Neuromuscular disease in dogs: some aspects of its investigation and diagnosis

The techniques used in clinical investigation of muscle disease are discussed with particular reference to the use of EMG and muscle biopsy. Cryostat sections of muscle are used for rapid diagnosis but their main function is for the performance of investigative enzyme histochemistry. A brief review of the commoner diseases of muscle is presented, the material being obtained principally from the Veterinary Surgery Department at Glasgow. These diseases include neurogenic disorders, muscular dystrophy and various inflammatory diseases. It is suggested that a large number of myopathies occur in dogs which will be revealed by further studies. Examples of these are myopathies in association with malignancies. It is emphasized that for an accurate and complete investigation clinical, biochemical, electrical and pathological studies must be performed on the cases presented. Résumé. Les techniques employées dans l'investigation clinique des maladies musculaires sont traitées particulièrement en référence avec L'utilisation de l'électromyogramme et de la biopsie musculaire. Les coupes microscopiques cryostatiques du muscle permettent d'établir un rapide diagnostique, mais leur fonction principale réside dans la recherche histochimique sur les enzymes. Les maladies musculaires les plus communes sont rapidement passées en revue, les matériaux provenant en majeure partie du Département de Chirurgie Vétérinaire de Glasgow. Ces maladies comprennent les troubles neurogènes, l'atrophie musculaire et diverses troubles inflammatoires. Il est suggéré que, chez les chiens, se trouve un grand nombre de myopathies qui pourront ětre révélées par des études plus approfondies. Pour que l'investigation soit exacte et complète, il est absolument indispensable de procéder à la fois aux études biologique clinique, électrique et pathologique dans chacun des cas présentés. Zusammenfassung. Die Techniken, die man in klinischer Erforschung von Muskelerkrankung anwendet, sind diskustert mit besonderem Hinweis auf den Gebrauch von EMG und Muskelbiop-sie. Kryostat Sektionen von Muskeln werden fur schnelle Diagnosen gebraucht, aber ihre Haupt-funktion ist fur die Ausfuhrung von erforschender Enzym-Histochemie. Ein kurzer Uberlick von allgemeinen Muskelkrankheiten wird dargelegt, das Material erhielt man hauptsǎchlich von der Veterinaren Chirurgie Abteilung in Glasgow. Dièse Krankheiten schliessen nervursprùngliche Stǒrungen, Muskelschwund und verschiedene Entziindungskrankheiten ein. Es wird angedeutet, dass eine gross Anzahl von Muskelleiden in Hunden vorkommt, welche sich durch weitere Studien zeigen werden. Beispiele von diesen sind Muskelleiden in Verbindung mit Malignitàten. Man mǒchte besonders betonen, dass fiir eine genaue und komplette Erforschung klinisch biochemische, elektrische und pathologische Studien von Fall zu Fall ausgefiihrt werden mǔssen.     

A radiochemical and gas-chromatographic study of the determination of dichlorvos residues in stored grain

An investigation into the extraction of dichlorvos from stored grain and satisfactory storage conditions for samples received for analysis has been carried out using [³²P]-dichlorvos. It has been shown that samples can be effectively stored at —17° C and that methanol can be used for the extractable dichlorvos but does not remove the organophosphorus residue bound to the grain.     

Biological effects of combining carboxin,organomercury fungicides and insecticides as seed dressings for wheat,and the effect of these combinations on adherence of the pesticides to the seed

When seeds of winter wheat were carefully dressed in the laboratory with combinations of fungicides (organomercury alone or organomercury plus the systemic fungicide carboxin) and insecticides (aldrin, carbophenothion or chlorfenvinphos as liquid formulations, or a γ-BHC powder formulation) so as to ensure that nearly all the recommended amounts of the active ingredients stuck to them, the insecticides gave good insect control, but γ-BHC with organomercury fungicide decreased the number of plants that germinated, and γ-BHC with carboxin and organomercury was even more damaging. Commercially dressed seeds had only about 30 to 60% of the target dose of fungicides, but more than 80% of the target doses of the liquid insecticides aldrin, carbophenothion and chlorfenvinphos. With combinations of powder fungicide and liquid insecticide, greater amounts of pesticide on the seed were obtained if the insecticide was put on first. Because of unusually late sowings and little fungal infestation, neither laboratory nor commercially treated seeds provided good tests for control of smut.     

Spontaneous laryngeal paralysis in four white-coated German shepherd dogs

Four cases of spontaneous laryngeal paralysis in juvenile white-coated German shepherd dogs are described. The presenting signs were typical for laryngeal paralysis, with stridor present in all four cases. Laryngoscopy revealed bilateral laryngeal paralysis in three cases, and unilateral paralysis in one. Concurrent megaoesophagus was also identified in one dog. All dogs underwent surgical treatment for laryngeal paralysis. Euthanasia was performed in one case due to intractable regurgitation and aspiration pneumonia. A possible association with white coat colour is discussed.     

Central nervous system pathology in 25 dogs with chronic degenerative radiculomyelopathy

The neuropathology of 20 German shepherd dogs and five German shepherd dog crosses with chronic degenerative radiculomyelopathy were analysed by conventional techniques, immunocytochemistry and electron microscopy. There were previously unrecognised changes in brain nuclei. In the spinal cord, both motor and sensory tracts were involved, principally in their more distal regions. Wallerian degeneration affected the corticorubrospinal pathways in the lateral columns and the ventral funiculi, predominantly in the caudal thoracic and lumbar segments, although more cranial involvement was also observed. The dorsal columns were affected in the caudal lumbar region and the cervical fasciculus gracilis. The regional distribution was variable between cases. Within the brain, abnormalities, including chromatolysis, gliosis and neuronal loss were observed in the red nucleus, lateral vestibular nucleus and, occasionally, in the dentate nucleus. The changes in brain nuclei were compared with those found in dogs at various times after a focal spinal injury. The neuronal changes in the brain may be related to the primary site of damage, and possible aetiological mechanisms are discussed.     

Positive regulation of T cell activation and integrin adhesion by the adapter Fyb/Slap

The molecular adapter Fyb/Slap regulates signaling downstream of the T cell receptor (TCR), but whether it plays a positive or negative role is controversial. We demonstrate that Fyb/Slap-deficient T cells exhibit defective proliferation and cytokine production in response to TCR stimulation. Fyb/Slap is also required in vivo for T cell-dependent immune responses. Functionally, Fyb/Slap has no apparent role in the activation of known TCR signaling pathways, F-actin polymerization, or TCR clustering. Rather, Fyb/Slap regulates TCR-induced integrin clustering and adhesion. Thus, Fyb/Slap is the first molecular adapter to be identified that couples TCR stimulation to the avidity modulation of integrins governing T cell adhesion.