PubMed Health⌕ Search

Biomedical subjects

R C Murray

Publications and source records attributed to R C Murray.

24 records · Page 2Linked to original sources
PubMed1994

Acute effects of perineural administration of sodium hyaluronate on palmar digital neurectomy sites in horses.

Biaxial palmar digital neurectomy of all limbs was performed on 6 mixed-breed castrated adult male horses, using a standard guillotine method. Using a Teflon catheter, 20 mg (2 ml) of sodium hyaluronate (group 1), 2 ml of phosphate-buffered saline solution (group 2), or catheter placement with no infusion (group 3) was applied to 4 (group 1) or 2 (groups 2 and 3) of 8 incisions/horse. Treatments were administered after closure of the neurectomy incision, and the catheter was removed. Horses were evaluated daily for 1 week, then weekly over a 9-week period for evidence of lameness, swelling, and ultrasonographic changes. On week 9, horses were euthanatized and neurectomy sites were removed en bloc for histologic evaluation of axonal regrowth, inflammation, and fibrosis. Neither lameness nor sign of painful neuroma was observed clinically in any of the horses. Neurectomy eliminated cutaneous heel sensation in all limbs for the duration of the study. Swelling was evident at all neurectomy sites. There were no significant differences between treatment sites for measurement of pastern circumference or ultrasonographic evaluation of incisional swelling. Foci of ultrasonographic hyperechogenicity increased over time, but there was no significant difference in hyperechogenicity between treatment groups. Histologic evidence of neuroma formation was observed at all sites. Morphometric assessment of neuroma cross-sectional areas revealed no significant difference between the groups, as did subjective histologic assessment of neuroma density and fibrous tissue content.(ABSTRACT TRUNCATED AT 250 WORDS)

Administration, Topical↗
PubMed1994

Incarceration of the jejunum in the epiploic foramen of a four month old foal.

A 4-month Arabian filly presented for abdominal pain of 30 hours duration was found to have tachycardia, tachypnea, congested mucous membranes and gross abdominal distension. Further examination disclosed gastric reflux and small intestinal distension. Dehydration, prerenal azotemia, electrolyte abnormalities and metabolic alkalemia were observed. There was a progressive nonresponse to analgesic medication and deterioration in the foal's physiologic condition consistent with a small intestinal strangulating obstruction. Surgical exploration was declined. Necropsy examination revealed incarceration of the mid-jejunum in the epiploic foramen with proximal jejunal distension. This case is remarkable as the first report of entrapment of the jejunum in the epiploic foramen of a young foal.

Abdominal Pain↗
PubMed1992

Molecular cloning of a gene involved in methotrexate uptake by DNA-mediated gene transfer.

A methotrexate-resistant Chinese hamster ovary cell line deficient in methotrexate uptake has been complemented to methotrexate sensitivity by transfection with DNA isolated from a wild-type Chinese hamster ovary genomic cosmid library. Primary and secondary transfectants, which contain a limited number of cosmid sequences, have been shown to regain methotrexate sensitivity and to take up methotrexate. Furthermore, the DNA from three cosmid clones, isolated from a primary methotrexate-sensitive transfectant, after transfection rescued the methotrexate-resistant phenotype at a high frequency. Restriction endonuclease analysis of the DNA of these cosmid clones indicated that they overlapped extensively and shared two regions of Chinese hamster ovary DNA of 6.6 kb and 20.6 kb. These observations indicate that a gene involved in methotrexate uptake is contained in its entirety within one of these regions. This is the first report of the functional molecular cloning of a gene involved in methotrexate uptake. A general strategy is also described for screening large cosmid libraries from primary transfectants.

Animals↗
PubMedDate not supplied

Application of a hook plate for management of equine ulnar fractures.

Closed fractures of the proximal aspect of the ulna were repaired in 10 horses younger than or equal to 6 months of age by application of a hook plate using a tension band principle. Ulnar fractures were classified as type 1A (2 horses), type 1B (4 horses), type 2 (1 horse), type 3 (1 horse), and type 4 (2 horses); all fractures had displacement of a proximal fragment. Complications were implant deformation (4 horses), screw pullout (1 horse), osseous sequestration (1 horse), ulnar fracture through a hole used to apply a tension device (1 horse), and metacarpophalangeal deformity associated with a displaced anconeal fragment (1 horse). Hook deformation was likely associated with failure to insert screws in all of the proximal holes of the plate and also in two horses, possibly with difficult recovery from anesthesia. Seven horses were discharged from the hospital and were being used for athletic activities. Insertion of the hook through the tendon of the triceps muscle and incorporation of the fragment within the hook can be used to effectively reduce and stabilize a fragment that might otherwise not hold screws.

Animals↗
PubMedDate not supplied

Biomechanical comparison of the Herbert and AO cortical bone screws for compression of an equine third carpal bone dorsal plane slab osteotomy.

OBJECTIVE: To assess feasibility of insertion of 4.5-mm Herbert cannulated bone screws (HS) using fluoroscopic guidance and compare the mechanical shear strength of these HS and 4.5-mm AO cortical bone screws (AO) for fixation of dorsal plane slab osteotomies in equine cadaver third carpal bones (C3). ANIMALS OR SAMPLE POPULATION: Eight equine cadavers. METHODS: Bone mineral composition and density of contralateral C3 were confirmed to be equivalent using dual-energy x-ray absorptiometry. A standard 10-mm C3 slab osteotomy was reduced using HS or AO instrumentation under fluoroscopic guidance. Specimens were loaded in shear until failure, using a materials testing apparatus. RESULTS: HS and AO instrumentation allowed accurate reconstruction of the osteotomy, but there was difficulty encountered seating the HS proximal self-tapping threads. There was no significant difference in maximal load to failure, stiffness, or mode of failure of constructs created with the HS and AO screws. CONCLUSIONS: Use of 4.5-mm HS for repair of C3 radial facet, dorsal plane slab fractures may result in a mechanically comparable fixation to a repair using a 4.5-mm AO. Equine dorsal C3 may be too dense, however, to allow placement of the proximal self tapping threads of the HS without potentially excessive application of torque to the screw itself. CLINICAL RELEVANCE: Dorsal plane, radial facet slab fractures of the equine C3 are a significant clinical problem. Accurate reconstruction and stabilization are necessary for return to athletic function.

Absorptiometry, Photon↗