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Dive into the research topics where Ahmet Dirican is active.

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Featured researches published by Ahmet Dirican.


Helicobacter | 2006

Prevalence of Helicobacter pylori vacA , cagA , cagE , iceA , babA2 Genotypes and Correlation with Clinical Outcome in Turkish Patients with Dyspepsia

Y. Erzin; V. Koksal; S. Altun; A. Dobrucali; M. Aslan; S. Erdamar; Ahmet Dirican; Bekir Kocazeybek

Background:  Distinct virulence factors of Helicobacter pylori have been associated with clinical outcome of the infection; however, considerable variations have been reported from different geographic regions and data on genotypes of Turkish H. pylori isolates are sparse.


Forensic Science International | 2009

Higher prevalence of toxoplasmosis in victims of traffic accidents suggest increased risk of traffic accident in Toxoplasma-infected inhabitants of Istanbul and its suburbs ☆

Bekir Kocazeybek; Y.A. Oner; Recep Turksoy; Cahit Babür; Hüseyin Çakan; Nilgun Sahip; Ali Unal; Abdi Özaslan; Selçuk Kiliç; Suat Saribas; Mustafa Aslan; Aysegul Taylan; Sermet Koç; Ahmet Dirican; Hüseyin Bülent Üner; Vecdet Öz; Cemalettin Ertekin; Ömer Küçükbasmacı; Müzeyyen Mamal Torun

Reflexes of drivers who have toxoplasmosis have been shown to deteriorate from the actions of the parasitic cysts. The cysts can change the level of the neurotransmitters such as dopamine in the brain and by doing so extend the muscle response time and change personality profiles. In this study, we aimed to determine the frequency of the latent toxoplasmosis (LT) in the driver population who were either injured or died in traffic accidents reported in Istanbul and its suburbs. We compared the results with a control group and discussed the relationship between the LT and the traffic accidents. We included 218 (89.7%) non-fatal, 25 (10.3%) fatal cases in our study as study groups. A total 243 subjects, 234 (96%) male, 9 (4%) female (who were alcohol negative) compared with 191 (95.5%) male and 9 (4.5%) female subjects (control group) who had a traffic accident before but no history of toxoplasmosis were studied. Serologic tests, enzyme immunoassay (EIA) for IgG and IgM, and microimmunoflorescence (MIF) for IgG were used as the reference test, the Sabin-Feldman Dye test (SFDT) was used. According to serologic test results, LT seroprevalence in the study groups was 130 (53.5%) and in the control group 56 (28%) (p<0.0001). A LT was present in 126 out of 234 (53.8%) males in the study groups, and 54 out of 191 (28.3%) males in the control group (p<0.0001). In the 31-44 year age group, there was a significant difference with regard to toxoplasmosis between the study subjects and control groups (p<0.0001). This difference was statistically very significant in (recent and former) cases with middle-aged men (31-44 years old). The results of this retrospective study suggest that LT in drivers, especially those who are between 31 and 44 years might increase the risk for getting involved in a car accident. In a prospective study, Toxoplasma positive and negative subjects can be monitored before they are involved in a traffic accident to clarify the cause and result relationship.


Journal of Clinical Gastroenterology | 2008

Hyperhomocysteinemia in inflammatory bowel disease patients without past intestinal resections: correlations with cobalamin, pyridoxine, folate concentrations, acute phase reactants, disease activity, and prior thromboembolic complications.

Yusuf Erzin; Hafize Uzun; Aykut Ferhat Celik; Seval Aydin; Ahmet Dirican; Hülya Uzunismail

Objective Homocysteine is a sulfur-containing amino acid formed during the demethylation of methionine and high levels of this amino acid is a known risk factor for both arterial and also venous thromboembolic complications. Deficiencies of cobalamin, folate, and pyridoxine may predispose subjects to hyperhomocysteinemia, a common phenomenon in inflammatory bowel disease (IBD) patients. The aim of this study was to identify the prevalence, risk factors of hyperhomocysteinemia and its correlation with prior thromboembolic events in an IBD cohort without past intestinal resections. Methods In this prospective study, we studied the concentrations of homocysteine, cobalamin, folate, and pyridoxine in 105 consecutive patients with IBD, of whom 11 had a prior history of thromboembolic complications. Data regarding smoking habits, medication use, disease location, and severity were gathered and patients with past intestinal resections were excluded. Age-matched and sex-matched 85 healthy volunteers served as controls and multivariate regression analysis was performed to find out independent predictors of hyperhomocysteinemia. Results The mean age (±SD) in the IBD cohort was 38.69±12.13 years, and 51% were male. The mean age in the control group was 37.61±10.05 years, and 52% were male. Homocysteine concentrations in patients were higher [16.35 μmol/L (range 6.82 to 48.15) vs. 9.60 μmol/L (range 4.97 to 17.39), P=0.000] and hyperhomocysteinemia had a higher prevalence in patients than in the controls (56.2% vs. 4.7%, χ2=56.179, P=0.000), thus IBD significantly increased the risk of hyperhomocysteinemia [odds ratio=25.973 (95% confidence interval: 8.861-76.128)]. Homocysteine concentrations in patients with a history of thrombosis were not higher than those without a history of thrombosis [16.29 μmol/L (range 8.45 to 34.75) vs. 16.36 μmol/L (range 6.82 to 48.15), not significant]. Hyperhomocysteinemia was found in 54.5% of patients with thrombosis and 56.4% of patients without thrombosis (not significant). On stepwise regression analysis, plasma cobalamin level, albumin concentration, erythrocyte sedimentation rate, and platelet count were found to be independent predictors of elevated homocysteine levels. Conclusions IBD patients have a higher prevalence of hyperhomocysteinemia than do healthy controls and elevated homocysteine levels are independently associated with lower serum cobalamin, albumin levels and elevated erythrocyte sedimentation rate, and platelet count. There is no correlation between hyperhomocysteinemia and a history of prior thromboembolic events.


Helicobacter | 2004

Comparison of two Different Stool Antigen Tests for the Primary Diagnosis of Helicobacter pylori Infection in Turkish Patients with Dyspepsia

Y. Erzin; S. Altun; A. Dobrucali; M. Aslan; S. Erdamar; Ahmet Dirican; Bekir Kocazeybek

Aim.  To assess the reliability of two different enzyme immunoassays in detecting the Helicobacter pylori status in stool specimens of Turkish patients with dyspepsia.


Journal of Gastroenterology | 2008

Role of host interleukin 1β gene (IL-1B) and interleukin 1 receptor antagonist gene (IL-1RN) polymorphisms in clinical outcomes in Helicobacter pylori-positive Turkish patients with dyspepsia

Yusuf Erzin; Vedat Koksal; Sibel Altun; Ahmet Dobrucali; Mustafa Aslan; Sibel Erdamar; Süha Göksel; Ahmet Dirican; Bekir Kocazeybek

BackgroundHelicobacter pylori infection leads to different clinical outcomes depending on both host and bacterial factors. In a recent study, we identified H. pylori cagE and babA2 genotypes as independent predictors of duodenal ulcer (DU) and gastric cancer (GC) in dyspepsia patients, but no previous studies have examined the role of host-related genetic factors in Turkey. This time our aim was to evaluate whether polymorphisms of the interleukin 1B (IL-1B) and the interleukin 1 receptor antagonist (IL-1RN) genes are important factors in the differential expression of gastroduodenal diseases in H. pylori-positive dyspepsia patients.MethodsNinety-three H. pylori-positive patients, 30 with nonulcer dyspepsia (NUD), 30 with DU, and 33 with GC, were investigated. The IL-1B-511 and IL-1B-31 biallelic polymorphisms, and the IL-1RN intron 2 variable number tandem repeat were genotyped by polymerase chain reaction and single-strand confirmation polymorphism analysis.ResultsThe IL-1RN-1/1 genotype was significantly more prevalent among patients with NUD than among those with GC (χ2 = 9.270; P = 0.002), and the IL-1RN-1/2 genotype was significantly more common in patients with GC (χ2 = 6.01; P = 0.014). Multivariate regression analysis showed that cagE, babA2, and IL-1RN-1/2 genotypes were independent predictors of GC, but when patients with benign disorders were grouped together (NUD + DU) and compared with patients with GC, regression analysis disclosed that babA2 (P = 0.000) and IL-1B-31 gene polymorphisms (CC or CT) (P = 0.01) were the only independent markers of GC.ConclusionsWhen analyzed together with host genetic factors, the wellestablished bacterial risk factor babA2 seems to be the most important predictor of malignant disorders, and the presence of the IL-1B-31TT genotype emerges as a protective factor against them.


Rheumatology International | 2011

Do infections trigger juvenile idiopathic arthritis

Mustafa Aslan; Ozgur Kasapcopur; Hatice Yasar; Erdal Polat; Suat Saribas; Hüseyin Çakan; Ahmet Dirican; Müzeyyen Mamal Torun; Nil Arisoy; Bekir Kocazeybek

Juvenile idiopathic arthritis (JIA) is a disease that was prominent with increased inflammation response in immune system, appeared mostly with peripheral arthritis and endogenous and exogenous antigens play a role in the pathogenesis of disease. Two major reasons were thinking to be considerably important. First of them is immunological predisposition and the second one is environmental factors. Infections are considered to be the most important between environmental factors but also stress and trauma are also important in the etiology of the disease. However, the relation between JIA and infections is not clearly defined but the relation between adult chronic arthritis and infections was well-defined. A total of 70 patients, 26 with primer JIA, 20 with recurrent JIA, 24 healthy control were included in this study. Mycoplasma pneumoniae, Chlamydophila pneumoniae and C. Jejuni were detected in 4, 1 and 1 of 10 (38.46%) patients with primer JIA, respectively. Salmonella enteritidis, EBV, M. pneumoniae, C. jejuni and Borrelia burgdorferi were detected in 1, 2, 2, 2, and 1 of the 8(40%) patients with recurrent JIA, respectively. S. enteritidis were isolated in feces culture and also identified by agglutination method. Infection was detected in total 18 (39.13%) of patient groups. C. pneumoniae and C. jejuni were detected in 1 and 1 of 2(8.33) healthy control groups, respectively. Throat culture positivity was not detected in any of the patient and healthy control groups. In conclusion, etiopathogenesis of JIA is not clearly understood and suggested that various factors can trigger the disease and it is the most common rheumatoid disease of childhood. However, there are some studies focusing especially on one infectious agent but this is the first study including such a big range of infectious agents in the literature for the microorganisms that can be suggested to have a role in the etiopathogenesis of JIA. We have a conclusion in the light of our results and suggest that some microorganisms can trigger and increase the intensity of clinical situation according to the case. When we evaluate the primer and recurrent JIA groups; M. pneumoniae and C. jejuni come forward and seen common in JIA cases. We also suggest that the pre-diagnosis of microorganisms, which can play a role as primarily or by intervening in the etiopathogenesis of JIA and adding specific antimicrobial therapy to the standard JIA therapy, it is possible to perform new, extended, especially molecular based serial case studies.


Operations Research Letters | 2008

Comparison of the Long-Term Efficacy of Subcutaneous and Sublingual Immunotherapies in Perennial Rhinitis

Rauf Tahamiler; Gkioukxel Saritzali; Salih Canakcioglu; Engin Özcora; Ahmet Dirican

Background: Both sublingual and subcutaneous immunotherapies have a documented clinical efficacy, but only a few comparative studies have been performed. Objectives: To evaluate and compare the long-term efficacies of subcutaneous and sublingual immunotherapy. Methods: One hundred and ninety-three patients with house dust mite allergies, out of an original total of 230, were treated with subcutaneous and sublingual house dust mite-specific immunotherapies for 3 years and also observed for 3 years after discontinuation of the treatment. The patients were randomized into 2 groups: the sublingual group (97 patients) and the subcutaneous group (96 patients). The therapy’s success was evaluated using the symptom score, skin prick test results, and the nasal allergen challenge score. The patients were evaluated at the beginning of the study, at the end of years 1, 2, and 3, and also at the end of the 1st and 3rd years after discontinuation of the specific immunotherapy treatment. Results: Immunotherapy induced a significant improvement during the treatment and the follow-up period. We found a greater improvement in the subcutaneous group compared to the sublingual group when we looked at the comparative results of the total 6 years. Conclusion: We suggest subcutaneous immunotherapy for patients with perennial allergic rhinitis due to the better results that were obtained during our study period. Nevertheless, sublingual immunotherapy is now accepted by WHO as a valid alternative to the subcutaneous route and should be used in all patients who require immunotherapy and do not accept the subcutaneous route of allergen administration.


Childs Nervous System | 1995

Effects of carbamazepine and valproate on brainstem auditory evoked potentials in epileptic children

Adnan Yuksel; Dogan Senocak; Dilşat Sözüer; Gurkan Keskin; Ahmet Dirican; Asim Cenani; Erdinç Yalçin

Brainstem auditory evoked potentials (BAEPs) were recorded in 18 epileptic children receiving carbamazepine and 10 epileptic children receiving valproate. BAEPs were recorded before the administration of antiepileptic drugs (AEDs) and 13 months later during which the children received AEDs. Statistical analysis of peak latencies and interpeak intervals of waves I–III–V were made. Carbamazepine treatment resulted in prolongation of peak latencies of waves I–III–V and interpeak intervals I–III and I–V. Valproate monotherapy, on the other hand, caused no consistent changes on BAEP. On the basis of these results we suggest that chronic carbamazepine therapy exerts a suppressive influence on the auditory pathways, both peripherally at the level of the cochlea and/or auditory nerve, and centrally at the brainstem.


Laryngoscope | 2006

Nasal Sound Analysis: A New Method for Evaluating Nasal Obstruction in Allergic Rhinitis

Rauf Tahamiler; Deniz Tuna Edizer; Salih Canakcioglu; Melih Guven Guvenc; Ender Inci; Ahmet Dirican

Objective: Current measurements of nasal obstruction are unreliable and may be improved with the development of new techniques. The effectiveness of odiosoft‐rhino (OR) in the evaluation of nasal obstruction was investigated in a blind comparison at a referral center, institutional practice.


Archive | 2003

Effects of Hyaluronic Acid–Carboxymethylcellulose Antiadhesion Barrier on Ischemic Colonic Anastomosis

Süphan Ertürk; Serdar Yüceyar; Muhyittin Temiz; Baki Ekci; Nevin Sakoglu; Huriye Balci; Ahmet Dirican; Ali Cengiz; Haluk Saner

AbstractPURPOSE: Intraperitoneal adhesions may help the healing of marginally viable bowel ends. If adhesion formation is prevented by various methods, the integrity of ischemic bowel anastomosis may be compromised. Thus, we decided to study the effects of hyaluronic acid–carboxymethylcellulose, an antiadhesion barrier, on ischemic bowel anastomosis. METHODS: Thirty Wistar-Albino rats were divided into three groups. In Group A (control), a well-perfused distal colonic segment was transected, and free ends were anastomosed. In Group B, an ischemic colonic segment was prepared, then divided and anastomosed. In Group C, after completion of ischemic colonic anastomosis, hyaluronic acid–carboxymethylcellulose film was wrapped around the anastomosis. In all groups, rats were killed on the seventh day. Intraperitoneal adhesions were graded by adhesion score, and healing of the anastomosis was assessed by measurement of bursting pressure and hydroxyproline levels in the anastomotic tissue. RESULTS: A statistically significant difference was found between hydroxyproline levels of the control group and the ischemic group (P = 0.02). HP level was also significantly higher in the hyaluronic acid–carboxymethylcellulose group than in the ischemic group (P = 0.01). There was no difference in hydroxyproline levels between the control and hyaluronic acid–carboxymethylcellulose groups. Compared with the control group, bursting pressure was lower in the ischemic group (P = 0.02). Hyaluronic acid–carboxymethylcellulose wrapping increased the bursting pressure significantly (P < 0.001). However, there was no difference in bursting pressure between the control group and the hyaluronic acid–carboxymethylcellulose group (P = 0.13). A marked increase in the adhesion score was observed in the ischemic group (P = 0.01). The difference between adhesion scores of the hyaluronic acid–carboxymethylcellulose and ischemic groups was not found to be significant, although the adhesion score in the hyaluronic acid–carboxymethylcellulose group was lower (P = 0.16). There was no difference in adhesion score between the control and hyaluronic acid–carboxymethylcellulose groups. CONCLUSIONS: Application of hyaluronic acid–carboxymethylcellulose in ischemic colonic anastomosis did not compromise anastomotic integrity. The adverse effect of ischemia on healing of colonic anastomosis was counteracted by hyaluronic acid–carboxymethylcellulose.

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