Imaging of 3D tissue-engineered models of oral cancer using 890 and 1300 nm optical coherence tomography

© 2015, Nizhny Novgorod State Medical Academy. All rights reserved. Optical coherence tomography (OCT) generates its primary form of contrast from elastic backscatter. It is now the gold standard technique for retinal screening and is emerging rapidly in cardiovascular research however it remains a research goal to establish it to the same degree in epithelial cancer detection and diagnosis. In this report we compare two different OCT systems: an 890 nm spectrometer-based OCT system with 2.5 µm axial resolution and a 1300 nm swept-source OCT system with 7.5 µm axial resolution to determine the effect of these different OCT parameters on the endogenous backscatter contrast of dysplastic/malignant oral mucosa models relative to normal mucosa models. Tissueengineered oral mucosa models constructed with a dysplastic cell line (DOK), a malignant cell line (Cal27) and normal cell were imaged with both of these OCT platforms and comparisons made with regard to apparent epithelial thickness and the visibility of the epithelium relative to the underlying stroma. For the Cal27’s, hematoxylin and eosin staining confirmed the formation of a keratinized layer superficial to a thickened layer of viable cells on top of the stroma. The keratinized layer presented as a hyperreflective thickened layer superficial to a darker region on both OCT platforms. The keratinized layer caused a steep fall in signal at 890 nm, making it difficult to visualise underlying structures, whereas 1300 nm OCT clearly visualized both the epithelial cells and the stroma lying beneath. For the DOK cells, hematoxylin and eosin staining confirmed the formation of an epithelial layer frequently presenting an abnormal morphology especially at the epidermal/stromal junction, with features such as infiltrating, bulbous rete pegs. These were more clearly visualized under 890 nm OCT. These observations show that 890 nm OCT retains some of its known advantages of higher contrast between anatomical tissue layers when used to observe dysplastic and malignant 3D oral mucosa constructs. However 1300 nm OCT is confirmed to possess a greater ability to image the full thickness of the model epithelia and in particular it is more suited to imaging through the keratinized layer

Evaluating services for perinatal asphyxia and low birth weight at two hospitals in Ghana: a micro-costing analysis

Background: Neonatal mortality has been decreasing slowly in Ghana despite investments in maternal-newborn services. Although community-based interventions are effective in reducing newborn deaths, hospital-based services provide better health outcomes.Objective: To examine the process and cost of hospital-based services for perinatal asphyxia and low birth weight/preterm at a district and a regional level referral hospital in Ghana.Methods: A cross-sectional study was conducted at 2 hospitals in Greater Accra Region during May-July 2016. Term infants with perinatal asphyxia and low birth weight/preterm infants referred for special care within 24hours after birth were eligible. Time-driven activity-based costing (TDABC) approach was used to examine the process and cost of all activities in the full cycle of care from admission until discharge or death. Costs were analysed from health provider’s perspective.Results: Sixty-two newborns (perinatal asphyxia 27, low-birth-weight/preterm 35) were enrolled. Cost of care was proportionately related to length-of-stay. Personnel costs constituted over 95% of direct costs, and all resources including personnel, equipment and supplies were overstretched.Conclusion: TDABC analysis revealed gaps in the organization, process and financing of neonatal services that undermined the quality of care for hospitalized newborns. The study provides baseline cost data for future cost-effectiveness studies on neonatal services in Ghana.Keywords: perinatal asphyxia; low-birth-weight; time-driven activity-based costing; process of careFunding: Authors received no external funding for the stud

Establishing a versatile toolkit of flux enhanced strains and cell extracts for pathway prototyping

Building and optimizing biosynthetic pathways in engineered cells holds promise to address societal needs in energy, materials, and medicine, but it is often time-consuming. Cell-free synthetic biology has emerged as a powerful tool to accelerate design-build-test-learn cycles for pathway engineering with increased tolerance to toxic compounds. However, most cell-free pathway prototyping to date has been performed in extracts from wildtype cells which often do not have sufficient flux towards the pathways of interest, which can be enhanced by engineering. Here, to address this gap, we create a set of engineered Escherichia coli and Saccharomyces cerevisiae strains rewired via CRISPR-dCas9 to achieve high-flux toward key metabolic precursors; namely, acetyl-CoA, shikimate, triose-phosphate, oxaloacetate, α-ketoglutarate, and glucose-6-phosphate. Cell-free extracts generated from these strains are used for targeted enzyme screening in vitro. As model systems, we assess in vivo and in vitro production of triacetic acid lactone from acetyl-CoA and muconic acid from the shikimate pathway. The need for these platforms is exemplified by the fact that muconic acid cannot be detected in wildtype extracts provided with the same biosynthetic enzymes. We also perform metabolomic comparison to understand biochemical differences between the cellular and cell-free muconic acid synthesis systems (E. coli and S. cerevisiae cells and cell extracts with and without metabolic rewiring). While any given pathway has different interfaces with metabolism, we anticipate that this set of pre-optimized, flux enhanced cell extracts will enable prototyping efforts for new biosynthetic pathways and the discovery of biochemical functions of enzymes

Trends in greenhouse gas emissions from dairy cattle in Mexico between 1970 and 2010

The objective of the present work was to estimate and assess trends in greenhouse gas (GHG) emissions, particularly methane (CH4) and nitrous oxide (N2O), from dairy cows in Mexico from the base year of 1970 to 2010. Empirical and mechanistic models were used to estimate enteric methane emissions based on chemical composition of diets. Methane from manure was calculated using Intergovernmental Panel for Climate Change (IPCC) and US Environmental Protection Agency recommended equations. N2O emission was calculated according to IPCC recommendations. Compared with the 1970s, current management practices using modern dairy cows increased feed conversion efficiency 32% and milk yield 62%. GHG emission intensity (i.e. emissions per unit of product) was reduced 30%, 25% and 30% for CH4, N2O and total emissions, respectively. The study showed that although GHG emissions in absolute terms increased in the past 40 years, emission intensity decreased due to higher level of production. This trend is likely to continue in the future, assuming milk production follows the same increasing trend as in other countries in North America. © 2014 CSIRO

Predicting attitudinal and behavioral responses to COVID-19 pandemic using machine learning

At the beginning of 2020, COVID-19 became a global problem. Despite all the efforts to emphasize the relevance of preventive measures, not everyone adhered to them. Thus, learning more about the characteristics determining attitudinal and behavioral responses to the pandemic is crucial to improving future interventions. In this study, we applied machine learning on the multi-national data collected by the International Collaboration on the Social and Moral Psychology of COVID-19 (N = 51,404) to test the predictive efficacy of constructs from social, moral, cognitive, and personality psychology, as well as socio-demographic factors, in the attitudinal and behavioral responses to the pandemic. The results point to several valuable insights. Internalized moral identity provided the most consistent predictive contribution—individuals perceiving moral traits as central to their self-concept reported higher adherence to preventive measures. Similar was found for morality as cooperation, symbolized moral identity, self-control, open-mindedness, collective narcissism, while the inverse relationship was evident for the endorsement of conspiracy theories. However, we also found a non-negligible variability in the explained variance and predictive contributions with respect to macro-level factors such as the pandemic stage or cultural region. Overall, the results underscore the importance of morality-related and contextual factors in understanding adherence to public health recommendations during the pandemic.Peer reviewe

National identity predicts public health support during a global pandemic.

Changing collective behaviour and supporting non-pharmaceutical interventions is an important component in mitigating virus transmission during a pandemic. In a large international collaboration (Study 1, N = 49,968 across 67 countries), we investigated self-reported factors associated with public health behaviours (e.g., spatial distancing and stricter hygiene) and endorsed public policy interventions (e.g., closing bars and restaurants) during the early stage of the COVID-19 pandemic (April-May 2020). Respondents who reported identifying more strongly with their nation consistently reported greater engagement in public health behaviours and support for public health policies. Results were similar for representative and non-representative national samples. Study 2 (N = 42 countries) conceptually replicated the central finding using aggregate indices of national identity (obtained using the World Values Survey) and a measure of actual behaviour change during the pandemic (obtained from Google mobility reports). Higher levels of national identification prior to the pandemic predicted lower mobility during the early stage of the pandemic (r = -0.40). We discuss the potential implications of links between national identity, leadership, and public health for managing COVID-19 and future pandemics

National identity predicts public health support during a global pandemic (vol 13, 517, 2022) : National identity predicts public health support during a global pandemic (Nature Communications, (2022), 13, 1, (517), 10.1038/s41467-021-27668-9)

Publisher Copyright: © The Author(s) 2022.In this article the author name ‘Agustin Ibanez’ was incorrectly written as ‘Augustin Ibanez’. The original article has been corrected.Peer reviewe