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1.
Toxicology ; : 153964, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-39362579

RESUMO

Electronic cigarettes, commonly referred to as e-cigarettes have gained popularity over recent years especially among young individuals. In the light of the escalating prevalence of the use of these products and their potential for long-term health effects, in this study as the first of its kind a comprehensive toxicological profiling of the liquid from a panel of unregulated e-cigarettes seized in the UK was undertaken using an in vitro co-culture model of the upper airways. The data showed that e-cigarettes caused a dose dependent increase in cell death and inflammation manifested by enhanced release of IL1ß and IL6. Furthermore, the e-cigarettes induced oxidative stress as demonstrated by a reduction of intracellular glutathione and an increase in generation of reactive oxygen species. Moreover, the assessment of genotoxicity showed significant DNA strand breaks (following exposure to Tigerblood flavoured e-cigarette). Moreover, relevant to the toxicological observations, was the detection of varying and frequently high levels of hazardous metals including cadmium, copper, nickel and lead. This study highlights the importance of active and ongoing collaborations between academia, governmental organisations and policy makers (Trading standards, Public Health) and national health service in tackling vape addiction and better informing the general public regarding the risks associated with e-cigarette usage.

2.
Methods Protoc ; 7(5)2024 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-39311375

RESUMO

This protocol describes a robust method for the extraction of intra and extracellular metabolites of gut bacterial mono and co-cultures. In recent years, the co-culture techniques employed in the field of microbiology have demonstrated significant importance in regard to understanding cell-cell interactions, cross-feeding, and the metabolic interactions between different bacteria, fungi, and microbial consortia which enable the mimicking of complex co-habitant conditions. This protocol highlights a robust reproducible physiologically relevant culture and extraction protocol for the co-culture of gut bacterium. The novel extraction steps are conducted without using quenching and cell disruption through bead-cell methods, freeze-thaw cycles, and sonication, which tend to affect the physical and biochemical properties of intracellular metabolites and secretome. The extraction procedure of inoculated bacterial co-cultures and monocultures use fast vacuum filtration and centrifugation. The extraction methodology is fast, effective, and robust, requiring 4 h to complete.

3.
Chemosphere ; 364: 143032, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39111678

RESUMO

Nano and microplastics are defined as particles smaller than 100 nm and 5 mm respectively. The widespread production and use of plastics in everyday life has resulted in significant accumulation of plastic debris in the environment. Over the last two decades there are increased concerns regarding the potential entry and accumulation of plastics in the human body with ingestion being one of the most important routes of exposure. However, the magnitude and nature of potential toxic effects of plastic exposure to human health is not yet fully understood. The liver is the body's principal detoxification organ and critically to this study recognized as the main accumulation site for particulates. In this study as the first of its kind the health impacts of long term low repeated polystyrene microplastics (1 and 5 µm) exposure was investigated in a functionally active 3D liver microtissue model, composed of primary human hepatocytes, Kupffer cells, sinusoidal endothelial cells and hepatic stellate cells. The highlight from the data includes microplastic-induced dose (3.125-25 µg/ml) and time dependent (up to 504 h) increase in cell death and inflammation manifested by enhanced release of IL6, IL8 and TNF-α. The exposure to repeated dosing of the plastics also resulted in notable pathology manifested as aberrant tissue architecture, such as dilated bile canaliculi and large lipid droplets inside the hepatic cells. This toxicity matched extremely well to the accumulation of the materials with the cells of microtissue predominately in the organ macrophages. This study highlights the real issue and danger of microplastic exposure with potential for long-term accumulation and adverse effects of non-biodegradable plastics within the liver.


Assuntos
Hepatócitos , Células de Kupffer , Fígado , Microplásticos , Humanos , Microplásticos/toxicidade , Fígado/efeitos dos fármacos , Hepatócitos/efeitos dos fármacos , Células de Kupffer/efeitos dos fármacos , Células Estreladas do Fígado/efeitos dos fármacos , Células Endoteliais/efeitos dos fármacos , Poliestirenos/toxicidade , Células Cultivadas , Fator de Necrose Tumoral alfa/metabolismo , Interleucina-6/metabolismo , Interleucina-8/metabolismo
4.
NanoImpact ; 35: 100523, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39059749

RESUMO

This manuscript discusses the challenges of applying New Approach Methodologies (NAMs) for safe by design and regulatory risk assessment of advanced nanomaterials (AdNMs). The authors propose a framework for Next Generation Risk Assessment of AdNMs involving NAMs that is aligned to the conventional risk assessment paradigm. This framework is exposure-driven, endpoint-specific, makes best use of pre-existing information, and can be implemented in tiers of increasing specificity and complexity of the adopted NAMs. The tiered structure of the approach, which effectively combines the use of existing data with targeted testing will allow safety to be assessed cost-effectively and as far as possible with even more limited use of vertebrates. The regulatory readiness of state-of-the-art emerging NAMs is assessed in terms of Transparency, Reliability, Accessibility, Applicability, Relevance and Completeness, and their appropriateness for AdNMs is discussed in relation to each step of the risk assessment paradigm along with providing perspectives for future developments in the respective scientific and regulatory areas.


Assuntos
Nanoestruturas , Medição de Risco/métodos , Nanoestruturas/toxicidade , Nanoestruturas/efeitos adversos , Humanos , Animais , Nanotecnologia/métodos
5.
J Toxicol Environ Health B Crit Rev ; 26(8): 442-467, 2023 11 17.
Artigo em Inglês | MEDLINE | ID: mdl-37786264

RESUMO

Drug-Induced Liver Injury (DILI) constitutes hepatic damage attributed to drug exposure. DILI may be categorized as hepatocellular, cholestatic or mixed and might also involve immune responses. When DILI occurs in dose-dependent manner, it is referred to as intrinsic, while if the injury occurs spontaneously, it is termed as idiosyncratic. This review predominately focused on idiosyncratic liver injury. The established molecular mechanisms for DILI include (1) mitochondria dysfunction, (2) increased reactive oxygen species levels, (3) presence of elevated apoptosis and necrosis, (4) and bile duct injuries associated with immune mediated pathways. However, it should be emphasized that the underlying mechanisms responsible for DILI are still unknown. Prevention strategies are critical as incidences occur frequently, and treatment options are limited once the injury has developed. The aim of this review was to utilize retrospective cohort studies from across the globe to gain insight into epidemiological patterns. This review considers (1) what is currently known regarding the mechanisms underlying DILI, (2) discusses potential risk factors and (3) implications of the coronavirus pandemic on DILI presentation and research. Future perspectives are also considered and discussed and include potential new biomarkers, causality assessment and reporting methods.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas , Hepatopatias , Humanos , Estudos Retrospectivos , Doença Hepática Induzida por Substâncias e Drogas/epidemiologia , Doença Hepática Induzida por Substâncias e Drogas/etiologia , Hepatopatias/epidemiologia , Fatores de Risco
6.
Bioengineering (Basel) ; 10(10)2023 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-37892864

RESUMO

The fusion of machine learning and biomedical research offers novel ways to understand, diagnose, and treat various health conditions. However, the complexities of biomedical data, coupled with the intricate process of developing and deploying machine learning solutions, often pose significant challenges to researchers in these fields. Our pivotal achievement in this research is the introduction of the Automatic Semantic Machine Learning Microservice (AIMS) framework. AIMS addresses these challenges by automating various stages of the machine learning pipeline, with a particular emphasis on the ontology of machine learning services tailored to the biomedical domain. This ontology encompasses everything from task representation, service modeling, and knowledge acquisition to knowledge reasoning and the establishment of a self-supervised learning policy. Our framework has been crafted to prioritize model interpretability, integrate domain knowledge effortlessly, and handle biomedical data with efficiency. Additionally, AIMS boasts a distinctive feature: it leverages self-supervised knowledge learning through reinforcement learning techniques, paired with an ontology-based policy recording schema. This enables it to autonomously generate, fine-tune, and continually adapt to machine learning models, especially when faced with new tasks and data. Our work has two standout contributions demonstrating that machine learning processes in the biomedical domain can be automated, while integrating a rich domain knowledge base and providing a way for machines to have self-learning ability, ensuring they handle new tasks effectively. To showcase AIMS in action, we have highlighted its prowess in three case studies of biomedical tasks. These examples emphasize how our framework can simplify research routines, uplift the caliber of scientific exploration, and set the stage for notable advances.

7.
J Toxicol Environ Health B Crit Rev ; 26(1): 1-27, 2023 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-36474307

RESUMO

The integration of nanomaterials (NMs) into an ever-expanding number of daily used products has proven to be highly desirable in numerous industries and applications. Unfortunately, the same "nano" specific physicochemical properties, which make these materials attractive, may also contribute to hazards for individuals exposed to these materials. In 2021, it was estimated that 7 out of 10 deaths globally were accredited to chronic diseases, such as chronic liver disease, asthma, and cardiovascular-related illnesses. Crucially, it is also understood that a significant proportion of global populace numbering in the billions are currently living with a range of chronic undiagnosed health conditions. Due to the significant number of individuals affected, it is important that people suffering from chronic disease also be considered and incorporated in NM hazard assessment strategies. This review examined and analyzed the literature that focused on NM-induced adverse health effects in models which are representative of individuals exhibiting pre-existing medical conditions with focus on the pulmonary, cardiovascular, hepatic, gastrointestinal, and central nervous systems. The overall objective of this review was to outline available data, highlighting the important role of pre-existing disease in NM-induced toxicity with the aim of establishing a weight of evidence approach to inform the public on the potential hazards posed by NMs in both healthy and compromised persons in general population.


Assuntos
Nanoestruturas , Cobertura de Condição Pré-Existente , Humanos , Nanoestruturas/toxicidade , Pulmão , Fígado
8.
Toxicol In Vitro ; 85: 105473, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36108805

RESUMO

To reduce, replace, and refine in vivo testing, there is increasing emphasis on the development of more physiologically relevant in vitro test systems to improve the reliability of non-animal-based methods for hazard assessment. When developing new approach methodologies, it is important to standardize the protocols and demonstrate the methods can be reproduced by multiple laboratories. The aim of this study was to assess the transferability and reproducibility of two advanced in vitro liver models, the Primary Human multicellular microtissue liver model (PHH) and the 3D HepG2 Spheroid Model, for nanomaterial (NM) and chemical hazard assessment purposes. The PHH model inter-laboratory trial showed strong consistency across the testing sites. All laboratories evaluated cytokine release and cytotoxicity following exposure to titanium dioxide (TiO2) and zinc oxide (ZnO) nanoparticles. No significant difference was observed in cytotoxicity or IL-8 release for the test materials. The data were reproducible with all three laboratories with control readouts within a similar range. The PHH model ZnO induced the greatest cytotoxicity response at 50.0 µg/mL and a dose-dependent increase in IL-8 release. For the 3D HepG2 spheroid model, all test sites were able to construct the model and demonstrated good concordance in IL-8 cytokine release and genotoxicity data. This trial demonstrates the successful transfer of new approach methodologies across multiple laboratories, with good reproducibility for several hazard endpoints.


Assuntos
Óxido de Zinco , Humanos , Óxido de Zinco/toxicidade , Reprodutibilidade dos Testes , Interleucina-8 , Fígado , Linhagem Celular , Esferoides Celulares
9.
Adv Exp Med Biol ; 1357: 259-273, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35583648

RESUMO

Manufactured nanomaterials (NMs) offer incredible scientific and societal benefits but their potential hazard to human health is not yet fully comprehended. In the last decade, a significant body of evidence indicates that certain NMs are capable of translocating from the primary exposure site (skin, lungs and gastrointestinal tract) to a number of secondary organs which includes the liver. Moreover, recent advances in the field of nanomedicine has resulted in increasing direct intravenous injection of NMs with the liver being a particularly important organ with regards to potential toxic effects and accumulation of said materials. It is generally acknowledged that it is not always possible to make direct or meaningful comparisons between in vitro and in vivo xenobiotic-induced toxicological responses. One of the main reasons for the lack of comparability between the testing strategies is that biological responses are not often alike which can in part be attributed to the numerous limitations of traditional mono-cellular in vitro test systems which are acting as a surrogate for a whole organ. In an attempt to address and highlight this important issue, this chapter will discuss the progress made in the production and validation oof next generation more physiologically relevant multi-cellular in vitro models of skin, GIT and the liver utilised for the assessment of the NM-induced toxicological effects.


Assuntos
Nanoestruturas , Humanos , Técnicas In Vitro , Fígado , Nanoestruturas/toxicidade
10.
Part Fibre Toxicol ; 19(1): 32, 2022 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-35525968

RESUMO

The incorporation of nanomaterials (NMs) in consumer products has proven to be highly valuable in many sectors. Unfortunately, however, the same nano specific physicochemical properties, which make these material attractive, might also contribute to hazards for people exposed to these materials. The physicochemical properties of NMs will impact their interaction with biological surroundings and influence their fate and their potential adverse effects such as genotoxicity. Due to the large and expanding number of NMs produced, their availability in different nanoforms (NFs) and their utilization in various formats, it is impossible for risk assessment to be conducted on an individual NF basis. Alternative methods, such as grouping are needed for streamlining hazard assessment. The GRACIOUS Framework provides a logical and science evidenced approach to group similar NFs, allowing read-across of hazard information from source NFs (or non-NFs) with adequate hazard data to target NFs that lack such data. Here, we propose a simple three-tiered testing strategy to gather evidence to determine whether different NFs are sufficiently similar with respect to their potential to induce genotoxicity, in order to be grouped. The tiered testing strategy includes simple in vitro models as well as a number of alternative more complex multi-cellular in vitro models to allow for a better understanding of secondary NM-induced DNA damage, something that has been more appropriate in vivo until recently.


Assuntos
Nanoestruturas , Dano ao DNA , Humanos , Nanoestruturas/química , Nanoestruturas/toxicidade , Medição de Risco/métodos
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