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201.
Genetic characterization of an avian H4N6 influenza virus isolated from the Izumi plain,Japan
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Masakazu Kuwahara Aya Matsuu Tatsunori Masatani Shigehisa Toda Makoto Ozawa 《Microbiology and immunology》2017,61(11):513-518
202.
Ozawa M Honda K Nakai I Kishida A Ohsaki A 《Bioorganic & medicinal chemistry letters》2008,18(14):3992-3994
An indole alkaloid (hypaphorine (1)) was isolated from Brazilian medicinal plant, Erythrina velutina (Leguminosae). This compound was investigated for sleep promoting effects in mice, and the results showed that it significantly increased non-rapid eye movement (NREM) sleep time during the first hour after its administration. The NREM sleep time was enhanced by 33% in the experimental mice when compared to that of the controls. This study therefore confirmed its sleep promoting property. 相似文献
203.
Hirabayashi A Mukaiyama H Kobayashi H Shiohara H Nakayama S Ozawa M Tsuji E Miyazawa K Misawa K Ohnota H Isaji M 《Bioorganic & medicinal chemistry》2008,16(20):9247-9260
Spleen tyrosine kinase (Syk) and zeta-associated protein kinase of 70k Da (ZAP-70) are members of the Syk family and non-receptor-type protein tyrosine kinases, which play crucial roles in B- and T-cell activation. Therefore, a Syk family tyrosine kinases inhibitor would be a useful therapeutic agent for the treatment of various allergic disorders and autoimmune diseases. Previously, we reported that 1,2,4-triazolo[4,3-c]pyrimidine derivative 1 and 1,2,4-triazolo[1,5-c]pyrimidine derivative 2 showed strong inhibitory activities against Syk family kinases. These compounds also exhibited high-level suppression of IL-2 in cellular assays. However, their oral efficacies were poor in a mouse model of IL-2 production. To improve oral effectiveness, we investigated a new series of Syk family kinases inhibitors. We found that imidazo[1,2-c]pyrimidine derivatives potently inhibited the Syk family kinases. Among these agents, compound 9f not only showed strong inhibitory activities against Syk and ZAP-70 kinases in vitro, but its oral administration resulted in the in vivo suppression of both the passive cutaneous anaphylaxis reaction and Concanavalin A-induced IL-2 production in a mouse model. 相似文献
204.
Somfai T Ozawa M Noguchi J Kaneko H Karja NW Fahrudin M Nakai M Maedomari N Dinnyés A Nagai T Kikuchi K 《Animal reproduction science》2008,107(1-2):131-147
Embryo development during in vitro culture of polyspermic porcine oocytes was investigated in the present study. After in vitro fertilization (IVF) of in vitro matured oocytes, putative zygotes were centrifuged to visualize pronuclei. Two pronuclear (2PN) and poly-pronuclear (PPN) zygotes were selected and cultured in vitro. Their development to the blastocyst stage and total cell numbers, dead cell rates and ploidy at the blastocyst stage and morphology of resultant embryos after first cleavage were compared. A cleavage rate of PPN embryos was lower than that of 2PN (61.3% and 82.2%, respectively), however, the ability of cleaved embryos to develop to the blastocyst stage did not differ between the PPN and the 2PN groups (22.4% and 32.9%, respectively). Also there was no difference in total cell numbers and rates of dead cells between PPN and 2PN blastocysts. The majority of blastocysts in 2PN group were found to be diploid. In contrast, blastocysts in PPN group showed heterogeneous status in their ploidy including polyploidy and mixoploidy, whereas a remarkable proportion (31.3%) of them was found to be diploid. After the first cleavage (at 36 h after IVF), there was no difference in the number of nuclei/embryo between the two groups, nevertheless embryos in PPN group had significantly higher numbers of blastomeres than that of embryos in 2PN group, mainly due to an increased frequency of anuclear blastomeres. The present results indicate that correction of embryo ploidy in polyspermic embryos can occur during IVC. Nevertheless the frequency of partial fragmentation in polyspermic embryos is increased. 相似文献
205.
Abe M Ozawa Y Morimitsu Y Kubota K 《Bioscience, biotechnology, and biochemistry》2008,72(10):2681-2686
We isolated a novel pungent principle from the flower buds of myoga. Based on an interpretation of the HR-MS, EI-MS, IR, UV, and NMR data, this compound was (8betaH)-14,17-cyclolabda-12,14(17)-diene-15,16-dial (mioganal, 1). We determined the threshold value of mioganal to be 5.6x10(-5) g/ml, which is about eight times greater than that of 8beta(17)-epoxy-12(E)labdene-15,16-dial (miogadial), the main pungent principle in the flower buds of myoga. In addition, we examined the content of mioganal in different parts of different varieties. Mioganal is mainly distributed in the leaves of both natsumyoga and akimyoga varieties at 1.60 mg/100 g fresh weight on average, its amount being three times higher than that in the flower buds. 相似文献
206.
During the R/V Hakuho-maru Cruise KH-95-2, Ocean Research Institute, University of Tokyo, from Tokyo, Japan to the South Pacific east of Australia (22°
N–30° S; 126° E–176° E) from June to September, 1995, 77 unidentified gonostomatid larvae (5.5–20.0 mm SL) were collected
south of 20° S with an IKMT net. They subsequently were identified as Sigmops longipinnis (Mukhacheva), and its ontogeny during the latter part of the larval stage (body form and proportions, photophores, pigmentation,
and meristics) is described here. The larvae develop a species-specific row of melanophores along the midlateral line anterior
to the caudal peduncle and another along the middorsal line from before the dorsal fin to just before the caudal fin.
Received: June 24, 2002 / Revised: November 2, 2002 / Accepted: January 31, 2003 相似文献
207.
We describe a simple method to accurately differentiate Candida albicans isolates by concurrent use of the restriction enzyme digestion patterns for PCR products, targeting two species-specific
DNA regions originating from genetically different sources, the nuclear and mitochondrial genomes. The target sequence we
used as the nuclear gene was derived from the PHO85 gene, a negative regulator of the PHO system, in which we found a restriction size polymorphism within the two alleles of
PHO85 in the diploid genome of this fungus. The mitochondrial target was derived from EO3, a species-specific DNA fragment possessing
a small size polymorphism among various clinical isolates. Our results should provide a new tool for molecular epidemiological
surveys of patients suffering from candidiasis caused by C. albicans. 相似文献
208.
Shigeaki Ito Shigeki Hamada Hiroyuki Ito Hirokazu Matsui Tadahiro Ozawa Hidenori Taguchi Susumu Ito 《Biotechnology letters》2009,31(7):1065-1071
The cellobiose 2-epimerase from Ruminococcus albus (RaCE) catalyzes the epimerization of cellobiose and lactose to 4-O-β-d-glucopyranosyl-d-mannose and 4-O-β-d-galactopyranosyl-d-mannose (epilactose). Based on the sequence alignment with N-acetyl-d-glucosamine 2-epimerases of known structure and on a homology-modeled structure of RaCE, we performed site-directed mutagenesis
of possible catalytic residues in the enzyme, and the mutants were expressed in Escherichia coli cells. We found that R52, H243, E246, W249, W304, E308, and H374 were absolutely required for the activity of RaCE. F114
and W303 also contributed to catalysis. These residues protruded into the active-site cleft in the model (α/α)6 core barrel structure. 相似文献
209.
Some plants are more mycorrhizal than others and mycorrhizal colonisation of plants in extreme environments is frequently additionally reduced due to decreased spore density and/or diversity and therefore frequently overlooked. We analysed two plant species from both metal polluted and saline enriched soils with differing mycorrhizal colonisation levels/status using classical and molecular methods. The selected plant species were Sesleria caerulea (L.) Ard. and Thlaspi praecox Wulfen from a metal polluted site, and Limonium angustifolium (Tausch) Degen [Statice serotina Rchb., L. vulgare Mill. subsp. Serotinum (Rchb.) Gams] and Salicornia europaea L. from the Se?ovlje salterns in Slovenia. Despite the high mycorrhizal frequencies (F%) observed, the presence of arbuscules (A%) was at best low in S. caerulea and T. praecox, and undetectable in L. angustifolium and S. europaea. Temporal temperature gradient gel electrophoresis (TTGE) was applied to field-collected samples from both burdened environments and proved to be an effective technique for rapid profiling and identification of arbuscular mycorrhizal fungi (AMF). Sequencing and phylogenetic analysis confirmed the association of AMF of the genus Glomus with roots of all four plant species. This is the first report on the identification and profiling of Glomeromycota in the field-collected Cd/Zn metal hyperaccumulator T. praecox growing at a highly metal polluted site, as well as in L. angustifolium and S. europaea collected in a saline environment. The identification of AMF from both ecosystems only partially resembles previous identifications on the basis of spores. 相似文献
210.
Hamasu K Haraguchi T Kabuki Y Adachi N Tomonaga S Sato H Denbow DM Furuse M 《Amino acids》2009,37(2):377-382
The purpose of the present study was to clarify the central nervous system function of amino acids during acute stress. In
Experiment 1, changes in free amino acid pattern were investigated in the brain of neonatal chicks exposed to either restraint
with isolation-induced or fasting stress. l-Proline and l-arginine were decreased in the telencephalon and diencephalon under any stress. Since the central nervous system functions
of l-arginine during the stress response has recently been reported, in Experiment 2, the effect of intracerebroventricular injection
of l-proline (0.5, 1.0, 2.0 μmol) during isolation-induced stress was investigated. l-Proline induced sedative and hypnotic effects in a dose-dependent manner. It is suggested that l-proline may have an important role to attenuate the stress response in the central nervous system of chicks. 相似文献