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41.
42.
Hyunsoo Kim Taesoo Kim Byung-Chul Jeong Il-Taeg Cho Daehee Han Noriko Takegahara Takako Negishi-Koga Hiroshi Takayanagi Jae Hee Lee Jai-Yoon Sul Vikram Prasad Seoung Hoon Lee Yongwon Choi 《Cell metabolism》2013,17(2):249-260
Highlights? Tmem64-deficient mice show increased bone volume ? Tmem64 deficiency reduces [Ca2+]i oscillation in response to RANKL stimulation ? Tmem64 interacts with SERCA2 ? Tmem64 positively regulates osteoclast formation via SERCA2/Ca2+ signaling 相似文献
43.
Takuya Matsushita Takahisa Tateishi Noriko Isobe Tomomi Yonekawa Ryo Yamasaki Dai Matsuse Hiroyuki Murai Jun-ichi Kira 《PloS one》2013,8(4)
Background
Differences in cytokine/chemokine profiles among patients with neuromyelitis optica (NMO), relapsing remitting multiple sclerosis (RRMS), and primary progressive MS (PPMS), and the relationships of these profiles with clinical and neuroimaging features are unclear. A greater understanding of these profiles may help in differential diagnosis.Methods/Principal Findings
We measured 27 cytokines/chemokines and growth factors in CSF collected from 20 patients with NMO, 26 with RRMS, nine with PPMS, and 18 with other non-inflammatory neurological diseases (OND) by multiplexed fluorescent bead-based immunoassay. Interleukin (IL)-17A, IL-6, CXCL8 and CXCL10 levels were significantly higher in NMO patients than in OND and RRMS patients at relapse, while granulocyte-colony stimulating factor (G-CSF) and CCL4 levels were significantly higher in NMO patients than in OND patients. In NMO patients, IL-6 and CXCL8 levels were positively correlated with disability and CSF protein concentration while IL-6, CXCL8, G-CSF, granulocyte-macrophage colony-stimulating factor (GM-CSF) and IFN-γ were positively correlated with CSF neutrophil counts at the time of sample collection. In RRMS patients, IL-6 levels were significantly higher than in OND patients at the relapse phase while CSF cell counts were negatively correlated with the levels of CCL2. Correlation coefficients of cytokines/chemokines in the relapse phase were significantly different in three combinations, IL-6 and GM-CSF, G-CSF and GM-CSF, and GM-CSF and IFN-γ, between RRMS and NMO/NMOSD patients. In PPMS patients, CCL4 and CXCL10 levels were significantly higher than in OND patients.Conclusions
Our findings suggest distinct cytokine/chemokine alterations in CSF exist among NMO, RRMS and PPMS. In NMO, over-expression of a cluster of Th17- and Th1-related proinflammatory cytokines/chemokines is characteristic, while in PPMS, increased CCL4 and CXCL10 levels may reflect on-going low grade T cell and macrophage/microglia inflammation in the central nervous system. In RRMS, only a mild elevation of proinflammatory cytokines/chemokines was detectable at relapse. 相似文献44.
Timothy W. Yu Maria H. Chahrour Michael E. Coulter Sarn Jiralerspong Kazuko Okamura-Ikeda Bulent Ataman Klaus Schmitz-Abe David A. Harmin Mazhar Adli Athar N. Malik Alissa M. D’Gama Elaine T. Lim Stephan J. Sanders Ganesh H. Mochida Jennifer N. Partlow Christine M. Sunu Jillian M. Felie Jacqueline Rodriguez Christopher A. Walsh 《Neuron》2013,77(2):259-273
45.
Relationships among the activities of enzymes related to photosynthesisand photorespiration, and 14CO2 photosynthetic products wereinvestigated with individual tobacco leaves attached to thestalk from the bottom to the top. P-glycolate phosphatase ofthe chloroplasts and glycolate oxidase of the peroxisomes hadtheir maximum activities in the 25th leaf from the dicotyledons.Maximum photorespiration was similarly distributed. The highestratio of serine-14C to glycine-14C in the photosynthesates andmaximum glycolate formation were also observed in the 25th leaf.Glutamateglyoxylate aminotransferase, serine hydroxymethyltransferaseand glycine decarboxylase were more active in the upper leaves.RuDP carboxylase had nearly constant activity in all leaves,except for the youngest in which activity decreased. MaximumCO2 photosynthesis and enzyme activity for the C4 dicarboxylicacid cycle occurred in the upper, youngest leaf. Distributionof photosynthetic CO2 fixation among the leaves did not coincidewith RuDP carboxylase activity. The photosynthetic capacityappeared to be better related to the distribution pattern forenzymes of the C4 dicarboxylic acid pathway, i.e. PEP carboxylase,pyruvate Pi dikinase and 3-PGA phosphatase in the upper leaves.The results suggest that the C4 dicarboxylic acid pathway participates,to some extent, in photosynthesis in young leaves of tobacco,a dicotyledonous plant.
1This work was reported at the Annual Meeting (1970) of theJapanese Plant Physiologists in Kobe.
2The Central Research Institute, Japan Monopoly Corporation1-28-3, Nishishinagawa, Shinagawaku, Tokyo, 141 Japan. (Received November 2, 1972; ) 相似文献
46.
Kensaku Maejima Masayoshi Hashimoto Yuka Hagiwara-Komoda Akio Miyazaki Masanobu Nishikawa Ryosuke Tokuda Kohei Kumita Noriko Maruyama Shigetou Namba Yasuyuki Yamaji 《Molecular Plant Pathology》2020,21(4):475-488
Plum pox virus (PPV) is one of the most important plant viruses causing serious economic losses. Thus far, strain typing based on the definition of 10 monophyletic strains with partially differentiable biological properties has been the sole approach used for epidemiological characterization of PPV. However, elucidating the genetic determinants underlying intra-strain biological variation among populations or isolates remains a relevant but unexamined aspect of the epidemiology of the virus. In this study, based on complete nucleotide sequence information of 210 Japanese and 47 non-Japanese isolates of the PPV-Dideron (D) strain, we identified five positively selected sites in the PPV-D genome. Among them, molecular studies showed that amino acid substitutions at position 2,635 in viral replicase correlate with viral titre and competitiveness at the systemic level, suggesting that amino acid position 2,635 is involved in aphid transmission efficiency and symptom severity. Estimation of ancestral genome sequences indicated that substitutions at amino acid position 2,635 were reversible and peculiar to one of two genetically distinct PPV-D populations in Japan. The reversible amino acid evolution probably contributes to the dissemination of the virus population. This study provides the first genomic insight into the evolutionary epidemiology of PPV based on intra-strain biological variation ascribed to positive selection. 相似文献
47.
Masato Ohtsuka Hiromi Miura Keiji Mochida Michiko Hirose Ayumi Hasegawa Atsuo Ogura Ryuta Mizutani Minoru Kimura Ayako Isotani Masahito Ikawa Masahiro Sato Channabasavaiah B Gurumurthy 《BMC genomics》2015,16(1)
Background
The pronuclear injection (PI) is the simplest and widely used method to generate transgenic (Tg) mice. Unfortunately, PI-based Tg mice show uncertain transgene expression due to random transgene insertion in the genome, usually with multiple copies. Thus, typically at least three or more Tg lines are produced by injecting over 200 zygotes and the best line/s among them are selected through laborious screening steps. Recently, we developed technologies using Cre-loxP system that allow targeted insertion of single-copy transgene into a predetermined locus through PI. We termed the method as PI-based Targeted Transgenesis (PITT). A similar method using PhiC31-attP/B system was reported subsequently.Results
Here, we developed an improved-PITT (i-PITT) method by combining Cre-loxP, PhiC31-attP/B and FLP-FRT systems directly under C57BL/6N inbred strain, unlike the mixed strain used in previous reports. The targeted Tg efficiency in the i-PITT typically ranged from 10 to 30%, with 47 and 62% in two of the sessions, which is by-far the best Tg rate reported. Furthermore, the system could generate multiple Tg mice simultaneously. We demonstrate that injection of up to three different Tg cassettes in a single injection session into as less as 181 zygotes resulted in production of all three separate Tg DNA containing targeted Tg mice.Conclusions
The i-PITT system offers several advantages compared to previous methods: multiplexing capability (i-PITT is the only targeted-transgenic method that is proven to generate multiple different transgenic lines simultaneously), very high efficiency of targeted-transgenesis (up to 62%), significantly reduces animal numbers in mouse-transgenesis and the system is developed under C57BL/6N strain, the most commonly used pure genetic background. Further, the i-PITT system is freely accessible to scientific community.Electronic supplementary material
The online version of this article (doi:10.1186/s12864-015-1432-5) contains supplementary material, which is available to authorized users. 相似文献48.
The brittle rachis character, which causes spontaneous shattering of spikelets, has an adaptive value in wild grass species. The loci Br1 and Br2 in durum wheat (Triticum durum Desf.) and Br3 in hexaploid wheat (T. aestivum L.) determine disarticulation of rachides above the junction of the rachilla with the rachis such that a fragment of rachis is attached below each spikelet. Using microsatellite markers, the loci Br1, Br2 and Br3 were mapped on the homoeologous group 3 chromosomes. The Br2 locus was located on the short arm of chromosome 3A and linked with the centromeric marker, Xgwm32, at a distance of 13.3 cM. The Br3 locus was located on the short arm of chromosome 3B and linked with the centromeric marker, Xgwm72 (at a distance of 14.2 cM). The Br1 locus was located on the short arm of chromosome 3D. The distance of Br1 from the centromeric marker Xgdm72 was 25.3 cM. Mapping the Br1, Br2 and Br3 loci of the brittle rachis suggests the homoeologous origin of these 3 loci for brittle rachides. Since the genes for brittle rachis have been retained in the gene pool of durum wheat, the more closely linked markers with the brittle rachis locus are required to select against brittle rachis genotypes and then to avoid yield loss in improved cultivars. 相似文献
49.
Kikkawa Y Yu H Genersch E Sanzen N Sekiguchi K Fässler R Campbell KP Talts JF Ekblom P 《Experimental cell research》2004,300(1):94-108
The presence of many laminin receptors of the beta1 integrin family on most cells makes it difficult to define the biological functions of other major laminin receptors such as integrin alpha6beta4 and dystroglycan. We therefore tested the binding of a beta1 integrin-null cell line GD25 to four different laminin variants. The cells were shown to produce dystroglycan, which based on affinity chromatography bound to laminin-1, -2/4, and -10/11, but not to laminin-5. The cells also expressed the integrin alpha6Abeta4A variant. GD25 beta1 integrin-null cells are known to bind poorly to laminin-1, but we demonstrate here that these cells bind avidly to laminin-2/4, -5, and -10/11. The initial binding at 20 min to each of these laminins could be inhibited by an integrin alpha6 antibody, but not by a dystroglycan antibody. Hence, integrin alpha6Abeta4A of GD25 cells was identified as a major receptor for initial GD25 cell adhesion to three out of four tested laminin isoforms. Remarkably, cell adhesion to laminin-5 failed to promote cell spreading, proliferation, and extracellular signal-regulated kinase (ERK) activation, whereas all these responses occurred in response to adhesion to laminin-2/4 or -10/11. The data establish GD25 cells as useful tools to define the role integrin alpha6Abeta4A and suggest that laminin isoforms have distinctly different capacities to promote cell adhesion and signaling via integrin alpha6Abeta4A. 相似文献
50.
Takeda Y Uoto K Iwahana M Jimbo T Nagata M Atsumi R Ono C Tanaka N Terasawa H Soga T 《Bioorganic & medicinal chemistry letters》2004,14(12):3209-3215
To improve the metabolic stability of 3, which exhibited both in vitro antitumor activity and in vivo efficacy by both iv and po administration, we designed and synthesized new taxane analogues. Most of the synthetic compounds maintained excellent antitumor activity and were scarcely metabolized by human liver microsomes. And some compounds exhibited potent antitumor effects against B16 melanoma BL6 in vivo by both iv and po administration similarly to 3. 相似文献