维生素E对D-半乳糖亚急性中毒拟衰老模型鼠自由基及相关生化指标的影响

目的 研究维生素E(VE)对D-半乳糖(D-gal)亚急性中毒拟衰老模型鼠自由基产生及相关生化指标的影响.方法 昆明小鼠颈背部皮下注射D-ga140mg·kg<'-1>·d<'-1>制备D-gal亚急性中毒导致的衰老鼠模型.将模型鼠分为4组,除对照组外,其他3组模型鼠分别灌胃以60、30、15 mg·kg<'-1>·d<'-1>VE,10w后杀鼠.摘眼球取血,室温离心,分离血清,采用硫代巴比妥酸(TBA)法检测血清中丙二醛(MDA)含量,黄嘌呤氧化酶法检测血清中总超氧化物歧化酶(SOD)活性;采用ISP半自动生化分析仪检测血清中血糖(Glu)、总胆固醇(TC)、甘油三酯(TG)的含量.结果 模型鼠血清中MDA含量显著高于正常对照组(P<0.05),VE喂饲的3个实验组小鼠血清MDA含量显著低于对照组(P<0.05).模型鼠血清总SOD含量显著低于正常对照组(P<0.05),VE喂饲的3个实验组小鼠血清总SOD含量显著高于对照组(P<0.05).模型鼠血清中的Glu、TC、TG含量显著高于正常对照组(P<0.05).VE喂饲的3个实验组小鼠血清中Glu、TC、TG与对照组无显著差异.结论 VE可以对衰老鼠的氧自由基损伤发挥保护作用,为临床将VE作为一种抗衰老药物应用提供了进一步的试验依据.     

番茄红素对D-半乳糖致衰老小鼠的抗氧化作用

目的观察番茄红素对D-半乳糖所致衰老小鼠的抗氧化作用。方法用D-半乳糖复制亚急性衰老小鼠模型,实验分空白对照组、模型对照组、番茄红素组(20与40mg·kg-1.d-1)和维生素E组(100mg·kg-1.d-1),实验6w后处死动物,测定血清、肝脏及脑组织中的丙二醛(MDA)含量及超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-Px)活性。结果番茄红素可显著降低衰老小鼠血清、肝脏及脑组织中的MDA含量,提高SOD、GSH-Px活性。结论番茄红素有一定的抗衰老作用。     

何首乌饮对衰老大鼠抗氧化能力及血脂的影响

目的探讨何首乌饮的抗衰老机制。方法采用D-半乳糖连续腹腔注射致亚急性衰老大鼠模型,测定何首乌饮灌胃后大鼠血清中血脂和丙二醛（MDA）含量、总抗氧化能力（T-AOC）、谷胱甘肽过氧物酶（GSH-Px）活性、超氧化物歧化酶（SOD）活力。结果亚急性衰老模型组大鼠血清甘油三酯（TG）、总胆固醇（TC）、MDA含量明显升高,高密度脂蛋白胆固醇（HDL-C）、SOD、GSH-Px、T-AOC明显下降,与正常对照组大鼠比较差异显著（P〈0.05,P〈0.01）,经何首乌饮灌胃治疗后TG、TC、MDA含量下降,HDL-C、SOD、GSH-Px、T-AOC含量升高均接近正常水平,与模型组大鼠有显著差异（P〈0.01）。结论何首乌饮明显提高衰老大鼠体内的HDL-C、SOD、GSH-Px、T-AOC水平,降低TG、TC、MDA含量,何首乌饮具有抗衰老作用,其抗衰老作用可能与此有关。     

杜仲种粕对衰老模型小鼠抗氧化能力的影响

目的 研究杜仲种粕对衰老模型小鼠体内抗氧化能力的影响.方法 通过连续颈部皮下注射D-半乳糖(350mgkg-1d-1)建立小鼠亚急性衰老模型.同时用杜仲种粕(300 mg·kg-1·d-1)灌胃,6 w后检测各组血清、肝脏组织与脑组织中超氧化物歧化酶(SOD)活力、过氧化氢酶(CAT)活力、丙二醛(MDA)的含量. 结果 杜仲种粕可以提高血清、肝脏组织与脑组织中SOD、CAT活力,降低血清、肝脏组织与脑组织中的MDA含量,与衰老模型组相比差异显著(P＜0.05). 结论 杜仲种粕可以提高D-半乳糖致亚急性衰老小鼠的抗氧化能力.     

左卡尼汀在全肠外营养大鼠短肠综合征模型中的作用

目的探讨左卡尼汀在全肠外营养大鼠短肠综合征模型中的作用。方法健康雄性Wistar大鼠50只,随机分为5组,每组10只大鼠,第1组为假手术组,其余4组分别为生理盐水对照组、左卡尼汀低剂量组(50 mg·kg-1·d-1)、中剂量组(100 mg·kg-1·d-1)、高剂量组(200 mg·kg-1·d-1);5组均予全肠外营养液支持治疗。采用黄嘌呤氧化法和硫代巴比妥酸显色法分别测定大鼠血清丙二醛(MDA)浓度和超氧化物歧化酶(SOD)活力,并按试剂盒说明书操作测钠钾ATP酶活力,并检测肝功能及脂质代谢水平。结果左卡尼汀组大鼠MDA含量明显低于对照组;左卡尼汀给药浓度与MDA下降水平现剂量依赖性。左卡尼汀组大鼠SOD活性显著高于对照组,大鼠SOD活性与左卡尼汀亦呈浓度依赖性,随左卡尼汀给药浓度增加SOD活性逐渐增加。左卡尼汀组大鼠ATP酶活力较对照组显著提高,并呈现左卡尼汀剂量依赖性。与生理盐水对照组相比,不同浓度左卡尼汀组大鼠肝组织甘油三酯(TG)和总胆固醇(TC)含量显著下降,而血清谷丙转氨酶(ALT)和谷草转氨酶(AST)活性显著升高。结论左卡尼汀可能有助于减少短肠综合征模型大鼠全肠外营养治疗后心力衰竭、肝功能损伤等情况的发生。     

褪黑素对非酒精性脂肪性肝炎大鼠肝脏CYP2E1表达的影响

目的 观察褪黑素(melatonin,MT)对非酒精性脂肪性肝炎大鼠肝脏CYP2E1表达的影响.方法 雄性Wistar大鼠50只,随机分成5组,每组10只,正常对照组予普通饲料,模型组、MT低剂量组、MT中剂量组、MT高剂量组予高脂饮食12周,各MT干预组依次给予MT(含≤1%无水乙醇)2.5 mg·kg-1·d-1、5.0 mg·kg-1·d-1、10 mg·kg-1·d-1腹腔注射,正常对照组、模型组予等量生理盐水(含1%无水乙醇)腹腔注射,12周末进行肝脏病理学检查.生化法测定肝匀浆三酰甘油(TG)、总胆同醇(TC)、超氧化物歧化酶(SOD)、丙二醛(MDA)、谷胱苷肽过氧化物酶(GSH-Px)值,免疫组化法检测肝脏CYP2EI的表达.结果 与正常对照组比较,模型组大鼠肝细胞呈中-重度脂肪变性,肝匀浆TG、TC、MDA值明显升高(P＜0.01);肝匀浆SOD、GSH-Px明显降低,CYP2F1表达强度增加.与模型组比较,各MT干预组肝脏病理变化逐渐改善,肝匀浆TC、TG、MDA值逐渐降低,肝匀浆SOD、GSH-Px活力则逐渐升高,MT高剂量组肝脏CYP2E1表达减弱(P＜0.05).结论 MT能显著抑制非酒精性脂肪性肝炎大鼠肝脏CYP2E1的表达,提高抗氧化酶活性,抑制脂质过氧化反应.     

江苏地产白首乌C21甾苷抗衰老作用研究

目的研究江苏地产白首乌C21甾苷(C21 steroidal glycoside,CSG)抗氧化、耐缺氧、抗疲劳等抗衰老作用。方法以维生素E[VE,100mg/(kg.d)]为对照,观察CSG低、中、高剂量组[10mg/(kg.d)、20mg/(kg.d)、40mg/(kg.d),即CL、CM、CH组]对小鼠常压耐缺氧试验,负重游泳试验和D-半乳糖(D-gal)亚急性衰老模型小鼠的影响。测定小鼠常压耐缺氧和负重游泳时间,取血清、心、肝、脑组织,黄嘌呤氧化酶法测定超氧化物歧化酶(SOD)活性,硫代巴比妥酸法测定丙二醛(MDA)含量,ELISA法检测端粒酶活性。结果与正常对照组相比,CSG和VE能够延长健康小鼠常压耐缺氧和负重游泳时间,提高D-gal模型小鼠血清、心、肝、脑SOD活性,降低MDA含量;中、高剂量CSG组小鼠血清端粒酶活性升高;CSG低、中、高剂量组及VE组小鼠心脏端粒酶活性均升高(P<0.01);CSG及VE对小鼠肝及脑组织端粒酶活性无影响。结论CSG能拮抗自由基损伤,提高健康小鼠常压耐缺氧和负重游泳时间,提高D-gal衰老模型小鼠血清、心、肝、脑组织SOD活性,减少MDA含量,提高心脏组织中端粒酶活性。具有抗氧化、延缓衰老、抗疲劳作用。     

瓜蒌皮提取液对大鼠缺血心肌的保护作用

目的探讨瓜蒌皮提取液对大鼠缺血性心肌损伤的拮抗作用及相关机制。方法选用健康Wistar大鼠40只,随机分为正常对照组、心肌缺血(MI)组、单硝酸异山梨酯片(IMT)组、瓜蒌皮提取液(PTE)组。正常对照组和MI组用生理盐水(0.1 ml·kg-1·d-1)连续灌胃15 d,而IMT组及PTE组分别以0.125 mg·kg-1·d-1的IMT及3.0 g·kg-1·d-1的PTE连续灌胃15 d。从第13天起,正常对照组皮下注射生理盐水,MI组、IMT组和PTE组皮下注射异丙肾上腺素复制MI模型,连续注射3 d,以标准Ⅱ导心电图改变作为判定标准。末次注入盐酸异丙肾小腺素(Iso)后检测血清心肌酶、超氧化物歧化酶(SOD)、丙二醛(MDA)和内源性一氧化氮合酶(i NOS)含量变化及Bcl-2、Bax、内皮素(ET)在心肌表达情况。结果与正常对照组相比,MI组血清肌酸磷酶激酶(CK)、乳酶脱氢酶(LDH)、天门冬氨酸氨基转移酶(AST)、i NOS活性增强,MDA含量增加而SOD活性下降,并且在心肌组织中Bcl-2、Bax、ET表达均增加(P<0.05)。IMT组与PTE组差异无显著性。与MI组,PTE可显著抑制血清CK、LDH、AST、i NOS活性,使MDA水平降低、但SOD活性提高(P<0.05或P<0.01);同时,PTE可增加心肌组织内Bcl-2蛋白表达,降低Bax、ET表达,与MI组比较均有显著性差异(P<0.05或P<0.01)。结论 PTE对缺血心肌具有保护作用,其机制与抗氧化应激、稳定心肌细胞膜、抑制冠脉血管收缩、抗细胞凋亡有关。     

衰老因素对动脉粥样硬化大鼠血脂等指标的影响

目的观察亚急性衰老联合动脉粥样硬化模型在血脂等方面与动脉粥样硬化模型的区别。方法 2月龄健康雄性SD大鼠随机分为正常组、AS组、AS+衰老组和衰老组。14 w后处死、取材,测定血清甘油三酯(TG)、总胆固醇(TC)、低密度脂蛋白胆固醇(LDL-C)、高密度脂蛋白胆固醇(HDL-C)、氧化型低密度脂蛋白(oxLDL)、丙二醛(MDA)、超氧化物歧化酶(SOD)含量,根据公式计算动脉硬化指数(AI)值,并进行比较。结果与正常组相比,其余各组TC、TG、LDL、oxLDL、AI水平升高(P<0.05),AS+衰老组HDL含量降低(P<0.05),各组SOD水平降低(P<0.05)。与AS组比较,AS+衰老组TC、LDL、oxLDL、AI水平升高(P<0.05),HDL-C、SOD含量降低(P<0.05)。结论在AS模型基础上加入D-半乳糖干预造成一定程度的老化可加剧AS模型大鼠TG、TC、LDL、HDL、oxLDL、MDA、SOD指标的变化。     

中等负荷跑台训练对衰老模型大鼠心肌相关生化指标的影响

目的观察中等负荷跑台训练对D-半乳糖致衰老大鼠心肌的影响。方法将离乳两月龄雄性SD大鼠40只随机分为正常对照组9只、衰老模型对照组9只,衰老模型训练(Ⅰ组)11只和衰老模型训练(Ⅱ组)11只,6 w后,检测心肌丙二醛(MDA)含量,超氧化物歧化酶(SOD)活性。结果四组大鼠心肌SOD活性及MDA含量组间比较均有显著差异(P<0.05),而衰老模型训练Ⅰ组心肌相关指标要优于衰老模型训练Ⅱ组大鼠。结论中等负荷的运动训练能延缓心脏衰老,清除心脏部分氧自由基,增强SOD的活性,隔天训练要比每天训练更能提高心肌SOD活性、降低心肌MDA含量。     

Advances in Retinal Tissue Engineering

Retinal degenerations cause permanent visual loss and affect millions world-wide. Current treatment strategies, such as gene therapy and anti-angiogenic drugs, merely delay disease progression. Research is underway which aims to regenerate the diseased retina by transplanting a variety of cell types, including embryonic stem cells, fetal cells, progenitor cells and induced pluripotent stem cells. Initial retinal transplantation studies injected stem and progenitor cells into the vitreous or subretinal space with the hope that these donor cells would migrate to the site of retinal degeneration, integrate within the host retina and restore functional vision. Despite promising outcomes, these studies showed that the bolus injection technique gave rise to poorly localized tissue grafts. Subsequently, retinal tissue engineers have drawn upon the success of bone, cartilage and vasculature tissue engineering by employing a polymeric tissue engineering approach. This review will describe the evolution of retinal tissue engineering to date, with particular emphasis on the types of polymers that have routinely been used in recent investigations. Further, this review will show that the field of retinal tissue engineering will require new types of materials and fabrication techniques that optimize the survival, differentiation and delivery of retinal transplant cells.     

International Hemoglobin Information Center Policies - Ihic

Abstract

The levels of the inactive hemoglobin (Hb) pigments [such as methemoglobin (metHb), carboxyhemoglobin (HbCO) and sulfohemoglobin (SHb)] and the active Hb [in the oxyhemoglobin (oxyHb) form] as well as the blood Hb concentration in healthy non pregnant female volunteers were determined using a newly developed multi-component spectrophotometric method. The results of this method revealed values of SHb% in the range (0.0727–0.370%), metHb% (0.43–1.0%), HbCO% (0.4–1.52%) and oxyHb% (97.06–98.62%). Furthermore, the results of this method revealed values of blood Hb concentration in the range (12.608–15.777?g/dL). The method is highly sensitive, accurate and reproducible.     

同型半胱氨酸对血管内皮细胞合成蛋白聚糖的影响

为探讨同型半胱氨酸对血管内皮细胞合成蛋白聚糖的影响，采用400umol／L同型半胱氨酸作用于培养的人脐静脉内皮细胞，以^35S-Na2SO4为示踪物标记细胞合成的蛋白聚糖，通过离子交换层析，凝胶过滤层析分离蛋白聚糖。结果发现，实验组培养液中总蛋白聚糖降低，硫酸乙酰肝素蛋白聚糖及硫酸软骨素-硫酸皮肤素蛋白聚糖含量也降低，但其百分含量未见改变。细胞层中蛋白聚糖未见明显变化。     

Methemoglobin Forming Effect of Dimethyl Trisulfide in Mice

Abstract

Dimethyl trisulfide (DMTS) is a natural organic trisulfide that has been patented as a promising antidotal candidate against cyanide (CN). The primary mode of action of DMTS is as a sulfur donor that enables the conversion of CN to thiocyanate. Recently, it was discovered that DMTS is capable of oxidizing hemoglobin (Hb) to methemoglobin (MetHb) in vitro. The goal of these experiments was to measure the extent of DMTS-induced MetHb formation in vivo. In these experiments, intramuscular (IM) injections of formulated DMTS were administered to mice. Following the IM injection, blood was drawn and analyzed for MetHb using a rapid spectrophotometric method. Methemoglobin levels peaked in a dose-dependent manner between 20 and 30?min., and then began dropping. The highest MetHb levels measured for the 50, 100, 200 and 250?mg/kg doses of DMTS were respectively 3.28, 6.12, 9.69, and 10.76% MetHb. These experiments provide the first experimental evidence that IM administered DMTS generates MetHb in vivo and provide additional evidence for the presence of a secondary therapeutic pathway for DMTS - CN scavenging by DMTS-generated MetHb.     

Efficacy of combination treatment with cyclosporin A and corticosteroids for acute interstitial pneumonitis associated with dermatomyositis

Interstitial pneumonitis (IP) associated with polymyositis and dermatomyositis (PM/DM) is a serious complication that affects prognosis. We therefore undertook a retrospective multicenter study to examine the efficacy of a combination treatment with cyclosporin A (CsA) and corticosteroids. Fifty-three IP patients with PM/DM (9 PM, 44 DM) were analyzed. Thirty-two patients treated with CsA plus corticosteroids (9 PM, 23 DM) were included in the study. Four parameters, i.e., subjective symptoms, ausculatory sound, chest radiographs, and respiratory index, were serially evaluated. A general evaluation was performed 4 weeks after the start of the combination treatment. All patients with PM and chronic IP with DM, and 52% of those with acute IP with DM were graded as better than partially effective in the general evaluation. In contrast, all patients graded as progressive in the general evaluation had acute IP with DM. It is of note that in acute IP with DM, the survival rate of the group primarily treated with CsA and corticosteroids from the early stage of their disease was significantly higher than that of the group initially treated with corticosteroids alone (P = 0.049). In conclusion, a combination treatment of CsA and corticosteroids from the early stage of disease may be advantageous for patients with IP with PM/DM, especially acute IP with DM.     

Efficacy of combination treatment with cyclosporin A and corticosteroids for acute interstitial pneumonitis associated with dermatomyositis

Abstract

Interstitial pneumonitis (IP) associated with polymyositis and dermatomyositis (PM/DM) is a serious complication that affects prognosis. We therefore undertook a retrospective multicenter study to examine the efficacy of a combination treatment with cyclosporin A (CsA) and corticosteroids. Fifty-three IP patients with PM/DM (9 PM, 44 DM) were analyzed. Thirty-two patients treated with CsA plus corticosteroids (9 PM, 23 DM) were included in the study. Four parameters, i.e., subjective symptoms, ausculatory sound, chest radiographs, and respiratory index, were serially evaluated. A general evaluation was performed 4 weeks after the start of the combination treatment. All patients with PM and chronic IP with DM, and 52% of those with acute IP with DM were graded as better than “partially effective” in the general evaluation. In contrast, all patients graded as “progressive” in the general evaluation had acute IP with DM. It is of note that in acute IP with DM, the survival rate of the group primarily treated with CsA and corticosteroids from the early stage of their disease was significantly higher than that of the group initially treated with corticosteroids alone (P = 0.049). In conclusion, a combination treatment of CsA and corticosteroids from the early stage of disease may be advantageous for patients with IP with PM/DM, especially acute IP with DM.     

Papillomavirus Infectious Pathways: A Comparison of Systems

The HPV viral lifecycle is tightly linked to the host cell differentiation, causing difficulty in growing virions in culture. A system that bypasses the need for differentiating epithelium has allowed for generation of recombinant particles, such as virus-like particles (VLPs), pseudovirions (PsV), and quasivirions (QV). Much of the research looking at the HPV life cycle, infectivity, and structure has been generated utilizing recombinant particles. While recombinant particles have proven to be invaluable, allowing for a rapid progression of the HPV field, there are some significant differences between recombinant particles and native virions and very few comparative studies using native virions to confirm results are done. This review serves to address the conflicting data in the HPV field regarding native virions and recombinant particles.     

Golimumab for moderate to severe ulcerative colitis

Introduction: Golimumab (GLM) is a subcutaneously administered human anti-tumor necrosis factor (TNF) agent that has been approved by the regulatory authorities for the treatment of moderate to severe ulcerative colitis (UC) in 2013.

Areas covered: Maintained clinical remission rates up to 50% have been shown in UC patients receiving GLM, and higher GLM serum concentrations have been associated with improved clinical outcomes. Approximately 50% of UC patients do not respond to induction therapy with GLM, and up to 40% of GLM responders will lose response over time. In most patients, loss of response is associated with low serum GLM concentrations, which suggests insufficient exposure to GLM. Low GLM serum concentrations may be avoided by therapeutic drug monitoring.

Expert commentary: So far, the therapeutic window for GLM has not yet been defined, but options to dose increase GLM based on therapeutic drug monitoring might result in improved clinical outcome and higher success rates.     

The Mitochondrial Permeability Transition: Role in Ischemia/Reperfusion Injury

The mitochondrial permeability transition (MPT) occurs when a non-specific pore opens in the inner mitochondrial membrane and converts the mitochondrion from an organelle whose ATP production sustains the normal function of the cell to an instrument of death. Conditions favouring the MPT including high [Ca2+], oxidative stress and adenine nucleotide depletion, all of which occur when a tissue is reperfused following a period of ischemia. Cyclosporin A (CsA) and low pH (<7.0) are potent inhibitors of the MPT. Methods have been devised to demonstrate directly that the MPT pores open upon reperfusion but not during ischemia. The mechanism of the MPT appears to involve binding of mitochondrial cyclophilin (CyP) to the adenine nucleotide translocase (ANT) followed by a calcium-mediated conformational change that converts the ANT into a non-specific pore. Understanding the molecular mechanism has assisted in devising strategies that can be used to protect tissues from damage caused by reperfusion injury. These might also be of benefit in the prevention of multiple organ failure for which reperfusion injury of the gut is thought to be the initial trigger. Protective regimes include the pretreatment of tissues prior to ischemia/reperfusion with CsA (binds to CyP), free radical scavengers that reduce oxidative stress (e.g., pyruvate and propofol) and agents that decrease pHi (e.g., pyruvate or amelioride derivatives). Reperfusion injury can produce both immediate cell death by necrosis or delayed apoptotic cell death and it appears that the mitochondria determine which route is taken. Prolonged opening leads to rapid cell death by necrosis, whilst transient opening leads to cytochrome c release and subsequent apoptosis hours or days later.     

An Overview of Molecular Aspects of Iron Metabolism

Iron (Fe) is an essential, but potentially noxious, metal for almost all organisms. Its precise cellular regulation is necessary to ensure synthesis of numerous iron-containing proteins required for metabolic processes yet at the same time avoiding the build-up of potentially toxic levels of iron. In humans, iron-deficiency results in anemia, while excess iron can lead to organ damage as a result of a build-up of non-transferrin-bound iron (NTBI). In recent years, the cloning of novel proteins has clarified the mechanisms of iron uptake, storage and metabolic regulation. Our current knowledge of the molecular aspects of mammalian iron metabolism and NTBI are presented in this review.