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1.
目的探讨关节镜下半月板成形术(AMP)对膝关节半月板损伤患者血清疼痛因子、一氧化氮(NO)、透明质酸(HA)及关节活动度的影响。方法选取2019年5月—2020年12月收治的90例膝关节半月板损伤为研究对象,根据治疗方法不同分为对照组和治疗组,每组45例。对照组接受保守治疗,治疗组行AMP治疗。比较两组的临床疗效,治疗前后的血清前列腺素E2(PGE2)、5-羟色胺(5-HT)、NO、HA、疼痛视觉模拟评分法(VAS)评分和膝关节活动度。记录两组治疗并发症发生情况。结果治疗组疗效优良率高于对照组(P<0.05)。治疗后,两组血清PGE2、5-HT、NO、HA水平均较治疗前下降,且治疗组低于对照组(P<0.05)。治疗后1、2、3、4周,两组VAS评分均较治疗前降低,且治疗组低于对照组(P<0.05)。治疗后,两组膝关节屈伸活动度均较治疗前升高,且治疗组高于对照组(P<0.05)。两组并发症发生率比较差异无统计学意义(P>0.05)。结论AMP对膝关节半月板损伤疗效良好,可减少疼痛因子生成,控制NO、HA水平,提高关节活动度。  相似文献   
2.
Recently, we reported that titanium dioxide (TiO2) materials activated endothelial cells via Kruppel-like factor (KLF)-mediated nitric oxide (NO) dysfunction, but the roles of physical properties of materials are not clear. In this study, we prepared nanobelts from P25 particles and compared their adverse effects to human umbilical vein endothelial cells (HUVECs). TiO2 nanobelts had belt-like morphology but comparable surface areas as P25 particles. When applied to HUVECs, P25 particles or nanobelts did not induce cytotoxicity, although nanobelts were much more effective to increase intracellular Ti element concentrations compared the same amounts of P25 particles. Only nanobelts significantly induced THP-1 adhesion onto HUVECs. Consistently, nanobelts were more significant to induce the expression of intracellular adhesion molecule-1 (ICAM1) and the release of soluble ICAM-1 (sICAM-1), indicating that nanobelts were more potent to induce endothelial activation in vitro. As the mechanisms for endothelial activation, both P25 and nanobelts reduced the generation of intracellular NO as well as the expression of NO regulators KLF2 and KLF4. Combined, the results from this study indicated that the different morphologies of P25 particles and nanobelts only changed their internalization into HUVECs but showed minimal impact on KLF-mediated NO signaling pathways.  相似文献   
3.
目的:探讨尿酸性肾病中医分型与氧化应激相关性。方法:采用回顾性分析方法对2017年12月至2019年9月北京中医药大学第三附属医院收治的尿酸性肾病患者105例进行研究,选择同时期正常健康者105例作为对照,参考《中药新药临床研究指导原则》将105例尿酸性肾病和临床常见证型相结合,分成脾肾气虚18例、气阴两虚证19例、肝肾阴虚16例、阴阳两虚12例、湿热蕴结19例、瘀血阻滞17例、痰浊内阻13例,均在入院次日清晨空腹抽取静脉血,检测氧化应激氧化应激、肾功能损害指标,比较不同组别在氧化应激指标含量水平变化情况,比较中医分型和氧化应激、肾功能损害指标水平变化。结果:1)尿酸性肾病组总抗氧化能力(T-ACO)、晚期蛋白氧化物(AOPP)、血清丙二醇(MDA)、超氧化物歧化酶(SOD)含量水平分别为(19.45±3.42)U/mL、(42.45±3.53)μmol/L、(4.52±1.23)nmol/L、(76.78±5.64)U/mL,正常对照组则分别为(10.76±1.31)U/mL、(20.84±1.28)μmol/L、(2.13±0.76)nmol/L、(130.85±16.75)U/mL,尿酸性肾病组T-ACO、AOPP、MDA较正常对照组显著偏高,SOD显著偏低(P<0.05)。2)虚证中阴阳两虚证SOD含量上较其他证型均偏低,而MDA、T-AOC、AOPP、胱抑素C(CysC)、β2微球蛋白、尿微量白蛋白(UMALB)、蛋白尿发生率则较其他证型均偏高,差异均有统计学意义(P<0.05),实证中瘀血阻滞证SOD含量较其他证型均偏低,而MDA、T-AOC、AOPP则较其他证型均偏高,差异均有统计学意义(P<0.05)。结论:尿酸性肾病中医分型的阴阳两虚证、瘀血阻滞证氧化应激水平、肾损害指标均显著升高,可结合该实验室检查进行临床干预。  相似文献   
4.
Macrophages are the most abundant immune cells in the lung, which play an important role in COPD. The anti-inflammatory and anti-oxidation of ergosterol are well documented. However, the effect of ergosterol on macrophage polarization has not been studied. The objective of this work was to investigate the effect of ergosterol on macrophage polarization in CSE-induced RAW264.7 cells and Sprague-Dawley (SD) rats COPD model. Our results demonstrate that CSE-induced macrophages tend to the M1 polarization via increasing ROS, IL-6 and TNF-α, as well as increasing MMP-9 to destroy the lung construction in both RAW264.7 cells and SD rats. However, treatment of RAW264.7 cells and SD rats with ergosterol inhibited CSE-induced inflammatory by decreasing ROS, IL-6 and TNF-α, and increasing IL-10 and TGF-β, shuffling the dynamic polarization of macrophages from M1 to M2 both in vitro and in vivo. Ergosterol also decreased the expression of M1 marker CD40, while increased that of M2 marker CD163. Moreover, ergosterol improved the lung characters in rats by decreasing MMP-9. Furthermore, ergosterol elevated HDAC3 activation and suppressed P300/CBP and PCAF activation as well as acetyl NF-κB/p65 and IKKβ, demonstrating that HDAC3 deacetylation was involved in the effect of ergosterol on macrophage polarization. These results also provide a proof in immunoregulation of ergosterol for therapeutic effects of cultured C. sinensis on COPD patients.  相似文献   
5.
目的:观察肺癌患者放疗后一氧化氮分数(FeNO)的增加能否提示放射性肺损伤。方法:本研究中,我们评估了FeNO变化与放疗后呼吸症状、CT扫描改变和剂量体积直方图(DVH)参数之间的关系。测量65例肺癌患者放疗前及放疗后4、5、6、10周和4、7.5月的FeNO。结果:在放疗后,11名肺癌患者(17%)自述有明显的呼吸道症状,21名(32%)患者有超过1/3的被照射肺区表现出放射性肺炎样图像。13名患者(20%)的FeNO增加超过10 ppb。以FeNO增加超过10 ppb为标准诊断放疗相关呼吸症状的灵敏度和特异性分别为18%和83%。FeNO变化与放疗后DVH参数或CT扫描改变之间无显著相关性。3名患者(5%)在第4、5周持续表现出异常高水平的FeNO(2或3倍,高达55 ppb),随后出现了显著的呼吸症状和/或放射性肺炎图像。结论:放疗期间的连续FeNO监测预测肺癌患者放射性肺炎症状或图像的能力较差。然而,三名患者表现出的特定模式值得研究。  相似文献   
6.
Benzodiazepines are usually prescribed for anxiety and sleep disorders in long‐term schedules that may cause drug dependence. Discontinuation after prolonged administration may lead to withdrawal expression, being anxiety the most predominant sign. The context‐dependent associative learning process that underlies diazepam dependence can be interfered by pre‐exposure to the drug administration context, an effect known as latent inhibition. Considering this background, the primary aim of the present investigation is to develop a therapeutic strategy to prevent diazepam withdrawal in male Wistar rats by interfering with this learning process. Nitric oxide is a crucial player in learning and memory, hippocampal synaptic transmission and in diazepam withdrawal. Then, a secondary goal is to determine how latent inhibition could alter functional plasticity and neuronal nitric oxide synthase enzyme (NOS‐1) expression within the hippocampus, by using multi‐unitary cell recordings and Western blot, respectively. Our results indicate that chronic diazepam treated animals under latent inhibition did not show anxiety, or changes in hippocampal synaptic transmission, but a significant reduction in NOS‐1 expression was observed. Accordingly, pharmacological NOS‐1 inhibition resembles behavioral and electrophysiological changes induced by latent inhibition. Contrary, diazepam treated animals under Control protocol expressed anxiety and evidenced an increased hippocampal‐plasticity, without alterations in NOS‐1 expression. In conclusion, manipulation of the contextual cues presented during diazepam administration may be considered as an effective non‐pharmacological tool to prevent the withdrawal syndrome. This behavioral strategy may influence hippocampal synaptic transmission, probably by alterations in nitric oxide signaling pathways in this structure.  相似文献   
7.
ObjectivePrevious studies have shown that hydrogen sulfide (H2S) exerts potent proangiogenic properties under in vitro conditions and in rodent models. We sought to determine whether a novel H2S prodrug promotes peripheral revascularization in a swine model of acute limb ischemia (ALI).MethodsALI was induced in 17 female miniswine via intravascular occlusion of the external iliac. At day 7 after ALI induction, miniswine (n = 17) were randomized to received placebo or the H2S prodrug, SG-1002 (800 mg per os twice a day), for 35 days. At day 35 SG-1002 increased circulating levels of H2S (5.0 ± 1.2 μmol/L vs 1.8 ± 0.50 μmol/L; P < .05), sulfane sulfur (10.6 ± 2.3 μmol/L vs 2.6 ± 0.8 μmol/L; P < .05), and nitrite (0.5 ± 0.05 μmol/L vs 0.3 ± 0.03 μmol/L; P < .005) compared with placebo. SG-1002 therapy increased angiographic scoring in ischemic limb vessel number (27.6 ± 1.6 vs 22.2 ± 1.8; P < .05) compared with placebo. Treatment with SG-1002 preserved existing capillaries in ischemic limbs (128.3 ± 18.7 capillaries/mm2 vs 79.0 ± 9.8 capillaries/mm2; P < .05) compared with placebo. Interestingly, treatment with SG-1002 also improved coronary vasorelaxation responses to bradykinin and substance P in miniswine with ALI.ConclusionsOur results suggest that daily administration of the H2S prodrug, SG-1002, leads to an increase in circulating H2S and nitric oxide signaling and preserves vessel number and density in ischemic limbs. Furthermore, SG-1002 therapy improved endothelial-dependent coronary artery vasorelaxation in the setting of ALI. Our data demonstrate that SG-1002 preserves the vascular architecture in ischemic limbs and exerts vascular protective effects in the coronary vasculature in a model of peripheral vascular disease.  相似文献   
8.
目的 探讨口服硝酸盐对大鼠背部随意皮瓣的影响,以硝酸盐-亚硝酸盐-NO通路为切入点,探讨其可能的机制。方法 将24只雄性Wistar大鼠随机分为硝酸盐组、氯化钠组和对照组,每组8只。采用改良大鼠背部随意皮瓣制作方法造模。硝酸盐干预组在术前7 d及术后每天口服0.5 mmol/L硝酸钠,氯化钠组每天口服等量氯化钠,对照组每天口服蒸馏水。术后第7天,检测各组皮瓣的存活情况,大鼠血清中硝酸盐、亚硝酸盐、肿瘤坏死因子(tumor necrosis factor alpha,TNF-a)和白介素6(interleukin-6,IL-6)水平,以及皮瓣组织中超氧化物歧化酶(superoxide dismutase,SOD)和丙二醛(malondialdehyde,MDA)水平。采用SPSS 20.0软件包对数据进行t检验。结果 硝酸盐组皮瓣的存活面积显著高于对照组(P<0.05)。H-E染色显示,硝酸盐明显减轻了皮瓣的组织学损伤。硝酸钠显著增加了血清中硝酸盐和亚硝酸盐水平(P<0.05),并显著下调血清中TNF-a和IL-6水平(P<0.05)。此外,硝酸盐组皮瓣组织内MDA表达显著减少(P<0.05),SOD表达显著增加(P<0.05)。结论 口服硝酸盐可通过调控皮瓣的氧化应激和炎症反应保护皮瓣。  相似文献   
9.
10.
《Vaccine》2021,39(29):3862-3870
Bacillus anthracis, the causative agent of anthrax, continues to be a prominent biological warfare and bioterrorism threat. Vaccination is likely to remain the most effective and user-friendly public health measure to counter this threat in the foreseeable future. The commercially available AVA BioThrax vaccine has a number of shortcomings where improvement would lead to a more practical and effective vaccine for use in the case of an exposure event. Identification of more effective adjuvants and novel delivery platforms is necessary to improve not only the effectiveness of the anthrax vaccine, but also enhance its shelf stability and ease-of-use. Polyanhydride particles have proven to be an effective platform at adjuvanting the vaccine-associated adaptive immune response as well as enhancing stability of encapsulated antigens. Another class of adjuvants, the STING pathway-targeting cyclic dinucleotides, have proven to be uniquely effective at inducing a beneficial inflammatory response that leads to the rapid induction of high titer antibodies post-vaccination capable of providing protection against bacterial pathogens. In this work, we evaluate the individual contributions of cyclic di-GMP (CDG), polyanhydride nanoparticles, and a combination thereof towards inducing neutralizing antibody (nAb) against the secreted protective antigen (PA) from B. anthracis. Our results show that the combination nanovaccine elicited rapid, high titer, and neutralizing IgG anti-PA antibody following single dose immunization that persisted for at least 108 DPI.  相似文献   
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