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21.
Expression cloning of gamma interferon-inducing antigens of Mycobacterium avium subsp. paratuberculosis 下载免费PDF全文
Three recombinant proteins, Map10, Map39, and Map41, produced based on nucleotide sequences obtained from the screening of Mycobacterium avium subsp. paratuberculosis genomic library expressed in Escherichia coli significantly elicited gamma interferon production in peripheral blood mononuclear cells from infected cattle. Two of these proteins were members of the PPE protein family. 相似文献
22.
Yasuyuki Suzuki Yoshio Inoue Riichir Chûj 《Macromolecular chemistry and physics.》1980,181(1):177-191
The origin of the chemical shift differences of carbons in polypeptides which accompany the helix-coil transition has been investigated by using oligopeptides, benzyloxycarbonyl-γ-ethyl-L -glutamyl-diethyl-L -glutamate and benzyloxycarbonyl-di-(γ-ethyl-L -glutamyl)-diethyl-L -glutamate, as models of the backbone of polypeptides. Structures of aggregates in deuterated chloroform were proposed for these oligopeptides on the basis of concentration dependence and temperature dependence of the chemical shifts of protons and carbons, and spin-lattice relaxation times. Antiparallel and/or parallel “in-register” structures for extended forms and “out-of-register” network of extended forms are coexisting in deuterated chloroform solution for these oligopeptides. From the shift for the carbons of the oligopeptides induced by organic acids, it was in ferred that down-field shifts are induced at α and amide carbons in polypeptides by organic acids. By comparing the induced shift of the carbons in the peptides with the chemical shift differences of the carbons in polypeptides which accompany the helix-coil transitions, it was found that the conformational changes play a predominant role in the origin of the chemical shift differences of the carbons in polypeptides which accompany the helix-coil transitions, it was found that the conformational changes play a predominnant role in the orgin of the chemical shift differences of amide, α, β, and γ carbons in polypeptides. 相似文献
23.
Use of an Enrichment Broth Cultivation-PCR Combination Assay for Rapid Diagnosis of Swine Erysipelas 总被引:4,自引:1,他引:4 下载免费PDF全文
Yoshihiro Shimoji Yasuyuki Mori Koji Hyakutake Tsutomu Sekizaki Yuichi Yokomizo 《Journal of clinical microbiology》1998,36(1):86-89
We have previously described the creation by Tn916 mutagenesis of avirulent transposition mutants from a highly virulent strain of Erysipelothrix rhusiopathiae, the causative agent of swine erysipelas. In this study, we cloned a 2.2-kb DNA fragment which flanked the Tn916 insertion in an avirulent mutant (strain 33H6) and evaluated the possibility that this region could be used for the specific detection of E. rhusiopathiae. According to the sequences of this region, oligonucleotide primers were designed to amplify a 937-bp fragment of the E. rhusiopathiae chromosome by PCR. The specificity of the PCR was investigated by analyzing 64 strains of Erysipelothrix species and 27 strains of other genera different from Erysipelothrix. A 937-bp DNA fragment could be amplified from all E. rhusiopathiae strains tested, and no amplification was observed by using DNAs from the other species tested. To make a rapid and definite diagnosis of swine erysipelas in slaughterhouses, we developed an enrichment broth cultivation-PCR combination assay, which used a commercially available DNA extraction kit, to identify E. rhusiopathiae in the specimens from swine with arthritis. After samples were enriched in selective broth culture, detection of E. rhusiopathiae was tested by either conventional methods or the PCR. Of 102 samples tested, 15 samples were positive by conventional methods and 12 of the 15 samples were positive by the PCR. The detection limit of the PCR was 103 CFU per reaction mixture for the PCR-positive samples. These results indicate that this PCR technique could be used as a first-line screening technique for the specific detection of E. rhusiopathiae in specimens. 相似文献
24.
Miki Kaneko Toshikazu Uchida Mitsuhiko Moriyama Yasuyuki Arakawa Toshio Shikata Kenichiro Gotoh Satoaki Mima 《Journal of medical virology》1995,47(3):204-208
A pathogenic role of precore-defective mutation in the onset of fulminant hepatitis B has been suggested. However, precore-defective mutants do not always cause fulminant hepatitis B and are not always isolated from affected patients. These findings strongly suggest the presence of some additional important mutations outside the precore region in fulminant hepatitis. In the present investigation an attempt was made to sequence the X open reading frame of hepatitis B virus DNA isolated from seven patients with fulminant hepatitis B and five patients with acute hepatitis B. The latter were used as controls. Since the X open reading frame encodes the X protein and contains the core promoter/enhancer II complex, some critical mutations may enhance or disrupt the replication and expression of hepatitis B virus DNA leading to fulminant hepatitis. A C-to-T substitution was found at nucleotide (nt) 1655, an A-to-T substitution at nt 1764 and a G-to-A substitution at nt 1766 in 4, 5 and 5 patients, respectively, out of the seven with fulminant hepatitis. These substitutions were not recognized in the patients with acute hepatitis. These mutations might change the function of the X protein and core promoter/enhancer II complex. It is suggested, therefore, that these mutations, as well as the precore-defective mutation, may play an important role in the pathogenesis of fulminant hepatitis. © Wiley-Liss, Inc. 相似文献
25.
Yasuyuki Sumikawa Yuriko Ueki Akira Miyoshi Lei Cheng Min Yin Hai-Bo Shi Masuko Daitoku Sumikawa Takeshi Kono Toshiyuki Aoki Ichiro Katayama 《Arerugī》2007,56(10):1270-1275
BACKGROUND: The comparative studies of the prevalence of atopic dermatitis and skin barrier functions in Japanese and Chinese were performed. METHODS: Clinical investigations were performed in 68 elementary school students in Lhasa, Tibet Autonomous Region and 67 students in Yixing, Jiangsu Province in China, and 99 students in Nishinomiya, Hyogo in Japan. Transepidermal water loss (TEWL) and capacitance were measured. Questionary survey about bathing frequency was also performed for students in Lhasa, Yixing and Osaka. RESULT: The prevalence rate of atopic dermatitis was 0% in Lhasa, 2.63% in Yixing, 4.26% in Nishinomiya. TEWL of students in Nishinomiya was higher than that in Yixing and Lhasa. Capacitance of students in Lhasa was lower than that in Nishinomiya and Yixing. The frequency of taking a bath in Lhasa was about 2.2 times per month and fewer than that in Nishinomiya and Yixing. CONCLUSION: There was tendency that the prevalence of atopic dermatitis increased according to increase of TEWL. It was thought that more investigations are necessary whether the development of habitat and environment influence the prevalence of atopic dermatitis and skin barrier function. 相似文献
26.
27.
Yasuyuki Tezuka Hiroshi Imai Tomoo Shiomi 《Macromolecular chemistry and physics.》1997,198(2):627-641
A series of mono- and bifunctional polystyrenes ( 1 c and 1 ′ c ) having 1-methylpyrrolidinium salt end groups were prepared through sequential derivatization, i.e., tosylation and quaternization reactions, of prepolymers having 3-hydroxypropyl groups ( 1 a and 1 ′ a ) produced by end-capping reactions of the relevant living polymers. The 1-methylpyrrolidinium salt end group was found to undergo a selective ring-opening reaction at 100°C by nucleophilic attack of a benzoate counter anion introduced by ion-exchange reaction. The ion-coupling reaction of 1 c and 1 ′ c with poly(styrene-co-acrylate salt) was found to take place upon coprecipitation of an equimolar mixture into methanol to afford ionically linked pseudo-graft and network products, respectively. The subsequent heat treatment, converting the ionic bond into a covalent one, results in branched and crosslinked polystyrene with predetermined structural parameters. 相似文献
28.
Hideki Tamura Yasuyuki Ishikawa Noriko Hino Maoko Maeda Shigeru Yoshida Shinsuke Kaku Sadao Shiosaka 《The Journal of physiology》2006,570(3):541-551
Long-term potentiation (LTP) is thought to be particularly important in the acquisition of hippocampus-associated memory, in part because it develops quickly and persists for indefinite periods. Extracellular proteolysis has been hypothesized to contribute to LTP by modifying adhesive relations of synapses and thus the morphology of excitatory synapses. Here we report that neuropsin (NP), an extracellular serine protease, is critically involved in the formation of both the potentiation effect and hippocampus-dependent forms of memory. NP-knockout mice were significantly impaired in the Morris water maze and Y-mazes and failed to exhibit early phase LTP induced by a single tetanus. Potentiation was also impaired or completely blocked by in vivo application of a specific inhibitor or a neutralizing monoclonal antibody for NP. Intriguingly, recombinant (r-) NP alone, without tetanic stimulation, elicited either long-lasting potentiation or depression, depending on the applied dose. The r-NP-elicited potentiation was occluded by prior induction of LTP, while theta-burst-elicited LTP was occluded by application of r-NP alone, suggesting that the two forms of plasticity have a common signalling pathway. r-NP-elicited potentiation and depression increased phosphorylation at different sites on the GluR1 subunit of the AMPA receptor that had previously been associated with LTP or long-term depression. Thus, we conclude that NP is necessary for establishment of LTP and has a significant role in memory acquisition. 相似文献
29.
Bae JW Takahashi I Sasano Y Onodera K Mitani H Kagayama M Mitani H 《Journal of anatomy》2003,203(2):235-241
Matrix metalloproteinases (MMPs) have been implicated in physiological cartilage matrix remodelling as well as in pathological and invasive extracellular matrix remodelling of tissue. Age-related changes in the gene expression patterns of MMPs in mandibular condylar cartilages (MCCs) were analysed. We examined the gene expression patterns of Mmp-8 and -13 and their substrates, Col1a1, Col2a1 and Col10a1, in MCC of growing and ageing rats. Temporomandibular joints of male Wistar rats aged 4, 8, 16 and 32 weeks were subjected to in situ hybridization analysis. Histologically, MMCs showed characteristics of growth plate cartilage at ages 4 and 8 weeks, and more closely resembled articular cartilage thereafter. Mmp-8 was expressed in the cells in all cartilaginous cell layers at ages 4 and 8 weeks, and then was localized only in the mature cells at ages 16 and 32 weeks. Whereas Mmp-13 expression was limited to the lowermost hypertrophic chondrocytes in the growth stage, mature chondrocytes instead of hypertrophic chondrocytes expressed Mmp-13 in adult non-hypertrophic MCC. Because Mmp-8 and -13 expression overlapped with Col2a1 and Col10a1, chondrocytes could play a pivotal role in degradation as well as production of the cartilaginous matrix in MCC. 相似文献
30.
Hidekazu SHIGEMATSU Yutaka KOBAYASHI Sumio TATBNO Yasuyuki HIKI Sadahito KUWAO 《Pathology international》1983,33(2):367-380
The glomerular lesions In 129 cases of IgA nephritis were analyzed. The development of glomerular injury occurred in two ways, one being a chronic mesangial depositive and sclerosing lesion commonly found in most glomeruli, and the other an acute but local injury initiating from the local peripheral glomerular basement membrane abnormality, i.e., thinning and/or splitting, which was seen at least in one third of all cases. The activation of the local coagulatory process could add segmental glomerular changes including small crescents, adhesion, and local tuft necrosis to the mesangial lesion. ACTA PATHOL. JPN. 33; 367–380, 1983. 相似文献