The effect of initiation of exercise training in young horses on vitamin K status

Twelve Quarter Horses, 18 to 24 mo of age and having an average body weight of 460+/-12 kg, were randomly assigned to one of two exercise treatments (control and exercise) to study the effect of initiation of exercise training in young horses on vitamin K status. The control treatment consisted of hand-walking the horses 7 min/d and 5 d/wk for 180 d. Exercise consisted of the following treadmill exercise regimen: 2 min at 4.5 to 5.4 m/s, 3 min at 13.4 to 14.3 m/s, and 2 min at 4.5 to 5.4 m/s on 5 d/wk for 180 d. Both groups were allowed free access to brome grass hay (273 mg of phylloquinone/100 g) individually. Additionally, the exercise group was fed .45 kg of a grain-mix concentrate (40 mg of phylloquinone/100 g) on the days they were exercised. Jugular venous blood samples were collected at d 0, 30, 60, 90, 120, 150, and 180. Blood samples were analyzed for total serum osteocalcin and vitamin K status via the hydroxyapatite binding capacity of serum osteocalcin calculated as follows: Hydroxyapatite binding capacity of serum osteocalcin = [(total serum osteocalcin - serum osteocalcin following extraction of serum with hydroxyapatite)/total serum osteocalcin] x 100. All horses were killed with an overdose of sodium pentobarbital on d 180. Computed tomographic osteoabsorptiometry was used to measure relative bone density distribution on the surface of the distal radial carpal bone, proximal third carpal bone, and the distal third metacarpal condyle. Relative bone density distribution was measured in Hounsfield units and categorized as low-, medium-, and high-density bone corresponding to 800 to 1,199, 1,200 to 1,299, and 1,300 to 3,000 Hounsfield units, respectively. Carpal and metacarpophalangeal joints were assigned a score of 0 (normal) to 3 (severe) that reflected the presence and severity of joint lesions. Hydroxyapatite binding capacity of serum osteocalcin and serum osteocalcin were unchanged over the 180-d period in both groups. Exercised horses had a higher percentage of high density bone (P < .01) and a lower percentage of low density bone (P < .01) on the surface of the third metacarpal condyle and a higher cumulative gross lesion score (P < .01) in the metacarpophalangeal joint than controls. There were no differences between treatments in relative bone density distribution in the carpal bones, or cumulative gross lesion score of the carpal joints. No significant correlation was present between the serum measures, osteocalcin and hydroxyapatite binding capacity of serum osteocalcin, and the bone measures, relative bone density distribution and joint gross lesion score.     

Development of probe-based ultraweak chemiluminescence technique for the detection of a panel of four oxygen-derived free radicals and their applications in the assessment of radical-scavenging abilities of extracts and purified compounds from food and herbal preparations

We report here the development of a probe-based ultraweak chemiluminescence (uwCL) method capable of detecting a panel of four oxygen-derived free radicals (ODFRs) including superoxide (O2-), hydrogen peroxide (H2O2), hydroxyl radical (*OH), and peroxyl radical (ROO*) using different probes specific for these radicals performed by the same uwCL analyzer. The selected radical-generating systems and their corresponding uwCL-probing emitters were validated. These ODFR-detecting systems were subsequently utilized by us to assess the radical-scavenging ability (RSA) of a variety of extracts and purified constituents derived from foods and herbal preparations. Our approach for assessing RSA for these constituents is based on the suppression of uwCL generated by each ODFR, and the degrees of inhibition have been shown to be dose-dependent. For this reason, the estimation of IC50 for each testing compound can be obtained from the curve constructed based on the percent of inhibitions of uwCL versus the concentrations of the compound tested. To illustrate the practical applications of our devised methodology, data for comparative studies of RSA activities of fermented extracts of Cordeceps sinensis, purified methylgallate isolated from Toona sinesis, resveratrol purified from grape seeds, plus epimedin C from the aerial part of the Epimedium plant (yinyanghuo) are to be presented.     

Evaluation of the diffusion of corticosteroids between the distal interphalangeal joint and navicular bursa in horses

OBJECTIVE: To determine whether clinically effective concentrations of methylprednisolone or triamcinolone can be achieved in the navicular bursa after injection of methylprednisolone acetate (MPA) or triamcinolone acetonide (TA) into the distal interphalangeal joint (DIPJ) and whether clinically effective concentrations of these drugs can be achieved in the DIPJ after injecting the navicular bursa with the same doses of MPA or TA. ANIMALS: 32 healthy horses. PROCEDURES: Horses in groups 1 through 4 received 40 mg of MPA in the DIPJ, 10 mg of TA in the DIPJ, 40 mg of MPA in the navicular bursa, and 10 mg of TA in the navicular bursa, respectively. Concentrations of corticosteroids that diffused into the adjacent synovial structure were determined. RESULTS: For group 1, injection of MPA into the DIPJ yielded a mean +/- SD concentration of 0.24 +/- 0.072 microg of methylprednisolone/mL in the navicular bursa. For group 2, injection of TA into the DIPJ yielded 0.124 +/- 0.075 microg of triamcinolone/mL in the navicular bursa. For group 3, injection of MPA into the navicular bursa yielded 0.05 +/- 0.012 microg of methylprednisolone/mL in the DIPJ. For group 4, injection of TA into the navicular bursa yielded 0.091 +/- 0.026 microg of triamcinolone/mL in the DIPJ. CONCLUSIONS AND CLINICAL RELEVANCE: A clinically effective concentration of methylprednisolone or triamcinolone diffused between the DIPJ and navicular bursa after intra-articular or intrabursal injection, which would justify injection of the DIPJ with MPA or TA to ameliorate inflammation of the navicular bursa.     

Cartilage canals in the medial coronoid process of young Golden Retrievers

The aim of the study was to establish the location of cartilage canals in the medial coronoid process (MCP) of the ulna of young Golden Retrievers, a breed that is predisposed to fractures of the medial coronoid process (FMCP). To determine whether the presence of cartilage canals could be associated with the predilection site of FMCP, the right elbows of nine young Golden Retrievers (aged 4, 6, 8, 10, 13, 16, 18, 22 and 24 weeks) were dissected and, with no prior decalcification, the formaldehyde-fixed MCPs were embedded in methylmethacrylate. The entire MCPs were serially sectioned in the frontal plane from cranial to caudal and the sections (5 microm) were routinely stained. Between the ages of 5 and 10 weeks, three main cartilage canals were visible--medial, central and lateral. All originated from the periosteum of the distal parts of the MCP and ended proximally under the articular cartilage. Branches of the main canals were seen more cranially and caudally. At the age of 13 weeks, the central canal was absent, and the remaining canals showed a smaller diameter. From 16 weeks onwards, no cartilage canals were seen. No direct relationship could be established between the predilection site of FMCP (lateral part of the MCP) and the presence/absence of cartilage canals, since both medial and lateral canals disappeared at the same age. Further research is needed to elucidate the pathogenesis of FMCP.     

Limited open reduction and stabilization of sacroiliac fracture-luxations using fluoroscopically assisted placement of a trans-iliosacral rod in five dogs

Objective— To describe percutaneous fluoroscopically assisted placement of a trans-iliosacral rod to stabilize sacroiliac fracture-luxations after limited open reduction.
Study Design— Retrospective clinical case series.
Animals— Dogs (n=5) with sacroiliac fracture-luxations.
Methods— Medical records and radiographs were reviewed to evaluate implant placement, fracture reduction, pelvic canal diameter ratio, maintenance of reduction, implant stability, assessment of union, and to identify any complications. Owners were contacted to obtain long-term assessment of limb function.
Results— Dogs weighed between 6 and 31 kg. Trans-iliosacral rods were placed correctly traversing the sacral body. Mean (±SD) percent reduction of the sacroiliac joint was 92.9±6.6%. Pelvic canal diameter ratio did not differ significantly between time periods. With the exception of 1 dog, which died in the early postoperative period, all sacroiliac fracture-luxations healed without appreciable complications. Three dogs were sound and 1 dog had a subtle lameness at final physical and radiographic examination (mean±SD: 217±205 days). Owners assessed their dog's limb function (mean±SD: 355±205 days) as good or excellent.
Conclusions— Trans-iliosacral rods can be accurately placed using intraoperative fluoroscopy after limited open reduction of sacroiliac fracture-luxations. Trans-iliosacral rods provided bilateral secure fixation, allowed early weight-bearing and dogs consistently had good long-term clinical results.
Clinical Relevance— Trans-iliosacral rods are suitable implants for the stabilization of sacroiliac fracture-luxations, particularly in dogs with bilateral fracture-luxations and/or concurrent musculoskeletal injuries.     

Enclosed bark as a pollen trap

Counts were made of pollen in traps formed by enclosed bark in two remnants of bristlecone pine, Pinus aristata Engelm., from the White Mountains of east-central California. The traps, dated by tree-rings at A.D. 350 and 1300 B.C., contained a major complex of pine-sagebrush pollen and traces of other species, representing the equivalent of the present vegetation.     

Photometry from voyager 2: initial results from the uranian atmosphere, satellites, and rings

The Voyager 2 photopolarimeter successfully completed the Uranus encounter, acquiring new data on the planet's atmosphere, its principal satellites, and its ring system. Spatially resolved photometry of the atmosphere at 0.27 micrometer shows no enhancement in absorption toward the pole, unlike the case for Jupiter and Saturn. Stellar occultation measurements indicate the temperature at the 1-millibar level over the north pole is near 90 kelvins. The geometric albedos of the five large satellites of Uranus were measured at 0.27 and 0.75 micrometer and indicate the presence of low albedo, spetrally flat absorbing material. Titania seems to have a fluffy surface, as indicated by its phase curve. The nine ground-based rings were detected, and their internal structure, optical depths, and positions were determined. The sharp edges of the in ring made it possible to measure its edge thickness (less than 150 meters) and particle sizes (less than 30 meters); little or no dust was detcted. New narrow rings and partial rings (arcs) were measured, and the narrow component of the eta ring was found to be discontinuous.