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F Murata

Publications and source records attributed to F Murata.

At least 19 recordsLinked to original sources

Immunoelectron-microscopic detection of globotriaosylceramide accumulated in the skin of patients with Fabry disease.

BACKGROUND: Fabry disease is characterized by the systemic accumulation of glycosphingolipids, particularly in the lysosomes of vascular endothelial cells of most organs due to the deficient activity of alpha-galactosidase A. The major glycolipid accumulated in tissue is globotriaosylceramide (GL-3). To date, no direct detection of GL-3 by immunoelectron microscopy has been reported. OBJECTIVES: To examine whether GL-3 is accumulated exclusively in lysosomes of cutaneous cells using an anti-GL-3 monoclonal antibody (mAb) and immunoelectron microscopy. METHODS: Skin specimens from seven patients with Fabry disease were examined immunohistochemically by light and electron microscopy using an anti-GL-3 mAb. RESULTS: By light microscopy, the cytoplasm of vascular endothelial cells, eccrine gland cells, and perineurium was stained with mouse anti-GL-3 antibody. Electron microscopically, positive signals for GL-3 were limited to dilated lysosomes in the cytoplasm of endothelial cells, pericytes, eccrine gland cells, dermal fibroblasts and perineurium. CONCLUSIONS: Our results demonstrate that the cytoplasmic deposit in Fabry disease was GL-3 and the accumulated GL-3 was localized essentially to lysosomes.

Adolescent↗

Ultrastructural localization of basigin in normal human epidermis.

Basigin is a glycosylated transmembrane protein belonging to the immunoglobulin superfamily. It is thought to play roles in intercellular recognition involved in cell differentiation. We previously demonstrated at the light microscope level a correlation between basigin expression and epidermal differentiation. In the present study, the ultrastructural localization of basigin in normal human epidermal keratinocytes was investigated by immunoelectron microscopy. The basigin labeling was strongest on membranes of basal cells, weaker on prickle cells, and absent in granular and horny cells. On the membrane of basal cells, labeling was observed on the apical and lateral sides but not on the dermal side. Gold particles were mostly observed on the surface of microvilli, especially on their tips. There were fewer on the intermicrovillous membrane and they were absent on the desmosome. These results are consistent with our previous report that basigin expression is correlated with differentiation of epidermal keratinocytes. Microvilli on basal and suprabasal keratinocytes might play roles in the differentiation of keratinocytes through basigin on the tips of microvilli.

Adult↗

Expression of epithelial growth factor receptor and its two ligands, transforming growth factor-alpha and epithelial growth factor, in normal and neoplastic squamous cells in the vulva: an immunohistochemical study.

Epithelial growth factor receptor (EGFR) sends signals to the proliferation signal transduction system, receiving two ligands: epithelial growth factor (EGF) and transforming growth factor-alpha (TGF-alpha). This immunohistochemical study examined the roles of EGFR and its ligands in the proliferation of normal and neoplastic vulvar squamous cells in 25 patients with vulvar squamous cell carcinoma (VSCC), 10 patients with vulvar condyloma acuminata (VCA), 15 patients with vulvar intra-epithelial neoplasm I-II or III (VIN I-II or III), and 5 subjects with vulvar normal squamous cells (VNSC). EGFR was detected in a few basal cells in 40% of the VNSC, in highly dysplastic cells in 40% of the VIN III, in many neoplastic cells in 80% of the VCA, and in some malignant cells in 64% of the VSCC. EGF was seen in the cytoplasm in 20% of the VIN I-II, 100% of the VIN III, 100% of the VCA, and 100% of the VSCC. Diffuse TGF-alpha was weakly expressed in the cytoplasm in 100% of the VNSC, more intensely in 100% of the VIN and 100% of the VCA, and intensely in 100% of the VSCC. These findings led to the suggestion that the TGF-alpha-EGFR system maintains the growth of normal squamous cells and, in part, maintains the growth of dysplastic and neoplastic squamous cells in the vulva. EGF expression was an early sign of neoplasia. The expression of EGFR with overexpression of its two ligands contributed to the proliferation of dysplastic and neoplastic squamous cells in VIN III and VCA. EGFR expression appeared to contribute to essential neoplastic abnormalities in 64% of the VSCC.

Carcinoma in Situ↗

The expression of gastric H+-K+-ATPase mRNA and protein in developing rat fundic gland.

The proton pump H+-K+-ATPase is the final common pathway mediating the production and secretion of hydrochloric acid by gastric parietal cells. The present studies were undertaken to examine whether the expression of gastric H+-K+-ATPase mRNA and protein changes are associated with the development of H+-K+-ATPase activity in the rat fundic gland. H+-K+-ATPase activity was examined in rat fundic gland at different stages from gestational day 18.5 to postnatal 8 weeks. The expression of H+-K+-ATPase mRNA was detected by in situ hybridization using a digoxigenin-labelled RNA probe with a tyramide signal amplification system. The expression of H+-K+-ATPase protein was evaluated by immunoblotting and immunohistochemistry using antibodies against H+-K+-ATPase alpha- and beta-subunits. We found that H+-K+-ATPase enzyme activity was detectable from the onset of gland formation (day 19.5 of gestation) and increased with age in the developing rat fundic gland. Expression of mRNA and protein was also discernible at the same time, and a progressive increase in expressions was observed as rats developed. Our results suggested that in developing rat fundic gland, the expression of both mRNA and protein of H+-K+-ATPase increased with age in a manner that parallels the development of H+-K+-ATPase enzyme activity.

4-Nitrophenylphosphatase↗

Immunohistochemical study of MUC1 mucin in premalignant oral lesions and oral squamous cell carcinoma: association with disease progression, mode of invasion, and lymph node metastasis.

BACKGROUND: MUC1 mucin is a transmembrane, mucin-like glycoprotein encoded by the MUC1 gene. Although MUC1 expression has been identified in a variety of neoplastic tissues, to the authors' knowledge, few studies have examined MUC1 expression in premalignant and malignant oral lesions. METHODS: A total of 36 specimens of oral epithelial dysplasia, 12 carcinoma in situ (CIS) specimens and 77 specimens of oral squamous cell carcinoma (OSCC), were examined by both light and electron microscopy using immunohistochemical staining of MUC1 mucin. Relations between staining patterns and clinicopathologic findings also were examined. RESULTS: Distinct membrane MUC1 mucin staining patterns were identified in epithelial dysplasia (33.0%), CIS (50.0%), and OSCC (59.7%) cases. A predominantly cytoplasmic staining pattern was detected in epithelial dysplasia (5.6%), CIS (41.7%), and OSCC (32.5%) cases. Significant positive correlations were found between MUC1 mucin membranous immunoreactivity and disease progression from epithelial dysplasia to OSCC (P < 0.01), mode of tumor invasion (P < 0.02), and lymph node metastasis (P < 0.01). Furthermore, the malignant transformation of oral epithelium, tumor invasion, and tumor metastasis were associated with higher MUC1 mucin expression in the cytoplasm (P < 0.01). In addition to the usual cell surface expression, cytoplasmic expression of MUC1 mucin was confirmed by colloidal gold labeling with transmission electron microscopy. CONCLUSIONS: The results of the current study suggest that determination of MUC1 mucin expression may be a parameter in the diagnosis of premalignant and malignant lesions arising in the oral cavity and that this expression may affect the malignant behavior of OSCC. MUC1 mucin expression may be a useful diagnostic marker for prediction of the invasive/metastatic potential of OSCC.

Carcinoma, Squamous Cell↗

Fabry disease: ultrastructural lectin histochemical analyses of lysosomal deposits.

Fabry disease is an X-linked inborn error of glycosphingolipid catabolism resulting from a deficiency of lysosomal alpha-galactosidase activity. Globotriaosylceramide accumulates predominantly in lysosomes of various tissues. Former studies have clarified the nature of this disease, and the accumulated materials in the lysosomes have been analyzed using biochemical techniques. In the present study, transmission electron microscopy was used to reveal the fine structure of these lysosomal deposits, and sugar residues in the lysosomal deposits in Fabry disease were examined by lectin histochemistry combined with enzyme digestion. This is the first report to describe the lysosomal sugar residues in Fabry disease analyzed using lectin histochemistry at the ultrastructural level. With these techniques, we were able to detect alpha-galactosyl, beta-galactosyl and glucosyl sugar residues in the lysosomal deposits. The experimental procedures used in this study have considerable potential for use in investigations of glycolipid and glycoprotein storage diseases without the need for complex methodology and expensive materials.

Adolescent↗

Coexistence of gland mucous cell-type mucin and lysozyme in gastric gland mucous cells.

Class III mucin, identified by paradoxical concanavalin A staining, is confined to gastric gland mucous cells and is an essential component of the gastric surface mucous gel layer. The pretreatment required has hampered the application of this method to electron microscopic studies. Antibody HIK1083 reacts selectively with class III mucins. The present study was undertaken to explore, electron microscopically, the immunoreactivity of the human stomach to HIK1083. We examined normal mucosa from resected human stomachs (five cases; formalin-fixed, paraffin-embedded) and gastric biopsy specimens from patients with early gastric cancer [nine cases; glutaraldehyde- and osmium-fixed, epoxy-embedded (seven cases) and half-strength Karnovsky's solution-fixed, Lowicryl K4M-embedded (two cases)]. Immunostaining with HIK1083 and anti-lysozyme antibody was examined under light and electron microscopes. Gland mucous cells were labeled with HIK1083, and lysozyme was detected in some gland mucous cells and surface mucous cells. Electron microscopically, the secretory granules of gland mucous cells contained a single electron-dense core. HIK1083-positive mucins and lysozyme coexisted in the secretory granules of gastric gland mucous cells. HIK1083-reactive mucins and lysozyme were distributed in the matrix and in the dense core of these secretory granules, respectively. HIK1083 can be used for electron immunohistochemistry.

Antibodies↗

Expression of N-acetylglucosamine residues in developing rat fundic gland cells.

The development of rat fundic gland was studied by immunohistochemistry using a recently developed monoclonal antibody, HIK 1083, at both light and electron microscope levels. Antibody HIK 1083 recognized oligosaccharides with a non-reducing terminal alpha-linked N-acetylglucosamine (GlcNAc) residue. In the developing rat fundic gland, cells expressing alpha-GlcNAc residues were discernible from day 19.5 of gestation and continued to exist till adult. The distribution of the alpha-GlcNAc expressing cells was consistent with that described previously for cells reacting to Griffonia simplicifolia lectin (GSA-II) in all developmental stages. These cells were located at the bottom of the fundic gland when they first appeared. With the elongation and maturation of the gland, these cells moved upwards and were finally restricted in the neck region of the gland. Combining previous reports and the present electron microscopical observations, HIK 1083-positive cells in the adult rat fundic gland are mucous neck cells. The interaction between antibody HIK 1083 and GSA-II lectin was investigated. GSA-II prevented the subsequent binding of HIK 1083, while HIK 1083 did not prevent GSA-II binding to mucous neck cells. Our results suggested that alpha-GlcNAc residues exist in rat fundic gland from day 19.5 of gestation and continue to exist till adult. Cells expressing alpha-GlcNAc residues appeared as typical mucous neck cells from postnatal four weeks.

Acetylglucosamine↗

Keratan sulfate glycosaminoglycans in murine eosinophil-specific granules.

We examined the presence of sialyl glycoconjugates in specific granules from murine bone marrow eosinophils. Lectin cytochemistry using Maackia amurensis lectin II (MAL II) specific for sialyl alpha-2,3 galactose residues demonstrated positive labeling in both immature and mature specific granules. Pretreatment with Clostridium neuraminidase or keratanase II eliminated the positive labeling of MAL II in the specific granules. High iron diamine-thiocarbohydrazide-silver proteinate physical development (HID-TCH-SP-PD) staining, which is specific for sulfated glycoconjugates, also positively labeled immature specific granules lacking crystalloids but not mature granules with crystalloids. Pretreatment with a combination of chondroitinase ABC and keratanase, or a combination of chondroitinase ABC and keratanase II, eliminated the positive labeling obtained with HID-TCH-SP-PD. These results indicate that the sialyl residues detected by MAL II are expressed as terminal sugar residues of keratan sulfate proteoglycan, which appears to be of the corneal type in view of its sensitivity to keratanase and keratanase II. (J Histochem Cytochem 47:481-488, 1999)

Acetylglucosaminidase↗

Sulfated glycosaminoglycans in guinea pig neutrophils studied by use of cationic colloidal gold.

Using a high electron resolution staining method, cationic colloidal gold (CCG, pH 1.0) staining, we studied the fine structural localization of sulfated glycosaminoglycans (GAGs) in various maturational stages of guinea pig neutrophils. Azurophil and specific granules of neutrophils reacted positively to CCG, with variety in labeling according to maturation. All immature azurophil and specific granules were labeled selectively. Mature granules lost their affinity with CCG. CCG-positive labeling was also observed in the trans to trans-most Golgi apparatus of promyelocytes and myelocytes. Prior absorption with poly-l-lysine prevented CCG labeling of tissue sections. Mild methylation of ultrathin sections at 37C did not alter CCG labeling, whereas CCG labeling disappeared after active methylation at 60C. Treatment with chondroitinase ABC or heparinase I abolished the majority of CCG labeling. These findings suggest the existence of sulfated GAGs not only in immature azurophil but also in immature specific granules of neutrophils. Sulfation of GAGs occurs in the trans- to trans-most Golgi apparatus of neutrophil granulocytes. A possible correlation between accumulation of sulfated GAGs and maturation of specific granules in neutrophils is also discussed.

Animals↗

Ontogeny of the rat parietal cell: analysis using anti-parietal cell antibody and transmission electron microscopy.

We studied the ontogeny of the rat parietal cell using human anti-parietal cell antibody and transmission electron microscopy. In the gastric fundus of the rat, we found that the epithelium changed from stratified to columnar at gestational day 18.5. Gastric pits began to form at gestational day 19.5. Primitive fundic glands appeared at gestational day 20.5. Human anti-parietal cell antibody specifically stained the rat parietal cells. By this immunohistochemical staining, rat parietal cells were identified from gestational day 19.5. At first we observed only a few plump parietal cells sparsely located in the fundic glands. In neonatal rats, the parietal cells increased in number and began to distribute themselves over a wider area of the primitive fundic glands especially in the lower half. As the rats grew, the distribution area of the parietal cells expanded to cover the whole of the glands except for the foveolar region. Parietal cells in the isthmus and neck regions were round and plump, while those in the basal region were slender and polygonal. We found that throughout the development of the fundic glands there were several ultrastructural changes of the parietal cells. In the late fetal period, parietal cells containing lysosomes and secretory granules were observed, but no tubulovesicles were identified. Development of the tubulovesicles was remarkable until one week after birth. The ultrastructure of the parietal cells of the neonate and adult varied, depending on their distribution area. We found that parietal cells in the basal region of the fundic glands which are fully matured cells had wider intracellular secretory canaliculi, while cells in the upper region had narrower canaliculi; this indicates the functional difference between hydrochloric acid secretion in parietal cells of the two regions.

Aged↗

Immunohistochemical detection of activin A, follistatin, and activin receptors during fracture healing in the rat.

Activins are multifunctional proteins that belong to the transforming growth factor-beta superfamily and are thought to play an important role in modulating the formation of bone. Activins exert their cellular effects by way of activin type-I and type-II serine/threonine kinase receptors. Follistatin is an activin-binding protein that can suppress the biological effects of activins. In this study, the immunohistochemical expression of activin A, follistatin, and activin receptors was studied during fracture healing in the rat. Activin A was weakly detected in the periosteum near the fracture ends at an early stage but was absent in the chondrocytes around the fracture gap, where endochondral ossification took place. An antibody to follistatin stained osteogenic cells in the periosteum near the fracture ends; moderate and strong staining were observed in proliferating, mature, and hypertrophied chondrocytes at the sites of endochondral ossification. Levels of activin A and follistatin were high near the osteoblasts on the surface of the newly formed trabecular bone. In addition, an intense localization of activin A was noted where multinucleated osteoclast-like cells were present. This study suggests that the activin-follistatin system may contribute to cellular events related to the formation and remodeling of bone during fracture healing. Activin type-I and type-II receptors were co-expressed in intramembranous and endochondral ossification sites. The expression of activin type-I, type-II, and type-IIB receptors in the absence of activin A in the endochondral ossification suggests that other isoforms of activins may signal by way of these receptors.

Activin Receptors↗

Sulfated glycosaminoglycans in guinea pig basophils studied by means of cationic colloidal gold.

Bone marrow embedding in the hydrophilic resin, Lowicryl K4M, followed by cationic colloidal gold (CCG, pH 1.0) staining was used to study the sulfated glycosaminoglycans (GAGs) and their sites of sulfation ultrastructurally in various maturational stages of both basophil granulocytes and basophil granules in the guinea pig. CCG at pH 1.0 is specific for sulfated GAG staining. Basophil granulocytes and granules reacted positively to CCG with a variety of staining according to the stage of maturation. The formation of basophil granules takes place throughout the myelocyte stage. Early basophil myelocytes contain a large Golgi apparatus with active granulogenesis, while late myelocytes contain a small and less active Golgi apparatus as judged by CCG staining. All the immature granules and some of the granules with characteristic ultrastructure stained positively. However, some of the mature granules had lost their affinity for CCG upon maturation. Interestingly, strongly positive CCG staining was also observed in the trans to transmost Golgi apparatus. This indicates that sulfation of GAGs occurs in the trans to transmost Golgi apparatus in all maturational stages of basophil granulocytes. Treatment with chondroitinase ABC or heparinase I abolished the majority of CCG staining.

Animals↗

Immunocytochemistry and in situ hybridization studies of pepsinogen C-producing cells in developing rat fundic glands.

The ontogeny of pepsinogen C-producing cells in rat fundic glands was studied by means of light and electron microscopy using an antiserum raised against a synthetic peptide based on rat pepsinogen C. To confirm the immunocytochemistry results, the expression of rat pepsinogen C messenger RNA (mRNA) in the fundic gland was also examined by in situ hybridization using a digoxigenin-labeled RNA probe. In adult rats, pepsinogen C was produced by chief cells, mucous neck cells, and intermediate mucopeptic cells. Pepsinogen C-producing cells appeared in embryos as early as 18.5 days' gestation. The development of these cells could be classified into four stages: (1) 18.5 days' gestation to 0.5 days after birth; (2) 0.5 days to 2 weeks after birth; (3) 3-4 weeks after birth; (4) 4-8 weeks after birth. In embryos and young animals, pepsinogen C-producing cells were mucopeptic cells. By 4 weeks after birth, mucous neck cells could be distinguished morphologically. The maturation stages of the chief cells could be traced by electron microscopy along the longitudinal axis of the rat fundic gland by double-staining with anti-pepsinogen C antibody and periodic acid-thiocarbohydrazide-silver proteinate. Positive reactions for pepsinogen C and pepsinogen C mRNA expression were detected in mucous neck cells. Therefore, we conclude that mucous neck cells are precursor cells of chief cells. Mucous neck cells, intermediate cells, and chief cells are in the same differentiating cell lineage.

Animals↗

Sulphated glycosaminoglycans in guinea pig eosinophils studied by means of cationic colloidal gold.

Using bone marrow embedded in hydrophilic resin Lowicryl K4M and cationic colloidal gold pH 1.0 labelling, we studied sites of sulphation and sulphated glycosaminoglycans ultrastructurally in various maturational stages of both eosinophil granulocytes and eosinophil granules of guinea pig. Eosinophil granules reacted positively to cationic gold, the pattern of labelling varying according to the degree of cell maturation. The formation of eosinophil granules takes place throughout the myelocyte stage. Early eosinophil myelocytes contain a large Golgi apparatus with active granulogenesis, while late ones contain a small and less active Golgi apparatus. All the immature granules were labelled positively. However, mature granules with a central crystal bar lost their affinity towards colloidal gold. Interestingly, strong colloidal gold labelling was also observed in the trans to transmost Golgi apparatus, especially in immature eosinophil granulocytes. This indicates that sulphation of glycosaminoglycans occurs in the trans to transmost Golgi apparatus of eosinophil granulocytes. Prior absorption with poly-L-lysine prevented colloidal gold labelling of tissue sections. Methylation of sections at 37 degrees C did not alter the gold labelling, whereas the labelling disappeared after methylation at 60 degrees C. Prior treatment with chondroitinase ABC or heparinase I abolished the majority of colloidal gold labelling in immature eosinophil granules. Taking these results together, we conclude that immature eosinophil granules contain sulphated glycosaminoglycans including chondroitin sulphate or heparan sulphate or both.

Animals↗

Alternate activity in the synergistic muscles during prolonged low-level contractions.

The purpose of this study was to investigate the functional interrelationship between synergistic muscle activities during low-level fatiguing contractions. Six human subjects performed static and dynamic contractions at an ankle joint angle of 110 degrees plantar flexion and within the range of 90-110 degrees (anatomic position = 90 degrees) under constant load (10% maximal voluntary contraction) for 210 min. Surface electromyogram records from lateral gastrocnemius (LG), medial gastrocnemius (MG), and soleus (Sol) muscles showed high and silent activities alternately in the three muscles and a complementary and alternate activity between muscles in the time course. In the second half of all exercise times, the number of changes in activity increased significantly (P < 0.05) in each muscle. The ratios of active to silent periods of electromyogram activity were significantly higher (P < 0.05) in MG (4.5 +/- 2.2) and Sol (4.3 +/- 2.8) than in the LG (0.4 +/- 0.1), but no significant differences were observed between MG and Sol. These results suggest that the relative activation of synergistic motor pools are not constant during a low-level fatiguing task.

Adult↗

Novel method to investigate kinetics of rat skin cells by means of an occlusive dressing method using bromodeoxyuridine.

We developed a novel technique to detect S-phase skin cells by applying bromodeoxyuridine (BrdU) epicutaneously using an occlusive dressing (OD) method. BrdU was scarcely absorbed from the skin with a simple epicutaneous application, whereas the incorporation of BrdU was very well promoted with the use of our OD method. We applied BrdU on the backs of rats using this method and investigated the conditions required for an optimal response, with a special focus on the period of application, the concentration of BrdU used and vehicles suitable for the immunocytochemical staining of this agent. From these experiments, we were able to determine that an application time of at least 60 min was necessary to liable S-phase cells, a 2% concentration of BrdU was needed to obtain consistent labeling and aqueous vehicles are satisfactory solvents for BrdU preparations. Epidermal keratinocytes and S-phase cells in the upper portion of dermis were clearly labeled after either intraperitoneal injection of BrdU or after administration by means of the OD method. To ascertain whether this latter method could provide an effective alternative to intraperitoneal injection, we compared the labeling patterns of both methods with respect to the speed of migration of BrdU-labeled basal cells from the basal layer to the horny layer of epidermis. Using either of these two methods, basal keratinocytes were labeled immediately after administration. Three days after the first administration, BrdU-labeled cells were detected in the middle layer of the epidermis, but after 8 days, they were no longer evident in epidermal tissue. As another means of comparing both methods, we used antibody to proliferating cell nuclear antigen (PCNA) and compared the ratio of PCNA-positive basal cells to BrdU-labeled basal cells. The number of PCNA-positive cells was about 4.6 times greater than the number of BrdU-labeled basal cells by both methods. We concluded that the OD method could be used as a substitute for intraperitoneal injection in order to observe cell kinetics using bromodeoxyuridine.

Administration, Topical↗

Cationic colloidal gold staining of acidic glycoconjugates in mouse Paneth cells.

The acidic glycoconjugates of mouse ileum Paneth cells were examined with the aid of light and electron microscopy, using cationic colloidal gold (CCG) as a probe. Specimens of mouse ilea were fixed in half-strength Karnovsky's fixative and embedded in Lowicryl K4M resin. Semithin and ultrathin sections were cut of examination with light and electron microscopy, respectively. Examination of the sections using light microscopy revealed the positive staining of CCG at pH 1.0 and pH 2.5, which was detected at the rim of secretory granules and at the supranuclear regions of the Paneth cells. At pH 4.0, in addition to staining of the secretory granule rim, weak staining was observed in the granule core. At pH 7.2, the cytoplasm other than secretory granules exhibited positive CCG staining. Examination of the sections using electron microscopy, at pH 1.0, the trans lamellae of the Golgi apparatus, the rim of the secretory granules, and lysosomes were labeled selectively by CCG. At pH 2.5, labeling was also discernible over the same structures in the cells. However, at this pH, the labeling intensity was stronger than that at pH 1.0, due to the dual labeling of sulfated and sialylated glycoconjugates in these structures. At pH 4.0, the Golgi apparatus, rims and cores of secretory granules and ribosomes were labeled. Lysosomes and nuclei were also positively stained. At pH 7.2, the rims of secretory granules were not stained. The present results indicate that the CCG method gives good resolution and contrast when applied to staining, and therefore is useful for the specific staining of glycoconjugates such as sulfated, sialylated and phosphated glycoconjugates for light and electron microscopy.

Animals↗