343 research outputs found
Progress Report: Centralized Ultrasound Processing
In January of 1998 Iowa State University began a twoyear cooperative research pilot project with the American Angus Association (AAA). The purpose was to organize the collection and interpretation of ultrasound images and calculate Expected Progeny Differences (EPDs) for genetic improvement of carcass traits using the ultrasound data. The first Centralized Ultrasound Processing (CUP) center was established and located at Iowa State Universtiy. In 1998 a select group of ultrasound technicians was trained following a unique protocol for the collection of ultrasound images including rump fat thickness, rib fat thickness, ribeye area and % intramuscular fat (marbling). Images for over 9,000 head of bulls, steers, replacement heifers and feedlot heifers were received and processed through the CUP laboratory during 1998. Many of the results of these data can be found in ASL R1625
Comparison of Sire Carcass EPD Rankings Using Real-time Ultrasound Measures from Yearling Angus Bulls Versus Using Measures from Developing Angus Heifers
The purpose of this study was to compare how sires rank on EPD generated solely from yearling Angus bull measures against those generated solely from developing heifer measures. Ultrasound EPD from heifer progeny ultrasound measures are ranking the sires identically to the EPD from the bull progeny ultrasound measures. The heifer data complement the bull data, and breeders should be encouraged to scan all of their developing females at or around 390 days of age to improve the accuracy of carcass EPD based ultrasound measures
Carcass EPDs from Angus Heifer Real-time Ultrasound Scans
The objective of this research was to use developing Angus heifer real-time ultrasound records to estimate genetic parameters and calculate carcass EPD for external 12-13th rib fat (FAT), rump fat thickness (RFAT), ribeye area (REA), and % intramuscular fat (%IMF). Heritability estimates are all of a moderate level (\u3e .40) and are higher than the estimates determined previously with bull-only ultrasound data. Genetic correlations are generally of the same magnitude and same sign as previously reported with the bull-only ultrasound data. Angus breeders need to be alerted to the fact that developing heifers can be scanned to accurately predict carcass merit in steer-mate half-sibs. The results of this research indicate that the heifer data may be more accurate than the half-sib yearling bulls findings because the heritability estimates from the heifer data are higher than those estimated from the yearling bull data
Genetic Relationship between Live Animal Ultrasound Measures and Scrotal Circumference in Yearling Angus Bulls
The purpose of this study was to determining the relationship between 365-d yearling scrotal circumference, scanning weight, and component ultrasound measured compositional traits. The genetic correlations between scrotal circumference measured at 365-d of age and other live animal measures are low. Of these five genetic relationships, the highest correlation is with % intramuscular fat (IMF) at .13. However, this is a low genetic correlation. The positive sign of the scrotal circumference-% IMF genetic correlation is encouraging for breeders wanting to increase scrotal circumference and % IMF at the same time. Scrotal circumference in yearling Angus bulls is not strongly linked genetically with weight and compositional traits. Selection programs for either increased retail product (as measured by weight and ribeye area) or quality (as measured by % IMF) will not result in an antagonistic effect on scrotal circumference
Powering Ocean Giants: The Energetics of Shark and Ray Megafauna
Shark and ray megafauna have crucial roles as top predators in many marine ecosystems, but are currently among the most threatened vertebrates and, based on historical extinctions, may be highly susceptible to future environmental perturbations. However, our understanding of their energetics lags behind that of other taxa. Such knowledge is required to answer important ecological questions and predict their responses to ocean warming, which may be limited by expanding ocean deoxygenation and declining prey availability. To develop bioenergetics models for shark and ray megafauna, incremental improvements in respirometry systems are useful but unlikely to accommodate the largest species. Advances in biologging tools and modelling could help answer the most pressing ecological questions about these iconic species
N-Acetylcysteine Reduces Cocaine-Cue Attentional Bias and Differentially Alters Cocaine Self-Administration Based on Dosing Order
Background—Disrupted glutamate homeostasis is thought to contribute to cocaine-use disorder, in particular, by enhancing the incentive salience of cocaine stimuli. n-Acetylcysteine might be useful in cocaine-use disorder by normalizing glutamate function. In prior studies, n-acetylcysteine blocked the reinstatement of cocaine seeking in laboratory animals and reduced the salience of cocaine stimuli and delayed relapse in humans.
Methods—The present study determined the ability of maintenance on n-acetylcysteine (0 or 2400 mg/day, counterbalanced) to reduce the incentive salience of cocaine stimuli, as measured by an attentional bias task, and attenuate intranasal cocaine self-administration (0, 30, and 60 mg). Fourteen individuals (N = 14) who met criteria for cocaine abuse or dependence completed this within-subjects, double-blind, crossover-design study.
Results—Cocaine-cue attentional bias was greatest following administration of 0 mg cocaine during placebo maintenance, and was attenuated by n-acetylcysteine. Cocaine maintained responding during placebo and n-acetylcysteine maintenance, but the reinforcing effects of cocaine were significantly attenuated across both maintenance conditions in participants maintained on n-acetylcysteine first compared to participants maintained on placebo first.
Conclusions—These results collectively suggest that a reduction in the incentive salience of cocaine-related stimuli during n-acetylcysteine maintenance may be accompanied by reductions in cocaine self-administration. These results are in agreement with, and link, prior preclinical and clinical trial results suggesting that n-acetylcysteine might be useful for preventing cocaine relapse by attenuating the incentive salience of cocaine cues
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The combined diabetes and renal control trial (C-DIRECT) - a feasibility randomised controlled trial to evaluate outcomes in multi-morbid patients with diabetes and on dialysis using a mixed methods approach
Background: This cluster randomised controlled trial set out to investigate the feasibility and acceptability of the “Combined Diabetes and Renal Control Trial” (C-DIRECT) intervention, a nurse-led intervention based on motivational interviewing and self-management in patients with coexisting end stage renal diseases and diabetes mellitus (DM ESRD). Its efficacy to improve glycaemic control, as well as psychosocial and self-care outcomes were also evaluated as secondary outcomes.
Methods: An assessor-blinded, clustered randomised-controlled trial was conducted with 44 haemodialysis patients with DM ESRD and ≥ 8% glycated haemoglobin (HbA1c), in dialysis centres across Singapore. Patients were randomised according to dialysis shifts. 20 patients were assigned to intervention and 24 were in usual care. The C-DIRECT intervention consisted of three weekly chair-side sessions delivered by diabetes specialist nurses. Data on recruitment, randomisation, and retention, and secondary outcomes such as clinical endpoints, emotional distress, adherence, and self-management skills measures were obtained at baseline and at 12 weeks follow-up. A qualitative evaluation using interviews was conducted at the end of the trial.
Results: Of the 44 recruited at baseline, 42 patients were evaluated at follow-up. One patient died, and one discontinued the study due to deteriorating health. Recruitment, retention, and acceptability rates of C-DIRECT were generally satisfactory HbA1c levels decreased in both groups, but C-DIRECT had more participants with HbA1c < 8% at follow up compared to usual care. Significant improvements in role limitations due to physical health were noted for C-DIRECT whereas levels remained stable in usual care. No statistically significant differences between groups were observed for other clinical markers and other patient-reported outcomes. There were no adverse effects.
Conclusions: The trial demonstrated satisfactory feasibility. A brief intervention delivered on bedside as part of routine dialysis care showed some benefits in glycaemic control and on QOL domain compared with usual care, although no effect was observed in other secondary outcomes. Further research is needed to design and assess interventions to promote diabetes self-management in socially vulnerable patients
Spectrum of Infection and Risk Factors for Human Monkeypox, United States, 2003
Infection is associated with proximity to virus-infected animals and their excretions and secretions
Incorporating New Technologies Into Toxicity Testing and Risk Assessment: Moving From 21st Century Vision to a Data-Driven Framework
Based on existing data and previous work, a series of studies is proposed as a basis toward a pragmatic early step in transforming toxicity testing. These studies were assembled into a data-driven framework that invokes successive tiers of testing with margin of exposure (MOE) as the primary metric. The first tier of the framework integrates data from high-throughput in vitro assays, in vitro-to-in vivo extrapolation (IVIVE) pharmacokinetic modeling, and exposure modeling. The in vitro assays are used to separate chemicals based on their relative selectivity in interacting with biological targets and identify the concentration at which these interactions occur. The IVIVE modeling converts in vitro concentrations into external dose for calculation of the point of departure (POD) and comparisons to human exposure estimates to yield a MOE. The second tier involves short-term in vivo studies, expanded pharmacokinetic evaluations, and refined human exposure estimates. The results from the second tier studies provide more accurate estimates of the POD and the MOE. The third tier contains the traditional animal studies currently used to assess chemical safety. In each tier, the POD for selective chemicals is based primarily on endpoints associated with a proposed mode of action, whereas the POD for nonselective chemicals is based on potential biological perturbation. Based on the MOE, a significant percentage of chemicals evaluated in the first 2 tiers could be eliminated from further testing. The framework provides a risk-based and animal-sparing approach to evaluate chemical safety, drawing broadly from previous experience but incorporating technological advances to increase efficiency
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