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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Physician Readiness for Nurse Practitioners in the Emergency Department

McGee, Angela Ann, McGee, Angela Ann January 2017 (has links)
Background: Emergency Department (ED) overcrowding is a national healthcare problem, and despite awareness and efforts to alleviate excessive patient volume, it continues to be an epidemic. One improvement technique proposed is to increase employment of independently licensed APRNs in the ED. Objective: The objective of this study was to determine if LMC and USACS physicians are willing and ready to implement and collaborate with NPs in the ED. Design and Methods: A non-experimental descriptive study design was employed, and sixty emergency medicine providers were surveyed. Eighteen participants (14 MDs, 4 DOs) completed an online questionnaire which consisted of 21 Likert-style questions, an open-ended question, and six demographic questions. Research questions: 1) What are physician perceptions regarding the tasks and resources required for NPs to practice in emergency medicine? 2) What are physician perceptions regarding the need, importance, and benefits of NPs in the ED? 3) What are physician perceptions of contextual factors regarding NPs’ working in the organization? Results: Entire Questionnaire: Mean = 2.02 (SD = .35); Subscale 1: Mean = 2.13 (SD = .33); Subscale 2: Mean = 1.79 (SD = .48); Subscale 3: Mean = 2.06 (SD = .49). Conclusion: This study concludes that, overall, there is a readiness to change among the USACS physicians. Evaluation of subscale 2 and 3 from this study indicates that USACS physicians are willing and ready to implement an NP service in LMC's ED. Furthermore, while discrepancies occurred in subscale 1, these differences can be mitigated through education, credentialing requirements, and policy development.
12

The Assessment of Effects of Carbon Quantum Dots on Immune System Biomarkers Using RAW 264.7 Macrophage Cells

Fowler, Jodi January 2020 (has links)
>Magister Scientiae - MSc / Nanotechnology is a rapidly growing field of research. Due to major innovations brought about by developments in nanotech, several consumer products are currently available containing nanomaterials. The increase of nanomaterial production and use is accompanied by the increased potential of human, plant and animal exposure to these nanomaterials. As a relatively new nanomaterial, carbon quantum dots (CQDs) are being extensively used and researched due to its unique properties. Although many studies have assessed the toxic potential of CQDs, and found them to exhibit low toxicity, there is lack of work assessing the effects on the immune system. In the present study, RAW 264.7 murine macrophages were used as model to assess the immunomodulatory potential of CQDs. RAW cells exposed to varying concentrations of CQDs (0-500μg/ml), showed that CQDs caused a reduction at cell viability. In the absence of a mitogen CQDs, induced an inflammatory response by stimulating the release of various cytokines and chemokines such as, TNFα, MIP-1α, MIP-1β, MIP-2, IP-10, G-CSF, GM-CSF, and JE.
13

Synthesis and analysis of potential metabolites of ADB-5´Br-BUTINACA

Malekshahineia, Alaa January 2023 (has links)
In recent years, there has been a rise in the use of New Psychoactive Substances (NPS) that mimic the effects of controlled drugs and licensed medicines, which have become a significant public health concern globally. Synthetic cannabinoids, a rapidly expanding category of NPS, with much higher potency and binding affinity to the cannabinoid receptors than ∆9-tetrahydrocannabinol (THC), have led to serious psychiatric complications and other adverse effects. This project aims to synthesize and analyze four potential metabolites of a synthetic cannabinoid, ADB-5´Br-BUTINACA, to determine if the synthesized metabolites correspond to those produced in human hepatocytes. The metabolites were synthesized by alkylation, amide coupling, and hydrolysis/TFA treatment and analyzed using high-performance liquid chromatography-mass spectrometry (HPLC-MS) and nuclear magnetic resonance (NMR). The reaction strategy combined all three steps into a single process, making it significantly easier to carry out and not requiring much expertise. The results suggest that the synthetic approach used in this project was successful in generating the desired potential metabolites, with overall yields varying from 27.5 % to 57.6 % and high purities ranging from 95.6 % to 99.3 %. However, the overall yields were lower than expected due to product loss during the transfer of the solution mixture, the possibility of side reactions, and incomplete conversion. Further optimization of reaction conditions may be necessary to improve the yield of the synthesized metabolites.
14

Predicting Sediment Detachment and Channel Scour in the Process-Based Planning Model ANSWERS-2000

Byne, Frank Wesley 05 May 2000 (has links)
ANSWERS-2000, a continuous simulation, distributed parameter nonpoint source model for simulating runoff, sediment, and nutrients from disturbed watersheds was updated to include a critical-shear rill detachment subroutine, an improved interrill detachment subroutine, and a channel scour subroutine. The existing version of ANSWERS-2000 did not simulate channel scour. The original detachment equations used in the model were developed through regression analysis of data from a northeast Indiana watershed, and were not directly applicable to other watersheds. The new detachment equations are based on process-oriented equations developed for the WEPP model and they can be applied to ungaged watersheds with a wide variety of soils and land use conditions. The new model (ANSWERS-2000) was evaluated on three watersheds and its predictions were compared with the previous version of ANSWERS. On the largest watershed (2070 hectares), both models appeared to predict sediment loss adequately. On the second watershed (1053 hectares), ANSWERS-2000 improved sediment yield predictions compared to the original model. Neither model adequately described sediment loss from the smallest watershed (1.2 ha) used for validation. The sediment prediction errors were caused by errors in runoff prediction, despite an attempt to increase runoff prediction accuracy by calibration. The channel scour subroutine was evaluated by comparison with observed channel erosion data from the largest watershed. The new model appeared to consistently over predict scoured depth. However, more research is required to determine if the channel scour component is flawed or if the uncertainty in the observed channel scour data was large as suspected. Ultimately, the erosion prediction accuracy of the ANSWERS-2000 model was improved in two of the three upland evaluation data sets. The channel scour data set was not successfully validated. Model input parameter requirements increased significantly as a result of the new erosion and channel scour submodels. / Master of Science
15

Risk assessment formulation for nitrate leaching

Carter, E. Thomas Jr. 18 November 2008 (has links)
A framework for evaluating the risk of water pollution from the application of liquid dairy manure to agricultural fields was developed and applied. The GLEAMS (Groundwater Loading Effects of Agricultural Management Practices) (Ver 2.1) model was used to simulate NO₃-N leaching below the root zone for different land application rates of liquid dairy waste for fields in Georgia and Texas. Probability distributions of yearly-maximum nitrate concentrations were developed for each application rate at each site using the simulated nitrate concentrations. The probability of failure (exceeding 10 mg/L NO₃-N) for each application rate was determined from its corresponding distribution. An appropriate fine for farmers based on probability of failure for different land application rates was determined through economic analysis. The expected risk to farmers in monetary terms was determined for each application rate based on possible fines and the probability of failure. The monetary risk of nitrate leaching to ground water was compared to the social value of ground water. The probability of failure for liquid dairy waste application rates between 200 to 800 kg·N/ha/yr ranged from 0.0022 to 0.74 for Tifton, GA. The probability of failure for liquid dairy waste application rates between 0 and 1000 kg·N/ha/yr ranged from 0.00 to 0.85 for Overton, TX. The maximum application rate that was environmentally acceptable for both Texas and Georgia was 250 kg·N/ha/yr based on the probability of failure. Fines of $1100/ha and $700/ha for the Georgia and Texas sites, respectively, would provide farmers with economic incentives not to exceed an application rate of 250 kg·N/ha/yr. These fines resulted in risks to farmers of $814/ha in Georgia for 800 kg·N/ha/yr application rate and $595/ha in Texas for 1000 kg·N/ha/yr rate. This compares with a social value ranging from $860/ha to $1432/ha of clean ground water. / Master of Science
16

A mathematical model of the nitrogen cycle in a constructed wetland

Widener, Andrew Scott 17 December 2008 (has links)
A model was developed using contemporary wetland theory to predict the fate of nitrogen runoff in a constructed wetland. The model utilizes nitrogen concentrations of influent water as system inputs. The model is three-dimensional, one dimensional in time, and two dimensional in space. The physical domain of the model incorporates a flat emergent marsh and deep pool and includes the water body and underlying sediment. Solutions for concentration of sediment-bound organic nitrogen are obtained for the water body and the sediment-water interface, while solutions for concentration of ammonium and nitrate are obtained for the entire physical domain. Physical conditions are considered along the system boundaries, and a jump condition is modeled for nutrient diffusion through the sediment-water interface. A hyperbolic advection-settling equation models the transport and deposition of sediment-bound organic nitrogen; mineralization of deposited nitrogen is modeled. A parabolic advection-diffusion equation is used to model the movement of dissolved ammonium and nitrate through the wetland water body; the equation is modified for both ammonium and nitrate to model diffusion and transformation in the sediment layer. Spatial variation of sediment layer aerobic and anaerobic regions is considered, as are temperature and pH effects on transformation rates. Numerical solutions are obtained using divided differences. Constructed wetlands for use in NPS pollution control are a new concept; there is no data currently available to use for model validation. The model was shown to be consistent with qualitative theoretical considerations, based on simulations of different scenarios. / Master of Science
17

Designer benzodiazepines gidazepam and desalkygidazepam (bromonordiazepam): What do we know?

Maskell, P.D., Wilson, G., Manchester, Kieran R. 26 January 2023 (has links)
Yes / Designer benzodiazepines are one of the primary new psychoactive substances (NPS) threats around the world, being found in large numbers in post-mortem, driving under the influence of drugs (DUID) and drug facilitated sexual assault (DFSA) cases. Even though when compared to many other NPS types, such as opioids and cathinones, there are relatively few designer benzodiazepines being monitored. Recently a new NPS benzodiazepine has been reported in Europe, the USA and Canada, desalkygidazepam, also known as bromonordiazepam. This substance is a metabolite of the pro-drug gidazepam, a drug licenced for use in Ukraine and Russia under the name Gidazepam IC®. In the paper we review what is currently known about the use, pharmacology and analytical detection of gidazepam, its metabolite desalkygidazepam, and their other possible metabolites.
18

Síntese e caracterização de nanopartículas Fe3O4@Au e desenvolvimento de sensores para aplicações em nanomedicina / Synthesis and characterization of Fe3O4@Au nanoparticles and development of sensors for application in nanomedicine

Ballesteros, Camilo Arturo Suarez 31 July 2012 (has links)
Com o desenvolvimento de novos nanomateriais têm-se descoberto propriedades eletrônicas, elétricas, ópticas e catalíticas únicas para aplicações nanotecnológicas. Entre estes nanomateriais com caraterísticas singulares, estão as nanopartículas (Np) CoreαShell, as quais combinam propriedades físico-químicas de dois materiais diferentes, provendo maior eficiência em aplicações como nanoeletrônica, sensoreamento, biossensoreamento e biomédicas. Neste trabalho, Np CoreαShell são sintetizada com núcleo (Core) de Np Fe₃O₄ e com casca (Shell) de Np Au, formando as Nps Fe₃O₄αAu na presença do dendrímero poli(amidoamina) geração 4.0 (Pamam G4). As propriedades físico-químicas do nanomaterial core-shell são estudadas através de análises espectroscópicas, microscopias e eletroquímicas, além de medidas de magnetização. Essas técnicas revelam a formação das Nps Au nas cavidades do Pamam G4 e as interações eletrostáticas entre os grupos funcionais do Pamam G4 e os grupos OH ⁻ e H ⁺ da superfície das Nps magnéticas, as quais dão uma forte estabilidade na configuração da Np Fe₃O₄αAu. Evidencia-se propriedades óticas da Np Au e propriedades superparamagnéticas da Np Fe ₃ O ₄, as quais podem ser usadas para aplicações em nanomedicina. As propriedades electrocatalíticas das Nps são utilizadas na detecção de dopamina (DA). Foram fabricados sensores eletroquímicos das Nps Fe₃O₄αAu, Nps Fe₃O₄ e Nps Au, e caracterizados por técnicas de voltametria cíclica e voltametria de pulso diferencial. A fabricação dos sensores consistiu na deposição de camadas alternadas entre as nanopartículas com o poliânion poly(ácido vinil sulfônico) (PVS) no eletrodo de ITO, levando à configuração de três arquiteturas; ITO - (Fe₃O₄αAu ⁄ PV S), ITO - (Fe₃O₄ ⁄ PV S) e ITO - (Au ⁄ PV S). Um problema encontrado na detecção de DA é que esta tem potenciais de oxidação aproximadamente iguais ao ácido ascórbico (AA) e ao ácido úrico (AU). Portanto, os sensores utilizados na detecção de DA, devem ser altamente seletivos a DA em relação a seus interferentes. Os sensores desenvolvidos aqui mostraram uma boa seletividade e velocidade de resposta na detecção de DA, sendo o sensor ITO - (Fe₃O₄αAu ⁄ PV S) o mais eficiente. As Nps Fe₃O₄αAu revelam maior citotoxicidade nas células cancerígenas comparadas com as células saudáveis, já que as células cancerígenas são mais sensíveis ao estresse oxidativo produzido pelas nanopartículas no interior da célula. / Along with the development of nanomaterials came the knowledge and design of their unique eletronic, optical and catalitycal properties which may be used for a variety of nanotecnological applications. A special class of nanomaterials with interesting characteristics is represented by the CoreαShell nanoparticles, which combine the physicochemical properties of two differerent nanomaterials (including oxides, metals, semiconductors or polymers). This combination provides greater efficiency in applications such as nanoelectronics, sensing, biosensing and biomedical areas. This study reports the synthesis of Fe₃O₄ Np, which in the presence of the polyamido amine generation 4.0 (Pamam G4), is covered with Au Np forming the Fe₃O₄αAu Nps. The nanomaterials had been characterized using spectroscopic, microscopic and electrochemical techniques. The results revealed the formation of Au Nps in the cavities of PAMAM G4 and showed that the electrostatic interactions between the PAMAM functional groups and the OH ⁻ and H ⁺ groups on the surface of the magnetic nanoparticles lead to a strong stability in the configuration of Fe₃O₄αAu Nps. The optical properties of the Au Np (namely the Plasmon resonance band at 542 nm) as well as the superparamagnetic properties of the Fe₃O₄ Np were present in the core-shell nanostrutures. Due to their electrocatalytical properties, the core-shell nanoparticles were employed as active elements for dopamine (DA) detection. The fabrication of the modified electrodes for DA detection consisted in the deposition by LbL technique of alternating layers of nanoparticles and poly(vinyl sulfonic acid) (PVS) on the ITO eletrode, in three distinct architectures: ITO - (Fe₃O₄αAu Fe₃O₄ PV S), ITO - (Fe₃O₄ ⁄ PV S) and ITO - (Au ⁄ PV S). We found a good selectivity and rapid response toward the detection of DA, being the sensor ITO - (Fe₃O₄αAu ⁄ PV S) the most efficient. The effect of Fe₃O₄αAu Nps showed a higher cytotoxicity in cancer cells compared to healthy cells, because cancer cells are more sensitive to oxidative stress produced by the nanoparticles.
19

Síntese e caracterização de nanopartículas Fe3O4@Au e desenvolvimento de sensores para aplicações em nanomedicina / Synthesis and characterization of Fe3O4@Au nanoparticles and development of sensors for application in nanomedicine

Camilo Arturo Suarez Ballesteros 31 July 2012 (has links)
Com o desenvolvimento de novos nanomateriais têm-se descoberto propriedades eletrônicas, elétricas, ópticas e catalíticas únicas para aplicações nanotecnológicas. Entre estes nanomateriais com caraterísticas singulares, estão as nanopartículas (Np) CoreαShell, as quais combinam propriedades físico-químicas de dois materiais diferentes, provendo maior eficiência em aplicações como nanoeletrônica, sensoreamento, biossensoreamento e biomédicas. Neste trabalho, Np CoreαShell são sintetizada com núcleo (Core) de Np Fe₃O₄ e com casca (Shell) de Np Au, formando as Nps Fe₃O₄αAu na presença do dendrímero poli(amidoamina) geração 4.0 (Pamam G4). As propriedades físico-químicas do nanomaterial core-shell são estudadas através de análises espectroscópicas, microscopias e eletroquímicas, além de medidas de magnetização. Essas técnicas revelam a formação das Nps Au nas cavidades do Pamam G4 e as interações eletrostáticas entre os grupos funcionais do Pamam G4 e os grupos OH ⁻ e H ⁺ da superfície das Nps magnéticas, as quais dão uma forte estabilidade na configuração da Np Fe₃O₄αAu. Evidencia-se propriedades óticas da Np Au e propriedades superparamagnéticas da Np Fe ₃ O ₄, as quais podem ser usadas para aplicações em nanomedicina. As propriedades electrocatalíticas das Nps são utilizadas na detecção de dopamina (DA). Foram fabricados sensores eletroquímicos das Nps Fe₃O₄αAu, Nps Fe₃O₄ e Nps Au, e caracterizados por técnicas de voltametria cíclica e voltametria de pulso diferencial. A fabricação dos sensores consistiu na deposição de camadas alternadas entre as nanopartículas com o poliânion poly(ácido vinil sulfônico) (PVS) no eletrodo de ITO, levando à configuração de três arquiteturas; ITO - (Fe₃O₄αAu ⁄ PV S), ITO - (Fe₃O₄ ⁄ PV S) e ITO - (Au ⁄ PV S). Um problema encontrado na detecção de DA é que esta tem potenciais de oxidação aproximadamente iguais ao ácido ascórbico (AA) e ao ácido úrico (AU). Portanto, os sensores utilizados na detecção de DA, devem ser altamente seletivos a DA em relação a seus interferentes. Os sensores desenvolvidos aqui mostraram uma boa seletividade e velocidade de resposta na detecção de DA, sendo o sensor ITO - (Fe₃O₄αAu ⁄ PV S) o mais eficiente. As Nps Fe₃O₄αAu revelam maior citotoxicidade nas células cancerígenas comparadas com as células saudáveis, já que as células cancerígenas são mais sensíveis ao estresse oxidativo produzido pelas nanopartículas no interior da célula. / Along with the development of nanomaterials came the knowledge and design of their unique eletronic, optical and catalitycal properties which may be used for a variety of nanotecnological applications. A special class of nanomaterials with interesting characteristics is represented by the CoreαShell nanoparticles, which combine the physicochemical properties of two differerent nanomaterials (including oxides, metals, semiconductors or polymers). This combination provides greater efficiency in applications such as nanoelectronics, sensing, biosensing and biomedical areas. This study reports the synthesis of Fe₃O₄ Np, which in the presence of the polyamido amine generation 4.0 (Pamam G4), is covered with Au Np forming the Fe₃O₄αAu Nps. The nanomaterials had been characterized using spectroscopic, microscopic and electrochemical techniques. The results revealed the formation of Au Nps in the cavities of PAMAM G4 and showed that the electrostatic interactions between the PAMAM functional groups and the OH ⁻ and H ⁺ groups on the surface of the magnetic nanoparticles lead to a strong stability in the configuration of Fe₃O₄αAu Nps. The optical properties of the Au Np (namely the Plasmon resonance band at 542 nm) as well as the superparamagnetic properties of the Fe₃O₄ Np were present in the core-shell nanostrutures. Due to their electrocatalytical properties, the core-shell nanoparticles were employed as active elements for dopamine (DA) detection. The fabrication of the modified electrodes for DA detection consisted in the deposition by LbL technique of alternating layers of nanoparticles and poly(vinyl sulfonic acid) (PVS) on the ITO eletrode, in three distinct architectures: ITO - (Fe₃O₄αAu Fe₃O₄ PV S), ITO - (Fe₃O₄ ⁄ PV S) and ITO - (Au ⁄ PV S). We found a good selectivity and rapid response toward the detection of DA, being the sensor ITO - (Fe₃O₄αAu ⁄ PV S) the most efficient. The effect of Fe₃O₄αAu Nps showed a higher cytotoxicity in cancer cells compared to healthy cells, because cancer cells are more sensitive to oxidative stress produced by the nanoparticles.
20

Capacité de modèles in vitro de complexité différente à prédire les réponses toxiques pulmonaires observées in vivo après exposition aiguë à des nanoparticules de TiO2 et de CeO2 / Predicting the in vivo pulmonary toxicity induced by acute exposure to TiO2 and CeO2 nanoparticules by using in vitro methods

Loret, Thomas 20 March 2017 (has links)
Les nanoparticules (NPs) représentent un danger potentiel pour la santé des travailleurs et du grand public, notamment en cas d’exposition par voie respiratoire. Si une NP est évaluée in vivo comme toxique chez l’animal, cela peut inciter à prendre des mesures pour réduire l’exposition de l’Homme à celle-ci, avant qu’il y ait des conséquences sanitaires graves. Les études in vivo sont donc d’une importance capitale afin de diminuer les potentiels risques sanitaires des NPs pour l’Homme. Néanmoins, dans un contexte de réduction du nombre d’animaux utilisés et compte tenu du nombre important de NPs existantes et de leur grande diversité physico-chimique, la toxicologie a besoin de modèles alternatifs, comme le in vitro, permettant de prédire de manière fiable les potentiels effets pulmonaires chez l’Homme. Des progrès importants ont été faits pour développer des modèles in vitro pulmonaires plus physiologiques et des méthodes d’exposition permettant de simuler l’inhalation de NPs in vitro. Cependant, des incertitudes existent quant à la capacité de ces nouveaux modèles in vitro à prédire les réponses observées in vivo dans les poumons après exposition à des NPs. Dans ce contexte, l’objectif de ce travail a été d’évaluer la capacité de plusieurs méthodes in vitro, de complexité différente, à prédire les effets toxiques observés in vivo chez le rat après exposition aiguë (24h) pulmonaire à des NPs métalliques faiblement solubles de TiO2 et de CeO2. Dans un premier temps, des expérimentations in vitro ont été effectuées afin d’évaluer si exposer des cellules alvéolaires à l’interface air-liquide (ALI) à des aérosols de NPs de TiO2 et de CeO2, générait des résultats différents par rapport à des expositions classiques à des suspensions en submergé. Dans un second temps, des expérimentations in vivo par aspiration intratrachéale ont été réalisées afin de comparer les réponses toxiques pulmonaires in vitro avec celles obtenues in vivo. Pour comparer les réponses pulmonaires in vivo et in vitro, des référentiels de dose similaires, notamment la masse par unité de surface ou par macrophage, ont été utilisés. Après 24h d’exposition, des réponses biologiques significatives (inflammation principalement) ont été observées in vitro à des doses inférieures à l’ALI par rapport au submergé. Nous avons par ailleurs souligné la nécessité de prendre en compte les doses réellement déposées sur les cellules ainsi que le débit de dose pour effectuer les comparaisons entre les deux méthodes d’exposition in vitro utilisées. Nous avons ensuite comparé les résultats in vitro avec ceux obtenus in vivo. Nous avons constaté que la méthode ALI générait des résultats plus prédictifs du in vivo, en termes de niveau d’activation des réponses toxiques à 24h. Finalement, nous avons établi un classement des quatre NPs utilisées dans notre étude et celles-ci ont été classées similairement in vivo et in vitro et quelle que soit la méthode utilisée in vitro. Nous avons par ailleurs montré l’importance de considérer la surface active des NPs pour établir ce classement. En conclusion, notre approche nous a permis de mieux évaluer le fossé existant entre le in vivo et le in vitro. Nos résultats soulignent l’intérêt d’utiliser des méthodes in vitro plus réalistes et plus proches de la physiologie humaine dans le but de modéliser les potentiels effets indésirables des NPs pour l’Homme. Cela ouvre des perspectives quant à l’utilisation et au développement de méthodologies in vitro de plus en plus représentatives des conditions d’exposition in vivo. / Nanoparticles (NPs) represent a potential danger for workers and public, especially after inhalation. When a NP is shown toxic for the lungs in vivo in animals, this can incite regulators to implement measures to reduce human exposure risks. The in vivo studies are thus of utmost importance in reducing the potential health risks for humans. However, in a context of a diminution in the number of animals used in experimentations and considering the high number of NPs used and their physicochemical diversity, there is an urgent need for alternative methods, like the in vitro, which could be used to predict the potential health effects of NPs in human. Many progresses have been made recently to develop more physiological cell models and exposure methods simulating the inhalation of NPs in vitro. Nevertheless, uncertainties remain regarding the capacity of these new in vitro methods to predict the biological responses observed in vivo into the lungs after exposure to NPs. In this context, the aim of our study was to assess the ability of several in vitro methods, differing in complexity, to predict the adverse responses observed in vivo in rat lungs after acute exposure (24h) to several metallic and poorly soluble TiO2 and CeO2 NPs. For this, in vitro experimentations were first performed to assess if exposing alveolar cells in monoculture or in co-culture at the ALI interface to aerosols of NPs, generated different results compared to classic exposure in submerged conditions to suspensions. In a second step, rats were exposed by intratracheal aspiration of NP suspensions to compare the biological responses in vitro to those obtained in vivo. To compare the pulmonary responses in vivo and in vitro, similar dose metrics were selected, including the mass per surface unit or per macrophage. After 24h of exposure, significant biological responses (mostly inflammation) were observed at lower doses at the ALI compared to in submerged conditions. Moreover, we highlighted the necessity to take into account the deposited dose on the cells and the timing of the dose delivery in order to compare the two exposure methods used in vitro. When we compared the responses in vitro to those observed in vivo, we noticed that the ALI methods generated more predictive results than the submerged one, in term of biological activation levels after 24h of exposure. Finally, a ranking of the four NPs used in our study was provided and the NPs were ranked similarly both in vivo and in vitro and whatever the exposure method used in vitro. We also showed the importance of the surface area when ranking the poorly soluble NPs. In conclusion, the gap existing between the in vivo and the in vitro has been evaluated in our study. Our results highlighted the relevance of using more realistic in vitro exposure methods to model the potential adverse effects of NPs for human. This brings perspectives about using and developing in vitro methods mimicking more closely the in vivo exposure conditions.

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