急性肺损伤/急性呼吸窘迫综合征（ALI/ARDS）是指心源性以外的各种肺内外致病因素导致的原发或继发的急性、进行性呼吸衰竭，其病理改变主要表现为肺上皮及内皮细胞的损伤、炎性浸润和透明膜形成，并伴有肺间质纤维化。临床表现为以呼吸窘迫、顽固性低氧血症和非心源性肺水肿为特征的一种急性进行性呼吸困难。采用常规的治疗难以纠正其低氧血症，死亡率高达60%，严重威胁人们的生命健康[1]。自1967年Ashbaugh及其同事首次描述ALI/ARDS以来，医学研究者进行了大量关于ALI/ARDS发病机制及病理生理学的基础及临床研究，但是迄今ALI/ARDS的发病机理仍未完全阐明。近年来越来越多的研究提示凋亡因子（Fas/Fas配体，即Fas/FasL）介导的细胞凋亡在ALI/ARDS的发生发展过程中有着十分重要的作用[2，3]。本文就Fas/FasL的生物学特性及其在ALI/ARDS发病机制中的作用作一综述。
Objective To observe the effects of hydrogen peroxide on the expression of transforming growth factorβ1(TGF-β1) and Smad3 protein in A549 cells. Methods A549 cells were cultured with different concentrations of hydrogen peroxide. MTT assay was used to determine the cell growth and survival rates. The level of TGF-β1 and p-Smad3 protein were detected by western blotting. Results It was observed that hydrogen peroxide significantly inhibit proliferation of A549 cells. When the concentration of hydrogen peroxide was 1.0 mmol/L, the inhibition ratio reaches 46.34%, and the level of TGF-β1 and p-Smad3 protein were increased in a time-dependence manner and reached a peak after 24 h, then decreased a little but also remained at high level. Conclusions In the early oxidative damage, A549 cells express high level of TGF-β1 and p-Smad3 protein. It may be relevant to tissue repair and remodeling after lung injury.
ObjectiveTo explore the value of inferior vena cava inspiratory collapsibility (ΔIVC) in guiding septic shock resuscitation with early goal-directed therapy (EGDT).MethodsA single center, randomized controlled trial was conducted at an 812-bed hospital in Mianyang, Sichuan. Adult patients with early septic shock in the intensive care unit were assessed and treated at defined intervals over 6 h using an ΔIVC-guided resuscitation protocol or an EGDT protocol. Feasibility outcomes were fluid balance and norepinephrine administration. The primary clinical outcomes were in-hospital mortality rate, 90-day survival rate. Secondary outcomes included incidence of acute kidney injury and consumption of health resources.ResultsSixty-eight patients with septic shock were enrolled in this study. Baseline characteristics were similar between the two groups. The ΔIVC-guided septic shock resuscitation group was lower than the EGDT group in the ICU 24 h fluid replacement (L): 3.8 (4.0, 5.3) vs. 4.7 (4.0, 6.6), 72 h liquid positive balance (L): 0.2 (–0.65, 1.2) vs. 2.5 (0.0, 4.1), intensive care unit length of stay (d): 7.5 (5.0, 14.0) vs. 15.0 (7.0, 21.5), mechanical ventilation cumulative time (d): 3.0 (0.0, 7.0) vs. 7.5 (2.2, 12.0), ICU costs (ten thousand yuan): 3.4 (2.1, 5.9) vs. 8.6 (4.2, 16.5), bedside blood purification treatment costs (ten thousand yuan): 2.3 (1.1, 3.3) vs. 6.8 (2.1, 10.0) (P<0.05). No difference was observed in the incidence of acute kidney injury (P > 0.05), in-hospital mortality and 90-day survival between the two groups (log-rank χ2=0.35, P>0.05).ConclusionsAmong patients with septic shock, a ΔIVC-guided septic shock resuscitation, compared with EGDT, did not reduce in-hospital mortality. It might prevent the risk of over resuscitation, shorten the duration of mechanical ventilation, and lead to a better utilization of intensive care unit resources.