In situ measurements of human cough aerosol hygroscopicity

The airborne dynamics of respiratory droplets, and the transmission routes of pathogens embedded within them, are governed primarily by the diameter of the particles. These particles are composed of the fluid which lines the respiratory tract, and is primarily mucins and salts, which will interact with the atmosphere and evaporate to reach an equilibrium diameter. Measuring organic volume fraction (OVF) of cough aerosol has proved challenging due to large variability and low material volume produced after coughing. Here, the diametric hygroscopic growth factors (GF) of the cough aerosol produced by healthy participants were measured in situ using a rotating aerosol suspension chamber and a humidification tandem differential mobility analyser. Using hygroscopicity models, it was estimated that the average OVF in the evaporated cough aerosol was 0.88 ± 0.07 and the average GF at 90% relative humidity (RH) was 1.31 ± 0.03. To reach equilibrium in dry air the droplets will reduce in diameter by a factor of approximately 2.8 with an evaporation factor of 0.36 ± 0.05. Hysteresis was observed in cough aerosol at RH = ∼35% and RH = ∼65% for efflorescence and deliquescence, respectively, and may depend on the OVF. The same behaviour and GF were observed in nebulized bovine bronchoalveolar lavage fluid.     

Histamine determination in tears as an index of safety in use of cosmetic products

To assess ocular irritancy caused by chemical and cosmetic products a reliable method based on evaluation of histamine (Hm) in tears is presented. Hm is measured at picomole levels by HPLC and fluorimetric detection after fluorescamine-HM derivatization. In order to avoid any uncontrolled irritation and stimulation of the conjunctiva during sample collection, a procedure of conjunctiva lavage was developed. A balanced salt solution (50 μl) containing a known amount of Hm-fluorophore as reference standard is instilled in the conjunctiva fornix. After a few seconds 20 μl of tear fluid is collected: 10 μl are immediately analysed and 10 μl after derivatization reaction. In this way it is possible to evaluate tear dilution and to assess Hm content in less than 10 minutes.
In a group of 20 normal subjects Hm has been determined in comparison with that of two volunteers after topical application of 50 μ of 0.2% and 0.4% sodium lauryl sulphate solution. A contact of 30 seconds of the cosmetic ingredient caused an immediate dose-dependent Hm release through a direct cytotoxic damage of cell membranes due to the surfactant action.
Évaluation de l'irritation occulaire due aux cosmétiques par la détermination de l'histamine lacrimale     

Lactoperoxidase-mediated degradation of single-walled carbon nanotubes in the presence of pulmonary surfactant

Carbon nanotubes (CNTs) may elicit inflammatory responses following pulmonary exposure. Conversely, enzymatic biodegradation of CNTs by inflammatory cells has also been reported. The aim of this study was to study the degradation of oxidized single-walled CNTs (ox-SWCNTs) by lactoperoxidase (LPO), a secreted peroxidase present in the airways, and whether pulmonary surfactant affects this biodegradation. To this end, ox-SWCNTs were incubated in vitro with recombinant bovine LPO + H₂O₂ + NaSCN in the presence and absence of porcine lung surfactant (Curosurf®) and biodegradation was monitored using UV–Vis–NIR spectroscopy, Raman spectroscopy, and scanning electron microscopy. The interaction of recombinant LPO with bundles of ox-SWCNTs was confirmed by atomic force microscopy. Cell-free biodegradation of ox-SWCNTs was also observed ex vivo in murine bronchoalveolar lavage fluid in the presence of H₂O₂ + NaSCN. Our study provides evidence for biodegradation of ox-SWCNTs with a lung surfactant ‘bio-corona’ and expands the repertoire of mammalian peroxidases capable of biodegradation of ox-SWCNTs. These findings are relevant to inhalation exposure to these materials, as LPO serves as an important component of the airway defense system.     

Some Characteristics of Free Cell Population in the Airways of Rats after Intratracheal Instillation of Copper-Containing Nano-Scale Particles

We used stable water suspensions of copper oxide particles with mean diameter 20 nm and of particles containing copper oxide and element copper with mean diameter 340 nm to assess the pulmonary phagocytosis response of rats to a single intratracheal instillation of these suspensions using optical, transmission electron, and semi-contact atomic force microscopy and biochemical indices measured in the bronchoalveolar lavage fluid. Although both nano and submicron ultrafine particles were adversely bioactive, the former were found to be more toxic for lungs as compared with the latter while evoking more pronounced defense recruitment of alveolar macrophages and especially of neutrophil leukocytes and more active phagocytosis. Based on our results and literature data, we consider both copper solubilization and direct contact with cellular organelles (mainly, mitochondria) of persistent particles internalized by phagocytes as probable mechanisms of their cytotoxicity.     

Identification of Oxidative Stress Related Proteins as Biomarkers for Lung Cancer and Chronic Obstructive Pulmonary Disease in Bronchoalveolar Lavage

Lung cancer (LC) and chronic obstructive pulmonary disease (COPD) commonly coexist in smokers, and the presence of COPD increases the risk of developing LC. Cigarette smoke causes oxidative stress and an inflammatory response in lung cells, which in turn may be involved in COPD and lung cancer development. The aim of this study was to identify differential proteomic profiles related to oxidative stress response that were potentially involved in these two pathological entities. Protein content was assessed in the bronchoalveolar lavage (BAL) of 60 patients classified in four groups: COPD, COPD and LC, LC, and control (neither COPD nor LC). Proteins were separated into spots by two dimensional polyacrylamide gel electrophoresis (2D-PAGE) and examined by matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF/TOF). A total of 16 oxidative stress regulatory proteins were differentially expressed in BAL samples from LC and/or COPD patients as compared with the control group. A distinct proteomic reactive oxygen species (ROS) protein signature emerged that characterized lung cancer and COPD. In conclusion, our findings highlight the role of the oxidative stress response proteins in the pathogenic pathways of both diseases, and provide new candidate biomarkers and predictive tools for LC and COPD diagnosis.     

肺部感染肺泡灌洗液中非发酵菌分布及耐药性分析

目的：对肺部感染患者支气管肺泡灌洗液（BALF）培养,分析检出非发酵菌感染及其耐药情况,以指导临床合理使用抗菌药物。方法对2008年5月至2013年6月中国人民武装警察部队陕西省总队医院检验科从BALF中分离的非发酵菌的分布及耐药性进行回顾性分析。结果共检出93株非发酵菌,检出率居前4位的依次为铜绿假单胞菌（48/93,51．61％）、鲍曼不动杆菌（31/93,33．33％）、嗜麦芽寡养单胞菌（10/93,10．75％）、醋酸钙不动杆菌（2/93,2．15％）;非发酵菌对不同抗菌药物呈多重耐药性,碳青霉烯类、头孢哌酮/舒巴坦、多黏菌素对非发酵菌的作用较好。结论肺部感染支气管肺泡灌洗液中非发酵菌具有较高的检出率和耐药性,应加强临床肺泡灌洗液的细菌学检测,按照药敏试验结果合理用药。     

Bronchoalveolar lavage and its role in diagnosing cobalt lung disease

The bronchoalveolar lavage (BAL) of two groups of hard metal workers (11 subjects) were examined and compared with BALs of 14 unexposed individuals as controls. The first group of workers included five asymptomatic subjects (2 females and 3 males) with normal lung function tests and chest X-rays. All the workers had been exposed daily to hard metal dust for 5 years before fiberoptic bronchoscopy. The second group of workers included six individuals (1 female and 5 males) with cobalt lung disease at biopsy. The BAL's cytology at the deep lung level is in agreement with a possible immunologic pathogenesis of the lung disease, similar to hypersensitivity pneumonitis (lymphocytosis with helper-suppressor ratio reduction). In order to identify diagnostic key-parameters, the data presented here are compared with data reported in literature for workers with a history of hard metal or cobalt (alone) exposure. Although the BAL can be useful, for a better definition of the reaction at the deep lung level, it seems insufficient per se for the diagnosis of hard metal lung disease.     

Balb/c小鼠花生过敏模型的建立及发病机理

通过皮下注射花生粗蛋白的致敏方式,建立Balb/c小鼠花生过敏模型,探讨食物过敏的发病机制.将16只Balb/c小鼠(雌性)分为PBS对照组和模型组,利用伊红苏木精(haematoxylin and eosin,H&E)染色,用透射电镜观察小鼠肠道炎症和肠绒毛病理变化,发现花生过敏模型组较PBS对照组可见小肠黏膜水肿和炎症细胞浸润,组肠微绒毛严重损伤;通过伊文思蓝尾静脉注射,模型组中小鼠足部出现明显蓝色,而对照组无明显变化;模型组腹腔灌洗液细胞相对PBS对照组炎症细胞数目显著增加,主要以嗜酸性粒细胞、淋巴细胞和肥大细胞为主,且肥大细胞活化状态明显;酶联免疫吸附法检测发现,血清中IgE、IL-4、IL-5、IL-6和组胺的水平及腹腔上清液组胺的水平,模型组明显高于对照组(P<0.05),IgG2a和IFN-γ的水平模型显著低于PBS对照组(P<0.01).花生模型组较对照组出现一系列的过敏病理变化,为开发治疗花生过敏药物提供了良好的动物模型.     

Effect of moisture‐damage intervention on the immunotoxic potential and microbial content of airborne particles and on occupants' upper airway inflammatory responses

This intervention study evaluated the effect of moisture‐damage repairs on the exposure and on the upper airway inflammatory responses of the occupants. The airborne microbial exposure was followed by quantitative PCR analyses of 13 microbial species in repeated long‐term indoor air samples before (N = 26) and after (N = 28) repairs of the school building. Airborne particulate matter was collected similarly from the same premises (before N = 25, after N = 34) for determination of nitric oxide (NO), tumor necrosis factor α (TNFα), and interleukin‐6 (IL‐6), measured in the cell culture medium of mouse macrophages. NO, TNFα, IL‐6, and IL‐4 were also analyzed in the nasal lavage (NAL) samples of the occupants (N = 13) to characterize their upper airway inflammatory responses during the exposure and after its cessation. After the repairs, concentrations of the measured airborne microbes decreased, the difference being significant for six of 13 species. After renovation, airborne particulate matter also caused significantly lower production of IL‐6 and TNF‐α in mouse macrophages than the material collected before the renovation. The concentration of IL‐4 in the NAL samples was significantly lower after the renovation. These results show that the inflammatory potential of the airborne material decreases after intensive repair of the moisture damage.     

全肺灌洗治疗兔肺纤维化的病理观察

目的通过观察兔肺组织的病理改变,探讨全肺灌洗治疗兔肺纤维化的效果。方法将25只健康新西兰大白兔按随机数字表法分成3组,对照组（n=5）、模型组（n=5）和实验组（n=15）。又将实验组分为3个亚组（7 d组1、4 d组2、1 d组）,每组各5只。对照组经气管内注入生理盐水2 mL;模型组和实验组经气管内一次性注入平阳霉素制备肺纤维化模型。7 d组、14 d组、21 d组分别在动物模型制备后的第7、14、21天进行全肺灌洗治疗。在第5周末经腹主动脉放血将兔处死,取肺组织行HE染色检查,按Szapiel的方法评价肺组织病理改变,比较各组肺组织纤维化严重程度。结果兔肺组织病理：对照组无肺泡炎及肺纤维化;模型组和21 d组均为重度肺纤维化;7 d组1只轻度肺纤维化,4只中度肺纤维化;14 d组2只中度肺纤维化,3只重度肺纤维化。兔肺组织病理改变严重程度：模型组、7 d组2、1 d组、14 d组重于对照组（P〈0.05或P〈0.01）;7 d组轻于模型组、21 d组（P〈0.05）;14 d组、21 d组与模型组比较差异无统计学意义（P〉0.05）。结论在肺泡炎期行全肺灌洗治疗有助于延缓兔肺纤维化的发展。