一氧化氮及一氧化氮合酶在哮喘大鼠气道高反应中的作用

目的：探讨一氧化氮及一氧化氮合酶(nitric oxide synthase，NOS)在哮喘大鼠气道炎症中的作用及激素对其活性的影响，以期为该病的预防、康复措施介入提供理论依据。方法：实验选用雄性豚鼠30只，按随机数字法将豚鼠分为3组：①哮喘组：用100g／L卵蛋白腹腔注射1mL致敏，2周后用10g／L卵蛋白超声雾化吸入致其哮喘发作。②激素组：诱喘同前，每次诱喘前腹腔内注射甲基强的松龙10mg／kg。③对照组：用生理盐水代替诱喘剂。每组分别测定其血浆和肺组织NO2^-／NO3^-水平、肺组织诱导型NOS(inducible nitric oxide synthase，iNOS)和原生型NOS(constitute nitric oxide synthase，cNOS)活性水平，并用组织化学染色法观察NOS在豚鼠哮喘模型肺组织中的分布。结果：3组豚鼠血浆NO2^-／NO3^-水平差异无显著性意义(P&;gt;0．05)，哮喘组肺组织中NO2^-／NO3^-和iNOS活性水平[(0．87&;#177;0．08)μmol／g，(56&;#177;14)nmol／g]明显高于对照组和激素组[(0．19&;#177;0．06)μmol／g，(12&;#177;6)mnol／g；(0．18&;#177;0．07)μmol／g，(12&;#177;5)nmol／g](P&;lt;0．01)。对照组肺组织化学方法显示的阳性产物呈蓝色沉淀，主要分布于各级支气管上皮细胞，哮喘组及激素组阳性产物变化不明显。哮喘组肺组织iNOS活性水平和肺组织NO2^-／NO3^-水平呈高度正相关(r=0．782．P&;lt;0．05)。结论：一氧化氮可引起气道高反应性而导致和(或)加重哮喘发病。用甲基强的松龙治疗哮喘可减轻气道炎症，使哮喘大鼠肺组织中iNOS表达降低。     

雾化吸入氯胺酮对哮喘大鼠肺组织一氧化氮及一氧化氮合酶的影响

目的通过建立大鼠支气管哮喘模型,观察不同浓度氯胺酮对哮喘大鼠肺组织iNOS活性及NO含量的影响。方法SD大鼠随机分成对照组(N组)、哮喘模型组(A组)、不同浓度氯胺酮预处理组(分别为K1组、K2组)和地塞米松组(D组),每组8只。A组大鼠用卵白蛋白辅以百日咳杆菌菌苗和氢氧化铝为佐剂注射致敏,2周后雾化吸入卵蛋白激发哮喘;氯胺酮处理组大鼠用同样方法致敏,但在激发前分别给予雾化吸入氯胺酮25 g/L(K1组)和50 g/L(K2组);D组在激发前给予雾化吸入0.01%地塞米松;N组用生理盐水替代卵蛋白进行注射和吸入。每组分别测定其肺组织NO2-/NO3-水平、肺组织诱导型NOS(iNOS)和原生型NOS(cNOS)活性水平,并用免疫组织化学法观察iNOS在大鼠哮喘模型肺组织中的分布。结果A组肺组织中NO2-/NO3-和iNOS水平升高,iNOS和肺组织NO2-/NO3-水平呈高度正相关;K1、K2组肺组织中NO2-/NO3-和iNOS水平低于A组(P<0.05);D组肺组织中NO2-/NO3-和iNOS水平亦低于A组(P<0.05)。结论25 g/L或50 g/L的氯胺酮雾化吸入可抑制哮喘大鼠肺组织iNOS活性,降低NO含量,减轻大鼠肺部炎症。     

参麻益智胶囊对痴呆大鼠一氧化氮和一氧化氮合酶的影响

目的:证实参麻益胶囊治疗血管性痴呆的药效以及探讨其作用机制。方法:采用颈内动脉注射同种大鼠微血栓悬液制作大鼠血管痴呆(多发性脑梗死)动物模型,设立参麻益智胶囊高、中、低剂量组和阳性药、模型及正常对照组,连续给药6周后,测定血浆、脑组织的一氧化氮含量及一氧化氮合酶(NOS)活性。结果:①模型对照组大鼠血浆中的一氧化氮含量(71.6±24.3)μmol/L和NOS活性(135.9±35.8)nmol/(L·s)明显高于正常对照组(45.5±17.0)μmol/L和(59.3±32.2)nmol/(L·s),P<0.01。②模型对照组大鼠脑组织中的一氧化氮含量(261.0±30.0)μmol/g和NOS活性(66.8±7.2)nmol/(g·s)明显高于正常对照组(191±39)μmol/g和(52.2±2.8)nmol/(g·s),P<0.05。③参麻益智胶囊高、中、低剂量组大鼠血浆中的一氧化氮含量分别为(52.6±15.3),(56.0±17.9),(56.3±12.3)μmol/L和NOS活性(71.9±31.2),(99.7±26.5),(93.0±35.7)nmol/(L·s)明显低于模型对照组(P<0.01)。④参麻益智胶囊高、中、低剂量组大鼠脑组织中的一氧化氮含量和NOS活性明显低于模型对照组(P<0.01)。结论:参麻益智胶囊可降低血管性痴呆大鼠血浆、脑组织中一氧化氮含量及NOS活性。     

电针对癫痫大鼠脑组织及肝脏的一氧化氮和一氧化氮合酶含量的影响

目的:探讨电针对癫痫大鼠脑组织和肝组织中一氧化氮,一氧化氮合酶(nitricoxidesyntheses,NOS)的影响,以及电针治疗癫痫的可能机制。方法∶实验于2004-03/10在南京中医药大学第二临床医学院实验室完成。选择SD大鼠40只,随机分成为正常组、模型组、电针组、假针刺组,每组10只。采用比色法测定对癫痫造模大鼠的一氧化氮,NOS和一氧化氮/NOS比值进行随机对照分析性研究。结果∶模型组脑一氧化氮犤(19.76±2.66)μmol/L犦,NOS犤(498.8±94.7)nkat/g犦和一氧化氮/NOS比值(1.38±0.46)明显高于正常组(P<0.05),电针组脑一氧化氮犤(6.04±3.52)μmol/L犦,NOS犤(203.9±102.2)nkat/g犦和一氧化氮/NOS比值(1.00±0.57)明显低于模型组(P<0.05),假针刺组一氧化氮,NOS和一氧化氮/NOS含量不明显变化。肝组织中各项因子变化与脑组织中变化一致。结论∶电针对癫痫大鼠的一氧化氮,NOS和一氧化氮/NOS有显著的抑制调节作用。这可能是电针治疗癫痫临床取得疗效的重要机制之一。     

游泳对慢性低氧高二氧化碳大鼠一氧化氮代谢的影响

背景运动锻炼能提高正常机体和心血管疾病患者血管一氧化氮的生成能力,但运动锻炼对慢性低氧时一氧化氮代谢有积极的影响.目的探讨游泳锻炼对慢性低氧高二氧化碳大鼠一氧化氮代谢及肺动脉平均压(mean pulmonary artery pressuse,mPAP)的影响.设计随机对照的实验研究.地点、材料和干预实验在温州医学院肺心病研究室完成.实验选用31只SD大鼠随机分成正常对照组(10只)与模型组(21只).模型组低氧4周后,又随机分为模型对照组(8只)与游泳锻炼组(13只).采用比色法测定血浆、肺组织、右心室组织一氧化氮代谢产物(NO2-/NO3-)的含量,液体闪烁仪测定[3H]-瓜氨酸的生成量,计算肺组织、右心室组织组织型NOS(tissue NOS,tNOS)、诱导型NOS(induced NOS,iNOS)和原生型NOS(constitutive NOS,cNOS)的活性.主要观察指标游泳对慢性低氧高二氧化碳在大鼠mPAP、右心室质量,血浆、肺组织、右心室组织NO2-/NO3-含量、NOS活性的影响.结果游泳锻炼组的血浆、肺与右心室组织的NO2-/NO3-的含量和cNOS的活性明显高于模型对照组;同时,游泳锻炼组的mPAP[(19.62±1.32)mm Hg]显著低于模型对照组[(15.19±1.11)mm Hg](q=12.632,P＜0.01).结论游泳锻炼有促使一氧化氮生成增加和降低肺动脉压的作用.     

新生儿缺氧缺血性脑病血浆一氧化氮及一氧化氮合成酶水平对预后判断的意义

目的探讨新生儿缺氧缺血性脑病 (hypoxic-ischemic encephalopathy , HIE)时一氧化氮、一氧化氮合成酶 (Nitrogen monoxide synthase , NOS)水平的变化及其对预后判断及恢复期指导的意义. 方法 采用比色等方法测定 32例 HIE患儿及 30例正常新生儿血浆一氧化氮、一氧化氮合成酶活性水平. 结果 正常对照组一氧化氮、 NOS水平分别为 (72.84± 12.35) μ mol/L和 (0.203± 0.05) kU/g, HIE组为 (129.80± 32.66) μ mol/L和 (0.352± 0.124) kU/g;其中轻度 HIE为 (105.65± 36.30) μ mol/L和 (0.289± 0.09) U/mg;中度 HIE为 (135.03± 24.40) μ mol/L和 (0.325± 0.16) kU/g;重度 HIE组为 (144.55± 26.32) μ mol/L和 (0.364± 0.01) kU/g. HIE急性期一氧化氮、 NOS水平校正常新生儿明显升高 (t=- 8.97, P< 0.01),中、重度 HIE升高更显著 (t=- 10.62,- 12.01,P< 0.01),中、重度 HIE患儿较轻度 HIE患儿升高明显 (t=- 2.12,- 2.92,P< 0.05,P< 0.01).中、重度 HIE之间则无明显差别. 结论一氧化氮、 NOS水平高低与 HIE患儿脑损伤程度和预后有关,可作为判断 HIE患儿病情恢复及预后的指标之一.     

银杏叶片对高原人体运动后一氧化氮及一氧化氮合酶的影响

目的:缺氧会对机体造成多种损伤,探讨银杏叶片、酪氨酸冲剂和红景天对高原人体力竭运动一氧化氮及一氧化氮合酶(nitricoxidesynthase,NOS)的影响,以减轻和预防缺氧对机体的损伤。方法:对进驻海拔3700m高原半年的30名健康青年随机分为银杏叶片组、红景天组和酪氨酸组,每组10人。在未服药时、服药后第15天分别采用功率自行车进行渐增负荷运动至力竭,测定血清中一氧化氮、NOS含量。结果:各组受试者运动后较安静时一氧化氮犤银杏叶片组(101.4±13.7)μmol/L,(67.4±12.2)μmol/L;红景天组(98.8±13.4)μmol/L,(66.7±13.0)μmol/L;酪氨酸组(95.1±13.5)μmol/L,(66.9±12.5)μmol/L犦及NOS犤银杏叶片组(69.9±10.7)U/mL,(43.2±3.8)U/mL;红景天组(67.6±11.0)U/mL,(43.5±4.63)U/mL;酪氨酸组(65.7±10.2)U/mL,(42.9±3.98)U/mL犦均增高,差异有显著性意义(P<0.05或P<0.01)。服药后较服药前一氧化氮增高,差异有非常显著性意义(P<0.01),NOS增高,差异有显著性意义(P<0.05)。结论:银杏叶片、酪氨酸冲剂和红景天均能增强高原运动时NOS活性,使一氧化氮合成增加,可减轻和预防缺氧会对机体造成多种损伤。     

海马长时程增强中一氧化氮变化与L型钙通道和神经细胞黏附分子的关系

目的:了解离体海马脑片CA1区突触传递长时程增强(longtermpoten-tiation,LTP)中调控一氧化氮变化的膜信号途径。方法:采用胞外记录方法检测LTP产生和维持。用生化反应方法检测一氧化氮含量和一氧化氮合酶(nitricoxidesynthase,NOS)活性变化。结果:LTP产生后,NOS活性为(2.11±0.21)nkat/g,一氧化氮含量为(10.24±3.1)nmol/g。NMDA受体抑制剂AP-5在抑制LTP产生的同时,也显著阻滞一氧化氮含量和NOS活性升高。同样,L型钙通道阻断剂Diltiazem(30μmol/L)作用下,NOS活性降为(0.41±0.10)nkat/g一氧化氮含量降为(2.0±0.8)nmol/g;神经细胞黏附分子抗体存在条件下,NOS活性降为(0.43±0.09)nkat/g,一氧化氮含量降为(2.0±1.2)nmol/g。结论:膜上NMDA受体、L型钙通道和神经细胞黏附分子共同参与了对LTP中一氧化氮活动的调控。     

降钙素基因相关肽对高血压病患者血管平滑肌细胞一氧化氮合酶的影响

目的探讨降钙素基因相关肽(CGRP)对高血压病(EH)患者动脉血管平滑肌细胞(VSMC)的一氧化氮合酶(NOS)、一氧化氮(NO)产生和细胞增殖的作用.方法对高血压病患者和血压正常者(NT)的动脉VSMC进行培养,分别测定两组VSMC的NO含量、NOS活性、细胞数量和细胞周期,观察高血压病患者VSMC的NO产生和细胞增殖以及CGRP对其的影响.结果①高血压病患者VSMC的NO含量和NOS活性分别为(42.73±6.76)μmol/2.5×106 cells和(0.24±0.05)nmol/min,均显著低于血压正常对照组的(74.52±4.37)μmol/2.5×106 cells和(0.55±0.10)nmol/min,P均＜0.01;细胞数量、细胞周期中的S期百分率和增殖指数(PI)分别为(10.39±1.30)×106个/ml,(35.78±1.0)%和(54.84±1.98)%,均显著高于血压正常对照组的(7.67±0.98)×106个/ml,(28.88±1.07)%和(44.12±1.43)%(P均＜0.01).②在CGRP干预下,高血压病患者VSMC的NO含量和NOS活性均较血压正常对照组为低(P＜0.01);细胞数量、细胞周期中的S期百分率和PI均较血压正常对照组为高(P均＜0.01).③在CGRP干预下,两组VSMC的NO含量和NOS活性均较基础状态显著增加和增强(P＜0.01);两组VSMC的细胞数量、细胞周期中的S期百分率和PI均较基础状态显著减低(P＜0.01).结论高血压病患者VSMC的NOS-NO系统可能存在功能或结构的异常,并对CGRP的反应性降低,这可能是高血压的发病原因之一.     

游泳对慢性低氧高二氧化碳大鼠一氧化氮代谢的影响

背景：运动锻炼能提高正常机体和心血管疾病患者血管一氧化氮的生成能力，但运动锻炼对慢性低氧时一氧化氮代谢有积极的影响。目的：探讨游泳锻炼对慢性低氧高二氧化碳大鼠一氧化氮代谢及肺动脉平均压(mean pulmonary artery pressuse，mPAP)的影响。设计：随机对照的实验研究。地点、材料和干预：实验在温州医学院肺心病研究室完成。实验选用31只SD大鼠随机分成正常对照组(10只)与模型组(21只)。模型组低氧4周后，又随机分为模型对照组(8只)与游泳锻炼组(13只)。采用比色法测定血浆、肺组织、右心室组织一氧化氮代谢产物(NO^2-／NO^3-)的含量，液体闪烁仪测定[^3H]瓜氨酸的生成量，计算肺组织、右心室组织组织型NOS(tissue NOS，tNOS)、诱导型NOS(induced NOS，iNOS)和原生型NOS(constitutive NOS，cNOS)的活性。主要观察指标：游泳对慢性低氧高二氧化碳在大鼠mPAP、右心室质量，血浆、肺组织、右心室组织NO2-／NO3-含量、NOS活性的影响。结果：游泳锻炼组的血浆、肺与右心室组织的NO2-／NO3-的含量和cNOS的活性明显高于模型对照组；同时，游泳锻炼组的mPAP[(19．62&;#177;1.32)mm Hg]显著低于模型对照组[(15．19&;#177;1．11)mm Hg](q=12、632，P&;lt;0、01)。结论：游泳锻炼有促使一氧化氮生成增加和降低肺动脉压的作用。     

Europium oxide nanorod-reduced graphene oxide nanocomposites towards supercapacitors

Fast charge/discharge cycles are necessary for supercapacitors applied in vehicles including, buses, cars and elevators. Nanocomposites of graphene oxide with lanthanide oxides show better supercapacitive performance in comparison to any of them alone. Herein, Eu₂O₃ nanorods (EuNRs) were prepared through the hydrothermal method and anchored onto the surface of reduced graphene oxide (RGO) by utilizing a sonochemical procedure (in an ultrasonic bath) through a self-assembly methodology. The morphologies of EuNRs and EuNR-RGO were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD) and IR spectroscopy. Then, we used EuNRs and EuNR-RGO as electrode materials to investigate their supercapacitive behavior using cyclic voltammetry, galvanostatic charge–discharge, and electrochemical impedance spectroscopy techniques. In a 3.0 M KCl electrolyte and with a scan rate of 2 mV s⁻¹, EuNR-RGO exhibited a specific capacity of 403 F g⁻¹. Galvanostatic charge–discharge experiments demonstrated a specific capacity of 345.9 F g⁻¹ at a current density of 2 A g⁻¹. The synergy between RGO''s flexibility and EuNR''s high charge mobility caused these noticeable properties.

Fast charge/discharge cycles are necessary for supercapacitors applied in vehicles including, buses, cars and elevators.     

Metal oxide heterojunctions using a printable nickel oxide ink

Wide band gap metal oxides are ideally suited for inorganic optoelectronic devices. While zinc oxide is a commonly used n-type material, there is still a lot of ongoing work for finding suitable p-type oxides. In this work, we describe a two-step route to formulate a stable and conducting p-type nickel oxide (NiO) nanofluid. NiO nanoparticles were synthesised using a bottom-up wet chemical approach and dispersed in ethylene glycol to form a nanofluid. The viscosity and surface tension of the nanofluid were optimised for printing. The printing was done using an extrusion-based direct writer. The NiO nanofluid was printed onto an aluminum-doped zinc oxide layer and annealed at different temperatures. Electrical characterisation of the junction was used to extract the junction barrier for carriers across the interface. The resulting heterojunction was found to exhibit rectifying behaviour, with the highest rectification ratio occurring at an annealing temperature of 250 °C. This annealing temperature also resulted in the lowest junction barrier height, and was in excellent agreement with theoretically predicted values. The development of a printed p-type ink will help in the realisation of oxide-based printed electronic devices.

We present a printed p-NiO/n-AZO heterojunction exhibiting high rectification ratios using a NiO ink synthesized by a chemical route.     

Modulation of nitric oxide synthase by nitric oxide donor compounds in migraine

A controlled study was performed to assess the involvement of the nitric oxide pathway in migraine pathophysiology. Thirteen patients with migraine without aura and seven clinically healthy subjects (C) were selected. All of the migraine patients were studied both before, during an asymptomatic phase (t ₀), and 1 h after the administration of 5 mg isosorbide dinitrate, a nitric oxide donor able to induce an experimental migraine attack (t ₁). The nitric oxide levels were analyzed as nitrite accumulation in serum samples, in peripheral blood mononuclear cell extracts, and culture supernatants. Basal nitrite levels in serum samples and peripheral blood mononuclear cell culture supernatants of migraine patients and healthy subjects indicated that migraine patients possess an activated nitric oxide synthesis pathway (t ₀ vs. C F=8.16,P<0.01 and F=16.2,P<0.01, respectively). As expected, in the migraine patients treated with the nitric oxide donor, a marked increase of nitrite levels was observed in sera (t ₁ vs.t ₀ P<0.05,t=3.05). In contrast, during the nitric oxide donor-induced migraine attacks a statistically significant decrease of nitrite levels in peripheral blood mononuclear cell culture supernatants was observed (t ₁ vs.t ₀ P<0.01,t=−4.03), whereas a significant increase of nitrite in total cell extracts was detected (t ₁ vs.t ₀ P<0.001,t=−6.89). These preliminary data suggest that nitric oxide could be involved in the neurovascular modifications leading to a migraine attack.     

Exhaled nitric oxide

We introduce the standard method of measurement of nitric oxide recommended by American thoracic society in 1999 and report the results of exhaled NO and nasal NO in patients with obstructive sleep apnea syndrome(OSAS). Our data showed lower exhaled NO output in the patients with OSAS than that of normal volunteers(NV) and that of patients with simple obesity(SO). On the other hand, nasal NO in the OSAS patients is higher than that of NV and that of SO patients. Also, there were significant relationships between apnea index and exhaled NO and between desaturation during sleep and nasal NO. These findings suggested that NO from lower and upper airway will be a non-invasive maker of sleep disordered breathing in future.     

Nitrous oxide analgesia

Great strides have been made in the prehospital and Emergency Department management of patients, yet the relief of pain and suffering is something that is often forgotten or, if not overlooked, provided in a suboptimal fashion. It is too easy not to feel the pain the patient has or that is is produced while one is seeking to help. The optimal analgesic should have rapid onset, short duration, few side effects, and no major adverse reactions. Nitrous oxide, known since 1776, is perhaps the drug that comes closest to meeting that ideal.