RESUMEN

A total of 86 species of bryophytes, lichens and vascular plants were collected from New Zealand's subantarctic Campbell and Auckland Islands, including 18 subantarctic endemic species. Extracts of these species have been screened for antimicrobial activity and toxicity towards a P388 cell line. Of the main taxonomic groups collected, the proportion of extracts with some biological activity was highest for liverworts (25/29), intermediate for flowering plants (17/26) and lowest for mosses and horn worts (4/22). Extracts of six species showed repeatable, high biological activity warranting further investigation. The cytotoxicity of Ranunculus pinguis was due to the presence of ranunculin.

RESUMEN

The ceroid-lipofuscinoses are inherited lysosomal storage diseases of children and animals characterised by a fluorescent lipopigment stored in a variety of tissues. Defects in lipid metabolism or the control of lipid peroxidation have been postulated to explain their pathogenesis but the underlying biochemical defect is still unknown. In the present study lipopigment was isolated from liver, kidney, pancreas and brain of sheep affected with ceroid-lipofuscinosis. Approximately two-thirds of the lipopigment mass was protein. Sodium dodecyl sulphate polyacrylamide gel electrophoresis showed a major polypeptide band of Mr 14,800, heterogeneous polypeptides between 5,000-9,000 Mr and a major band of Mr 3,500. These were not normal lysosomal proteins. I125 radiolabeling studies indicated that they were 47% of the pancreatic lipopigment mass, the 3,500 Mr polypeptides alone accounting for 26%. Lipopigment polypeptides were not subunits of a larger protein held together by disulphide bonds. The presence of the 3,500 Mr proteins in whole affected tissue homogenates distinguished them from homogenates of normal tissues. Lipopigment phospholipids were the same species as normal lysosomal phospholipids, including bis (monoacylglycero) phosphate, a lysosomal marker. Similarly the neutral lipids, notably dolichol, ubiquinone and dolichyl esters were typical of those in lysosomal membranes. Lipopigments contained 1-1.7% metals. Analyses of them indicated a functional lysosomal origin for the lipopigment. It was concluded that low Mr proteins are specifically stored in ovine ceroid-lipofuscinosis and that this disease is a lysosomal proteinosis.

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The association of virus infection with an acute attack of asthma in 204 children admitted to hospital over a one year period was studied. Two comparative groups were assessed in parallel. Nineteen percent of acute asthma attacks were associated with viral infection. The range of the viral agents identified was comparable to that of a group of nonasthmatic children with an acute respiratory infection. These findings were, however, significantly different from an asthmatic group without acute illness.

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A map of cleavage sites for the restriction endonucleases EcoRI, HindIII, BamHI, HpaI, and KpnI for a New Zealand strain of orf virus (NZ2) DNA has been deduced. Also, the entire genome, apart from approximately 0.1 kbp at each end, has been cloned into various vectors. The genome is 139 kbp in length and, in common with other poxviruses, has inverted terminal repetitions and crosslinked ends.

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The genomes of several orf virus strains were analyzed with the restriction endonucleases EcoRI, HindIII, BamHI, and KpnI, and cleavage site maps were deduced. In general, the right half of the genome showed conservation of restriction sites compared with the left half. Variations in size of up to 0.5 kbp were found within an inverted terminal repetition, and a 1-kbp deletion was detected in some strains in a subterminal fragment at the left end. A region of approximately 20 kbp, some 12 kbp in from the left end, showed the greatest cleavage site variability although there was no evidence of large deletions in this region. A 1.55-kbp cloned DNA fragment from the internal variable region of NZ2 failed to hybridize to the DNA from three other strains. A fragment in the variable region of strain NZ7 was cloned and compared by hybridization and restriction endonuclease analysis with cloned NZ2 fragments from the same region. The region of nonhomology extended for at least 2.75 kbp. It is suggested that this internal variable region may provide sites for the insertion of foreign genes.

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Previous studies on the lipopigment from the livers of sheep affected with ceroid lipofuscinosis showed that the disease does not involve a defect in lipid metabolism or abnormal lipid peroxidation and that most of the lipopigment was proteinaceous. In this study, lipopigment was isolated from liver, kidney, pancreas, and brain of affected sheep without the use of proteolytic enzymes. Lipopigment from all tissues was two-thirds protein. Modified silver staining after sodium dodecyl sulfate-polyacrylamide gel electrophoresis showed a major band of Mr = 14,800, heterogeneous material between Mr = 5,000 and 9,000, and a major band of Mr = 3,500. These compounds did not stain for RNA or carbohydrate and were digested by a nuclease-free protease as expected for protein. They are not normal lysosomal proteins. Lipopigment levels of dolichol, ubiquinone, and cholesterol were consistent with the lipopigment being protein-enriched lysosome-derived cytosomes. The presence of the Mr = 3,500 proteins in whole affected tissue homogenates distinguished them from homogenates of normal tissues. It was concluded that low Mr proteins are specifically stored in ovine ceroid lipofuscinosis and that the ceroid lipofuscinoses may result from inherited defects in lysosomal protein catabolism.

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