RESUMO
A third DNA polymerase 'C' with low molecular weight was isolated and purified 3700-fold from ground hyphae of Neurospora crassa WT 74 A, which shows similarities to beta- and gamma-polymerases from higher eukaryotes: preference for poly(rA)(dT) as a template/primer, inhibition by p-chloromercuribenzoate, resistance against N-ethylmaleimide up to 10 mmol/l, and molecular weight of about 40000. This polymerase elutes as a distinct peak from DEAE-cellulose at 0.60 mol/l KCl and has an optimum for K+ at 2-20 mmol/l, for Mn2+ at 0.8 mmol/l, for Mg2+ at 4.0 mmol/l, the pH optimum is 8.0. Its Km is 1.5 mumol/l using dTTP as substrate. The enzyme activity described here is free of endonuclease but contains detectable amounts of exonuclease.
Assuntos
Neurospora crassa/enzimologia , Neurospora/enzimologia , Nucleotidiltransferases/isolamento & purificação , Cromatografia de Afinidade , Cinética , Peso Molecular , Nucleotidiltransferases/metabolismo , DNA Polimerase Dirigida por RNA/metabolismo , Reagentes de Sulfidrila/farmacologia , Moldes GenéticosRESUMO
10 patients with advanced non-Hodgkin's lymphoma of low malignancy were treated with partially purified HulFN-beta. They received daily i.v. infusions of 4.5 X 10(6) IU for 4 weeks, followed by 9 X 10(6) IU daily for 2 weeks. Patients with stable disease during this period received consolidation therapy with 4.5 X 10(6) IU three times per week for a maximum of 20 weeks. Six out of 10 patients had progressive disease after the initial 6 week treatment and 4 had stable disease. Two of the latter developed progressive disease during consolidation therapy, one had a complete remission of minimal bone marrow involvement, and one was in partial remission with a loss of bone marrow infiltration but unchanged lymph node enlargement.
Assuntos
Interferon Tipo I/uso terapêutico , Linfoma/tratamento farmacológico , Adulto , Idoso , Feminino , Humanos , Interferon Tipo I/efeitos adversos , Masculino , Pessoa de Meia-IdadeRESUMO
During recent years clinical trials have shown that human leukocyte interferon (HuIFN-alpha) may be useful in the treatment of cancer, but very little has been done concerning the possible use of human fibroblast interferon (HuIFN-beta). Treuner et al. recently reported the successful treatment of a nasopharyngeal carcinoma with HuIFN-beta: in the course of IFN-therapy a HuIFN-beta neutralizing activity appeared in the serum of this patient. We report here that such activity is due to IgG antibodies--this study is the first to present evidence for antigenicity of IFN in a homologous system.
Assuntos
Formação de Anticorpos , Interferons/imunologia , Fibroblastos , Humanos , Imunoterapia , Interferons/uso terapêutico , Neoplasias Nasofaríngeas/terapiaAssuntos
Interferons/uso terapêutico , Avaliação de Medicamentos , Fibroblastos , Fibrossarcoma/tratamento farmacológico , Humanos , Interferons/administração & dosagem , Interferons/sangue , Leucemia/tratamento farmacológico , Neoplasias Nasofaríngeas/tratamento farmacológico , Neuroblastoma/tratamento farmacológicoRESUMO
Two DNA-dependent DNA-polymerases (E.C. 2.7.7.7) are partially purified from the high speed supernatant of mechanically disrupted hyphae of Neurospora crassa WT 74A. Some properties such as temperature and pH optimum and theoptimal concentrations for Mg2+, Zn2+, NH4+ and Na+ are very similar. On the other hand these enzymes show different properties on ion-exchange columns, are well distinguished by molecular weight (147 000 d and 110 000 d for A and B resp.) and the stimulation by K+ differs (K+ optimum for A: 5-70 mM and for B: 45 mM). Mn2+ and Zn2+ inhibit incorporation of deoxyribonucleoside monophosphates between 70 and 90%. Our best preparations so far have specific activities of 13 200 units/mg protein for A and 12 000 units/mg protein for B.