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Biomedical subjects

H Hashizume

Publications and source records attributed to H Hashizume.

At least 181 records · Page 10Linked to original sources

Phosphorylation of specific polypeptides in isolated murine splenocyte nuclei which is controlled by cyclic nucleotides.

Murine splenocyte nuclei were phosphorylated with a less than 10(-5) M concentration of [gamma-32P]ATP at 0 degrees C and the phosphorylated nuclear proteins were analyzed by SDS-polyacrylamide gel slab electrophoresis and Sephadex gel filtration column chromatography. Two polypeptides of 10K and 11K daltons were predominantly phosphorylated. These polypeptides were likely linked by a disulfide bond to form a nonhistone protein of 21K daltons. Both phosphoserine and phosphothreonine were detected in the hydrolysate of the 10.5K dalton polypeptide, while phosphoserine was predominant in the 10K dalton polypeptide. Maximal activation of phosphorylation by cAMP of both polypeptides was shown at a concentration of 10(-6) M. On the contrary, cGMP activated phosphorylation of the 10K dalton polypeptide at 10(-8) M and at 10(-4) M. The phosphorylation of the 10.5K polypeptide was not activated by 10(-4) M cGMP and suppression of the phosphorylation was seen in both polypeptide chains by cAMP at higher concentrations.

Amino Acids↗

Mitogenic effect of cytoplasmic membranes and a cytoplasmic fraction of Staphylococcus aureus L-forms on human peripheral blood lymphocytes.

The cytoplasmic membranes and a cytoplasmic fraction of Staphylococcus aureus L-forms increased the incorporation of [3H]thymidine by human lymphocytes in the presence of fetal bovine serum. Both fractions stimulated cord blood lymphocytes as well as adult peripheral lymphocytes, suggesting the possibility that the observed effect was not due to an antigen-specific reaction, but to an immunologically nonspecific action. The membrane mitogen(s) was resistant to trypsin, although it was partially solubilized by trypsin treatment. The mitogen(s) could not be extracted with a chloroform-methanol mixture (2:1, v/v), although the chloroform-methanol soluble fraction was strongly mitogenic to murine splenocytes. Human serum which was added to the assay system in place of fetal bovine serum definitely suppressed the mitogenic effect of both cytoplasmic membranes and the cytoplasmic fraction, especially the latter.

Cytoplasm↗

Mitogenic activity of cytoplasmic membranes isolated from L-forms of Staphylococcus aureus.

Cytoplasmic membranes of L-forms of Staphylococcus aureus exerted a strong mitogenic effect on splenocytes of athymic nude mice as well as normal mice, while a cytoplasmic fraction of the same bacteria did not show definite mitogenicity. The mitogenic principle(s) of the membrane fraction was resistant to treatment with trypsin and was heat stable (at 100 C for 10 min). The active principle(s) in the insoluble residue of the membrane fraction digested with trypsin was not extracted with cold acetone, but could be solubilized by extraction with a cold chloroform-methanol mixture (2:1, v/v). The mitogenic principle(s) in the extract was fractionated by silicic acid column chromatography. Among five fractions separated by chromatography, fractions eluted with chloroform-methanol mixtures (1:1 and 1:20, v/v) were found to be strongly mitogenic. The cytoplasmic membranes of the L-forms also exerted a definite mitogenic effect on guinea pig splenocytes, but not on the thymocytes.

Animals↗

Three-dimensional architecture and development of lumber intervertebral discs.

The three-dimensional architecture of the collagen framework of human lumbar intervertebral discs was studied with scanning electron microscopy and polarized light microscopy concentrating on the fibrillar interconnection between the intervertebral disc and the vertebral bodies. The fibrillar framework of the annulus fibrosus and the cartilage end-plates encircled the nucleus pulposus as a closed-pack system in the adult. This closed-pack system developed in the seventh embryonic month and was completed by the tenth month. In general, fibrils composing the framework in the fetus were thinner than in the adult. There was no fibrillar interconnection between the cartilage end-plate and subchondral bone. In the inner one-third of the annulus, obliquely oriented fibrillar lamellae interconnected with the cartilage end-plate. In the outer two-thirds, the fibrillar bundles of the lamellae were firmly anchored into the vertebral bodies. This fibrillar anchoring system was already present in the full-term fetus although the vertebral rim was not ossified.

Adolescent↗