ABSTRACT
BackgroundCoronavirus (COVID-19) poses health system challenges in every country. As with any public health emergency, a major component of the global response is timely, effective science. However, particular factors specific to COVID-19 must be overcome to ensure that research efforts are optimised. We aimed to model the impact of COVID-19 on the clinical academic response in the UK, and to provide recommendations for COVID-related research. MethodsWe constructed a simple stochastic model to determine clinical academic capacity in the UK in four policy approaches to COVID-19 with differing population infection rates: "Italy model" (6%), "mitigation" (10%), "relaxed mitigation" (40%) and "do-nothing" (80%) scenarios. The ability to conduct research in the COVID-19 climate is affected by the following key factors: (i) infection growth rate and population infection rate (from UK COVID-19 statistics and WHO); (ii) strain on the healthcare system (from published model); and (iii) availability of clinical academic staff with appropriate skillsets affected by frontline clinical activity and sickness (from UK statistics). FindingsIn "Italy model", "mitigation", "relaxed mitigation" and "do-nothing" scenarios, from 5 March 2020 the duration (days) and peak infection rates (%) are 95(2.4%), 115(2.5%), 240(5.3%) and 240(16.7%) respectively. Near complete attrition of academia (87% reduction, <400 clinical academics) occurs 35 days after pandemic start for 11, 34, 62, 76 days respectively - with no clinical academics at all for 37 days in the "do-nothing" scenario. Restoration of normal academic workforce (80% of normal capacity) takes 11,12, 30 and 26 weeks respectively. InterpretationPandemic COVID-19 crushes the science needed at system level. National policies mitigate, but the academic community needs to adapt. We highlight six key strategies: radical prioritisation (eg 3-4 research ideas per institution), deep resourcing, non-standard leadership (repurposing of key non-frontline teams), rationalisation (profoundly simple approaches), careful site selection (eg protected sites with large academic backup) and complete suspension of academic competition with collaborative approaches.
ABSTRACT
O objetivo do estudo foi realizar uma avaliação histomorfométrica dos tecidos formados nos alvéolos de extração de coelhos, preenchidos com dois diferentes tipos de biomateriais, em diferentes períodos de cicatrização. Material e Métodos: foram utlizados 14 coelhos da espécie Nova Zelândia, onde foram extraídos os dois molares do mesmo lado da mandíbula de cada animal. Um alvéolo foi preenchido com osso mineral bovino (Bio-Oss, grupo A) e o outro com uma hidroxiapatita sintética (Alobone poros, grupo B). Após três meses, sete animais foram sacrificados e os outros após seis meses. Em seguida, os espécimes foram preparados para análise histomorfométrica. Resultados: em ambos os grupos foram observados histologicamente um íntimo contato dos biomateriais com o tecido ósseo e a presença de novo tecido ósseo, biomateriais remanescentes, tecido conjuntivo e outros tecidos. Os valores da análise histomorfométrica, de formação do novo tecido ósseo para o grupo A e o grupo B, respectivamente, foram: 28,72% ± 11,81% e 30,69% ± 19,65% no período de três meses, e 23,37% ± 19,02% e 25,78% ± 22,75% no período de seis meses. Foram comparados todos os tecidos formados nos espécimes de três e seis meses entre os grupos A e B, e entre o mesmo grupo nos diferentes períodos de tempo. Não houve diferença estatisticamente signifi cante em nenhuma das comparações. Conclusão: baseado nos resultados, os biomateriais mostraram resultados histológicos e histomorfométricos semelhantes em alvéolos de extração de coelhos...
The aim of this study was to perform an histomorphometric evaluation of tissue formed using the rabbit extraction socket model, with application of two different biomaterials over two different post-surgical follow-up periods. Materials and Methods: fourteen male, New Zealand rabbits were used in this study. Two molars were extracted from the same side of the jaw on each rabbit, having one socket filled with bovine bone mineral (group A) and the other with a synthetic hydroxyapatite (group B). In each group, half of the animals were sacrificed at 3 and 6 months of healing. All samples were prepared for histomorphometric evaluation. Results: in both groups, direct contact of biomaterial with bone tissue was observed, and the presence of new bone, remaining biomaterials, fi brous tissue, and other tissues was demonstrated. Histomorphometric values for new bone tissue formation in groups A and B were 28.72% ± 11.81% and 30.69% ± 19.65%, respectively, at 3 months of healing and 23.37% ± 2.19% and 25.78% ± 22.75%, respectively, at 6 months of healing time. No statistically signifi cant differences were seen for intra and intergroup comparisons at three- and six-month healing periods. Conclusions: these results suggest that the two biomaterials used in this study have similar histologic and histomorphometric results using the rabbit extraction socket model...
