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排序方式: 共有2917条查询结果,搜索用时 187 毫秒
1.
Takashi Ohnishi Yuki Ogawa Kota Suda Miki Komatsu Satoko Matsumoto Harmon Mitsuru Asukai Masahiko Takahata Norimasa Iwasaki Akio Minami 《International journal of molecular sciences》2021,22(9)
Pyogenic spondylodiscitis can cause severe osteolytic and destructive lesions in the spine. Elderly or immunocompromised individuals are particularly susceptible to infectious diseases; specifically, infections in the spine can impair the ability of the spine to support the trunk, causing patients to be bedridden, which can also severely affect the physical condition of patients. Although treatments for osteoporosis have been well studied, treatments for bone loss secondary to infection remain to be elucidated because they have pathological manifestations that are similar to but distinct from those of osteoporosis. Recently, we encountered a patient with severely osteolytic pyogenic spondylodiscitis who was treated with romosozumab and exhibited enhanced bone formation. Romosozumab stimulated canonical Wnt/β-catenin signaling, causing robust bone formation and the inhibition of bone resorption, which exceeded the bone loss secondary to infection. Bone loss due to infections involves the suppression of osteoblastogenesis by osteoblast apoptosis, which is induced by the nuclear factor-κB and mitogen-activated protein kinase pathways, and osteoclastogenesis with the receptor activator of the nuclear factor-κB ligand-receptor combination and subsequent activation of the nuclear factor of activated T cells cytoplasmic 1 and c-Fos. In this study, we review and discuss the molecular mechanisms of bone loss secondary to infection and analyze the efficacy of the medications for osteoporosis, focusing on romosozumab, teriparatide, denosumab, and bisphosphonates, in treating this pathological condition. 相似文献
2.
Kana Asano-Matsuda Sajida Ibrahim Tomoko Takano Jun Matsuda 《International journal of molecular sciences》2021,22(7)
The first step of urine formation is the selective filtration of the plasma into the urinary space at the kidney structure called the glomerulus. The filtration barrier of the glomerulus allows blood cells and large proteins such as albumin to be retained while eliminating the waste products of the body. The filtration barrier consists of three layers: fenestrated endothelial cells, glomerular basement membrane, and podocytes. Podocytes are specialized epithelial cells featured by numerous, actin-based projections called foot processes. Proteins on the foot process membrane are connected to the well-organized intracellular actin network. The Rho family of small GTPases (Rho GTPases) act as intracellular molecular switches. They tightly regulate actin dynamics and subsequent diverse cellular functions such as adhesion, migration, and spreading. Previous studies using podocyte-specific transgenic or knockout animal models have established that Rho GTPases are crucial for the podocyte health and barrier function. However, little attention has been paid regarding subcellular locations where distinct Rho GTPases contribute to specific functions. In the current review, we discuss cellular events involving the prototypical Rho GTPases (RhoA, Rac1, and Cdc42) in podocytes, with particular focus on the subcellular compartments where the signaling events occur. We also provide our synthesized views of the current understanding and propose future research directions. 相似文献
3.
Liu Yong-Fang Matsumoto Hiroshi Gu Ming Zhou Xiao-Xuan Wu Yong-Hua Chen Zhi-Hao 《核技术(英文版)》2019,30(7):1-6
Longitudinal injection is a promising on-axis injection scheme for diffraction-limited storage rings. In the latest version of the Hefei advanced light source(HALS), both the dynamic aperture and momentum aperture have been optimized. A longitudinal injection scheme was investigated on the HALS using a doublefrequency radio frequency system. To evaluate the injection performance, various errors were considered. A series of tracking simulations were conducted, and the injection efficiency was obtained under different error levels. 相似文献
4.
5.
Tomoko Okuyama Jun Shirakawa Kazuki Tajima Yoko Ino Heidrun Vethe Yu Togashi Mayu Kyohara Ryota Inoue Daisuke Miyashita Jinghe Li Nozomi Goto Taiga Ichikawa Shingo Yamasaki Haruka Ohnuma Rie Takayanagi Yayoi Kimura Hisashi Hirano Yasuo Terauchi 《International journal of molecular sciences》2020,21(21)
6.
Double‐network hydrogels were conveniently synthesized by the one‐shot radical polymerization of an ionic monomer for the first network and a non‐ionic monomer for the second network in the presence of crosslinkers by simultaneous addition of the monomers, that is, one‐shot and spontaneous two‐step polymerization accompanying the delay of polymerization of a second network monomer. We analyzed the polymerization process based on the conversion of each monomer during the reaction in the absence of crosslinkers. Then we fabricated the double‐network hydrogels using several polymerization systems consisting of a conjugated monomer and a non‐conjugated monomer in the presence of the dual crosslinkers. We analyzed the swelling, mechanical and viscoelastic properties of hydrogels synthesized by one‐shot radical polymerization to confirm the production mechanism and the network structure of the hydrogels. © 2020 Society of Chemical Industry 相似文献
7.
The reaction of N-(2,4-dinitrophenyl)pyridinium anion ( salt(A) ; A = Cl−, FeCl4−, and (CN)2N−) with linear polyethyleneimine (LPEI; Mn = 20 380) and branched polyethyleneimines (BPEI1; Mn = 600, BPEI2; Mn = 10 000) at various molar feed ratios without using a catalyst resulted in pyridinium ring opening to yield ionic LPEI and BPEIs that were crosslinked by conjugated penta-2,4-dienylideneammonium (PDA) units, LPEI-PDA , BPEI1-PDA , and BPEI2-PDA , respectively. A model compound was synthesized by the reaction of salt(Cl) with diethylamine. The solubilities of BPEI1-PDA and BPEI2-PDA depended on the feed ratios between salt(Cl) and BPEI1 or BPEI2. Dipping LPEI-PDA into water and methanol yielded hydro- and organogels, respectively. UV–vis and reflection measurements revealed an expanded π-conjugation length between the polymer chains due to the through-space orbital interaction of the electrons on the two nitrogen atoms at the crosslinked positions in LPEI-PDA , BPEI1-PDA , and BPEI2-PDA . Cyclic voltammetry analysis suggested that the polymers underwent electrochemical oxidation. Measurement using a superconducting quantum interference device (SQUID) indicated that LPEI-PDA having FeCl4− anions was paramagnetic. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020 , 137, 48712. 相似文献
8.
Trans‐fatty acid promotes thrombus formation in mice by aggravating antithrombogenic endothelial functions via Toll‐like receptors 下载免费PDF全文
Kensuke Kondo Tatsuro Ishida Tomoyuki Yasuda Hideto Nakajima Kenta Mori Nobuaki Tanaka Takeshige Mori Tomoko Monguchi Masakazu Shinohara Yasuhiro Irino Ryuji Toh Yoshiyuki Rikitake Kazunobu Kiyomizu Yoshiaki Tomiyama Junichiro Yamamoto Ken‐ichi Hirata 《Molecular nutrition & food research》2015,59(4):729-740
9.
Motoyasu Tanaka Kazuyuki Kon Mizuki Nakajima Nobutaka Matsumoto Shinnosuke Fukumura Kosuke Fukui 《Advanced Robotics》2020,34(2):70-88
AbstractIn this work, we develop an articulated mobile robot that can move in narrow spaces, climb stairs, gather information, and operate valves for plant disaster prevention. The robot can adopt a tall position using a folding arm and gather information using sensors mounted on the arm. In addition, this paper presents a stair climbing method using a single backward wave. This method enables the robot to climb stairs that have a short tread. The developed robot system is tested in a field test at the World Robot Summit 2018, and the lessons learned in the field test are discussed. 相似文献