Vagus Nerve Stimulation in Refractory Epilepsy: Effects on Pro- and Anti-Inflammatory Cytokines in Peripheral Blood

Objective: The vagus nerve has important immunological functions that may be relevant for its anticonvulsive action. We postulate that this anticonvulsive action is activated by a shift in the immune system resulting in a reduction of neurotoxic and an increase of neuroprotective tryptophan metabolites. Methods: Eleven patients with refractory epilepsy and 11 controls matched for age and gender were included in this study. The primary outcome measure was a 50% seizure reduction. Other variables were pro-inflammatory cytokines IL-6 and TNF-alpha, anti-inflammatory cytokine IL-10, cortisol, and the tryptophan metabolites 3-hydroxykynurenine (3-OH-KYN), kynurenic acid (KYNA), kynurenine, serotonin (5-HT) and 5-hydroxyindol acetic acid (5-HIAA). Blood samples were scheduled during baseline, and in week 28 of add-on treatment. Results: IL-6 levels were higher in the responders than in the control group, and decreased after vagus nerve stimulation (VNS), whereas IL-10 was low and increased after VNS. In nonresponders, VNS resulted in an increase of IL-6 plasma levels and in a decrease of IL-10. Cortisol concentrations are higher in the epilepsy group than in the control group. After VNS, these concentrations decreased. The concentrations of the tryptophan metabolites were lower in the epilepsy group than in the control group. The KYNA ratios are defined as the ratio of neuroprotective KYNA versus neurotoxic 3-OH-KYN and KYNA versus neurotoxic kynurenine: these ratios were lower in epilepsy patients than in controls, and they both moderately increased after VNS. Conclusion: The outcome of this preliminary study indicates that VNS causes a rebalancing of the immune system. This results in: (1) a reduction of neurotoxic and an increase of neuroprotective kynurenine metabolites and (2) in the normalization of cortisol levels. Copyright (C) 2010 S. Karger AG, Base

Maximizing Use of an Extension Beef Cattle Data Set: Part 2—Reproductive Rates

Previously, we described CHAPS20Y, a historical data set, and trends in CHAPS20Y calving distributions. In this article, we describe reproductive rates, including total females exposed to bull(s), pregnancy, pregnancy loss, calving, calf death loss, weaning, culling, and replacement percentages. Yearly mean exposed females increased from 1994 through 2013, consistent with a greater replacement percentage versus culling percentage. Yearly mean reproductive percentages varied over time. Factors such as weather, body condition, temperament, nutrition, and health likely contributed to this variation. CHAPS20Y is a tool Extension professionals can use to understand beef reproductive rates and help producers set and achieve their herd management goals

Maximizing Use of Extension Beef Cattle Benchmarks Data Derived from Cow Herd Appraisal Performance Software

One goal of Extension is to provide practical information that makes a difference to producers. Cow Herd Appraisal Performance Software (CHAPS) has provided beef producers with production benchmarks for 30 years, creating a large historical data set. Many such large data sets contain useful information but are underutilized. Our goal was to create a 20-year data set (CHAPS20Y) to examine trends in beef production from 1994 to 2013. In this article, we describe the CHAPS program and the process used to select herds for CHAPS20Y. We hope to publish additional related articles that will examine trends in calving distributions, reproduction, and growth and discuss implications for producers and Extension

Doppler Ultrasonographic Assessment of Abdominal Aortic Flow to Evaluate the Hemodynamic Relevance of Left-to-Right Shunting Patent Ductus Arteriosus in Dogs

In this multicenter, prospective, observational study, abdominal aortic flow was examined with pulsed-wave Doppler ultrasound in dogs with a left-to-right shunting patent ductus arteriosus (PDA) and in apparently healthy dogs. Forty-eight dogs with a PDA and 35 controls were included. In the dogs with a PDA, 37/48 had hemodynamically significant PDAs (hsPDAs) while 11/48 had non-hsPDAs, based on the presence or absence of echocardiographic signs of left-sided volume overload, respectively. In 12 dogs (4/35 control dogs, 7/37 dogs with an hsPDA and 1/11 dogs with a non-hsPDA), the diastole was too short to visualize the end-diastolic flow. Antegrade end-diastolic flow was observed in 30/35 controls and 6/11 dogs with a non-hsPDA. Absent end-diastolic flow was observed in 1/35 control dogs and 3/11 dogs with a non-hsPDA. Retrograde end-diastolic flow was observed in 30/37 dogs with an hsPDA and 1/11 dogs with a non-hsPDA. Twenty-one dogs (15 with an hsPDA and 6 with a non-hsPDA) were reassessed after PDA closure, and, in 19/21, end-diastolic flow was visualized: 17/19 showed an antegrade flow, 1/19 an absent flow and 1/19 a retrograde flow. Sensitivity and specificity of retrograde end-diastolic flow for detection of hsPDAs were 100% and 90%, respectively. In conclusion, ultrasonographic assessment of abdominal aortic flow was feasible in dogs with PDA. However, end-diastolic flow was not always visualized. The presence of a retrograde end-diastolic flow was an accurate finding for discriminating hsPDAs and non-hsPDAs

Identification of a major locus interacting with MC1R and modifying black coat color in an F2 Nellore-Angus population

BACKGROUND: In cattle, base color is assumed to depend on the enzymatic activity specified by the MC1R locus, i.e. the extension locus, with alleles coding for black (E( D )), red (e), and wild-type (E( + )). In most mammals, these alleles are presumed to follow the dominance model of E( D ) > E( + ) > e, although exceptions are found. In Bos indicus x Bos taurus F(2) cattle, some E( D )E( + ) heterozygotes are discordant with the dominance series for MC1R and display various degrees of red pigmentation on an otherwise predicted black background. The objective of this study was to identify loci that modify black coat color in these individuals. RESULTS: Reddening was classified with a subjective scoring system. Interval analyses identified chromosome-wide suggestive (P < 0.05) and significant (P < 0.01) QTL on bovine chromosomes (BTA) 4 and 5, although these were not confirmed using single-marker association or Bayesian methods. Evidence of a major locus (F = 114.61) that affects reddening was detected between 60 and 73 Mb on BTA 6 (Btau4.0 build), and at 72 Mb by single-marker association and Bayesian methods. The posterior mean of the genetic variance for this region accounted for 43.75% of the genetic variation in reddening. This region coincided with a cluster of tyrosine kinase receptor genes (PDGFRA, KIT and KDR). Fitting SNP haplotypes for a 1 Mb interval that contained all three genes and centered on KIT accounted for the majority of the variation attributed to this major locus, which suggests that one of these genes or associated regulatory elements, is responsible for the majority of variation in degree of reddening. CONCLUSIONS: Recombinants in a 5 Mb region surrounding the cluster of tyrosine kinase receptor genes implicated PDGFRA as the strongest positional candidate gene. A higher density marker panel and functional analyses will be required to validate the role of PDGFRA or other regulatory variants and their interaction with MC1R for the modification of black coat color in Bos indicus influenced cattle

Wind vane correction during yaw misalignment for horizontal-axis wind turbines

This paper investigates the accuracy of wind direction measurements for horizontal-axis wind turbines and their impact on yaw control. The yaw controller is crucial for aligning the rotor with the wind direction and optimizing energy extraction. Wind direction is conventionally measured by one or two wind vanes located on the nacelle, but the proximity of the rotor can interfere with these measurements. The authors show that the conventional corrections, including low-pass filters and calibrated offset correction, are inadequate to correct a systematic overestimation of the wind direction deviation caused by the rotor misalignment. This measurement error can lead to an overcorrection of the yaw controller and, thus, to an oscillating yaw behaviour, even if the wind direction is relatively steady. The authors present a theoretical basis and methods for quantifying the wind vane measurement error and validate their findings using computational fluid dynamics simulations and operational data from two commercial wind turbines. Additionally, the authors propose a correction function that improves the wind vane measurements and demonstrate its effectiveness in two free-field experiments. Overall, the paper provides new insights into the accuracy of wind direction measurements and proposes solutions to improve the yaw control for horizontal-axis wind turbines.</p