Some Holocene pollen diagrams from Greece

Pollen diagrams have been obtained from three places in Greece. The one from Limni Kopais in southern mainland Greece covers the last part of the Würm glaciation and most of the Holocene and shows that at the end of the Würm the developing oak woodland responded to a climatic oscillation, comparable with the Allerød oscillation in northwest Europe, and was later seriously reduced during Final Neolithic times. A diagram from the uppermost peats of Tenaghi Philippon shows that the area was forested until at least the time of Christ and another from Gravouna, further east, which covers the last two thousand years or so, shows the change from oak forest to the present open shiblyak vegetation of the region. Where possible, correlations have been made with pollen zones of other authors who have published diagrams from the country.     

Estimation and fractionation of the essentially unbranched (amylose) and branched (amylopectin) components of starches with concanavalin A

Conditions have been devised for the quantitative precipitation of the branched fraction in starches by concanavalin A and the enzymic estimation of the - -glucan in this and the soluble components. For some starches, such as those from cereal and high-amylose pea seeds, the percentage of branched fraction determined by this procedure was higher than that calculated by deducting from one hundred the apparent amylose content as measured by potentiometric iodine titration, suggesting a method for estimating the content of material having an atypical structure in the whole starch. The procedure has been adapted to provide a preparative method of separating amylose and amylopectin fractions. It efficiently separated these in starches that cannot be fully fractionated by complexing with 1-butanol, such as those from high-amylose pea seeds and tobacco leaves.     

Development of sucrose preference in rabbit pups

Taste preference behavior in developing rabbit pups was examinedat 2–4 days, 6–8 days and 14–16 days postnatally.0.3 M sucrose and distilled water were presented alternatelyat 2 min. intervals, and volumes ingested were recorded. Sweetpreferences were not expressed until late in the second postnatalweek. Since it is known that rabbit pups exhibit distinctivefacial displays to different taste stimuli at birth (Ganchrowet al., 1979) the delay in the expression of sweet preferencewas postulated to be related to the postnatal maturation ofneural processes central to peripheral and brainstem gustatorycoordinating mechanisms.     

THE APPEARANCE OF REGIONAL VARIATIONS IN METABOLISM AT A CRITICAL LEVEL OF DIFFUSE CEREBRAL OLIGEMIA

Increased intracranial pressure was used to produce graded cerebral oligemia in the rabbit. When cerebral perfusion pressure (CPP) was 40 Torr or above, oligemia was not severe enough to cause a decrease in ATP. When CPP was 20 Torr or below, a rapid depletion of ATP occurred. When CPP equalled 30 Torr, animals were distributed at the two extremes, with pronounced diminution of ATP correlating with loss of electrical activity and with increased NADH tissue fluorescence. In addition this critical stage of oligemia was marked by the appearance of regional variations in metabolism. Furthermore, ischemic regions could be visualized in sections of frozen brain by virtue of increased NADH fluorescence.     

Cellulase Facilitated Squash Preparations of Vicia Faba Chromosomes for Quinacrine Fluorescent Staining

This paper is partially based on work performed under contract with the U. S. Atomic Energy Commission at The University of Rochester Atomic Energy Project and has bcen assigned Report No. UR-3490-238, and has also been partially supported by Grant USPHS GM0933.     

S-adenosylmethionine decarboxylase from Leishmania donovani. Molecular, genetic, and biochemical characterization of null mutants and overproducers.

The polyamine biosynthetic enzyme, S-adenosylmethionine decarboxylase (ADOMETDC) has been advanced as a potential target for antiparasitic chemotherapy. To investigate the importance of this protein in a model parasite, the gene encoding ADOMETDC has been cloned and sequenced from Leishmania donovani. The Delta adometdc null mutants were created in the insect vector form of the parasite by double targeted gene replacement. The Delta adometdc strains were incapable of growth in medium without polyamines; however, auxotrophy could be rescued by spermidine but not by putrescine, spermine, or methylthioadenosine. Incubation of Delta adometdc parasites in medium lacking polyamines resulted in a drastic increase of putrescine and glutathione levels with a concomitant decrease in the amounts of spermidine and the spermidine-containing thiol trypanothione. Parasites transfected with an episomal ADOMETDC construct were created in both wild type and Delta adometdc parasites. ADOMETDC overexpression abrogated polyamine auxotrophy in the Delta adometdc L. donovani. In addition, ADOMETDC overproduction in wild type parasites alleviated the toxic effects of 5'-(((Z)-4-amino-2-butenyl)methylamino)-5'-deoxyadenosine (MDL 73811), but not pentamidine, berenil, or methylglyoxyl bis(guanylhydrazone), all inhibitors of ADOMETDC activities in vitro. The molecular, biochemical, and genetic characterization of ADOMETDC establishes that it is essential in L. donovani promastigotes and a potential target for therapeutic validation.     

Status of the search for a major genetic locus for affective disorder in the Old Order Amish

Summary We have resumed the search for an autosomal linkage with affective disorder in the Old Order Amish and report the pairwise linkage results after screening 185 marked loci. No positive evidence of genetic linkage was found, and we estimate that roughly 23% of the autosomal genome has been excluded from linkage.