Amylopectinosis in fetal and neonatal Quarter Horses.

Three Quarter Horses, a stillborn filly (horse No. 1), a female fetus aborted at approximately 6 months of gestation (horse No. 2), and a 1-month-old colt that had been weak at birth (horse No. 3), had myopathy characterized histologically by large spherical or ovoid inclusions in skeletal and cardiac myofibers. Smaller inclusions were also found in brain and spinal cord and in some cells of all other tissues examined. These inclusions were basophilic, red-purple after staining with periodic acid-Schiff (both before and after digestion with diastase), and moderately dark blue after staining with toluidine blue. The inclusions did not react when stained with Congo red. Staining with iodine ranged from pale blue to black. Their ultrastructural appearance varied from amorphous to somewhat filamentous. On the basis of staining characteristics and diastase resistance, we concluded that these inclusions contained amylopectin. A distinctly different kind of inclusion material was also present in skeletal muscle and tongue of horse Nos. 1 and 3. These inclusions were crystalline with a sharply defined ultrastructural periodicity. The crystals were eosinophilic and very dark blue when stained with toluidine blue but did not stain with iodine. Crystals sometimes occurred freely within the myofibers but more often were encased by deposits of amylopectin. This combination of histologic and ultrastructural features characterizes a previously unreported storage disease in fetal and neonatal Quarter Horses, with findings similar to those of glycogen storage disease type IV. We speculate that a severe inherited loss of glycogen brancher enzyme activity may be responsible for these findings. The relation of amylopectinosis to the death of the foals is unknown.

Intestinal multinodular A lambda-amyloid deposition associated with extramedullary plasmacytoma in three dogs: clinicopathological and immunohistochemical studies.

Intestinal extramedullary plasmacytomas (EMPs) are rare tumours in dogs. Three cases of canine intestinal EMP with amyloid deposits are described in this report. These tumours, which were located in the rectal submucosa, had variable numbers of well-differentiated plasma cells and fewer multinucleated giant cells of plasmacytoid and histiocytic morphology, admixed with abundant amyloid. Two cases had metaplastic cartilage and bone within the amyloid deposits. Immunohistochemically, the plasma cells of all three tumours reacted for lambda-light chains of immunoglobulins but not for kappa-chains, indicating monoclonality. Plasma cells of two tumours were also positive to CD79a antiserum. Amyloid deposits were labelled with an A lambda (amyloid of immunoglobulin lambda-light chain origin) antiserum but not with antisera against its precursor protein, the immunoglobulin lambda-light chains, indicating possible conformational changes of amyloidogenic proteins during their transformation into amyloid.

Caprine mucopolysaccharidosis-IIID: clinical, biochemical, morphological and immunohistochemical characteristics.

Several animal models have been developed for the mucopolysaccharidoses (MPSs), a group of lysosomal storage disorders caused by lysosomal hydrolase deficiencies that disrupt the catabolism of glycosaminoglycans (GAG). Among the MPS, the MPS-III (Sanfilippo) syndromes lacked an animal counterpart until recently. In this investigation of caprine MPS-IIID, the clinical, biochemical, morphological, and immunohistochemical studies revealed severe and mild phenotypes like those observed in human MPS III syndromes. Both forms of caprine MPS IIID result from a nonsense mutation and consequent deficiency of lysosomal N-acetylglucosamine 6-sulfatase (G6S) activity and are associated with tissue storage and urinary excretion of heparan sulfate (HS). Using special stains, immunohistochemistry, and electron microscopy, secondary lysosomes filled with GAG were identified in most tissues from affected goats. Primary neuronal accumulation of HS and the secondary storage of gangliosides were observed in the central nervous system (CNS) of these animals. In addition, morphological changes in the CNS such as neuritic expansions and other neuronal alterations that may have functional significance were also seen. The spectrum of lesions was greater in the severe form of caprine MPS IIID and included mild cartilaginous, bony, and corneal lesions. The more pronounced neurological deficits in the severe form were partly related to a greater extent of CNS dysmyelination. These findings demonstrate that caprine MPS IIID is a suitable animal model for the investigation of therapeutic strategies for MPS III syndromes.

Intestinal extramedullary plasmacytoma associated with amyloid deposition in three dogs: an ultrastructural and immunoelectron microscopic study.

Samples from rectal plasmacytoma in three adult dogs that were diagnosed by light microscopy and immunohistochemistry were examined by electron microscopy. The most common cell type had typical plasmacytoid features. A second cell type was a plasmacytoid giant cell with single or multiple eccentric nuclei, irregular nuclear membrane, abundant and dilated rough endoplasmic reticulum, and numerous electron-dense granules. The third cell type was a histiocytic giant cell that intermingled with plasmacytoid cells. All three tumors had abundant amyloid, mainly in the interstitium but also within histiocytic cells and less commonly in plasma cells or plasmacytoid giant cells. Extracellular and intracellular amyloid fibrils and the contents of membrane-bound electron-dense bodies of plasma cells reacted with antibody to lambda-light chain of immunoglobulins by immunogold staining.

Caprine beta-mannosidosis. Abnormal thyroid structure and function in a lysosomal storage disease.

Deficient activity of the lysosomal enzyme beta-mannosidase leads to widespread tissue accumulation of oligosaccharides in caprine beta-mannosidosis, an autosomal recessive neurovisceral storage disease. Severe thyroid morphologic abnormalities found in a previous light microscopic survey of tissues from neonatal affected goats suggested the possibility of impairment of function. Since considerable evidence indicates that thyroid hormone plays an important role in regulation of myelination, thyroid hormone deficiency, if present during central nervous system development, could be a factor in the hypomyelination seen in affected animals. Thus, this study was designed to characterize thyroid structure and function in beta-mannosidosis. To investigate developmental aspects of structural abnormalities, thyroids from six pairs of affected and control animals ranging in age from 96/150 days gestation to 3 days postnatal were analyzed by light and electron microscopy. Major findings in thyroids from affected animals, as early as 96/150 days gestation, included follicle irregularities and pronounced presence of lysosomal storage vacuoles in all cell types, particularly in follicular cells. The degree of cytoplasmic vacuolation increased with advancing age. To assess thyroid function, thyroid hormone concentrations were determined in six age-matched, neonatal pairs of affected and control goats. Significantly decreased thyroid hormone concentrations were present in affected animals. It is hypothesized that thyroid hormone deficiency plays a role in the pathogenesis of hypomyelination in affected animals. This study comprises, to our knowledge, both the most complete description of developmental abnormalities and the first report of abnormal function in an endocrine organ in a lysosomal storage disease. Further, this report suggests that systemic perturbations induced by a genetically determined deficiency of a lysosomal hydrolase could be a factor in the pathogenesis of central nervous system lesions.

Steroid estrogen conjugates in hens' urine II. Identifications of some minor conversion products of intramuscularly injected [4(-14C)]estrone.

[4(-14C)]Estrone was injected intramuscularly into two mature laying Rhode Island Red hens. Radioactive steroids and steroid conjugates recovered from the urine on Amberlite XAD-2 columns were fractionated on columns (100 cm) of DEAE-Sephadex A-25 by NaC1 gradients. The presence of the following were confirmed, the figures in brackets indicating average proportions as per cent of total radioactivity recovered after Sephadex column chromatography:-the 3-beta-glucuronides of estrone (10.9) and of estradiol-17alpha plus estradiol-17beta(9.8): the 17-beta-glucuronides of estradiol-17alpha plus estradiol-17beta (2.1); the 3-sulfates of estrone (14.5) and of estradiol-17alpha plus estradiol-17beta(27.4); and the disulfates of estradiol-17alpha plus estradiol-17beta (2.3). The following additional conjugates were identified:-a beta-glucuronide of 16-epiestriol (0.2) and a beta-glucuronide of 16-keto-estradiol-17beta (0.2); the 3-sulfates of 16-epiestriol (1.4), of 17-epiestriol (0.9), of 16,17-epiestriol (0.7), of 16-keto-estradiol-17beta (1.1), and of 2-methoxyestrone (0.7). Some evidence was obtained for the presence of 16,17-epoxy-estratrienol-3-sulfate (1.9).

Radioactive conversion products of intramuscularly injected [4-14C]formononetin including sulfates in the urine of hens.

The phytoestrogen formononetin was injected intramuscularly as [4-14C]formononetin into two adult hens. Radioactive materials in the urine for the succeeding 14 days (hen 1) or 16 days (hen 2) were fractionated on DEAE-Sephadex-25 columns by elution with a gradient of NaCl; the four major fractions thus separated were examined by solvent partition, thin-layer chromatography, and enzymic cleavage. The following seven radioactive components were identified in the urine, the average proportions of each being given in terms of percentage of total 14C recovered from the urine: [14C]formononetin (4.3%); [14C]diaidzein (11.4%); [14C]equol (6.8%); [14C]daidzein monosulfate (30.4%); [14C]equol monosulfate (5.8%); [14C]diadzein disulfate (19.8%); and [14C]equol disulfate (6.5%). Small proportions of sulfates of unidentified radioactive phenols were present. Tests for presence of glucosiduronates of 14C-labelled material gave negative results. Radioactive formononetin sulfate was not detected in the urine of either hen.

A note on amounts of [14C] in laying hens' blood after intramuscular administration of [4-14C]-estrone.

[4-14C]-Estrone in 2 ml. ethylene glycol was injected into the breast muscles of S.C. White Leghorn laying hens and the amounts of plasma [14C] per ml. whole blood were measured at various times thereafter. Maximal values were observed at 30 to 50 minutes after injection. The values then declined logarithmically with time and with a half-life of about 80 minutes between 40 and 270 minutes after injection.

Identification of radioactive 17beta-estradiol-17-beta-D-glucuronide and 17alpha-estradiol-17-beta-D-glucuronide in the urine of the domestic fowl after intramuscular injection of [4-14C]estrone.

Two previously uncharacterized radioactive estrogen conjugates, 17beta-estradiol-17-beta-D-glucuronide (3-hydroxyestra-1,3,5(10)-trien-17beta-D-glucopyranosiduronate) and 17alpha-estradiol-17beta-D-glucuronide (3-hydroxyestra-1,3,5(10)-trien-17alpha-yl-beta-D-glucopyranosiduronate), have been identified in small but significant amounts in avian urine and in a ratio of approximately 2:1 after intramuscular injection of [4-14C]estrone.

Identifications of radioactive steroid estrogen conjugates in blood plasma of laying hens after intramuscular injection of (4--14C)-estrone.

[4--14C] Estrone was injected intramuscularly into six laying hens. Fifty minutes later the hens were exsanguinated. The plasmas were examined for conjugates of radioactive phenolic steroids by recovery on columns of Amberlite XAD-2 or by extraction with tetrahydrofuran followed by chromatography on a column of DEAE-Sephadex A-25 in a gradient of NaCl. The biggest Sephadex chromatographic fraction (50,4% of total) contained about 42% of its radioactivity as estradiol-17alpha-3-sulfate and 18% as estradiol-17beta-3-sulfate and the remaining 40% was identified tentatively as estradiol-17alpha-17-sulfate plus a small proportion of estradiol-17beta-17-sulfate. The second biggest Sephadex chromatographic fraction (12.7% of total) was a mixture of conjugates not further identified. Minor fractions identified comprised estrone-beta-glucuronide (2.8%), estradiol-17alpha-3-beta-glucuronide (2.8%), estradiol-17beta-3-beta-glucuronide (2.3%) and estrone sulfate (6.0%). Evidence was obtained for the presence of small proportions of estradiol-17alpha disulfate and estradiol-17beta disulfate.

Excretion of radioactive diadzein and equol as monosulfates and disulfates in the urine of the laying hen.

The phytoestrogen, diadzein, was injected intramuscularly as [4-14-C]daidzein into two laying hens. The radioactive materials in the urine for the succeeding 23 (hen 1) or 14 (hen 2) days were fractionated on a DEAE-Sephadex column by a gradient of NaCl and the fractions thus separated were further analyzed by solvent partition, susceptability to enzymic cleavage and thin-layer chromatography. The sic following components were identified and quantitated: [14-C]diadzein, [14-C]equol, [14-C]diadzein monosulfate, [14-C]equol monosulfate, [14-C]diazein disulfate, and [14-C]equol disulfate. The urine from hen 2 yielded also the sulfate of an unidentified conversion product of [14-C]daidzein. Repeared tests for glucuronides of [14-C]daidzein or its conversion products gave negative results, excluding the possibility that any appreciable proportion of the radioactivity in the urine was in the form of beta-glucuronide. It is concluded that the diadzein and the equol excretion in the urine of the laying hen are present for the most part as monosulfates and disulfates.