Changes in whole tissue biosynthesis of gamma-amino butyric acid (GABA) in basal ganglia of the dystonia (dtAlb) mouse

The mouse mutant dystonia musculorum shows many of the symptoms of of human dystonics. In this study whole tissue samples of mutant striatum and substantia nigra showed almost 50% less γ-amino butyric acid (GABA) biosynthetic capacity than controls of the same inbred strain. Hypothalamic values were unchanged. The defect appears to be one of substrate localization, since both crude extract enzyme activity and the fractional conversion of glutamate to GABA were unaffected by the mutation. When tissue is disrupted, high-affinity synaptosomal uptake to glutamate does not appear to be affected; therefore an endogenous inhibitor of glutamate transport is postulated for the mutant.     

Base-specific ribonucleases potentially involved in heterogeneous nuclear RNA processing and poly(A) metabolism

Polyadenylation and splicing of heterogeneous nuclear RNA, two crucial steps in mRNA processing, are apparently enzymatically mediated processes. This contribution summarizes the properties and the presumed functions of the known poly(A) catabolic enzymes (endoribonuclease IV and V, 2',3'- exoribonuclease ) as well as those of the pyrimidine-specific endoribonucleases associated with snRNP -hnRNP complexes (endoribonuclease VII, acidic pI 4.1 endoribonuclease and poly(U)-specific U1 snRNP -nuclease).     

Cell division in Escherichia coli septation during synchronous growth

Summary The capacity of E. coli B/r to support recombination and complementation between T4am phages during its life cycle has been analyzed in order to get information on the mechanism of cell division. It was found that a decrease in recombinants and complementation events, which is expected at the time of cell compartmentalization coincides with physical cell separation. Therefore, we conclude that the two halves of a dividing cell remain connected until a very late stage of the division period, thus allowing exchange of DNA and protein molecules.When a synchronized culture of E. coli B/r is infected at different cell age with phage T4, the number of surviving cells increases 10 min prior to cell division. At this time the cells are separated into two independent targets for killing by the phage, although there is still free exchange of DNA and proteins within the whole cell. The localized action of murein metabolizing enzymes at the site of subsequent cell division is likely to create a barriere within the cell envelope that prevents the propagation of the phage killing signal.     

Effect of mother plant age on germination and size of seeds and seedlings in the perennial sedge Carex secalina (Cyperaceae)

The performance of seeds and seedlings in relation to the age of the mother plant was studied in Carex secalina. Seeds of this sedge can differ substantially in size. We planted 100 C. secalina individuals from three populations in a common garden and followed them for four years. We found that mean seed mass varied with plant age, but the pattern of variation was population-specific, with only one population showing significant reduction in seed mass with age. Similarly, germination frequency changed with age differently in different populations. The relationship between the age of the mother plant and the height of emerged seedlings did not differ between populations. In spite of the fact that plant size and mean seed mass exhibited similar patterns of variation within populations, there was no correlation between these two variables at the level of individuals. This means that the size of C. secalina tufts does not determine how big the seeds will be. Moreover, there was no relationship between mean seed mass and the height of seedlings. Presumably, factors intrinsic to each plant determine the production of either small or large seeds in a population-specific way.     

Cross-reactivity of SARS-CoV structural protein antibodies against SARS-CoV-2

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The ability of blackcurrant extracts to positively modulate key markers of gastrointestinal function in rats

An animal model was used to assess the effects of orally administered aqueous extract from two commercial health supplement ingredients; First Leaf (FL; composed of blackcurrant extract powder, lactoferrin and lutein and is developed by the Four Leaf Japan Co. Ltd, Japan) and Cassis Anthomix 30 (CAM30; blackcurrant extract powder which is developed by Just the Berries Ltd, New Zealand) on the proliferation of lactobacilli and bifidobacterial species and some undesirable bacteria in the caeca of rats. Gavaging rats with CAM30, FL or inulin three times weekly for 4 weeks resulted in a significant increase in the numbers of bifidobacteria and/or lactobacilli and a significant decrease in the numbers of bacteroides and clostridia. Moreover, rats gavaged with FL, CAM30 and inulin showed 31.5, 18 and 15% reduction in the activity of β-glucuronidase and 26, 30.4 and 18% increment in the activity of β-glucosidase when compared to the control group gavaged with water, respectively. These benefits may make these products good candidates as prebiotic agents. In conclusion, this study has shown that FL and CAM30 can positively modulate key markers of gastrointestinal function in rats.