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1.
Proc Biol Sci ; 291(2020): 20232617, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38593844

RESUMO

When populations repeatedly adapt to similar environments they can evolve similar phenotypes based on shared genetic mechanisms (parallel evolution). The likelihood of parallel evolution is affected by demographic history, as it depends on the standing genetic variation of the source population. The three-spined stickleback (Gasterosteus aculeatus) repeatedly colonized and adapted to brackish and freshwater. Most parallel evolution studies in G. aculeatus were conducted at high latitudes, where freshwater populations maintain connectivity to the source marine populations. Here, we analysed southern and northern European marine and freshwater populations to test two hypotheses. First, that southern European freshwater populations (which currently lack connection to marine populations) lost genetic diversity due to bottlenecks and inbreeding compared to their northern counterparts. Second, that the degree of genetic parallelism is higher among northern than southern European freshwater populations, as the latter have been subjected to strong drift due to isolation. The results show that southern populations exhibit lower genetic diversity but a higher degree of genetic parallelism than northern populations. Hence, they confirm the hypothesis that southern populations have lost genetic diversity, but this loss probably happened after they had already adapted to freshwater conditions, explaining the high degree of genetic parallelism in the south.


Assuntos
Água Doce , Smegmamorpha , Animais , Smegmamorpha/genética , Endogamia , Variação Genética
2.
Oral Dis ; 2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38297810

RESUMO

OBJECTIVE: To analyze the immunohistochemical expression of YAP and its correlation with markers involved in cell proliferation and apoptosis in benign epithelial odontogenic lesions. STUDY DESIGN: The sample consisted of 95 cases of odontogenic lesions (25 dentigerous cysts, 30 non-syndromic odontogenic keratocysts, 30 conventional ameloblastomas, and 10 unicystic ameloblastomas) and 10 dental follicles used as normal odontogenic tissue. The histological sections were submitted to immunohistochemistry with YAP, cyclin D1, Ki-67, and Bcl-2 antibodies. Immunoexpression was analyzed qualitatively and quantitatively using an adapted method. The collected data were analyzed descriptively and statistically (p ≤ 0.05). RESULTS: The highest YAP expression was observed in odontogenic keratocysts, followed by unicystic ameloblastomas and conventional ameloblastomas, which exhibited moderate immunoreactivity predominantly in peripheral cells. Furthermore, significant differences in YAP immunoexpression were observed between the groups analyzed, with significant positive correlations between YAP and cyclin D1 in dentigerous cysts and unicystic ameloblastomas and between YAP and Ki-67 in unicystic ameloblastomas (p < 0.05). However, there were no statistically significant correlations between YAP and Bcl-2 immunoexpression in the groups studied. CONCLUSION: YAP may influence epithelial cell proliferation in odontogenic cysts and tumors, suggesting its possible participation in the progression of the odontogenic lesions studied.

3.
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.

4.
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.

5.
Mutagenesis ; 38(5): 273-282, 2023 10 14.
Artigo em Inglês | MEDLINE | ID: mdl-37357800

RESUMO

The comet assay is widely used in biomonitoring studies for the analysis of DNA damage in leukocytes and peripheral blood mononuclear cells. Rather than processing blood samples directly, it can be desirable to cryopreserve whole blood or isolated cells for later analysis by the comet assay. However, this creates concern about artificial accumulation of DNA damage during cryopreservation. In this study, 10 laboratories used standardized cryopreservation and thawing procedures of monocytic (THP-1) or lymphocytic (TK6) cells. Samples were cryopreserved in small aliquots in 50% foetal bovine serum, 40% cell culture medium, and 10% dimethyl sulphoxide. Subsequently, cryopreserved samples were analysed by the standard comet assay on three occasions over a 3-year period. Levels of DNA strand breaks in THP-1 cells were increased (four laboratories), unaltered (four laboratories), or decreased (two laboratories) by long-term storage. Pooled analysis indicates only a modest positive association between storage time and levels of DNA strand breaks in THP-1 cells (0.37% Tail DNA per year, 95% confidence interval: -0.05, 0.78). In contrast, DNA strand break levels were not increased by cryopreservation in TK6 cells. There was inter-laboratory variation in levels of DNA strand breaks in THP-1 cells (SD = 3.7% Tail DNA) and TK6 reference sample cells (SD = 9.4% Tail DNA), whereas the intra-laboratory residual variation was substantially smaller (i.e. SD = 0.4%-2.2% Tail DNA in laboratories with the smallest and largest variation). In conclusion, the study shows that accumulation of DNA strand breaks in cryopreserved mononuclear blood cell lines is not a matter of concern.


Assuntos
Dano ao DNA , Leucócitos Mononucleares , Ensaio Cometa/métodos , Leucócitos Mononucleares/metabolismo , Criopreservação/métodos , DNA/metabolismo
6.
Mutagenesis ; 38(5): 264-272, 2023 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-37357815

RESUMO

The formamidopyrimidine DNA glycosylase (Fpg)-modified comet assay is widely used for the measurement of oxidatively generated damage to DNA. However, there has not been a recommended long-term positive control for this version of the comet assay. We have investigated potassium bromate as a positive control for the Fpg-modified comet assay because it generates many Fpg-sensitive sites with a little concurrent generation of DNA strand breaks. Eight laboratories used the same procedure for the treatment of monocytic THP-1 cells with potassium bromate (0, 0.5, 1.5, and 4.5 mM) and subsequent cryopreservation in a freezing medium consisting of 50% foetal bovine serum, 40% RPMI-1640 medium, and 10% dimethyl sulphoxide. The samples were analysed by the Fpg-modified comet assay three times over a 3-year period. All laboratories obtained a positive concentration-response relationship in cryopreserved samples (linear regression coefficients ranging from 0.79 to 0.99). However, there was a wide difference in the levels of Fpg-sensitive sites between the laboratory with the lowest (4.2% Tail DNA) and highest (74% Tail DNA) values in THP-1 cells after exposure to 4.5 mM KBrO3. In an attempt to assess sources of inter-laboratory variation in Fpg-sensitive sites, comet images from one experiment in each laboratory were forwarded to a central laboratory for visual scoring. There was high consistency between measurements of %Tail DNA values in each laboratory and the visual score of the same comets done in the central laboratory (r = 0.98, P < 0.001, linear regression). In conclusion, the results show that potassium bromate is a suitable positive comet assay control.

7.
BMC Endocr Disord ; 23(1): 30, 2023 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-36732722

RESUMO

PURPOSE: Metabolic syndrome is a risk factor for several diseases. The relationship between metabolic syndrome and hypogonadism is well known. Our objetive is to assess whether a low carbohydrate diet can increase total serum testosterone and improve erectile function in hypogonadal men with metabolic syndrome. METHODS: An open label randomized clinical trial was conducted comparing a low carbohydrate diet and controls, during three months, in hypogonadal men with metabolic syndrome. Anthropometric measurements were evaluated as well as total serum testosterone levels, and symptoms of hypogonadism, using the ADAM and AMS scores, and sexual function using IIEF-5 score. RESULTS: Eighteen men were evaluated. Anthropometric measures were improved only in low carbohydrate diet group. The intervention group also had a statistically increase in IIEF-5 score and a significant reduction in AMS and ADAM scores (p < 0.001). The increase in serum total testosterone levels was statistically significant in the low carbohydrate group compared to the control group as well as calculated free testosterone (p < 0.001). CONCLUSIONS: Low carbohydrate diet may increase serum levels of testosterone and improve erectile function in hypogonadal men with metabolic syndrome. However, larger studies are necessary to strongly prove the effectiveness of low carbohydrate diet in treating male hypogonadism.


Assuntos
Disfunção Erétil , Hipogonadismo , Síndrome Metabólica , Masculino , Humanos , Disfunção Erétil/etiologia , Síndrome Metabólica/complicações , Testosterona , Hipogonadismo/complicações , Dieta com Restrição de Carboidratos
8.
Mar Drugs ; 21(3)2023 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-36976215

RESUMO

Triple-negative breast cancer (TNBC) represents an aggressive subtype of breast cancer (BC) with a typically poorer prognosis than other subtypes of BC and limited therapeutic options. Therefore, new drugs would be particularly welcome to help treat TNBC. Preussin, isolated from the marine sponge-associated fungus, Aspergillus candidus, has shown the potential to reduce cell viability and proliferation as well as to induce cell death and cell cycle arrest in 2D cell culture models. However, studies that better mimic the tumors in vivo, such as 3D cell cultures, are needed. Here, we studied the effects of preussin in the MDA-MB-231 cell line, comparing 2D and 3D cell cultures, using ultrastructural analysis and the MTT, BrdU, annexin V-PI, comet (alkaline and FPG modified versions), and wound healing assays. Preussin was found to decrease cell viability, both in 2D and 3D cell cultures, in a dose-dependent manner, impair cell proliferation, and induce cell death, therefore excluding the hypothesis of genotoxic properties. The cellular impacts were reflected by ultrastructural alterations in both cell culture models. Preussin also significantly inhibited the migration of MDA-MB-231 cells. The new data expanded the knowledge on preussin actions while supporting other studies, highlighting its potential as a molecule or scaffold for the development of new anticancer drugs against TNBC.


Assuntos
Neoplasias de Mama Triplo Negativas , Humanos , Neoplasias de Mama Triplo Negativas/patologia , Linhagem Celular Tumoral , Células MDA-MB-231 , Anisomicina , Proliferação de Células
9.
Int J Mol Sci ; 24(14)2023 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-37511482

RESUMO

Nanotechnology and the incorporation of nanomaterials (NM) into everyday products help to solve problems in society and improve the quality of life, allowing for major advances in the technological, industrial, and medical fields [...].


Assuntos
Nanoestruturas , Qualidade de Vida , Humanos , Nanoestruturas/toxicidade , Nanotecnologia
10.
J Pediatr Gastroenterol Nutr ; 75(1): 104-109, 2022 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-35578384

RESUMO

OBJECTIVES: Data on multidisciplinary programs dedicated to home parenteral nutrition (HPN) in Latin America are limited. This study describes the results of the first multidisciplinary pediatric intestinal rehabilitation program for HPN at a public tertiary hospital in Brazil. METHODS: We retrospectively reviewed patients aged 0-18 years with intestinal failure (IF) who required parenteral nutrition (PN) for >60 days between January/2014 and December/2020. RESULTS: Fifty-four patients were discharged on HPN (15 achieved enteral autonomy, 34 continued on HPN at the end of the study, 1 underwent intestinal transplantation, and 4 died). The median (IQR) age at the study endpoint of patients who achieved enteral autonomy was 14.1 (9.7-19) versus 34.7 (20.4-53.9) months in those who did not achieve enteral autonomy. Overall prevalence of catheter-related thrombosis was 66.7% and catheter-related bloodstream infection rate was 0.39/1000 catheter-days. Intestinal failure-associated liver disease (IFALD) was present in 24% of all patients; none of the patients who achieved enteral autonomy had IFALD. All patients showed significant improvement in anthropometric parameters during the HPN period. The sociodemographic characteristics of the patients' family members were mothers less than 20 years old (7.5%), schooling time more than 10 years (55.5%), and household income between 1 and 3 times the minimum wage (64.8%). The 5-year survival rate for HPN is 90%, and 27.7% of patients achieve enteral autonomy. CONCLUSION: The treatment of pediatric patients with IF followed by a multidisciplinary pediatric intestinal rehabilitation program with HPN is feasible and safe in the Brazilian public health system.


Assuntos
Enteropatias , Hepatopatias , Nutrição Parenteral no Domicílio , Adulto , Brasil , Criança , Humanos , Enteropatias/etiologia , Enteropatias/terapia , Hepatopatias/etiologia , Nutrição Parenteral no Domicílio/efeitos adversos , Estudos Retrospectivos , Adulto Jovem
11.
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
12.
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
13.
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
14.
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
15.
Molecules ; 26(14)2021 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-34299562

RESUMO

Fucoxanthin (Fx) is a carotenoid derived from marine organisms that exhibits anticancer activities. However, its role as a potential drug adjuvant in breast cancer (BC) treatment is still poorly explored. Firstly, this study investigated the cytotoxic effects of Fx alone and combined with doxorubicin (Dox) and cisplatin (Cis) on a panel of 2D-cultured BC cell lines (MCF7, SKBR3 and MDA-MB-231) and one non-tumoral cell line (MCF12A). Fucoxanthin induced cytotoxicity against all the cell lines and potentiated Dox cytotoxic effects towards the SKBR3 and MDA-MB-231 cells. The combination triggering the highest cytotoxicity (Fx 10 µM + Dox 1 µM in MDA-MB-231) additionally showed significant induction of cell death and genotoxic effects, relative to control. In sequence, the same combination was tested on 3D cultures using a multi-endpoint approach involving bioactivity assays and microscopy techniques. Similar to 2D cultures, the combination of Fx and Dox showed higher cytotoxic effects on 3D cultures compared to the isolated compounds. Furthermore, this combination increased the number of apoptotic cells, decreased cell proliferation, and caused structural and ultrastructural damages on the 3D models. Overall, our findings suggest Fx has potential to become an adjuvant for Dox chemotherapy regimens in BC treatment.


Assuntos
Adjuvantes Farmacêuticos/farmacologia , Antineoplásicos/farmacologia , Neoplasias da Mama/tratamento farmacológico , Cisplatino/farmacologia , Doxorrubicina/farmacologia , Xantofilas/farmacologia , Técnicas de Cultura de Células , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sinergismo Farmacológico , Feminino , Humanos
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 ; 178: 108647, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31450147

RESUMO

Despite physical exercise provides numerous health benefits, outdoor exercisers are frequently exposed to traffic-related air pollutants (TRAP) known to be associated with respiratory and cardiovascular diseases. The aim of this systematic review was to investigate the effects of TRAP exposure, specifically particulate matter and nitrogen dioxide (NO2), during outdoor exercise on cardio-respiratory health effects. Systematic database searches of PubMed, Web of Science, Scopus and Medline were performed by two researchers to identify peer-reviewed studies from 2000 to 2018. Combinations of keywords related to cardio-respiratory health effects, physical exercise and ambient air pollution were used. Thirteen studies were included, originating predominantly from European countries but also the American. They suggested that exercising in an environment with high TRAP exposure increases markers of respiratory and systemic inflammation, as well as, impairs the vascular function and increases artery pressure, when compared with an environment with low-TRAP exposure. In addition, the smaller particles appear to have the most severe health consequences compared with the larger coarse particles and NO2. This study also provides evidence that specific groups of the population have enhanced susceptibility to adverse effects from particulate matter exposure while exercising. There is a need for more studies focused on the relationship between air pollution, physical exercise and health, as large societal benefits can be obtained from healthy environments that can promote outdoor physical exercise.


Assuntos
Poluição do Ar/estatística & dados numéricos , Doenças Cardiovasculares/epidemiologia , Exposição Ambiental/estatística & dados numéricos , Exercício Físico , Doenças Respiratórias/epidemiologia , Emissões de Veículos/análise , Poluentes Atmosféricos , Europa (Continente) , Humanos , Material Particulado
18.
Environ Res ; 179(Pt A): 108740, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31563789

RESUMO

Formaldehyde (FA) is a high-volume production chemical manufactured worldwide to which many people are exposed to both environmentally and occupationally. FA was recently reclassified as a human carcinogen. Several epidemiological studies have revealed an increased risk of cancer development among workers exposed to FA. Although FA genotoxicity was confirmed in a variety of experimental systems, data from human studies are conflicting. The aim of the present study was to evaluate the occupational exposure to FA in a multistage approach relating the exposure with different biomarkers (dose and effect) and individual susceptibility. Air monitoring was performed to estimate the level of exposure to FA during shift work. Eighty-five workers from hospital anatomy-pathology laboratories exposed to FA and 87 controls were tested for cytogenetic alterations in lymphocytes (micronucleus, MN; sister-chromatid exchange, SCE) and T-cell receptor (TCR) mutation assay. The frequency of MN in exfoliated buccal cells, a first contact tissue was also assessed. Percentages of different lymphocyte subpopulations were selected as immunotoxicity biomarkers. The level of formic acid in urine was investigated as a potential biomarker of internal dose. The effects of polymorphic genes of xenobiotic metabolising enzymes and DNA repair enzymes on the endpoints studied were determined. The mean level of FA exposure was 0.38 ±â€¯0.03 ppm. MN (in lymphocytes and buccal cells) and SCE were significantly increased in FA-exposed workers compared to controls. MN frequency positively correlated with FA levels of exposure and duration. Significant alterations in the percentage of T cytotoxic lymphocytes, NK cells and B lymphocytes were found between groups. Polymorphisms in CYP2E1, GSTP1 and FANCA genes were associated with increased genetic damage in FA-exposed subjects. The obtained information may provide new important data to be used by health and safety care programs and by governmental agencies responsible for setting the acceptable levels for occupational exposure to FA.


Assuntos
Poluentes Ocupacionais do Ar/análise , Formaldeído/análise , Mucosa Bucal , Neoplasias/epidemiologia , Exposição Ocupacional/estatística & dados numéricos , Poluentes Ocupacionais do Ar/toxicidade , Biomarcadores/metabolismo , Dano ao DNA , Formaldeído/toxicidade , Humanos , Linfócitos , Testes para Micronúcleos
19.
Pituitary ; 22(2): 124-128, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30684167

RESUMO

PURPOSE: Guidelines on pituitary incidentalomas evaluation and management are limited to adults since there are no data on this matter in the paediatric population. We aim to analyse the morphologic characteristics, hormonal profile and follow-up of these lesions in children. METHODS: We have searched for pituitary incidentalomas in the neuroimaging reports and electronic medical records of the Paediatric Endocrinology Clinic of our centre. Patients with 18 years-old or less were included. RESULTS: Forty-one incidentalomas were identified, 25 of them (62.4%) in females. The mean age at diagnosis was 12.0 ± 4.96 years-old. Headaches were the main reason that led to image acquisition (51.2%) and MRI was the imaging method that detected the majority of the incidentalomas (70.7%). The most prevalent lesion was pituitary hypertrophy (29.3%), which was mainly diagnosed in female adolescents (91.7%), followed by arachnoid cysts (17.1%), pituitary adenomas (14.6%) and Rathke's cleft cysts (12.2%). Most patients (90.2%) did not present clinical or laboratorial findings of hypopituitarism or hormonal hypersecretion. Four patients presented endocrine dysfunction: three had growth hormone deficiency and one had a central precocious puberty. Twenty-three patients (56.1%) underwent imagiological revaluation during a median follow-up time of 24.6 months (interquartile range 5.07). None of them presented dimensional progression. CONCLUSIONS: To the best of our knowledge, this is the first series of pituitary incidentalomas in pediatric age. Comparing our series with those conducted in adults, we have observed a higher preponderance of pituitary hypertrophy over adenomas, a lower prevalence of hormonal hyper/hyposecretion and lower risk of dimensional progression during follow-up.


Assuntos
Neuroimagem/métodos , Hipófise/diagnóstico por imagem , Neoplasias Hipofisárias/diagnóstico por imagem , Adolescente , Criança , Feminino , Humanos , Masculino , Pediatria/métodos , Estudos Retrospectivos
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