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1.
Am J Physiol Cell Physiol ; 323(6): C1740-C1756, 2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-36280393

RESUMO

Biglycan is a class I secreted small leucine-rich proteoglycan (SLRP), which regulates signaling pathways connected to bone pathologies. Autophagy is a vital catabolic process with a dual role in cancer progression. Here, we show that biglycan inhibits autophagy in two osteosarcoma cell lines (P ≤ 0.001), while rapamycin-induced autophagy decreases biglycan expression in MG63 osteosarcoma cells and abrogates the biglycan-induced cell growth increase (P ≤ 0.001). Rapamycin also inhibits ß-catenin translocation to the nucleus, inhibiting the Wnt pathway (P ≤ 0.001) and reducing biglycan's colocalization with the Wnt coreceptor LRP6 (P ≤ 0.05). Furthermore, biglycan exhibits protective effects against the chemotherapeutic drug doxorubicin in MG63 OS cells through an autophagy-dependent manner (P ≤ 0.05). Cotreatment of these cells with rapamycin and doxorubicin enhances cells response to doxorubicin by decreasing biglycan (P ≤ 0.001) and ß-catenin (P ≤ 0.05) expression. Biglycan deficiency leads to increased caspase-3 activation (P ≤ 0.05), suggesting increased apoptosis of biglycan-deficient cells treated with doxorubicin. Computational models of LRP6 and biglycan complexes suggest that biglycan changes the receptor's ability to interact with other signaling molecules by affecting the interdomain bending angles in the receptor structure. Biglycan binding to LRP6 activates the Wnt pathway and ß-catenin nuclear translocation by disrupting ß-catenin degradation complex (P ≤ 0.01 and P ≤ 0.05). Interestingly, this mechanism is not followed in moderately differentiated, biglycan-nonexpressing U-2OS OS cells. To sum up, biglycan exhibits protective effects against the doxorubicin in MG63 OS cells by activating the Wnt signaling pathway and inhibiting autophagy.


Assuntos
Neoplasias Ósseas , Osteossarcoma , Humanos , Via de Sinalização Wnt , beta Catenina/metabolismo , Sirolimo/farmacologia , Linhagem Celular Tumoral , Osteossarcoma/tratamento farmacológico , Osteossarcoma/metabolismo , Proliferação de Células , Autofagia , Doxorrubicina/farmacologia , Neoplasias Ósseas/metabolismo
2.
Tob Control ; 29(5): 531-536, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-31519795

RESUMO

OBJECTIVE: To evaluate electronic cigarette (e-cigarette) product compliance with European regulations (Tobacco Products Directive (TPD), Implementing Decisions), with a focus on labelling/packaging practices and technical design/safety features. METHODS: Before the implementation of the TPD, in early 2016, we randomly selected e-cigarette refill liquids from the five top-selling companies in France, Poland, Germany, Netherlands, UK, Spain, Romania, Hungary and Greece. Identical products were purchased after the implementation of the TPD (early 2018) and assessment of compliance was performed on self-matched samples (n=107) using a prospective cohort design. Compliance with the Classification, Labelling and Packaging (CLP) regulations was also evaluated. RESULTS: Following the implementation of the TPD, improvements were noted with regards to the existence of text-only warnings (32.7% pre vs 86.0% post, p<0.001), child-resistant fastenings (93.3% pre vs 100.0% post, p=0.016), tamper-proof vials (58.9% pre vs 86.9%, post p<0.001) and maximum refill volume ≤10 mL in vials (86.9% pre vs 94.4% post, p=0.008). Lower compliance was noted with regards to the inclusion of a leaflet (26.2% pre vs 53.3% post, p<0.001), refilling instructions (28.0% pre vs 51.4% post, p<0.001) and health warnings on the box, vial or leaflet (32.7% pre vs 86.0%, p<0.001). Overall, 86.0% of products had a warning label in the post-TPD phase in comparison to 32.7% of products before the implementation of the TPD (p<0.001). Compliance with the CLP regulations, also increased in the post TPD follow-up phase. CONCLUSIONS: This is the first study to evaluate the level of implementation of the e-cigarette regulations in nine EU member states. Our results indicate that refill liquids had substantial but not full compliance in most of the characteristics evaluated. Further effort is needed to ensure complete compliance.


Assuntos
Comportamento do Consumidor , Sistemas Eletrônicos de Liberação de Nicotina , Regulamentação Governamental , Nicotina , Rotulagem de Produtos , União Europeia , Humanos
3.
Environ Res ; 179(Pt A): 108785, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31606615

RESUMO

Air pollution caused by vehicle emissions remains a serious environmental threat in urban areas. Sedimentation of atmospheric aerosols, surface wash, drainage water, and urbane wastewater can bring vehicle particle emissions into the aquatic environment. However, the level of toxicity and mode of toxic action for this kind of particles are not fully understood. Here we explored the aquatic toxic effects of particulate matter emitted from different types of vehicles on marine microalgae Porphyridium purpureum and Heterosigma akashiwo. We used flow cytometry to evaluate growth rate inhibition, changes in the level of esterase activity, changes in membrane potential and size changes of microalgae cells under the influence of particulate matter emitted by motorcycles, cars and specialized vehicles with different types of engines and powered by different types of fuel. Both microalgae species were highly influenced by the particles emitted by diesel-powered vehicles. These particle samples had the highest impact on survival, esterase activity, and membrane potential of microalgae and caused the most significant increase in microalgae cell size compared to the particles produced by gasoline-powered vehicles. The results of the algae-bioassay strongly correlate with the data of laser granulometry analyses, which indicate that the most toxic samples had a significantly higher percentage of particles in the size range less than 1 µm. Visual observation with an optical microscope showed intensive agglomeration of the particles emitted by diesel-powered vehicles with microalgae cells. Moreover, within the scope of this research, we did not observe the direct influence of metal content in the particles to the level of their aquatic toxicity, and we can conclude that physical damage is the most probable mechanism of toxicity for vehicle emitted particles.


Assuntos
Poluentes Atmosféricos/toxicidade , Microalgas/efeitos dos fármacos , Material Particulado/toxicidade , Emissões de Veículos/toxicidade , Monitoramento Ambiental , Gasolina , Veículos Automotores , Tamanho da Partícula
4.
Arch Toxicol ; 92(10): 3031-3050, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30097700

RESUMO

Chemical allergens are small molecules able to form a sensitizing complex once they bound to proteins. One of the most frequent manifestations of chemical allergy is contact hypersensitivity, which can have serious impact on quality of life. Allergic contact dermatitis is a predominantly CD8 + T cell-mediated immune disease, resulting in erythema and eczema. Chemical allergy is of considerable importance to the toxicologist, who has the responsibility of identifying and characterizing the allergenic potential of chemicals, and estimating the risk they pose to human health. This review aimed at exploring the phenomena of chemical-induced contact allergy starting from a mechanistic understanding, immunoregulatory mechanisms, passing through the potency of contract allergen until the hazard identification, pointing out the in vitro models for assessing contact allergen-induced cell activation and the risk prevention.


Assuntos
Alérgenos/toxicidade , Dermatite Alérgica de Contato/etiologia , Dermatite Alérgica de Contato/prevenção & controle , Testes de Toxicidade/métodos , Alérgenos/imunologia , Animais , Matriz Extracelular/imunologia , Matriz Extracelular/metabolismo , Humanos , Tolerância Imunológica , Nanopartículas/toxicidade , Pele/efeitos dos fármacos , Receptores Toll-Like/imunologia , Testes de Toxicidade/normas
5.
J Appl Toxicol ; 38(8): 1144-1152, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29722443

RESUMO

Bisphenol A (BPA), triclosan (TCS) and perfluorooctanoic acid (PFOA) are endocrine disruptors linked with negative health effects such as developmental, reproductive and cardiovascular toxicity. The aim of this study was to determine simultaneously the concentration of BPA, TCS and PFOA in hair from children and adults and examine possible associations between biomonitoring data and age, gender, dietary habits and body mass index. Methanolic extraction was applied and the compounds were determined by liquid chromatography-mass spectrometry. Low levels of exposure to PFOA were detected for children and adults at concentrations below limit of quantification. The mean concentration of BPA in children and adults was 20.6 and 16.6 pg mg-1 , while for TCS 275.2 and 687.0 pg mg-1 , respectively. Children were highly exposed to BPA relative to adults (P = .011) although adults had greater exposure to TCS (P = .003). Hair from girls had a greater burden of BPA (P = .06) compared to boys. Moreover, higher TCS levels were depicted for females in both examined groups (children P = .200 and adults P = .213) compared to males, but no statistical differences were observed. Significant differences were also observed between age groups (P = .0007) for TCS. No correlations were found between BPA or TCS levels and body mass index or dietary habits for both children and adults. Children have a greater exposure to BPA compared to adults, whereas exposure of adults to TCS seems to be higher than that in children and elderly people. Exposure to BPA occurs mainly via ingestion whereas exposure to TCS mainly via dermal absorption.


Assuntos
Compostos Benzidrílicos/análise , Caprilatos/análise , Disruptores Endócrinos/análise , Monitoramento Ambiental/métodos , Fluorocarbonos/análise , Cabelo/química , Fenóis/análise , Triclosan/análise , Adulto , Fatores Etários , Índice de Massa Corporal , Criança , Comportamento Alimentar , Grécia , Humanos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Fatores Sexuais
6.
Int J Mol Sci ; 19(5)2018 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-29772829

RESUMO

Humans are exposed to a significant number of chemicals that are suspected to produce disturbances in hormone homeostasis. Hence, in recent decades, there has been a growing interest in endocrine disruptive chemicals. One of the alleged thyroid disrupting substances is cadmium (Cd), a ubiquitous toxic metal shown to act as a thyroid disruptor and carcinogen in both animals and humans. Multiple PubMed searches with core keywords were performed to identify and evaluate appropriate studies which revealed literature suggesting evidence for the link between exposure to Cd and histological and metabolic changes in the thyroid gland. Furthermore, Cd influence on thyroid homeostasis at the peripheral level has also been hypothesized. Both in vivo and in vitro studies revealed that a Cd exposure at environmentally relevant concentrations results in biphasic Cd dose-thyroid response relationships. Development of thyroid tumors following exposure to Cd has been studied mainly using in vitro methodologies. In the thyroid, Cd has been shown to activate or stimulate the activity of various factors, leading to increased cell proliferation and a reduction in normal apoptotic activity. Evidence establishing the association between Cd and thyroid disruption remains ambiguous, with further studies needed to elucidate the issue and improve our understanding of Cd-mediated effects on the thyroid gland.


Assuntos
Cádmio/farmacologia , Disruptores Endócrinos/farmacologia , Glândula Tireoide/efeitos dos fármacos , Glândula Tireoide/metabolismo , Animais , Cádmio/toxicidade , Intoxicação por Cádmio , Disruptores Endócrinos/toxicidade , Exposição Ambiental/efeitos adversos , Humanos , Doenças da Glândula Tireoide/etiologia , Doenças da Glândula Tireoide/metabolismo , Testes de Função Tireóidea , Neoplasias da Glândula Tireoide/etiologia , Neoplasias da Glândula Tireoide/metabolismo , Neoplasias da Glândula Tireoide/patologia
7.
IUBMB Life ; 69(11): 824-833, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28940845

RESUMO

Syndecan 2 (SDC2) belongs to a four-member family of evolutionary conserved small type I transmembrane proteoglycans consisting of a protein core to which glycosaminoglycan chains are covalently attached. SDC2 is a cell surface heparan sulfate proteoglycan, which is increasingly drawing attention for its distinct characteristics and its participation in numerous cell functions, including those related to carcinogenesis. Increasing evidence suggests that the role of SDC2 in cancer pathogenesis is dependent on cancer tissue origin rendering its use as a biomarker/therapeutic target feasible. This mini review discusses the mechanisms, through which SDC2, in a distinct manner, modulates complex signalling networks to affect cancer progression. © 2017 IUBMB Life, 69(11):824-833, 2017.


Assuntos
Neoplasias da Mama/genética , Neoplasias do Colo/genética , Fibrossarcoma/genética , Regulação Neoplásica da Expressão Gênica , Osteossarcoma/genética , Neoplasias Pancreáticas/genética , Sindecana-2/genética , Citoesqueleto de Actina/metabolismo , Citoesqueleto de Actina/patologia , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Membrana Celular/metabolismo , Membrana Celular/patologia , Neoplasias do Colo/metabolismo , Neoplasias do Colo/patologia , Progressão da Doença , Feminino , Fibrossarcoma/metabolismo , Fibrossarcoma/patologia , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/genética , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Especificidade de Órgãos , Osteossarcoma/metabolismo , Osteossarcoma/patologia , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/patologia , Domínios Proteicos , Transdução de Sinais , Sindecana-2/metabolismo
8.
Environ Res ; 157: 173-181, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28570961

RESUMO

Cadmium (Cd) has proved to be associated with numerous toxic effects in aquatic organisms via waterborne exposure. With a view to investigate Cd toxicity along a broad spectrum of exposures reaching from environmental to toxic, we employed adult zebrafish (Danio rerio) for an in vivo study. A number of 10 fish per tank were placed in 40L tanks and were exposed for 30 days to 0.0, 5.0, 25, 50, 75, 100 and 1000µgCd per liter. There were 2 tanks for each Cd exposure (duplicate experiment). Mortality was recorded daily, dead fish were collected and tissue samples were obtained for histologic observation, whereas remaining tissues were stored for Cd burden determination. Surviving fish were collected at the end of the experiment. Median overall survival (OS) in days was found to be 9.0, 11.0, 8.0 and 7.0 for 25µg/L, 50µg/L, 75µg/L and 100µg/L respectively, with all of them showing mortality greater than 50%. Remarkably, fish exposed to the highest Cd concentration (1000µg/L) survived the longest exhibiting a mean OS of 29.2 days. Cd determination in fish tissue was conducted with an in house ICP-MS method and levels ranged from 3.1 to 29.1ng/mg. Log Cd tissue levels were significantly correlated with the log Cd exposure levels (r = 0.535, p < 0.001). The highest Cd burden was determined for fish exposed to 1000µgCd /L (mean = 12.2ng/mg). Histopathology supported these results. Our findings disclose a deviation in toxic responses through the range of Cd concentrations, leading to nonlinear responses. These differentiated responses, could be linked to hormesis phenomena.


Assuntos
Cádmio/toxicidade , Poluentes Químicos da Água/toxicidade , Peixe-Zebra/metabolismo , Animais , Relação Dose-Resposta a Droga , Dinâmica não Linear , Distribuição Tecidual
9.
Environ Res ; 156: 818-833, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28347490

RESUMO

Powerful scientific techniques have caused dramatic expansion of genetically modified crops leading to altered agricultural practices posing direct and indirect environmental implications. Despite the enhanced yield potential, risks and biosafety concerns associated with such GM crops are the fundamental issues to be addressed. An increasing interest can be noted among the researchers and policy makers in exploring unintended effects of transgenes associated with gene flow, flow of naked DNA, weediness and chemical toxicity. The current state of knowledge reveals that GM crops impart damaging impacts on the environment such as modification in crop pervasiveness or invasiveness, the emergence of herbicide and insecticide tolerance, transgene stacking and disturbed biodiversity, but these impacts require a more in-depth view and critical research so as to unveil further facts. Most of the reviewed scientific resources provide similar conclusions and currently there is an insufficient amount of data available and up until today, the consumption of GM plant products are safe for consumption to a greater extent with few exceptions. This paper updates the undesirable impacts of GM crops and their products on target and non-target species and attempts to shed light on the emerging challenges and threats associated with it. Underpinning research also realizes the influence of GM crops on a disturbance in biodiversity, development of resistance and evolution slightly resembles with the effects of non-GM cultivation. Future prospects are also discussed.


Assuntos
Meio Ambiente , Plantas Geneticamente Modificadas , Regulamentação Governamental , Política
10.
Environ Res ; 152: 308-314, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27833058

RESUMO

Despite of the fact that engine manufacturers develop a new technology to reduce exhaust emissions, insufficient attention given to particulate emissions. However, diesel exhaust particles are a major source of air-borne pollution, contain vast amount of polycyclic aromatic hydrocarbons (PAHs) and may have deleterious effects on the immune system, resulting in the induction and enhancement of pro-allergic processes. In the current study, vehicle emitted particles (VEP) from 2 different types of cars (diesel - D and gasoline - G) and locomotive (L) were collected. Overall, 129 four-week-old, male SPF-class Kunming mice were subcutaneously instilled with either low dose 100, 250 or high dose, 500mg/kg VEP and 15 mice were assigned as control group. The systemic toxicity was evaluated and alterations in the percentages of the CD3, CD4, CD8, CD16, CD25 expressing cells, basophils, eosinophils and neutrophils were determined. Basophil percentages were inversely associated with the PAH content of the VEPs, however basophil sensitization was more important than cell count in VEP exposure. Thus, the effects of VEP-PAHs emerge with the activation of basophils in an allergen independent fashion. Despite the increased percentage of CD4+ T cells, a sharp decrease in basophil counts at 500mg/kg of VEP indicates a decreased inhibitory effect of CD16+ monocytes on the proliferation of CD4+ T cell and suppressed polarization into a Th2 phenotype. Therefore, although the restrictions for vehicles emissions differ between countries, follow up studies and strict regulations are needed.


Assuntos
Poluentes Atmosféricos/toxicidade , Basófilos/efeitos dos fármacos , Basófilos/imunologia , Inflamação/imunologia , Material Particulado/toxicidade , Hidrocarbonetos Policíclicos Aromáticos/toxicidade , Emissões de Veículos/toxicidade , Animais , Automóveis , Inflamação/induzido quimicamente , Masculino , Camundongos , Federação Russa , Organismos Livres de Patógenos Específicos
11.
Part Fibre Toxicol ; 14(1): 22, 2017 06 24.
Artigo em Inglês | MEDLINE | ID: mdl-28646905

RESUMO

Extracellular matrix (ECM) is an extraordinarily complex and unique meshwork composed of structural proteins and glycosaminoglycans. The ECM provides essential physical scaffolding for the cellular constituents, as well as contributes to crucial biochemical signaling. Importantly, ECM is an indispensable part of all biological barriers and substantially modulates the interchange of the nanotechnology products through these barriers. The interactions of the ECM with nanoparticles (NPs) depend on the morphological characteristics of intercellular matrix and on the physical characteristics of the NPs and may be either deleterious or beneficial. Importantly, an altered expression of ECM molecules ultimately affects all biological processes including inflammation. This review critically discusses the specific behavior of NPs that are within the ECM domain, and passing through the biological barriers. Furthermore, regenerative and toxicological aspects of nanomaterials are debated in terms of the immune cells-NPs interactions.


Assuntos
Matriz Extracelular/efeitos dos fármacos , Sistema Imunitário/efeitos dos fármacos , Inflamação/induzido quimicamente , Nanopartículas/efeitos adversos , Animais , Matriz Extracelular/imunologia , Matriz Extracelular/metabolismo , Matriz Extracelular/patologia , Proteínas da Matriz Extracelular/metabolismo , Humanos , Sistema Imunitário/imunologia , Sistema Imunitário/metabolismo , Sistema Imunitário/patologia , Inflamação/imunologia , Inflamação/metabolismo , Inflamação/patologia , Mediadores da Inflamação/metabolismo , Medição de Risco , Transdução de Sinais/efeitos dos fármacos
12.
Am J Addict ; 26(4): 335-342, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28314070

RESUMO

BACKGROUND AND OBJECTIVES: The purpose of this study was to evaluate the extent of short-term memory impairment and schizophrenia-like symptoms in heavy and systematic cannabis users and the association between the severity of abuse and the longevity of its persistent symptoms after refraining from such use. METHODS: A complete psychiatric examination and a psychometric evaluation were performed in 48 solely cannabis users. Additionally, head hair samples were analyzed and the detected cannabinoids levels were correlated with the psychometric findings. RESULTS: A total of 33.3% (n = 16) of the total examined cannabis users were currently imprisoned. The years of abuse ranged from 1 to 35 years and the median daily dose was 5.84.4 gr and 4.84.0 gr for prisoners (n = 16) and non prisoners (n = 32), respectively. A total of 39.6% of the users experienced hallucinations (mostly auditory), 54.2% experienced delusions (mostly ideas of reference and persecution), 85.4% had organic brain dysfunction in a test addressing visual-motor functioning and visual perception skills, and all users (100%) were found to have organic brain dysfunction in a test of visual memory immediate recall. The cannabinoid metabolite levels in the hair samples were consistent with the reported history of substance abuse and total grams of consumption for the participants below 35 years old (p < .001). Statistically elevated cannabinoids levels were observed in users with auditory hallucinations compared to users without any hallucinations (p = .019). CONCLUSIONS: The existence of hallucinations, delusions, and organic brain dysfunction in heavy cannabis users seems to be associated with cannabinoid levels in hair. The continuation of persistent symptoms 3 months after the discontinuation of cannabis abuse, was a remarkable finding. SCIENTIFIC SIGNIFICANCE: We provide evidence that chronic and heavy cannabis abuse results in long-lasting brain dysfunction in all users and in long-lasting schizophrenia-like psychotic symptoms in more than half of all users. These findings suggest a reevaluation of the current classification of cannabis as a "soft narcotic" which erroneously, therefore, is typically considered harmless. (Am J Addict 2017;26:335-342).


Assuntos
Canabinoides/farmacocinética , Cannabis/efeitos adversos , Abuso de Maconha/psicologia , Memória de Curto Prazo/efeitos dos fármacos , Esquizofrenia/induzido quimicamente , Adulto , Feminino , Cabelo/metabolismo , Humanos , Masculino , Abuso de Maconha/complicações , Esquizofrenia/complicações , Esquizofrenia/diagnóstico , Tempo , Fatores de Tempo , Adulto Jovem
13.
Nanomedicine ; 13(3): 1021-1030, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-27884639

RESUMO

Polymeric nanoparticles were prepared from self-assembled amphiphilic N-vinylpyrrolidone polymers in aqueous media and evaluated as novel carriers of indomethacin, a non-steroidal, anti-inflammatory drug. It was determined that these nanoparticles could be created in spherical morphologies with sizes less than 100nm, narrow size distributions and high indomethacin contents(up to 35%) combined with high drug loading efficiencies(up to 95%). In cytotoxicity tests using the human embryonic stem cell derived fibroblasts (EBF-H9) and hepatocellular carcinoma cells (HepG2), the indomethacin-loaded polymeric nanoparticles showed higher cell viability compared to that of free indomethacin at the same concentration. The median LD50 values, determined by the Litchfield-Wilcoxon method, were 55-70mg/kg body weight depending on the polymer molecular design in both mice and rats. Based on the acquired results, these novel amphiphilic poly-N-vinylpyrrolidone nanoparticles can be considered as potential carriers for new, highly efficient, injectable drug delivery systems for hydrophobic drugs such as indomethacin.


Assuntos
Anti-Inflamatórios não Esteroides/administração & dosagem , Portadores de Fármacos/química , Indometacina/administração & dosagem , Nanopartículas/química , Povidona/química , Animais , Anti-Inflamatórios não Esteroides/farmacocinética , Anti-Inflamatórios não Esteroides/toxicidade , Portadores de Fármacos/toxicidade , Feminino , Células Hep G2 , Humanos , Indometacina/farmacocinética , Indometacina/toxicidade , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Nanopartículas/toxicidade , Povidona/toxicidade , Ratos , Ratos Wistar
14.
Environ Res ; 142: 479-85, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26264860

RESUMO

The study aims at investigating the characteristics (size distribution, active surface and metal content) of particles emitted by cars as a function of mileage using a novel methodology for characterizing particulate emissions captured by Exhaust Gas Suspension (EGS). EGS was obtained by passing the exhaust gases through a container of deionized water. EGS analysis was performed using laser granulometry, electron scanning microscopy, and high resolution mass spectrometry. Implications of the differences in key features of the emitted particles on population exposure were investigated using numerical simulation for estimating size-segregated PM deposition across human respiratory tract (HRT). It was found that vehicle mileage, age and the respective emissions class have almost no effect on the size distribution of the exhaust gas particulate released into the environment; about half of the examined vehicles with low mileage were found to release particles of aerodynamic diameter above 10 µm. The exhaust gas particulate detected in the EGS of all cars can be classified into three major size classes: (1) 0.1-5 µm - soot and ash particles, metals (Au, Pt, Pd, Ir); (2) 10-30 µm - metal (Cr, Fe, Cu, Zr, Ni) and ash particles; (3) 400-1,000 µm - metal (Fe, Cr, Pb) and ash particles. Newer vehicles with low mileage are substantial sources of soot and metal particles with median diameter of 200 nm with a higher surface area (up to 89,871.16 cm(2)/cm(3)). These tend to deposit in the lower part of the human respiratory tract.


Assuntos
Poluentes Atmosféricos/análise , Exposição Ambiental , Metais Pesados/análise , Veículos Automotores , Material Particulado/análise , Emissões de Veículos/análise , Exposição Ambiental/efeitos adversos , Exposição Ambiental/análise , Saúde Ambiental , Veículos Automotores/normas , Tamanho da Partícula , Federação Russa , Propriedades de Superfície , Urbanização
15.
J Strength Cond Res ; 29(1): 270-8, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25353080

RESUMO

The past 2-3 decades have seen an explosion in analytical areas related to "omic" technologies. These advancements have reached a point where their application can be and are being used as a part of exercise physiology and sport performance research. Such advancements have drastically enabled researchers to analyze extremely large groups of data that can provide amounts of information never before made available. Although these "omic" technologies offer exciting possibilities, the analytical costs and time required to complete the statistical approaches are substantial. The areas of exercise physiology and sport performance continue to witness an exponential growth of published studies using any combination of these techniques. Because more investigators within these traditionally applied science disciplines use these approaches, the need for efficient, thoughtful, and accurate extraction of information from electronic databases is paramount. As before, these disciplines can learn much from other disciplines who have already developed software and technologies to rapidly enhance the quality of results received when searching for key information. In addition, further development and interest in areas such as toxicogenomics could aid in the development and identification of more accurate testing programs for illicit drugs, performance enhancing drugs abused in sport, and better therapeutic outcomes from prescribed drug use. This review is intended to offer a discussion related to how bioinformatics approaches may assist the new generation of "omic" research in areas related to exercise physiology and toxicogenomics. Consequently, more focus will be placed on popular tools that are already available for analyzing such complex data and highlighting additional strategies and considerations that can further aid in developing new tools and data management approaches to assist future research in this field. It is our contention that introducing more scientists to how this type of work can complement existing experimental approaches within exercise physiology and sport performance will foster additional discussion and stimulate new research in these areas.


Assuntos
Desempenho Atlético/fisiologia , Pesquisa Biomédica/métodos , Biologia Computacional , Exercício Físico/fisiologia , Medicina Esportiva/métodos , Toxicogenética , Humanos
16.
Tumour Biol ; 35(10): 9549-56, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24957043

RESUMO

The cytochrome P450 CYP1A1 and CYP1B1 enzymes are phase I extrahepatic enzymes involved in the activation of pro-carcinogenic compounds to carcinogenic metabolites. Although differential overexpression of CYP1A1 and CYP1B1 has been documented at the messenger RNA (mRNA) and protein level, studies that have examined CYP1 expression by enzyme activity assays are limited. In the current study, the expression of CYP1A1 and CYP1B1 was investigated in a panel of human tumors of endometrial origin by quantitative reverse transcriptase PCR (qRT-PCR), Western blotting, and enzyme activity assays. The data revealed that approximately 36 % (5/14) and 43 % (6/14) of the endometrial tumors overexpressed CYP1A1 and CYP1B1 mRNA, whereas in 57 % of the endometrial tumors, CYP1 mRNA levels were downregulated. The mean mRNA levels of CYP1B1 and CYP1A1 in endometrial tumors did not show a significant difference compared to normal tissues (p > 0.05). Western blotting confirmed the qRT-PCR results and CYP1A1 and CYP1B1 proteins were shown to be downregulated in 7/14 (50 %) of the tumors and overexpressed in 4/14 (29 %) of the tumors. As regards to enzyme activity, 21 % (3/14) of the endometrial samples revealed elevated CYP1 activity levels across the tumor counterparts. Overall, the data suggest a putative downregulation of CYP1A1 and CYP1B1 expression in endometrial tumors, whereas overexpression of active CYP1 enzymes in 21 % of the tumors highlights the potential use of the latter enzymes as chemotherapeutic targets in endometrial cancer.


Assuntos
Biomarcadores Tumorais/análise , Citocromo P-450 CYP1A1/biossíntese , Citocromo P-450 CYP1B1/biossíntese , Neoplasias do Endométrio/enzimologia , Idoso , Western Blotting , Cromatografia Líquida de Alta Pressão , Citocromo P-450 CYP1A1/análise , Citocromo P-450 CYP1B1/análise , Neoplasias do Endométrio/patologia , Feminino , Humanos , Espectrometria de Massas , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transcriptoma
17.
Environ Res ; 134: 181-7, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25173049

RESUMO

PURPOSE: The aim of this study was to evaluate the exposure of rural residents (control group) and occupational exposed population group of sprayers to organophosphorus pesticides (OPs) by measuring their non-specific dialkylphosphate metabolites (DAPs) in hair and in urine samples. All subjects (n=120) were residents of the municipality of Ierapetra, an area of intensive cultivation in Crete, Greece. METHODS: The determined OPs metabolites were DMP, DEP, DETP and DEDTP. Two different approaches were used for the analysis of the collected samples; solid-liquid extraction with sonication for hair and liquid-liquid extraction for urine. Gas chromatography-mass spectrometry (GC-MS) analysis was performed after derivatization of the isolated analytes. RESULTS AND DISCUSSION: The detection rates of DMP, DEP and DETP for both control and sprayers groups were high in both matrices, ranging from 91% to 100%. DEDTP was detected only in 9% of sprayers hair samples, while its detection rates in urine samples ranged from 83% to 90% for both population groups. Data analysis revealed significantly higher sumDAPs levels in urine of sprayers than in the urine of control group (p<0.001) and this is justified since sampling occurred during spraying periods. SumDAPs levels in hair samples of the sprayers were also significantly higher than in the hair of control group (p<0.001), confirming the long-term exposure to OPs. SumDAPs found levels in urine and hair samples of subjects were significantly correlated (Spearman׳s rho=0.728, p<0.001). Our study confirmed the elevated levels of DAPs in hair and urine samples in occupationally exposed group of sprayers in comparison to control group, even detected levels were similar in logarithmic scale.


Assuntos
Monitoramento Ambiental , Cabelo/química , Fosfatos/análise , População Rural , Cromatografia Gasosa-Espectrometria de Massas , Grécia , Humanos , Limite de Detecção , Fosfatos/urina , Espectrometria de Massas por Ionização por Electrospray
18.
Int J Environ Health Res ; 24(1): 56-62, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-23544435

RESUMO

We assessed the acute effects of a 1-h exposure to second-hand smoke (SHS) on complete blood count (CBC) markers in a controlled simulated bar/restaurant environment. Nineteen adult never-smokers completed a 1-h .exposure to SHS at bar/restaurant levels, and a 1-h exposure to normal room air. Blood samples were collected at the baseline at 30 min during each exposure, and at 0, 0.5, 1, 2, 3, and 4 h after each exposure. The values of white blood cells (WBC) at 1 h (p = 0.010), 3 h (p = 0.040), and 4 h (p = 0.008) following SHS were significantly increased compared with the baseline values. Also, there was a positive association between the WBC and cotinine levels (r = 0.28, p = 0.007). A 1-h exposure to SHS at bar/restaurant levels significantly increased the WBC for at least 4 h following the exposure time. This effect of SHS on WBC has dose-response characteristics and should be considered to prescribing CBC.


Assuntos
Cotinina/sangue , Exposição Ambiental , Poluição por Fumaça de Tabaco/efeitos adversos , Adulto , Biomarcadores/sangue , Contagem de Células Sanguíneas , Cromatografia Líquida , Estudos Cross-Over , Monitoramento Ambiental , Feminino , Humanos , Masculino , Espectrometria de Massas , Restaurantes , Fatores de Tempo , Adulto Jovem
19.
Int J Environ Health Res ; 24(3): 189-94, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-23802614

RESUMO

Recent trials demonstrated that a single brief exposure to secondhand smoke (SHS) generates acute adverse health effects. We evaluated the acute (immediately after exposure) and short-term (0.5, 1, 2, 3 and 4 h after exposure) effects of SHS on cardiac autonomic control and myocardial integrity. Nineteen adult healthy never-smokers underwent a 1 h exposure to SHS at bar/restaurant levels and a 1 h control exposure. Heart rate variability (HRV), serum cotinine, and six cardiac protein markers were assessed before, during, and up to four hours following each exposure. SHS reduced the standard deviation of normal-to-normal intervals and increased cotinine levels, creatine kinase (CK)-MB, and myoglobin (p < 0.05). We conclude that acute exposure to SHS suppresses HRV and augments CK-MB and myoglobin. The SHS-induced elevations in CK-MB and myoglobin may reflect a generalized lytic state, especially of the cardiac muscle, which is apparent for at least 2 h following the SHS exposure.


Assuntos
Frequência Cardíaca/efeitos dos fármacos , Coração/efeitos dos fármacos , Exposição por Inalação/efeitos adversos , Miocárdio/metabolismo , Sistema Nervoso Simpático/efeitos dos fármacos , Poluição por Fumaça de Tabaco/efeitos adversos , Adulto , Biomarcadores/sangue , Cotinina/sangue , Interpretação Estatística de Dados , Coração/inervação , Frequência Cardíaca/fisiologia , Humanos , Exposição por Inalação/análise , Miocárdio/patologia , Mioglobina/sangue , Poluição por Fumaça de Tabaco/análise
20.
Biomed Rep ; 20(3): 37, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38343660

RESUMO

Proteasome inhibitor bortezomib is an anticancer agent approved for treatment of multiple myeloma and mantle cell lymphoma. However, its application in other types of cancer, primarily in solid tumors, is limited due to poor pharmacokinetics, inefficient tissue penetration, low stability and frequent adverse effects. In the present study, a novel micellar nano-scaled delivery system was manufactured, composed of amphiphilic poly(N-vinylpyrrolidone) nanoparticles loaded with bortezomib. Similar nanoparticles loaded with prothionamide, a drug without anticancer effect, were used as control. The size and zeta potential of the obtained polymeric micelles were measured by dynamic light scattering. Bortezomib-loaded micelles exhibited significant cytotoxic activity in vitro in monolayer tumor cell cultures (IC50 ~6.5 µg/ml) and in 3D multicellular tumor spheroids (IC50 ~8.5 µg/ml) of human glioblastoma cell lines U87 and T98G. Additionally, the toxic effects in vivo were studied in zebrafish Danio rerio embryos, with an estimated 50% lethal concentration of 0.1 mg/ml. Considering that bortezomib and other molecules from the class of proteasome inhibitors are potent antitumor agents, nanodelivery approach can help reduce adverse effects and expand the range of its applications for treatment of various oncological diseases.

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