Puncture Wounds of the Navicular Bursa in 38 Horses A Retrospective Study

The medical records of 38 horses with puncture wounds of the navicular bursa were reviewed. Only 12 horses had a satisfactory outcome (breeding or riding). Of the remaining 26 horses, 19 were euthanized, five were sold due to persistent severe lameness, one died, and one was lost to long-term follow-up. Different combinations of conservative management prior to surgical debridement and drainage of the navicular bursa were unsuccessful in resolving the condition. Horses that were treated surgically within 1 week of the injury and had a hind leg affected had the best chance of a satisfactory outcome. Additional wound debridement was necessary in 15 horses after initial surgical treatment. The most common complications encountered were navicular bone osteomyelitis and sepsis of the deep digital flexor tendon. Thirteen of 14 horses that had rupture of the deep digital flexor tendon and subluxation of the distal interphalangeal joint had an unsatisfactory outcome. One mare subsequently developed ankylosis of the distal interphalangeal joint and was a useful brood mare. Two horses that had biaxial palmar digital neurectomy because of persistent lameness were later euthanized because of navicular bone fracture and rupture of the deep digital flexor tendon. Results from limited numbers of bacterial cultures and antibiotic sensitivities suggest that penicillin and an aminoglycoside antibiotic should be used as initial antibiotic therapy. Immediate surgical debridement and appropriate antibiotic treatment are recommended as the minimum therapy for penetrating wounds of the navicular bursa in horses.     

Effect of 2,4,5-T and picloram on the regeneration of blackberry (Rubus procerus P.J. Muell) from root segments

The formation of roots and shoots on root segments of Rubus procerus P.J. Muell was prevented by soaking the segments for 24 h in a 10^?4M solution of 2,4,5-T or a 10^?5M solution of picloram. Shoot numbers were significantly increased after treatment with 10^?9M and 10^?10M 2,4,5-T, but picloram did not cause a significant increase in shoot numbers. Measurement of the concentration of 2,4,5-T in the extracambial tissue showed that roots treated with 10^?4M 2,4,5-T contained 5× 10^?8 mmole 2,4,5-T per mg dry weight, and by extrapolation, roots treated with 10^?9M 2,4,5-T contained 2× 10^?10 mmole/mg dry weight. Action du 2,4,5-T et du piclorame sur la régénération de la ronce (Rubus procerus P.J. Muell) è partir de fragments de racines La formation de racines et de tiges è partir de fragments de racines dc Ruhus procerus P.J. Muell a été supprimée par trempage des fragmenls pendant 24 heures dans une solution a 10^?4M et de 2.4,5-T, ou dans une solution 10^?5M de piclorame. Le nombre de pousses s'est accru significativement après traitement avec le 2,4,5.-T è 10^?9M et 10^?10M, mais le piclorame n'a pas provoqué d'accroissemcnt significatif du nombre de pousses. La mesure de la concentration de 2,4,5-T dans le tissu extra-cambial a montré que les racines trailées avec du 2,4,5-T è 10^?4M contenaient 5×10^?8 mmole de 2.4,5-T par mg de poids sec et par extrapolation, quc les racines traitées avec du 2,4,5-T k 10^?9M devaient contenir 2 × 10^?12 mmole/mg de poids sec. Die Wirkiing von 2,4,5-T und Picloram auf den Wuchs der Wurzehegmenten von Bromheeren (Rubus procerus P.J. Muell). Die Bildung von Wurzeln und Sprossen aus Wurzelsegmen-ten von Ruhu.i procerus P.J. Muell wurde durch 24-stündiges Einlegen der Wurzelstücke in 10^?4M 2,4,5-T bzw 10^?5M Picloram verhindert. Die Anzahl neugebiideter Sprosse wurde nach Einlegen in 10^?9M und 10^?10M 2,4,5-T, nicht jedoch durch Picloram, signifikant erhöht. Im extracambialen Gewebe von Wurzeln, die mit 10^?4M 2,4,5-T behand-elt worden waren, wurden 5×10^?8mMol 2,4,5-T je mg Trockengewiclu bestimmt. Durch Extrapolation wurde ermittclt. dass mit 10^?9M 2,4,5-T behandelte Wurzeln 2× 10^?12mMol/mg Trockengewicht cnthielten.     

Distribution of Topical Agents in the Frontal Sinuses and Nasal Cavity of Dogs: Comparison Between Current Protocols for Treatment of Nasal Aspergillosis and a New Noninvasive Technique

To document and compare patterns of distribution of topically applied antifungal medication, heads from 42 canine cadavers were assigned to seven treatment groups which included two current surgical treatment protocols for nasal aspergillosis, and a new, noninvasive method. Catheters (8 Fr) were placed through trephine holes into the frontal sinuses and nasal cavity. Dilute dye was injected through the catheters and the heads were sectioned sagittally. The administration of 5 mL of dye into the lateral frontal sinus and nasal cavity (group IA, 10 mL total) was compared with 25 mL injected through catheters placed bilaterally in the lateral frontal sinus and nasal cavity (group II, 100 mL total). Both were compared with the administration of 50 mL of dye through a catheter placed in the dorsal nasal meatus via each nostril (group III). The heads in group III had significantly ( P <.05) better dye distribution to all cavities than group IA and better distribution to the rostral frontal sinus than group II. Groups IV to VI were designed to show the pattern of distribution of dye to the contralateral nasal cavity and frontal sinuses. In all groups, dye injected into the lateral frontal sinus did not cross into the ipsilateral rostral frontal sinus or vice versa unless the transverse septum dividing the compartments had been penetrated during trephination.     

Comminuted First Phalanx Fractures in 30 Horses: Surgical vs. Nonsurgical Treatments

Comminuted first phalanx fractures were diagnosed in 30 horses. One leg was involved in each horse. Five horses were presented with open fractures. Nine horses had a portion of intact cortex (strut) extending from the proximal to distal joint. Ten horses were euthanized, including one with an open fracture, without treatment. The remaining 20 horses were treated by open reduction with a neutralization plate (8 horses, including one with an open fracture), open reduction with lag screw fixation (3 horses), lag screw fixation through stab incisions (2 horses), external coaptation with a cast (3 horses), and external skeletal fixation using a weight supporting shoe (4 horses, including 3 with open fractures).
Thirteen horses were euthanized following treatment because of persistent infection (9), chronic lameness (2), and third metacarpal bone fractures (2). Seven horses survived longer than 1 year after treatment. Six were lame and used as breeding animals, and one horse went on to race successfully. All four horses with open fractures that were treated were subsequently euthanized.
Significantly more horses with an intact strut of bone survived after treatment (4 of 7 [57%]) when compared to horses without an intact strut of bone that were treated (3 of 13 [23%]) (p < 0.05).
Invasive surgical approaches used for the repair of comminuted first phalanx fractures in this study were associated with an unacceptable infection rate (55%). Techniques involving less trauma to the compromised soft tissue around the fracture should afford a better chance for a successful outcome.     

Formation of Chiral Interdigitated Multilayers at the Air-Liquid Interface Through Acid-Base Interactions

Thin interdigitated films composed of a long-chain, water-insoluble chiral acid (p-pentadecylmandelic acid of absolute configuration R) and a water-soluble chiral base (phenylethylamine, R') were constructed at the air-solution interface. The (R, R') structure was characterized to near-atomic resolution by grazing-incidence x-ray diffraction (GIXD). The two diastereomeric systems, (R, R') and (R, S'), demonstrate similar surface pressure-molecular area isotherms, but their structures are completely different on the molecular level, as monitored by GIXD. Complementary data on these two architectures were provided by atomic force microscopy.     

Pharmacokinetic Disposition of Cefazolin in Serum and Tissue during Canine Total Hip Replacement

Intraoperative cefazolin concentrations were measured in serum, joint capsule, cancellous bone of the acetabulum, and proximal cancellous bone of the femur in 15 dogs undergoing total hip replacement. Cefazolin (22 mg/kg intravenously [IV]) was administered every hour for three doses. The mean peak serum concentrations (+/- SEM) were 387.79 +/- 27.56 micrograms/mL, 521.71 +/- 28.00 micrograms/mL, and 542.20 +/- 30.91 micrograms/mL, respectively. Mean serum concentrations just before administration of doses 2 and 3 were 51.77 +/- 2.39 micrograms/mL, and 64.84 +/- 3.46 micrograms/mL, respectively. The mean cefazolin concentrations in the joint capsule, cancellous bone of the acetabulum, and cancellous bone of the femur were 34.71 +/- 2.50 micrograms/g, 28.70 +/- 7.40 micrograms/g, and 36.20 +/- 3.80 micrograms/g, respectively. The minimum inhibitory concentration of cefazolin for 90% of the common contaminants (MIC90) in this clinic is less than or equal to 2 micrograms/mL or per gram of tissue. Serum concentrations never fell below 15 times the MIC90 (lowest trough, 35.93 micrograms/mL), and the lowest tissue concentration (6.57 micrograms/mL in cancellous bone from the acetabulum) was still more than 3 times the MIC90. The mean tissue concentration was 15 times the MIC90.