bluuebunny/crossref_metadata_2025 huggingface dataset:
The influence of different exercise regimens on the development of locomotion in the foal
Authors: BACK W. , SMIT L. D. , SCHAMHARDT H. C. , BARNEVELD A.
Published: June 2010

To study the influence of different exercise regimens on the development of locomotion, 40 Warmblood foals aged 1 week were subdivided into 3 groups: box‐rest, training and pasture exercise. The box‐rest group remained for 24 h a day in a box stall while the training group was housed similarly, but additionally received a 30 min workout with gallop sprints 6 times a week. The pasture group served as a control group and was kept at pasture for 24 h a day. After 5 months, the locomotion pattern at the trot of every foal was recorded overground with a 2‐D MacReflex gait analysis system. A randomly selected group of 19 foals was recorded again at age 11 months after they had been kept in an open loose box with access to a small paddock without any specific training for 6 months duration.

At 5 months of age the box‐rest group moved with a more protracted forelimb, and more extended shoulder and elbow joints than the pasture group. Carpal and fetlock joint kinematics were rather similar in all groups. In the hindlimb, the box‐rest foals were significantly different from the other 2 groups, reflected in a more retracted hindlimb, more hip extension, more flexed stifle and tarsal joints, and a larger maximal flexion of hip, stifle, tarsal and fetlock joints. In the simultaneous video recordings this locomotion pattern was visible as a hypermetric movement. The larger protraction in the forelimb and retraction in the hindlimb, as seen in the box‐rest group, is opposite to the interlimb coordination of a superior moving horse.

The pastured foals had a smaller range of motion of the shoulder and hip joint and less maximal step height of both fore and hind hooves, while the velocity and step length were similar between the 3 groups. Pastured foals could trot the same distance with less joint motion and therefore had a more efficient intralimb coordination. The training group moved in a way comparable with the box‐rest group in the forelimbs, and with the pastured foals in the hindlimbs. At age 11 months the differences in locomotion between the exercise groups had disappeared.

In conclusion, when is assumed that pasture exercise leads to a normally developed locomotion pattern, then at a similar velocity box‐rest foals trot with an abnormal, hypermetric and therefore inefficient and poorer locomotion pattern. When, superimposed on box‐rest, exercise is provided in the form of gallop sprints, this will mainly improve the hindlimb locomotion. These induced differences in locomotion pattern of foals can be reversed when the foals afterwards are subjected to the same exercise regimen again.
Colic surgery in 206 juvenile Thoroughbreds: survival and racing results
Authors: SANTSCHI E. M. , SLONE D. E. , EMBERTSON R. M. , CLAYTON M. K. , MARKEL M. D.
Published: June 2010

The purpose of our study was to determine the types of lesions that cause colic in juvenile Thoroughbreds, factors associated with these lesions and the subsequent survival and athletic performance of the juveniles. The age of juvenile Thoroughbreds requiring surgical exploration for abdominal pain has an influence on the type of lesion causing colic. The short‐term survival rate (discharge from the hospital) after colic surgery for foals was 85% and was strongly influenced by the lesion causing colic. Thirteen percent of juveniles recovered from the first surgery experienced another severe colic episode requiring additional surgery or euthanasia. Eight percent of foals recovered from the first celiotomy developed adhesions. Adhesion formation was related to the initial lesion causing colic and the foals' age at the first surgery. Foals being suckled (15 days to 6 months) were at greatest risk for adhesions and more frequently required multiple surgeries. Juvenile Thoroughbreds that had a celiotomy were significantly less able to race (63%) than their unaffected siblings (82%), and age at the initial surgery was associated with the percentage of horses that raced. However, affected foals able to race won as much money, raced as often, and made as many starts as their siblings. Colic and surgical treatment have a negative impact on athletic performance, but the majority of foals discharged from the hospital after colic surgery will perform athletically as adults.
Effect of extensive ileal resection with a large resulting mesenteric defect and stapled ileal stump in horses with a jejunocaecostomy: a comparison with other anastomotic techniques
Authors: BLADON B. M. , HILLYER M. H.
Published: June 2010

Extensive resection of the ileum of the horse, using automated stapling equipment followed by a stapled jejunocaecostomy, without closure of the mesenteric defect, was evaluated prospectively as a surgical treatment for lesions involving the distal small intestine. Of 153 horses treated surgically for colic, 10 horses with strangulating lesions involving the distal ileum were treated by extensive resection and jejunocaecal anastomosis leaving a residual mesenteric defect. These were compared with 12 horses with jejunoileal lesions treated by jejunocaecal anastomosis with closure of the mesentery, and 19 horses with distal jejunal lesions treated with an end‐to‐end jejunojejunal anastomosis and mesenteric closure. Long‐term (>7 months) and short‐term survival, duration of surgery, length of intestine resected, time from completion of surgery until the horse first defaecated and the highest recorded postoperative plasma fibrinogen level were assessed. There were no significant differences between the surgical techniques for any of the assessed parameters, but there was a trend to significance with a higher death rate following discharge from the hospital when cases of jejunocaecal anastomosis with a residual mesenteric defect were compared to cases of end‐to‐end jejunojejunal anastomosis with closure of the mesentery (P = 0.06). This study suggests that a stapled distal ileal resection and jejunocaecal anastomosis leaving a residual mesenteric defect is a satisfactory technique when pathological changes necessitate resection of the distal ileum. However, in this study, jejunocaecal anastomosis with or without mesenteric closure produced inferior results compared to jejunojejunal anastomosis.
Diagnosis and treatment of chronic recurrent caecal impaction
Authors: HUSKAMP B. , SCHEIDEMANN W.
Published: June 2010

Ninety‐six horses with chronic recurrent caecal impaction associated with hypertrophy of muscle layers in the caecal base or in the whole caecum were examined from 1990 to 1996. Enlargement of the caecocolic orifice was completed surgically in 58 horses. Of those horses having surgery, 50 were discharged from the hospital while 8 were subjected to euthanasia at the hospital due to complications. Twenty‐seven of the 50 horses discharged were normal at follow‐up while 23 died or were subjected to euthanasia due to acute or recurrent colic, recurrent impaction in the ascending or descending colon, complete caecal muscle layer hypertrophy, stomach rupture or lymphosarcoma. Approximately 50% of the cases were successfully treated by surgical enlargement of the caecocolic orifice. The results suggest, on the other hand, that enlargement of the caecocolic orifice was not successful in treating horses with hypertrophy of the caecal muscle layer in the whole caecum.
Evaluation of uniformity of morphological injury of the large colon following severe colonic torsion
Authors: van HOOGMOED L. , SNYDER J. R. , PASCOE J. R. , OLANDER H. J.
Published: June 2010

This report describes the evaluation of uniformity of morphological injury of the large colon following severe colonic torsion in 17 horses presented to the Veterinary Medical Teaching Hospital. In 16 horses, twist occurred at the colonic base and in 1 at the sternal and diaphragmatic flexure. Eleven of the 17 horses were subjected to euthanasia at surgery and 6 of 17 following surgical correction within 4 days postoperatively. The objective of this study was to determine if the degree of histological changes present at the pelvic flexure were uniformly distributed throughout the regions of the colon involved in cases of severe colonic torsion.
The medical management of eight horses with Grade 3 rectal tears
Authors: MAIR T. S.
Published: June 2010

Eight horses withGrade 3brectal tears of the peritoneal part of the rectum or small colon were treated by a combination of medical therapy and dietary manipulation. All of the horses developed septic peritonitis during the course of treatment. Medical therapy consisted of a combination of penicillin, gentamicin and flunixin meglumine administered parenterally, metronidazole administered orally and liquid paraffin administered by nasogastric tube. Some horses also received fluid and electrolyte therapy i.v., plasma and heparin i.v. All horses were maintained on a laxative diet. Six of the 8 horses recovered. Duration of therapy in the horses that survived was between 2 and 7 weeks. Three of the 6 horses that recovered developed a rectal diverticulum, which did not appear to cause any subsequent medical problems. In the 2 horses that died, theGrade 3rectal tear progressed to aGrade 4tear with subsequent faecal contamination of the abdomen. Manual evacuation of the cavity of the rectal tears during treatment and size of the tears were identified as possible causes for the progression of the disease in these 2 horses.
Forelimb tendon loading during jump landings and the influence of fence height
Authors: MEERSHOEK L. S. , SCHAMHARDT H. C. , ROEPSTORFF L. , JOHNSTON C.
Published: June 2010

Lameness in athletic horses is often caused by forelimb tendon injuries, especially in the interosseus tendon (TI) and superficial digital flexor tendon (SDF), but also in the accessory ligament (AL) of the deep digital flexor tendon (DDF). In an attempt to explain the aetiology of these injuries, the present study investigated the loading of the tendons during landing after a jump. In jumping horses, the highest forces can be expected in the trailing limb during landing. Therefore, landing kinematics and ground reaction forces of the trailing forelimb were measured from 6 horses jumping single fences with low to medium heights of 0.80, 1.00 and 1.20 m. The tendon forces were calculated using inverse dynamics and anin vitromodel of the lower forelimb. Calculated peak forces in the TI, SDF and DDF+AL during landing were 15.8, 13.9 and 11.7 kN respectively. The relative loading of the tendons (landing forces compared with failure forces determined in a separate study) increased from DDF to TI to SDF and was very high in SDF. This explains the low injury incidence of the DDF and the high injury incidence of the SDF. Fence height substantially influenced SDF forces, whereas it hardly influenced TI forces and did not influence AL strain. Reduction of fence height might therefore limit the risks for SDF injuries, but not for TI and AL injuries.
Effect of walking velocity on hindlimb kinetics during stance in normal horses
Authors: KHUMSAP S. , CLAYTON H. M. , LANOVAZ J. L.
Published: June 2010

The objectives of this study were to measure the effect of walking velocity on net joint moments and joint powers in the hindlimb during stance and to use the data to predict these variables at different walking velocities. Videographic and force data were collected synchronously from 5 sound horses walking over a force plate at a range of velocities. Force and kinematic data from 56 trials were combined using an inverse dynamic solution to determine net joint moments and joint powers. Analysis by simple regression and correlation (P<0.05, r2>0.30, r>0.50) showed that, in early stance, there were significant velocity‐dependent increases in the peak magnitudes of the following variables: extensor moment and positive power at the hip, flexor moment and positive power at the stifle, extensor moment, negative and positive power at the tarsus, and flexor moment and negative power at the fetlock. In late stance, there were significant velocity‐dependent increases in the peak magnitudes of the following variables: flexor moment at the hip, negative power at the stifle and flexor moment and positive power at the tarsus. As velocity increased, the hip showed an increase in energy generation, whereas the tarsus showed increases in both energy generation and absorption. It is concluded that an increase in walking velocity is associated with increases in peak magnitudes of the net joint moments and joint powers in the hindlimb; and that energy generation at the hip makes the largest contribution to the increase in velocity.
In vitro comparison between a DCP and external fixator for pancarpal arthrodesis in the dog
Authors: VIGUIER E. , ZNATY D. , MEDELCI M. , DEGUEURCE C.
Published: June 2010

Many clinical reports have previously documented the advantages of plates or external fixations but surgeons prefer to use plate for better acceptance by the owner, less dressing and a decreased rate of infection. In order to address complications of carpal surgery, infections, arthritis and osteomyelitis, external fixation is warranted. Twelve canine forelimbs, free of abnormality, were tested under compression to evaluate thein vitrobiomechanical behaviour of the normal carpus. This behaviour was compared with that of a stabilized carpus stabilised by panarthrodesis with either plates (8 hole 3.5 mm dynamic compression plate (DCP), or atype IIexternal fixator.

Deformation vs. load was recorded after compression with a testing machine in conjunction with a digital data acquisition system. Yield load, maximal load to failure and stiffness were then calculated. Variables were significantly greater for arthrodesis with external fixation and plates than for intact forelimbs. The stiffness and the MLF after stabilisation with plates or external fixators did not differ significantly. At MLF, fracture of the third metacarpus appeared with plates, whereas deformations of the pins and bars of the external fixators increased with load. Stabilisation with plate or external fixation allowed more load to failure than the intact carpus. The biomechanical behaviour of both methods of arthrodesis was identical during loading. However, after rupture, external fixation was more plastic. External fixation, which is less often used than plates for pancarpal arthrodesis, mainly due to the occurrence of sepsis, may be useful for arthrodesis of the carpus in big or active dogs.
Sciatic nerve transection in adult and young rats: abnormal EMG patterns during locomotion
Authors: GRAMSBERGEN A. , van EYKERN L. A. , MEEK M. F.
Published: June 2010

Transections of peripheral nerves usually lead to serious handicaps. In order to enhance insights into the poor functional recovery, we studied the effects of a unilateral sciatic nerve lesion in adult and young rats. Electromyographic (EMG) patterns of the tibialis anterior (a hindlimb flexor) and the gastrocnemius muscle (a hindlimb extensor) during walking were recorded after transecting the sciatic nerve at adult age and at the 10th postnatal day.

After recovery periods lasting up to 21 weeks, EMG patterns in the hindleg muscles during locomotion were highly abnormal, irrespective of the age at lesioning. Electromyographic bursts were markedly irregular and, generally, coactivation of these antagonists was observed during walking. Other evidence has shown that after peripheral nerve transection, nerves randomly reinnervate their target muscles and we conclude that the patterns of muscle activity may be associated with the properties of foreign, as well as genuine, motor nerves.

Behaviourally, walking patterns after a transection at adult age are markedly abnormal but, after transection at the 10th day, locomotion is much less disturbed. The finding of a discrepancy between a near normal walking pattern in rats operated on at a young age and severely disturbed EMG activity may be due to subtle readjustments in the force recruitment in the respective muscles, despite a random reinnervation by the sciatic nerve branches. These compensatory readjustments are particularly prominent after transection at an early age.
Determination of hoof mass and centre of mass from morphological measurements
Authors: ARABIAN A. K. , LANOVAZ J. L. , CLAYTON H. M.
Published: June 2010

Determination of net joint moments and powers requires accurate measurements of mass and centre of mass (COM) for the limb segments. The objective of this research was to develop regression equations for calculating mass and COM of the hoof segment that are applicable over a wide range of hoof morphologies. Ninety‐one hooves (mean ± s.d. 0.99 ± 0.50 kg) were weighed and the 3‐dimensional COM determined using a mass balance technique. Ten morphological variables were measured and used as independent variables in linear regressions with dependent variables of mass and centre of mass. The regression equation for mass was dependent upon coronet circumference, lateral height, solar length, solar width, heel height, toe height and base circumference (r2 = 0.978). Mediolateral COM was dependent only on solar length (r2 = 0.874). Dorsopalmar COM depended only upon solar length (r2 = 0.792) and vertical COM was defined only by lateral height (r2 = 0.377). Midlateral COM, measured at the midhoof wall along the tubules, was found to depend on coronet circumference, lateral height, toe length and toe height (r2 = 0.414). The large sample size and the inclusion of a variety of hoof masses and morphologies allow these results to be generalised to a wide range of the equine population. It was concluded that the mass and COM of the hoof segment can be estimated to a high degree of accuracy based on easily obtained morphological measurements.
Quantification of hoof deformation using optical motion capture
Authors: BURN J. F. , BROCKINGTON C.
Published: June 2010

Deformation of the hoof capsule occurs during stance phase as a result of loading by the distal phalanx. The objective of this study was to evaluate optical motion capture as a technique for measuring hoof deformation during locomotion, and to quantify the deformation of the dorsal wall during stance phase. The front left feet of 3 clinically sound horses were used for this study. The hoof wall was cleaned and 9 retroreflective markers were glued to the lateral and dorsal hoof wall, and shoe. Each horse was trotted in a straight line at constant speed while marker positions during stance phase were recorded at 240 frames/s using a 3‐dimensional (3‐D) motion capture system.

Similar patterns of hoof deformation were seen in all horses; the dorsal wall moved inwards towards the axis of the limb with displacement increasing proximally. Mean peak deformation varied between 0.17 and 0.92 mm in the dorsal hoof wall, and 0.18 and 0.76 mm in the lateral hoof wall. In all horses, movement of the shoe relative to the ground was <0.7 mm throughout stance phase and movement of the hoof relative to the shoe was <0.3 mm. Calibration using a micrometer indicated the motion capture system was accurate to <0.1 mm in the configuration used for the study.

This study showed that optical motion capture can be used to measure hoof deformation and successfully addresses some of the limitations of existing methods.
A method to determine mechanical energy conservation and efficiency in equine gait: a preliminary study
Authors: PREEDY D. F. , COLBORNE G. R.
Published: June 2010

Metabolic and mechanical energy costs of locomotion can be combined to calculate locomotor efficiency, which is the quotient of the mechanical energy and metabolic costs. The purpose of this pilot study was to evaluate the mechanical and metabolic energy costs of locomotion at a range of 7 trotting speeds (2.5 to 6.2 m/s) on a level treadmill. A single, sound Thoroughbred horse was modelled as a system of 15 linked segments incorporating all 4 limbs, head, neck and trunk. The horse performed a continuous incremental exercise test at increasing trotting speeds while VO2 was recorded using a breath‐by‐breath gas analysis system. Positional data were recorded concurrently at 100 Hz using a 2‐camera infrared kinematic system. Mechanical energy cost was calculated for 3‐6 strides per speed increment, and metabolic data were obtained during the last 15 s of each speed step. Mechanical energy cost increased linearly from 3.3 J/kg/m at 2.5 m/s to a value of 5.31 J/kg/m at 6.2 m/s, and the within‐subject variability was low at each of the speed steps. This analysis accounted for the important energy‐conserving mechanisms of energy exchange within and between segments of the link segment model. Within‐segment energy conservation remained approximately constant as speed increased, whereas between‐segment conservation increased from 1040 to 4502 J/stride. The combination of both metabolic and mechanical costs of locomotion yielded an inverted bell‐shaped curve of ‘apparent’ efficiency across the speed increments, with the maximum value occurring when metabolic cost was lowest at 3.8 m/s.
Gait transitions during unrestrained locomotion in dogs
Authors: BLASZCZYK J. W.
Published: June 2010

Gait transitions during long distance, unrestrained locomotion were studied in 22 mongrel dogs. Spatial and temporal limb movement parameters were collected and the phase relationships between limb movements based upon a 2‐dimensional (2‐D) gait diagram were computed. During most of the trials, the dogs trotted within a relatively narrow velocity range. Gait transitions were observed during radical changes of the movement velocity. In most cases the gait switches were abrupt and completed within 2 strides of the gait cycle. The dogs walked, depending on the animal size, within the upper velocity range of 0.93‐1.21 m/s. Most of the walk‐trot transitions were observed within this range. All of them had a typical pattern that involved changes of the phase shift between diagonal limb movements from 0.31 ± 0.02 (a typical value for a walking dog) down to 0.02 ± 0.03. These changes appeared abruptly within one stride cycle for each diagonal pair of limbs; therefore, the transition was completed in 2 strides of the gait cycle. The switch involved momentary shortening of the hindlimb amplitudes. During the next gait cycle, all limb movement amplitudes were reduced with a concomitant increase in limb movement frequencies.

In contrast to the clear border between the symmetrical gaits, the dogs switched to gallop at any speed within the trot range (most frequently between 1.5‐2.6 m/s). The transitions were usually completed within one stride of the diagonal limbs. In most cases, the switch from trot to gallop had a similar pattern; while maintaining synchronous movement of one diagonal pair of limbs, the other pair movement control was modified accordingly. The typical transition pattern involved the shortening of the swing phase in the front limb with simultaneous lengthening of the swing phase in the diagonal hindlimb. These transient modifications had their equivalent in the analogous limb movement amplitude changes. A mirror‐image pattern of phase changes was observed in the majority (82%) of the gallop‐trot transitions. Three of the dogs, however, besides the typical gallop‐trot switch, occasionally employed a second pattern of transition.
Kinematic analysis of the symmetry of limb movements in lame trotting horses
Authors: AUDIGIÉ F. , POURCELOT P. , DEGUEURCE C. , GEIGERT D. , DENOIX J. ‐M.
Published: June 2010

This study was undertaken to describe the symmetry of movements of fore‐ and hindlimbs in horses suffering from various spontaneous lamenesses. Two groups of horses were studied: 13 clinically sound horses and 24 lame horses. Using a 3‐dimensional (3‐D) kinematic analysis system, movements of both sides of each horse were recorded simultaneously while trotting on a track. The differences in motion between left and right homologous joints of each horse were quantified using symmetry indices based on an intercorrelation method. Symmetry indices obtained for each lame horse were then compared with those of sound horses. This comparison showed that the most sensitive lameness indicators were the symmetry indices of the vertical displacement of the proximal markers of the limbs. Symmetry indices of each lame horse were also compared with those of the other lame horses, using correlation coefficients to determine whether or not various lamenesses generate similar alterations of the locomotion symmetry. Values of these coefficients allowed 2 types of lameness to be distinguished. In 21 lame horses, the largest alterations in the symmetry of vertical movements were observed for the proximal markers of the limbs, which may reflect the supporting component of these lamenesses. In contrast, the asymmetries in vertical movements were more pronounced for the distal markers in 3 horses (one stringhalt and 2 carpal injuries), which may reflect the swinging component of these lamenesses. This cross‐correlation method can be implemented easily in a computer programme and may represent a first step in the development of an expert system.
Analysis of a radiographic technique for measurement of equine metacarpal bone shape
Authors: WALTER L. J. , DAVIES H. M. S.
Published: June 2010

Accuracy and limitations of a radiographic technique were established for measurement of metacarpal bone shape in horses. A radiographic index (RI) has been used to measure changes in third metacarpal (Mc3) bone shape in response to training in young racehorses. The aim of these experiments was to determine the effects of positioning of the radiographic equipment on RI measurements from lateromedial radiographs of a left ex vivo metacarpus. Repeatability of the RI measurement in left lateromedial and right mediolateral view Mc3s were evaluated. The width of the dorsal cortex (DC), palmar cortex (PC) and medulla (M) were measured at a position 25 mm distal to the nutrient foramen and the RI calculated where RI = [(DC+PC)/M] x [DC/PC]. The reference RI values were obtained from 12 standard lateromedial radiographs. Factors analysed included the optimum focus‐object distance, the angle at which the x‐ray machine was positioned, the distance of the cassette from the limb, and the horizontal angle and vertical tilt of the cassette. The RI values included within the confidence interval (mean ° 1.96 x s.d.) were considered sufficiently accurate. The optimum focus‐object distance was 1 m. Accurate measurements were obtained when the cassette was held as close to the limb as possible with the horizontal angle not exceeding 5°. The x‐ray machine needed to be orientated within 6° of the lateromedial plane. These findings suggest that the radiographic index can be used to measure Mc3 bone shape, providing there is accurate alignment of the x‐ray machine, cassette, and limb, with respect to one another.
Range of back movement at trot in horses without back pain
Authors: LICKA T. , PEHAM C. , ZOHMANN E.
Published: June 2010

The aim of this study was to establish basic reference data for evaluating 3‐dimensional movement of the equine back at the trot. In 22 mature horses without any clinical signs of back pain, the movement of the back was measured during trotting on a treadmill with a system for motion analysis. The position of the markers placed on the head, hooves, skin above the spinous processes of T5, T10, T16, L3 and on 2 of the sacral spines was recorded. The results of all movements were expressed in percent of the horse's height at its withers. At the trot, the maximum lateral movement at the head was 1.72% (s.d. 0.75). At T5 it was 3.15% (s.d. 0.84), at T10 1.99% (s.d. 0.64), at T16 1.85% (s.d. 0.65), at L3 1.89% (s.d. 0.62), at OS1 1.89% (s.d. 0.66) and at OS2 2.21% (s.d. 0.71). The maximum dorsoventral back movement was 4.06% (s.d. 1.14) at the head, 3.93% (s.d. 0.67) at T5, 4.46% (s.d. 0.85) at T10, 4.94% (s.d. 0.77) at T16, 4.91% (s.d. 0.74) at L3, 4.55% (s.d. 0.69) at OS1 and 4.33% (s.d. 0.69) at OS2.

The lateral movement of the back at trot is relatively small compared to the movement of the horse's back at stance or at walk, with the marker on T5 showing the widest lateral movement. The dorsoventral movement of the back is larger than the lateral movement, but the differences between single markers are small. The results of this study can be used as a comparison when investigating equine back pain.
Arthroscopic removal of fractures of the lateral malleolus of the tibia in the tarsocrural joint: A retrospective study of 13 cases
Authors: O'NEILL H. D. , BLADON B. M.
Published: June 2010

There is limited information on the treatment of lateral malleolus (LM) fractures in the horse, with no previously published case series for the outcome following arthroscopic removal of such fractures. This report reviews and evaluates findings of a retrospective study of 13 horses admitted to a private equine referral hospital over a 10 year period (1999–2009) that underwent arthroscopic removal of fractures of the LM. Hospital records were reviewed and details including patient history, aetiology of the fracture and limb affected, results of all diagnostic tests and surgical reports were documented. Performance information concerning Thoroughbred horses that went onto race post operatively was collected using an online database. Owners and trainers were contacted regarding the return to performance for non‐Thoroughbred cases or those that did not go onto race post operatively. Of the 13 horses presented, 12 were Thoroughbreds, 9 of which were National Hunt racehorses and 3 were Flat racehorses. The other horse in the study was used for general purpose riding. All cases presented with an acute unilateral fracture. Eleven of the 13 had >6 months post operative follow‐up and all were nonlame. Of the 12 Thoroughbreds, 10 have raced again, a total of 104 times (median 5 times). The median time from surgery to return to racing was 241 days (180–366 days). It is concluded that horses with fractures of the LM have an excellent prognosis for return to full athletic performance following arthroscopic debridement; and that arthroscopic fragment removal is an appropriate treatment method for fractures of the LM.
Duration of corneal anaesthesia following multiple doses and two concentrations of tetracaine hydrochloride eyedrops on the normal equine cornea
Authors: MONCLIN S. J. , FARNIR F. , GRAUWELS M.
Published: June 2010

Reasons for performing study: There is a clinical impression that tetracaine hydrochloride (THCl) eyedrops is a suitable topical anaesthetic in horses.

Objective: To determine the duration of corneal anaesthesia following instillation of multiple doses and 2 concentrations of THCl in 10 healthy horses.

Methods: The corneal touch threshold (CTT) was determined, in both eyes, before (basal CTT) and after application of one drop of 0.5%THCl, 2 drops at a 1 min interval of 0.5%THCl or one drop of 1%THCl. CTT was measured in mm every 5 min until complete recovery of the basal CTT. Treatments were separated by an interval of at least one week.

Results: Corneal sensitivity was significantly reduced from baseline values for 30, 60 and 50 min after application of one drop of 0.5%THCl, 2 drops of 0.5%THCl and one drop of 1%THCl, respectively. Mean maximal anaesthetic effects, corresponding to a CTT of 0 mm, lasted 5.5, 16 and 15.25 min and maximal anaesthetic effect was present in 55, 90 and 80% of eyes, 5 min after application of one drop of 0.5%THCl, 2 drops of 0.5%THCl and one drop of 1%THCl, respectively.

Conclusions: The application of a second drop or the use of more concentrated eyedrops significantly increases duration of both anaesthesia and maximal anaesthetic effect.

Potential relevance: Duration of corneal anaesthesia following tetracaine instillation was established enabling a better use when performing diagnostic and therapeutic procedures. Comparison of tetracaine with other ocular anaesthetics needs to be published in the future.
Determination of tear break‐up time reference values and ocular tolerance of tetracaine hydrochloride eyedops in healthy horses
Authors: MONCLIN S. J. , FARNIR F. , GRAUWELS M.
Published: June 2010

Reasons for performing study:Tetracaine hydrochloride (THCl) has been reported to cause irritation in dogs. In man, some topical anaesthetics have been shown to disrupt the tear film. Tear break‐up time (TBUT) is a useful test allowing an assessment of the quality of the precorneal tear film. Only one TBUT value has been reported in horses with no information on the technique used.

Objectives:To provide a method for performing the TBUT in horses and to report any side effects of a single application of THCl in clinically normal horses, particularly on the stability of the tear film.

Methods:InStudy 1, one drop of 0.5 or 1% THCl was applied to one eye of 20 horses divided in 2 groups. Treated eyes were assessed for the development of side effects 2.5 and 5 min after treatment. InStudy 2, the TBUT was measured in both eyes of 2 groups of 10 horses, before and 2.5 and 5 min after, instillation of one drop of either 0.5 or 1% THCl.

Results:No animals developed any ocular side effect after instillation. Basal TBUT was 8.3 ± 1.3 s. TBUT decreased from baseline 5 and 2.5 min after application of one drop of 0.5% THCl and one drop of 1% THCl, respectively.

Conclusions:A technique to measure the TBUT in healthy horses is described and normal range values that could be used as a reference were obtained.

Potential relevance:THCl is well tolerated in horses but lowers the TBUT.
Nanoscale Tunable Reduction of Graphene Oxide for Graphene Electronics
Authors: Wei Zhongqing , Wang Debin , Kim Suenne , Kim Soo-Young , Hu Yike , Yakes Michael K. , Laracuente Arnaldo R. , Dai Zhenting , Marder Seth R. , Berger Claire , King William P. , de Heer Walter A. , Sheehan Paul E. , Riedo Elisa
Published: June 2010

Writing Conductive Lines with Hot Tips

The interface within devices between conductors, semiconductors, and insulators is usually created by stacking patterned layers of different materials. For flexible electronics, it can be advantageous to avoid this architectural constraint. Graphene oxide, formed by chemical exfoliation of graphite, can be reduced to a more conductive form using chemical reductants.

Wei
et al.

(p.
1373
) now show that layers of graphene oxide can also be reduced using a hot atomic force microscope tip to create materials comparable to those of organic conductors. This process can create patterned regions (down to 12 nanometers in width) that differ in conductivity by up to four orders of magnitude.
Focal Lesions of Human Hippocampal CA1 Neurons in Transient Global Amnesia Impair Place Memory
Authors: Bartsch T. , Schönfeld R. , Müller F. J. , Alfke K. , Leplow B. , Aldenhoff J. , Deuschl G. , Koch J. M.
Published: June 2010

Lost in a Maze

In rodents, hippocampal CA1 neurons play a pivotal role in the processing of spatial memory. However, the contribution of CA1 neurons in the human hippocampus to spatial memory has been difficult to establish.

Bartsch
et al.

(p.
1412
) studied a group of patients with transient global ischemia, a condition that lasted for at most a few hours and was followed by complete recovery. The patients were tested on a range of complex neuropsychological instruments, including virtual reality, during the ischemic attack. A striking impairment was observed in simple spatial navigation to a hidden target. The performance of the patients was correlated with the duration of the transient global ischemia, as well as with the size of the CA1 lesions.
Defective Cross-Presentation of Viral Antigens in GILT-Free Mice
Authors: Singh Reshma , Cresswell Peter
Published: June 2010

Not GILT-Free Processing

CD8
+
T cells respond to infections by recognizing peptide antigens bound to major histocompatability complex class I (MHC class I) protein expressed on the surface of antigen-presenting cells (APCs). Because MHC class I can only present intracellular antigens, antigen cross-presentation is important for responses to viruses that do not directly infect APCs. Antigen cross-presentation occurs when APCs acquire antigens by phagocytosis of dying virally infected cells and present them to CD8
+
T cells. After internalization, antigens must enter the cytosol for processing by the proteasome.
Singh and Cresswell
(p.
1394
) now show that GILT (gamma-interferon–inducible lysosomal thiolreductase) is required for cross-presentation in mice of disulfide-containing viral antigens. In mice lacking GILT, the CD8
+
T cell response to antigens derived from disulfide-rich proteins was substantially impaired after influenza A or herpes simplex virus 1 infection. Thus, cross-presentation of some antigens requires an early processing step prior to proteasomal degradation in the cytosol and subsequent MHC class I loading.
Periodic, Chaotic, and Doubled Earthquake Recurrence Intervals on the Deep San Andreas Fault
Authors: Shelly David R.
Published: June 2010

Reconsidering Recurrence

The very long times between major earthquakes on known susceptible faults make estimating a long-term recurrence interval difficult. Deep, low-frequency earthquakes happen much more frequently and thus provide a natural setting for studying earthquake occurrence.
Shelly
(p.
1385
) examined the timing of over 900 tiny earthquakes along a well-studied portion of the San Andreas Fault during a span of 8.5 years. The recurrence intervals between these microearthquakes, which roughly occurred on 3- and 6-day cycles, were sensitive to larger nearby events. For example, following the Parkfield earthquake in 2004, the 3-day cycle shortened and the 6-day cycle disappeared. If large-earthquake recurrence intervals are similarly variable over time, it will be extremely difficult to predict future damaging earthquakes from a short historical record.
Frontier Research in Europe
Authors: Nowotny Helga
Published: June 2010

Next month, the Fourth Euroscience Open Forum (ESOF 2010) opens in Torino, Italy, to discuss the frontiers of science and technology in Europe and to stimulate policies that bridge the gap between science and society. In this context, the current European research landscape can hardly be imagined without the innovative funding programs of the European Research Council (ERC), which has selected its 1000th grantee just over 3 years after its launch. As the new president of the ERC, I am particularly pleased to continue building on past achievements while preparing for the challenges ahead.
Think Vesicular Chloride
Authors: Smith Andrew J. , Schwappach Blanche
Published: June 2010

Transporters that import chloride ions in exchange for the export of protons control the function of intracellular vesicles in mammalian cells.
fMRI Lie Detection Fails a Legal Test
Authors: Miller Greg
Published: June 2010

Lie-detection technology that uses functional magnetic resonance imaging scans of brain activity is not yet ready for use in the courtroom, a federal magistrate judge in Tennessee decided last week.
Obama's Nominee to Lead NSF Lauded for Science and Management Skills
Authors: Mervis Jeffrey
Published: June 2010

Subra Suresh, dean of engineering at the Massachusetts Institute of Technology, was nominated last week to become the next director of the National Science Foundation.
Merger to Create New Voice for European Science
Authors: Clery Daniel
Published: June 2010

Two pan-European bodies have begun planning a merger. The aim is to create a single, and more powerful, voice for the national science funding agencies that control some €25 billion annually—by far the largest slice of public money available to the region's scientists.
The Prickly Side of Oxytocin
Authors: Miller Greg
Published: June 2010

In experiments reported in this week's issue of
Science
, subjects who received a dose of the social-bonding hormone oxytocin behaved more altruistically toward members of their own group. Yet they also displayed more "defensive aggression" toward outsiders, preemptively punishing members of a competing group when their own group was in danger of suffering a heavy loss.
After Legal Threat and 3-Year Delay, Paper on Psychopathy to Appear—Maybe
Authors: Travis John
Published: June 2010

Have fears of "libel tourism" kept a controversial psychology paper on psychopaths from seeing the light of day for more than 3 years after its acceptance by a journal? One of the authors believes that's the case.
Reaping the Benefits of Biomedical Research: Partnerships Required
Authors: Portilla Lili M. , Alving Barbara
Published: June 2010

The National Institutes of Health are exploring multiple ways in which to increase the efficiency of the translational process.
On or Off Target: Mutations, Models, and Predictions
Authors: Garraway Levi A. , Hahn William C.
Published: June 2010

An elegant biochemical study reconciles some of the confusing aspects of the discovery and development of anticancer drugs that inhibit the RAF protein kinase.
Comparison of BD Phoenix, Vitek 2, and MicroScan Automated Systems for Detection and Inference of Mechanisms Responsible for Carbapenem Resistance in
Enterobacteriaceae
Authors: Woodford Neil , Eastaway Anne T. , Ford Michael , Leanord Alistair , Keane Chloe , Quayle Reinhard M. , Steer Jane A. , Zhang Jiancheng , Livermore David M.
Published: June 2010

We assessed the ability of three commercial systems to infer carbapenem resistance mechanisms in 39 carbapenemase-producing and 16 other carbapenem-resistant
Enterobacteriaceae
. The sensitivity/specificity values for “flagging” a likely carbapenemase were 100%/0% (BD Phoenix), 82 to 85%/6 to 19% (MicroScan), and 74%/38% (Vitek 2), respectively. OXA-48 producers were poorly detected, but all systems reliably detected isolates with KPC and most with metallo-carbapenemases.
Invasive Serotype 1
Streptococcus pneumoniae
Outbreaks in the South Pacific from 2000 to 2007
Authors: Le Hello S. , Watson M. , Levy M. , Marcon S. , Brown M. , Yvon J. F. , Missotte I. , Garin B.
Published: June 2010

In New Caledonia, Wallis and Futuna, and French Polynesia, an active surveillance system was established to monitor pneumococcal serotype prevalence between 2000 and 2007. The most prevalent serotype was serotype 1, which belonged to the major clonal complex sequence type 306 (ST306) and was responsible for invasive pneumococcal disease outbreaks.
Roseomonas mucosa
Isolated from Bloodstream of Pediatric Patient
Authors: Bard J. Dien , Deville J. G. , Summanen P. H. , Lewinski M. A.
Published: June 2010

We report a case of catheter-related bacteremia associated with
Roseomonas mucosa
isolated from an immunocompromised pediatric patient with a history of multiple episodes of urinary tract infection and bacteremia.
Rapid Detection of
Trypanosoma cruzi
in Human Serum by Use of an Immunochromatographic Dipstick Test
Authors: Reithinger Richard , Grijalva Mario J. , Chiriboga Rosa F. , Alarcón de Noya Belkisyolé , Torres Jaime R. , Pavia-Ruz Norma , Manrique-Saide Pablo , Cardinal Marta V. , Gürtler Ricardo E.
Published: June 2010

We evaluated a commercially available immunochromatographic dipstick test to detect
Trypanosoma cruzi
infection in 366 human serum samples with known serological results from Argentina, Ecuador, Mexico, and Venezuela. One hundred forty-nine of 366 (40.7%) and 171/366 (46.7%) samples tested positive by dipstick and serology, respectively. Dipstick sensitivity was calculated to be 84.8% (range between countries, 77.5 to 95%), and specificity was 97.9% (95.9 to 100%).
Neutralization of Human Respiratory Syncytial Virus Infectivity by Antibodies and Low-Molecular-Weight Compounds Targeted against the Fusion Glycoprotein
Authors: Magro Margarita , Andreu David , Gómez-Puertas Paulino , Melero José A. , Palomo Concepción
Published: June 2010

Human respiratory syncytial virus (HRSV) fusion (F) protein is an essential component of the virus envelope that mediates fusion of the viral and cell membranes, and, therefore, it is an attractive target for drug and vaccine development. Our aim was to analyze the neutralizing mechanism of anti-F antibodies in comparison with other low-molecular-weight compounds targeted against the F molecule. It was found that neutralization by anti-F antibodies is related to epitope specificity. Thus, neutralizing and nonneutralizing antibodies could bind equally well to virions and remained bound after ultracentrifugation of the virus, but only the former inhibited virus infectivity. Neutralization by antibodies correlated with inhibition of cell-cell fusion in a syncytium formation assay, but not with inhibition of virus binding to cells. In contrast, a peptide (residues 478 to 516 of F protein [F478-516]) derived from the F protein heptad repeat B (HRB) or the organic compound BMS-433771 did not interfere with virus infectivity if incubated with virus before ultracentrifugation or during adsorption of virus to cells at 4°C. These inhibitors must be present during virus entry to effect HRSV neutralization. These results are best interpreted by asserting that neutralizing antibodies bind to the F protein in virions interfering with its activation for fusion. Binding of nonneutralizing antibodies is not enough to block this step. In contrast, the peptide F478-516 or BMS-433771 must bind to F protein intermediates generated during virus-cell membrane fusion, blocking further development of this process.
CD4 T-Cell Help Programs a Change in CD8 T-Cell Function Enabling Effective Long-Term Control of Murine Gammaherpesvirus 68: Role of PD-1-PD-L1 Interactions
Authors: Dias Peter , Giannoni Francesca , Lee Lian Ni , Han Dongun , Yoon Sorah , Yagita Hideo , Azuma Miyuki , Sarawar Sally R.
Published: June 2010

We previously showed that agonistic antibodies to CD40 could substitute for CD4 T-cell help and prevent reactivation of murine gammaherpesvirus 68 (MHV-68) in the lungs of major histocompatibility complex (MHC) class II−/−(CII−/−) mice, which are CD4 T cell deficient. Although CD8 T cells were required for this effect, no change in their activity was detectedin vitro. A key question was whether anti-CD40 treatment (or CD4 T-cell help) changed the function of CD8 T cells or another cell typein vivo. To address this question, in the present study, we showed that adoptive transfer of CD8 T cells from virus-infected wild-type mice or anti-CD40-treated CII−/−mice caused a significant reduction in lung viral titers, in contrast to those from control CII−/−mice. Anti-CD40 treatment also greatly prolonged survival of infected CII−/−mice. This confirms that costimulatory signals cause a change in CD8 T cells enabling them to maintain effective long-term control of MHV-68. We investigated the nature of this change and found that expression of the inhibitory receptor PD-1 was significantly increased on CD8 T cells in the lungs of MHV-68-infected CII−/−, CD40−/−, or CD80/86−/−mice, compared with that in wild-type or CD28/CTLA4−/−mice, correlating with the level of viral reactivation. Furthermore, blocking PD-1-PD-L1 interactions significantly reduced viral reactivation in CD4 T-cell-deficient mice. In contrast, the absence of another inhibitory receptor, NKG2A, had no effect. These data suggest that CD4 T-cell help programs a change in CD8 T-cell function mediated by altered PD-1 expression, which enables effective long-term control of MHV-68.
MINIMALITY OF AFFINE LAGRANGIAN SUBMANIFOLDS IN COMPLEX EQUIAFFINE SPACES
Authors: OPOZDA BARBARA
Published: June 2010

The notion of complex equiaffine manifolds is an affine generalization of Calabi–Yau manifolds. Similarly as in the Riemannian case the minimality of affine Lagrangian submanifolds in complex equiaffine spaces can be studied via calibrations, phase functions and variational formulas.