Clinical course of renal adenocarcinoma associated with hypercupraemia in a horse

A four-year-old shire mare with haematuria, colic, terminal weight loss and an abdominal mass had a large unilateral renal adenocarcinoma. Clinical signs were monitored for 11 months. Increased serum copper concentrations were measured on two occasions. Hypercupraemia is discussed as a possible paraneoplastic change.

Endometrial carcinoma in a young dog

A 2-years-old nulliparous cross-bred bitch had persistent vulval discharge following treatments that included a combined ethinyloestradiol/methyltestosterone preparation and megoestrol acetate. The uterus, removed at ovarohysterectomy, contained a large polypoid intraluminal mass with the histological features of endometrial carcinoma. The bitch has remained well for thirty-one months after surgery. The possibility is considered that the lesion is drug-related but no firm conclusion can be drawn about the precise nature and pathogenesis of this unusual lesion.

The immune response to Echinococcus granulosus: sequential histological observations of lymphoreticular and connective tissues during early murine infection

This paper describes the organ weight changes and the early (0 to 56 days) histological and ultrastructural changes in the lymphoid structures and injection sites after subcutaneous infection of Balb/c mice with Echinococcus granulosus protoscolices (psc). Local lymph nodes enlarged markedly, reaching maximal weight 5 to 14 days after infection (pi). Expansion of the thymus-dependent areas of draining lymph nodes was first recognized at 3 days pi and reached a maximum between 14 and 21 days pi. Lymphoproliferation within B-cell-dependent areas was less extensive and of shorter duration. Comparable, but diminished, changes were seen in contralateral lymph nodes and spleen. Lymphoid cell depletion was observed in T-dependent areas of lymphoid organs by 56 days pi. Local inflammatory reactions to psc, at the site of injection, were intense, involving neutrophils, eosinophils, macrophages and mast cells. Viable psc were present until at least 6 weeks pi. The central role of the T-lymphocyte in recognition of, and response, to E. granulosus psc is discussed.

Histological changes following Nd YAG laser photocoagulation of canine gastric mucosa

Tissue changes produced in the dog stomach by exposure to a Nd YAG laser varied from mild mucosal oedema to cell vaporisation. Intermediate degrees of damage caused a marked inflammatory response leading to extensive fibrosis in the submucosa and muscularis propria. The true extent of tissue damage was not apparent immediately, and treated mucosa that initially appeared intact sometimes sloughed several days later to leave an ulcer. The extent of damage and the rate of healing depended on the amount of laser energy used. With pulses at optimum laser power (75 w) and exposure time (0.4 sec), however, haemostasis was achieved in induced ulcers with total energy concentrations that did not produce full thickness tissue damage nor alter the healing rate from that observed in untreated ulcers. Thermal contraction was the primary haemostatic mechanism, thrombosis only occurring as a secondary effect.

Experimental pyelonephritis in the cat: 3. Collagen alterations in renal fibrosis

Chronic pyelonephritis was induced in young adult cats by the intravenous injection of a human or a feline strain of Escherichia coli after ligation of one ureter for 24 or 48 h. In the 3 cats infected with the feline strain, scarred kidneys from the obstructed side were removed at necropsy 3, 4 and 5 months later. Collagen was extracted from pyelonephritic and normal kidney tissue with dilute acetic acid and limited proteolysis with pepsin. Scarred kidneys gave higher yields of both acid-soluble collagen (normal = 0.57 +/- 0.12 mg per g tissue; scarred = 0.88 +/- 0.10 mg per g tissue) and pepsin-solubilized collagen (normal = 9.69 +/- 1.79 mg per g tissue; scarred = 20.02 +/- 2.84 mg per g tissue). There was no significant increase in the collagen yield from the kidneys of the 2 cats in which mild focal lesions were found 14 and 16 months after infection with the human strain of E. coli. Pepsin released collagens were separated by fractional salt precipitation and identified by agarose gel chromatography and polyacrylamide gel electrophoresis. Normal kidney was shown to contain collagen of Types I, IV and V (AB). The Type IV collagen extracted consisted of a mixture of 4 major pepsin-resistant chains of apparent molecular weights of 150 000, 115 000, 85 000 and 60 000. The collagen extracted from scarred kidneys was predominantly Type I, only trace amounts of Type IV and V components being present. These findings suggest that basement membrane collagens of the kidney are selectively degraded during the atrophy and scarring of chronic feline pyelonephritis and are preferentially replaced by interstitial Type I collagen.

Hepatic beta galactosidase and feline GMI gangliosidosis

This paper describes the clinical, morphological and biochemical features of three cats with a progressive neurological disorder. Clinical features were ataxia and progressive tremor. The morphological characteristics were those of lysosomal storage disease affecting neurones of the central nervous system and autonomic ganglia; membranous cytoplasmic bodies were demonstrated by electron microscopy in cerebral neurones. Chemical analysis of brain from two of the cats revealed an increased content of total gangliosides, sialic acid and a specific increase in GMI ganglioside. Enzyme analysis of homogenates of leucocytes, spleen and brain showed less than 5% or normal 4-methylumbelliferyl-beta galactosidase (4MU-beta gal) activity. In liver, activity was markedly reduced at pH values below 4.2, but there was considerable activity above this value. The properties of 4MU-beta gal in normal and diseased feline livers were investigated. Sephadex gel filtration of diseased liver homogenates showed an absence of two thermolabile "acid' components, and reduced activity of a third thermostable "neutral' component. The biochemical abnormalities found in the diseased cats are similar to those found in human juvenile GMI gangliosidosis (type 2).

Nature and extent of histological changes induced by argon laser photocoagulation in canine gastric mucosa

The tissue changes in canine gastric mucosa caused by exposure to an argon laser beam vary from mild mucosal oedema to complete cell destruction. Intermediate degrees of damage cause an inflammatory cell response with the formation of granulation tissue, particularly in the submucosa. The rate of healing is similar to that after other forms of injury to the gastric mucosa. Cell destruction at the surface of the mucosa starts with energies greater than 8 Joules on any one spot, and occurs at greater depths as the energy is increased but, unless cells are actually destroyed, the extent of histological damage is limited to a zone 1 mm lateral to, or below, the area exposed to the laser beam. Haemostasis is achieved by thermal contraction of bleeding vessels and of the surrounding tissue, thrombosis only occurring as a secondary effect.

NdYAG laser photocoagulation in the dog stomach

Considerable discussion still centres around the relative merits of the Argon and Neodymium Yttrium Aluminum Garnet (NdYAG) lasers for the endoscopic treatment of gastrointestinal haemorrhage, although both are undoubtedly effect. We have carried out experiments to elucidate which factors determine the safety and efficacy of NdYAG laser photocoagulation. Histological studies on normal gastric mucosa showed that the depth of tissue damage depended mainly on the total incident laser energy, whereas the effectiveness of photocoagulation of induced gastric ulcers in heparinised animals depended on the laser power and the exposure time used. Optimum haemostasis with minimum tissue damage was obtained using pulses of 300 to 500 ms duration with energies of 25 to 40 J. We consider these parameters safe and effective for use in pilot clinical studies.

Optic neuropathy in a horse

A 10-month-old thoroughbred colt developed sudden complete blindness; no other neurological abnormality was detected. At necropsy 3.5 months later lesions were confined to both optic pathways in which there was extensive degeneration of axons and myelin and gliosis. The cause of the optic lesion was not determined but the lesion may be a toxic neuropathy.

Argon laser photocoagulation in the dog stomach

Laser photocoagulation is one of a number of methods currently under investigation for the endoscopic treatment of gastrointestinal haemorrhage. The Argon ion and Neodymium Yttrium Aluminium Garnet (Nd YAG) lasers are theoretically suitable as the beam from each may be transmitted via a flexible fibre. Argon laser photocoagulation has been shown to be effective and we have elucidated which factors determine its safety and efficacy. Studies on normal canine gastric mucosa showed that the depth of tissue damage depended chiefly on the total incident laser energy on any one spot, and that below 50 J the risk of perforation was extremely low. The energy density was much less important. The haemostatic effect depended more on the laser power. In artificial bleeding gastric ulcers in heparinised dogs the most effective level was 7--9 W, at which 22 out of 23 ulcers (96%) stopped bleeding completely, compared with one out of 12 controls. Photocoagulation was achieved in these cases with energies well within the safe limits. The procedure was effective endoscopically, and these results justify early clinical studies in man.

Megaloesophagus and associated gastric heterotopia in the cat

Two young adult male Siamese cats had heterotopic gastric mucosa in the dilated and inflamed oesophagi. Normally differentiated gastric mucosal glands were present and there was severe ulceration in one cat. It is uncertain whether the gastric heterotopia was a reparative change after oesophagitis or whether it represented a coincidental anatomical anomaly.

A lymphomatoid granulomatosis of the lungs in young dogs

Clinical signs in three young dogs with primary lung neoplasms included cough, weight loss and anorexia. Chest radiographs taken in the terminal stages of the disease showed nodular and diffuse consolidation of the lungs typical of primary neoplasms. Macroscopically the lungs were infiltrated by firm, pale tissue; similar tissue replaced the enlarged bronchial lymph nodes. In two dogs similar deposits were found also in the liver and spleen. The infiltrates were composed of atypical, polymorphous lymphoreticular cells. Invasion of pulmonary blood vessels and of bronchi and bronchioles was striking. The lesions closely resembled those of lymphomatoid granulomatosis, a rare human disease of unknown cause.

Histology of salivary gland infarction in the dog

Salivary gland infarction was found in two adult dogs. The main changes were ischaemic necrosis, capsular fibrosis and regenerative hyperplasia of surviving ductal epithelium. Necrosis of arterial tunica media and thrombosis were found only in the infarcted parts of the salivary glands. The lesions appeared to be confined to the salivary glands; no cause of the infarction was found.

Skin ulceration associated with herpesvirus infection in cats

Three cases of skin ulceration in cats are described. Herpesvirus was isolated from the ulcers. Treatment of one case with antibiotics and an antiviral agent was successful. The significance of the viral isolate is discussed.