55 research outputs found
Developing a tooth in situ organ culture model for dental and periodontal regeneration research
In this study we have realized the need for an organ culture tooth in situ model to simulate the tooth structure especially the tooth attachment apparatus. The importance of such a model is to open avenues for investigating regeneration of the complex tooth and tooth attachment tissues and to reduce the need for experimental animals in investigating dental materials and treatments in the future. The aim of this study was to develop a porcine tooth in situ organ culture model and a novel bioreactor suitable for future studies of periodontal regeneration, including application of appropriate physiological loading. The Objectives of this study was to establish tissue viability, maintenance of tissue structure, and model sterility after 1 and 4 days of culture. To model diffusion characteristics within the organ culture system and design and develop a bioreactor that allows tooth loading and simulation of the chewing cycle. Methods: Twenty-one porcine first molars were dissected aseptically in situ within their bony sockets. Twelve were used to optimize sterility and determine tissue viability. The remainder were used in a 4-day organ culture study in basal medium. Sterility was determined for medium samples and swabs taken from all tissue components, using standard aerobic and anaerobic microbiological cultures. Tissue viability was determined at days 1 and 4 using an XTT assay and Glucose consumption assays. Maintenance of structure was confirmed using histology and histomorphometric analysis. Diffusion characteristics were investigated using micro-CT combined with finite element modeling. A suitable bioreactor was designed to permit longer term culture with application of mechanical loading to the tooth in situ. Result: XTT and Glucose consumption assays confirmed viability throughout the culture period for all tissues investigated. Histological and histomorphometric analysis confirmed maintenance of tissue structure. Clear microbiological cultures indicated maintenance of sterility within the organ culture system. The novel bioreactor showed no evidence of medium contamination after 4 days of culture. Finite element modeling indicated nutrient availability to the periodontium. Conclusion: A whole tooth in situ organ culture system was successfully maintained over 4 days in vitro
Pre-diagnostic circulating insulin-like growth factor-I and bladder cancer risk in the European Prospective Investigation into Cancer and Nutrition
Previous in vitro and case–control studies have found an association between the insulin‐like growth factor (IGF)‐axis and bladder cancer risk. Circulating concentrations of IGF‐I have also been found to be associated with an increased risk of several cancer types; however, the relationship between pre‐diagnostic circulating IGF‐I concentrations and bladder cancer has never been studied prospectively. We investigated the association of pre‐diagnostic plasma concentrations of IGF‐I with risk of overall bladder cancer and urothelial cell carcinoma (UCC) in a case–control study nested within the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort. A total of 843 men and women diagnosed with bladder cancer between 1992 and 2005 were matched with 843 controls by recruitment centre, sex, age at recruitment, date of blood collection, duration of follow‐up, time of day and fasting status at blood collection using an incidence density sampling protocol. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated using conditional logistic regression with adjustment for smoking status. No association was found between pre‐diagnostic circulating IGF‐I concentration and overall bladder cancer risk (adjusted OR for highest versus lowest fourth: 0.91, 95% CI: 0.66–1.24, ptrend = 0.40) or UCC (n of cases = 776; 0.91, 0.65–1.26, ptrend = 0.40). There was no significant evidence of heterogeneity in the association of IGF‐I with bladder cancer risk by tumour aggressiveness, sex, smoking status, or by time between blood collection and diagnosis (pheterogeneity > 0.05 for all). This first prospective study indicates no evidence of an association between plasma IGF‐I concentrations and bladder cancer risk
Prediagnostic circulating concentrations of plasma insulin-like growth factor-I and risk of lymphoma in the European Prospective Investigation into Cancer and Nutrition
Insulin-like growth factor (IGF)-I has cancer promoting activities. However, the hypothesis that circulating IGF-I concentration is related to risk of lymphoma overall or its subtypes has not been examined prospectively. IGF-I concentration was measured in pre-diagnostic plasma samples from a nested case-control study of 1,072 cases of lymphoid malignancies and 1,072 individually matched controls from the European Prospective Investigation into Cancer and Nutrition. Odds ratios (ORs) and confidence intervals (CIs) for lymphoma were calculated using conditional logistic regression. IGF-I concentration was not associated with overall lymphoma risk (multivariable-adjusted OR for highest versus lowest third = 0.77 [95% CI = 0.57-1.03], ptrend = 0.06). There was no statistical evidence of heterogeneity in this association with IGF-I by sex, age at blood collection, time between blood collection and diagnosis, age at diagnosis, or body mass index (pheterogeneity for all ≥ 0.05). There were no associations between IGF-I concentration and risk for specific BCL subtypes, T-cell lymphoma or Hodgkin lymphoma, although number of cases were small. In this European population, IGF-I concentration was not associated with risk of overall lymphoma. This study provides the first prospective evidence on circulating IGF-I concentrations and risk of lymphoma. Further prospective data are required to examine associations of IGF-I concentrations with lymphoma subtypes.The coordination of EPIC is financially supported by the European Commission (DG-SANCO) and the International Agency for Research on Cancer. The national cohorts are supported by Danish Cancer Society (Denmark); Ligue Contre le Cancer, Institut Gustave Roussy, Mutuelle Générale de l’Education Nationale, Institut National de la Santé et de la Recherche Médicale (INSERM) (France); German Cancer Aid, German Cancer Research Center (DKFZ), Federal Ministry of Education and Research (BMBF), Deutsche Krebshilfe, Deutsches Krebsforschungszentrum and Federal Ministry of Education and Research (Germany); the Hellenic Health Foundation (Greece); Associazione Italiana per la Ricerca sul Cancro-AIRC-Italy and National Research Council (Italy); Dutch Ministry of Public Health, Welfare and Sports (VWS), Netherlands Cancer Registry (NKR), LK Research Funds, Dutch Prevention Funds, Dutch ZON (Zorg Onderzoek Nederland), World Cancer Research Fund (WCRF), Statistics Netherlands (The Netherlands); ERC-2009-AdG 232997 and Nordforsk, Nordic Centre of Excellence programme on Food, Nutrition and Health (Norway); Health Research Fund (FIS), PI13/00061 to Granada, PI13/01162 to EPIC-Murcia, Regional Governments of Andalucía, Asturias, Basque Country, Murcia and Navarra, ISCIII RETIC (RD06/0020) (Spain); Swedish Cancer Society, Swedish Research Council and County Councils of Skåne and Västerbotten (Sweden); Cancer Research UK (14136 to EPIC-Norfolk; C570/A11692, C570/A16491 and C8221/A19170 to EPIC-Oxford), Medical Research Council (1000143 to EPIC-Norfolk, MR/M012190/1 to EPIC-Oxford) (United Kingdom)
Circulating insulin-like growth factor I in relation to melanoma risk in the European Prospective Investigation into Cancer and Nutrition
Insulin-like growth factor-I (IGF-I) regulates cell proliferation and apoptosis, and is thought to play a role in tumour development. Previous prospective studies have shown that higher circulating concentrations of IGF-I are associated with a higher risk of cancers at specific sites, including breast and prostate. No prospective study has examined the association between circulating IGF-I concentrations and melanoma risk. A nested case-control study of 1,221 melanoma cases and 1,221 controls was performed in the European Prospective Investigation into Cancer and Nutrition cohort, a prospective cohort of 520,000 participants recruited from 10 European countries. Conditional logistic regression was used to estimate odds ratios (ORs) for incident melanoma in relation to circulating IGF-I concentrations, measured by immunoassay. Analyses were conditioned on the matching factors and further adjusted for age at blood collection, education, height, BMI, smoking status, alcohol intake, marital status, physical activity and in women only, use of menopausal hormone therapy. There was no significant association between circulating IGF-I concentration and melanoma risk (OR for highest vs lowest fifth = 0.93 [95% confidence interval [CI]: 0.71 to 1.22]). There was no significant heterogeneity in the association between IGF-I concentrations and melanoma risk when subdivided by gender, age at blood collection, BMI, height, age at diagnosis, time between blood collection and diagnosis, or by anatomical site or histological subtype of the tumour (Pheterogeneity≥0.078). We found no evidence for an association between circulating concentrations of IGF-I measured in adulthood and the risk of melanoma
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How to specify healthcare process improvements collaboratively using rapid, remote consensus-building: a framework and a case study of its application
Abstract: Background: Practical methods for facilitating process improvement are needed to support high quality, safe care. How best to specify (identify and define) process improvements – the changes that need to be made in a healthcare process – remains a key question. Methods for doing so collaboratively, rapidly and remotely offer much potential, but are under-developed. We propose an approach for engaging diverse stakeholders remotely in a consensus-building exercise to help specify improvements in a healthcare process, and we illustrate the approach in a case study. Methods: Organised in a five-step framework, our proposed approach is informed by a participatory ethos, crowdsourcing and consensus-building methods: (1) define scope and objective of the process improvement; (2) produce a draft or prototype of the proposed process improvement specification; (3) identify participant recruitment strategy; (4) design and conduct a remote consensus-building exercise; (5) produce a final specification of the process improvement in light of learning from the exercise. We tested the approach in a case study that sought to specify process improvements for the management of obstetric emergencies during the COVID-19 pandemic. We used a brief video showing a process for managing a post-partum haemorrhage in women with COVID-19 to elicit recommendations on how the process could be improved. Two Delphi rounds were then conducted to reach consensus. Results: We gathered views from 105 participants, with a background in maternity care (n = 36), infection prevention and control (n = 17), or human factors (n = 52). The participants initially generated 818 recommendations for how to improve the process illustrated in the video, which we synthesised into a set of 22 recommendations. The consensus-building exercise yielded a final set of 16 recommendations. These were used to inform the specification of process improvements for managing the obstetric emergency and develop supporting resources, including an updated video. Conclusions: The proposed methodological approach enabled the expertise and ingenuity of diverse stakeholders to be captured and mobilised to specify process improvements in an area of pressing service need. This approach has the potential to address current challenges in process improvement, but will require further evaluation
Pre-diagnostic circulating insulin-like growth factor-I and bladder cancer risk in the European Prospective Investigation into Cancer and Nutrition
Previous in vitro and case-control studies have found an association between the insulin-like growth factor (IGF)-axis and bladder cancer risk. Circulating concentrations of IGF-I have also been found to be associated with an increased risk of several cancer types; however, the relationship between pre-diagnostic circulating IGF-I concentrations and bladder cancer has never been studied prospectively. We investigated the association of pre-diagnostic plasma concentrations of IGF-I with risk of overall bladder cancer and urothelial cell carcinoma (UCC) in a case-control study nested within the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort. A total of 843 men and women diagnosed with bladder cancer between 1992 and 2005 were matched with 843 controls by recruitment centre, sex, age at recruitment, date of blood collection, duration of follow-up, time of day and fasting status at blood collection using an incidence density sampling protocol. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated using conditional logistic regression with adjustment for smoking status. No association was found between pre-diagnostic circulating IGF-I concentration and overall bladder cancer risk (adjusted OR for highest versus lowest fourth: 0.91, 95% CI: 0.66-1.24, ptrend = 0.40) or UCC (n of cases = 776; 0.91, 0.65-1.26, ptrend = 0.40). There was no significant evidence of heterogeneity in the association of IGF-I with bladder cancer risk by tumour aggressiveness, sex, smoking status, or by time between blood collection and diagnosis (pheterogeneity > 0.05 for all). This first prospective study indicates no evidence of an association between plasma IGF-I concentrations and bladder cancer risk
Point-of-care testing in paediatric settings in the UK and Ireland: A cross-sectional study
Background: Point-of-care testing (POCT) is diagnostic testing performed at or near to the site of the patient. Understanding the current capacity, and scope, of POCT in this setting is essential in order to respond to new research evidence which may lead to wide implementation. Methods: A cross-sectional online survey study of POCT use was conducted between 6th January and 2nd February 2020 on behalf of two United Kingdom (UK) and Ireland-based paediatric research networks (Paediatric Emergency Research UK and Ireland, and General and Adolescent Paediatric Research UK and Ireland). Results: In total 91/109 (83.5%) sites responded, with some respondents providing details for multiple units on their site based on network membership (139 units in total). The most commonly performed POCT were blood sugar (137/139; 98.6%), urinalysis (134/139; 96.4%) and blood gas analysis (132/139; 95%). The use of POCT for Influenza/Respiratory Syncytial Virus (RSV) (45/139; 32.4%, 41/139; 29.5%), C-Reactive Protein (CRP) (13/139; 9.4%), Procalcitonin (PCT) (2/139; 1.4%) and Group A Streptococcus (5/139; 3.6%) and was relatively low. Obstacles to the introduction of new POCT included resources and infrastructure to support test performance and quality assurance. Conclusion: This survey demonstrates significant consensus in POCT practice in the UK and Ireland but highlights specific inequity in newer biomarkers, some which do not have support from national guidance. A clear strategy to overcome the key obstacles of funding, evidence base, and standardising variation will be essential if there is a drive toward increasing implementation of POCT
Pregnancy and neonatal outcomes of COVID-19: The PAN-COVID study
Objective
To assess perinatal outcomes for pregnancies affected by suspected or confirmed SARS-CoV-2 infection.
Methods
Prospective, web-based registry. Pregnant women were invited to participate if they had suspected or confirmed SARS-CoV-2 infection between 1st January 2020 and 31st March 2021 to assess the impact of infection on maternal and perinatal outcomes including miscarriage, stillbirth, fetal growth restriction, pre-term birth and transmission to the infant.
Results
Between April 2020 and March 2021, the study recruited 8239 participants who had suspected or confirmed SARs-CoV-2 infection episodes in pregnancy between January 2020 and March 2021.
Maternal death affected 14/8197 (0.2%) participants, 176/8187 (2.2%) of participants required ventilatory support. Pre-eclampsia affected 389/8189 (4.8%) participants, eclampsia was reported in 40/ 8024 (0.5%) of all participants.
Stillbirth affected 35/8187 (0.4 %) participants. In participants delivering within 2 weeks of delivery 21/2686 (0.8 %) were affected by stillbirth compared with 8/4596 (0.2 %) delivering ≥ 2 weeks after infection (95 % CI 0.3–1.0). SGA affected 744/7696 (9.3 %) of livebirths, FGR affected 360/8175 (4.4 %) of all pregnancies.
Pre-term birth occurred in 922/8066 (11.5%), the majority of these were indicated pre-term births, 220/7987 (2.8%) participants experienced spontaneous pre-term births. Early neonatal deaths affected 11/8050 livebirths. Of all neonates, 80/7993 (1.0%) tested positive for SARS-CoV-2.
Conclusions
Infection was associated with indicated pre-term birth, most commonly for fetal compromise. The overall proportions of women affected by SGA and FGR were not higher than expected, however there was the proportion affected by stillbirth in participants delivering within 2 weeks of infection was significantly higher than those delivering ≥ 2 weeks after infection. We suggest that clinicians’ threshold for delivery should be low if there are concerns with fetal movements or fetal heart rate monitoring in the time around infection
Winds of Change: A Historical Analysis of Hurricanes and Their Impacts, and a System of Assessing the Vulnerability of the Communities They Hit
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