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2.
Neuropsychopharmacology ; 49(11): 1767-1774, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38918578

RESUMO

A coherent sense of self is crucial for social functioning and mental health. The N-methyl-D-aspartate antagonist ketamine induces short-term dissociative experiences and has therefore been used to model an altered state of self-perception. This randomized double-blind placebo-controlled cross-over study investigated the mechanisms for ketamine's effects on the bodily sense of self in the context of affective touch. Thirty healthy participants (15 females/15 males, age 19-39) received intravenous ketamine or placebo while performing self-touch and receiving touch by someone else during functional MRI - a previously established neural measure of tactile self-other-differentiation. Afterwards, tactile detection thresholds during self- and other-touch were assessed, as well as dissociative states, interoceptive awareness, and social touch attitudes. Compared to placebo, ketamine administration elicited dissociation and reduced neural activity associated with self-other-differentiation in the right temporoparietal cortex, which was most pronounced during other-touch. This reduction correlated with ketamine-induced reductions in interoceptive awareness. The temporoparietal cortex showed higher connectivity to somatosensory cortex and insula during other- compared to self-touch. This difference was augmented by ketamine, and correlated with dissociation strength for somatosensory cortex. These results demonstrate that disrupting the self-experience through ketamine administration affects neural activity associated with self-other-differentiation in a region involved in touch perception and social cognition, especially with regard to social touch by someone else. This process may be driven by ketamine-induced effects on top-down signaling, rendering the processing of predictable self-generated and unpredictable other-generated touch more similar. These findings provide further evidence for the intricate relationship of the bodily self with the tactile sense.


Assuntos
Estudos Cross-Over , Ketamina , Imageamento por Ressonância Magnética , Autoimagem , Percepção do Tato , Humanos , Ketamina/farmacologia , Ketamina/administração & dosagem , Feminino , Masculino , Método Duplo-Cego , Adulto , Adulto Jovem , Percepção do Tato/efeitos dos fármacos , Percepção do Tato/fisiologia , Antagonistas de Aminoácidos Excitatórios/farmacologia , Antagonistas de Aminoácidos Excitatórios/administração & dosagem , Tato/efeitos dos fármacos , Interocepção/efeitos dos fármacos , Interocepção/fisiologia , Afeto/efeitos dos fármacos , Afeto/fisiologia
4.
Sci Rep ; 13(1): 20846, 2023 11 27.
Artigo em Inglês | MEDLINE | ID: mdl-38012238

RESUMO

The increasing use of additive manufacturing (AM) techniques (e.g., 3D-printing) offers many advantages but at the same time presents some challenges. One concern is the possible exposure and health risk related to metal containing particles of different sizes. Using the nickel-based alloys Hastelloy X (HX) and Inconel 939 (IN939) as a case, the aim of this cross-disciplinary study was to increase the understanding on possible health hazards and exposure. This was done by performing in-depth characterization of virgin, reused and condensate powders, testing in vitro toxicity (cytotoxicity, genotoxicity, oxidative stress), and measuring occupational airborne exposure. The results showed limited metal release from both HX and IN939, and slightly different surface composition of reused compared to virgin powders. No or small effects on the cultured lung cells were observed when tested up to 100 µg/mL. Particle background levels in the printing facilities were generally low, but high transient peaks were observed in relation to sieving. Furthermore, during post processing with grinding, high levels of nanoparticles (> 100,000 particles/cm3) were noted. Urine metal levels in AM operators did not exceed biomonitoring action limits. Future studies should focus on understanding the toxicity of the nanoparticles formed during printing and post-processing.


Assuntos
Ligas , Exposição Ocupacional , Ligas/toxicidade , Níquel/toxicidade , Exposição Ocupacional/efeitos adversos , Exposição Ocupacional/análise , Metais , Comércio , Tamanho da Partícula
5.
Environ Res ; 231(Pt 2): 116186, 2023 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-37224945

RESUMO

Exposure to particulate matter (PM) has been associated with a wide range of adverse health effects, but it is still unclear how particles from various transport modes differ in terms of toxicity and associations with different human health outcomes. This literature review aims to summarize toxicological and epidemiological studies of the effect of ultrafine particles (UFPs), also called nanoparticles (NPs, <100 nm), from different transport modes with a focus on vehicle exhaust (particularly comparing diesel and biodiesel) and non-exhaust as well as particles from shipping (harbor), aviation (airport) and rail (mainly subway/underground). The review includes both particles collected in laboratory tests and the field (intense traffic environments or collected close to harbor, airport, and in subway). In addition, epidemiological studies on UFPs are reviewed with special attention to studies aimed at distinguishing the effects of different transport modes. Results from toxicological studies indicate that both fossil and biodiesel NPs show toxic effects. Several in vivo studies show that inhalation of NPs collected in traffic environments not only impacts the lung, but also triggers cardiovascular effects as well as negative impacts on the brain, although few studies compared NPs from different sources. Few studies were found on aviation (airport) NPs, but the available results suggest similar toxic effects as traffic-related particles. There is still little data related to the toxic effects linked to several sources (shipping, road and tire wear, subway NPs), but in vitro results highlighted the role of metals in the toxicity of subway and brake wear particles. Finally, the epidemiological studies emphasized the current limited knowledge of the health impacts of source-specific UFPs related to different transport modes. This review discusses the necessity of future research for a better understanding of the relative potencies of NPs from different transport modes and their use in health risk assessment.


Assuntos
Poluentes Atmosféricos , Material Particulado , Humanos , Material Particulado/toxicidade , Material Particulado/análise , Poluentes Atmosféricos/análise , Biocombustíveis , Emissões de Veículos/toxicidade , Emissões de Veículos/análise , Pulmão/química
6.
Forensic Sci Int ; 348: 111691, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37116244

RESUMO

In the past 15 years, close to 1000 of new psychoactive substances (NPS) have been reported in Europe and globally. At the time of identification, data on safety, toxicity and carcinogenic potential of many NPS are not available or very limited. To work more efficiently, a strategy and collaboration between the Public Health Agency of Sweden (PHAS) and the National Board of Forensic Medicine was established involving in vitro receptor activity assays to demonstrate neurological activity of NPS. This report summarizes the first results on the synthetic cannabinoid receptor agonists (SCRAs), and subsequent actions taken by PHAS. A total of 18 potential SCRAs were selected by PHAS for in vitro pharmacological characterization. 17 compounds could be acquired and investigated for their activity on the human cannabinoid-1 (CB1) receptors expressed together with the AequoScreen system in CHO-K1 cells. Dose-response curves were established using eight different concentrations in triplicates at three occasions with JWH-018 as reference. For the MDMB-4en-PINACA, MMB-022, ACHMINACA, ADB-BUTINACA, 5F-CUMYL-PeGACLONE, 5C-AKB48, NM-2201, 5F-CUMYL-PINACA, JWH-022, 5Cl-AB-PINACA, MPhP-2201, 5F-AKB57 the half maximal effective concentration values ranged from 2.2 nM (5F-CUMYL-PINACA) to 171 nM (MMB-022). EG-018 and 3,5-AB-CHMFUPPYCA were none-active. The results contributed to 14 of these compounds being scheduled as narcotics in Sweden. In conclusion, many of the emerging SCRAs are potent activators of the CB1 receptor in vitro, although some lack activity or are partial agonists. The new strategy proved useful when data on psychoactive effects of the SCRAs under investigation were not available or limited.


Assuntos
Canabinoides , Saúde Pública , Humanos , Suécia , Canabinoides/farmacologia , Agonistas de Receptores de Canabinoides/farmacologia , Fármacos do Sistema Nervoso Central , Medição de Risco , Receptor CB1 de Canabinoide
7.
Nanomaterials (Basel) ; 12(17)2022 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-36080081

RESUMO

Among the various nanomaterials present in society, many contain metals or metal compounds [...].

8.
Front Toxicol ; 4: 845987, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35295219

RESUMO

Genotoxicity is an important endpoint to assess for understanding the risks associated with nanoparticles (NPs). Most genotoxicity studies performed on NPs have focused on primary genotoxicity analyzed by comet- or micronuclei (MN) assay using microscopic scoring. Here, we established a protocol for a more efficient version of MN assessment using flow cytometry and, importantly, both primary and secondary (inflammation-driven) genotoxicity was assessed. Human bronchial epithelial cells (HBEC-3kt) were exposed to nickel oxide (NiO) NPs directly or indirectly. The indirect exposure was done to assess secondary genotoxicity, and in this case immune cells (THP-1 derived macrophages) were exposed on inserts and the HBEC were cultured in the lower compartment. The results in monocultures showed that no increased MN formation was observed in the HBEC cells but instead a clear MN induction was noted in THP-1 cells indicating higher sensitivity. No MN formation was either observed when the HBEC were indirectly exposed, but an increase in DNA strand breaks was detected using the comet assay. Taken together, the present study emphasizes the feasibility of assessing primary and secondary genotoxicity and, furthermore, shows a clear MN induction in THP-1 monoculture following NiO NPs exposure.

9.
Arch Toxicol ; 96(4): 969-985, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35188583

RESUMO

Translating particle dose from in vitro systems to relevant human exposure remains a major challenge for the use of in vitro studies in assessing occupational hazard and risk of particle exposure. This study aimed to model the lung deposition and retention of welding fume particles following occupational scenarios and subsequently compare the lung doses to those used in vitro. We reviewed published welding fume concentrations and size distributions to identify input values simulating real-life exposure scenarios in the multiple path particle dosimetry (MPPD) model. The majority of the particles were reported to be below 0.1 µm and mass concentrations ranged between 0.05 and 45 mg/m3. Following 6-h exposure to 5 mg/m3 with a count median diameter of 50 nm, the tracheobronchial lung dose (0.89 µg/cm2) was found to exceed the in vitro cytotoxic cell dose (0.125 µg/cm2) previously assessed by us in human bronchial epithelial cells (HBEC-3kt). However, the tracheobronchial retention decreased rapidly when no exposure occurred, in contrast to the alveolar retention which builds-up over time and exceeded the in vitro cytotoxic cell dose after 1.5 working week. After 1 year, the tracheobronchial and alveolar retention was estimated to be 1.15 and 2.85 µg/cm2, respectively. Exposure to low-end aerosol concentrations resulted in alveolar retention comparable to cytotoxic in vitro dose in HBEC-3kt after 15-20 years of welding. This study demonstrates the potential of combining real-life exposure data with particle deposition modelling to improve the understanding of in vitro concentrations in the context of human occupational exposure.


Assuntos
Poluentes Ocupacionais do Ar , Exposição Ocupacional , Soldagem , Poluentes Ocupacionais do Ar/análise , Poluentes Ocupacionais do Ar/toxicidade , Humanos , Exposição por Inalação/estatística & dados numéricos , Pulmão , Exposição Ocupacional/análise , Exposição Ocupacional/estatística & dados numéricos , Tamanho da Partícula
10.
Toxicology ; 467: 153100, 2022 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-35032623

RESUMO

Additive manufacturing (AM) or "3D-printing" is a ground-breaking technology that enables the production of complex 3D parts. Its rapid growth calls for immediate toxicological investigations of possible human exposures in order to estimate occupational health risks. Several laser-based powder bed fusion AM techniques are available of which many use metal powder in the micrometer range as feedstock. Large energy input from the laser on metal powders generates several by-products, like spatter and condensate particles. Due to often altered physicochemical properties and composition, spatter and condensate particles can result in different toxicological responses compared to the original powder particles. The toxicity of such particles has, however, not yet been investigated. The aim of the present study was to investigate the toxicity of condensate/spatter particles formed and collected upon selective laser melting (SLM) printing of metal alloy powders, including a nickel-chromium-based superalloy (IN939), a nickel-based alloy (Hastelloy X, HX), a high-strength maraging steel (18Ni300), a stainless steel (316L), and a titanium alloy (Ti6Al4V). Toxicological endpoints investigated included cytotoxicity, generation of reactive oxygen species (ROS), genotoxicity (comet and micronucleus formation), and inflammatory response (cytokine/chemokine profiling) following exposure of human bronchial epithelial cells (HBEC) or monocytes/macrophages (THP-1). The results showed no or minor cytotoxicity in the doses tested (10-100 µg/mL). Furthermore, no ROS generation or formation of micronucleus was observed in the HBEC cells. However, an increase in DNA strand breaks (detected by comet assay) was noted in cells exposed to HX, IN939, and Ti6Al4V, whereas no evident release of pro-inflammatory cytokine was observed from macrophages. Particle and surface characterization showed agglomeration in solution and different surface oxide compositions compared to the nominal bulk content. The extent of released nickel was small and related to the nickel content of the surface oxides, which was largely different from the bulk content. This may explain the limited toxicity found despite the high Ni bulk content of several powders. Taken together, this study suggests relatively low acute toxicity of condensates/spatter particles formed during SLM-printing using IN939, HX, 18Ni300, 316L, and Ti6Al4V as original metal powders.


Assuntos
Ligas/toxicidade , Células Epiteliais/efeitos dos fármacos , Pulmão/efeitos dos fármacos , Macrófagos/efeitos dos fármacos , Pneumonia/induzido quimicamente , Impressão Tridimensional , Ligas de Cromo/toxicidade , Citocinas/genética , Citocinas/metabolismo , Dano ao DNA , Relação Dose-Resposta a Droga , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Humanos , Mediadores da Inflamação/metabolismo , Pulmão/metabolismo , Pulmão/patologia , Macrófagos/metabolismo , Macrófagos/patologia , Testes de Mutagenicidade , Estresse Oxidativo/efeitos dos fármacos , Pneumonia/genética , Pneumonia/metabolismo , Pneumonia/patologia , Pós , Espécies Reativas de Oxigênio/metabolismo , Medição de Risco , Aço Inoxidável/toxicidade , Células THP-1 , Titânio/toxicidade
11.
Neuropsychopharmacology ; 47(4): 824-831, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34750564

RESUMO

Social drinking is common, but it is unclear how moderate levels of alcohol influence decision making. Most prior studies have focused on adverse long-term effects on cognitive and executive function in people with alcohol use disorders (AUD). Some studies have investigated the acute effects of alcohol on decision making in healthy people, but have predominantly used small samples and focused on a narrow selection of tasks related to personal decision making, e.g., delay or probability discounting. Here, we conducted a large (n = 264), preregistered randomized placebo-controlled study (RCT) using a parallel group design, to systematically assess the acute effects of alcohol on measures of decision making in both personal and social domains. We found a robust effect of a 0.6 g/kg dose of alcohol on both moral judgment and altruistic behavior, but no effects on several measures of risk taking or waiting impulsivity. These findings suggest that alcohol at low to moderate doses selectively moderates decision making in the social domain, and promotes utilitarian decisions over those dictated by rule-based ethical principles (deontological). This is consistent with existing theory that emphasizes the dual roles of shortsighted information processing and salient social cues in shaping decisions made under the influence of alcohol. A better understanding of these effects is important to understand altered social functioning during alcohol intoxication.


Assuntos
Alcoolismo , Alcoolismo/psicologia , Tomada de Decisões , Etanol/efeitos adversos , Humanos , Julgamento , Princípios Morais
12.
Int J Nanomedicine ; 16: 5895-5908, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34475755

RESUMO

INTRODUCTION: Gold nanoparticles (AuNPs) have the potential to be used in various biomedical applications, partly due to the inertness and stability of gold. Upon intravenous injection, the NPs interact with the mononuclear phagocyte system, first with monocytes in the blood and then with macrophages in tissue. The NP-macrophage interaction will likely affect the stability of the AuNPs, but this is seldom analyzed. This study aimed to elucidate the role of macrophages in the biodissolution of AuNPs and underlying mechanisms. METHODS: With an in vitro dissolution assay, we used inductively coupled plasma mass spectrometry to quantitatively compare the dissolution of 5 and 20 nm AuNPs coated with citrate or PEG in cell medium alone or in the presence of THP1-derived macrophages at 24 hours. In addition, we analyzed the cell dose, compared extra- and intracellular dissolution, and explored the possible role of reactive nitrogen species. RESULTS: The results showed a higher cellular dose of the citrate-coated AuNPs, but dissolution was mainly evident for those sized 5 nm, irrespective of coating. The macrophages clearly assisted the dissolution, which was approximately fivefold higher in the presence of macrophages. The dissolution, however, appeared to take place mainly extracellularly. Acellular experiments demonstrated that peroxynitrite can initiate oxidation of gold, but a ligand is required to keep the gold ions in solution. CONCLUSION: This study suggests extracellular dissolution of AuNPs in the presence of macrophages, likely with the contribution of the release of reactive nitrogen species, and provides new insight into the fate of AuNPs in the body.


Assuntos
Ouro , Nanopartículas Metálicas , Humanos , Macrófagos , Sistema Fagocitário Mononuclear , Espécies Reativas de Nitrogênio
13.
ACS Catal ; 11(15): 9128-9135, 2021 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-34476111

RESUMO

Performing fundamental operando catalysis studies under realistic conditions is a key to further develop and increase the efficiency of industrial catalysts. Operando X-ray photoelectron spectroscopy (XPS) experiments have been limited to pressures, and the relevance for industrial applications has been questioned. Herein, we report on the CO oxidation experiment on Pd(100) performed at a total pressure of 1 bar using XPS. We investigate the light-off regime and the surface chemical composition at the atomistic level in the highly active phase. Furthermore, the observed gas-phase photoemission peaks of CO2, CO, and O2 indicate that the kinetics of the reaction during the light-off regime can be followed operando, and by studying the reaction rate of the reaction, the activation energy is calculated. The reaction was preceded by an in situ oxidation study in 7% O2 in He and a total pressure of 70 mbar to confirm the surface sensitivity and assignment of the oxygen-induced photoemission peaks. However, oxygen-induced photoemission peaks were not observed during the reaction studies, but instead, a metallic Pd phase is present in the highly active regime under the conditions applied. The novel XPS setup utilizes hard X-rays to enable high-pressure studies, combined with a grazing incident angle to increase the surface sensitivity of the measurement. Our findings demonstrate the possibilities of achieving chemical information of the catalyst, operando, on an atomistic level, under industrially relevant conditions.

14.
Arch Toxicol ; 95(9): 2961-2975, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34287684

RESUMO

Welders are daily exposed to various levels of welding fumes containing several metals. This exposure can lead to an increased risk for different health effects which serves as a driving force to develop new methods that generate less toxic fumes. The aim of this study was to explore the role of released metals for welding particle-induced toxicity and to test the hypothesis that a reduction of Cr(VI) in welding fumes results in less toxicity by comparing the welding fume particles of optimized Cr(VI)-reduced flux-cored wires (FCWs) to standard FCWs. The welding particles were thoroughly characterized, and toxicity (cell viability, DNA damage and inflammation) was assessed following exposure to welding particles as well as their released metal fraction using cultured human bronchial epithelial cells (HBEC-3kt, 5-100 µg/mL) and human monocyte-derived macrophages (THP-1, 10-50 µg/mL). The results showed that all Cr was released as Cr(VI) for welding particles generated using standard FCWs whereas only minor levels (< 3% of total Cr) were released from the newly developed FCWs. Furthermore, the new FCWs were considerably less cytotoxic and did not cause any DNA damage in the doses tested. For the standard FCWs, the Cr(VI) released in cell media seemed to explain a large part of the cytotoxicity and DNA damage. In contrast, all particles caused rather similar inflammatory effects suggesting different underlying mechanisms. Taken together, this study suggests a potential benefit of substituting standard FCWs with Cr(VI)-reduced wires to achieve less toxic welding fumes and thus reduced risks for welders.


Assuntos
Poluentes Ocupacionais do Ar/toxicidade , Cromo/toxicidade , Aço Inoxidável/toxicidade , Soldagem , Poluentes Ocupacionais do Ar/análise , Brônquios/citologia , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Cromo/análise , Cromo/química , Dano ao DNA/efeitos dos fármacos , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/patologia , Humanos , Inflamação/induzido quimicamente , Inflamação/patologia , Macrófagos/efeitos dos fármacos , Exposição Ocupacional/efeitos adversos , Exposição Ocupacional/análise , Aço Inoxidável/análise , Células THP-1
15.
J Immunotoxicol ; 18(1): 74-84, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34019775

RESUMO

Sensitization to a contact allergen brings with it a lifelong risk to develop allergic contact dermatitis. Inflammation is an important part of the skin sensitizing mechanism, and understanding how different haptens stimulate the immune system, as well as the role played by different cell types present in skin, may be helpful for developing optimized in vitro models for risk assessment of new chemicals or mixtures. The aim of this study was to compare the cytokine profile following exposure of cells representing keratinocytes (HaCaT), monocytes (THP-1) and a co-culture of these cells to three clinically important skin sensitizers: cobalt (II) chloride (CoCl2), methylisothiazolinone (MI) and p-phenylenediamine (PPD). Secretion of ten pro-inflammatory cytokines was measured using multiplexing. The results showed that the cytokine response differed substantially between the three cell assays. CoCl2 caused an increase of IL-8 in HaCaT cells, while the induction of also IL-13 and IL-1ß was observed in THP-1 cells and co-cultures. MI induced six cytokines in HaCaT cells but only IL-1ß in the THP-1 cells and four cytokines in the co-culture. Interestingly, the IL-1ß response was massive in the co-culture. PPD caused release of IL-1ß in all three models as well as IL-8 in the co-culture. Control experiments with two non-sensitizers and irritants (lactic acid and sodium dodecyl sulfate) showed no effect on IL-8 or IL-1ß in the co-culture. Taken together, results from this exploratory analysis show unique cytokine profiles dependent on the type of hapten and cell model. Importantly, all three haptens triggered secretion of IL-1ß and IL-8 in a co-culture of HaCaT cells and THP-1 cells, representing the most robust test system.


Assuntos
Citocinas , Monócitos , Técnicas de Cocultura , Queratinócitos , Pele
16.
Chem Res Toxicol ; 34(6): 1481-1495, 2021 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-33856197

RESUMO

The fluorescent probe 2',7'-dichlorofluorescein diacetate (DCFH-DA) together with the enzyme horseradish peroxidase (HRP) is widely used in nanotoxicology to study acellular reactive oxygen species (ROS) production from nanoparticles (NPs). This study examined whether HRP adsorbs onto NPs of Mn, Ni, and Cu and if this surface process influences the extent of metal release and hence the ROS production measurements using the DCFH assay in phosphate buffered saline (PBS), saline, or Dulbecco's modified Eagle's medium (DMEM). Adsorption of HRP was evident onto all NPs and conditions, except for Mn NPs in PBS. The presence of HRP resulted in an increased release of copper from the Cu NPs in PBS and reduced levels of nickel from the Ni NPs in saline. Both metal ions in solution and the adsorption of HRP onto the NPs can change the activity of HRP and thus influence the ROS results. The effect of HRP on the NP reactivity was shown to be solution chemistry dependent. Most notable was the evident affinity/adsorption of phosphate toward the metal NPs, followed by a reduced adsorption of HRP, the concomitant reduction in released manganese from the Mn NPs, and increased levels of released metals from the Cu NPs in PBS. Minor effects were observed for the Ni NPs. The solution pH should be monitored since the release of metals can change the solution pH and the activity of HRP is known to be pH-dependent. It is furthermore essential that solution pH adjustments are made following the addition of NaOH during diacetyl removal of DCFH-DA. Even though not observed for the given exposure conditions of this study, released metal ions could possibly induce agglomeration or partial denaturation of HRP, which in turn could result in steric hindrance for H2O2 to reach the active site of HRP. This study further emphasizes the influence of HRP on the background kinetics, its solution dependence, and effects on measured ROS signals. Different ways of correcting for the background are highlighted, as this can result in different interpretations of generated results. The results show that adsorption of HRP onto the metal NPs influenced the extent of metal release and may, depending on the investigated system, result in either under- or overestimated ROS signals if used together with the DCFH assay. HRP should hence be used with caution when measuring ROS in the presence of reactive metallic NPs.


Assuntos
Fluoresceínas/química , Peroxidase do Rábano Silvestre/química , Nanopartículas Metálicas/química , Metais Pesados/química , Espécies Reativas de Oxigênio/análise , Adsorção , Peroxidase do Rábano Silvestre/metabolismo , Tamanho da Partícula , Espécies Reativas de Oxigênio/metabolismo , Propriedades de Superfície
17.
Front Toxicol ; 3: 653386, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35295099

RESUMO

Lung cancer, one of the most common and deadly forms of cancer, is in some cases associated with exposure to certain types of particles. With the rise of nanotechnology, there is concern that some engineered nanoparticles may be among such particles. In the absence of epidemiological evidence, assessment of nanoparticle carcinogenicity is currently performed on a time-consuming case-by-case basis, relying mainly on animal experiments. Non-animal alternatives exist, including a few validated cell-based methods accepted for regulatory risk assessment of nanoparticles. Furthermore, new approach methodologies (NAMs), focused on carcinogenic mechanisms and capable of handling the increasing numbers of nanoparticles, have been developed. However, such alternative methods are mainly applied as weight-of-evidence linked to generally required animal data, since challenges remain regarding interpretation of the results. These challenges may be more easily overcome by the novel Adverse Outcome Pathway (AOP) framework, which provides a basis for validation and uptake of alternative mechanism-focused methods in risk assessment. Here, we propose an AOP for lung cancer induced by nanosized foreign matter, anchored to a selection of 18 standardized methods and NAMs for in silico- and in vitro-based integrated assessment of lung carcinogenicity. The potential for further refinement of the AOP and its components is discussed in relation to available nanosafety knowledge and data. Overall, this perspective provides a basis for development of AOP-aligned alternative methods-based integrated testing strategies for assessment of nanoparticle-induced lung cancer.

18.
Nanomaterials (Basel) ; 10(9)2020 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-32961914

RESUMO

Silver nanoparticles (AgNPs) are commonly used in commercial and medical applications. However, AgNPs may induce toxicity, extracellular matrix (ECM) changes and inflammatory responses. Fibroblasts are key players in remodeling processes and major producers of the ECM. The aims of this study were to explore the effect of AgNPs on cell viability, both ex vivo in murine precision cut lung slices (PCLS) and in vitro in human lung fibroblasts (HFL-1), and immunomodulatory responses in fibroblasts. PCLS and HFL-1 were exposed to AgNPs with different sizes, 10 nm and 75 nm, at concentrations 2 µg/mL and 10 µg/mL. Changes in synthesis of ECM proteins, growth factors and cytokines were analyzed in HFL-1. Ag10 and Ag75 affected cell viability, with significantly reduced metabolic activities at 10 µg/mL in both PCLS and HFL-1 after 48 h. AgNPs significantly increased procollagen I synthesis and release of IL-8, prostaglandin E2, RANTES and eotaxin, whereas reduced IL-6 release was observed in HFL-1 after 72 h. Our data indicate toxic effects of AgNP exposure on cell viability ex vivo and in vitro with altered procollagen and proinflammatory cytokine secretion in fibroblasts over time. Hence, careful characterizations of AgNPs are of importance, and future studies should include timepoints beyond 24 h.

19.
PLoS One ; 15(7): e0235202, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32614875

RESUMO

BACKGROUND: Cervical cancer is a highly preventable disease. To not attend an organized cervical cancer screening program increases the risk for cervical dysplasia and cervical cancer. The aim was to investigate the participation rate in three different intervention groups for non- attendees in the Swedish national program for cervical screening. The participation in the recommended follow up, and the histology found were also examined. METHOD: Population-based randomized control trial. It included10,614 women that had not participated in the cervical cancer screening programme during the last six years (ages 30-49) and the last eight years (ages 50-64) were randomised 1:1:1(telephone call from a midwife (offering the choice between a visit for a pap smear or an HPV self-sampling test); an HPV self-sampling test only; or the routine procedure with a yearly invitation). RESULTS: In the intention to treat analysis the participation rates were 25.5% (N = 803/3146) vs 34.1% (N = 1047/3068) and 7.0% (N = 250/3538) (p<0.001) for telephone, HPV self-test and control groups respectively. In the by protocol analysis including women that answered the phone call the participation rates were 31.7% (N = 565/1784) vs 26.1% (N = 788/3002) and 7.0% (N = 250/3538) (p<0.001) for telephone, HPV self-test and control groups. The corresponding results in the by protocol analysis including women that did not answer the phone call was 19.7% (N = 565/2870) vs 26.1% (N = 788/3002) and 7.0% (N = 250/3538) (p< 0.001). The majority of the women 63,4% (1131/1784) who answered the telephone wanted to participate either by booking a visit for pap smear (38,5%) or to be sent a HPV self- sampling test (24,9%) (p<0.001). Women who chose an HPV self-test were older and gave anxiety/ fear as a reason to decline participation, and they were also less likely to participate in the follow-up if found to be HPV-positive compared to the women who chose a Pap smear. The attendance to the recommended follow-up after abnormality was in total 87%. The non-attendees had a three or eight times higher risk of having a cytology result of HSIL or suspected SCC respectively, in the index sample compared to women screened as recommended (OR 3.3 CI 95% 1.9-5.2, OR 8.6 CI 1.6-30). A total of ten SCC and one adenocarcinoma were found in the histopathology results from the non-attendee group with a study intervention, while there was only one SCC in the non-attendee group without any study intervention (p = 0.02, OR 8.1 CI 95% 1.2-350). CONCLUSIONS: Our study suggests, according to intention to treat analysis, that the best intervention to get as many non-attendees as possible to participate is to send an HPV self-sampling test together with an invitation letter. Almost 90% of women in the study with an abnormal index sample attended follow-up. This is high enough to indicate that interventions to increase the participation among non-attendees are meaningful. REGISTRY: International Standard Randomised Controlled Trial Number (ISRCTN) Registration number ISRCTN78719765.


Assuntos
Infecções por Papillomavirus/diagnóstico , Neoplasias do Colo do Útero/diagnóstico , Adulto , Alphapapillomavirus/isolamento & purificação , Detecção Precoce de Câncer/métodos , Feminino , Seguimentos , Humanos , Análise de Intenção de Tratamento , Programas de Rastreamento/métodos , Pessoa de Meia-Idade , Teste de Papanicolaou , Manejo de Espécimes/métodos , Suécia , Esfregaço Vaginal
20.
Nanomaterials (Basel) ; 10(4)2020 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-32230801

RESUMO

Relevant in vitro assays that can simulate exposure to nanoparticles (NPs) via inhalation are urgently needed. Presently, the most common method employed is to expose lung cells under submerged conditions, but the cellular responses to NPs under such conditions might differ from those observed at the more physiological air-liquid interface (ALI). The aim of this study was to investigate the cytotoxic and inflammatory potential of CeO2 NPs (NM-212) in a co-culture of A549 lung epithelial cells and differentiated THP-1 cells in both ALI and submerged conditions. Cellular dose was examined quantitatively using inductively coupled plasma mass spectrometry (ICP-MS). The role of serum and LPS-priming for IL-1ß release was further tested in THP-1 cells in submerged exposure. An aerosol of CeO2 NPs was generated by using the PreciseInhale® system, and NPs were deposited on the co-culture using XposeALI®. No or minor cytotoxicity and no increased release of inflammatory cytokines (IL-1ß, IL-6, TNFα, MCP-1) were observed after exposure of the co-culture in ALI (max 5 µg/cm2) or submerged (max 22 µg/cm2) conditions. In contrast, CeO2 NPs cause clear IL-1ß release in monocultures of macrophage-like THP-1, independent of the presence of serum and LPS-priming. This study demonstrates a useful approach for comparing effects at various in-vitro conditions.

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