亚低温对急性肺损伤大鼠肺泡表面活性蛋白A含量的影响

目的 探讨亚低温对内毒素脂多糖(LPS)诱导急性肺损伤(ALI)大鼠肺泡表面活性蛋白A(SP-A)含量的影响.方法 按随机数字表法将40只雄性Wistar大鼠分组.采用气管内滴入LPS制备ALI动物模型;对照组气管内只滴人生理盐水.模型组和对照组分别于术后1 h和8 h处死8只大鼠;亚低温组于滴入LPS 1 h后将体温降低并维持在32.5～33.0℃,8 h后处死8只大鼠.各组分别于术前及术后1 h、8 h测定动脉血气,并计算氧合指数(PaO2/FiO2);采用酶联免疫吸附法检测支气管肺泡灌洗液(BALF)中SP-A含量;光镜下观察肺组织形态结构的变化.结果 气管内滴入LPS 1 h后,大鼠PaO2/FiO2均达到ALI的诊断标准.与对照1 h组比较,模型1 h组BALF中SP-A含量(μg/L)明显降低(53.27±1.95比74.81±6.55,P＜0.01);模型8 h组和亚低温8 h组SP-A含量(4.35±2.76和51.36±2.33)均较对照8 h组(70.81±5.01)明显降低,但亚低温8 h组SP-A含量较模型8 h组明显增高(均P＜0.01).光镜下观察,对照1 h和8 h组肺泡结构基本正常;模型8 h组肺组织炎症反应最重;模型1 h组和亚低温8 h组肺组织炎症反应较模型8 h组有所减轻.结论 亚低温能延缓内毒素诱导的ALI大鼠早期肺泡内SP-A含量下降的程度,在一定程度上可减轻肺损伤.

Abstract：

Objective To investigate the effect of hypothermia (HT) on the concentration of surfactant protein A (SP-A) during lipopolysaccharide (LPS) induced acute lung injury (ALI) in rats.Methods Forty male Wistar rats were randomly divided into three groups. The ALI model was reproduced by LPS intratracheal instillation; only saline was instilled intratracheally for control group. Rats in both model group and control group were sacrificed respectively at 1 hour and 8 hours (each n= 8). In HT group the body temperature was lowered to 32. 5 - 33.0 ℃ 1 hour after LPS instillation, and 8 rats were sacrificed st 8 hours. The arterial blood gas was determined in all the groups before and 1 hour and 8 hours after instillation of saline or LPS, and the oxygenation index (PaO2/FiO2) was calculated. The concentration of SP-A in bronchoalveolar lavage fluid (BALF) was determined by enzyme linked immunosorbent assay. The morphological changes in lung tissue of rats were observed under light microscope. Results At 1 hour after intratracheal instillation of LPS, the PaO2/FiO2 of each group reached the diagnostic criterion of ALI.Compared with control 1-hour group, the SP-A (μg/L) in BALF of model 1-hour group was decreased (53. 27±1.95 vs. 74. 81±6. 55, P＜0. 01); the SP-A in model 8-hour group and HT 8-hour group (4.35±2. 76 and 51.36±2. 33) was both obviously decreased compared with control 8-hour group (70. 81±-5. 01,both P＜0. 01). Compared with model 8-hour group, the SP-A of HT 8-hour group was obviously increased (P＜0. 01). Results of light microscopic examination, it was revealed that the alveolar structure of control 1-hour group and control 8-hour group was almost normal. Inflammatory response in lung tissues in model 8-hour group was found to be most serious; compared with model 8-hour group, inflammatory response in lung tissues in model 1-hour group and HT 8-hour group was reduced in certain degree. Conclusion A certain extent of HT may reduce lung injury of early endotoxin-induced ALI rats by delaying lowering of alveolar SP-A levels.     

亚低温在抑制小鼠脓毒症相关急性肾损伤中铁死亡的作用探究

目的：探讨亚低温是否通过激活核因子-E2相关因子2(Nrf2)抑制小鼠脓毒症相关急性肾损伤（S-AKI）中的铁死亡，从而发挥保护作用。方法：选择15只SPF级C57BL/6小鼠随机分为假手术组（S组）、脓毒症常温组（N组）、脓毒症亚低温组（H组），每组5只。盲肠结扎穿孔术建立小鼠脓毒症模型，分别对3组进行相应处理。苏木精—伊红（HE）染色观察小鼠肾组织损伤情况，酶标仪法测定血清尿素氮（BUN）及肌酐（Cr）水平、肾组织还原型谷胱甘肽（GSH）、丙二醛（MDA）含量，蛋白免疫印迹法（western blotting）和实时荧光定量PCR(RT-qPCR)测定肾组织酰基辅酶A合成酶长链家族成员4(ACSL4)、谷胱甘肽过氧化酶4(GPX4)、Nrf2及其下游因子血红素氧合酶1(HO-1)的蛋白及mRNA表达水平。结果：与S组比较，N组和H组肾组织病理有不同程度损伤，BUN、Cr水平升高，GSH含量减少，MDA含量增加，ACSL4蛋白及mRNA表达升高、GPX4蛋白及mRNA表达降低、Nrf2和HO-1蛋白及mRNA表达显著升高（均P<0.05）;H组与N组比较，病理损伤减轻，BUN、...     

重型及危重型新型冠状病毒感染的早期预测因素分析

目的 探讨引起新型冠状病毒感染（coronavirus disease 2019, COVID-19）向重型、危重型发展的早期预测因素。方法 选择2022年12月至2023年3月广西医科大学第一附属医院重症医学科、感染病区、呼吸与危重症医学科住院治疗的COVID-19患者为研究对象，按住院期间病情程度分为轻/中型组、重型组、危重型组。收集3组患者的一般临床资料和早期实验室检查结果并进行比较。结果 共纳入242例COVID-19患者，包括117例轻/中型患者，55例重型患者，70例危重型患者；男165例，女77例，中位年龄70(59,80)岁。三组患者在年龄、性别、糖尿病、心脏病、脑卒中、合并肺炎、合并血流感染、APACHEⅡ评分、入院时呼吸频率、收缩压以及早期白细胞计数（WBC）、淋巴细胞计数（LYM）、尿素、肌酐、白蛋白、C-反应蛋白、D-二聚体、降钙素原、白细胞介素-6(IL-6)比较差异有统计学意义（均P <0.05）。有序logistic回归显示，既往心脏病、脑卒中、合并血流感染、WBC、IL-6水平高、LYM水平低是重型、危重型COVID-19的独立危险因素[优势比（O...     

进行有创机械通气的成人危重型新型冠状病毒感染患者救治流程

早期恰当的有创机械通气是现行指南推荐的危重型新型冠状病毒感染（COVID-19）患者的重要救治手段之一，然而如何具体对有创机械通气危重型患者实施精准评估和有效治疗，对于实现整体救治成功率的提高，避免不同地区危重型患者有创机械通气临床救治质量的差异，减少治疗异质性，改善危重型新型冠状病毒感染患者预后，尤其是基层医院显得非常重要。为指导各地医院积极救治危重型新型冠状病毒感染患者，中国医药卫生事业发展基金会国家卫生健康技术推广应用服务粤港澳大湾区平台组织相关专家，根据国际、国内相关最新指南，编制进行有创机械通气的成人危重型新型冠状病毒感染患者救治流程。