Gülen Tüysüz
Istanbul University
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Featured researches published by Gülen Tüysüz.
Disease Markers | 2010
Yucel Erbilgin; Muge Sayitoglu; Ozden Hatirnaz; Ömer Doğru; Arzu Akcay; Gülen Tüysüz; Tiraje Celkan; Gonul Aydogan; Zafer Salcioglu; Cetin Timur; Lebriz Yuksel-Soycan; Umit Ure; Sema Anak; Leyla Agaoglu; Omer Devecioglu; Inci Yildiz; Ugur Ozbek
The NOTCH signaling pathway plays important role in the development of multicellular organisms, as it regulates cell proliferation, survival, and differentiation. In adults, it is essential for the T- or B-lymphocyte lineage commitment. NOTCH1 and FBXW7 mutations both lead the activation of the NOTCH1 pathway and are found in the majority of T-ALL patients. In this study, the mutation analysis of NOTCH1 and FBXW7 genes was performed in 87 pediatric T-ALLs who were treated on the ALL-BFM protocols. In 19 patients (22%), activating NOTCH1 mutations were observed either in the heterodimerization domain or in the PEST domain and 7 cases (10%) demonstrated FBXW7 mutations (2 cases had both NOTCH1 and FBXW7 mutations). We also analyzed the relationship of the mutation data between the clinical and biological data of the patients. NOTCH1 and FBXW7, NOTCH1 alone were found correlated with lower initial leucocyte counts which was independent from the sex and T- cell immunophenotype. However, NOTCH1 and FBXW7 mutations were not predictive of outcome in the overall cohort of pediatric T-ALLs.
Turk Pediatri Arsivi-turkish Archives of Pediatrics | 2017
Emre Çelik; Gül Nihal Özdemir; Gülen Tüysüz; Yücel Taştan; Halit Çam; Tiraje Celkan
Informed Consent: Written informed consent was obtained from patients’ parents who participated in this case. Peer-review: Externally peer-reviewed. Author Contributions: Literature Review - G.N.O.; Writer - G.N.O., E.C.; / Critical Review - Y.T., H.C., T.C.; Other - G.T. Conflict of Interest: No conflict of interest was declared by the authors. Financial Disclosure: The authors declared that this study has received no financial support.
Mycoses | 2014
Gülen Tüysüz; Nihal Ozdemir; Osman Faruk Senyuz; Senol Emre; Serda Kantarcioglu; Ibrahim Adaletli; Nuray Kepil; Çiğdem Tütüncü; Tiraje Celkan
We present a case of hepatic mucormycosis in a 9‐year‐old boy with acute lymphoblastic leukaemia. Despite long‐term use of combined liposomal amphotericin B and posaconazole therapy, the lesion persisted and could only be treated by surgical excision. After surgery, antifungal treatment was continued with posaconazole. On follow‐up, the patient had two episodes of ascending cholangitis which were responsive to intravenous antibiotics. He is doing well at the moment in remission for 2.5 years. Mucormycosis was long regarded as a fatal infection with poor prognosis. With early medical and surgical management, survival rates increase. Isolated hepatic mucormycosis is rare and only seven cases were reported in the literature up to now. We wanted to emphasise the role of early surgery in patients with hepatic mucormycosis in view of the literature.
Pediatric Hematology and Oncology | 2013
Dilek Uludağ; Nihal Ozdemir; Gülen Tüysüz; Ayşe Güler Eroğlu; Tiraje Celkan
Voriconazole is a triazole antifungal drug that is used to treat invasive fungal infections, especially aspergillus. Here, we report two children who had severe bradycardia associated with voriconazole at a dose of 12 mg/kg per day. Bradycardia resolved in 24 hours in both after decreasing the dose to 10 mg/kg per day. Heart rates were in normal limits on follow-up. Bradycardia may be a side effect of voriconazole treatment in children under immunosuppressive treatment. Heart rate should be monitored in patients receiving voriconazole and other triazole treatments.
Türk Patoloji Dergisi | 2013
Gülen Tüysüz; Nihal Ozdemir; Haluk Emir; Haydar Durak; Sergülen Dervişoğlu; Ibrahim Adaletli; Hilmi Apak
Renal cell carcinoma is a tumor that is well known for a high rate of metastasis to several locations like the lung, liver and bones. Skeletal muscle is a rare location for dissemination of the disease. Herein, we describe a 7-year-old boy who presented with flank pain. On physical examination, an abdominal mass located on the left kidney as well as a solid palpable lesion on the left upper arm were detected. Total nephrectomy with subsequent excision of the arm mass was performed. Pathology examination revealed presence of translocation renal cell carcinoma. The patient received α-interferon followed by multikinase inhibitor (Sorafenib) treatment but was lost due to progressive disease. This is the first description of a pediatric patient with skeletal muscle metastases of translocation renal cell carcinoma in the literature.
Turk Pediatri Arsivi-turkish Archives of Pediatrics | 2014
Gülen Tüysüz; Gül Nihal Özdemir; Tiraje Celkan
Informed Consent: Written informed consent was obtained from patient’s parents. Peer-review: Externally peer-reviewed. Author Contributions: Concept - G.N.O.; Design - T.C.; Supervision -T.C.; Funding - G.T.; Materials - G.T.; Data Collection and/or Processing - G.T.; Analysis and/or Interpretation - G.T., G.N.O.; Literature Review - G.N.O., G.T.; Writer - G.T.; Critical Review - T.C., G.N.O. Conflict of Interest: No conflict of interest was declared by the authors. Financial Disclosure: The authors declared that this study has received no financial support.
Archives of Disease in Childhood | 2014
Hilmi Apak; Nihal Ozdemir; Gülen Tüysüz; B Kutlubay; Ethem Erginöz; M Kucur
The objective of this study was to compare iron levels of infants fed with supplementary foods because of malnutrition,to those who were supported with complementary foods from sixth months of age, when the breast milk alone is not sufficient. Eighty-four healthy infants aged 6 to 9 months were enrolled. Infants without a nutritional problem, with sufficient iron stores, weighing over 10th percentile were enrolled in the control group, while babies weighting over 3rd percentile, who were not breastfed and did not take a balanced and sufficient diet, without a chronic diseases and who were not born preterm were enrolled in the study group. All of the infants were followed for 3 months. Physical examination findings and complete blood count, iron, iron binding, ferritin, zinc test results were recorded monthly. Infants with malnutrition who could not take breast milk were supported with a follow-up formula (Bebelac). Mean ages were 7.2 ± 1.28 and 7.3 ± 1.1 months in the study and control groups respectively. Statistically significant increase was demonstrated in the MCV and iron levels of the infants supplemented with follow-up formula. MCV decreased significantly in the control group. Mean ferritin values increased from 53.2 ± 41.8 mg/L to 64.7 ± 89.7 mg/L in the study group, while decreased from 42.8 ± 34.0 mg/L to 34.6 ± 29.3 mg/L in the control group. In the study group, significantly higher levels of ferritin were measured in the last assessment, compared to the control group. In conclusion, increase in the iron stores of follow-up formula fed infants was observed during the follow-up period.
Turk Pediatri Arsivi-turkish Archives of Pediatrics | 2013
Tiraje Celkan; Gülen Tüysüz
Tumor lizis sendromu tumor hucrelerinin hizli bir sekilde yikilmasiyla ortaya cikan ve yasami tehdit edebilen metabolik anormalliklerle seyreden klinik bir tablodur Bu metabolik anormallikler ani yikilan tumor hucrelerinden hucre ici iyon nukleik asit protein ve metabolitlerinin hucre disi siviya sizmasi sonucunda olusur Bu hizli salinan metabolitler vucudun normal hemostatik mekanizmasini bozarak uremi hiperurisemi hiperkalemi ve hiperfosfatemiye neden olabilir Tumor lizis sendromunda sikca gorulen hipokalsemi ise hiperfosfatemiye ikincil olarak ortaya cikar Tumor lizis sendromu genellikle kemoterapinin baslanmasindan sonra gorulse de nadiren hizli buyuyen tumorlerde malin hucrelerin kendiliginden yikimi sonucunda tedaviden once de ortaya cikabilir Cogalma hizi fazla tumor yuku yuksek olan Burkitt lenfoma ve akut lenfoblastik losemi gibi malinitelerde tumor lizis sendromu gorulme ihtimali daha yuksektir Tumor lizis sendromu gelismesini onlemek ve tedavinin esasini yogun hidrasyon yeterli diurez allopurinol ve veya rasburikaz tedavisi ile hiperuriseminin kontrolu serum elektrolitlerinin duzenlenmesi ve luzum halinde diyaliz tedavisi olusturur Gerekli onlemler alinmaz veya olusan klinik tablo tedavi edilmez ise metabolik anormallikler kanser hastalarinda bobrek yetersizligi kardiyak aritmi norolojik komplikasyon ve muhtemel ani olume neden olabilir Daha oncelerde her hastada uygulanan idrarin alkalizasyonu ise son yillarda pek onerilmemektedir ve bu konu halen tartismaya aciktir Bu yazida tumor lizis sendromu ve tedavisi sirasinda degisen yaklasimlar ve yeniliklerden bahsedilecektir Turk Ped Arfl 2013; 48: 188 94Tumor lysis syndrome is a clinical picture which occurs with the lysis of malignant cells and causes metabolic abnormalities that threatens life. These metabolic abnormalities are caused by the release of intracellular ions, nucleic acids, proteins and their metabolites from the instantly degraded tumor cells. These rapidly released metabolites can impair the body’s normal homeostatic mechanism and cause uremia, hyperuricemia, hyperkalemia and hyperphosphatemia. Hypocalcemia which is commonly seen in tumor lysis syndrome is secondary to hyperphosphatemia. Generally, tumor lysis syndrome occurs after the initiation of chemotherapy, but it is rarely observed in fast growing tumours before the treatment due to spontaneous lysis of malignant cells. The possibility of tumor lysis syndrome is higher in tumours with high proliferative rates and high tumour burden including Burkitt’s lymphoma and acute lymphoblastic leukemia. The principle of prophylaxis/treatment of tumour lysis syndrome includes virgous hydration, adequate diuresis, control of hyperuricemia with rasburicase or allopurinol, regulation of serum electrolytes and dialysis, if necessary. If the necessary measures are not taken or the clinal situation is not treated properly, metabolic abnormalities can cause renal insufficiency, cardiac arrhythmia, neurologic complications and propably sudden death in patients with cancer. Alkalization of urine used to be applied to all patients previously, but it is not recommended any longer and this issue is still open to debate. In this paper, new approaches and innovations in the treatment of tumor lysis syndrome are discussed. (Turk Arch Ped 2013; 48: 188-194)
Archives of Disease in Childhood | 2012
B Kutlubay; Nihal Ozdemir; Gülen Tüysüz; Hilmi Apak; Tiraje Celkan
Aim Glazmann thrombasthenia is a rare autosomal recessive disease characterized by defect in platelet aggregation. Here we report the management of children with Glazmann thrombasthenia followed at Cerrahpasa Medical Faculty Pediatric Hematology Department. Methods Nineteen patients’ (42% girls, 58% boys; median age: 10 months) files were retrospectively reviewed. Results The median age of the start of bleeding symptoms was 9 months (2 weeks-24 months). All patients presented with easy bruising and mucosal bleeding. Fourteen patients’ parents were consanguineous. In 15 patients, flow cytometry was performed. According to this, 7 had type I, 6 had type II and 2 had type III disease. Nine patients were treated by thrombocyte transfusion, tranexamic acid, recombinant active factor VII and fibrin glue as a single or combined therapy in invasive procedures; none of them had a major bleeding complication. Conclusion Bleeding control of invasive procedures may be challenging in children with Glazmann thrombasthenia; local treatments, DDAVP, steroid and antifibrinolytics may be used with success.
Disease Markers | 2010
Yucel Erbilgin; Muge Sayitoglu; Ozden Hatirnaz; Ömer Doğru; Arzu Akcay; Gülen Tüysüz; Tiraje Celkan; Gonul Aydogan; Zafer Salcioglu; Cetin Timur; Lebriz Yuksel-Soycan; Umit Ure; Sema Anak; Leyla Agaoglu; Omer Devecioglu; Inci Yildiz; Ugur Ozbek