Coliform myositis in a calf

Coliform myositis was diagnosed in a young calf with signs of pain, swelling, and edema of the right hind limb. Diagnostic methods included bacteriologic culture and antimicrobial susceptibility testing. The organism isolated was a gas-producing Escherichia coli. The infection responded to administration of trimethoprim/sulfadiazine, to which the organism was susceptible in vitro.     

EXCRETORY UROGRAPHY AND ULTRASONOGRAPHY IN THE DIAGNOSIS OF BILATERAL ECTOPIC URETERS IN A FOAL

A 7-week-old Appaloosa filly was admitted for persistent urinary incontinence since birth. Vaginal speculum examination revealed urine flowing from an opening in the right vaginal wall. Cystoscopy demonstrated that the ureters did not terminate at the bladder. The endoscope passed easily from the vagina directly into a dilated right ureter. An excretory urogram confirmed the vaginal termination of at least one ureter, based upon extensive filling of the vagina with contrast media in the absence of bladder filling. Bilateral hydroureter and dilated renal pelves were demonstrated both by excretory urography and by ultrasonography. Euthanasia was requested by the owner in lieu of attempted surgical correction. At necropsy, it was confirmed that the right ureter entered the vagina and the left ureter terminated at the urethra. The diagnosis of bilateral ectopic ureter in this foal was suggested by the history and clinical signs, supported by endoscopy and ultrasonography, and confirmed by excretory urography and necropsy. This case establishes the value of diagnostic imaging techniques in the antemortem diagnosis of ectopic ureter.     

Proximity of chromosomal loci that participate in radiation-induced rearrangements in human cells

Rearrangements involving the RET gene are common in radiation-associated papillary thyroid cancer (PTC). The RET/PTC1 type of rearrangement is an inversion of chromosome 10 mediated by illegitimate recombination between the RET and the H4 genes, which are 30 megabases apart. Here we ask whether despite the great linear distance between them, RET and H4 recombination might be promoted by their proximity in the nucleus. We used two-color fluorescence in situ hybridization and three-dimensional microscopy to map the positions of the RET and H4 loci within interphase nuclei. At least one pair of RET and H4 was juxtaposed in 35% of normal human thyroid cells and in 21% of peripheral blood lymphocytes, but only in 6% of normal mammary epithelial cells. Spatial contiguity of RET and H4 may provide a structural basis for generation of RET/PTC1 rearrangement by allowing a single radiation track to produce a double-strand break in each gene at the same site in the nucleus.     

Closure of the iliac crest ossification center in dogs: 750 cases (1980-1987).

Radiographs of 750 dogs were examined to determine whether the iliac crest ossification center was open or closed. The center was closed in most dogs by 2 years of age. Eighteen percent of dogs greater than or equal to 10 years old had open iliac crest ossification center; 10% of dogs greater than or equal to 14 years old had open iliac crest ossification center. Closure of the iliac crest ossification center is extremely variable and, in many dogs, occurs at later age than has been previously reported.