PubMed İndeksli Yayınlar Koleksiyonu
Permanent URI for this collectionhttps://hdl.handle.net/11727/4810
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Item Therapeutic Potential of Apigenin, a Plant Flavonoid, for Imatinib-Sensitive and Resistant Chronic Myeloid Leukemia Cells(2014) Solmaz, Soner; Gokbulut, Aysun Adan; Cincin, Birsu; Ozdogu, Hakan; Boga, Can; Cakmakoglu, Bedia; Kozanoglu, Ilknur; Baran, YusufDespite the presence of many therapeutic regimens like imatinib and other tyrosine kinase inhibitors, the development of resistance, intolerance, and side effects makes chronic myeloid leukemia (CML) therapy challenging. Thus, there is a need to discover novel drugs for CML patients. In this study, we attempted to assess apigenin, a common plant dietary flavonoid, in terms of its cytotoxic, apoptotic, and cytostatic effects on imatinib-sensitive and resistant Philadelphia-positive CML cells. We analyzed apigenin's effects on cell proliferation, apoptosis, caspase-3 activity, loss of mitochondrial membrane potential, and cell cycle progression in K562 and K562/IMA3 cells. Furthermore, we described genes and gene networks that are modulated in CML in response to apigenin. Results of our study revealed that apigenin has cytotoxic and apoptotic effects on both cell types. We also displayed that apigenin induced G2/M arrest in K562 cells while arresting K562/IMA3 cells in S phase especially at the highest apigenin concentration. The expression analysis identified a set of genes that were regulated by apigenin in K652 and K562/IMA3 cells. Association of modulated genes with biological functional groups identified several networks affected by apigenin including cell survival, proliferation, cell death, cell cycle, and cell signalling pathways.Item Use of Mesenchymal Cells to Modulate Immune Suppression and Immune Reconstruction in a Patient with Aplastic Anemia Complicated by Invasive Sino-Orbital Aspergillosis(2014) Ozdogu, Hakan; Yeral, Mahmut; Boga, Can; Kozanoglu, IlknurCultured human bone marrow mesenchymal cells (MSCs) have immunomodulatory and tissue regenerative properties. This report summarizes the result of post-transplant treatment with MSCs of a 26-year-old patient with aplastic anemia complicated by invasive sino-orbital aspergillosis. The patient was treated with MSCs to benefit from the dual effects of MSCs in immune reconstitution: suppression against alloreactive T cells and facilitation of the re-engraftment process. The patient did not develop acute or chronic graft-versus-host disease. The aspergillus infection healed completely. The engraftment failure was also ended without any complications. During his last visit in his fourth year after transplantation, the patient was in hematological remission. Human bone marrow-derived MSCs seem to have an important role in preventing or overcoming immunological complications in patients who undergo stem cell transplantation.Item Tunnelled Central Venous Catheter-Related Problems in the Early Phase of Haematopoietic Stem Cell Transplantation and Effects on Transplant Outcome(2015) Yeral, Mahmut; Boga, Can; Oguzkurt, Levent; Aliskan, Hikmet Eda; Ozdogu, Hakan; Demiroglu, Yusuf Ziya; 25805675Objective: Haematopoietic stem cell recipients need central venous catheters (CVCs) for easy administration of intravenous fluid, medications, apheresis, or dialysis procedures. However, CVCs may lead to infectious or non-infectious complications such as thrombosis. The effect of these complications on transplantation outcome is not clear. This manuscript presents the complication rates of double-lumen tunnelled CVCs and their effect on transplantation outcome. Materials and Methods: Data from 111 consecutive patients, of whom 75 received autologous and 36 received allogeneic peripheral blood stem cell transplantations, were collected retrospectively. The data were validated by the Record Inspection Group of the related JACIE-accredited transplantation centre. Results: Thrombosis developed in 2.7% of recipients (0.9 per 1000 catheter days). Catheter-related infection was identified in 14 (12.6%) patients (3.6 per 1000 catheter days). Coagulase-negative Staphylococcus was the most common causative agent. Engraftment time, rate of 100-day mortality, and development of grade II-IV graft-versus-host disease were not found to be associated with catheter-related complications. Conclusion: These results indicate that adverse events related with tunnelled CVCs are manageable and have no negative effects on transplant outcome.Item Cobalamin Deficiency Can Mask Depleted Body Iron Reserves(2015) Solmaz, Soner; Ozdogu, Hakan; Boga, Can; 25825568Vitamin B12 deficiency impairs DNA synthesis and causes erythroblast apoptosis, resulting in anaemia from ineffective erythropoiesis. Iron and cobalamin deficiency are found together in patients for various reasons. We have observed that cobalamin deficiency masks iron deficiency in some patients. We hypothesised that iron is not used by erythroblasts because of ineffective erythropoiesis due to cobalamin deficiency. Therefore, we aimed to demonstrate that depleted iron body reserves are masked by cobalamin deficiency. Seventy-five patients who were diagnosed with cobalamin deficiency were enrolled in this study. Complete blood counts and serum levels of iron, unsaturated iron binding capacity (UIBC), ferritin, vitamin B-12, and thyroid stimulant hormone were determined at diagnosis and after cobalamin therapy. Patients who had a combined deficiency at diagnosis and after cobalamin therapy were recorded. Before cobalamin therapy, we found increased serum iron levels (126.4 +/- A 63.4 A mu g/dL), decreased serum UIBC levels (143.7 +/- A 70.8 A mu g/dL), increased serum ferritin levels (192.5 +/- A 116.4 ng/mL), and increased transferrin saturation values (47.2 +/- A 23.5 %). After cobalamin therapy, serum iron levels (59.1 +/- A 30 A mu g/dL), serum ferritin levels (44.9 +/- A 38.9 ng/mL) and transferrin saturation values (17.5 +/- A 9.6 %) decreased, and serum UIBC levels (295.9 +/- A 80.6 A mu g/dL) increased. Significant differences were observed in all values (p < 0.0001). Seven patients (9.3 %) had iron deficiency before cobalamin therapy, 37 (49.3 %) had iron deficiency after cobalamin therapy, and a significant difference was detected between the proportions of patients who had iron deficiency (p < 0.0001). This study is important because insufficient data are available on this condition. Our results indicate that iron deficiency is common in patients with cobalamin deficiency, and that cobalamin deficiency can mask iron deficiency. Therefore, we suggest that all patients diagnosed with cobalamin deficiency should be screened for iron deficiency, particularly after cobalamin therapy.Item Hematopoietic Stem Cell Transplantation in Adult Sickle Cell Disease: Problems and Solutions(2015) Ozdogdu, Halkan; Boga, Can; 25912490Sickle cell disease-related organ injuries cannot be prevented despite hydroxyurea use, infection prophylaxis, and supportive therapies. As a consequence, disease-related mortality reaches 14% in adolescents and young adults. Hematopoietic stem cell transplantation is a unique curative therapeutic approach for sickle cell disease. Myeloablative allogeneic hematopoietic stem cell transplantation is curative for children with sickle cell disease. Current data indicate that long-term disease-free survival is about 90% and overall survival about 95% after transplantation. However, it is toxic in adults due to organ injuries. In addition, this curative treatment approach has several limitations, such as difficulties to find donors, transplant-related mortality, graft loss, graft-versus-host disease (GVHD), and infertility. Engraftment effectivity and toxicity for transplantations performed with nonmyeloablative reduced-intensity regimens in adults are being investigated in phase 1/2 trials at many centers. Preliminary data indicate that GVHD could be prevented with transplantations performed using reduced-intensity regimens. It is necessary to develop novel regimens to prevent graft loss and reduce the risk of GVHD.Item A Rare Complication Developing After Hematopoietic Stem Cell Transplantation: Wernicke's Encephalopathy(2015) Solmaz, Soner; Gereklioglu, Cigdem; Tan, Meliha; Demir, Senay; Yeral, Mahmut; Korur, Asli; Boga, Can; Ozdogu, Hakan; 25912759Thiamine is a water-soluble vitamin. Thiamine deficiency can present as a central nervous system disorder known as Wernicke's encephalopathy, which classically manifests as confusion, ataxia, and ophthalmoplegia. Wernicke's encephalopathy has rarely been reported following hematopoietic stem cell transplantation. Herein, we report Wernicke's encephalopathy in a patient with acute myeloid leukemia who had been receiving prolonged total parenteral nutrition after haploidentical allogeneic hematopoietic stem cell transplantation. To the best of our knowledge, this is the first case reported from Turkey in the literature.Item Recommendations for Risk Categorization and Prophylaxis of Invasive Fungal Diseases in Hematological Malignancies: A Critical Review of Evidence and Expert Opinion (TEO-4)(2015) Boga, Can; Bolaman, Zahit; Cagirgan, Seckin; Karadogan, Ihsan; Ozcan, Mehmet Ali; Ozkalemkas, Fahir; Saba, Rabin; Sonmez, Mehmet; Senol, Esin; Akan, Hamdi; Akova, Murat; 26316478This is the last of a series of articles on invasive fungal infections prepared by opinion leaders in Turkey. The aim of these articles is to guide clinicians in managing invasive fungal diseases in hematological malignancies and stem cell transplantation based on the available best evidence in this field. The previous articles summarized the diagnosis and treatment of invasive fungal disease and this article aims to explain the risk categorization and guide the antifungal prophylaxis in invasive fungal disease.Item Effect of Hereditary Hemochromatosis Gene H63D and C282Y Mutations on Iron Overload in Sickle Cell Disease Patients(2016) Terzi, Yunus Kasim; Balci, Tugce Bulakbasi; Boga, Can; Koc, Zafer; Celik, Zerrin Yilmaz; Ozdogu, Hakan; Karakus, Sema; Sahin, Feride Iffet; 27095682Objective: Hemochromatosis is an autosomal recessive disease that is one of the most important reasons for iron overload. Sickle cell disease is a hemoglobinopathy that occurs as a result of a homozygous mutation in the hemoglobin gene. Erythrocyte transfusion is frequently used in the treatment of this disease. Iron overload as a result of transfusion is important in the mortality and morbidity of sickle cell anemia patients as well as in other hemoglobinopathies. In this study, the effect of hemochromatosis gene (HFE) p.H63D and p.C282Y mutations on transfusion-related cardiac and liver iron overload in sickle cell disease patients who carry homozygous hemoglobin S mutation has been investigated. Materials and Methods: This is a prospective single-center cross-sectional study in patients with homozygous hemoglobin S mutation between the years 2008 and 2013. The patients were divided into two groups. The first group (group A, n=31) was receiving chelation therapy and the second group (group B, n=13) was not. Direct and indirect iron loads were analyzed by magnetic resonance imaging and biochemically, respectively. HFE gene mutations were analyzed by polymerase chain reaction-restriction fragment length polymorphism method. Statistical analyses were performed by independent samples t-test. Results: p.H63D mutation was detected in 10 (32.3%) patients in group A and in only 1 patient (7.7%) in group B. When the 2 groups were compared for iron overload, iron deposition in the liver was significantly higher in group B (p=0.046). In addition, in group A, iron deposition was significantly higher in HFE mutation carriers compared to patients without the mutation (p=0.05). Conclusion: Results of this study showed that HFE gene mutations are important in iron deposition in the liver in patients with sickle cell disease.Item Anorectal Complications During Neutropenic Period in Patients with Hematologic Diseases(2016) Solmaz, Soner; Korur, Asli; Gereklioglu, Cigdem; Asma, Suheyl; Buyukkurt, Nurhilal; Kasar, Mutlu; Yeral, Mahmut; Kozanoglu, Ilknur; Boga, Can; Ozdogu, Hakan; 26977278Background: Neutropenic patients are susceptible to any anorectal disease, and symptomatic anorectal disease afflicts 2-32% of oncology patients. Perianal infections are the most feared complication, considering the lack of natural defense against infectious microorganisms. When septic complications develop, the anorectal disease is potentially fatal, especially in neutropenic patients in whom mortality rates range between 11-57%. Although anorectal diseases are a frequent complication with potentially fatal outcomes among patients with hematologic diseases, sufficient data are not available in the literature. In this study, we aimed to investigate the anorectal complications developing during the neutropenic period in patients with hematologic diseases. Methods: A total of 79 patients whose neutropenic period (absolute neutrophil count < 500/mcL) continued for 7 days, or longer were included in the study. Results: A total of 34 patients out of 79 (43%) were detected to develop anorectal complications, of them 6 (7.6%) developed an anorectal infection. The patients were characterized according to the hematological disease and its status (active or not), the type of treatment and the presence of a history of an anorectal pathology before the onset of the hematologic disease. Nineteen (24.1%) patients had the history of anorectal disturbances before diagnosis of the hematologic disease, and recurrence of an anorectal pathology was found in 14 out of 19 patients(73.7%). In addition, the overall mortality rate was higher among the patients who developed anorectal complications compared to another group (41.2% vs. 22.2%, p= 0.059). Conclusion: Anorectal pathology is a common complication with high recurrence rate in neutropenic patients. Perianal infections are important as they can cause life-threatening outcomes although they are relatively rare among all anorectal complications. Therefore perianal signs and symptoms should be meticulously evaluated concerning early diagnosis and treatment.Item Development of Acute Promyelocytic Leukemia in a Patient With Gouty Arthritis on Long Term Colchicine(2016) Buyukkurt, Nurhilal; Korur, Asli; Boga, Can; 27408362Colchicine is a frequently used drug in rheumatological diseases. Acute promyelocytic leukemia developed in a patient who used colchicine for gouty arthritis since 10 years is presented and the possible relation between the long term use of colchicine and hematological malignancies is discussed.