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Biomedical subjects

F Murata

Publications and source records attributed to F Murata.

At least 55 records · Page 3Linked to original sources

Ultracytochemistry of glycoconjugates in rat Brunner's gland with labeled lectins.

Mucous glycoproteins of rat Brunner's gland were examined ultracytochemically to elucidate the intracellular localization and sites of glycosylation in relation to the functional polarity of the cell organellae using a combination of hydrophilic resin embedment and postembedding staining with labeled lectins. A few cis cisternae were stained with HPA (Helix pomatia agglutinin, specific for terminal alpha-N-acetylgalactosamine) and DBA (Dolichos biflorus aggulutinin, specific for terminal alpha-N-acetylgalactosamine). Trans cisternae as well as cisternae following secretory granules were stained with HPA and RCA-I (Recinus communis agglutinin I, specific for terminal beta-galactose). UEA-I (Ulex europaeus agglutinin I, specific for terminal alpha-L-fucose) seemed to bind to transmost cisternae rather than trans cisternae. HPA bound to the whole cisternae, but to the cis or trans cisternae depending on a cell type. Apical mucous granules were stained with UEA-I, RCA-I, and HPA, but not with DBA. DGA seemed to be a good marker of the cis side of the Golgi apparatus and cell membrane. The glycosylation of mucous glycoprotein in rat Brunner's gland was partly clarified electron microscopically.

Animals↗

Nasu-Hakola disease (membranous lipodystrophy). Clinical, histopathological and biochemical studies of three cases.

We report 3 cases of Nasu-Hakola disease found in 2 families. These cases had identical clinical features with progressive spastic paraplegia and severe dementia after adolescence. They had no history of any skeletal symptoms, but roentgenographs of their bones presented characteristic evidence of polycystic osteodysplasia. All cases revealed not only manifestations of this condition in the central nervous system, but also peripheral neuropathy with axonal degeneration. The membranous structures in the adipose tissues appeared histochemically to be composed of a kind of compound glycolipid or glycoprotein. Histopathologically, the biopsied rectum showed the infiltration of many histiocytes in the mucosa and ultrastructurally, the granules in these histiocytes showed many membrane-bound vacuoles of different sizes. Interestingly, the histochemical reactivity of the material in the granules was very similar to that of membranous structures in adipose tissues. In the biochemical analysis of lipids in affected adipose tissues, no marked abnormalities were found in the patients. Nasu-Hakola disease is not a typical form of lysosomal storage disease, because lysosomal enzyme activities remain normal and there is no accumulation of urinary oligosaccharides and lipids, no vacuolation of lymphocytes, and no hepatosplenomegaly. However, histochemical findings suggest that the lysosomes may be secondarily involved in this disease, and that the formation of membranous structures might be related to the disturbance of glycolipid or glycoprotein metabolisms.

Adipose Tissue↗

Glycoconjugate histochemistry of the rat fundic gland using Griffonia simplicifolia agglutinin-II during the development.

The development and maturation of fundic glands of Wistar rats were studied using Griffonia simplicifolia agglutinin-II (GSA-II) histochemistry at the light microscopic and electron microscopic levels. In adult rats, mucous neck cells and cells intermediate between mucous neck cells and chief cells were specifically labeled with GSA-II, whereas other fundic gland cells were virtually negative. Ontogenetic studies revealed that GSA-II positive cells appeared at the bottom of the gland by 21 days of gestation. With differentiation and aging, the elongation of the fundic gland continued, and the labeling intensity of the mucous neck cells increased by 3 weeks after birth. Cells intermediate between mucous neck cells and chief cells were discernible from 3 days after birth. Typical mucous neck cells appeared at 3 weeks after birth, when their labeling intensity with colloidal gold (CG) particles approximated that of adults. On the other hand, the reactive cell population gradually moved from the bottom toward the middle portion of the gland. Finally, the reactive cells were localized at the neck portion of the fundic gland. These results suggest that GSA-II is a valuable marker for studying mucous neck cells and both their precursor cells and their derivatives.

Acetylglucosamine↗

Ultrastructural demonstration of Maclura pomifera agglutinin binding sites in the membranocystic lesions of membranous lipodystrophy (Nasu-Hakola disease).

This paper reports three cases of membranous lipodystrophy (Nasu-Hakola disease) in two families and studies the carbohydrate components of membranocystic lesions in all three cases, using twelve kinds of lectins labelled by horseradish peroxidase (HRP). Maclura pomifera agglutinin (MPA), which specifically binds alpha-D-galactose residues, strongly stained typical membranocystic lesions, whereas the other lectins did not. However, Helix pomatia agglutinin (HPA), which specifically binds to N-acetyl-D-galactosamine (GalNAc), stained the membranes of degenerated adipose cells. These were thought to appear during the initial or early stage of the membranocystic lesions. This suggests that a change of carbohydrate residues occurs during the formation of the membranocystic lesions. We also investigated the lectin binding sites at the ultrastructural level using MPA-HRP colloidal gold (CG) conjugate. In the well developed membrane, CG particles were arranged regularly along the minute tubular structures. On the other hand, there were a few irregularly spaced CG particles on the thinner membranes and also on the membranes of the degenerating adipose cells. No CG particles labelled the cell membranes of normal adipose cells. The presence of alpha-D-galactose residues in the membranocystic lesions is demonstrated for the first time at the electron microscopic level.

Adipose Tissue↗

Purification and properties of N-acetylglucosaminide beta 1----4 galactosyltransferase from embryonal carcinoma cells.

N-Acetylglucosaminide beta 1----4 galactosyltransferase was chromatographically purified about 1,700-fold from F9 embryonal carcinoma cells after solubilization with Triton X-100, using N-acetylglucosamine as the acceptor. As the last step of the purification, affinity chromatography was performed either on N-acetylglucosamine-Sepharose or on alpha-lactalbumin-Sepharose: in both cases, two protein bands with molecular weights of around 68,000 and 59,000 were detected by SDS-polyacrylamide gel electrophoresis of the purified preparations. The enzymological properties including behavior toward alpha-lactalbumin were very similar to those of the enzyme from other sources. The specificity of the enzyme was confirmed by determining the structure of the product; it was mostly Gal beta 1----4GlcNAc. beta-Galactosidase-treated embryoglycan (poly-N-acetyllactosamine) and asialo-agalactofetuin could serve as acceptors with the purified enzyme. Thus, the embryonic enzyme, apparently involved in the synthesis of poly-N-acetyllactosamines, has properties similar in several respects to those of the beta-galactosyltransferases so far studied.

Animals↗

Ultrastructural localization of lectin receptors in the monkey retinal photoreceptors and pigment epithelium: application of lectin-gold complexes on thin sections.

The cell surface and intracellular binding sites of two lectins, wheat germ agglutinin (WGA) and Ricinus communis agglutinin-1 (RCA-1), in the monkey retina were investigated at the ultrastructural level by means of post-embedding staining of Lowicryl K4M-embedded specimens with lectin-colloidal gold complexes. Effects of pretreatment with neuraminidase were also studied. The techniques enabled us to detect lectin binding sites in the various intracellular compartments of photoreceptor cells, retinal pigment epithelium (RPE), and interphotoreceptor matrices. Wheat germ agglutinin, which recognizes N-acetylglucosamine and sialic-acid residues, showed a prominent and uniform binding to the disc membranes of rod outer segments (ROS), rod connecting cilia, interphotoreceptor matrices, and RPE microvilli. The intensity of these binding sites was markedly reduced when thin sections were pretreated with neuraminidase, except the labeling of ROS disc membranes. Cones were labeled sparsely. The staining of phagosomes in the RPE cytoplasm did not change after neuraminidase digestion. RCA-1, which recognizes galactose residues, revealed a moderate binding to the ROS disc membranes, with a noticeably greater intensity of binding to the basal region of ROS disc membranes. With neuraminidase treatment heavier binding with RCA-1 occurred in interphotoreceptor matrices, connecting cilia and RPE microvilli, whereas there was no significant alteration in binding to the ROS disc membranes. Phagosomes in the RPE were also labeled with this lectin. The results suggest the presence of sialic acid and galactose as the constituent carbohydrates of glycoconjugates in the interphotoreceptor matrices and RPE microvilli.

Animals↗

Glycoconjugate cytochemistry of the rat fundic gland using lectin/colloidal-gold conjugates and Lowicryl K4M. Helix pomatia lectin is a specific marker for mucous neck cells in fundic glands of the rat gastric mucosa.

The fundic gland of the rat stomach was studied using the low-temperature embedding resin Lowicryl K4M and postembedding staining with lectin/colloidal-gold (CG) conjugates. Intense labeling with Ricinus communis agglutinin I was observed not only in mucous-producing cells but also in parietal cells. In contrast, Helix pomatia agglutinin (HPA) only labeled mucous neck cells and intermediate cells between mucous neck cells and chief cells. The other epithelial cells present in the rat fundic gland showed virtually no reaction with this lectin. Our results indicate that HPA might be a marker lectin of mucous neck cells and their derivatives. The combination of embedding in the hydrophilic resin Lowicryl K4M and postembedding staining with lectin-CG conjugates provided satisfactory staining results, and made it possible to visualize the precise distribution of terminal glycoconjugates in intracellular components as well as on the plasma membrane.

Animals↗

Application of rapid freezing followed by freeze-substitution acrolein fixation for cytochemical studies of the rat stomach.

A method involving rapid freezing followed by substitution fixation was developed, using acrolein as a fixative. This was then applied to several cytochemical stainings, and showed well preserved and clear cell structures. Membranes were apparently negatively stained and the ultrastructure of mitochondria, rough endoplasmic reticulum and Golgi apparatus was clearly discernible. The mitochondrial and cytoplasmic matrices were stained rather densely compared with routine chemically fixed preparations, implying a good preservation of matrix substances. Periodic acid-thiocarbohydrazide-silver proteinate staining was applied to the present method. The mucous granules of surface covering epithelial cells indicated fine staining of bipartite structure and the Golgi apparatus of mucous cells showed clear staining differences based on polarity. Postembedding lectin-ferritin and immunocytochemical stainings were applicable to the present preparations and stable stainings of secretory granules were obtained. A low temperature embedding material, Lowicryl K4M, was also examined. The cell preservation of these samples was not as good as those embedded in Epon, but the rough endoplasmic reticulum and Golgi apparatus of chief cells were stained with anti-pepsinogen antibody as were the secretory granules. The present method was also applicable to light microscopy.

Acrolein↗

Qualitative and quantitative analysis of erythrocyte surface membrane sialyl residues using affinity cytochemistry with special reference to diabetic patients.

Erythrocyte surface membrane sialyl residues were investigated by means of affinity cytochemistry using the avidin-biotin complex technique. Mild oxidation with the periodate (MO)-biotin hydrazide (BHZ)-ferritin avidin conjugate (FAv) sequence revealed numerous ferritin particles on erythrocytes from healthy donors. The ferritin particles attached on the perpendicularly sectioned membrane were seen at an average distance of 10 to 12 nm from the outer dense leaflet of the cell membrane. Pretreatment with neuraminidase followed by the MO-BHZ-FAv sequence almost eliminated erythrocyte ferritin labeling. Erythrocytes from diabetic patients showed less dense ferritin labeling compared with those from healthy donors. Quantiative analysis of sialyl residues demonstrated a marked reduction in ferritin labeling of erythrocytes from diabetic patients which was significantly less (p less than 0.01) than that of erythrocytes from healthy donors. This observation supports previous biochemical data demonstrating lower levels of surface membrane negative charge and sialyl residues on erythrocytes from patients with diabetes mellitus.

Adult↗

Adult fucosidosis: histochemical and ultrastructural studies of rectal mucosa biopsy.

Three sisters with adult fucosidosis showed prominent psychomotor retardation, gargoyle features, and angiokeratoma corporis diffusum, meeting the criteria for type II fucosidosis. By histochemical and ultrastructural studies, biopsy of rectal mucosa revealed many abnormal macrophages that were filled with fucose-rich granules, and electronmicroscopic examination showed several types of characteristic inclusions in the endothelial cells, fibroblasts, and Schwann's cells.

Adult↗

Lectin-peroxidase reactivity in rat gastric mucosa.

The localization of lectin-binding sites in the rat gastric mucosa was investigated using horseradish peroxidase-labeled lectin conjugates (Con A, DBA, PNA, RCA-1, SBA, UEA-1, WGA). The glandular epithelium of the cardiac gland was clearly stained with DBA, PNA and SBA. Surface epithelium of the fundic glands was intensely labeled with SBA and UEA-1, but weakly with RCA-1, and WGA. Staining for foveolar cells was intense with SBA and moderate with PNA, while Con A and RCA-1 showed negligible reactivity. Mucous neck cells were intensely stained with SBA, moderately with PNA, weakly with Con A, RCA-1 and WGA, and only, faintly with DBA. Chief cells reacted positively only with WGA. Surface epithelium of the pyloric gland was moderately labeled with DBA, SBA and WGA, and faintly with the other lectins. Glandular epithelial cells, which revealed a similar pattern to that of the surface epithelium, were stained more intensely. The present study provides additional information for elucidating the cellular and regional differences in lectin binding to the rat gastric mucosa.

Animals↗

Differential expression of lectin receptors in germ layers of the mouse egg cylinder and teratocarcinomas.

Receptors for three lectins with restricted specificities, namely fucose-binding protein of Lotus tetragonolobus (FBP), peanut agglutinin (PNA) and Dolichos biflorus agglutinin (DBA), were distinctively located in 6- and 7-day mouse embryos and in embryoid bodies of teratocarcinoma OTT6050 grown in vivo. Thus, FBP reacted mainly with the inner cells (embryonic ectoderm and teratocarcinoma stem cells), DBA reacted with the outer cells (endoderm) and PNA reacted with all the germ layers including mesoderm. Upon in vitro culture of the embryoid bodies, the exposed stem cells express DBA receptors. Since the receptors for the three lectins in teratocarcinomas are known to be carried by the large carbohydrate chains characteristic of early embryonic cells, the present result suggests that terminal structure of the large carbohydrates is altered according to the direction of the differentiation or to the position of the cells in embryos and in teratocarcinomas.

Amnion↗

Cells intermediate between mucous neck cells and chief cells in rat stomach.

Morphological and histochemical methods revealed cells intermediate between mucous neck cells and chief cells in rat stomach. The secretory granules of mucous neck cells and chief cells were homogeneous. However, some cells resembling mucous neck cells in shape and size yet contained heterogeneous granules. One type of cell contained mucous granules showing a bipartite structure. The inner cores of these granules resembled the granules of mucous neck cells morphologically and after staining by the periodic acid-thiocarbohydrazide-silver proteinate (PA-TCH-SP) procedure and lectin-ferritin methods. The outer layer of these granules, however, resembled the granules of chief cells and failed to stain by these methods. Another type of cell also contained bipartite granules, but these showed a dense cap and lucent matrix. The cap of the granules did not stain with the PA-TCH-SP and lectin methods, but the remaining matrix was reactive. These presumed transitional cells were located in a layer between the mucous neck cells and the chief cells. Immature chief cells with sparse granular reticulum were found near these intermediate cells in some cases. Many similar intermediate type cells were also found in early developmental stages of the gastric mucosa in rat. These results suggest a close relationship between chief cells and mucous neck cells; chief cells may develop from undifferentiated stem cells via mucous neck cells in adult rat stomach.

Animals↗

Immunocytochemical localization of pepsinogen in rat stomach.

The localization of pepsinogen in rat stomachs was investigated by a postembedding immunoferritin method. When the preparations embedded in Epon were used, the secretory granules of chief cells were stained heavily and the granules of mucous neck cells were stained moderately. The secretory granules of cells intermediate between mucous neck cells and chief cells showed a bizonal staining; the electron dense parts were stained heavily and the electron lucent parts were stained moderately. The secretory granules of pyloric gland cells, on the other hand, were labeled faintly. However, the secretory granules of surface mucous cells, foveolar mucous cells, endocrine cells, cardiac mucous cells and cardiac serous cells were not stained by the method. The protein A-gold method showed a similar staining pattern of pepsinogen to that of the immunoferritin method. When the samples embedded in Lowicryl K4M were used to enhance the stainability of pepsinogen, essentially the same staining pattern as that of the samples embedded in Epon was obtained. In addition, the Golgi apparatus and the rough surfaced endoplasmic reticulum were more easily stained.

Animals↗

Distribution of glycoconjugates in the kidney studied by use of labeled lectins.

Distribution of glycoconjugates in different areas of the rat kidney was studied by light and electron microscopy using six different horseradish peroxidase-labeled lectins. Glomeruli and brush borders of the proximal tubules reacted differently to these lectins, which indicated differences in the carbohydrate compositions of those regions. The ascending limb of Henle's loop (ALH) had strong binding sites for peanut agglutinin (PNA) and soybean agglutinin (SBA). Dolichos biflorus agglutinin (DBA) did not stain the cells of ALH but did stain those of distal convoluted tubules (DCT). DBA is a good marker for distinguishing ALH from DCT. DBA, PNA, and SBA were also good markers of the collecting duct. Ricinus communis agglutinin (RCA-1) and wheat germ agglutinin (WGA) diffusely stained the various components of different parts of the kidney.

Animals↗