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Dive into the research topics where Koray Öcal is active.

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Featured researches published by Koray Öcal.


Biochemical Genetics | 2005

Glutathione S-transferase M1, T1, P1 genotypes and risk for development of colorectal cancer.

Nurcan Aras Ateş; Lülüfer Tamer; Cengiz Ateş; Bahadır Ercan; Tufan Elipek; Koray Öcal; Handan Camdeviren

The glutathione S-transferase (GST) supergene family is an important part of cellular enzyme defense against endogenous and exogenous chemicals, many of which have carcinogenic potential. The present investigation was conducted to detect a possible association between polymorphisms at the GSTM1, GSTT1, and GSTP1 genes and the interaction with cigarette smoking and colorectal cancer incidence. We examined 181 patients with colorectal cancer and 204 controls. DNA was extracted from whole blood, and the GSTM1, GSTT1, and GSTP1 polymorphisms were determined using a real-time polymerase chain reaction and fluorescence resonance energy transfer with a Light-Cycler instrument. Associations between specific genotypes and the development of colorectal cancer were examined by use of logistic regression analysis to calculate odds ratios (OR) and 95% confidence intervals (CI). The GSTM1 polymorphism was associated with an increased risk of developing colorectal cancer (OR = 1.62, 95% CI: 1.06–2.46). Also the risk of colorectal cancer associated with the GSTT1 null genotype was 1.64 (95% CI: 1.10–2.59). Statistically no differences were found between patients with colorectal cancer and control groups for the GSTP1 Ile/Ile, Ile/Val and Val/Val genotypes. In addition, the frequencies of the GSTM1 and GSTT1 deletion genotypes differed significantly between the cases and controls for current smokers; the GSTT1 null genotype especially is associated with a greater risk of colorectal cancer (OR = 2.44, 95% CI: 1.24–4.81). The GSTM1 and GSTT1 deletions were associated with an increased risk of developing a transverse or rectal tumor (OR = 1.86, 95% CI: 1.15–3.00; OR = 1.70, 95% CI: 1.02–2.84; respectively). The glutathione S-transferase polymorphisms were not associated with risk in patients stratified by age. The risk of colorectal cancer increased as putative high-risk genotypes increased for the combined genotypes of GSTM1 null, GSTT1 null, and either GSTP1 valine heterozygosity or GSTP1 valine homozygosity (OR = 2.69, 95% CI: 1.02–7.11). In conclusion, the results obtained in this study clearly suggest that those susceptibility factors related to different GST polymorphic enzymes are predisposing for colorectal cancer.


Breast Journal | 2010

Granulomatous Mastitis: Clinical, Pathological Features, and Management

Koray Öcal; Ahmet Dag; Ozgur Turkmenoglu; Tuba Kara; Hakan Seyit; Kamuran Konca

Abstract:  This clinical study was conducted to present clinical, radiologic, and histopathologic features of Granulomatous Mastitis (GM) and evaluate the result of surgical and steroid treatment. Sixteen cases diagnosed histologically as GM were reviewed. Patient characteristics, clinical presentation, radiologic imaging, microbiologic, histopathologic assessment, treatment modalities, recurrence, morbidity, and follow‐up data were analyzed. Majority of the patients were child bearing age and all of the patients had a history of breast feeding. Radiologic findings were nonspecific. Histopathology showed the characteristic distribution of granulomatous inflammation in all cases. In 12 cases, surgical excision of the lesion with negative margins was performed. Four cases required quadranectomy because of wideness of the disease. Three patients who had local reoccurrence and three resistant patients were treated by oral prednisone after surgical attempt. Complete remission was obtained and no further recurrence was observed in this patients. GM predominantly occurs in premenopausal women and the clinical symptoms might be misjudged as breast cancer. Histopathologic examination remains the gold standard for the diagnosis. Wide excision of the lesions is the recommended therapy and we suggest steroid therapy in resistant or recurrent disease following the idea that the disease has an autoimmune component.


Surgical Laparoscopy Endoscopy & Percutaneous Techniques | 2013

A prospective randomized comparison of single-port laparoscopic procedure with open and standard 3-port laparoscopic procedures in the treatment of acute appendicitis.

Alper Sözütek; Tahsin Colak; Musa Dirlik; Koray Öcal; Ozgur Turkmenoglu; Ahmet Dag

Background: This prospective randomized study aimed to evaluate the surgical outcomes of single-incision laparoscopic appendectomy (SILA) comparing with open appendectomy (OA) and standard 3-port laparoscopic appendectomy (SLA) in the treatment of acute appendicitis (AA). Methods: Adult patients older than 18 years presenting with AA were randomized into 3 groups to undergo OA, SLA, and SILA from September 2010 to May 2011. The groups were compared with regard of patient’s characteristics, perioperative findings/complications, operative time, pain severity, analgesic requirement, time to oral tolerance and flatus, length of hospital stay, and cosmetic results. Results: A total of 75 consecutive patients enrolled in the study. Each group included 25 patients. The groups showed no significant differences in patient’s characteristics. The mean operative time was significantly longer in SILA than OA with a mean difference of 7 minutes (P<0.05). Postoperative pain after OA were significantly higher than SLA and SILA (P<0.05). The average time to oral tolerance and flatus was significantly higher in OA than the laparoscopic groups with a mean difference of 1 and 2.5 hours (P=0.04 and 0.023, respectively). The length of hospital stay in SLA and SILA was significantly lower than OA with a mean difference of 0.8 days (P<0.05). There was no difference in overall complications between the groups. There was no difference between SLA and SILA in terms of surgical outcomes. Conclusions: Either SLA or SILA offer patients faster recovery period with acceptable complications than OA. Hence, laparoscopic approach might be considered as first option in the treatment of AA. However, all 3 techniques provide equivalent clinical outcomes despite the significant findings. Therefore, technique selection is based on surgeon’s decision, experience, and availability of laparoscopic instruments.


Journal of Zhejiang University-science B | 2008

Total thyroidectomy is safer with identification of recurrent laryngeal nerve

Hakan Canbaz; Musa Dirlik; Tahsin Colak; Koray Öcal; Tamer Akca; Öner Bilgin; Bahar Tasdelen; Suha Aydin

ObjectiveTo investigate the effect of recurrent laryngeal nerve (RLN) identification on the complications after total thyroidectomy and lobectomy.MethodsTotal 134 consecutive patients undergoing total thyroidectomy or thyroid lobectomy from January 2003 to November 2004 were investigated retrospectively. Patients were divided into two groups: RLN identified (Group A) or not (Group B). The two groups were compared for RLN injury and hypocalcaemia.ResultsThe numbers of patients and nerves at risk were 71 and 129 in Group A, and 63 and 121 in Group B, respectively. RLN injury in Group A (0) was significantly lower than that in Group B (5 [7.9%]) patients, 7 [5.8%] nerves) for the numbers of patients (P=0.016) and nerves at risk (P=0.006). Temporary hypocalcaemia was significantly higher in Group A than in Group B (14 [24.1%] vs 6 [10.3%], P=0.049). Permanent complications in Group B were significantly higher than those in Group A (13 [20.6%] vs 4 [5.6%], P=0.009).ConclusionRLN injury was prevented and permanent complications were decreased by identifying the whole course and branches of the recurrent laryngeal nerve during total thyroidectomy.


European Archives of Oto-rhino-laryngology | 2010

Level IIb lymph node metastasis in thyroid papillary carcinoma

Yusuf Vayisoglu; Cengiz Özcan; Ozgur Turkmenoglu; Kemal Görür; Murat Ünal; Ahmet Dag; Koray Öcal

The objective of the study was to evaluate the incidence of level IIb lymph node metastases in neck dissections for thyroid papillary carcinoma (TPC) patients. 47 neck dissections of 33 patients with TPC were prospectively evaluated. Selective neck dissections (levels II, III, IV, and V) were performed in all cases. If level I lymph node metastasis was suspected during the procedure, level I dissection was also performed. All level IIb specimens were sent separately from the remainder of the neck dissection for the pathological examination. The number of dissected and metastatic lymph nodes in each specimen was recorded. Twenty-two of 47 neck dissections (46.8%) were positive for the lymph node metastasis. Among 47 neck dissection specimens, the incidence of lymph node metastasis at level II was 12.7% (6 of 47) and level IIb was 2.1% (1 of 47). The rate of level IIb lymph node involvement among patients with metastatic cervical lymph nodes was 4.5% (1 of 22). The specimen with metastatic lymph node at level IIb had also metastasis at levels IIa, III, IV, and V. The results of the present study suggested that lymph node metastases in level IIb are rare in patients with TPC undergoing neck dissection.


Surgical Practice | 2012

Apocrine carcinoma of the male breast

Ahmet Dag; Ebru Serinsöz; Koray Öcal

Apocrine carcinoma of the male breast is an extremely rare tumour. Only two cases have been published in the medical literature. There is insufficient data about clinical presentation, management and prognostic features of apocrine carcinoma in the male breast. In this study, the clinical presentation, magnetic resonance imaging and histopathological features and management of a 76‐year‐old male with apocrine carcinoma in the left breast are discussed. We present, to best of our knowledge, the third case of apocrine carcinoma of the male breast in medical literature.


Pharmacological Research | 2003

The effect of PARS inhibition on ileal histopathology, apoptosis and lipid peroxidation in LPS-induced obstructive jaundice.

Musa Dirlik; Mehmet Caglikulekci; Ismail Cinel; Leyla Cinel; Lülüfer Tamer; Cengiz Pata; Arzu Kanik; Koray Öcal; Zekai Ogetman; Suha Aydin

In our experimental study, we investigated the protective effect of 3-aminobenzamide (3-AB), the poly (ADP-ribose) synthetase (PARS inhibitor), on the ileal histopathology and the apoptosis in lipopolysaccharide (LPS)-induced inflammation in rats with obstructive jaundice (OJ). We randomized 40 rats into five groups. Group 1: sham group; Group 2: OJ group; Group 3: OJ+LPS; Group 4: OJ+3-AB+LPS; Group 5: OJ+LPS+3-AB. At the fifth day; the rats were jaundiced. In Group 3; 10 mg kg(-1) LPS was injected intraperitoneally at the fifth day and then after 6h the rats were sacrificed. In Group 4; 10 mg kg(-1) 3-AB was administrated intraperitoneally at the fifth day and repeated daily for 3 days and at the eighth day, 10 mg kg(-1) LPS was injected intraperitoneally. In Group 5, 10 mg kg(-1) LPS was injected intraperitoneally at the fifth day and after 6h 10 mg kg(-1) 3-AB was administrated intraperitoneally and repeated daily for 3 days. At the eighth day, rats were sacrificed. Blood samples were taken for detection of serum MDA levels. Ileum samples were taken after relaparotomy for histopathological examination to evaluate the endotoxin-related intestinal injury and Caspase-3 apoptosis and for detection of tissue MDA and ATPase activities. There was marked destruction of villous and crypt epithelial cells and extensive apoptosis in Groups 3 and 5 in histopathological examination. In Group 4, the scores of intestinal mucosal damage and apoptotic cells were reduced significantly (P<0.05). On the other hand, the scores of intestinal mucosal damage and apoptotic cells were not improved in Group 5. After the administration of 3-AB (Group 4), serum and ileal MDA levels decreased, ileal ATPase increased as compared to Groups 1 and 2. Our study showed that 3-AB prevented the mucosal damage and apoptotic loss of intestinal epithelial cells significantly if it was administrated before LPS. However, 3-AB failed to prevent the mucosal damage and apoptotic loss of intestinal epithelial cells significantly if there was established endotoxemia in OJ.


Aesthetic Plastic Surgery | 2001

Endoscopic Balloon Dissection for Removal of Lipomas Via Transaxillary Route

Aydin Saray; Koray Öcal; Metin Berberoglu

Abstract. Minimally invasive techniques and newer endoscopic surgical techniques are being introduced to aesthetic and reconstructive procedures at an accelerating pace. A new and modified technique of endoscopic excision of large encapsulated lipomas is presented and the versatility of creation of an optical cavity and incorporation of balloon dissection is discussed in two cases. Large encapsulated lipomas were removed endoscopically via transaxillary incisions and no immediate or late complication was observed. Endoscopic removal of lipomas offers several advantages over conventional direct excision and liposuction such as avoiding blind manipulation and fragmentation of lipoma mass, and unsightly scars. One drawback of this technique can be lengthy operation times, which have been near two hours for the presented cases. We conclude that endoscopic removal of tumors from a relatively remote site is beneficial in treating such encapsulated tumors and we speculate that endoscopy will prevent unsightly scarring in important areas while decreasing the operating time as experience is gained.


Clinics | 2011

Radioguided occult lesion localization versus wire-guided localization for non-palpable breast lesions: randomized controlled trial

Koray Öcal; Ahmet Dag; Ozgur Turkmenoglu; Emel Ceylan Günay; Erdem Yucel; Meltem Nass Duce


Burns | 2004

The effect of N-acetylcysteine on oxidative stress in intestine and bacterial translocation after thermal injury

Koray Öcal; Dinçer Avlan; Ismail Cinel; Ali Unlu; Candan Öztürk; Faik Yaylak; Musa Dirlik; Handan Camdeviren; Suha Aydin

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