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1.
Toxicol In Vitro ; : 105824, 2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38614139

RESUMO

The TRPV1 receptor, which is known to contribute significantly to pain perception, has recently been identified as a useful tool for predicting eye stinging potential in cosmetics. In this study, HEK-293 cells with high TRPV1 expression were utilized to evaluate calcium influx related to receptor activation triggered by chemicals and cosmetic formulations. The cells were exposed to increasing concentrations of substances to cause or not some aggression to the eye, and TRPV1 activity was assessed by measuring intracellular FURA-2 AM fluorescence signal. To confirm TRPV1 channel activation, capsazepine, a capsaicin antagonist, was employed in addition to using capsaicin as a positive control. The study's results indicate that this novel model can identify compounds known to cause some aggression to the eye, such as stinging, considering a cut-off value of 60% of Ca2+ influx exposed to the lowest evaluated concentration (0.00032%). When applied to the cosmetic baby formulation, although the presented model exhibited higher sensitivity by classifying as stinging formulations that had previously undergone clinical testing and were deemed non-stinging, the assay could serve as a valuable in vitro tool for predicting human eye stinging sensation and can be used as a tier 1 in an integrated testing strategy.

2.
Toxicology ; 503: 153750, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38360295

RESUMO

Occupational asthma covers a group of work-related diseases whose clinical manifestations include airway hyperresponsiveness and airflow limitation. Although the chemical respiratory allergy (CRA) induced by Low Molecular Weight (LMW) sensitizers is a major concern, especially in terms of the regulatory framework, to date there are no methods available for preclinically addressing this toxicological outcome, as its mechanistic background is not fully understood at molecular or cellular levels. This paper proposes a mechanistic study applying New Approach Methodologies (NAM) of the pro-inflammatory and functional effects triggered by LMW respiratory allergens in different respiratory tract cell lines, including bronchial epithelial (BEAS-2B), lung fibroblast (MRC-5), and endothelial cells (EA.hy926), and an analysis of the capacity of such chemicals to interact with the mucin protein, to address certain toxicodynamic aspects of such compounds. The results showed that some of the sensitizers evaluated interact with mucin, the main protein mucus component, but the toxicant-mucin complex formation does not seem to be a common feature of different chemical classes of allergens. At a cellular level, sensitizers promoted an increase in IL-8, IL-6, and IL-1ß production in the evaluated cell types. It also impaired the MUC1 expression by bronchial cells and activated endothelial cells, thereby increasing the ICAM-I surface expression. Taken together, our results showed that these aforementioned cell types participate in the CRA Adverse Outcome Pathway and must be considered when developing preclinical testing strategies, particularly investigating danger signal production after exposure to LMW sensitizers in different tissue compartments.


Assuntos
Células Endoteliais , Pulmão , Humanos , Brônquios/metabolismo , Biomarcadores/metabolismo , Alérgenos/toxicidade , Mucinas
3.
Toxicology ; 503: 153756, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38369009

RESUMO

Chemical Respiratory Allergy (CRA) is triggered after exposure to Low Molecular Weight (LMW) sensitizers and manifests clinically as asthma and rhinitis. From a risk/toxicity assessment point of view, there are few methods, none of them validated, for evaluating the respiratory sensitization potential of chemicals once the in vivo-based models usually employed for inhalation toxicity addressment do not comprise allergenicity endpoints specifically. Based on that, we developed, characterized, and evaluated the applicability of a 3D-tetraculture airway model reconstructed with bronchial epithelial, fibroblasts, endothelial and monocytic cell lines. Moreover, we exposed the tissue to maleic anhydride (MA) aerosols to challenge the model and subsequently assessed inflammatory and functional aspects of the tissue. The reconstructed tissue presented phenotypic biomarkers compatible with human bronchial epithelium, and MA aerosol exposure triggered an increased IL-8 and IL-6 production, reactive oxygen species (ROS) formation, and apoptosis of epithelial cells. Besides, augmented IL-8 production by monocytic cells was also found, correlating with dendritic cell activation within the co-culture model after MA exposure. Our results demonstrated that the 3D-tetraculture bronchial model presents hallmarks related to human airways' structure and function. Additionally, exposure to a respiratory sensitizer induced inflammatory and functional alterations in the reconstructed tissue, rendering it a valuable tool for exploring the mechanistic framework of chemically induced respiratory sensitization.


Assuntos
Asma , Interleucina-8 , Humanos , Interleucina-8/metabolismo , Aerossóis e Gotículas Respiratórios , Brônquios , Asma/metabolismo , Células Epiteliais/metabolismo
4.
Toxicol Res (Camb) ; 13(1): tfae005, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38239269

RESUMO

Background: Pesticides are indispensable for the cultivation of crops, especially those of economic importance, such as soybeans. Data on the annual use of herbicides in crops show that they correspond to 50%, making it the most used in agriculture. Aim: Therefore, the aim of this study was to evaluate the toxicity of the three commercial herbicides (clomazone, glyphosate, and sulfentrazone) in THP-1 cells. Methods: Cells were incubated with 0-5,000 mg/L of the herbicides for 24 h at 37 °C for cytotoxicity evaluation. Additionally, a few toxicological pathways such as reactive species generation, mitochondrial impairment, and interleukin profile, which have been previously involved in the toxicity of pesticides, were also evaluated. Results: A potential immunotoxic effect of the herbicides on THP-1 cells was observed, especially glyphosate, as it is a powerful agent of cellular immunotoxicity. It was also possible to verify an increase in oxidative stress and IL-8 levels and mitochondrial dysfunction. Conclusion: All herbicides showed cytotoxic effects in THP-1 monocytes, which were related to mitochondrial impairment.

5.
Altern Lab Anim ; 52(1): 60-68, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38061994

RESUMO

The Brazilian National Network of Alternative Methods (RENAMA), which is linked to the Ministry of Science, Technology and Innovation, is currently comprised of 51 laboratories from CROs, academia, industry and government. RENAMA's aim is to develop and validate new approach methodologies (NAMs), as well as train researchers and disseminate information on their use - thus reducing Brazilian, and consequently Latin American, dependence on external technology. Moreover, it promotes the adoption of NAMs by educators and trained researchers, as well as the implementation of good laboratory practice (GLP) and the use of certified products. The RENAMA network started its activities in 2012, and was originally comprised of three central laboratories - the National Institute of Metrology, Quality and Technology (INMETRO); the National Institute of Quality Control in Health (INCQS); and the National Brazilian Biosciences Laboratory (LNBio) - and ten associated laboratories. In 2022, RENAMA celebrated its 10th anniversary, a milestone commemorated by the organisation of a meeting attended by different stakeholders, including the RENAMA-associated laboratories, academia, non-governmental organisations and industry. Ninety-six participants attended the meeting, held on 26 May 2022 in Balneário Camboriú, SC, Brazil, as part of the programme of the XXIII Brazilian Congress of Toxicology 2022. Significant moments of the RENAMA were remembered, and new goals and discussion themes were established. The lectures highlighted recent innovations in the toxicological sciences that have translated into the assessment of consumer product safety through the use of human-relevant NAMs instead of the use of existing animal-based approaches. The challenges and opportunities in accepting such practices for regulatory purposes were also presented and discussed.


Assuntos
Aniversários e Eventos Especiais , Laboratórios , Animais , Humanos , Brasil
6.
Regul Toxicol Pharmacol ; 145: 105499, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37805107

RESUMO

Certain chemicals and/or their byproducts are photoactivated by UV/VIS and trigger a dermal allergenic response, clinically recognized as photoallergic contact dermatitis (PACD). It is important to identify the chemicals which are potentially photoallergenic, not only for establishing the correct differential diagnosis between PACD and other photodermatoses, but also as causative agents which should be avoided as a preventative measure. Moreover, materials with photoallergenic properties need to be correctly identified to allow thorough safety assessments for their use in finished products (e.g. cosmetics). Development of methods for predicting photoallergenicity potential of chemicals has advanced at slow pace in recent years. To date, there are no validated methods for photosensitisation potential of chemicals for regulatory purposes, although it remains a required endpoint in some regions. The purpose of this review is to explore the mechanisms potentially involved in the photosensitisation process and discuss the methods available in the literature for identification of photosensitisers. The review also explores the possibilities of further research investment required to develop human-relevant new approach methodologies (NAMs) and next generation risk assessment (NGRA) approaches, considering the current perspectives and needs of the Toxicology for the 21st Century.


Assuntos
Cosméticos , Dermatite Fotoalérgica , Humanos , Dermatite Fotoalérgica/diagnóstico , Dermatite Fotoalérgica/etiologia , Alérgenos , Cosméticos/efeitos adversos , Medição de Risco
7.
Support Care Cancer ; 31(9): 517, 2023 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-37566179

RESUMO

PURPOSE: To assess the effect of a mucoadhesive herbal medicine containing curcuminoids and a glycerinated extract of Bidens pilosa L. (FITOPROT) in association with photobiomodulation (PBM) therapy and a Preventive Oral Care Program (POCP) compared to PBM and POCP in the treatment of radiotherapy (RT)-induced oral mucositis (ROM) and in the quality of life of these patients. METHODS: A double-blind clinical trial was performed with head and neck cancer patients undergoing RT or chemoradiotherapy. Participants were randomized into two groups: Group 1 (n=27): PBM and POCP; and Group 2 (n=25): PBM, POCP and FITOPROT. The PBM protocol was daily irradiation, 660 nm, 25mW, 0.25 J/point from the first until the last day of RT. The FITOPROT was used as mouthwash twice a day. ROM was evaluated based on the scales of the World Health Organization and National Cancer Institute. The quality of life was evaluated using the University of Washington Questionnaire, OHIP-14 and Patient-Reported Oral Mucositis Symptom Scale. The MMAS-8 questionnaire was used to evaluated the adherence to POCP and FITOPROT. Data were collected at baseline, 7th, 14th, 21st, and 30th RT sessions. RESULTS: No statistical differences were found between the groups for the ROM evaluation. Both groups experienced worsening of the quality of life during the RT. No statistically significant differences between groups were observed for any of the instruments evaluated. CONCLUSION: The results suggest that PBM associated with FITOPROT and POCP control the severity of ROM and stabilize the QoL of patients with head and neck cancer. TRIAL REGISTRATION: Brazilian Registry of Clinical Trials (ReBEC-RBR-9vddmr; UTN code: U1111-1193-2066), registered in August 8th, 2017.


Assuntos
Bidens , Neoplasias de Cabeça e Pescoço , Terapia com Luz de Baixa Intensidade , Estomatite , Humanos , Qualidade de Vida , Curcuma , Estomatite/tratamento farmacológico , Estomatite/etiologia , Estomatite/prevenção & controle , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Neoplasias de Cabeça e Pescoço/radioterapia , Extratos Vegetais/uso terapêutico , Terapia com Luz de Baixa Intensidade/métodos
8.
Toxicol In Vitro ; 90: 105602, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37146919

RESUMO

Respiratory sensitization encompasses a group of diseases that manifest through airway hyperresponsiveness and airflow limitation. Although the concerns regarding human health, to date there are still no validated methods for preclinical assessment of this class of toxicants once the chemical respiratory allergy mechanistic framework is not fully understood. As Dendritic Cells (DCs) are the bridging elements between innate and adaptative immune responses, we preliminarily investigated the biological alterations triggered by seven different LMW respiratory allergens in the DC model THP-1. The results have shown that exposure to respiratory allergens promoted alterations in DCs maturation/activation status and triggered pro-inflammatory changes in these cells through increased expression for the CD86/HLA-DR/CD11c surface biomarkers and enhancement in IL-8 and IL-6 production by exposed THP-1 cells. Therefore, evidence was found to support the startpoint for chemical respiratory allergy pathogenesis elucidation, subsidizing the contribution of dendritic cells in such pathomechanisms.


Assuntos
Células Dendríticas , Hipersensibilidade , Humanos , Linhagem Celular , Células THP-1 , Alérgenos/toxicidade
9.
ALTEX ; 40(3): 534-540, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36888967

RESUMO

Progress in developing new tools, assays, and approaches to assess human hazard and health risk provides an opportunity to re-evaluate the necessity of dog studies for the safety evaluation of agrochemicals. A workshop was held where partic­ipants discussed the strengths and limitations of past use of dogs for pesticide evaluations and registrations. Opportunities were identified to support alternative approaches to answer human safety questions without performing the required 90-day dog study. Development of a decision tree for determining when the dog study might not be necessary to inform pesticide safety and risk assessment was proposed. Such a process will require global regulatory authority participation to lead to its acceptance. The identification of unique effects in dogs that are not identified in rodents will need further evaluation and determination of their relevance to humans. The establishment of in vitro and in silico approaches that can provide critical data on relative species sensitivity and human relevance will be an important tool to advance the decision process. Promising novel tools including in vitro comparative metabolism studies, in silico models, and high-throughput assays able to identify metabolites and mechanisms of action leading to development of adverse outcome pathways will need further development. To replace or eliminate the 90-day dog study, a collaborative, multidisciplinary, international effort that transcends organi­zations and regulatory agencies will be needed in order to develop guidance on when the study would not be necessary for human safety and risk assessment.


Assuntos
Rotas de Resultados Adversos , Praguicidas , Animais , Cães , Humanos , Agroquímicos/toxicidade , Praguicidas/toxicidade , Medição de Risco , Simulação por Computador
10.
Adv Pharm Bull ; 13(1): 150-159, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36721819

RESUMO

Purpose: The emergence of the COVID-19 pandemic has led to the search for potential therapeutic responses for various aspects of this disease. Fruits of Pterodon emarginatus Vogel (Fabaceae), sucupira, have been used in Brazilian traditional medicine because of their anti-inflammatory properties, which have been proven in vivo, in vitro, and in silico. Therefore, the aim of this work is to evaluate P. emarginatus oleoresin and isolated diterpenes by in vitro anti-inflammatory models. Methods: In this study, the mechanisms underlying the anti-inflammatory activity of P. emarginatus oleoresin and vouacapanes 6α,19ß-diacetoxy-7ß,14ß-dihydroxyvouacapan (V1), 6α-acetoxy-7ß,14ß-dihydroxyvouacapan (V2), and methyl 6α-acetoxy-7ß-hydroxyvouacapan-17ß-oate (V3) were investigated in HaCaT cells. Results: Oleoresin, V2, and V3 inhibited phospholipase A2 (30.78%, 24.96%, and 77.64%, respectively). Both vouacapanes also inhibited the expression of COX-2 (28.3% and 33.17%, respectively). The production of interleukin 6 (IL-6) was inhibited by oleoresin by 35.47%. However, oleoresin did not interfere with Nrf-2 expression or IL-8 production. Conclusion: The results support the ethnomedicinal use of P. emarginatus oleoresin as an anti-inflammatory herbal medicine, and also highlight P. emarginatus oleoresin and isolated vouacapanes as an attractive therapeutic approach for COVID-19 through the reduction or chronological control of the inflammatory mediators IL-6, cyclooxygenase-2 (COX-2), phospholipase A2, and INF-y (indirectly) during the SARS-CoV-2 infection process.

11.
Food Chem Toxicol ; 170: 113457, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36244458

RESUMO

This study developed an air-liquid interface (ALI) corneal model using explants bovine eyes for ocular toxicity assessment of ten chemicals and seven hair straightening mixtures. It was successfully maintained physiologically viable and normal for six days. Both eye damage (GHS cat. 1) and irritating (GHS cat. 2) chemicals induced corneal injury in our model. However, cat. 2 irritants triggered moderate damage when compared to cat. 1 agents, which induced a marked cytotoxicity profile. The mixtures were also able to trigger viability reduction associated with histopathological changes in the corneal tissues, especially when the exposure was via aerosol particles. Thus, the chemical exposure microenvironment simulation seemed to provide more reliable toxicological data. Moreover, mixture-induced corneal damage correlated with increased ROS levels, suggesting a close correlation between tissue death and oxidative stress. Besides mixtures showing the potential to induce moderate/mild ocular toxicity, we could verify that the corneal tissue damage showed reversibility due to the recovery from the injury after exposure to some of the mixtures. Hence, our ex vivo corneal model seems to be a simple and cost-effective approach for future studies related to further investigating the reversibility of damage in the cornea triggered by chemicals and their mixtures.


Assuntos
Alternativas aos Testes com Animais , Neuropatia Óptica Tóxica , Bovinos , Animais , Testes de Toxicidade , Irritantes/toxicidade , Córnea/patologia , Cabelo
12.
Toxicon ; 210: 155-157, 2022 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-35231483

RESUMO

Snake venoms are natural sources of bioactive substances with therapeutic potential. In this work, we evaluated the cytotoxicity of the Crotalus durissus collilineatus, negative crotamine variety and the isolated fraction C0K3N3 in BALB C/3T3 and K562 cell lines. The results indicate that the C0K3N3 protein is more cytotoxic against the K562 tumor cell line than in the 3T3 baseline.


Assuntos
Venenos de Crotalídeos , Crotalus , Animais , Linhagem Celular Tumoral , Venenos de Crotalídeos/metabolismo , Venenos de Crotalídeos/toxicidade , Crotalus/metabolismo , Venenos de Serpentes/toxicidade
13.
Food Chem Toxicol ; 161: 112820, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35033595

RESUMO

Acute inhalation toxicity testing for chemical classification and labeling has been performed using animal models, however, these models have limited predictibility of the toxicity on the respiratory system. Thus, non-animal models have been emerging as alternatives for preclinical assessment of respiratory toxicity of chemicals, comprising in chemico, in vitro, ex vivo, and in silico approaches. In this study, we characterized and evaluated the applicability of a new ex vivo bovine bronchial model for addressing key aspects of pulmonary toxicity. Standardized bronchial fragments were cultured at an air-liquid interface for seven days showing cell viability, morphology, and function during the ex vivo time of cultivation. Different exposure ways, liquid or aerosol exposure, were also studied using paraformaldehyde (PFA) as a positive control. In a concentration-dependent manner, a decrease in tissue viability was observed for aerosols instead of direct liquid exposure upon tissue surface. Moreover, PFA exposure allowed the addressment of several damage biomarkers, including epithelium thickness, mitochondrial activity, ROS production, and caspase-3 activation. Besides, the bronquial tissue was exposed to chemicals from different UN GHS inhalation toxicity categories and presented a concentration-dependent response for most of the evaluated materials. The proposed airway ex vivo model represents a low-cost and reproducible tool applicable for pulmonary toxicity assessment of chemicals.


Assuntos
Fixadores/toxicidade , Formaldeído/toxicidade , Pulmão/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Polímeros/toxicidade , Testes de Toxicidade/métodos , Animais , Biomarcadores/metabolismo , Caspase 3/genética , Caspase 3/metabolismo , Bovinos , Sobrevivência Celular , Regulação da Expressão Gênica/efeitos dos fármacos , Mucina-1/genética , Mucina-1/metabolismo , Espécies Reativas de Oxigênio
14.
Behav Brain Res ; 417: 113582, 2022 01 24.
Artigo em Inglês | MEDLINE | ID: mdl-34536431

RESUMO

The current treatments available for anxiety and depression are only palliative. Full remission has remained elusive, characterizing unmet medical needs. In the scope of an academic drug discovery program, we describe here the design, synthesis, in vitro metabolism prediction and pharmacological characterization of a new piperazine compound, 1-(4-methoxyphenyl)-4-((1-phenyl-1H-pyrazol-4-yl)methyl)piperazine (LQFM005), and of its main putative metabolite, 4-(4-((4-(4-methoxyphenyl)piperazin-1-yl)methyl)- 1H-pyrazol-1-yl)phenol (LQFM235). The production of the metabolite was initially performed by in vitro biotransformation of LQFM005 using Aspergillus candidus and then by chemical synthesis. Oral administration of either 12 or 24 µmol/kg LQFM005 to mice did not affect spontaneous locomotor activity but increased the time spent in the center of the open field. Both LQFM005 and LQFM235 (24 µmol/kg) increased the time spent by the mice in the open arms of the elevated plus maze (EPM), a good indication of anxiolytic-like effect, and decreased the immobility time in the forced swimming test (FST), suggesting an antidepressant-like effect. The previous administration of WAY-100635 (a 5-HT1A antagonist) abolished the effects of LQFM005 in both EPM and FST. Binding experiments showed that LQFM005 and its metabolite bind to the 5-HT1A receptor with a moderate affinity (Ki around 5-9 µM). The two compounds are relatively safe, as indicated by cytotoxic assessment using the 3T3 fibroblast cell line and estimated LD50 around 600 mg/kg. In conclusion, oral administration of the newly synthesized phenylpiperazines produced anxiolytic- and antidepressant-like effects in behavioral tests, putatively in part through the activation of 5-HT1A receptors.


Assuntos
Ansiolíticos/farmacologia , Antidepressivos/farmacologia , Ansiedade/tratamento farmacológico , Depressão/tratamento farmacológico , Piperazinas/farmacologia , Animais , Comportamento Animal/efeitos dos fármacos , Locomoção , Masculino , Camundongos , Piperazinas/antagonistas & inibidores , Piperazinas/metabolismo , Piridinas/antagonistas & inibidores , Natação
15.
Head Neck ; 43(12): 3922-3934, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34655135

RESUMO

BACKGROUND: Oral mucositis (OM) is the significant complication of radio/chemotherapy treatment. This study evaluated the safety and efficacy of a mucoadhesive phytomedication containing curcuminoids and Bidens pilosa L. (FITOPROT) in the prevention/treatment of OM. METHODS: Sixty-two patients were randomized into the group's intervention and placebo. Adverse effect assessment, OM grading, pain, and saliva collection were carried at the 1st, 15th, 21st, and final of radiotherapy (RT). Inflammatory salivary mediators were measured. RESULTS: FITOPROT decreased the severity of OM from the 15th to the final RT, while the placebo showed an increase in the severity (p < 0.05). Intervention group had a lower number of patients with ulcerated OM at the final RT (p < 0.05). Phytomedication prevented increases of IL-8 levels and reduced the salivary nitrite during RT. CONCLUSIONS: FITOPROT does not promote adverse effects, it appears to be effective at reducing the severity of OM, and it controls the concentration of pro-inflammatory mediators.


Assuntos
Bidens , Neoplasias de Cabeça e Pescoço , Estomatite , Quimiorradioterapia , Diarileptanoides/uso terapêutico , Método Duplo-Cego , Humanos , Estomatite/etiologia , Estomatite/prevenção & controle
16.
Braz Oral Res ; 35: e063, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34076188

RESUMO

FITOPROT, which contains curcuminoids and Bidens pilosa L. extract, is an innovative mucoadhesive formulation indicated for the topical treatment of chemoradiotherapy-induced oral mucositis (OM) in patients with advanced and visible oral squamous cell carcinoma. The formulation is used as a mouthwash directly on tumor tissue of patients with advanced neoplasms, without triggering cancer cell proliferation or tumor invasiveness. Thus, the aim of this study was to evaluate the biological effects of FITOPROT on an oral squamous cell carcinoma cell line (SCC-4). The viability of SCC-4 cells was assessed after exposure to FITOPROT using MTT reduction assay. The effects of the mucoadhesive formulation on cell cycle progression and cell death parameters were evaluated using flow cytometry. In addition, the inflammatory profile of the tumor cells was evaluated using the cytometric bead array (CBA) assay. FITOPROT promoted a concentration-dependent decrease in cell viability and cell cycle arrest at the G2/M phase (p < 0.05). Mitochondrial membrane potential was also altered after exposure to the formulation (p < 0.05), in parallel with a reduction in VEGF and IL-8 production (p = 0.01 and p = 0.05, respectively). In summary, the results indicate that FITOPROT reduces SCC-4 cell viability, promotes cell cycle arrest, modulates mitochondrial membrane potential, and exhibits antiangiogenic and anti-inflammatory properties, thus indicating its potential for topical use in patients with OM and visible tumors in the mouth.


Assuntos
Bidens , Carcinoma de Células Escamosas , Neoplasias Bucais , Apoptose , Carcinoma de Células Escamosas/tratamento farmacológico , Linhagem Celular , Proliferação de Células , Diarileptanoides , Humanos , Neoplasias Bucais/tratamento farmacológico
17.
Methods Mol Biol ; 2240: 175-195, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33423234

RESUMO

Historically, the ocular toxicity of manufactured consumer materials has been evaluated using the rabbit in vivo Draize rabbit eye test. The animal data obtained were used by the United Nations Globally Harmonized System of Classification and Labelling of Chemicals (UN GHS) to define the classification and labelling (C&L) for eye damage/irritation endpoint. However, the Draize test, a method which was never formally validated, has been widely criticized because of its technical limitations. In addition, ethical and economic issues and advances in scientific knowledge, and political and public pressures have made animal experimentation unsustainable. This scenario has consequently led to the development of nonanimal testing and protocols/approaches with considerable predictive value and relevance for humans. It is widely accepted that one single nonanimal method cannot cover all the criteria of damage/inflammation assessed by regulatory adopted in vivo animal testing. Thus, integrated testing strategies (ITS) have been proposed, including a tiered testing approach combining different nonanimal testing with different endpoints, which have been used for regulatory purposes, on a case-by-case basis and within integrated approaches to testing and assessment (IATA), to identify materials according to their ability to trigger eye damage. In particular, the top-down and bottom-up approaches have been recommended for the C&L of materials, which cause serious eye damage or eye irritation, respectively. This chapter describes detailed protocols for eye irritation testing based on cells (Short Time Exposure-STE, OECD No. 491/2017), a vascularized membrane (the Hen's Egg Test-Chorioallantoic Membrane-HET-CAM) and corneal tissue (Bovine Corneal Opacity and Permeability-BCOP, OECD No. 437/2017), which can be applied using top-down or bottom-up approaches. In addition, it suggests making a corneal histomorphometric evaluation as an additional parameter in the BCOP method to differentiate materials that cause serious eye tissue damage (UN GHS Cat. 1) from materials that have reversible eye irritation effects (UN GHS Cat. 2).


Assuntos
Alternativas aos Testes com Animais , Bioensaio , Membrana Corioalantoide/irrigação sanguínea , Membrana Corioalantoide/efeitos dos fármacos , Córnea/efeitos dos fármacos , Irritantes/toxicidade , Neuropatia Óptica Tóxica , Testes de Toxicidade , Animais , Bovinos , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Embrião de Galinha , Córnea/patologia , Coelhos
18.
Lasers Med Sci ; 36(4): 903-912, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33113075

RESUMO

To assess the effectiveness of photobiomodulation therapy (PBMT) in the oral health-related quality of life (OHRQoL) of patients with head and neck cancer undergoing radiotherapy (RT), using the Oral Health Impact Profile-14 (OHIP-14) and the Patient-Reported Oral Mucositis (OM) Symptoms Scale (PROMS), and to correlate OM degree with the PROMS and OHIP-14 scores. Forty-eight patients undergoing RT for head and neck cancer were randomly assigned into two groups: PBMT group (n = 25)-daily PBMT associated with a preventive oral care program (POCP); and control group (n = 23)-receiving POCP exclusively. OHRQoL was assessed using the PROMS and OHIP-14 questionnaires. OM degrees were classified according to the World Health Organization and the National Cancer Institute scales. Assessments were performed at the 1st, 7th, 14th, 21st, and 30th RT sessions. PBMT was effective in preventing and treating severe OM. Both groups showed increased OHRQoL impacts throughout the RT sessions; however, higher impacts were observed in the control group, mainly at the final stage of treatment (21st and 30th RT sessions). Significant correlations were found between the severity of OM and PROMS scores in the total sample and the control group at all RT periods. PROMS and OM scores were positive correlated at 14th, 21st, and 30th RT sessions in the control group, suggesting that this instrument is useful in classifying OM. PBMT was effective in treating and preventing severe OM and OM-related symptoms, and with consequent positive impacts in OHRQoL in head and neck patients undergoing RT. The PROMS scale was helpful instrument for assessment of the severity of OM. Brazilian Clinical Trials database (ReBEC - RBR-5h4y4n), registered in Aug, 24th 2017.


Assuntos
Neoplasias de Cabeça e Pescoço/complicações , Neoplasias de Cabeça e Pescoço/radioterapia , Terapia com Luz de Baixa Intensidade , Estomatite/complicações , Humanos , Masculino , Pessoa de Meia-Idade , Qualidade de Vida , Estomatite/etiologia , Estomatite/radioterapia , Inquéritos e Questionários
19.
Support Care Cancer ; 29(3): 1245-1256, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32621262

RESUMO

OBJECTIVES: This study aimed to assess the cost-effectiveness of photobiomodulation therapy (PBMT) in association with a Preventive Oral Care Program (POCP) compared with POCP alone in the treatment of radiotherapy (RT)-induced oral mucositis (OM). METHODS: The cost-effectiveness was evaluated from the health provider perspective and conducted alongside a randomized, double-blind clinical trial. Participants were randomly assigned to either PBMT (n = 25) or control (n = 23) group. The PBMT group participants received PBMT associated with POCP. In the control group, patients were submitted to POCP alone. Costs were identified, quantified, and valued through observation and consultation of the hospital's financial sector database and estimated in Brazilian real and converted to international dollars using the purchasing power parity exchange rate. The incremental cost-effectiveness ratio (ICER) was estimated by considering the prevention of severe OM, interruption of RT, and oral health-related quality of life (OHRQoL) scores, measured by the OHIP-14 and patient-reported OM symptoms scale (PROMS). RESULTS: The incremental cost of PBMT was $857.35, and the cost per session was $25.69. The ICER was $ 2867.39 to avoid one case of severe OM and $ 2756.75 to prevent one interruption in RT due to OM. ICER to reduce 1 point in OHIP-14 and PROMS scores were $170.79 and $31.75, respectively. CONCLUSION: PBMT is more cost-effective than POCP alone in preventing severe OM, worsening of the OHRQoL, and RT interruptions. PBMT is a promising therapy, especially to avoid interruptions in oncological treatment. TRIAL REGISTRATION: ReBEC-RBR-5h4y4n.


Assuntos
Quimiorradioterapia/efeitos adversos , Análise Custo-Benefício/métodos , Terapia com Luz de Baixa Intensidade/métodos , Qualidade de Vida/psicologia , Estomatite/induzido quimicamente , Estomatite/prevenção & controle , Brasil , Institutos de Câncer , Método Duplo-Cego , Feminino , Humanos , Masculino
20.
Toxicol Sci ; 177(2): 316-324, 2020 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-32930792

RESUMO

Agriculture in the 21st century faces multiple challenges to produce food for the growing population using ethical/sustainable and efficient methods safely for humans and the environment. Brazil today is a world leader in terms of production of food of plant origin, both for human consumption and animal feed. Agriculture and livestock raising are critical economic activities in maintaining a positive balance in its economy. As a consequence, the registration and use of pesticides in Brazil have grown at an accelerated rate. This work shows the current situation in Brazil in terms of the prevailing laws about the registration of pesticides, with a focus on the toxicological aspects related to human health. The regulatory aspects of registration of pesticides in Brazil, the mandatory testing for evaluating pesticide toxicity, adoption of the Globally Harmonized System of Classification and Labeling of Chemicals, and recent progress toward nonanimal methods to toxicity evaluation were explored in this work. In this field, Brazil has advanced and there are opportunities and challenges. There is still much to be done and investments to be made so that Brazil can definitively consolidate its conduct within the context of a Modern Regulatory Toxicology, which has entered the 21st century.


Assuntos
Agricultura , Agroquímicos/toxicidade , Praguicidas , Animais , Brasil , Humanos
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