Browsing by Author "Kahraman, S"
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Item Determination of fracture depth of rock blocks from P-wave velocityKahraman, S; Soylemez, M; Fener, MThe quality of large rock blocks produced from quarries depends significantly on the fractures and the extent to which they penetrate into the rock. The paper reports a laboratory study to evaluate the possibility of the determining fracture depth in rock blocks from P-wave velocity. Three igneous, three sedimentary and three metamorphic rocks were studied. Inverse linear relations were found between the fracture depths and the P-wave velocities. Although, the slope of the regression lines is approximately the same for the rocks belonging to one rock class, different trends are seen for the different rock types. In addition, some correlation was found between the slopes of the regression lines and the physical properties of the rocks.Item Effects of thermal oxidation temperature on vacuum evaporated tin dioxide filmÇakmak, HM; Çetinkara, HA; Kahraman, S; Bayansal, F; Tepe, M; Güder, HS; Çipiloglu, MAIn order to investigate the effect of thermal oxidation temperature on tin dioxide (SnO2), tin dioxide films were obtained on quartz substrates by vacuum evaporation of tin metal. The films were characterized by X-ray diffraction (XRD) analyses, scanning electron microscopy (SEM), temperature dependent electrical resistivity measurement and optical absorption spectroscopy. The SEM images showed that the films are dense, continuous and are composed of nanoparticles and particle sizes are increased after thermal oxidation. From the X-ray measurement results, the films indicated two strong reflection peaks of tetragonal structure in the orientations of (101) and (200) at 20 = 33.8 degrees and 37.95 degrees, respectively. Intensity of the peaks increased with increasing thermal oxidation temperature. We found resistivity values of about 10(-4) Omega-cm. Optical absorption spectra of the films in the UV-Vis spectral range revealed that optical band gap (E-g) value of the films increases with increasing thermal oxidation temperature. (C) 2012 Elsevier Ltd. All rights reserved.Item Effects of Perceived Parental Attitudes on Children's Views of SmokingÖztürk, C; Kahraman, S; Bektas, MBackground: The aim of this study was to examine the effects of perceived parental attitudes on children's discernment of cigarettes. Materials and Methods: The study sample consisted of 250 children attending grades 6, 7 and 8. Data were collected via a socio-demographic survey questionnaire, the Parental Attitude Scale (PAS) and the Decisional Balance Scale (DBS). Data analysis covered percentages, medians, one-way analysis of variance (ANOVA) and post-hoc tests using a statistical package. Results: There were 250 participants; 117 were male, 133 were female. The mean age was 13.1 +/- 0.98 for the females and 13.3 +/- 0.88 for the males. A statistically significant difference was found in the children's mean scores for 'pros' subscale on the Decisional Balance Scale (DBS) according to perceived parental attitudes (F=3.172, p=0.025). There were no statistically significant differences in the DBS 'cons' subscale scores by perceived parental attitudes. Conclusions: It was determined that while perceived parental attitudes affect children's views on advantages of smoking, they have no effect on children's views on its disadvantages.Item A Non-pharmacological Application to Reduce Neonatal Pain During Lumbar Puncture Procedure in Neonatal Intensive Care: Placing a Pillow on the AbdomenTanriverdi, S; Yaman, HK; Kahraman, S; Kublay, EAim: Lumbar puncture is one of the most common painful procedures which newborn babies encounter during neonatal intensive care followup. It is important to control pain duringthis procedure. The aim of this studywas to showthe effects of using a pillow placed in the abdominal area as a non-pharmacological application in order to relieve neonatal pain during the lumbar puncture procedure. Materialsand Methods: Forty newborn babies who were monitored in the neonatal intensive care unit ofour hospital and received an indication for lumbar puncture were included in this study. Babies who underwent lumbar puncture were randomly selected and divided into two groups. Lumbar puncture was performed on 20 babies in group 1 by placing a pillow which we had prepared in the abdominal area. In addition, lumbar puncture was performed on 20 babies in group 2 without placing a pillow in the abdominal area during lumbar puncture. The vital signs and the neonatal infants pain scale pain scores of the two groups were compared. Results: Forty newborn babies were included in this study. Their average week of birth was 30.61 +/- 4.32 (24-38) weeks and their average birth weight was 1.531.25 +/- 951.34 (640-3.675) grams. Of the babies, 26 (65%) were male and 14 (35%) were female. When the pillow we prepared was placed on the abdominal area during lumbar puncture, the pain score was lower, although this difference was not significant. Conclusion: Placing a pillow on the abdominal area during lumbar puncture, which is one of the painful procedures in neonatal intensive care, can be applied as a nonpharmacological method.Item Efficacy of subsequent treatments in patients with hormone-positive advanced breast cancer who had disease progression under CDK 4/6 inhibitor therapy (vol 23, 136, 2023)Karacin, C; Oksuzoglu, B; Demirci, A; Keskinkiliç, M; Baytemür, NK; Yilmaz, F; Selvi, O; Erdem, D; Avsar, E; Paksoy, N; Demir, N; Göksu, SS; Türker, S; Bayram, E; Çelebi, A; Yilmaz, H; Kuzu, ÖF; Kahraman, S; Gökmen, I; Sakin, A; Alkan, A; Nayir, E; Ugrakli, M; Acar, Ö; Ertürk, I; Demir, H; Aslan, F; Sönmez, Ö; Korkmaz, T; Celayir, ÖM; Karadag, I; Kayikçioglu, E; Sakalar, T; Öktem, IN; Eren, T; Erul, E; Mocan, EE; Kalkan, Z; Yildirim, N; Ergün, Y; Akagündüz, B; Karakaya, S; Kut, E; Teker, F; Demirel, BÇ; Karaboyun, K; Almuradova, E; Ünal, OÜ; Oyman, A; Isik, D; Okutur, K; Öztosun, B; Gülbagci, BB; Kalender, ME; Sahin, E; Seyyar, M; Özdemir, Ö; Selçukbiricik, F; Kanitez, M; Dede, I; Gümüs, M; Gökmen, E; Yaren, A; Menekse, S; Ebinç, S; Aksoy, S; Imamoglu, GI; Altinbas, M; Çetin, B; Uluç, BO; Er, Ö; Karadurmus, N; Erdogan, AP; Artaç, M; Tanriverdi, Ö; Çiçin, I; Sendur, MAN; Oktay, E; Bayoglu, IV; Paydas, S; Aydiner, A; Salim, DK; Geredeli, Ç; Yavuzsen, T; Dogan, M; Hacibekiroglu, IItem Efficacy of subsequent treatments in patients with hormone-positive advanced breast cancer who had disease progression under CDK 4/6 inhibitor therapyKaracin, C; Oksuzoglu, B; Demirci, A; Keskinkiliç, M; Baytemür, NK; Yilmaz, F; Selvi, O; Erdem, D; Avsar, E; Paksoy, N; Demir, N; Göksu, SS; Türker, S; Bayram, E; Çelebi, A; Yilmaz, H; Kuzu, ÖF; Kahraman, S; Gökmen, I; Sakin, A; Alkan, A; Nayir, E; Ugrakli, M; Acar, Ö; Ertürk, I; Demir, H; Aslan, F; Sönmez, Ö; Korkmaz, T; Celayir, ÖM; Karadag, I; Kayikçioglu, E; Sakalar, T; Öktem, IN; Eren, T; Urul, E; Mocan, EE; Kalkan, Z; Yildirim, N; Ergün, Y; Akagündüz, B; Karakaya, S; Kut, E; Teker, F; Demirel, BÇ; Karaboyun, K; Almuradova, E; Ünal, OÜ; Oyman, A; Isik, D; Okutur, K; Öztosun, B; Gülbagci, BB; Kalender, ME; Sahin, E; Seyyar, M; Özdemir, Ö; Selçukbiricik, F; Kanitez, M; Dede, I; Gümüs, M; Gökmen, E; Yaren, A; Menekse, S; Ebinç, S; Aksoy, S; Imamoglu, GI; Altinbas, M; Çetin, B; Uluç, BO; Er, Ö; Karadurmus, N; Erdogan, AP; Artaç, M; Tanriverdi, Ö; Çiçin, I; Sendur, MAN; Oktay, E; Bayoglu, IV; Paydas, S; Aydiner, A; Salim, DK; Geredeli, Ç; Yavuzsen, T; Dogan, M; Hacibekiroglu, IBackground There is no standard treatment recommended at category 1 level in international guidelines for subsequent therapy after cyclin-dependent kinase 4/6 inhibitor (CDK4/6) based therapy. We aimed to evaluate which subsequent treatment oncologists prefer in patients with disease progression under CDKi. In addition, we aimed to show the effectiveness of systemic treatments after CDKi and whether there is a survival difference between hormonal treatments (monotherapy vs. mTOR-based). Methods A total of 609 patients from 53 centers were included in the study. Progression-free-survivals (PFS) of subsequent treatments (chemotherapy (CT, n:434) or endocrine therapy (ET, n:175)) after CDKi were calculated. Patients were evaluated in three groups as those who received CDKi in first-line (group A, n:202), second-line (group B, n: 153) and >= 3rd-line (group C, n: 254). PFS was compared according to the use of ET and CT. In addition, ET was compared as monotherapy versus everolimus-based combination therapy. Results The median duration of CDKi in the ET arms of Group A, B, and C was 17.0, 11.0, and 8.5 months in respectively; it was 9.0, 7.0, and 5.0 months in the CT arm. Median PFS after CDKi was 9.5 (5.0-14.0) months in the ET arm of group A, and 5.3 (3.9-6.8) months in the CT arm (p = 0.073). It was 6.7 (5.8-7.7) months in the ET arm of group B, and 5.7 (4.6-6.7) months in the CT arm (p = 0.311). It was 5.3 (2.5-8.0) months in the ET arm of group C and 4.0 (3.5-4.6) months in the CT arm (p = 0.434). Patients who received ET after CDKi were compared as those who received everolimus-based combination therapy versus those who received monotherapy ET: the median PFS in group A, B, and C was 11.0 vs. 5.9 (p = 0.047), 6.7 vs. 5.0 (p = 0.164), 6.7 vs. 3.9 (p = 0.763) months. Conclusion Physicians preferred CT rather than ET in patients with early progression under CDKi. It has been shown that subsequent ET after CDKi can be as effective as CT. It was also observed that better PFS could be achieved with the subsequent everolimus-based treatments after first-line CDKi compared to monotherapy ET.Item Clinical outcomes of cyclin-dependent kinase 4-6 (CDK 4-6) inhibitors in patients with male breast cancer: A multicenter studyYildirim, HC; Mutlu, E; Chalabiyev, E; Özen, M; Keskinkiliç, M; Ön, S; Çelebi, A; Dursun, B; Acar, O; Kahraman, S; Aykan, MB; Kaman, O; Dogan, A; Erdogan, AP; Celayir, OM; Günenç, D; Güven, DC; Bayoglu, IV; Yavuzsen, T; Hacibekiroglu, I; Inanç, M; Kiliçkap, S; Yalçin, S; Aksoy, SBackground: Since breast cancer is less common in men than in women, data on the use of new therapeutic agents, including cyclin-dependent kinase 4-6 (CDK 4-6) inhibitors, are limited in patients with metastatic hormone receptor positive (HR+), human epidermal growth factor receptor 2-negative (HER2-) male breast cancer. Therefore; we aimed to investigate the treatment responses of metastatic HR+, HER2-male breast cancer patients treated with CDK 4-6 inhibitors in a multicenter real-life cohort. Methods: Male patients with a diagnosis of HR+ and HER2-metastatic breast cancer, treated with any CDK 4-6 inhibitor, were included in the study. Demographic and clinical characteristics of the patients were recorded. We aimed to determine progression-free survival (PFS) time, response rates and drug related side effects. Results: A total 25 patients from 14 institutions were recruited. The mean age at diagnosis was 57 years. Median follow-up was 19.53 (95% CI: 14.04-25.02) months. The overall response rate was 60%. While the median PFS was 20.6 months in the whole cohort, it wasn't reached in those using CDK 4-6 inhibitors in first line and 10 months in the subsequent lines (p:0.009). No new adverse events were encountered. Conclusion: In our study, we found that CDK 4-6 inhibitors are effective and safe options in men with HR+ and HER2-metastatic breast cancer as in women. Our results support the use of CDK 4-6 inhibitor-based combinations in the first-line treatment of HR+ and HER2-metastatic male breast cancer.Item A nationwide multicentre study in Turkey for establishing reference intervals of haematological parameters with novel use of a panel of whole bloodOzarda, Y; Ichihara, K; Bakan, E; Polat, H; Ozturk, N; Baygutalp, NK; Taneli, F; Guvenc, Y; Ormen, M; Erbayraktar, Z; Aksoy, N; Sezen, H; Demir, M; Eskandari, G; Polat, G; Mete, N; Yuksel, H; Vatansev, H; Gun, F; Akin, O; Ceylan, O; Noyan, T; Gozlukaya, O; Aliyazicioglu, Y; Kahraman, S; Dirican, M; Tuncer, GO; Kimura, S; Eker, PIntroduction: A nationwide multicentre study was conducted to establish well-defined reference intervals (Rls) of haematological parameters for the Turkish population in consideration of sources of variation in reference values (RVs). Materials and methods: K2-EDTA whole blood samples (total of 3363) were collected from 12 laboratories. Sera were also collected for measurements of iron, UIBC, TIBC, and ferritin for use in the latent abnormal values exclusion (LAVE) method. The blood samples were analysed within 2 hours in each laboratory using Cell Dyn and Ruby (Abbott), LH780 (Beckman Coulter), or XT-2000i (Sysmex). A panel of freshly prepared blood from 40 healthy volunteers was measured in common to assess any analyser-dependent bias in the measurements. The SD ratio (SDR) based on ANOVA was used to judge the need for partitioning RVs. Rls were computed by the parametric method with/without applying the LAVE method. Results: Analyser-dependent bias was found for basophils (Bas), MCHC, RDW and MPV from the panel test results and thus those Rls were derived for each manufacturer. Rls were determined from all volunteers' results for WBC, neutrophils, lymphocytes, monocytes, eosinophils, MCV, MCH and platelets. Gender-specific Rls were required for RBC, haemoglobin, haematocrit, iron, UIBC and ferritin. Region-specific Rls were required for RBC, haemoglobin, haematocrit, UIBC, and TIBC. Conclusions: With the novel use of a freshly prepared blood panel, manufacturer-specific Rls' were derived for Bas, Bas%, MCHC, RDW and MPV. Regional differences in Rls were observed among the 7 regions of Turkey, which may be attributed to nutritional or environmental factors, including altitude.Item The real-world outcomes of Lutetium-177 PSMA-617 radioligand therapy in metastatic castration-resistant prostate cancer: Turkish Oncology Group multicenter studyAlmuradova, E; Seyyar, M; Arak, H; Tamer, F; Kefeli, U; Koca, S; Sen, E; Telli, TA; Karatas, F; Gokmen, I; Turhal, NS; Sakalar, T; Ayhan, M; Ekinci, F; Hafizoglu, E; Kahraman, S; Kesen, O; Unal, C; Alan, O; Celik, S; Yekeduz, E; Omur, O; Gokmen, EMetastatic castration-resistant prostate cancer (mCRPC) remains a challenging condition to treat despite recent advancements. This retrospective study aimed to assess the activity and tolerability of Lutetium-177 (Lu-177) PSMA-617 radioligand therapy (RLT) in mCRPC patients across multiple cancer centers in Turkey. The study included 165 patients who received at least one cycle of Lu-177 PSMA-617 RLT, with the majority having bone metastases and undergone prior treatments. Prostate-specific antigen (PSA) levels were assessed before each treatment cycle, and the biochemical response was evaluated in accordance with the Prostate Cancer Work Group 3 Criteria. The PSA decline of >= 50% was classified as a response, while an increase of >= 25% in PSA levels was indicative of progressive disease. Neither response nor progression was considered as stable disease. The Lu-177 PSMA-617 RLT led to a significant PSA response, with 50.6% of patients achieving a >50% decrease in PSA levels. Median overall survival (OS) and progression-free survival were 13.5 and 8.2 months, respectively. Patients receiving Lu-177 PSMA-617 RLT in combination with androgen receptor pathway inhibitors (ARPIs) had a higher OS compared to those receiving Lu-177 PSMA-617 RLT alone (18.2 vs 12.3 months, P = .265). The treatment was generally well-tolerated, with manageable side effects such as anemia and thrombocytopenia. This study provides real-world evidence supporting the effectiveness and safety of Lu-177 PSMA-617 RLT in mCRPC patients, particularly when used in combination with ARPIs. These findings contribute to the growing body of evidence on the potential benefits of PSMA-targeted therapies in advanced prostate cancer.Item Efficacy and safety of folfiri plus aflibercept in second-line treatment of metastatic colorectal cancer: Real-life data from Turkish oncology groupErol, C; Sendur, MAN; Bilgetekin, I; Garbioglu, DB; Hamdard, J; Akbas, S; Hizal, M; Arslan, C; Sevinc, A; Kucukarda, A; Erdem, D; Kahraman, S; Cakir, E; Demirkiran, A; On, S; Dogan, I; Erdogan, AP; Koca, S; Kubilay, P; Eren, OO; Cilbir, E; Celik, E; Araz, M; Ozyukseler, DT; Yildirim, ME; Bahceci, A; Taskaynatan, H; Oyman, A; Deniz, GI; Menekse, S; Kut, E; Gulmez, A; Sakin, A; Nayir, E; Acar, R; Sen, E; Inal, A; Turhal, S; Kaya, AO; Paydas, S; Tastekin, D; Hacibekiroglu, I; Cincin, I; Bilici, A; Mandel, NM; Dede, DS; Akinci, MB; Oksuzoglu, B; Uncu, D; Yalcin, B; Artac, MAims: The addition of aflibercept to the fluorouracil and irinotecan (FOLFIRI) regimen significantly improved clinical outcomes in patients with metastatic colorectal cancer (CRC) previously treated with oxaliplatin. We aimed to investigate the efficacy and safety of second-line FOLFIRI and aflibercept combination in patients with metastatic CRC in real-life experience. Materials and Methods: Four hundred and thirty-three patients who treated with FOLFIRI and aflibercept in the second-line were included in the study. The clinical and pathological features of the patients were recorded retrospectively. Survival (overall and progression-free survival [PFS]), response rates, and safety data were analyzed. Results: The median age was 61. Majority of patients (87.5%) received first-line bevacizumab and 10.1% of patients received anti-epidermal growth factor receptor agents. About 80% of patients had KRAS, 18.6% of patients had NRAS, and 6.4% of patients had BRAF mutations. The median OS was 11.6 months (95% confidence interval [CI], 10.6-12.6) and the median PFS was 6 months (95% CI, 5.5-6.5). About 4.6% of patients had complete response and 30.6% of patients had partial response as best tumor response. Grade 1-2 toxicities were seen in 33.4% of patients, while grade 3-4 toxicities were recorded in 27% of patients. Eight patients (2%) died due to treatment toxicity. Conclusions: Overall and PFS were similar in routine clinical practice compared to phase III pivotal VELOUR trial. However, response rates were found to be higher. It was observed that there were fewer adverse events compared to the VELOUR trial.Item Activity of CDK4/6 inhibitors and parameters affecting survival in elderly patients in age-subgroups: Turkish Oncology Group (TOG) retrospective studyKahraman, S; Hizal, M; Demirel, BC; Guven, DC; Gumusay, O; Uluc, BO; Bayram, E; Gulbagci, B; Yasar, A; Davarci, SE; Mocan, EE; Acar, O; Isik, D; Aydin, E; Karakas, Y; Ozcelik, M; Keser, M; Okutur, SK; Eren, O; Menekse, S; Aydin, D; Yilmaz, F; Dogan, O; Ozkanli, G; Yucel, H; Sunar, V; Aykan, MB; Ozdemir, O; Duman, BB; Keskinkilic, M; Sakalar, T; Inal, A; Karaoglanoglu, M; Aksoy, A; Er, MM; Turhal, NS; Kalkan, NO; Sendur, MANHighly selective inhibitors of cyclin-dependent kinase 4 and 6 (CDK4/6is) have emerged as a standart of care for first- and second-line therapies in combination with endocrine therapy (ET) for HR+/HER2- metastatic breast cancer (MBC) patients. It has been reported that combination therapy is more effective than ET alone and is safe in elderly patients as well as young patients. Nevertheless, elderly and very old patients with HR+/HER2-MBC treated with CDK4/6 inhibitor (CDK4/6i) combinations are relatively underrepresented in randomized controlled trials. To contribute to the literature, we investigated the real-world efficacy, factors associated with survival and the rates of adverse events (AEs) of the treatment with palbociclib or ribociclib plus ET in the HR+/HER2- MBC patient cohort over the age of 65 for age subgroups. In this retrospective study, 348 patients were divided into subgroups: 65-69 years old, 70-79 years old and 80 years and older. Median PFS (mPFS) for whole group was 18.3 (95% CI,14.3-22.3) months. There was no significant difference in mPFS between age groups (p = 0.75). The estimated median OS (mOS) was 39.5 (95% CI, 24.9-54.1) months and there was no significant difference between age groups (p = 0.15). There was a meaningfull numerical difference that did not reach statistical significance in patients who received CDK4/6i treatment as the first line for MBC. Grade 3-4 AEs were reported in 42.7% for the entire group, and neutropenia was the most common (37.3%). It can be concluded that combination therapy with palbociclib or ribociclib with an ET partner has similar efficacy and is safe among subgroups of older patients diagnosed with HR+/HER2-MBC.