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1.
Sci Total Environ ; 953: 176105, 2024 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-39245390

RESUMO

Wildland firefighters are exposed to metal(loid)s released during wildfires through vegetation combustion, which also promotes remobilization of accumulated anthropogenic metal(loid)s. Studies biomonitoring metal(loid)s exposure promoted exclusively by wildfire suppression activities are lacking. This work aimed to characterize, for the first time, the impact of real-life wildland firefighting operations on urinary levels of priority pollutant metal(loid)s [14 included in ATSDR, 11 in USEPA, and 4 in Human Biomonitoring for Europe Initiative priority lists] in firefighters. Spot urines were sampled pre-exposure (105 non-smokers, 76 smokers) and post-exposure to firefighting activities (20 non-smokers, 25 smokers); among those, paired samples were collected from 14 non-smoking and 24 smoking firefighters. Smokers displayed significantly higher baseline levels of zinc (28 %), lithium (29 %), cadmium (55 %), rubidium (13 %), and copper (20 %) than non-smokers. Following wildfire suppression, the concentration of the WHO potentially toxic metal(loid)s rose from 2 % to 3 % in smokers and 2 % to 5 % in non-smokers (up to 4 % for all firefighters and up to 5 % in paired samples). Levels of nickel (33-53 %), antimony (45-56 %), and cesium (40-47 %) increased significantly post-exposure in non-smokers (in all firefighters and in paired samples), whose urinary concentrations were generally more impacted by wildfire emissions than those of smokers. Arsenic (80 %) displayed the only significant increase post-exposure in smokers, being the best discriminant of exposure to wildfire emissions in these subjects. Significant positive correlations were found for age and/or career length with cadmium, lead, barium, strontium, and mercury, and for body mass index with arsenic. The reference/guidance values were exceeded for arsenic, zinc, cesium, nickel, antimony, cadmium, lead, thallium, mercury, copper, and cobalt in 1-90 % of firefighters suggesting augmented health risks due to wildfire combating and emphasizing the need of mitigation strategies. This study also provides biomonitoring data to help setting reference values for the occupationally exposed part of population.

2.
Environ Pollut ; 350: 123976, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38657893

RESUMO

The lack of knowledge regarding the extent of microbial contamination in Portuguese fitness centers (FC) puts attendees and athletes at risk for bioaerosol exposure. This study intends to characterize microbial contamination in Portuguese FC by passive sampling methods: electrostatic dust collectors (EDC) (N = 39), settled dust (N = 8), vacuum filters (N = 8), and used cleaning mops (N = 12). The obtained extracts were plated in selective culture media for fungi and bacteria. Filters, EDC, and mop samples' extracts were also screened for antifungal resistance and used for the molecular detection of the selected Aspergillus sections. The detection of mycotoxins was conducted using a high-performance liquid chromatograph (HPLC) system and to determine the cytotoxicity of microbial contaminants recovered by passive sampling, HepG2 (human liver carcinoma) and A549 (human alveolar epithelial) cells were employed. The results reinforce the use of passive sampling methods to identify the most critical areas and identify environmental factors that influence microbial contamination, namely having a swimming pool. The cardio fitness area presented the highest median value of total bacteria (TSA: 9.69 × 102 CFU m-2.day-1) and Gram-negative bacteria (VRBA: 1.23 CFU m-2.day-1), while for fungi it was the open space area, with 1.86 × 101 CFU m-2.day-1. Aspergillus sp. was present in EDC and in filters used to collect settled dust. Reduced azole susceptibility was observed in filters and EDC (on ICZ and VCZ), and in mops (on ICZ). Fumonisin B2 was the only mycotoxin detected and it was present in all sampling matrixes except settled dust. High and moderate cytotoxicity was obtained, suggesting that A549 cells were more sensitive to samples' contaminants. The observed widespread of critical toxigenic fungal species with clinical relevance, such as Aspergillus section Fumigati, as well as Fumonisin B2 emphasizes the importance of frequent and effective cleaning procedures while using shared mops appeared as a vehicle of cross-contamination.


Assuntos
Microbiologia do Ar , Monitoramento Ambiental , Fungos , Portugal , Humanos , Monitoramento Ambiental/métodos , Poluição do Ar em Ambientes Fechados/análise , Poluição do Ar em Ambientes Fechados/estatística & dados numéricos , Micotoxinas/análise , Poeira/análise , Células Hep G2 , Células A549 , Bactérias/isolamento & purificação
3.
Pharmaceutics ; 14(3)2022 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-35335868

RESUMO

Gold nanoparticles (AuNPs) are inorganic and biocompatible nanovehicles capable of conjugating biomolecules to enhance their efficacy in cancer treatment. The high and reactive surface area provides good advantages for conjugating active compounds. Two approaches were developed in this work to improve the Epigallocatechin-3-gallate (EGCG) antioxidant efficacy. AuNPs were synthesized by reducing gold salt with chitosan. One other nanosystem was developed by functionalizing AuNPs with cysteamine using the Turkevitch method. The physico-chemical characterization of EGCG conjugated in the two nanosystems-based gold nanoparticles was achieved. The in vitro toxic effect induced by the nanoconjugates was evaluated in pancreatic cancer cells, showing that encapsulated EGCG keeps its antioxidant activity and decreasing the BxPC3 cell growth. A significant cell growth inhibition was observed in 50% with EGCG concentrations in the range of 2.2 and 3.7 µM in EGCG-ChAuNPs and EGCG-Cyst-AuNPs nanoconjugates, respectively. The EGCG alone had to be present at 23 µM to induce the same cytotoxicity response. Caspase-3 activity assay demonstrated that the conjugation of EGCG induces an enhancement of BxPC3 apoptosis compared with EGCG alone. In conclusion, AuNPs complexes can be used as delivery carriers to increase EGCG antioxidant activity in cancer tissues.

4.
REME rev. min. enferm ; 23: e-1177, jan.2019.
Artigo em Inglês, Português | BDENF - Enfermagem, LILACS | ID: biblio-1005474

RESUMO

Objetivo: avaliar a contribuição de um programa de educação permanente semipresencial no conhecimento de enfermeiros sobre estomias intestinais de eliminação. Método: estudo quase-experimental, do tipo grupo único, antes e depois, realizado com 51 enfermeiros de três hospitais de grande porte do Piauí, no período de agosto a outubro de 2014, nas seguintes etapas: identificação dos enfermeiros, exposição dos objetivos e convite para participação na pesquisa, préteste, programa de educação permanente semipresencial e pós-teste. Resultados: a média do número de acertos dos enfermeiros no pré-teste 25,5 (dp=4,2) foi menor do que no pós-teste 31,5 (dp=3,0) e essa diferença foi estatisticamente significante (p=0,000). Conclusão: neste estudo, o programa de educação permanente semipresencial contribuiu para melhorar o conhecimento dos enfermeiros sobre estomias intestinais de eliminação.(AU)


Obcjetive: to evaluate the contribution of an in-person permanent education program on the knowledge of nurses on intestinal elimination. Method: a quasiexperimental, single-group, before and after study conducted with 51 nurses from three large hospitals in Piauí, from August to October 2014, in the following stages: identification of nurses, presentation of the objectives and invitation to participate in the research, pre-test, semi in-person permanent education program and posttest. Results: the mean number of hits by the nurses in the pre-test 25.5 (sd=4.2) was lower than in the post-test 31.5 (sd=3.0) and this difference was statistically significant (p=0.000). Conclusion: in this study, the semi in-person permanent education program contributed to improve nurse knowledge about intestinal elimination stomas.(AU)


Objetivo: evaluar la contribución de un programa de educación permanente semipresencial al conocimiento de los enfermeros sobre los estomas intestinales de eliminación. Método: estudio cuasi-experimental, tipo grupo único, antes y después, realizado con 51 enfermeros de tres hospitales grandes de Piauí, entre agosto y octubre de 2014, en las siguientes etapas: identificación de enfermeros, exposición de objetivos e invitación para participar en la investigación, prueba preliminar, programa de educación permanente semipresencial y prueba posterior. Resultados: el promedio del número de respuestas correctas en la prueba preliminar de 25,5 (dp=4,2) era inferior al de la prueba posterior 31,5 (dp=3,0) y esa diferencia era estadísticamente significante (p=0,000). Conclusión: en este estudio, el programa de educación permanente semipresencial contribuye a mejorar el conocimiento de los enfermeros sobre los estomas intestinales de eliminación.(AU)


Assuntos
Humanos , Estomia , Educação a Distância , Educação Continuada , Educação em Enfermagem
5.
Front Pharmacol ; 9: 1261, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30524273

RESUMO

Resveratrol (RES) is a natural polyphenolic non-flavonoid compound present in grapes, mulberries, peanuts, rhubarb and in several other plants. Numerous health effects have been related with its intake, such as anti-carcinogenic, anti-inflammatory and brain protective effects. The neuroprotective effects of RES in neurological diseases, such as Alzheimer's (AD) and Parkinson's (PD) diseases, are related to the protection of neurons against oxidative damage and toxicity, and to the prevention of apoptotic neuronal death. In brain cancer, RES induces cell apoptotic death and inhibits angiogenesis and tumor invasion. Despite its great potential as therapeutic agent for the treatment of several diseases, RES exhibits some limitations. It has poor water solubility and it is chemically instable, being degraded by isomerization once exposed to high temperatures, pH changes, UV light, or certain types of enzymes. Thus, RES has low bioavailability, limiting its biological and pharmacological benefits. To overcome these limitations, RES can be delivered by nanocarriers. This field of nanomedicine studies how the drug administration, pharmacokinetics, and pharmacodynamics are affected by the use of nanosized materials. The role of nanotechnology, in the prevention and treatment of neurological diseases, arises from the necessity to mask the physicochemical properties of therapeutic drugs to prolong the half-life and to be able to cross the blood-brain barrier (BBB). This can be achieved by encapsulating the drug in a nanoparticle (NP), which can be made of different kinds of materials. An increasing trend to encapsulate and direct RES to the brain has been observed. RES has been encapsulated in many different types of nanosystems, as liposomes, lipid and polymeric NPs. Furthermore, some of these nanocarriers have been modified with targeting molecules able to recognize the brain areas. Then, this article aims to overview the RES benefits and limitations in the treatment of neurological diseases, as the different nanotechnology strategies to overcome these limitations.

6.
J Toxicol Environ Health A ; 80(13-15): 630-640, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28679081

RESUMO

The aim of this study was to determine levels and risks due to inhalation exposure to polycyclic aromatic hydrocarbons (PAH) in different educational settings, namely for 3- to 5- year-old and 6- to 10-year-old children. Eighteen PAH (16 priority designated by US Environmental Protection Agency (USEPA) and dibenzo[a,l]pyrene and benzo[j]fluoranthene) were simultaneously collected in indoor and outdoor air at two Portuguese preschools (PS1-PS2) and five elementary schools (ES1-ES5) from March to May 2014. Indoor concentrations at PS and ES were significantly different, with total levels (∑PAHs) 0.721-15.9 ng/m3 at PS1-PS2 and 5.03-23.6 ng/m3 at ES1-ES5. The corresponding outdoor concentrations were, respectively, 1.22-32.7 ng/m3 and 2.6-31.5 ng/m3. Polycyclic aromatic hydrocarbons with 2-3 aromatic rings were predominantly emitted by indoor sources, while compounds with 4-6 aromatic rings were mainly generated by infiltration of ambient PAH pollution to indoors. Excess lifetime risks of lung cancer exceeded the World Health Organization (WHO) designated guideline of 10-5 in both types of schools (15-42-fold at PS; 15-52-fold at ES). However, total (sum of indoor and outdoor exposure) incremental lifetime cancer risks (ILCR) were below the USEPA level of 10-6 at all studied institutions and thus considered negligible. Finally, ILCR due to indoor exposure represented 60-75% and 70-85% of the total ILCR at PS and ES, respectively, thus indicating the need for development and implementation of indoor air quality guidelines in educations settings.


Assuntos
Poluição do Ar em Ambientes Fechados/análise , Exposição por Inalação/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Instituições Acadêmicas/estatística & dados numéricos , Poluição do Ar em Ambientes Fechados/efeitos adversos , Criança , Pré-Escolar , Humanos , Exposição por Inalação/efeitos adversos , Hidrocarbonetos Policíclicos Aromáticos/efeitos adversos , Portugal , Medição de Risco
7.
Sci Total Environ ; 592: 277-287, 2017 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-28319714

RESUMO

This work aims to characterize personal exposure of firefighters to polycyclic aromatic hydrocarbons (PAHs) in non-fire work environments (fire stations), and assesses the respective risks. Eighteen PAHs (16 considered by USEPA as priority pollutants, dibenzo[a,l]pyrene and benzo[j]fluoranthene) were monitored in breathing zones of workers at five Portuguese fire stations during a normal shift. The obtained levels of PAHs fulfilled all existent occupational exposure limits as well as air quality guidelines with total concentrations (ΣPAHs) in range of 46.8-155ngm-3. Light compounds (2-3 rings) were the most predominant congeners (74-96% of ΣPAHs) whereas PAHs with 5-6 rings accounted 3-9% of ΣPAHs. Fuel and biomass combustions, vehicular traffic emissions, and use of lubricant oils were identified as the main sources of PAHs exposure at the studied fire corporations. Incremental lifetime cancer risks were below the recommend USEPA guideline of 10-6 and thus negligible for all the studied subjects, but WHO health-based guideline level of 10-5 was exceeded (9-44 times) at all fire corporations. These results thus show that even during non-fire situations firefighters are exposed to PAHs at levels that may promote some adverse health outcomes; therefore the respective occupational exposures to these compounds should be carefully controlled.


Assuntos
Poluição do Ar/análise , Bombeiros , Exposição Ocupacional/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Humanos , Estados Unidos , United States Environmental Protection Agency
8.
J Hazard Mater ; 323(Pt A): 184-194, 2017 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-26997333

RESUMO

This work characterizes levels of eighteen polycyclic aromatic hydrocarbons (PAHs) in the breathing air zone of firefighters during their regular work shift at eight Portuguese fire stations, and the firefighters' total internal dose by six urinary monohydroxyl metabolites (OH-PAHs). Total PAHs (ΣPAHs) concentrations varied widely (46.4-428ng/m3), mainly due to site specificity (urban/rural) and characteristics (age and layout) of buildings. Airborne PAHs with 2-3 rings were the most abundant (63.9-95.7% ΣPAHs). Similarly, urinary 1-hydroxynaphthalene and 1-hydroxyacenaphthene were the predominant metabolites (66-96% ΣOH-PAHs). Naphthalene contributed the most to carcinogenic ΣPAHs (39.4-78.1%) in majority of firehouses; benzo[a]pyrene, the marker of carcinogenic PAHs, accounted with 1.5-10%. Statistically positive significant correlations (r≥0.733, p≤0.025) were observed between ΣPAHs and urinary ΣOH-PAHs for firefighters of four fire stations suggesting that, at these sites, indoor air was their major exposure source of PAHs. Firefighter's personal exposure to PAHs at Portuguese fire stations were well below the existent occupational exposure limits. Also, the quantified concentrations of post-shift urinary 1-hydroxypyrene in all firefighters were clearly lower than the benchmark level (0.5µmol/mol) recommended by the American Conference of Governmental Industrial Hygienists.


Assuntos
Poluentes Ocupacionais do Ar/análise , Poluição do Ar em Ambientes Fechados/análise , Monitoramento Ambiental/métodos , Bombeiros , Exposição por Inalação/análise , Exposição Ocupacional/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Humanos , Portugal , Medição de Risco
9.
ABC., imagem cardiovasc ; 29(2): 47-57, abr.-jun. 2016. ilus, graf
Artigo em Português | LILACS | ID: lil-786646

RESUMO

O trabalho consistiu em uma revisão bibliográfica sobre as alterações cardiovasculares em neonatos prematuros. Tais alterações têm elevada prevalência nas unidades de terapiaintensiva neonatal, bem como há necessidade frequente de tratamento específico e implicações prognósticas. A revisão foi realizada de forma não sistematizada, a partir das seguintesfontes de pesquisas: PubMed, BVS e Medline. Foram definidas as causas de tais alterações hemodinâmicas,os métodos frequentemente utilizados para sua detecção e propostas alternativas mais objetivas e eficientes nesta avaliação, enfatizando-se diferentes parâmetros ecocardiográficos bem como as limitações de cada método.


Assuntos
Humanos , Masculino , Feminino , Recém-Nascido , Canal Arterial/cirurgia , Ecocardiografia/métodos , Recém-Nascido Prematuro , Recém-Nascido de muito Baixo Peso , Aorta , Aorta Torácica , Hipotensão/complicações , Hipotensão/diagnóstico , Prevalência , Quimioterapia Combinada/métodos , Volume Sistólico
10.
Environ Pollut ; 208(Pt B): 382-94, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26552524

RESUMO

This work characterizes levels of polycyclic aromatic hydrocarbons (PAHs) in indoor and outdoor air of preschool environments, and assesses the respective risks for 3-5-years old children. Eighteen gaseous and particulate (PM1 and PM2.5) PAHs were collected indoors and outdoors during 63 days at preschools in Portugal. Gaseous PAHs accounted for 94-98% of total concentration (ΣPAHs). PAHs with 5-6 rings were predominantly found in PM1 (54-74% particulate ΣPAHs). Lighter PAHs originated mainly from indoor sources whereas congeners with 4-6 rings resulted mostly from outdoor emissions penetration (motor vehicle, fuel burning). Total cancer risks of children were negligible according to USEPA, but exceeded (8-13 times) WHO health-based guideline. Carcinogenic risks due to indoor exposure were higher than for outdoors (4-18 times).


Assuntos
Poluição do Ar em Ambientes Fechados/análise , Exposição Ambiental/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Poluentes Atmosféricos/análise , Poluição do Ar em Ambientes Fechados/estatística & dados numéricos , Pré-Escolar , Exposição Ambiental/estatística & dados numéricos , Feminino , Humanos , Masculino , Portugal , Instituições Acadêmicas
11.
Environ Sci Pollut Res Int ; 22(18): 13892-902, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25943510

RESUMO

As children represent one of the most vulnerable groups in society, more information concerning their exposure to health hazardous air pollutants in school environments is necessary. Polycyclic aromatic hydrocarbons (PAHs) have been identified as priority air pollutants due to their mutagenic and carcinogenic properties that strongly affect human health. Thus, this work aims to characterize levels of 18 selected PAHs in preschool environment, and to estimate exposure and assess the respective risks for 3-5-year-old children (in comparison with adults). Gaseous PAHs (mean of 44.5 ± 12.3 ng m(-3)) accounted for 87% of the total concentration (ΣPAHs) with 3-ringed compounds being the most abundant (66% of gaseous ΣPAHs). PAHs with 5 rings were the most abundant ones in the particulate phase (PM; mean of 6.89 ± 2.85 ng m(-3)) being predominantly found in PM1 (78% particulate ΣPAHs). Overall child exposures to PAHs were not significantly different between older children (4-5 years old) and younger ones (3 years old). Total carcinogenic risks due to particulate-bound PAHs indoors were higher than outdoor ones. The estimated cancer risks of both preschool children and the staff were lower than the United States Environmental Protection Agency (USEPA) threshold of 10(-6) but slightly higher than WHO-based guideline.


Assuntos
Poluentes Atmosféricos/análise , Exposição Ambiental , Hidrocarbonetos Policíclicos Aromáticos/análise , Adulto , Poluição do Ar em Ambientes Fechados/análise , Carcinógenos Ambientais/análise , Criança , Pré-Escolar , Substâncias Perigosas/análise , Humanos , Mutagênicos/análise , Medição de Risco , Estados Unidos , United States Environmental Protection Agency
12.
J Biomed Mater Res A ; 103(4): 1476-84, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25046528

RESUMO

The aim of this study was to develop a drug delivery system based on poly(lactic-co-glycolic acid) (PLGA) nanoparticles for an efficient and targeted action of the proteasome inhibitor bortezomib against pancreatic cancer cells. The PLGA nanoparticles were formulated with a poloxamer, and further surface-modified with transferrin for tumor targeting. The nanoparticles were characterized as polymer carriers of bortezomib, and the cellular uptake and growth inhibitory effects were evaluated in pancreatic cells. Cellular internalization of nanoparticles was observed in normal and cancer cells, but with higher uptake by cancer cells. The sustained release of the loaded bortezomib from PLGA nanoparticles showed cytotoxic effects against pancreatic normal and cancer cells. Noteworthy differential cytotoxicity was attained by transferrin surface-modified PLGA nanoparticles since significant cell growth inhibition by delivered bortezomib was only observed in cancer cells. These findings demonstrate that the ligand transferrin enhanced the targeted delivery of bortezomib-loaded PLGA nanoparticles to pancreatic cancer cells. These in vitro results highlight the transferrin surface-modified PLGA nanoparticles as a promising system for targeted delivery of anticancer drugs.


Assuntos
Ácido Láctico/química , Nanopartículas/química , Neoplasias Pancreáticas/patologia , Ácido Poliglicólico/química , Inibidores de Proteassoma/farmacologia , Transferrina/metabolismo , Ácidos Borônicos , Bortezomib , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Endocitose/efeitos dos fármacos , Humanos , Nanopartículas/ultraestrutura , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Pirazinas , Espectroscopia de Infravermelho com Transformada de Fourier , Telomerase/metabolismo
13.
Environ Sci Pollut Res Int ; 21(6): 4492-501, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24337991

RESUMO

Considering tobacco smoke as one of the most health-relevant indoor sources, the aim of this work was to further understand its negative impacts on human health. The specific objectives of this work were to evaluate the levels of particulate-bound PAHs in smoking and non-smoking homes and to assess the risks associated with inhalation exposure to these compounds. The developed work concerned the application of the toxicity equivalency factors approach (including the estimation of the lifetime lung cancer risks, WHO) and the methodology established by USEPA (considering three different age categories) to 18 PAHs detected in inhalable (PM10) and fine (PM2.5) particles at two homes. The total concentrations of 18 PAHs (ΣPAHs) was 17.1 and 16.6 ng m(-3) in PM10 and PM2.5 at smoking home and 7.60 and 7.16 ng m(-3) in PM10 and PM2.5 at non-smoking one. Compounds with five and six rings composed the majority of the particulate PAHs content (i.e., 73 and 78 % of ΣPAHs at the smoking and non-smoking home, respectively). Target carcinogenic risks exceeded USEPA health-based guideline at smoking home for 2 different age categories. Estimated values of lifetime lung cancer risks largely exceeded (68-200 times) the health-based guideline levels at both homes thus demonstrating that long-term exposure to PAHs at the respective levels would eventually cause risk of developing cancer. The high determined values of cancer risks in the absence of smoking were probably caused by contribution of PAHs from outdoor sources.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar em Ambientes Fechados/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Poluição por Fumaça de Tabaco/análise , Poluição do Ar em Ambientes Fechados/estatística & dados numéricos , Humanos , Exposição por Inalação/estatística & dados numéricos , Modelos Químicos , Medição de Risco , Poluição por Fumaça de Tabaco/estatística & dados numéricos
14.
Environ Sci Pollut Res Int ; 21(5): 3604-20, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24271728

RESUMO

Hospitals are considered as a special and important type of indoor public place where air quality has significant impacts on potential health outcomes. Information on indoor air quality of these environments, concerning exposures to particulate matter (PM) and related toxicity, is limited though. This work aims to evaluate risks associated with inhalation exposure to ten toxic metals and chlorine (As, Ni, Cr, Cd, Pb, Mn, Se, Ba, Al, Si, and Cl) in coarse (PM2.5-10) and fine (PM2.5) particles in a Portuguese hospital in comparison with studies representative of other countries. Samples were collected during 1 month in one urban hospital; elemental PM characterization was determined by proton-induced X-ray emission. Noncarcinogenic and carcinogenic risks were assessed according to the methodology provided by the United States Environmental Protection Agency (USEPA; Region III Risk-Based Concentration Table) for three different age categories of hospital personnel (adults, >20, and <65 years) and patients (considering nine different age groups, i.e., children of 1-3 years to seniors of >65 years). The estimated noncarcinogenic risks due to occupational inhalation exposure to PM2.5-bound metals ranged from 5.88 × 10(-6) for Se (adults, 55-64 years) to 9.35 × 10(-1) for As (adults, 20-24 years) with total noncarcinogenic risks (sum of all metals) above the safe level for all three age categories. As and Cl (the latter due to its high abundances) were the most important contributors (approximately 90 %) to noncarcinogenic risks. For PM2.5-10, noncarcinogenic risks of all metals were acceptable to all age groups. Concerning carcinogenic risks, for Ni and Pb, they were negligible (<1 × 10(-6)) in both PM fractions for all age groups of hospital personnel; potential risks were observed for As and Cr with values in PM2.5 exceeding (up to 62 and 5 times, respectively) USEPA guideline across all age groups; for PM2.5-10, increased excess risks of As and Cr were observed particularly for long-term exposures (adults, 55-64 years). Total carcinogenic risks highly (up to 67 times) exceeded the recommended level for all age groups, thus clearly showing that occupational exposure to metals in fine particles pose significant risks. If the extensive working hours of hospital medical staff were considered, the respective noncarcinogenic and carcinogenic risks were increased, the latter for PM2.5 exceeding the USEPA cumulative guideline of 10(-4). For adult patients, the estimated noncarcinogenic and carcinogenic risks were approximately three times higher than for personnel, with particular concerns observed for children and adolescents.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar em Ambientes Fechados/análise , Hospitais/estatística & dados numéricos , Material Particulado/análise , Adolescente , Adulto , Idoso , Arsênio/análise , Criança , Pré-Escolar , Monitoramento Ambiental , Humanos , Lactente , Exposição por Inalação/análise , Masculino , Metais/análise , Pessoa de Meia-Idade , Portugal/epidemiologia , Medição de Risco , Estados Unidos , Adulto Jovem
15.
J Toxicol Environ Health A ; 75(13-15): 909-19, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22788376

RESUMO

Hospitals are a specific indoor environment with highly susceptible individuals for whom indoor air pollution represents additional health risks. Particulate matter (PM) is one of the most health-relevant indoor pollutants due to its association with respiratory and cardiovascular diseases. Particles can also act as a carrier for various harmful organisms present in the air of hospitals, thus leading to airborne transmission of infectious diseases. Thus, the objective of this study was to characterize indoor PM collected in a hospital in consideration of concentration, size distribution, and elemental composition. Emission sources of indoor PM were indentified and risks associated with indoor PM estimated. Sampling was performed at radiology ward of a Portuguese urban hospital where PM10, PM(2.5), and PM1 were collected during a period of 4 wk; PM elemental composition was determined by proton-induced x-ray emission (PIXE) analysis. Data showed that indoor PM10 concentrations ranged from 13 to 58.8 µg/m³ and from 10.5 to 41.9 µg/m³ for PM(2.5). Fine particles constituted 77% of PM10, indicating that PM(2.5) made a significant contribution to indoor air quality at the hospital. PM1 ranged from 9.9 to 35.6 µg/m³, accounting for 93% of PM(2.5). PIXE identified 21 elements in PM, including health-hazardous metals (manganese, iron, copper, and vanadium) and carcinogenic elements (nickel, chromium, arsenic, and lead). However, no significant indoor source of PM emissions was identified, while outdoor air was the major contributor of indoor particles. Further, no significant risks existed through PM10 inhalation for population at the respective hospital.


Assuntos
Poluentes Atmosféricos/química , Poluição do Ar em Ambientes Fechados , Hospitais Urbanos , Metais/análise , Material Particulado/química , Adulto , Poluentes Atmosféricos/análise , Poluentes Atmosféricos/toxicidade , Arsênio/análise , Arsênio/toxicidade , Criança , Intoxicação por Metais Pesados , Humanos , Lactente , Recém-Nascido , Metais Pesados/análise , Metais Pesados/toxicidade , Tamanho da Partícula , Material Particulado/análise , Material Particulado/toxicidade , Intoxicação/etiologia , Portugal/epidemiologia , Medição de Risco , Espectrometria por Raios X , Fatores de Tempo , Saúde da População Urbana
16.
Nanomedicine (Lond) ; 6(1): 79-87, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21182420

RESUMO

AIMS: Polysaccharide nanoparticles were studied as drug delivery vehicles for chemopreventive agents. MATERIALS & METHODS: Green tea polyphenol epigallocatechin-3-gallate (EGCG) was incorporated into a carbohydrate matrix of gum arabic and maltodextrin with an encapsulation efficiency of approximately 85%. RESULTS: Encapsulated EGCG retained its biological activity, reducing the cell viability and inducing apoptosis of Du145 prostate cancer cells. Clonogenic assay demonstrated that encapsulation of EGCG enhanced its inhibitory effect on cell proliferation (10-20%) at lower concentrations (1-2 µM), compared with free EGCG. CONCLUSION: This study highlights the use of polysaccharide nanoparticles in chemoprevention as they can be used to deliver natural antioxidants capable of inhibiting steps of the tumorigenesis process.


Assuntos
Anticarcinógenos/administração & dosagem , Anticarcinógenos/uso terapêutico , Carcinoma/prevenção & controle , Catequina/análogos & derivados , Nanopartículas/química , Neoplasias da Próstata/prevenção & controle , Apoptose/efeitos dos fármacos , Caspase 3/metabolismo , Catequina/administração & dosagem , Catequina/uso terapêutico , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Quimioprevenção , Goma Arábica/química , Humanos , Masculino , Polissacarídeos/química , Chá/química
17.
Braz. j. infect. dis ; 7(2): 126-128, Apr. 2003. tab
Artigo em Inglês | LILACS | ID: lil-351156

RESUMO

Although AIDS patients in other countries are frequently diagnosed as having atypical mycobacterial infection, in Southern Brazil there is a clinical impression that Mycobacterium tuberculosis is the rule rather than the exception. We made a retrospective review of cultures for mycobacteria at our hospital in order to determine the frequency of atypical mycobacteria and Mycobacterium tuberculosis in hospitalised patients in Porto Alegre, Brazil. Mycobacterium tuberculosis was the most frequent isolate (79.9 percent), regardless of HIV serostatus. Only 1.5 percent of the cultures yielded atypical mycobacteria, all of which in AIDS patients. Mycobacterium tuberculosis was diagnosed in most of the HIV-infected patients (81.2 percent). We conclude that Mycobacterium tuberculosis is frequent in both HIV infected and non-HIV infected patients in this part of the country


Assuntos
Humanos , Masculino , Feminino , Adulto , Infecções Oportunistas Relacionadas com a AIDS , Mycobacterium tuberculosis , Tuberculose Pulmonar , Infecções Oportunistas Relacionadas com a AIDS , Brasil , Soropositividade para HIV , Infecções por Mycobacterium não Tuberculosas , Micobactérias não Tuberculosas , Prevalência , Estudos Retrospectivos , Tuberculose Pulmonar
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