Risk assessment of released cellulose nanocrystals – mimicking inhalatory exposure

Cellulose nanocrystals (CNCs) exhibit advantageous chemical and mechanical properties that render them attractive for a wide range of applications. During the life-cycle of CNC containing materials the nanocrystals could be released and become airborne, posing a potential inhalatory exposure risk towards humans. Absent reliable and dose-controlled models that mimic this exposure in situ is a central issue in gaining an insight into the CNC-lung interaction. Here, an Air Liquid Interface Cell Exposure system (ALICE), previously designed for studies of spherical nanoparticles, was used for the first time to establish a realistic physiological exposure test method for inhaled fiber shaped nano-objects; in this case, CNCs isolated from cotton. Applying a microscopy based approach the spatially homogenous deposition of CNCs was demonstrated as a prerequisite of the functioning of the ALICE. Furthermore, reliability and controllability of the system to nebulise high aspect ratio nanomaterials (HARN, e.g. CNCs) was shown. This opens the potential to thoroughly investigate the inhalatory risk of CNCs in vitro using a realistic exposure system

Pengembangan Ruang Terbuka Hijau berdasarkan Distribusi Suhu Permukaan di Kabupaten Bandung

Bandung Regency is experiencing increased of air temperature, particularly in the urban area. High air temperature in urban areas is caused by increasing built-up areas and declining green open space. Green open space should be built to lower air temperature and to create a comfortable micro climate. Green open space should be developed at locations with high air temperature to reach its efficacy. This research used spatial analysis to generate air temperature distribution map. The map was used as the basis in developing green open space. The map showed that green open spaces should be developed at several sub-districts, namely Margahayu, Margaasih, Dayeuhkolot, Baleendah, Bojongsoang, Rancaekek, Cileunyi, Pameungpeuk, and Majalaya sub-districts

Pengembangan Ruang Terbuka Hijau berdasarkan Distribusi Suhu Permukaan di Kabupaten Bandung

Bandung Regency is experiencing increased of air temperature, particularly in the urban area. High air temperature in urban areas is caused by increasing built-up areas and declining green open space. Green open space should be built to lower air temperature and to create a comfortable micro climate. Green open space should be developed at locations with high air temperature to reach its efficacy. This research used spatial analysis to generate air temperature distribution map. The map was used as the basis in developing green open space. The map showed that green open spaces should be developed at several sub-districts, namely Margahayu, Margaasih, Dayeuhkolot, Baleendah, Bojongsoang, Rancaekek, Cileunyi, Pameungpeuk, and Majalaya sub-districts

Biological response of an in vitro human 3D lung cell model exposed to brake wear debris varies based on brake pad formulation

Wear particles from automotive friction brake pads of various sizes, morphology, and chemical composition are significant contributors towards particulate matter. Knowledge concerning the potential adverse effects following inhalation exposure to brake wear debris is limited. Our aim was, therefore, to generate brake wear particles released from commercial low-metallic and non-asbestos organic automotive brake pads used in mid-size passenger cars by a full-scale brake dynamometer with an environmental chamber simulating urban driving and to deduce their potential hazard in vitro. The collected fractions were analysed using scanning electron microscopy via energy-dispersive X-ray spectroscopy (SEM-EDS) and Raman microspectroscopy. The biological impact of the samples was investigated using a human 3D multicellular model consisting of human epithelial cells (A549) and human primary immune cells (macrophages and dendritic cells) mimicking the human epithelial tissue barrier. The viability, morphology, oxidative stress, and (pro-)inflammatory response of the cells were assessed following 24 h exposure to similar to 12, similar to 24, and similar to 48 A mu g/cm(2) of non-airborne samples and to similar to 3.7 A mu g/cm(2) of different brake wear size fractions (2-4, 1-2, and 0.25-1 A mu m) applying a pseudo-air-liquid interface approach. Brake wear debris with low-metallic formula does not induce any adverse biological effects to the in vitro lung multicellular model. Brake wear particles from non-asbestos organic formulated pads, however, induced increased (pro-)inflammatory mediator release from the same in vitro system. The latter finding can be attributed to the different particle compositions, specifically the presence of anatase.Web of Science9272351233

Assessment of a panel of interleukin-8 reporter lung epithelial cell lines to monitor the pro-inflammatory response following zinc oxide nanoparticle exposure under different cell culture conditions

Stably transfected lung epithelial reporter cell lines pose an advantageous alternative to replace complex experimental techniques to monitor the pro-inflammatory response following nanoparticle (NP) exposure. Previously, reporter cell lines have been used under submerged culture conditions, however, their potential usefulness in combination with air-liquid interface (ALI) exposures is currently unknown. Therefore, the aim of the present study was to compare a panel of interleukin-8 promoter (pIL8)-reporter cell lines (i.e. green or red fluorescent protein (GFP, RFP), and luciferase (Luc)), originating from A549 lung epithelial type II-like cells cells, following NPs exposure under both submerged and ALI conditions. All cell lines were exposed to zinc oxide (ZnO) NPs at 0.6 and 6.2 μg/cm 2 for 3 and 16 hours under both submerged and ALI conditions. Following physicochemical characterization, the cytotoxic profile of the ZnO-NPs was determined for each exposure scenario. Expression of IL-8 from all cell types was analyzed at the promoter level and compared to the mRNA (qRT-PCR) and protein level (ELISA). In summary, each reporter cell line detected acute pro-inflammatory effects following ZnO exposure under each condition tested. The pIL8-Luc cell line was the most sensitive in terms of reporter signal strength and onset velocity following TNF-α treatment. Both pIL8-GFP and pIL8-RFP also showed a marked signal induction in response to TNF-α, although only after 16 hrs. In terms of ZnO-NP-induced cytotoxicity pIL8-RFP cells were the most affected, whilst the pIL8-Luc were found the least responsive. In conclusion, the use of fluorescence-based reporter cell lines can provide a useful tool in screening the pro-inflammatory response following NP exposure in both submerged and ALI cell cultures. The online version of this article (doi:10.1186/s12989-015-0104-6) contains supplementary material, which is available to authorized users

Carotid stiffness and physical activity in elderly : a short report of the SAPALDIA 3 cohort study

Regular physical activity has been shown to reduce cardiovascular disease risk in the general population. While smaller studies in specified groups (highly trained versus untrained individuals) indicate a certain dose-dependent effect of physical activity on the reduction of carotid stiffness (an indicator of subclinical vascular disease), it is unclear whether this association is present in a representative sample. Thus, we investigated this question cross-sectionally in participants from the population-based Swiss Cohort Study on Air Pollution And Lung and Heart Diseases In Adults (SAPALDIA).; Self-reported total, moderate and vigorous physical activity and distensibility as a measure of local arterial stiffness among 1636 participants aged 50 to 81 years without clinically manifest diseases were evaluated. Mixed regression models were used to examine associations of physical activity intensity with distensibility.; Vigorous physical activity, but not total nor moderate physical activity, was significantly associated with increased distensibility (= reduced carotid stiffness) in univariate analyses (percent change in the geometric mean and 95% confidence interval per 1 standard deviation increment in vigorous physical activity = 2.54 (0.69; 4.43), p>0.01; in total physical activity = 1.62 (-0.22; 3.50), p = 0.08; in moderate physical activity = 0.70 (-1.12; 2.56), p = 0.45). These associations disappeared when we additionally adjusted for age.; After adjustment for the most important confounders and risk factors, we found no evidence for an association of physical activity with carotid stiffness in the general middle aged to elderly population

Changes in physical activity behavior and development of cardiovascular risk in children

Abstract Funding Acknowledgements Type of funding sources: Foundation. Main funding source(s): Swiss National Foundation Background Prevention of cardiovascular (CV) disease should start early in life. The study aimed to investigate the association of changes in physical activity, sedentary behavior and cardiorespiratory fitness (CRF) with development of body mass index (BMI), blood pressure (BP) and retinal microvascular health in children over four years. Methods In 2014, 391 children aged 6-8 years were screened, and thereof 262 children were reexamined after four years following standardized protocols. Retinal arteriolar (CRAE) and venular diameters were measured by a retinal vessel analyzer. CRF was objectively assessed by a 20m shuttle run, physical activity and sedentary behavior by use of a questionnaire. Results Children who achieved higher CRF levels reduced their BMI (β [95% CI] -0.35 [-0.46 to -0.25] kg/m2 per stage, P ≤ 0.001) and thereby developed wider CRAE (β [95% CI] 0.25 [0.24 to 0.48] µm per stage, P = 0.03) at follow-up. Moreover, children with elevated or high systolic BP at baseline, but lower levels of sedentary behavior during the observation period, had wider CRAE at follow-up (β [95% CI] -0.37 [-0.66 to -0.08] µm per 10 min/d, P = 0.013). Conclusion An increase of CRF over four years was associated with a reduced BMI and consequently wider retinal arterioles at follow-up. In children with elevated or high systolic BP, a reduction of sedentary behavior by merely 10 min per day significantly improved retinal microvascular health as a primary prevention strategy to promote childhood health and combat development of manifest CV disease later in life. </jats:sec