Network


Latest external collaboration on country level. Dive into details by clicking on the dots.

Hotspot


Dive into the research topics where Bulent Unal is active.

Publication


Featured researches published by Bulent Unal.


Journal of Gastroenterology and Hepatology | 2007

Factors affecting mortality and morbidity in patients with peptic ulcer perforation

Belma Kocer; Suleyman Surmeli; Cem Solak; Bulent Unal; Betül Bozkurt; Osman Yildirim; Mete Dolapci; Omer Cengiz

Background and Aim:  With the introduction of H2 receptor antagonists and proton pump inhibitors, the incidence of elective surgery for peptic ulcer (PU) diseases has decreased, although complications of PU such as perforation and bleeding have remained fairly constant. The purpose of this study was to identify the risk factors that predict morbidity and mortality in patients with perforated PU.


Ejso | 2010

Validation of breast cancer nomograms for predicting the non-sentinel lymph node metastases after a positive sentinel lymph node biopsy in a multi-center study

A.S. Gur; Bulent Unal; U. Ozbek; Vahit Ozmen; F. Aydogan; S. Gokgoz; Bahadir M. Gulluoglu; E. Aksaz; Serdar Özbaş; S. Baskan; Ayhan Koyuncu; A. Soran

OBJECTIVE In the study, our aim was to evaluate the predictability of four different nomograms on non-sentinel lymph node metastases (NSLNM) in breast cancer (BC) patients with positive sentinel lymph node (SLN) biopsy in a multi-center study. METHODS We identified 607 patients who had a positive SLN biopsy and completion axillary lymph node dissection (CALND) at seven different BC treatment centers in Turkey. The BC nomograms developed by the Memorial Sloan Kettering Cancer Center (MSKCC), Tenon Hospital, Cambridge University, and Stanford University were used to calculate the probability of NSLNM. Area under (AUC) Receiver Operating Characteristics Curve (ROC) was calculated for each nomogram and values greater than 0.70 were accepted as demonstrating good discrimination. RESULTS Two hundred and eighty-seven patients (287) of 607 patients (47.2%) had a positive axillary NSLNM. The AUC values were 0.705, 0.711, 0.730, and 0.582 for the MSKCC, Cambridge, Stanford, and Tenon models, respectively. On the multivariate analysis; overall metastasis size (OMS), lymphovascular invasion (LVI), and proportion of positive SLN to total SLN were found statistically significant. We created a formula to predict the NSLNM in our patient population and the AUC value of this formula was 0.8023. CONCLUSIONS The MSKCC, Cambridge, and Stanford nomograms were good discriminators of NSLNM in SLN positive BC patients in this study. A newly created formula in this study needs to be validated in prospective studies in different patient populations. A nomogram to predict NSLNM in patients with positive SLN biopsy developed at one institution should be used with caution.


Journal of Clinical Gastroenterology | 2004

A confirmatory report for the close interaction of Helicobacter pylori with gastric epithelial MUC5AC expression.

Belma Kocer; Murat Ulaş; Yücel Üstündağ; Sibel Erdogan; Melih Karabeyoğlu; Osman Yldrm; Bulent Unal; Omer Cengiz; Atilla Soran

Background: Helicobacter pylori (H. pylori) infection is associated with the development of gastritis and peptic ulcer and is presumed to be a risk factor for low-grade B-cell lymphoma and gastric cancer. H. pylori also causes critical alterations in gastric mucin structure. Our aim was to determine the effect of H. pylori on MUC1, MUC2, and MUC5AC expression. Methods: Thirty H. pylori–positive and 15 H. pylori–negative antral gastric endoscopic biopsy specimens were evaluated for MUC1, MUC2, and MUC5AC expression with immunohistochemical staining. From the same specimens, we scrutinized the presence of H. pylori infection by hematoxylin and eosin and immunohistochemical staining. Results: In H. pylori infected patients, the expression of MUC5AC was found to be localized to the cells in the superficial epithelium and upper parts of the gastric glands. The number of MUC5AC-expressing cells and the staining intensity of MUC5AC were shown to decrease in patients with H. pylori infection. Histopathology and immunostaining patterns of gastric mucins implied that H. pylori was physically associated with extracellular MUC5AC and MUC5AC-producing cells. H. pylori infection does not significantly affect staining intensity and patterns of MUC1 and MUC2 expressions. MUC1 was not found in dysplastic tissues or intestinal metaplasia areas. MUC5AC was expressed in dysplastic areas, but not in intestinal metaplasia. MUC2 was expressed in both dysplastic and intestinal metaplasia areas. Conclusion: H. pylori decreases the amount of MUC5AC expression. With reducing MUC5AC-producing cells and MUC5AC mucin, H. pylori may potentially cause significant alterations of the structure and function of gastric mucins. H. pylori–dependent inhibition of mucin synthesis deserves more investigations to clarify the role of H. pylori and gastric MUC5AC interaction.


Journal of Investigative Surgery | 2006

The Role of Serum Inflammatory Markers in Acute Appendicitis and Their Success in Preventing Negative Laparotomy

Osman Yildirim; Cem Solak; Belma Kocer; Bulent Unal; Melih Karabeyoğlu; Betül Bozkurt; Sabahat Aksaray; Omer Cengiz

Improving the diagnosis of acute appendicitis in order to prevent unnecessary surgery is crucial. This study was intended to identify the role of serum inflammatory markers in patients with preliminary diagnosis of acute appendicitis with a retrospective design. Eighty-five patients with the preliminary diagnosis of acute appendicitis were recruited in this study within the period of November–December 2003. The avarage age was 31.8 years (ranged from 15 to 85). There were 62 males (72.9%) and 23 females (27.1%). In addition to performing routine tests, preoperative serum samples were obtained from the patients to measure C-reactive protein, interleukin-6, and interleukin-10. All the patients were operated on for a clinical suspicion of acute appendicitis. Depending on the macroscopic evidence during the operation and the histopathological examination of the specimen, the patients were separated into two groups: the ones who did not have acute appendicitis as the cause for acute abdomen (group I; n = 14) and the ones who had acute appendicitis (group II; n = 71). The ones who had acute appendicitis (group II) were further grouped as noncomplicated appendicitis (group IIA; n = 44) and complicated appendicitis (group IIB; n = 27). Being a male with elevated levels of leukocytes (white blood cells, WBC); C-reactive protein (CRP), interleukin-6 (IL-6); and interleukin-10 increased the probability of having acute appendicitis in patients with evidences of acute abdomen. The risk of complication of acute appendicitis significantly increased when patients had increased levels of C-reactive protein, increased erythrocyte sedimentation rate, and increased interleukin-6 levels, had symptoms for more than 24 h, and were female. Interleukin-10 levels within normal range might be helpful in eliminating the possibility of acute appendicitis. Thus, elevated levels of WBC, IL-6 and CRP might be helpful in confirming a potential diagnosis of acute appendicitis. In addition, normal levels of IL-10 might be of additional help to possibly rule out the diagnosis of acute appendicitis.


Journal of Medical Case Reports | 2008

Subcutaneous hydatid cysts occurring in the palm and the thigh: two case reports

Abuzer Dirican; Bulent Unal; Cuneyt Kayaalp; Vedat Kirimlioglu

IntroductionHydatid cyst disease is common in some regions of the world and is usually located in the liver and lungs. This report presents two cases of primary hydatid cysts located subcutaneously: one in the medial thigh and one in the left palm between the index and middle fingers.Case presentationsA 64-year-old male farmer visited our hospital because a swelling on the right medial thigh had grown during the last year. Superficial ultrasound and computed tomography revealed a lesion resembling a hydatid cyst. A germinative membrane was encountered during surgical excision. Pathological examination was compatible with a hydatid cyst. The second case involved a 67-year-old male farmer who complained of a swelling that had grown in his left palm in the last year. The preliminary diagnosis was a lipoma. However, a hydatid cyst was diagnosed during surgical excision and after the pathological examination. The patient did not have a history of hydatid cyst disease and hydatid cysts were not detected in other organs. There has been no disease recurrence after following both patients for 3 years.ConclusionA hydatid cyst should be considered in the differential diagnosis of subcutaneous cystic lesions in regions where hydatid cysts are endemic, and should be excised totally, with an intact wall, to avoid recurrence.


Surgery Today | 2011

Acute traumatic diaphragmatic ruptures: A retrospective study of 48 cases

Abuzer Dirican; Mehmet Yilmaz; Bulent Unal; Turgut Piskin; Veysel Ersan; Sezai Yilmaz

PurposeTraumatic diaphragmatic rupture (TDR) is associated with high rates of morbidity and mortality, and the preoperative diagnosis is difficult.MethodsForty-eight patients with TDR were treated in our department between January 2000 and May 2009. The cause, location, size of rupture, associated morbidity and mortality, surgical material for repair, and predictive factors for overall outcome were evaluated.ResultsThere were 41 male patients (85%) and 7 female patients (15%) with a mean age of 33.8 years (range 17–69 years). Blunt trauma accounted for the injuries of 15 patients (31%) and 33 patients (68%) had penetrating injuries. The diagnosis was preoperatively established in 12 patients (25%) with a plain chest X-ray or/and computed tomography. The location of rupture was on the left side of the diaphragm in 35 patients (73%), on the right side in 10 (21%), and was bilateral in 3 patients (6%). Traumatic diaphragmatic rupture was repaired with interrupted nonabsorbable sutures or polypropylene mesh (8 patients). Postoperative complications were observed in 18 patients (38%). Overall mortality was observed in 7 patients (15%). The mortality was associated with hemorrhagic shock (P = 0.002), a high injury severity score (P = 0.002), and having additional injuries (P = 0.015).ConclusionThe outcome of the patients is associated with presence of hemorrhagic shock, a high injury severity score, and additional organ injury.


Transplantation Proceedings | 2013

Hepatic Artery Thrombosis–Related Risk Factors After Living Donor Liver Transplantation: Single-Center Experience From Turkey

Bulent Unal; F. Gonultas; Cemalettin Aydin; Emrah Otan; Cuneyt Kayaalp; Sezai Yilmaz

AIM The purpose of this retrospective study is to evaluate the risk factors hepatic artery thrombosis (HAT) after orthotopic liver transplantation (OLT) in a consecutive series from a single center. MATERIALS AND METHODS Between January 2010 and May 2012, we performed 278 living donor liver transplantations, including 189 males and 89 females. We compared the risk factors between HAT and non-HAT groups according to the following variables: age, gender, body mass index (BMI), graft weight, use of graft, Child-Pugh and model for end stage liver disease score, level of hemoglobin, blood pressure, operation time, blood transfusion, presence of ascites, international normalized ratio (INR) level, and etiology. RESULTS Eighteen patients, including 15 males and 3 female, had HAT after the operation (mean age, 45.1 years; age range, 22-60 years). There were no pediatric patients in the HAT group. HAT rate was 6.5% in our series. Graft loss and retransplantation due to HAT was 38.7% in a 2-year period. Biliary leakage was observed in 72 (25.8%) living donor liver transplantations; this rate was higher in patients with HAT (n = 8; 44.4%). The infection rate was 50% (n = 9) in the HAT group and was 32.7% (n = 91) in the non-HAT group. Mean INR value was 2.15 in the HAT group and 1.72 in the non-HAT group. When we compared the groups according to use of graft for anastomosis, biliary lekage, infection, and INR value, the differences were statistically significant (P < .05). CONCLUSION Although the results of OLT have improved over the past years, HAT is still associated with substantial morbidity, high incidence of graft failure, and high mortality rates. The most important findings associated with HAT in our series were found as INR levels, bile leakage, and resistant infections. Use of vascular graft for hepatic artery anastomosis was found to increase HAT risk.


Journal of Medical Case Reports | 2009

Isolated cecal necrosis mimicking acute appendicitis: a case series.

Abuzer Dirican; Bulent Unal; Nuray Bassulu; Faik Tatli; Cemalettin Aydin; Cuneyt Kayaalp

IntroductionSpontaneous non-occlusive ischemic colitis involving the cecum alone (isolated cecal necrosis) is a rare condition that is generally due to a low-flow state: shock. It presents with right lower quadrant abdominal pain and may resemble acute appendicitis. Little is known about postoperative ischemic necrosis of the remaining colon after surgical treatment of isolated cecal necrosis. We report four cases of isolated cecal necrosis mimicking acute appendicitis seen at our institution within a 4-year period.Case presentationThe patients were two men and two women with a mean age at diagnosis of 59 years (range 46-68). The patients were of Turkish ethnic origin. All patients presented to the emergency room with acute abdominal pain and had symptoms of nausea and vomiting. The medical histories for three of the patients revealed end-stage renal failure requiring hemodialysis. The other patient had chronic obstructive pulmonary disease. Right hemicolectomy with anastomosis was performed in three patients and cecal resection with ileocolostomy was performed in the remaining one patient. All of the patients healed without complications. Median follow-up of patients was 24.5 (range: 17-37) months. There was no recurrence of ischemia in the remaining colon during the follow-up period of the patients.ConclusionIsolated cecal infarction should be included in the differential diagnosis of acute pain in the right lower quadrant of the abdomen, especially in those patients on chronic hemodialysis. While diffuse ischemic disease of the intestine has high morbidity, mortality and recurrence rates, patients with isolated cecal necrosis have a good prognosis with early diagnosis and surgical treatment compared to those with diffuse ischemic disease.


European Journal of Trauma and Emergency Surgery | 2010

Ruptured Hydatid Cysts into the Peritoneum: A Case Series.

Abuzer Dirican; Mehmet Yilmaz; Bulent Unal; Faik Tatli; Turgut Piskin; Cuneyt Kayaalp

Introduction:The rupture of a hydatid cyst into the abdominal cavity is a rare and serious complication.Methods:In this retrospective study, we evaluated ten patients who were surgically treated for ruptured hydatid cysts into the peritoneum at a university hospital in an endemic area between 2003 and 2008.Results:There were three female and seven male patients, with a mean age of 34.2 years (range 20–79). Ruptured cysts were located in the liver (7), pelvis (2), and spleen (1). Eight patients had other nonperforated hydatid cysts. Perforations were spontaneous in seven patients and traumatic in three. Patients’ diagnoses were done with abdominal ultrasound (3), computed tomography (6), and laparotomy (1). The surgical treatment of perforated cysts were radical (pericystectomy) in one patient and conservative (partial pericystectomy) in the other nine patients. There was postoperative morbidity (surgical site infection) in one patient and one postoperative recurrence of disease in another patient. Mortality was seen in one patient 2 months after operation due to pulmonary hydatid cyst and infection.Conclusion:The rupture of hydatid cysts into the peritoneal cavity should be included in the differential diagnosis of acute abdominal pain in endemic areas. Perforation in a young patient may be the first presentation of hydatid cyst. Multiple hydatid cysts may be a predisposing factor for perforation. Location of the cyst on segment VI of the liver may be a predisposing factor as well. Emergency surgery is the main treatment for intraperitoneal rupture of hydatid cysts and medical treatment should be given postoperatively.


Surgical Innovation | 2009

Ethyl pyruvate protects colonic anastomosis from ischemia-reperfusion injury.

Bulent Unal; M. Karabeyoglu; T. Huner; Emel Canbay; A. Eroglu; O. Yildirim; M. Dolapci; A. Bilgihan; O. Cengiz

Ethyl pyruvate is a simple derivative in Ca+2- and K+-containing balanced salt solution of pyruvate to avoid the problems associated with the instability of pyruvate in solution. It has been shown to ameliorate the effects of ischemia-reperfusion (I/R) injury in many organs. It has also been shown that I/R injury delays the healing of colonic anastomosis. In this study, the effect of ethyl pyruvate on the healing of colon anastomosis and anastomotic strength after I/R injury was investigated. Anastomosis of the colon was performed in 32 adult male Wistar albino rats divided into 4 groups of 8 individuals: (1) sham-operated control group (group 1); (2) 30 minutes of intestinal I/R by superior mesenteric artery occlusion (group 2); (3) I/R+ ethyl pyruvate (group 3), ethyl pyruvate was administered as a 50-mg/kg/d single dose; and (4) I/R+ ethyl pyruvate (group 4), ethyl pyruvate administration was repeatedly (every 6 hours) at the same dose (50 mg/kg). On the fifth postoperative day, animals were killed. Perianastomotic tissue hydroxyproline contents and anastomotic bursting pressures were measured in all groups. When the anastomotic bursting pressures and tissue hydroxyproline contents were compared, it was found that they were decreased in group 2 when compared with groups 1, 3, and 4 (P < .05). Both anastomotic bursting pressure (P = .005) and hydroxyproline content (P < .001) levels were found to be significantly increased with ethyl pyruvate administration when compared with group 2. When ethyl pyruvate administration doses were compared, a significant difference was not observed (P > .05). Ethyl pyruvate significantly prevents the delaying effect of I/R injury on anastomotic strength and healing independent from doses of administration.

Collaboration


Dive into the Bulent Unal's collaboration.

Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar

Atilla Soran

University of Pittsburgh

View shared research outputs
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Researchain Logo
Decentralizing Knowledge