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91.
A series of truncated analogs of α-galactosylceramide with altered ceramide moiety was prepared, and evaluated for Th2-biased response in the context of IL-4/IFN-γ ratio. Phytosphingosine-modified analogs including cyclic, aromatic and ethereal compounds as well as the C-glycoside analog of OCH (2) with their cytokine inducing profile are disclosed.  相似文献   
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Knowledge of the comparative anatomy of tongue musculature is crucial to the discussion of the origin and the evolution of speech because of the indispensable role played by this organ in speech. However, the tongue musculature of primates has rarely been studied. In a previous study, the author analyzed human tongue musculature and developed a 3D model of this organ [Takemoto, Journal of Speech, Language, and Hearing Research 44:95-107, 2001]. In this study, the tongue musculature of chimpanzees was examined using methods similar to those used for humans. Results showed that tongue musculature was topologically the same for both humans and chimpanzees. As in humans, the tongue musculature of chimpanzees consisted of inner and outer regions. The inner musculature was composed of serial "structural units," made up of two types of laminae whose fibers were perpendicular to the tongue surface. The outer musculature was a thin layer of fibers oriented parallel to the surface and superficial to the inner musculature. Although the tongue musculature of humans and chimpanzees is similar, the external shapes differ: the chimpanzee tongue is flat, whereas the human tongue is round. Applying the muscular hydrostat theory to the external shape of the tongue suggests that the primary actions of the chimpanzee tongue are protrusion and retrusion, whereas the human tongue can be deformed in the oral cavity with a high degree of freedom. It is hypothesized that the evolution of the external shape of the tongue is one of the factors that led to the development of human speech. The results of this study suggest that modeling based on muscular hydrostatic theory of the effects of changes in external tongue shape on articulatory movements should be included in discussions on the origin of speech.  相似文献   
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The ectomycorrhizal basidiomycete Tricholoma matsutake produces commercially valuable fruit bodies, matsutake, in forests. Here we report a PCR system targeting retroelement integration sites to differentiate among individual Asian isolates of T. matsutake based on their geographical origins, such as Japan, the area of South Korea through North Korea, the northeastern provinces of China, and the area of the southwestern provinces of China through Bhutan. The overall misjudgment rate of the analytical system was approximately 5% based on 95 samples of T. matsutake examined including those from cultures and from commodities. We also provide evidence that T. matsutake isolates grown throughout the Far East, including the northeastern provinces of China, are closely related to each other while distinct from those in the area of the southwestern provinces of China through Bhutan. The method allows us to trace back geographical origins of Asian matsutake, thus contributing to food safety, appropriate tariffs, and proper price setting.  相似文献   
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Staphylocoagulases (SCs) have been classified by the differences in antigenicity using a serological method. We have developed a system to classify them based on the nucleotide differences in SC genes (coa). The system was composed of three multiplex PCRs (M-PCRs): M-PCR:A, identifying types III, IV, VII, and VIII; M-PCR:B, identifying types I, II, V, and VI; M-PCR:C, identifying three subtypes of type VI. In this study, we found that coa genes of the serotype VI were not identical, but classified into three subtypes based on the nucleotide differences, especially in D2 and the central region: VIa, the coa gene carried by stp12 from human; and VIb and VIc, the coa genes carried by strains IFH556 and IFH514 isolated from bovine raw milk. The primer pair used in M-PCR:B was designed to identify all three subtypes of type VI coa. The results showed that coa types of 154 out of 155 Staphylococcus aureus strains from various origins assigned by M-PCR:A and B were identical to those obtained by serological methods, leaving a serotype IV strain unclassifiable. All 73 type VI strains were classified into one of three subtypes by M-PCR:C. Furthermore, we found that type VIa and VIb strains carried characteristic pyrogenic toxin superantigen genes, while no toxin genes were identified in type VIc strains, suggesting the correlation between the subtype of type VI coa gene and the carriage of genomic islands. Our results showed that these M-PCRs are convenient methods for SC typing that might be useful for epidemiological studies.  相似文献   
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The stalk protein L12 is the only multiple component in 50S ribosomal subunit. In Escherichia coli, two L12 dimers bind to the C-terminal domain of L10 to form a pentameric complex, L10[(L12)(2)](2), while the recent X-ray crystallographic study and tandem MS analyses revealed the presence of a heptameric complex, L10[(L12)(2)](3), in some thermophilic bacteria. We here characterized the complex of Thermus thermophilus (Tt-) L10 and Tt-L12 stalk proteins by biochemical approaches using C-terminally truncated variants of Tt-L10. The C-terminal 44-residues removal (Delta44) resulted in complete loss of interactions with Tt-L12. Quantitative analysis of Tt-L12 assembled onto E. coli 50S core particles, together with Tt-L10 variants, indicated that the wild-type, Delta13 and Delta23 variants bound three, two and one Tt-L12 dimers, respectively. The hybrid ribosomes that contained the T. thermophilus proteins were highly accessible to E. coli elongation factors. The progressive removal of Tt-L12 dimers caused a stepwise reduction of ribosomal activities, which suggested that each individual stalk dimer contributed to ribosomal function. Interestingly, the hybrid ribosomes showed higher EF-G-dependent GTPase activity than E. coli ribosomes, even when two or one Tt-L12 dimer. This result seems to be due to a structural characteristic of Tt-L12 dimer.  相似文献   
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Monoclonal antibodies against human plasminogen activator urokinase have been produced. A G62 hybridoma-producing antibody (IgG) was purified on a DEAE-cellulose column, and it proved useful for the measurement, identification and purification of antigens that had approximate molecular weights of 55- and 33-Kdaltons. For immunochemical measurements and purification, a competitive enzyme-linked immunosorbent assay (ELISA) and affinity chromatography using antibody-immobilized Sepharose 4B were developed. The ELISA has sensitivity to 20 p mole antigen molecules. The binding capacity of the antigen on the affinity column was evaluated on SDS-polyacrylamide slab gels as well as by fibrin autography and ELISA. Results showed that there was quantitative purification with no loss of enzyme activity in the one-step procedure. Western blotting and affinity binding showed antigenic bands with apparent molecular weights of 55- and 33-Kdaltons. Because the 55-Kdalton form contains 33- and 22-Kdalton components connected by a disulfide bond, the epitope domain is present on the 33-Kdalton chain. Using this antibody, we examined human kidney sections by direct immunofluorescence to locate the antigen. It was found in epithelial cells convoluted segments, in glomerulus cells and in capillary endothelial cells, evidence that renal tubular cells synthesize the antigen which then is secreted in urine.  相似文献   
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