ISSN:0004-945X    

DOI:10.1038/icb.1986.53

出版商:Nature Publishing Group    

年代:1986

数据来源: WILEY

摘要:

SummaryThe present study was undertaken in order to compare simultaneously the semi‐automated leucocyte adherence inhibition (SALAI) assay with the two‐stage macrophage migration inhibition (MMI) assay in patients with colorectal disease. Eighty‐six patients were assayed simultaneously in the MMI assay and the SALAI assays using patients' leucocytes and 83 patients were assayed simultaneously in the MMI assay and the SALAI assay using patients' serum. The SALAI assay using patients' leucocytes was more sensitive (70% vs 40%) and more specific (87% vs 73.3%) than the MMI assay. The SALAI assay was simple to perform, allowed many replicate samples and was more specific and sensitive in relation to the detection of colorectal cancer than other more commonly advocated tests. It may be useful as a screening test for colorectal cancer and it is suggested that further studies should be undertaken in this area.

ISSN:0004-945X    

DOI:10.1038/icb.1986.54

出版商:Nature Publishing Group    

年代:1986

数据来源: WILEY

摘要:

SummaryUptake and metabolism of3H‐noradrenaline 0·18 μmol/l was examined in rabbit gingival slices and ear artery segments. The tissues were ineubated with the3H‐amine for 30 min.The artery accumulated approximately ten times more of the3H‐amine and generated four times more3H‐metabolites than the gingiva.In both tissues, chronic sympathetic denervation resulted in marked decreases in3H‐noradrenaline accumulation and deamination., An inhibitor of sympathetic neuronal uptake, cocaine 30 μmol/l, strongly inhibited the firmly‐bound component of3H‐noradrenaline accumulation by the tissues and strongly decreased the accumulation of deaminated metabolites in the incubating medium.It is concluded that the sympathetic nerve terminals play an important role in the accumulation and deamination of noradrenaline in the gingiva and in the artery.Chronic sympathetic denervation resulted in increased3H‐normetanephrine (NMN) formation by the gingiva and the artery, indicating that in both tissues the noradrenaline was O‐methylated at sites extraneuronal to the sympathetic nerves.Differences between the effects of cocaine in the gingiva and artery, with respect to3H‐NMN accumulation in the incubating medium, are interpreted as evidence that in the gingiva, but not in the artery, cocaine inhibits extraneuronal O‐methyiation, as well as neuronal uptake, of noradrenaline.

ISSN:0004-945X    

DOI:10.1038/icb.1986.55

出版商:Nature Publishing Group    

年代:1986

数据来源: WILEY

摘要:

SummaryThe uptake (total radioactivity in intact cells) and incorporation (radioactivity bound to acid‐precipitable material) of14C‐chlorpromazine (CPZ) and14C‐thiouracil (TU) were studied using a library of 3 human fibroblast strains and 13 tumour cell lines. In contrast to previous studies using rodent melanomasin vivo, the melanoma lines, including lines with high tyrosinase and melanin contents, did not take up more CPZ and TU than non‐melanoma cells (fibroblasts, HeLa cells). Incorporation of CPZ was also broadly similar in all cell types studied. TU was selectively incorporated into the melanoma line having a high tyrosinase and melanin content but not into lines with high tyrosinase activity and low melanin content. While supporting the possibility of selective therapy for heavily‐pigmented melanomas using labelled TU derivatives, these results suggest that the action of potentially melanoma‐affined compounds should be further evaluated in human cells. Unlabelled CPZ or TU was not selectively toxic to melanoma cells. Unexpectedly, methylation‐sensitive tumour cells (Mer‐phenotype) were highly resistant to TU, thus providing a new experimental tool for understanding the genesis of this phenotypein vivo.

ISSN:0004-945X    

DOI:10.1038/icb.1986.56

出版商:Nature Publishing Group    

年代:1986

数据来源: WILEY

摘要:

SummaryFive groups of male rhesus monkeys, Gp. I–sham‐vasectomized stock diet‐fed (SVS), Gp. II–vasectomized stock diet‐fed (VS), Gp. III–sham‐vasectomized atherogenic diet‐fed (SVA), Gp. IV–vasectomized atherogenic diet‐fed (VA) and Gp. V–atherogenic diet‐fed vasectomized monkeys (AV) were observed for a period of 1½ years. Vasectomy per se had no effect on the level of serum or tissue lipids either alone or in combination with atherogenic diet feeding. Following vasectomy the involvement of aorta by fatty lesions was significantly increased and this occurred in animals of all four experimental groups when compared with the control animals. The maximum increase was noted in group IV. Again, there was a significant increase in the frequency of aortic plaques in groups II, III and IV while it was increased in coronary arteries of all the experimental animals (Gps. II, III, IV and V). Group IV monkeys showed higher frequency of plaques as compared to group V animals. Although the plaque height was increased in all the vessels of the experimental animals, significant differences were observed only in the coronary arteries of group II monkeys and in intra‐cranial cerebral vessels of group III animals. This study shows that vasectomy per se tends to increase atherosclerosis in rhesus monkeys.

ISSN:0004-945X    

DOI:10.1038/icb.1986.57

出版商:Nature Publishing Group    

年代:1986

数据来源: WILEY

摘要:

In extending the scope of our previous analyses of tiie functions that mammalian cells engender to recombine elements of genetic information (Upcroft, Carter and Kidson, 1980a and b), I describe the capacity of cells to recognise differentially combinations of open‐ended and closed molecules. The frequency of successful recombination, as assayed by the generation of viable SV40 genomes from appropriate substrates, was shown to decrease with the loss of free termini capable of invasion of an homologous DNA duplex and to be influenced by the presence of non‐homologous flanking sequences, the length of homology and whether the sequence was internal or terminal. The effect of stabilisation with long homologous regions on recombination over short homologous regions and inter‐ versus intramolecular DNA sequence homologies was also investigated.

ISSN:0004-945X    

DOI:10.1038/icb.1986.58

出版商:Nature Publishing Group    

年代:1986

数据来源: WILEY

摘要:

SummaryAs part of a project to study the effect of copper deficiency (CD) on bone development in young dogs, the composition and metabolism of proteoglycans (PGs) and extractability of collagens in the epiphyseal growth plate cartilage (EGPC) and articular cartilages (AC) were investigated. Copper deficiency was induced by feeding ammonium tetra‐thiomolybdate (TTM) a copper antagonist. The collagen of cartilages from TTM‐treated animals was significantly more soluble in 0‐5 M saline than control tissues. While no distinction between TTM‐treated and control cartilages was evident in terms of PG content or extractability under associative (0‐5 M‐GuHCl) or dissociative (4‐0 M‐GuHCl) conditions, the sedimentation behaviour of the PG aggregates following CsCl density gradient ultracentrifugation suggested less polydispersity of PGs in preparations from the TTM‐treated animals. Moreover, analysis of the PG monomers from EGPC of TTM animals showed galactosamine/glucosamine ratios higher than control preparations, suggesting a reduced keratan sulphate content in these preparations. Organ culture of EGPC showed a significant reduction in the incorporation of35S into PGs and of3H‐thymidine into DNA in the tissues of TTM‐treated animals relative to controls. From these findings we deduce that the catabolism of PGs and the extent of collagen cross‐linking in EGPC of TTM‐treated animals may be reduced relative to age‐matched control tissues.

ISSN:0004-945X    

DOI:10.1038/icb.1986.59

出版商:Nature Publishing Group    

年代:1986

数据来源: WILEY

摘要:

SummaryThe study included 138A. sobriaand 182A. hydrophilaisolated in Perth from samples of diarrhoeal or non‐diarrhoeal faeces or from domestic water. Strains were grouped i n relation to agglutination of human, horse, rat and guinea pig erythrocytes and the effect of sugars on haemagglutination. Agglutination of red cells of all four species (primary group 1) was most commonly associated withA. sobria, particularly those strains isolated from faeces of patients with diarrhoea. MostA. hydrophilaassociated with diarrhoea also belonged to group 1 butA. hydrophilafrom non‐diarrhoeal stools or from water most commonly agglutinated human and guinea pig cells but not horse erythrocytes (primary groups 2 and 3). Fucose‐resistant haemagglutination (FRHA) of strains in primary group 1 occurred with about 68% of the strains ofA. sobriaassociated with diarrhoea. Mannose‐resistant haemagglutination (MRHA) was limited to 29% of strains ofA. sobriaassociated with diarrhoea. The predominance of primary group 1 among strains ofAeromonasspp. associated with diarrhoea and the proportion of these strains showing FRHA suggest that haemagglutination of cells from human, horse, rat and guinea pig, particularly if fucose‐resistant, should be considered in a search for characteristics, which possibly contribute to virulence ofAeromonasspp.

ISSN:0004-945X    

DOI:10.1038/icb.1986.60

出版商:Nature Publishing Group    

年代:1986

数据来源: WILEY

摘要:

SummaryThe genetic relatedness of ten Murray Valley encephalitis virus (MVE) isolates from Australia has been examined by comparing Haelll and Taql restriction digest profiles of cDNA to virion RNA. The isolates were from the Murray Valley region of south‐eastern Australia and from the Ord River region of Western Australia and spanned a period of 23 years (1951‐1974). The isolates generated closely similar restriction digest profiles. The extent of similarity suggested that the level of nucleotide sequence divergence between any pair of Australian MVE isolates is probably around 1%. The genetic homogeneity of the MVE isolates contrasts with results obtained for Ross River virus, an alphavirus, using an identical methodological approach; we propose that this difference results from the important role of birds in the life cycle of MVE.Four MVE isolates from three fatal human cases showed small genetic differences on from the other. These isolates did not have a common restriction digest profile which distinguished them from strains obtained from other sources (e.g., from mosquitoes or a heron) The data do not support the view that clinical cases of MVE infection in humans are to a particular strain of virus although this has not been rigorously excluded.The two available MVE isolates from Papua New Guinea (PNG) were from the Sepik and Port Moresby regions. They generated Haelll and Taql restriction digest profiles which were different both from each other and from those of the Australian type. Genetic divergence between the two PNG isolates was estimated to be ≈ 6%; divergence between either of PNG isolates and the Australian type was>6%. Our data suggest that the evolution of MVE i n Australia and PNG has proceeded independently and that circulating Australian MVE strains are not systematically re‐seeded from regions of endemicity in PNG.Studies on the relatedness of MVE and two close antigenic relatives, Japanese encephalitis virus (JE) and Alfuy virus (ALF), showed that the genetic relatedness between any isolate and JE or ALF is less than that between the most divergent of the MVE isolates, including those from Papua New Guinea.Some epidemiologieal implications of the results are discussed.

ISSN:0004-945X    

DOI:10.1038/icb.1986.61

出版商:Nature Publishing Group    

年代:1986

数据来源: WILEY

摘要:

SummaryClinical cases of Murray Valley Encephalitis in southeast Australia have tended to occur in summer and autumn following extended periods of above average rainfall over most of eastern and northern Australia. The Southern Oscillation, an important mode of climatic fluctuations over the Indian and Pacific Oceans, is closely related to eastern and northern Australian rainfall. The Southern Oscillation has been used previously to develop methods for predicting rainfall fluctuations over Australia and their biological and economic impacts. The relationship, therefore, between the Southern Oscillation and Murray Valley Encephalitis in southeast Australia was examined. Darwin atmospheric pressure, an index of the Southern Oscillation, was found to be well below average during the autumn, winter and spring preceding the occurrence of Murray Valley Encephalitis. It is suggested that this relationship can be used to provide a simple, objective early warning system.

ISSN:0004-945X    

DOI:10.1038/icb.1986.62

出版商:Nature Publishing Group    

年代:1986

数据来源: WILEY