1
|
Nwoba ST, Carere CR, Wigley K, Baronian K, Weaver L, Gostomski PA. Using RNA-Stable isotope probing to investigate methane oxidation metabolites and active microbial communities in methane oxidation coupled to denitrification. CHEMOSPHERE 2024; 357:142067. [PMID: 38643845 DOI: 10.1016/j.chemosphere.2024.142067] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/14/2024] [Revised: 03/26/2024] [Accepted: 04/15/2024] [Indexed: 04/23/2024]
Abstract
The active denitrifying communities performing methane oxidation coupled to denitrification (MOD) were investigated using samples from an aerobic reactor (∼20% O2 and 2% CH4) and a microaerobic reactor (2% O2, 2% CH4) undertaking denitrification. The methane oxidation metabolites excreted in the reactors were acetate, methanol, formate and acetaldehyde. Using anaerobic batch experiments supplemented with exogenously supplied 13C-labelled metabolites, the active denitrifying bacteria were identified using 16S rRNA amplicon sequencing and RNA-stable isotope probing (RNA-SIP). With the aerobic reactor (AR) samples, the maximum NO3- removal rates were 0.43 mmol g-1 d-1, 0.40 mmol g-1 d-1, 0.33 mmol g-1 d-1 and 0.10 mmol g-1 d-1 for exogenously supplied acetate, formate, acetaldehyde and methanol batch treatments respectively, while with the microaerobic reactor (MR) samples, the maximum NO3- removal rates were 0.41 mmol g-1 d-1, 0.33 mmol g-1 d-1, 0.38 mmol g-1 d-1 and 0.14 mmol g-1 d-1 for exogenously supplied acetate, formate, acetaldehyde and methanol batch treatments respectively. The RNA-SIP experiments with 13C-labelled acetate, formate, and methanol identified Methyloversatilis, and Hyphomicrobium as the active methane-driven denitrifying bacteria in the AR samples, while Pseudoxanthomonas, Hydrogenophaga and Hyphomicrobium were the active MOD bacteria in the MR samples. Collectively, all the data indicate that formate is a key cross-feeding metabolite excreted by methanotrophs and consumed by denitrifiers performing MOD.
Collapse
Affiliation(s)
- Sunday T Nwoba
- Dept. of Chemical & Process Engineering, University of Canterbury, Christchurch, New Zealand.
| | - Carlo R Carere
- Dept. of Chemical & Process Engineering, University of Canterbury, Christchurch, New Zealand
| | - Kathryn Wigley
- Dept. of Chemical & Process Engineering, University of Canterbury, Christchurch, New Zealand
| | - Kim Baronian
- Dept. of Chemical & Process Engineering, University of Canterbury, Christchurch, New Zealand
| | - Louise Weaver
- Institute of Environmental Science and Research Ltd., Christchurch, New Zealand
| | - Peter A Gostomski
- Dept. of Chemical & Process Engineering, University of Canterbury, Christchurch, New Zealand.
| |
Collapse
|
2
|
Paiva AC, Crucello J, de Aguiar Porto N, Hantao LW. Fundamentals of and recent advances in sorbent-based headspace extractions. Trends Analyt Chem 2021. [DOI: 10.1016/j.trac.2021.116252] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
|
3
|
Politano F, Sandoval AL, Uranga JG, Buján EI, Leadbeater NE. Using experimental and computational approaches to probe an unusual carbon-carbon bond cleavage observed in the synthesis of benzimidazole N-oxides. Org Biomol Chem 2021; 19:208-215. [PMID: 33179700 DOI: 10.1039/d0ob01797c] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Experimental and computational studies have been performed in order to investigate an unusual carbon-carbon bond cleavage that occurs in the preparation of certain benzimidazole N-oxides from anilines. The key factor determining the outcome of the reaction was found to be the substituents on the amine functionality of the aniline.
Collapse
Affiliation(s)
- Fabrizio Politano
- Department of Chemistry, University of Connecticut, 55 North Eagleville Road, Storrs, Connecticut 06269, USA.
| | | | | | | | | |
Collapse
|
4
|
Yu Y, Zhang K, Li Z, Ren C, Chen J, Lin YH, Liu J, Men Y. Microbial Cleavage of C-F Bonds in Two C 6 Per- and Polyfluorinated Compounds via Reductive Defluorination. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2020; 54:14393-14402. [PMID: 33121241 DOI: 10.1021/acs.est.0c04483] [Citation(s) in RCA: 69] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
The C-F bond is one of the strongest single bonds in nature. Although microbial reductive dehalogenation is well known for the other organohalides, no microbial reductive defluorination has been documented for perfluorinated compounds except for a single, nonreproducible study on trifluoroacetate. Here, we report on C-F bond cleavage in two C6 per- and polyfluorinated compounds via reductive defluorination by an organohalide-respiring microbial community. The reductive defluorination was demonstrated by the release of F- and the formation of the corresponding product when lactate was the electron donor, and the fluorinated compound was the sole electron acceptor. The major dechlorinating species in the seed culture, Dehalococcoides, were not responsible for the defluorination as no growth of Dehalococcoides or active expression of Dehalococcoides-reductive dehalogenases was observed. It suggests that minor phylogenetic groups in the community might be responsible for the reductive defluorination. These findings expand our fundamental knowledge of microbial reductive dehalogenation and warrant further studies on the enrichment, identification, and isolation of responsible microorganisms and enzymes. Given the wide use and emerging concerns of fluorinated organics (e.g., per- and polyfluoroalkyl substances), particularly the perfluorinated ones, the discovery of microbial defluorination under common anaerobic conditions may provide valuable insights into the environmental fate and potential bioremediation strategies of these notorious contaminants.
Collapse
Affiliation(s)
- Yaochun Yu
- Department of Chemical and Environmental Engineering, University of California, Riverside, California 92521, United States
- Department of Civil and Environmental Engineering, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, United States
| | - Kunyang Zhang
- Department of Civil and Environmental Engineering, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, United States
| | - Zhong Li
- Metabolomics Center, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, United States
| | - Changxu Ren
- Department of Chemical and Environmental Engineering, University of California, Riverside, California 92521, United States
| | - Jin Chen
- Environmental Toxicology Graduate Program, University of California, Riverside, California 92521, United States
| | - Ying-Hsuan Lin
- Environmental Toxicology Graduate Program, University of California, Riverside, California 92521, United States
- Department of Environmental Sciences, University of California, Riverside, California 92521, United States
| | - Jinyong Liu
- Department of Chemical and Environmental Engineering, University of California, Riverside, California 92521, United States
| | - Yujie Men
- Department of Chemical and Environmental Engineering, University of California, Riverside, California 92521, United States
- Department of Civil and Environmental Engineering, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, United States
| |
Collapse
|
5
|
Plaisance H, Mocho P, Desauziers V. Comparative analysis of formaldehyde and toluene sorption on indoor floorings and consequence on Indoor Air Quality. INDOOR AIR 2020; 30:1256-1267. [PMID: 32506531 DOI: 10.1111/ina.12704] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/27/2020] [Accepted: 05/25/2020] [Indexed: 05/21/2023]
Abstract
Indoor surfaces may be adsorptive sinks with the potential to change Indoor Air Quality. To estimate this effect, the sorption parameters of formaldehyde and toluene were assessed on five floorings by an experimental method using solid-phase microextraction in an airtight emission cell. Adsorption rate constants ranged from 0.003 to 0.075 m·h-1 , desorption rate constants from 0.019 to 0.51 h-1 , and the partition coefficient from 0.005 to 3.9 m, and these parameters vary greatly from one volatile organic compound/material couple to another indicating contrasted sorption behaviors. A rubber was identified as a sink of formaldehyde characterized by a very low desorption constant close to 0. For these sorbent floorings identified, the adsorption rates of formaldehyde are from 2 to 4 times higher than those of toluene. Two models were used to evaluate the sink effects of floorings on indoor pollutant concentrations in one room from different realistic conditions. The scenarios tested came to the conclusion that the formaldehyde sorption on one rubber (identified as a sink) has a maximum contribution from 15% to 21% for the conditions of low air exchange rate. For other floorings, the sorption has a minor contribution less than or equal to 5%, regardless of the air exchange rate.
Collapse
Affiliation(s)
- Herve Plaisance
- IPREM, IMT Mines Ales, Universite de Pau et des Pays de l'Adour, E2S UPPA, CNRS, Pau, France
| | - Pierre Mocho
- Universite de Pau et des Pays de l'Adour, E2S UPPA, Pau, France
| | - Valerie Desauziers
- IPREM, IMT Mines Ales, Universite de Pau et des Pays de l'Adour, E2S UPPA, CNRS, Pau, France
| |
Collapse
|
6
|
Nakamura J. Potential Doxorubicin-Mediated Dual-Targeting Chemotherapy in FANC/BRCA-Deficient Tumors via Modulation of Cellular Formaldehyde Concentration. Chem Res Toxicol 2020; 33:2659-2667. [PMID: 32876438 DOI: 10.1021/acs.chemrestox.0c00288] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Doxorubicin (DOX) is a widely used classical broad-spectrum anticancer drug. The major mechanism of DOX-mediated anticancer activity at clinically relevant concentrations is believed to be via DNA double-strand breaks due to topoisomerase IIα. However, other mechanisms by which DOX causes cytotoxicity have been proposed, including formaldehyde-dependent virtual interstrand cross-linking (ICL) formation. In this study, a method was established whereby cytotoxicity caused by virtual ICL derived from DOX is turned on and off using a cell culture system. Using this strategy, DOX-mediated cytotoxicity in Fanconi anemia group gene (FANC)/breast cancer susceptibility gene (BRCA)-deficient cells increased up to 70-fold compared to that in cells proficient in DNA repair pathways by increasing intracellular formaldehyde (FA) concentration. This approach also demonstrated that cytotoxicity introduced by DOX-mediated FA-dependent virtual ICL is completely independent of the toxicity induced by topoisomerase II inhibition at the cellular level. The potential of dual-targeting by DOX treatment was verified using an acid-specific FA donor. Overall, anticancer therapy targeting tumors deficient in the FANC/BRCA pathway may be possible by minimizing DOX-induced toxicity in normal cells.
Collapse
Affiliation(s)
- Jun Nakamura
- Laboratory of Laboratory Animal Science, Graduate School of Life and Environmental Biosciences, Osaka Prefecture University, Izumisano, Osaka 598-8531, Japan.,Department of Environmental Sciences and Engineering, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27516, United States
| |
Collapse
|
7
|
How improvements in monitoring and safety practices lowered airborne formaldehyde concentrations at an Italian university hospital: a summary of 20 years of experience. Arh Hig Rada Toksikol 2020; 71:178-189. [PMID: 33074166 PMCID: PMC7968499 DOI: 10.2478/aiht-2020-71-3406] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2020] [Accepted: 08/01/2020] [Indexed: 11/21/2022] Open
Abstract
The last two decades have been crucial for the assessment of airborne formaldehyde (FA) exposure in healthcare environments due to changes in limits and reference values, definition of carcinogenicity, and new monitoring methods. The aim of this study was to analyse twenty years (1999–2019) of experience in automatic, continuous airborne FA monitoring in the Pathology Laboratory and operating rooms at the Careggi University Hospital, Florence, Italy. These 20 years saw gradual improvements in FA monitoring of exposed employees considered at maximum risk, including improvements in analytical methods of detection and sampling strategies, which came with changes in procedures and workflow operations. In 2019, after the adoption of safe practices, including a closed-circuit system using pre-loaded containers and a vacuum sealing, 94 % of the total measurements (FA concentrations) were lower than 16 μg/m3, and only 6 % ranged from 21 to 75 μg/m3. In the studied work units, the ratio between area and personal readings ranged from 0.9 to 1.0, both for long and short-term sampling. Personal sampling was simplified with a new workstation, which integrated different monitoring systems into an innovative ergonomic armchair equipped with personal sampling devices. Area monitoring was also improved with a real-time, continuous photoacoustic instrument. Over these 20 years, FA exposure significantly dropped, which coincided with optimised histology workflow and implementation of safety practices. For high-throughput screening and cost savings we propose an innovative ergonomic armchair station which allows remote continuous monitoring.
Collapse
|
8
|
Mucci N, Dugheri S, Rapisarda V, Campagna M, Garzaro G, Farioli A, Cappelli G, Arcangeli G. Occupational exposure to airborne formaldehyde in hospital: setting an automatic sampling system, comparing different monitoring methods and applying them to assess exposure. LA MEDICINA DEL LAVORO 2019; 110:446-458. [PMID: 31846449 PMCID: PMC7809934 DOI: 10.23749/mdl.v110i6.8038] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/31/2018] [Revised: 05/07/2019] [Accepted: 10/07/2019] [Indexed: 12/16/2022]
Abstract
BACKGROUND In recent years, under-vacuum sealing (UVS) and containers with formalin encapsulated in the lid have been proposed for the reduction of occupational exposure to airborne formaldehyde (FA) in healthcare environments. OBJECTIVES We are presenting a study focused on the assessment of FA in hospitals: an automatic sampling system was set, different sampling devices were compared, and the concentration of FA was assessed, following its use in different scenarios. METHODS Three different devices for sampling/measuring FA were compared. They are based on: 1. silica gel cartridges impregnated with 2,4-dinitrophenylhydrazine (2,4-DNPH); 2. SPME® fiber using O-(2,3,4,5,6-pentafluorobenzyl)hydroxylamine; 3. direct reading commercial instrumentation. Three typical scenarios using FA were investigated: operating theatres where small biopsies are soaked into closed-circuit system 4% FA containers, secretariat of pathology laboratories during the registration of biopsies and pathology laboratories during the filling procedure by UVS and the slicing of biopsies. RESULTS The automatic sampling system allowed short-, long-, and in continuous-sampling time to measure airborne FA. Different sampling devices provided comparable results when tested to assess FA concentration ranging from 0.020-0.320 ppm in a test chamber, although the devices based on 2,4-DNPH were the best in terms of sensitivity and accuracy. The results of 246 samples showed that the FA concentration was less than 0.04 ppm in 91% of the measurements. CONCLUSIONS The automatic methods efficiently allow sampling and measurement of FA in hospital settings. When using safe practices, the concentration of FA is well below occupational limit values.
Collapse
Affiliation(s)
- Nicola Mucci
- Department of Experimental and Clinical Medicine, University of Florence, Florence, Italy.
| | | | | | | | | | | | | | | |
Collapse
|
9
|
Ghislain M, Costarramone N, Sotiropoulos JM, Pigot T, Van Den Berg R, Lacombe S, Le Bechec M. Direct analysis of aldehydes and carboxylic acids in the gas phase by negative ionization selected ion flow tube mass spectrometry: Quantification and modelling of ion-molecule reactions. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2019; 33:1623-1634. [PMID: 31216077 DOI: 10.1002/rcm.8504] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/16/2019] [Revised: 06/04/2019] [Accepted: 06/04/2019] [Indexed: 06/09/2023]
Abstract
RATIONALE The concentrations of aldehydes and volatile fatty acids have to be controlled because of their potential harmfulness in indoor air or relationship with the organoleptic properties of agri-food products. Although several specific analytical methods are currently used, the simultaneous analysis of these compounds in a complex matrix remains a challenge. The combination of positive and negative ionization selected ion flow tube mass spectrometry (SIFT-MS) allows the accurate, sensitive and high-frequency analysis of complex gas mixtures of these compounds. METHODS The ion-molecule reactions of negative precursor ions (OH- , O•- , O2 •- , NO2 - and NO3 - ) with five aldehydes and four carboxylic acids were investigated in order to provide product ions and rate constants for the quantification of these compounds by negative ion SIFT-MS. The results were compared with those obtained by conventional analysis methods and/or with already implemented SIFT-MS positive ionization methods. The modelling of hydroxide ion (OH- )/molecule reaction paths by ab-initio calculation allowed a better understanding of these gas-phase reactions. RESULTS Deprotonation systematically occurs by reaction between negative ions and aldehydes or acids, leading to the formation of [M - H]- primary ions. Ab-initio calculations demonstrated the α-CH deprotonation of aldehydes and the acidic proton abstraction for fatty acids. For aldehydes, the presence of water in the flow tube leads to the formation of hydrated ions, [M - H]- .H2 O. With the NO2 - precursor ion, a second reaction channel results in ion-molecule association with the formation of M.NO2 - ions. CONCLUSIONS Except for formaldehyde, all the studied compounds can be quantified by negative ion SIFT-MS with significant rate constants. In addition to positive ion SIFT-MS with H3 O+ , O2 + and NO+ precursor ions, negative ionization with O•- , O2 •- , OH- , NO2 - and NO3 - extends the range of analysis of aldehydes and carboxylic acids in air without a preparation or separation step. This methodology was illustrated by the simultaneous quantification in single-scan experiments of seven aldehydes and six carboxylic acids released by building materials.
Collapse
Affiliation(s)
- Mylène Ghislain
- CNRS/Univ. Pau & Pays Adour/E2S UPPA, IPREM, Institut des sciences analytiques et de Physicochimie pour l'environnement et les Matériaux, UMR5254, Hélioparc, 2 avenue Président Angot, 64053 PAU cedex 9, France
- Intersciences Nederlands, Tinstraat 16, 4823 AA, Breda, The Netherlands
| | | | - Jean-Marc Sotiropoulos
- CNRS/Univ. Pau & Pays Adour/E2S UPPA, IPREM, Institut des sciences analytiques et de Physicochimie pour l'environnement et les Matériaux, UMR5254, Hélioparc, 2 avenue Président Angot, 64053 PAU cedex 9, France
| | - Thierry Pigot
- CNRS/Univ. Pau & Pays Adour/E2S UPPA, IPREM, Institut des sciences analytiques et de Physicochimie pour l'environnement et les Matériaux, UMR5254, Hélioparc, 2 avenue Président Angot, 64053 PAU cedex 9, France
| | | | - Sylvie Lacombe
- CNRS/Univ. Pau & Pays Adour/E2S UPPA, IPREM, Institut des sciences analytiques et de Physicochimie pour l'environnement et les Matériaux, UMR5254, Hélioparc, 2 avenue Président Angot, 64053 PAU cedex 9, France
| | - Mickael Le Bechec
- CNRS/Univ. Pau & Pays Adour/E2S UPPA, IPREM, Institut des sciences analytiques et de Physicochimie pour l'environnement et les Matériaux, UMR5254, Hélioparc, 2 avenue Président Angot, 64053 PAU cedex 9, France
| |
Collapse
|
10
|
Recent Applications and Newly Developed Strategies of Solid-Phase Microextraction in Contaminant Analysis: Through the Environment to Humans. SEPARATIONS 2019. [DOI: 10.3390/separations6040054] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
The present review aims to describe the recent and most impactful applications in pollutant analysis using solid-phase microextraction (SPME) technology in environmental, food, and bio-clinical analysis. The covered papers were published in the last 5 years (2014–2019) thus providing the reader with information about the current state-of-the-art and the future potential directions of the research in pollutant monitoring using SPME. To this end, we revised the studies focused on the investigation of persistent organic pollutants (POPs), pesticides, and emerging pollutants (EPs) including personal care products (PPCPs), in different environmental, food, and bio-clinical matrices. We especially emphasized the role that SPME is having in contaminant surveys following the path that goes from the environment to humans passing through the food web. Besides, this review covers the last technological developments encompassing the use of novel extraction coatings (e.g., metal-organic frameworks, covalent organic frameworks, PDMS-overcoated fiber), geometries (e.g., Arrow-SPME, multiple monolithic fiber-SPME), approaches (e.g., vacuum and cold fiber SPME), and on-site devices. The applications of SPME hyphenated with ambient mass spectrometry have also been described.
Collapse
|
11
|
Vitola Pasetto L, Simon V, Richard R, Pic JS, Violleau F, Manero MH. Aldehydes gas ozonation monitoring: Interest of SIFT/MS versus GC/FID. CHEMOSPHERE 2019; 235:1107-1115. [PMID: 31561301 DOI: 10.1016/j.chemosphere.2019.06.186] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/14/2019] [Revised: 06/20/2019] [Accepted: 06/24/2019] [Indexed: 06/10/2023]
Abstract
Two analytical techniques - online Gas Chromatography coupled with Flame Ionization Detector (often used method for VOCs monitoring) versus Selected Ion Flow Tube coupled with Mass Spectrometry (a more recent technique based on direct mass spectrometry) - were compared in association to an ozone-based gas treatment. Selecting aldehydes as the representative VOCs, their concentrations were monitored during ozonation experiments by both techniques in parallel. Contradictory results were obtained in the presence of ozone. Aldehydes were up to 90% removed due to a reaction with ozone according to GC/FID analysis, whereas with SIFT/MS, aldehydes concentration remained at the same level during the experiments regardless of the ozone presence. In addition, it was demonstrated that the apparent aldehydes removal was affected by GC injector temperature, varying from 90% (when it was at 250 °C) to 60% (at 100 °C). Meanwhile, even when the ozonation reactor was heated to 100 °C, no aldehydes conversion was evidenced by SIFT/MS, suggesting that the GC injector temperature was not the only interference-causing parameter. The ozone-aldehyde reaction is probably catalyzed by some material of GC injector and/or column. An ozone-GC interference was therefore confirmed, making unsuitable the use of GC/FID with silicone stationary phase to monitor aldehydes in presence of high concentrations of ozone (at least 50 ppmv). On the other hand, SIFT/MS was validated as a reliable technique, which can be employed in order to measure VOCs concentrations in ozonation processes.
Collapse
Affiliation(s)
- Leticia Vitola Pasetto
- Laboratoire de Génie Chimique, Université de Toulouse, CNRS, INPT, UPS, Toulouse, France; Laboratoire de Chimie Agro-industrielle, LCA, Université de Toulouse, INRA, INPT-ENSIACET, Toulouse, France
| | - Valérie Simon
- Laboratoire de Chimie Agro-industrielle, LCA, Université de Toulouse, INRA, INPT-ENSIACET, Toulouse, France
| | - Romain Richard
- Laboratoire de Génie Chimique, Université de Toulouse, CNRS, INPT, UPS, Toulouse, France
| | - Jean-Stéphane Pic
- Laboratoire d'Ingénierie des Systèmes Biologiques et des Procédés, Université de Toulouse, CNRS, INRA, INSA, Toulouse, France
| | - Frédéric Violleau
- Laboratoire de Chimie Agro-industrielle, LCA, Université de Toulouse, INRA, INPT-ENSIACET, Toulouse, France.
| | - Marie-Hélène Manero
- Laboratoire de Génie Chimique, Université de Toulouse, CNRS, INPT, UPS, Toulouse, France
| |
Collapse
|
12
|
Dugheri S, Bonari A, Pompilio I, Colpo M, Mucci N, Arcangeli G. An Integrated Air Monitoring Approach for Assessment of Formaldehyde in the Workplace. Saf Health Work 2018; 9:479-485. [PMID: 30559999 PMCID: PMC6284158 DOI: 10.1016/j.shaw.2018.05.002] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2017] [Revised: 05/04/2018] [Accepted: 05/07/2018] [Indexed: 12/05/2022] Open
Abstract
The aim of this study is to validate an integrated air monitoring approach for assessing airborne formaldehyde (FA) in the workplace. An active sampling by silica gel impregnated with 2,4-dinitrophenylhydrazine, a passive solid phase microextraction technique using O-(2,3,4,5,6-pentafluorobenzyl)hydroxylamine as on-fiber derivatization reagent, an electrochemical direct-reading monitor, and an enzyme-based badge were evaluated and tested over a range of 0.020–5.12 ppm, using dynamically generated FA air concentrations. Simple linear regression analysis showed the four methods were suitable for evaluating airborne FA. Personal and area samplings in 12 anatomy pathology departments showed that the international occupational exposure limits in the GESTIS database were frequently exceeded. This monitoring approach would allow a fast, easy-to-use, and economical evaluation of both current work practices and eventual changes made to reduce FA vapor concentrations.
Collapse
Affiliation(s)
- Stefano Dugheri
- Laboratorio di Igiene e Tossicologia Industriale, Azienda Ospedaliero-Universitaria Careggi, Florence, Italy
- Corresponding author. Azienda Ospedaliero-Universitaria Careggi, Laboratorio di Igiene e Tossicologia Industriale, Largo P. Palagi 1, 50139 Florence, Italy.
| | - Alessandro Bonari
- Dipartimento di Medicina Sperimentale e Clinica, Università Degli Studi di Firenze, Florence, Italy
| | - Ilenia Pompilio
- Dipartimento di Medicina Sperimentale e Clinica, Università Degli Studi di Firenze, Florence, Italy
| | - Marco Colpo
- Dipartimento di Statistica, Informatica, Applicazioni, Università Degli Studi di Firenze, Florence, Italy
| | - Nicola Mucci
- Dipartimento di Medicina Sperimentale e Clinica, Università Degli Studi di Firenze, Florence, Italy
| | - Giulio Arcangeli
- Dipartimento di Medicina Sperimentale e Clinica, Università Degli Studi di Firenze, Florence, Italy
| |
Collapse
|
13
|
Rieber W, Beck W. Syntheses of Transition Metal Complexes of Pentafluorophenylhydrazine. Z Anorg Allg Chem 2018. [DOI: 10.1002/zaac.201800010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Wolfram Rieber
- Department Chemie; Ludwig-Maximilians-Universität München; Butenandtstr. 5-13 81377 München Germany
| | - Wolfgang Beck
- Department Chemie; Ludwig-Maximilians-Universität München; Butenandtstr. 5-13 81377 München Germany
| |
Collapse
|
14
|
Rousová J, Chintapalli MR, Lindahl A, Casey J, Kubátová A. Simultaneous determination of trace concentrations of aldehydes and carboxylic acids in particulate matter. J Chromatogr A 2018; 1544:49-61. [DOI: 10.1016/j.chroma.2018.02.026] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2017] [Revised: 02/06/2018] [Accepted: 02/14/2018] [Indexed: 01/26/2023]
|
15
|
Under glass weathering of hemp fibers reinforced polypropylene biocomposites: Impact of Volatile Organic Compounds emissions on indoor air quality. Polym Degrad Stab 2018. [DOI: 10.1016/j.polymdegradstab.2018.01.020] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
|
16
|
Plaisance H, Mocho P, Sauvat N, Vignau-Laulhere J, Raulin K, Desauziers V. Using the chemical mass balance model to estimate VOC source contributions in newly built timber frame houses: a case study. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2017; 24:24156-24166. [PMID: 28884255 DOI: 10.1007/s11356-017-0025-z] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/09/2017] [Accepted: 08/23/2017] [Indexed: 06/07/2023]
Abstract
Basing on the material emission data obtained in a test chamber, chemical mass balance (CMB) was used to assess the source apportionment of volatile organic compound (VOC) concentrations in three newly built timber frame houses. CMB has been proven to be able to discriminate the source contributions for two contrasted environmental conditions (with and without ventilation). The shutdown of the ventilation system caused an increase in the VOC concentrations due to the increased contribution of indoor surface materials like the door material and furniture explaining together over 65% of total VOCs. While the increase in formaldehyde concentration is mainly due to furniture (contribution of 70%), the increase in α-pinene concentration is almost exclusively attributable to the emission of door material (up to 84%). The apportionment of VOC source contributions appears as highly dependent on the position of source materials in the building (surface materials or internal materials) and the ventilation conditions explaining that the concentrations of compounds after the shutdown of ventilation system do not increase in equivalent proportion. Knowledge of indoor sources and its contributions in real conditions may help in the selection of materials and in the improvement of construction operations to reduce the indoor air pollution.
Collapse
Affiliation(s)
- Herve Plaisance
- Pôle RIME-C2MA, Ecole des Mines d'Alès, Hélioparc, 2 Avenue Pierre Angot, 64053, Pau, Cedex 9, France.
| | - Pierre Mocho
- Laboratoire Thermique Energétique et Procédés, Université de Pau et des Pays de l'Adour, BP 7511-64053, Pau, France
| | - Nicolas Sauvat
- GEMH, Université de Limoges, 30 Boulevard du Puy Nègre, 19300, Egletons, France
| | - Jane Vignau-Laulhere
- Pôle RIME-C2MA, Ecole des Mines d'Alès, Hélioparc, 2 Avenue Pierre Angot, 64053, Pau, Cedex 9, France
| | | | - Valerie Desauziers
- Pôle RIME-C2MA, Ecole des Mines d'Alès, Hélioparc, 2 Avenue Pierre Angot, 64053, Pau, Cedex 9, France
| |
Collapse
|
17
|
Oxidative damage and impairment of protein quality control systems in keratinocytes exposed to a volatile organic compounds cocktail. Sci Rep 2017; 7:10707. [PMID: 28878258 PMCID: PMC5587662 DOI: 10.1038/s41598-017-11088-1] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2017] [Accepted: 08/14/2017] [Indexed: 12/19/2022] Open
Abstract
Compelling evidence suggests that volatile organic compounds (VOCs) have potentially harmful effects to the skin. However, knowledge about cellular signaling events and toxicity subsequent to VOC exposure to human skin cells is still poorly documented. The aim of this study was to focus on the interaction between 5 different VOCs (hexane, toluene, acetaldehyde, formaldehyde and acetone) at doses mimicking chronic low level environmental exposure and the effect on human keratinocytes to get better insight into VOC-cell interactions. We provide evidence that the proteasome, a major intracellular proteolytic system which is involved in a broad array of processes such as cell cycle, apoptosis, transcription, DNA repair, protein quality control and antigen presentation, is a VOC target. Proteasome inactivation after VOC exposure is accompanied by apoptosis, DNA damage and protein oxidation. Lon protease, which degrades oxidized, dysfunctional, and misfolded proteins in the mitochondria is also a VOC target. Using human skin explants we found that VOCs prevent cell proliferation and also inhibit proteasome activity in vivo. Taken together, our findings provide insight into potential mechanisms of VOC-induced proteasome inactivation and the cellular consequences of these events.
Collapse
|
18
|
Gross A, Mocho P, Plaisance H, Cantau C, Kinadjian N, Yrieix C, Desauziers V. Assessment of VOCs material/air exchanges of building products using the DOSEC®-SPME method. ACTA ACUST UNITED AC 2017. [DOI: 10.1016/j.egypro.2017.07.318] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
|
19
|
Plaisance H, Vignau-Laulhere J, Mocho P, Sauvat N, Raulin K, Desauziers V. Volatile organic compounds concentrations during the construction process in newly-built timber-frame houses: source identification and emission kinetics. ENVIRONMENTAL SCIENCE. PROCESSES & IMPACTS 2017; 19:696-710. [PMID: 28387778 DOI: 10.1039/c7em00047b] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Building and furniture materials are known to be major sources of volatile organic compounds (VOCs) indoors. During the construction process, an introduced material can have a more or less long-term impact on the indoor air quality according to the building characteristics. In this study, field measurements were carried out at six construction stages in three energy-efficient timber-frame houses. Data analysis focused on the ten most abundant compounds found among an initial list of fifteen target VOCs, namely formaldehyde, acetaldehyde, hexanal, toluene, m/p-xylenes, ethylbenzene, styrene, α-pinene, 3-carene and d-limonene. The chemical compositions and concentration variation patterns were recorded. The results showed a high pollution count, with m/p-xylenes and ethylbenzene concentrations ranging from 1900 to 5100 μg m-3 occurring at the time of the structural work (representing more than 88% of the sum of the target VOCs). Emission tests done on a large number of materials used in the construction revealed that this pollution is due to the emissions from the polyurethane adhesive mastic used as a sealing material. The emission kinetics of polyurethane adhesive mastic was assessed alone and also within a material assembly reconstituting a room wall. The results showed that the superposition of materials led to a slowing down of the VOC emission process from polyurethane adhesive mastic, which explains the concentration decays recorded in houses during the construction process. At the final construction stage, the concentration levels were low for all compounds (the sums of the target VOCs were between 18 and 32 μg m-3), with the aldehydes (formaldehyde, acetaldehyde and hexanal) now becoming the major fraction in the chemical composition in the last stages of construction (representing 50-70% of the sum of the target VOCs). This is in agreement with the fact that the sources of aldehydes are the most numerous among the materials and have rather slow emission kinetics.
Collapse
Affiliation(s)
- H Plaisance
- Pôle RIME-C2MA, Ecole des Mines d'Alès, Hélioparc, 2 Avenue Pierre Angot, 64053 Pau Cedex 9, France.
| | | | | | | | | | | |
Collapse
|
20
|
Metal-organic frameworks as superior media for thermal desorption-gas chromatography application: A critical assessment of MOF-5 for the quantitation of airborne formaldehyde. Microchem J 2017. [DOI: 10.1016/j.microc.2017.01.032] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
|
21
|
Costarramone N, Cantau C, Desauziers V, Pécheyran C, Pigot T, Lacombe S. Photocatalytic air purifiers for indoor air: European standard and pilot room experiments. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2017; 24:12538-12546. [PMID: 27628923 DOI: 10.1007/s11356-016-7607-z] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/08/2016] [Accepted: 09/05/2016] [Indexed: 06/06/2023]
Abstract
At the European level (CEN/TC386), some efforts are currently devoted to new standards for comparing the efficiency of commercial photocatalytic material/devices in various application fields. Concerning prototype or commercial indoor photocatalytic air purifiers designed for volatile organic compounds (VOC) abatement, the methodology is based on a laboratory airtight chamber. The photocatalytic function is demonstrated by the mineralization of a mixture of five VOCs. Experimental data were obtained for four selected commercial devices and three commercial materials: drop of VOC concentration, but also identification of secondary species (with special attention to formaldehyde), mineralization rates, and Clean Air Delivery Rate (CADR). With two efficient air purifiers, these laboratory experiments were compared to the results in two experimental rooms (35-40 m3) where air pollution was introduced through wooden floor and furniture. The systems' ageing was also studied. The safety of the commercial products was also assessed by the determination of nanoparticle release. Standardized tests are useful to rank photocatalytic air purifiers and passive materials and to discard inefficient ones. A good correlation between the standard experiments and the experimental room experiments was found, even if in the latter case, the concentration of lower weight VOCs drops less quickly than that of heavier VOCs.
Collapse
Affiliation(s)
- N Costarramone
- UT2A, Hélioparc, 2 Avenue du Président Angot, BP 1153, 64013, Pau cedex, France
- IPREM, UMR CNRS 5254, Université de Pau et Pays de l'Adour Hélioparc, 2 Av. Pdt Angot, BP 1153, 64013, Pau cedex, France
| | - C Cantau
- NOBATEK, 67 rue de Mirambeau, 64600, Anglet, France
| | - V Desauziers
- C2MA Ecole des Mines d'Alès, Hélioparc, 2 Av. Pdt Angot, BP 1153, 64013, Pau cedex, France
| | - C Pécheyran
- IPREM, UMR CNRS 5254, Université de Pau et Pays de l'Adour Hélioparc, 2 Av. Pdt Angot, BP 1153, 64013, Pau cedex, France
| | - T Pigot
- IPREM, UMR CNRS 5254, Université de Pau et Pays de l'Adour Hélioparc, 2 Av. Pdt Angot, BP 1153, 64013, Pau cedex, France
| | - S Lacombe
- IPREM, UMR CNRS 5254, Université de Pau et Pays de l'Adour Hélioparc, 2 Av. Pdt Angot, BP 1153, 64013, Pau cedex, France.
| |
Collapse
|
22
|
Zhao W, Zhang Q, Lu B, Sun S, Zhang S, Zhang J. Rapid Determination of Six Low Molecular Carbonyl Compounds in Tobacco Smoke by the APCI-MS/MS Coupled to Data Mining. JOURNAL OF ANALYTICAL METHODS IN CHEMISTRY 2017; 2017:8260860. [PMID: 28512594 PMCID: PMC5415865 DOI: 10.1155/2017/8260860] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/31/2016] [Revised: 01/14/2017] [Accepted: 02/15/2017] [Indexed: 06/07/2023]
Abstract
A simple method was established for the rapid determination of low molecular carbonyl compounds by the combination of atmospheric pressure chemical ionization tandem mass spectrometry (APCI-MS/MS) and data mining. The ionization was carried out in positive mode, and six low molecular carbonyl compounds of acrolein, acetone, propionaldehyde, crotonaldehyde, butanone, and butyraldehyde were analyzed by both full scan mode and daughter scan mode. To overcome the quantitative difficulties from isomer of acetone/propionaldehyde and butanone/butyraldehyde, the quantitation procedure was performed with the characteristic ion of [CH3O]+ under CID energy of 5 and 15 eV. Subsequently, the established method was successfully applied to analysis of six low molecular carbonyl compounds in tobacco smoke with analytical period less than four minutes. The contents of acrolein, acetone, propionaldehyde, crotonaldehyde, butanone, and butyraldehyde for a cigarette were about 63 ± 5.8, 325 ± 82, 55 ± 9.7, 11 ± 1.4, 67 ± 5.9, and 12 ± 1.8 μg/cig, respectively. The experimental results indicated that the established method had the potential application in rapid determination of low molecular carbonyl compounds.
Collapse
Affiliation(s)
- Wuduo Zhao
- Zhengzhou Tobacco Research Institute, China National Tobacco Corporation, Zhengzhou 450001, China
- College of Chemistry and Molecular Engineering, Zhengzhou University, Zhengzhou 450001, China
| | - Qidong Zhang
- Zhengzhou Tobacco Research Institute, China National Tobacco Corporation, Zhengzhou 450001, China
| | - Binbin Lu
- Zhengzhou Tobacco Research Institute, China National Tobacco Corporation, Zhengzhou 450001, China
| | - Shihao Sun
- Zhengzhou Tobacco Research Institute, China National Tobacco Corporation, Zhengzhou 450001, China
| | - Shusheng Zhang
- College of Chemistry and Molecular Engineering, Zhengzhou University, Zhengzhou 450001, China
| | - Jianxun Zhang
- Zhengzhou Tobacco Research Institute, China National Tobacco Corporation, Zhengzhou 450001, China
| |
Collapse
|
23
|
Poole JJ, Grandy JJ, Gómez-Ríos GA, Gionfriddo E, Pawliszyn J. Solid Phase Microextraction On-Fiber Derivatization Using a Stable, Portable, and Reusable Pentafluorophenyl Hydrazine Standard Gas Generating Vial. Anal Chem 2016; 88:6859-66. [DOI: 10.1021/acs.analchem.6b01449] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Affiliation(s)
- Justen J. Poole
- Department
of Chemistry, University of Waterloo, Waterloo, Ontario N2L 3G1, Canada
| | - Jonathan J. Grandy
- Department
of Chemistry, University of Waterloo, Waterloo, Ontario N2L 3G1, Canada
| | - German A. Gómez-Ríos
- Department
of Chemistry, University of Waterloo, Waterloo, Ontario N2L 3G1, Canada
| | - Emanuela Gionfriddo
- Department
of Chemistry, University of Waterloo, Waterloo, Ontario N2L 3G1, Canada
| | - Janusz Pawliszyn
- Department
of Chemistry, University of Waterloo, Waterloo, Ontario N2L 3G1, Canada
| |
Collapse
|
24
|
Vignau-Laulhere J, Mocho P, Plaisance H, Raulin K, Desauziers V. Assessment of diffusion parameters of new passive samplers using optical chemical sensor for on-site measuring formaldehyde in indoor air: experimental and numerical studies. Anal Bioanal Chem 2016; 408:2147-57. [DOI: 10.1007/s00216-016-9317-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2015] [Revised: 12/16/2015] [Accepted: 01/07/2016] [Indexed: 10/22/2022]
|
25
|
Recent Developments and Applications of Solid Phase Microextraction (SPME) in Food and Environmental Analysis—A Review. CHROMATOGRAPHY 2015. [DOI: 10.3390/chromatography2030293] [Citation(s) in RCA: 128] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
|
26
|
Zhao J, Wang G, Cao T, Guo Z. Development of a Novel Derivate Assay for Formaldehyde Determination by HPLC in Beer Samples. FOOD ANAL METHOD 2015. [DOI: 10.1007/s12161-015-0183-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
|
27
|
|
28
|
A novel miniaturized extraction capillary for determining gaseous formaldehyde by high-performance liquid chromatography. Anal Bioanal Chem 2014; 407:899-905. [DOI: 10.1007/s00216-014-8144-6] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2014] [Revised: 08/26/2014] [Accepted: 08/28/2014] [Indexed: 10/24/2022]
|
29
|
Bardet G, Achard S, Loret T, Desauziers V, Momas I, Seta N. A model of human nasal epithelial cells adapted for direct and repeated exposure to airborne pollutants. Toxicol Lett 2014; 229:144-9. [PMID: 24960057 DOI: 10.1016/j.toxlet.2014.05.023] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2014] [Revised: 05/04/2014] [Accepted: 05/27/2014] [Indexed: 12/28/2022]
Abstract
Airway epithelium lining the nasal cavity plays a pivotal role in respiratory tract defense and protection mechanisms. Air pollution induces alterations linked to airway diseases such as asthma. Only very few in vitro studies to date have succeeded in reproducing physiological conditions relevant to cellular type and chronic atmospheric pollution exposure. We therefore, set up an in vitro model of human Airway Epithelial Cells of Nasal origin (hAECN) close to real human cell functionality, specifically adapted to study the biological effects of exposure to indoor gaseous pollution at the environmental level. hAECN were exposed under air-liquid interface, one, two, or three-times at 24 h intervals for 1 h, to air or formaldehyde (200 μg/m(3)), an indoor air gaseous pollutant. All experiments were ended at day 4, when both cellular viability and cytokine production were assessed. Optimal adherence and confluence of cells were obtained 96 h after cell seeding onto collagen IV-precoated insert. Direct and repeated exposure to formaldehyde did not produce any cellular damage or IL-6 production change, although weak lower IL-8 production was observed only after the third exposure. Our model is significantly better than previous ones due to cell type and the repeated exposure protocol.
Collapse
Affiliation(s)
- Gaëlle Bardet
- Université Paris Descartes, EA 4064, Laboratoire de Santé Publique et Environnement, 4, Avenue de l'Observatoire, 75006 Paris, France; Agence de l'Environnement et de la Maîtrise de l'Energie, Angers, France.
| | - Sophie Achard
- Université Paris Descartes, EA 4064, Laboratoire de Santé Publique et Environnement, 4, Avenue de l'Observatoire, 75006 Paris, France.
| | - Thomas Loret
- Université Paris Descartes, EA 4064, Laboratoire de Santé Publique et Environnement, 4, Avenue de l'Observatoire, 75006 Paris, France.
| | - Valérie Desauziers
- Centre des Matériaux des Mines d'Alès, Ecole des Mines d'Alès, Pau, France.
| | - Isabelle Momas
- Université Paris Descartes, EA 4064, Laboratoire de Santé Publique et Environnement, 4, Avenue de l'Observatoire, 75006 Paris, France.
| | - Nathalie Seta
- Université Paris Descartes, EA 4064, Laboratoire de Santé Publique et Environnement, 4, Avenue de l'Observatoire, 75006 Paris, France; AP-HP, Hôpital Bichat, Biochimie, Paris, France.
| |
Collapse
|