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2.
Hepatology ; 68(1): 200-214, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29377208

RESUMO

A dysbalance between effector T cells (Tconv) and regulatory T cells (Tregs) and impaired Treg function can cause autoimmune liver disease. Therefore, it is important to identify molecular mechanisms that control Treg homeostasis. Carcinoembryonic antigen-related cell adhesion molecule 1 (CEACAM1; CD66a) is an immune coreceptor with dichotomous roles in T-cell regulation: its short isoform (CEACAM1S) can activate T cells and induce Tregs, whereas its long isoform (CEACAM1L), containing two intracellular immune receptor tyrosine-based inhibitory motifs, can inhibit activated T-cell function. In the liver, CEACAM1 has antifibrotic effects in models of nonalcoholic steatohepatitis. However, its role in immune-mediated hepatitis is unknown. In the mouse model of concanavalin A-induced CD4+ T-cell-dependent liver injury, liver damage was aggravated and persisted in Ceacam1-/- mice. Concomitantly, we observed hyperexpansion of Tconv, but reduction of interleukin (IL)-2 production and hepatic forkhead box protein P3+ (Foxp3+ )CD4+ Treg numbers. CEACAM1-/- CD4+ T cells showed impaired IL-2-mediated signal transducer and activator of transcription 5 (STAT5) phosphorylation, which correlated with a failure of naïve CEACAM1-/- CD4+ T cells to convert into Tregs in vitro. Furthermore, CEACAM1-/- Tregs expressed reduced levels of Foxp3, CD25, and B-cell lymphoma 2. Adoptive transfer experiments demonstrated that hepatic Treg expansion and suppressive activity required CEACAM1 expression on both CD4+ T cells and Tregs. We identified predominant CEACAM1S expression on hepatic CD4+ T cells and Tregs from mice with acute liver injury and expression of both isoforms in liver-derived CD4+ T-cell clones from patients with liver injury. CONCLUSION: Our data suggest that CEACAM1S expression in CD4+ T cells augments IL-2 production and STAT5 phosphorylation leading to enhanced Treg induction and stability, which, ultimately, confers protection from T-cell-mediated liver injury. (Hepatology 2018;68:200-214).


Assuntos
Antígenos CD/fisiologia , Moléculas de Adesão Celular/fisiologia , Hepatite Autoimune/imunologia , Linfócitos T Reguladores/fisiologia , Animais , Estudos de Casos e Controles , Concanavalina A , Feminino , Humanos , Interleucina-2/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Cultura Primária de Células , Fator de Transcrição STAT5/metabolismo
4.
Eur J Cancer ; 172: 130-137, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35763872

RESUMO

INTRODUCTION: Cigarette smoking represents the main risk factor for cancer development; however, less is known about the effects of active smoking on the outcome of cancer patients receiving systemic treatment, radiation therapy, or surgery. METHODS: A systematic review and meta-analysis were conducted searching the PubMed® and Web of Science® Library databases using specific Medical Subject Headings terms. Studies reporting on the prognostic impact of the smoking status concerning survival endpoints in cancer patients treated with systemic treatment, radiation therapy, or surgery were eligible for inclusion. RESULTS: Of 1.380 articles reviewed, 12 reports including data from 31.785 patients with six different cancer types were considered eligible for inclusion. According to the meta-analysis of the overall effect, active smoking during cancer treatment was associated with an impaired overall survival (OS) and cancer-specific mortality (CSM) as compared to former or never smokers (OS: hazard ratio (HR) = 1.61, 95% CI: 1.19-2.17, p = 0.007; CSM: HR = 1.25, 95% CI: 1.01-1.54, p = 0.046). Moreover, smoking cessation led to a similar OS and CSM when comparing former to never smoking patients (OS: HR = 1.01, 95% CI: 0.87-1.18, p = 0.818; CSM: HR = 1.04, 95% CI: 0.91-1.20, p = 0.324). CONCLUSION: These results underline active smoking during cancer treatment as an independent adverse prognostic factor, while smoking cessation can result in similar outcomes compared to never smokers. Limitations of the study were a substantial study heterogeneity concerning different cancer entities and variations of treatment modalities.


Assuntos
Neoplasias , Abandono do Hábito de Fumar , Humanos , Neoplasias/radioterapia , Prognóstico , Fatores de Risco , Fumar/efeitos adversos
5.
Environ Toxicol Chem ; 40(8): 2229-2239, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33844353

RESUMO

There are currently few suitable test systems for the chronic toxicity testing of aquatic macroinvertebrates under stream conditions. Therefore, a new test system mimicking running water conditions was developed for testing with lotic insects. This system uses small test cages, with 10 of these suspended inside each 25-L container and rotating at 0.1 m/s, to create a water flow for the individual organism inside each cage. To test the performance of the new exposure system, chronic effects (21 d) of the neonicotinoid imidacloprid were investigated with field-collected larvae of the stonefly Protonemura sp. Endpoints were survival, growth, and/or emergence (depending on the developmental stage of the larvae at the start of the exposure). Two experiments conducted 1 yr apart showed good reproducibility: growth 10% effect concentration (EC10) values were 15.3 and 18.5 µg/L and no-observed-effect concentration (NOEC) values were 30.3 and 21.5 µg/L. A third experiment, performed with further-developed larval instars, showed a significant effect of imidacloprid on emergence (with EC10 of 5.97 µg/L and NOEC of 2.89 µg/L) and a significant effect on survival (with median lethal concentration of 44.7 µg/L). The results of the present study show that the newly developed test system provides a suitable approach for toxicity testing with stonefly larvae and potentially for other lotic macroinvertebrate species. Environ Toxicol Chem 2021;40:2229-2239. © 2021 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC.


Assuntos
Inseticidas , Poluentes Químicos da Água , Animais , Insetos , Inseticidas/análise , Larva , Neonicotinoides/toxicidade , Nitrocompostos/toxicidade , Reprodutibilidade dos Testes , Água , Poluentes Químicos da Água/análise
6.
Integr Environ Assess Manag ; 13(2): 267-279, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28127947

RESUMO

A SETAC Pellston Workshop® "Environmental Hazard and Risk Assessment Approaches for Endocrine-Active Substances (EHRA)" was held in February 2016 in Pensacola, Florida, USA. The primary objective of the workshop was to provide advice, based on current scientific understanding, to regulators and policy makers; the aim being to make considered, informed decisions on whether to select an ecotoxicological hazard- or a risk-based approach for regulating a given endocrine-disrupting substance (EDS) under review. The workshop additionally considered recent developments in the identification of EDS. Case studies were undertaken on 6 endocrine-active substances (EAS-not necessarily proven EDS, but substances known to interact directly with the endocrine system) that are representative of a range of perturbations of the endocrine system and considered to be data rich in relevant information at multiple biological levels of organization for 1 or more ecologically relevant taxa. The substances selected were 17α-ethinylestradiol, perchlorate, propiconazole, 17ß-trenbolone, tributyltin, and vinclozolin. The 6 case studies were not comprehensive safety evaluations but provided foundations for clarifying key issues and procedures that should be considered when assessing the ecotoxicological hazards and risks of EAS and EDS. The workshop also highlighted areas of scientific uncertainty, and made specific recommendations for research and methods-development to resolve some of the identified issues. The present paper provides broad guidance for scientists in regulatory authorities, industry, and academia on issues likely to arise during the ecotoxicological hazard and risk assessment of EAS and EDS. The primary conclusion of this paper, and of the SETAC Pellston Workshop on which it is based, is that if data on environmental exposure, effects on sensitive species and life-stages, delayed effects, and effects at low concentrations are robust, initiating environmental risk assessment of EDS is scientifically sound and sufficiently reliable and protective of the environment. In the absence of such data, assessment on the basis of hazard is scientifically justified until such time as relevant new information is available. Integr Environ Assess Manag 2017;13:267-279. © 2017 The Authors. Integrated Environmental Assessment and Management published by Wiley Periodicals, Inc. on behalf of Society of Environmental Toxicology & Chemistry (SETAC).


Assuntos
Disruptores Endócrinos/análise , Exposição Ambiental/estatística & dados numéricos , Poluentes Ambientais/análise , Conferências de Consenso como Assunto , Ecotoxicologia , Disruptores Endócrinos/normas , Disruptores Endócrinos/toxicidade , Poluentes Ambientais/normas , Poluentes Ambientais/toxicidade , Medição de Risco
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