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1.
Nanomaterials (Basel) ; 12(14)2022 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-35889559

RESUMO

In the frame of the nanoarchitectonic concept, the objective of this study was to develop simple and easy methods to ensure the preparation of polymorphic HfO2 thin film materials (<200 nm) having the best balance of patterning potential, reproducibility and stability to be used in optical, sensing or electronic fields. The nanostructured HfO2 thin films with micropatterns or continuous morphologies were synthesized by two different methods, i.e., the micropatterning of sol-gel solutions by deep ultraviolet (DUV) photolithography or the electrophoretic deposition (EPD) of HfO2 nanoparticles (HfO2-NPs). Amorphous and monoclinic HfO2 micropatterned nanostructured thin films (HfO2-DUV) were prepared by using a sol-gel solution precursor (HfO2-SG) and spin-coating process following by DUV photolithography, whereas continuous and dense monoclinic HfO2 nanostructured thin films (HfO2-EPD) were prepared by the direct EPD of HfO2-NPs. The HfO2-NPs were prepared by a hydrothermal route and studied through the changing aging temperature, pH and reaction time parameters to produce nanocrystalline particles. Subsequently, based on the colloidal stability study, suspensions of the monoclinic HfO2-NPs with morphologies near spherical, spindle- and rice-like shapes were used to prepare HfO2-EPD thin films on conductive indium-tin oxide-coated glass substrates. Morphology, composition and crystallinity of the HfO2-NPs and thin films were investigated by powder and grazing incidence X-ray diffraction, scanning electron microscopy, transmission electron microscopy and UV-visible spectrophotometry. The EPD and DUV photolithography performances were explored and, in this study, it was clearly demonstrated that these two complementary methods are suitable, simple and effective processes to prepare controllable and tunable HfO2 nanostructures as with homogeneous, dense or micropatterned structures.

2.
Int Arch Occup Environ Health ; 94(4): 751-761, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33404731

RESUMO

OBJECTIVE: To determine long-term predictors of bronchial hyperresponsiveness (BHR) and forced expiratory volume in one second (FEV1) decline. METHODS: A longitudinal study in 110 bakers in 4 industrial bakeries and 38 non-exposed workers was conducted at the workplace with a mean of 3.3 visits per subject over a period of 13 years and a mean duration of follow-up of 6 years in bakers and 8 years in non-exposed subjects. A respiratory health questionnaire was administered; occupational allergen skin prick tests, spirometry and a methacholine bronchial challenge test were performed at each visit. In each bakery, full-shift dust samples of the inhalable fraction were obtained in order to assess the exposure of each job assignment. The repeated measurements of BHR and FEV1 were analyzed using mixed effects logistic and linear regression models in subjects seen at least twice. RESULTS: BHR, respiratory symptoms and their simultaneous occurrence depended on the duration of exposure. FEV1 significantly decreased with duration of exposure and BHR at a preceding visit. This result persisted when adjusting for the effect of BHR at the current visit. The measured exposure levels were not a significant predictor for any outcome. Occupational sensitization was only a predictor of a decline in FEV1 when duration of exposure was not included. CONCLUSION: In flour-exposed industrial bakers, length of exposure and smoking are long-term determinants of BHR and of the decrease in FEV1. BHR at a preceding visit predicted lower FEV1 even when accounting for the effect of BHR at the current visit.


Assuntos
Hiper-Reatividade Brônquica/epidemiologia , Hiper-Reatividade Brônquica/fisiopatologia , Volume Expiratório Forçado , Exposição Ocupacional/efeitos adversos , Adulto , Poeira , Feminino , França/epidemiologia , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Fumar/efeitos adversos , Inquéritos e Questionários , Adulto Jovem
3.
Arch Environ Occup Health ; 75(4): 191-200, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-30880640

RESUMO

This study investigated the plant features associated with increased irritation symptoms and levels of inflammation markers among compost workers (CWs). Ninety CWs were followed over 18 months, using questionnaires on respiratory symptoms, fractional exhaled nitric oxide measurements, spirometry, a methacholine bronchial challenge test, and quantification of specific immunoglobulins E (IgE) and G. CWs in plants processing the highest quantities of waste exhibited more airway irritation symptoms. So did the CWs in partially and fully indoor plants as compared to those in plants entirely outdoors. Working in sewage sludge versus green waste plants and having a high level of exposure were associated with higher levels of different IgE. The duration of employment decreased the FEV1 by 16 ml per year. Working in an indoor plant is linked to symptoms and inflammation markers in CWs.


Assuntos
Poluentes Ocupacionais do Ar/efeitos adversos , Hiper-Reatividade Brônquica/etiologia , Compostagem , Exposição Ocupacional , Plantas , Adulto , Testes de Provocação Brônquica , Humanos , Masculino , Pessoa de Meia-Idade , Espirometria , Inquéritos e Questionários
4.
ACS Appl Mater Interfaces ; 11(40): 37302-37312, 2019 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-31512470

RESUMO

New paradigms are required in microelectronics when the transistor is in its downscaling limit and integration of materials presenting functional properties not available in classical silicon is one of the promising alternatives. Here, we demonstrate the possibility to grow La0.67Sr0.33MnO3 (LSMO) functional materials on amorphous substrates with properties close to films grown on single-crystalline substrates using a two-dimensional seed layer. X-ray diffraction and electron backscatter diffraction mapping demonstrate that the Ca2Nb3O10- nanosheet (NS) layer induces epitaxial stabilization of LSMO films with a strong out-of-plane (001) texture, whereas the growth of LSMO films on uncoated glass substrates exhibits a nontextured polycrystalline phase. The magnetic properties of LSMO films deposited on NS are similar to those of the LSMO grown on SrTiO3 single-crystal substrates in the same conditions (which is used as a reference in this work). Moreover, transport measurements take advantages of the texture and polycrystalline properties to induce low-field magnetoresistance at low temperature and also a high value of 40% magnetoresistance from 10 to 300 K, making it interesting for sensor applications. Therefore, the NS seed layer offers new perspectives for the integration of functional materials grown at moderate temperatures on any substrate, which will be the key for the development of oxitronics.

5.
JMIR Res Protoc ; 8(8): e13744, 2019 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-31376276

RESUMO

BACKGROUND: Exposure to aerosols from metalworking fluids (MWF) has previously been related to a series of adverse health outcomes (eg, cancer, respiratory diseases). Our present epidemiological study focuses on occupational exposures to MWF and a panel of exposure and effect biomarkers. We hypothesize that these health outcomes are caused by particle exposure that generates oxidative stress, leading to airway inflammation and ultimately to chronic respiratory diseases. We aimed to assess whether MWF exposure, in particular as characterized by its oxidative potential, is associated with biomarkers of oxidative stress and inflammation as well as genotoxic effects. OBJECTIVE: The ultimate goal is to develop exposure reduction strategies based on exposure determinants that best predict MWF-related health outcomes. The following relationships will be explored: (1) exposure determinants and measured exposure; (2) occupational exposure and preclinical and clinical effect markers; (3) exposure biomarkers and biomarkers of effect in both exhaled breath condensate and urine; and (4) biomarkers of effect, genotoxic effects and respiratory symptoms. METHODS: At least 90 workers from France and Switzerland (30 controls, 30 exposed to straight MWF and 30 to aqueous MWF) were followed over three consecutive days after a nonexposed period of at least two days. The exposure assessment is based on MWF, metal, aldehyde, and ultrafine particle number concentrations, as well as the intrinsic oxidative potential of aerosols. Furthermore, exposure biomarkers such as metals, metabolites of polycyclic aromatic hydrocarbons and nitrosamine are measured in exhaled breath condensate and urine. Oxidative stress biomarkers (malondialdehyde, 8-isoprostane, 8-hydroxy-2'-deoxyguanosine, nitrates, and nitrites) and exhaled nitric oxide, an airway inflammation marker, are repeatedly measured in exhaled breath condensate and urine. Genotoxic effects are assessed using the buccal micronucleus cytome assay. The statistical analyses will include modelling exposure as a function of exposure determinants, modelling the evolution of the biomarkers of exposure and effect as a function of the measured exposure, and modelling respiratory symptoms and genotoxic effects as a function of the assessed long-term exposure. RESULTS: Data collection, which occurred from January 2018 until June 2019, included 20 companies. At the date of writing, the study included 100 subjects and 29 nonoccupationally exposed controls. CONCLUSIONS: This study is unique as it comprises human biological samples, questionnaires, and MWF exposure measurement. The biomarkers collected in our study are all noninvasive and are useful in monitoring MWF exposed workers. The aim is to develop preventative strategies based on exposure determinants related to health outcomes. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/13744.

6.
Inorg Chem ; 58(2): 1317-1329, 2019 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-30596502

RESUMO

Microcrystalline core-shell powders of lanthanide-based coordination polymers with general chemical formula ([Ln(cpbOH)]∞)1- x@([Ln'(cpbOH)]∞) x with Hcpb = 1,4-carboxyphenylboronic acid have been synthesized and structurally characterized. Their luminescent properties have been studied. They are drastically different from those of heterolanthanide coordination polymers, also called "molecular alloys", that present the same crystal structure and chemical composition. Study of the photophysical properties of core-shell lanthanide-based coordination polymers reveals that it is possible to control efficiently the intermetallic energy transfers between lanthanide ions. Furthermore, multiemissive compounds, under unique irradiation, in both visible and infrared regions are easily feasible. Core-shell microstructured lanthanide-based coordination polymers have also been prepared with terephthalic (H2bdc) and trimesic (H3tma) acids as ligands for evidencing that lanthanide-ion-based coordination compounds are excellent candidates for 3D molecular epitaxial growth.

7.
BMC Pulm Med ; 18(1): 113, 2018 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-29996808

RESUMO

BACKGROUND: The natural history of airway inflammation and symptoms in occupations at risk of asthma is still not fully understood. We aimed to study the evolution during apprenticeship of inflammation markers, bronchial hyperresponsiveness (BHR) and symptoms in at-risk subgroups as defined from measurements of markers made shortly after the start of training. METHODS: Respiratory symptoms, FEV1 and airway resistance post-bronchial challenge (MBC) test results, fractional exhaled nitric oxide (FeNO) measurements, and eosinophils in nasal lavage fluid were investigated in apprentice bakers, pastry-makers and hairdressers. Four visits were conducted: at the start of the training and every six months thereafter. Four baseline risk groups were defined, based on, (i) a high level of FeNO (NO), (ii) eosinophils > 1% (Eosino), (iii) a ≥ 15% decrease in FEV1 during the MBC test (HR), and (iv) a ≥ 50% increase in the resistance (Resist). The statistical analysis relied on mixed models. RESULTS: At baseline, the inflammation markers were related to the MBC markers. There was no evidence to suggest that the baseline risk groups predict a differential evolution of the airway inflammation and bronchial responsiveness markers, or the asthma-like symptoms considered. The baseline risk groups defined from MBC test predicted the levels of MBC markers. Similarly, the baseline risk groups based on eosinophilic inflammation predicted the levels of markers for eosinophilia. These results were similar in the three training tracks, with the exception of the FeNO levels which were not different according to the Eosino risk group. Twelve possible new asthma cases were identified, only the HR risk group predicted their occurrence. CONCLUSIONS: Among this young population, at-risk groups based on initial high levels of inflammation markers did not experience any worsening during the follow-up. However, initial BHR predicted consistently high levels of all markers considered and occurrence of possible asthma.


Assuntos
Asma/diagnóstico , Biomarcadores/análise , Hiper-Reatividade Brônquica/fisiopatologia , Inflamação/fisiopatologia , Doenças Profissionais/diagnóstico , Adolescente , Testes de Provocação Brônquica , Eosinófilos/metabolismo , Feminino , França , Humanos , Estudos Longitudinais , Masculino , Líquido da Lavagem Nasal/citologia , Óxido Nítrico/análise , Análise de Regressão , Testes Cutâneos , Adulto Jovem
8.
BMC Public Health ; 16(1): 1164, 2016 11 16.
Artigo em Inglês | MEDLINE | ID: mdl-27852249

RESUMO

BACKGROUND: There are still uncertainties regarding the respective prevalence, diagnosis and management of occupational asthma (OA) and work-exacerbated asthma (WEA). There is as yet no standardized methodology to differentiate their diagnosis. A proper management of both OA and WEA requires tools for a good phenotyping in terms of control, severity and quality of life in order to propose case-specific therapeutical and preventive measures. Moreover, there is a lack of knowledge concerning their actual costs. METHODS: This project aims at comparing 3 groups of asthmatic subjects at work: subjects with OA, with WEA, and with non-work-related asthma (NWRA) in terms of control, severity and quality of life on the one hand, and estimating the prevalence of OA, WEA and NWRA in active workers and the economic costs of OA and WEA, on the other hand. Control will be assessed using the Asthma Control Test questionnaire and the daily Peak Exploratory Flow variability, severity from the treatment level, and quality of life using the Asthma Quality of Life Questionnaire. A first step will be to apply a standardized diagnosis procedure of WEA and OA. This study includes an epidemiological part in occupational health services by volunteering occupational physicians, and a clinical case-study based on potentially asthmatic subjects referred to ten participating University Hospital Occupational Diseases Departments (UHODD) because of a suspected WRA. The subjects' characterization with respect to OA and WEA is organized in three steps. In Step 1 (epidemiological part), occupational physicians screen for potentially actively asthmatics through a questionnaire given to workers seen in mandatory medical visit. In step 2 (both parts), the subjects with a suspicion of work-related respiratory symptoms answer a detailed questionnaire and perform a two-week OASYS protocol enabling us, using a specifically developed algorithm, to classify them into probably NWRA, suspected OA, suspected WEA. The two latter groups are referred to UHODD for a final harmonized diagnosis (step 3). Finally, direct and indirect disease-related costs during the year preceding the diagnosis will be explored among WRA cases, as well as these costs and the intangible costs, during the year following the diagnosis. DISCUSSION: This project is an attempt to obtain a global picture of occupational asthma in France thanks to a multidisciplinary approach.


Assuntos
Asma Ocupacional/epidemiologia , Asma/epidemiologia , Efeitos Psicossociais da Doença , Custos de Cuidados de Saúde/estatística & dados numéricos , Adulto , Asma/economia , Asma/etiologia , Asma Ocupacional/economia , Protocolos Clínicos , Progressão da Doença , Feminino , França/epidemiologia , Humanos , Masculino , Prevalência , Qualidade de Vida , Inquéritos e Questionários , Adulto Jovem
9.
Oecologia ; 182(4): 1053-1062, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27646717

RESUMO

Urban habitats are described as having an overall negative influence on many fitness-related traits in several bird species, but a vital function such as immunity remains poorly studied. The immune response is strongly linked to individual condition, which partly depends on resource availability and the parasitic context that often differ between urban and natural habitats. A difference between the immunity of populations dwelling in urban areas and populations from more natural habitats can, therefore, be hypothesized. We conducted a 2-year experimental study on great tits (Parus major) in urban and forest areas. We stimulated the constitutive immunity of nestlings and assessed both the inflammatory response by measuring the plasma levels of haptoglobin, an inflammatory marker, and its activation cost through the loss of body mass. In addition, we checked the nestlings for ectoparasites and assessed haemosporidian prevalence in adults. Nestlings from urban sites produced relatively less haptoglobin and lost more body mass than those from forest sites, which suggests that the activation of constitutive immunity is more costly for birds living in urban sites than for those living in the forest. We detected no ectoparasite in birds in both habitats. However, urban adults showed lower haemosporidian prevalence than forest ones, suggesting a reduced exposure to these parasites and their vectors in towns. Overall, our study provides evidence for an immune difference between urban and forest populations. Because immunity is crucial for organism fitness, it is of prime interest to identify causes and processes at the origin of this difference.


Assuntos
Imunidade , Passeriformes/imunologia , Animais , Ecossistema , Meio Ambiente , Parasitos
10.
ACS Appl Mater Interfaces ; 7(36): 19906-13, 2015 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-26315344

RESUMO

In ferroelectric thin films, controlling the orientation of the polarization is a key element to controlling their physical properties. We use laboratory and synchrotron X-ray diffraction to investigate ferroelectric bicolor PbTiO3/PbZr0.2Ti0.8O3 and tricolor PbTiO3/SrTiO3/PbZr0.2Ti0.8O3 superlattices and to study the role of the SrTiO3 layers on the domain structure. In the tricolor superlattices, we demonstrate the existence of 180° ferroelectric stripe nanodomains, induced by the depolarization field produced by the SrTiO3 layers. Each ultrathin SrTiO3 layer modifies the electrostatic boundary conditions between the ferroelectric layers compared to the corresponding bicolor structures, leading to the suppression of the a/c polydomain states. Combined with the electrostatic effect, the tensile strain induced by PbZr0.2Ti0.8O3 in the PbTiO3 layers leads to polarization rotation in the system as evidenced by grazing incidence X-ray measurements. This polarization rotation is associated with the monoclinic Mc phase as revealed by the splitting of the (HHL) and (H0L) reciprocal lattice points. This work demonstrates that the tricolor paraelectric/ferroelectric superlattices constitute a tunable system to investigate the concomitant effects of strains and depolarizing fields. Our studies provide a pathway to stabilize a monoclinic symmetry in ferroelectric layers, which is of particular interest for the enhancement of the piezoelectric properties.

11.
Ann Occup Hyg ; 59(4): 504-13, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25535181

RESUMO

A set of 270 bioaerosol samples was taken from 15 composting facilities using polystyrene closed-face filter cassettes (CFCs). The objective was to measure the quantity of endotoxin deposits on the inner surfaces of the cassettes (sometimes referred to as 'wall deposits'). The results show that endotoxins are deposited on the inner surfaces of the CFCs through sampling and/or handling of samples. The quantity of endotoxins measured on inner surfaces range between 0.05 (the limit of detection of the method) and 3100 endotoxin units per cassette. The deposits can represent a large and variable percentage of the endotoxins sampled. More than a third of the samples presented a percentage of inner surface deposits >40% of the total quantity of endotoxins collected (filter + inner surfaces). Omitting these inner surface deposits in the analytical process lead to measurement errors relative to sampling all particles entering the CFC sampler, corresponding to a developing consensus on matching the inhalable particulate sampling convention. The result would be underestimated exposures and could affect the decision as to whether or not a result is acceptable in comparison to airborne concentration limits defined in terms of the inhalability convention. The results of this study suggest including the endotoxins deposited on the inner surfaces of CFCs during analysis. Further researches are necessary to investigate endotoxin deposits on the inner cassette surfaces in other working sectors.


Assuntos
Aerossóis/análise , Endotoxinas/análise , Monitoramento Ambiental/instrumentação , Instalações de Eliminação de Resíduos , Poluentes Ocupacionais do Ar/análise , Monitoramento Ambiental/métodos , Filtração , Exposição Ocupacional/análise , Manejo de Espécimes
12.
Chest ; 142(1): 192-199, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22281800

RESUMO

BACKGROUND: There is no consensus at the present time about the effect of welding on lung function decline. This study compared lung function decline between blue-collar workers exposed and not exposed to welding fumes in a French longitudinal cohort of 21,238 subjects aged 37 to 52 years at inclusion. METHODS: Medical data, occupation, sector of activity, and spirometry were recorded twice by occupational physicians in 1990 and 1995. A job-exposure matrix was used to identify 503 male blue-collar workers exposed to welding fumes and 709 control subjects and to define the weekly duration of exposure to welding fumes. RESULTS: Baseline lung function parameters were higher in workers exposed to welding fumes than in control subjects. After a 5-year follow-up, welding-fume exposure was associated with a nonsignificant decline in FVC (P = .06) and FEV(1) (P = .07) after adjustment for age, pack-years, BMI, and baseline value of the parameter. A significant accelerated decline in FEV(1) (P = .046) was also observed in never smokers exposed to welding fumes. An "exposure-response" relationship was observed between FEV(1) decline and weekly duration of exposure to welding fumes in nonsmokers but not in smokers. CONCLUSIONS: Blue-collar workers exposed to welding fumes showed accelerated decline in lung function, which, in nonsmokers, was related to weekly duration of exposure.


Assuntos
Poluentes Ocupacionais do Ar/efeitos adversos , Pulmão/fisiopatologia , Soldagem , Adulto , Poluentes Ocupacionais do Ar/farmacologia , Estudos de Casos e Controles , Estudos de Coortes , Volume Expiratório Forçado/fisiologia , França , Humanos , Estudos Longitudinais , Pulmão/efeitos dos fármacos , Masculino , Pessoa de Meia-Idade , Espirometria
13.
BMC Pulm Med ; 10: 37, 2010 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-20604945

RESUMO

BACKGROUND: Bronchial Hyperresponsiveness (BHR) is considered a hallmark of asthma. Other methods are helpful in epidemiological respiratory health studies including Fractional Exhaled Nitric Oxide (FENO) and Eosinophils Percentage (EP) in nasal lavage fluid measuring markers for airway inflammation along with the Forced Oscillatory Technique measuring Airway resistance (AR). Can their outcomes discriminate profiles of respiratory health in healthy subjects starting apprenticeship in occupations with a risk of asthma? METHODS: Rhinoconjunctivitis, asthma-like symptoms, FEV1 and AR post-Methacholine Bronchial Challenge (MBC) test results, FENO measurements and EP were all investigated in apprentice bakers, pastry-makers and hairdressers not suffering from asthma. Multiple Correspondence Analysis (MCA) was simultaneously conducted in relation to these groups and this generated a synthetic partition (EI). Associations between groups of subjects based on BHR and EI respectively, as well as risk factors, symptoms and investigations were also assessed. RESULTS: Among the 441 apprentice subjects, 45 (10%) declared rhinoconjunctivitis-like symptoms, 18 (4%) declared asthma-like symptoms and 26 (6%) suffered from BHR. The mean increase in AR post-MBC test was 21% (sd = 20.8%). The median of FENO values was 12.6 ppb (2.6-132 range). Twenty-six subjects (6.7%) had EP exceeding 14%. BHR was associated with atopy (p < 0.01) and highest FENO values (p = 0.09). EI identified 39 subjects with eosinophilic inflammation (highest values of FENO and eosinophils), which was associated with BHR and atopy. CONCLUSIONS: Are any of the identified markers predictive of increased inflammatory responsiveness or of development of symptoms caused by occupational exposures? Analysis of population follow-up will attempt to answer this question.


Assuntos
Asma/epidemiologia , Hiper-Reatividade Brônquica/diagnóstico , Hiper-Reatividade Brônquica/epidemiologia , Doenças Profissionais/diagnóstico , Doenças Profissionais/epidemiologia , Adolescente , Biomarcadores , Conjuntivite/diagnóstico , Conjuntivite/epidemiologia , Culinária/estatística & dados numéricos , Feminino , Humanos , Masculino , Valor Preditivo dos Testes , Prevalência , Rinite/diagnóstico , Rinite/epidemiologia , Fatores de Risco , Estudantes/estatística & dados numéricos , Inquéritos e Questionários
14.
Am J Respir Crit Care Med ; 182(6): 738-44, 2010 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-20508219

RESUMO

RATIONALE: Airway inflammation is a hallmark of asthma. Several studies have validated the use of the fractional concentration of exhaled nitric oxide (Fe(NO)) as a surrogate marker of airway inflammation in asthma. OBJECTIVES: We examined how the change in Fe(NO) levels, since the beginning of occupational exposure, could be associated with the incidence of bronchial hyperresponsiveness (BHR) among baker, pastry maker, and hairdresser apprentices during their 2-year training. METHODS: A standardized questionnaire was administered; skin prick tests for common and specific occupational allergens were done; methacholine challenge and measurement of Fe(NO) were performed 6, 12, and 15 months after the first examination. MEASUREMENTS AND MAIN RESULTS: Of 441 apprentices initially included, 351 completed the study. The increase in Fe(NO), since the beginning of exposure, was associated with the incidence of BHR (odds ratio, 2.00 [95% confidence interval, 1.21-3.32] per unit increase in log parts per billion) both in atopic and nonatopic subjects. The average increase in Fe(NO) was similar in atopic and nonatopic subjects and was unrelated to past or current smoking habits, sex, or training track. Atopy in bakers/pastry makers and sensitization to alkaline persulfates in hairdressers were also independently associated with the incidence of BHR. BHR occurred sooner among bakers/pastry makers than among hairdressers, but its incidence leveled off later. CONCLUSIONS: Our results suggest that measurement of Fe(NO), a simple and reproducible test, could be useful in the screening of BHR in workers newly exposed to agents known to cause occupational asthma.


Assuntos
Indústria da Beleza , Hiper-Reatividade Brônquica/diagnóstico , Indústria de Processamento de Alimentos , Óxido Nítrico/metabolismo , Doenças Profissionais/diagnóstico , Exposição Ocupacional/efeitos adversos , Adolescente , Asma/fisiopatologia , Biomarcadores/sangue , Testes Respiratórios/métodos , Hiper-Reatividade Brônquica/epidemiologia , Broncoconstritores , Expiração , Feminino , Seguimentos , Humanos , Incidência , Inflamação/etiologia , Exposição por Inalação/efeitos adversos , Masculino , Cloreto de Metacolina , Óxido Nítrico/análise , Doenças Profissionais/epidemiologia , Inquéritos e Questionários
15.
J Colloid Interface Sci ; 341(2): 201-8, 2010 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-19875127

RESUMO

Water-in-oil (W/O) microemulsion is a well-suitable confined reacting medium for the synthesis of structured functional nanoparticles of controlled size and shape. During the last decade, it allowed the synthesis of multi-functional silica nanoparticles with morphologies as various as core-shell, homogenous dispersion or both together. The morphology and properties of the different intermediates and final materials obtained through this route are discussed in the light of UV-Vis-NIR spectroscopy, dynamic light scattering (DLS) and X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM) and magnetometer SQUID analysis.


Assuntos
Emulsões/química , Nanopartículas/química , Óleos/química , Dióxido de Silício/química , Água/química , Amônia/química , Cério/química , Compostos Férricos/química , Vidro/química , Dureza , Heptanos/química , Concentração de Íons de Hidrogênio , Luz , Magnetismo , Microscopia Eletrônica , Microscopia de Fluorescência , Tamanho da Partícula , Polidocanol , Polietilenoglicóis/química , Espalhamento de Radiação , Silanos/química , Espectrofotometria Ultravioleta , Propriedades de Superfície , Tensoativos/química , Temperatura , Difração de Raios X , Óxido de Zinco/química
16.
BMC Public Health ; 9: 113, 2009 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-19389222

RESUMO

BACKGROUND: Occupational asthma is a common type of asthma caused by a specific agent in the workplace. The basic alteration of occupational asthma is airways inflammation. Although most patients with occupational asthma are mature adults, there is evidence that airways inflammation starts soon after inception of exposure, including during apprenticeship. Airways hyper responsiveness to methacholine is a valid surrogate marker of airways inflammation, which has proved useful in occupational epidemiology. But it is time-consuming, requires active subject's cooperation and is not readily feasible. Other non-invasive and potentially more useful tests include the forced oscillation technique, measurement of fraction exhaled nitric oxide, and eosinophils count in nasal lavage fluid. METHODS AND DESIGN: This study aims to investigate early development of airways inflammation and asthma-like symptoms in apprentice bakers, pastry-makers and hairdressers, three populations at risk of occupational asthma whose work-related exposures involve agents of different nature. The objectives are to (i) examine the performance of the non-invasive tests cited above in detecting early airways inflammation that might eventually develop into occupational asthma; and (ii) evaluate whether, and how, constitutional (e.g. atopy) and behavioural (e.g. smoking) risk factors for occupational asthma modulate the effects of allergenic and/or irritative substances involved in these occupations. This paper presents the study rationale and detailed protocol. DISCUSSION: Among 441 volunteers included at the first visit, 354 attended the fourth one. Drop outs were investigated and showed unrelated to the study outcome. Sample size and follow-up participation rates suggest that the data collected in this study will allow it to meet its objectives.


Assuntos
Poluentes Ocupacionais do Ar/intoxicação , Asma/imunologia , Indústria da Beleza , Indústria de Processamento de Alimentos , Mediadores da Inflamação/imunologia , Doenças Profissionais/imunologia , Exposição Ocupacional/efeitos adversos , Adolescente , Poluentes Ocupacionais do Ar/imunologia , Asma/diagnóstico , Asma/etiologia , Feminino , Seguimentos , Humanos , Inflamação/etiologia , Inflamação/imunologia , Exposição por Inalação/efeitos adversos , Masculino , Líquido da Lavagem Nasal/citologia , Líquido da Lavagem Nasal/imunologia , Doenças Profissionais/etiologia , Testes de Função Respiratória , Sistema Respiratório/efeitos dos fármacos , Sistema Respiratório/imunologia , Fatores de Risco , Testes Cutâneos , Fumar
17.
BMC Pulm Med ; 9: 53, 2009 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-20043846

RESUMO

BACKGROUND: Airway inflammation and airway hyperresponsiveness (AHR) are two characteristic features of asthma. Fractional exhaled nitric oxide (FENO) has shown good correlation with AHR in asthmatics. Less information is available about FENO as a marker of inflammation from work exposures. We thus examined the relation between FENO and AHR in lifeguards undergoing exposure to chloramines in indoor pools. METHODS: 39 lifeguards at six indoor pools were given a respiratory health questionnaire, FENO measurements, spirometry, and a methacholine bronchial challenge (MBC) test. Subjects were labeled MBC+ if the forced expiratory volume (FEV1) fell by 20% or more. The normalized linear dose-response slope (NDRS) was calculated as the percentage fall in FEV1 at the last dose divided by the total dose given. The relation between MBC and FENO was assessed using logistic regression adjusting on confounding factors. The association between NDRS and log-transformed values of FENO was tested in a multiple linear regression model. RESULTS: The prevalence of lifeguards MBC+ was 37.5%. In reactors, the median FENO was 18.9 ppb (90% of the predicted value) vs. 12.5 ppb (73% predicted) in non-reactors. FENO values >or= 60% of predicted values were 80% sensitive and 42% specific to identify subjects MBC+. In the logistic regression model no other factor had an effect on MBC after adjusting for FENO. In the linear regression model, NDRS was significantly predicted by log FENO. CONCLUSIONS: In lifeguards working in indoor swimming pools, elevated FENO levels are associated with increased airway responsiveness.


Assuntos
Asma/diagnóstico , Asma/metabolismo , Óxido Nítrico/metabolismo , Saúde Ocupacional , Hipersensibilidade Respiratória/diagnóstico , Hipersensibilidade Respiratória/metabolismo , Natação/fisiologia , Adulto , Asma/fisiopatologia , Testes de Provocação Brônquica , Estudos Transversais , Estudos de Viabilidade , Feminino , Volume Expiratório Forçado/fisiologia , Humanos , Modelos Lineares , Masculino , Cloreto de Metacolina , Valor Preditivo dos Testes , Hipersensibilidade Respiratória/fisiopatologia , Sensibilidade e Especificidade , Espirometria
19.
Bull Cancer ; 90(4): 363-70, 2003 Apr.
Artigo em Francês | MEDLINE | ID: mdl-12801820

RESUMO

Oncolor, the French regional cancer network of Lorraine, proposes clinical guidelines for the diagnosis, the treatment and the follow-up of cancers. In addition to paper documents, two computerized supports, a web site and the Kasimir software have been developed to make the use of these guidelines and their updating easier. This study aims at evaluating these three tools in breast and prostate cancer and to determine if computerized supports provide an additional help and an added value. From May to July 2001, 25 physicians of the Oncolor network have analysed, by consulting the guidelines on each of the 3 supports, 23 clinical cases of breast cancer and 22 cases of prostate cancer, i.e. in total 1,293 cases. We observe for breast cancer a response rate consistent with the guideline significantly higher with the Kasimir software compared to paper (87.1% versus 77.8%) or to Internet (87.1% versus 75.8%), an optimisation of the recourse to a specialised physician or a pluridisciplinary committee and globally a good satisfaction of the users. These results induce us to continue with the Kasimir experiment, to develop it for other cancers, especially those with a complex management and to evaluate its impact on medical practices.


Assuntos
Neoplasias da Mama/terapia , Sistemas de Apoio a Decisões Clínicas/normas , Guias de Prática Clínica como Assunto , Neoplasias da Próstata/terapia , Feminino , França , Fidelidade a Diretrizes , Pesquisas sobre Atenção à Saúde , Humanos , Masculino
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