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1.
Mutagenesis ; 38(5): 253-263, 2023 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-37233347

RESUMO

Measurement of DNA migration in the comet assay can be done by image analysis or visual scoring. The latter accounts for 20%-25% of the published comet assay results. Here we assess the intra- and inter-investigator variability in visual scoring of comets. We include three training sets of comet images, which can be used as reference for researchers who wish to use visual scoring of comets. Investigators in 11 different laboratories scored the comet images using a five-class scoring system. There is inter-investigator variation in the three training sets of comets (i.e. coefficient of variation (CV) = 9.7%, 19.8%, and 15.2% in training sets I-III, respectively). However, there is also a positive correlation of inter-investigator scoring in the three training sets (r = 0.60). Overall, 36% of the variation is attributed to inter-investigator variation and 64% stems from intra-investigator variation in scoring between comets (i.e. the comets in training sets I-III look slightly different and this gives rise to heterogeneity in scoring). Intra-investigator variation in scoring was also assessed by repeated analysis of the training sets by the same investigator. There was larger variation when the training sets were scored over a period of six months (CV = 5.9%-9.6%) as compared to 1 week (CV = 1.3%-6.1%). A subsequent study revealed a high inter-investigator variation when premade slides, prepared in a central laboratory, were stained and scored by investigators in different laboratories (CV = 105% and 18%-20% in premade slides with comets from unexposed and hydrogen peroxide-exposed cells, respectively). The results indicate that further standardization of visual scoring is desirable. Nevertheless, the analysis demonstrates that visual scoring is a reliable way of analysing DNA migration in comets.

2.
Mutagenesis ; 38(5): 283-294, 2023 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-37228081

RESUMO

The comet assay is a simple and versatile method for measurement of DNA damage in eukaryotic cells. More specifically, the assay detects DNA migration from agarose gel-embedded nucleoids, which depends on assay conditions and the level of DNA damage. Certain steps in the comet assay procedure have substantial impact on the magnitude of DNA migration (e.g. electric potential and time of electrophoresis). Inter-laboratory variation in DNA migration levels occurs because there is no agreement on optimal assay conditions or suitable assay controls. The purpose of the hCOMET ring trial was to test potassium bromate (KBrO3) as a positive control for the formamidopyrimidine DNA glycosylase (Fpg)-modified comet assay. To this end, participating laboratories used semi-standardized protocols for cell culture (i.e. cell culture, KBrO3 exposure, and cryopreservation of cells) and comet assay procedures, whereas the data acquisition was not standardized (i.e. staining of comets and image analysis). Segregation of the total variation into partial standard deviation (SD) in % Tail DNA units indicates the importance of cell culture procedures (SD = 10.9), comet assay procedures (SD = 12.3), staining (SD = 7.9) and image analysis (SD = 0.5) on the overall inter-laboratory variation of DNA migration (SD = 18.2). Future studies should assess sources of variation in each of these steps. On the positive side, the hCOMET ring trial demonstrates that KBrO3 is a robust positive control for the Fpg-modified comet assay. In conclusion, the hCOMET ring trial has demonstrated a high reproducibility of detecting genotoxic effects by the comet assay, but inter-laboratory variation of DNA migration levels is a concern.

3.
J Toxicol Environ Health B Crit Rev ; 26(2): 67-96, 2023 02 17.
Artigo em Inglês | MEDLINE | ID: mdl-36692141

RESUMO

Several studies have been conducted to address the potential adverse health risks attributed to exposure to nanoscale materials. While in vivo studies are fundamental for identifying the relationship between dose and occurrence of adverse effects, in vitro model systems provide important information regarding the mechanism(s) of action at the molecular level. With a special focus on exposure to inhaled (nano)particulate material toxicity assessment, this review provides an overview of the available human respiratory models and exposure systems for in vitro testing, advantages, limitations, and existing investigations using models of different complexity. A brief overview of the human respiratory system, pathway and fate of inhaled (nano)particles is also presented.


Assuntos
Nanopartículas , Sistema Respiratório , Humanos , Poeira , Exposição por Inalação/efeitos adversos , Nanopartículas/toxicidade
4.
Gerontology ; 69(6): 684-693, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36538907

RESUMO

INTRODUCTION: Immunosenescence and inflammaging have been implicated in the pathophysiology of frailty. Torquetenovirus (TTV), a single-stranded DNA anellovirus, the major component of the human blood virome, shows an increased replication rate with advancing age. An elevated TTV viremia has been associated with an impaired immune function and an increased risk of mortality in the older population. The objective of this study was to analyze the relation between TTV viremia, physical frailty, and cognitive impairment. METHODS: TTV viremia was measured in 1,131 nonfrail, 45 physically frail, and 113 cognitively impaired older adults recruited in the MARK-AGE study (overall mean age 64.7 ± 5.9 years), and then the results were checked in two other independent cohorts from Spain and Portugal, including 126 frail, 252 prefrail, and 141 nonfrail individuals (overall mean age: 77.5 ± 8.3 years). RESULTS: TTV viremia ≥4log was associated with physical frailty (OR: 4.69; 95% CI: 2.06-10.67, p < 0.0001) and cognitive impairment (OR: 3.49, 95% CI: 2.14-5.69, p < 0.0001) in the MARK-AGE population. The association between TTV DNA load and frailty status was confirmed in the Spanish cohort, while a slight association with cognitive impairment was observed (OR: 1.33; 95% CI: 1.000-1.773), only in the unadjusted model. No association between TTV load and frailty or cognitive impairment was found in the Portuguese sample, although a negative association between TTV viremia and MMSE score was observed in Spanish and Portuguese females. CONCLUSIONS: These findings demonstrate an association between TTV viremia and physical frailty, while the association with cognitive impairment was observed only in the younger population from the MARK-AGE study. Further research is necessary to clarify TTV's clinical relevance in the onset and progression of frailty and cognitive decline in older individuals.


Assuntos
Disfunção Cognitiva , Fragilidade , Torque teno virus , Feminino , Idoso , Humanos , Idoso de 80 Anos ou mais , Fragilidade/epidemiologia , Torque teno virus/fisiologia , Viremia/complicações , Idoso Fragilizado/psicologia , Avaliação Geriátrica , Disfunção Cognitiva/complicações , Disfunção Cognitiva/epidemiologia
5.
Cost Eff Resour Alloc ; 20(1): 71, 2022 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-36527052

RESUMO

BACKGROUND: Governments in Latin America are constantly facing the problem of managing scarce resources to satisfy alternative needs, such as housing, education, food, and healthcare security. Those needs, combined with increasing crime levels, require financial resources to be solved. OBJECTIVE: The objective of this review was to characterizar the health system and health expenditure of a large country (Brazil) and a small country (Chile) and identify some of the challenges these two countries face in improving the health services of their population. METHODS: A literature review was conducted by searching journals, databases, and other electronic resources to identify articles and research publications describing health systems in Brazil and Chile. RESULTS: The review showed that the economic restriction and the economic cycle have an impact on the funding of the public health system. This result was true for the Brazilian health system after 2016, despite the change to a unique health system one decade earlier. In the case of Chile, there are different positions about which one is the best health system: a dual public and private or just public one. As a result, a referendum on September 4, 2022, of a new constitution, which incorporated a unique health system, was rejected. At the same time, the Government ended the copayment in the public health system in September 2022, excluding illnesses referred to the private sector. Another issue detected was the fragility of the public and private sector coverage due to the lack of funding. CONCLUSIONS: The health care system in Chile and Brazil has improved in the last decades. However, the public healthcare systems still need additional funding and efficiency improvement to respond to the growing health requirements needed from the population.

6.
Environ Res ; 203: 111827, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34363802

RESUMO

Tobacco consumption and environmental tobacco smoke (ETS) exposure remains an important public health concern. Pregnant women require particular attention as active and passive smoking during pregnancy are associated with multiple adverse perinatal outcomes. This study aimed to biochemically validate self-reported smoking and ETS exposure status among pregnant women, to more precisely ascertain its association with adverse perinatal outcomes. Data refers to 595 pregnant women who sought prenatal care in a public hospital in Porto, Portugal. A standard questionnaire on smoking and ETS-related variables was completed. Urinary cotinine (UC) concentrations were assessed by solid-phase competitive ELISA, in maternal urine samples collected on the day of delivery. The results showed that the optimal UC cut-off value to distinguish smokers from non-smokers and within non-smokers those who were exposed to ETS from those non-exposed in the third trimester of pregnancy was 74.1 ng/mL (sensitivity and specificity of 96.7% and 98.0%, respectively) and 1.6 ng/mL (sensitivity of 66.2% and specificity of 75.7%, respectively). The agreement between maternal self-reported and UC-based smoking status was very good (κ=0.919, p<0.001), but much lower for ETS exposure (κ=0.386, p<0.001). Maternal active smoking in the third trimester of pregnancy was associated with a significant decrease in birth weight, length and head circumference of 157.66 g (95% CI: -245.81, -69.52; p<0.001), 0.78 cm (95% CI: -1.22, -0.34; p=0.001) and 0.39 cm (95% CI: -0.70, -0.07; p=0.016), respectively. Maternal ETS exposure in the third trimester of pregnancy was associated with a non-significant increase in birth weight of 38.37 g (95% CI: -28.91, 105.64; p=0.263). Furthermore, maternal smoking cessation was associated with the increase of approximately 172 g in birth weight (95% CI: 50.00, 293.19). As such, there is an urgent need for increased public health awareness campaigns to encourage smoking cessation during pregnancy, in order to improve perinatal outcomes.


Assuntos
Cotinina , Poluição por Fumaça de Tabaco , Estudos Transversais , Feminino , Humanos , Exposição Materna/estatística & dados numéricos , Gravidez , Fumar , Poluição por Fumaça de Tabaco/análise , Poluição por Fumaça de Tabaco/estatística & dados numéricos
7.
Adv Exp Med Biol ; 1357: 303-350, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35583650

RESUMO

Iron oxide nanoparticles (ION), with unique magnetic properties, have attracted huge scientific attention for a wide variety of uses, mostly in the biomedical field, due to their high biocompatibility, ability to cross biological membranes, appropriate surface architecture and easy conjugation with targeting ligands. Their current applications include diagnostic imaging, cell labelling, site-directed drug delivery and anticancer hyperthermia therapy. The ION surface may be modified by coating with different materials, aiming to stabilize the nanoparticles in different environments, to allow biomolecule binding favouring surface attachments with several molecules, and to prolong the recognition time by the immune system. Although the potential benefits of ION are considerable, and more and more ION are being manufactured to meet the demands of the rapidly proliferating field of nanomedicine, there is an urgent need to define their toxicological profile in order to avoid any potential health risks associated with their exposure and to reach optimal benefits of their use. The purpose of this chapter is to de-scribe the current knowledge on the ION toxicological features, addressing their structure and physicochemical characteristics, main exposure pathways and toxicokinetic aspects, interaction with cells, and their toxic effects, with special attention to those at the cellular and molecular level.


Assuntos
Nanomedicina , Nanopartículas , Sistemas de Liberação de Medicamentos/efeitos adversos , Compostos Férricos/química , Compostos Férricos/uso terapêutico , Compostos Férricos/toxicidade , Nanopartículas Magnéticas de Óxido de Ferro , Magnetismo , Nanopartículas/química , Nanopartículas/toxicidade
8.
Drug Chem Toxicol ; 45(3): 1066-1072, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-32811197

RESUMO

The Brazil nut (Bertholletia excelsa, H.B.K.) originating from the Amazon region is one of the richest known sources of selenium (Se), a micronutrient that is essential and required for optimal physiological functioning. This mineral presents several health benefits, including improvement of the redox cellular status and maintenance of genomic stability. Knowing that type 2 diabetes mellitus (T2D) is strongly linked to oxidative stress and consequently DNA damage, the aim of this study was to assess the ex vivo antioxidative effects of Se through Brazil nut consumption and its potential in preventing oxidative DNA damage induced by H2O2. In order to accomplish this, the Comet assay (single-cell gel electrophoresis) was used to measure DNA damage in peripheral blood cells harvested before and after supplementation with Brazil nut. Comet assay was also applied ex vivo to measure the potential of Se to prevent oxidative damage to DNA induced by H2O2 in blood of type 2 diabetes patients collected before and after six months of supplementation with Brazil nut. We found that supplementation with Brazil nuts significantly increased serum Se levels. Furthermore, we observed a significant increase in fasting blood glucose after six months of consuming Brazil nuts; however, no significant effect was observed on the levels of glycated hemoglobin. Finally, we noticed that the cells were more resistant to H2O2-induced DNA damage after six months of supplementation with Brazil nut. Thus, consumption of Brazil nuts could decrease oxidative DNA damage in T2D patients, probably through the antioxidative effects of Se.


Assuntos
Bertholletia , Diabetes Mellitus Tipo 2 , Selênio , Humanos , Peróxido de Hidrogênio/farmacologia , Estresse Oxidativo , Selênio/farmacologia
9.
Int J Mol Sci ; 23(9)2022 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-35563333

RESUMO

Depression is a very prevalent and complex disease. This condition is associated with a high rate of relapse, making its treatment a challenge. Thus, an intensive investigation of this disease and its treatment is necessary. In this work, through cell viability assays (MTT and neutral red assays) and alkaline comet assays, we aimed to test the induction of stress in human SH-SY5Y cells through the application of hydrocortisone and hydrogen peroxide and to test the reversal or attenuation of this stress through the application of mirtazapine to the cells. Our results demonstrated that hydrogen peroxide, and not hydrocortisone, can induce cellular stress, as evidenced by DNA damage and a global cellular viability reduction, which were alleviated by the antidepressant mirtazapine. The establishment of a cellular model of depression through stress induction is important to study new possibilities of treatment of this disease using cell cultures.


Assuntos
Depressão , Peróxido de Hidrogênio , Linhagem Celular Tumoral , Sobrevivência Celular , Depressão/tratamento farmacológico , Humanos , Peróxido de Hidrogênio/farmacologia , Mirtazapina/farmacologia , Mirtazapina/uso terapêutico , Estresse Oxidativo
10.
Int J Mol Sci ; 23(5)2022 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-35269878

RESUMO

Considering the increasing emergence of new contaminants, such as nanomaterials, mixing with legacy contaminants, including metal(loid)s, it becomes imperative to understand the toxic profile resulting from these interactions. This work aimed at assessing and comparing the individual and combined hepatotoxic and neurotoxic potential of titanium dioxide nanoparticles (TiO2NPs 0.75-75 mg/L), cerium oxide nanoparticles (CeO2NPs 0.075-10 µg/L), arsenic (As 0.01-2.5 mg/L), and mercury (Hg 0.5-100 mg/L) on human hepatoma (HepG2) and neuroblastoma (SH-SY5Y) cells. Viability was assessed through WST-1 (24 h) and clonogenic (7 days) assays and it was affected in a dose-, time- and cell-dependent manner. Higher concentrations caused greater toxicity, while prolonged exposure caused inhibition of cell proliferation, even at low concentrations, for both cell lines. Cell cycle progression, explored by flow cytometry 24 h post-exposure, revealed that TiO2NPs, As and Hg but not CeO2NPs, changed the profiles of SH-SY5Y and HepG2 cells in a dose-dependent manner, and that the cell cycle was, overall, more affected by exposure to mixtures. Exposure to binary mixtures revealed either potentiation or antagonistic effects depending on the composition, cell type and time of exposure. These findings prove that joint toxicity of contaminants cannot be disregarded and must be further explored.


Assuntos
Arsênio , Cério , Mercúrio , Nanopartículas , Síndromes Neurotóxicas , Arsênio/toxicidade , Cério/toxicidade , Humanos , Mercúrio/toxicidade , Nanopartículas/toxicidade , Titânio/toxicidade
11.
Int J Mol Sci ; 23(8)2022 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-35457096

RESUMO

High-energy industrial processes have been associated with particle release into workplace air that can adversely affect workers' health. The present study assessed the toxicity of incidental fine (PGFP) and nanoparticles (PGNP) emitted from atmospheric plasma (APS) and high-velocity oxy-fuel (HVOF) thermal spraying. Lactate dehydrogenase (LDH) release, 2-(4-nitrophenyl)-2H-5-tetrazolio]-1,3-benzene disulfonate (WST-1) metabolisation, intracellular reactive oxygen species (ROS) levels, cell cycle changes, histone H2AX phosphorylation (γ-H2AX) and DNA damage were evaluated in human alveolar epithelial cells at 24 h after exposure. Overall, HVOF particles were the most cytotoxic to human alveolar cells, with cell viability half-maximal inhibitory concentration (IC50) values of 20.18 µg/cm2 and 1.79 µg/cm2 for PGFP and PGNP, respectively. Only the highest tested concentration of APS-PGFP caused a slight decrease in cell viability. Particle uptake, cell cycle arrest at S + G2/M and γ-H2AX augmentation were observed after exposure to all tested particles. However, higher levels of γ-H2AX were found in cells exposed to APS-derived particles (~16%), while cells exposed to HVOF particles exhibited increased levels of oxidative damage (~17% tail intensity) and ROS (~184%). Accordingly, APS and HVOF particles seem to exert their genotoxic effects by different mechanisms, highlighting that the health risks of these process-generated particles at industrial settings should not be underestimated.


Assuntos
Células Epiteliais Alveolares , Dano ao DNA , Células Epiteliais Alveolares/metabolismo , Sobrevivência Celular , Células Epiteliais/metabolismo , Humanos , Estresse Oxidativo , Tamanho da Partícula , Espécies Reativas de Oxigênio/metabolismo
12.
Int J Environ Health Res ; 32(7): 1500-1512, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33685302

RESUMO

Dermatophagoides pteronyssinus and Dermatophagoides farinae are the most common House Dust Mite (HDM) species in home environments worldwide and responsible for HDM allergy. Since the prevalence of HDM-related clinical conditions is linked to exposure to the mite itself, the detection of HDM in the human households gains importance. We aimed to develop a fast and accessible multiplex PCR to detect and distinguish two relevant HDM species in house dust. New primers were designed, and sensitivity analysis was performed. Sequencing of PCR products was also performed to confirm the method's specificity. The limit of detection of the multiplex PCR for both species was as low as 30 pg µL-1. The application of the multiplex PCR to dust samples also resulted in the identification of both species with high sensitivity. The protocol required small amount of template, reagents and a short reaction time thus presenting an alternative to classically used techniques for HDM identification.


Assuntos
Reação em Cadeia da Polimerase Multiplex , Pyroglyphidae , Alérgenos/análise , Animais , Poeira/análise , Humanos , Prevalência
13.
Epidemiology ; 32(4): 487-498, 2021 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-33935136

RESUMO

BACKGROUND: There is strong evidence concerning the impact of heat stress on mortality, particularly from high temperatures. However, few studies to our knowledge emphasize the importance of hot nights, which may prevent necessary nocturnal rest. OBJECTIVES: In this study, we use hot-night duration and excess to predict daily cause-specific mortality in summer, using multiple cities across Southern Europe. METHODS: We fitted time series regression models to summer cause-specific mortality, including natural, respiratory, and cardiovascular causes, in 11 cities across four countries. We included a distributed lag nonlinear model with lags up to 7 days for hot night duration and excess adjusted by daily mean temperature. We summarized city-specific associations as overall-cumulative exposure-response curves at the country level using meta-analysis. RESULTS: We found positive but generally nonlinear associations between relative risk (RR) of cause-specific mortality and duration and excess of hot nights. RR of duration associated with nonaccidental mortality in Portugal was 1.29 (95% confidence interval [CI] = 1.07, 1.54); other associations were imprecise, but we also found positive city-specific estimates for Rome and Madrid. Risk of hot-night excess ranged from 1.12 (95% CI = 1.05, 1.20) for France to 1.37 (95% CI = 1.26, 1.48) for Portugal. Risk estimates for excess were consistently higher than for duration. CONCLUSIONS: This study provides new evidence that, over a wider range of locations, hot night indices are strongly associated with cause-specific deaths. Modeling the impact of thermal characteristics during summer nights on mortality could improve decisionmaking for preventive public health strategies.


Assuntos
Temperatura Alta , Mortalidade , Cidades , Europa (Continente)/epidemiologia , França , Humanos , Estações do Ano
14.
Environ Res ; 194: 110728, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33444608

RESUMO

Recycling of electric and electronic waste products (e-waste) which amounted to more than 50 million metric tonnes per year worldwide is a massive and global operation. Unfortunately, an estimated 70-80% of this waste has not been properly managed because the waste went from developed to low-income countries to be dumped into landfills or informally recycled. Such recycling has been carried out either directly on landfill sites or in small, often family-run recycling shops without much regulations or oversights. The process traditionally involved manual dismantling, cleaning with hazardous solvents, burning and melting on open fires, etc., which would generate a variety of toxic substances and exposure/hazards to applicators, family members, proximate residents and the environment. The situation clearly calls for global responsibility to reduce the impact on human health and the environment, especially in developing countries where poor residents have been shouldering the hazardous burden. On the other hand, formal e-waste recycling has been mainly conducted in small scales in industrialized countries. Whether the latter process would impose less risk to populations and environment has not been determined yet. Therefore, the main objectives of this review are: 1. to address current trends and emerging threats of not only informal but also formal e-waste management practices, and 2. to propose adequate measures and interventions. A major recommendation is to conduct independent surveillance of compliance with e-waste trading and processing according to the Basel Ban Amendment. The recycling industry needs to be carefully evaluated by joint effort from international agencies, producing industries and other stakeholders to develop better processes. Subsequent transition to more sustainable and equitable e-waste management solutions should result in more effective use of natural resources, and in prevention of adverse effects on health and the environment.


Assuntos
Resíduo Eletrônico , Gerenciamento de Resíduos , Resíduo Eletrônico/análise , Eletrônica , Humanos , Reciclagem
15.
Int J Mol Sci ; 22(16)2021 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-34445265

RESUMO

Standard toxicity tests might not be fully adequate for evaluating nanomaterials since their unique features are also responsible for unexpected interactions. The in vitro cytokinesis-block micronucleus (CBMN) test is recommended for genotoxicity testing, but cytochalasin-B (Cyt-B) may interfere with nanoparticles (NP), leading to inaccurate results. Our objective was to determine whether Cyt-B could interfere with MN induction by TiO2 NP in human SH-SY5Y cells, as assessed by CBMN test. Cells were treated for 6 or 24 h, according to three treatment options: co-treatment with Cyt-B, post-treatment, and delayed co-treatment. Influence of Cyt-B on TiO2 NP cellular uptake and MN induction as evaluated by flow cytometry (FCMN) were also assessed. TiO2 NP were significantly internalized by cells, both in the absence and presence of Cyt-B, indicating that this chemical does not interfere with NP uptake. Dose-dependent increases in MN rates were observed in CBMN test after co-treatment. However, FCMN assay only showed a positive response when Cyt-B was added simultaneously with TiO2 NP, suggesting that Cyt-B might alter CBMN assay results. No differences were observed in the comparisons between the treatment options assessed, suggesting they are not adequate alternatives to avoid Cyt-B interference in the specific conditions tested.


Assuntos
Citocinese/efeitos dos fármacos , Micronúcleos com Defeito Cromossômico , Nanopartículas/efeitos adversos , Titânio/efeitos adversos , Linhagem Celular Tumoral , Citocalasina B/farmacologia , Relação Dose-Resposta a Droga , Humanos , Titânio/farmacologia
16.
Mutagenesis ; 35(4): 341-348, 2020 09 12.
Artigo em Inglês | MEDLINE | ID: mdl-32319518

RESUMO

The comet assay is a popular assay in biomonitoring studies. DNA strand breaks (or unspecific DNA lesions) are measured using the standard comet assay. Oxidative stress-generated DNA lesions can be measured by employing DNA repair enzymes to recognise oxidatively damaged DNA. Unfortunately, there has been a tendency to fail to report results from assay controls (or maybe even not to employ assay controls). We believe this might have been due to uncertainty as to what really constitutes a positive control. It should go without saying that a biomonitoring study cannot have a positive control group as it is unethical to expose healthy humans to DNA damaging (and thus potentially carcinogenic) agents. However, it is possible to include assay controls in the analysis (here meant as a cryopreserved sample of cells i.e. included in each experiment as a reference sample). In the present report we tested potassium bromate (KBrO3) as a positive comet assay control for the formamidopyrimidine DNA glycosylase (Fpg)-modified comet assay. Ten laboratories used the same procedure for treatment of monocytic THP-1 cells with KBrO3 (0.5, 1.5 and 4.5 mM for 1 h at 37°C) and subsequent cryopreservation. Results from one laboratory were excluded in the statistical analysis because of technical issues in the Fpg-modified comet assay. All other laboratories found a concentration-response relationship in cryopreserved samples (regression coefficients from 0.80 to 0.98), although with different slopes ranging from 1.25 to 11.9 Fpg-sensitive sites (%DNA in tail) per 1 mM KBrO3. Our results demonstrate that KBrO3 is a suitable positive comet assay control.


Assuntos
Bromatos/toxicidade , Ensaio Cometa/normas , Dano ao DNA , Monócitos/efeitos dos fármacos , Monitoramento Biológico , DNA/efeitos dos fármacos , DNA/metabolismo , DNA-Formamidopirimidina Glicosilase , Humanos , Monócitos/metabolismo , Estresse Oxidativo , Células THP-1
17.
Environ Res ; 184: 109297, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32155489

RESUMO

The ceramic industry is an industrial sector of great impact in the global economy that has been benefiting from advances in materials and processing technologies. Ceramic manufacturing has a strong potential for airborne particle formation and emission, namely of ultrafine particles (UFP) and nanoparticles (NP), meaning that workers of those industries are at risk of potential exposure to these particles. At present, little is known on the impact of engineered nanoparticles (ENP) on the environment and human health and no established Occupational Exposure Limits (OEL) or specific regulations to airborne nanoparticles (ANP) exposure exist raising concerns about the possible consequences of such exposure. In this paper, we provide an overview of the current knowledge on occupational exposure to NP in the ceramic industry and their impact on human health. Possible sources and exposure scenarios, a summary of the existing methods for evaluation and monitoring of ANP in the workplace environment and proposed Nano Reference Values (NRV) for different classes of NP are presented. Case studies on occupational exposure to ANP generated at different stages of the ceramic manufacturing process are described. Finally, the toxicological potential of intentional and unintentional ANP that have been identified in the ceramic industry workplace environment is discussed based on the existing evidence from in vitro and in vivo inhalation toxicity studies.


Assuntos
Poluentes Ocupacionais do Ar , Nanopartículas , Exposição Ocupacional , Poluentes Ocupacionais do Ar/análise , Poluentes Ocupacionais do Ar/toxicidade , Cerâmica/toxicidade , Monitoramento Ambiental , Humanos , Exposição por Inalação/efeitos adversos , Exposição por Inalação/análise , Nanopartículas/toxicidade , Exposição Ocupacional/análise , Tamanho da Partícula
18.
Environ Res ; 186: 109470, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32305678

RESUMO

BACKGROUND: The presence of pesticides in honey and related products is an increasing concern for consumers and producers, although there is lack of data on the current burden of exposure of the general human population through these products. We present a protocol for a systematic review and meta-analysis of contamination to insecticides, herbicides and fungicides of products from honeybees, and an estimation of how much the consumption of these products contributes to the ADI (Acceptable Daily Intake) of selected substances. OBJECTIVES: We aim to systematically review and meta-analyse studies on the contamination to plant protection products in honey, royal jelly, beeswax and propolis, applying the Navigation Guide and WHO-ILO systematic review methodology as an organizing framework. DATA SOURCES: We will search electronic academic databases for potentially relevant records from PubMed, TOXNET and EMBASE. We will include quantitative studies analysing the contamination from insecticides, herbicides and fungicides in honey, propolis, royal jelly and beeswax. In particular, we will evaluate the presence of the following substances and classes of pesticides: Glyphosate, Chlorpyrifos, pyrethroid and neonicotinoid pesticides, fungicides and acaricides. STUDY APPRAISAL AND SYNTHESIS METHODS: At least two authors will independently screen titles and abstracts at a first stage of review, and full texts at a second stage, of potentially eligible records against the eligibility criteria; data extraction of included studies will then be performed by at least two authors, in blind. At least two authors will assess risk of bias and the quality of evidence, using the most suited tools currently available. The data on prevalence of contaminated samples and concentration of pesticides in the products will be combined using meta-analysis: when more than three studies reporting the necessary measures to fit the models are available, meta-analysis will be performed separately by product and by exposure; otherwise, weighted descriptive analysis will be performed. We will report the results using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines (PRISMA).


Assuntos
Mel , Inseticidas , Doenças Profissionais , Exposição Ocupacional , Resíduos de Praguicidas , Animais , Abelhas , Humanos , Exposição Ocupacional/análise , Organização Mundial da Saúde
19.
Environ Res ; 181: 108947, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31767353

RESUMO

The bioburden in a Hospital building originates not only from patients, visitors and staff, but is also disseminated by several indoor hospital characteristics and outdoor environmental sources. This study intends to assess the exposure to bioburden in one central Hospital with a multi-approach protocol using active and passive sampling methods. The microbial contamination was also characterized through molecular tools for toxigenic species, antifungal resistance and mycotoxins and endotoxins profile. Two cytotoxicity assays (MTT and resazurin) were conducted with two cell lines (Calu-3 and THP-1), and in vitro pro-inflammatory potential was assessed in THP-1 cell line. Out of the 15 sampling locations 33.3% did not comply with Portuguese legislation regarding bacterial contamination, whereas concerning fungal contamination 60% presented I/O > 1. Toxigenic fungal species were observed in 27% of the sampled rooms (4 out of 15) and qPCR analysis successfully amplified DNA from the Aspergillus sections Flavi and Fumigati, although mycotoxins were not detected. Growth of distinct fungal species was observed on Sabouraud dextrose agar with triazole drugs, such as Aspergillus section Versicolores on 1 mg/L VORI. The highest concentrations of endotoxins were found in settled dust samples and ranged from 5.72 to 23.0 EU.mg-1. While a considerable cytotoxic effect (cell viability < 30%) was observed in one HVAC filter sample with Calu-3 cell line, it was not observed with THP-1 cell line. In air samples a medium cytotoxic effect (61-68% cell viability) was observed in 3 out of 15 samples. The cytokine responses produced a more potent average cell response (46.8 ± 12.3 ρg/mL IL-1ß; 90.8 ± 58.5 ρg/mL TNF-α) on passive samples than air samples (25.5 ± 5.2 ρg/mL IL-1ß and of 19.4 ± 5.2 ρg/mL TNF-α). A multi-approach regarding parameters to assess, sampling and analysis methods should be followed to characterize the biorburden in the Hospital indoor environment. This study supports the importance of considering exposure to complex mixtures in indoor environments.


Assuntos
Microbiologia do Ar , Poluição do Ar em Ambientes Fechados , Exposição Ambiental/estatística & dados numéricos , Micotoxinas , Poeira , Monitoramento Ambiental , Fungos , Humanos
20.
Global Health ; 16(1): 64, 2020 07 16.
Artigo em Inglês | MEDLINE | ID: mdl-32677998

RESUMO

BACKGROUND: Accelerated globalisation has substantially contributed to the rise of emerging markets worldwide. The G7 and Emerging Markets Seven (EM7) behaved in significantly different macroeconomic ways before, during, and after the 2008 Global Crisis. Average real GDP growth rates remained substantially higher among the EM7, while unemployment rates changed their patterns after the crisis. Since 2017, however, approximately one half of the worldwide economic growth is attributable to the EM7, and only a quarter to the G7. This paper aims to analyse the association between the health spending and real GDP growth in the G7 and the EM7 countries. RESULTS: In terms of GDP growth, the EM7 exhibited a higher degree of resilience during the 2008 crisis, compared to the G7. Unemployment in the G7 nations was rising significantly, compared to pre-recession levels, but, in the EM7, it remained traditionally high. In the G7, the austerity (measured as a percentage of GDP) significantly decreased the public health expenditure, even more so than in the EM7. Out-of-pocket health expenditure grew at a far more concerning pace in the EM7 compared to the G7 during the crisis, exposing the vulnerability of households living close to the poverty line. Regression analysis demonstrated that, in the G7, real GDP growth had a positive impact on out-of-pocket expenditure, measured as a percentage of current health expenditure, expressed as a percentage of GDP (CHE). In the EM7, it negatively affected CHE, CHE per capita, and out-of-pocket expenditure per capita. CONCLUSION: The EM7 countries demonstrated stronger endurance, withstanding the consequences of the crisis as compared to the G7 economies. Evidence of this was most visible in real growth and unemployment rates, before, during and after the crisis. It influenced health spending patterns in both groups, although they tended to diverge instead of converge in several important areas.


Assuntos
Custos de Cuidados de Saúde , Saúde Pública , Produto Interno Bruto , Gastos em Saúde , Instalações de Saúde , Humanos , Pobreza
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