Impact of lymph node ratio on survival in stage III ovarian high-grade serous cancer: a Turkish Gynecologic Oncology Group study

Ali Ayhan,Nazlı Topfedaisi Ozkan,Mustafa Erkan Sarı,Husnu Celik,Murat Dede,Özgür Akbayır,Kemal Güngördük,Hanifi Şahin,Ali Haberal,Tayfun Güngör,Macit Arvas,Mehmet Mutlu Meydanlı 대한부인종양학회 2018 Journal of Gynecologic Oncology Vol.29 No.1

Objective: The purpose of this study was to investigate the prognostic value of lymph node ratio (LNR) in patients with stage III ovarian high-grade serous carcinoma (HGSC). Methods: A multicenter, retrospective department database review was performed to identify patients with ovarian HGSC at 6 gynecologic oncology centers in Turkey. A total of 229 node-positive women with stage III ovarian HGSC who had undergone maximal or optimal cytoreductive surgery plus systematic lymphadenectomy followed by paclitaxel plus carboplatin combination chemotherapy were included. LNR, defined as the percentage of positive lymph nodes (LNs) to total nodes recovered, was stratified into 3 groups: LNR1 (<10%), LNR2 (10%≤LNR<50%), and LNR3 (≥50%). Kaplan-Meier method was used to generate survival data. Factors predictive of outcome were analyzed using Cox proportional hazards models. Results: Thirty-one women (13.6%) were classified as stage IIIA1, 15 (6.6%) as stage IIIB, and 183 (79.9%) as stage IIIC. The median age at diagnosis was 56 (range, 18–87), and the median duration of follow-up was 36 months (range, 1–120 months). For the entire cohort, the 5-year overall survival (OS) was 52.8%. An increased LNR was associated with a decrease in 5-year OS from 65.1% for LNR1, 42.5% for LNR2, and 25.6% for LNR3, respectively (p<0.001). In multivariate analysis, women with LNR≥0.50 were 2.7 times more likely to die of their tumors (hazard ratio [HR]=2.7; 95% confidence interval [CI]=1.42–5.18; p<0.001). Conclusion: LNR seems to be an independent prognostic factor for decreased OS in stage III ovarian HGSC patients.

Experimental verification of interleaved hybrid DC/DC boost converter

Celik, M. Ali,Genc, Naci,Uzmus, Hasan The Korean Institute of Power Electronics 2022 JOURNAL OF POWER ELECTRONICS Vol.22 No.10

In this study, an improved interleaved hybrid DC/DC boost converter used for high-power applications with high voltage gain was proposed. The proposed DC/DC boost converter increases low-input voltage to the desired high-output voltage with a wide duty cycle range through the hybrid structure, thereby prolonging the lifetime of the proposed converter by decreasing the current on circuit components. An extra filter for input current ripples is unnecessary. The proposed converter is less complex and has easier control than the converters used for high voltage gain. The proposed converter was operated when the duty cycle (d) was larger and smaller than 0.5. It was also analyzed theoretically, and the average- and small-signal circuits were obtained to show its stability. The proposed converter was controlled with the conventional control method by using a modern digital signal processor TMS320F28379D board. The proposed converter and its controller were operated under different conditions.

Impact of lymph node ratio on survival in stage IIIC endometrioid endometrial cancer: a Turkish Gynecologic Oncology Group study

Ali Ayhan,Nazlı Topfedaisi Ozkan,Murat Özdemir,Günsu Kimyon Comert,Zeliha Firat Cuylan,Gonca Çoban,Osman Turkmen,Baki Erdem,Hanifi Şahin,Özgür Akbayır,Murat Dede,Ahmet Taner Turan,Husnu Celik,Tayfun G 대한부인종양학회 2018 Journal of Gynecologic Oncology Vol.29 No.4

OBJECTIVE: The purpose of this study was to investigate the prognostic value of lymph node ratio (LNR) in women with stage IIIC endometrioid endometrial cancer (EC). METHODS: A multicenter, retrospective department database review was performed to identify patients with stage IIIC pure endometrioid EC at 6 gynecologic oncology centers in Turkey. A total of 207 women were included. LNR, defined as the percentage of positive lymph nodes (LNs) to total nodes recovered, was stratified into 2 groups: LNR1 (≤0.15), and LNR2 (>0.15). Kaplan-Meier method was used to generate survival data. Factors predictive of outcome were analyzed using Cox proportional hazards models. RESULTS: One hundred and one (48.8%) were classified as stage IIIC1 and 106 (51.2%) as stage IIIC2. The median age at diagnosis was 58 (range, 30-82) and the median duration of follow-up was 40 months (range, 1-228 months). There were 167 (80.7%) women with LNR ≤0.15, and 40 (19.3%) women with LNR >0.15. The 5-year progression-free survival (PFS) rates for LNR ≤0.15 and LNR >0.15 were 76.1%, and 58.5%, respectively (p=0.045). An increased LNR was associated with a decrease in 5-year overall survival (OS) from 87.0% for LNR ≤0.15 to 62.3% for LNR >0.15 (p=0.005). LNR >0.15 was found to be an independent prognostic factor for both PFS (hazard ratio [HR]=2.05; 95% confidence interval [CI]=1.07-3.93; p=0.03) and OS (HR=3.35; 95% CI=1.57-7.19; p=0.002). CONCLUSION: LNR seems to be an independent prognostic factor for decreased PFS and OS in stage IIIC pure endometrioid EC.

A Fuzzy TOPSIS Approach Based on Trapezoidal Numbers to Material Selection Problem

Celik, Erkan,Gul, Muhammet,Gumus, Alev Taskin,Guneri, Ali Fuat Korea Data Strategy Society 2012 Journal of information technology applications & m Vol.19 No.3

Material selection is a complex problem in the design and development of products for diverse engineering applications. This paper is aimed to present a fuzzy decision making approach to deal with the material selection in engineering design problems. A fuzzy multi criteria decision-making model is proposed for solving the material selection problem. The proposed model makes use of fuzzy TOPSIS (Technique for Order reference by Similarity to Ideal Solution) with trapezoidal numbers for evaluating the criteria and ranking the alternatives. And result is compared with fuzzy VIKOR (VlseKriterijumska Optimizacija I Kompromisno Resenje in Serbian, means Multi criteria Optimisation and Compromise Solution) which is proposed by Jeya Girubha and Vinodh [2012]. The present paper is aimed to also improve literature of fuzzy decision making for material selection problem.

A Fuzzy TOPSIS Approach Based on Trapezoidal Numbers to Material Selection Problem

Erkan Celik,Muhammet Gul,Alev Taskin Gumus,Ali Fuat Guneri 한국데이타베이스학회 2012 Journal of information technology applications & m Vol.19 No.3

Material selection is a complex problem in the design and development of products for diverse engineering applications. This paper is aimed to present a fuzzy decision‐making approach to deal with the material selection in engineering design problems. A fuzzy multi criteria decision‐making model is proposed for solving the material selection problem. The proposed model makes use of fuzzy TOPSIS (Technique for Order reference by Similarity to Ideal Solution) with trapezoidal numbers for evaluating the criteria and ranking the alternatives. And result is compared with fuzzy VIKOR (VlseKriterijumska Optimizacija I Kompromisno Resenje in Serbian, means Multi criteria Optimisation and Compromise Solution) which is proposed by Jeya Girubha and Vinodh [2012]. The present paper is aimed to also improve literature of fuzzy decision making for material selection problem.

Development of a knowledge‐based medical expert system to infer supportive treatment suggestions for pediatric patients

Duygu Celik Ertugrul,Ali Hakan Ulusoy 한국전자통신연구원 2019 ETRI Journal Vol.41 No.4

This paper discusses the design, implementation, and potential use of an ontology‐based mobile pediatric consultation and monitoring system, which is a smart healthcare expert system for pediatric patients. The proposed system provides remote consultation and monitoring of pediatric patients during their illness at places distant from medical service areas. The system not only shares instant medical data with a pediatrician but also examines the data as a smart medical assistant to detect any emergency situation. In addition, it uses an inference engine to infer instant suggestions for performing certain initial medical treatment steps when necessary. The applied methodologies and main technical contributions have three aspects: (a) pediatric consultation and monitoring ontology, (b) semantic Web rule knowledge base, and (c) inference engine. Two case studies with real pediatric patients are provided and discussed. The reported results of the applied case studies are promising, and they demonstrate the applicability, effectiveness, and efficiency of the proposed approach.

Molecular Characterization of Antibiotic Resistant Escherichia coli Strains Isolated from Tap and Spring Waters in a Coastal Region in Turkey

Ozgumus, Osman Birol,Celik-Sevim, Elif,Alpay-Karaoglu, Sengul,Sandalli, Cemal,Sevim, Ali The Microbiological Society of Korea 2007 The journal of microbiology Vol.45 No.5

A hundred and seventeen antibiotic-resistant Escherichia coli strains were isolated from public tap and spring waters which were polluted by fecal coliforms. There were no significant differences between two water sources as to the coliform pollution level (p> 0.05). All E. coli isolates were detected to be resistant to one or more antibiotics tested. Nearly 42% of the isolates showed multiresistant phenotype. Three (2.5%) of these isolates contained class 1 integron. Sequencing analysis of variable regions of the class 1 integrons showed two gene cassette arrays, dfr1-aadA1 and dhfrA17-aadA5. Resistance to ampicillin, tetracycline or trimethoprim-sulfamethoxazole was transferable according to the results of conjugation experiments. The rate of tetracycline resistance was 15%. tet(A)-mediated tetracycline resistance was widespread among tetracycline-resistant E. coli isolates. Genotyping by BOX-polymerase chain reaction (BOX-PCR) showed that some of the strains were epidemiologically related. This is the first report on the prevalence and characterization of class 1 integron-containing E. coli isolates of environmental origin in Turkey.

Exposure of Surgical Staff to Radiation During Surgical Probe Applications in Breast Cancer

Recep Bekis,Pinar Celik,Banu Uysal,Mehmet Ali Kocdor,Ali Sevinc,Serdar Saydam,Omer Harmancioglu 한국유방암학회 2009 Journal of breast cancer Vol.12 No.1

Purpose: The aim of study was to determine the level of the radiation exposure of surgical staff during surgical probe applications in breast cancer. Methods: Three operations of a sentinel lymph node biopsy were randomly selected. Spaced circles (50 cm apart) were drawn surrounding the operation bed on the floor. Tc-99m nanocolloid was injected peritumorally and intradermally into a patient. The radiation dose was measured with a GeigerMueller counter placed according to the drawn circles at distances of 50-200 cm from the side of patient's head and bilateral chest while the patient lay on the operation bed. All of the surgical procedures were recorded with a video camera and were monitored. Results: The whole body dose to the senior surgeon was calculated as 2.00-4.70 µSv which means that a senior surgeon can perform 212-500 procedures per year to reach the annual International Commission on Radiological Protection radiation dose limit for a member of the public. Conclusion: We concluded that radiation risk to the surgical staff is low from sentinel node detection with the use of radiocolloids.

The Constituents of Essential Oil: Antimicrobial and Antioxidant Activity of Micromeria congesta Boiss. & Hausskn. ex Boiss. from East Anatolia

Emine Nur Herken,Ali Celik,Mustafa Asl,Nilüfer Aydınlık 한국식품영양과학회 2012 Journal of medicinal food Vol.15 No.9

The chemical composition, antimicrobial activity, total phenol content, total antioxidant activity, and total oxidant status of the essential oil from Micromeria congesta Boiss. & Hausskn. ex Boiss. were investigated. Steam distillation was used to obtain the essential oil, and the chemical analyses were performed by gas chromatography–mass spectrometry. The antimicrobial activity was tested by an agar disc diffusion method against the tested microorganisms: Bacillus subtilis NRRL B-744, Bacillus cereus NRRL B-3711, Staphylococcus aureus ATCC 12598, S. aureus ATCC 25923, S. aureus ATCC 25933, Escherichia coli 0157H7, E. coli ATCC25922, Micrococcus luteus NRLL B-4375, Enterococcus faecalis ATCC 19433, Proteus vulgaris RSKK 96026, and Yersinia enterecolitica RSKK 1501. The major compounds found in volatiles of M. congesta were piperitone oxide, linalool oxide, veratrole, pulegone, dihydro carvone, naphthalene, iso-menthone, para-menthone, and cyclohexanone. Compared to that of reference antibiotics, the antibacterial activity of the essential oil is considered as significant. Results showed that M. congesta has the potential for being used in food and medicine depending on its antioxidant and antibacterial activity.

Molecular Characterization of Antibiotic Resistant Escherichia coli Strains Isolated from Tap and Spring Waters in a Coastal Region in Turkey

Osman Birol Ozugumus,Elif Celik-Sevim,Sengul Alpay-Karaoglu,Cemal Sandalli,Ali Sevim 한국미생물학회 2007 The journal of microbiology Vol.45 No.5

A hundred and seventeen antibiotic-resistant Escherichia coli strains were isolated from public tap and spring waters which were polluted by fecal coliforms. There were no significant differences between two water sources as to the coliform pollution level (p> 0.05). All E. coli isolates were detected to be resistant to one or more antibiotics tested. Nearly 42% of the isolates showed multiresistant phenotype. Three (2.5%) of these isolates contained class 1 integron. Sequencing analysis of variable regions of the class 1 integrons showed two gene cassette arrays, dfr1-aadA1 and dhfrA17-aadA5. Resistance to ampicillin, tetracycline or trimethoprim-sulfamethoxazole was transferable according to the results of conjugation experiments. The rate of tetracycline resistance was 15%. tet(A)-mediated tetracycline resistance was widespread among tetracycline-resistant E. coli isolates. Genotyping by BOX-polymerase chain reaction (BOX-PCR) showed that some of the strains were epidemiologically related. This is the first report on the prevalence and characterization of class 1 integron-containing E. coli isolates of environmental origin in Turkey.