Modulation of ENaC,CFTR, and iNOS expression in bronchial epithelial cells after stimulation with Staphylococcus epidermidis (94B080) and Staphylococcus aureus (90B083)

Bacteria affect the respiratory epithelium, which is covered by airway surface liquid (ASL) and mucus. Ion concentrations in the ASL are determined by the cystic fibrosis transmembrane conductance regulator (CFTR) and the epithelial Na⁺ channel (ENaC). Neonatal sepsis is a major risk factor for subsequent pulmonary disease in preterm newborns. Predominating are coagulase‐negative staphylococci (e.g., Staphylococccus epidermidis and Staphylococccus aureus). The aim of this study was to investigate modulation of CFTR, ENaC, mucins, proinflammatory cytokines, and inducible nitric oxide synthase (iNOS) in respiratory epithelial cells after S. epidermidis 94B080 and S. aureus 90B083 exposure. Bronchial epithelial cells were incubated with S. epidermidis 94B080 and S. aureus 90B083 (neonatal blood isolates) for 1–36 h. Expression of CFTR, ENaC, iNOS, and mucins was analyzed by real‐time PCR and Western blotting. Release of cytokines was analyzed by ELISA, and production of NO by the Griess assay. Expression of CFTR significantly decreased after 36 h incubation with S. epidermidis and more prominently with S. aureus, whereas S. epidermidis caused a significant increase in the expression of β‐ and γ‐ENaC. Expression of iNOS increased, but NO was not detected. Both staphylococci caused a decrease in the intracellular Ca²⁺ concentration. S. aureus induced increased secretion of IL‐6, IL‐8, and transforming nuclear factor (TNF)‐α in a time‐dependent manner as compared with S. epidermidis. In conclusion, expression of ENaC, CFTR, and iNOS is modulated by exposure to S. aureus 90B083 and S. epidermidis 94B080. S. aureus is more potent in causing release of IL‐6, IL‐8, and TNF‐α by bronchial epithelial cells as compared with S. epidermidis. The mRNA expression for the mucus proteins MUC2, MUC5AC, and MUC5B could not be measured, neither in the presence nor in the absence of bacteria.     

Developmental anatomy of the airway

The airway develops from the primitive foregut at 4 weeks’ gestation. Congenital anomalies may result when this process is abnormal. The anatomy of the airway at birth is uniquely different from older children and adults, with a large tongue, long floppy epiglottis, large occiput and cephalad larynx. These features affect the technique required for facemask ventilation, supraglottic airway use and endotracheal intubation. A neutral head position and straight-bladed laryngoscope are usually used for intubation. Neonates are also obligate nasal breathers and simultaneously suckle and breath. Minute volume is rate dependent and the highly compliant chest easily displays sternal and intercostal recession during respiratory distress, and early onset of fatigue. From the neonatal period onwards the anatomy gradually begins to resemble that of adults. The cricoid descends caudally, the epiglottis becomes firmer and shorter, and the relatively large occiput recedes. The conventional wisdom of the cricoid ring being the narrowest part of the paediatric airway is not supported by contemporary investigation. The consequence of these findings on endotracheal tube selection and the rationale for increasing use of cuffed endotracheal tubes in children is discussed.     

Cadmium,smoking, and reduced levels of exhaled nitric oxide among US adults

Exposure to cadmium is known to be associated with reducing nitric oxide (NO) production in experimental conditions, but few studies have examined the association between environmental cadmium exposures and exhaled NO in human. We examined the association between blood cadmium levels and exhaled NO levels in a representative sample of US adults. This investigation was a cross-sectional study of 7813 adults (≥20 years) who participated in the 2007–2008 and 2009–2010 National Health and Nutrition Examination Survey and had their exhaled NO and blood cadmium measurements recorded. The geometric means of the exhaled NO and blood cadmium levels were 13.3 ppb (95% CI: 12.7, 13.9) and 0.51 μg/dL (95% CI: 0.48, 0.54), respectively. Higher blood cadmium levels were associated with decreased exhaled NO levels after adjusting for potential confounding variables. Additionally, a two-fold increase in the blood cadmium levels was associated with a 5% decrease in the exhaled NO levels. The results were significant regardless of the subjects’ smoking status or serum cotinine levels, although the percent changes in the exhaled NO levels differed depending on the extent of smoking.Our findings suggest that blood cadmium levels may be associated with reduced levels of exhaled NO in a general sample of US adults. Moreover, cadmium may partially mediate the effect of smoking on exhaled NO production.     

气管插管全麻术中预防气道感染的临床研究

目的观察一次性病毒/细菌过滤器在气管插管全麻术中预防气道感染的应用价值,为临床预防策略的制定提供参考。方法选择2011年3月-2013年3月接受气管插管全麻手术的患者76例,按照随机数字表法将其分为观察组和对照组各38例;观察组应用一次性病毒/细菌过滤器,而对照组则未用,分别在麻醉前和手术结束时用无菌棉签采集麻醉机呼气端、吸气端表面标本行细菌学检测;在手术结束时收集钠石灰罐底部10g钠石灰行细菌学检测,对比两组患者的检测结果和术后24h内气道感染发生率。结果两组患者在麻醉开始前麻醉机呼气端、吸气端细菌学培养结果均为阴性;手术结束时,麻醉机吸气端、呼气端和钠石灰的细菌学培养阳性率均为0,对照组分别为5.26%、42.11%和15.79%,观察组细菌培养阳性率均显著低于对照组,差异有统计学意义(P<0.05);术后24h内气道感染发生率观察组为2.63%,显著低于对照组的18.62%,差异有统计学意义(P<0.05)。结论麻醉机气管插管全麻可增加患者气道感染的机会,通过一次性病毒/细菌过滤器、及时更换钠石灰等措施,可有效预防气道感染的发生。     

Changes in sputum cytology,airway inflammation and oxidative stress due to chronic inhalation of biomass smoke during cooking in premenopausal rural Indian women

To perform sputum analysis for verification of pulmonary changes in premenopausal rural Indian women chronically exposed to biomass smoke during cooking.Three consecutive morning sputum samples were collected from 196 women (median age 34 years) cooking with biomass and 149 age-matched control women cooking with cleaner fuel liquefied petroleum gas. Smears made on slides were stained with Papanicolaou and Perl's Prussian blue. Airway oxidative stress was estimated as reactive oxygen species (ROS) generation (by flow cytometry) and superoxide dismutase (SOD) level (by spectrophotometry) in sputum cells. Airway inflammation was measured as sputum levels of interleukin (IL)-6, -8 and tumor necrosis factor- alpha (TNF-α). Particulate matter of diameter less than 10 (PM₁₀) was measured using laser photometer while benzene exposure was monitored by measuring trans, trans-muconic acid (t,t-MA) in urine by HPLC-UV. Compared with control, sputum of biomass users contained more neutrophils, lymphocytes, eosinophils, alveolar macrophages, and showed presence of ciliocytophthoria, Charcot-Leyden crystals, Curschmann's spiral. ROS generation was increased by 2-fold while SOD was depleted by 31% in biomass users. They also had higher sputum levels of IL-6, -8 and TNF-α. Levels of PM₁₀ and t,t-MA were 2.9- and 5.8-times higher in biomass-using women. PM₁₀ and t,t-MA levels were positively associated with cellular changes in the sputum, markers of airway inflammation, and oxidative stress. Cooking with biomass alters sputum cytology, and increases airway inflammation and oxidative stress that might result in further amplification of the tissue damaging cascade in women chronically exposed to biomass smoke.     

Understanding and improving airway management in companion animals – Part 2

This article reviews alternatives to endotracheal tubes for airway management in veterinary patients under anaesthesia. Anaesthesia has had many improvements over the past few decades and now airway management is finally catching up and so veterinary anaesthetists have a wider choice of options. As in other areas of anaesthesia, airway management should not be a one-size-fits-all approach. Patient and procedure should be considered before selecting the most appropriate airway device.     

前列腺源性ETS因子在哮喘及鼻黏膜炎性疾病中的研究进展

含SAM尖端结构域的E26转化特异性因子(SPDEF)是ETS转录因子家族的最新成员之一, SPDEF又称为前列腺源性ETS因子(PDEF),首次发现其在前列腺癌中高度表达,参与肿瘤细胞的增殖分化、迁移凋亡和血管形成。近年来研究发现SPDEF与杯状细胞增生和分化密切相关,是调控呼吸道黏液高分泌的核心因子。对SPDEF调控黏液高分泌的机制及其在呼吸道慢性炎性疾病中的研究进展做一综述,以期为呼吸道黏液高分泌疾病的发病机制和诊治提供新思路。     

重症甲型H1N1流感患者的气道管理

<正>甲型H1N1流感是由甲型H1N1流感病毒感染引起的急性呼吸系统传染病。少数病例病情进展迅速,出现呼吸衰竭、多脏器功能不全或衰竭。这些病人除需一般抗病毒治疗外,常需要机械通气治疗。