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11.
Rudy Van Cauwenbergh Harry Robberecht Veerle Van Vlaslaer Hendrik Deelstra 《Journal of trace elements in medicine and biology》2004,18(1):99-112
Graphite furnace atomic absorption spectrometry, after improved matrix modification and using Zeeman background correction, was used to measure the serum selenium content of healthy adults living in the Antwerp region (Belgium). The mean serum concentration of 13 men and 13 women, sampled once a month during 1 year, was 84.3 +/- 9.4ng/ml with a broad range of 51.4-121.7 ng/ml. The intra-individual variation was remarkably high. Recent literature on selenium concentrations is reviewed and values are tabulated, with limitation to healthy adults and European countries. The mean serum selenium concentration measured corresponded well to older literature data for Belgium. The obtained values were found to be in the medium range compared with the literature data for other European countries. 相似文献
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Summary A basic procedure was developed to produce a tempe-like product using the mouldRhizopus
oligosporus and black common beans (Phaseolus
vulgaris) as substrate. The initial pH of the substrate was 5.8, and fermentation was conducted at 37°C with a relative humidity of 70% for 72 hrs. Levels of soluble solids and soluble protein increased dramatically as a result of fermentation. Some changes were as well observed in fatty acid contents of fermented samples. It was concluded that the common bean used was an acceptable substrate for preparing this product. 相似文献
14.
Harry J. Klee Yvonne M. Muskopf Charles S. Gasser 《Molecular & general genetics : MGG》1987,210(3):437-442
Summary 5-enolpyruvylshikimate-3-phosphate synthase (EPSPs), the target of the herbicide glyphosate, catalyzes an essential step in the shikimate pathway common to aromatic amino acid biosynthesis. We have cloned an EPSP synthase gene from Arabidopsis thaliana by hybridization with a petunia cDNA probe. The Arabidopsis gene is highly homologous to the petunia gene within the mature enzyme but is only 23% homologous in the chloroplast transit peptide portion. The Arabidopsis gene contains seven introns in exactly the same positions as those in the petunia gene. The introns are, however, significantly smaller in the Arabidopsis gene. This reduction accounts for the significantly smaller size of the gene as compared to the petunia gene. We have fused the gene to the cauliflower mosaic virus 35 S promoter and reintroduced the chimeric gene into Arabidopsis. The resultant overproduction of EPSPs leads to glyphosate tolerance in transformed callus and plants. 相似文献
15.
Harry J. Klee Maria B. Hayford Stephen G. Rogers 《Molecular & general genetics : MGG》1987,210(2):282-287
Summary Cloning of genes by transformation with genomic banks and rescue of a phenotype has been extensively used in bacterial systems. This approach has not been possible in plant systems because of the large genome sizes and poor transformation frequencies of most plant species. Recent advances in plant transformation permit the generation of large numbers of transformants in petunia. We have used this system to rescue a model gene encoding resistance to kanamycin by shotgun cloning. The gene encoding neomycin phosphotransferase (NPTII) was introduced into the genome of Arabidopsis thaliana by Agrobacterium tumefaciens-mediated transformation. A genomic bank of DNA from this tissue was constructed in a cosmid vector containing features which would allow its use in plant transformation. The unselected genomic bank was mobilized from Escherichia coli to A. tumefaciens and used to retransform petunia leaf discs. The rescued gene was identified by its ability to confer a kanamycin-resistant phenotype in petunia tissue. The presence of the NPTII gene was confirmed by nopaline assay and Southern blot analysis. This experiment demonstrates the feasibility of gene rescue, in certain circumstances, in plants. 相似文献
16.
Axonal Transport Characteristics of Gangliosides in Sensory Axons of Rat Sciatic Nerve 总被引:2,自引:2,他引:0
G. Jean Harry Jeffry F. Goodrum Arrel D. Toews† Pierre Morell† 《Journal of neurochemistry》1987,48(5):1529-1536
The distribution of axonally transported gangliosides and glycoproteins along the sciatic nerve was examined from 3 h to 4 weeks following injection of[3H]glucosamine into the fifth lumbar dorsal root ganglion of adult rats. Incorporation of labeled precursor into these glycoconjugates reached a maximal level in the ganglion within 6 h. Outflow patterns of radioactivity for glycoproteins showed a well-defined crest with a transport rate of approximately 330 mm/day. In contrast, the crest of transported gangliosides was continuously attenuated, implying a significant deposition along the axon, and an alternative method of calculating velocity was required. Analysis of accumulation of labeled material at double ligatures demonstrated both anterograde and retrograde transport of glycoproteins and gangliosides and allowed for the calculation of an anterograde transport rate of about 270 mm/day for each. Additional evidence of ganglioside transport is provided in that the TLC pattern of transported radioactive gangliosides accumulating at a ligature is significantly different from the pattern seen in the dorsal root ganglion or following intraneural administration of the labeled precursor. These data indicate that gangliosides are transported at the same rapid rate as glycoproteins but are subject to a more extensive exchange with stationary material than are glycoproteins. 相似文献
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Harry Holthöfer M.D. Ph.D. Bradley A. Schulte Samuel S. Spicer 《Cell and tissue research》1987,249(3):481-485
Summary To identify precisely the structural and functional cell type in the collecting duct of the rat kidney expressing binding sites for Dolichos biflorus agglutinin (DBA), we stained serial paraffin sections of kidney with horseradish peroxidase-labeled DBA and with immunocytochemical methods for localizing (Na++K+)-ATPase and carbonic anhydrase II (CA II), enzymes found preferentially in principal and intercalated cells, respectively. Most principal cells expressing a strong basolateral staining for (Na+ + K+)-ATPase showed binding sites for DBA at their luminal surfaces. However, a minority of cells rich in CA II and showing morphologic characteristics of intercalated cells also expressed DBA binding sites at their luminal surface and apical cytoplasm. These data suggest that DBA cytochemistrycan provide a useful tool for studying the functional polarity of the main cell types of the collecting duct of the rat kidney. 相似文献
19.
Isolation and culture of cells derived from human cerebral microvessels 总被引:10,自引:0,他引:10
Harry V. Vinters Susan Reave Penny Costello John P. Girvin Steven A. Moore 《Cell and tissue research》1987,249(3):657-667
Summary Microvessels were isolated from non-neoplastic human cerebral cortical fragments resected for treatment of intractable seizure disorder. The microvessels were incubated in modified Lewis medium with 20 or 30% fetal bovine serum. Within 1–2 weeks, two cell populations emerged from the isolates. One type of cells had polygonal morphology, showed density-dependent contact inhibition at confluence in vitro, showed lectin-binding characteristics of endothelium (but only moderate positivity for factor VIII antigen), demonstrated induction of -glutamyl trans-peptidase when exposed to astrocyte-conditioned media, and responded to insulin by a pronounced increase in DNA synthesis. The other variety of cells grew in vitro more slowly in irregular strands separated by clear zones, showed ultrastructural features of smooth muscle, and isoelectric focusing of cell proteins revealed the presence of smooth-musclespecific -isoactin. Both types of cells could be serially subcultured. The ability to isolate and grow the two cell types, tentatively identified as human cerebral microvascular endothelium and smooth muscle, may facilitate studies of human blood-brain barrier function as well as the pathogenesis of cerebral microangiopathies unique to the human brain.Funded by Canadian Heart Foundation, Heart and Stroke Foundation of Ontario and UCLA Biomedical Research Support Grant 相似文献
20.
Summary C-band polymorphisms of chromosome 1 can be quantified by Ce bands visualized using oblique epi-illumination. In this paper the polymorphic region of chromosome 9, including variants such as 9qh+, inversions, and translocations, was analyzed in a total of 1860 chromosomes from 20 individuals and 8 fetuses. In this sample we found between zero and five Ce bands on 9q and between zero and four Ce bands on 9p with a maximum of five Ce bands per chromosome. On the basis of these observations at least 19 different polymorphic patterns can be expected theoretically, 15 of which were observed in our sample. Among these, five polymorphic Ce-band classes were distinguishable by the method presented. Considering both homologues, 52=25 quantitatively discernible chromosome 9 pairs may exist. 相似文献