Evaluation of Histological, Immunohistochemical, Clinical and Genetic Prognostic Factors Associated with the Response of Canine Mast Cell Tumours to Glucocorticotherapy.

Mast cell tumours (MCTs) are one of the most frequent neoplasms in dogs. Glucocorticoids (GCs) are widely used in the management of this disease, although no guidelines for their use have been established. The aim of this study was to evaluate the correlation of MCT prognostic factors with measurable response to GCs. This retrospective study included 60 dogs treated with prednisone or prednisolone prior to surgical biopsy of MCT. Incisional or excisional biopsy was performed 7-14 days after initiation of GC therapy. Histopathology, immunohistochemical labelling for Ki67 and KITr, and polymerase chain reaction for the c-KIT gene were performed. Partial response occurred in 63.3% of cases (38/60), while 36.7% (22/60) did not respond. A response to GCs was correlated with lower stage of the disease, low histological grade, lower pattern of KITr expression and Ki67 score. Response to GCs was positively correlated with well-established favourable prognostic factors.

Further observations on the interaction between sugar cane and Gluconacetobacter diazotrophicus under laboratory and greenhouse conditions.

Sugar cane (Saccharum spp.) variety SP 70-1143 was inoculated with Gluconacetobacter diazotrophicus strain PAL5 (ATCC 49037) in two experiments. In experiment 1 the bacteria were inoculated into a modified, low sucrose MS medium within which micropropagated plantlets were rooted. After 10 d there was extensive anatomical evidence of endophytic colonization by G. diazotrophicus, particularly in lower stems, where high numbers of bacteria were visible within some of the xylem vessels. The identity of the bacteria was confirmed by immunogold labelling with an antibody raised against G. diazotrophicus. On the lower stems there were breaks caused by the separation of the plantlets into individuals, and at these 'wounds' bacteria were seen colonizing the xylem and intercellular spaces. Bacteria were also occasionally seen entering leaves via damaged stomata, and subsequently colonizing sub-stomatal cavities and intercellular spaces. A localized host defence response in the form of fibrillar material surrounding the bacteria was associated with both the stem and leaf invasion. In experiment 2, stems of 5-week-old greenhouse-grown plants were inoculated by injection with a suspension of G. diazotrophicus containing 10(8) bacteria ml(-1). No hypersensitive response (HR) was observed, and no symptoms were visible on the leaves and stems for the duration of the experiment (7 d). Close to the point of inoculation, G. diazotrophicus cells were observed within the protoxylem and the xylem parenchyma, where they were surrounded by fibrillar material that stained light-green with toluidine blue. In leaf samples taken up to 4 cm from the inoculation points, G. diazotrophicus cells were mainly found within the metaxylem, where they were surrounded by a light green-staining material. The bacteria were growing in relatively low numbers adjacent to the xylem cell walls, and they were separated from the host-derived material by electron-transparent 'haloes' that contained material that reacted with the G. diazotrophicus antibody.

Osteotomy of the radius and ulna for the Madelung deformity.

The Madelung deformity can result in pain and decreased function of the wrist and hand. None of the surgical techniques available has been shown consistently to improve grip strength, range of movement or relieve pain. In this prospective study we have treated 18 patients with the Madelung deformity (25 wrists) by wedge subtraction osteotomy of the radius and shortening of the ulna. Our results show statistically significant improvement in grip strength and range of movement of the wrist and forearm. Pain improved in 80% of the patients and 88% were satisfied with the appearance. One patient had a wound infection and another developed reflex sympathetic dystrophy. Two had some recurrence due to continued growth of the ulna and it is recommended that the procedure be delayed until skeletal maturity, or else combined with epiphysiodesis of the ulna.

Internal fixation of scaphoid injuries using the Herbert screw through a dorsal approach.

This prospective study reports on the use of the Herbert screw for fixation of fractures and nonunions of the scaphoid through a dorsal approach. In cases of delayed union and nonunion, screw fixation was combined with bone grafting. Twenty-five patients were treated in this manner, and union rates of 100% for acute fractures and 87% for delayed union and nonunion were achieved. We believe that the dorsal approach provides ready access to the scaphoid, enabling placement of the screw in the best possible position to provide fracture fixation.