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Publication Metadata only A comparison of capillary and venous blood sampling methods for the use in haemorheology studies(Ios Press, 2011) Simmonds, Michael J.; Meiselman, Herbert J.; Marshall-Gradisnik, Sonya M.; N/A; Başkurt, Oğuz Kerim; Faculty Member; School of Medicine; N/AThere is accumulating evidence that exercise may improve disturbed haemorheological parameters that are typically observed in various chronic diseases, thus there is a growing interest in exploring the influence of various exercise models for the improvement of haemorheology. Blood sampling using venipuncture, however, can be limiting during exercise and/or in field settings. The purpose of the present study was to investigate whether venous and capillary blood samples yield comparable red blood cell (RBC) deformability and aggregation indices. Twelve healthy volunteers (6 males and 6 females; age 30 +/- 9 yrs; body mass index 24.9 +/- 2.8 kgm(-2)) provided blood samples that were collected simultaneously from: i) a prominent forearm vein by venipuncture; ii) the earlobe using a lancet; iii) the middle finger using a lancet. Haematocrit, RBC deformability (Rheoscan-D, Sewon Meditech Inc., Korea) and RBC aggregation (Myrenne GmbH, Roetgen, Germany) were measured for each sample. Haematocrit and RBC deformability were not different between the three sampling sites, and the group averages of RBC aggregation parameters were not different between the three sampling methods. The time course of RBC aggregation was slower when using blood sampled from the earlobe, and there was stronger agreement between RBC aggregation parameters measured using venous and capillary finger samples compared with venous and earlobe. It is suggested that capillary blood sampling from the finger may provide a reliable alternative to venous blood sampling in clinical and field settings.Publication Open Access A multi-center study on the efficacy of eltrombopag in management of refractory chronic immune thrombocytopenia: a real-life experience(Galenos Yayınevi, 2019) Çekdemir, Demet; Güvenç, Serkan; Özdemirkıran, Füsun; Eser, Ali; Toptaş, Tayfur; Özkocaman, Vildan; Haydaroğlu Şahin, Handan; Ermiş Turak, Esra; Esen, Ramazan; Cömert, Melda; Sadri, Sevil; Aslaner, Müzeyyen; Uncu Ulu, Bahar; Karakuş, Abdullah; Selim Bapur, Derya; Alacacıoğlu, İnci; Aydın, Demet; Tekinalp, Atakan; Namdaroğlu, Sinem; Ceran, Funda; Tarkun, Pınar; Kiper, Demet; Çetiner, Mustafa; Yenerel, Mustafa; Demir, Ahmet Muzaffer; Yılmaz, Güven; Terzi, Hatice; Atilla, Erden; Malkan, Ümit Yavuz; Acar, Kadir; Öztürk, Erman; Tombak, Anıl; Sunu, Cenk; Salim, Ozan; Alayvaz, Nevin; Sayan, Özkan; Ozan, Ülkü; Ayer, Mesut; Gökgöz, Zafer; Andıç, Neslihan; Kızılkılıç, Ebru; Noyan, Figen; Özen, Mehmet; Pepedil Tanrıkulu, Funda; Alanoğlu, Güçhan; Özkan, Hasan Atilla; Aslan, Vahap; Çetin, Güven; Akyol Erikçi, Alev; Deveci, Burak; Ersoy Dursun, Fadime; Dermenci, Hasan; Aytan, Pelin; Gündüz, Mehmet; Karakuş, Volkan; Özlü, Can; Demircioğlu, Sinan; Akay Yanar, Olga Meltem; Özatlı, Düzgün; Ündar, Levent; Tiftik, Eyüp Naci; Türköz Sucak, Ayhan Gülsan; Haznedaroğlu, İbrahim; Özcan, Muhit; Şencan, Mehmet; Tombuloğlu, Murat; Özet, Gülsüm; Bilgir, Oktay; Turgut, Burhan; Özcan, Mehmet Ali; Bahriye Payzın, Kadriye; Sönmez, Mehmet; Ayyıldız, Orhan; Dal, Mehmet Sinan; Ertop, Şehmus; Turgut, Mehmet; Soysal, Teoman; Kaya, Emin; Ünal, Ali; Pehlivan, Mustafa; Atagündüz, Işık; Tuğlular Fıratlı, Tülin; Saydam, Güray; Diz Küçükkaya, Reyhan; N/A; Çetiner, Mustafa; Öztürk, Erman; Faculty Member; Doctor; School of MedicineObjective: the aim of the present study was to evaluate the efficacy and safety of eltrombopag, an oral thrombopoietin receptor agonist, in patients with chronic immune thrombocytopenia (ITP). Materials and Methods: A total of 285 chronic ITP patients (187 women, 65.6%; 98 men, 34.4%) followed in 55 centers were enrolled in this retrospective cohort. Response to treatment was assessed according to platelet count (/mm3) and defined as complete (platelet count of >100,000/mm3), partial (30,000-100,000/mm3 or doubling of platelet count after treatment), or unresponsive (<30,000/mm3). Clinical findings, descriptive features, response to treatment, and side effects were recorded. Correlations between descriptive, clinical, and hematological parameters were analyzed. Results: The median age at diagnosis was 43.9±20.6 (range: 3-95) years and the duration of follow-up was 18.0±6.4 (range: 6-28.2) months. Overall response rate was 86.7% (n=247). Complete and partial responses were observed in 182 (63.8%) and 65 (22.8%) patients, respectively. Thirty-eight patients (13.4%) did not respond to eltrombopag treatment. For patients above 60 years old (n=68), overall response rate was 89.7% (n=61), and for those above 80 years old (n=12), overall response rate was 83% (n=10). Considering thrombocyte count before treatment, eltrombopag significantly increased platelet count at the 1st, 2nd, 3rd, 4th, and 8th weeks of treatment. As the time required for partial or complete response increased, response to treatment was significantly reduced. The time to reach the maximum platelet levels after treatment was quite variable (1-202 weeks). Notably, the higher the maximum platelet count after eltrombopag treatment, the more likely that side effects would occur. The most common side effects were headache (21.6%), weakness (13.7%), hepatotoxicity (11.8%), and thrombosis (5.9%). Conclusion: results of the current study imply that eltrombopag is an effective therapeutic option even in elderly patients with chronic ITP. However, patients must be closely monitored for response and side effects during treatment. Since both response and side effects may be variable throughout the follow-up period, patients should be evaluated dynamically, especially in terms of thrombotic risk factors. / Amaç: bu çalışmanın amacı kronik immün trombositopeni (ITP) hastalarında bir oral trombopoietin reseptör agonisti olan eltrombopagın etkinlik ve güvenirliliğini değerlendirmektir. Gereç ve Yöntemler: elli beş merkezde izlem altındaki toplam 285 kronik ITP hastası (187 kadın, %65,6) bu geriye dönük küme çalışmasına alınmıştır. Tedaviye yanıt trombosit sayısına göre değerlendirilmiş ve tam yanıt (>100.000/mm3), kısmi yanıt (30.000-100.000/mm3 veya tedaviden sonra trombosit sayısının bir kat artmış olması) ve yanıtsızlık (<30.000/mm3) olarak tanımlanmıştır. Hastaların klinik bulguları, tanımlayıcı özellikleri, tedaviye yanıt ve yan etki bilgileri toplanmış ve aralarındaki ilişki incelenmiştir. Bulgular: tanı anında yaş ortalaması 43,9±20,6 (3-95) yıl olan hastalar ortalama 18,0±6,4 (6-28,2) ay izlenmiştir. Tam ve kısmi yanıtı içeren toplam yanıt %86,7 (n=247) bulundu. Sırasıyla 182 (%63,8) ve 65 (%22,8) hastada tam ve parsiyel tedavi yanıtları gözlenmiştir. Otuz sekiz hasta (%13,4) eltrombopag tedavisine yanıt vermemiştir. Altmış yaş üzerindeki hastalarda (n=68) toplam yanıt %89,7 (n=61) bulunurken, bu oran 80 yaş üzerindeki (n=12) hastalarda %83 (n=10) olmuştur. Tedavi öncesi trombosit sayısı göz önüne alındığında, eltrombopag, tedavinin 1., 2., 3., 4. ve 8. haftalarında trombosit sayısını anlamlı şekilde artırmıştır. Kısmi veya tam cevap için gereken süre arttıkça, tedaviye cevap önemli ölçüde azaldığı saptanmıştır. Eltrombopag tedavisinden sonra maksimum trombosit sayısı ne kadar yüksekse, yan etkilerin oluşabilme ihtimalinin o kadar yüksek olabildiği dikkati çekmiştir. En sık görülen yan etkiler baş ağrısı (%21,6), güçsüzlük (%13,7) ve hepatotoksisite (%11,8) ve trombozdur (%5,9). Sonuç: Mevcut çalışmanın sonuçları, eltrombopag tedavisinin kronik ITP’de, yaşlı hastalar dahil olmak üzere, etkili bir tedavi seçeneği olduğunu göstermektedir. Bununla birlikte, hastalar tedavi sırasında yanıt ve yan etkiler açısından yakından izlenmelidir. Hem cevap hem de yan etkiler, takip süresi boyunca değişken olabileceğinden, hastalar özellikle tromboz risk faktörleri açısından dinamik olarak değerlendirilmelidir.Publication Metadata only Adult philadelphia chromosome-positive acute lymphoblastic leukemia in daily practice: a multicenter experience(Elsevier, 2016) Tekgunduz, Emre; Goker, Hakan; Kaynar, Leylagul; Sari, Ismail; Pala, Cigdem; Dogu, Mehmet Hilmi; Turgut, Burhan; Korkmaz, Serdal; Tetik, Aysegul; Buyukasik, Yahya; Hacioglu, Sibel Kabukcu; Bozdag, Sinem Civriz; Ozdemir, Evren; Altuntas, Fevzi; N/A; Öztürk, Erman; Doctor; N/A; Koç University Hospital; N/AIn this retrospective, multicenter study, we evaluated the real-life outcomes of adult Philadelphia-positive acute lymphoblastic leukemia patients. The best results in terms of survival are achieved in patients who were treated with tyrosine kinase inhibitors during induction and received allogeneic hematopoietic cell transplantation as part of consolidation. Background: The prognosis of Philadelphia-positive acute lymphoblastic leukemia (Ph+ ALL) is generally poor. Currently, allogeneic hematopoietic cell transplantation (allo-HCT) is the only accepted therapy with curative potential. Patients and Methods: Herein, we report our multicenter, retrospective experience with 46 (23 female; 23 male) Ph+ ALL patients, who were treated off-study between 2005 and 2012. Results: The median age of the patients was 46 years (range, 19-73 years). During induction, 30 (65%), 13 (28%), and 3 (7%) patients received tyrosine kinase inhibitors (TKIs) concurrent with chemotherapy (TKIs/chemotherapy), chemotherapy only, and TKIs only, respectively. Following induction, rates of complete remission (CR) of the study population were 85% (n = 39). CR rate in patients receiving TKIs during induction (n = 33) was significantly higher compared with patients who received chemotherapy only (n = 13; P = .011). Taking TKIs during induction significantly reduced induction mortality (3.3% vs. 38%; P = .01). Allo-HCT was performed subsequently in 21 (46%) patients. More patients who received TKIs with or without chemotherapy (19/33; 58%) during induction were able to undergo to allo-HCT compared with patients who received chemotherapy only (2/13; 15%; P = .005). Median overall survival of patients who were treated with TKIs during induction and received allo-HCT (not reached; NR) was significantly prolonged compared with patients who received allo-HCT but without TKIs during induction (23.2 months) and to the rest of the cohort (21.2 months; P = .019). Conclusions: Current state-of-the art management of Ph+ ALL in real-life seems to be incorporation of TKIs to chemotherapy regimens and proceeding to allo-HCT, whenever possible.Publication Metadata only An evaluation of thrombocytopenia cases in the hematology clinic of the ankara numune training and research hospital(Wolters Kluwer Medknow Publications, 2022) Sarı, Öznur; N/A; Üre, Ümit Barbaros; Doctor; N/A; Koç University Hospital; N/ABackground: Thrombocytopenia is a major disease that requires the referral of outpatient and hospitalized patients to hematology specialists. Objectives: The present study aims to evaluate the laboratory and transfusion statuses of adult patients admitted to our hospital and receiving outpatient/inpatient treatment and diagnosed with thrombocytopenia (< 100 x 109/l). Design: Single-center, retrospective, laboratory-based study. Patients and Methods: In the study, after obtaining permission of the hospital's Non-Invasive Clinical Research Ethics Committee, the information of patients diagnosed with thrombocytopenia (platelet count < 100 x 109/l) and who were examined and treated in the outpatient/inpatient settings between 2008 and 2010 were retrospectively analyzed using patient files and the hospital electronic database. Sample Size: A total of 1020 patients diagnosed with thrombocytopenia. Results: The patients were divided into groups according to the most common diagnoses for diseases associated with thrombocytopenia (hematological malignancy, disseminated intravascular coagulation (DIC)-sepsis, immune thrombocytopenia (ITP), infection, and chronic liver disease (n=708). Chemotherapy-induced, drug-induced, nutritional (B12, folate deficiency, etc.), OKIT, pregnancy-induced thrombocytopenias and other less common causes of thrombocytopenia were evaluated in a separate group (n=312). It was found that female patients were more frequently diagnosed with ITP (71.7 vs. 28.3%). Sex distributions were similar in other groups. The highest mean age (71 years: 50/80) was observed in patients with DIC-sepsis, whereas the lowest mean age was found in patients with ITP (40 years: 30/57) (P < 0.001). It was found that the most frequent need for transfusion developed in patients diagnosed with acute myeloid leukemia, acute lymphoblastic leukemia, and aplastic anemia. Conclusion: In this study, it was determined that the prevalence of thrombocytopenia was highest in patients diagnosed with hematological malignancy, ITP, and DIC-sepsis, respectively. In cases of hematological malignancy, the need for replacement of blood products is considered to be inevitable during the treatment process of the underlying disease compared with other clinical conditions.Publication Metadata only Applications of deep learning to the assessment of red blood cell deformability(IOS Press, 2021) Turgut, Alper; N/A; Yalçın, Özlem; Faculty Member; School of Medicine; 218440BACKGROUND: Measurement of abnormal Red Blood Cell (RBC) deformability is a main indicator of Sickle Cell Anemia (SCA) and requires standardized quantification methods. Ektacytometry is commonly used to estimate the fraction of Sickled Cells (SCs) by measuring the deformability of RBCs from laser diffraction patterns under varying shear stress. In addition to estimations from model comparisons, use of maximum Elongation Index differences (Delta EImax) at different laser intensity levels was recently proposed for the estimation of SC fractions. OBJECTIVE: Implement a convolutional neural network to accurately estimate rigid-cell fraction and RBC concentration from laser diffraction patterns without using a theoretical model and eliminating the ektacytometer dependency for deformability measurements. METHODS: RBCs were collected from control patients. Rigid-cell fraction experiments were performed using varying concentrations of glutaraldehyde. Serial dilutions were used for varying the concentration of RBC. A convolutional neural network was constructed using Python and TensorFlow. RESULTS and CONCLUSIONS: Measurements and model predictions show that a linear relationship between Delta EImax and rigid-cell fraction exists only for rigid-cell fractions less than 0.2. The proposed neural network architecture can be used successfully for both RBC concentration and rigid-cell fraction estimations without a need for a theoretical model.Publication Metadata only Azacitidine versus decitabine in patients with refractory anemia with excess blast-results of multicenter study(Elsevier, 2016) Salim, Ozan; Toptas, Tayfur; Avsar, Esin; Yucel, Orhan Kemal; Geduk, Ayfer; Mehtap, Ozgur; Tombak, Anil; Tiftik, Eyup Naci; Deveci, Burak; Kurtoglu, Erdal; Kara, Osman; Atagunduz, Isik Kaygusuz; Tuglular, Tulin Firatli; Undar, Levent; N/A; Öztürk, Erman; Ferhanoğlu, Ahmet Burhan; Doctor; Faculty Member; N/A; School of Medicine; Koç University Hospital, N/A; N/A; 18320The present study aimed to compare the efficacy and safety of azacitidine and decitabine in patients with myelodysplastic syndrome (MDS). A total of 88 patients diagnosed with refractory anemia with excess blast (RAEB) treated with azacitidine (n = 57) or decitabine (n = 31) were evaluated. Comparisons between azacitidine and decitabine groups were performed in the whole cohort, and in a 1:1 propensity score-matched cohort in order to reduce the simple selection bias. Patients who received azacitidine or decitabine had comparable overall response rates in both the unmatched (49.1% vs. 64.5%, p = 0.166) and the propensity-matched cohorts (52% vs. 68%, p = 0.248). The cumulative incidence of AML transformation at one year was comparable between azacitidine and decitabine in the unmatched (24.0% vs. 31.3%, p = 0.26) and in the propensity-matched cohorts (18.7% vs. 31.5%, p = 0.11). There was no difference in terms of transfusion requirement, febrile neutropenia episodes or the need for antifungal use during the treatment cycles in the propensity-matched cohort. The median overall survival was 20.4 months for azacitidine and 16.8 months for decitabine (p = 0.59). Finally, we found that at least a four-cycle treatment with any HMA was a favorable factor. In conclusion, both azacitidine and decitabine have similar efficacy and toxicity profiles in the treatment of MDS-RAEB.Publication Open Access Blood storage alters mechanical stress responses of erythrocytes(IOS Press, 2017) N/A; Uğurel, Elif; Küçüksümer, Zeynep; Eğlenen, Buse; Yalçın, Özlem; Researcher; Graduate School of Health Sciences; School of Medicine; N/A; N/A; N/A; 218440BACKGROUND: Erythrocytes undergo irreversible morphological and biochemical changes during storage. Reduced levels of deformability have been reported for stored erythrocytes. Erythrocyte deformability is essential for healthy microcirculation. OBJECTIVE: The aim of this study is to evaluate shear stress (SS) induced improvements of erythrocyte deformability in stored blood. METHODS: Deformability changes were evaluated by applying physiological levels of SS (5 and 10 Pa) in metabolically depleted blood for 48 hours and stored blood for 35 days with citrate phosphate dextrose adenine-1 (CPDA-1). Laser diffractometry was used to measure erythrocyte deformability before and after application of SS. RESULTS: Erythrocyte deformability, as a response to continuous SS, was significantly improved in metabolically depleted blood, whereas it was significantly impaired in the blood stored for 35 days with CPDA-1 (p <= 0.05). The SS-induced improvements of deformability were deteriorated due to storage and relatively impaired according to the storage time. However, deformability of stored blood after exposure to mechanical stress tends to increase at low levels of shear while decreasing at high SS levels. CONCLUSION: Impairment of erythrocyte deformability after storage may contribute to impairments in the recipient's microcirculation after blood transfusion. The period of the storage should be considered to prevent microcirculatory problems and insufficient oxygen delivery to the tissues.Publication Metadata only Cases of secondary hemophagocytic lymphohistiocytosis: a single center experience(Ferrata Storti Foundation, 2015) Karaman, S.; Yıldız, I.; Nişli, K.; Aktürk, H.; Çıtak, A.; Anak, S.; Ünüvar, A.; Öztürk, G.; Karakaş, Z.; Devecioğlu, O.; N/A; N/A; Demirkol, Demet; Bilge, İlmay; Faculty Member; Faculty Member; School of Medicine; School of Medicine; 108964; 198907N/APublication Open Access Cases of secondary hemophagocytic lymphohistiocytosis: a single center experience(Ferrata Storti Foundation, 2015) Karaman, Serap; Yıldız, İsmail; Nisli, Kemal; Aktürk, Hacer; Citak, Agop; Anak, Sema; Unuvar, Ayşegül; Öztürk, Gülyüz; Karakaş, Zeynep; Devecioğlu, Ömer; N/A; Demirkol, Demet; Bilge, İlmay; Faculty Member; Faculty Member; School of Medicine; N/A; 198907Publication Metadata only Central nervous system relapse in patients with primary mediastinal large b-cell lymphoma: incidence and risk factors in the Rituximab era(American Society of Hematology (ASH), 2022) Vassilakopoulos, Theodoros P.; Panitsas, Fotios; Mellios, Zois; Apostolidis, John; Piperidou, Alexia; Michael, Michalis D.; Gurion, Ronit; Hatzimichael, Eleftheria; Karakatsanis, Stamatis J.; Dimou, Maria; Kalpadakis, Christina; Katodritou, Eirini; Leonidopoulou, Theoni; Kotsianidis, Ioannis; Giatra, Chara; Kanellias, Nikolaos; Sayyed, Ayman; Tadmor, Tamar; Kaynar, Leylagul; Zektser, Miri; Symeonidis, Argiris; Verrou, Evgenia; Gutwein, Odit; Ganzel, Chezi; Karianakis, Giorgos; Isenberg, Jonathan; Gainaru, Gabriela; Triantafyllou, Theodora; Vrakidou, Efimia; Palassopoulou, Maria; Ozgur, Mehmet; Paydas, Semra; Tsirigotis, Panagiotis; Tsirogianni, Maria; Tuglular, Tulin; Chatzidimitriou, Chrysovalantou; Kotsopoulou, Maria; Terpos, Evangelos; Zikos, Panagiotis; Koumarianou, Argyro; Poziopoulos, Christos; Boutsis, Dimitrios; Gafter-Gvili, Anat; Karmiris, Themistoklis; Angelopoulou, Maria K.; Papaioannou, Maria Bakiri; Pangalis, Gerassimos; Panayiotidis, Panayiotis; Horowitz, Netanel A.; Papageorgiou, Sotirios; N/A; Ferhanoğlu, Ahmet Burhan; Akay, Olga Meltem; Atalar, Semra Cemre; Faculty Member; Faculty Member; Undergraduate Student; School of Medicine; School of Medicine; School of Medicine; 18320; 170966; N/AN/A