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81.
K Nomoto T Takemoto M Maeda Y In M Doi M Inoue T Ishida 《Biochemical and biophysical research communications》1992,187(1):325-331
As an aid for developing a new type of potent insecticide acting on the neuromuscular junction, conformational characteristics of domoic acid and isodomoic acid A, the naturally occurring glutamate agonists, were investigated by X-ray crystal analyses. Conformational comparison with a neuroactive alpha-kainic acid provides information concerning the stereochemical feature responsible for the biological activity. 相似文献
82.
Increased in vitro responses of tracheal smooth muscle from hyperresponsive guinea pigs 总被引:1,自引:0,他引:1
Repeated aerosol antigen challenge of previously sensitized guinea pigs induces airway hyperresponsiveness to inhaled acetylcholine. To determine the mechanism producing these airway changes and assuming that changes in the trachealis muscle reflect changes in muscle of the entire tracheobronchial tree, we examined the in vitro smooth muscle mechanics and morphometric parameters of tracheae from guinea pigs demonstrating hyperresponsiveness in vivo vs. tracheae from control guinea pigs. No differences between these groups were found in luminal volume at zero transmural pressure, passive pressure-volume characteristics, or area of airway wall. Smooth muscle areas were slightly less in tracheae from hyperresponsive guinea pigs. Tracheae from hyperresponsive guinea pigs had both significantly increased isovolumetric force generation and isobaric shortening compared with tracheae from controls when evaluated over the range of transmural pressures from -40 to 40 cmH2O. We conclude that the in vivo airway hyperresponsiveness induced with repeated antigen challenge is associated with both increased force generation and shortening of tracheal smooth muscle without increased muscle mass, suggesting enhanced contractile activity. 相似文献
83.
Hiroyuki Tsunoda Toshio Ohshima Jun Tohyama Masayuki Sasaki Norio Sakuragawa Frank Martiniuk 《Human genetics》1996,97(4):496-499
We report a missense mutation in an adult Japanese patient with acid alpha-glucosidase (GAA) deficiency. A TC to GT transition
at nucleotides 1585–1586, was identified. This transition resulted in an amino acid substitution of Ser-529 to Val (S529V)
in exon 11. We also have demonstrated that the S529V mutation abolishes the catalytic activity of the enzyme. Our data suggest
that this mutation is the cause of the clinical manifestation known as adult-onset GAA deficiency. The missense mutation described
here is a new mutation, and the first identified in Japanese patients with GAA deficiency.
Received: 23 May 1995 相似文献
84.
85.
Hiroyuki Yamaguchi Hitoshi Miura Kazuoki Ohsumi Takako Osaki Haruhiko Taguchi Tomoko Yamamoto Tomoko Hanawa Sachio Ogata Shigeru Kamiya 《Microbiology and immunology》1996,40(1):77-80
To determine amino acid sequences of the epitopes recognized by monoclonal antibodies (mAbs) 3C8 and 5C3 directed against Yersinia enterocolitica heat-shock protein (HSP60), a dot blot analysis was perfomed using synthesized peptides of Y. enterocolitica HSP60 such as peptides p316-342, p327-359, p340-366, p316-326, p316-321, p319-323, and p321-326 which represent positions of amino acids in Y. enterocolitica HSP60. The dot blot analysis revealed that 5C3 mAb reacted with p316-342, p316-326 and p321-326, and 3C8 mAb p316-342 and p316-326. These results indicate that the epitopes recognized by the mAbs were associated with eleven amino acids, Asp Leu Gly Gln Ala Lys Arg Val Val Ile Asn, of p316-326. The sequence homology between p316-326 of Y. enterocolitica HSP60 and the rest of the HSP60 family suggests that the five amino acids of Lys, Arg, Val, Ile and Asn, which are highly conserved in the HSP60 family, might be related with the epitope recognized by 3C8. In contrast, it was also demonstrated that three amino acids of Leu, Gly and Val, which are not well conserved in the HSP60 family, might be related to the epitope recognized by 5C3. 相似文献
86.
Aino virus (AIV; JaNAr 28 strain) 103 TCID50/0.2 ml was inoculated in the yolk sac of 8-day-old chick embryos. Recovery and titration of the virus from various organs including the central nervous system (CNS) and skeletal muscle were performed at 2, 4, 7, 10 and 13 days after inoculation (PI). AIV was systemically disseminated and proliferated even 2 days PI. The titers of the recovered virus from the CNS and from skeletal muscle was the highest at 4 days PI and declined with time, whereas hydranencephaly, arthrogryposis and cerebellar hypoplasia developed at 7 days PI and gradually progressed until 13 days PI. 相似文献
87.
Comparison of OspA Serotypes for Borrelia burgdorferi Sensu Lato from Japan,Europe and North America
Toshiyuki Masuzawa Bettina Wilske Tetsuro Komikado Hiroyuki Suzuki Hiroki Kawabata Nanao Sato Koichi Muramatsu Nobutake Sato Emiko Isogai Hiroshi Isogai Russell C. Johnson Yasutake Yanagihara 《Microbiology and immunology》1996,40(8):539-545
Sixty-one Borrelia burgdorferi sensu lato strains from various sources (ticks, human, and wild animals) in Japan and two strains from ticks in Far Eastern Russia were classified on the basis of reactivity with 16 monoclonal antibodies (mAb) to outer surface protein A (OspA) and by DNA-DNA hybridization assay. Eleven OspA serotypes (J1 to J11) were recognized among the Japanese and the Far East Russian isolates (serotypes J1 to J9 were identified as B. garinii, serotype J10 was identified as B. afzelii, and serotype J11 corresponded to B. japonica), whereas 7 OspA serotypes for North American and European isolates previously reported (Bettina Wilske et al, J. Clin. Microbiol. 31:340-350, 1993) were not observed except for OspA serotype 2 which showed identical reactivity with OspA serotype J10. This finding provides helpful information for understanding the geographical distribution of Lyme disease borrelia and the development of vaccine and diagnostic tests. In conclusion: 1. B. burgdorferi sensu stricto has not been observed in Japan, 2. Japanese B. afzelii isolates are closely related to those from Europe, 3. B. garinii isolates from Japan are highly heterogeneous and apparently different from European B. garinii isolates. 相似文献
88.
Koike Hiroyuki; Yoneyama Koichi; Kashino Yasuhiro; Satoh Kazuhiko 《Plant & cell physiology》1996,37(7):983-988
Interactions of externally added plastoquinone (PQ) derivatives(PQ0-PQ3) with the photosystem II (PSII) acceptor side wereinvestigated in PSII membrane fragments prepared from spinachby measuring the photoreduction rates of PQ derivatives at variousPQ concentrations, and the following results were obtained. From the kinetic analysis, all the PQ derivatives (PQ0-PQ3)except PQ3 were shown to accept electrons at two sites (theQB site and the PQ site) as in the case of Synechococcus vulcanusPSII particles with benzoquinone derivatives [Satoh et al. (1995)Plant Cell Physiol. 36: 597]. Affinities of PQ derivatives at the QB site increased as thelength of the isoprene side chain got longer, while those atthe PQ site were not very much different for all the PQ derivativestested in this study. The inhibitory effect of DCMU was noncompetitive, and, therefore,the affinity of PQ3 for the PQ site was determined while thatfor the QB site could not be estimated presumably due to itsfairly high affinity to the site. Based on the results obtained using PQ derivatives, the mechanismof interaction of an authentic PQ, PQ9, at the QB site is discussed. (Received May 2, 1996; Accepted July 24, 1996) 相似文献
89.
Shinichiro Nakamura Wijit Kiatipattanasakul Hiroyuki Nakayama Fumiko Ono Ippei Sakakibara Yasuhiro Yoshikawa Naoaki Goto Kunio Doi 《Journal of medical primatology》1996,25(4):294-300
Abstract: In this study, we immunohistochemically examined the several constituents of senile plaques (SPs) and cerebral amyloid angiopathy (CAA) in aged cynomolgus monkeys. Apolipoprotein E (apoE) deposited in all mature plaques and CAA, and in half of the diffuse plaques. Alpha-1-antichymotripsin (αACT) deposited in half of the mature plaques and in one third of the CAA. Amyloid precursor protein (APP), ubiquitin (Ub), and microtubule-associated protein-2 (MAP-2) accumulated in the swollen neurites of mature plaques. Glial fibrillary acidic protein (GFAP) was detected in the astrocytes and their processes surrounding the mature plaques. Tau was detected in neither the SPs nor CAA. Therefore, mature plaques involved extracellular Aβ, apoE, and αACT, and also astrocytes and swollen neurites. However, diffuse plaques involved only extracellular Aβ and apoE. Since these features, except for tau, were consistent with those in humans, this animal model will be useful for studying the pathogenesis of cerebral amyloid deposition. 相似文献
90.
The immunomodulating effects of preoperative sizofiran (SPG) administration on regional lymph nodes were studied in patients
with stage III or IV head and neck cancer, by comparing the immunofunction of peripheral blood. The regional lymph nodes were
dissected surgically, and freshly obtained mononuclear cells were studied to investigate the interleukin-2 (IL-2) production,
the LAK and NK activities, and the quantitative analysis of the surface phenotype of the mononuclear cells. The results indicated
that SPG enhanced immunological activities in the regional lymph nodes, as shown by increased IL-2 production and cytotoxic
activities of the effector cells (NK, LAK), and increased helper T lymphocytes (CD4+) in the tumor-uninvolved lymph nodes. The immunofunction following SPG administration was attenuated, but was still augmented
in the regional lymph nodes with metastases. Therefore, SPG was found to be a biologic response modifier to enhance the immunofunctions
of the regional lymph node in patients with head and neck cancer. 相似文献