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221.
BackgroundOsteoarthritis (OA) is a form of arthritis due to degradation of articular cartilage. OA is associated with stiffness, joint pain, and dysfunction, affecting adults worldwide. Galangin is a bioactive flavonoid that exerts several therapeutic and biological activities. Anti-hyperglycemic, anti-inflammatory, anti-cancer, and anti-apoptotic activities of galangin have been reported in several studies. In the present study, rats were divided into normal control, OA (control), galangin 10 mg/kg (low-dose), galangin 100 mg/kg (high-dose), and celecoxib 30 mg/kg (positive control) groups. All doses were administered orally for 14 consecutive days. The urinary type II collagen (µCTX-II) level as well as reactive oxygen species, tumor necrosis factor-alpha, interleukin-1 beta, interleukin-6, superoxide dismutase, catalase, lipid peroxidation, reduced glutathione, and glutathione peroxidase levels were measured. In addition, the CTX-II mRNA and protein expression levels were measured.ResultsGalangin supplementation significantly reduced the µCTX-II level compared with controls. Galangin treatment significantly reduced reactive oxygen species, lipid peroxidation, interleukin-1 beta, interleukin-6, and tumor necrosis factor-alpha levels, but increased catalase, superoxide dismutase, glutathione peroxidase, and reduced glutathione levels. Galangin treatment significantly reduced the CTX-II mRNA and protein expression levels. The low CTX-II level in tissue indicated the inhibition of cartilage degradation.ConclusionsIn summary, supplementation with galangin was effective against OA. The identification of potential therapeutic agents that inhibit inflammation may be useful for the management and prevention of OA.How to cite: Su Y, Shen L, Xue J, et al. Therapeutic evaluation of galangin on cartilage protection and analgesic activity in a rat model of osteoarthritis. Electron J Biotechnol 2021;53. https://doi.org/10.1016/j.ejbt.2021.05.005 相似文献
222.
Inspired by nature, improving photosensitization represents a vital direction for the development of artificial photosynthesis. The sensitization ability of photosensitizers (PSs) reflects in their electron-transfer ability, which highly depends on their excited-state lifetime and redox potential. Herein, for the first time, we put forward a facile strategy to improve sensitizing ability via finely tuning the excited state of Ru(II)-PSs (Ru-1–Ru-4) for efficient CO2 reduction. Remarkably, [Ru(Phen)2(3-pyrenylPhen)]2+ (Ru-3) exhibits the best sensitizing ability among Ru-1–Ru-4, over 17 times higher than that of typical Ru(Phen)32+. It can efficiently sensitize a dinuclear cobalt catalyst for CO2-to-CO conversion with a maximum turnover number of 66 480. Systematic investigations demonstrate that its long-lived excited state and suitable redox driving force greatly contributed to this superior sensitizing ability. This work provides a new insight into dramatically boosting photocatalytic CO2 reduction via improving photosensitization. 相似文献
223.
目的:通过研究运动及多巴胺Ⅱ型受体（dopamine type Ⅱ receptor,D2R）激动剂干预对PD模型小鼠纹状体D2MSN-D1MSN侧抑制效应的影响,揭示运动在改善PD小鼠基底神经节信息输出中的作用及机制。方法:选用4周龄雄性D2-Cre小鼠,右侧纹状体注射兴奋性光敏感蛋白病毒（rAAV-Ef1α-DIO-ChR2-EYFP-WPRE-pA）,通过光遗传技术精准操控D2MSN。小鼠随机分为对照组（D2-Cre）和模型组,纹状体分别注射生理盐水和神经毒素6-羟基多巴胺（6-Hydroxydopamine hydrobromide,6-OHDA）,经鉴定符合PD标准的模型组小鼠再分为PD组(PDD2-Cre)和PD运动组(PD+ExD2-Cre)。采用4周匀速跑台运动（18 m/min,40 min/天,连续5天/周）和D2R激动剂分别对各组小鼠进行干预。实验结束后,制备离体脑片,利用全细胞膜片钳结合光遗传技术检测各组小鼠纹状体D2MSN-D1MSN侧抑制效应及黑质网状部的信息输出,并验证侧抑制效应的变化是否由D2R介导。结果:光刺激D2-MSN后,D1-MSN动作电位发放个数PDD2-Cre组显著低于D2-Cre组（P<0.05）;PD+ExD2-Cre组显著高于PDD2-Cre组,但仍低于D2-Cre组（P<0.05）。光刺激D2-MSN诱发D1-MSN抑制性突触后电流（Optogenetic stimulation evoked inhibitory postsynaptic currents,oIPSC）的幅值与基线比值,PDD2-Cre组显著高于D2-Cre组（P<0.05）,PD+ExD2-Cre组显著低于PDD2-Cre组,但高于D2-Cre组（P<0.05）;光刺激D2-MSN诱发黑质网状部（SNr）抑制性突触后场电位（field inhibitory post synaptic potential,fIPSP）最大幅值,PDD2-Cre组显著低于D2-Cre组（P<0.05）,PD+ExD2-Cre组显著高于PDD2-Cre组,但低于D2-Cre组（P<0.05）。结论:PD模型小鼠纹状体D2MSN-D1MSN侧抑制效应异常,并影响了SNr的信息输出,这可能是导致PD基底神经节功能紊乱的重要原因之一。4周运动干预通过改善PD模型小鼠纹状体D2MSN-D1MSN侧抑制效应,调节了SNr的信息输出。D2R在运动改善PD小鼠纹状体D2MSN-D1MSN侧抑制效应和调节基底神经节信息输出中起重要作用。 相似文献
225.
林鸿 《金华职业技术学院学报》2002,(1)
合成了双苯甲酰丙酮缩乙二胺Schiff碱镍(II)配合物,并测定了该分子晶体结构。晶体属单斜晶系,空间群为P21/n,晶胞参数:a=10.793(2),b=7.909(2),c=22.025(4)A°,β=96.68(3)°,V=1867.4(7)A°3,Z=4,Dc=1.441g·cm-3。对于3494(I2σ(I))个可观察点,最终偏差因子R=0.0281,WR=0.0768。Schiff碱配体的四个配位原子犤O(1)、O(2)、N(1)和N(2)犦与Ni(II)配位,形成平面正方形NONi配位构型。 相似文献
226.
227.
介绍了一种简单易行的电能表数据采集器的设计方法,并且从硬件和软件两方面介绍设计方案.硬件核心采用TI公司的Cortex-M3处理器LM3S9b92. 相似文献
228.
Lina Klymenko 《Compare》2014,44(5):756-777
The main objective of this paper is to illustrate the conceptualisation of a textbook as a site of memory, a discourse and a genre. This paper investigates the semantic and linguistic elements of the discourse of World War II in Ukrainian school history textbooks for the 11th grade, centring on the following distinct key themes: the Molotov–Ribbentrop Pact, the German attack on the Soviet Union and the ensuing Nazi occupation regime, the Soviet army offensive followed by the restoration of the Soviet regime, and resistance movements. The textbooks analysed dismantle the Soviet myth of the Great Patriotic War and reveal the atrocities of Stalinism. They also create a new hero-and-victim paradigm: the heroic deeds of Ukrainians in the Soviet army and of the Organization of Ukrainian Nationalists (OUN) and the Ukrainian Insurgent Army (UPA) fighting for Ukraine’s independence are emphasised, as is the suffering of Ukrainians under the German occupation and the Stalinist regime. 相似文献
229.
实验是获取知识、培养创新思维和实践能力的重要渠道。本文强调了UGII在CAD／CAM技术课程实验教学中的作用,并主要介绍UGII在CAD／CAM各单元技术与集成技术的典型应用。 相似文献
230.
试论中日教科书里的日本二战小说--从文学批评的历史把握谈起 总被引：1，自引：0，他引：1
中日两国教科书里的日本二战小说在历史认识上所存在的偏差和作为教材所起到的负面作用值得注意。在日本,它们对青年一代二战史观的形成起着潜移默化的作用;在中国别导致对日本二战小说的误读,影响了从历史层面对日本侵华战争的总体把握。 相似文献