Modelling upper respiratory viral load dynamics of SARS-CoV-2.

Relationships between viral load, severity of illness, and transmissibility of virus are fundamental to understanding pathogenesis and devising better therapeutic and prevention strategies for COVID-19. Here we present within-host modelling of viral load dynamics observed in the upper respiratory tract (URT), drawing upon 2172 serial measurements from 605 subjects, collected from 17 different studies. We developed a mechanistic model to describe viral load dynamics and host response and contrast this with simpler mixed-effects regression analysis of peak viral load and its subsequent decline. We observed wide variation in URT viral load between individuals, over 5 orders of magnitude, at any given point in time since symptom onset. This variation was not explained by age, sex, or severity of illness, and these variables were not associated with the modelled early or late phases of immune-mediated control of viral load. We explored the application of the mechanistic model to identify measured immune responses associated with the control of the viral load. Neutralising antibodies correlated strongly with modelled immune-mediated control of viral load amongst subjects who produced neutralising antibodies. Our models can be used to identify host and viral factors which control URT viral load dynamics, informing future treatment and transmission blocking interventions

Prognostic model to predict postoperative acute kidney injury in patients undergoing major gastrointestinal surgery based on a national prospective observational cohort study.

Background: Acute illness, existing co-morbidities and surgical stress response can all contribute to postoperative acute kidney injury (AKI) in patients undergoing major gastrointestinal surgery. The aim of this study was prospectively to develop a pragmatic prognostic model to stratify patients according to risk of developing AKI after major gastrointestinal surgery. Methods: This prospective multicentre cohort study included consecutive adults undergoing elective or emergency gastrointestinal resection, liver resection or stoma reversal in 2-week blocks over a continuous 3-month period. The primary outcome was the rate of AKI within 7 days of surgery. Bootstrap stability was used to select clinically plausible risk factors into the model. Internal model validation was carried out by bootstrap validation. Results: A total of 4544 patients were included across 173 centres in the UK and Ireland. The overall rate of AKI was 14·2 per cent (646 of 4544) and the 30-day mortality rate was 1·8 per cent (84 of 4544). Stage 1 AKI was significantly associated with 30-day mortality (unadjusted odds ratio 7·61, 95 per cent c.i. 4·49 to 12·90; P < 0·001), with increasing odds of death with each AKI stage. Six variables were selected for inclusion in the prognostic model: age, sex, ASA grade, preoperative estimated glomerular filtration rate, planned open surgery and preoperative use of either an angiotensin-converting enzyme inhibitor or an angiotensin receptor blocker. Internal validation demonstrated good model discrimination (c-statistic 0·65). Discussion: Following major gastrointestinal surgery, AKI occurred in one in seven patients. This preoperative prognostic model identified patients at high risk of postoperative AKI. Validation in an independent data set is required to ensure generalizability

Exploring the Effects of Monomer and Polymer Cosolutes on the Conformation of Escherichia coli Prolyl-tRNA Synthetase Using Intrinsic Tryptophan Fluorescence Spectroscopy

Color poster with text, images, charts, and graphs.National Institute of Health (Grant #:1R15GM117510-0); University of Wisconsin--Eau Claire Office of Research and Sponsored Program

A Continuing Examination of Food Purchasing through the Supplemental Nutrition Assistance Program (SNAP) and the Women, Infants and Children Program (WIC) : A Case Study of Grocery Stores and Farmers’ Markets with an Emphasis on Fruits and Vegetables II

Color poster with text, images, charts, photographs, and graphs.Research suggests that food insecurity is a significant issue facing many American families with nearly one in five children living in a food insecure household. Many Americans also suffer from poor nutrition and specifically fall short of eating the recommended number of fruits and vegetables (FV). Additionally, as a country we are still facing high rates of obesity especially for children with both poor nutrition and obesity disproportionately affecting low-income households. There is also evidence that participants in government assistance programs designed to provide food assistance such as the Supplemental Nutrition Assistance Program (SNAP) and the Women, Infants and Children Program (WIC) tend to purchase fewer healthy foods including FV compared to the overall population. One way to address this issue is to connect these families to farmers’ markets in their area and encourage healthier shopping and eating behaviors. The Eau Claire Farmers’ Market –Market Match Program (EC FM MMP) doubles SNAP benefits up to $10/week at the EC FM to provide an incentive for SNAP households to shop at the market. Similarly, the WIC FV Farmers’ Market Program (WIC FV FMP) is designed to help improve access to FV for qualifying households during the summer. This study reports on 2014-19 administrative data and 2019 survey data from for the EC FM MMP as well as 2019 administrative data for the WIC FV FMP in the state of Wisconsin. We also have data for a FV FM program helping low-income senior citizens access FV at FM and will present briefly on these data. Our complete work is presented over two postersUniversity of Wisconsin--Eau Claire Office of Research and Sponsored Program