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Biomedical subjects

F Murata

Publications and source records attributed to F Murata.

At least 37 records · Page 2Linked to original sources

[Lectin histochemistry of the glycoconjugates in conjunctival goblet cells].

The distribution of O- and N-linked glycoconjugates in human conjunctival goblet cells was examined histochemically using biotinylated and fluorescence-labeled lectins simultaneously. Both peanut agglutinin and Erythrina cristagalli agglutinin, specific for O- and N-linked sugar chains, respectively, bound to the same goblet cell, which demonstrated that a conjunctival goblet cell produces and contains both types of glycoconjugates. Maackia amurensis lectin II, specific for sialic acid alpha 2, 3 galactose, bound to the goblet cells, while Sambueus nigra agglutinin, specific for sialic acid alpha 2, 6 galactose, did not. This observation suggested that the terminal galactosyl residue of the glycoconjugates is alpha 2, 3-sialylated in the human conjunctival goblet cells.

Conjunctiva↗

Proliferation and migration kinetics of stem cells in the rat fundic gland.

The proliferation and migration of stem cells in the developing and adult rat fundic gland have been studied using BrdU immunohistochemistry and BrdU-GSA II (Griffonia-simplicifolia agglutinin-II) double staining. In the developing rat fundic gland, stem cells were first scattered throughout all levels of the epithelia and then concentrated in the depth of the pits. With the elongation and maturation of the fundic glands, stem cells left the gland base and moved upward. By 4 weeks after birth, the development of the fundic gland was completed and stem cells were confined to a narrow proliferative zone in the isthmus, reaching the adult distribution pattern. In the adult rat fundic gland, stem cells in the isthmus differentiated and migrated upward and downward, replacing the surface mucous cells and glandular cells respectively. For upward migration, it took about one week for stem cells to migrate from the isthmus to the surface. For downward migration, it took about two weeks for stem cells to migrate from the isthmus to the neck, and it took 30-36 weeks to reach the gland unit's blind end. Finally stem cells were lost at the deepest level of the glands. The results obtained by simple topographical distribution in the present experiment agreed well with those obtained by quantitative analysis, suggesting the usefulness of BrdU immunohistochemistry for cell kinetic studies.

Aging↗

Clinicopathologic and prognostic significance of an angiogenic factor, thymidine phosphorylase, in human colorectal carcinoma.

BACKGROUND: Platelet-derived endothelial cell growth factor (PD-ECGF) is known to promote the development of new blood vessels, which are fundamental to tumor growth and metastasis. We previously found that thymidine phosphorylase (dThdPase) and PD-ECGF are the same protein. PURPOSE: We retrospectively examined the expression of dThdPase in primary colorectal carcinomas, its association with angiogenesis and clinicopathologic findings, and its prognostic value. METHODS: Tissues were obtained from the tumors of 163 patients whose colorectal carcinomas were completely removed by surgery. Microvessels assessed by immunostaining endothelial cells for factor VIII were counted on a 400x field in the most active areas of neovascularization within the tumor. We purified the monoclonal antibody against dThdPase and studied the expression of dThdPase in the same serial sections used for the detection of factor VIII. Those who carried out microvessel counting and dThdPase expression assessment had no knowledge of clinicopathologic findings. The significance of dThdPase in the prognosis of patients with colorectal carcinomas was also examined in the survival analysis of mortality follow-up data covering the period between 1984 through 1991. Reported P values are from two-sided tests of statistical significance. RESULTS: The mean microvessel count (+/- standard deviation) in dThdPase-positive colorectal carcinoma specimens (17.5 +/- 7.2) was higher (P < .001) than that in dThdPase-negative carcinoma specimens (9.3 +/- 5.5). The dThdPase positivity was in accordance with the microvessel count. dThdPase positivity showed highly significant statistical associations with tumor size, extent of invasion, lymph node metastasis, lymphatic invasion, and venous invasion. Cox regression analysis revealed that dThdPase expression was prognostic for poor disease outcome after adjustment for Dukes' stage and microvessel count. CONCLUSIONS: These findings suggest that higher levels of dThdPase expression in colorectal carcinomas are associated with more extensive angiogenesis, poor clinical and laboratory findings, and unfavorable clinical outcome. IMPLICATIONS: Inhibition of dThdPase in human colorectal carcinomas might improve prognosis for some patients.

Colorectal Neoplasms↗

Ontogeny of sulphated glycoconjugate-producing cells in the rat fundic gland.

The ontogeny of sulphated glycoconjugate-producing cells in the rat fundic gland has been studied using high iron diamine (HID), Alcian Blue (AB) at pH 1.0, high iron diamine in combination with Alcian Blue at pH 2.5 (HID-AB), cationic colloidal gold (CCG) at pH 1.0 under light microscopy and CCG (1.0), HID-thiocarbohydrazide (TCH)-silver proteinate (SP)-physical development (PD) under electron microscopy. From day 19.5 of gestation, sulphated glycoconjugate-producing cells were discernible under both light and electron microscopy. The development of such cells can be classified into four stages: (1) a prenatal period from day 19.5 of gestation extending to 0.5 days after birth; (2) 1 day to 2 weeks after birth; (3) 2 to 4 weeks after birth; and (4) the final period from 4 to 8 weeks after birth. Glycoconjugate-producing cells reached maturity by 4 weeks after birth. Our results indicated that glycoconjugate-producing cells were cells along the wall of foveolar lumen, but not those covering the gastric mucosa surface. Our results also suggested that the trans to transmost Golgi apparatus lamellae were the sites of sulphation in the developing rat stomach.

Alcian Blue↗

Ontogeny of proliferative cells in the rat fundic gland.

The ontogeny of proliferative cells in the rat fundic gland was studied using bromodeoxyuridine (BrdU) immunohistochemistry from day 17.5 of gestation to 8 weeks after birth. This ontogenic process is divided into 4 stages. (1) The late fetal period extending to 0 day of birth: Proliferative cells were scattered throughout all levels of the stratified epithelium in the earliest stage (day 17.5-18.5 of gestation). With the appearance of a primitive gastric pit at day 19.5 of gestation, proliferative cells were more numerous at the base of the fundic gland. Proliferative cells were concentrated in the gland base and were rarely seen in the epithelial surface from day 21.5 of gestation onwards. (2) One day to 2 weeks after birth: As fundic gland growth proceeded, proliferative cells remained concentrated in the gland base. (3) Two to 4 weeks after birth: Proliferative cells left the gland base and moved upward to reach the adult location in the isthmus. (4) Four to 8 weeks after birth: The development of the fundic gland was complete and proliferative cells remained in a narrow proliferative zone in the isthmus.

Animals↗

Expression of Sia alpha 2-->6Gal beta 1-->4GlcNAc residues on sugar chains of glycoproteins including carcinoembryonic antigens in human colon adenocarcinoma: applications of Trichosanthes japonica agglutinin I for early diagnosis.

The N-linked sugar chain structures of the carcinoembryonic antigen (CEA) produced by liver metastases of colon cancers and the normal counterpart of CEA purified from human adult feces (NFA-2) were previously determined comparatively (K. Fukushima, T. Ohkura, M. Kanai, M. Kuroki, Y. Matsuoka, A. Kobata, and K. Yamashita. Glycobiology, 5:105-115, 1995). Seventy-five % of NFA-2 contained complex type sugar chains with Gal beta 1-->3GlcNAc residues, in contrast to the sugar chains of CEA, in which over 90% of the oligosaccharides contained Gal beta 1-->4GlcNAc residues, and Sia alpha 2-->6Gal beta 1-->4GlcNAc residues were detected in 18 to 65% of the oligosaccharides. The expression of Sia alpha 2-->6Gal beta 1-->4GlcNAc residues on CEA molecules in sera and tissues was investigated using Trichosanthes japonica agglutinin I (TJA-I), which interacts with Sia alpha 2-->6Gal beta 1-->4 GlcNAc residues. Ten purified CEA samples bound to a TJA-I column while seven NFA-2 samples passed through the column. Various concentrations of serum CEA samples from patients with metastatic colon cancers exclusively bound to the TJA-I column, reflecting that CEA molecules exfoliated into the blood circulation comprise sugar chains with Sia alpha 2-->6Gal beta 1-->4GlcNAc residues. In histochemical studies involving biotinylated TJA-I, normal mucosa (n = 20) and benign adenomas (n = 20) were not stained, and 83% of well and moderately differentiated colon adenocarcinomas (n = 53) reacted with TJA-I, although poorly differentiated ones (n = 9) and mucinous specimens (n = 10) were negative. Because over 90% of colon adenocarcinomas can be differentiated, TJA-I staining might be applicable to the early diagnosis of colon cancers.

Adenocarcinoma↗

Enhanced expression of type I receptors for bone morphogenetic proteins during bone formation.

Type I receptors for bone morphogenetic proteins (BMPs), i.e., BMPR-IA and BMPR-IB, are transmembrane serine/threonine kinases, that bind osteogenic protein-1 (OP-1, also termed BMP-7) and BMP-4. Using antibodies specific to BMPR-IA and -IB, we have studied the expression of BMP type I receptors in the bone formation process during embryonic development and fracture healing. In the mouse embryo, both BMPR-IA and -IB were expressed in condensing mesenchymal cells at 13.5 days post coitum (p.c.). At 15.5 days p.c., expression of BMPR-IB, but not of BMPR-IA, was observed in the cells in perichondrium of developing cartilage. At 17.5 and 19.5 days p.c., expression of both receptors was observed in chondrocytes and in osteoblasts. In normal rat adult bone, expression of BMPR-IA, but not of BMPR-IB, was observed in osteoblasts in the periosteum. Three days after the femoral fracture, expression of BMPR-IA and -IB was up-regulated in cells at the proliferating osteogenic layer of the periosteum. On day 7, both receptors were found in fibroblast-like spindle cells and chondrocytes in the endochondral ossification sites, and osteoblasts in the newly formed trabecular bone. Expression of BMPR-IA was higher than that BMPR-IB in osteogenic layer on day 3 and in osteoblasts in the trabecular bone on day 7. On day 14, expression of BMP type I receptors was observed at similar sites, albeit with lower expression levels than were observed on day 7. The present data suggest that expression of BMP type I receptors is up-regulated during bone formation, and that they may play important roles in bone morphogenesis.

Animals↗

Histopathological study on the effect of octreotide.

The present investigation was performed to clarify the mechanism of action of octreotide. On a quantitative study by electron microscopy showed that lysosomes were markedly increased in the patients receiving octreotide. Growth hormone (GH) was shown to be in the secretory granules by the postembedding immunogold technique, but no GH immunostaining was noted of the lysosomes. The present investigation suggests that retention of secretory granules and subsequent lysosomal increase are the mechanism of GH-lowering effect of octreotide.

Adenoma↗

Pituitary adenylate cyclase activating polypeptide is an extraordinarily potent intra-pancreatic regulator of insulin secretion from islet beta-cells.

Insulin secretion from pancreatic islets is controlled by peptides as well as by nutrients. We report here a novel, extraordinarily potent peptidergic regulation of insulin secretion. A 27-residue form of pituitary adenylate cyclase activating polypeptide (PACAP27) as low as 10(-14) to 10(-13) M stimulated insulin release from rat islets in a glucose-dependent manner. PACAP27 also increased cytosolic free Ca2+ concentration ([Ca2+]i) in islet beta-cells. Nitrendipine, a blocker of the L-type Ca2+ channel, abolished both [Ca2+]i and insulin responses. Vasoactive intestinal peptide, a peptide exhibiting 68% amino acid homology with PACAP, also increased [Ca2+]i in beta-cells but only at concentrations in the nanomolar range, indicating that PACAP27 is 4 logs more potent. A 38-residue form of the peptide (PACAP38) stimulated insulin release and increased beta-cell [Ca2+]i in a manner similar to that of PACAP27. PACAP-like immunoreactivity was demonstrated in pancreatic nerve fibers, islets, and capillaries. The results indicate that PACAP is a physiologically occurring peptide in pancreas and that PACAP, in a glucose-dependent manner, activates beta-cells presumably via a high affinity PACAP-selective receptor, raises [Ca2+]i by increasing the activity of L-type Ca2+ channels, and consequently stimulates insulin release. PACAP appears to be by far the most potent insulinotropic peptide known.

Animals↗

A case of epidermolysis bullosa hereditaria--dominant dystrophic type of Cockayne and Touraine.

We report a patient with the Cockayne and Touraine type epidermolysis bullosa dystrophica domains. A 6-year-old Japanese female developed blisters and erosions on the extremities 3 months after birth. Immunohistology showed a linear binding pattern of the monoclonal antibody against type VII collagen (LH:2) on the epidermal basement membrane. By means of electron microscopy and morphometric analysis, it became apparent that the anchoring fibrils were rudimentary in structure and reduced in number.

Basement Membrane↗

[Light and electron microscopic demonstration of acidic glycoconjugates by means of postembedding staining procedures using cationic colloidal gold].

The cytochemical detection of acidic glycoconjugates located in rat gastrointestinal epithelia was performed using tissue sections embedded in Lowicryl K4M and cationic colloidal gold (CCG). CCG was prepared from poly-L-lysine and colloidal gold solution (10 nm). The staining of CCG was amplified after a photochemical silver reaction using silver acetate as an ion donor at the light microscopic level. The staining solutions adjusted to pH 2.5, CCG (2.5) and pH 1.0, CCG (1.0) were used for the characterization of carboxylated and sulfated glycoconjugates. At light microscopic level, CCG (2.5) stained several cell types of mucous cells in the rat gastrointestinal tract, while CCG (1.0) stained selectively mucous cells in gastric pits, glandular pylorus, upper crypts of the proximal colon and entire crypts of the distal colon. At the electron microscopic level, both CCG (2.5) and CCG (1.0) labeled the trans side of the Golgi apparatus and mucous granules in some mucous cells. These results are consistent with previous glycoconjugates histochemistry of the rat gastrointestinal tract at both the light and electron microscopic levels. CCG (2.5) and CCG (1.0) staining methods are useful and reliable postembedding staining procedures for the light and electron microscopic demonstration of intra- and extracellular acidic glycoconjugates.

Animals↗

Cationic colloidal gold--a probe for light- and electron-microscopic characterization of acidic glycoconjugates using poly-L-lysine gold complex.

Cationic colloidal gold (CCG) was used to characterize acidic glycoconjugates in semithin and ultrathin sections of rat large intestine and salivary glands embedded in hydrophilic Lowicryl K4M resin. It was prepared from poly-L-lysine and 10 nm colloidal gold solution. The staining of CCG in semithin sections was amplified after photochemical silver reaction using silver acetate as a silver ion donor and examined under bright-field and epi-illumination microscopy. CCG adjusted to various pH levels was tested on various rat tissues whose histochemical characteristics with regard to acidic glycoconjugates are well known. At pH 2.5 CCG labelled tissues containing sialylated and sulphated acidic glycoconjugates such as the apical cell surface, mucous cells in the distal and proximal colon, and acinar cells of the sublingual gland. In contrast, CCG at pH 1.0 labelled tissues containing sulphated acidic glycoconjugates such as mucous cells in the upper crypt of the proximal colon and mucous cells in the whole crypt of the distal colon. This specificity of CCG was verified by the alteration of CCG staining following several types of cytochemical pretreatment. These results were further confirmed by electron microscopy. CCG staining is thus a useful postembedding procedure for the characterization of acidic glycoconjugates at both the light- and electron-microscopic levels.

Cations↗

Sulfated glycoconjugates demonstrated in combination with high iron diamine thiocarbohydrazide-silver proteinate and silver acetate physical development.

Sulfated glycoconjugates in epithelial cells and mesenchymal cells were investigated after staining with high iron diamine-thiocarbohydrazide-silver proteinate. One purpose of the experiment was to apply a new physical developed to the staining. Instead of silver nitrate, silver lactate or silver bromide, we used silver acetate as an ion donor. This new method allowed physical development under normal lighting conditions, and resulted in the reduction of background staining even after amplification. As the developer did not contain gum arabic, troublesome treatment was not necessary. The time required for staining was very short and the electron density of the final reaction product was high and easily identifiable under the electron microscope. Fixing was not necessary. Very small amounts of reactive substance were detectable after physical development. This developmental procedure has been applied to both the preembedding staining and postembedding staining of sulfated glycoconjugates. The results obtained using this method are presented.

Acetates↗

Subcompartment sugar residues of gastric surface mucous cells studied with labeled lectins.

We examined the intracellular localization of sugar residues of the rat gastric surface mucous cells in relation to the functional polarity of the cell organellae using preembedding method with several lectins. In the surface mucous cells, the nuclear envelope and rough endoplasmic reticulum (rER) and cis cisternae of the Golgi stacks were intensely stained with Maclura pomifera (MPA), which is specific to alpha-Gal and GalNAc residues. In the Golgi apparatus, one or two cis side cisternae were stained with MPA and Dolichos biflorus (DBA) which is specific to terminal alpha-N-acetylgalactosamine residues, while the intermediate lamellae were intensely labeled with Arachis hypogaea (PNA) which is specific to Gal beta 1,3 GalNAc. Cisternae of the trans Golgi region were also stained with MPA, Ricinus communis I (RCA I) which is specific to beta-Gal and Limax flavus (LFA) which is specific to alpha-NeuAc. Immature mucous granules which are contiguous with the trans Golgi lamellae were weakly stained with RCA I, while LFA stained both immature and mature granules. The differences between each lectin's reactivity in the rough endoplasmic reticulum, in each compartment of the Golgi lamellae and in the secretory granules suggest that there are compositional and structural differences between the glycoconjugates in the respective cell organellae, reflecting the various processes of glycosylation in the gastric surface mucous cells.

Animals↗

Cardiomyopathy, mental retardation, and autophagic vacuolar myopathy. Abnormal MRI findings in the head.

A 21-year-old man with childhood-onset mental retardation, non-obstructive hypertrophic cardiomyopathy, and vacuolar myopathy is presented. A histopathological study of biopsied skeletal muscle showed lysosomal glycogen storage mimicking acid maltase deficiency, but biochemical analysis showed normal acid alpha-glucosidase activity. Glycogenosomes were also recognized in endothelial cells on electronmicroscopic examination of biopsied skeletal muscle. Magnetic resonance imaging (MRI) findings in the head revealed the involvement of the central nervous system. This is a new type of lysosomal glycogen storage disease with multisystemic involvement. The specific biochemical defect in this disorder remains to be elucidated.

Adult↗

Subcellular localization of N-acetylglucosaminide beta 1----4 galactosyltransferase revealed by immunoelectron microscopy.

We prepared a monoclonal antibody (MAb) against N-acetylglucosaminide beta 1----4 galactosyltransferase purified from F9 embryonal carcinoma cells. The MAb recognized the protein portion of the enzyme, since it inhibited galactosyltransferase activity, reacted with the enzyme both from F9 cells and from bovine milk, and did not exhibit anti-carbohydrate activity. Using this MAb, we studied the subcellular localization of the enzyme by immunoelectron microscopy. Intense staining was observed in trans-Golgi stacks within testicular interstitial cells and mucous neck cells, confirming the specificity of the immunological reaction. Cell surface galactosyltransferase was detected in the following regions: cultured cells such as F9 embryonal carcinoma cells, testicular interstitial cells, seminiferous tubule epithelial cells, Sertoli cells, the head of the epididymal sperm, epididymal epithelial cells, and apical surfaces of epithelial cells in the fundic gland and of intestinal goblet cells. The use of Triton X-100 intensified the cell surface immunoreactivity, and in certain cases the mode of distribution of the cell surface enzyme was different from that described in previous reports. In addition, nuclear envelopes of cultured cells were distinctly stained. The possible significance of the latter finding is discussed in relation to recent advances in nuclear localization of glycoproteins.

Animals↗

A retinoic acid responsive gene MK found in the teratocarcinoma system is expressed in spatially and temporally controlled manner during mouse embryogenesis.

A newly identified gene MK is transiently expressed in early stages of retinoic acid-induced differentiation of embryonal carcinoma cells (Kadomatsu, K., M. Tomomura, and T. Muramatsu, 1988. Biochem. Biophys. Res. Commun. 151:1312-1318). MK gene has been predicted to code a polypeptide that is rich in basic amino acids and cysteine and is not related to any other peptides so far reported. In the present study, we investigated MK expression during mouse embryogenesis by in situ hybridization. The MK transcript was detected all over the embryo proper of the 7-d embryo, while it was not detectable in the 5-d embryo. The ubiquitous expression continued in the 9-d embryo proper. On the 11th-13th d of gestation, the sites where MK gene was intensely expressed became progressively restricted; these sites were the brain ectoderm around the lens and brain ventricles, the anterior lobe of the pituitary gland, the upper and lower jaw, the caudal sclerotomic half of vertebral column, the limbs, the stomach, and the epithelial tissues of the lung, the pancreas, the small intestine, and the metanephros. These areas include the region where secondary embryonic induction is prominent. In the 15-d embryo, only the kidney expressed MK significantly. These data suggest that MK gene plays a fundamental role in the differentiation of a wide variety of cells; MK gene may also play some specific roles in generation of epithelial tissues, and remodeling of mesoderm.

Animals↗

Ultrastructural immunocytochemical studies of blood group substances in human eccrine glands.

We investigated the ultrastructure of blood group antigens A, B, and H in human eccrine glands by means of the immunogold labeling technique. Blood group antigens A, B, and H were found in the Golgi apparatus, secretory granules, and over the apical and basolateral cell membranes of dark cells of eccrine glands depending on the blood group phenotype of the donors. Both A and B antigens were found in the dark cells of AB donors. The labeling pattern of the Golgi stacks seemed to have a polarity whereby the anti-blood group A antibody labeled all the stacks, whereas anti-blood groups B and H bound to the trans side of the Golgi complex. These observations suggest that the blood group substances are secreted into the lumen after being processed through the Golgi apparatus and the immature and mature granules in the dark cells of human eccrine glands.

ABO Blood-Group System↗