Biomedical subjects

E W Howerth

Publications and source records attributed to E W Howerth.

59 records · Page 4Linked to original sources

PubMed1981

Pulmonary artery thrombosis in three dogs with hyperadrenocorticism.

Varying degrees of respiratory distress developed in 3 dogs in which hyperadrenocorticism was diagnosed. The respiratory distress was attributed to pulmonary artery thrombosis. Radiography revealed pleural effusion, increased diameter and blunting of the pulmonary arteries, lack of perfusion of the obstructed pulmonary vasculature, and overperfusion of the unobstructed pulmonary vasculature. Thrombosis was confirmed by nonselective angiocardiography in each case. In 1 case, selective angiocardiography showed marked reduction of the transit time of contrast medium from the right atrium to the aorta. Hypertension proximal to the site of thrombosis was confirmed in 2 cases by showing increases in the right ventricular systolic pressures (80 mm of Hg in one case and 54 mm of Hg in the other case). In 3 cases, there was moderate hypoxemia with hypocapnia, suggesting a ventilation-perfusion mismatch. Clinical findings other than respiratory distress included hepatomegaly, ventral edema, orthopnea, and a jugular pulse. Pulmonary artery thrombosis, as it occurred in these 3 cases, was compared with the disease in man. It was concluded that pulmonary artery thrombosis should be suspected in cases of intractable dyspnea, right-sided heart failure of unexplained origin, and acute unexplainable death.

Adrenocortical Hyperfunction↗

PubMed1981

Bovine cryptosporidiosis.

Intestinal cryptosporidiosis was detected at necropsy in a 2-week-old calf that had diarrhoea. Cryptosporidial organisms were embedded in the microvillous border of the epithelium of the distal small intestine. The most significant histological change was a mild enteritis characterized by decreased villus length and hypercellularity of the lamina propria.

Animals↗

PubMedDate not supplied

Copper deficient rat heart can compensate for doxorubicin-induced oxidant stress.

The hypothesis that copper (Cu) alters drug metabolizing enzymes and functions as an antioxidant nutrient in doxorubicin cardiotoxicity was tested. Male Sprague-Dawley rats were fed Cu adequate (+Cu; 5 mg Cu/kg of diet), marginally Cu deficient (MCu; 1.2 mg Cu/kg of diet), or severely Cu deficient (-Cu; 0.5 mg Cu/kg of diet) diets for 6 wk. Doxorubicin (1, 2, or 4 mg/kg body wt) or saline were administered intraperitoneally 1 time/wk for 4 wk. Compared to control hearts, Cu,Zn superoxide dismutase activity was decreased by 9% in MCu rats and by 21-40% in -Cu rats. Glutathione peroxidase activity was elevated 5-15% in -Cu rats. Doxorubicin administration increased heart Cu,Zn superoxide dismutase activity in +Cu and -Cu rats 18 h after the last of 4 injections, but not 18 h after 1 injection. There was no synergism between doxorubicin and Cu deficiency on lipid peroxidation, plasma creatine phosphokinase, cardiac hypertrophy, electrocardiographic abnormalities, or morphological changes. Heart glutathione S-transferase activity was decreased by Cu deficiency, and like Cu,Zn superoxide dismutase activity, returned to normal in -Cu rats given doxorubicin. Thus, the Cu deficient rat heart may be able to compensate for doxorubicin-induced oxidant stress by increasing the activity of Cu,Zn superoxide dismutase and glutathione S-transferase.

Animals↗

PubMedDate not supplied

Fatal toxoplasmosis in a red lory (Eos bornea).

Toxoplasmosis was diagnosed in a 3-week-old red lory (Eos bornea). Grossly, there was hepatomegaly and pulmonary consolidation. The salient microscopic lesions were multifocal necrotizing mycocarditis, interstitial pneumonia with multifocal necrosis and vasculitis, and multifocal necrotizing hepatitis with periacinar hepatocellular necrosis. Toxoplasma gondii-like organisms were observed in lung, heart, and liver by light and electron microscopy. The organisms in tissues stained with anti-T. gondii serum using an immunohistochemical method.

Animals↗

PubMedDate not supplied

Neoplasia in free-flying ruffed grouse (Bonasa umbellus).

Neoplasms were identified in 3 of 13 free-flying ruffed grouse submitted to the Southeastern Cooperative Wildlife Disease Study during a 10-year period. These neoplasms were a lipoma, a fibroma, and a renal carcinoma metastatic to the liver.

Animals↗