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1.
J Environ Radioact ; 255: 107030, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36191507

RESUMO

137Cs and 241Pu (via 241Am) concentrations were measured γ-spectrometrically on air filters from the early 1960s (mainly from 1964-66) from Vienna, Austria, and an alpine station in Salzburg, Austria. Accelerator mass spectrometry (AMS) was used to determine 240Pu/239Pu, 236U/238U and 233U/236U atom ratios as well as 236U, 239Pu and 240Pu atom concentrations. The maximum 236U/238U atom ratio of these unique undisturbed global fallout samples was (1.19 ± 0.31) × 10-5 in spring 1964. The 233U/236U atom ratios were found within (0.15-0.49) × 10-2 and indicate that the weapons tests of the early 1960s can be excluded as 233U source. The 236U/239Pu atom ratios were calculated in the range of 0.22-0.48.


Assuntos
Filtros de Ar , Plutônio , Monitoramento de Radiação , Cinza Radioativa , Urânio , Monitoramento de Radiação/métodos , Áustria , Estudos Retrospectivos , Plutônio/análise , Cinza Radioativa/análise , Urânio/análise
2.
Clin Otolaryngol ; 45(3): 394-401, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32058675

RESUMO

OBJECTIVES: To evaluate the clinical efficacy of a high-efficiency air purifier in patients with allergic rhinitis. DESIGN: We conducted a randomised, double-blind, clinical controlled trial with active and inactive versions of an air purifier. Our study included patients with allergic rhinitis who were sensitive to Artemisia pollen and treatment of the indoor environment using air filtration at night. We evaluated the clinical efficacy of indoor air filtration during the Artemisia pollen scattering season in Yulin City in Shanxi Province, China. SETTING: The First Hospital of Yulin (Yulin City, Shanxi Province, China). PARTICIPANTS: A total of 90 patients with allergic rhinitis who were sensitive to allergens of Artemisia pollen were randomly assigned to one of two groups in equal numbers. MAIN OUTCOME MEASURES: The primary outcome measure was the difference in visual analogue scale scores from baseline. Secondary outcomes were changes from baseline in nasal symptoms, allergy symptom scores, responses to the Rhinoconjunctivitis Quality of Life Questionnaire, Epworth Sleepiness Scale scores and tolerability scores for the air purifier. RESULTS: Based on the allergy symptom score, we found significant differences in rhinitis symptoms between the groups who used the active versus the inactive air purifier. CONCLUSIONS: The results of our investigation demonstrated the health benefits of particle filtration.


Assuntos
Filtros de Ar , Artemisia , Pólen/efeitos adversos , Rinite Alérgica/etiologia , Rinite Alérgica/terapia , Adulto , Poluição do Ar em Ambientes Fechados , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Rinite Alérgica/diagnóstico , Resultado do Tratamento
3.
Allergol Immunopathol (Madr) ; 48(6): 745-752, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31879043

RESUMO

Asthma and other inhaled allergies are some of the most common paediatric diseases. The association of exposure to allergens with induction and exacerbation of symptoms has been proven. The majority of allergens are permanently or periodically suspended in the air, which leads to impaired quality of life for sensitive patients. Therefore, many methods of prevention and therapy of allergic diseases have been developed. The method of allergen exposure avoidance is often the first and the most significant measure. The present research has been conducted to evaluate, based on scientific data, which measures have the most reliable evidence of effectiveness. Environmental allergen avoidance methods, despite limited evidence supporting their clinical efficacy, are listed as the main therapeutic approaches in most recommendations. The significance of the holistic approach is also emphasised: only simultaneous introduction of several avoidance methods can bring possibly beneficial effects for the patient.


Assuntos
Poluição do Ar em Ambientes Fechados/prevenção & controle , Alérgenos/efeitos adversos , Asma/prevenção & controle , Saúde Holística , Exposição por Inalação/prevenção & controle , Filtros de Ar , Poluição do Ar em Ambientes Fechados/efeitos adversos , Alérgenos/imunologia , Animais , Asma/imunologia , Roupas de Cama, Mesa e Banho , Baratas/imunologia , Dermatophagoides farinae/imunologia , Fungos/imunologia , Humanos , Umidade , Exposição por Inalação/efeitos adversos , Camundongos/imunologia , Animais de Estimação/imunologia , Pólen/imunologia , Qualidade de Vida
4.
Curr Res Transl Med ; 68(1): 23-28, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31787568

RESUMO

PURPOSE OF THE STUDY: Invasive aspergillosis (IA) is the most prevalent invasive fungal disease (IFD) in neutropenic patients. Environment is the main source of Aspergillus spores aerosolization especially during building construction. International guidelines recommend mechanical protection during hospital building works; otherwise the use of antifungal prophylaxis is not clearly indicated. Our objective was to determine the efficacy of antifungal prophylaxis by posaconazole on IA incidence in acute myeloid leukemia population and to analyse the benefit of this prophylaxis and HEPA-filters during hospital buildings works. PATIENTS AND METHODS: We included patients treated for acute myeloid leukemia at Brest teaching hospital from January 2009 to December 2015. We compared incidence of IA in the group treated by posaconazole from 2012 to 2015 to the incidence of IA in the first group who did not receive antifungal prophylaxis (from 2009 to 2011). The one-year overall survival was also analyzed using the Kaplan-Meier method. RESULTS: 245 patients were enrolled including 151 treated with posaconazole. 23 IA were diagnosed between 2009 and 2011 (without antifungal prophylaxis), then 31 between 2012 and 2015 (with posaconazole) without statistical difference between the incidence densities (0.34 per 100 hospitalization-days vs. 0.30 per 100 hospitalization-days, p = 0.71). Incidence density of IA increased during building works (2.40 per 100 hospitalization-days vs. 0.28 per 100 hospitalization-days, p < 0.0001). The incidence density of IA significantly decreased during construction periods when posaconazole prophylaxis was used (1.59 per 100 hospitalization-days vs. 4.87 per 100 hospitalization-days p < 0.0001). CONCLUSION: Our study suggests, for the first time, the interest of antifungal prophylaxis in addition to HEPA filtration in prevention of IA during hospital building works.


Assuntos
Antifúngicos/uso terapêutico , Aspergilose/prevenção & controle , Infecções Fúngicas Invasivas/prevenção & controle , Leucemia Mieloide Aguda/complicações , Triazóis/uso terapêutico , Adulto , Aerossóis , Filtros de Ar , Microbiologia do Ar , Poluição do Ar em Ambientes Fechados , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Aspergilose/epidemiologia , Aspergillus/efeitos dos fármacos , Aspergillus/isolamento & purificação , Aspergillus/fisiologia , Terapia Combinada , Exposição Ambiental , Neutropenia Febril/complicações , Feminino , Filtração , França , Transplante de Células-Tronco Hematopoéticas , Arquitetura Hospitalar , Hospitais de Ensino , Humanos , Incidência , Infecções Fúngicas Invasivas/epidemiologia , Estimativa de Kaplan-Meier , Leucemia Mieloide Aguda/mortalidade , Leucemia Mieloide Aguda/terapia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Estudos Retrospectivos , Esporos Fúngicos
5.
Sci Total Environ ; 671: 59-65, 2019 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-30927728

RESUMO

Exposure to viable bacterial and fungal spores re-aerosolized from air handling filters may create a major health risk. Assessing and controlling this exposure have been of interest to the bio-defense and indoor air quality communities. Methods are being developed for inactivating stress-resistant viable microorganisms collected on ventilation filters. Here we investigated the inactivation of spores of Bacillus thuringiensis var. kurstaki (Btk), a recognized simulant for B. antracis, and Aspergillus fumigatus, a common opportunistic pathogen used as an indicator for indoor air quality. The viability change was measured on filters treated with ultraviolet (UV) irradiation and gaseous iodine. The spores were collected on high-efficiency particulate air (HEPA) and non-HEPA filters, both flattened for testing purposes to represent "surface" filters. A mixed cellulose ester (MCE) membrane filter was also tested as a reference. Additionally, a commercial HEPA unit with a deep-bed (non-flattened) filter was tested. Combined treatments of Btk spores with UV and iodine on MCE filter produced a synergistic inactivation effect. No similar synergy was observed for A. fumigatus. For spores collected on an MCE filter, the inactivation effect was about an order of magnitude greater for Btk compared to A. fumigatus. The filter type was found to be an important factor affecting the inactivation of Btk spores while it was not as influential for A. fumigatus. Overall, the combined effect of UV irradiation and gaseous iodine on viable bacterial and fungal spores collected on flat filters was found to be potent. The benefit of either simultaneous or sequential treatment was much lower for Btk spores embedded inside the deep-bed (non-flattened) HEPA filter, but for A. fumigatus the inactivation on flattened and non-flattened HEPA filters was comparable. For both species, applying UV first and gaseous iodine second produced significantly higher inactivation than when applying them simultaneously or in an opposite sequence.


Assuntos
Filtros de Ar/microbiologia , Poluição do Ar em Ambientes Fechados/análise , Desinfecção/métodos , Iodo/administração & dosagem , Esporos Bacterianos/efeitos dos fármacos , Esporos Fúngicos/efeitos dos fármacos , Raios Ultravioleta , Aspergillus fumigatus/efeitos dos fármacos , Aspergillus fumigatus/fisiologia , Bacillus thuringiensis/efeitos dos fármacos , Bacillus thuringiensis/fisiologia , Gases/administração & dosagem , Esporos Bacterianos/fisiologia , Esporos Fúngicos/fisiologia
6.
BMC Public Health ; 18(1): 841, 2018 07 06.
Artigo em Inglês | MEDLINE | ID: mdl-29976165

RESUMO

BACKGROUND: Allergic rhinitis (AR) is a worldwide health problem. Allergen avoidance is strongly recommended for AR patients. Air purification can reduce concentrations of particles in indoor air, including those of allergens. Air purifiers have been recommended by clinicians for AR patients, but few studies have focused on the removal of airborne allergens from home environments. Such studies have been limited by a lack of blinding, small samples, or a failure to measure allergen levels, disease activity, or a combination of these factors. This study investigates the efficacy of a high-efficiency air purifier in reducing disease activity in the homes of AR patients sensitive to the allergens produced by Artemisia (mugwort) pollen. METHODS: This is a randomized, double-blind, clinical controlled trial that will test active and inactive versions of an air purifier (Atmosphere®; Amway China). Sixty AR patients sensitive to the allergens produced by Artemisia pollen will be assigned randomly to two groups of equal numbers. All patients will undergo a 4-week treatment period and a 4-week observation period. Evaluation will be conducted at baseline (day 0) and on days 7, 14, 21, 28, and 56. The primary outcome measure will be the difference in visual analog scale scores from baseline. Secondary outcomes will be changes from baseline in nasal symptoms, allergy symptom scores, responses to the Rhinoconjunctivitis Quality of Life Questionnaire, Epworth Sleepiness Scale scores, and tolerability scores for the air purifier. Side effects of treatment will be recorded. DISCUSSION: Reducing exposure to allergens can reduce the risk of conditions such as AR. We hypothesise that AR patients sensitive to the allergens produced by Artemisia pollen will not suffer symptoms in a pollen-free environment. AR patients can remove pollen from their homes using air purifiers, decreasing the risk of symptoms. We expect that our study results will provide reliable evidence for determining the effects of air-purification therapy. TRIAL REGISTRATION: ChiCTR-INR-17012481 . (Retrospectively registered 26 August 2017).


Assuntos
Filtros de Ar , Poluição do Ar em Ambientes Fechados/prevenção & controle , Alérgenos/efeitos adversos , Artemisia/efeitos adversos , Pólen/efeitos adversos , Rinite Alérgica/prevenção & controle , Alérgenos/análise , China , Protocolos Clínicos , Método Duplo-Cego , Humanos , Rinite Alérgica/etiologia
7.
Environ Pollut ; 239: 777-787, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29729619

RESUMO

In this work, both PM10 filters and leaves have been collected, on a daily basis, over a period of five months and compared systematically. Filters were taken from an air-quality monitoring station and leaves from two Tilia cordata trees, both located near the railway station of Parma. SEM-EDS analysis on the surface and across the leaves shows that magnetic particles are almost entirely made of magnetite, and that they are found invariably on the leaves surface. The saturation isothermal magnetic remanence (SIRM) shows that for both filters and leaves the magnetic fraction mainly consists of a low coercivity, magnetite-like phase. The magnetic signals of filter and leaves and atmospheric PM concentrations are compared. The correlation is better for filters, mostly with parameters related to vehicular pollution, and improved for both filters and leaves once data were averaged on a 10 days basis. Filters and leaves equally show an increase in magnetic signal during the fall-winter period together with PM10 content. The comparison between leaves and filters shows that: 1) leaves give a qualitative picture, and in our case they could be used as environmental proxies after averaging the results over multiple days; 2) the correlation with PM10 is weaker, indicating that there is a PM10 contribution from non-magnetic particles, like calcite and clay minerals, pollen and spores; 3) multidomain particles contribution from filters indicates a strong relation with vehicular polluters, suggesting the important role of larger particles; 4) magnetization from leaves and filters are weakly related, due to the different sampling lapse.


Assuntos
Poluentes Atmosféricos/análise , Monitoramento Ambiental/métodos , Material Particulado/análise , Folhas de Planta/química , Tilia/química , Filtros de Ar , Poluição do Ar/análise , Animais , Cidades , Monitoramento Ambiental/instrumentação , Itália , Magnetismo , Estações do Ano
8.
Health Phys ; 114(5): 479-485, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29505432

RESUMO

Dust loading on air sample filters is known to cause a loss of efficiency for direct counting of alpha activity on the filters, but the amount of dust loading and the correction factor needed to account for attenuated alpha particles is difficult to assess. In this paper, correction factors are developed by statistical analysis of a large database of air sample results for a uranium and plutonium processing facility at the Savannah River Site. As is typically the case, dust-loading data is not directly available, but sample volume is found to be a reasonable proxy measure; the amount of dust loading is inferred by a combination of the derived correction factors and a Monte Carlo model. The technique compares the distribution of activity ratios [beta/(beta + alpha)] by volume and applies a range of correction factors on the raw alpha count rate. The best-fit results with this method are compared with MCNP modeling of activity uniformly deposited in the dust and analytical laboratory results of digested filters. A linear fit is proposed to evenly-deposited alpha activity collected on filters with dust loading over a range of about 2 mg cm to 1,000 mg cm.


Assuntos
Contaminação Radioativa do Ar/análise , Partículas alfa , Poeira/análise , Monitoramento Ambiental/instrumentação , Filtração/instrumentação , Monitoramento de Radiação/instrumentação , Filtros de Ar , Plutônio/análise , Urânio/análise
9.
Artigo em Coreano | WPRIM | ID: wpr-766469

RESUMO

Particulate matter is an air pollutant emitted from both natural and anthropogenic sources, and its adverse health effects have been well documented in time-series analyses and cohort studies. The effect size of particulate matter exposure—a roughly 0.5% increase in mortality for each 10 µg/m³ increment of short-term exposure to particulate matter with aerodynamic diameter ≤10 µm and approximately a 10% increase for each 10 µg/m³ increment of long-term exposure to particulate matter with aerodynamic diameter ≤2.5 µm—is small compared to other risk factors, but the exposure is involuntary and affects the entire population, which makes particulate matter pollution an important public health issue. The World Health Organization and Korean government have both established guidelines for particulate matter concentrations, but the Korean guideline is less stringent than that of the World Health Organization. The annual mean concentration of particulate matter in Korea is decreasing, but the trend seems to be slowing. In addition to policy efforts to reduce particulate matter emission, personal approaches such as the use of face masks and air purifiers have been recommended. Personal approaches may not solve the fundamental problem, but can provide temporary mitigation until efforts to reduce emission make progress.


Assuntos
Humanos , Filtros de Ar , Estudos de Coortes , Medicina Ambiental , Epidemiologia , Coreia (Geográfico) , Máscaras , Mortalidade , Material Particulado , Saúde Pública , Fatores de Risco , Organização Mundial da Saúde
10.
Adv Exp Med Biol ; 955: 9-18, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28000141

RESUMO

This study evaluates the mass concentration and chemical composition of particulate matter (PM), collected in the chamber complex of the underground health resort located in the Wieliczka Salt Mine in southern Poland. Physical and chemical properties of PM were examined from the standpoint of their possible connection with therapeutic effects of the subterranean air in the mine. We found that in three underground spots we measured the average concentration of PM did not exceed 30 µg/m3. Chemical composition of PM was dominated by sodium chloride, making up 88 % of its mass, on average. It was shown that the underground ambient concentration of PM and its chemical composition depended mostly on the nature of the rock material present in the ventilation tunnel of the health resort, filtering the incoming air. The presence and effect of external sources of PM, including patients' activity, also had an impact on the underground PM concentration.


Assuntos
Ar Condicionado , Poluição do Ar em Ambientes Fechados , Estâncias para Tratamento de Saúde , Mineração , Material Particulado/análise , Cloreto de Sódio/análise , Espeleoterapia/métodos , Ar Condicionado/instrumentação , Filtros de Ar , Monitoramento Ambiental/métodos , Humanos , Polônia
11.
Pest Manag Sci ; 73(6): 1134-1142, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27607021

RESUMO

BACKGROUND: The pneumatic precision drills used in maize sowing can release dust owing to abrasion of dressed seed; the drift of dust containing insecticide active ingredients is harmful to honey bees. Therefore, we developed a device for drills that uses partial recirculation and filtration of the air by means of an antipollen and an electrostatic filter. RESULTS: Tests were carried out by simulating the sowing of seed treated with imidacloprid, thiamethoxam, clothianidin and fipronil. Dust released by the drill in different configurations was analysed to assess its mass and active ingredient concentration, size distribution and particle number concentration. In general, particles with a diameter smaller than 2.5 and 10 µm represent about 40 and 75% of the total dust mass respectively. The finest size fraction (<1 µm) contains a higher content of active ingredient. The prototype equipped with both antipollen and electrostatic filters always showed a reduction in dust emission greater than 90% in terms of both total mass and active ingredient amount, with a greater efficiency in the reduction in particles below 4 µm. CONCLUSION: This study presents an engineering solution addressing dust losses during sowing, contributes to the description of abrasion dust fractions and provides suggestions for further development of the prototype. © 2016 Society of Chemical Industry.


Assuntos
Filtros de Ar , Produção Agrícola/instrumentação , Poeira/análise , Produção Agrícola/métodos , Inseticidas/análise , Neonicotinoides/análise , Tamanho da Partícula , Pólen , Pirazóis/análise , Sementes , Zea mays
13.
J Allergy Clin Immunol Pract ; 4(3): 445-452.e4, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26897304

RESUMO

BACKGROUND: A recent park study found a substantial preventive effect of a new nasal filter for seasonal allergic rhinitis. However, the nasal filter still needs to prove that it is sufficiently convenient and comfortable for everyday use during a regular pollen season. OBJECTIVE: The objective of this study was to evaluate the usability of the nasal filter (Rhinix, Rhinix ApS, Aarhus, Denmark) in a large population. METHODS: An observational, open-label study (NCT02108379) conducted during the main grass pollen season in 2014 in Denmark included 1073 participants with seasonal allergic rhinitis, with or without asthma. Participants received the filters for a 2-week use period. Identical online questionnaires were answered after each week of use. End points included ratings on satisfaction, usage, and interest in continued use, stratified by allergy and asthma severity. RESULTS: There were 834 filter users in week 1; 634 of these continued use in week 2. After week 1, 630 (76%) expressed interest in continued use of the filters. Participants who continued use in week 2 had higher screening scores for nasal symptoms (P = .01), had more severe asthma for those with asthma (P = .04), and were more dissatisfied with their usual treatment compared with the participants who discontinued use (P = .03). CONCLUSIONS: Of 834 new users, 630 stated interest in continued use of the filters. On the basis of the findings of this large observational usability study, the nasal filters appear sufficiently convenient and comfortable to use and thus clinically relevant for symptom management for many allergy sufferers.


Assuntos
Filtros de Ar , Rinite Alérgica Sazonal/prevenção & controle , Adulto , Alérgenos/imunologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Nariz , Poaceae/imunologia , Pólen/imunologia
14.
Environ Technol ; 37(6): 681-93, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26235832

RESUMO

Biofiltration of volatile organic compounds is still considered an emerging technology. Its reliability remains questionable as no data is available regarding process intrinsic repeatability. Herein, two identically operated toluene biofiltration systems are comprehensively compared, during long-term operation (129 days). Globally, reactors responded very similarly, even during transient conditions, with, for example, strong biological activities from the first days of operation, and comparable periods of lower removal efficiency (81.2%) after exposure to high inlet loads (140 g m(-3) h(-1)). Regarding steady states, very similar maximum elimination capacities up to 99 g m(-3) h(-1) were attained. Estimation of the process repeatability, with the paired samples Student's t-test, indicated no statistically significant difference between elimination capacities. Repeatability was also established for several descriptors of the process such as the carbon dioxide and biomass production, the pH and organic content of the leachates, and the moisture content of the packing material. While some parameters, such as the pH, presented a remarkably low divergence between biofilters (coefficient of variability of 1.4%), others, such as the organic content of the leachates, presented higher variability (30.6%) due to an uneven biomass lixiviation associated with stochastic hydrodynamics and biomass repartitions. Regarding process efficiency, it was established that less than 10% of fluctuation is to be expected between the elimination capacities of identical biofilter set-ups. A further statistical comparison between the first halves of the biofilter columns indicated very similar coefficients of variability, confirming the repeatability of the process, for different biofilter lengths.


Assuntos
Filtros de Ar , Poluentes Atmosféricos/metabolismo , Poluição do Ar/prevenção & controle , Reatores Biológicos , Tolueno/metabolismo , Óxido de Alumínio/química , Dióxido de Carbono/metabolismo , Esgotos/microbiologia , Dióxido de Silício/química
15.
ACS Appl Mater Interfaces ; 7(45): 25313-20, 2015 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-26505783

RESUMO

Recently, with the increased attention to indoor air quality, antimicrobial air filtration techniques have been studied widely to inactivate hazardous airborne microorganisms effectively. In this study, we demonstrate herbal extract incorporated (HEI) nanofibers synthesized by an electrospinning technique and their application to antimicrobial air filtration. As an antimicrobial herbal material, an ethanolic extract of Sophora flavescens, which exhibits great antibacterial activity against pathogens, was mixed with the polymer solution for the electrospinning process. We measured various characteristics of the synthesized HEI nanofibers, such as fiber morphology, fiber size distribution, and thermal stability. For application of the electrospun HEI nanofibers, we made highly effective air filters with 99.99% filtration efficiency and 99.98% antimicrobial activity against Staphylococcus epidermidis. The pressure drop across the HEI nanofiber air filter was 4.75 mmH2O at a face air velocity of 1.79 cm/s. These results will facilitate the implementation of electrospun HEI nanofiber techniques to control air quality and protect against hazardous airborne microorganisms.


Assuntos
Filtros de Ar , Bactérias/isolamento & purificação , Filtração/métodos , Nanofibras/química , Nanotecnologia/métodos , Extratos Vegetais/química , Nanofibras/ultraestrutura , Tamanho da Partícula , Sophora/química , Espectroscopia de Infravermelho com Transformada de Fourier
16.
J Allergy Clin Immunol ; 136(6): 1566-1572.e5, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26141263

RESUMO

BACKGROUND: A recently reported small, out-of-season environmental exposure unit study found nasal filters to be efficacious in preventing seasonal allergic rhinitis (AR). However, nasal filters still need to show efficacy in a natural setting in a regular pollen season. OBJECTIVE: We sought to evaluate the efficacy of nasal filters (Rhinix; Rhinix ApS, Aarhus, Denmark) for the prevention of symptoms related to seasonal AR. METHODS: The trial was a single-center, randomized (1:1), double-blind, placebo-controlled crossover clinical trial (NCT02108574) conducted over 2 days in the main grass pollen season in June 2014 in Aarhus, Denmark, on 65 adults with proven grass allergy. A total nasal symptom score (TNSS) consisting of blocked nose, runny nose, nasal itching, and sneezing was used to evaluate symptoms. The difference in daily∑ TNSS (the sum of 13 ratings) was the primary outcome measure. The difference in maximum TNSS (highest score, 13 ratings) was also evaluated. RESULTS: The nasal filters significantly reduced daily∑ TNSSs (P = .03) and maximum TNSSs (P = .03) compared with placebo. Median relative reductions were 40% for daily∑ TNSSs (P = .02), 43% for maximum TNSSs (P = .004), 83% for daily∑ sneezing (P = .001), 75% for daily∑ watery eyes (P = .02), and 53% for daily∑ runny nose (P = .005) when compared with placebo. The nasal filters were well tolerated, and no serious adverse events were recorded. CONCLUSION: Statistically significant and clinically relevant reductions were achieved for the primary outcome measure of daily∑ TNSS, for maximum TNSS and for a subset of individual symptoms. The results support the preventive role of nasal filters for managing seasonal AR.


Assuntos
Filtros de Ar , Rinite Alérgica Sazonal/prevenção & controle , Adolescente , Adulto , Alérgenos/imunologia , Estudos Cross-Over , Dinamarca , Método Duplo-Cego , Feminino , Humanos , Masculino , Nariz , Poaceae/imunologia , Pólen/imunologia , Adulto Jovem
17.
PLoS One ; 10(5): e0126481, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25974109

RESUMO

Controlling bioaerosols has become more important with increasing participation in indoor activities. Treatments using natural-product nanomaterials are a promising technique because of their relatively low toxicity compared to inorganic nanomaterials such as silver nanoparticles or carbon nanotubes. In this study, antimicrobial filters were fabricated from natural Euscaphis japonica nanoparticles, which were produced by nebulizing E. japonica extract. The coated filters were assessed in terms of pressure drop, antimicrobial activity, filtration efficiency, major chemical components, and cytotoxicity. Pressure drop and antimicrobial activity increased as a function of nanoparticle deposition time (590, 855, and 1150 µg/cm2(filter) at 3-, 6-, and 9-min depositions, respectively). In filter tests, the antimicrobial efficacy was greater against Staphylococcus epidermidis than Micrococcus luteus; ~61, ~73, and ~82% of M. luteus cells were inactivated on filters that had been coated for 3, 6, and 9 min, respectively, while the corresponding values were ~78, ~88, and ~94% with S. epidermidis. Although statistically significant differences in filtration performance were not observed between samples as a function of deposition time, the average filtration efficacy was slightly higher for S. epidermidis aerosols (~97%) than for M. luteus aerosols (~95%). High-performance liquid chromatography (HPLC) and electrospray ionization-tandem mass spectrometry (ESI/MS) analyses confirmed that the major chemical compounds in the E. japonica extract were 1(ß)-O-galloyl pedunculagin, quercetin-3-O-glucuronide, and kaempferol-3-O-glucoside. In vitro cytotoxicity and disk diffusion tests showed that E. japonica nanoparticles were less toxic and exhibited stronger antimicrobial activity toward some bacterial strains than a reference soluble nickel compound, which is classified as a human carcinogen. This study provides valuable information for the development of a bioaerosol control system that is environmental friendly and suitable for use in indoor environments.


Assuntos
Filtros de Ar/microbiologia , Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Magnoliopsida/química , Nanopartículas/química , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Microbiologia do Ar , Anti-Infecciosos/isolamento & purificação , Infecções Bacterianas/prevenção & controle , Humanos , Micrococcus luteus/efeitos dos fármacos , Extratos Vegetais/isolamento & purificação , Staphylococcus epidermidis/efeitos dos fármacos
18.
Environ Technol ; 36(5-8): 881-9, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25220430

RESUMO

Changes in the number and species diversity of cultivable microorganisms in a newly developed plate-type biofilter during filtration of various volatile pollutants were studied. The novelty of the investigation is the monitoring of microorganism succession in different parts of biofilter plates with original packing material consisting of birch fibre and needle-punched non-woven fabric. It was shown that the largest number of fungi and yeasts develop on the top and middle, while bacteria develop on the bottom and middle parts of plates. The number of microorganisms depends on the origin of the pollutant, the pH and temperature inside the biofilter and the moisture of the porous plates. The statistically significant correlation between the number of microorganisms and inlet concentration of acetone was estimated, while ammonia showed a negative influence on yeast distribution. Paecilomyces variotii, Rhodotorula mucilaginosa and Bacillus subtilis were the most common organisms found during filtration of all examined volatiles; however, some differences of microbial communities in different parts of the biofilter plates and filtrated volatile compounds were obtained.


Assuntos
Filtros de Ar/microbiologia , Consórcios Microbianos , Compostos Orgânicos Voláteis/isolamento & purificação , Acetona , Amônia , Bactérias , Fungos , Xilenos , Leveduras
19.
Appl Microbiol Biotechnol ; 99(1): 33-42, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25492419

RESUMO

Biofilters treating high-concentration gaseous volatile organic compounds (VOC) can be subject to bed clogging induced by excess biomass accumulation. In this study, O3 was continuously injected into biofilters to control biomass. Its effects on the performance of the biofilters and on biomass accumulation were investigated. Four identical biofilters designed to treat gaseous toluene were operated for 70 days, and three of them were continuously injected with O3 at different concentrations (from 80 to 320 mg/m(3)). The results showed that continuous O3 injection could effectively keep the bed pressure drop stable and had no adverse effect on toluene removal when O3 concentrations were 180-220 mg/m(3). The maximum toluene elimination capacity of the four biofilters was 140 g-toluene/m(3)/h, and the bed pressure drop of the biofilter fed with 180-220 mg/m(3) O3 remained below 3 mmH2O/m throughout the operation period. The biomass accumulation rates of the three biofilters with O3 at 80-320 mg/m(3) were lowered by 0.15-0.25 g/L/day compared with the biofilter without O3. The decreases in biomass accumulation resulted in higher void fractions of the filter beds with O3 injection. Carbon balance analysis indicated that CO2 production had increased while biomass accumulation and leachate waste production decreased in response to O3 injection. Based on the experimental results, it was concluded here that continuous O3 injection can reduce increases in bed pressure effectively, preserve VOC removal capacity, and prevent production of extra leachate waste.


Assuntos
Filtros de Ar , Poluentes Atmosféricos/metabolismo , Anti-Infecciosos/metabolismo , Reatores Biológicos/microbiologia , Filtração/métodos , Ozônio/metabolismo , Tolueno/metabolismo , Poluentes Atmosféricos/isolamento & purificação , Biomassa , Tolueno/isolamento & purificação
20.
Appl Microbiol Biotechnol ; 99(1): 67-76, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24831028

RESUMO

The purpose of this work was to evaluate the technical and economical feasibility of converting three chemical scrubbers in series to biotrickling filters (BTFs) for the simultaneous removal of H2S and volatile organic compounds (VOCs). The conversion of the full-scale scrubbers was based on previous conversion protocols. Conversion mainly required replacing the original carrier material and recycle pumps as well as modifying the controls and operation of the reactors. Complete removal of H2S and VOCs on a routine basis was reached at neutral pH in a longer period of time compared to previous conversions reported. Biotrickling filters operated at a gas contact time of about 1.4 s per reactor and at pH controlled between 6.5 and 6.8. Inlet average concentrations below 10 ppmv of H2S and below 5 ppmv for VOCs were often completely removed. The first and second bioreactors played a primary role in H2S removal. Year-round operation of the biotrickling filters proved the ability of the system to handle progressive load increases of H2S and VOCs. However, fast, sudden load changes often lead to reduced removal efficiencies. Odor analyses showed average removal efficiencies above 80%. Gas chromatography-mass spectrometry of selected samples showed that outlet odor concentration was due to limited removal of VOCs. The conversion showed was economically viable taking into account the theoretical consumption of chemicals needed for the absorption and oxidation of both H2S and VOCs.


Assuntos
Filtros de Ar , Reatores Biológicos/microbiologia , Filtração/métodos , Sulfeto de Hidrogênio/metabolismo , Compostos Orgânicos Voláteis/metabolismo , Cromatografia Gasosa-Espectrometria de Massas , Concentração de Íons de Hidrogênio , Odorantes/análise
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