Foot-and-mouth disease in red deer - experimental infection and test methods performance

Summary: The aim of this study was to evaluate a number of foot-and-mouth disease (FMD) test methods for use in red deer. Ten animals were intranasally inoculated with the FMD virus (FMDV) O UKG 11/2001, monitored for clinical signs, and samples taken regularly (blood, serum, oral swabs, nasal swabs, probang samples and lesion swabs, if present) over a 4-week period. Only one animal, deer 1103, developed clinical signs (lesions under the tongue and at the coronary band of the right hind hoof). It tested positive by 3D and IRES real-time reverse transcription polymerase chain reaction (rRT-PCR) in various swabs, lesion materials and serum. In a non-structural protein (NSP) in-house ELISA (NSP-ELISA-IH), one commercial ELISA (NSP-ELISA-PR) and a commercial antibody NSP pen side test, only deer 1103 showed positive results from day post-inoculation (dpi) 14 onwards. Two other NSP-ELISAs detected anti-NSP serum antibodies with lower sensitivity. It also showed rising antibody levels in the virus neutralization test (VNT), the in-house SPO-ELISA-IH and the commercial SPO-ELISA-PR at dpi 9, and in another two commercial SPO-ELISAs at dpi 12 (SPO-ELISA-IV) and dpi 19 (SPO-ELISA-IZ), respectively. Six of the red deer that had been rRT-PCR and antibody negative were re-inoculated intramuscularly with the same O-serotype FMDV at dpi 14. None of these animals became rRT-PCR or NSP-ELISA positive, but all six animals became positive in the VNT, the in-house SPO-ELISA-IH and the commercial SPO-ELISA-PR. Two other commercial SPO-ELISAs were less sensitive or failed to detect animals as positive. The rRT-PCRs and the four most sensitive commercial ELISAs that had been used for the experimentally inoculated deer were further evaluated for diagnostic specificity (DSP) using 950 serum samples and 200 nasal swabs from non-infected animals. DSPs were 100% for the rRT-PCRs and between 99.8 and 100% for the ELISAs.

Application of the Ceditest® FMDV type O and FMDV-NS enzyme-linked immunosorbent assays for detection of antibodies against foot-and-mouth disease virus in selected livestock and wildlife species in Uganda

Diagnosis and control of Foot-and-mouth disease virus (FMDV) requires rapid and sensitive diagnostic tests. Two antibody enzyme-linked immunosorbent assay (ELISA) kits, Ceditest® FMDV-NS for the detection of antibodies against the nonstructural proteins of all FMDV serotypes and Ceditest® FMDV type O for the detection of antibodies against serotype O, were evaluated under African endemic conditions where the presence of multiple serotypes and the use of nonpurified vaccines complicate serological diagnosis. Serum samples from 218 African buffalo, 758 cattle, 304 goats, and 88 sheep were tested using both kits, and selected samples were tested not only in serotype-specific ELISAs for antibodies against primarily FMDV serotype O, but also against other serotypes. The FMDV-NS assay detected far more positive samples (93%) than the FMDV type O assay (30%) in buffalo (P < 0.05), with predominant antibodies against the South African Territories (SAT) serotypes, while the seroprevalence was generally comparable in cattle with antibodies against serotype O elicited by infection and/or vaccination. However, some districts had higher seroprevalence using the FMDV type O assay indicating vaccination without infection, while 1 cattle herd with antibodies against the SAT serotypes had far more positive samples (85%) using the FMDV-NS versus the FMDV type O (10%), consistent with the latter test's lower sensitivity for antibodies against SAT serotypes. Based on the current investigation, the FMDV type O ELISA may be limited by the presence of SAT serotypes. The FMD NS assay worked well as a screening test for antibodies against all FMDV serotypes present in Uganda; however, as long as nonpurified vaccines are applied in the region, this test cannot be used to differentiate between vaccinated and infected animals.

Pan-serotype diagnostic for foot-and-mouth disease using the consensus antigen of nonstructural protein 3B

An amino acid consensus sequence for the seven serotypes of foot-and-mouth disease virus (FMDV) nonstructural protein 3B, including all three contiguous repeats, and its use in the development of a pan-serotype diagnostic test for all seven FMDV serotypes are described. The amino acid consensus sequence of the 3B protein was determined from a multiple-sequence alignment of 125 sequences of 3B. The consensus 3B (c3B) protein was expressed as a soluble recombinant fusion protein with maltose-binding protein (MBP) using a bacterial expression system and was affinity purified using amylose resin. The MBP-c3B protein was used as the antigen in the development of a competition enzyme-linked immunosorbent assay (cELISA) for detection of anti-3B antibodies in bovine sera. The comparative diagnostic sensitivity and specificity at 47% inhibition were estimated to be 87.22% and 93.15%, respectively. Reactivity of c3B with bovine sera representing the seven FMDV serotypes demonstrated the pan-serotype diagnostic capability of this bioreagent. The consensus antigen and competition ELISA are described here as candidates for a pan-serotype diagnostic test for FMDV infection.

Effects of approach velocity and foot-target characteristics on the visual regulation of step length

Two questions emerge from the literature concerning the perceptual-motor processes underlying the visual regulation of step length. The first concerns the effects of velocity on the onset of visual control (VCO), when visual regulation of step length begins during goal-directed locomotion. The second concerns the effects of different obstacles such as a target or raised surface on step length regulation. In two separate experiments, participants (Experiment 1 & 2: n=12, 6 female, 6 male) walked, jogged, or sprinted towards an obstacle along a 10 m walkway, consisting of two marker-strips with alternating black and white 0.50 m markings. Each experiment consisted of three targeting or obstacle tasks with the requirement to both negotiate and continue moving (run-through) through the target. Five trials were conducted for each task and approach speed, with trials block randomised between the six participants of each gender. One 50 Hz video camera panned and filmed each trial from an elevated position, adjacent to the walkway. Video footage was digitized to deduce the gait characteristics. Results for the targeting tasks indicate a linear relationship between approach velocity and accuracy of final foot placement (r=0.89). When foot placement was highly constrained by the obstacle step length shortened during the entire approach. VCO was found to occur at an earlier tau-margin for lower approach velocities for both experiments, indicating that the optical variable ‘tau' is affected by approach velocity. A three-phase kinematic profile was found for all tasks, except for the take-off board condition when sprinting. Further research is needed to determine whether this velocity affect on VCO is due to ‘whole-body' approach velocity or whether it is a function of the differences between gait modes.

Elevation in tanis expression alters glucose metabolism and insulin sensitivity in H4IIE cells

Increased hepatic glucose output and decreased glucose utilization are implicated in the development of type 2 diabetes. We previously reported that the expression of a novel gene, Tanis, was upregulated in the liver during fasting in the obese/diabetic animal model Psammomys obesus. Here, we have further studied the protein and its function. Cell fractionation indicated that Tanis was localized in the plasma membrane and microsomes but not in the nucleus, mitochondria, or soluble protein fraction. Consistent with previous gene expression data, hepatic Tanis protein levels increased more significantly in diabetic P. obesus than in nondiabetic controls after fasting. We used a recombinant adenovirus to increase Tanis expression in hepatoma H4IIE cells and investigated its role in metabolism. Tanis overexpression reduced glucose uptake, basal and insulin-stimulated glycogen synthesis, and glycogen content and attenuated the suppression of PEPCK gene expression by insulin, but it did not affect insulin-stimulated insulin receptor phosphorylation or triglyceride synthesis. These results suggest that Tanis may be involved in the regulation of glucose metabolism, and increased expression of Tanis could contribute to insulin resistance in the liver.

Effect of creatine ingestion on glucose tolerance and insulin sensitivity in men

Purpose: This study investigated whether acute (5 d) and/or short-term (28 d) creatine (Cr) ingestion altered glucose tolerance or insulin action in healthy, untrained men (aged 26.9 ± 5.7 yr; SD). Methods : Subjects were randomly allocated to either a Cr (N = 8) or placebo group (N = 9) and were tested in the control condition (presupplementation), and after 5 and a further 28 d of supplementation. The Cr group ingested 20 g and 3 g·d-1 of Cr for the first 5 and following 28 d, respectively. The placebo group ingested similar amounts of glucose over the same time period. During each testing period, subjects underwent an oral glucose tolerance test (OGTT) to determine insulin sensitivity, and six subjects from each group underwent a muscle biopsy before each OGTT. Results : Cr supplementation resulted in an increased (P < 0.05) muscle TCr content after both the acute and short-term loading phase compared with placebo. Neither acute nor short-term Cr supplementation influenced skeletal muscle glycogen content, glucose tolerance, or measures of insulin sensitivity. Conclusions: These findings demonstrated that acute Cr supplementation (20 g·d-1 for 5 d) followed by short-term Cr supplementation (3 g·d-1 for 28 d) did not alter insulin action in healthy, active untrained men.

Foot-targeting in reaching and grasping

Foot positioning was investigated when right-handed (Experiment One) and left handed adults (Experiment Two) stopped walking to grasp a stationary 70 mm ball at shoulder height. In both experiments centroid location formed by the toe and heel coordinates relative to the object was highly consistent within a target-location condition, demonstrating a foot-targeting phenomenon. Centroid location in the anterior-posterior direction was uninfluenced by grasping hand but the centroid shifted right for left hand grasps and left for right hand grasps. With the target either centrally located or on the same side as the dominant hand, foot positioning brought the grasping hand closer to the target in the medial-lateral direction. When the target object was aligned with the shoulder opposite the dominant hand both groups adopted foot positions to the left of the target. Thus, neither group adopted optimal foot position when the target was located opposite their dominant hand. Foot orientation angle relative to the target was also influenced by choice of grasping hand. Collectively, the findings demonstrate a close association between grasping hand and foot position when approaching to reach and grasp an object but also suggest that foot-dominance may influence medial-lateral centroid location.

Spatio-temporal selectivity of loss of colour and luminance contrast sensitivity with mutiple sclerosis and optic neuritis

Colour and luminance-contrast thresholds were measured in the presence of dynamic Random Luminance-contrast Masking (RLM) in individuals who had had past diagnoses of optic neuritis (ON) some of whom have progressed to a diagnosis of multiple sclerosis (MS). To explore the spatio-temporal selectivity of chromatic and luminance losses in MS/ON, thresholds were measured using three different sizes and modulation rates of the RLM displays: small checks modulating slowly, medium-sized checks with moderate modulation and large checks modulating rapidly. The colour of the chromatic stimuli used were specified in a cone-excitation space to measure relative impairments in red–green and blue–yellow chromatic channels. These observers showed chromatic thresholds along the L/(L + M) axis that were higher than those along the S-cone axis for all display sizes/modulation rates and both red-green and blue-yellow colour thresholds were higher than luminance-contrast thresholds. The principal change in thresholds with spatio-temporal changes in the display was a reduction in thresholds for L/(L + M) and S-cones with increasing check size and modulation rate. However, luminance contrast thresholds did not change with display size/rate. These results are consistent with MS/ON selectively affecting processing in colour pathways rather than in the magnocellular pathway, and that within the colour pathways neurones with opposed L- and M-cone inputs are more damaged than colour-opponent neurons with input from S-cones.

Reinforcement sensitivity theory (RST) and body change behaviour in males

According to the unrevised Reinforcement Sensitivity Theory two motivational systems shape personality: a behavioural approach system (BAS) that determines sensitivity to rewards, and a behavioural inhibition system (BIS) that determines sensitivity to punishments. The role of reinforcement sensitivity in body change behaviour in males was explored with a non-clinical sample of 120 men aged 18–40 years. Self-reported symptoms of unhealthy weight loss (weight preoccupation, fasting, bingeing/purging) and body development (muscle/size preoccupation, obligatory exercise, use of chemical supplements) were regressed on measures of BAS and BIS sensitivity. Significant relationships were observed between BAS sensitivity and body development, and between BIS sensitivity and weight loss. These relationships were mediated by internalization of the athletic/muscular ideal, body comparisons, the importance of achieving one’s ideal or ‘best possible’ body (in the case of BAS but not BIS), and body dissatisfaction (in the case of BIS but not BAS). These results support the proposition that body development in males is influenced by sensitivity to rewards associated with achieving a certain body shape, and that weight loss is influenced by sensitivity to punishments associated with possessing an unsatisfactory body shape.

The influence of sensitivity to reward on reactivity to alcohol-related cues

Aims. To investigate the role of sensitivity to reward in mediating social drinkers' reactivity to alcohol cues. Design. A standard cue-reactivity paradigm was employed. Two groups of social drinkers (heavy and ight) were assessed after exposure to the sight, smell and taste of a neutral cue (water) and then an alcohol cue (glass of beer). Setting. Sessions were conducted in a laboratory based environment. Participants. Twenty heavy (12 males, eight females) and 18 light social drinkers (seven males, 11 females) were recruited; mean age was 23.6 years. Measurements. The Card Arranging Reward Responsivity Objective Test (CARROT), assessing behavioural responsiveness to a monetary incentive; urge to drink; positive affect; and the BAS scales, assessing sensitivity to reward. Findings. Heavy drinkers displayed a significant increase in responsivity to rewards (i.e. CARROT) and self-reported urge to drink, bur not positive affect, after exposure to alcohol. For the heavy drinkers, heightened sensitivity to reward (i.e. BAS scales) was significantly related to cue-elicited urge to drink and positive affect. Conclusion. The results are consistent with a conditioned appetitive motivational model of alcohol use and suggest that Gray's theory of personality may be of some benefit in explaining variation in reactivity responses.

Effect of relaxation on pressure sensitivity index in a Zr-based metallic glass

Shear-banding features of as-cast and annealed Zr_41.2Ti_13.8Cu_12.5Ni₁₀Be_22.5 bulk metallic glass were investigated through Rockwell indentation tests. Isothermal annealing of the as-cast samples was conducted at temperatures below its glass transition temperature, Tg. The exothermal enthalpy during continuous heating below Tg decreases with increasing annealing temperature, indicating the gradual reduction of free-volume upon annealing. The observation on the morphology of shear-banding pattern around the indents implies a reduced shear bands activity in the annealed samples. The included angles (2θ) between two families of shear bands emanating from the edge of Rockwell indent decrease from 88° for the as-cast sample to 79° for the sample annealed at 633 K for 1 h, indicating a pressure sensitive plasticity. By Mohr–Coulomb criterion, the pressure sensitive index can be obtained on the basis of the measured 2θ, which increases with increasing annealing temperature, indicating an increase of “atomistic friction” due to the reduction of the free volume upon annealing.

Upregulation of peroxisome proliferator-activated receptor gamma coactivator gene (PGC1A) during weight loss is related to insulin sensitivity but not to energy expenditure

Aims/hypothesis We investigated whether skeletal muscle peroxisome proliferator-activated receptor gamma coactivator-1 (PGC1A; also known as PPARGC1A) and its target mitofusin-2 (MFN2), as well as carnitine palmitoyltransferase-1 (CPT1; also known as carnitine palmitoyltransferase 1A [liver] [CPT1A]) and uncoupling protein (UCP)3, are involved in the improvement of insulin resistance and/or in the modification of energy expenditure during surgically induced massive weight loss.
Materials and methods Seventeen morbidly obese women (mean BMI: 45.9 ± 4 kg/m2) were investigated before, and 3 and 12 months after, Roux-en-Y gastric bypass (RYGB). We evaluated insulin sensitivity by the euglycaemic–hyperinsulinaemic clamp, energy expenditure and substrate oxidation by indirect calorimetry, and muscle mRNA expression by PCR.
Results Post-operatively, PGC1A was enhanced at 3 (p = 0.02) and 12 months (p = 0.03) as was MFN2 (p = 0.008 and p = 0.03 at 3 and 12 months respectively), whereas UCP3 was reduced (p = 0.03) at 12 months. CPT1 did not change. The expression of PGC1A and MFN2 were strongly (p < 0.0001) related. Insulin sensitivity, which increased after surgery (p = 0.002 at 3, p = 0.003 at 12 months), was significantly related to PGC1A and MFN2, but only MFN2 showed an independent influence in a multiple regression analysis. Energy expenditure was reduced at 3 months post-operatively (p = 0.001 vs before RYGB), remaining unchanged thereafter until 12 months. CPT1 and UCP3 were not significantly related to the modifications of energy expenditure or of lipid oxidation rate.
Conclusions/interpretation Weight loss upregulates PGC1A, which in turn stimulates MFN2 expression. MFN2 expression significantly and independently contributes to the improvement of insulin sensitivity. UCP3 and CPT1 do not seem to influence energy expenditure after RYGB.

Indentation study on the pressure sensitivity of a ZR-based bulk metallic glass

Spherical indentation test was conducted on as-cast and annealed Zr_41.2Ti_13.8Cu_12.5Ni₁₀Be_22.5 bulk metallic glass, and the evolution of the morphology of the deformation zone of indents upon annealing was investigated. The DSC traces of the as-cast and annealed samples show that the enthalpy change at the glass transition, ΔH, decreases with the increasing of annealing temperature, indicating the reduction of the free volume upon annealing. The morphology of the indents implies a reduced shear band activity in the annealed samples. The included angles (2θ) between two families of shear bands emanating from the edge of spherical indent in the as-cast and the annealed samples were measured to be in the range of 88-79°, which decrease with the increasing of annealing temperature, indicating pressure sensitive plasticity in the as-cast and annealed samples. By Mohr–Coulomb criterion, the pressure sensitive index, α, can be obtained on the basis of the measured 2θ. The sensitivity index increases with increasing temperature, implying an increase of 'atomistic friction' due to the reduction of the free volume upon annealing.