Malignant lymphoma with B-lymphocyte characteristics in dogs.

Cell surface membrane characteristics of B and T lymphocytes were demonstrated on cells from canine malignant lymphoma, and the results were compared with cytologic classification. Lymphoma in 4 of 5 dogs was found to have one or more characteristics of B lymphocytes. Correlation between the cytologic classification and the presence of B- and T-lymphocyte characteristics was not apparent.     

Uveitis associated with poliosis and vitiligo in six dogs

Idiopathic panuveitis with retinal detachment was associated with facial poliosis, vitiligo, and alopecia in 6 dogs; 4 were adult males. Dermatohistologic examination of affected facial sites from all dogs revealed a lichenoid dermatitis and unusual histiocytic cells. Intensive topical and systemic corticosteroid and topical mydriatic/cycloplegic therapy was successful in controlling uveitis in all dogs for variable periods. Three dogs, monitored for 12, 30, and 46 months, retained useful vision despite infrequent recurrence of uveitis. One dog was lost for subsequent examination. Two dogs were euthanatized and necropsied. Ocular histologic examination of these dogs revealed extensive granulomatous iridocyclitis and choroiditis, with retinal detachment and lenticular degeneration.     

Decreased tear production associated with general anesthesia in the horse

Schirmer I tear tests were conducted on 14 horses. The test was performed before and after IV administration of xylazine hydrochloride, during maintenance anesthesia with halothane in oxygen, and 3 hours after discontinuation of anesthesia. Xylazine hydrochloride did not decrease tear production from the mean base-line value of 23.94 +/- 5.23 mm/min after its IV administration. Tear production was decreased to mean values of 15.57 +/- 4.29 mm/min at 30 minutes and 13.84 +/- 4.25 mm/min at 60 minutes during the maintenance of halothane anesthesia. Three hours after anesthesia was discontinued, tear production returned to a mean value of 22.58 +/- 4.12 mm/min.     

CANINE CHEMONUCLEOLYSIS

Lumbar and cervical chemonucleolysis was evaluated on 16 clinically normal adult Beagle dogs in two age groups, using chymopapain at dose rates of 200 and 500 units (U). Lumbar discs injections in four discs were made transcutaneously under fluoroscopic guidance, and cervical disc injections in four discs were made after surgical exposure. Postinjection radiographs revealed a progressive narrowing of the disc spaces, first noted 24 hours after injection. Gross examination of the discs at 1-, 2-, 4-, and 8-day intervals showed a time-dependent change, with no detectable difference between the two doses and age groups. The overall rate of successful chemonucleolysis was 82.4% in the cervical discs and 78% in the lumbar discs. Clinically, the dogs showed minimal evidence of pain and no detectable postural abnormality following chemonucleolysis.     

MAGNETIC RESONANCE IMAGING AND COMPUTED TOMOGRAPHY CHARACTERISTICS OF INTRACRANIAL INTRA-ARACHNOID CYSTS IN 6 DOGS

Magnetic resonance imaging (MRI) and computed tomographic imaging (CT) characteristics of intracranial intra-arachnoid cysts in six dogs are described.Of the six dogs, three were less than one year of age and 4 were males. Five of the six dogs weighed less than 11 kg. Five cysts were located in the quadrigeminal cistern.On CT images, the intracranial intra-arachnoid cysts had sharply defined margins, contained fluid isodense to CSf and did not enhance following IV administration of contrast. On MRI images, the intracranial intra-arachnoid cysts were extra-axial, contained fluid isointense with CSF and did not enhance following IV contrast. While spinal arachnoid cysts of dogs have been reported in the literature, other than the six dogs contained in this report, intracranial intra-arachnoid cysts have not to our knowledge been described in animals. These six dogs have a similar age, sex, arachnoid cysts.     

Mouse scrapie and polyadenylated RNA metabolism in L cells

It has previously been reported that infection of mice with the scrapie agent alters polyadenylated RNA (poly (A) RNA) metabolism. In particular, it was claimed that incubation of L cells with extracts from scrapie-infected mice changed the level of poly (A) RNA in the L cells. We have attempted to repeat this work, using the original techniques, but have been unable to confirm the published findings. Furthermore our work suggests that the techniques used would not have yielded purified poly (A) RNA, and analysis of the data from the previous publications supports this view.     

Metabolism of methylated analogs of aldrin and dieldrin by liver preparations from male and female rat

Analogs of aldrin and dieldrin have been synthesized, the molecules of which lack a methylene bridge but have two methyl groups attached to olefinic or oxirane ring carbon atoms. Their metabolism was studied using NADPH-supplemented 12,000g × 30-min supernate of livers from Wistar and CD strains of rats. The dimethylated olefin was not metabolized to its epoxide but was converted by supernate of liver from rats of both sexes to a labile hydroxylated metabolite. Exogenous NADPH increased the rate at which the olefin was metabolized, but concentrations of NADPH which increased the yield of the labile metabolite when added to female rat liver preparations decreased the yield when added to those from the male. This metabolite had a mass spectrum which was consistent with it being a hydroxymethyl derivative. The dimethylated epoxide was metabolized more slowly than the olefin, and a notable sex difference in the route of metabolism was evident. With supernate from livers of female rats the only metabolite detected by gas-liquid chromatography had a mass spectrum consistent with it being a ring-hydroxylated epoxide. Male rat liver supernate formed small quantities of the same compound, but the major metabolite had a mass spectrum indicative of a hydroxymethyl epoxide. No hydrolysis of the oxirane ring of the epoxide has been detected. The relevance of these results to the planned synthesis of cyclodienes of optimal biodegradability is mentioned.     

Stressor effects of handling on the immature fowl.

Chicks were handled for 5 min twice daily for five consecutive days per week over a three-week period. The control birds were not handled once they had been allotted to their brooders. The growth rate of the treated birds was significantly decreased. There was no adrenal hypertrophy; the concentration, but not the content, of adrenal cholesterol was significantly increased. Plasma glucose, FFA and cholesterol concentrations were similar in the groups at the end of the experiment. The lipolytic response of the handled birds to a further stimulus of handling was significantly greater than that of unhandled birds experiencing novel handling stimulus. There was also a significant decrease in the concentration of corticosterone in the plasma of the handled birds but not in the unhandled group. There was thus no evidence of habituation.     

Scintigraphic evaluation of metacarpophalangeal and metatarsophalangeal joints in clinically sound horses.

The purpose of this study was to describe the pattern of radiopharmaceutical uptake in the metacarpophalangeal (MCP) and metatarsophalangeal (MTP) (fetlock) joints in clinically sound horses. Scintigraphic images from 29 clinically normal horses were evaluated. All the images were assessed subjectively. The lateral views were assessed quantitatively using vertical line profiles through the center of the joint, and mean ratios of radiopharmaceutical uptake were calculated from regions of interest around the third metacarpal or metatarsal bones, and the proximal phalanx and proximal sesamoid bones. From the vertical line profiles, in the majority of forelimbs (65%) the peak activity of radiopharmaceutical distribution was at the proximal region of the proximal phalanx, with a significantly lower activity within the condyles of the third metacarpal bone. However, in 84% of hindlimbs there was a broader profile peak incorporating the condyles of the third metatarsal bone and the proximal aspect of the proximal phalanx, indicating a more generalized even uptake of radiopharmaceutical across the MTP joint. When the regions of interest were compared between front and hindlimbs, there was no significant difference between proximal phalanx and proximal sesamoid bones, but the distal condyles of the third metacarpal bone of the forelimb had significantly lower radiopharmaceutical activity than hindlimbs (P < 0.04). In lateral images, the mean forelimb ratios tended to be higher in the left MCP joint compared with the right (P = 0.069). In hindlimbs, the mean ratios tended to be higher in the right MTP joint than the left (P = 0.052). There was no significant effect of age.