TRPC1对慢性阻塞性肺疾病慢性气道炎症的影响

目的探讨瞬时感受器电位通道C1(TRPC1)在慢性阻塞性肺疾病(慢阻肺)患者支气管黏膜上皮的表达水平及其与慢性气道炎症之间的关系。方法选取因不明原因肺部结节行纤维支气管镜检查的78例患者,依据慢性阻塞性肺疾病诊治指南分为慢阻肺组(46例)及对照组(32例),其中慢阻肺组再随机分为两个亚组:每日3次规律使用吸入型激素(ICS)布地奈德(ICS组,23例)及安慰剂(非ICS组,23例)治疗。所有受检查者均行支气管肺泡灌洗及支气管镜下刷检。Western Blot及qRT-PCR法检测刷检支气管上皮细胞内TRPC1表达水平,支气管肺泡灌洗液(BALF)行细胞学分类计数。酶联免疫吸附法检测BALF上清液中炎症介质白细胞介素13(IL-13)、成纤维生长因子2(FGF-2)表达水平。结果慢阻肺组支气管上皮细胞内的TRPC1 mRNA、蛋白表达水平明显高于对照组(P<0.05);ICS组的TRPC1表达水平低于非ICS组(P<0.05)。与对照组相比,慢阻肺组BALF中的中性粒细胞、巨噬细胞、淋巴细胞计数及IL-13、FGF-2水平均明显升高(P<0.05)。而ICS组BALF中的中性粒细胞、巨噬细胞、嗜酸性粒细胞、淋巴细胞计数及IL-13、FGF-2表达水平则低于非ICS组(P<0.05)。相关性分析结果显示,TRPC1 mRNA和蛋白表达水平与肺功能第一秒用力呼吸容积(FEV 1)占预计值百分比(FEV 1/Pre%)呈负相关(P<0.01),而与BALF中的中性粒细胞、巨噬细胞、淋巴细胞计数及IL-13、FGF-2水平呈正相关(P<0.05)。结论TRPC1可能通过参与慢阻肺慢性气道炎症过程促进疾病的发生发展,而ICS在一定程度上可干预该作用。     

感觉门控P50在特发性BPPV成功复位后残余头晕中的应用

目的 探讨特发性良性阵发性位置性眩晕（benign paroxysmal positional vertigo,BPPV）成功复位后出现残余头晕的患者感觉门控P50特点。方法 选择2018年6月至2019年11月就诊于大连市第三人民医院符合入组条件的确诊为BPPV并成功行手法复位后的患者60例,根据治疗7天后有无残余头晕（residual dizziness,RD）分为RD组和无RD组,行感觉门控电位P50检测,记录S1-P50及S2-P50的潜伏期、波幅及S2-P50/S1-P50波幅比值,进行统计学分析。结果 与无RD组相比,RD组S1-P50波幅减低,潜伏期延长,S2-P50波幅增高,潜伏期延长（P<0.05）;RD组S2/S1比值高于无RD组,差异具有统计学意义（P<0.05）。结论 感觉门控P50可以客观评价BPPV成功复位后残余头晕患者感觉门控功能缺损情况,提示患者可能存在情绪障碍,为临床治疗提供方向。     

Physiologically Based Pharmacokinetic Modeling in Regulatory Science: An Update From the U.S. Food and Drug Administration’s Office of Clinical Pharmacology

This commentary provides an update on the status of physiologically based pharmacokinetic modeling and simulation at the U.S. Food and Drug Administration's Office of Clinical Pharmacology. Limitations and knowledge gaps in integration of physiologically based pharmacokinetic approach to inform regulatory decision making, as well as the importance of scientific engagement with drug developers who intend to use this approach, are highlighted.     

Codelivery of Adriamycin and P-gp Inhibitor Quercetin Using PEGylated Liposomes to Overcome Cancer Drug Resistance

Transmembrane protein P-gp's overexpression at the drug-resistant cell membrane is the most important characteristic of multidrug resistance (MDR). Quercetin (QUE) can effectively suppress the function of P-gp to reverse MDR. This study uses QUE as the P-gp inhibitor andfilm-ultrasound technique with ammonium sulfate transmembrane gradient method to prepare long-circulating liposomes simultaneously encapsulating QUE and Adriamycin (doxorubicin) (AMD/DOX). The optimal conditions for the preparation of AMD_QUE_long-circulating liposomes (SLs) are as follows: hydrogenated soybean phospholipids (HSPC):cholesterol:DSPE-PEG 2000 = 73.07:24.36:2.57 mol/mol, QUE:HSPC = 1:20 mol/mol, AMD:HSPC = 1:7.9 w/w (NH₄₎₂SO₄ 0.15 mol/L, drug loaded (AMD) at 55°C for 25 min). The average encapsulation efficiency of AMD and QUE was 97.49% and 95.50%, respectively. The average particle size is 85 nm (n = 3), and the average zeta potential is ?14.9 mV. First, the pharmacokinetic study proved that codelivery liposomes enveloping QUE and AMD (AMD_QUE_SL) can obviously increase the blood concentration of AMD (C_max: 140.50 ± 32.37 μg/mL) and extend the half-life period of AMD in plasma (t_1/2:14.02 ± 1.54 h). Second, AMD_QUE_SL can obviously enhance the cell toxicity to AMD-resistant cell strains (HL-6/ADR and MCF-7/ADR), and the reverse effects on the resistance of HL-6/ADR and MCF-7/ADR is increased to 4.81-fold and 3.21-fold, respectively. Third, according to the in vivo pharmacodynamic study, the relative tumor volume and relative tumor growth of the AMD_QUE_SL group were the lowest. The inhibition rate of tumor growth of this group was the highest. It can be concluded that AMD_QUE_SL can effectively reverse MDR, lower cardiac toxicity of AMD in clinical treatment, and improve the clinical treatment effect of AMD.     

In Vitro and In Vivo Correlation of Hepatic Fraction of Metabolism by P450 in Dogs

1-Aminobenzotriazole (ABT) has been widely used as a nonspecific mechanism-based inhibitor of cytochrome P450 (P450) enzymes. It is extensively used in preclinical studies to determine the relative contribution of oxidative metabolism mediated by P450 in vitro and in vivo. The aim of present study was to understand the translation of fraction metabolized by P450 in dog hepatocytes to in vivo using ABT, for canagliflozin, known to be cleared by P450-mediated oxidation and UDP-glucuronosyltransferases–mediated glucuronidation, and 3 drug discovery project compounds mainly cleared by hepatic metabolism. In a dog hepatocyte, intrinsic clearance assay with and without preincubation of ABT, 3 Lilly compounds exhibited a wide range of fraction metabolized by P450. Subsequent metabolite profiling in dog hepatocytes demonstrated a combination of metabolism by P450 and UDP-glucuronosyltransferases. In vivo, dogs were pretreated with 50 mg/kg ABT or vehicle at 2 h before intravenous administration of canagliflozin and Lilly compounds. The areas under the concentration-time curve (AUC) were compared for the ABT-pretreated and vehicle-pretreated groups. The measured AUC_ABT/AUC_veh ratios were correlated to fraction of metabolism by P450 in dog hepatocytes, suggesting that in vitro ABT inhibition in hepatocytes is useful to rank order compounds for in vivo fraction of metabolism assessment.     

大黄素对胃癌细胞增殖、凋亡及ERK1/2-PKM2/P53通路的影响

摘 要 目的：探讨大黄素对胃癌细胞增殖、凋亡及ERK1/2-PKM2/P53通路的影响。 方法: 实验分为MGC803胃癌细胞组、氟尿嘧啶组、大黄素低剂量组、大黄素高剂量组,测定并比较各组细胞癌细胞活力、癌细胞单克隆形成数目、癌细胞凋亡率、穿膜孔数、以及MGC803胃癌细胞ERK1/2、PKM2、P53mRNA、蛋白水平。 结果: 与MGC803细胞组比较,氟尿嘧啶组、大黄素低、高剂量组吸光度（A）值、存活率水平、克隆形成数目、穿膜数、p ERK1/2、p PKM2 mRNA及蛋白表达水平降低,凋亡率、P53 mRNA及蛋白表达水平升高（P<0.05）。与氟尿嘧啶组比较,大黄素低剂量组A值、存活率水平、克隆形成数目、穿膜数、p ERK1/2、p PKM2 mRNA、蛋白升高,凋亡率、P53 mRNA、蛋白表达水平降低（P<0.05）。与大黄素低剂量组比较,大黄素高剂量组A值、存活率、细胞克隆形成数目、穿膜数、P ERK1/2及P PKM2 mRNA及蛋白表达水平明显降低,凋亡率、P53 mRNA及蛋白表达水平明显升高（P<0.05）。 结论: 大黄素可能通过抑制ERK1/2-PKM2通路诱导P53高表达从而抑制胃癌细胞的增殖及迁徙,促进胃癌细胞的凋亡。     

Nanoscale zerovalent iron particles induce differential cytotoxicity,genotoxicity, oxidative stress and hemolytic responses in human lymphocytes and erythrocytes in vitro

The growing usage of nanoscale zerovalent iron particles (nZVI) in the remediation of soil, ground/surface water has elicited large‐scale environmental release triggering human exposure. The size of nanomaterials is a key regulator of toxicity. However, the effect of a variable size of nZVI on genotoxicity is unexplored in human cells. To the best of our knowledge, in this study, the cytotoxic, genotoxic and hemolytic potential of nZVI‐1 (15 nm) and nZVI‐2 (50 nm) at concentrations of 5, 10 and 20 μg/mL was evaluated for the first time in human lymphocytes and erythrocytes treated for 3 hours. In erythrocytes, spherocytosis and echinocytosis occurred upon exposure to nZVI‐1 and nZVI‐2, respectively, leading to hemolysis. Lymphocytes treated with 20 μg/mL nZVI‐2 and 10 μg/mL nZVI‐1, incurred maximum DNA damage, although nZVI‐2 induced higher cyto‐genotoxicity than nZVI‐1. This can be attributed to higher Fe ion dissolution and time/concentration‐dependent colloidal destabilization (lower zeta potential) of nZVI‐2. Although nZVI‐1 showed higher uptake, its lower genotoxicity can be due to lesser Fe content, Fe ion dissolution and superior colloidal stability (higher zeta potential) compared with nZVI‐2. Substantial accumulation of Ca²⁺, superoxide anions, hydroxyl radicals and H₂O₂ leading to mitochondrial impairment and altered antioxidant enzyme activity was noted at the same concentrations. Pre‐treatment with N‐acetyl‐cysteine modulated these parameters indicating the indirect action of reactive oxygen species in nZVI‐induced DNA damage. The morphology of diffused nuclei implied the possible onset of apoptotic cell death. These results validate the synergistic role of size, ion dissolution, colloidal stability and reactive oxygen species on cyto‐genotoxicity of nZVI and unlock further prospects in its environmental nano‐safety evaluation.     

Shedding light on a potential hazard: Dental light-curing units

BackgroundDental light-curing units (LCUs) are powerful sources of blue light that can cause soft-tissue burns and ocular damage. Although most ophthalmic research on the hazards of blue light pertains to low levels from personal electronic devices, computer monitors, and light-emitting diode light sources, the amount of blue light emitted from dental LCUs is much greater and may pose a “blue light hazard.”MethodsThe authors explain the potential risks of using dental LCUs, identify the agencies that provide guidelines designed to protect all workers from excessive exposure to blue light, discuss the selection of appropriate eye protection, and provide clinical tips to ensure eye safety when using LCUs.ResultsWhile current literature and regulatory standards regarding the safety of blue light is primarily based on animal studies, sufficient evidence exists to suggest that appropriate precautions should be taken when using dental curing lights. The authors found it difficult to find on the U.S. Food and Drug Administration database which curing lights had been cleared for use in the United States or Europe and could find no database that listed which brands of eyewear designed to protect against the blue light has been cleared for use. The authors conclude that more research is needed on the cumulative exposure to blue light in humans. Manufacturers of curing lights, government and regulatory agencies, employers, and dental personnel should collaborate to determine ocular risks from blue light exist in the dental setting, and recommend appropriate eye protection. Guidance on selection and proper use of eye protection should be readily accessible.Conclusions and Practical ImplicationsThe Centers for Disease Control and Prevention Guidelines for Infection Control in the Dental Health-Care Setting–2003 and the Occupational Safety and Health Administration Bloodborne Pathogen Standard do not include safety recommendations or regulations that are directly related to blue light exposure. However, there are additional Occupational Safety and Health Administration regulations that require employers to protect their employees from potentially injurious light radiation. Unfortunately, it is not readily evident that these regulations apply to the excessive exposure to blue light. Consequently employers and dental personnel may be unaware that these Occupational Safety and Health Administration regulations exist.