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Öğe DRUG RESISTANCE RESTRICTS THE EFFICACY OF SHORT TERM LOW DOSE MITOMYCIN-C TREATMENT IN UMUC-3 BLADDER CANCER CELLS(Iniestares, S.A., 2018) Gul, Murat; Goktas, Serdar; Kars, Meltem Demirel; Kaynar, MehmetOBJECTIVE: Mitomycin-c (MMC) is the most used intravesical adjuvant agent in non-muscle invasive bladder cancer to prevent recurrence. However, a consensus on about appropriate dosage and treatment schedule of MMC is lacking. We, therefore, aimed to evaluate the most appropriate MMC dosage using an in vitro model of high-grade human bladder cancer. METHODS: UMUC-3 cells, a model for high-grade bladder cancer, were exposed to MMC in different time courses to assess its toxicological effects. XTT cell proliferation kit was used to evaluate the effect of MMC on the proliferation of UMUC-3 cell line. Gene expression analysis for the MDR1, BCL2 and ANXA5 genes was performed by Real-time PCR and flow cytometry analysis were conducted to evaluate the cell death mechanism and acquired resistance after MMC exposure. An ANXA5 kit was used to detect apoptotic cells, and 7-AAD was used to detect necrotic cells. RESULTS: Cell proliferation was prevented to a large extent (IC50, 0.175-0.081 mg/mL) and cytotoxic effects were observed after 5 mu g/mL and 10 mu g/mL MMC administrations for 1 and 2-h, after the 4th and 2nd dose cycles, respectively. Moreover, cell death was observed at 5 mu g/mL and 10 mu/mL MMC applications for 1-h and 2-h by the sixth and second week, respectively. Flow cytometry exhibits increased subpopulation of drug-extruding UMUC-3 cells after a single dose of MMC for 1-h. MMC did not increase the number of apoptotic or necrotic cells; yet, MDR1 (multiple drug resistance) and ANXA5 (apoptotic) expression levels were increased and BCL2 (anti-apoptotic) expression was decreased. Limitations: In-vitro nature of the study and working with only one cell culture are inherit limitations of this project. CONCLUSION: A single dose of MMC administration for 1 or 2-h results in drug-resistance. If maintenance treatment is administered for one hour, it should be continued throughout a 6-week period.Öğe Effective radiation exposure evaluation during a one year follow-up of urolithiasis patients after extracorporeal shock wave lithotripsy(Polish Urological Assoc, 2015) Kaynar, Mehmet; Tekinarslan, Erdem; Keskin, Suat; Buldu, Ibrahim; Soenmez, Mehmet Giray; Karatag, Tuna; Istanbulluoglu, Mustafa OkanIntroduction To determine and evaluate the effective radiation exposure during a one year follow-up of urolithiasis patients following the SWL (extracorporeal shock wave lithotripsy) treatment. Material and methods Total Effective Radiation Exposure (ERE) doses for each of the 129 patients: 44 kidney stone patients, 41 ureter stone patients, and 44 multiple stone location patients were calculated by adding up the radiation doses of each ionizing radiation session including images (IVU, KUB, CT) throughout a one year follow-up period following the SWL. Results Total mean ERE values for the kidney stone group was calculated as 15, 91 mSv (5.10-27.60), for the ureter group as 13.32 mSv (5.10-24.70), and in the multiple stone location group as 27.02 mSv (9.41-54.85). There was no statistically significant differences between the kidney and ureter groups in terms of the ERE dose values (p = 0.221) (p >0.05). In the comparison of the kidney and ureter stone groups with the multiple stone location group; however, there was a statistically significant difference (p = 0.000) (p <0.05). Conclusions ERE doses should be a factor to be considered right at the initiation of any diagnostic and/or therapeutic procedure. Especially in the case of multiple stone locations, due to the high exposure to ionized radiation, different imaging modalities with low dose and/or totally without a dose should be employed in the diagnosis, treatment, and follow-up bearing the aim to optimize diagnosis while minimizing the radiation dose as much as possible.Öğe Management of patients with retroperitoneal tumors and a review of the literature(Bmc, 2015) Gemici, Kazim; Buldu, Ibrahim; Acar, Turker; Alptekin, Husnu; Kaynar, Mehmet; Tekinarslan, Erdem; Karatag, TunaBackground: Retroperitoneal tumors (RTs) develop insidiously and are generally seen as large masses, and 50% of RTs are larger than 20 cm at the time of diagnosis. In this article, we share our experience of 5 years of surgical management of RTs. Methods: We evaluated 28 RT cases operated on in three education hospitals in Turkey from January 2008 onwards, with regard to patients' demographic characteristics, complaints, weight loss figures, the location and size of the tumor, blood transfusion, intra-operational time, metastases (in malignant cases), additional organ resection, histological grade, local recurrences, average life expectancy, and post-operative treatment methods. Results: The mean age of the patients was 49 years (range, 18 to 78 years). Twenty (71.43%) were female, and 8 (28.57%) were male. The primary complaint was abdominal pain in 18 patients (64.28%). CT scans were performed in 17 (61%) patients, 10 (35.4%) underwent abdominal MR imaging, and 1 (3.6%) underwent both abdominal CT and abdominal MR imaging. A mass was palpated in the pelvis (suprapubic region) in seven (25%) of the patients during physical examination. The largest tumors were detected in the left lumbar area. The mean tumor size was 12.78 cm (range, 2 to 30 cm). The mean intra-operational time was 192 min (range, 70 to 380 min). The mean hospitalization period was 11 days (range, 8 to 23 days). Seven (25%) patients were reported to have benign tumors, while 21 (75%) were reported to have malignant tumors. The most frequently seen malignant pathology was liposarcoma (eight cases; 38.09%) followed by leiomyosarcoma (five cases; 23.8%) and malignant fibrous histiocytoma (four cases; 19.04%). The earliest local recurrence was detected in the 12th month and the latest in the 28th month. A total of 11 (52.3%) of the total of 21 malignant cases experienced local recurrence within 3 years. The 3-year average life expectancy was 85.7% in the 18 malignant cases. Conclusions: Due to the low response rate of all but two types of RT to chemotherapy, the best remaining treatment option is surgery with wide resection margins, whereby all macroscopic traces of tumor are removed.Öğe Prematüre ejakülasyon (Erken boşalma) tedavisinde tramadol kullanımı(2010) Kaynar, Mehmet; Yurdakul, TalatPrematüre ejakülasyon dünyada standart tedavisi olmayan yaygın bir hastalıktır. Biz bu çalışmamızda Tek kör plasebo kontrollü yaşam boyu PE si olan 60 hastada on-demand tremadol kullanımın etkinlğini değerlendirdik. PE nin tanımlamasında ve tedavinin etkinliğinin ölçümünde IELT kullanıldı. 8 hafta süre ile 30 hastaya 25 mg tramadol ve 30 hastayada plasebo verildi. İlaçı cinsel ilşkiden 1-2 saat önce almaları önerildi. Tramadol ve plasebo tedavi sonrasında IELT sırasıyla 38.83 sn den 154.66 `sn ye 30.66' den 55.83 sn ye ye yükselmiştir bu iki grup arasındaki fark istatistiksel olarak anlamlı bulunmuştur(P < 0.0001).8 haftanın sonunda Tramadol ve plasebo grubunda boşalmayı kontrol edebilme becerisi, cinsel tatmin skorunda anlamlı yükselme gözlenmiştir ve bu oran istatistiksel olarak anlamlı bulunmuştur (P < 0.001).Öğe Prognostic value of preoperative neutrophil-to-lymphocyte and platelet-to-lymphocyte ratios, and multiphasic renal tomography findings in histological subtypes of renal cell carcinoma(Bmc, 2014) Keskin, Suat; Keskin, Zeynep; Taskapu, Hakan Hakki; Kalkan, Havva; Kaynar, Mehmet; Poyraz, Necdet; Toy, HaticeBackground: To determine the relationship between renal cell carcinoma subtypes and the associated mortality and biochemical parameters. An additional aim was to analyze multiphasic multidetector computed tomography findings. Methods: This study is a hospital-based retrospective investigation, using 211 patients with a diagnosis of renal cell carcinoma upon computed tomography examination. The histological subtypes included clear cell in 119 patients, chromophobe cell in 30 patients, papillary cell in 25 patients, mixed cell in 32 patients, and sarcomatoid cell in 4 patients. Results: The mean age of the patients participating in this study was 61.18 +/- 11.81 years, and the mortality rate was 10.4% (n = 22) through the 2-year follow-up. The ratios of both the neutrophil-to-lymphocyte upon admission to the hospital and platelet-to-lymphocyte of the non-surviving group were significantly higher than those of the surviving group (p < 0.05). When the analysis of the 2-year survival of the patients was examined according to the median platelet-to-lymphocyte ratio values, the Kaplan-Meier survival curves were significantly different between the surviving and non-surviving groups (p = 0.01). In two-way analysis of variance test, statistically significant results which were influenced by mortality (p = 0.028) and were found between renal cell carcinoma subtypes in the computed tomography density of corticomedullary phase (p = 0.001). Conclusions: The neutrophil-to-lymphocyte ratio and platelet-to-lymphocyte ratio may represent widely available biomarkers in renal cell carcinoma, and the logistic regression model indicated that neutrophil-to-lymphocyte ratio was a significant predictor for mortality. According to the median platelet-to-lymphocyte ratio values, the Kaplan-Meier survival curves were significantly different between the surviving and non-surviving groups.Öğe Texture analysis of multiparametric magnetic resonance imaging for differentiating clinically significant prostate cancer in the peripheral zone(Tubitak Scientific & Technological Research Council Turkey, 2023) Ozer, Halil; Koplay, Mustafa; Baytok, Ahmet; Seher, Nusret; Demir, Lutfi Saltuk; Kilincer, Abidin; Kaynar, MehmetBackground/aim: Texture analysis (TA) provides additional tissue heterogeneity data that may assist in differentiating peripheral zone (PZ) lesions in multiparametric magnetic resonance imaging (mpMRI). This study investigates the role of magnetic resonance imaging texture analysis (MRTA) in detecting clinically significant prostate cancer (csPCa) in the PZ.Materials and methods: This retrospective study included 80 consecutive patients who had an mpMRI and a prostate biopsy for sus-pected prostate cancer. Two radiologists in consensus interpreted mpMRI and performed texture analysis based on their histopathology. The first-, second-, and higher-order texture parameters were extracted from mpMRI and were compared between groups. Univariate and multivariate logistic regression analyses were performed using the texture parameters to determine the independent predictors of csPCa. Receiver operating characteristic (ROC) curve analysis was conducted to assess the diagnostic performance of the texture parameters.Results: In the periferal zone, 39 men had csPCa, while 41 had benign lesions or clinically insignificant prostate cancer (cisPCa). The majority of texture parameters showed statistically significant differences between the groups. Univariate ROC analysis showed that the ADC mean and ADC median were the best variables in differentiating csPCa (p < 0.001). The first-order logistic regression model (mean + entropy) based on the ADC maps had a higher AUC value (0.996; 95% CI: 0.989-1) than other texture-based logistic regres-sion models (p < 0.001).Conclusion: MRTA is useful in differentiating csPCa from other lesions in the PZ. Consequently, the first-order multivariate regression model based on ADC maps had the highest diagnostic performance in differentiating csPCa.