Browsing by Subject "Bone marrow transplantation"

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    Donor cell leukemia in a patient developing 11 months after an allogeneic bone marrow transplantation for chronic myeloid leukemia
    (Wiley, 2006) Ataergin, S.; Arpaci, F.; Cetin, T.; Guran, s.; Yakicier, C.; Beyzadeoglu, M.; Ozet, A.
    A 38‐year‐old female with chronic myeloid leukemia underwent an allogeneic bone marrow transplantation from her full‐matched brother. Eleven months later, she readmitted with an acute leukemia that was shown to be of donor origin. The patient never achieved a remission even after chemotherapies with cytarabine and mitoxantrone, donor lymphocyte infusion, and second allogeneic peripheral blood stem cell transplantation. Donor cell leukemia (DCL) is sometimes misdiagnosed as relapse by clinicians and the real incidence may be higher than expected. Cytogenetic and molecular techniques may be helpful to clarify the issue of the leukemia. The current case is another case of DCL reported in the literature after an allogeneic transplant for a kind of leukemia. Am. J. Hematol. 81:370–373, 2006
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    Evaluation of chimerism with DNA polymorphisms in bone marrow transplantation
    (International Children's Center (I C C), 1997) Özbek, U.; Vural, B.; Kalayoǧlu, S.; Soysal, T.; Bilgen, H.; Yavuz, S.; Anak, S.; Sargın, D.; Gedikoǧlu G.; Ferhanoǧlu, Burhan; Akoǧlu, T.; Tangün, Y.; Özçelik, Tayfun
    Evaluation of chimeric status following allogenlc BMT is an Important tool for monitoring the replacement of host cells with donor cells and for determining the risk of relapse. Polymorphic DNA sequences can be used as powerful markers in identification of donor/recipient genotype differences, even between close relatives. Polymerase chain reaction (PCR) amplification of three variable number of tandem repeat (VNTR) loci and five single-locus polymorphisms (SLP) was used to identify chimerism in 40 recipient-donor pairs. Mixed chimerism was present in 11 patients, and complete chimerism in 29. This PCR method is a rapid and sensitive assay to detect engraftment and evaluate relapse potential, and thus is very useful in the clinical management of BMT patients.
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    Jnk1 deficiency in hematopoietic cells suppresses macrophage apoptosis and increases atherosclerosis in low-density lipoprotein receptor null mice
    (Lippincott Williams and Wilkins, 2016) Babaev, V. R.; Yeung, M.; Erbay, E.; Ding, L.; Zhang, Y.; May, J. M.; Fazio, S.; Hotamisligil, G. S.; Linton, M. F.
    Objective - The c-Jun NH 2 -terminal kinases (JNK) are regulated by a wide variety of cellular stresses and have been implicated in apoptotic signaling. Macrophages express 2 JNK isoforms, JNK1 and JNK2, which may have different effects on cell survival and atherosclerosis. Approach and Results - To dissect the effect of macrophage JNK1 and JNK2 on early atherosclerosis, Ldlr-/- mice were reconstituted with wild-type, Jnk1-/-, and Jnk2-/- hematopoietic cells and fed a high cholesterol diet. Jnk1-/- →Ldlr-/- mice have larger atherosclerotic lesions with more macrophages and fewer apoptotic cells than mice transplanted with wild-type or Jnk2-/- cells. Moreover, genetic ablation of JNK to a single allele (Jnk1+/- /Jnk2-/- or Jnk1-/- /Jnk2+/-) in marrow of Ldlr-/- recipients further increased atherosclerosis compared with Jnk1-/- →Ldlr-/- and wild-type→Ldlr-/- mice. In mouse macrophages, anisomycin-mediated JNK signaling antagonized Akt activity, and loss of Jnk1 gene obliterated this effect. Similarly, pharmacological inhibition of JNK1, but not JNK2, markedly reduced the antagonizing effect of JNK on Akt activity. Prolonged JNK signaling in the setting of endoplasmic reticulum stress gradually extinguished Akt and Bad activity in wild-type cells with markedly less effects in Jnk1-/- macrophages, which were also more resistant to apoptosis. Consequently, anisomycin increased and JNK1 inhibitors suppressed endoplasmic reticulum stress-mediated apoptosis in macrophages. We also found that genetic and pharmacological inhibition of phosphatase and tensin homolog abolished the JNK-mediated effects on Akt activity, indicating that phosphatase and tensin homolog mediates crosstalk between these pathways. Conclusions - Loss of Jnk1, but not Jnk2, in macrophages protects them from apoptosis, increasing cell survival, and this accelerates early atherosclerosis.
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    A retrospective comparison of allogeneic peripheral blood stem cell and bone marrow transplantation results from a single center: a focus on the incidence of graft-vs.-host disease and relapse
    (Elsevier, 1999) Üstün, C.; Arslan, Ö.; Beksaç, M.; Koç, H.; Gürman, G.; Özçelik, T.; Yilmaz, B.; İlban, O.; Akan, H.; Özcan, M.; Demirer, T.; Uysal, A.; Konuk, N.; Arat, M.; Dilek, İ.; Çelebi, H.; Coskun, H. S.
    To detect the effect of the stem cell source, allogeneic peripheral blood stem cell transplantations (alloPBSCTs) performed between 1995 and 1997 from human leukocyte antigen (HLA)-identical siblings in 40 patients with acute and chronic hematological disorders were compared with a historical group of 40 patients with similar variables who had received allogeneic bone marrow transplants (alloBMTs) between 1993 and 1995. Patients in both groups were identical except that both the recipient and the donor ages were, on average, higher in the alloPBSCT group (26 vs. 36 [p = 0.005] and 27 vs. 32 [p = 0.024], respectively). Patients received similar therapy excluding posttransplant granulocyte colony-stimulating factor administration (97% in alloBMT vs. 12.5% in alloPBSCT). The median time to reach neutrophil counts >0.5×109/L and platelet counts >20×109/L was 13 and 14 days, respectively, in patients receiving alloPBSCTs compared with 19 and 27 days in patients receiving alloBMTs (p = 0.0014 and p = 0.0002). The alloPBSCT group required similar transfusions of red blood cells or platelets. The incidence of grade II-IV acute graft-vs.-host disease (aGVHD) was similar in both groups. However, chronic GVHD (cGVHD) of all grades developed in 78.1% of patients in the alloPBSCT group after a median follow-up period of 12.5 (range 0.5-34) months. In alloBMT recipients, cGVHD of all grades developed in 21.4% after a median follow-up period of 38 (range 0.5-62) months (p = 0.00001). Day 100 transplant-related mortality was also similar: 20% (8 of 40) in the alloBMT patients and 17.5% (7 of 40) in the alloPBSCT group. Although not statistically significant, a relatively higher relapse rate occurred in the alloBMT group (21.4 vs. 10.7%). The estimated disease-free survival in month 24 was 51.3% for alloBMT and 54.6% for alloPBSCT, and the estimated overall survival in month 24 was 56.1% for alloBMT and 64.6% for alloPBSCT. In conclusion, this retrospective comparison suggests that alloPBSCT from HLA-identical donors is associated with faster engraftment, fewer transfusions, and no greater incidence of aGVHD, but a high incidence of cGVHD.
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    Türkiye’deki kemik iliği nakli uygulamalarının tarihçesi
    (Bilkent University, 2021) Aksu, Ahmet Burak; Geçit, Zeynep Begüm; Aygar, Emre; Ecerkale, Begüm; Turan, Zeynep
    Kemik iliği nakli lösemi, lenf bezi kanseri ve kemik iliği yetmezliği gibi hastalıkların tedavisinde kullanılan ve sağlıklı bir vericiden toplanmış olan kemik iliğinin veya kemik iliği kök hücrelerinin hastaya nakledilmesi ile gerçekleştirilen bir tedavi yöntemidir. Kemik iliği nakli yöntemi dünyada 1960’lı yıllar itibariyle kullanılmaya başlanmış ve 1970’li yıllar itibariyle kullanımı yaygınlaşmıştır. Türkiye’de yöntemin ilk uygulanışı resmi verilere göre 1978 yılına dayansa da kemik iliği naklinin yaygın bir tedavi yöntemi haline gelmesi uzun sürmemiştir. Türk hekimlerinin başarılı uygulamaları sayesinde Türkiye’deki nakil uygulamaları dünyadaki gelişmeleri kısa sürede yakalamış ve Türkiye dünyanın önemli nakil merkezlerinden biri haline gelmiştir. 1978 yılında Hacettepe Üniversitesi bünyesinde Prof. Dr. Korkut Özerkan ile başlayan kemik iliği nakli uygulamalarını 1984 yılında GATA’da ilk otolog kemik iliği naklini gerçekleştiren Prof. Dr. Önder Berk ve ekibi ve daha sonra 1992 yılında gerçekleştirilen ilk periferik kök hücre nakli uygulaması ile Ankara Üniversitesi takip etmiştir. Dünyada olduğu gibi Türkiye’de de çocuk hastaların kemik iliği nakli yöntemiyle tedavisi erişkin hastalara göre daha geç başlamış ve 1990’lı yılların başında ilk uygulama İstanbul Üniversitesi Tıp Fakültesi’nde gerçekleştirilmiştir. Bu araştırmada Türkiye’deki kemik iliği naklinin tarihi, bu tarihi yaşayanların gözünden sosyal ve kısmen bilimsel yönden incelenmiştir. Aynı zamanda süreç içerisinde yaşanan zorluklar, yüksek teknoloji ve üst düzey uzman insan kaynağı gerektiren bu işlemin Türkiye’de yaygınlaşması, gelişmesi ve hekimlerin yetişmesinde hangi yöntemlerin kullanıldığı gibi bilgiler de anlatılmıştır.