Search PubMed⌕ Search

Biomedical subjects

N Amaya

Publications and source records attributed to N Amaya.

4 recordsLinked to original sources
PubMed1999

Successful salvage treatment with irinotecan (CPT-11) of recurrent malignant lymphoma in an aged patient; and CPT-11 pharmacokinetics.

A 72-year-old patient with relapsed non-Hodgkin's lymphoma (diffuse large B-cell type) in the tongue was treated with irinotecan (CPT-11) as the 4th salvage therapy. A two-thirds reduced dose of 40 mg/m2 of CPT-11 was administered, as were granulocyte-colony stimulating factor and antidiarrheal agents. Complete remission was achieved. Although grade 3 leukopenia and grade 1 diarrhea were observed, these adverse reactions did not interrupt the treatment schedule and CPT-11 was administered without interruption for a total of 12 weeks. Despite the dose reduction, the area under the concentration-time curve of SN-38, the active metabolite of CPT-11, was nearly equal to the values reported in phase I and II studies of CPT-11. The patient's ratio of SN-38 to the SN-38 glucuronide (SN-38G) was low, suggesting a low risk of diarrhea. The optimal dose modification provided a sufficient amount of the active metabolite. Supportive therapy managed therapy-related toxicities and resulted in a stable treatment schedule. This is a rare case of a patient successfully treated with CPT-11 after a 4th relapse, in which the agent was administered at the total dose of 960 mg/m2, despite the patient's advanced age.

Aged↗
PubMed1983

Degradation of myelin basic protein by calcium-activated neutral protease (CANP) in human brain and inhibition by E-64 analogue.

A calcium-activated neutral protease (CANP) was extracted from human brain and partially purified. The activity was measured using alkali-denatured casein (Hammersten) as a substrate. The optimum pH was around 7.0. The activity required the presence of calcium ions, maximum activity was obtained with over 5 mM calcium ions. The Km for the casein concentration was about 1.62 mg/ml. The activity of CANP was inhibited by one of the thiol protease inhibitors, E-64 analogue (E-64-a). The rate of inhibition was about 50% at an E-64-a concentration of 10(-5)M. This CANP degraded selectively basic protein in myelin proteins and the degradation was inhibited by E-64-a or EGTA. The role of the brain CANP in the process of demyelination was suggested by this study.

Brain↗