitis and compared with the control groups (11.5%; p < 0.05). Specific IgE seropositivity (17.2%) was high for the patients with allergic rhinitis compared with the control group (3.3%; p < 0.05). Conclusion Our results show that there was a possible causal relationship between Toxocara infection and allergic rhinitis. Patients with allergic rhinitis from a region with high prevalence for this parasitic infection should be evaluated for Toxocara infection.


American Journal of Rhinology | 2005

The effect of topical corticosteroid on basic fibroblast growth factor in nasal polyp tissue.

Murat Yariktas; Fehmi Döner; Recep Sutcu; Mustafa Demirci; Harun Doğru; Hasan Yasan

Background The etiology of nasal polyposis and pathophysiological mechanisms of polyp formation is still poorly understood. Experimental models have suggested that nasal polyp growth requires extracellular matrix formation and is associated with fibroblast proliferation. Intranasal corticosteroids appear to be useful in reducing nasal polypoid lesions and the likelihood of polyp recurrence after surgery. Basic fibroblast growth factor (bFGF) is a potent angiogenesis factor and is mitogenic for a wide range of cell types. We investigated the alteration of bFGF levels in nasal polyp tissue after administration of topical corticosteroid. Methods Nasal polyp tissues were obtained from 36 patients with diffuse nasal polyposis before and after topical nasal steroid treatment. As a topical nasal steroid mometasone furoate was given for 4 weeks in a dosage of 200 μg/day. The bFGF levels were measured by competitive enzyme immunoassay method. Results The mean levels of tissue bFGF, before and after topical nasal steroid treatment, were 1485 ± 826 ng/mg protein (range, 416–3434 ng/mg) and 1340 ± 749 ng/mg protein (range, 330–3288 ng/mg), respectively. The levels of bFGF in nasal polyps were significantly lower than those before treatment after administration of topical nasal steroid (p = 0.011). Conclusion Administration of topical nasal steroid decreases bFGF levels of nasal polyp. It may be suggested that one of the effects in diminishing the size of nasal polyps is by decreasing the bFGF.


Otolaryngology-Head and Neck Surgery | 2003

The biochemical analysis of tympanosclerotic plaques

Fehmi Döner; Murat Yariktas; Harun Doğru; Hafize Uzun; Seval Aydin; Namik Delibas

OBJECTIVE We conducted a biochemical analysis of tympanosclerotic (TS) plaques. METHODS Forty-five samples containing TS plaques were obtained from 45 patients. Qualitative and quantitative biochemical analyses were performed. TS plaques were evaluated macroscopically in respect to color and structure. RESULTS Phosphate, calcium, ammonium, and cholesterol were detected in 44, 43, 35, and 7 samples, respectively. Mean calcium and phosphate levels and protein levels of samples were 2.5 +/- 2.6 mg/100 mg tissue, 0.16 +/- 0.11 mg, and 3.4 +/- 3.4 mg, respectively. TS plaques were dirty white in 20 samples, brunette in 13, yellowish in 4, white in 7, and brown in 1. The structure of TS plaques was hard in consistency in 23 samples, fibrous in 14 samples, and soft in 8 samples. CONCLUSION The wider range of values and different mineral contents in our series might be explained by the fact that we had a much larger variety of tissues in various stages of the TS process. The color and the consistency of TS plaques are due to the discrepancy in their content and the amount of mineral, cholesterol, and protein.


Journal of Laryngology and Otology | 2006

Incus and stapes necrosis associated with diabetes mellitus.

Mustafa Tüz; Harun Doğru; Hasan Yasan; Fehmi Döner; Murat Yariktas

Chronic otitis media is often associated with ossicular defects, the most frequent being necrosis of the long process of incus. Except for infection and cholesteatoma; trauma and local pressure by chorda tympani are uncommon causes leading to incus erosion. In the literature, no case of incus necrosis has been reported associated with type II diabetes mellitus (DM). A patient is presented in this report with incus and stapes suprastructure necrosis and associated type II DM who was admitted to the out-patient clinic with complaints of conductive hearing loss.

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Harun Doğru

Süleyman Demirel University

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Murat Yariktas

Süleyman Demirel University

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Namik Delibas

Süleyman Demirel University

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Mustafa Tüz

Süleyman Demirel University

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Orhan Gedikli

Süleyman Demirel University

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Hasan Yasan

Süleyman Demirel University

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Mustafa Demirci

Süleyman Demirel University

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Giray Aynali

Süleyman Demirel University

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Kemal Uygur

Süleyman Demirel University

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Ibrahim Sari

University of Gaziantep

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