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1.
Yuji Inaba Yoshio Tanaka Sukemitsu Ishii Tomiaki Morimoto Kunihiko Sato Tuneyoshi Omori Minoru Matumoto 《Microbiology and immunology》1970,14(5):351-360
Replication of Ibaraki virus was not inhibited by 5-iodo-2′-deoxyuridine, indicating that the virus is an RNA virus. The virus was resistant to ether, chloroform and deoxycholate, sensitive to trypsin, very labile at acidic pH but stable at pH 6.4 or higher, and was resistant to repeated freezing and thawing. The virus was readily inactivated at 56 C or higher, was fairly stable at 37 C, and very stable at 4 C, while it rapidly lost infectivity when stored frozen at —20 C. The virus was readily sedimented by centrifugation at 40 000Xg for 60 min. It readily passed through membrane filters of 200 mμ pore size, passed through 100 μfilters but only with some titer loss and did not through 50 mμ filters. In these tests, the bluetongue virus used as a control behaved in the same manner as Ibaraki virus. These findings provide additional evidence for the similarity of Ibaraki virus to bluetongue virus which had been previously demonstrated on the basis of seasonal incidence, symptomatology and pathology of the diseases caused by these viruses and the behavior of the viruses in cell cultures, embryonated eggs and laboratory animals. The present study, however, provided no evidence for any serological relation between these two viruses. More Information is needed to reach a final decision on the classification of Ibaraki virus, particularly regarding the morphology of the virion, the doublestrandedness of the viral RNA and other basic features. 相似文献
2.
Involvement of the Binuclear Copper Site in the Proteolytic Activity of Polyphenol Oxidase 总被引:2,自引:0,他引:2
Plant polyphenol oxidase (PPO) is apt to degrade during andeven after purification. We developed a method to stabilizePPO by 0.3 M NaCl, 0.1% (w/v) Tween 20, and 50% (w/v) ethyleneglycol at pH 6.5. The protein slowly degraded by itself whenthe stabilizing reagents were removed. Ascorbate and/or H2O2accelerated the degradation. The ascorbate-induced degradationwas inhibited by catalase, suggesting that H2O2 is generatedthrough reduction of PPO by ascorbate. It is likely that dissolvedoxygen is converted to peroxide through two-electron reductionby the reaction center of PPO, binuclear Cu site, and a Fenton-typereaction occurred on it. This understanding was supported bythe finding that the H2O2-induced degradation was inhibitedby metal-chelators as well as by polyphenolic substrate of PPO.Considering the postulated mechanism of the self-degradationof PPO, we re-examined the degradation of the 23-kDa proteinof PSII by PPO [Kuwabara et al. (1997) Plant Cell Physiol. 38:179]. The obtained results suggested that the 23-kDa proteintriggers the active oxygen production by the binuclear Cu site,probably as reductant, and receives the radical species preferentiallyto the polypeptide moiety of PPO. (Received April 15, 1999; Accepted July 21, 1999) 相似文献
3.
Hisao Tsukamoto Yoshihiro Kubo David L. Farrens Mitsumasa Koyanagi Akihisa Terakita Yuji Furutani 《The Journal of biological chemistry》2015,290(45):27176-27187
Melanopsins play a key role in non-visual photoreception in mammals. Their close phylogenetic relationship to the photopigments in invertebrate visual cells suggests they have evolved to acquire molecular characteristics that are more suited for their non-visual functions. Here we set out to identify such characteristics by comparing the molecular properties of mammalian melanopsin to those of invertebrate melanopsin and visual pigment. Our data show that the Schiff base linking the chromophore retinal to the protein is more susceptive to spontaneous cleavage in mammalian melanopsins. We also find this stability is highly diversified between mammalian species, being particularly unstable for human melanopsin. Through mutagenesis analyses, we find that this diversified stability is mainly due to parallel amino acid substitutions in extracellular regions. We propose that the different stability of the retinal attachment in melanopsins may contribute to functional tuning of non-visual photoreception in mammals. 相似文献
4.
The laminated structure of the optic tectum is formed by radial and tangential cell migration during development. Studies of developing chick optic tectum have revealed two streams of tangential cell migration in the middle and superficial layers, which have distinctive origins, migratory paths, modes of migration, and destinations. We will review the process of the two types of tangential migrations, in order to elucidate their roles in the formation of the optic tectum layers. 相似文献
5.
Tuneyoshi Omori Yuji Inaba Tomiaki Morimoto Yoshio Tanaka Hiroshi Kurogi Minoru Matumoto 《Microbiology and immunology》1967,11(2):133-142
Five strains of bovine diarrhea virus were isolated from Japanese cattle using bovine tissue cultures. These are the first isolations of this virus from Japanese cattle to be reported. Of importance is the finding that the new isolates, which are non-cytopathogenic, induce an exaltation of Newcastle disease virus in bovine testicular cell culture. This finding has provided a laboratory tool whereby the assay of the virus and its neutralizing antibody can readily be performed. 相似文献
6.
7.
Vegetation dynamics in the coastal area of the Seto Inland Sea region in Japan, where wild fires occur frequently, were described
using a stationary Markov model. In this region, vegetation types ofMiscanthus-Pleioblastus grassland,Lespedeza-Mallotus scrub,Pinus-Rhododendron forest andCrassocephalum-Erechtites community have been identified, and these show cyclic succession under the influence of fires.
The model uses parameters determining fire frequency and rate of successional change to analyze the effect of variation in
these parameters on the areal ratio of each vegetation type at equilibrium and on the time taken for one vegetation type to
succeed another (elapsed successional time). The effect of fire frequency differs between hypothetical habitats with high
and low productivity. A policy for vegetation management in areas of high and low productivity is proposed. The advantages
and limitations of applying Markov models to studies of vegetation succession are also discussed. 相似文献
8.
Identification of a single nucleotide change in a mutant gene for hypoxanthine-guanine phosphoribosyltransferase (HPRTAnn Arbor) 总被引:1,自引:1,他引:0
Shin Fujimori Yuji Hidaka Beverly L. Davidson Thomas D. Palella William N. Kelley 《Human genetics》1988,79(1):39-43
Summary HPRTAnn Arbor is a variant of hypoxanthine (guanine) phosphoribosyl-transferase (HPRT: EC 2.4.2.8), which was identified in two brothers with hyperuricemia and nephrolithiasis. In previous studies, this mutant enzyme was characterized by an increased Km for both substrates, a normal Vmax, a decreased intracellular concentration of enzyme protein, a normal subunit molecular weight and an acidic isoelectric point under native isoelectric focusing conditions. We have cloned a full-length cDNA for HPRTAnn Arbor and determined its complete nucleotide sequence. A single nucleotide change (TG) at nucleotide position 396 has been identified. This transversion predicts an amino acid substitution from isoleucine (ATT) to methionine (ATG) in codon 132, which is located within the putative 5-phosphoribosyl-1-pyrophosphate (PRPP)-binding site of HPRT. 相似文献
9.
Yoshiaki Fukuda Kohzoh Imai Kenju Miura Masashi Matsui Toshihiro Nakanishi Hiroshi Nakazato Johji Masukawa Toshiyuki Higashide Yuji Hinoda Teruhisa Noguchi Akira Yachi 《Cancer immunology, immunotherapy : CII》1988,27(1):26-32
Summary There have been few reports stating that monoclonal antibody alone inhibits human solid tumor growth in vivo. The present study demonstrated that monoclonal antibody S1 (IgG2a), which recognized the antigenic determinant of the carbohydrate moiety, showed antibody-dependent cell (or macrophage)-mediated cytotoxicity (ADCC or ADMC) in conjunction with murine splenocytes of both BALB/c and athymic mice. In vivo experiments demonstrated that the antibody S1 clearly prolonged the survival of athymic mice which had been inoculated with a human liver carcinoma cell line. In addition, the antibody S1 significantly suppressed the human hepatoma line transplanted s.c. into nude mice. 125I-Labeled monoclonal antibody S1 revealed that the antibody accumulated significantly in the tumor mass. Many mononuclear cells were observed surrounding tumor cells when the antibody was given. This model system might be useful for analyzing the ADCC (or ADMC) mechanism in vivo. 相似文献
10.
Yuji Okawara David Ko Steven D. Morley Dietmar Richter Karl P. Lederis 《Cell and tissue research》1992,267(3):545-549
Summary In situ hybridization procedure with a 32P-labelled synthetic oligonucleotide probe was used to detect corticotropin-releasing factor-encoding messenger RNA (CRF mRNA) in the hypothalamus of the white sucker, Catostomus commersoni. Adjacent sections were immunostained by a sucker CRF-specific antiserum. CRF mRNA-containing neurons were identified by autoradiography in the magnocellular and parvocellular subdivisions of the preoptic nucleus (PON). Many of these neurons were also immunostained by sucker antiserum, showing the same distribution patterns. These results confirm the presence of CRF mRNA and CRF peptide in the white sucker hypothalamus and support the view that the magnocellular and parvocellular neurons of the PON may be involved in the control of adrenocorticotropic hormone secretion from the pituitary in the white sucker. 相似文献