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Background Digital health can support health care in low- and middle-income countries (LMICs) by overcoming problems of distance, poor infrastructure and the need to provide community practitioners with specialist support. We used five RESPIRE countries as exemplars (Bangladesh, India, Indonesia, Malaysia, Pakistan) to identify the digital health solutions that are valuable in their local setting, worked together with local clinicians and researchers to explore digital health policy, electricity/ICT infrastructure, and socio-cultural factors influencing users’ ability to access, adopt and utilise digital health. Methods We adopted the Joanna Briggs Institute’s scoping review protocol and followed the Cochrane Rapid Review method to accelerate the review process, using the Implementation and Operation of Mobile Health projects framework and The Extended Technology Acceptance Model of Mobile Telephony to categorise the results. We conducted the review in four stages: (1) establishing value, (2) identifying digital health policy, (3) searching for evidence of infrastructure, design, and end-user adoption, (4) local input to interpret relevance and adoption factors. We used open-source national/international statistics such as the World Health Organization, International Telecommunication Union, Groupe Speciale Mobile, and local news/articles/government statistics to scope the current status, and systematically searched five databases for locally relevant exemplars. Results We found 118 studies (2015-2021) and 114 supplementary online news articles and national statistics. Digital health policy was available in all countries, but scarce skilled labour, lack of legislation/interoperability support, and interrupted electricity and internet services were limitations. Older patients, women and those living in rural areas were least likely to have access to ICT infrastructure. Renewable energy has potential in enabling digital health care. Low usage mobile data and voice service packages are relatively affordable options for mHealth in the five countries. Conclusions Effective implementation of digital health technologies requires a supportive policy, stable electricity infrastructures, affordable mobile internet service, and good understanding of the socio-economic context in order to tailor the intervention such that it functional, accessible, feasible, user-friendly and trusted by the target users. We suggest a checklist of contextual factors that developers of digital health initiatives in LMICs should consider at an early stage in the development process.

Respiratory disorders are responsible for considerable morbidity, health care utilisation, societal costs and approximately one in five deaths worldwide [1-4]. Yet, despite this substantial health and societal burden – which particularly affects the world’s poorest populations and as such is a major contributor to global health inequalities – respiratory disorders have historically not received the policy priority they warrant. For example, despite causing an estimated 1000 deaths per day, less than half of the world’s countries collect data on asthma prevalence (http://www.globalasthmareport.org/). This is true for both communicable and non-communicable respiratory disorders, many of which are either amenable to treatment or preventable.

Contaminated drinking water is one of the most important environmental contributors to the human disease burden. Monitoring of water for the presence of pathogens is an essential part of ensuring drinking water safety. In order to assess water quality it is essential to have methods available to sample and detect the type, level and viability of pathogens in water which are effective, cheap, quick, sensitive, and where possible high throughput. Nanotechnology has the potential to drastically improve the monitoring of waterborne pathogens when compared to conventional approaches. To date, there have been no reviews that outline the applications of nanotechnology in this area despite increasing exploitation of nanotechnology for this purpose. This review is therefore the first overview of the state-of-the-art in the application of nanotechnology to waterborne pathogen sampling and detection schemes. Research in this field has been centered on the use of engineered nanomaterials. The effectiveness and limitations of nanomaterial-based approaches is outlined. A future outlook of the advances that are likely to emerge in this area, as well as recommendations for areas of further research are provided.

Summary There is an urgent need for sufficient knowledge to allow reliable assessment of the risks associated with nanomaterials. The formulation of an intelligent testing strategy (ITS) that allows safety assessment across materials is required to overcome the current need of testing each nanomaterial on a case-by-case basis. By taking into consideration the research landscape, the available tools and the stakeholders involved, the ITS-NANO consortium developed a stepping-stone based research framework which can, when implemented, deliver the information required for flexible and broadly acceptable ITS and risk assessment (RA) protocols. It was identified that in order to derive this knowledge, there needs to be research emphasis on linking physicochemical identifiers to exposure and hazard identifiers, and attention should be given to a number of key cross-cutting issues have been identified which, among other things, include development of standards, dose metrics, high throughput techniques, modelling and integration into regulatory frameworks. Finally, the developed approach must be coherent and continuously updatable, supporting the unified framework required to ensure that we acquire sufficient, rigorously validated knowledge formulation of a robust reliable ITS and RA as quickly as possible.

PARTICLE_RISK was one of the first multidisciplinary projects funded by the European Commission's Framework Programme that was responsible for evaluating the implications of nanomaterial (NM) exposure on human health. This project was the basis for this review which identifies the challenges that exist within the assessment of NM risk. We have retrospectively reflected on the findings of completed nanotoxicology studies to consider what progress and advances have been made within the risk assessment of NMs, as well as discussing the direction that nanotoxicology research is taking and identifying the limitations and failings of existing research. We have reflected on what commonly encountered challenges exist and explored how these issues may be resolved. In particular, the following is discussed (i) NM selection (ii) NM physico-chemical characterisation; (iii) NM dispersion; (iv) selection of relevant doses and concentrations; (v) identification of relevant models, target sites and endpoints; (vi) development of alternatives to animal testing; and (vii) NM risk assessment. These knowledge gaps are relatively well recognised by the scientific community and recommendations as to how they may be overcome in the future are provided. It is hoped that this will help develop better defined hypothesis driven research in the future that will enable comprehensive risk assessments to be conducted for NMs. Importantly, the nanotoxicology community has responded and adapted to advances in knowledge over recent years to improve the approaches used to assess NM hazard, exposure and risk. It is vital to learn from existing information provided by ongoing or completed studies to avoid unnecessary duplication of effort, and to offer guidance on aspects of the experimental design that should be carefully considered prior to the start of a new study.

The development of alternative testing strategies (ATS) for hazard assessment of new and emerging materials is high on the agenda of scientists, funders, and regulators. The relatively large number of nanomaterials on the market and under development means that an increasing emphasis will be placed on the use of reliable, predictive ATS when assessing their safety. We have provided recommendations as to how ATS development for assessment of nanomaterial hazard may be accelerated. Predefined search terms were used to identify the quantity and distribution of peer-reviewed publications for nanomaterial hazard assessment following inhalation, ingestion, or dermal absorption. A summary of knowledge gaps relating to nanomaterial hazard is provided to identify future research priorities and areas in which a rich data set might exist to allow ATS identification. Consultation with stakeholders (e.g., academia, industry, regulators) was critical to ensure that current expert opinion was reflected. The gap analysis revealed an abundance of studies that assessed the local and systemic impacts of inhaled particles, and so ATS are available for immediate use. Development of ATS for assessment of the dermal toxicity of chemicals is already relatively advanced, and these models should be applied to nanomaterials as relatively few studies have assessed the dermal toxicity of nanomaterials to date. Limited studies have investigated the local and systemic impacts of ingested nanomaterials. If the recommendations for research prioritization proposed are adopted, it is envisioned that a comprehensive battery of ATS can be developed to support the risk assessment process for nanomaterials. Some alternative models are available for immediate implementation, while others require more developmental work to become widely adopted. Case studies are included that can be used to inform the selection of alternative models and end points when assessing the pathogenicity of fibers and mode of action of nanomaterial toxicity.

Pulmonary fibrosis is a debilitating disease affecting up to 2 million people worldwide, with a median survival rate of only 3 years after diagnosis. The aim of this study was to evaluate a potential protein biomarker (Cocoacrisp, CC) to identify the onset of pulmonary fibrosis. A model of fibrosis was induced via intratracheal instillation of bleomycin, and samples were collected during the early phase of the disease. Immunohistochemical identification of CC was carried out in lung tissue from the bleomycin model. Quantification by image analysis showed CC levels were doubled (p

Background Associations between smoking and the development of tobacco-related diseases in humans have historically been assessed by epidemiological studies. These studies are further complicated by the number of chemicals used in tobacco and individual smoking habits. An alternative approach is required to assess the biological responses. Objective Toxicogenomics was carried out to identify early molecular markers for events in pulmonary injury resulting from tobacco smoke components (TSC) exposure. Materials and methods EpiAirway-100 cells were exposed at the air/liquid interface to representative particle (nicotine; cadmium) and vapour phase [formaldehyde (FA) and ethyl carbamate] components of cigarette smoke. Microarray technology was used to compare expression profiles of human genes associated with toxicity and drug resistance, from control and TSC-treated respiratory epithelium (n=5/dose). Results Using the GEArray 'toxicology and drug resistance' microarray followed by significance analysis of microarray analysis, 42 mRNA transcripts were found to be significantly altered by the TSC exposure. The vapour [ethyl carbamate, FA and particle (nicotine, cadmium)] phase TSC exhibited differential transcriptional responses that could not be attributed to their chemical phase. The transcriptional changes could be classified according to a functional family, where ethyl carbamate, FA and cadmium classified as carcinogens, demonstrated the highest gene homology when compared with the noncarcinogen, nicotine. Discussion Analysis of the microarray data and further confirmation (reverse transcriptase-PCR) identified three potential biomarkers for TSC-induced injury. These three genes (CYP7A1, HMOX1 and PTGS1) are highly upregulated and have been linked with mechanistic pathways of disease.

One of the first lines of defence to inhaled toxins is the barrier formed by the tracheobronchial epithelium, making this the ideal region for studying the toxicity of inhaled substances. This study utilises a highly differentiated, three-dimensional, in vitro model of human upper respiratory tract epithelium (EpiAirway-100) to measure the acute toxicological responses to well-characterised tobacco smoke components. To determine the suitability of this model for screening inhaled toxicants, the EpiAirway tissue model (ETM) was treated apically with tobacco smoke components (nicotine, formaldehyde, cadmium, urethane) which are known to induce a variety of toxic effects (e.g. cytotoxic, thrombogenic, carcinogenic). A range of concentrations were used to model different mechanisms and severity of toxicity which were then compared to known in vivo responses. Similar trends in stress response occurred, with distinct alterations to the tissue in response to all four toxins. At high concentrations, cell viability decreased and tight junctions were degraded, but at sub-toxic concentrations epithelial resistance (indicating tissue integrity) increased 20–60% from control. This peak in resistance coincided with an increase in secreted protein levels, elevated cytokine release and goblet cell hyperplasia and hypertrophy. In conclusion, acute exposure to tobacco smoke components induces measurable toxic responses within human respiratory epithelium. Sub-toxic concentrations appear to illicit a protective response by increasing mucus secretion and mediating immune responses via cytokine release. These responses are comparable to human in vivo responses, indicating potential for the ETM as a tool for screening the toxicity of inhaled compounds.

Engineered nanomaterials (NMs) offer great technological advantages but their risks to human health are still not fully understood. An increasing body of evidence suggests that some NMs are capable of distributing from the site of exposure to a number of secondary organs. The research into the toxicity posed by the NMs in these secondary organs is expanding due to the realisation that some materials may reach and accumulate in these target sites. The translocation to secondary organs includes, but is not limited to, the hepatic, central nervous, cardiovascular and renal systems. Current data indicates that pulmonary exposure is associated with low (inhalation route-0.00001-1% of total applied dose-24 h) translocation of virtually insoluble NMs such as iridium, carbon black, gold and polystyrene, while slightly higher translocation has been observed for NMs with either slow (e.g., silver, cerium dioxide and quantum dots) or fast (e.g., zinc oxide) solubility. The translocation of NMs following intratracheal, intranasal and pharyngeal aspiration is higher (up to 10% of administered dose), however the relevance of these routes for risk assessment is questionable. Uptake of the materials from the gastrointestinal tract seems to follow the same pattern as inhalation translocation, whereas the dermal uptake of NMs is generally reported to be low. The toxicological effects in secondary organs include oxidative stress, inflammation, cytotoxicity and dysfunction of cellular and physiological processes. For toxicological and risk evaluation, further information on the toxicokinetics and persistence of NMs is crucial. The overall aim of this review is to outline the data currently available in the literature on the biokinetics, accumulation, toxicity and eventual fate of NMs in order to assess the potential risks posed by NMs to secondary organs.

BACKGROUND:To assess the risk of all nanomaterials (NMs) on a case-by-case basis is challenging in terms of financial, ethical and time resources. Instead a more intelligent approach to knowledge gain and risk assessment is required.METHODS:A framework of future research priorities was developed from the accorded opinion of experts covering all major stake holder groups (government, industry, academia, funders and NGOs). It recognises and stresses the major topics of physicochemical characterisation, exposure identification, hazard identification and modelling approaches as key components of the current and future risk assessment of NMs.RESULTS:The framework for future research has been developed from the opinions of over 80 stakeholders, that describes the research priorities for effective development of an intelligent testing strategy (ITS) to allow risk evaluation of NMs. In this context, an ITS is a process that allows the risks of NMs to be assessed accurately, effectively and efficiently, thereby reducing the need to test NMs on a case-by-case basis.For each of the major topics of physicochemical characterisation, exposure identification, hazard identification and modelling, key-priority research areas are described via a series of stepping stones, or hexagon diagrams structured into a time perspective. Importantly, this framework is flexible, allowing individual stakeholders to identify where their own activities and expertise are positioned within the prioritisation pathway and furthermore to identify how they can effectively contribute and structure their work accordingly. In other words, the prioritisation hexagon diagrams provide a tool that individual stakeholders can adapt to meet their own particular needs and to deliver an ITS for NMs risk assessment. Such an approach would, over time, reduce the need for testing by increasing the reliability and sophistication of in silico approaches.The manuscript includes an appraisal of how this framework relates to the current risk assessment approaches and how future risk assessment could adapt to accommodate these new approaches. A full report is available in electronic format (pdf) at http://www.nano.hw.ac.uk/research-projects/itsnano.html.CONCLUSION:ITS-NANO has delivered a detailed, stakeholder driven and flexible research prioritisation (or strategy) tool, which identifies specific research needs, suggests connections between areas, and frames this in a time-perspective.

Engineered nanoparticles are increasingly used in medical applications and day-to-day consumer products, leading to concerns about the potential environmental and human health impacts. Silver nanoparticles are particularly prevalent because of their use as anti-bacterial agents in many commonly available products. Nanoparticles (NPs) are believed to accumulate, often preferentially, in the liver. This study therefore investigates the effect of a silver NP (20 nm) on the liver, and in particular, the role of Kupffer cells (KCs; resident liver macrophages) in the overall inflammatory response in the organ. Cytokine expression in the normal liver was measured in terms of IL2, IL4, TNF-α, IFN-γ and IL10 released from the organ with significant up-regulation of TNF-α and IL10 being observed. For livers in which the KC population was specifically targeted and destroyed this cytokine increase was significantly decreased in comparison to the normal tissue. IL10 was secreted at approximately three times the concentration of TNF-α in all the test cases. The high levels of IL10 released from the normal tissue in comparison to the KC depleted livers suggest that the cytokine may help to protect against a pro-inflammatory response to these Ag NPs. This may indicate a potentially important role for KCs in the anti-inflammatory response and suggests that tolerance to the Ag NPs is favoured over a fully activated immune response. In addition, albumin production was measured as an indicator of hepatic function. It was noted that the liver function was unaffected by the Ag NPs.

Historically, it has been challenging to go beyond epidemiology to investigate the pathogenic changes caused by tobacco smoking. The EpiAirway-100 (MatTek Corp., Ashland, MA) was employed to investigate the effects of cigarette smoke components. Exposure at the air-liquid-interface represented particle and vapour phase components of cigarette smoke. A proteomic study utilising iTRAQ labelling compared expression profiles. The correlative histopathology revealed focal regions of hyperplasia, hypertrophy, cytolysis and necrosis. We identified 466 proteins, 250 with a parameter of two or more peptides. Four of these proteins are potential markers of lung injury and three are related to mechanistic pathways of disease.

1. The general term ‘nanoparticle’ (NP) is used to define any particle less than 100 nm in at least one dimension and NPs are generally classified as natural, anthropogenic or engineered in origin. Anthropogenic, also referred to as ‘ultrafine’ particles (UFPs), are predominately combustion derived and are characterized by having an equivalent spherical diameter less than 100 nm. 2. These particles, considered to be ‘combustion-derived nanoparticles’ (CDNPs), are of toxicological interest given their nanosized dimensions, with properties not displayed by their macroscopic counterparts. 3. The pulmonary deposition efficiency of inhaled UFPs, along with their large surface areas and bound transition metals, is considered important in driving the emerging health effects linked to respiratory toxicity. 4. The toxicology of CDNPs is currently used to predict the health outcomes in humans following exposure to manufactured NPs. Their similar physicochemistry would suggest similar adverse health effects (i.e. pulmonary (and perhaps cardiac) toxicity). As such, it is essential to fully understand CDNP nanotoxicology in order to minimize occupational and environmental exposure. Key words: carbon black, combustion-derived particles, diesel exhaust, fly ash, nanoparticles, pulmonary toxicity.

There is strong epidemiological evidence of association between PM10 (particulate matter with an aerodynamic diameter less than or equal to 10 microm) and adverse health outcomes including death and increased hospital admissions for cardiopulmonary conditions. Ambient PM10 surrogates such as diesel exhaust particles (DEP), a common component of UK PM10 have been shown to induce lung inflammation in both humans and rodents. To date, few studies have reported on the toxicological response of UK PM10 in experimental animals. This study examines the pulmonary toxicological responses in male Sprague Dawley rats following the intratracheal instillation of Cardiff urban PM10. A mild but significant change in lung permeability was observed in the lung post-instillation of a high (10 mg) dose of the whole PM10 as adjudged by increases in lung to body weight ratio and total acellular lavage protein. Such effects were less marked following instillation of a water-soluble fraction (80% of the total mass) but histological examination showed that lung capillaries were swollen in size with this treatment. In conclusion, conventional toxicological, histological and toxicogenomic studies have indicated that Cardiff PM10 exhibits low bioreactivity in the form of mild permeability changes. Differential gene expression was observed when the lung was treated with whole PM10, containing durable particles, in comparison with the water-soluble fraction of PM10 that was devoid of particles. Such changes were linked to different histopathological events within the lung.

This study was undertaken primarily to identify genetic markers of oedema and inflammation. Mild pulmonary injury was induced following the instillation of the oedema-producing agent, bleomycin (0.5 units). Oedema was then confirmed by conventional toxicology (lavage protein levels, free cell counts and lung/body weight ratios) and histology 3 days post-bleomycin instillation. The expression profile of 1176 mRNA species was determined for bleomycin-exposed lung (Clontech Atlas macroarray, n=9). To obtain pertinent results from these data, it was necessary to develop a simple, effective method for bioinformatic analysis of altered gene expression. Data were log10 transformed followed by global normalisation. Differential gene expression was accepted if: (a) genes were statistically significant (P < or = 0.05) from a two-tailed t test; (b) genes were consistently outside a two standard deviation (SD) range from control levels. A combination of these techniques identified 31 mRNA transcripts (approximately 3%) which were significantly altered in bleomycin treated tissue. Of these genes, 26 were down-regulated whilst only five were up-regulated. Two distinct clusters were identified, with 17 genes classified as encoding hormone receptors, and nine as encoding ion channels. Both these clusters were consistently down-regulated. The magnitude of the changes in gene expression were quantified and confirmed by Q-PCR (n = 6), validating the macroarray data and the bioinformatic analysis employed. In conclusion, this study has developed a suitable macroarray analysis procedure and provides the basis for a better understanding of the gene expression changes occurring during the early phase of drug-induced pulmonary oedema. This work has been presented orally, in part at the British Association for Lung Research Summer Meeting, University of Brighton, 3-5 September, 2003 and in full at the British Toxicology Society Annual Congress, Heriot Watt University, Edinburgh, 21-24 April 2004.