PubMed Health⌕ Search

Biomedical subjects

N G Wright

Publications and source records attributed to N G Wright.

At least 19 recordsLinked to original sources
PubMed1992

Changes in atrial natriuretic factor and plasma renin activity in dogs infected with Trypanosoma brucei.

When beagle dogs were infected with Trypanosoma brucei, a marked reduction in the plasma concentration of atrial natriuretic factor (ANF) occurred in the terminal stage of the disease during weeks 3 and 4. At the same time there was an increase in plasma renin activity (PRA) after infection. Ultrastructural studies of the atria of these dogs demonstrated a reduction in ANF granules. The changes in ANF and PRA occurred in association with severe pancarditis and the development of heart failure. By impairing the ability of the heart and kidneys to regulate blood volume, the alterations in ANF and PRA could be involved in the pathogenesis of heart failure in T. brucei-infected dogs.

Animals↗
PubMed1990

A scanning electron microscopic study of the equine upper respiratory tract.

The surface features of the upper respiratory tract of 20 clinically normal horses of various ages and types were studied with scanning electron microscopy. In the rostral part of the nasal cavity, there was a wide zone of non-ciliated epithelium whereas, caudally, the surface was well ciliated. This latter type of epithelium extended into the nasopharynx and guttural pouches although scattered areas of non-ciliated microvillous cells were also found.

Animals↗
PubMed1990

An ultrastructural study of the equine lower respiratory tract.

The surface features of the lower respiratory tract of 20 clinically normal horses of different ages and types were studied with scanning electron microscopy. Parallel light microscopical and transmission electron microscopical studies were also carried out. The ciliary carpet was virtually complete from the trachea to the lobar bronchi. In small bronchi, ciliation was less complete allowing numerous non-ciliated mucous cells to become obvious. The terminal bronchioles, populated mainly by non-ciliated bronchiolar epithelial cells, had an abrupt junction with alveolar ducts. Interalveolar pores were common particularly in older horses.

Animals↗
PubMed1990

Experimental immune complex glomerulonephritis and the nephrotic syndrome in cats immunised with cationised bovine serum albumin.

Membranous nephropathy was induced in four cats by repeated intravenous injections of 120 mg cationic bovine serum albumin (BSA, pI 9.5). All four cats developed diffuse granular deposits of IgG and C3 along the glomerular capillary walls as early as five weeks which persisted until the end of the experiment at 17 weeks. Ultrastructural studies revealed many subepithelial electron dense deposits. Two cats developed severe proteinuria and the nephrotic syndrome characterised by hypoalbuminaemia and oedema. An additional four cats received repeated injections of unmodified native BSA (pI 4.5) and remained basically normal. This is the first report of membranous nephropathy and the nephrotic syndrome in an experimental animal model which, unlike other animal models, is subject to the spontaneously occurring disease.

Animals↗
PubMed1979

Membranous nephropathy in the cat: a clinical and pathological study.

A series of 13 cases of feline membranous nephropathy is presented. Two groups were distinguished clinically; eight cats had the nephrotic syndrome and five others were in renal failure but not nephrotic. The definitive diagnosis was based on histological, immunofluorescence and ultrastructural examinations of renal tissue obtained at renal biopsy or necropsy. Glomerular lesions were classified according to the degree of glomerular change into three distinct groups; mild, moderately severe and advanced. A relationship was established between the mild and moderately severe groups and cats with the nephrotic syndrome, and the advanced group and cats in renal failure. Diuretic therapy was satisfactory in initial control of oedema in the nephrotic cases. Monitoring of previously nephrotic cats for up to three years indicated that the disease is progressive, although in some cases it is sufficiently slow for a cat to live a relatively normal life without continuing treatment. The prognosis for cats presented in renal failure is hopeless.

Animals↗
PubMed1978

Vaccination against canine bordetellosis: protection from contact challenge.

Eight collie-cross pups, eight weeks old, were inoculated intramuscularly with an aluminum hydroxide adjuvanted preparation of killed Bordetella bronchiseptica; the inoculation was repeated after two weeks. Two weeks after the second inoculation, the vaccinated dogs and a control group of four unvaccinated animals were placed in contact with a group of five pups of similar age which had been experimentally infected with a pathogenic strain of B bronchiseptica by an aerosol method. All four unvaccinated control dogs as well as all five experimentally infected dogs developed a respiratory disease characterised by persistent coughing. Six of the vaccinated dogs remained free from clinical respiratory disease while disease was less severe and of shorter duration in the remaining two than in controls. Only slight changes were found in the lungs of vaccinated animals at necropsy while in the controls there was a severe tracheobronchitis. There was a marked reduction in the numbers of B bronchiseptica isolated from the respiratory tract of vaccinated animals when compared with controls. An aluminium hydroxide adjuvanted vaccine may be of value in controlling naturally occurring canine respiratory disease in which B bronchiseptica is involved.

Animals↗
PubMed1978

A study of dogs with kennel cough.

A detailed study of a population of dogs with kennel cough was undertaken. Twenty-seven (77 per cent) of a total of 35 dogs had pathological evidence of respiratory disease in the form of tracheobronchitis with, in some animals, exudative pneumonia. A variety of viral and bacterial agents were isolated from the respiratory tract of diseased dogs but Bordetella bronchiseptica and canine parainfluenza virus SV-5 appeared to be the most significant organisms recovered.

Animals↗
PubMed1978

Transmission studies with bovine malignant catarrhal fever.

The intravenous administration of whole blood from a pathologically confirmed field case of bovine malignant catarrhal fever (MCF) resulted in the appearance of the disease in three of five experimental calves 18 to 28 days later. Infection was maintained by serial calf transmissions, and produced clinical and pathological changes identical to those of the field disease for a total of 10 passages. The sixth passage involved the simultaneous infection of 10 calves from a single donor animal; six of the 10 recipients developed the typical disease after incubation periods ranging from 20 to 36 days and in each of these MCF was confirmed by pathological examination. In addition, clinical and pathological changes in the four other calves which were slaughtered either seven or 14 days post-infection suggested that they too would have developed typical clinical signs had they been allowed to survive for the necessary length of time. The results of a detailed study of the onset, progress and duration of the clinical signs of experimentally induced MCF are presented and the opportunity has been taken to discuss the available information regarding the transmission of MCF under experimental conditions and in the field.

Animals↗
PubMed1978

Vaccination against Bordetella bronchiseptica infection in dogs using a heat-killed bacterial vaccine.

A group of eight-week-old dogs was inoculated with a heat-killed suspension of Bordetella bronchiseptica by the intramuscular route on two occasions at an interval of two weeks. All vaccinated animals developed high circulating agglutinin titres by two weeks after the second inoculation at which time the vaccinated dogs and a comparable group of unvaccinated animals were challenged by exposure to an aerosol of live B bronchiseptica. Both vaccinated and unvaccinated dogs subsequently developed clinical respiratory disease characterised by persistent coughing but the onset of disease in vaccinated animals was delayed by up to five days when compared with the controls. B bronchiseptica was isolated from the nasal cavity, tracheobronchial tree and lung parenchyma of vaccinated and control dogs.

Animals↗
PubMed1978

Vaccination against canine bordetellosis using an aluminum hydroxide adjuvant vaccine.

Six collie dogs, eight weeks old, were inoculated intramuscularly with an aluminium hydroxide adjuvanted preparation of killed Bordetella bronchiseptica; the inoculation was repeated after two weeks. Two weeks after the second inoculation, the vaccinated dogs and a comparable group of six unvaccinated animals were challenged by exposure to an aerosol of pathogenic B bronchiseptica. All six unvaccinated control dogs developed respiratory disease characterised by persistent coughing. In contrast, four of the vaccinated dogs remained free from clinical respiratory disease while, in the other two dogs, disease was less severe and of shorter duration than in controls. At necropsy, there were only slight changes in the lungs of vaccinated dogs but in controls there was a severe tracheobronchitis with areas of exudative pneumonia. Bacteriological examination showed a marked reduction in the numbers of B bronchiseptica isolated from the respiratory tract of vaccinated animals compared with controls. An aluminium hydroxide adjuvant vaccine may be of value in controlling naturally occurring respiratory disease in dogs in which B bronchiseptica is involved.

Adjuvants, Immunologic↗
PubMed1976

Chronic renal failure in dogs: a comparative clinical and morphological study of chronic glomerulonephritis and chronic interstitial nephritis.

Chronic renal disease is an important clinical problem in dogs. Until recently, diffuse renal fibrosis with chronic renal failure has been attributed mainly to chronic interstitial nephritis, itself considered to be the end stage of acute leptospiral nephritis. A clinical and morphological analysis of eight cases of chronic glomerulonephritis is described and a comparison made with eight dogs suffering from severe chronic interstitial nephritis. Clinically and biochemically, the two diseases were virtually indistinguishable, both resulting in uraemia. A possible distinguishing feature of chronic interstitial nephritis was the anaemia which was absent from chronic glomerulonephritis cases. Morphologically, the two diseases appeared to be distinguishable on three grounds; the pattern and severity of fibrosis, the degree of fibrin deposition and the immunofluorescence findings.

Animals↗
PubMed1976

Canine leptospirosis: an immunopathological study of interstitial nephritis due to Leptospira canicola.

In an attempt to define the pathogenetic mechanisms involved in acute interstitial nephritis due to Leptospira canicola the kidneys of 14 dogs were subjected to histological immunofluorescence and elution studies. Leptospiral antigen was found in three sites within the kidney; as discrete organisms in the proximal tubules, as granular deposits in the cytoplasm of macrophages and in large extracellular clumps in the interstitium. Deposits of IgG were also detected in the latter site and in plasma cells found in the surrounding cellular infiltrate. Anti-leptospiral antibody, mainly of the IgG class, was detected in renal eluates using both agglutination-lysis and indirect immunofluorescence. From these findings it was considered that the cellular infiltrates found in the kidneys of dogs suffering from acute leptospiral nephritis have two main functions; firstly, the local production of anti-leptospiral antibody and, secondly, phagocytosis.

Animals↗
PubMed1976

An immunopathologic study of interstitial nephritis associated with experimental canine adenovirus infection.

The localisation of canine adenovirus in the renal tubules induces a marked cellular response in the interstitium. A number of mechanisms appear to be involved in the genesis of the lesions. Direct lytic damage to tubular epithelial cells by the virus is probably augmented by immunological factors. The production of local anti-viral antibody by plasma cells in the vicinity of virus-containing cells may result in the formation of toxic antigen-antibody complexes while the accumulation of large populations of macrophages suggests that cell-mediated hypersensitivity is also operative.

Adenoviridae Infections↗