Biomedical subjects
Publications and source records attributed to N Maeda.
Infection of primary human cells with a rubella variant carrying DNA polymerase activity resulted in persistent infection; infection with wild type virus caused death of the infected cells and a cytopathic effect.
Explore the source record for details and available documents.
A case of metastatic choriocarcinoma involving the mandible is reported. This case is analyzed for the potentiality of immunologic defense by utilizing tuberculin test and scoring the rate of blast formation of peripheral blood lymphocytes by phytohemagglutinin, resulting in a greatly decreased ability of cellular immunity.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
The amino acid sequences of erabutoxins a and b were re-examined. The previously reported sequence of Ser-Glu at positions 21 and 22 of erabutoxins was corrected to Glu-Ser.
Human erythrocytes, untreated and glutaraldehyde-treated, were spin labeled with three kinds of fatty acid labels, and their electron spin resonance (ESR) spectra were studied in detail at various temperatures. 1. The better spectral resolution could be obtained by packing the erythrocytes in a hematocrit capillary tube, because of the preferential parallel orientation of the cylindrical axes of erythrocyte-disc to the centrifugal axis. 2. It was demonstrated by the incorporation and the release of the labels that the membrane possessed two kinds of the fatty acid "sites": the tightly and weakly binding "sites" at the approximate molar ratio of 1:1. The rough estimates of the binding constants were obtained, which reproducibly varied with the blood donors over a period of a year. 3. The temperature dependency of the ESR spectra revealed the presence of two distinct phases, perhaps the solid and fluid phases. With lowering of the temperature, the fluid phase became more solid but the solid phase unchanged. The pretreatment of the erythrocytes with glutaraldehyde increased the amount of the frozen phase, corresponding to the decrease of the membrane flexibility.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
The oxygen dissociation curve of partially NO-liganded hemoglobin of human erythrocytes is measured. As the percentage of NO ligation increases, the affinity of nonliganded hemoglobin for oxygen increases and the heme-heme interaction decreases; furthermore, methemoglobin is formed. Therefore, NO affects the oxygen transport function of hemoglobin, decreasing the oxygen supply to peripheral tissues, because of (1) simple diminution of the available hemoglobin by the tightly bound NO, (2) the high affinity of hemoglobin for oxygen, and (3) the inevitable formation of methemoglobin.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Aipysurus laevis venom was chromatographed on CM-cellulose and Bio-Rex 70 columns. Three neurotoxic components, toxins Aipysurus laevis a, b and c, were isolated. The toxins a, b and c corresponded to 22, 33 and 21% respectively of the proteins in the original venom, and accounted for almost all the lethal activity of the venom. The three toxins a, b and c were monodisperse on disc electrophoresis at pH4; toxins a and b moved at the same velocity and c a little faster. They were monodisperse also on sodium dodecyl sulphate-polyacrylamide-disc-gel electrophoresis, giving a molecular weight of 7600. The molecular weight of toxin b estimated by gel filtration was 7000. The amino acid sequence analyses of these toxins revealed that they consisted of 60 amino acid residues and that Aipysurus laevis b was [25-methionine, 28-arginine] Aipysurus laevis a. Aipysurus laevis c was [28-lysine] Aipysurus laevis a, the tryptic peptide sequence relying on homology. The LD50 values of these toxins for 20g mice were 0.076 mug/g body wt. They inhibited the acetylcholine-induced contracture but did not affect the CKl-induced contracture of the isolated muscle.
Pyridoxal 5'-phosphate (PLP), an allosteric effector for the oxygenation of haemoglobin, was incorporated readily into erythrocytes and disappeared from them by simple passive diffusion. The disappearance of PLP from the cells was accelerated by the generation of 2,3-DPG in a medium of inosine, pyruvate and phosphate. The oxygen dissociation curve measured at an extracellular pH of 7.4 demonstrated that PLP incorporated into the cells also lowered the oxygen affinity and that PLP functionally compensated for a metabolically reduced 2,3-DPG. However, the dependency of the oxygen affinity on the intracellular PLP concentration showed a different pattern from the observed for 2,3-DPG. On the other hand, the lowering of intracellular pH by organic phosphates accumulated in the cells was much larger with PLP than with 2,3-DPG. The peculiar relationship between the oxygen affinity of erythrocytes and the intracellular PLP concentration is discussed in detail. The present study may offer a new prospect for the preservation of blood with a normal function.