Yazar "Stout, M" seçeneğine göre listele

Listeleniyor 1 - 2 / 2
  • Küçük Resim Yok
    Öğe
    Degradation of vincristine by myeloperoxidase and hypochlorous acid in children with acute lymphoblastic leukemia
    (Pergamon-Elsevier Science Ltd, 2003) Özgen, O; Türköz, Y; Stout, M; Özugurlu, F; Pelik, F; Bulut, Y; Aslan, M
    Vincristine (VCR) is an effective drug against acute lymphoblastic leukemia (ALL), many solid tumors, but not acute myeloid leukemia. It has been hypothesized that resistance of myeloblasts to VCR is related to myeloperoxidase (MPO) and production of hypochlorous acid (HOCl). We investigated the relationship between VCR degradation and MPO expression and serum HOCl concentrations in pediatric patients with ALL, lymphoma and solid tumors. We studied the sera from 43 children, of which 23 were newly diagnosed and as yet untreated cancer patients, 10 on chemotherapy and 10 healthy control subjects. Patients' sera were incubated with VCR alone or in the presence of taurine (T) or acetaminophen (APAP) and post-incubation VCR and HOCL concentrations were measured. Significant correlations between serum MPO expression, HOCl concentrations and VCR degradation were seen. In the chemotherapy group, MPO-positive patients produced high levels of HOCl and reciprocally low post-incubation VCR levels. HOCl and VCR concentrations in this group were significantly different than other groups studied. Both APAP and T inhibited VCR degradation in the sera of the chemotherapy group but not to the same degree. The effects seen here were consistent for both ALL and the lymphoma/solid tumor cases. Our results indicate that HOCl can increase VCR degradation in vitro in the serum and this effect is significantly more pronounced in pediatric patients undergoing chemotherapy. (C) 2003 Elsevier Science Ltd. All rights reserved.
  • Küçük Resim Yok
    Öğe
    Hypochlorous acid for accidental vincristine overdose: A preliminary experimental study
    (Inst Exp Pathol Oncol Radiobiol, 2003) Ozgen, U; Stout, M; Turkoz, Y; Ozugurlu, F; Kutlu, NO; Soylu, H; Koltuksuz, U
    Aim: to investigate the potential efficacy of in vivo treatment of accidental vincristine (VCR) overdose using hypochlorous acid (HOCl). Methods: 24 New Zealand rabbits were divided into 4 groups as control, HOCl-treated, VCR + treated and HOCl + VCR-treated, and their clinical and laboratory indexes were examined. Results: there were no clinical and laboratory abnormalities observed in control and HOCl group subjects. All rabbits died after quadriplegia and respiratory insufficiency in VCR and HOCl + VCR groups. Bone marrow suppression was more pronounced and onset of the neurotoxicity was early in VCR group compared to HOCl + VCR group subjects. Serum half-life of VCR was lower in HOCl + VCR group animals suggesting a contribution of HOCl in eliminating VCR resulting in the observed clinical and laboratory differences in these two groups. Conclusion: although further research is necessary, our results indicate a potential role for HOCl in the treatment of accidental VCR overdose.