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Item Metadata only Zellweger syndrome amniocytes - morphological appearance and a simple sedimentation method for prenatal-diagnosis(Springer Nature, 1988) LAZAROW, P.B.; SMALL, G.M.; SANTOS, M.; SHIO, H.; MOSER, A.; MOSER, H.; ESTERMAN, A.; BLACK, V.; DANCIS, J.Zellweger syndrome is the prototype of a growing group of genetic diseases caused by an absence or deficiency of peroxisomes. The defect causes the enzyme catalase to remain in the cytosol instead of being packaged into peroxisomes. This mislocalization can be easily detected by sedimentation analysis. Amniocytes were homogenized and then centrifuged to pellet organelles. Catalase was found to sediment with the peroxisomes in the homogenates of normal cells, but to remain in the supernatant with Zellweger syndrome amniocyte homogenates. This striking difference is unambiguous and reproducible, and provides a simple method for prenatal diagnosis. Moreover, it allows one to differentiate diseases in which peroxisomes are deficient from other peroxisomal diseases in which the organelle is intact, but one enzyme is defective. Electron microscopic observations support the biochemical determinations. Normal amniocytes contain small peroxisomes in which a weak cytochemical reaction for catalase may be demonstrated. Zellweger amniocytes appear to lack these organelles, although some cells have rare structures that might be residual or abnormal peroxisomes.Item Metadata only Determination of the optimal ratio of linoleic acid to α-linolenic acid in infant formulas(Elsevier, 1992) Clark, K.J.; Makrides, M.; Neumann, M.A.; Gibson, R.A.The fatty acid composition of erythrocyte total lipids taken from a group of term infants 10 weeks after being fed a commercial infant formula with a high ratio of linoleic acid (18:2n-6) (LA) to alpha-linolenic acid (18:3n-3) (ALA) (19:1; LA, 14%; ALA, 0.7%; group A, n = 10) was compared with the fatty acid composition of erythrocytes from infants fed formulas that contained LA/ALA ratios reduced by either increasing ALA (4:1; LA, 13%; ALA, 3.3%; group B, n = 11) or decreasing LA (3:1; LA, 3.5%; ALA, 1.1%; group C, n = 8). Results were compared with those in an age-controlled group (n = 9) of breast-fed infants. Decreasing the LA/ALA ratio increased n-3 C20 and C22 fatty acid incorporation (formula B = 8.98% +/- 0.65%; formula C = 9.30% +/- 0.95%) relative to formula A (5.97% +/- 0.76%; p less than 0.05). Although docosahexaenoic acid (22:6n-3) (DHA) incorporation was highest in infants fed formulas B and C (4.78% +/- 0.45% and 4.48% +/- 0.49%, respectively) relative to formula A (3.47% +/- 0.46%; p less than 0.05), it did not reach levels found in breast-fed infants (6.55% +/- 1.23%; p less than 0.05). In addition, levels of arachidonic acid (20:4n-6) (AA) were lower in all formula-fed groups (p less than 0.05) relative to those in breast-fed infants. Based on some equations, it is predicted that AA levels in tissues of infants fed lower LA/ALA ratios would be reduced even further. Because both AA and DHA are probably essential for normal neural development of the infant, formulas with LA/ALA ratios below 4:1 are likely to result in fatty acid profiles notably different from those of breast-fed infants.Item Metadata only Erythrocyte docosahexaenoic acid correlates with the visual response of healthy, term infants(International Pediatric Research Foundation, 1993) Makrides, M.; Simmer, K.; Goggin, M.; Gibson, R.A.Recent studies have reported that formula-fed preterm infants score lower on visual and developmental tests relative to breast-fed preterm infants. This phenomenon has been associated with the presence of docosahexaenoic acid (DHA), an omega-3 fatty acid, in breast milk and its absence from infant formula. To investigate the possibility that DHA status of healthy, term infants is also related to neuronal function of the visual pathway, we studied the erythrocyte fatty acid profiles of 16 infants at 22.3 +/- 3.9 wk of age and related these to maturity of the visual pathway as assessed by visual-evoked potentials. Healthy, term infants fed breast milk had better visual-evoked potential acuity (p < 0.05) and higher DHA levels (p < 0.001) than infants who received infant formula as their major energy source. There was a positive correlation between erythrocyte DHA and visual-evoked potential acuity (p < 0.01). The data are preliminary and the long-term effects as yet unknown. However, our results suggest that there is an urgent need to evaluate the dietary fatty acid supply of formula-fed term infants.Item Metadata only Isolation and characterization of ovine IGFBP-4: protein purification and cDNA sequence(BioScientifica, 1994) CARR, J.M.; GRANT, P.A.; FRANCIS, G.L.; OWENS, J.A.; WALLACE, J.C.; WALTON, P.E.Three different molecular mass forms of IGF-binding proteins (IGFBPs) were purified from ovine plasma by IGF-I affinity chromatography and reverse-phase HPLC: a 46 kDa doublet and 29 kDa and 24 kDa forms. Amino-terminal sequence analysis confirmed that these proteins were ovine (o)IGFBP-3 (46 kDa) and two molecular size variants of oIGFBP-4. oIGFBP-3 and the 29 kDa form of oIGFBP-4 were shown to be N-glycosylated. Isoelectric points were determined to be at approximately pH 6 for oIGFBP-3 and at pH 7 and pH 7.5 for the 29 and 24 kDa forms of oIGFBP-4 respectively. The two different molecular mass variants of oIGFBP-4 had similar IGF-binding properties. Compared with human IGFBP-3 and oIGFBP-3, the two variants of oIGFBP-4 exhibited lower relative binding to amino-terminally modified IGF-I analogues in a competitive IGF-binding assay. The full protein sequence of oIGFBP-4, as deduced from the cDNA sequence, showed a high degree of identity with rat (90%), human (96%) and bovine (98%) IGFBP-4. The cDNA sequence also showed homology over regions of the 3' non-coding sequence, particularly in comparison with bovine IGFBP-4 (96%). Northern analysis of mRNA for oIGFBP-4 indicated a 2.6 kb major transcript and two minor transcripts of approximately 2.1 and 1.8 kb. oIGFBP-4 mRNA transcripts were detected in adult ewe liver > kidney > lung >> heart and also in several fetal tissues, thus suggesting tissue-specific and developmental regulation. The availability of purified oIGFBP-4 and oIGFBP-3 as well as DNA probes for oIGFBP-4 will enable further study of the properties and functions of these proteins, as well as the establishment of specific assays for these IGFBPs.Item Open Access Cytokine receptor expression in human lymphoid tissue: analysis by fluorescence microscopy(Hindawi Publishing Corporation, 1994) Zola, H.; Ridings, J.; Weedon, H.; Fusco, M.; Byard, R.; Macardle, P.A highly-sensitive flourescence method, capable of detecting cytokine receptors present at low concentrations (around I DO molecules per cell) by flow cytometry, was adapted for use on tissue sections. This method was used to examine the expression of several cytokine receptors in lymphoid ti ss ues. lL-2 receptors were distributed broadly, with higher concentrations in T cell areas. lL-1 receptor Type I was detected in T cell areas and in the follicular mantle, and was strongly expressed on vasc ular endothelium. IL-6 receptor was found at very low concentration, both within and outside germinal centres. The gp 130 molecule, which is involved in the functional receptor complex for IL-6 and several other cytokines, was present at higher concentrations, particularly in the germinal centre. Analysis of receptor expression in secondary lymphoid tissue provides evidence bearing on the physiological roles of cytokines, as these tissues contain cells at various stages of physiological activation located in well-defined functional zones.Item Metadata only Paediatric surgery in Cambodia(Australasian Medical Pub. Co., 1995) Dewan, Paddy A.Item Metadata only A region of primer binding variation at the D6S265 locus associated with HLA-A25 and HLA-A26 antigens(Springer-Verlag, 1995) Pyper, Wendy R.; Burt, Michael J.; Powell, Lawrie W.; Webb, Sonja I.; Ades, Lesley Carole; Halliday, June W.; Jazwinska, Elizabeth C.Item Metadata only The Diabetes control and complications trial : Implications for the insulin dependent diabetes(Australasian Medical Pub. Co., 1995) Couper, J.; Jones, T.; Donaghue, K.; Clarke, C.; Thomsett, J.; Silink, M.Item Metadata only Editorial Comment - Congenital obstruction of the male urethra(1995) Dewan, Paddy A.Item Metadata only Bowel management(Griffin Press, 1995) Ford, W.Item Metadata only Polyenoic very-long-chain fatty acids mobilise calcium from a thapsigargin-insensitive pool in human neutrophils. The relationship between Ca++ mobilization and superoxide production induced by long- and very-long fatty acids(PORTLAND PRESS, 1995) Hardy, S.; Robinson, B.; Ferrante, A.; Hii, C.; Johnson, D.; Poulos, A.; Murray, A.Fatty acids with more than 22 carbon atoms (very-long-chain fatty acids; VLCFAs) are normal cellular components that have been implicated in the pathophysiology of a number of peroxisomal disorders. To date, however, essentially nothing is known regarding their biological activities. Ca2+ mobilization is an important intracellular signalling system for a variety of agonists and cell types. Given that several polyunsaturated long-chain fatty acids mobilize intracellular Ca2+ and that we have postulated that the VLCFAs may be involved in signal transduction, we examined whether the tetraenoic VLCFA induced Ca2+ mobilization in human neutrophils. We report that fatty acid-induced intracellular Ca2+ mobilization declined for fatty acid species of more than 20 carbon atoms, but increased again as the carbon chain length approached 30. This Ca2+ mobilization occurred independently of inositol 1,4,5-triphosphate production and protein kinase C translocation and involved both the release of Ca2+ from the intracellular stores and changes to the influx or efflux of the ion. We further observed that triacontatetraenoic acid [30:4(n-6)] mobilized Ca2+ from a thapsigargin-insensitive intracellular pool distinct from the thapsigargin-sensitive pools affected by arachidonic acid [20:4(n - 6)] or N-formyl-L-methionyl-L-leucyl-L-phenylalanine (fMLP). 20:4 (n - 6) induced strong superoxide production (chemiluminescence) which was inhibited by thapsigargin pretreatment. In contrast, fatty acid-induced superoxide production progressively declined as the carbon chain length increased beyond 20-22 carbon atoms. Further studies suggested that the thapsigargin-insensitive Ca2+ mobilization elicited by 30:4 (n - 6) was not related to oxyradical formation, while the thapsigargin-sensitive Ca2+ mobilization induced by 20:4 (n - 6) may be involved in the initiation but not necessarily the maintenance of superoxide production. In conclusion, this is the first report to demonstrate a biological activity for the VLCFA and indicates that 30:4 (n - 6) influences second messenger systems in intact cells that differ from those affected by long-chain fatty acids such as 20:4 (n - 6).Item Metadata only An integrated physical map of human chromosome 16(Nature Publishing, 1995) Doggett, N.; Goodwin, L.; Tesmer, J.; Meincke, L.; Bruce, D.; Clark, L.; Altherr, M.; Ford, A.; Chi, H.C.; Marrone, B.; Longmire, J.; Lane, S.; Whitmore, S.; Lowenstein, N.; Sutherland, G.; Mundt, M.; Knill, E.; Bruno, W.; Macken, C.; Torney, D.; et al.We describe an integrated physical, genetic and cytogenetic map of human chromosome 16 comprising both a low-resolution megaYAC map and a high-resolution cosmid contig/mlnlYAC map, which provides nearly complete coverage of the euchromatic arms of the chromosome. The physical map is anchored to a high-resolution cytogenetic breakpoint map and is Integrated with genetic and gene transcript maps of the chromosome by sequence-tagged sites and clone hybridizations.Item Metadata only Book Review. The good gut cookbook(1995) Moore, D.Item Metadata only Familial triad of anorectal, sacrococcygeal and presacral anomalies which include sacroccygeal teratomas(1995) Crameri, J.; Ford, W.; Morris, L.Item Metadata only Maternal serum screening and prenatal diagnosis for birth defects(University Press, 1995) Suthers, G.; Haan, E.Item Metadata only The Adelaide nutrition study 3. Food sources of nutrients at ages 11, 13 and 15 years(1995) Magarey, A. M.; Boulton, T. J. C.Item Metadata only N-Acetylgalactosamine-6-sulphatase(V.C.H. Publications, 1995) Bielicki, J.; Hopwood, J.Item Metadata only The evolution of the management of bladder exstrophy(1995) Dewan, Paddy A.Item Metadata only Atlanto-axial subluxation in children with seronegative enthesopathy and arthropathy syndrome: 2 case reports and a review of the literature(Journal of Rheumatology Pub. Co., 1995) Foster, H.; Cairns, R.; Burnell, R.; Malleson, P.; Roberton, D.; Tredwell, S.; Petty, R.; Cabral, D.We describe 2 HLA-B27 positive children with seronegative enthesopathy and arthropathy (SEA) syndrome who developed spontaneous (nontraumatic) atlantoaxial subluxation early in their disease course. Neither child had evidence of spinal cord compression but both had progressive atlantoaxial subluxation in spite of conservative treatment. Both underwent elective posterior cervical (C1-C2) fusion.Item Metadata only Outbreak of HUS in Adelaide associated with dry fermented sausage contaminated with VTEC 0111:H-(Istituto Superiore di Sanità, 1995) Goldwater, P.; Bettelheim, K.