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R T Moore

Publications and source records attributed to R T Moore.

At least 19 recordsLinked to original sources

Evolutionary advances in the higher fungi.

In this report the phrase 'evolutionary advances' is used in three ways: 1. to describe monophyletic changes perceived within a lineage; 2. to describe evolutionary sequences that appear to have become parallel/convergent; 3. to describe major transitions inferred between primary taxa. In monophyletic evolution the changes occur within a specific lineage that arises from a common ancestor, e.g., modern Man, horses, rusts. In parallel/convergent evolution different lineages respond similarly over time to environmental challenges and opportunities and come to acquire a great deal of comparability (e.g., Webster, 1987). Such lineages may be designated as separate taxa, e.g., similarities in marsupial and placental carnivores, or, if the polyphyleticism is cryptic, as a collective taxon, e.g., Aves, the class of birds, the obsolete Amentiferae for catkin bearing plants, the Gasteromycetes, and lichens. In major transitions there are significant paradigm shifts in which evolutionary changes from one predominant life style pattern to another are accompanied by increases in complexity (see Smith & Szatháry, 1995), e.g., symbiosis, the water to land transition, the changes between the phyla of land fungi. Three particular terms are used in evaluating evolutionary relationships (Moore, 1996a): homology, paramology, and analogy. Homology, from Darwin's theory of common descent, is the phenomenon of having a common historical origin but not necessarily the same final structure or function (e.g., vertebrate forelimbs). Paramology (Moore, 1971) applies to inferred relationships in evolutionary schemes based on contemporary forms that lack fossil antecedents, e.g., the various phylogenetic interpretations of prokaryotes, algae, and fungi; Boekhout et al. (1993) have evaluated the taxonomic resolution of a variety of morphologic, biochemical, physiological, and molecular characters (Table 1). Analogy is generally applied to similar forms that are unrelated, e.g., insect/vertebrate wings; prokaryote/eukaryote flagella. It should also be borne in mind that, in a given taxon, biotrophism (Coffey, 1975) is an advanced character (Health, 1987) over, respectively, weaker parasitism, symbiotism, commensalism, and freeliving and that seemingly simple or less differentiated forms can be, and more than likely than not are, reduced, polyphyletic, and specialized rather than ancient and rudimentary, e.g., yeasts (Hoog et al., 1988; Kurtzman & Fell, 1996; Moore, 1988b; 1996a).

Biological Evolution↗

The Rey AVLT recognition memory task measures motivational impairment after mild head trauma.

The effect of financial incentives on Rey AVLT recognition memory performance was assessed. Clinically referred mild head trauma (MHT) patients with financial incentives were compared to patients with neurologically documented brain dysfunction who did not have financial incentives. The MHT group was subdivided into a group with strong performance on a measure of motivation, the Portland Digit Recognition Test (PDRT), and a group with weak performance on the PDRT. The resulting three groups were equated on Rey AVLT acquisition, age, and education. The MHT subgroup with poor PDRT scores also was significantly impaired on recognition memory. In the total sample the prevalence of recognition scores of less than 6 correct was 27% in the MHT group and 5% in the brain dysfunction group. We conclude that severe Rey AVLT recognition memory impairment likely reflects motivation to exaggerate deficits, at least in MHT patients with no neurological evidence of brain injury.

Journal Article↗

Effect of thrombin inhibition on the dynamics of thrombolysis and on platelet function during thrombolytic therapy.

To evaluate the effect of thrombin on the dynamics of thrombolysis, we infused rabbits with heparin or hirudin alone or in conjunction with tissue-type plasminogen activator (t-PA) and monitored the kinetics of fibrinolysis and changes in ex vivo platelet aggregation responses over time. Both heparin and hirudin enhanced total fibrinolysis in an ex vivo arteriovenous shunt preparation: 82 +/- 2% and 79 +/- 2%, respectively, compared with 51 +/- 8% for t-PA alone (P less than 0.05) and 50 +/- 4% for t-PA plus aspirin (p less than 0.05). Heparin coadministered with t-PA significantly reduced the half-time for clot lysis compared with t-PA alone (p less than 0.05), whereas hirudin coadministered with t-PA significantly reduced the half-time for clot lysis compared with that for t-PA alone, t-PA plus aspirin, and t-PA plus heparin (5.5 +/- 0.6 versus 12.1 +/- 2.0 versus 12.6 +/- 2.2 versus 10.0 +/- 0.8 minutes, respectively; p less than 0.05). Both heparin and hirudin prevented the increase in ADP-induced platelet aggregation normally seen with t-PA alone (p less than 0.01 by t test; p less than 0.05 by two-way analysis of variance). These data demonstrate that selective, antithrombin III-independent thrombin inhibitors can enhance the efficacy of thrombolysis by modulating the dynamics of the process and preventing platelet activation associated with plasminogen activator therapy.

Animals↗

Ubiquinone and urease distribution in Taphrina and Symbiotaphrina.

Identifications of ubiquinone isoprenologues are presented for isolates identified with six species of Taphrina and for isolates of the two species of Symbiotaphrina. All had Q-10 as the major ubiquinone system. The inclusion of T. populina and S. buchneri, the respective type species, establishes this as the value for these genera. Both species of Symbiotaphrina were urease positive even though, according to the literature, they are unable to utilize urea as a sole nitrogen source. The urease results for the Taphrina isolates were mixed.

Ascomycota↗

A note on Wallemia sebi.

A review of the available information on the monotypic genus Wallemia supports the interpretation that W. sebi is probably a basidiomycete and may be a teleomorph. It has dolipore/parenthesome septa similar to those found in the suborder Tremellineae, except that the associated parenthesome vesicles are very small and composed of a single membrane. A conjectural interpretation is made that the spore chains, which are composed of repeating sets of four, are meiospores generated from a permanently diploid mother cell that divides repeatedly to generate meiocyte daughter cells.

Basidiomycota↗

Seizures following oral lidocaine for esophageal anesthesia.

Lidocaine is absorbed from mucous membranes of the oropharynx, gastrointestinal tract, and tracheobronchial tree. First-pass hepatic metabolism of the drug greatly reduces the amount reaching the general systemic circulation in the normal individual. In patients whose hepatic metabolism is reduced by disease or drugs, or in whom liver blood flow is reduced, this first-pass effect is decreased and lidocaine concentrations may be higher than those produced by the same dose in normal patients. We report an elderly man taking cimetidine with congestive heart failure in whom the accidental ingestion of lidocaine solution for esophageal anesthesia was followed by seizures and elevated serum lidocaine concentrations.

Aged↗

Septal ultrastructure in Sirobasidium magnum and its taxonomic implications.

The parenthesomes of Sirobasidium magnum (Sirobasidiaceae) are composed of arrays of ampulliform vesicles from whose bases microfibrils connect to bands of striated material in the dolipore orifices. This septal morphology and the associated character of a yeast haplophase are comparable to that found in species of the Tremellaceae and Filobasidiaceae. The similarity of these basic characteristics in these three families supports their separation into the suborder Tremellineae (species of the Tremellales with regular dolipore/parenthesome septa and mycelial monokaryons are grouped in the suborder Exidiineae).

Basidiomycota↗