Location of parathyroid adenomas by thallium-201 and technetium-99m subtraction scanning.

Solitary parathyroid adenomas were correctly located before surgery in 20 out of 21 cases by using 201mT1 and 99mTc in a subtraction technique. The technique was not useful in identifying hyperplastic parathyroid glands. The technique is recommended as a useful procedure before surgery for primary hyperparathyroidism.     

The mouse has a Polycomb-like chromobox gene.

The Drosophila gene Polycomb (Pc) has been implicated in the clonal inheritance of determined states and is a trans-regulator of the Antennapedia-like homeobox genes. Pc shares a region of homology (the chromobox) with the Drosophila gene Heterochromatin Protein 1 (HP1), a component of heterochromatin. The Pc chromobox has been used to isolate a mouse chromobox gene, M33, which encodes a predicted 519 amino acid protein. The M33 chromodomain is more similar to that in the Pc protein, than that in the HP1 protein. In addition to the chromodomain, the M33 and Pc proteins also share a region of homology at their C termini. The temporal and spatial expression patterns of M33 have been studied by in situ hybridization and northern analysis. During the final 10 days of embryonic development, M33 expression mirrors that of the cell-cycle-specific cyclin B gene. It is therefore suggested that the rate of cellular proliferation controls M33 expression. From comparisons of the characteristics of M33 with those of Pc it is proposed that M33 is a Pc-like chromobox gene. The roles of M33 and Pc in models of cellular memory are examined and implications of the memory models addressed.     

Uptake and metabolism of vitamins e and k by pea stem sections

The uptake of α-tocopherol and vitamin K₁ by pea stem sections is described. Vitamin K₁ appears to be stable within the plant tissue and is found distributed in all particulate cell fractions following uptake. Only a small proportion of the tocopherol taken up is recoverable and the majority of the compound appears to undergo catabolism.

The oxidation of tocopherols by a cell-free system is described. This system requires oxygen and appears to involve enzyme activity but does not appear to be linked with the action of lipoxidase.

     

PCR detection of Anaplasma platys in blood and tissue of dogs during acute phase of experimental infection

Four dogs were experimentally infected with Anaplasma platys to determine changes in real-time TaqMan PCR detection in blood and tissue, microscopically detectable parasitemia, and platelet concentrations during the first 28 days of infection. Buffy-coat blood cells were PCR positive for A. platys DNA at 4 days after inoculation and remained positive in all dogs until day 14. Marked thrombocytopenia and low parasitemia occurred in dogs during that initial period. During 17 and 28 days post-inoculation, the PCR results on buffy-coat blood cells were intermittently negative in each dog with marked thrombocytopenia and no microscopic evidence of parasitemia. Bone marrow and splenic aspirates collected from the A. platys-infected dogs were tested by real-time TaqMan PCR. Two dogs were PCR positive in spleen and marrow at 28 days post-inoculation, when PCR results for buffy-coat blood cells were negative. Spleen and/or bone marrow samples should be considered as additional samples for PCR testing of dogs, particularly when blood samples are PCR negative during the acute phase of A. platys infection.     

Bacterial metabolism of 4-chloro-2-methylphenoxyacetate. Formation of glyoxylate by side-chain cleavage

Crude extracts of Pseudomonas sp. grown on 4-chloro-2-methylphenoxyacetate as sole source of carbon were shown to oxidize 4-chloro-2-methylphenoxyacetate to 5-chloro-o-cresol and glyoxylate. A labelled 2,4-dinitrophenylhydrazone was isolated from an incubation mixture in which 4-chloro-2-methylphenoxy[carboxy-¹⁴C]acetate was used. The hydrazone was shown to behave identically on thin-layer chromatograms with the authentic 2,4-dinitrophenylhydrazone of glyoxylate. Radioactivity assay showed that 82% of the side chain of 4-chloro-2-methylphenoxyacetate was recovered as glyoxylate.