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S Tsukada

Publications and source records attributed to S Tsukada.

133 records · Page 8Linked to original sources

Studies on the pigmentation of skin grafts: the ultrastructure of epidermal melanoxytes.

We carried out ultrastructural studies on the epidermal melanocytes in human skin autografts, before and after transplantation. On comparing the results with those described in our previous paper, the present findings are in accord with those light microscope findings. As we suggested earlier, the degree of pigmentation in a skin graft is probably due not only to quantitative changes in the transfer and formation of melanosomes, but also to the distribution, the degradation pattern, and the size of the melanosomes within the keratinocytes. Rupture of lysosomes, as a consequence of transplantation, may also contribute to the pigmentation of the skin graft.

Adolescent↗

Nucleotide deletion of T cell receptor V gamma 2 and J gamma 2 coding sequences at V gamma 2-J gamma 2 junctions in immature B cell lines.

Immature B cell lines transformed with a temperature-sensitive mutant of Abelson murine leukaemia virus undergo preferentially V gamma 2 to J gamma 2 joinings during culture at a non-permissive temperature (39 degrees C). Here we examined nucleotide addition and deletion at the V gamma 2-J gamma 2 junctions in these V gamma 2 to J gamma 2 joinings, in comparison with the V gamma 2-J gamma 2 junctional sequences reported previously in T cells. Forty-eight V gamma 2-J gamma 2 junctions were PCR-amplified and sequenced. Only three of 48 V gamma 2-J gamma 2 junctions had nucleotide addition. The average nucleotide deletion of V gamma 2 coding sequences at the V gamma 2-J gamma 2 junctions was 6.9 nucleotides in immature B cells and 5.1 nucleotides in T cells (p less than 0.05). Also, the average nucleotide deletion of J gamma 2 coding sequences at the V gamma 2-J gamma 2 junctions was 3.1 nucleotides in immature B cells and 1.9 nucleotides in T cells (p less than 0.01). The average of total number of the deleted nucleotides at the V gamma 2-J gamma 2 junctions was 10.0 nucleotides in immature B cells and 7.0 nucleotides in T cells (p less than 0.01). No correlation was found between the extent of the nucleotide deletion of the V gamma 2 coding sequence and that of the J gamma 2 coding sequence at each V gamma 2-J gamma 2 junction in immature B and T cells. These results demonstrated that nucleotide deletion at the V gamma 2-J gamma 2 junctions was significantly wider in immature B cells than in T cells.

Animals↗