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51.
Calmodulin‐like skin protein protects against spatial learning impairment in a mouse model of Alzheimer disease 下载免费PDF全文
Shinya Kusakari Mikiro Nawa Katsuko Sudo Masaaki Matsuoka 《Journal of neurochemistry》2018,144(2):218-233
52.
Involvement of thymus cells in the formation of germinal centers 总被引:2,自引:0,他引:2
53.
Functional characterization of the neuron‐restrictive silencer element in the human tryptophan hydroxylase 2 gene expression 下载免费PDF全文
54.
Epidermal growth factor signals attenuate phenotypic and functional development of neocortical GABA neurons 下载免费PDF全文
55.
N transfer in three-species grass-clover mixtures with chicory,ribwort plantain or caraway 总被引:1,自引:0,他引:1
Nawa Raj Dhamala Jim Rasmussen Georg Carlsson Karen Søegaard Jørgen Eriksen 《Plant and Soil》2017,413(1-2):217-230
Background and aims
There is substantial evidence that legume-derived Nitrogen (N) is transferred to neighboring non-legumes in grassland mixtures. However, there is sparse information about how deep rooted non-legume forage herbs (forbs) influence N transfer in multi-species grasslands.Methodology
Red clover (Trifolium pretense L.) was grown together with perennial ryegrass (Lolium perenne L.) and one of three forb species: chicory (Cichorium intybus L.), ribwort plantain (Plantago lanceolata L.) or caraway (Carum carvi L.) in a field experiment. During the first year after the establishment, red clover leaves were labeled with 15N-urea to determine the N transfer from red clover to companion ryegrass and forbs.Results
On an annual basis, up to 15 % of red clover N was transferred to the companion ryegrass and forbs, but predominantly to the grass. The forb species did not differ in their ability to take up clover N, but biomass production and soil N acquisition was higher in chicory and plantain than in caraway.Conclusions
Grass relied to a great extent on clover N, whereas forbs relied on soil N. Soil 15N-enrichment indicated that N transfer occurred in the upper soil layers and that a dependence on clover-derived N did not necessarily give grass a growth advantage.56.
Shiro Okumura Tetsuyuki Akao Satoko Yamashita Tokio Ichimatsu Kuniyo Inouye 《Cytotechnology》2005,47(1-3):59-67
Proteins of plasma membrane could be an index of purification of the plasma membrane of animal cells. A convenient method
is proposed for determining the plasma membrane proteins by a surface plasmon resonance (SPR) biosensor. Biotinylated proteins
were observed only in the peripheral areas of MOLT-4 cells which were treated by 5-[5-(N-succinimidyloxycarbonyl) pentylamido] hexyl-d-biotinamide. The proteins on HeLa cells were also biotinylated. And then the membrane samples of the HeLa cells were injected
onto the avidin-immobilized SPR-surface, and components bound non-specifically on the surface were removed by a washout solution.
The amount of biotinylated protein (BP) was determined directly from the absolute resonance unit (RU) after injection of the
washout solution. In the method a reference surface was not needed. The amount of BP bound to the surface was gradually attenuated
with the repeated injection, and a method for calibrating the RU value was introduced by considering the ratio of attenuation
by every injection. The correlation between the BP titer calculated by the calibration and the theoretically-estimated one
was greatly improved. Three cycles of the BP determination on a sensor surface was performed successfully. During the purification
process of membrane fractions, the degree of purification as judged by the BP titer was in good agreement with the degree
of increase in aminopeptidase N activity in the membrane fraction. Thus, the BP titer could be used as an index for purification
of plasma membrane. 相似文献
57.
Hiroshi Morita Yuichiro Tomizawa Jun Deguchi Tokio Ishikawa Hiroko Arai Kazumasa Zaima Takahiro Hosoya Yusuke Hirasawa Takayuki Matsumoto Katsuo Kamata Wiwied Ekasari Aty Widyawaruyanti Tutik Sri Wahyuni Noor Cholies Zaini Toshio Honda 《Bioorganic & medicinal chemistry》2009,17(24):8234-8240
Cassiarin A 1, a tricyclic alkaloid, isolated from the leaves of Cassia siamea (Leguminosae), shows powerful antimalarial activity against Plasmodium falciparum in vitro as well as P. berghei in vivo, which may be valuable leads for novel antimalarials. Interactions of parasitized red blood cells (pRBCs) with endothelium in aorta are especially important in the processes contribute to the pathogenesis of severe malaria. Nitric oxide (NO) reduces endothelial expression of receptors/adhesion molecules used by pRBC to adhere to vascular endothelium, and reduces cytoadherence of pRBC to vascular endothelium. Cassiarin A 1 showed vasorelaxation activity against rat aortic ring, which may be related with NO production. A series of a hydroxyl and a nitrogen-substituted derivatives and a dehydroxy derivative of 1 have been synthesized as having potent antimalarials against P. falciparum with vasodilator activity, which may reduce cytoadherence of pRBC to vascular endothelium. Cassiarin A 1 exhibited a potent antimalarial activity and a high selectivity index in vitro, suggesting that the presence of a hydroxyl and a nitrogen atom without any substituents may be important to show antimalarial activity. Relative to cassiarin A, a methoxy derivative showed more potent vasorelaxant activity, although it did not show improvement for inhibition of P. falciparum in vitro. These cassiarin derivatives may be promising candidates as antimalarials with different mode of actions. 相似文献
58.
Shinya Ohata Makiko Nawa Tokiwa Yamasaki Kenji Sawanobori Shoji Hata Yoichi Asaoka Hitoshi Okamoto Shuji Terai Toshiaki Katada 《Biochemical and biophysical research communications》2009,379(4):817-230
The fetal liver serves as the predominant hematopoietic organ until birth. However, the mechanisms underlying this link between hematopoiesis and hepatogenesis are unclear. Previously, we reported the isolation of a monoclonal antibody (anti-Liv8) that specifically recognizes an antigen (Liv8) present in murine fetal livers at embryonic day 11.5 (E11.5). Liv8 is a cell surface molecule expressed by hematopoietic cells in both fetal liver and adult mouse bone marrow. Here, we report that Liv8 is also transiently expressed by hepatoblasts at E11.5. Using protein purification and mass spectrometry, we have identified Liv8 as the CD44 protein. Interestingly, the expression of Liv8/CD44 in fetal liver was completely lost in AML1−/− murine embryos, which lack definitive hematopoiesis. These results show that hepatoblasts change from Liv8/CD44-negative to Liv8/CD44-positive status in a hematopoiesis-dependent manner by E11.5, and indicate that Liv8/CD44 expression is an important link between hematopoiesis and hepatogenesis during fetal liver development. 相似文献
59.
Takahashi M Kakita A Futamura T Watanabe Y Mizuno M Sakimura K Castren E Nabeshima T Someya T Nawa H 《Journal of neurochemistry》2006,99(3):770-780
Brain-derived neurotrophic factor (BDNF) is involved in synaptic development and plasticity, and alterations in BDNF expression or signaling are implicated in drug addiction and psychiatric diseases, such as depression and schizophrenia. In this study, we administered phencyclidine to postnatal and adult rats with different time schedules, and determined the correlations between BDNF expression and the behavioral effects. Both single and repeated phencyclidine injections into adult rats induced BDNF up-regulation in the corticolimbic system and a decrease in prepulse inhibition, both of which were transient. In contrast, subchronic postnatal administration increased BDNF protein and mRNA levels in the hippocampus and entorhinal cortex, which were sustained until 8 weeks of age. In parallel, the postnatal rats treated with phencyclidine developed a persistent decrease in prepulse inhibition at the adult stage. The chronic BDNF increase appeared to contribute to the prepulse inhibition abnormality, as subchronic BDNF infusion into the hippocampus of normal rats mimicked the prepulse inhibition deficits. This study suggests that phencyclidine exposure during brain development induces sustained BDNF up-regulation in the limbic system with a biological link to sensorimotor gating deficits. 相似文献
60.