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51.
Tatsuya Nagano Hironori Edamatsu Kazuyuki Kobayashi Nobuyuki Takenaka Masatsugu Yamamoto Naoto Sasaki Yoshihiro Nishimura Tohru Kataoka 《PloS one》2014,9(9)
Background
Phospholipase Cε (PLCε) is an effector of Ras and Rap small GTPases and expressed in non-immune cells. It is well established that PLCε plays an important role in skin inflammation, such as that elicited by phorbol ester painting or ultraviolet irradiation and contact dermatitis that is mediated by T helper (Th) 1 cells, through upregulating inflammatory cytokine production by keratinocytes and dermal fibroblasts. However, little is known about whether PLCε is involved in regulation of inflammation in the respiratory system, such as Th2-cells-mediated allergic asthma.Methods
We prepared a mouse model of allergic asthma using PLCε +/+ mice and PLCε ΔX/ΔX mutant mice in which PLCε was catalytically-inactive. Mice with different PLCε genotypes were immunized with ovalbumin (OVA) followed by the challenge with an OVA-containing aerosol to induce asthmatic response, which was assessed by analyzing airway hyper-responsiveness, bronchoalveolar lavage fluids, inflammatory cytokine levels, and OVA-specific immunoglobulin (Ig) levels. Effects of PLCε genotype on cytokine production were also examined with primary-cultured bronchial epithelial cells.Results
After OVA challenge, the OVA-immunized PLCε ΔX/ΔX mice exhibited substantially attenuated airway hyper-responsiveness and broncial inflammation, which were accompanied by reduced Th2 cytokine content in the bronchoalveolar lavage fluids. In contrast, the serum levels of OVA-specific IgGs and IgE were not affected by the PLCε genotype, suggesting that sensitization was PLCε-independent. In the challenged mice, PLCε deficiency reduced proinflammatory cytokine production in the bronchial epithelial cells. Primary-cultured bronchial epithelial cells prepared from PLCε ΔX/ΔX mice showed attenuated pro-inflammatory cytokine production when stimulated with tumor necrosis factor-α, suggesting that reduced cytokine production in PLCε ΔX/ΔX mice was due to cell-autonomous effect of PLCε deficiency.Conclusions
PLCε plays an important role in the pathogenesis of bronchial asthma through upregulating inflammatory cytokine production by the bronchial epithelial cells. 相似文献52.
Unique Induction of CA1 LTP Components After Intake of Theanine, an Amino Acid in Tea Leaves and its Effect on Stress Response 总被引:1,自引:0,他引:1
Takeda A Tamano H Suzuki M Sakamoto K Oku N Yokogoshi H 《Cellular and molecular neurobiology》2012,32(1):41-48
Theanine, γ-glutamylethylamide, is one of the major amino acid components in green tea. This study was undertaken to evaluate
the effect of theanine intake on long-term potentiation (LTP) induction at hippocampal CA1 synapses and exposure to acute
stress. Young rats were fed water containing 0.3% theanine after birth. Key findings: Serum corticosterone level was markedly
decreased by theanine intake. Because this decrease can modify synaptic plasticity, the effect of theanine intake was examined
focused on CA1 LTP induction. CA1 LTP induced by a 100-Hz tetanus for 1 s was almost the same extent in hippocampal slices
from theanine-administered rats, whereas that induced by a 200-Hz tetanus for 1 s was significantly attenuated. 2-Amino-5-phosphonovalerate
(APV), an N-methyl-d-aspartate (NMDA) receptor antagonist, significantly attenuated CA1 LTP induced by a 200-Hz tetanus in the control rats, but
not in theanine-administered rats. Interestingly, APV completely blocked CA1 LTP induced by a 100-Hz tetanus in the control
rats, while scarcely blocking it in theanine-administered rats. These results indicate that theanine intake reduces NMDA receptor-dependent
CA1 LTP, while increasing NMDA receptor-independent CA1 LTP. Furthermore, neither 100-Hz tetanus-induced LTP nor 200-Hz tetanus-induced
LTP was attenuated in theanine-administered rats after exposure to tail suspension stress, suggesting that the lack of NMDA
receptor-dependent CA1 LTP by theanine intake is involved in ameliorating the attenuation of CA1 LTP after tail suspension.
This study is the first to indicate that theanine intake modifies the mechanism of CA1 LTP induction. 相似文献
53.
doi: 10.1111/j.1741‐2358.2011.00547.x Evaluation of newly developed devices for denture placement and removal in the dependent elderly Objective: The purpose of this study was to subjectively evaluate the utility of newly developed denture placement and removal devices. Objective observations were also made to support the evidence. Materials and method: Twenty‐one subjects were instructed to place and remove their dentures with and without the devices. We evaluated the device based on a questionnaire. Objective observations were based on a 2‐D image analysis. We analysed three factors: the time, the area and the circumference required to insert and remove the dentures. Results: Image analysis showed that the effectiveness and ease with which the subject used the device significantly improved with practice. The questionnaire data showed that a majority of the subjects appreciated the device after the first and second time. While there was no significant decrease in time required to place and remove dentures even with the device, the area and circumference of the movement on 2‐D images were significantly reduced. Conclusion: In this study, the utility of denture placement and removal devices was evaluated both subjectively and objectively. Our data reveal that the device is effective in the elderly. Further minor improvement in the device might be required to increase its effectiveness. 相似文献
54.
Kosenko A Kang S Smith IM Greene DL Langeberg LK Scott JD Hoshi N 《The EMBO journal》2012,31(14):3147-3156
Several neurotransmitters, including acetylcholine, regulate neuronal tone by suppressing a non-inactivating low-threshold voltage-gated potassium current generated by the M-channel. Agonist dependent control of the M-channel is mediated by calmodulin, activation of anchored protein kinase C (PKC), and depletion of the phospholipid messenger phosphatidylinositol 4,5-bisphosphate (PIP2). In this report, we show how this trio of second messenger responsive events acts synergistically and in a stepwise manner to suppress activity of the M-current. PKC phosphorylation of the KCNQ2 channel subunit induces dissociation of calmodulin from the M-channel complex. The calmodulin-deficient channel has a reduced affinity towards PIP2. This pathway enhances the effect of concomitant reduction of PIP2, which leads to disruption of the M-channel function. These findings clarify how a common lipid cofactor, such as PIP2, can selectively regulate ion channels. 相似文献
55.
Naoto Sugiura 《Plant Species Biology》2019,34(1):38-42
Bombus pseudobaicalensis queens are known pollinators of the threatened orchid Cypripedium macranthos var. rebunense. However, whether other bumblebee species also pollinate this orchid has not yet been ascertained. A 10-year observation provided convincing evidence that B. pseudobaicalensis is the only consistent pollinator. B. beaticola moshkarareppus queens were newly found to rarely carry pollen smears of the orchid, whereas B. hypocrita sapporoensis and B. diversus queens were practically mere flower visitors. Why these three species do not equal B. pseudobaicalensis in pollination effectiveness remains unclear but differences in body size and individual abundance between B. pseudobaicalensis and the other species are considered as possible primary causes. Given the almost complete dependence of C. macranthos var. rebunense on B. pseudobaicalensis for pollination and its potential risk, conservation managers should take care not to reduce the bumblebee colonies. 相似文献
56.
Yui T Taki N Sugiyama J Hayashi S 《International journal of biological macromolecules》2007,40(4):336-344
An exhaustive search of the crystal structure of beta-chitin was carried out by simultaneously optimizing all the structural parameters based on published X-ray diffraction data and stereochemical criteria. The most probable structure was characterized by a parallel-up chain polarity, a gg orientation of hydroxymethyl groups and an intermolecular hydrogen bond along the a-axis, which essentially reproduced the original structure proposed by Gardner and Blackwell. The proposed crystal structure was subsequently subjected to crystal modeling using the AMBER force field. The probable orientation of hydroxyl groups and their motional behaviors is proposed based on calculations for the crystal models identified. Solvated crystal models exhibited a slightly deformed structure with the formation of appreciable numbers of hydrogen bonds along the b-axis. 相似文献
57.
Haruo Hashimoto Tomoo Eto Tsutomu Kamisako Naoko Hoya Teruhiko Hatakeyama Toshiro Arai Makoto Yokosuka Yasuyuki Ohnishi Mamoru Ito Kyoji Hioki Ryo Suzuki Mitsuru Ohsugi Muneo Saito Yoshito Ueyama Toshimasa Yamauchi Naoto Kubota Kazuyuki Tobe Takashi Kadowaki Norikazu Tamaoki Tatsuji Nomura Kinori Kosaka 《Experimental Animals》2008,57(4):407-411
Efficient reproduction using natural mating and reproduction technology [in vitro fertilization (IVF) and embryo transfer (ET)] was investigated in IRS2 deficient mice with C57BL/6JJcl genetic background (Irs2(-/-) mice) as a typical type 2 diabetes model. From the results using various combinations of Irs2(-/-) and Irs2(-/+) mice, the combination of female Irs2(-/+) x male Irs2(-/-) was found to be more efficient than other combinations. In applications of reproduction technology using IVF and ET, the combination of female Irs2(-/+) x male Irs2(-/-) involves the possibility of Irs2(-/-) production by repeats using female Irs2(-/+) mice. However, reproductive continuity using this combination is difficult because of dependence on human technique and the cost of ET. Therefore, we concluded that Irs2(-/-) mice should be produced by embryo transfer using Irs2(-/-) mice from a colony consisting of female Irs2(-/+) x male Irs2(-/-). 相似文献
58.
59.
Maruyama S Miyajima N Bohgaki M Tsukiyama T Shigemura M Nonomura K Hatakeyama S 《Molecular and cellular biochemistry》2008,307(1-2):73-82
Ubiquitylation appears to be involved in the membrane trafficking system including endocytosis, exocytosis, and ER-to-Golgi
transport. We found that PIRH2, which was identified as an interacting protein for androgen receptor or p53, interacts with
and ubiquitylates the ε-subunit of coatmer complex, ε-COP. PIRH2 promotes the ubiquitylation of ε-COP in vitro and in vivo
and consequently promotes the degradation of ε-COP. The interaction between PIRH2 and ε-COP is affected by the presence of
androgen, and PIRH2 in the presence of androgen promotes ubiquitylation of ε-COP in vivo. Furthermore, overexpression of the
wild type of PIRH2 in prostate cancer cells causes downregulation of the secretion of prostate-specific antigen (PSA), a secretory
protein in prostate epithelial cells and one of diagnostic markers for prostate cancer. Our results indicate that PIRH2 functions
as a regulator for COP I complex. 相似文献