A phylogenetic tree was constructed from 245 globin amino acid sequences. Of the six plant globins, five represented the Leguminosae and one the Ulmaceae. Among the invertebrate sequences, 7 represented the phylum Annelida, 13 represented Insecta and Crustacea of the phylum Arthropoda, and 6 represented the phylum Mollusca. Of the vertebrate globins, 4 represented the Agnatha and 209 represented the Gnathostomata. A common alignment was achieved for the 245 sequences using the parsimony principle, and a matrix of minimum mutational distances was constructed. The most parsimonious phylogenetic tree, i.e., the one having the lowest number of nucleotide substitutions that cause amino acid replacements, was obtained employing clustering and branch-swapping algorithms. Based on the available fossil record, the earliest split in the ancestral metazoan lineage was placed at 680 million years before present (Myr BP), the origin of vertebrates was placed at 510 Myr BP, and the separation of the Chondrichthyes and the Osteichthyes was placed at 425 Myr BP. Local "molecular clock" calculations were used to date the branch points on the descending branches of the various lineages within the plant and invertebrate portions of the tree. The tree divided the 245 sequences into five distinct clades that corresponded exactly to the five groups plants, annelids, arthropods, molluscs, and vertebrates. Furthermore, the maximum parsimony tree, in contrast to the unweighted pair group and distance Wagner trees, was consistent with the available fossil record and supported the hypotheses that the primitive hemoglobin of metazoans was monomeric and that the multisubunit extracellular hemoglobins found among the Annelida and the Arthropoda represent independently derived states.

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Autoxidation of bovine oxymyoglobin to metmyoglobin induces co-oxidation of epinephrine to adrenochrome. This co-oxidation is markedly inhibited by superoxide dismutase [EC 1.15.1.1]. Electron transfer from oxymyoglobin to ferricytochrome c is partially inhibited by superoxide dismutase. These results indicate that autoxidation of oxymyoglobin results in generation of superoxide radicals. Autoxidation of oxymyoglobin is accelerated by superoxide dismutase and partially inhibited by catalase [EC 1.11.1.6].

Mortality of patients who underwent percutaneous endoscopic gastrostomy appears to be high. In particular, the long-term prognosis was poor for patients with hypoalbuminemia, and this procedure is probably not preferred for patients with recurrent aspiration pneumonia.

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