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Biomedical subjects

R D Jolly

Publications and source records attributed to R D Jolly.

At least 109 records · Page 6Linked to original sources
PubMed1977

Polioencephalomalacia of dogs with thiamine deficiency.

A naturally occurring neurological disease occurred in six dogs fed cooked meat. Clinical signs were anorexia, progressive spastic paraparesis, recumbency, convulsions and death. The disease was characterized by bilaterally symmetrical spongy change and necrosis of brainstem nuclei with a lesion distribution pattern similar to that in thiamine deficient foxes and cats. An associated thiamine deficiency was evidenced by decreased thiamine levels in the blood of one dog and in the food of another, and rapid remission of clinical signs in a dog given thiamine hydrochloride. Thermal destruction of thiamine through cooking of the foods probably caused the dietary deficiency.

Animals↗
PubMed1977

Generalized glycogenosis in beef shorthorn cattle--heterozygote detection.

A preliminary study of acidic alpha-glucosidase in a variety of tissues was carried out in an attempt to develop a test which might be used to detect individuals heterozygous for the genetype associated with generalized glycogenosis in beef Shorthorn cattle. Of the tissues readily available peripheral lymphocytes were chosen as being likely to be the most suitable. It was concluded that, when coupled with genealogical information, assays of alpha-glucosidase in extracts of lymphocytes were useful for identifying heterozygous individuals with a reasonably high degree of probability.

Animals↗
PubMed1976

The nature of the residual alpha-mannosidase in plasma in bovine mannosidosis.

Acidic alpha-mannosidase (EC 3.2.1.24), optimum pH 4.25, is absent from the plasma of Angus calves with mannosidosis, and the residual alpha-mannosidase activity has an optimum pH of 5.5, intermediate between that of the acidic and neutral alpha-mannosidases. This 'intermediate' alpha-mannosidase differs from the acidic form in its kinetic properties, its lack of marked inhibition by EDTA and its thermolability at 55 degrees C and physiological pH. Isoelectric focusing and ion-exchange chromatography show that it exists in at least two forms. The presence of a secondary peak at pH 5.5 in the pH/activity profile of normal plasma and the effect of heating at 55 degrees C indicate that such a form is present in normal plasma. The residual activity in the plasma of a calf with mannosidosis is therefore probably not the product of the defective gene. A differential assay, based on their different stabilities at 55 degrees C, has been developed for measuring the acidic and intermediate alpha-mannosidases in plasma. There was no correlation between the concentrations of the two enzymes in the plasma of Angus cows heterozygous for mannosidosis or in the plasma of normal animals. This precludes the use of the intermediate form as a reference enzyme for the acidic activity in a test for heterozygosity for mannosidosis based on the gene-dosage phenomenon. The concentrations of the intermediate activity were comparable in normal animals and animals homozygous or heterozygous for mannosidosis.

Animals↗
PubMed1976

Enzyme replacement therapy--an experiment of nature in a chimeric mannosidosis calf.

Enzyme replacement therapy was studied in a chimeric mannosidosis calf which had received a natural transplacental transplant of normal lymphocytes from its co-twin. There was considerable reduction in the pathology of certain organs and in the amount of storage oligosaccharides, but the clinical course of this neurologic disease was not significantly altered. It was postulated that if this disease had been purely visceral the transplant would have been relatively effective.

Animals↗
PubMed1975

A urinary pentasaccharide in bovine mannosidosis.

Abnormally high amounts of low molecular weight mannose-rich carbohydrate material were found in the urine of an Angus calf with mannosidosis. At least five oligosaccharide fractions were detected by paper chromatography. The most abundant compound was purified by gel chromatography, zone electrophoresis, and two consecutive preparative paper chromatographic steps. The yield was 10 mg/liter of urine. From structural studies including nuclear magnetic resonance spectroscopy, optical rotation, sugar analysis, methylation analysis, and partial enzymatic degradation the following structure was deduced: alpha-D-Manp-(1 leads to 6)-beta-D-Manp-(1 leads to 4)-beta-D-GlcNAcp-(1 leads to 4)-beta-D-GlcNAcp-(1 leads to 4)-D-GlcNAc. This oligosaccharide is distinct from all the oligosaccharides previously described which are excreted by patients with mannosidosis.

Acetylglucosamine↗
PubMed1974

Mannosidosis in Angus cattle. The enzymic defect.

Normal calf alpha-mannosidase activity exists in at least three forms separable by chromatography on DEAE-cellulose and by starch-gel electrophoresis. Two components, A and B, have optimum activity between pH3.75 and 4.75, but component C has an optimum of pH6.6. Components A and B are virtually absent from the tissues of a calf with mannosidosis and the residual activity is due to component C. The acidic and neutral forms of alpha-mannosidase differ in their molecular weights and sensitivity to EDTA, Zn(2+), Co(2+) and Mn(2+). An acidic alpha-mannosidase component (pH optimum 4.0) accounts for most of the activity in normal plasma but it is absent from the plasma of a calf with mannosidosis. Although the acidic alpha-mannosidase component is probably related to tissue components A and B, it can be distinguished from them by ion-exchange chromatography and gel filtration. The optimum pH of the low residual activity in the plasma from a calf with mannosidosis is pH5.5-5.75. The results support the hypothesis that Angus-cattle mannosidosis is a storage disease caused by a deficiency of lysosomal acidic alpha-mannosidase activity.

Animals↗