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1.
BMJ Open ; 11(9): e046040, 2021 09 08.
Artigo em Inglês | MEDLINE | ID: mdl-34497075

RESUMO

OBJECTIVES: To estimate concentration-response relationships for particulate matter (PM) and black carbon (BC) in relation to mortality in cohorts from three Swedish cities with comparatively low pollutant levels. SETTING: Cohorts from Gothenburg, Stockholm and Umeå, Sweden. DESIGN: High-resolution dispersion models were used to estimate annual mean concentrations of PM with aerodynamic diameter ≤10 µm (PM10) and ≤2.5 µm (PM2.5), and BC, at individual addresses during each year of follow-up, 1990-2011. Moving averages were calculated for the time windows 1-5 years (lag1-5) and 6-10 years (lag6-10) preceding the outcome. Cause-specific mortality data were obtained from the national cause of death registry. Cohort-specific HRs were estimated using Cox regression models and then meta-analysed including a random effect of cohort. PARTICIPANTS: During the study period, 7 340 cases of natural mortality, 2 755 cases of cardiovascular disease (CVD) mortality and 817 cases of respiratory and lung cancer mortality were observed among in total 68 679 individuals and 689 813 person-years of follow-up. RESULTS: Both PM10 (range: 6.3-41.9 µg/m3) and BC (range: 0.2-6.8 µg/m3) were associated with natural mortality showing 17% (95% CI 6% to 31%) and 9% (95% CI 0% to 18%) increased risks per 10 µg/m3 and 1 µg/m3 of lag1-5 exposure, respectively. For PM2.5 (range: 4.0-22.4 µg/m3), the estimated increase was 13% per 5 µg/m3, but less precise (95% CI -9% to 40%). Estimates for CVD mortality appeared higher for both PM10 and PM2.5. No association was observed with respiratory mortality. CONCLUSION: The results support an effect of long-term air pollution on natural mortality and mortality in CVD with high relative risks also at low exposure levels. These findings are relevant for future decisions concerning air quality policies.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Poluentes Atmosféricos/efeitos adversos , Poluentes Atmosféricos/análise , Poluição do Ar/efeitos adversos , Poluição do Ar/análise , Carbono , Causas de Morte , Exposição Ambiental/efeitos adversos , Exposição Ambiental/análise , Humanos , Material Particulado/efeitos adversos , Material Particulado/análise , Suécia/epidemiologia
2.
Environ Pollut ; 290: 118105, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34523530

RESUMO

Road transport is the main anthropogenic source of NOx in Europe, affecting human health and ecosystems. Thus, mitigation policies have been implemented to reduce on-road vehicle emissions, particularly through the Euro standard limits. To evaluate the effectiveness of these policies, we calculated NO2 and NOx concentration trends using air quality and meteorological measurements conducted in three European cities over 26 years. These data were also employed to estimate the trends in NOx emission factors (EFNOx, based on inverse dispersion modeling) and NO2:NOx emission ratios for the vehicle fleets under real-world driving conditions. In the period 1998-2017, Copenhagen and Stockholm showed large reductions in both the urban background NOx concentrations (-2.1 and -2.6% yr-1, respectively) and EFNOx at curbside sites (68 and 43%, respectively), proving the success of the Euro standards in diminishing NOx emissions. London presented a modest decrease in urban background NOx concentrations (-1.3% yr-1), while EFNOx remained rather constant at the curbside site (Marylebone Road) due to the increase in public bus traffic. NO2 primary emissions -that are not regulated- increased until 2008-2010, which also reflected in the ambient concentrations. This increase was associated with a strong dieselization process and the introduction of new after-treatment technologies that targeted the emission reduction of other species (e.g., greenhouse gases or particulate matter). Thus, while regulations on ambient concentrations of specific species have positive effects on human health, the overall outcomes should be considered before widely adopting them. Emission inventories for the on-road transportation sector should include EFNOx derived from real-world measurements, particularly in urban settings.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Poluentes Atmosféricos/análise , Poluição do Ar/análise , Ecossistema , Monitoramento Ambiental , Humanos , Londres , Óxidos de Nitrogênio/análise , Emissões de Veículos/análise
3.
Artigo em Inglês | MEDLINE | ID: mdl-34202261

RESUMO

When mortality or other health outcomes attributable to fine particulate matter (PM2.5) are estimated, the same exposure-response function (ERF) is usually assumed regardless of the source and composition of the particles, and independently of the spatial resolution applied in the exposure model. While several recent publications indicate that ERFs based on exposure models resolving within-city gradients are steeper per concentration unit (µgm-3), the ERF for PM2.5 recommended by the World Health Organization does not reflect this observation and is heavily influenced by studies based on between-city exposure estimates. We evaluated the potential health benefits of three air pollution abatement strategies: electrification of light vehicles, reduced use of studded tires, and introduction of congestion charges in Stockholm and Gothenburg, using different ERFs. We demonstrated that using a single ERF for PM2.5 likely results in an underestimation of the effect of local measures and may be misleading when evaluating abatement strategies. We also suggest applying ERFs that distinguish between near-source and regional contributions of exposure to PM2.5. If separate ERFs are applied for near-source and regional PM2.5, congestion charges as well as a reduction of studded tire use are estimated to be associated with a significant reduction in the mortality burden in both Gothenburg and Stockholm. In some scenarios the number of premature deaths is more than 10 times higher using separate ERFs in comparison to using a single ERF irrespective of sources as recommended by the WHO. For electrification, the net change in attributable deaths is small or within the uncertainty range depending on the choice of ERF.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Poluentes Atmosféricos/análise , Poluição do Ar/efeitos adversos , Poluição do Ar/análise , Poluição do Ar/prevenção & controle , Cidades , Material Particulado/análise
4.
Behav Sci (Basel) ; 11(6)2021 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-34073168

RESUMO

Cave Art in the Upper Paleolithic presents a boost of creativity and visual thinking. What can explain these savant-like paintings? The normal brain function in modern man rarely supports the creation of highly detailed paintings, particularly the convincing representation of animal movement, without extensive training and access to modern technology. Differences in neuro-signaling and brain anatomy between modern and archaic Homo sapiens could also cause differences in perception. The brain of archaic Homo sapiens could perceive raw detailed information without using pre-established top-down concepts, as opposed to the common understanding of the normal modern non-savant brain driven by top-down control. Some ancient genes preserved in modern humans may be expressed in rare disorders. Researchers have compared Cave Art with art made by people with autism spectrum disorder. We propose that archaic primary consciousness, as opposed to modern secondary consciousness, included a savant-like perception with a superior richness of details compared to modern man. Modern people with high frequencies of Neanderthal genes, have notable anatomical features such as increased skull width in the occipital and parietal visual areas. We hypothesize that the anatomical differences are functional and may allow a different path to visual perception.

5.
Scand J Public Health ; : 14034948211010024, 2021 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-33977822

RESUMO

AIMS: To estimate the overall health impact of transferring commuting trips from car to bicycle. METHODS: In this study registry information on the location of home and work for residents in Stockholm County was used to obtain the shortest travel route on a network of bicycle paths and roads. Current modes of travel to work were based on travel survey data. The relation between duration of cycling and distance cycled was established as a basis for selecting the number of individuals that normally would drive a car to work, but have a distance to work that they could bicycle within 30 minutes. The change in traffic flows was estimated by a transport model (LuTrans) and effects on road traffic injuries and fatalities were estimated by using national hospital injury data. Effects on air pollution concentrations were modelled using dispersion models. RESULTS: Within the scenario, 111,000 commuters would shift from car to bicycle. On average the increased physical activity reduced the one-year mortality risk by 12% among the additional bicyclists. Including the number of years lost due to morbidity, the total number of disability adjusted life-years gained was 696. The amount of disability adjusted life-years gained in the general population due to reduced air pollution exposure was 471. The number of disability adjusted life-years lost by traffic injuries was 176. Also including air pollution effects among bicyclists, the net benefit was 939 disability adjusted life-years per year. CONCLUSIONS: Large health benefits were estimated by transferring commuting by car to bicycle.

6.
Materials (Basel) ; 14(4)2021 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-33546176

RESUMO

The scientific community has made great efforts in advancing magnetic hyperthermia for the last two decades after going through a sizeable research lapse from its establishment. All the progress made in various topics ranging from nanoparticle synthesis to biocompatibilization and in vivo testing have been seeking to push the forefront towards some new clinical trials. As many, they did not go at the expected pace. Today, fruitful international cooperation and the wisdom gain after a careful analysis of the lessons learned from seminal clinical trials allow us to have a future with better guarantees for a more definitive takeoff of this genuine nanotherapy against cancer. Deliberately giving prominence to a number of critical aspects, this opinion review offers a blend of state-of-the-art hints and glimpses into the future of the therapy, considering the expected evolution of science and technology behind magnetic hyperthermia.

7.
Artigo em Inglês | MEDLINE | ID: mdl-33572991

RESUMO

In the Nordic countries (Denmark, Finland, Iceland, Norway and Sweden), the Urban Green Infrastructure (UGI) has been traditionally targeted at reducing flood risk. However, other Ecosystem Services (ES) became increasingly relevant in response to the challenges of urbanization and climate change. In total, 90 scientific articles addressing ES considered crucial contributions to the quality of life in cities are reviewed. These are classified as (1) regulating ES that minimize hazards such as heat, floods, air pollution and noise, and (2) cultural ES that promote well-being and health. We conclude that the planning and design of UGI should balance both the provision of ES and their side effects and disservices, aspects that seem to have been only marginally investigated. Climate-sensitive planning practices are critical to guarantee that seasonal climate variability is accounted for at high-latitude regions. Nevertheless, diverging and seemingly inconsistent findings, together with gaps in the understanding of long-term effects, create obstacles for practitioners. Additionally, the limited involvement of end users points to a need of better engagement and communication, which in overall call for more collaborative research. Close relationships and interactions among different ES provided by urban greenery were found, yet few studies attempted an integrated evaluation. We argue that promoting interdisciplinary studies is fundamental to attain a holistic understanding of how plant traits affect the resulting ES; of the synergies between biophysical, physiological and psychological processes; and of the potential disservices of UGI, specifically in Nordic cities.


Assuntos
Ecossistema , Qualidade de Vida , Cidades , Finlândia , Islândia , Noruega , Países Escandinavos e Nórdicos , Suécia
8.
Environ Sci Pollut Res Int ; 28(13): 16264-16271, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33341921

RESUMO

Epidemiologic studies on health effects of air pollution usually rely on time-series of ambient monitoring data or on spatially modelled levels. Little is known how well these estimate residential outdoor and indoor levels. We investigated the agreement of measured residential black carbon (BC) levels outdoors and indoors with fixed-site monitoring data and with levels calculated using a Gaussian dispersion model. One-week residential outdoor and indoor BC measurements were conducted for 15 families living in central Stockholm. Time-series from urban background and street-level monitors were compared to these measurements. The observed weekly concentrations were also standardized to reflect annual averages, using urban background levels, and compared spatially to long-term levels as estimated by dispersion modelling. Weekly average outdoor BC level was 472 ng/m3 (range 261-797 ng/m3). The corresponding fixed-site urban background and street levels were 313 and 1039 ng/m3, respectively. Urban background variation explained 50% of the temporal variation in residential outdoor levels averaged over 24 h. Modelled residential long-term outdoor levels were on average comparable with the standardized measured home outdoor levels, and explained 49% of the spatial variability. The median indoor/outdoor ratio across all addresses was 0.79, with no difference between day and night time. Common exposure estimation approaches in the epidemiology of health effects related to BC displayed high validity for residencies in central Stockholm. Urban background monitored levels explained half of the outdoor day-to-day variability at residential addresses. Long-term dispersion modelling explained half of the spatial differences in outdoor levels. Indoor BC concentrations tended to be somewhat lower than outdoor levels.


Assuntos
Poluentes Atmosféricos , Poluição do Ar em Ambientes Fechados , Poluição do Ar , Poluentes Atmosféricos/análise , Poluição do Ar/análise , Poluição do Ar em Ambientes Fechados/análise , Carbono/análise , Monitoramento Ambiental , Humanos
9.
Artigo em Inglês | MEDLINE | ID: mdl-33092089

RESUMO

This study aims to use dispersion-modeled concentrations of nitrogen oxides (NOx) and black carbon (BC) to estimate bicyclist exposures along a network of roads and bicycle paths. Such modeling was also performed in a scenario with increased bicycling. Accumulated concentrations between home and work were thereafter calculated for both bicyclists and drivers of cars. A transport model was used to estimate traffic volumes and current commuting preferences in Stockholm County. The study used individuals' home and work addresses, their age, sex, and an empirical model estimate of their expected physical capacity in order to establish realistic bicycle travel distances. If car commuters with estimated physical capacity to bicycle to their workplace within 30 min changed their mode of transport to bicycle, >110,000 additional bicyclists would be achieved. Time-weighted mean concentrations along paths were, among current bicyclists, reduced from 25.8 to 24.2 µg/m3 for NOx and 1.14 to 1.08 µg/m3 for BC. Among the additional bicyclists, the yearly mean NOx dose from commuting increased from 0.08 to 1.03 µg/m3. This would be expected to yearly cause 0.10 fewer deaths for current bicycling levels and 1.7 more deaths for additional bicycling. This increased air pollution impact is much smaller than the decrease in the total population.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Ciclismo , Emissões de Veículos , Poluentes Atmosféricos/análise , Poluição do Ar/efeitos adversos , Poluição do Ar/análise , Automóveis , Exposição Ambiental/análise , Humanos , Transportes , Emissões de Veículos/análise , Emissões de Veículos/toxicidade
10.
Artigo em Inglês | MEDLINE | ID: mdl-32481677

RESUMO

We have studied the associations between exhaust particles and birth weight. Adjustments were made for ozone and potential confounding factors at the individual level. The study included all singletons conceived between August 2003 and February 2013 with mothers living in Greater Stockholm. We obtained record-based register data from the Swedish Medical Birth Register. Data concerning the parents were provided by Statistics Sweden. Exposure levels for nearly 187,000 pregnancies were calculated using a validated air quality dispersion model with input from a detailed emission database. A higher socioeconomic status was associated with higher levels of exhaust particles at the home address. In this region, with rather low air pollution levels, the associations between levels of exhaust particles and birth weight were negative for all three of the studied exposure windows (i.e., first and second trimester and full pregnancy). For the entire pregnancy, the linear decrease in birth weight was 7.5 grams (95% CI-12.0; -2.9) for an increase in exposure, corresponding to the inter quartile range (IQR = 209 ng/m3). We also found that the risk of being born small for gestational age increased with the level of exhaust particles in all three exposure windows, but these associations were not statistically significant.


Assuntos
Poluentes Atmosféricos/toxicidade , Poluição do Ar/estatística & dados numéricos , Peso ao Nascer , Exposição Materna/estatística & dados numéricos , Emissões de Veículos/toxicidade , Poluentes Atmosféricos/análise , Poluição do Ar/efeitos adversos , Poluição do Ar/análise , Feminino , Humanos , Recém-Nascido , Exposição Materna/efeitos adversos , Ozônio , Material Particulado/análise , Gravidez , Suécia , Emissões de Veículos/análise
11.
J Orthop Surg Res ; 15(1): 155, 2020 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-32303232

RESUMO

BACKGROUND: Simultaneous measurement of electromyography (EMG) and local muscle oxygenation is proposed in an isometric loading model adjusted for patients that have undergone spinal surgery. METHODS: Twelve patients with degenerative lumbar spinal stenosis (DLSS) were included. They were subjected to a test protocol before and after surgery. The protocol consisted of two parts, a dynamic and an isometric Ito loading with a time frame of 60 s and accompanying rest of 120 s. The Ito test was repeated three times. EMG was measured bilaterally at the L4 level and L2 and was recorded using surface electrodes and collected (Biopac Systems Inc.). EMG signal was expressed as RMS and median frequency (MF). Muscle tissue oxygen saturation (MrSO2) was monitored using a near-infrared spectroscopy (NIRS) device (INVOS® 5100C Oxymeter). Two NIRS sensors were positioned bilaterally at the L4 level. The intensity of the leg and back pain and perceived exertion before, during, and after the test was evaluated with a visual analogue scale (VAS) and Borg RPE-scale, respectively. RESULTS: All patients were able to perform and complete the test protocol pre- and postoperatively. A consistency of lower median and range values was noted in the sensors of EMG1 (15.3 µV, range 4.5-30.7 µV) and EMG2 (13.6 µV, range 4.0-46.5 µV) that were positioned lateral to NIRS sensors at L4 compared with EMG3 (18.9 µV, range 6.5-50.0 µV) and EMG4 (20.4 µV, range 7.5-49.0 µV) at L2. Right and left side of the erector spinae exhibited a similar electrical activity behaviour over time during Ito test (60 s). Regional MrSO2 decreased over time during loading and returned to the baseline level during recovery on both left and right side. Both low back and leg pain was significantly reduced postoperatively. CONCLUSION: Simultaneous measurement of surface EMG and NIRS seems to be a promising tool for objective assessment of paraspinal muscle function in terms of muscular activity and local muscle oxygenation changes in response to isometric trunk extension in patients that have undergone laminectomy for spinal stenosis.


Assuntos
Oxigênio/metabolismo , Músculos Paraespinais/fisiologia , Estenose Espinal/cirurgia , Suporte de Carga/fisiologia , Dor nas Costas/diagnóstico , Eletromiografia , Exercício Físico , Feminino , Humanos , Contração Isométrica/fisiologia , Laminectomia/efeitos adversos , Masculino , Pessoa de Meia-Idade , Medição da Dor , Músculos Paraespinais/metabolismo , Músculos Paraespinais/fisiopatologia , Espectroscopia de Luz Próxima ao Infravermelho
12.
ACS Appl Mater Interfaces ; 12(4): 4295-4307, 2020 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-31904927

RESUMO

We have developed a reproducible and facile one step strategy for the synthesis of doxorubicin loaded magnetoliposomes by using a thin-layer evaporation method. Liposomes of around 200 nm were made of 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) and iron oxide nanoparticles (NPs) with negative, positive, and hydrophobic surfaces that were incorporated outside, inside, or between the lipid bilayers, respectively. To characterize how NPs are incorporated in liposomes, advanced cryoTEM and atomic force microscope (AFM) techniques have been used. It was observed that only when the NPs are attached outside the liposomes, the membrane integrity is preserved (lipid melt transition shifts to 38.7 °C with high enthalpy 34.8 J/g) avoiding the leakage of the encapsulated drug while having good colloidal properties and the best heating efficiency under an alternating magnetic field (AMF). These magnetoliposomes were tested with two cancer cell lines, MDA-MB-231 and HeLa cells. First, 100% of cellular uptake was achieved with a high cell survival (above 80%), which is preserved (83%) for doxorubicin-loaded magnetoliposomes. Then, we demonstrate that doxorubicin release can be triggered by remote control, using a noninvasive external AMF for 1 h, leading to a cell survival reduction of 20%. Magnetic field conditions of 202 kHz and 30 mT seem to be enough to produce an effective heating to avoid drug degradation. In conclusion, these drug-loaded magnetoliposomes prepared in one step could be used for drug release on demand at a specific time and place, efficiently using an external AMF to reduce or even eliminate side effects.


Assuntos
Antineoplásicos/química , Preparações de Ação Retardada/química , Sistemas de Liberação de Medicamentos/métodos , Lipossomos/química , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Preparações de Ação Retardada/farmacologia , Doxorrubicina/química , Doxorrubicina/farmacologia , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos/instrumentação , Liberação Controlada de Fármacos , Humanos , Campos Magnéticos , Nanopartículas/química
13.
Disabil Rehabil ; 42(6): 770-778, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-30451551

RESUMO

Background: The presence of early balance impairment in patients with Parkinson's disease has not been fully investigated.Purpose: The purpose of this study was to examine balance and mobility, self-perceived unsteadiness, self-reported falls, and effects of medication on balance among patients at their first visit to a neurological clinic and during the ensuing five years.Materials and methods: The participants were collected from a prospective longitudinal study. One hundred and forty-five patients with idiopathic Parkinson's disease and 31 healthy controls were included. The outcome measures were the Berg Balance Scale, the Timed Up and Go, the Postural Stability test and a questionnaire.Results: At their first visit to the neurological clinic, the patients performed less well on the Berg Balance Scale (p < 0.001, r = 0.36), the Timed Up and Go (p < 0.001, r = 0.32), and the Postural Stability test (p < 0.001, r = 0.35) compared with the controls. In addition, a higher percentage of the patients reported self-perceived unsteadiness (p < 0.001, phi = 0.47). During the ensuing five years, balance and mobility worsened both with and without medication (p < 0.01, r = 0.24-0.37), although with small median differences.Conclusions: Further studies are needed to confirm that minor balance impairments exist even at the time of diagnosis and worsen during the ensuing five years.IMPLICATIONS FOR REHABILITATIONImpairments in balance and mobility may occur early in Parkinson's disease, especially in the elderly patients, and seem to worsen during the first five years.There is a need to use sensitive outcome measures and to ask the patients about unsteadiness and falls to detect balance impairment in this cohort.Parkinsonian medication has a limited effect on balance and may preferably be complemented with balance exercises to target balance impairment early in Parkinson's disease.


Assuntos
Limitação da Mobilidade , Doença de Parkinson , Equilíbrio Postural , Acidentes por Quedas/estatística & dados numéricos , Estudos de Casos e Controles , Seguimentos , Humanos , Estudos Longitudinais , Doença de Parkinson/complicações , Doença de Parkinson/tratamento farmacológico , Estudos Prospectivos , Suécia
14.
Environ Health Perspect ; 127(10): 107012, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31663781

RESUMO

BACKGROUND: Long-term exposure to particulate matter (PM) in ambient air has been associated with cardiovascular mortality, but few studies have considered incident disease in relation to PM from different sources. OBJECTIVES: We aimed to study associations between long-term exposure to different types of PM and sources, and incident ischemic heart disease (IHD) and stroke in three Swedish cities. METHODS: Based on detailed emission databases, monitoring data, and high-resolution dispersion models, we calculated source contributions to PM with aerodynamic diameter ≤10µm (PM10), PM with aerodynamic diameter ≤2.5µm (PM2.5), and black carbon (BC) from road wear, traffic exhaust, residential heating, and other sources in Gothenburg, Stockholm, and Umeå. Registry data for participants from four cohorts were used to obtain incidence of IHD and stroke for first hospitalization or death. We constructed time windows of exposure for same-year, 1- to 5-y, and 6- to 10-y averages preceding incidence from annual averages at residential addresses. Risk estimates were based on random effects meta-analyses of cohort-specific Cox proportional hazard models. RESULTS: We observed 5,166 and 3,119 incident IHD and stroke cases, respectively, in 114,758 participants. Overall, few consistent associations were observed between the different air pollution measures and IHD or stroke incidence. However, same-year levels of ambient locally emitted BC (range: 0.01-4.6 µg/m3) were associated with a 4.0% higher risk of incident stroke per interquartile range (IQR), 0.30 µg/m3 [95% confidence interval (CI): 0.04, 7.8]. This association was primarily related to BC from traffic exhaust. PM10 (range: 4.4-52 µg/m3) and PM2.5 (range: 2.9-22 µg/m3) were not associated with stroke. Associations with incident IHD were observed only for PM2.5 exposure from residential heating. DISCUSSION: Few consistent associations were observed between different particulate components and IHD or stroke. However, long-term residential exposure to locally emitted BC from traffic exhaust was associated with stroke incidence. The comparatively low exposure levels may have contributed to the paucity of associations. https://doi.org/10.1289/EHP4757.


Assuntos
Poluição do Ar/estatística & dados numéricos , Exposição Ambiental/estatística & dados numéricos , Isquemia Miocárdica/epidemiologia , Material Particulado , Acidente Vascular Cerebral/epidemiologia , Poluentes Atmosféricos , Carbono , Doenças Cardiovasculares/epidemiologia , Estudos de Coortes , Feminino , Hospitalização , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , Suécia/epidemiologia , Emissões de Veículos
15.
Biosensors (Basel) ; 9(3)2019 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-31533330

RESUMO

The specific binding of oligonucleotide-tagged 100 nm magnetic nanoparticles (MNPs) to rolling circle products (RCPs) is investigated using our newly developed differential homogenous magnetic assay (DHMA). The DHMA measures ac magnetic susceptibility from a test and a control samples simultaneously and eliminates magnetic background signal. Therefore, the DHMA can reveal details of binding kinetics of magnetic nanoparticles at very low concentrations of RCPs. From the analysis of the imaginary part of the DHMA signal, we find that smaller MNPs in the particle ensemble bind first to the RCPs. When the RCP concentration increases, we observe the formation of agglomerates, which leads to lower number of MNPs per RCP at higher concentrations of RCPs. The results thus indicate that a full frequency range of ac susceptibility observation is necessary to detect low concentrations of target RCPs and a long amplification time is not required as it does not significantly increase the number of MNPs per RCP. The findings are critical for understanding the underlying microscopic binding process for improving the assay performance. They furthermore suggest DHMA is a powerful technique for dynamically characterizing the binding interactions between MNPs and biomolecules in fluid volumes.


Assuntos
Técnicas Biossensoriais/métodos , Nanopartículas de Magnetita/química
16.
Heliyon ; 5(8): e02325, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31467994

RESUMO

In this study, we have taken the concept of water treatment by functionalized magnetic particles one step forward by integrating the technology into a complete proof of concept, which included the preparation of surface modified beads, their use as highly selective absorbents for heavy metals ions (Zinc, Nickel), and their performance in terms of magnetic separation. The separation characteristics were studied both through experiments and by simulations. The data gathered from these experimental works enabled the elaboration of various scenarios for Life Cycle Analysis (LCA). The LCA showed that the environmental impact of the system is highly dependent on the recovery rate of the magnetic particles. The absolute impact on climate change varied significantly among the scenarios studied and the recovery rates. The results support the hypothesis that chelation specificity, magnetic separation and bead recovery should be optimized to specific targets and applications.

17.
ACS Sens ; 4(9): 2381-2388, 2019 09 27.
Artigo em Inglês | MEDLINE | ID: mdl-31397152

RESUMO

Assays are widely used for detection of various targets, including pathogens, drugs, and toxins. Homogeneous assays are promising for the realization of point-of-care diagnostics as they do not require separation, immobilization, or washing steps. For low concentrations of target molecules, the speed and sensitivity of homogeneous assays have hitherto been limited by slow binding kinetics, time-consuming amplification steps, and the presence of a high background signal. Here, we present a homogeneous differential magnetic assay that utilizes a differential magnetic readout that eliminates previous limitations of homogeneous assays. The assay uses a gradiometer sensor configuration combined with precise microfluidic sample handling. This enables simultaneous differential measurement of a positive test sample containing a synthesized Vibrio cholerae target and a negative control sample, which reduces the background signal and increases the readout speed. Very low concentrations of targets down to femtomolar levels are thus detectable without any additional amplification of the number of targets. Our homogeneous differential magnetic assay method opens new possibilities for rapid and highly sensitive diagnostics at the point of care.


Assuntos
Bioensaio/instrumentação , Fenômenos Magnéticos , DNA Bacteriano/análise , DNA Bacteriano/genética , Dispositivos Lab-On-A-Chip , Limite de Detecção , Técnicas de Amplificação de Ácido Nucleico , Vibrio cholerae/genética , Vibrio cholerae/isolamento & purificação
18.
Sci Total Environ ; 674: 279-287, 2019 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-31004903

RESUMO

The traffic microenvironment has been shown to be a major contributor to the total personal exposure of black carbon (BC), and is key to local actions aiming at reducing health risks associated with such exposure. The main aim of the study was to get a better understanding of the determinants of traffic-related personal exposure to BC in an urban environment. Personal exposure to ambient levels of BC was monitored while walking, cycling and traveling by bus or car along four streets and while cycling alternative routes simultaneously. Monitoring was performed during morning and afternoon peak hours and at midday, with a portable aethalometer recording one-minute mean values. In all, >4000 unique travel passages were performed. Stepwise Linear Regression was used to assess predictors to personal exposure levels of BC. The personal BC concentration ranged 0.03-37 µg/m3. The average concentrations were lowest while walking (1.7 µg/m3) and highest traveling by bus (2.7 µg/m3). However, only 22% of the variability could be explained by travel mode, urban background BC and wind speed. BC concentrations measured inside a car were on average 33% lower than measured simultaneously outside the car. Choosing an alternative bicycle route with less traffic resulted in up to 1.4 µg/m3 lower personal exposure concentrations. In conclusion, traveling by bus rendered the highest personal BC concentrations. But when taking travel time and inhalation rate into account, the travel-related exposure dose was predicted to be highest during walking and cycling. It is however probable that the benefits from physical activity outweigh health risks associated with this higher exposure dose. It is clear that road traffic makes an important contribution to personal exposure to BC regardless of mode of intra-urban transport. Our data suggest that commuting along routes with lower BC levels would substantially decrease commuter's exposure.


Assuntos
Poluentes Atmosféricos/análise , Exposição Ambiental/análise , Material Particulado/análise , Fuligem/análise , Automóveis , Ciclismo , Exposição Ambiental/estatística & dados numéricos , Monitoramento Ambiental , Suécia , Viagem , Emissões de Veículos/análise , Caminhada
19.
Artigo em Inglês | MEDLINE | ID: mdl-30901873

RESUMO

In this study, the effects on daily mortality in Stockholm associated with short-term exposure to ultrafine particles (measured as number of particles with a diameter larger than 4 nm, PNC4), black carbon (BC) and coarse particles (PM2.5⁻10) have been compared with the effects from more common traffic-pollution indicators (PM10, PM2.5 and NO2) and O3 during the period 2000⁻2016. Air pollution exposure was estimated from measurements at a 20 m high building in central Stockholm. The associations between daily mortality lagged up to two days (lag 02) and the different air pollutants were modelled by using Poisson regression. The pollutants with the strongest indications of an independent effect on daily mortality were O3, PM2.5⁻10 and PM10. In the single-pollutant model, an interquartile range (IQR) increase in O3 was associated with an increase in daily mortality of 2.0% (95% CI: 1.1⁻3.0) for lag 01 and 1.9% (95% CI: 1.0⁻2.9) for lag 02. An IQR increase in PM2.5⁻10 was associated with an increase in daily mortality of 0.8% (95% CI: 0.1⁻1.5) for lag 01 and 1.1% (95% CI: 0.4⁻1.8) for lag 02. PM10 was associated with a significant increase only at lag 02, with 0.8% (95% CI: 0.08⁻1.4) increase in daily mortality associated with an IQR increase in the concentration. NO2 exhibits negative associations with mortality. The significant excess risk associated with O3 remained significant in two-pollutant models after adjustments for PM2.5⁻10, BC and NO2. The significant excess risk associated with PM2.5⁻10 remained significant in a two-pollutant model after adjustment for NO2. The significantly negative associations for NO2 remained significant in two-pollutant models after adjustments for PM2.5⁻10, O3 and BC. A potential reason for these findings, where statistically significant excess risks were found for O3, PM2.5⁻10 and PM10, but not for NO2, PM2.5, PNC4 and BC, is behavioral factors that lead to misclassification in the exposure. The concentrations of O3 and PM2.5⁻10 are in general highest during sunny and dry days during the spring, when exposure to outdoor air tend to increase, while the opposite applies to NO2, PNC4 and BC, with the highest concentrations during the short winter days with cold weather, when people are less exposed to outdoor air.


Assuntos
Poluentes Atmosféricos/efeitos adversos , Mortalidade/tendências , Dióxido de Nitrogênio/efeitos adversos , Ozônio/efeitos adversos , Material Particulado/efeitos adversos , Poluentes Atmosféricos/análise , Humanos , Masculino , Dióxido de Nitrogênio/análise , Ozônio/análise , Material Particulado/análise , Estações do Ano , Suécia/epidemiologia
20.
Artigo em Inglês | MEDLINE | ID: mdl-30609753

RESUMO

In this study, an Air Quality Health Index (AQHI) for Stockholm is introduced as a tool to capture the combined effects associated with multi-pollutant exposure. Public information regarding the expected health risks associated with current or forecasted concentrations of pollutants and pollen can be very useful for sensitive persons when planning their outdoor activities. For interventions, it can also be important to know the contribution from pollen and the specific air pollutants, judged to cause the risk. The AQHI is based on an epidemiological analysis of asthma emergency department visits (AEDV) and urban background concentrations of NOx, O3, PM10 and birch pollen in Stockholm during 2001⁻2005. This analysis showed per 10 µg·m⁻3 increase in the mean of same day and yesterday an increase in AEDV of 0.5% (95% CI: -1.2⁻2.2), 0.3% (95% CI: -1.4⁻2.0) and 2.5% (95% CI: 0.3⁻4.8) for NOx, O3 and PM10, respectively. For birch pollen, the AEDV increased with 0.26% (95% CI: 0.18⁻0.34) for 10 pollen grains·m⁻3. In comparison with the coefficients in a meta-analysis, the mean values of the coefficients obtained in Stockholm are smaller. The mean value of the risk increase associated with PM10 is somewhat smaller than the mean value of the meta-coefficient, while for O3, it is less than one fifth of the meta-coefficient. We have not found any meta-coefficient using NOx as an indicator of AEDV, but compared to the mean value associated with NO2, our value of NOx is less than half as large. The AQHI is expressed as the predicted percentage increase in AEDV without any threshold level. When comparing the relative contribution of each pollutant to the total AQHI, based on monthly averages concentrations during the period 2015⁻2017, there is a tangible pattern. The AQHI increase associated with NOx exhibits a relatively even distribution throughout the year, but with a clear decrease during the summer months due to less traffic. O3 contributes to an increase in AQHI during the spring. For PM10, there is a significant increase during early spring associated with increased suspension of road dust. For birch pollen, there is a remarkable peak during the late spring and early summer during the flowering period. Based on monthly averages, the total AQHI during 2015⁻2017 varies between 4 and 9%, but with a peak value of almost 16% during the birch pollen season in the spring 2016. Based on daily mean values, the most important risk contribution during the study period is from PM10 with 3.1%, followed by O3 with 2.0%.


Assuntos
Poluentes Atmosféricos/efeitos adversos , Poluição do Ar/efeitos adversos , Asma/etiologia , Asma/fisiopatologia , Poeira/análise , Material Particulado/efeitos adversos , Medição de Risco/estatística & dados numéricos , Serviço Hospitalar de Emergência/estatística & dados numéricos , Humanos , Estações do Ano , Índice de Gravidade de Doença , Suécia
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