Plasma homocysteine and glycine are sensitive indices of folate status in a rodent model of folate depletion and repletion

The objectives of the current studies included the characterization of the temporal changes in indices of folate status and amino acid concentrations during both folate depletion and repletion phases. In trial 1, a 6 week folate depletion protocol was employed, using 60 weanling rats assigned to receive an amino acid-defined diet with or without 1 mg/kg folic acid. A 4 week folate depletion period was judged to be optimal on the basis of the development of nadirs in both plasma and hepatic folate stores and elevated (>6-fold relative to folate-adequate controls) concentrations of plasma homocysteine and glycine. In trial 2, 54 weanling rats, previously maintained on a folate-devoid diet for 4 weeks, were assigned to receive 0.25 mg/kg folate as either crystalline folic acid or folate from a folate-enriched egg yolk powder. Both forms of folate supported similar rates of gain, increases in plasma and hepatic folate stores, and reductions in plasma glycine concentrations, whereas the folate in egg yolk powder lowered plasma homocysteine concentrations further than the crystalline folic acid (P < 0.05). These data support the use of both plasma glycine and homocysteine as sensitive response criteria for folate status in a rat bioassay of folate depletion and repletion and establish appropriate temporal end-points for such studies.     

Ersch?pft sich die Forstwirtschft im Nutzen-Kosten-Dergleichen

Ohne Zusammenfassung     

Ein neuer Begriff des Standortsweifers

Ohne ZusammenfassungErschienen in Annales pro experimentis Foresticis, II. Ig., Zagreb 1927. 50 S. stark, mit 18 graphischen Datstellungen und zahlreichen Tabellen (in deutscher Sprache).     

Principles of biological control of soil-borne plant diseases

Unexpected results derived from applications of chemicals to soils led to investigations of the soil biology, discovery of the rhizosphere and eventually to research on mechanisms of biological control. Decisively, chemicals have staved off major disasters in agriculture. In instances of successful monoculture, below ground pathogens appear to be suppressed by an injurious biology, in principle not unlike an injurious host-specific biology which increases with repeated cultivation of the same crop. Crop diversity, nevertheless, is basic to continued successful production agriculture. Decoy hosts which initiate germination of resisting structures may deplete pathogens of energy reserves, and serve to protect the major host. Endogone, which occupies root cortical tissue of most plants, in addition to the traditional mycorrhizal function, may afford protection against invasion by pathogens. Healthy Endogone may be essential to healthy crops.     

Wuchsgesetze von Pinus silvestris

Ohne Zusammenfassung     

Zur Gliederung der forstwirtschaftslehre in Produktions lehre und Vetriebslehre

Ohne Zusammenfassung