葛根素减轻PM2.5对血管内皮细胞损伤的机制研究

探讨PM2.5对EA.hy926型人脐静脉内皮细胞损伤的影响及葛根素的保护作用及机制。采集大气PM2.5分别以0,20,200,400 mg·L~(-1)染毒EA.hy926细胞24 h,MTT法测细胞存活率,流式细胞术测细胞凋亡,Western blot法测p-ERK1/2,Bax,Bcl-2蛋白水平,ELISA法测肿瘤坏死因子-α(TNF-α)及白细胞介素-6(IL-6)含量,并测细胞丙二醛(MDA)含量、超氧化物歧化酶(SOD)及乳酸脱氢酶(LDH)活性;分别加入葛根素(10,50,100μmol·L~(-1))和ERK1/2通路特异性阻滞剂PD98059 20μmol·L~(-1)检测葛根素的干预作用及机制。检测发现与对照组比较,PM2.5染毒后呈剂量依赖性降低EA.hy926细胞存活率,上调p-ERK1/2蛋白水平及Bax/Bcl-2蛋白比率以促进细胞凋亡,诱导分泌TNF-α及IL-6含量增高,降低SOD活性,增加MDA含量及LDH活性(P0.05);葛根素呈剂量依赖性增加EA.hy926细胞的存活率,下调p-ERK1/2蛋白水平及Bax/Bcl-2蛋白比率以抑制细胞凋亡,降低TNF-α及IL-6含量,增加SOD活性,降低MDA含量及LDH活性(P0.05)。研究显示葛根素可能通过抑制ERK1/2通路减轻PM2.5对EA.hy926细胞的损伤。     

唾液外泌体与口腔疾病相关研究进展

唾液外泌体是指存在于唾液中的直径在30～150 nm的细胞外囊泡。随着近年来技术手段的发展,大量研究揭示唾液外泌体在多种口腔疾病的发生发展中发挥重要作用,如唾液外泌体CD9及CD81通过调控细胞粘附及运动促进肿瘤细胞转移、唾液外泌体miR-24-3p通过作用于PER1促进肿瘤细胞增殖、唾液外泌体程序性细胞死亡配体-1(programmed cell death-ligand 1,PD-L1)mRNA抑制炎症组织的破坏等,具有作为诊断口腔癌、牙周炎等口腔疾病的生物标志物的潜能。因此,唾液外泌体可作为口腔疾病潜在的预后和诊断标志物。唾液外泌体除与口腔疾病,如口腔癌、牙周炎、口腔扁平苔藓、干燥综合征等有关外,还同远处部位肿瘤如胰腺癌、肺癌等及系统性疾病如帕金森综合征、炎症性肠病等密切相关;深入研究唾液外泌体对口腔、全身系统性疾病的诊断与治疗作用,开发唾液外泌体作为疾病诊断的生物标志物的潜力具有重要意义。     

酸性成纤维细胞生长因子在宫颈癌中的表达及其信号传导途径

目的探讨酸性成纤维细胞生长因子(aFGF)在宫颈癌发生发展中的作用及其信号传导机制.方法应用逆转录-聚合酶链反应技术(RT-PCR)对36例宫颈癌组织aFGF 及其受体FGFR1的表达进行了分析;并以不同浓度的aFGF 和酪氨酸蛋白激酶(TPK)抑制剂genistein诱导宫颈癌细胞株HeLa细胞,[γ-32P]ATP掺入外源性底物的方法,液体闪烁测定蛋白激酶C(PKC)及细胞外信号调节激酶(ERK)的活性.结果 aFGF mRNA 和FGFR1 mRNA在宫颈癌组织中的半定量检测结果分别为(1.233±0.064)和(1.168±0.103),与正常宫颈组织相比,差异有显著性(P<0.05),且在Ⅲ～Ⅳ期宫颈癌中的表达水平明显高于Ⅰ～Ⅱ期(P<0.05);随着aFGF浓度的增加,HeLa细胞PKC及ERK 活性随之升高,与aFGF浓度呈剂量依赖效应;genistein抑制细胞内PKC及ERK 活性,与genistein 浓度亦呈剂量依赖效应.结论提示aFGF 与宫颈癌的发生、发展、浸润呈正相关,其受体具有TPK活性,TPK激活后可进一步激活PKC和ERK,进一步证明PKC及ERK确是TPK的下游信号分子.     

Astrocytes in the damaged brain: Molecular and cellular insights into their reactive response and healing potential

Long considered merely a trophic and mechanical support to neurons, astrocytes have progressively taken the center stage as their ability to react to acute and chronic neurodegenerative situations became increasingly clear. Reactive astrogliosis starts when trigger molecules produced at the injury site drive astrocytes to leave their quiescent state and become activated. Distinctive morphological and biochemical features characterize this process (cell hypertrophy, upregulation of intermediate filaments, and increased cell proliferation). Moreover, reactive astrocytes migrate towards the injured area to constitute the glial scar, and release factors mediating the tissue inflammatory response and remodeling after lesion. A novel view of astrogliosis derives from the finding that subsets of reactive astrocytes can recapitulate stem cell/progenitor features after damage, fostering the concept of astroglia as a promising target for reparative therapies. But which biochemical/signaling pathways modulate astrogliosis with respect to both the time after injury and the type of damage? Are reactive astrocytes overall beneficial or detrimental for neuroprotection and tissue regeneration? This debate has been animating this research field for several years now, and an integrated view on the results obtained and the possible future perspectives is needed. With this Commentary article we have attempted to answer the above-mentioned questions by reviewing the current knowledge on the molecular mechanisms controlling and sustaining the reaction of astroglia to injury and its stem cell-like properties. Moreover, the cellular/molecular mechanisms supporting the detrimental or beneficial features of astrogliosis have been scrutinized to gain insights on possible pharmacological approaches to enhance astrocyte neuroprotective activities.     

氯沙坦抑制糖基化终末产物刺激培养的人内皮细胞外基质基因的表达

目的 探讨氯沙坦防治糖尿病血管病变的作用机理。方法 用反转录-聚合酶链反应(RT-PCR)和Northern印迹杂交方法测定了0.1～10 μmol·L^-1浓度的氯沙坦对经体外制备的糖基化终末代谢产物（AGEs）处理培养的人脐静脉内皮细胞（HUVECs）转化生长因子（TGF）-β₁和纤连蛋白（FN）基因表达的影响。结果 由AGEs处理的HUVECs TGF-β₁和FN mRNA表达较正常对照组明显增高；与AGEs组相比，TGF-β₁和FN mRNA的表达在氯沙坦1.0 μmol·L^-1时分别降低了29%和23%，10 μmol·L^-1时降低了56%和62%。结论 氯沙坦通过抑制AGEs刺激的内皮细胞TGF-β₁和FN mRNA表达，从而抑制细胞外基质的生成，防止血管重构可能是其防治糖尿病血管并发病的机理之一。     

依达拉奉对脑缺血再灌注损伤后p-ERK1/2表达的影响

目的:研究依达拉奉对脑缺血再灌注细胞损伤的影响及p-ERK1/2在此过程的作用。方法:将180只雄性ICR小鼠随机分为假手术组、生理盐水治疗组和依达拉奉治疗组。各组于缺血再灌注后分为30min、3h、6h、24h、48h等5个亚组。采用线栓法建立小鼠局灶性脑缺血再灌注模型。治疗组于脑缺血开始及再灌注后12h分别腹腔注射依达拉奉3mg/kg或等量生理盐水,于24h后进行小鼠神经功能学评分;应用免疫组织化学及Westernblot检测p-ERK1/2蛋白表达水平的变化;利用原位缺口末端标记法(TUNEL法)研究神经细胞凋亡的变化。结果:与生理盐水治疗组相比,依达拉奉治疗组小鼠神经行为学评分明显减少(P<0.05);p-ERK1/2免疫阳性细胞及蛋白表达明显减少(P<0.05);凋亡细胞也减少(P<0.05)。结论:依达拉奉能通过抑制与氧化应激有密切关系的p-ERK1/2信号通路显著减轻脑缺血再灌注损伤后神经细胞损伤。     

气道局部治疗对气道黏液高分泌干预作用的对比研究

目的探讨常用局部治疗性药物对慢性气道黏液高分泌作用的机制和特点。方法用超声雾化吸入中性粒细胞弹性蛋白酶(NE)复制慢性支气管炎动物模型,分别吸入糖皮质激素布地奈德(budesonide)、胆碱M受体阻断剂异丙托溴铵以及两者配伍联用进行干预,用酶联免疫吸附试验(ELISA)及斑点印迹法分别检测大鼠支气管肺泡灌洗液(BALF)中黏蛋白(MUC)的含量和MUC5ACmRNA表达水平。结果NE能显著增加气道MUC和MUC5ACmRNA的表达(P<0.01);普米克令舒和异丙托溴铵均可降低MUC和MUC5ACmRNA的表达(P<0.05),两者联用可增强抑制黏蛋白的效应(P<0.01)。结论NE是慢性气道黏液高分泌发生的重要因素;布地奈德和异丙托溴铵可抑制MUC基因及转录水平的表达,且两者联用有协同效应。     

UMP与ESWL治疗肾结石合并糖尿病患者的效果及对NGAL、Hb水平的影响研究

目的 探究超微经皮肾镜碎石术(UMP)与体外冲击波碎石术(ESWL)治疗肾结石合并糖尿病患者的效果及对血清中性粒细胞明胶酶相关载脂蛋白(NGAL)和血红蛋白(Hb)水平的影响.方法 选取2017年1月至2019年1月经本院收治的108例肾结石合并糖尿病患者作为研究对象,采用简单随机化原则将其分为两组,每组各54例.对照...     

Gut-derived lipopolysaccharide promotes alcoholic hepatosteatosis and subsequent hepatocellular carcinoma by stimulating neutrophil extracellular traps through toll-like receptor 4

Background/AimsBinge drinking leads to many disorders, including alcoholic hepatosteatosis, which is characterized by intrahepatic neutrophil infiltration and increases the risk of hepatocellular carcinoma (HCC). Molecular mechanisms may involve the migration of bacterial metabolites from the gut to the liver and the activation of neutrophil extracellular traps (NETs).MethodsSerum samples from both binge drinking and alcohol-avoiding patients were analyzed. Mouse models of chronic plus binge alcohol-induced hepatosteatosis and HCC models were used.ResultsA marker of NETs formation, lipopolysaccharide (LPS), was significantly higher in alcoholic hepatosteatosis and HCC patients and mice than in controls. Intrahepatic inflammation markers and HCC-related cytokines were decreased in mice with reduced NET formation due to neutrophil elastase (NE) deletion, and liver-related symptoms of alcohol were also alleviated in NE knockout mice. Removal of intestinal bacteria with antibiotics led to decreases in markers of NETs formation and inflammatory cytokines upon chronic alcohol consumption, and development of alcoholic hepatosteatosis and HCC was also attenuated. These functions were restored upon supplementation with the bacterial product LPS. When mice lacking toll-like receptor 4 (TLR4) received chronic alcohol feeding, intrahepatic markers of NETs formation decreased, and hepatosteatosis and HCC were alleviated.ConclusionsFormation of NETs following LPS stimulation of TLR4 upon chronic alcohol use leads to increased alcoholic steatosis and subsequent HCC.     

Size-Dependent Persistent Luminescence of YAGG:Cr3+ Nanophosphors

In the current work, YAGG:Cr³⁺ nanophosphors were synthesized by the Pechini method and then annealed at different temperatures in the range 800–1300 °C. The structure and morphology of the samples were characterized by X-ray Powder Diffraction (XRPD). The lattice parameters and average crystalline sizes as site occupation by Al³⁺ and Ga³⁺ ions were calculated from the Rietveld refinement data. To investigate the effect of crystalline size of the materials on their optical properties: excitation and emission spectra were recorded and analyzed. Finally, the effect of crystalline size on the probability of carrier recombination leading to PersL was determined experimentally with thermoluminescence analyses. The T_max-T_stop method was applied to determine the trap type and particle size (calcination temperature) effect on their redistribution. A correlation between structural changes and trap redistribution was found. In particular, the extinction of high-temperature TL maximum with increasing annealing temperatures is observed, while low-temperature TL maximum increases and reaches a maximum when the lattice parameter reaches saturation.