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61.
Montira Yossapol Kasumi Suzuki Justice Opare Odoi Michiyo Sugiyama Masaru Usui Tetsuo Asai 《Microbiology and immunology》2020,64(10):712-718
To clarify the persistence of extended-spectrum β-lactamase (ESBL) producers, 13 plasmids from two broiler farms were analyzed. On the farm not using antimicrobials, one plasmid from Klebsiella pneumoniae isolated from a day-old chick was similar to that from Escherichia coli isolated a year later, with the deletion of two transposons. On the farm using antimicrobials, most circulating plasmids (eight out of nine) in a flock of 40-days-old chicks were identical, although one from K. pneumoniae had a deletion of a transposon carrying a class 1 integron containing aadA2 and dfrA12. Thus, ESBL plasmids persisted in the farms with or without antimicrobial agent use. 相似文献
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Masako Nomaguchi Masaru Yokoyama Ken Kono Emi E. Nakayama Tatsuo Shioda Naoya Doi Sachi Fujiwara Akatsuki Saito Hirofumi Akari Kei Miyakawa Akihide Ryo Hirotaka Ode Yasumasa Iwatani Tomoyuki Miura Tatsuhiko Igarashi Hironori Sato Akio Adachi 《Journal of virology》2013,87(21):11447-11461
Human immunodeficiency virus type 1 (HIV-1) replication in macaque cells is restricted mainly by antiviral cellular APOBEC3, TRIM5α/TRIM5CypA, and tetherin proteins. For basic and clinical HIV-1/AIDS studies, efforts to construct macaque-tropic HIV-1 (HIV-1mt) have been made by us and others. Although rhesus macaques are commonly and successfully used as infection models, no HIV-1 derivatives suitable for in vivo rhesus research are available to date. In this study, to obtain novel HIV-1mt clones that are resistant to major restriction factors, we altered Gag and Vpu of our best HIV-1mt clone described previously. First, by sequence- and structure-guided mutagenesis, three amino acid residues in Gag-capsid (CA) (M94L/R98S/G114Q) were found to be responsible for viral growth enhancement in a macaque cell line. Results of in vitro TRIM5α susceptibility testing of HIV-1mt carrying these substitutions correlated well with the increased viral replication potential in macaque peripheral blood mononuclear cells (PBMCs) with different TRIM5 alleles, suggesting that the three amino acids in HIV-1mt CA are involved in the interaction with TRIM5α. Second, we replaced the transmembrane domain of Vpu of this clone with the corresponding region of simian immunodeficiency virus SIVgsn166 Vpu. The resultant clone, MN4/LSDQgtu, was able to antagonize macaque but not human tetherin, and its Vpu effectively functioned during viral replication in a macaque cell line. Notably, MN4/LSDQgtu grew comparably to SIVmac239 and much better than any of our other HIV-1mt clones in rhesus macaque PBMCs. In sum, MN4/LSDQgtu is the first HIV-1 derivative that exhibits resistance to the major restriction factors in rhesus macaque cells. 相似文献
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Yuki Matsushita Kei Sakamoto Yoshihiro Tamamura Yasuaki Shibata Tokutaro Minamizato Tasuku Kihara Masako Ito Ken-ichi Katsube Shuichi Hiraoka Haruhiko Koseki Kiyoshi Harada Akira Yamaguchi 《The Journal of biological chemistry》2013,288(27):19973-19985
CCN3, a member of the CCN protein family, inhibits osteoblast differentiation in vitro. However, the role of CCN3 in bone regeneration has not been well elucidated. In this study, we investigated the role of CCN3 in bone regeneration. We identified the Ccn3 gene by microarray analysis as a highly expressed gene at the early phase of bone regeneration in a mouse bone regeneration model. We confirmed the up-regulation of Ccn3 at the early phase of bone regeneration by RT-PCR, Western blot, and immunofluorescence analyses. Ccn3 transgenic mice, in which Ccn3 expression was driven by 2.3-kb Col1a1 promoter, showed osteopenia compared with wild-type mice, but Ccn3 knock-out mice showed no skeletal changes compared with wild-type mice. We analyzed the bone regeneration process in Ccn3 transgenic mice and Ccn3 knock-out mice by microcomputed tomography and histological analyses. Bone regeneration in Ccn3 knock-out mice was accelerated compared with that in wild-type mice. The mRNA expression levels of osteoblast-related genes (Runx2, Sp7, Col1a1, Alpl, and Bglap) in Ccn3 knock-out mice were up-regulated earlier than those in wild-type mice, as demonstrated by RT-PCR. Bone regeneration in Ccn3 transgenic mice showed no significant changes compared with that in wild-type mice. Phosphorylation of Smad1/5 was highly up-regulated at bone regeneration sites in Ccn3 KO mice compared with wild-type mice. These results indicate that CCN3 is up-regulated in the early phase of bone regeneration and acts as a negative regulator for bone regeneration. This study may contribute to the development of new strategies for bone regeneration therapy. 相似文献
67.
Tarô Adati Shinichi Kato Wataru Toriumi Kei Kawazu Wayan Susila Ketut Sumiartha Gede Suastika Dadang I Made Samudra 《Applied Entomology and Zoology》2013,48(2):113-118
The efficacy of synthetic female sex pheromone lures for Crocidolomia pavonana (Fabricius) (Lepidoptera: Crambidae) in the cabbage fields of Java and Bali, Indonesia, was investigated by varying the composition and dosage of the components. The lure containing a synthetic pheromone blend of (Z)-11-hexadecenyl acetate (Z11–16: Ac) and (Z)-9-tetradecenyl acetate (Z9–14: Ac) at a 10:1 ratio acquired significantly more male catches than single component lures and the control lure. Meanwhile, no attraction was observed when lures with 1:1 and 1:10 blends were tested. The composition of Z11–16: Ac and Z9–14: Ac at a ratio of 5, 10 and 20:1 attracted more males than the control lures. Dosage studies showed that 0.055 and 0.55 mg of a mixture of Z11–16: Ac and Z9–14: Ac (10:1 ratio) attracted more males than the control. These results are the first demonstration of the efficacy of synthetic pheromone for C. pavonana in field conditions. The present study suggests the feasibility of pheromone-based monitoring as a simple and low-cost technique for integrated pest management of this pest. 相似文献
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Takahiro Inoue Kyosuke Takao Takashi Yoshida Kei Wada Takashi Daifuku Yasuko Yoneda Keiichi Fukuyama Yoshihiko Sako 《Biochemical and biophysical research communications》2013
A unique [Ni–Fe–S] cluster (C-cluster) constitutes the active center of Ni-containing carbon monoxide dehydrogenases (CODHs). His261, which coordinates one of the Fe atoms with Cys295, is suggested to be the only residue required for Ni coordination in the C-cluster. To evaluate the role of Cys295, we constructed CODH-II variants. Ala substitution for the Cys295 substitution resulted in the decrease of Ni content and didn’t result in major change of Fe content. In addition, the substitution had no effect on the ability to assemble a full complement of [Fe–S] clusters. This strongly suggests Cys295 indirectly and His261 together affect Ni-coordination in the C-cluster. 相似文献
69.
Keisuke Yoshikawa Yoshihiro Kita Ayako Furukawa Noriko Kawamura Sanae Hasegawa-Ishii Yoichi Chiba Shiro Takei Kei Maruyama Takao Shimizu Atsuyoshi Shimada 《Prostaglandins, leukotrienes, and essential fatty acids》2013,88(5):373-381
Excitotoxicity is involved in neurodegenerative conditions. We investigated the pathological significance of a surge in prostaglandin production immediately after kainic acid (KA) administration [initial phase], followed by a sustained moderate elevation in prostaglandin level [late phase] in the hippocampus of juvenile rats. Numerous pyknotic hippocampal neurons were observed 72 h after KA treatment; this number remained elevated on days 10 and 30. Gross hippocampal atrophy was observed on days 10 and 30. Pre-treatment with indomethacin ameliorated neuronal death on days 10 and 30, and prevented hippocampal atrophy on day 30. Microglial response was moderated by the indomethacin pre-treatment. Blockade of only late-phase prostaglandin production by post-treatment with indomethacin ameliorated neuronal death on day 30. These findings suggest a role for initial-phase prostaglandin production in chronic progressive neuronal death, which is exacerbated by late-phase prostaglandin production. Blockade of prostaglandin production has therapeutic implications in preventing long-term neurological sequelae following excitotoxic brain damage. 相似文献
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Akira Yanai Keijiro Kato Teruhiko Beppu Kei Arima 《Bioscience, biotechnology, and biochemistry》2013,77(8):1505-1508
A practical method for preparing peptidoglycan from Ps. aeruginosa and E. coli was devised. After bacterial cells were dissolved in boiling 4% SDS solution, peptidoglycan was collected and washed with water by centrifugation. Peptidoglycan was treated further with pronase and lyophilized. The final preparation of peptidoglycan from Ps. aeruginosa appeared as a filmy coagulation in electron micrograph and its amino acid composition was determined as follows: Glu/Ala/A2pm/Mur/GlcN (100/183/104/61/98). The lysozyme digest showed the same pattern as that of E. coli peptidoglycan. N-Terminal analysis suggested that about half of the peptide chains was interbridged by the peptide bond between Ala and A2pm. The probable ratio of muropeptides in the peptidoglycan was estimated. 相似文献