Hedonic bull pricing models: estimating the value of traits of bulls sold following performance testing

Master of AgribusinessDepartment of Agricultural EconomicsTed SchroederSelection of a herd sire has always been of paramount importance given the initial financial investment and their contribution and effect on the genetic make-up of a beef herd. Data was collected from the nation’s longest consecutively run bull test conducted at the University Farm of Oklahoma Panhandle State University (OPSU). The Bull Test and Bull Sale data utilized were collected from 2008-2013. Performance data was collected over a 112 day test period with data collection occurring at 28 day intervals. The top seventy bulls from each year’s test were selected based upon a performance index of ½ ADG and ½ weight per day of age (WDA), and a semen quality and motility score of excellent and sold at auction. Angus bulls were the focus of the study as they represented the vast majority of individuals sold. Three hedonic pricing models were created to try to determine what attributes buyers at the OPSU bull test sale were placing emphasis on. The initial hedonic model contained production data that included BW, ADG, WDA, Julian age, final test weight ultrasound data, and a dummy variable for sale year. The second model utilized all production data and added genetic variables in the form of production EPDs (Calving Ease Direct (CED), BW, Weaning Weight and Yearling Weight) and maternal EPDs (Calving Ease Maternal, Maternal Milk). The third model included the variables from the first and second models with the inclusion of carcass EPDs (Marbling, Ribeye Area (REA) and FAT). Year was significant in all three models however there was less of an effect on price as more variables were included. In model one, the production facts that were of significance were: ADG (P<0.01), BW (P<0.01) and final test weight (P<0.01). In the second model, ADG, BW and final test weight retained their significance at the P<0.01 level. The only production EPD that was significant (P<0.05) was CED. In the third model, years, ADG and BW were still significant (P<0.01). Final test weight (P=0.70) and CED (P = 0.132) had substantial changes. The carcass EPD ribeye area had a P value of 0.057. Producers who are placing bulls on test can utilize the given information to assist with their selection. It cannot go unsaid that while single trait selection can be very detrimental; ADG was significant across all models. The study indicates that performance and growth are of utmost importance to buyers, followed by birth weight consideration

Effectiveness of a national quality improvement programme to improve survival after emergency abdominal surgery (EPOCH): a stepped-wedge cluster-randomised trial

BACKGROUND: Emergency abdominal surgery is associated with poor patient outcomes. We studied the effectiveness of a national quality improvement (QI) programme to implement a care pathway to improve survival for these patients. METHODS: We did a stepped-wedge cluster-randomised trial of patients aged 40 years or older undergoing emergency open major abdominal surgery. Eligible UK National Health Service (NHS) hospitals (those that had an emergency general surgical service, a substantial volume of emergency abdominal surgery cases, and contributed data to the National Emergency Laparotomy Audit) were organised into 15 geographical clusters and commenced the QI programme in a random order, based on a computer-generated random sequence, over an 85-week period with one geographical cluster commencing the intervention every 5 weeks from the second to the 16th time period. Patients were masked to the study group, but it was not possible to mask hospital staff or investigators. The primary outcome measure was mortality within 90 days of surgery. Analyses were done on an intention-to-treat basis. This study is registered with the ISRCTN registry, number ISRCTN80682973. FINDINGS: Treatment took place between March 3, 2014, and Oct 19, 2015. 22 754 patients were assessed for elegibility. Of 15 873 eligible patients from 93 NHS hospitals, primary outcome data were analysed for 8482 patients in the usual care group and 7374 in the QI group. Eight patients in the usual care group and nine patients in the QI group were not included in the analysis because of missing primary outcome data. The primary outcome of 90-day mortality occurred in 1210 (16%) patients in the QI group compared with 1393 (16%) patients in the usual care group (HR 1·11, 0·96-1·28). INTERPRETATION: No survival benefit was observed from this QI programme to implement a care pathway for patients undergoing emergency abdominal surgery. Future QI programmes should ensure that teams have both the time and resources needed to improve patient care. FUNDING: National Institute for Health Research Health Services and Delivery Research Programme

Effectiveness of a national quality improvement programme to improve survival after emergency abdominal surgery (EPOCH): a stepped-wedge cluster-randomised trial

Background: Emergency abdominal surgery is associated with poor patient outcomes. We studied the effectiveness of a national quality improvement (QI) programme to implement a care pathway to improve survival for these patients. Methods: We did a stepped-wedge cluster-randomised trial of patients aged 40 years or older undergoing emergency open major abdominal surgery. Eligible UK National Health Service (NHS) hospitals (those that had an emergency general surgical service, a substantial volume of emergency abdominal surgery cases, and contributed data to the National Emergency Laparotomy Audit) were organised into 15 geographical clusters and commenced the QI programme in a random order, based on a computer-generated random sequence, over an 85-week period with one geographical cluster commencing the intervention every 5 weeks from the second to the 16th time period. Patients were masked to the study group, but it was not possible to mask hospital staff or investigators. The primary outcome measure was mortality within 90 days of surgery. Analyses were done on an intention-to-treat basis. This study is registered with the ISRCTN registry, number ISRCTN80682973. Findings: Treatment took place between March 3, 2014, and Oct 19, 2015. 22 754 patients were assessed for elegibility. Of 15 873 eligible patients from 93 NHS hospitals, primary outcome data were analysed for 8482 patients in the usual care group and 7374 in the QI group. Eight patients in the usual care group and nine patients in the QI group were not included in the analysis because of missing primary outcome data. The primary outcome of 90-day mortality occurred in 1210 (16%) patients in the QI group compared with 1393 (16%) patients in the usual care group (HR 1·11, 0·96–1·28). Interpretation: No survival benefit was observed from this QI programme to implement a care pathway for patients undergoing emergency abdominal surgery. Future QI programmes should ensure that teams have both the time and resources needed to improve patient care. Funding: National Institute for Health Research Health Services and Delivery Research Programme

Lipidomics analysis of essential fatty acids in macrophages.

The Lipid Metabolites and Pathway Strategy (LIPID MAPS) Consortium is a nationwide initiative that has taken on the task of employing lipidomics to advance our understanding of lipid metabolism at the molecular and mechanistic level in living organisms. An important step toward this goal is to craft enabling analytical procedures to comprehensively measure all lipid species, to establish the precise structural identity of the lipid molecules analyzed, and to generate accurate quantitative information. The LIPID MAPS Consortium has succeeded in the implementation of a complete infrastructure that now provides tools for analysis of the global lipidome in cultured and primary cells. Here we illustrate the advancement of a gas chromatography mass spectrometry (GC/MS) procedure for the analysis of essential fatty acids in RAW 264.7 cells. Our method allows for the specific identification and quantification of over 30 fatty acids present in cells in their free form in a single analytical GC/MS run. Free fatty acids are selectively extracted in the presence of deuterated internal standards, which permit subsequent estimation of extraction efficiencies and quantification with high accuracy. Mass spectrometer conditions were optimized for single-ion monitoring, which provides an extremely sensitive technology to measure fatty acids from biological samples in trace amounts. These methods will be presented in the context of our broader effort to analyze all fatty acids as well as their metabolites in inflammatory cells

An integrated model of eicosanoid metabolism and signaling based on lipidomics flux analysis.

There is increasing evidence for a major and critical involvement of lipids in signal transduction and cellular trafficking, and this has motivated large-scale studies on lipid pathways. The Lipid Metabolites and Pathways Strategy consortium is actively investigating lipid metabolism in mammalian cells and has made available time-course data on various lipids in response to treatment with KDO(2)-lipid A (a lipopolysaccharide analog) of macrophage RAW 264.7 cells. The lipids known as eicosanoids play an important role in inflammation. We have reconstructed an integrated network of eicosanoid metabolism and signaling based on the KEGG pathway database and the literature and have developed a kinetic model. A matrix-based approach was used to estimate the rate constants from experimental data and these were further refined using generalized constrained nonlinear optimization. The resulting model fits the experimental data well for all species, and simulated enzyme activities were similar to their literature values. The quantitative model for eicosanoid metabolism that we have developed can be used to design experimental studies utilizing genetic and pharmacological perturbations to probe fluxes in lipid pathways

Synthesis of 2-oxoamides based on sulfonamide analogs of gamma-amino acids and their activity on phospholipase A2.

A variety of lipophilic 2-oxoamides containing sulfonamide analogs of gamma-amino acids as well as acyl sulfonamides of gamma-aminobutyric acid were synthesized. Their ability to inhibit intracellular GIVA cPLA2 and GVIA iPLA2 as well as secreted GV sPLA2 was evaluated. The sulfonamide group seems a bioisosteric group suitable to replace the carboxyl group in 2-oxoamide inhibitors of GVIA cPLA2

Substrate Specificity of the Escherichia coli Outer Membrane Protease OmpT

OmpT is a surface protease of gram-negative bacteria that has been shown to cleave antimicrobial peptides, activate human plasminogen, and degrade some recombinant heterologous proteins. We have analyzed the substrate specificity of OmpT by two complementary substrate filamentous phage display methods: (i) in situ cleavage of phage that display protease-susceptible peptides by Escherichia coli expressing OmpT and (ii) in vitro cleavage of phage-displayed peptides using purified enzyme. Consistent with previous reports, OmpT was found to exhibit a virtual requirement for Arg in the P1 position and a slightly less stringent preference for this residue in the P1′ position (P1 and P1′ are the residues immediately prior to and following the scissile bond). Lys, Gly, and Val were also found in the P1′ position. The most common residues in the P2′ position were Val or Ala, and the P3 and P4 positions exhibited a preference for Trp or Arg. Synthetic peptides based upon sequences selected by bacteriophage display were cleaved very efficiently, with k(cat)/K(m) values up to 7.3 × 10(6) M(−1) s(−1). In contrast, a peptide corresponding to the cleavage site of human plasminogen was hydrolyzed with a k(cat)/K(m) almost 10(6)-fold lower. Overall, the results presented in this work indicate that in addition to the P1 and P1′ positions, additional amino acids within a six-residue window (between P4 and P2′) contribute to the binding of substrate polypeptides to the OmpT binding site