呼吸图法制备基于准聚轮烷的响应性薄膜

响应性薄膜能够响应外界的刺激来改变自身的结构或性能,是智能材料的重要组成部分.本工作以1,4-二乙氧基柱[5]芳烃(1,4-diethoxypillar[5]arene,DEP5A)和聚己内酯-b-聚乙二醇-b-聚己内酯(PCL-b-PEG-b-PCL)构建的准聚轮烷(polypseudorotaxane,PPR)为原...     

Comparison of Targeted and Untargeted Approaches in Breath Analysis for the Discrimination of Lung Cancer from Benign Pulmonary Diseases and Healthy Persons

The aim of the present study was to compare the efficiency of targeted and untargeted breath analysis in the discrimination of lung cancer (Ca+) patients from healthy people (HC) and patients with benign pulmonary diseases (Ca−). Exhaled breath samples from 49 Ca+ patients, 36 Ca− patients and 52 healthy controls (HC) were analyzed by an SPME–GC–MS method. Untargeted treatment of the acquired data was performed with the use of the web-based platform XCMS Online combined with manual reprocessing of raw chromatographic data. Machine learning methods were applied to estimate the efficiency of breath analysis in the classification of the participants. Results: Untargeted analysis revealed 29 informative VOCs, from which 17 were identified by mass spectra and retention time/retention index evaluation. The untargeted analysis yielded slightly better results in discriminating Ca+ patients from HC (accuracy: 91.0%, AUC: 0.96 and accuracy 89.1%, AUC: 0.97 for untargeted and targeted analysis, respectively) but significantly improved the efficiency of discrimination between Ca+ and Ca− patients, increasing the accuracy of the classification from 52.9 to 75.3% and the AUC from 0.55 to 0.82. Conclusions: The untargeted breath analysis through the inclusion and utilization of newly identified compounds that were not considered in targeted analysis allowed the discrimination of the Ca+ from Ca− patients, which was not achieved by the targeted approach.     

Detection of exhaled gas by γ-graphyne and twin-graphene for early diagnosis of lung cancer: A density functional theory study

In lung cancer, primary diagnosis is quite essential to guarantee human health. In this work, the capability of γ-graphyne and twin-graphene sheets to detect typical breath gases such as benzene, styrene, aniline, and o-toluidine is studied based on density functional theory. The results indicate that these gases are physisorbed on γ-graphyne and twin-graphene. Because of relatively low gas binding strength between gases and γ-graphyne and twin-graphene, these sheets can be proper for the practical gas sensors with a fast recovery rate. Both γ-graphyne and twin-graphene have semiconducting properties before and after gas adsorption. Adsorption of the gases decreases the energy band gap, and increases the electric dipole moment of γ-graphyne and twin-graphene. The electronic properties of twin-graphene are more sensitive than that of γ-graphyne to the presence of the considered gases. Hence, twin-graphene can be desirable and promising material for sensing typical breath gases to diagnose lung cancer.     

Determination of hexavalent chromium in exhaled breath condensate and environmental air among chrome plating workers

Chromium speciation has attracted attention because of the different toxicity of Cr(III), which is considered relatively non-toxic, and Cr(VI), which can cross cell membranes mainly as a chromate anion and has been classified as a class I human carcinogen. The aims of the present study were to measure soluble Cr(VI) levels in environmental samples, to develop a simple method of quantifying Cr(VI) in exhaled breath condensate (EBC), and to follow the kinetics of EBC Cr(VI) in chrome plating workers.Personal air samples were collected from 10 chrome platers; EBC was collected from the same workers immediately after the work shift on Tuesday and before the work shift on the following Wednesday. Environmental and EBC Cr(VI) levels were determined by means of colorimetry and electrothermal absorption atomic spectrometry, respectively.The method of detecting Cr(VI) in environmental air was based on the extraction of the Cr(VI)-diphenylcarbazide (Cr(VI)-DPC) complex in 1-butanol, whereas EBC Cr(VI) was determined using a solvent extraction of Cr(VI) as an ion pair with tetrabutylammonium ion, and subsequent direct determination of the complex (Cr(VI)-DPC) in EBC.Kinetic data showed that airborne Cr(VI) was reduced by 50% in airway lining fluid sampled at the end of exposure and that there was a further 50% reduction after about 15 h. The persistence of Cr(VI) in EBC supports the use of EBC in assessing target tissue levels of Cr(VI).     

Investigation of acetone,butanol and carbon dioxide as new breath biomarkers for convenient and noninvasive diagnosis of obstructive sleep apnea syndrome

The objective of the present study was to investigate whether analysis of carbon dioxide, acetone and/or butanol present in human breath can be used as a simple and noninvasive diagnosis method for obstructive sleep apnea syndrome (OSAS). For this purpose, overnight changes in the concentrations of these breath molecules were measured before and after sleep in 10 patients who underwent polysomnography and were diagnosed with OSAS, and were compared with the levels of these biomarkers determined after sleep in 10 healthy subjects. The concentrations of exhaled carbon dioxide were measured using external cavity laser‐based off‐axis cavity enhanced absorption spectroscopy, whereas the levels of exhaled acetone and butanol were determined using thermal desorption gas chromatography mass spectrometry. We observed no significant changes in the levels of exhaled acetone and carbon dioxide in OSAS patients after sleep compared with pre‐sleep values and compared with those in healthy control subjects. However, for the first time, to our knowledge, analyses of expired air showed an increased concentration of butanol after sleep compared with that before sleep and compared with that in healthy subjects. These results suggest that butanol can be established as a potential biomarker to enable the convenient and noninvasive diagnosis of OSAS in the future.     

电喷雾萃取电离质谱直接检测人体呼出气体中的乙腈

人体呼出气体携带大量的生理病理信息,在临床诊断和代谢组学研究中发挥着日益重要的作用。本研究在未对样品进行预处理条件下,采用电喷雾萃取电离质谱(EESI-MS)技术直接测定呼出气体中乙腈分子。在优化的实验条件下,结合多级串联质谱,有效地获得了人体呼出气体中乙腈含量的信息。对气相乙腈的检出限为5.71 pL/L,线性范围为76.4～1910 pL/L。以两名健康志愿者呼出气体为实例,实际检测了其中乙腈的含量分别为134.49和104.40 pL/L,相对标准偏差(RSD)分别为6.3%和7.2%。结果表明,本方法灵敏度高、精密度好、分析速度快、特异性强,能够承受呼出气体中复杂基体的影响,适合于呼出气体中痕量乙腈的直接半定量检测,也可为呼出气体中其它小分子物质的检测提供新思路。     

静滴芬太尼引起呼吸停止一例

报道了静滴芬太尼引起呼吸停止一例，对该病例进行了讨论，提出了注意事项。     

Simultaneous determination of the advanced glycation end product <Emphasis Type="Italic">N</Emphasis><Superscript>ɛ</Superscript>-carboxymethyllysine and its precursor,lysine, in exhaled breath condensate using isotope-dilution–hydrophilic-interaction liquid chromatography coupled to tandem mass spectrometry

Analysis of biomarkers in exhaled breath condensate (EBC) is a non-invasive method for investigating the effects of different diseases or exposures, on the lungs and airways. N ^ɛ-carboxymethyllysine (CML) is an important biomarker of advanced glycation end products (AGEs). A method has been developed for simultaneous determination of CML and its precursor, the amino acid lysine, in exhaled breath condensate (EBC). After addition of labelled internal standards (d-4-CML; d-4-lysine), the EBC was concentrated by freeze-drying. Separation and detection of the analytes were performed by hydrophilic-ion liquid chromatography coupled with tandem mass-spectrometric detection (HILIC–MS–MS). The limits of quantification were 10 pg mL⁻¹ EBC and 0.5 ng mL⁻¹ EBC for CML and lysine, respectively. The relative standard deviation of the within-series precision was between 2.8 and 7.8% at spiked concentrations between 40 and 200 pg mL⁻¹ for CML and between 6 and 20 ng mL⁻¹ for lysine. Accuracy for the analytes ranged between 89.5 and 133%. The method was used for the analysis of EBC samples from ten healthy persons from the general population and ten persons receiving dialysis. CML and lysine were detected in all EBC samples with median values of 19 pg mL⁻¹ CML and 11.9 ng mL⁻¹ lysine in EBC of healthy persons and 25 pg mL⁻¹ CML and 9.5 ng mL⁻¹ lysine in EBC of dialysis patients.     

Directional Photomanipulation of Breath Figure Arrays

Porous polymeric films are of paramount importance in many areas of modern science and technology. However, processing methods typically based on direct writing, imprint, and lithography techniques have low throughput and are often limited to specific fabricated shapes. Herein, we demonstrate the directional photomanipulation of breath figure arrays (BFAs) formed by an azobenzene‐containing block copolymer to address the aforementioned problems. Under the irradiation of linearly polarized light, the round pores in the BFAs were converted to rectangular, rhombic, and parallelogram‐shaped pores in 30 min, due to the anisotropic mass migration based on the photo‐reconfiguration of the azobenzene units. Through a secondary irradiation after rotating the sample by 90°, the transformed pores were apparently recovered. Therefore, this non‐contacted, directional photomanipulation technique in conjunction with breath figure processing opens a new route to nano/microporous films with finely tuned features.     

Breath figures method to control the topography and the functionality of polymeric surfaces in porous films and microspheres

Polymeric films with porous structures and microsphere patterns were prepared by the method of breath figures, mixing poly(methyl methacrylate) (PMMA) and amphiphilic copolymers containing glucose moieties in their structure, glycopolymers. Statistical and block glycopolymers were used in a proportion of 10 wt %. The statistical glycopolymers were synthesized via conventional free radical copolymerization, whereas the block copolymer of methyl methacrylate and 2‐{[(D ‐glucosamin‐2‐Nyl) carbonyl]oxy}ethyl methacrylate, PMMA‐b‐PHEMAGl, was obtained by atom transfer radical polymerization. Glycopolymers were blended with a high molecular weight PMMA matrix and dissolved in a mixture of tetrahydrofuran and a small amount of water. Results showed that, depending on experimental conditions (water content, humidity, and type of copolymer), the observed final film morphology changes significantly. Thus, films with honeycomb pattern structures, spherical particles, or a mixture of both were obtained. In addition, polar glucose moieties were oriented principally either inside of the pores in the case of films and towards the surface in the case of particles. The specific surface bioactivity of these materials was examined using the specific lectin concanavalin A conjugated with fluorescein, Con A‐FITC. The successful binding of the Con A was demonstrated by fluorescence microscopy being more intense at the surface of the pores and of the particles. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012