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101.
Danail Hristozov Alex Zabeo Keld Alstrup Jensen Stefania Gottardo Panagiotis Isigonis Laura Maccalman 《Nanotoxicology》2016,10(9):1215-1228
Several tools to facilitate the risk assessment and management of manufactured nanomaterials (MN) have been developed. Most of them require input data on physicochemical properties, toxicity and scenario-specific exposure information. However, such data are yet not readily available, and tools that can handle data gaps in a structured way to ensure transparent risk analysis for industrial and regulatory decision making are needed. This paper proposes such a quantitative risk prioritisation tool, based on a multi-criteria decision analysis algorithm, which combines advanced exposure and dose-response modelling to calculate margins of exposure (MoE) for a number of MN in order to rank their occupational risks. We demonstrated the tool in a number of workplace exposure scenarios (ES) involving the production and handling of nanoscale titanium dioxide, zinc oxide (ZnO), silver and multi-walled carbon nanotubes. The results of this application demonstrated that bag/bin filling, manual un/loading and dumping of large amounts of dry powders led to high emissions, which resulted in high risk associated with these ES. The ZnO MN revealed considerable hazard potential in vivo, which significantly influenced the risk prioritisation results. In order to study how variations in the input data affect our results, we performed probabilistic Monte Carlo sensitivity/uncertainty analysis, which demonstrated that the performance of the proposed model is stable against changes in the exposure and hazard input variables. 相似文献
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《Vaccine》2016,34(24):2663-2670
Human metapneumovirus (HMPV) is a major cause of morbidity and mortality from acute lower respiratory tract illness, with most individuals seropositive by age five. Despite the presence of neutralizing antibodies, secondary infections are common and can be severe in young, elderly, and immunocompromised persons. Preclinical vaccine studies for HMPV have suggested a need for a balanced antibody and T cell immune response to enhance protection and avoid lung immunopathology. We infected transgenic mice expressing human HLA-A*0201 with HMPV and used ELISPOT to screen overlapping and predicted epitope peptides. We identified six novel HLA-A2 restricted CD8+ T cell (TCD8) epitopes, with M39–47 (M39) immunodominant. Tetramer staining detected M39-specific TCD8 in lungs and spleen of HMPV-immune mice. Immunization with adjuvant-formulated M39 peptide reduced lung virus titers upon challenge. Finally, we show that TCD8 from HLA-A*0201 positive humans recognize M39 by IFNγ ELISPOT and tetramer staining. These results will facilitate HMPV vaccine development and human studies. 相似文献
104.
Christos Loizou Göran Laurell Andreas Arvidsson David Lindquist Karin Nylander Katarina Olofsson 《Acta oto-laryngologica》2015,135(10):1058-1064
Conclusion: Recurrent respiratory papillomatosis (RRP) patients with high surgical treatment frequency (≥ 1/year, HF) were significantly younger and had a more widespread laryngeal disease compared to a low frequency treated group (< 1 treatment/year, LF). This study confirms the existence of a clinical RRP group, not primarily related to HPV sub-type, but more care-intensive and in need of more vigilant follow-up. Objectives: RRP is associated with high morbidity due to its influence on breathing and voice. The purpose of this study was to characterize RRP patients in northern Sweden and investigate possible predictor factors affecting therapeutic needs. Method: Patients from the regional referral area (northern Sweden) were categorized for age, disease duration, juvenile or adult onset, profile of disease development, number of surgical sessions in relation to disease duration, laryngeal deposition of papilloma, gender, and HPV sub-types, in order to identify patients with increased need for frequent surgical treatment. Results: The median age of the RRP patients (n = 48) was 44.5 years; 34 (71%) were males and 14 (29%) females, most were infected with HPV 6. Patients with high surgical treatment frequency/year were significantly younger and showed more widespread papillomatous vegetation in the larynx, compared to the low frequency treated group. 相似文献
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Nyika Machenjedze Macalane J Malindi Fungai Mbengo 《African Journal of AIDS Research》2019,18(1):72-80
Worldwide, researchers routinely study children indirectly through adults who act as proxies for such children. The call for researchers to rather study children directly and adopt less intrusive child-friendly methodologies has become louder. The draw-and-write technique is regarded as a less intrusive child-friendly method of collecting data that can be used for this purpose. This paper reports the findings of a qualitative study that sought to establish the feasibility of the draw-and-write technique in exploring the resilience of children orphaned by AIDS. This study involved a convenience sample of 23 IsiXhosa-speaking orphaned children aged from 13 to 17. The participants were in grades 6 to 10 and they resided in two child and youth care centres in the Eastern Cape province of South Africa. As part of the draw-and-write technique the participants were asked to make drawings of what enabled them to cope with their lives and to write short narratives in which they explained their drawings. Inductive content analysis was used to analyse the data and this process yielded two main themes, namely: personal protective resources and socio-ecological protective resources. The findings show that complex combinations of personal and socio-ecological resilience resources enabled the resilience of the orphaned children. The findings challenge researchers not to be oblivious to alternative child-friendly methods of research such as the draw-and-write technique when young people are the unit of analysis. The findings of this study have implications for research as well as practice in the field of education and psychology. 相似文献
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AbstractThis article follows up a pilot project to help educate local nurses and patient educators on freely available consumer health resources. The Outreach Coordinator and Clinical Librarian at an academic medical center created a one-hour in-person and online class with continuing education credit and an online guide. Nurses frequently act as patient educators at the bedside and are therefore an important target for consumer health education. While nurses in an urban setting may have more access to educational opportunities, these opportunities are needed even more in rural settings. Librarians can obtain funding to travel and teach classes at rural community hospitals. 相似文献