265 research outputs found
An in vitro versus in vivo toxicogenomics investigation of prenatal exposures to tobacco smoke
Approximately 1 million women smoke during pregnancy despite evidence demonstrating serious juvenile and/or adult diseases being linked to early-life exposure to cigarette smoke. Susceptibility could be determined by factors in previous generations, i.e. pre-natal or ‘maternal’ exposures to toxins. Pre-natal exposure to airborne pollutants such as mainstream cigarette smoke has been shown to induce early-life insults (i.e. gene changes) in Offspring that serve as biomarkers for disease later in life. In this investigation, we have evaluated genome-wide changes in the lungs of mouse Dams and their juvenile Offspring exposed pre-natally to mainstream cigarette smoke. An additional lung model was tested alongside the murine model, as a means to find an alternative in vitro, human tissue-based replacement for the use of animals in medical research. Our toxicogenomic and bioinformatic results indicated that in utero exposure altered the genetic patterns of the foetus that could put them at greater risk for developing a range of chronic illnesses in later-life. The genes altered in the in vitro, cell culture model were reflected in the murine model of pre-natal exposure to MCS. The use of alternative in vitro models derived from human medical waste tissues could be viable options to achieve human end-point data and to conduct research that meets the remits for scientists to undertake the 3Rs practises
The bioreactivity of the sub-10 μm component of volcanic ash: Soufrière Hills volcano, Montserrat
With the recent eruption of the Icelandic volcano Eyafallajökull and resulting ash cloud over much of Europe there was considerable concern about possible respiratory hazards. Volcanic ash can contain minerals that are known human respiratory health hazards such as cristobalite. Short-term ash exposures can cause skin sores, respiratory and ocular irritations and exacerbation of pre-existing lung conditions such as asthma. Long-term occupational level exposures to crystalline silicon dioxide can cause lung inflammation, oedema, fibrosis and cancer. The potential health effects would be dependent on factors including mineralogy, surface chemistry, size, and levels and duration of exposure. Bulk ash from the Soufrière Hills volcano was sourced and inhalable (<2.5μm) ash samples prepared and physicochemically characterised. The fine ash samples were tested for bioreactivity by SDS-PAGE which determined the strength of binding between mineral grains and lung proteins. Selected proteins bound tightly to cristobalite, and bound loosely to other ash components. A positive correlation was seen between the amount of SiO2 in the sample and the strength of the binding. The strength of binding is a function of the mineral’s bioreactivity, and therefore, a potential geo-biomarker of respiratory risk
Transparency in non-technical summaries to sustain the 3Rs in respiratory diseases research
Non-Technical Project Summaries (NTS) are legal documents that were first introduced by the Directive 2010/63/EU to enhance transparency within scientific animal experimentation. Researchers intending to conduct biological research on animal models must fulfil the NTS requirements by outlining their proposed use of animals and how they plan to implement the Three Rs (replacement, reduction and refinement of animal use) in their experiments. This study outlines a novel systematic analysis approach that enables the assessment of NTS transparency based on the accuracy of reporting of certain Three Rs-specific information. This potentially customisable strategy could help toward the development of practical guidelines for use by Animal Welfare and Ethical Review Bodies (AWERBs) in establishments conducting animal research, in the process of scrutinising NTS during their pre-submission review of proposed licence applications. This could help to identify gaps in reporting of Three Rs-specific information relating to the planned animal experiments, which represents a remarkable step toward achieving greater openness in scientific communication. This study supports the concept that NTS transparency can promote the implementation of non-animal alternatives in fields where this is currently lacking, such as respiratory disease research. Although NTS were originally conceived as informative documents for a lay audience, we can conclude that data in NTS can be successfully used as a basis for systematic analysis. By reviewing the NTS, the experimental limitations of the currently available replacement strategies can also be highlighted, potentially pinpointing where there is a need for future method development
Testing particulate matter toxicity via in vitro methods: What should be tested?
Unlike other toxic substances, usually of a known
chemical formula, air particulate matter (PM) is a
mixture of solid and liquid particles. The most frequently
used tests are in vitro in nature and examine ‘cell
viability’ following 24-hour exposure to PM. In most
cases, PM induces sub-toxic viability responses but other
key cell functions are not detected.
The aim of this study was to compare the toxicity
profiles of engineered NPs: zinc oxide (ZnO), crystalline
form of silicon oxide (SiO2), and nickel (Ni), which are
frequently present in ambient air pollution. Three
different assays (acellular and cellular) were chosen to
test PM biological targets: (1) plasmid scission assay –
detecting DNA damage (indicative of the ability to
produce reactive oxygen species; ROS; Figure 1); (2)
haemolysis assay – informing about red blood cells
(RBCs) membranes integrity; (3) proliferation assay
inspected on HUVEC (human umbilical vein endothelial
cells) at 24, 48 and 72 hours post-exposure to NPs
Survey of research approaches utilised in the scholarship of teaching and learning publications
The Scholarship of Teaching and Learning (SoTL) has been described as the fastest growing academic development movement in higher education. As this field of inquiry matures, there is a need to understand how SoTL research is conducted. The purpose of our study was to inform this debate by investigating research approaches used in SoTL publications. We analysed 223 empirical research studies published from 2012 to 2014 in three explicitly focused SoTL journals. We classified the studies as either qualitative, quantitative, or mixed methods using an analytical framework devised from existing literature on research methods. We found that the use of the three research designs was fairly evenly distributed across the papers examined: qualitative (37.2%), quantitative (29.6%), and mixed methods (33.2%). However, there was an over-reliance on data collection from a single source in 83.9% of papers analysed, and this source was primarily students. There was some, but limited, evidence of the use of triangulation through the use of multiple data collection instruments (e.g. survey, assessment tasks, grade databases). Similarly, only one-third of publications classified as mixed methods integrated the analysis and interpretation of the qualitative and quantitative data equally within the study. We conclude that current SoTL research is characterised by methodological pluralism but could be advanced through inclusion of more diverse approaches, such as close reading, and adoption of strategies known to enhance the quality of research, for example, triangulation and visual representation
Combustion particles emitted during church services: Implications for human respiratory health
Burning candles and incense generate particulate matter (PM) that produces poor indoor air quality and may cause human pulmonary problems. This study physically characterised combustion particles collected in a church during services. In addition, the emissions from five types of candles and two types of incense were investigated using a combustion chamber. The plasmid scission assay was used to determine the oxidative capacities of these church particles. The corresponding risk factor (CRf) was derived from the emission factor (Ef) and the oxidative DNA damage, and used to evaluate the relative respiratory exposure risks. Real-time PM measurements in the church during candle–incense burning services showed that the levels (91.6 μg/m3 for PM10; 38.9 μg/m3 for PM2.5) exceeded the European Union (EU) air quality guidelines. The combustion chamber testing, using the same environmental conditions, showed that the incense Ef for both PM10 (490.6– 587.9 mg/g) and PM2.5 (290.1–417.2 mg/g) exceeded that of candles; particularly the PM2.5 emissions. These CRf results suggested that the exposure to significant amounts of incense PM could result in a higher risk of oxidative DNA adducts (27.4–32.8 times) than tobacco PM. The generation and subsequent inhalation of PM during church activities may therefore pose significant risks in terms of respiratory health effects
The internal microstructure and fibrous mineralogy of fly-ash from coal-burning power stations
Coal fly-ash (CFA) is a significant environmental pollutant that presents a respiratory hazard when airborne. Although previous studies have identified the mineral components of CFA, there is a paucity of information on the structural habits of these minerals. Samples from UK, Polish and Chinese power stations were studied to further our understanding of the factors that affect CFA geochemistry and mineralogy. ICP-MS, FE-SEM/EDX, XRD, and laser diffraction were used to study physicochemical characteristics. Analysis revealed important differences in the elemental compositions and particle size distributions of samples between sites. Microscopy of HF acid-etched CFA revealed the mullite present possesses a fibrous habit; fibres ranged in length between 1–10μm. Respirable particles (<10μm) were frequently observed to contain fibrous mullite. We propose that the biopersistence of these refractory fibres in the lung environment could be contributing towards chronic lung diseases seen in communities and individuals continually exposed to high levels of CFA
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