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1.
Int J Mol Sci ; 24(12)2023 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-37373136

RESUMO

Exposure to chemical substances has always been a matter of concern for the scientific community. During the last few years, researchers have been focusing on studying the effects resulting from combined exposure to different substances. In this study, we aimed to determine the DNA damage caused after chronic and combined exposure to substances characterized as endocrine disruptors using comet and micronuclei assays, specifically glyphosate (pure and commercial form), bisphenol A, parabens (methyl-, propyl- and butylparaben), triclosan and bis (2-ethylhexyl) phthalate. The highest mean tail intensity was observed in the group exposed to a high-dose (10 × ADI) mixture of substances (Group 3), with a mean value of 11.97 (11.26-13.90), while statistically significant differences were noticed between the groups exposed to low-dose (1 × ADI) (Group 2) and high-dose (10 × ADI) (Group 3) mixtures of substances (p = 0.003), and between Group 3 and both groups exposed to high doses (10 × ADI) of the pure and commercial forms of glyphosate (Groups 4 (p = 0.014) and 5 (p = 0.007)). The micronuclei assay results were moderately correlated with the exposure period. Group 5 was the most impacted exposure group at all sampling times, with mean MN counts ranging between 28.75 ± 1.71 and 60.75 ± 1.71, followed by Group 3 (18.25 ± 1.50-45.75 ± 1.71), showing that commercial forms of glyphosate additives as well as mixtures of endocrine disruptors can enhance MN formation. All exposure groups showed statistically significant differences in micronuclei counts with an increasing time trend.


Assuntos
Disruptores Endócrinos , Triclosan , Disruptores Endócrinos/toxicidade , Parabenos , Dano ao DNA
2.
Arch Toxicol ; 97(5): 1285-1298, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36892595

RESUMO

The current approach for the risk assessment of chemicals does not account for the complex human real-life exposure scenarios. Exposure to chemical mixtures in everyday life has raised scientific, regulatory, and societal concerns in recent years. Several studies aiming to identify the safety limits of chemical mixtures determined hazardous levels lower than those of separate chemicals. Following these observations, this study built on the standards set by the real-life risk simulation (RLRS) scenario and investigated the effect of long-term exposure (18 months) to a mixture of 13 chemicals (methomyl, triadimefon, dimethoate, glyphosate, carbaryl, methyl parathion, aspartame, sodium benzoate, EDTA, ethylparaben, butylparaben, bisphenol A and acacia gum) in adult rats. Animals were divided into four dosing groups [0xNOAEL (control), 0.0025xNOAEL (low dose-LD), 0.01xNOAEL (medium dose-MD) and 0.05xNOAEL (high dose-HD) (mg/kg BW/day)]. After 18 months of exposure, all animals were sacrificed, and their organs were harvested, weighed, and pathologically examined. While organ weight tended to be higher in males than in females, when sex and dose were taken into account, lungs and hearts from female rats had significantly greater weight than that of males. This discrepancy was more obvious in the LD group. Histopathology showed that long-term exposure to the chemical mixture selected for this study caused dose-dependent changes in all examined organs. The main organs that contribute to chemical biotransformation and clearance (liver, kidneys, and lungs) consistently presented histopathological changes following exposure to the chemical mixture. In conclusion, exposure to very low doses (below the NOAEL) of the tested mixture for 18 months induced histopathological lesions and cytotoxic effects in a dose and tissue-dependent manner.


Assuntos
Praguicidas , Masculino , Humanos , Ratos , Feminino , Animais , Nível de Efeito Adverso não Observado , Ratos Sprague-Dawley , Praguicidas/toxicidade , Aditivos Alimentares/toxicidade , Tamanho do Órgão
3.
Int J Mol Sci ; 23(20)2022 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-36293301

RESUMO

An amphiphilic copolymer of N-vinyl-2-pyrrolidone and acrylic acid-namely, p(VP-AA)-OD6000 (p(VP-AA))-was synthesized to prepare p(VP-AA) nanoparticles (NPs). Furthermore, the copolymer was linked with CFSE, and the so-prepared nanoparticles were loaded with the DiI dye to form D nanoparticles (DNPs). In this study, as demonstrated by immunofluorescence microscopy, immunofluorescence, and confocal microscopy, DNPs were readily taken up by human microvascular endothelial cells (HMEC-1) cells in a concentration-dependent manner. Upon uptake, both the CFSE dye (green stain) and the DiI dye (red stain) were localized to the cytoplasm of treated cells. Treatment with p(VP-AA) did not affect the viability of normal and challenged with LPS, HMEC-1 cells at 0.010 mg/mL and induced a dose-dependent decrease of these cells' viability at the higher concentrations of 0.033 and 0.066 mg/mL (p ≤ 0.01; p ≤ 0.001, respectively). Furthermore, we focused on the potential immunological activation of HMEC-1 endothelial cells upon p(VP-AA) NPs treatment by assessing the expression of adhesion molecules (E-Selectin, ICAM-1, and V-CAM). NPs treatments at concentrations utilized (p = NS) did not affect individual adhesion molecules' expression. p(VP-AA) NPs do not activate the endothelium and do not affect its viability at pharmacologically relevant concentrations.


Assuntos
Selectina E , Nanopartículas , Humanos , Molécula 1 de Adesão Intercelular , Células Endoteliais , Lipopolissacarídeos/farmacologia , Polímeros , Endotélio
4.
Front Oncol ; 11: 683605, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34262868

RESUMO

PURPOSE: Due to the current practice on colorectal cancer (CRC) management, chemoresistance is most often recognized at the end of the treatment. Therefore, effective and easy-to-use prognostic biomarkers are needed. EXPERIMENTAL DESIGN: We evaluated the prognostic significance of two novel CRC biomarkers: a) micronuclei frequency (MNf) in 55 metastatic CRC (mCRC) and 21 locally advanced rectal cancer (laRC) patients using cytokinesis block micronucleus assay (CBMN assay) and b) telomerase activity (TA) in 23 mCRC and five laRC patients using TRAP-ELISA. Both biomarkers were evaluated in peripheral blood lymphocytes (PBLs) before, at the middle, and at the end of the therapy (approximately 0, 3, and 6 months) for mCRC patients before, at the end of the therapy, and after surgery for laRC patients. RESULTS: Overall, MNf demonstrated significant prognostic value since a decrease of MNf less than 29% between middle and initial MNf measurements can discriminate between progressive and stable/responsive disease with sensitivity of 36% and specificity of 87.0% while being able to identify responsive disease with sensitivity of 72.7% and specificity of 59.3%. On the other hand, TA presented a significant trend of increase (p = 0.07) in patients with progressive disease at the middle measurement. CONCLUSIONS: The findings of this study suggest that the MN frequency may serve as a promising prognostic biomarker for the monitoring of the treatment response of patients with CRC, while TA should be evaluated in a larger group of patients to further validate its significance.

5.
Toxicol Rep ; 8: 988-993, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34026563

RESUMO

The present work assessed the effect of copper (Cu) on cell dynamics and structure of the microalga Porphyridium purpureum (Rhodophyta, Bangiophycidae). Ultrastructure of the microalga was investigated and fluorescence of chlorophyll a and phycoerythrin, and content of reactive oxygen species (ROS) were estimated by flow cytometry. The number of cells did not show statistically significant differences at concentrations of 50 and 100 µg/L of Cu compared to the control, whereas 150 µg/L of Cu inhibited population growth. The fluorescence of chlorophyll a increased following exposure to Cu 100 µg/L and fluorescence of phycoerythrin enhanced by Cu 150 µg/L. There was no alteration in the above indicators at other concentrations. The content of ROS increased with increasing Cu concentration in a dose-dependent manner. The population size structure was also changed by Cu as the number of cells sized 4-6 µm was increased in the presence of Cu, especially with Cu 150 µg/L. Changes in the topography of thylakoids grew larger with Cu concentration.

6.
Molecules ; 25(22)2020 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-33217959

RESUMO

Curcumin's pharmacological properties and its possible benefits for neurological diseases and dementia have been much debated. In vitro experiments show that curcumin modulates several key physiological pathways of importance for neurology. However, in vivo studies have not always matched expectations. Thus, improved formulations of curcumin are emerging as powerful tools in overcoming the bioavailability and stability limitations of curcumin. New studies in animal models and recent double-blinded, placebo-controlled clinical trials using some of these new formulations are finally beginning to show that curcumin could be used for the treatment of cognitive decline. Ultimately, this work could ease the burden caused by a group of diseases that are becoming a global emergency because of the unprecedented growth in the number of people aged 65 and over worldwide. In this review, we discuss curcumin's main mechanisms of action and also data from in vivo experiments on the effects of curcumin on cognitive decline.


Assuntos
Curcumina/uso terapêutico , Composição de Medicamentos , Doenças do Sistema Nervoso/tratamento farmacológico , Animais , Ensaios Clínicos como Assunto , Cognição/efeitos dos fármacos , Curcumina/farmacologia , Modelos Animais de Doenças , Humanos , Doenças do Sistema Nervoso/sangue
7.
Mol Pharm ; 17(11): 4212-4225, 2020 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-32986447

RESUMO

Nanoparticles (NPs) produced from amphiphilic derivatives of poly-N-vinylpyrrolidone (Amph-PVP), composed of various molecular weight polymeric hydrophilic fragments linked into hydrophobic n-alkyl chains of varying lengths, were previously shown to exert excellent biocompatibility. Although routes of administration can be different, finally, most nanosystems enter the blood circulation or lymphatic vessels, and by this, they establish direct contact with endothelial cells. In this study, Amph-PVP NPs and fluorescently labeled Amph-PVP-based NPs, namely "PVP" NPs (Amph-PVP-NPs (6000 Da) unloaded) and "F"-NPs (Amph-PVP-NPs (6000 Da) loaded with fluorescent FITC), were synthesized to study Amph-PVP NPs interactions with HMEC-1 endothelial cells. PVP NPs were readily uptaken by HMEC-1 cells in a concentration-dependent manner, as demonstrated by immunofluorescence imaging. Upon uptake, the FITC dye was localized to the perinuclear region and cytoplasm of treated cells. The generation of lipopolysaccharide (LPS)-induced activated endothelium model revealed an increased uptake of PVPNPs, as shown by confocal microscopy. Both unloaded PVP NPs and F-NPs did not affect EC viability in the 0.01 to 0.066 mg/mL range. Furthermore, we focused on the potential immunological activation of HMEC-1 endothelial cells upon PVPNPs treatment by assessing the expression of their E-Selectin, ICAM-1, and VCAM-1 adhesion receptors. None of the adhesion molecules were affected by NP treatments of both activated by LPS and nonactivated HMEC-1 cells, at the utilized concentrations (p = NS). In this study, PVP (6000 Da) NPs were used to encapsulate indomethacin, a widely used anti-inflammatory drug. The synthesized drug carrier complex did not affect HMEC-1 cell growth and expression of E-selectin, ICAM-1, and VCAM-1 adhesion receptors. In summary, PVP-based NPs are safe for use on both basal and activated endothelium, which more accurately mimics pathological conditions. Amph-PVP NPs are a promising drug delivery system.


Assuntos
Anti-Inflamatórios/administração & dosagem , Materiais Biocompatíveis/química , Portadores de Fármacos/química , Células Endoteliais/efeitos dos fármacos , Indometacina/administração & dosagem , Nanopartículas/química , Polímeros/química , Pirrolidinonas/química , Anti-Inflamatórios/metabolismo , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Células Endoteliais/metabolismo , Fluoresceína-5-Isotiocianato/administração & dosagem , Corantes Fluorescentes/administração & dosagem , Corantes Fluorescentes/metabolismo , Humanos , Interações Hidrofóbicas e Hidrofílicas , Indometacina/metabolismo , Peso Molecular , Tamanho da Partícula
8.
Toxicol Rep ; 7: 1090-1094, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32953461

RESUMO

Genotoxicity of the mixture of generic pesticides imidacloprid + imazalil + tebuconazole in a ratio of 14.0/1.7/1.0 by weight was assessed using Ames test (Salmonella typhimurium) and micronucleus test in vivo on mammalian bone marrow erythrocytes (CD-1 mice) supporting the data creation for the Real Life Risk Simulation (RLRS) approach. This pesticides' combination is used in the commercial formulation for seed treatment in advance of or immediately before sowing. Tested pesticides' technical grade active ingredients (TGAIs) showed no evidence of genotoxicity upon separate treatments. In combination, the three pesticides demonstrated negative results in the Ames test but induced a statistically significant, dose-depended increase in MN-PCEs in mice bone marrow at doses lower than those used separately. The observed effect may be mediated by the synergistic action of the tested TGAIs, their metabolites or impurities.

9.
Toxicol Rep ; 7: 947-954, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32793424

RESUMO

Carbon nanofibers (CNFs) are widely used in consumer products today. In this study, we assessed the effects of CNFs on the digestive system of three freshwater invertebrate species (Gammaridae, Ephemerellidae, and Chironomidae). The aquatic insects Diamesa sp., Drunella cryptomeria, and Gammarus suifunensis were incubated with the CNFs at the concentration of 100 mg/L during the 7-days period. Histological examination of the whole specimens and the longitudinal sections revealed no toxic effects of CNFs. However, a noticeable change in the structure of the CNFs accumulated in the intestines of the aquatic insects was found by Raman spectroscopy. The registered decrease in the relative proportion of amorphous carbon included in the CNF sample was found in the intestines of Diamesa sp. and D. cryptomeria. The registered effect can indicate a biodegradation of amorphous carbon in the digestive tract of these two insect species. In contrast, the decrease of highly structured carbons and the decrease of G-bonds intensity were registered in the digestive tract of G. suifunensis. This observation demonstrates the partial biodegradation of CNFs in the digestive tract of G. suifunensis.

10.
Food Chem Toxicol ; 140: 111262, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32198030

RESUMO

Pesticides are widely used in agriculture and their proven high toxicity makes the need of monitoring their presence in food imperative. A multi residue method is applied in apples samples (81) collected from the Greek market for the monitoring of 40 analytes. Pesticides levels were evaluated by gas and liquid chromatography-mass spectrometry using a QuEChERs protocol. Risk for consumers was assessed by a newly developed methodology, employing the source related Hazard Quotient (HQs) and the adversity specific Hazard Index (HIA). The 84% of the apple's samples were positive for at least one pesticide, 21% for one pesticide, 55.6% for two to four pesticide residues and 7.4% for more than 4 pesticide residues. The most frequently detected compound was carbendazim (45.7%) followed by chlorpyrifos (44.4.0%). The mean detected concentration levels varied from 0.169 ppm (fluopyram) to 0.005 ppm (triazophos). 19 of the 40 investigated pesticides were not detected in any apple sample. For all individual pesticides, the source related Hazard Quotient (HQs) was <1 indicating no risk. HIA, resulting from the sum of all HQs was found HIA < 1 in nine out of ten toxicity groups, except to the neurotoxicity group, which presented HIA 2.258, indicating moderate risk.


Assuntos
Contaminação de Alimentos/análise , Fungicidas Industriais/análise , Inseticidas/análise , Malus/química , Resíduos de Praguicidas/análise , Cromatografia Líquida/métodos , Cromatografia Gasosa-Espectrometria de Massas/métodos , Grécia , Medição de Risco , Espectrometria de Massas em Tandem/métodos
11.
Exp Ther Med ; 19(3): 1626-1632, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32104213

RESUMO

Osteoarthritis (OA) and osteoporosis (OP) are associated skeletal pathologies and have as a distinct feature the abnormal reconstruction of the subchondral bone. OA and OP have been characterized as age-related diseases and have been associated with telomere shortening and altered telomerase activity (TA). This review discusses the role of telomeres and telomerase in OA and OP pathologies and focuses on the usability of telomere length (TL) and the rate of telomere shortening as potential disease biomarkers. A number of studies have demonstrated that telomere shortening may contribute to OA and OP as an epigenetic factor. Therefore, it has been claimed that the measurement of TL of chondrocytes and/or peripheral blood cells may be an appropriate marker for the evaluation of the progression of these diseases. However, there is a need to be perform further studies with larger cohorts, with the aim of obtaining objective results and a better understanding of the association between TL, inflammation and aging, in order to provide further insight into the pathophysiology of degenerative joint diseases.

13.
Toxicol Lett ; 316: 154-170, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31521832

RESUMO

The present study investigates the genotoxic and cytotoxic effects of long term exposure to low doses of a mixture consisting of methomyl, triadimefon, dimethoate, glyphosate, carbaryl, methyl parathion, aspartame, sodium benzoate, EDTA, ethylparaben, buthylparaben, bisphenol A and acacia gum in rats. Four groups of ten Sprangue Dawley rats (5 males and 5 females per group) were exposed for 18 months to the mixture in doses of 0xNOAEL, 0.0025xNOAEL, 0.01xNOAEL and 0.05xNOAEL (mg/kg bw/day). After 18 months of exposure, the rats were sacrificed and their organs were harvested. Micronuclei frequency was evaluated in bone marrow erythrocytes whereas the organs were cytopathologically examined by the touch preparation technique. The exposure to the mixture caused a genotoxic effect identified only in females. Cytopathological examination showed specific alterations of tissue organization in a tissue-type dependent manner. The observed effects were dose-dependent and correlated to various tissue parameters. Specifically, testes samples revealed degenerative and cellularity disorders, liver hepatocytes exhibited decreased glycogen deposition whereas degenerative changes were present in gastric cells. Lung tissue presented increased inflammatory cells infiltration and alveolar macrophages with enhanced phagocytic activity, whereas brain tissue exhibited changes in glial and astrocyte cells' numbers. In conclusion, exposure to very low doses of the tested mixture for 18 months induces genotoxic effects as well as monotonic cytotoxic effects in a tissue-dependent manner.


Assuntos
Metabolismo Energético/efeitos dos fármacos , Micronúcleos com Defeito Cromossômico/induzido quimicamente , Testes para Micronúcleos , Testes de Toxicidade Crônica , Animais , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Feminino , Masculino , Nível de Efeito Adverso não Observado , Ratos Sprague-Dawley , Medição de Risco , Fatores Sexuais , Fatores de Tempo
14.
Toxicol Rep ; 6: 395-400, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31080747

RESUMO

Identification of novel biomarkers of contrast-induced nephropathy (CIN) that may more accurately detect renal function changes; reflect kidney damage; assist monitoring; and elucidate pathophysiology attract considerable scientific attention nowadays. To evaluate novel biomarkers of nephrotoxicity in blood/tissue samples of a CIN model, 10 New Zealand white rabbits were divided into group 1 (n = 5; iopromide) and group 2 (n = 5; control). Blood was drawn at 0 h (immediately), 24 h and 48 h after contrast medium (CM) administration. Animals were euthanized at 48 h and kidneys were removed. Serum creatinine (sCr)/symmetric-asymmetric dimethylarginine (SDMA-ADMA) levels were measured. CM genotoxic/cytotoxic effect was investigated 48 h post-CM exposure using micronucleus assay in lymphocytes. Cytological examination was conducted using touch preparation technique (TPT). All animals in group 1 developed CIN: mean sCr levels increased by 68.2% within 48 h. Significant SDMA-ADMA level elevation was observed at 0 h and 24 h with insignificant drop at 48 h in group 1, remaining normal in group 2 at all time-points. Significant increase in bi-nucleated cells with micronuclei and micronuclei frequency was detected in group 1. Cytokinesis block proliferation index was reduced insignificantly in group 1. TPT revealed degenerative lesions/inflammation, cell degeneration, abnormal uterine tubular casts and rubella in kidneys of all animals in group 1. Group 2 presented normal cells.

15.
Toxicol Lett ; 310: 70-91, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30999039

RESUMO

The aim of the current study was to evaluate the effects of a mixture of thirteen common chemicals on rats, after a one-year exposure to doses around the acceptable daily intake (ADIs), using blood and urinary tests. The influence of low doses of the mixture on weight gain, water consumption, feed consumption and feed efficiency, biochemistry parameters, haematological parameters, blood lymphocytes subsets, serum inflammation profile and urine parameters was evaluated. Our mixture caused a moderate monotonic increase of the males' appetite and a non-monotonic increase of anabolism and a monotonic increase of appetite for the females. Regarding biochemical parameters, the exposure to the test mixture caused non-monotonic increases of AST and ALT, a decrease of PChE in males and plausibly a monotonic biliary obstruction in both sexes. Monocytes significantly increased in low dose groups of both sexes. A significant decrease of all the lymphocytes subclasses and an increased expression of TNF-α protein associated with an increased expression of IFN-γ protein observed in various groups. It became apparent that after twelve months of exposure very low doses of the tested mixture had both non-monotonic and monotonic harmful effects on different levels on rats.


Assuntos
Misturas Complexas/toxicidade , Aditivos Alimentares/toxicidade , Praguicidas/toxicidade , Testes de Toxicidade Crônica , Animais , Regulação do Apetite/efeitos dos fármacos , Biomarcadores/sangue , Biomarcadores/urina , Colestase/induzido quimicamente , Citocinas/sangue , Citocinas/urina , Ingestão de Líquidos/efeitos dos fármacos , Ingestão de Alimentos/efeitos dos fármacos , Feminino , Hormese , Mediadores da Inflamação/sangue , Mediadores da Inflamação/urina , Linfócitos/efeitos dos fármacos , Linfócitos/metabolismo , Masculino , Monócitos/efeitos dos fármacos , Monócitos/metabolismo , Ratos Sprague-Dawley , Medição de Risco , Fatores de Tempo , Aumento de Peso/efeitos dos fármacos
16.
Oncol Lett ; 17(3): 2703-2712, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30854044

RESUMO

Colorectal cancer (CRC) is the third most diagnosed type of cancer affecting males, and the second most diagnosed type of cancer affecting females, and one of the leading causes of cancer-related mortality globally. The estimation of the micronuclei (MN) frequency in peripheral blood lymphocytes (PBLs) from patients with CRC is proposed as a prognostic/predictive easy-to-use biomarker. In this study, we aimed to investigate the effects of systemic treatment on the MN frequency in PBLs from patients with CRC in order to determine the effectiveness of the MN frequency as a biomarker. For this purpose, from 2016 to 2018, we quantified the MN frequency as a prognostic/predictive biomarker in serial samples from 25 patients with metastatic CRC (mCRC) using cytokinesis block micronucleus assay (CBMN assay). The MN frequency in the PBLs of the patients was evaluated before, during the middle and at the end of the therapy (approximately 0, 3 and 6 months). The results revealed a common pattern regarding the fluctuation in the MN frequency. Statistical analysis confirmed that when the disease response was estimated with radiological criteria, a good response was depicted at the MN frequency and vice versa. Consequently, the findings of this study suggest that the MN frequency may serve as a promising prognostic/predictive biomarker for the monitoring of the treatment response of patients with CRC.

17.
Toxicol Rep ; 6: 105-110, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30622904

RESUMO

Effects of technical materials of pesticide active ingredients, belonging to various chemical classes, on erythropoiesis in mouse bone marrow were studied as part of the research on the pesticide mutagenic activity in micronucleus test. The purpose of the present study was to estimate the toxic action of the test substances on the target organ and the validity of the results of the micronucleus assay under conditions of erythropoiesis suppression. It was demonstrated that intragastrically administrated triazole pesticides reached bone marrow (target organ where micronucleus induction was assessed) and exerted an inhibitory effect on erythropoiesis. The effects of triazole pesticides were enhanced in the following order: difenoconazole ≤ tebuconazole < cyproconazole < flutriafol. Furthermore, an association between structural features of molecules and specific target organ activity of the test pesticides was observed. Based on the data on the general toxicity and the results of the evaluation of the effects on erythropoiesis, the maximum tolerated doses (MTDs) of 79 different technical materials of pesticides for CD-1 mice were determined.

18.
Inhal Toxicol ; 30(9-10): 361-369, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30369275

RESUMO

BACKGROUND: The aim of the present study was to identify the composition and reported chemical health hazards of the most common electronic cigarette liquids (e-liquids) in nine European Union (EU) Member States (MS) prior to adoption of the Tobacco Product Directive (TPD). MATERIALS AND METHODS: Within the Horizon2020, EUREST-PLUS study, 122 of the most commonly sold e-liquids in 9 EU MS were randomly selected and purchased. A quantitative and qualitative chemical analysis was performed using a previously validated based gas chromatography-mass spectrometry and liquid chromatography-mass spectrometry method. The most commonly detected compounds were then divided according to the Danger Globally Harmonized System of Classification and Labelling of Chemicals (GHS) and Warning GHS codes. RESULTS: Within our qualitative analysis, 171 different compounds were detected. Discrepancies in measured versus reported nicotine concentration were identified. Forty-one (85.4%) of the most commonly detected compounds were registered with Warning GHS codes, 11 with Danger GHS codes and 9 with both codes. Of the total number of the detected compounds, 293 were attributable to fruits flavor, followed by tobacco flavor (204), nonalcoholic drinks (n = 64), desserts-sweets (n = 50), menthol - mint (n = 42) and alcohol (n = 39). Menthol which is classified as a strong irritant to skin and eye was the most frequently detected compound. CONCLUSION: A large plethora of compounds with varying warning codes was identified in e-cigarette samples. The systematic monitoring and chemical evaluation of e-liquids are warranted, so as to ensure consumer protection.


Assuntos
Sistemas Eletrônicos de Liberação de Nicotina , Aromatizantes/análise , Nicotina/análise , Cromatografia Líquida , Europa (Continente) , Cromatografia Gasosa-Espectrometria de Massas
19.
Nanomedicine (Lond) ; 13(13): 1595-1606, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-30028222

RESUMO

AIM: The present study was designed to evaluate the effects of irinotecan hydrochloride (IRI)- or metformin hydrochloride (MET)-loaded poly-lactic-co-glycolic acid (PLGA) nanoparticles (NPs) for the treatment of glioblastoma multiforme using in vitro neuron and U-87 MG glioblastoma cell cultures and in vivo animal model. METHODS: The cytotoxic and neurotoxic effects of pure drugs, blank NPs and MET- and IRI-loaded PLGA NPs were investigated in vitro (using methylthiazolyldiphenyl-tetrazolium bromide assay) and in vivo (using Cavalieri's principle for estimation of cancer volume). RESULTS: 1 and 2 mM doses of MET and MET-loaded PLGA NPs, respectively, significantly reduced the volume of extracted cancer. CONCLUSION: Consequently, MET- and IRI-loaded PLGA NPs may be a promising approach for the treatment of glioblastoma multiforme.


Assuntos
Glioblastoma/tratamento farmacológico , Irinotecano/administração & dosagem , Metformina/administração & dosagem , Nanopartículas/administração & dosagem , Neoplasias Experimentais/tratamento farmacológico , Animais , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Portadores de Fármacos/administração & dosagem , Portadores de Fármacos/química , Glioblastoma/patologia , Humanos , Irinotecano/química , Metformina/química , Microscopia Eletrônica de Transmissão , Nanopartículas/química , Neoplasias Experimentais/patologia , Neurônios/efeitos dos fármacos , Neurônios/patologia , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/administração & dosagem , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química , Ratos
20.
Int J Mol Med ; 42(1): 405-413, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29717770

RESUMO

Anabolic agents are doping substances which are commonly used in sports. Stanozolol, a 17α­alkylated derivative of testosterone, has a widespread use among athletes and bodybuilders. Several medical and behavioral adverse effects are associated with anabolic androgenic steroids (AAS) abuse, while the liver remains the most well recognized target organ. In the present study, the hepatic effects of stanozolol administration in rats at high doses resembling those used for doping purposes were investigated, in the presence or absence of exercise. Stanozolol and its metabolites, 16­ß­hydroxystanozolol and 3'­hydroxystanozolol, were detected in rat livers using liquid chromatography­mass spectrometry (LC­MS). Telomerase activity, which is involved in cellular aging and tumorigenesis, was detected by examining telomerase reverse transcriptase (TERT) and phosphatase and tensin homolog (PTEN) expression levels in the livers of stanozolol­treated rats. Stanozolol induced telomerase activity at the molecular level in the liver tissue of rats and exercise reversed this induction, reflecting possible premature liver tissue aging. PTEN gene expression in the rat livers was practically unaffected either by exercise or by stanozolol administration.


Assuntos
Envelhecimento/fisiologia , Fígado/fisiologia , Condicionamento Físico Animal , Estanozolol/administração & dosagem , Estanozolol/farmacologia , Telomerase/metabolismo , Animais , Regulação da Expressão Gênica/efeitos dos fármacos , Imuno-Histoquímica , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Metaboloma/efeitos dos fármacos , PTEN Fosfo-Hidrolase/genética , PTEN Fosfo-Hidrolase/metabolismo , Ratos Sprague-Dawley , Estanozolol/análogos & derivados , Telômero/metabolismo
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