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J F Randolph

Publications and source records attributed to J F Randolph.

82 records · Page 5Linked to original sources

Fibrodysplasia ossificans progressiva in the cat. A case report.

Clinical, radiographic, electromyographic, and pathologic findings in a cat with fibrodysplasia ossificans progressiva are described. The features of five previously reported cases of this feline disorder are also presented. This disorder affects young adult to middle-aged cats of both sexes. Characteristic clinical features include progressive stiffness of gait, with enlargement of proximal limb musculature. Radiography reveals multiple mineralized densities within the affected musculature. The clinical course is rapid, with development of severe disability within 2 weeks to several months. Electromyographic and pathologic findings suggest that this is a disorder of connective tissue, affecting primarily the epimysium, tendons, and fasciae, and results in marked proliferation of fibrovascular connective tissue, with associated chondroid and osseous metaplasia.

Animals↗

Glomerular filtration rate and renal volume in dogs with congenital portosystemic vascular anomalies before and after surgical ligation.

Glomerular filtration rate (GFR) and renal volume were evaluated in dogs with confirmed portosystemic vascular anomalies (PSVA) before and after surgical ligation of their PSVA. Pre- and postligation CBC, serum biochemistry, urinalysis, abdominal ultrasonography with measurement of renal volume, and per rectal scintigraphy were performed to document resolution of abnormalities consistent with portosystemic shunting. GFR was estimated by plasma 99mTc-diethylenetriaminepentaacetic acid (99mTc-DTPA) clearance before (n = 21) and after (n = 12) surgical correction of PSVA. Preligation 99mTc-DTPA GFR was increased (median, 5.64 mL/minute/kg; range, 3.53-8.49 mL/minute/kg; reference range, 2.83-4.47 mL/minute/kg) in 81% (17/21) of dogs. Postligation 99mTc-DTPA GFR decreased in all 12 evaluated dogs (median change = -42%; P < .001). Preligation renal volume was above the reference range for the left and right kidneys in 71% (10/14) and 69% (11/16) of dogs evaluated, respectively. Right renal volume decreased significantly (n = 5; median change, -45%; P = .03) after surgical ligation of PSVA. These findings document increased GFR and renal volume in dogs with PSVA, which may explain in part the low blood urea nitrogen and serum creatinine concentrations encountered in these dogs. Knowledge of changes in GFR associated with PSVA ligation may prove helpful in the anesthetic, drug, and dietary management of affected dogs.

Animals↗

Prothrombin, activated partial thromboplastin, and proteins induced by vitamin K absence or antagonists clotting times in 20 hyperthyroid cats before and after methimazole treatment.

The effect of daily doses of 5-15 mg of methimazole on the platelet count, prothrombin time (PT), activated partial thromboplastin time (APTT), and proteins induced by vitamin K absence or antagonists (PIVKA) clotting time in 20 hyperthyroid cats was determined. No significant (P > .05) difference was found in median platelet count. PT, APTT, or PIVKA clotting time before treatment compared to median values at 2-6 weeks or > or =7-12 weeks of methimazole treatment. No cat had a prolonged APTT at any time. At 2-6 weeks of methimazole treatment, 1 cat each developed thrombocytopenia or prolonged PIVKA clotting time despite initially normal values. Three cats had abnormal coagulation tests (prolonged PT [n = 1] and PIVKA clotting time [n = 3]) before treatment that fluctuated during treatment. Excluding the 3 cats that had abnormal PIVKA clotting time before treatment, prolonged PIVKA clotting time developed in 6% (1/17; 95% confidence interval, 0-28%) cats treated with methimazole for 2-6 weeks. Seemingly. doses of methimazole commonly used to treat hyperthyroidism in cats do not cause alteration in PT and APTT, and only rarely prolong PIVKA clotting time. Nevertheless, abnormal PIVKA clotting time may explain bleeding tendencies unassociated with thrombocytopenia in methimazole-treated hyperthyroid cats.

Animals↗

Proteins invoked by vitamin K absence and clotting times in clinically ill cats.

The clinical utility of the Thrombotest, a method for determining the prothrombin time that is uniquely sensitive to the presence of proteins invoked by vitamin K absence (PIVKA), was prospectively evaluated and compared to routine coagulation tests in cats with clinically suspected bleeding tendencies. Abnormal PIVKA clotting values were determined by comparison to results of a concurrently evaluated pooled feline plasma sample and by use of an absolute cutoff value of 25.2 seconds. To be recognized as abnormal, PIVKA clotting values had to be >20% of the pooled feline plasma PIVKA clotting time (the "20% rule") or > or =25.2 seconds (mean + 2 standard deviations of 150 different pooled feline plasma samples). Among the disorders in the population examined were 74 cats with liver disease and 19 cats with severe inflammatory bowel disease. Overall, a prolonged PIVKA clotting time based on the 25.2-second cutoff was found in 39.3% of cats, and based on the 20% rule in 40.7% of cats. An abnormal prothrombin time (PT) developed in 5.8% of cats, an abnormal APTT in 14% of cats, subnormal fibrinogen in 8.8% of cats, and thrombocytopenia in 3.3% of cats. Bleeding tendencies were confirmed in 22 cats, of which abnormal PIVKA clotting times were recognized in 95.5%, abnormal PT in 21%, abnormal activated partial thromboplastin time in 25%, hypofibrinogenemia in 16.7%, and thrombocytopenia in 4.5%. Response to treatment with vitamin K was demonstrated in 21 of 24 cats with an abnormal PIVKA clotting time. In these cats, an abnormal PIVKA clotting time normalized within 3 to 5 days of parenteral vitamin K administration. Cats responding to vitamin K administration had hepatic lipidosis (n = 7), severe inflammatory bowel disease (n = 4), severe inflammatory bowel disease associated with cholangiohepatitis (n = 5), and miscellaneous disorders (n = 5). Using either endpoint, the PIVKA clotting time is more sensitive for the detection of cats with coagulopathies than routinely used coagulation assessments in our hospital. Our findings confirm that cats with hepatic lipidosis, severe cholangiohepatitis, and severe inflammatory bowel disease develop coagulopathies responsive to vitamin K administration.

Animals↗

Idiopathic hypercalcemia in cats.

Unexplained hypercalcemia has been increasingly recognized in cats since 1990. In some instances, hypercalcemia has been associated with calcium oxalate urolithiasis, and some affected cats have been fed acidifying diets. We studied the laboratory findings, clinical course, and treatment of 20 cats with idiopathic hypercalcemia. Eight (40%) of the cats were longhaired and all 14 cats for which adequate dietary history was available had been fed acidifying diets. Clinical signs included vomiting (6 cats), weight loss (4 cats), dysuria (4 cats), anorexia (3 cats), and inappropriate urinations (3 cats). Hypercalcemia was mild to moderate in severity. and serum parathyroid hormone concentrations were normal or low. Serum concentrations of phosphorus, parathyroid hormone-related peptide, 25-hydroxycholecalciferol, and calcitriol were within the reference range in most cats. Diseases commonly associated with hypercalcemia (eg, neoplasia, primary hyperparathyroidism) were not identified despite thorough medical evaluations and long-term clinical follow-up. Azotemia either did not develop (10 cats) or developed after the onset of hypercalcemia (3 cats), suggesting that renal failure was not the cause of hypercalcemia in affected cats. Seven of 20 cats (35%) had urolithiasis, and in 2 cats uroliths were composed of calcium oxalate. Subtotal parathyroidectomy in 2 cats and dietary modification in 11 cats did not result in resolution of hypercalcemia. Treatment with prednisone resulted in complete resolution of hypercalcemia in 4 cats.

Animal Feed↗

The effects of S-adenosylmethionine on clinical pathology and redox potential in the red blood cell, liver, and bile of clinically normal cats.

S-adenosylmethionine (SAMe), an important hepatic metabolite and glutathione (GSH) donor, has been studied mechanistically in vitro, in humans with clinical liver disease, and in experimental animal models of liver disease. Collective findings encourage its therapeutic use in necroinflammatory and cholestatic liver disorders. A chronic longitudinal study (pre- and posttreatment parameters compared) was undertaken with 15 clinically healthy cats given a stable 1,4-butanedisulfonate (S'S isomer) SAMe salt (enteric coated tablets providing 180 mg SAMe), dosage 48 mg/kg PO q24h, on an empty stomach for 113 days. Routine physical and clinicopathologic assessments, red blood cell (RBC) osmotic fragility, liver function and histology, hepatic concentrations of reduced GSH (RGSH) and its oxidized disulfide form (GSSG), protein, glycogen, and deoxyribonucleic acid, GSH concentrations in RBCs, total bile acids in serum and bile, oxidative membrane products (TBARS) in RBCs and liver, and plasma SAMe concentrations were evaluated. SAMe administered PO significantly increased plasma SAMe concentrations, and peak concentrations usually occurred 2-4 hours after dosing. Chronic SAMe administration did not change peak or cumulative plasma SAMe concentrations and did not [corrected] cause overt signs of toxicity. A positive influence on RBC and hepatic redox status (RBC TBARS reduced 21.1% [P < .002], liver GSH increased 35% [P < .002], liver RGSH: GSSG ratio increased 69% [P < .03]) and improved RBC resilience to osmotic challenge (P < .03) were observed. Results prove that this SAMe PO product is enterically available and suggest that it imparts biologic effects that might be useful for attenuating systemic or hepatic oxidant challenge.

Animals↗

Primary hyperaldosteronism in two cats.

A condition of primary hyperaldosteronism resulting from an adrenal tumor in two cats is presented and was characterized by hypertension, hypokalemia, inappropriate kaliuresis, low normal plasma renin activity, and markedly increased serum aldosterone concentration. One of the two cats underwent a laparotomy, and in this case hypertension and hypokalemia resolved following the removal of an adrenal tumor.

Adrenal Gland Neoplasms↗

Changes in bone density with lactation.

OBJECTIVE: To test the a priori hypotheses that significant bone loss occurs in lactation of greater than 5 months' duration and that bone mass returns to baseline levels when breast-feeding ceases. DESIGN: Prospective cohort study design of 12 months' duration. SETTING: General community setting with recruitment occurring at birthing education classes. PARTICIPANTS: Volunteer sample of 98 healthy women of white (n = 95) and Asian (n = 3) origin, aged 20 to 40 years, and 0 to 1 parity prior to parturition, grouped according to lactation duration: 0 through 1, 2 through 5, and 6 or more months. MAIN OUTCOME MEASURES: Bone mineral density (BMD) of the proximal femur was measured by dual-energy x-ray densitometry at 2 weeks (baseline), 2 months, 4 months, 6 months, and 12 months following parturition, and BMD of the lumbar spine was measured at baseline, 6 months, and 12 months after parturition. RESULTS: Women with lactation duration of 6 months or longer had mean BMD losses of 5.1% and 4.8% at the lumbar spine and femoral neck, respectively, comparing baseline values with those at 6 months post partum. Women who breast-fed 0 through 1 month lost no BMD at either bone site. Bone loss in women who breast-fed 6 months or longer was not explained by differences in age, diet, body size, or physical activity. Among women who breast-fed 6 months or longer, there was evidence of return to baseline levels of the lumbar spine at 12 months after parturition. The BMD of the lumbar spine of those women who continued to breast-feed more than 9 months had increased but was still significantly lower than baseline. CONCLUSION: Extended lactation (> or = 70% of energy intake is provided for > or = 6 months) is associated with bone loss; however, there is evidence of return to baseline BMD measurement at 12 months after parturition.

Absorptiometry, Photon↗