鼻塞式持续气道正压通气联合肺表面活性物质治疗早产儿肺透明膜病对照研究

目的探讨鼻塞式持续气道正压通气(NCPAP)联合肺表面活性物质(PS)和NCPAP联合沐舒坦(MU)两种方法治疗早产儿肺透明膜病的疗效差异。方法将90例肺透明膜病(HMD)早产儿随机分为NCPAP联合PS(NC+PS治疗组)和NCPAP联合MU(NC+MU治疗组),分别进行治疗,并比较两组的疗效、动脉血气分析和近远期并发症的差异。结果 (NC+PS)组的总有效率显著高于(NC+MU)组,而在呼吸困难缓解时间、上呼吸机时间和平均住院时间方面均小于(NC+MU)组,两组间的差异具有统计学意义(P<0.05)。治疗前两组早产儿的pH、PaO2、PaCO2和PaO2/FiO2无统计学差异(P>0.05);治疗后,两组早产儿的pH、PaO2和PaO2/FiO2均逐渐升高,PaCO2逐渐降低,两组间的差异具有统计学意义(P<0.05)。近期并发症主要为肺炎、颅内出血和肺出血,远期并发症主要为脑性瘫痪、听力障碍和早产儿视网膜病,(NC+PS)组的早产儿在早期和远期并发症方面均显著低于(NC+MU)组(P<0.05)。结论 NCPAP联合PS能显著提高早产儿肺透明膜病疗效,近远期并发症低,疗效显著高于NCPAP联合MU的疗效。     

Cyclic Fatigue Resistance of Nickel-Titanium Instruments after Immersion in Irrigant Solutions with or without Surfactants

Introduction

The aim of the study was to assess cyclic fatigue resistance of reciprocating (Reciproc and WaveOne) and continuous rotating (ProTaper) nickel-titanium files after immersion in different irrigation solutions with or without surfactants during several short time periods.

Methods

A total of 270 new Reciproc R25, WaveOne Primary, and ProTaper F2 files were tested. Instruments of each brand were divided into 1 control group (n = 10) formed by new files and 4 test groups (n = 20) formed by instruments dynamically immersed at 37°C for 16 mm in 5.25% sodium hypochlorite (NaOCl), Hypoclean (5.25% NaOCl with surfactant), 17% EDTA, or EDTA Plus (17% EDTA with surfactant). Each test group was subdivided into 2 subgroups (n = 10) on the basis of the time of dynamic immersion in the endodontic irrigant solution (45 seconds or 3 minutes). Resistance to cyclic fatigue was determined by recording time to fracture in a stainless steel artificial canal with a 60° angle of curvature and 5-mm radius of curvature. The fracture surface was examined by using scanning electron microscopy.

Results

Immersion in NaOCl did not reduce the cyclic fatigue of reciprocating or continuous nickel-titanium files. The 17% EDTA reduced the fatigue resistance of all instruments after 3 minutes. The immersion in irrigants with surfactants did not influence the cyclic fatigue of instruments except for Reciproc immersed in Hypoclean solution.

Conclusions

EDTA immersion reduced the cyclic fatigue resistance of all instruments after 3 minutes. Addition of surfactants did not influence the cyclic fatigue of files except when added to NaOCl when it contacts Reciproc instruments.     

Surfactant does not improve survival rate in preterm infants with congenital diaphragmatic hernia

Background

Use of exogenous surfactant in congenital diaphragmatic hernia (CDH) patients is routine in many centers. The authors sought to determine the impact of surfactant use in the premature infant with CDH.

Methods

Data on liveborn infants with CDH from participating institutions were collected prospectively. Surfactant use and timing and outcome data were analyzed retrospectively. The authors evaluated the prenatal diagnosis patients as well. The outcome variable was survival to discharge. Odds ratios with confidence intervals were calculated.

Results

Five hundred ten infants less than 37 weeks’ gestation were entered in the CDH registry. Infants with severe anomalies (n = 80) were excluded. Information on surfactant use was available for 424 patients. Infants receiving surfactant (n = 209) had a greater odds of death than infants not receiving surfactant (n = 215, odds ratio, 2.17, 95% CI: 1.5 to 3.2; P < .01). In prenatally diagnosed infants with immediate distress, there was a trend toward worse survival rates among those receiving surfactant at 1 hour (52 patients) versus those that did not (93 patients; odds ratio, 1.93, 95% CI: 0.96 to 3.9; P < .07).

Conclusions

Surfactant, as currently used, is associated with a lower survival rate in preterm infants with CDH. The use of surfactant replacement in premature infants with CDH can be recommended only within the context of a randomized clinical trial.     

偏二甲基肼和四氧化二氮吸入性肺损伤中肺泡表面活性物质的变化

目的研究火箭液体推进剂偏二甲基肼（UDMH）和四氧化二氮（N2O4）吸入性急性肺损伤（ALI）中肺泡表面活性物质（PS）的变化及其与ALI的关系。方法84只大鼠分为对照组和5个实验组。实验组在静式染毒柜内分别吸入UDMH（0．98g／m^3）和N2O4（0．19g／ms）各10min，间隔10min。实验组在吸入后2、6、12、24、48h分别处死。测定各组大鼠常压下支气管肺泡灌洗液（BALF）的表面张力（γ）、加压下最低表面张力（γmin）、磷脂酰胆碱（PC）和磷脂酰乙醇胺（PE）。同时测定肺组织湿／于重比（W／D）、BALF中总蛋白和乳酸脱氢酶（LDH）等肺损伤指标，评价病理学改变。结果UDMH-N2O4吸入性ALI表现为肺W／D比值增加、BALF中总蛋白和LDH升高，以及肺水肿、肺间隔增厚等病理变化。PS的异常表现为：①在UDMH—N2O4吸入后2hBALF中γ和γmin。即明显升高，至24-48h尚未恢复到对照组水平；②吸入后24hBALF中PC明显低于对照组，PE含量明显高于对照组。以BALF中总蛋白作为肺损伤指标与PS异常的指标γ和γmin分别做直线相关分析，相关系数分别为0．435（P〈0．01）和0．419（P〈0．01）。结论UDMH—N2O4吸入性ALI中存在PS异常，PS异常可能参与了UDMH—N2O4吸入性ALI的发生发展过程。     

Innate immune molecule surfactant protein D attenuates sepsis‐induced acute kidney injury through modulating apoptosis and NFκB‐mediated inflammation

The objective of this study is to investigate the mechanism whereby innate immune molecule surfactant protein D (SP‐D) attenuates sepsis‐induced acute kidney injury (AKI) through modulating apoptosis and nuclear factor kappa‐B (NFκB)‐mediated inflammation. In the present study, a mouse sepsis model was established by cecal ligation and puncture in SP‐D knockout (KO) mice and wild‐type (WT) mice. A sham‐operated group was included as the control. The experimental materials were extracted 6 and 24 hours postoperatively. The plasma levels of tumour necrosis factor alpha (TNF‐α) and MCP‐1 were determined by enzyme‐linked immunosorbent assay (ELISA). Apoptosis was measured by double staining with Annexin V/propidium iodide and flow cytometry. The levels of NFκB in renal tissues were measured by ELISA and Western blotting assay. Apoptosis was detected by TUNEL assays. There were no significant differences in plasma TNF‐α levels between the WT sham group and the KO sham group at 6 and 24 hours postoperatively (P < .05), but the levels of TNF‐α in the WT sepsis and KO sepsis groups were significantly higher than those in controls (P < .05). The levels of TNF‐α in the KO sepsis group were significantly higher than those of the WT sepsis group (P < .05). TNF‐α levels in the WT sepsis group and the KO sepsis group at 24 hours postoperatively were significantly higher than those at 6 hours postoperatively (P < .05). The levels of MCP‐1 in the WT sepsis group and the KO sepsis group at 6 and 24 hours postoperatively were significantly higher than those in the control group (P < .05), and MCP‐1 levels in the KO sepsis group were significantly higher than those in the WT sepsis group (P < .05). MCP‐1 levels in the WT sepsis group and the KO sepsis group at 24 hours postoperatively were significantly higher than those at 6 hours postoperatively (P < .05). The expression of SP‐D in WT kidneys was significantly lower at 6 and 24 hours postoperatively (P < .05). The number of TUNEL‐positive cells in the kidneys from septic SP‐D KO mice was significantly higher (P < .05). The levels of NFκB in septic mice were significantly increased at 6 and 24 hours after induction of sepsis compared with the sham‐operated group compared with those of septic SP‐D KO mice and WT mice (P < .05). Innate immune molecule SP‐D significantly decreased plasma levels of inflammatory cytokines in mice and attenuated sepsis‐induced AKI by inhibiting NFκB activity and apoptosis.     

Pulmonary surfactant dysfunction in pediatric cystic fibrosis: Mechanisms and reversal with a lipid-sequestering drug

Background

Airway surfactant is impaired in cystic fibrosis (CF) and associated with declines in pulmonary function. We hypothesized that surfactant dysfunction in CF is due to an excess of cholesterol with an interaction with oxidation.

表面活性蛋白-A对脂多糖诱导的人肾小管近曲上皮细胞白介素-6表达的影响

目的：探讨表面活性蛋白-A（SP-A）的表达改变对脂多糖（LPS）诱导的人肾小管近曲上皮细胞（HK-2细胞）白介素-6（IL-6）表达的影响及机制。方法培养HK-2细胞,ELISA方法检测不同浓度的LPS（0、0．1、1、2、5、10 mg／L）作用8 h及5 mg／L的LPS于不同时间（0、2、4、8、16、24 h）作用HK-2细胞后IL-6蛋白表达的变化;应用脂质体转染法将SP-A SiRNA转染入HK-2细胞,筛选稳定转染细胞株,采用5 mg／L的LPS刺激SP-A SiRNA稳定转染的HK-2细胞8 h,ELISA方法检测细胞上清中IL-6的分泌量,Western印迹检测细胞NF-κB p65蛋白的表达。结果应用1、2、5、10 mg／L的LPS刺激HK-2细胞8 h后,IL-6蛋白表达水平较0、0．1 mg／L的LPS刺激后显著升高（P＜0．05）;同时,应用5 mg／L的LPS作用HK-2细胞4、8、16、24 h后,IL-6蛋白的表达水平较5 mg／L的LPS作用0、2 h显著升高（P＜0．05）。SP-A SiRNA转染的HK-2细胞经LPS刺激后,其NF-κBP65和IL-6蛋白表达较未转染经LPS刺激细胞明显升高（P＜0．05）。结论 SP-A可能通过抑制NF-κB p65的表达进而下调LPS诱导的HK-2细胞IL-6的表达,在脓毒症急性肾损伤时发挥保护作用。     

肺表面活性剂治疗21例新生儿呼吸窘迫综合征的临床观察

近几年，国内发达地区在治疗新生儿呼吸窘迫综合征（NRDS）时，应用肺表面活性制剂（PS），有较好的疗效。本院近两年也进行了该项治疗，现将PS治疗NRDS的疗效和安全性作一临床观察。     

前体脂质体型猪肺表面活性物质对整肺灌洗兔呼吸窘迫模型的治疗作用

目的：观察前体脂质体型猪肺表面活性物质（PPPS）对整肺灌洗兔呼吸窘迫模型的治疗作用。方法：将PPPS水化后，经气管滴入治疗整肺灌洗型成年兔呼吸窘迫模型，观察兔的生命体征、血气、动态肺顺应性等指标的变化。结果：整肺灌洗后模型兔的血气pH、PaO2急剧下降，PaCO2轻度上升，心率明显减慢而呼吸频率增加，SBP和DBP均明显下降；支气管肺泡灌洗液中PS含量明显下降；病理检查提示出现肺出血、肺不张、肺泡萎缩、透明膜形成等病变，符合Ⅰ型重症呼吸衰竭临床诊断标准。经气管滴入PPPS后，可以使RDS模型兔的各项指标（pH、PaO2、PaCO2、HR、BR、SBP、DBP）明显改善，肺部的病理改变也明显减轻。统计学分析结果提示，治疗组和对照组pH（F=4．572，P=0．046）、PaO2（F=557．586，P=0．000）、PaCO2（F=96．798，P：0．000）、TV（F=117．851，P=0．000）、Cydn（F=276．996，P=0．000）、HR（F=34．975，P=0．000）、BR（F=28．167,P=0．000）、SBP（F=124．751，P=0．000）和DBP（F=108．672，P=0．000）比较差异均有统计学意义；在治疗组中，各个时间点的pH、PaO2、PaCO2、TV、Cydn、HR、BR、SBP和DBP比较差异均有统计学意义。结论：PPPS对实验性PS缺乏和肺损伤造成的呼吸窘迫有显著的治疗作用。