1
|
Jaber N, Billet S. How to use an in vitro approach to characterize the toxicity of airborne compounds. Toxicol In Vitro 2024; 94:105718. [PMID: 37871865 DOI: 10.1016/j.tiv.2023.105718] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2023] [Revised: 09/13/2023] [Accepted: 09/21/2023] [Indexed: 10/25/2023]
Abstract
As part of the development of new approach methodologies (NAMs), numerous in vitro methods are being developed to characterize the potential toxicity of inhalable xenobiotics (gases, volatile organic compounds, polycyclic aromatic hydrocarbons, particulate matter, nanoparticles). However, the materials and methods employed are extremely diverse, and no single method is currently in use. Method standardization and validation would raise trust in the results and enable them to be compared. This four-part review lists and compares biological models and exposure methodologies before describing measurable biomarkers of exposure or effect. The first section emphasizes the importance of developing alternative methods to reduce, if not replace, animal testing (3R principle). The biological models presented are mostly to cultures of epithelial cells from the respiratory system, as the lungs are the first organ to come into contact with air pollutants. Monocultures or cocultures of primary cells or cell lines, as well as 3D organotypic cultures such as organoids, spheroids and reconstituted tissues, but also the organ(s) model on a chip are examples. The exposure methods for these biological models applicable to airborne compounds are submerged, intermittent, continuous either static or dynamic. Finally, within the restrictions of these models (i.e. relative tiny quantities, adhering cells), the mechanisms of toxicity and the phenotypic markers most commonly examined in models exposed at the air-liquid interface (ALI) are outlined.
Collapse
Affiliation(s)
- Nour Jaber
- UR4492, Unité de Chimie Environnementale et Interactions sur le Vivant, Université du Littoral Côte d'Opale, Dunkerque, France
| | - Sylvain Billet
- UR4492, Unité de Chimie Environnementale et Interactions sur le Vivant, Université du Littoral Côte d'Opale, Dunkerque, France.
| |
Collapse
|
2
|
Zhang J, Zhou X, Ma J, Ren L, Liu L. Dimethyl sulfate poisoning in China: a fatal case and a 45-year retrospective study. Forensic Sci Med Pathol 2023:10.1007/s12024-023-00740-0. [PMID: 37924417 DOI: 10.1007/s12024-023-00740-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/16/2023] [Indexed: 11/06/2023]
Abstract
Dimethyl sulfate (DMS) is a highly toxic chemical that appears innocuous and is commonly used as a methylating agent in industry. It can be readily absorbed leading to poisoning or death through the skin or mucous membranes of the respiratory tract in the process of production or transportation. Although there are some articles on treatment for DMS poisoning, reports of death resulting from acute fatal DMS poisoning are very rare. Here, we present a case of a 50-year-old Chinese man who died accidentally from DMS poisoning after he broke a plastic storage tank full of DMS during transportation. The patient complained of eye irritation. In addition, the corrosive damage could be seen in his corneas and skin. The autopsy revealed erosions and ulcers in the respiratory tract, as well as massive congestion, necrosis, edema, and pseudomembrane formation on the mucous layer of the trachea and main bronchi. Histopathological examination confirmed extensive pulmonary edema, multifocal hemorrhages, whole-cell swelling in the brain, as well as disintegration of the neuronal cell. We inferred that DMS poisoning caused the symptoms resulting from the production of methanol and sulfate through hydrolysis, including respiratory toxicity and neurotoxicity, and these symptoms had temporal continuity. Toxicological analysis revealed no DMS or methanol, but formic acid was detected in the brain, both qualitatively and quantitatively. In this report, we also present a retrospective study of 8 similar cases of DMS poisoning in literature in China, including some clinical data and autopsy information.
Collapse
Affiliation(s)
- Jie Zhang
- Department of Forensic Medicine, Tongji Medical College, Huazhong University of Science and Technology, No.13, Hangkong Road, Qiaokou District, Wuhan, Hubei Province, China
| | - Xiaowei Zhou
- Hubei Chongxin Judicial Expertise Center, Wuhan, Hubei, China
| | - Jinghong Ma
- Hubei Chongxin Judicial Expertise Center, Wuhan, Hubei, China
| | - Liang Ren
- Department of Forensic Medicine, Tongji Medical College, Huazhong University of Science and Technology, No.13, Hangkong Road, Qiaokou District, Wuhan, Hubei Province, China.
| | - Liang Liu
- Department of Forensic Medicine, Tongji Medical College, Huazhong University of Science and Technology, No.13, Hangkong Road, Qiaokou District, Wuhan, Hubei Province, China.
| |
Collapse
|
3
|
Singh AV, Bansod G, Mahajan M, Dietrich P, Singh SP, Rav K, Thissen A, Bharde AM, Rothenstein D, Kulkarni S, Bill J. Digital Transformation in Toxicology: Improving Communication and Efficiency in Risk Assessment. ACS OMEGA 2023; 8:21377-21390. [PMID: 37360489 PMCID: PMC10286258 DOI: 10.1021/acsomega.3c00596] [Citation(s) in RCA: 27] [Impact Index Per Article: 27.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/29/2023] [Accepted: 05/09/2023] [Indexed: 06/28/2023]
Abstract
Toxicology is undergoing a digital revolution, with mobile apps, sensors, artificial intelligence (AI), and machine learning enabling better record-keeping, data analysis, and risk assessment. Additionally, computational toxicology and digital risk assessment have led to more accurate predictions of chemical hazards, reducing the burden of laboratory studies. Blockchain technology is emerging as a promising approach to increase transparency, particularly in the management and processing of genomic data related with food safety. Robotics, smart agriculture, and smart food and feedstock offer new opportunities for collecting, analyzing, and evaluating data, while wearable devices can predict toxicity and monitor health-related issues. The review article focuses on the potential of digital technologies to improve risk assessment and public health in the field of toxicology. By examining key topics such as blockchain technology, smoking toxicology, wearable sensors, and food security, this article provides an overview of how digitalization is influencing toxicology. As well as highlighting future directions for research, this article demonstrates how emerging technologies can enhance risk assessment communication and efficiency. The integration of digital technologies has revolutionized toxicology and has great potential for improving risk assessment and promoting public health.
Collapse
Affiliation(s)
- Ajay Vikram Singh
- Department
of Chemical and Product Safety, German Federal
Institute for Risk Assessment (BfR), Max-Dohrn-Straße 8-10, 10589 Berlin, Germany
| | - Girija Bansod
- Rajiv
Gandhi Institute of IT and Biotechnology, Bharati Vidyapeeth (deemed to be) University, Pune 411045, India
| | - Mihir Mahajan
- Department
of Informatics, Technical University of
Munich, 85758 Garching, Germany
| | - Paul Dietrich
- SPECS
Surface Nano Analysis GmbH, Voltastrasse 5, 13355 Berlin, Germany
| | - Shivam Pratap Singh
- School
of Computer and Mathematical Sciences, University
of Greenwich, London SE10 9LS, U.K.
| | - Kranti Rav
- Delta
Biopharmaceutical, Andhra Pradesh 524126, India
| | - Andreas Thissen
- SPECS
Surface Nano Analysis GmbH, Voltastrasse 5, 13355 Berlin, Germany
| | - Aadya Mandar Bharde
- Guru
Nanak Khalsa College of Arts Science and Commerce, Mumbai 400 037, India
| | - Dirk Rothenstein
- Institute
for Materials Science, Department of Bioinspired Materials, University of Stuttgart, 70569 Stuttgart, Germany
| | - Shilpa Kulkarni
- Seeta
Nursing Home, Shivaji
Nagar, Nashik, Maharashtra 422002, India
| | - Joachim Bill
- Institute
for Materials Science, Department of Bioinspired Materials, University of Stuttgart, 70569 Stuttgart, Germany
| |
Collapse
|
4
|
Carberry CK, Rager JE. The impact of environmental contaminants on extracellular vesicles and their key molecular regulators: A literature and database-driven review. ENVIRONMENTAL AND MOLECULAR MUTAGENESIS 2023; 64:50-66. [PMID: 36502378 PMCID: PMC10798145 DOI: 10.1002/em.22522] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/05/2022] [Revised: 12/01/2022] [Accepted: 12/06/2022] [Indexed: 06/17/2023]
Abstract
Exposure to environmental chemicals is now well recognized as a significant factor contributing to the global burden of disease; however, there remain critical gaps in understanding the types of biological mechanisms that link environmental chemicals to adverse health outcomes. One type of mechanism that remains understudied involves extracellular vesicles (EVs), representing small cell-derived particles capable of carrying molecular signals such as RNAs, miRNAs, proteins, lipids, and chemicals through biological fluids and imparting beneficial, neutral, or negative effects on target cells. In fact, evidence is just now starting to grow that supports the role of EVs in various disease etiologies. This review aims to (1) Provide a landscape of the current understanding of the functional relationship between EVs and environmental chemicals; (2) Summarize current knowledge of EV regulatory processes including production, packaging, and release; and (3) Conduct a database-driven analysis of known chemical-gene interactions to predict and prioritize environmentally relevant chemicals that may impact EV regulatory genes and thus EV regulatory processes. This approach to predicting environmentally relevant chemicals that may alter EVs provides a novel method for evidence-based hypothesis generation for future studies evaluating the link between environmental exposures and EVs.
Collapse
Affiliation(s)
- Celeste K. Carberry
- Department of Environmental Sciences and Engineering, Gillings School of Global Public Health, The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
- The Institute for Environmental Health Solutions, Gillings School of Global Public Health, The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Julia E. Rager
- Department of Environmental Sciences and Engineering, Gillings School of Global Public Health, The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
- The Institute for Environmental Health Solutions, Gillings School of Global Public Health, The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
- Curriculum in Toxicology and Environmental Medicine, School of Medicine, University of North Carolina, Chapel Hill, North Carolina, USA
| |
Collapse
|
5
|
Acute cytotoxicity test of PM 2.5, NNK and BPDE in human normal bronchial epithelial cells: A comparison of a co-culture model containing macrophages and a mono-culture model. Toxicol In Vitro 2022; 85:105480. [PMID: 36152786 DOI: 10.1016/j.tiv.2022.105480] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2022] [Revised: 09/09/2022] [Accepted: 09/18/2022] [Indexed: 11/23/2022]
Abstract
BACKGROUND Based on extensive research on cytotoxicity of exogenous compounds in vitro, it is essential to develop a cell model that better mimics environment in vivo to explore cytotoxic mechanisms of exogenous compounds. METHODS A co-culture system was established using a transwell system with Beas-2B and U937 cells. Cells were treated with fine particulate matter (PM2.5; 25, 50 and 100 μg/mL), nicotine-derived nitrosamine ketone (NNK; 50, 100 and 200 μg/mL) and benzo(a)pyrene diol epoxide (BPDE; 0.5, 2 and 8 μM) for 24 h. Cell proliferation, apoptosis and cell cycle, DNA damage were detected by CCK-8 and EdU, flow cytometry, and comet assay, respectively. Differentially expressed transcript and cytokine concentrations were determined by transcriptome sequencing and Cytokine Array, respectively. RESULTS Compared with mono-culture, cell proliferation increased, apoptosis decreased, and DNA damage decreased in a dose-response relationship in co-culture. Gene expression profile was significantly different in co-culture, with significantly increased expression levels of 48 cytokines in co-culture. CONCLUSION Cytotoxic damage to Beas-2B cells induced by exogenous carcinogens, including PM2.5, NNK and BPDE, was significantly reduced in a co-culture system compared with a mono-culture system. The mechanism may be related to changes in expression of cytokines, such as LIF, and activation of related pathways, such as TNF signaling pathway. Cytotoxic damage to Beas-2B induced by PM2.5, NNK and BPDE, was significantly reduced in co-culture. The mechanism may be related to changes in expression of cytokines and activation of related pathways. These findings provide new insights into cytotoxicity and experimental basis for safety evaluations of exogenous carcinogens.
Collapse
|
6
|
Metz JK, Hittinger M, Lehr CM. In vitro tools for orally inhaled drug products-state of the art for their application in pharmaceutical research and industry and regulatory challenges. IN VITRO MODELS 2021; 1:29-40. [PMID: 38624975 PMCID: PMC8688684 DOI: 10.1007/s44164-021-00003-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/02/2021] [Revised: 09/02/2021] [Accepted: 09/26/2021] [Indexed: 11/25/2022]
Abstract
The drug development process is a lengthy and expensive challenge for all involved players. Experience with the COVID-19 pandemic underlines the need for a rapid and effective approval for treatment options. As essential prerequisites for successful drug approval, a combination of high-quality studies and reliable research must be included. To this day, mainly in vivo data are requested and collected for assessing safety and efficacy and are therefore decisive for the pre-clinical evaluation of the respective drug. This review aims to summarize the current state of the art for safety and efficacy studies in pharmaceutical research and industry to address the relevant regulatory challenges and to provide an outlook on implementing more in vitro methods as alternative to animal testing. While the public demand for alternative methods is becoming louder, first examples have meanwhile found acceptance in relevant guidelines, e.g. the OECD guidelines for skin sensitizer. Besides ethically driven developments, also the rather low throughput and relatively high costs of animal experiments are forcing the industry towards the implementation of alternative methods. In this context, the development of orally inhaled drug products is particularly challenging due to the complexity of the lung as biological barrier and route of administration. The replacement of animal experiments with focus on the lungs requires special designed tools to achieve predictive data. New in vitro test systems of increasing complexity are presented in this review. Limits and advantages are discussed to provide some perspective for a future in vitro testing strategy for orally inhaled drug products. Graphical abstract
Collapse
Affiliation(s)
- Julia Katharina Metz
- Department of Drug Delivery, PharmBioTec Research & Development GmbH, 66123 Saarbrücken, Germany
- Department of Pharmacy, Saarland University, 66123 Saarbrücken, Germany
- Helmholtz Institute for Pharmaceutical Research Saarland (HIPS), Helmholtz Center for Infection Research (HZI), 66123 Saarbrücken, Germany
| | - Marius Hittinger
- Department of Drug Delivery, PharmBioTec Research & Development GmbH, 66123 Saarbrücken, Germany
| | - Claus-Michael Lehr
- Department of Pharmacy, Saarland University, 66123 Saarbrücken, Germany
- Helmholtz Institute for Pharmaceutical Research Saarland (HIPS), Helmholtz Center for Infection Research (HZI), 66123 Saarbrücken, Germany
| |
Collapse
|
7
|
Karkossa I, Bannuscher A, Hellack B, Wohlleben W, Laloy J, Stan MS, Dinischiotu A, Wiemann M, Luch A, Haase A, von Bergen M, Schubert K. Nanomaterials induce different levels of oxidative stress, depending on the used model system: Comparison of in vitro and in vivo effects. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 801:149538. [PMID: 34428663 DOI: 10.1016/j.scitotenv.2021.149538] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/04/2021] [Revised: 08/03/2021] [Accepted: 08/04/2021] [Indexed: 06/13/2023]
Abstract
The immense diversity and constant development of nanomaterials (NMs) increase the need for a facilitated risk assessment, which requires knowledge of the modes of action (MoAs) of NMs. This necessitates a comprehensive data basis, which can be obtained using omics. Furthermore, the establishment of suitable in vitro test systems is essential to follow the 3R concept and to cope with the high number of NMs. In the present study, we aimed to compare NM effects in vitro and in vivo using a multi-omics approach. We applied an integrated data analysis strategy based on proteomics and metabolomics to four silica NMs and one titanium dioxide-based NM. For the in vitro investigations, rat alveolar epithelial cells (RLE-6TN) and rat alveolar macrophages (NR8383) were treated with different doses of NMs, and the results were compared with the effects on rat lungs after short-term inhalations and instillations. Since reactive oxygen species (ROS) production has been described as a critical biological effect of NMs, we focused on different levels of oxidative stress. Thus, we found opposite changes in proteins and metabolites related to the production of reduced glutathione in alveolar epithelial cells and alveolar macrophages, demonstrating that the MoAs of NMs depend on the model system used. Interestingly, in vivo, pathways related to inflammation were more affected than oxidative stress responses. Hence, the assignment of the observed effects to levels of oxidative stress was also different in vitro and in vivo. However, the overall classification of "active" and "passive" NMs was consistent in vitro and in vivo, suggesting that both cell lines tested are suitable for the assessment of NM toxicity. In summary, the results presented here highlight the need to carefully review model systems to decipher the extent to which they can replace in vivo assays.
Collapse
Affiliation(s)
- Isabel Karkossa
- Department of Molecular Systems Biology, Helmholtz-Centre for Environmental Research - UFZ, Leipzig, Germany
| | - Anne Bannuscher
- Department of Chemical and Product Safety, German Federal Institute for Risk Assessment (BfR), Berlin, Germany; Adolphe Merkle Institute (AMI), University of Fribourg, Fribourg, Switzerland
| | - Bryan Hellack
- Institute of Energy and Environmental Technology (IUTA) e.V., Duisburg, Germany; German Environment Agency (UBA), Dessau, Germany
| | | | - Julie Laloy
- Department of Pharmacy, Namur Nanosafety Centre, University of Namur, Namur, Belgium
| | - Miruna S Stan
- Department of Biochemistry and Molecular Biology, University of Bucharest, Bucharest, Romania
| | - Anca Dinischiotu
- Department of Biochemistry and Molecular Biology, University of Bucharest, Bucharest, Romania
| | - Martin Wiemann
- IBE R&D Institute for Lung Health gGmbH, Münster, Germany
| | - Andreas Luch
- Department of Chemical and Product Safety, German Federal Institute for Risk Assessment (BfR), Berlin, Germany
| | - Andrea Haase
- Department of Chemical and Product Safety, German Federal Institute for Risk Assessment (BfR), Berlin, Germany
| | - Martin von Bergen
- Department of Molecular Systems Biology, Helmholtz-Centre for Environmental Research - UFZ, Leipzig, Germany; Institute of Biochemistry, Leipzig University, Leipzig, Germany
| | - Kristin Schubert
- Department of Molecular Systems Biology, Helmholtz-Centre for Environmental Research - UFZ, Leipzig, Germany.
| |
Collapse
|
8
|
Mohanan PV, Sangeetha V, Sabareeswaran A, Muraleedharan V, Jithin K, Vandana U, Varsha SB. Safety of 0.5% hydrogen peroxide mist used in the disinfection gateway for COVID-19. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2021; 28:66602-66612. [PMID: 34232429 PMCID: PMC8260351 DOI: 10.1007/s11356-021-15164-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/19/2021] [Accepted: 06/23/2021] [Indexed: 04/12/2023]
Abstract
Hydrogen peroxide (H2O2) is a reactive chemical used in a wide range of applications. Most importantly, it is used for sterilization process in health care environment. In the present study, safety assessment of 0.5% of H2O2 and its mist intended to be used in the disinfection gateway for COVID-19 was evaluated. Skin irritation and repeated-dose inhalation toxicity studies were carried out in rabbits and rats, respectively. In Skin irritation study, New Zealand white rabbits were exposed topically with 0.5% H2O2 solution and observed for 24 h, 48 h, and 72 h. For repeated-dose inhalation toxicity study, Wistar rats (both male and female) were exposed (whole body exposure) to 0.5% of H2O2 mist, at a concentration of 11.022 (low dose-2-min exposure), 22.044 (medium dose-4-min exposure), and 55.11mg/kg (high dose/high dose recovery-10-min exposure) body weight, daily for 7 days. Rats in the high-dose recovery group (55.11mg/kg-10-min exposure) were kept for another 7 days without any exposure. A toxicological evaluation was done based on general health parameters, hematology, serum biochemistry, gross necropsy, and histopathological data. The results of the study indicated that there was no skin irritation potential induced on exposure of 0.5% of H2O2 to rabbits. Similarly, the inhalation toxicity of 0.5% of H2O2 mist imparts no evidence of hematological, biochemical, gross pathology, or histopathological abnormalities in rats. Further, at the laboratory condition stimulated, the NOEL was found to be 55.11mg/kg body weight. Hence, the present study concluded that 0.5% H2O2 or its mist used in the disinfection gateway for COVID-19 failed to induce any skin irritation in rabbits or inhalation toxicity in rats. Graphical abstract.
Collapse
Affiliation(s)
- Parayanthala Valappil Mohanan
- Division of Toxicology, Sree Chitra Tirunal Institute for Medical Sciences and Technology (Govt. of India), Biomedical Technology Wing, Poojapura, Trivandrum, Kerala, 695 012, India.
| | - Vijayan Sangeetha
- Division of Toxicology, Sree Chitra Tirunal Institute for Medical Sciences and Technology (Govt. of India), Biomedical Technology Wing, Poojapura, Trivandrum, Kerala, 695 012, India
| | - Arumugham Sabareeswaran
- Division of Histopathology, Sree Chitra Tirunal Institute for Medical Sciences and Technology (Govt. of India), Biomedical Technology Wing, Poojapura, Trivandrum, Kerala, 695 012, India
| | - Vayalappil Muraleedharan
- Division of Artificial Internal Organs, Sree Chitra Tirunal Institute for Medical Sciences and Technology (Govt. of India), Biomedical Technology Wing, Poojapura, Trivandrum, Kerala, 695 012, India
| | - Krishnan Jithin
- Divison of Medical Instrumentation, Sree Chitra Tirunal Institute for Medical Sciences and Technology (Govt. of India), Biomedical Technology Wing, Poojapura, Trivandrum, Kerala, 695 012, India
| | - Unnikrishnan Vandana
- Division of Toxicology, Sree Chitra Tirunal Institute for Medical Sciences and Technology (Govt. of India), Biomedical Technology Wing, Poojapura, Trivandrum, Kerala, 695 012, India
| | - Sheela Bhasi Varsha
- Division of Toxicology, Sree Chitra Tirunal Institute for Medical Sciences and Technology (Govt. of India), Biomedical Technology Wing, Poojapura, Trivandrum, Kerala, 695 012, India
| |
Collapse
|
9
|
Kang Y, Park J, Park H. Particle leakage through the exhalation valve on a face mask under flow conditions mimicking human breathing: A critical assessment. PHYSICS OF FLUIDS (WOODBURY, N.Y. : 1994) 2021; 33:103326. [PMID: 34737532 PMCID: PMC8561653 DOI: 10.1063/5.0067174] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/14/2021] [Accepted: 10/03/2021] [Indexed: 05/19/2023]
Abstract
In today's era of active personal protections against airborne respiratory disease, general interest in the multiphase flow physics underlying face masks is greater than ever. The exhalation valves, installed on some masks to mitigate the breathing resistance, have also received more attention. However, the current certification protocol of evaluating airflow leakage only when suction pressure is applied is insufficient to capture practical aspects (particle penetration or leakage). Here, we experimentally measure two-phase flow across valve-type masks under conditions mimicking actual breathing. During exhalation, a high-speed jet through the valve accelerates the transmission of particles from inside while reasonable protection from external pollutants is achieved during inhalation, which supports the warnings from various public health officials. Based on the mechanism of particle penetration found here, we hope a novel design that both achieves high-efficiency shielding and facilitates easy breathing can be developed.
Collapse
Affiliation(s)
- Yeeun Kang
- Department of Mechanical Engineering, Seoul National University, Seoul 08826, Korea
| | - Jooyeon Park
- Department of Mechanical Engineering, Seoul National University, Seoul 08826, Korea
| | | |
Collapse
|
10
|
da Silva EVF, Goiato MC, Bitencourt SB, Finer Y, Brito VGB, Takamiya AS, de Oliveira SHP, Dos Santos DM. Effect of processing methods on the cytotoxicity of methyl methacrylate-based ocular prostheses: An in vitro study. Toxicol In Vitro 2021; 76:105211. [PMID: 34245821 DOI: 10.1016/j.tiv.2021.105211] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2021] [Revised: 06/29/2021] [Accepted: 07/01/2021] [Indexed: 11/25/2022]
Abstract
The study evaluated the influence of cycles and methods of an ocular prosthesis resin on cytotoxicity toward human conjunctival cells. Resins were polymerized by water bath (WB, 74 °C or 100 °C for 30 min to 9 h), microwave (MW, 1200 W, 3 to 14 min and 30 s at 0 to 720 W), or autopolymerization (AP, room temperature for 20 min ± 60 °C for 30 min). Degree of conversion (DC), cytotoxicity, level of inflammatory mediators, gene expression of different markers, and apoptosis were evaluated. Data were submitted to ANOVA and Tukey test (p < 0.05). WB with longer processing time at higher temperature had highest DC (85.6%) and higher TGF β1-gene expression (1.39); long cycle low power MW showed lowest DC (69.6%), lower cell proliferation (85.4%, MTT), and large IL-2 release (39,297 ng/mL). AP with additional processing time showed lower cell proliferation (75.3%, Alamar Blue), and AP polymerized at room temperature showed higher CASP 9-gene expression (1.21). AP methods showed higher IL-6 release (>277 pg/mL). Short cycle medium power MW had higher IL-23 release (534.2 pg/mL). MW (long and short cycles) and AP polymerizations have triggered a more intense inflammatory response. Among methods recommended by the manufacturer, WB showed high DC and less cytotoxicity.
Collapse
Affiliation(s)
- Emily Vivianne Freitas da Silva
- Department of Dental Materials and Prosthodontics, Aracatuba Dental School, Sao Paulo State University (UNESP), Aracatuba, Sao Paulo, Brazil
| | - Marcelo Coelho Goiato
- Department of Dental Materials and Prosthodontics, Aracatuba Dental School, UNESP, Aracatuba, Sao Paulo, Brazil; Oral Oncology Center, São Paulo State University (Unesp), School of Dentistry, 1193 José Bonifácio St, Araçatuba, São Paulo 15050-015, Brazil.
| | - Sandro Basso Bitencourt
- Department of Dental Materials and Prosthodontics, Aracatuba Dental School, Sao Paulo State University (UNESP), Aracatuba, Sao Paulo, Brazil
| | - Yoav Finer
- Faculty of Dentistry, University of Toronto, Toronto, Ontario, Canada; Institute of Biomedical Engineering, University of Toronto, Ontario, Canada
| | | | - Aline Satie Takamiya
- Oral Oncology Center, São Paulo State University (Unesp), School of Dentistry, 1193 José Bonifácio St, Araçatuba, São Paulo 15050-015, Brazil; Institute of Biomedical Engineering, University of Toronto, Ontario, Canada
| | - Sandra Helena Penha de Oliveira
- Oral Oncology Center, São Paulo State University (Unesp), School of Dentistry, 1193 José Bonifácio St, Araçatuba, São Paulo 15050-015, Brazil; Department of Basic Sciences, Aracatuba Dental School, UNESP, Aracatuba, Sao Paulo, Brazil
| | - Daniela Micheline Dos Santos
- Department of Dental Materials and Prosthodontics, Aracatuba Dental School, UNESP, Aracatuba, Sao Paulo, Brazil; Oral Oncology Center, São Paulo State University (Unesp), School of Dentistry, 1193 José Bonifácio St, Araçatuba, São Paulo 15050-015, Brazil
| |
Collapse
|
11
|
Ling YTQ, Heng YX, Chan HH, Yap YJ, Lee SY, Koh RY, Liew YK, Manaf SNQ, Ang DTC, Mok KL. Evaluation of biocompatible palm-based polymeric surfactants for potential natural rubber latex stabilisation applications. J RUBBER RES 2021. [DOI: 10.1007/s42464-021-00104-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
|
12
|
Khalil C, Chahine JB, Haykal T, Al Hageh C, Rizk S, Khnayzer RS. E-cigarette aerosol induced cytotoxicity, DNA damages and late apoptosis in dynamically exposed A549 cells. CHEMOSPHERE 2021; 263:127874. [PMID: 33297006 DOI: 10.1016/j.chemosphere.2020.127874] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/29/2020] [Revised: 06/15/2020] [Accepted: 07/27/2020] [Indexed: 06/12/2023]
Abstract
In this study, the acute toxicological impacts associated with electronic cigarettes consumption were determined using a novel dynamic exposure methodology. The methodology was deployed to test various e-cigarette generated aerosols in A549 cell cultures. The e-liquid chemical profiling was achieved using GC-MS analysis while toxicity of diluted e-liquids aerosols was reported using numerous cytotoxicity assays. The presented findings pointed to acute aerosol exposure (thirty puffs at 40 W of power and higher) inducing significant cytotoxic, genotoxic, and apoptotic induction in exposed cells. These findings highlighted the significant risks posed by e-cigarette usage. The proposed methodology proved to be a useful tool for future screening of e-liquids generated aerosols toxicity. Future research is needed to establish the chronic toxicity resulting from long-term e-cigarette consumption.
Collapse
Affiliation(s)
- Christian Khalil
- School of Arts and Sciences, Department of Natural Sciences, Lebanese American University (LAU), Byblos, Lebanon; Department of Natural Sciences, Lebanese American University, Chouran, Beirut, 1102-2801, Lebanon.
| | - Joe Braham Chahine
- School of Arts and Sciences, Department of Natural Sciences, Lebanese American University (LAU), Byblos, Lebanon
| | - Tony Haykal
- School of Arts and Sciences, Department of Natural Sciences, Lebanese American University (LAU), Byblos, Lebanon
| | - Cynthia Al Hageh
- School of Arts and Sciences, Department of Natural Sciences, Lebanese American University (LAU), Byblos, Lebanon
| | - Sandra Rizk
- School of Arts and Sciences, Department of Natural Sciences, Lebanese American University (LAU), Byblos, Lebanon
| | - Rony S Khnayzer
- Department of Natural Sciences, Lebanese American University, Chouran, Beirut, 1102-2801, Lebanon
| |
Collapse
|
13
|
Tallandier V, Merlen L, Boucard S, Thomas A, Venet T, Chalansonnet M, Gauchard G, Campo P, Pouyatos B. Styrene alters potassium endolymphatic concentration in a model of cultured utricle explants. Toxicol In Vitro 2020; 67:104915. [PMID: 32540163 DOI: 10.1016/j.tiv.2020.104915] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2020] [Revised: 06/02/2020] [Accepted: 06/11/2020] [Indexed: 12/23/2022]
Abstract
Despite well-documented neurotoxic and ototoxic properties, styrene remains commonly used in industry. Its effects on the cochlea have been extensively studied in animals, and epidemiological and animal evidence indicates an impact on balance. However, its influence on the peripheral vestibular receptor has yet to be investigated. Here, we assessed the vestibulotoxicity of styrene using an in vitro model, consisting of three-dimensional cultured newborn rat utricles filled with a high‑potassium (K+) endolymph-like fluid, called "cysts". K+ entry in the cyst ("influx") and its exit ("efflux") are controlled by secretory cells and hair cells, respectively. The vestibular epithelium's functionality is thus linked to K+ concentration, measured using a microelectrode. Known inhibitors of K+ efflux and influx validated the model. Cysts were subsequently exposed to styrene (0.25; 0.5; 0.75 and 1 mM) for 2 h or 72 h. The decrease in K+ concentration measured after both exposure durations was dose-dependent, and significant from 0.75 mM styrene. Vacuoles were visible in the cytoplasm of epithelial cells from 0.5 mM after 2 h and from 0.25 mM after 72 h. The results presented here are the first evidence that styrene may deregulate K+ homeostasis in the endolymphatic space, thereby altering the functionality of the vestibular receptor.
Collapse
Affiliation(s)
- V Tallandier
- Institut National de Recherche et de Sécurité, Rue du Morvan, CS 60027, F-54519 Vandœuvre, Cedex, France; DevAH EA 3450 - Développement, Adaptation et Handicap, Régulations cardio-respiratoires et de la motricité-Université de Lorraine, F-54500 Vandœuvre, France
| | - L Merlen
- Institut National de Recherche et de Sécurité, Rue du Morvan, CS 60027, F-54519 Vandœuvre, Cedex, France
| | - S Boucard
- Institut National de Recherche et de Sécurité, Rue du Morvan, CS 60027, F-54519 Vandœuvre, Cedex, France
| | - A Thomas
- Institut National de Recherche et de Sécurité, Rue du Morvan, CS 60027, F-54519 Vandœuvre, Cedex, France
| | - T Venet
- Institut National de Recherche et de Sécurité, Rue du Morvan, CS 60027, F-54519 Vandœuvre, Cedex, France; DevAH EA 3450 - Développement, Adaptation et Handicap, Régulations cardio-respiratoires et de la motricité-Université de Lorraine, F-54500 Vandœuvre, France
| | - M Chalansonnet
- Institut National de Recherche et de Sécurité, Rue du Morvan, CS 60027, F-54519 Vandœuvre, Cedex, France.
| | - G Gauchard
- DevAH EA 3450 - Développement, Adaptation et Handicap, Régulations cardio-respiratoires et de la motricité-Université de Lorraine, F-54500 Vandœuvre, France
| | - P Campo
- Institut National de Recherche et de Sécurité, Rue du Morvan, CS 60027, F-54519 Vandœuvre, Cedex, France; DevAH EA 3450 - Développement, Adaptation et Handicap, Régulations cardio-respiratoires et de la motricité-Université de Lorraine, F-54500 Vandœuvre, France
| | - B Pouyatos
- Institut National de Recherche et de Sécurité, Rue du Morvan, CS 60027, F-54519 Vandœuvre, Cedex, France
| |
Collapse
|
14
|
Areecheewakul S, Adamcakova-Dodd A, Givens BE, Steines BR, Wang Y, Meyerholz DK, Parizek NJ, Altmaier R, Haque E, O’Shaughnessy PT, Salem AK, Thorne PS. Toxicity assessment of metal oxide nanomaterials using in vitro screening and murine acute inhalation studies. NANOIMPACT 2020; 18:100214. [PMID: 32968700 PMCID: PMC7504913 DOI: 10.1016/j.impact.2020.100214] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
Characterizations and in vitro toxicity screening were performed on metal oxide engineered nanomaterials (ENMs) independently comprising ZnO, CuO, CeO2, Fe2O3, WO3, V2O5, TiO2, Al2O3 and MgO. Nanomaterials that exhibited the highest toxicity responses in the in vitro screening assays (ZnO, CuO, and V2O5) and the lesser explored material WO3 were tested for acute pulmonary toxicity in vivo. Female and male mice (C57Bl/6J) were exposed to aerosolized metal oxide ENMs in a nose-only exposure system and toxicity outcomes (biomarkers of cytotoxicity, immunotoxicity, inflammation, and lung histopathology) at 4 and 24 h after the start of exposure were assessed. The studies were performed as part of the NIEHS Nanomaterials Health Implications Research consortium with the purpose of investigating the effects of ENMs on various biological systems. ENMs were supplied by the Engineered Nanomaterials Resource and Coordination Core. Among the ENMs studied, the highest toxicity was observed for CuO and ZnO NPs in both in vitro and in vivo acute models. Compared to sham-exposed controls, there was a significant increase in bronchoalveolar lavage neutrophils and proinflammatory cytokines and a loss of macrophage viability at both 4 h and 24 h for ZnO and CuO but not seen for V2O5 or WO3. These effects were observed in both female and male mice. The cell viability performed after in vitro exposure to ENMs and assessment of lung inflammation after acute inhalation exposure in vivo were shown to be sensitive endpoints to predict ENM acute toxicity.
Collapse
Affiliation(s)
- Sudartip Areecheewakul
- Department of Pharmaceutical Sciences and Experimental Therapeutics, University of Iowa, Iowa City, IA 52246, USA
| | - Andrea Adamcakova-Dodd
- Department of Occupational and Environmental Health, University of Iowa, Iowa City, IA 52246, USA
| | - Brittany E. Givens
- Department of Pharmaceutical Sciences and Experimental Therapeutics, University of Iowa, Iowa City, IA 52246, USA
| | - Benjamin R. Steines
- Department of Occupational and Environmental Health, University of Iowa, Iowa City, IA 52246, USA
| | - Yifang Wang
- Interdisciplinary Graduate Program in Human Toxicology, University of Iowa, Iowa City, IA 52246, USA
| | | | - Nathanial J. Parizek
- Interdisciplinary Graduate Program in Human Toxicology, University of Iowa, Iowa City, IA 52246, USA
| | - Ralph Altmaier
- Department of Occupational and Environmental Health, University of Iowa, Iowa City, IA 52246, USA
| | - Ezazul Haque
- Interdisciplinary Graduate Program in Human Toxicology, University of Iowa, Iowa City, IA 52246, USA
| | - Patrick T. O’Shaughnessy
- Department of Occupational and Environmental Health, University of Iowa, Iowa City, IA 52246, USA
| | - Aliasger K. Salem
- Department of Pharmaceutical Sciences and Experimental Therapeutics, University of Iowa, Iowa City, IA 52246, USA
- Corresponding author
| | - Peter S. Thorne
- Department of Occupational and Environmental Health, University of Iowa, Iowa City, IA 52246, USA
- Interdisciplinary Graduate Program in Human Toxicology, University of Iowa, Iowa City, IA 52246, USA
- Correspondence to: P.S. Thorne, Department of Occupational and Environmental Health, The University of Iowa, College of Public Health, 145 N. Riverside Dr., S341A CPHB, Iowa City, IA 52242, USA. (A.K. Salem), (P.S. Thorne)
| |
Collapse
|
15
|
Khalil C, Chahine JB, Chahla B, Hobeika T, Khnayzer RS. Characterization and cytotoxicity assessment of nargile smoke using dynamic exposure. Inhal Toxicol 2019; 31:343-356. [DOI: 10.1080/08958378.2019.1683104] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Affiliation(s)
- Christian Khalil
- Department of Natural Sciences, School of Arts and Sciences, Lebanese American University, Byblos, Lebanon
- Institute of Environmental Studies, University of New South Wales (UNSW), Sydney, Australia
| | - Joe Braham Chahine
- Department of Natural Sciences, School of Arts and Sciences, Lebanese American University, Byblos, Lebanon
| | - Brenda Chahla
- Department of Natural Sciences, School of Arts and Sciences, Lebanese American University, Byblos, Lebanon
| | - Tamara Hobeika
- Department of Natural Sciences, School of Arts and Sciences, Lebanese American University, Byblos, Lebanon
| | - Rony S. Khnayzer
- Department of Natural Sciences, Lebanese American University, Chouran, Beirut, Lebanon
| |
Collapse
|
16
|
Rabel M, Warncke P, Grüttner C, Bergemann C, Kurland HD, Müller R, Dugandžić V, Thamm J, Müller FA, Popp J, Cialla-May D, Fischer D. Simulation of the long-term fate of superparamagnetic iron oxide-based nanoparticles using simulated biological fluids. Nanomedicine (Lond) 2019; 14:1681-1706. [DOI: 10.2217/nnm-2018-0382] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Aim: To simulate the stability and degradation of superparamagnetic iron oxide nanoparticles (MNP) in vitro as part of their life cycle using complex simulated biological fluids. Materials & methods: A set of 13 MNP with different polymeric or inorganic shell materials was synthesized and characterized regarding stability and degradation of core and shell in simulated biological fluids. Results: All MNP formulations showed excellent stability during storage and in simulated body fluid. In endosomal/lysosomal media the degradation behavior depended on shell characteristics (e.g., charge, acid-base character) and temperature enabling the development of an accelerated stress test protocol. Conclusion: Kinetics of transformations depending on the MNP type could be established to define structure-activity relationships as prediction model for rational particle design.
Collapse
Affiliation(s)
- Martin Rabel
- Pharmaceutical Technology & Biopharmacy, Friedrich Schiller University Jena, Lessingstraße 8, 07743 Jena, Germany
| | - Paul Warncke
- Pharmaceutical Technology & Biopharmacy, Friedrich Schiller University Jena, Lessingstraße 8, 07743 Jena, Germany
| | - Cordula Grüttner
- Micromod Partikeltechnologie GmbH, Friedrich-Barnewitz-Straße 4, 18119 Rostock, Germany
| | | | - Heinz-Dieter Kurland
- Otto Schott Institute of Materials Research, Friedrich Schiller University Jena, Löbdergraben 32, 07743 Jena, Germany
| | - Robert Müller
- Leibniz Institute of Photonic Technology, Albert-Einstein-Straße 9, 07745 Jena, Germany
| | - Vera Dugandžić
- Leibniz Institute of Photonic Technology, Albert-Einstein-Straße 9, 07745 Jena, Germany
| | - Jana Thamm
- Pharmaceutical Technology & Biopharmacy, Friedrich Schiller University Jena, Lessingstraße 8, 07743 Jena, Germany
| | - Frank A. Müller
- Otto Schott Institute of Materials Research, Friedrich Schiller University Jena, Löbdergraben 32, 07743 Jena, Germany
| | - Jürgen Popp
- Leibniz Institute of Photonic Technology, Albert-Einstein-Straße 9, 07745 Jena, Germany
- Institute of Physical Chemistry, Friedrich Schiller University Jena, Helmholtzweg 4, 07743 Jena, Germany
| | - Dana Cialla-May
- Leibniz Institute of Photonic Technology, Albert-Einstein-Straße 9, 07745 Jena, Germany
- Institute of Physical Chemistry, Friedrich Schiller University Jena, Helmholtzweg 4, 07743 Jena, Germany
| | - Dagmar Fischer
- Pharmaceutical Technology & Biopharmacy, Friedrich Schiller University Jena, Lessingstraße 8, 07743 Jena, Germany
| |
Collapse
|
17
|
Ishikawa S, Matsumura K, Kitamura N, Takanami Y, Ito S. Multi-omics analysis: Repeated exposure of a 3D bronchial tissue culture to whole-cigarette smoke. Toxicol In Vitro 2019; 54:251-262. [PMID: 30291989 DOI: 10.1016/j.tiv.2018.10.001] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2018] [Revised: 08/09/2018] [Accepted: 10/01/2018] [Indexed: 02/02/2023]
Abstract
Cigarette smoke (CS) is a major risk factor in the development of chronic inflammatory lung diseases such as chronic obstructive pulmonary disease. A comprehensive investigation of the biological impacts of chronic CS exposure on lung tissue is therefore important for understanding the pathogenesis of lung disease. We used three-dimensional (3D) organotypic human bronchial tissue cultures and metabolomics, transcriptomics, and proteomics to investigate changes in biological processes affected by repeated whole-CS exposure. We found that CS perturbed central carbon metabolism in relation with oxidative stress responses. Epidermal growth factor receptor, which is involved in the early-stage pathogenesis of airway diseases, was identified as a key regulator of the perturbed processes. Proteomic analysis of proteins in the apical surface liquid of the 3D bronchial tissue cultures indicated that repeated whole-CS exposure induced alterations in the secretion of several known biomarkers of airway diseases, including mucins and matrix metalloproteinases. These findings are consistent with observations from lung disease patients. Overall, our results suggest that 3D bronchial tissue cultures can provide valuable information on tissue-specific alterations in biological processes induced by chronic exposure to CS.
Collapse
Affiliation(s)
- Shinkichi Ishikawa
- Scientific Product Assessment Center, R&D Group, Japan Tobacco Inc., 6-2 Umegaoka, Aoba-ku, Yokohama, Kanagawa 227-8512, Japan.
| | - Kazushi Matsumura
- Scientific Product Assessment Center, R&D Group, Japan Tobacco Inc., 6-2 Umegaoka, Aoba-ku, Yokohama, Kanagawa 227-8512, Japan.
| | - Nobumasa Kitamura
- Scientific Product Assessment Center, R&D Group, Japan Tobacco Inc., 6-2 Umegaoka, Aoba-ku, Yokohama, Kanagawa 227-8512, Japan.
| | - Yuichiro Takanami
- Scientific Product Assessment Center, R&D Group, Japan Tobacco Inc., 6-2 Umegaoka, Aoba-ku, Yokohama, Kanagawa 227-8512, Japan.
| | - Shigeaki Ito
- Scientific Product Assessment Center, R&D Group, Japan Tobacco Inc., 6-2 Umegaoka, Aoba-ku, Yokohama, Kanagawa 227-8512, Japan.
| |
Collapse
|
18
|
Ke S, Liu Q, Deng M, Zhang X, Yao Y, Shan M, Yang X, Sui G. Cytotoxicity analysis of indoor air pollution from biomass combustion in human keratinocytes on a multilayered dynamic cell culture platform. CHEMOSPHERE 2018; 208:1008-1017. [PMID: 30068025 DOI: 10.1016/j.chemosphere.2018.06.058] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/27/2018] [Accepted: 06/07/2018] [Indexed: 06/08/2023]
Abstract
Skin tissue is the first barrier against ambient harmful matter and has direct contact with indoor air pollutants. Nevertheless, a comprehensive understanding of cytotoxicity of indoor air pollution on skin cells is insufficiently clear. Herein, for the first time a multilayered dynamic cell culture platform was established to study the cytotoxicity of indoor air pollutant from biomass combustion in human skin keratinocytes. The platform consisted of seven repetitive polydimethylsiloxane modules carrying six pieces of polycarbonate membrane between them as substrate for cell growth to realize the simultaneous dynamic culture of 12 layers of keratinocytes. After exposure to biomass combustion soluble constituents (BCSCs), cell viability under microfluidic platform conditions declined more significantly, and apoptosis rates increased more obviously compared with well plate conditions. Transmission electron microscope showed that keratinocyte microstructures displayed obvious signs of cellular damage. Our study confirmed that the nuclear factor of kappa B (NF-κB) signaling pathway was activated, which significantly increased the Bax/Bcl-2 ratio and tumor necrosis factor-alpha and interleukin 6 expression, indicating that NF-κB signaling pathway was the major factor in BCSCs-induced cytotoxicity. These findings offer an insight into the mechanism of BCSCs-induced cytotoxicity in keratinocytes and provide a theoretical basis for future studies on skin cells.
Collapse
Affiliation(s)
- Shaorui Ke
- Shanghai Key Laboratory of Atmospheric Particle Pollution Prevention (LAP3), Department of Environmental Science & Engineering, Fudan University, Shanghai 200433, PR China
| | - Qi Liu
- Shanghai Key Laboratory of Atmospheric Particle Pollution Prevention (LAP3), Department of Environmental Science & Engineering, Fudan University, Shanghai 200433, PR China
| | - Mengsi Deng
- Department of Building Science, Tsinghua University, Beijing 100084, PR China
| | - Xinlian Zhang
- Shanghai Key Laboratory of Atmospheric Particle Pollution Prevention (LAP3), Department of Environmental Science & Engineering, Fudan University, Shanghai 200433, PR China
| | - Yuhan Yao
- Shanghai Key Laboratory of Atmospheric Particle Pollution Prevention (LAP3), Department of Environmental Science & Engineering, Fudan University, Shanghai 200433, PR China
| | - Ming Shan
- Department of Building Science, Tsinghua University, Beijing 100084, PR China
| | - Xudong Yang
- Department of Building Science, Tsinghua University, Beijing 100084, PR China.
| | - Guodong Sui
- Shanghai Key Laboratory of Atmospheric Particle Pollution Prevention (LAP3), Department of Environmental Science & Engineering, Fudan University, Shanghai 200433, PR China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, PR China.
| |
Collapse
|
19
|
Kim YH, An YJ, Jo S, Lee SH, Lee SJ, Choi SJ, Lee K. Comparison of volatile organic compounds between cigarette smoke condensate (CSC) and extract (CSE) samples. ENVIRONMENTAL HEALTH AND TOXICOLOGY 2018; 33:e2018012-0. [PMID: 30286588 PMCID: PMC6182245 DOI: 10.5620/eht.e2018012] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/17/2018] [Accepted: 08/27/2018] [Indexed: 06/08/2023]
Abstract
Cigarette smoke is a major risk factor for several diseases, including chronic obstructive pulmonary and cardiovascular diseases. The toxicity of the cigarette smoke can be determined in vitro. The cytotoxicity test of the cigarette smoke is commonly conducted using the cigarette smoke condensate (CSC) and cigarette smoke extract (CSE). The CSC and CSE methods are well known for sampling of the particles and water-soluble compounds in the cigarette smoke, respectively. In this study, the CSC and CSE were analyzed by using a gas chromatography-mass spectrometry (GC-MS) system equipped with a wax column for separation of the volatile organic compounds. The cytotoxic effect of the CSC and CSE were evaluated thoroughly by comparing the analytical results of the CSC and CSE samples. The total concentration of the volatile organic compounds detected in the CSC sample was similar to that in the CSE sample based on the peak area. Except for the dimethyl sulfoxide solvent, nicotine had the highest concentration in the CSC sample, while acetonitrile had the highest concentration in the CSE sample. The compositions were as follows: (1) CSC sample: 55.8% nicotine, 18.0% nicotyrine, 3.20% 1,2,3-propanetriol, triacetate, 1.28% ethyl chloride, 1.22% phenol, etc. and (2) CSE sample: 18.7% acetonitrile, 18.0% acetone, 12.5% 2-hydroxy-2-methyl-propanenitrile, 8.98% nicotine, 5.86% nicotyrine, etc. In this manner, to accurately examine the cytotoxicity of the cigarette smoke using CSC or CSE, the components and their concentrations in the CSC and CSE samples should be considered.
Collapse
Affiliation(s)
- Yong-Hyun Kim
- Jeonbuk Department of Inhalation Research, Korea Institute of Toxicology, Jeongeup 56212, Republic of Korea
- Human and Environmental Toxicology, University of Science and Technology, Daejeon 34113, Republic of Korea
| | - Young-Ji An
- Department of Toxicology Evaluation, Konyang University, Daejeon 35365 Republic of Korea
- National Center for Efficacy Evaluation of Respiratory Disease Product, Korea Institute of Toxicology, Jeongeup 56212, Republic of Korea
| | - Seongwon Jo
- Jeonbuk Department of Inhalation Research, Korea Institute of Toxicology, Jeongeup 56212, Republic of Korea
| | - Sang-Hyub Lee
- Jeonbuk Department of Inhalation Research, Korea Institute of Toxicology, Jeongeup 56212, Republic of Korea
| | - Sang Jin Lee
- National Center for Efficacy Evaluation of Respiratory Disease Product, Korea Institute of Toxicology, Jeongeup 56212, Republic of Korea
| | - Seong-Jin Choi
- Jeonbuk Department of Inhalation Research, Korea Institute of Toxicology, Jeongeup 56212, Republic of Korea
| | - Kyuhong Lee
- Human and Environmental Toxicology, University of Science and Technology, Daejeon 34113, Republic of Korea
- National Center for Efficacy Evaluation of Respiratory Disease Product, Korea Institute of Toxicology, Jeongeup 56212, Republic of Korea
| |
Collapse
|
20
|
Ito S, Ishimori K, Ishikawa S. Effects of repeated cigarette smoke extract exposure over one month on human bronchial epithelial organotypic culture. Toxicol Rep 2018; 5:864-870. [PMID: 30167377 PMCID: PMC6111042 DOI: 10.1016/j.toxrep.2018.08.015] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2018] [Revised: 08/03/2018] [Accepted: 08/16/2018] [Indexed: 12/20/2022] Open
Abstract
Cigarette smoke is a known risk factor for inflammatory diseases in the respiratory tract, and inflammatory exacerbation is considered pivotal to the pathogenesis of these diseases. Here, we performed two repeated exposure studies in which we exposed human bronchial epithelial tissues in an organotypic culture model to cigarette smoke extract (CSE); the first study was conducted over a four-day period to determine the suitable dose range for the extended exposure period, and the second was a one-month exposure study to elucidate the exposure-by-exposure effects in bronchial tissues. We focused on matrix metalloproteinase (MMP)-9 and -1/3 and the inflammatory cytokines interleukin (IL)-8 and growth factor related oncogene to evaluate the transition into an inflammatory state. Even at CSE doses with no or low toxicity for a single exposure, the repetition of exposure induced cumulative effects on both the inflammatory responses, specifically the IL-8 and MMPs levels, and tissue morphology. Interestingly, untreated controls initially had relatively high baseline levels of these secreted proteins; these levels gradually declined, after which they showed periodic level changes, suggesting an acclimation period may be needed for this system. These results demonstrate the usability of this system for the elucidation of sub-chronic effects in vitro.
Collapse
Key Words
- COPD, chronic obstructive pulmonary disease
- CS, cigarette smoke
- Cigarette smoke extract
- GRO, growth factor related oncogene
- IL, interleukin
- IP-10, interferon gamma-induced protein-10
- MCP-1, monocyte chemotactic protein-1
- MIP-1β, macrophage inflammatory protein-1β
- MMP, metalloproteinase
- Organotypic culture
- RANTES, regulated on activation normal T cell expressed and secreted
- Repeated exposure
- SDF-1α, stromal cell-derived factor-1α
Collapse
Affiliation(s)
- Shigeaki Ito
- Scientific Product Assessment Center, R&D Group, Japan Tobacco Inc., 6-2, Umegaoka, Aoba-ku, Yokohama, Kanagawa, 227-8512, Japan
| | - Kanae Ishimori
- Scientific Product Assessment Center, R&D Group, Japan Tobacco Inc., 6-2, Umegaoka, Aoba-ku, Yokohama, Kanagawa, 227-8512, Japan
| | - Shinkichi Ishikawa
- Scientific Product Assessment Center, R&D Group, Japan Tobacco Inc., 6-2, Umegaoka, Aoba-ku, Yokohama, Kanagawa, 227-8512, Japan
| |
Collapse
|
21
|
Potential and Actual Health Hazards in the Dense Urban Operational Environment: Critical Gaps and Solutions for Military Occupational Health. J Occup Environ Med 2018; 59:e197-e203. [PMID: 28795994 DOI: 10.1097/jom.0000000000001118] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
: This paper presents environmental health risks which are prevalent in dense urban environments.We review the current literature and recommendations proposed by environmental medicine experts in a 2-day symposium sponsored by the Department of Defense and supported by the Johns Hopkins University Applied Physics Laboratory.Key hazards in the dense urban operational environment include toxic industrial chemicals and materials, water pollution and sewage, and air pollution. Four critical gaps in environmental medicine were identified: prioritizing chemical and environmental concerns, developing mobile decision aids, personalized health assessments, and better real-time health biomonitoring.As populations continue to concentrate in cities, civilian and military leaders will need to meet emerging environmental health concerns by developing and delivering adequate technology and policy solutions.
Collapse
|
22
|
Kim HY, Cho ES. 28-day inhalation toxicity of 3-methoxybutyl chloroformate in rats. Toxicol Rep 2018; 5:213-219. [PMID: 29854591 PMCID: PMC5977156 DOI: 10.1016/j.toxrep.2017.12.007] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2017] [Revised: 09/23/2017] [Accepted: 12/08/2017] [Indexed: 11/17/2022] Open
Abstract
3-MBCF up to 6 ppm induced mortality in 28-day inhalation study of rats. The NOAEL of 3-MBCF in 28 day inhalation toxicity study, was less than 3 ppm. 3-MBCF under 12 ppm did not induce micronucleus formation in the bone marrow of rats.
The 28-day repeated inhalation study was applied for hazard assessment of 3-methoxybutyl chloroformate (3-MBCF) in Sprague Dawley rats. Groups of five rats per sex were exposed 6 h/day, 5 days per week for 4 weeks to test substance concentration (ranging from 3 to 12 ppm) using a whole-body exposure system. At the terminal sacrifice, following blood collection and gross pathological examination, organ weights were determined and fixed organs were examined. The micronucleus test was performed using bone marrow cells. Exposure of 3-MBCF induced mortality at concentrations above 6 ppm. Decreases in body weight and food intake, hematologic alterations, organ weight changes, and gross and microscopic findings were seen even at the lowest concentrations of 3 ppm. Histopathology revealed principal test substance exposure correlated with lesions in the respiratory tract in both male and female rats above 3 ppm. Groups of male rats exposed above 6 ppm show microscopic lesions in spleens, livers, testes and epididymides; however, the micronucleated polychromatic erythrocytes frequency in bone marrow cells was not changed. Based on histopathology of the respiratory tract and other organs, the no observed adverse effect level (NOAEL) of 3-MBCF in the present study was less than 3 ppm.
Collapse
Key Words
- 3-MBCF, 3-methoxy butyl chloroformate
- 3-Methoxybutyl chloroformate
- ANOVA, analysis of variance
- CT, computed tomography
- EDTA, ethylenediamine tetraacetic acid
- GHS, Globally Harmonized System of Classification and Labelling of Chemicals
- GLP, Good Laboratory Practice
- HCT, hematocrit
- HGB, hemoglobin concentration
- Inhalation toxicity
- MCH, mean corpuscular hemoglobin
- MCHC, mean corpuscular hemoglobin concentration
- MCV, mean corpuscular volume
- MNPCE, micronucleated polychromatic erythrocytes
- MOE, The Ministry of Environment
- NCE, normochromatic erythrocytes
- NOAEL, no observed adverse effect level
- OECD, Organization for Economic Cooperation and Development
- PCE, polychromatic erythrocytes
- PLT, platelets
- RBC, red blood cell counts
- RDW, red cell distribution width
- REACH, Registration, Evaluation, Authorization and Restriction of Chemicals
- SD, Sprague-Dawley
- SPF, specific-pathogen-free
- Sprague Dawley rats
- WBC, white blood cell counts
- occupational hazard
Collapse
|
23
|
Jackson GR, Maione AG, Klausner M, Hayden PJ. Prevalidation of an Acute Inhalation Toxicity Test Using the EpiAirway In Vitro Human Airway Model. ACTA ACUST UNITED AC 2018; 4:149-158. [PMID: 29904643 PMCID: PMC5994905 DOI: 10.1089/aivt.2018.0004] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Introduction: Knowledge of acute inhalation toxicity potential is important for establishing safe use of chemicals and consumer products. Inhalation toxicity testing and classification procedures currently accepted within worldwide government regulatory systems rely primarily on tests conducted in animals. The goal of the current work was to develop and prevalidate a nonanimal (in vitro) test for determining acute inhalation toxicity using the EpiAirway™ in vitro human airway model as a potential alternative for currently accepted animal tests. Materials and Methods: The in vitro test method exposes EpiAirway tissues to test chemicals for 3 hours, followed by measurement of tissue viability as the test endpoint. Fifty-nine chemicals covering a broad range of toxicity classes, chemical structures, and physical properties were evaluated. The in vitro toxicity data were utilized to establish a prediction model to classify the chemicals into categories corresponding to the currently accepted Globally Harmonized System (GHS) and the Environmental Protection Agency (EPA) system. Results: The EpiAirway prediction model identified in vivo rat-based GHS Acute Inhalation Toxicity Category 1–2 and EPA Acute Inhalation Toxicity Category I–II chemicals with 100% sensitivity and specificity of 43.1% and 50.0%, for GHS and EPA acute inhalation toxicity systems, respectively. The sensitivity and specificity of the EpiAirway prediction model for identifying GHS specific target organ toxicity-single exposure (STOT-SE) Category 1 human toxicants were 75.0% and 56.5%, respectively. Corrosivity and electrophilic and oxidative reactivity appear to be the predominant mechanisms of toxicity for the most highly toxic chemicals. Conclusions: These results indicate that the EpiAirway test is a promising alternative to the currently accepted animal tests for acute inhalation toxicity.
Collapse
|
24
|
Yazdimamaghani M, Barber ZB, Hadipour Moghaddam SP, Ghandehari H. Influence of Silica Nanoparticle Density and Flow Conditions on Sedimentation, Cell Uptake, and Cytotoxicity. Mol Pharm 2018; 15:2372-2383. [PMID: 29719153 DOI: 10.1021/acs.molpharmaceut.8b00213] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Careful evaluation of the toxicological response of engineered nanomaterials (ENMs) as a function of physicochemical properties can aid in the design of safe platforms for biomedical applications including drug delivery. Typically, in vitro ENM cytotoxicity assessments are performed under conventional static cell culture conditions. However, such conditions do not take into account the sedimentation rate of ENMs. Herein, we synthesized four types of similar size silica nanoparticles (SNPs) with modified surface roughness, charge, and density and characterized their cytotoxicity under static and dynamic conditions. Influence of particle density on sedimentation and diffusion velocities were studied by comparing solid dense silica nanoparticles of approximately 350 nm in diameter with hollow rattle shape particles of similar size. Surface roughness and charge had negligible impact on sedimentation and diffusion velocities. Lower cellular uptake and toxicity was observed by rattle particles and under dynamic conditions. Dosimetry of ENMs are primarily reported by particle concentration, assuming homogeneous distribution of nanoparticles in cell culture media. However, under static conditions, nanoparticles tend to sediment at a higher rate due to gravitational forces and hence increase effective doses of nanoparticles exposed to cells. By introducing shear flow to SNP suspensions, we reduced sedimentation and nonhomogeneous particle distribution. These results have implications for design of in vitro cytotoxicity assessment of ENMs and suggest that among other factors, sedimentation of nanoparticles in toxicity assessment should be carefully considered.
Collapse
|
25
|
Fowler K, Fields W, Hargreaves V, Reeve L, Bombick B. Development, qualification, validation and application of the Ames test using a VITROCELL ® VC10 ® smoke exposure system. Toxicol Rep 2018; 5:542-551. [PMID: 29854624 PMCID: PMC5977537 DOI: 10.1016/j.toxrep.2018.04.003] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2017] [Revised: 03/09/2018] [Accepted: 04/06/2018] [Indexed: 01/08/2023] Open
Abstract
Smoke-induced mutagenicity at air agar interface was developed and validated. The VITROCELL® VC10® system was validated by equipment qualification protocols. Differentiation of mutagenicity by 3R4F and Eclipse cigarettes was demonstrated.
The Ames test has established use in the assessment of potential mutagenicity of tobacco products but has generally been performed using partitioned exposures (e.g. total particulate matter [TPM], gas vapor phase [GVP]) rather than whole smoke (WS). The VITROCELL®VC10® smoke exposure system offers multiple platforms for air liquid interface (ALI), or air agar interface (AAI) in the case of the Ames test exposure to mimic in vivo-like conditions for assessing the toxicological impact of fresh WS in in vitro assays. The goals of this study were to 1) qualify the VITROCELL®VC10® to demonstrate functionality of the system, 2) develop and validate the Ames test following WS exposure with the VITROCELL®VC10® and 3) assess the ability of the Ames test to differentiate between a reference combustible product (3R4F Kentucky reference cigarette) and a primarily tobacco heating product (Eclipse). Based on critical function assessments, the VITROCELL®VC10® was demonstrated to be fit for the purpose of consistent generation of WS. Assay validation was conducted for 5 bacterial strains (TA97, TA98, TA100, TA1535 and TA102) and reproducible exposure–related changes in revertants were observed for TA98 and TA100 in the presence of rat liver S-9 following exposure to 3R4F WS. In the comparative studies, exposure-related changes in in vitro mutagenicity following exposure of TA98 and TA100 in the presence of S9 to both 3R4F and Eclipse WS were observed, with the response for Eclipse being significantly less than that for 3R4F (p < 0.001) which is consistent with the fewer chemical constituents liberated by primarily-heating the product.
Collapse
Affiliation(s)
- Kathy Fowler
- RAI Services Company, Scientific & Regulatory Affairs, 401 North Main Street, Winston-Salem, NC 27101, USA
| | - Wanda Fields
- RAI Services Company, Scientific & Regulatory Affairs, 401 North Main Street, Winston-Salem, NC 27101, USA
| | | | | | - Betsy Bombick
- RAI Services Company, Scientific & Regulatory Affairs, 401 North Main Street, Winston-Salem, NC 27101, USA
| |
Collapse
|
26
|
Choi Y, Park K, Kim I, Kim SD. Combined toxic effect of airborne heavy metals on human lung cell line A549. ENVIRONMENTAL GEOCHEMISTRY AND HEALTH 2018; 40:271-282. [PMID: 27888373 DOI: 10.1007/s10653-016-9901-6] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/26/2016] [Accepted: 11/18/2016] [Indexed: 06/06/2023]
Abstract
Many studies have demonstrated that heavy metals existing as a mixture in the atmospheric environment cause adverse effects on human health and are important key factors of cytotoxicity; however, little investigation has been conducted on a toxicological study of a metal mixture from atmospheric fine particulate matter. The objective of this study was to predict the combined effects of heavy metals in aerosol by using in vitro human cells and obtain a suitable mixture toxicity model. Arsenic, nickel, and lead were selected for mixtures exposed to A549 human lung cancer cells. Cell proliferation (WST-1), glutathione (GSH), and interleukin (IL)-8 inhibition were observed and applied to the prediction models of mixture toxicity, concentration addition (CA) and independent action (IA). The total mixture concentrations were set by an IC10-fixed ratio of individual toxicity to be more realistic for mortality and enzyme inhibition tests. The results showed that the IA model was statistically closer to the observed results than the CA model in mortality, indicating dissimilar modes of action. For the GSH inhibition, the results predicted by the IA and CA models were highly overestimated relative to mortality. Meanwhile, the IL-8 results were stable with no significant change in immune reaction related to inflammation. In conclusion, the IA model is a rapid prediction model in heavy metals mixtures; mortality, as a total outcome of cell response, is a good tool for demonstrating the combined toxicity rather than other biochemical responses.
Collapse
Affiliation(s)
- Yeowool Choi
- School of Earth Sciences and Environmental Engineering, Gwangju Institute of Science and Technology (GIST), 123 Cheomdangwagi-ro, Buk-gu, Gwangju, 61005, Korea
| | - Kihong Park
- School of Earth Sciences and Environmental Engineering, Gwangju Institute of Science and Technology (GIST), 123 Cheomdangwagi-ro, Buk-gu, Gwangju, 61005, Korea
- PM2.5 Research Center, Gwangju Institute of Science and Technology (GIST), 123 Cheomdangwagi-ro, Buk-gu, Gwangju, 61005, Korea
| | - Injeong Kim
- School of Earth Sciences and Environmental Engineering, Gwangju Institute of Science and Technology (GIST), 123 Cheomdangwagi-ro, Buk-gu, Gwangju, 61005, Korea
| | - Sang D Kim
- School of Earth Sciences and Environmental Engineering, Gwangju Institute of Science and Technology (GIST), 123 Cheomdangwagi-ro, Buk-gu, Gwangju, 61005, Korea.
| |
Collapse
|
27
|
Dong TTT, Hinwood AL, Callan AC, Zosky G, Stock WD. In vitro assessment of the toxicity of bushfire emissions: A review. THE SCIENCE OF THE TOTAL ENVIRONMENT 2017; 603-604:268-278. [PMID: 28628818 DOI: 10.1016/j.scitotenv.2017.06.062] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/15/2017] [Revised: 06/05/2017] [Accepted: 06/08/2017] [Indexed: 05/23/2023]
Abstract
Bushfires produce many toxic pollutants and the smoke has been shown to have negative effects on human health, especially to the respiratory system. Bushfires are predicted to increase in size and frequency, leading to a greater incidence of smoke and impacts. While there are many epidemiological studies of the potential impact on populations, there are few studies using in vitro methods to investigate the biological effects of bushfire emissions to better understand its toxicity and significance. This review focused on the literature pertaining to in vitro toxicity testing to determine the state of knowledge on current methods and findings on the impacts of bushfire smoke. There was a considerable variation in the experimental conditions, outcomes and test concentrations used by researchers using in vitro methods. Of the studies reviewed, most reported adverse impacts of particulate matter (PM) on cytotoxic and genotoxic responses. Studies on whole smoke were rare. Finer primary particulates from bushfire smoke were generally found to be more toxic than the coarse particulates and the toxicological endpoints of bushfire PM different to ambient PM. However the variation in study designs and experimental conditions made comparisons difficult. This review highlights the need for standard protocols to enable appropriate comparisons between studies to be undertaken including the assessment of physiologically relevant outcomes. Further work is essential to establish the effect of burning different vegetation types and combustion conditions on the toxicity of bushfire emissions to better inform both health and response agencies on the significance of smoke from bushfires.
Collapse
Affiliation(s)
- Trang T T Dong
- Centre for Ecosystem Management, School of Science, Edith Cowan University, 270 Joondalup Drive, Joondalup, Western Australia 6027, Australia.
| | - Andrea L Hinwood
- Centre for Ecosystem Management, School of Science, Edith Cowan University, 270 Joondalup Drive, Joondalup, Western Australia 6027, Australia
| | - Anna C Callan
- School of Medical and Health Sciences, Edith Cowan University, 270 Joondalup Drive, Joondalup, Western Australia 6027, Australia
| | - Graeme Zosky
- School of Medicine, Faculty of Health, University of Tasmania, 17 Liverpool Street, Hobart, Tasmania 7000, Australia
| | - William D Stock
- Centre for Ecosystem Management, School of Science, Edith Cowan University, 270 Joondalup Drive, Joondalup, Western Australia 6027, Australia
| |
Collapse
|
28
|
Malloy T, Zaunbrecher V, Beryt E, Judson R, Tice R, Allard P, Blake A, Cote I, Godwin H, Heine L, Kerzic P, Kostal J, Marchant G, McPartland J, Moran K, Nel A, Ogunseitan O, Rossi M, Thayer K, Tickner J, Whittaker M, Zarker K. Advancing alternatives analysis: The role of predictive toxicology in selecting safer chemical products and processes. INTEGRATED ENVIRONMENTAL ASSESSMENT AND MANAGEMENT 2017; 13:915-925. [PMID: 28247928 DOI: 10.1002/ieam.1923] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/20/2016] [Revised: 09/26/2016] [Accepted: 02/07/2017] [Indexed: 05/20/2023]
Abstract
Alternatives analysis (AA) is a method used in regulation and product design to identify, assess, and evaluate the safety and viability of potential substitutes for hazardous chemicals. It requires toxicological data for the existing chemical and potential alternatives. Predictive toxicology uses in silico and in vitro approaches, computational models, and other tools to expedite toxicological data generation in a more cost-effective manner than traditional approaches. The present article briefly reviews the challenges associated with using predictive toxicology in regulatory AA, then presents 4 recommendations for its advancement. It recommends using case studies to advance the integration of predictive toxicology into AA, adopting a stepwise process to employing predictive toxicology in AA beginning with prioritization of chemicals of concern, leveraging existing resources to advance the integration of predictive toxicology into the practice of AA, and supporting transdisciplinary efforts. The further incorporation of predictive toxicology into AA would advance the ability of companies and regulators to select alternatives to harmful ingredients, and potentially increase the use of predictive toxicology in regulation more broadly. Integr Environ Assess Manag 2017;13:915-925. © 2017 SETAC.
Collapse
Affiliation(s)
- Timothy Malloy
- School of Law, University of California Los Angeles (UCLA), Los Angeles, California, USA
- Fielding School of Public Health, UCLA, Los Angeles, California, USA
- UC Center for the Environmental Implications of Nanotechnology, UCLA, Los Angeles, California, USA
| | - Virginia Zaunbrecher
- School of Law, University of California Los Angeles (UCLA), Los Angeles, California, USA
- Fielding School of Public Health, UCLA, Los Angeles, California, USA
| | - Elizabeth Beryt
- UC Center for the Environmental Implications of Nanotechnology, UCLA, Los Angeles, California, USA
| | - Richard Judson
- National Center for Computational Toxicology, Research Triangle Park, North Carolina, USA
| | - Raymond Tice
- National Toxicology Program, Durham, North Carolina, USA
| | - Patrick Allard
- Fielding School of Public Health, UCLA, Los Angeles, California, USA
- Institute for Society & Genetics, UCLA, Los Angeles, California, USA
| | - Ann Blake
- Environmental and Public Health Consulting, Alameda, California, USA
| | - Ila Cote
- US Environmental Protection Agency, Washington, DC
| | - Hilary Godwin
- Fielding School of Public Health, UCLA, Los Angeles, California, USA
- UC Center for the Environmental Implications of Nanotechnology, UCLA, Los Angeles, California, USA
| | | | - Patrick Kerzic
- California Department of Toxic Substances Control, Chatsworth, California, USA
| | - Jakub Kostal
- Computational Biology Institute at the George Washington University, Ashburn, Virginia, USA
| | - Gary Marchant
- Sandra Day O'Connor School of Law, Arizona State University, Tempe, Arizona, USA
| | | | - Kelly Moran
- TDC Environmental, San Mateo, California, USA
| | - Andre Nel
- UC Center for the Environmental Implications of Nanotechnology, UCLA, Los Angeles, California, USA
| | - Oladele Ogunseitan
- School of Public Health, University of California Irvine (UCI), Irvine, California, USA
| | - Mark Rossi
- Clean Production Action, Somerville, Massachusetts, USA
| | | | - Joel Tickner
- University of Massachusetts, Lowell, Massachusetts, USA
| | | | - Ken Zarker
- Washington State Department of Ecology, Olympia,, Washington,, USA
| |
Collapse
|
29
|
Khalil C, Shebaby W. UVB damage onset and progression 24 h post exposure in human-derived skin cells. Toxicol Rep 2017; 4:441-449. [PMID: 28959672 PMCID: PMC5615164 DOI: 10.1016/j.toxrep.2017.07.008] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2017] [Revised: 07/21/2017] [Accepted: 07/22/2017] [Indexed: 12/14/2022] Open
Abstract
UVB radiation (280–320 nm) exposure and cellular damages assessment in vitro. Damage progression assessed immediately and 24 h post exposure using cultured human cells with more prominent damages expressed 24 h post exposure. Cytotoxicity assessment investigated mitochondria, lysosomes, cell membrane and, DNA damages. The research reported significant cellular and DNA damages in addition to upregulation and downregulation of various apoptotic proteins.
The focus of this research was on UVB radiation (280–320 nm) responsible for cellular changes in skin of acute and chronically exposed individuals. This study investigated the acute cellular damages triggered by UVB exposure of cultured human fibroblasts and keratinocyte cells immediately and 24 h post exposure in order to understand damage onset and progression. The study evaluated a number of cellular parameters including mitochondria, lysosomes, cell membrane, DNA damages as well as pro and anti-apoptotic protein expression levels. Cellular organelle damages were assessed by a battery of in vitro toxicological assays using MTS and Neutral red cytotoxicity assays. Cell membrane damages were also assessed by measuring lactate dehydrogenase (LDH) enzyme leakage from UVB exposed cells. Lastly DNA damages was assessed using the comet assay while protein expression was evaluated using Western Blot. In this study we reported in all our assay systems (MTS, NR and LDH) that cellular damages were UVB dose dependent with damages amplified 24 h post exposure. Our results also indicated that incubation of exposed cells for a period of 24 h increased the sensitivity of the assay systems used. The increased sensitivity in detecting early cytotoxic damages was manifested though organelle damage measurement at very low doses which were not manifested immediately post exposure. The data also indicated that HaCaT cells were most sensitive in detecting UVB triggered damages immediately and 24 h post exposure using the MTS assay. We also established upregulation and downregulation of various apoptotic proteins at various time points post exposure. The presented data clearly indicated the need for a comprehensive assessment of UVB damages 4 and 24 h post exposure due to the different assay sensitivities in addition to various signaling mechanisms activated at different time points post exposure.
Collapse
Affiliation(s)
- Christian Khalil
- School of Arts and Sciences, Department of Natural Sciences, Lebanese American University (LAU), Byblos, Lebanon.,Institute of Environmental Studies, University of New South Wales (UNSW), Sydney, Australia
| | - Wassim Shebaby
- School of Arts and Sciences, Department of Natural Sciences, Lebanese American University (LAU), Byblos, Lebanon
| |
Collapse
|
30
|
Fields W, Fowler K, Hargreaves V, Reeve L, Bombick B. Development, qualification, validation and application of the neutral red uptake assay in Chinese Hamster Ovary (CHO) cells using a VITROCELL® VC10® smoke exposure system. Toxicol In Vitro 2017; 40:144-152. [PMID: 28062357 DOI: 10.1016/j.tiv.2017.01.001] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2016] [Revised: 12/09/2016] [Accepted: 01/02/2017] [Indexed: 01/29/2023]
Abstract
Cytotoxicity assessment of combustible tobacco products by neutral red uptake (NRU) has historically used total particulate matter (TPM) or solvent captured gas vapor phase (GVP), rather than fresh whole smoke. Here, the development, validation and application of the NRU assay in Chinese Hamster Ovary (CHO) cells, following exposure to fresh whole smoke generated with the VITROCELL® VC10® system is described. Whole smoke exposure is particularly important as both particulate and vapor phases of tobacco smoke show cytotoxicity in vitro. The VITROCELL® VC10® system provides exposure at the air liquid interface (ALI) to mimic in vivo conditions for assessing the toxicological impact of smoke in vitro. Instrument and assay validations are crucial for comparative analyses. GOALS OF THIS STUDY 1) demonstrate functionality of the VITROCELL® VC10® system by installation, operational and performance qualification, 2) develop and validate a cellular system for assessing cytotoxicity following whole smoke exposure and 3) assess the whole smoke NRU assay sensitivity for statistical differentiation between a reference combustible cigarette (3R4F) and a primarily "heat-not-burn" cigarette (Eclipse). RESULTS The VITROCELL® VC10® provided consistent generation and delivery of whole smoke; exposure-related changes in in vitro cytotoxicity were observed with reproducible IC50 values; comparative analysis showed that the heat-not-burn cigarette was significantly (P<0.001) less cytotoxic than the 3R4F combustible cigarette, consistent with the lower levels of chemical constituents liberated by primarily-heating the cigarette versus burning.
Collapse
Affiliation(s)
- Wanda Fields
- RAI Services Company, Scientific & Regulatory Affairs, 401 North Main Street, Winston-Salem, NC 27101, USA.
| | - Kathy Fowler
- RAI Services Company, Scientific & Regulatory Affairs, 401 North Main Street, Winston-Salem, NC 27101, USA
| | - Victoria Hargreaves
- Covance Laboratories Ltd., Otley Road, Harrogate, North Yorkshire HG1 3PY, UK
| | - Lesley Reeve
- Covance Laboratories Ltd., Otley Road, Harrogate, North Yorkshire HG1 3PY, UK
| | - Betsy Bombick
- RAI Services Company, Scientific & Regulatory Affairs, 401 North Main Street, Winston-Salem, NC 27101, USA
| |
Collapse
|
31
|
DeLoid GM, Cohen JM, Pyrgiotakis G, Demokritou P. Preparation, characterization, and in vitro dosimetry of dispersed, engineered nanomaterials. Nat Protoc 2017; 12:355-371. [PMID: 28102836 DOI: 10.1038/nprot.2016.172] [Citation(s) in RCA: 180] [Impact Index Per Article: 25.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Evidence continues to grow of the importance of in vitro and in vivo dosimetry in the hazard assessment and ranking of engineered nanomaterials (ENMs). Accurate dose metrics are particularly important for in vitro cellular screening to assess the potential health risks or bioactivity of ENMs. To ensure meaningful and reproducible quantification of in vitro dose, with consistent measurement and reporting between laboratories, it is necessary to adopt standardized and integrated methodologies for (i) generation of stable ENM suspensions in cell culture media; (ii) colloidal characterization of suspended ENMs, particularly of properties that determine particle kinetics in an in vitro system (size distribution and formed agglomerate effective density); and (iii) robust numerical fate and transport modeling for accurate determination of the ENM dose delivered to cells over the course of the in vitro exposure. Here we present an integrated comprehensive protocol based on such a methodology for in vitro dosimetry, including detailed standardized procedures for each of these three critical aims. The entire protocol requires ∼6-12 h to complete.
Collapse
Affiliation(s)
- Glen M DeLoid
- Center for Nanotechnology and Nanotoxicology, HSPH-NIEHS Nanosafety Research Center, Department of Environmental Health, Harvard School of Public Health, Boston, Massachusetts, USA
| | - Joel M Cohen
- Center for Nanotechnology and Nanotoxicology, HSPH-NIEHS Nanosafety Research Center, Department of Environmental Health, Harvard School of Public Health, Boston, Massachusetts, USA
| | - Georgios Pyrgiotakis
- Center for Nanotechnology and Nanotoxicology, HSPH-NIEHS Nanosafety Research Center, Department of Environmental Health, Harvard School of Public Health, Boston, Massachusetts, USA
| | - Philip Demokritou
- Center for Nanotechnology and Nanotoxicology, HSPH-NIEHS Nanosafety Research Center, Department of Environmental Health, Harvard School of Public Health, Boston, Massachusetts, USA
| |
Collapse
|
32
|
Kastury F, Smith E, Juhasz AL. A critical review of approaches and limitations of inhalation bioavailability and bioaccessibility of metal(loid)s from ambient particulate matter or dust. THE SCIENCE OF THE TOTAL ENVIRONMENT 2017; 574:1054-1074. [PMID: 27672736 DOI: 10.1016/j.scitotenv.2016.09.056] [Citation(s) in RCA: 139] [Impact Index Per Article: 19.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/01/2016] [Revised: 09/06/2016] [Accepted: 09/08/2016] [Indexed: 05/04/2023]
Abstract
Inhalation of metal(loid)s in ambient particulate matter (APM) represents a significant exposure pathway to humans. Although exposure assessment associated with this pathway is currently based on total metal(loid) content, a bioavailability (i.e. absorption in the systemic circulation) and/or bioaccessibility (i.e. solubility in simulated lung fluid) based approach may more accurately quantify exposure. Metal(loid) bioavailability-bioaccessibility assessment from APM is inherently complex and lacks consensus. This paper reviews the discrepancies that impede the adoption of a universal protocol for the assessment of inhalation bioaccessibility. Exposure assessment approaches for in-vivo bioavailability, in-vitro cell culture and in-vitro bioaccessibility (composition of simulated lungs fluid, physico-chemical and methodological considerations) are critiqued in the context of inhalation exposure refinement. An important limitation of bioavailability and bioaccessibility studies is the use of considerably higher than environmental metal(loid) concentration, which diminishing their relevance to human exposure scenarios. Similarly, individual metal(loid) studies have been criticised due to complexities of APM metal(loid) mixtures which may impart synergistic or antagonistic effects compared to single metal(loid) exposure. Although a number of different simulated lung fluid (SLF) compositions have been used in metal(loid) bioaccessibility studies, information regarding the comparative leaching efficiency among these different SLF and comparisons to in-vivo bioavailability data is lacking. In addition, the particle size utilised is often not representative of what is deposited in the lungs while assay parameters (extraction time, solid to liquid ratio, temperature and agitation) are often not biologically relevant. Research needs are identified in order to develop robust in-vitro bioaccessibility protocols for the assessment or prediction of metal(loid) bioavailability in APM for the refinement of inhalation exposure.
Collapse
Affiliation(s)
- Farzana Kastury
- Future Industries Institute, University of South Australia, Mawson Lakes Campus, Adelaide, SA 5095, Australia.
| | - Euan Smith
- Future Industries Institute, University of South Australia, Mawson Lakes Campus, Adelaide, SA 5095, Australia
| | - Albert L Juhasz
- Future Industries Institute, University of South Australia, Mawson Lakes Campus, Adelaide, SA 5095, Australia
| |
Collapse
|
33
|
Steiner S, Bisig C, Petri-Fink A, Rothen-Rutishauser B. Diesel exhaust: current knowledge of adverse effects and underlying cellular mechanisms. Arch Toxicol 2016; 90:1541-53. [PMID: 27165416 PMCID: PMC4894930 DOI: 10.1007/s00204-016-1736-5] [Citation(s) in RCA: 146] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2016] [Accepted: 04/28/2016] [Indexed: 12/03/2022]
Abstract
Diesel engine emissions are among the most prevalent anthropogenic pollutants worldwide, and with the growing popularity of diesel-fueled engines in the private transportation sector, they are becoming increasingly widespread in densely populated urban regions. However, a large number of toxicological studies clearly show that diesel engine emissions profoundly affect human health. Thus the interest in the molecular and cellular mechanisms underlying these effects is large, especially concerning the nature of the components of diesel exhaust responsible for the effects and how they could be eliminated from the exhaust. This review describes the fundamental properties of diesel exhaust as well as the human respiratory tract and concludes that adverse health effects of diesel exhaust not only emerge from its chemical composition, but also from the interplay between its physical properties, the physiological and cellular properties, and function of the human respiratory tract. Furthermore, the primary molecular and cellular mechanisms triggered by diesel exhaust exposure, as well as the fundamentals of the methods for toxicological testing of diesel exhaust toxicity, are described. The key aspects of adverse effects induced by diesel exhaust exposure described herein will be important for regulators to support or ban certain technologies or to legitimate incentives for the development of promising new technologies such as catalytic diesel particle filters.
Collapse
Affiliation(s)
- Sandro Steiner
- Adolphe Merkle Institute, University of Fribourg, Chemin des Verdiers 4, 1700, Fribourg, Switzerland
| | - Christoph Bisig
- Adolphe Merkle Institute, University of Fribourg, Chemin des Verdiers 4, 1700, Fribourg, Switzerland
| | - Alke Petri-Fink
- Adolphe Merkle Institute, University of Fribourg, Chemin des Verdiers 4, 1700, Fribourg, Switzerland
| | | |
Collapse
|
34
|
Hasspieler B, Haffner D, Stelljes M, Adeli K. Toxicological assessment of industrial solvents using human cell bioassays: assessment of short-term cytotoxicity and long-term genotoxicity potential. Toxicol Ind Health 2016; 22:301-15. [PMID: 17022437 DOI: 10.1177/0748233706070312] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
There is an increasing demand for simple toxicological screening methods to assess the human health risk associated with exposure to environmental toxicants. Such screening tools should allow for risk evaluation in terms of both short-term/acute toxicity and longer-term genetic damage, which may lead to mutagenicity and carcinogenicity. We employed a battery of human cell bioassays using the human hepatoma cell-line, HepG2, to assess the cytotoxic and genotoxic potential of environmental pollutants. Here, we demonstrate direct application of these human cell bioassays to the toxicological assessment of a number of industrial solvents that are in common use worldwide. HepG2 cells were exposed to various solvents at concentrations ranging from 25 to 500 ppm. The cells were then analysed using specific protocols for four different adverse effects: cell death/acute cytotoxicity using a neutral red uptake assay, altered enzyme function (often an indicator of cell stress) using the ethoxyresorufin O-deethylase (EROD) bioassay, DNA single strand breaks (SSB), and DNA repair induction, which evaluates mutagenic activity. Using the positive controls, linear dose-response curves were achieved for all four bioassays. The high sensitivity of the tests allowed for environmentally meaningful assessments, and precision studies showed excellent reproducibility for all four bioassays. Comparing the results of the four bioassays on each of 16 industrial solvents allowed for ranking of the anticipated relative human toxicity of these solvents, which were comparable with data from standard toxicity tests and human occupational data. Overall, the study clearly supports the application of the HepG2 cell bioassay system for rapid toxicological screening of many candidate toxicants for both short- and long-term toxicity potential.
Collapse
|
35
|
Toxicological Considerations, Toxicity Assessment, and Risk Management of Inhaled Nanoparticles. Int J Mol Sci 2016; 17:ijms17060929. [PMID: 27314324 PMCID: PMC4926462 DOI: 10.3390/ijms17060929] [Citation(s) in RCA: 102] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2016] [Revised: 05/25/2016] [Accepted: 05/25/2016] [Indexed: 01/18/2023] Open
Abstract
Novel engineered nanoparticles (NPs), nanomaterial (NM) products and composites, are continually emerging worldwide. Many potential benefits are expected from their commercial applications; however, these benefits should always be balanced against risks. Potential toxic effects of NM exposure have been highlighted, but, as there is a lack of understanding about potential interactions of nanomaterials (NMs) with biological systems, these side effects are often ignored. NPs are able to translocate to the bloodstream, cross body membrane barriers effectively, and affect organs and tissues at cellular and molecular levels. NPs may pass the blood–brain barrier (BBB) and gain access to the brain. The interactions of NPs with biological milieu and resulted toxic effects are significantly associated with their small size distribution, large surface area to mass ratio (SA/MR), and surface characteristics. NMs are able to cross tissue and cell membranes, enter into cellular compartments, and cause cellular injury as well as toxicity. The extremely large SA/MR of NPs is also available to undergo reactions. An increased surface area of the identical chemical will increase surface reactivity, adsorption properties, and potential toxicity. This review explores biological pathways of NPs, their toxic potential, and underlying mechanisms responsible for such toxic effects. The necessity of toxicological risk assessment to human health should be emphasised as an integral part of NM design and manufacture.
Collapse
|
36
|
Nguta JM, Appiah-Opong R, Nyarko AK, Yeboah-Manu D, Addo PGA, Otchere I, Kissi-Twum A. Antimycobacterial and cytotoxic activity of selected medicinal plant extracts. JOURNAL OF ETHNOPHARMACOLOGY 2016; 182:10-5. [PMID: 26875647 PMCID: PMC4801013 DOI: 10.1016/j.jep.2016.02.010] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/04/2015] [Revised: 02/03/2016] [Accepted: 02/09/2016] [Indexed: 05/08/2023]
Abstract
ETHNOPHARMACOLOGICAL RELEVANCE Tuberculosis (TB) caused by Mycobacterium tuberculosis remains an ongoing threat to human health. Several medicinal plants are used traditionally to treat tuberculosis in Ghana. The current study was designed to investigate the antimycobacterial activity and cytotoxicity of crude extracts from five selected medicinal plants. MATERIAL AND METHODS The microplate alamar blue assay (MABA) was used for antimycobacterial studies while the CellTiter 96® AQueous Assay, which is composed of solutions of a novel tetrazolium compound [3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium, inner salt; MTS] and an electron coupling reagent (phenazine methosulfate) PMS, was used for cytotoxic studies. Correlation coefficients were used to compare the activity of crude extracts against nonpathogenic strains and the pathogenic Mycobacterium tuberculosis subsp.tuberculosis. RESULTS Results of the MIC determinations indicated that all the crude extracts were active on all the three tested mycobacterial strains. Minimum inhibitory concentration values as low as 156.3µg/mL against M. tuberculosis; Strain H37Ra (ATCC® 25,177™) were recorded from the leaves of Solanum torvum Sw. (Solanaceae). Cytotoxicity of the extracts varied, and the leaves from S. torvum had the most promising selectivity index. Activity against M. tuberculosis; Strain H37Ra was the best predictor of activity against pathogenic Mycobacterium tuberculosis subsp.tuberculosis (correlation coefficient=0.8). CONCLUSION The overall results of the present study provide supportive data on the use of some medicinal plants for tuberculosis treatment. The leaves of Solanum torvum are a potential source of anti-TB natural products and deserve further investigations to develop novel anti-TB agents against sensitive and drug resistant strains of M. tuberculosis.
Collapse
Affiliation(s)
- Joseph M Nguta
- Department of Clinical Pathology, Noguchi Memorial Institute for Medical Research, University of Ghana, Ghana; Department of Public Health, Pharmacology and Toxicology, Faculty of Veterinary Medicine, University of Nairobi, Kenya
| | - Regina Appiah-Opong
- Department of Clinical Pathology, Noguchi Memorial Institute for Medical Research, University of Ghana, Ghana
| | - Alexander K Nyarko
- Department of Clinical Pathology, Noguchi Memorial Institute for Medical Research, University of Ghana, Ghana
| | - Dorothy Yeboah-Manu
- Department of Bacteriology, Noguchi Memorial Institute for Medical Research, University of Ghana, Ghana
| | - Phyllis G A Addo
- Department of Animal Experimentation, Noguchi Memorial Institute for Medical Research, University of Ghana, Ghana
| | - Isaac Otchere
- Department of Bacteriology, Noguchi Memorial Institute for Medical Research, University of Ghana, Ghana
| | - Abena Kissi-Twum
- Department of Clinical Pathology, Noguchi Memorial Institute for Medical Research, University of Ghana, Ghana
| |
Collapse
|
37
|
Nguta JM, Appiah-Opong R, Nyarko AK, Yeboah-Manu D, Addo PG, Otchere ID, Kissi-Twum A. In vitro antimycobacterial and cytotoxic data on medicinal plants used to treat tuberculosis. Data Brief 2016; 7:1124-30. [PMID: 27115026 PMCID: PMC4833128 DOI: 10.1016/j.dib.2016.03.088] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2016] [Revised: 03/09/2016] [Accepted: 03/26/2016] [Indexed: 11/26/2022] Open
Abstract
This article contains data on in vitro antimycobacterial activity and cytotoxicity of hydroethanolic crude extracts from five selected medicinal plant species traditionally used to treat tuberculosis in Ghanaian ethnomedicine, see “Medicinal plants used to treat TB in Ghana” [1]. The interpretation and discussion of these data and further extensive insights into drug discovery against tuberculosis from natural products of plant biodiversity can be found in “Antimycobacterial and cytotoxic activity of selected medicinal plant extracts” [2].
Collapse
Affiliation(s)
- Joseph M. Nguta
- Department of Clinical Pathology, Noguchi Memorial Institute for Medical Research, University of Ghana, Ghana
- Department of Public Health, Pharmacology and Toxicology, Faculty of Veterinary Medicine, University of Nairobi, Kenya
- Corresponding author.
| | - Regina Appiah-Opong
- Department of Clinical Pathology, Noguchi Memorial Institute for Medical Research, University of Ghana, Ghana
| | - Alexander K. Nyarko
- Department of Clinical Pathology, Noguchi Memorial Institute for Medical Research, University of Ghana, Ghana
| | - Dorothy Yeboah-Manu
- Department of Bacteriology, Noguchi Memorial Institute for Medical Research, University of Ghana, Ghana
| | - Phyllis G.A. Addo
- Department of Animal Experimentation, Noguchi Memorial Institute for Medical Research, University of Ghana, Ghana
| | - Isaac D. Otchere
- Department of Bacteriology, Noguchi Memorial Institute for Medical Research, University of Ghana, Ghana
| | - Abena Kissi-Twum
- Department of Clinical Pathology, Noguchi Memorial Institute for Medical Research, University of Ghana, Ghana
| |
Collapse
|
38
|
Wiemann M, Vennemann A, Sauer UG, Wiench K, Ma-Hock L, Landsiedel R. An in vitro alveolar macrophage assay for predicting the short-term inhalation toxicity of nanomaterials. J Nanobiotechnology 2016; 14:16. [PMID: 26944705 PMCID: PMC4779246 DOI: 10.1186/s12951-016-0164-2] [Citation(s) in RCA: 88] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2016] [Accepted: 02/10/2016] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Most in vitro studies investigating nanomaterial pulmonary toxicity poorly correlate to in vivo inhalation studies. Alveolar macrophages (AMs) play an outstanding role during inhalation exposure since they effectively clear the alveoli from particles. This study addresses the applicability of an in vitro alveolar macrophage assay to distinguish biologically active from passive nanomaterials. METHODS Rat NR8383 alveolar macrophages were exposed to 18 inorganic nanomaterials, covering AlOOH, BaSO4, CeO2, Fe2O3, TiO2, ZrO2, and ZnO NMs, amorphous SiO2 and graphite nanoplatelets, and two nanosized organic pigments. ZrO2 and amorphous SiO2 were tested without and with surface functionalization. Non-nanosized quartz DQ12 and corundum were used as positive and negative controls, respectively. The test materials were incubated with the cells in protein-free culture medium. Lactate dehydrogenase, glucuronidase, and tumour necrosis factor alpha were assessed after 16 h. In parallel, H2O2 was assessed after 1.5 h. Using the no-observed-adverse-effect concentrations (NOAECs) from available rat short-term inhalation studies (STIS), the test materials were categorized as active (NOAEC < 10 mg/m(3)) or passive. RESULTS In vitro data reflected the STIS categorization if a particle surface area-based threshold of <6000 mm(2)/mL was used to determine the biological relevance of the lowest observed significant in vitro effects. Significant effects that were recorded above this threshold were assessed as resulting from test material-unspecific cellular 'overload'. Test materials were assessed as active if ≥2 of the 4 in vitro parameters undercut this threshold. They were assessed as passive if 0 or 1 parameter was altered. An overall assay accuracy of 95 % was achieved. CONCLUSIONS The in vitro NR8383 alveolar macrophage assay allows distinguishing active from passive nanomaterials. Thereby, it allows determining whether in vivo short-term inhalation testing is necessary for hazard assessment. Results may also be used to group nanomaterials by biological activity. Further work should aim at validating the assay.
Collapse
Affiliation(s)
- Martin Wiemann
- IBR R&D gGmbH Institute for Lung Health, Mendelstraße 11, 48149, Münster, Germany.
| | - Antje Vennemann
- IBR R&D gGmbH Institute for Lung Health, Mendelstraße 11, 48149, Münster, Germany.
| | - Ursula G Sauer
- Scientific Consultancy - Animal Welfare, Hallstattfeld 16, 85579, Neubiberg, Germany.
| | - Karin Wiench
- BASF SE, Experimental Toxicology and Ecology, GB/TB - Z470, 67056, Ludwigshafen, Germany.
| | - Lan Ma-Hock
- BASF SE, Experimental Toxicology and Ecology, GB/TB - Z470, 67056, Ludwigshafen, Germany.
| | - Robert Landsiedel
- BASF SE, Experimental Toxicology and Ecology, GB/TB - Z470, 67056, Ludwigshafen, Germany.
| |
Collapse
|
39
|
Khalil C. In Vitro UVB induced Cellular Damage Assessment Using Primary Human Skin Derived Fibroblasts. ACTA ACUST UNITED AC 2015. [DOI: 10.15406/mojt.2015.01.00020] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
|
40
|
A comparison of three dispersion media on the physicochemical and toxicological behavior of TiO2 and NiO nanoparticles. Chem Biol Interact 2015; 236:74-81. [PMID: 25964212 DOI: 10.1016/j.cbi.2015.05.001] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2014] [Revised: 04/15/2015] [Accepted: 05/04/2015] [Indexed: 11/20/2022]
Abstract
UNLABELLED Nanomaterials represent a burgeoning field of technological innovation. With the onset of environmental release and commercial product exposure associated with nanomaterial manufacture and proliferation, the concomitant effects on human health remain unknown and demand further investigation. Agglomeration of nanomaterials in biologically relevant media used in in vitro methods further complicates dosing in toxicological study. OBJECTIVE to compare the effects of in vitro dispersion techniques on the physicochemical and toxicological dosimetry of TiO2 (<50 nm) and NiO (<20 nm) nanoparticles and some resulting toxicological endpoints to test for potential effects. METHODS three media were prepared for A549 and 16hbe14o cells with varying concentrations of TiO2 and NiO nanoparticles. Physicochemical effects were analyzed with dynamic light scattering, ICP-MS, SEM, and TEM. Toxicological effects were determined after stimulation of cells with nanoparticles for 4 and 24h followed by analysis of inflammatory and oxidative stress markers with ELISA and RT-PCR. Our data show that dispersion media differentially affect physicochemical properties and toxicological endpoints. Therefore, we conclude that in vitro nanotoxicology models that use re-suspension methods of exposure yield inconsistent and misleading biological results due to physicochemical variation of particle characteristics and transport processes.
Collapse
|
41
|
The history, genotoxicity, and carcinogenicity of carbon-based fuels and their emissions: 1. Principles and background. MUTATION RESEARCH-REVIEWS IN MUTATION RESEARCH 2014; 762:76-107. [DOI: 10.1016/j.mrrev.2014.07.001] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/07/2014] [Revised: 07/17/2014] [Accepted: 07/20/2014] [Indexed: 12/30/2022]
|
42
|
Breheny D, Cunningham F, Kilford J, Payne R, Dillon D, Meredith C. Application of a modified gaseous exposure system to the in vitro toxicological assessment of tobacco smoke toxicants. ENVIRONMENTAL AND MOLECULAR MUTAGENESIS 2014; 55:662-72. [PMID: 24889675 PMCID: PMC6710645 DOI: 10.1002/em.21876] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/12/2013] [Revised: 05/05/2014] [Accepted: 05/12/2014] [Indexed: 06/03/2023]
Abstract
Tobacco smoke is a complex mixture of over 6,000 individual chemical constituents. Approximately 150 of these have been identified as 'tobacco smoke toxicants' due to their known toxicological effects. A number of these toxicants are present in the gaseous phase of tobacco smoke. This presents a technical challenge when assessing the toxicological effects of these chemicals in vitro. We have adapted a commercially available tobacco smoke exposure system to enable the assessment of the contribution of individual smoke toxicants to the overall toxicological effects of whole mainstream cigarette smoke (WS). Here we present a description of the exposure system and the methodology used. We use the example of a gaseous tobacco smoke toxicant, ethylene oxide (EtO), a Group 1 IARC carcinogen and known mutagen, to illustrate how this methodology can be applied to the assessment of genotoxicity of gaseous chemicals in the context of WS. In the present study we found that EtO was positive in Salmonella typhimurium strain YG1042, a strain that is sensitive to tobacco smoke. However, EtO did not increase the mutagenicity of the WS mixture when it was added at greatly higher concentrations than those found typically in WS. The findings presented here demonstrate the suitability of this exposure system for the assessment of the mutagenic potential of gases in vitro. Whilst we have focused on tobacco smoke toxicants, this system has broad application potential in studying the biological effects of exposure to a wide range of gaseous compounds that are present within complex aerosol mixtures.
Collapse
Affiliation(s)
- Damien Breheny
- British American TobaccoGroup R&D, SouthamptonHampshireSO15 8TLUnited Kingdom
| | - Fiona Cunningham
- British American TobaccoGroup R&D, SouthamptonHampshireSO15 8TLUnited Kingdom
| | - Joanne Kilford
- Covance Laboratories LtdOtley Road, HarrogateNorth YorkshireHG3 1PYUnited Kingdom
| | - Rebecca Payne
- Covance Laboratories LtdOtley Road, HarrogateNorth YorkshireHG3 1PYUnited Kingdom
| | - Deborah Dillon
- British American TobaccoGroup R&D, SouthamptonHampshireSO15 8TLUnited Kingdom
| | - Clive Meredith
- British American TobaccoGroup R&D, SouthamptonHampshireSO15 8TLUnited Kingdom
| |
Collapse
|
43
|
Thorne D, Kilford J, Payne R, Haswell L, Dalrymple A, Meredith C, Dillon D. Development of a BALB/c 3T3 neutral red uptake cytotoxicity test using a mainstream cigarette smoke exposure system. BMC Res Notes 2014; 7:367. [PMID: 24935030 PMCID: PMC4067082 DOI: 10.1186/1756-0500-7-367] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2013] [Accepted: 06/12/2014] [Indexed: 11/29/2022] Open
Abstract
BACKGROUND Tobacco smoke toxicity has traditionally been assessed using the particulate fraction under submerged culture conditions which omits the vapour phase elements from any subsequent analysis. Therefore, methodologies that assess the full interactions and complexities of tobacco smoke are required. Here we describe the adaption of a modified BALB/c 3T3 neutral red uptake (NRU) cytotoxicity test methodology, which is based on the Interagency Coordinating Committee on the Validation of Alternative Methods (ICCVAM) protocol for in vitro acute toxicity testing. The methodology described takes into account the synergies of both the particulate and vapour phase of tobacco smoke. This is of particular importance as both phases have been independently shown to induce in vitro cellular cytotoxicity. FINDINGS The findings from this study indicate that mainstream tobacco smoke and the gas vapour phase (GVP), generated using the Vitrocell® VC 10 smoke exposure system, have distinct and significantly different toxicity profiles. Within the system tested, mainstream tobacco smoke produced a dilution IC50 (dilution (L/min) at which 50% cytotoxicity is observed) of 6.02 L/min, whereas the GVP produced a dilution IC50 of 3.20 L/min. In addition, we also demonstrated significant dose-for-dose differences between mainstream cigarette smoke and the GVP fraction (P < 0.05). This demonstrates the importance of testing the entire tobacco smoke aerosol and not just the particulate fraction, as has been the historical preference. CONCLUSIONS We have adapted the NRU methodology based on the ICCVAM protocol to capture the full interactions and complexities of tobacco smoke. This methodology could also be used to assess the performance of traditional cigarettes, blend and filter technologies, tobacco smoke fractions and individual test aerosols.
Collapse
Affiliation(s)
- David Thorne
- British American Tobacco, Group R&D, Southampton, Hampshire SO15 8TL, UK
| | - Joanne Kilford
- Covance Laboratories Ltd, Otley Road, Harrogate, North Yorkshire HG3 1PY, UK
| | - Rebecca Payne
- Covance Laboratories Ltd, Otley Road, Harrogate, North Yorkshire HG3 1PY, UK
| | - Linsey Haswell
- British American Tobacco, Group R&D, Southampton, Hampshire SO15 8TL, UK
| | - Annette Dalrymple
- British American Tobacco, Group R&D, Southampton, Hampshire SO15 8TL, UK
| | - Clive Meredith
- British American Tobacco, Group R&D, Southampton, Hampshire SO15 8TL, UK
| | - Deborah Dillon
- British American Tobacco, Group R&D, Southampton, Hampshire SO15 8TL, UK
| |
Collapse
|
44
|
Hayes AJ, Bakand S. Toxicological perspectives of inhaled therapeutics and nanoparticles. Expert Opin Drug Metab Toxicol 2014; 10:933-47. [PMID: 24810077 DOI: 10.1517/17425255.2014.916276] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
INTRODUCTION The human respiratory system is an important route for the entry of inhaled therapeutics into the body to treat diseases. Inhaled materials may consist of gases, vapours, aerosols and particulates. In all cases, assessing the toxicological effect of inhaled therapeutics has many challenges. AREAS COVERED This article provides an overview of in vivo and in vitro models for testing the toxicity of inhaled therapeutics and nanoparticles implemented in drug delivery. Traditionally, inhalation toxicity has been performed on test animals to identify the median lethal concentration of airborne materials. Later maximum tolerable concentration denoted by LC0 has been introduced as a more ethically acceptable end point. More recently, in vitro methods have been developed, allowing the direct exposure of airborne material to cultured human target cells on permeable porous membranes at the air-liquid interface. EXPERT OPINION Modifications of current inhalation therapies, new pulmonary medications for respiratory diseases and implementation of the respiratory tract for systemic drug delivery are providing new challenges when conducting well-designed inhalation toxicology studies. In particular, the area of nanoparticles and nanocarriers is of critical toxicological concern. There is a need to develop toxicological test models, which characterise the toxic response and cellular interaction between inhaled particles and the respiratory system.
Collapse
Affiliation(s)
- Amanda J Hayes
- The University of New South Wales, School of Chemistry , UNSW Sydney, 2052 , Australia +61 403 028747 ; +61 2 9385 6141 ;
| | | |
Collapse
|
45
|
Methods for Assessing Basic Particle Properties and Cytotoxicity of Engineered Nanoparticles. TOXICS 2014. [DOI: 10.3390/toxics2010079] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
|
46
|
Anderson SE, Khurshid SS, Meade BJ, Lukomska E, Wells JR. Toxicological analysis of limonene reaction products using an in vitro exposure system. Toxicol In Vitro 2013; 27:721-30. [PMID: 23220291 PMCID: PMC4680979 DOI: 10.1016/j.tiv.2012.11.017] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2012] [Revised: 11/23/2012] [Accepted: 11/28/2012] [Indexed: 11/30/2022]
Abstract
Epidemiological investigations suggest a link between exposure to indoor air chemicals and adverse health effects. Consumer products contain reactive chemicals which can form secondary pollutants which may contribute to these effects. The reaction of limonene and ozone is a well characterized example of this type of indoor air chemistry. The studies described here characterize an in vitro model using an epithelial cell line (A549) or differentiated epithelial tissue (MucilAir™). The model is used to investigate adverse effects following exposure to combinations of limonene and ozone. In A549 cells, exposure to both the parent compounds and reaction products resulted in alterations in inflammatory cytokine production. A one hour exposure to limonene+ozone resulted in decreased proliferation when compared to cells exposed to limonene alone. Repeated dose exposures of limonene or limonene+ozone were conducted on MucilAir™ tissue. No change in proliferation was observed but increases in cytokine production were observed for both the parent compounds and reaction products. Factors such as exposure duration, chemical concentration, and sampling time point were identified to influence result outcome. These findings suggest that exposure to reaction products may produce more severe effects compared to the parent compound.
Collapse
Affiliation(s)
- Stacey E Anderson
- Health Effects Laboratory Division, National Institute for Occupational Safety and Health, Morgantown, WV, United States.
| | | | | | | | | |
Collapse
|
47
|
Crooks I, Dillon DM, Scott JK, Ballantyne M, Meredith C. The effect of long term storage on tobacco smoke particulate matter in in vitro genotoxicity and cytotoxicity assays. Regul Toxicol Pharmacol 2013; 65:196-200. [PMID: 23220485 DOI: 10.1016/j.yrtph.2012.11.012] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2012] [Revised: 11/23/2012] [Accepted: 11/28/2012] [Indexed: 11/30/2022]
Abstract
Particulate matter (PM) collected from mainstream tobacco smoke is a test article commonly used for in vitro genotoxicity and cytotoxicity testing of combustible tobacco products. However, little published data exists concerning the stability of PM. We completed a 2 year study to quantify the effect of PM storage at -80 °C, on the genotoxicity and cytotoxicity of PM generated from 3R4F and M4A reference cigarettes. The Ames test, Micronucleus assay (MNvit), Mouse Lymphoma assay (MLA) and the Neutral Red Uptake assay (NRU) were used. The majority of M4A and 3R4F PMs were genotoxic and cytotoxic at the timepoints tested. Some minor but statistically significant differences were observed for stored versus freshly prepared PM, but the magnitude of changes were within the variability observed for repeat testing.
Collapse
Affiliation(s)
- I Crooks
- British American Tobacco, Group Research and Development, Regents Park Road, Southampton, Hampshire, SO15 8TL, United Kingdom.
| | | | | | | | | |
Collapse
|
48
|
Sauer UG, Vogel S, Hess A, Kolle SN, Ma-Hock L, van Ravenzwaay B, Landsiedel R. In vivo–in vitro comparison of acute respiratory tract toxicity using human 3D airway epithelial models and human A549 and murine 3T3 monolayer cell systems. Toxicol In Vitro 2013; 27:174-90. [DOI: 10.1016/j.tiv.2012.10.007] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2012] [Revised: 10/04/2012] [Accepted: 10/11/2012] [Indexed: 10/27/2022]
|
49
|
Spencer P, Fry RC, Kisby GE. Unraveling 50-Year-Old Clues Linking Neurodegeneration and Cancer to Cycad Toxins: Are microRNAs Common Mediators? Front Genet 2012; 3:192. [PMID: 23060898 PMCID: PMC3460211 DOI: 10.3389/fgene.2012.00192] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2012] [Accepted: 09/09/2012] [Indexed: 01/19/2023] Open
Abstract
Recognition of overlapping molecular signaling activated by a chemical trigger of cancer and neurodegeneration is new, but the path to this discovery has been long and potholed. Six conferences (1962–1972) examined the puzzling neurotoxic and carcinogenic properties of a then-novel toxin [cycasin: methylazoxymethanol (MAM)-β-d-glucoside] in cycad plants used traditionally for food and medicine on Guam where a complex neurodegenerative disease plagued the indigenous population. Affected families showed combinations of amyotrophic lateral sclerosis (ALS), parkinsonism (P), and/or a dementia (D) akin to Alzheimer’s disease (AD). Modernization saw declining disease rates on Guam and remarkable changes in clinical phenotype (ALS was replaced by P-D and then by D) and in two genetically distinct ALS-PDC-affected populations (Kii-Japan, West Papua-Indonesia) that used cycad seed medicinally. MAM forms DNA lesions – repaired by O6-methylguanine methyltransferase (MGMT) – that perturb mouse brain development and induce malignant tumors in peripheral organs. The brains of young adult MGMT-deficient mice given a single dose of MAM show DNA lesion-linked changes in cell-signaling pathways associated with miRNA-1, which is implicated in colon, liver, and prostate cancers, and in neurological disease, notably AD. MAM is metabolized to formaldehyde, a human carcinogen. Formaldehyde-responsive miRNAs predicted to modulate MAM-associated genes in the brains of MGMT-deficient mice include miR-17-5p and miR-18d, which regulate genes involved in tumor suppression, DNA repair, amyloid deposition, and neurotransmission. These findings marry cycad-associated ALS-PDC with colon, liver, and prostate cancer; they also add to evidence linking changes in microRNA status both to ALS, AD, and parkinsonism, and to cancer initiation and progression.
Collapse
Affiliation(s)
- Peter Spencer
- Global Health Center, Oregon Health and Science University Portland, OR, USA
| | | | | |
Collapse
|
50
|
In vitro cytotoxicity and morphological assessment of smoke from polymer combustion in human lung derived cells (A549). Int J Hyg Environ Health 2012; 215:320-32. [DOI: 10.1016/j.ijheh.2011.12.006] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2010] [Revised: 12/01/2011] [Accepted: 12/17/2011] [Indexed: 11/20/2022]
|