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Biomedical subjects

M Nakazono

Publications and source records attributed to M Nakazono.

106 records · Page 6Linked to original sources

Biodegradable material for bladder reconstruction.

The objective of this study was to develop a biodegradable material for use in reconstructive surgery of the bladder to serve a temporary function until normal regrowth of the host's tissue is completed. The biodegradable material can serve as a base over which the new bladder can regenerate. At the conclusion of the regrowth of the new tissue, the temporary material could be consumed by the body and therefore not have to be removed. Material evaluation showed that 70% acetic anhydride treated bovine pericardium was digested and dissolved in 4 weeks when implanted subcutaneously in dogs. Based upon this, supplementation of the bladder using this material was performed on 5 dogs. One dog showed urinary leakage and was sacrificed after 1 week. In 3 dogs examined 4, 6, and 48 weeks after implantation, respectively, the implanted material had been dissolved. In one animal autopsied at 10.5 months, a small remnant of the material still remained. Post-operative observation of the animals, excretory pyelocystograms and cystometry confirmed that the material applied was useful for experimental urinary bladder supplementation.

Acetates↗

Evolutionary variations in DNA sequences transferred from chloroplast genomes to mitochondrial genomes in the Gramineae.

The transfer of fragments of DNA from chloroplast genomes to mitochondrial genomes is considered to be a general phenomenon in higher plants. In the present study, Southern hybridization, together with amplification by PCR and DNA sequencing techniques, was used to examine the regions homologous to chloroplast rps19 in the mitochondrial genomes of several gramineous plants. In all the mitochondrial DNAs from the gramineous plants examined, except for that from wheat, the transferred fragments of chloroplast DNA were found to be maintained and the same junctions of mitochondrion-specific and chloroplast-like sequences were found at one terminus. This finding indicates that the transfer of the chloroplast sequence occurred in the distant past during the evolution of gramineous plants. Subsequent analysis revealed that the fragments had been variously rearranged among species with respect to the other terminus. Considering the current diversity of this one particular transferred fragment of chloroplast DNA, we propose that chloroplast-derived DNA sequences that have lost their original functions tend to be rearranged during evolution in mitochondrial genomes.

Base Sequence↗