Person: ERMERAK, NEZİH ONUR
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ERMERAK
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NEZİH ONUR
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Publication Open Access Esophageal perforation during intragastric balloon therapy: management of a patient with late referral(2023-01-01) ERMERAK, NEZİH ONUR; UPRAK, TEVFİK KIVILCIM; LAÇİN, TUNÇ; YILDIZELİ, BEDRETTİN; YEGEN, ŞEVKET CUMHUR; ERMERAK N. O., Uprak K. T., Emran M., LAÇİN T., YILDIZELİ B., YEGEN Ş. C.Minimally invasive treatment modalities like intragastric balloon therapy (IBT) gained popularity in the treatment of obesity [1]. Some morbidities have been reported in the literature, but it is limited. Esophageal perforation is the most feared complication of the procedure. Although endoscopic stent placement can be chosen as a treatment option in stable patients, most of the patients are treated with surgical drainage and primary repair [2]. We report an unusual case of intragastric balloon placement complicated with esophageal perforation which was successfully treated with a surgical approach after late referral.Publication Open Access Clinical validation of an activity-based enzyme assay for early stage lung cancer(2023-06-02) ERMERAK, NEZİH ONUR; Dempsey P., Sandu Aparacio C., Gonzalezirias R., Hantula S., Kagawa M., Bossmann S. H., Covarrubias-Zambrano O., Nagji A. S., Veeramachaneni N. K., ERMERAK N. O., et al.Background: The USPSTF guidelines recommend annual LDCT scans for 15.5 million adults with a heavy smoking history. While LDCT can reduce deaths by 20%, screening compliance remains low. A blood test with clinically useful, cost effective performance could improve compliance and access when integrated with the standard of care. We describe here a lyophilized nanosensor system for detecting protease enzyme activity in sera with clinically useful diagnostic activity in early stage lung cancer. We evaluated the performance of the assay by examination of prospectively collected sera for detection of cancer in high risk patients. Methods: Sera were obtained in multiple independent studies to include pathologically confirmed, treatment naive lung cancer patients and LDCT confirmed negative individuals. Protease activity was measured on 18 different nanosensors built with protease targets mainly selective for members of the Matrix Metalloproteinase and Cathepsin families. Lyophilized plates were incubated with serum and enzyme activity was measured indirectly as a continuous variable by a fluorescent plate reader. A machine learning modeling tool (Emerge) was used to detect signal associated with a cancer “fingerprint” of protease activity. The analysis stratified allocation into training and testing sets of 250 samples each and reserved a third out of sample validation set (250 samples) for reporting. Results: 750 clinical samples included 30% lung cancers, 63% males, 91% smokers, and an average age of 63 years (SD=9). Cancer cases were distributed across stages I (41%), II (17%), III (20%) and IV (20%) with 5% unknown. Histological classification included 59% adenocarcinoma, 31% squamous cell and 11% other subtypes. Using an Emerge model with only nanosensor activity and gender as inputs, we evolved a balanced algorithm. The algorithm can be further modified to favor sensitivity or specificity depending on the application by applying model weighting factors. We report the performance observed in the 250 out of sample validation set at three points on this spectrum (Table). Among Stage I cancer samples, the balanced algorithm had an accuracy of 90% (26/29). Conclusions: Current LDCT tools show low compliance. We demonstrate clinical validity of a cost effective tool to detect lung cancer in support of LDCT screening. Based on a simple blood sample, the current test may predict early stage lung cancer with an accuracy of 90%. The performance suggests applications in LDCT compliance, post LDCT management, and eventually screening. A clinically validated version of this technology is being evaluated as a triage tool for LDCT screening.Publication Open Access Surgical outcomes of patients with non-small cell lung cancer following neoadjuvant treatment(MARMARA UNIV, FAC MEDICINE, 2018-10-31) ERMERAK, NEZİH ONUR; Ocakcioglu, Ilhan; Alpay, Levent; Ermerak, Nezih Onur; Kiral, Hakan; Tezel, Cagatay; Baysungur, Volkan; Yalcinkaya, IrfanObjective: Although, anatomical resection of non-small cell lung cancer (NSCLC) following neoadjuvant therapy is still controversial, it is a widely accepted approach for thoracic surgery practice. The aim of this study is to briefly evaluate clinical results, long term survival, and factors affecting survival of the patients with locally advanced NSCLC, pancoast tumour and lung cancer with solitary brain metastasis, who have been operated at our institution following neoadjuvant therapy. Materials and Method: Between March 2006 and March 2012, 70 patients with NSCLC diagnosis who underwent anatomic pulmonary resection following neoadjuvant therapy were included in the study. Results: A three year survival (39%) and a 5-year survival (29%) were 16 +/- 6.8 and 37 +/- 9.89 months, respectively. The mean survival was found to be 37.15 +/- 3.06 months. When survival rate was evaluated according to localization of tumor, it was lower in central and left upper lobe tumors compared to other anatomical localizations (P=0.042). The mean 5-year survival times were 50.00 +/- 5.65 months in stage 0 patients, 35.39 +/- 5.85 months in stage 1 patients, 37.40 +/- 6.89 months in stage 2 patients and 21.44 +/- 3.10 months in stage 3 patients. Conclusion: We can achieve significant survival results by the anatomical pulmonary resection following neoadjuvant therapy.Publication Open Access The angiogenic gene profile of pulmonary endarterectomy specimens: Initial study(2023-01-01) ERMERAK, NEZİH ONUR; YILMAZ, BETÜL; BATIREL, SAİME; OLGUN YILDIZELİ, ŞEHNAZ; KOCAKAYA, DERYA; MUTLU, BÜLENT; YILDIZELİ, BEDRETTİN; ERMERAK N. O., YILMAZ B., BATIREL S., OLGUN YILDIZELİ Ş., KOCAKAYA D., MUTLU B., Tas S., YILDIZELİ B.© 2023 The Author(s)Objectives: The underlying mechanisms for the development of chronic thromboembolic pulmonary hypertension and prognostic biomarkers are not clear yet. Thus, our aim is to assess and identify new biomarkers for the expression of 84 key genes linked to angiogenesis. Methods: Patients who had levels more than 1000 dynes·sec·cm−5 were included in the test group, and the other patients were included in the control group. Twelve specimens were taken from the patients. RT2 Profiler PCR Array (Qiagen) was used to quantify the expression of the 84 key genes. Results: Eight patients (6 male, 2 female, median age 54.4 ± 13.1 years) who underwent pulmonary endarterectomy were included. Pulmonary vascular resistance improved significantly from 811 ± 390 dyn/s/cm−5 to 413.3 ± 144.9 dyn/s/cm−5 (P .005) after surgery. Median length of hospital stay was 11.62 ± 2.97 days. The test group had a distinct pattern of impaired angiogenic and antiangiogenic genes. The expression levels of TGFA, TGFB1, THBS2, THBS1, TGFBR1, SERPINE1, SERPINF1, TGFB2, TIMP2, VEGFC, IFNA1, TNF, CXCL10, NOS3, IGF1, and MMP14 were downregulated in the specimens from the patients who had higher pulmonary vascular resistance values, whereas some genes, including PDGFA, showed upregulation that was statistically nonsignificant in the same group. Conclusions: These results can lead to the development of new markers that could predict adverse outcomes of patients with CTEPH. Identification of new markers that are related to worse outcomes would enable screening patients for early diagnosis and treatment.Publication Open Access Minimally Invasive Repair of Pectus Carinatum(ELSEVIER SCIENCE INC, 2018-03) ERMERAK, NEZİH ONUR; Yuksel, Mustafa; Lacin, Tunc; Ermerak, Nezih Onur; Sirzai, Esra Yamansavci; Sayan, BihterBackground. The second most common deformity of the anterior chest wall, pectus carinatum, is a diverse deformity that has been largely managed using open techniques. This study reviews clinical experience with a newly designed bar for minimally invasive repair of pectus carinatum. Methods. We reviewed the records of all patients recorded in our Chest Wall Deformities Clinical Database. Between January 2006 and November 2016, minimally invasive repair of pectus carinatum was performed in 172 patients. All met the criteria of a compression test of 10 to 25 kg/cm(2). The mean age was 17.3 years, and 22.7% had a positive family history of a congenital chest wall deformity. Symmetric and asymmetric deformities were treated. During our study period, we designed 4 different bar configurations and their related stabilizers. All patients are assessed every 3 to 6 months. After 2 to 3 years of follow-up, the bar and the stabilizers are removed. Results. Of 172 patients, 97.1% tolerated the procedure very well. The operation was a mean length 76.6 minutes. Average blood loss was 40 mL. Mean hospital length of stay was 3.7 days. Complications included pneumothorax, wire breakdown/rib cut, wound infection, severe pain, skin hyperpigmentation, nickel allergy, and overcorrection leading to excavatum. Patients returned to routine activity in 10 to 14 days. With a mean follow-up of 29.8 months in bar removal patients, 130 of 172 (93.8%) reported excellent results. Conclusions. Minimally invasive repair of pectus carinatum with the technically modified fourth-generation bar and its securing system has advantages of low morbidity, short hospital stay, and excellent cosmetic results, even in asymmetric cases. (C) 2018 by The Society of Thoracic SurgeonsPublication Open Access Refractory invasive aspergillosis controlled with posaconazole and pulmonary surgery in a patient with chronic granulomatous disease: case report(BIOMED CENTRAL LTD, 2014-12) KEPENEKLİ KADAYİFCİ, EDA; Kepenekli, Eda; Soysal, Ahmet; Kuzdan, Canan; Ermerak, Nezih Onur; Yuksel, Mustafa; Bakir, MustafaInvasive aspergillosis is an important cause of morbidity and mortality in immunocompromised patients. Among primary immunodefiencies, chronic granulomatous disease (CGD) has the highest prevalence of invasive fungal diseases. Voriconazole is recommended for the primary treatment of invasive aspergillosis in most patients. In patients whose aspergillosis is refractory to voriconazole, therapeutic options include changing class of antifungal, for example using an amphotericin B formulation, an echinocandin, combination therapy, or further use of azoles. Posaconazole is a triazole derivative which is effective in Aspergillosis prophylaxis and treatment. Rarely, surgical therapy may be needed in some patients. Lesions those are contiguous with the great vessels or the pericardium, single cavitary lesion that cause hemoptysis, lesions invading the chest wall, aspergillosis that involves the skin and the bone are the indications for surgical therapy. Chronic granulomatous disease (CGD) is an inherited immundeficiency caused by defects in the phagocyte nicotinamide adenine dinucleotidephosphate (NADPH) oxidase complex which is mainstay of killing microorganisms. CGD is characterized by recurrent life-threatening bacterial and fungal infections and by abnormally exuberant inflammatory responses leading to granuloma formation, such as granulomatous enteritis, genitourinary obstruction, and wound dehiscence. The diagnosis is made by neutrophil function testing and the genotyping. Herein, we present a case with CGD who had invasive pulmonary aspergillosis refractory to voriconazole and liposomal amphotericine B combination therapy that was controlled with posaconazole treatment and pulmonary surgery.Publication Open Access Total Rib Resection Via Uniportal Thoracoscopic Approach(2018-10) ERMERAK, NEZİH ONUR; Ocakcıoglu, Ilhan; Ermerak, Nezih Onur; Yuksel, MustafaPublication Open Access Risk of serious perioperative complications with removal of double bars following the Nuss procedure(OXFORD UNIV PRESS, 2016-10-20) ERMERAK, NEZİH ONUR; Bilgi, Zeynep; Ermerak, Nezih Onur; Cetinkaya, Cagatay; Lacin, Tunc; Yuksel, MustafaOBJECTIVES: The aim of this study is to present our experience with Nuss bar removal and evaluate potential risk factors. The Nuss procedure requires an operation to remove the bar 2-3 years after the initial correction. Although removal of the bar is generally believed to be safe, perioperative complications including major bleeding can occur. METHODS: All cases involving removal of the Nuss bar done since April 2007 were recorded in a prospective database. Data were collected on the amount of blood loss, the number of diagnostic interventions, operative management and postoperative course. RESULTS: Of a total of 246 ( 162 with single bars, 80 with double bars, 4 with triple bars) cases, 43 patients (17.5%) experienced perioperative complications. Five patients underwent secondary postoperative interventions; one patient required same-session emergency videoassisted thoracic surgery (VATS) due to major bleeding. Patients who had complications were significantly older than patients with no complications (20.5 +/- 6.5 years vs 17.2 +/- 5.9 years, P = 0.002). People having double bars removed were significantly more likely to have perioperative complications (12% vs 27%, P = 0.03) and complications requiring secondary interventions (n = 1 for a single bar, n = 5 for double bars, P = 0.01). CONCLUSIONS: Major complications after removal of the Nuss bar occur with some frequency. Although the double-bar removals in our cohort were associated with major complications, the reasons are poorly understood. Immediate management of the complications may require multidisciplinary care. Multicentric pooling of cases is needed for better risk stratification.Publication Open Access Production of 3D-printed ribs with a novel material (Nylon 680 Co-Polymer) for chest wall reconstruction on a pig model: Preliminary results of an experimental study(2023-09-01) ERMERAK, NEZİH ONUR; LAÇİN, TUNÇ; ERBARUT SEVEN, İPEK; ERMERAK N. O., YÜKSEL M., Yüksel B., LAÇİN T., ERBARUT SEVEN İ., LAÇİN B.Aim: Three-dimensional (3D) printing has gained popularity among all fields of science in recent years. New research studies about the utilization of 3D printing in the medical field, in terms of medical devices and implants, have been published recently. We tried to adapt this technology into thoracic surgery by implanting 3D produced ribs following chest wall resection with a novel material called Nylon 680 Co-Polymer. We, hereby, present the preliminary results of this experimental study. Materials and Methods: We ordered multi detector computerized tomography of the chest for 2 pigs. We measured the area that we planned to resect on chest wall and used the data for printing custom-made rib for the reconstruction of the resected area. Then, we produced ribs with a USA Food and Drug Administration approved material called Nylon 680 Co-polymer (Taulman 3D, Saint Peters, MO, USA) by using 3D printer (Afinia H480, Chanhassen, MO, USA). Pigs were operated under general anesthesia and the resected areas were reconstructed with custom-made 3D printed ribs. Results: One of the pigs passed away due to myocardial infarction while waking up from anesthesia. We followed up the other pig for 45 days. Then, we sacrificed the animal and resected the operated part for histopathological evaluation. Histopathologic evaluation revealed moderate chronic inflammation with few giant cells containing pigmented foreign bodies. Conclusion: Although we need more studies, it is an important step for adapting 3D-printing into thoracic surgery. Additionally, it is important to identify a potential new material (Nylon 680 Co-polymer) for the future studies. We can use this new material for 3D-printed implant and mesh production, which enables us to produce custom-made products with lower cost in shorter timePublication Open Access Do Nuss bars compromise the blood flow of the internal mammary arteries?(OXFORD UNIV PRESS, 2013-09) YILDIZELİ, BEDRETTİN; Yuksel, Mustafa; Ozalper, Mehmet Hakan; Bostanci, Korkut; Ermerak, Nezih Onur; Cimsit, Cagatay; Tasali, Nuri; Yildizeli, Bedrettin; Batirel, Hasan FevziOBJECTIVES: Minimally invasive repair of pectus excavatum, the so-called Nuss procedure, has become a popular technique in recent years. The internal mammary arteries (IMAs) lie on the posterolateral surface of the sternum, and the Nuss bar is likely to obstruct the blood flow in these arteries. This obstruction could become important in the later stages of the lives of these young people if they were to require coronary artery bypass grafting. The goal of this study is to investigate the extent of obstruction of the IMAs caused by Nuss bars. METHODS: Data were collected prospectively on all patients who underwent the Nuss procedure between October 2011 and May 2012. Patients with a history of pectus excavatum repair by open surgery and those who were younger than 16 years of age were excluded. Computed tomography-angiography (CTA) was performed for the detection of IMA blood flow preoperatively and on the 10th postoperative day. Blood flow in the IMAs was evaluated blindly by two radiologists and classified as blood flow unaffected (group I) or affected (group II) by comparing the assessment of preoperative and postoperative CTAs. The patients in group II were also categorized as having blood flow obstructed bilaterally, blood flow obstructed unilaterally and others (diminished unilaterally/diminished on one side or obstructed on the other side). RESULTS: Thirty-four patients (31 male and three female; mean age 20.7 +/- 4.2 years) underwent surgery. Blood flow was affected in 15 patients (44%), with bilateral obstruction in five, unilateral obstruction in seven, and unilateral diminished flow in two patients. In one patient, blood flow was diminished on one side and obstructed on the other. There was no significant difference between unaffected group I patients and affected group II patients in terms of sex, age, type of deformity, Haller index and the number of bars placed. CONCLUSIONS: Nuss bars cause pressure on the IMAs, but a risk factor for this effect could not be identified. This is a relatively common clinical consequence of minimally invasive repair of pectus excavatum, and the long-term effects will be apparent following bar removal.