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Biomedical subjects

C F Simpson

Publications and source records attributed to C F Simpson.

At least 55 records · Page 3Linked to original sources
PubMed1981

Congealed amniotic fluid in the alveoli of lungs of aborted foals.

The alveoli of the lungs of 2 aborted foals contained elongated, dense bodies when examined histologically and by transmission and scanning electron microscopy. By light microscopy, the bodies (10 to 40 micrometers in size) stained intensely with the Gram stain, and up to 10 were present within an alveolus. Electron microscopy determined that such bodies were not cellular in origin but appeared to be a congealed fluid product composed of layers of fibrillar-like material. From the human literature, it was concluded that these intraalveolar bodies were probably congealed amniotic fluid.

Abortion, Veterinary↗
PubMed1981

Electron microscopy of a spiral-shaped bacterium in the blood and bone marrow of a rhinoceros iguana.

Spiral shaped bacteria present in blood smears and bone marrow of a sick rhinoceros iguana were examined by light and electron microscopy. The organisms averaged 10 micron in length and had at least three spiral turns. The cell contained nuclear areas, vacuoles and ribosomes, except at the poles where there was a virtual absence of organelles. The bacterium was found by a cell membrane, cell wall and enveloping sheath. "Blebs" were present with regularity on the cell surface. About 14 flagella were present at each pole, and at these sites there was a specialized thickening of the cell membrane. Organisms were present within a phagocytic vacuole of macrophages in the blood and bone marrow, and often these engulfed organisms were degenerated. The taxonomic position of the bacterium is unknown.

Animals↗
PubMed1980

Paramyxo-like virus infection in a rock rattlesnake.

A rock rattlesnake (Crotalus lepidus) with a history of progressive central nervous disease was submitted for necropsy. The histopathologic findings included evidence of interstitial pneumonia, multifocal areas of gliosis in the brain, and ballooning degeneration and demyelination of brainstem and upper spinal cord axons. By electron microscopy, brainstem tissue was found to contain numerous virus particles in the extracellular spaces. A paramyxo-like virus, isolated in viper heart cells from lung tissue, was observed by electron microscopy to be similar in size and shape to the particles seen in nerve tissue.

Animals↗
PubMed1980

Evidence for Sarcocystis as the etiologic agent of equine protozoal myeloencephalitis.

Equine protozoal myeloencephalitis (EPM) was diagnosed in 10 horses. By electron microscopy, schizonts were found in intact host cells of the spinal cords or, more frequently, free in the extracellular spaces. Developmental stages of schizonts differed morphologically, and the late stage of schizogony was characterized by endopolygeny. These findings permitted tentative identification of the protozoon as a Sarcocystis sp. Free merozoites were present in the extracellular spaces or in cells of the spinal cord. Pericytes of capillaries were most frequently parasitized by merozoites were present in the extracellular spaces or in cells of te spinal cord. Pericytes of capillaries were most frequently parasitized by merozoites, but the cytoplasm of neurons, macrophages, intravascular and tissue neutrophils, and axons of myelinated nerve fibers also contained these organisms. The presence of parasites in the cytoplasm of tissue and circulating neutrophils suggest that this putative Sarcocystis sp. may have a hematogenous phase of infection.

Animals↗
PubMed1980

Experimental infection of sheep with Naegleria fowleri of human origin.

A strain of Naegleria fowleri, isolated from a child who died of primary amebic meningoencephalitis in Florida, was instilled in the nostrils of a sheep to determine whether livestock are susceptible to infection with free-living amebae. The animal died 7 days later from amebic infection of the central nervous system. N. fowleri were recovered from the brain and spinal cord of the animal. A control, saline-instilled sheep that had been pair-caged with the infected animal remained healthy.

Amebiasis↗
PubMed1980

Crystalline inclusions in erythrocytes parasitized with Babesia equi following treatment of ponies with imidocarb.

Four splenectomized Welsh ponies were infected with Babesia equi. Two ponies were treated with imidocarb dipropionate, and two were not treated. By light microscopic examination, 1% to 2% of the parasitized erythrocytes of treated ponies contained crystalline inclusions. The crystals were rectangular, diamond, or burr shaped. They occupied most of the erythrocytic cytoplasm, and, as a result, the remainder of the pale staining cytoplasm was inconspicuous in Wright-Giemsa-stained blood smears. The size and shape of intraerythrocytic inclusions varied when examined by electron microscopy, but in most instances they were either adhered to or were located close to the parasite. The sides of crystals were either smooth or serrated, and corners were either sharp or notched. Fractures or faults were common in large crystals. Parasitized erythrocytes of nontreated ponies and nonparasitized erythrocytes of treated ponies did not contain crystals. Four hemoglobulin types were identified in five noninfected, nontreated Welsh ponies from the same herd.

Animals↗
PubMed1980

Ultrastructure of Babesia equi in ponies treated with imidocarb.

Four splenectomized ponies were infected with Babesia equi. Two ponies were not treated, and two were treated with 5 mg of imidocarb/kg of body weight when 20% of their erythrocytes were parasitized. The nucleus of the parasite in erythrocytes from blood smears of nontreated ponies was roundish, deep red-staining, and usually composed two-thirds of the organism. The parasite in erythrocytes from blood smears of treated ponies was swollen and vacuolated except for an area just beneath the plasma membrane where the compressed nucleus was marginated, elongated, and clumpy. Parasites in erythrocytes from nontreated and treated ponies were examined by electron microscopy. Babesia equi in erythrocytes of nontreated ponies contained food vacuoles, a prominent nucleus, smooth and rough endoplasmic reticulums, and ribosomes. There were four stages of degeneration of B equi in erythrocytes of ponies treated with imidocarb. The first stage was dilatation of the nuclear cisterna and clumping of chromatin. The second stage included dissolution of the nuclear envelope and passage of nuclear matrix into the cytoplasm. The third stage consisted of vacuolation of the cytoplasm and compression of the chromatin to the periphery of the cell. In the fourth stage of degeneration, the organism consisted essentially of a vacuole, and chromatin was condensed into an irregular mass of clumped material.

Animals↗
PubMed1979

Herpesvirus-like infection of the venom gland of Siamese cobras.

The light and electron microscopic appearance of venom glands from two Siamese cobra snakes with a history of production of poor-quality venom was determined. Light microscopy revealed degeneration and necrosis of patches of columnar epithelial cells of glands and infiltration of the subepithelium by inflammatory cells. The lumina contained debris, venom, and necrotic cells. Electron microscopy revealed a deficiency of microvilli on the luminal surfaces of both degenerated and necrotic epithelial cells. The lumina contained fragmented microvilli, coated vesicles containing venom, and degenerated and necrotic cells. Naked and enveloped herpesvirus-like particles were seen in necrotic and ruptured cells. Occasionally, naked herpesvirus-like particles were seen in the nuclei of attached epithelial cells. It was concluded that herpesvirus-like infection of the venom gland was the probable cause of the production of poor-quality venom.

Animals↗
PubMed1979

Ehrlichiosis in wolves, dogs, and wolf-dog crosses.

Canine ehrlichiosis was diagnosed in wolves, dogs, and wolf-dog crosses at a small zoo in northcentral Florida. Five of 9 adult canids and all 8 pups confined to a common kennel died as a result of the infection. The epizootic was associated with a massive Rhipicephalus sanguineus infestation. Hematologic and pathologic findings in an adult wolf-dog cross that died were characteristic of canine ehrlichiosis. That animal and four other canids were seropositive for Ehrlichia canis. No deaths occurred following the oral treatment of remaining canids with tetracycline hydrochloride and the treatment of canids and premises with acaricides.

Animals↗
PubMed1979

Ectopic calcification in lambs from feeding the plant Cestrum diurnum.

Hypercalcemia and ectopic calcification were induced in 5 lambs by supplementing the diet with the dried leaves of the plant Cestrum diurnum, for 8 to 9 weeks. Lambs developed mineralization of blood vessels, heart, kidneys, and lungs. These tissues were examined by light and electron microscopy. In the vascular tissue there was calcification of elastic fibers in the hyperplastic intima and the media, along with mineralization of mitochondria of aortic smooth muscle cells. Myocardial cells and their mitochondria were mineralized. In the kidney, there was calcification of the epithelium of the distal convoluted tubules and collecting tubules, Bowman's capsule, and the mesangial cells of the glomeruli. In the lung, there was mineralization of the alveolar septal walls and the bronchi and bronchioles. Feeding of the calcinogenic plant to lambs caused extensive soft tissue calcification. Results of the study indicated that degeneration was the early soft tissue lesion in this plant toxicity.

Animals↗
PubMed1979

Serum and body characteristics of laying hens with fatty liver syndrome.

Commercial laying hens with Fatty Liver Syndrome had greatly elevated levels of serum calcium and cholesterol. Most of the hens with the elevated serum calcium and cholesterol were out of production, but some were still in production. Hens with elevated calcium and cholesterol levels had extremely large combs and excessive deposits of fat in the abdomen.

Adipose Tissue↗
PubMed1979

Hepatitis, cardiomyopathy and hemodynamics in furazolidone-induced round heart disease of turkeys.

Twenty-five large broad-breasted white turkeys were fed a 22% protein diet supplemented with 500 ppm furazolidone from day 1 to 3.5 weeks of age and the same diet supplemented with 700 ppm furazolidone until 9.5 weeks of age. Following the development of round heart disease as indicated by altered electrocardiograms the 25 turkeys were sacrificed. In the livers of turkeys with biventricular dilatation (72% of cases) there was bile duct hyperlasia, portal fibrosis and intracytoplasmic globules in the hepatocytes. Globules stained pink with hematoxylin-eosin, deep red with PAS and variable with Massons trichrome stains in paraffin-embedded liver sections. Clear intracytoplasmic vacuoles demonstrable in hepatocytes of PAS stained liver sections embedded in paraffin did not stain as lipid in frozen sections but did contain sparse flocculent material in 1 micrometer sections of liver embedded in epoxy resin and stained with toluidine blue. At the subcellular level, the intracytoplasmic globules in hepatocytes were surrounded by a single membrane, contained flocculent material and had enzymatic properties characteristic of lysosomes. Blood pressure, heart rate, dp/dt max, total plasma proteins and plasma trypsin inhibitory capacity of turkeys with round heart disease were lower than corresponding values for control turkeys. Control turkeys did not exhibit the characteristic gross or microscopic lesions of round heart disease.

Animals↗
PubMed1978

Relation of hemodynamics to the incidence of diethylstilbestrol-induced aortic ruptures in hypertensive and hypotensive lines of turkeys.

Hypertensive and hypotensive lines of turkeys were treated with diethylstilbestrol (DES) alone, or with DES and propranolol (PROP). Untreated turkeys of each blood pressure line served as controls. Mortality rate from aortic ruptures was highest (43.7%) in the hypertensive line treated with DES, but mortality was reduced to 7.7% when this line of turkey was treated with both DES and PROP. Among the hypotensive line of turkeys treated with DES, 26.7% died of aortic ruptures, but none died when these turkeys were treated with DES and PROP. Propranolol did not influence serum cholesterol levels, and all DES or DES and PROP treated birds had greatly elevated values, as contrasted to untreated turkeys. Aortic lipid values were highest in the hypotensive line of turkeys treated with DES, but, by histologic evaluation, aortic atherosclerosis was equally severe in all DES-treated turkeys. Blood pressure and aortic dp/dt max were higher in the hypertensive line treated with DES than in the similarly treated hypotensive line. This probably accounted for the higher mortality in the former group. Absence of significant mortality in either line of turkey following treatment with both DES and PROP apparently resulted from the decreased stress on the aorta caused by lowering of blood pressure and aortic dp/dt max by PROP.

Animals↗