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1.
Z. Kato Seiji Fukuda Shunji Tomatsu Hugo Vega Teruo Yasunaga Atsushi Yamagishi Naoto Yamada A. Valencia Luis Alejandro Barrera Kazuko Sukegawa Tadao Orii Naomi Kondo 《Human genetics》1997,101(1):97-101
Mucopolysaccharidosis IVA (MPS IVA) is an autosomal recessive lysosomal storage disorder caused by a genetic defect in N-acetylgalactosamine-6-sulfate
sulfatase (GALNS). In previous studies, we have found two common mutations in Caucasians and Japanese, respectively. To characterize
the mutational spectrum in various ethnic groups, mutations in the GALNS gene in Colombian MPS IVA patients were investigated,
and genetic backgrounds were extensively analyzed to identify racial origin, based on mitochondrial DNA (mtDNA) lineages.
Three novel missense mutations never identified previously in other populations and found in 16 out of 19 Colombian MPS IVA
unrelated alleles account for 84.2% of the alleles in this study. The G301C and S162F mutations account for 68.4% and 10.5%
of mutations, respectively, whereas the remaining F69V is limited to a single allele. The skewed prevalence of G301C in only
Colombian patients and haplotype analysis by restriction fragment length polymorphisms in the GALNS gene suggest that G301C
originated from a common ancestor. Investigation of the genetic background by means of mtDNA lineages indicate that all our
patients are probably of native American descent.
Received: 2 January 1997 / Accepted: 10 June 1997 相似文献
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In order to evaluate the effectiveness and selectivity of various reagents in the solubilization of bacterial membranes, membranes of Micrococcus lysodeikticus were treated with detergents and chaotropic agents. The composition of the extracts so obtained was analyzed by rocket and two-dimensional immunoelectrophoretic techniques. Recovery of succinate-, malate-, and reduced nicotinamide adenine dinucleotide- (NADH) dehydrogenases, ATPase, succinylated lipomannan and cytochromes in the extracts was measured. Treatment with a variety of non-denaturing detergents produced extracts that were generally qualitatively uniform although quantitative differences were observed. The degree of extraction of various components was correlated with the hydrophile-lipophile balance. Several chaotropic agents were also evaluated as reagents for membrane solubilization. These agents were less effective in extraction of bulk protein, but produced extracts enriched in some membrane components. 相似文献
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D K Milton K U Alwis L Fisette M Muilenberg 《Applied and environmental microbiology》2001,67(12):5420-5424
(1-->3)-beta-D-Glucans have been recognized as a potential causative agent responsible for bioaerosol-induced respiratory symptoms observed in both indoor and occupational environments. A specific enzyme immunoassay was developed to quantify (1-->6) branched, (1-->3)-beta-D-glucans in environmental samples. The assay was based on the use of a high-affinity receptor (galactosyl ceramide) specific for (1-->3)-beta-D-glucans as a capture reagent and a monoclonal antibody specific for fungal cell wall beta-D-glucans as a detector reagent. The assay was highly specific for (1-->6) branched, (1-->3)-beta-D-glucans (such as that from Saccharomyces cerevisiae) and did not show any response at 200 ng/ml to curdlan, laminarin, pustulan, dextran, mannan, carboxymethyl cellulose, and endotoxins. The detection level was 0.8 ng/ml for baker's yeast glucan and Betafectin. A coefficient of variation of 7.8% was obtained for (1-->3)-beta-D-glucans in house dust samples. Metal working fluids spiked with (1-->3)-beta-D-glucans inhibited the glucan assay. Because the assay is specific for (1-->6) branched, (1-->3)-beta-D-glucans and is sensitive and reproducible, it will be useful for the investigation of health effects from exposure to this class of biologically active molecules. 相似文献