AN ECONOMIC ANALYSIS OF GENETIC INFORMATION: LEPTIN GENOTYPING IN FED CATTLE

The use of genetic knowledge is widespread in crop production but is just recently being utilized in livestock production. This study investigates the economic value to feedlots of a polymorphism in the bovine leptin gene. Previous studies indicate that this polymorphism is associated with fat deposition. Since fed cattle are often priced on a grid that considers both yield and quality grades, fat deposition is an important factor in the value and profitability of fed cattle. Using data from 590 crossbred steers and heifers, we estimate growth curves for relevant biological traits, both with and without genotypic information. Using the resulting functions, we then simulate carcass traits to various days-on-feed and compute the associated profit under three price grids. Maximum profits are determined in an unconstrained profit maximization model and in a model that constrains cattle to be marketed in 45-head "potloads." Results indicate that leptin genotypic knowledge has little impact on optimal days-on-feed but may play a role in valuing feeder cattle. The differences in value of cattle varied by as much as $37 per head between genotypes.genetics, leptin genotype, beef cattle, value of information, Livestock Production/Industries,

Antibiotic drug use of children in the Netherlands from 1999 till 2005

Objective Antibiotics are the most commonly prescribed drugs used by children. Excessive and irrational use of antibiotic drugs is a world-wide concern. We performed a drug utilization study describing the patterns of antibiotic use in children aged 0-19 years between 1999 and 2005 in the Netherlands. Methods We used IADB.nl, a database with pharmacy drug dispensing data covering a population of 500,000 people and investigated all prescriptions of oral antibiotic drugs (ATC J01) for children Results The total number of antibiotic prescriptions per 1000 children per year ranged from 282 in 2004 to 307 in 2001 and did not change between years during the study period in a clinically relevant way. The prevalence of receiving at least one prescription varied between 17.8% in 2004 and 19.3% in 2001. Amoxicillin was the most frequently prescribed drug (46.4% of all antibiotic prescriptions in 1999 and 43.2% in 2005). Between 1999 and 2005 there was a shift from the small-spectrum phenethicillin, a penicillin preparation [ratio 2005/1999 0.76; 95% confidence interval (CI) 0.72-0.81], to amoxicillin/clavulanic acid (ratio 2005/1999 1.70; 95% CI 1.61-1.79) and from the old macrolide erythromycin (ratio 2005/1999 0.35; 95% CI 0.32-0.39) to the new macrolide antibiotic azithromycin (ratio 2005/1999 1.78; 95% CI 1.65-1.92). Conclusion The use of antibiotic drugs in treating children in the Netherlands is comparable to that in other northern European countries. Broad-spectrum antibiotics were prescribed more frequently than recommended by the guidelines and increased during our study period. Initiatives to improve guideline-directed antibiotic prescribing are strongly recommended

Effect of vitamin K2 on postural sway in older people who fall:a randomized controlled trial

OBJECTIVES: Vitamin K is thought to be involved in both bone health and maintenance of neuromuscular function. We tested the effect of vitamin K2 supplementation on postural sway, falls, healthcare costs, and indices of physical function in older people at risk of falls.DESIGN: Parallel-group double-blind randomized placebo-controlled trial.SETTING: Fourteen primary care practices in Scotland, UK.PARTICIPANTS: A total of 95 community-dwelling participants aged 65 and older with at least two falls, or one injurious fall, in the previous year.INTERVENTION: Once/day placebo, 200 μg or 400 μg of oral vitamin K2 for 1 year.MEASUREMENTS: The primary outcome was anteroposterior sway measured using sway plates at 12 months, adjusted for baseline. Secondary outcomes included the Short Physical Performance Battery, Berg Balance Scale, Timed Up &amp; Go Test, quality of life, health and social care costs, falls, and adverse events.RESULTS: Mean participant age was 75 (standard deviation [SD] = 7) years. Overall, 58 of 95 (61%) were female; 77 of 95 (81%) attended the 12-month visit. No significant effect of either vitamin K2 dose was seen on the primary outcome of anteroposterior sway (200 μg vs placebo: -.19 cm [95% confidence interval [CI] -.68 to .30; P = .44]; 400 μg vs placebo: .17 cm [95% CI -.33 to .66; P = .50]; or 400 μg vs 200 μg: .36 cm [95% CI -.11 to .83; P = .14]). Adjusted falls rates were similar in each group. No significant treatment effects were seen for other measures of sway or secondary outcomes. Costs were higher in both vitamin K2 arms than in the placebo arm.CONCLUSION: Oral vitamin K2 supplementation did not improve postural sway or physical function in older people at risk of falls.</p

A Cost-Effective Design for a Neutrino Factory

There have been active efforts in the U.S., Europe, and Japan on the design of a Neutrino Factory. This type of facility produces intense beams of neutrinos from the decay of muons in a high energy storage ring. In the U.S., a second detailed Feasibility Study (FS2) for a Neutrino Factory was completed in 2001. Since that report was published, new ideas in bunching, cooling and acceleration of muon beams have been developed. We have incorporated these ideas into a new facility design, which we designate as Study 2B (ST2B), that should lead to significant cost savings over the FS2 design.Comment: 46 pages, 38 figures; to be submitted to Physical Review Special Topics: Accelerators and Beam

Ground-state properties of tubelike flexible polymers

In this work we investigate structural properties of native states of a simple model for short flexible homopolymers, where the steric influence of monomeric side chains is effectively introduced by a thickness constraint. This geometric constraint is implemented through the concept of the global radius of curvature and affects the conformational topology of ground-state structures. A systematic analysis allows for a thickness-dependent classification of the dominant ground-state topologies. It turns out that helical structures, strands, rings, and coils are natural, intrinsic geometries of such tubelike objects

Conformational Mechanics of Polymer Adsorption Transitions at Attractive Substrates

Conformational phases of a semiflexible off-lattice homopolymer model near an attractive substrate are investigated by means of multicanonical computer simulations. In our polymer-substrate model, nonbonded pairs of monomers as well as monomers and the substrate interact via attractive van der Waals forces. To characterize conformational phases of this hybrid system, we analyze thermal fluctuations of energetic and structural quantities, as well as adequate docking parameters. Introducing a solvent parameter related to the strength of the surface attraction, we construct and discuss the solubility-temperature phase diagram. Apart from the main phases of adsorbed and desorbed conformations, we identify several other phase transitions such as the freezing transition between energy-dominated crystalline low-temperature structures and globular entropy-dominated conformations.Comment: 13 pages, 15 figure

Screen-and-Treat Strategies for Albuminuria to Prevent Cardiovascular and Renal Disease:Cost-Effectiveness of Nationwide and Targeted Interventions Based on Analysis of Cohort Data From the Netherlands

Background: Albuminuria is a marker for renal and cardiovascular (CV) risk, allowing early diagnosis of subjects with elevated renal and CV risk. Objective: This study aimed to estimate the cost-effectiveness and budget impact of various population-based screen-and-treat scenarios for elevated albuminuria levels (ie, microalbuminuria) in the Netherlands. Methods: A multistate transition Markov model was developed to simulate the natural course of albuminuria-based disease progression to dialysis and occurrence of CV events. Several population-based strategies directed at screening for elevated albuminuria were evaluated. These strategies depended on urinary albumin concentration (UAC), urinary albumin excretion (UAE), and age. Transition probabilities were derived from the observational community-based Prevention of Renal and Vascular End Stage Disease (PREVEND) cohort study. Health care costs (in year-2008 euros) and life-years gained were calculated over an 8-year period. In the base-case analysis, we analyzed screening for and treatment of microalbuminuria. Screening for microalbuminuria involved prescreening for UAC >= 20 mg/L, followed by a confirmation test for UAE >= 30 mg/d. Other options based on combinations of albuminuria for UAC prescreening (no prescreening, and >= 10, >= 20, >= 100, and >= 200 mg/L) and UAE confirmation test (>= 15, >= 30, and 300 mg/d) for treatment were investigated in scenario analyses. Furthermore, these various strategies based on UAC and UAE values were analyzed in different subgroups based on age (all ages, aged >= 50 years, and aged >= 60 years). Results: The PREVEND study included 8592 Dutch residents aged 28 to 75 years at the time of initial screening. Among a hypothetical cohort of 1000 subjects identified and treated in the base-case analysis, it was estimated (based on PREVEND follow-up data) that, in the screening/treatment and no-screening scenarios, 76 versus 124 CV events occurred, 16 versus 27 CV deaths, and 3 versus 5 dialysis cases, respectively. The per-person difference in net costs for screening was calculated at (sic)926 ((sic)2003 vs (sic)1077), and prevention of CV deaths was estimated to gain 0.0421 discounted life-year per person. Correspondingly, the cost-effectiveness was estimated at (sic)22,000 per life-year gained. In the base-case analysis, probabilistic sensitivity analysis indicated that the likelihood of cost-effectiveness of a screen-and-treat strategy was 54%, 90%, and 95% for a maximum acceptable cost-effectiveness threshold of (sic)20,000, (sic)50,000, and (sic)80,000 per life-year gained, respectively. Higher albuminuria thresholds for screening and start of treatment further improved the cost-effectiveness but reduced the overall health gains achieved. Limiting screening to those subjects aged >= 50 and >= 60 years resulted in more favorable cost-effectiveness compared with population-based screening without age restriction. Conclusions: Our analyses suggest the potentially favorable cost-effectiveness of population-based screen

Are language production problems apparent in adults who no longer meet diagnostic criteria for attention-deficit/hyperactivity disorder?

In this study, we examined sentence production in a sample of adults (N = 21) who had had attention-deficit/hyperactivity disorder (ADHD) as children, but as adults no longer met DSM-IV diagnostic criteria (APA, 2000). This “remitted” group was assessed on a sentence production task. On each trial, participants saw two objects and a verb. Their task was to construct a sentence using the objects as arguments of the verb. Results showed more ungrammatical and disfluent utterances with one particular type of verb (i.e., participle). In a second set of analyses, we compared the remitted group to both control participants and a “persistent” group, who had ADHD as children and as adults. Results showed that remitters were more likely to produce ungrammatical utterances and to make repair disfluencies compared to controls, and they patterned more similarly to ADHD participants. Conclusions focus on language output in remitted ADHD, and the role of executive functions in language production