无患子皂苷遗传毒性的研究

目的：评价无患子皂苷的急性毒性和遗传毒性,为无患子皂苷的日常应用提供毒理学依据。方法通过急性经口毒性试验、哺乳动物红细胞微核试验、细菌回复突变试验和体外哺乳动物细胞染色体畸变试验,检测无患子皂苷对原核生物和真核生物在基因水平和染色体水平的诱变性。结果无患子皂苷的雌雄小鼠急性经口毒性LD50均为4640 mg/kg,可见流涎和黏液便等中毒体征。小鼠骨髓细胞微核试验各剂量组与阴性对照组比较,差异均无统计学意义（ P〉0.05）;Ames试验在加或不加S9各剂量组及菌株条件下的回变菌落数均未超过自发回变菌落数（阴性对照）的2倍以上,未观察到剂量-效应关系;染色体畸变试验无患子皂苷对CHL的IC50为75μg/mL,各剂量组与阴性对照组比较,差异均无统计学意义（ P〉0.05）。在上述各试验中,阳性对照组与阴性对照组比较,差异均有统计学意义（ P〈0.01）。结论在本实验条件下,无患子皂苷不具有遗传毒性。     

白藜芦醇保护缺血再灌注大鼠心肌作用与miR-21的相关性

目的 观察白藜芦醇预处理后大鼠心肌微小RNA(miRNA)的表达变化,分析白藜芦醇介导的心肌保护作用与miR-21之间有否关系.方法 通过miRNA芯片微阵列方法和qRT-PCR检测并验证白藜芦醇灌胃预处理后的大鼠心肌miRNA表达谱；建立大鼠心肌缺血再灌注损伤模型,检测各组心肌梗死面积、心肌细胞凋亡率以及miR-21的表达水平.结果 白藜芦醇预处理后,大鼠心肌的miR-21表达水平约为对照组的2.5倍;miR-21阻逼剂对白藜芦醇预处理引起的miR-21高表达产生了明显的抑制作用；过表达的miR-21显著降低了心肌细胞凋亡率,心肌组织梗死面积明显缩小.结论 白藜芦醇可以调控心肌多种miRNA的表达水平,通过促进miR-21的表达,白藜芦醇能够抑制心肌细胞的凋亡,从而减轻缺血再灌注对心肌的损伤.     

Percutaneous ultrasound and endoscopic ultrasound-guided biopsy of solid pancreatic lesions: An analysis of 1074 lesions

Backgrounds: Percutaneous ultrasound (US) and endoscopic ultrasound (EUS)-guided pancreatic biopsies are widely accepted in the diagnosis of pancreatic diseases. Studies comparing the diagnostic performance of US- and EUS-guided pancreatic biopsies are lacking. This study aimed to evaluate and compare the diagnostic yields of US- and EUS-guided pancreatic biopsies and identify the risk factors for inconclusive biopsies. Methods: Of the 1074 solid pancreatic lesions diagnosed from January 2017 to February 2021 in our center, 275 underwent EUS-guided fine needle aspiration (EUS-FNA), and 799 underwent US-guided core needle biopsy (US-CNB/FNA). The outcomes were inconclusive pathological biopsy, diagnostic accuracy and the need for repeat biopsy. All of the included factors and diagnostic performances of both US-CNB/FNA and EUS-FNA were compared, and the independent predictors for the study outcomes were identified. Results: The diagnostic accuracy was 89.8% for EUS-FNA and 95.2% for US-CNB/FNA ( P = 0.001). Biopsy under EUS guidance [odds ratio (OR) = 1.808, 95% confidence interval (CI): 1.083-3.019; P = 0.024], lesion size < 2 cm (OR = 2.069, 95% CI: 1.145-3.737; P = 0.016), hypoechoic appearance (OR = 0.274, 95% CI: 0.097-0.775; P = 0.015) and non-pancreatic ductal adenocarcinoma carcinoma (PDAC) diagnosis (OR = 2.637, 95% CI: 1.563-4.449; P < 0.001) were identified as factors associated with inconclusive pathological biopsy. Hypoechoic appearance (OR = 0.236, 95% CI: 0.064-0.869; P = 0.030), lesions in the uncinate process of the pancreas (OR = 3.506, 95% CI: 1.831-6.713; P < 0.001) and non-PDAC diagnosis (OR = 2.622, 95% CI: 1.278-5.377; P = 0.009) were independent predictors for repeat biopsy. Biopsy under EUS guidance (OR = 2.024, 95% CI: 1.195-3.429; P = 0.009), lesions in the uncinate process of the pancreas (OR = 1.776, 95% CI: 1.014-3.108; P = 0.044) and hypoechoic appearance (OR = 0.127, 95% CI: 0.047-0.347; P < 0.001) were associated with diagnostic accuracy. Conclusions: Both percutaneous US- and EUS-guided biopsies of solid pancreatic lesions are safe and effective; though the diagnostic accuracy of EUS-FNA is inferior to US-CNB/FNA. A tailored pancreatic biopsy should be considered a part of the management algorithm for the diagnosis of solid pancreatic disease.