356 research outputs found
Exposure of thermoelectric power-plant workers to volatile organic compounds from fuel oil: Genotoxic and cytotoxic effects in buccal epithelial cells
Copyright © 2012 Elsevier B.V. All rights reserved.Thermoelectric power-plant workers are constantly exposed to high levels of potentially genotoxic gaseous substances, such as volatile organic compounds (VOCs) from the combustion of fuel oil or the processing of naphtha. The aim of the present study was to estimate the association between such occupational exposure and the frequency of micronucleated cells and cells with other nuclear anomalies. Buccal epithelial cells were collected from a total of 44 power-plant workers (exposed group) and 47 administrative workers (non-exposed group), and examined for the frequency of micronucleated cells (MNC) and of cells with other nuclear anomalies (ONA: pyknosis, karyolysis, and karyorrhexis) by means of the micronucleus assay. The frequencies of MNC and ONA per 1000 cells in the exposed group (1.8‰ and 82.4‰, respectively) were significantly higher than in the non-exposed group (0.2‰ and 58.3‰, respectively). The exposed group had a twelve-fold increase in risk for formation of MNC compared with non-exposed individuals (RR = 12.1; 95% CI, 5.0–29.2; P < 0.001). The confounding factors analyzed (age, smoking status, alcohol consumption, and mouthwash use) did not show any significant association with the frequency of MNC or ONA. The findings of this study show that workers from power plants exposed to VOCs have a significantly elevated risk for DNA damage. Therefore, bio-monitoring of DNA damage is recommended for this group of workers
The Planetary Health Diet and Its Association with Asthma and Airway Inflammation in School-Aged Children
Poor dietary choices have been rising concurrently with an increase in asthma prevalence, especially in children. Dietary indexes that simultaneously measure the healthiness and sustainability of dietary patterns have emerged to address the dual concerns of human and planetary health. Accordingly, we aimed to evaluate adherence to a sustainable dietary pattern and its impact on airway inflammation and asthma. In this study, 660 school-aged children (49.1% females, 712 years) were considered. A cross-sectional analysis was performed to assess the association between diet and asthma and airway inflammation according to overweight/obesity. Diet was evaluated through the Planetary Health Diet Index (PHDI). Higher scores represent a healthier and more sustainable diet. Three definitions of asthma were considered based on a self-reported medical diagnosis, symptoms, asthma medication, measured lung function, and airway reversibility. Airway inflammation was assessed by exhaled fractional nitric oxide (eNO). We considered two categories of body mass index: non-overweight/non-obese and overweight/obese. The associations between diet with asthma and airway inflammation were estimated using adjusted binary logistic regressions. The odds of having airway inflammation decreased with the increase in PHDI score. Moreover, children in the non-overweight/non-obesity group in the fourth quartile of the PHDI had lower odds of having airway inflammation compared to children in the first quartile. Our study indicates that a healthier and sustainable diet is associated with lower levels of eNO, but only among children without overweight/obesity.</jats:p
Permeability coefficients and vapor pressure determination for fragrance materials
Objective This study aims to correlate new experimental data relevant to the description of the combined evaporation/permeation process of a perfume applied onto the skin. Methods The vapor pressure data was measured by thermogravimetric analysis (TG‐DTA). The Antoine constants and the Clarke & Glew parameters were determined for the same set of fragrance molecules to describe its low vapor pressures at new temperature ranges. The permeability coefficient of a set of 14 fragrance molecules in ethanolic solution was determined by Franz diffusion cell experiments, using porcine skin. The samples were analyzed by gas chromatography with a flame ionization detector (GC/FID) and high‐performance liquid chromatography with UV visible detector (HPLC/UV). A QSAR model was proposed to correlate the experimental data. Results The Antoine constants were determined and presented low standard deviations. The Clarke & Glew physically significant parameters were obtained along with its statistical analysis. The fitting is good since the magnitude order is in accordance with the literature, associated with the low correlation between the estimated parameters and low standard deviations. The presented correlation, based on a mixture using only ethanol as solvent, showed better results than previous QSAR models with a standard relative deviation (σr) of 0.190, a standard error (SE) of 0.397, and a determination coefficient (R2) of 0.7786. Conclusion The dataset is still small compared to larger and more general QSAR models; however, it is much more specific as to the type of solvent and class of materials studied. This work represents an advance for the modeling of the perfume diffusion process since it specifies important properties that until then had been treated in a more general way.info:eu-repo/semantics/acceptedVersio
Sugarcane light-colored lignin: a renewable resource for sustainable beauty
Lignin has emerged as a promising eco-friendly multifunctional ingredient for cosmetic applications, due to its ability to protect against ultraviolet radiation and its antioxidant and antimicrobial properties. However, its typical dark color and low water solubility limit its application in cosmetics. This study presents a simple process for obtaining light-colored lignin (LCLig) from sugarcane bagasse (SCB) alkaline black liquor, involving an oxidation treatment with hydrogen peroxide, followed by precipitation with sulfuric acid. The physico-chemical characterization, antioxidant and emulsifying potential of LCLig, and determination of its safety and stability in an oil-in-water emulsion were performed. A high-purity lignin (81.6%) with improved water solubility was obtained, as a result of the balance between the total aromatic phenolic units and the carboxylic acids. In addition, the antioxidant and emulsifying capacities of the obtained LCLig were demonstrated. The color reduction treatment did not compromise the safety of lignin for topical cosmetic applications. The emulsion was stable in terms of organoleptic properties (color, pH, and viscosity) and antioxidant activity over 3 months at 4, 25, and 40 °C.info:eu-repo/semantics/publishedVersio
Immobilization of streptavidin on a plasmonic Au-TiO2 thin film towards an LSPR biosensing platform
Optical biosensors based on localized surface plasmon resonance (LSPR) are the future of label-free detection methods. This work reports the development of plasmonic thin films, containing Au nanoparticles dispersed in a TiO2 matrix, as platforms for LSPR biosensors. Post-deposition treatments were employed, namely annealing at 400 °C, to develop an LSPR band, and Ar plasma, to improve the sensitivity of the Au-TiO2 thin film. Streptavidin and biotin conjugated with horseradish peroxidase (HRP) were chosen as the model receptor–analyte, to prove the efficiency of the immobilization method and to demonstrate the potential of the LSPR-based biosensor. The Au-TiO2 thin films were activated with O2 plasma, to promote the streptavidin immobilization as a biorecognition element, by increasing the surface hydrophilicity (contact angle drop to 7°). The interaction between biotin and the immobilized streptavidin was confirmed by the detection of HRP activity (average absorbance 1.9 ± 0.6), following a protocol based on enzyme-linked immunosorbent assay (ELISA). Furthermore, an LSPR wavelength shift was detectable (0.8 ± 0.1 nm), resulting from a plasmonic thin-film platform with a refractive index sensitivity estimated to be 33 nm/RIU. The detection of the analyte using these two different methods proves that the functionalization protocol was successful and the Au-TiO2 thin films have the potential to be used as an LSPR platform for label-free biosensors.Portuguese Foundation for Science and Technology (FCT) in the framework of the Strategic Funding UIDB/04650/2020, UIDB/04050/2020, and UID/EMS/00285/2020, and by the projects NANO4BIO: POCI-01-0145-FEDER-032299, with FCT reference PTDC/FIS-MAC/32299/2017, and CO2Plasmon, with FCT reference EXPL/CTM-REF/0750/2021. Patrícia Pereira-Silva, Diana I. Meira, and Diogo Costa acknowledge FCT for their Ph.D. scholarships, 2020.08235.BD, SFRH/BD/143262/2019, and SFRH/BD/136279/2018, respectively. Augusto Costa-Barbosa also acknowledges FCT for his Ph.D. scholarships SFRH/BD/133513/2017 and COVID/BD/152169/2021. The authors would like to express their gratitude to Nuno P. Barradas (C2TN, University of Lisbon) and Eduardo Alves (IPFN, University of Lisbon) for RBS measurements and analysis
Projections of Brazilian biomes resilience and socio-environmental risks to climate change
Climate change has been considered, at a global level, as one of the main anthropogenic drivers of environmental transformation, especially on biomes, ecosystems and the most vulnerable population. In this regard, the concept of resilience has been widely used in ecology to explain the ecosystem transition thresholds by which forests and other habitats are able to restructure in the face of various external disturbances. However, the concept of resilience in facing climate change impacts and risks through the lens of socio-environmental risks in Brazil is still underdeveloped, especially at the biome level. This article uses the theory of critical transitions to ecological niche distribution modeling in future global warming scenarios by the end of the century, in order to highlight the change in ecological resilience of the Amazon, Caatinga, Cerrado, Atlantic Forest and Pampa biomes, and how the changes in resilience can lead to an increased exposure, vulnerabilities and risks to socio-environmental security. This article shows how an interdisciplinary approach bringing together modeling of biome resilience may be a tool to support decision making and public policies on mitigation and adaptation to climate change and reduce risks to socio-environmental security.Climate change has been considered, at a global level, as one of the main anthropogenic drivers of environmental transformation, especially on biomes, ecosystems and the most vulnerable population. In this regard, the concept of resilience has been widely used in ecology to explain the ecosystem transition thresholds by which forests and other habitats are able to restructure in the face of various external disturbances. However, the concept of resilience in facing climate change impacts and risks through the lens of socio-environmental risks in Brazil is still underdeveloped, especially at the biome level. This article uses the theory of critical transitions to ecological niche distribution modeling in future global warming scenarios by the end of the century, in order to highlight the change in ecological resilience of the Amazon, Caatinga, Cerrado, Atlantic Forest and Pampa biomes, and how the changes in resilience can lead to an increased exposure, vulnerabilities and risks to socio-environmental security. This article shows how an interdisciplinary approach bringing together modeling of biome resilience may be a tool to support decision making and public policies on mitigation and adaptation to climate change and reduce risks to socio-environmental security
Specific Immunoassays for Placental Alkaline Phosphatase As a Tumor Marker
Human placental (hPLAP) and germ cell (PLAP-like) alkaline phosphatases are polymorphic and heat-stable enzymes. This study was designed to develop specific immunoassays for quantifying hPLAP and PLAP-like enzyme activity (EA) in sera of cancer patients, pregnant women, or smokers. Polyclonal sheep anti-hPLAP antibodies were purified by affinity chromatography with whole hPLAP protein (ICA-PLAP assay) or a synthetic peptide (aa 57–71) of hPLAP (ICA-PEP assay); the working range was 0.1–11 U/L and cutoff value was 0.2 U/L EA for nonsmokers. The intra- and interassay coefficients of variation were 3.7%–6.5% (ICA-PLAP assay) and 9.0%–9.9% (ICA-PEP assay). An insignificant cross-reactivity was noted for high levels of unheated intestinal alkaline phosphatase in ICA-PEP assay. A positive correlation between the regression of tumor size and EA was noted in a child with embryonal carcinoma. It can be concluded that ICA-PEP assay is more specific than ICA-PLAP, which is still useful to detect other PLAP/PLAP-like phenotypes
Insuficiência renal aguda nefrotóxica: prevalência, evolução clínica e desfecho
INTRODUCTION: Nephrotoxic acute renal failure (ARF) is a frequent and important cause of morbidity and mortality.
OBJECTIVE: To assess the prevalence, clinical course, and outcome of nephrotoxic ARF.
PATIENTS AND METHODS: Historical cohort carried out in a tertiary school hospital from February to November, 1997. Patients over 12 years of age, diagnosed with ARF, and followed up by a team of nephrologists were included. The exclusion criteria were as follows: renal transplantation, chronic renal failure, dialysis due to exogenous poisoning, and those transferred to hospital during treatment.
RESULTS: Of the 234 patients followed up, 12% had nephrotoxic ARF and 24% multifactorial ARF associated with the use of nephrotoxic drugs. The most prevalent comorbidities were as follows: hypertension, hepatopathy, neoplasias, congestive heart failure, and diabetes mellitus. Fifteen percent of the patients required dialysis, and the most commonly used type was continuous venovenous hemodialysis; 42% of the patients were oliguric; 44.7% died; and 33% recovered renal function. The most prevalent nephrotoxic drugs were antibiotics, nonsteroidal anti-inflammatory drugs, and radiographical contrast media. In order of frequency, the nephrotoxic drugs were as follows: vancomycin, aminoglycosides, acyclovir, chemotherapy agents, and radiographical contrast media. In multivariate analysis, hepatopathy was the only statistically significant variable (p = 0.03, CI = 1.08 to 6.49). The comparison of non-nephrotoxic and nephrotoxic ARF showed an increase in mortality proportional to the length of hospitalization.
CONCLUSION: Nephrotoxic ARF is common, serious, and must be continuously monitored both in hospital and on an outpatient basis.INTRODUÇÃO: A insuficiência renal aguda (IRA) nefrotóxica é frequente e importante causa de morbimortalidade.
OBJETIVO: Avaliar a prevalência, o curso clínico e o desfecho da IRA nefrotóxica.
PACIENTES e MÉTODOS: Coorte histórica realizada em um hospital de ensino terciário, no período de fevereiro a novembro de 1997. Foram incluídos pacientes acima de 12 anos, com diagnóstico de IRA, acompanhados pela equipe de Interconsulta de Nefrologia. Foram excluídos transplantados renais, portadores de insuficiência renal crônica, dialisados por intoxicação exógena e aqueles transferidos de hospital durante o tratamento.
RESULTADOS: Dos 234 pacientes acompanhados, 12% apresentaram IRA nefrotóxica e 24%, IRA multifatorial associada ao uso de drogas nefrotóxica. Entre as comorbidades mais prevalentes, estão hipertensão arterial, hepatopatias, neoplasias, insuficiência cardíaca congestiva e diabetes mellitus. Quinze por cento necessitaram de diálise, e o tipo mais frequentemente usado foi hemodiálise venovenosa contínua; 42% eram oligúricos, 44,7% evoluíram para óbito e 33% recuperaram a função renal. Antibióticos, AINH e contraste radiológico foram as drogas nefrotóxicas mais prevalentes.Os medicamentos nefrotóxicos implicados foram, em ordem de frequência, vancomicina, aminoglicosídeos, aciclovir, quimioterápicos e contraste radiológico. Hepatopatia foi a única variável com significância estatística (p = 0,03, IC = 1,08 a 6,49) em análise multivariada. Na comparação entre IRA nefrotóxica e não nefrotóxica, houve aumento da mortalidade proporcionalmente aos dias de internação.
CONCLUSÃO: IRA nefrotóxica é frequente, grave e deve ser continuamente monitorada, tanto ambulatorialmente quanto no ambiente intra-hospitalar
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