Biomedical subjects

S Furuya

Publications and source records attributed to S Furuya.

At least 109 records · Page 6Linked to original sources

PubMed1992

Purification and localization of a calcium-binding protein in human spermatozoa.

The purpose of this study was to purify a calcium-binding protein (CalBP) from human spermatozoa of 226 men and to determine the localization of this protein in spermatozoa. The sperm cells were extracted with 0.6 M KCl, and the KCl extract was then subjected to gel filtration and high performance liquid chromatography. Two CalBPs of Mr = 38 kDa and 52 kDa were found by 45Ca(2+)-binding on blotted proteins. Only a 52 kDa CalBP (CalBP-52) was purified to a final yield of 0.007%. The isoelectric point of this protein was 5.1. The human CalBP-52 reacted with rabbit antiserum directed against rat 52 kDa CalBP. An immunocytochemical study showed that this protein was localized on the sperm head. It is postulated that this protein may have important functions related to Ca(2+)-transport into sperm cells.

Animals↗

PubMed1992

Characterization of adrenodoxin precursor expressed in Escherichia coli.

The precursor of bovine adrenodoxin (pAd), a mitochondrial protein, was expressed in Escherichia coli. The cloned cDNA of pAd was ligated to an expression vector pET-3d, and silent mutations were introduced into the N-terminal portion of the cDNA in order to increase the expression. The precursor was highly expressed (approximately 20% of the total cell protein) as the inclusion body, and contained an iron-sulfur center as judged from its optical absorption spectra. The inclusion body was solubilized with 7 M urea and pAd was purified in the presence of urea. The purified pAd was efficiently imported into isolated bovine adrenal cortex mitochondria and processed to the mature form. The import reaction required ATP inside the mitochondria in addition to the inner membrane potential, and was strongly inhibited by trypsin treatment of the mitochondria, as in the case of the in vitro translated precursor. It was, however, not dependent on the unfolding activity of the cytosolic factor with extramitochondrial ATP.

Adenosine Triphosphate↗

PubMed1992

Detection of Epstein-Barr virus DNA in a Japanese case of lymphoepithelioma-like thymic carcinoma.

Epstein-Barr virus DNA was detected in a case of lymphoepithelioma-like thymic carcinoma. A homogeneous terminal structure of the viral DNA was demonstrated in this case, indicating the presence of the viral genome in clonally expanded tumor cells. Since all of 26 other thymic epithelial tumors (eight non-invasive, 13 invasive thymomas and four non-lymphoepithelioma-like thymic carcinomas) in Japanese were negative by polymerase chain reaction, it is suggested that lymphoepithelioma-like thymic carcinoma may represent a unique pathological entity distinct from Epstein-Barr virus-negative thymic epithelial tumors, which are in the majority in Japan.

Carcinoma, Squamous Cell↗

PubMed1992

Immunohistochemical study of c-erbB-2 oncoprotein overexpression in human major salivary gland carcinoma: an indicator of aggressiveness.

In order to analyze the correlation between immunohistochemical positivity for c-erbB-2 oncoprotein and prognosis in patients with malignant salivary gland tumors, 59 cases of malignant tumors of the major salivary glands, including 35 parotid gland, 20 submaxillary gland and 4 sublingual gland tumors, were studied immunohistochemically using a polyclonal antibody against c-erbB-2 oncoprotein. Positive staining was observed in 13 (22%) of the 59 cases. Interestingly, positive results were obtained only in adenocarcinoma (6/20) and carcinoma in pleomorphic adenoma (7/15), and not in any other histological types such as adenoid cystic carcinoma, mucoepidermoid tumor, and squamous cell carcinoma. There was no correlation between the degree of differentiation of adenocarcinoma and c-erbB-2 positivity. Since the carcinoma in pleomorphic adenoma positive for c-erbB-2 oncoprotein was adenocarcinoma, adenocarcinoma and adenocarcinoma in pleomorphic adenoma were placed together (n = 33), and the presence or absence of c-erbB-2 oncoprotein in this group was examined for correlation with patients' survival and other clinicopathological features, including clinical stage, tumor size, surgical margins, and lymph node status. The c-erbB-2-positive tumors tended to be more advanced and larger than negative tumors. Similarly, c-erbB-2-positive tumors were difficult to resect completely, were associated with lymph node metastasis more frequently, and showed lower disease-free survival than negative cases (P less than .05). We conclude that immunohistochemical positivity for c-erbB-2 is an indicator of aggressiveness in both adenocarcinoma and adenocarcinoma in pleomorphic adenoma of the major salivary glands.

Adenocarcinoma↗

PubMed1992

The AMeX method: a multipurpose tissue-processing and paraffin-embedding method. Extraction of protein and application to immunoblotting.

The authors have previously reported a new fixation and paraffin-embedding method (the AMeX method), which preserves many antigens as well as high molecular-weight DNA and RNA that are normally destroyed by the routine formalin fixation and paraffin-embedding process. In the present study, the authors analyzed the preservation of protein suitable for sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and immunoblotting in tissue fixed by the AMeX method. The method used for extraction of protein from AMeX-processed tissue sections after deparaffinization was the same as that for extraction from fresh tissues. The total amount of protein extracted from 50-mg (wet weight) AMeX-processed mouse liver tissue was the same as that from fresh tissue. The electrophoretic mobility and staining intensity of protein on SDS-polyacrylamide gel, and the immunoblotting pattern and staining intensity with several antibodies, were identical for both AMeX-processed and fresh tissue. Degradation of protein was minimal for storage periods of 2 years in paraffin block. The authors also showed that pellets of cultured cells can be processed by this method for immunologic analysis. This new fixation and paraffin-embedding method is a useful tool for obtaining information on correlations between morphologic features and immunochemical and molecular biological data.

Animals↗

PubMed1992

[Relationship between juxtapapillary duodenal diverticula and biliopancreatic disease--evaluation by endoscopic biliary manometry].

Endoscopic biliary manometry was performed to evaluate the motor activity of the sphincter of Oddi (SO) in 28 patients, 13 with juxtapapillary duodenal diverticula (8 with biliopancreatic disease) and 15 without diverticula (10 with biliopancreatic disease). So pressure and the rate of irregular wave pattern of phasic contraction in patients with diverticula were significantly higher than those in patients without diverticula. Especially all the patients with both diverticula and biliary stones had motor disorders of the SO. The patients with diverticula were also divided into three groups by endoscopic findings for the location of diverticular; The papilla of Vater was located close to diverticula (within about 4 cm) in group A, on the edge of diverticula in group B, in the diverticula in group C. Diverticula could have more direct effect on the motor activity of the SO in group C. Those results suggest juxtapapillary diverticula have close relationship with the motor activity of the SO and biliopancreatic disease, especially in cases which the papilla of Vater located in the diverticula. We conclude that the motor disorders of the SO might be responsible for biliopancreatic disease in patients with juxtapapillary diverticula.

Ampulla of Vater↗

PubMed1991

Establishment of photoreceptor cell polarity in culture revealed by mushroom lectin binding.

Differentiation of photoreceptor cells dissociated from chick embryo was investigated in a monolayer culture at low cell density and low serum concentration. The precursor cells were initially round and finally adopted the elongated and monopolar shape characteristic of such photoreceptor cells in vivo. They exhibited the primitive inner segment, and on its distal side showed a crest-like membrane expansion instead of the developed outer segment. The cell polarity of these cultured photoreceptor cells was examined using mushroom lectin, which has specific affinity for the D-galactose-beta(1,3)-N-acetylgalactosamine moiety. Rhodamine-labeled mushroom lectin uniformly initially stained the surface of early round photoreceptor cells, but with time the staining became restricted to the inner segment and its distal membrane expansion in all elongated photoreceptor cells at 12 days from the beginning of development. In semithin sections of 12-day-old chick embryo retina, mushroom lectin also stained the immature inner segment that had emerged at this stage. After hatching, light and electron microscopic observations revealed that the entire scleral surface of retinal plasma membranes as far as the outer limiting membrane, i.e. the inner and outer segments of all types of photoreceptor cells and also Müller cell processes, were stained with the mushroom lectin. These results clearly show that all photoreceptor cells can establish their inherent cell polarity even in culture, and that mushroom lectin is a valuable marker, for the investigation of photoreceptor cell polarity.

Animals↗

PubMed1991

[The clinical application of multi-voxel 1H-CSI (chemical shift imaging) in brain tumors].

The 1H-Chemical shift imaging (CSI) method was developed and applied to reveal the metabolic changes in brain tumors. In the tumor, the decrease of NAA and the increase of lactate were observed by the CSI. These changes were more remarkable in the malignant tumors than in the benign tumors. The lactate was also observed in the tissue surrounding the tumors, which was supposed to be produced in the brain with hypoperfusion condition or to be leaked out from the tumor. The 1H-CSI has an advantage to demonstrate the pathophysiological changes in a wide area of the brain.

Aspartic Acid↗

PubMed1991

[Detection of A-P shunt by MR angiography].

Magnetic Resonance Angiography using a time-of-flight method was performed on two cases with arterial-portal shunting (A-P shunt). Each case was examined both with and without presaturation applied above the diaphragms. Signal intensity in the portal vein on these cases decreased with presaturation. This presaturation normally eliminates signal from inflowing spins in the artery but never effect on that in portal vein. Therefore the decrease of signal intensity in the portal vein with presaturation indicates the arterial inflow to the portal vein.

Arteriovenous Fistula↗

PubMed1991

Analysis of two-dimensional electrophoretic patterns of proteins obtained from the sera of normal and tumor-bearing nude rats.

To classify two-dimensional electrophoresis (2-DE) patterns of normal and abnormal samples, a new parameter, named shift value, is introduced. The shift value is defined by the product of three indices; differences in density, differences in area, and the Euclid distance between peaks of matched glycoprotein spots in the 2-DE patterns. Shift values obtained from the differences between the 2-DE patterns of tumor-bearing and normal sera (control) were always found to be larger than those obtained from two control patterns. The shift value obtained from glycoprotein spots could be more effectively used to distinguish normal and abnormal patterns than that obtained from simple proteins. In our earlier attempts to compare serum proteins of normal and tumor patients, we could not discriminate differences caused by genetic background. In order to circumvent this difficulty, we employed an inbred strain of nude rats into which various types of human cancer had been implanted. Reliability of the analysis is enhanced by using a polyacrylamide gel backed with a silanized glass support and an automatic 2-DE apparatus.

Animals↗

PubMed1991

Cytosolic and mitochondrial surface factor-independent import of a synthetic peptide into mitochondria.

We chemically synthesized a peptide, 11 beta-45, which was composed of 45 amino acid residues including the whole extension peptide and some of the mature portion of bovine cytochrome P-450(11 beta) precursor. 11 beta-45 was imported into mitochondria in vitro depending on the mitochondrial membrane potential, but its import did not require extramitochondrial ATP. Although cytosolic protein factors in the high speed supernatant of reticulocyte lysate are known to stimulate the import of various precursor proteins into mitochondria, the import of 11 beta-45 was not stimulated by cytosolic factors in reticulocyte lysate. The import of the peptide did not require mitochondrial surface protein components because its import was not affected by trypsin treatment of mitochondria. On the other hand, trypsin treatment of mitoplasts resulted in a great reduction in the import of the peptide, indicating that 11 beta-45 interacts during the import process with some protein components located inside mitochondria. These observations indicated that the peptide 11 beta-45 was imported via the potential-dependent pathway as in the case of precursor proteins, but skipped the interactions with cytosolic factors and mitochondrial surface components normally required for the import of precursor proteins.

Adenosine Triphosphate↗

PubMed1991

The AMeX method: a multipurpose tissue-processing and paraffin-embedding method. III. Extraction and purification of RNA and application to slot-blot hybridization analysis.

RNA was extracted from tissues processed by a new fixation and paraffin-embedding method (the AMeX method) and examined by Northern blot analysis and slot-blot analysis. The RNA extraction method for AMeX-processed tissue sections after the deparaffinization step was the same as that for fresh materials. The total amount of cellular RNA extracted from AMeX-processed mouse liver tissue was slightly less than that extracted from fresh tissue. In tissues of malignant lymphoma, the total amount of cellular RNA extracted from 25 sections each 20 microns thick was about 1.6-1.8 micrograms/mm2, regardless of the histological subtype and period of storage. The extracted RNA was moderately degraded, and usually could not be used for Northern blot hybridization analysis. The intensity of ethidium bromide staining and the hybridization signals of RNA extracted from AMeX-processed tissues were usually reduced in comparison with RNA from fresh material, but specific signals could be detected by slot-blot hybridization analysis. We have demonstrated previously that the AMeX method preserves high-molecular-weight DNA and various antigens. Since the present study showed that information on mRNA can be obtained from AMeX-processed tissue, the versatility and usefulness of this method were further proven.

Animals↗

PubMed1991

Localization of [125I]endothelin-1 in rat tissues observed by electron-microscopic radioautography.

[125I]Endothelin-1 (ET-1) was administered intravenously into rats, and binding sites in various tissues were examined by electron-microscopic radioautography. Labeling was observed predominantly on the glomerular fenestrated endothelial cells of kidney, alveolar capillary endothelial cells of lung, fat-storing cells in the sinusoids of liver, and subepithelial myofibroblasts of the small intestine. At first, silver grains were observed mostly on the plasmalemma of these cells and with time translocated into the cytoplasm of these cells. Myofibroblasts of the small intestine were cultured to study the cellular effects of ET. By fura-2 fluorescence method, transient increase and oscillation of intracellular Ca2+ level were observed in the cultured myofibroblasts following the application of ET-1 or endothelin-3 (ET-3). These results suggest that ET induces diverse physiological reactions in specific cells of various tissues.

Animals↗

PubMed1991

Detection of Epstein-Barr virus DNA in formalin-fixed paraffin-embedded tissue of nasopharyngeal carcinoma using polymerase chain reaction and in situ hybridization.

The polymerase chain reaction method for amplification of DNA in formalin-fixed, paraffin-embedded tissue sections was used to detect Epstein-Barr virus DNA in nasopharyngeal carcinomas from Japanese patients. Thirty-one cases of nasopharyngeal carcinoma and 8 cases of lymph node metastasis of nasopharyngeal carcinoma were studied. Detection rates of Epstein-Barr virus in various types of nasopharyngeal carcinoma according to the World Health Organization classification were as follows: 10 of 10 undifferentiated carcinomas, 8 of 13 nonkeratinizing carcinomas, and 5 of 7 keratinizing carcinomas. Eight lymph node metastases, for which the primary was positive for Epstein-Barr virus, also contained Epstein-Barr virus DNA. By in situ hybridization using a biotinylated Epstein-Barr virus probe, it was clearly demonstrated that Epstein-Barr virus DNA was localized in the nuclei of the neoplastic cells. The clinical features of nasopharyngeal carcinoma with or without Epstein-Barr virus were not different. These results demonstrate that nasopharyngeal carcinoma in Japanese patients is closely associated with Epstein-Barr virus infection, similar to nasopharyngeal carcinoma of other endemic and nonendemic areas.

Carcinoma↗

PubMed1991

[Endoscopic manometry of common bile duct and the sphincter of Oddi in patients with biliary tract stones and in controls].

Endoscopic manometry using microtransducer was applied to evaluate the motor activity of the sphincter of Oddi (SO) and common bile duct (CBD) in patients with biliary tract stones and in controls. CBD pressure, SO pressure and the incidence of irregular phasic wave pattern (IRPWP) were relatively higher in patients with biliary tract stones than those in controls. There was no significant difference in CBD and SO pressure between patients with dilated CBD and patients with non-dilated CBD, however the incidence of IRPWP was significant higher in patients with dilated CBD than that in patients with non-dilated CBD. SO pressure and the incidence of IRPWP were significant higher in patients with papillitis than those in patients without it. Patients with valvular orifice of the papilla of Vater showed high incidence of IRPWP, and in such cases it was suggested that SO had different motor functions for CBD and pancreatic duct because these ducts were seen opening onto the papilla separately according to the findings of pancreatocholangiogram. We concluded that endoscopic manometry of CBD and the SO was useful to evaluate the motor activity of SO and provided a basis for the assessment of the motor function mechanism of SO. Our results indicated the motor activity of SO had close relationship with biliary tract stones, CBD dilatation and endoscopic findings of the papilla of Vater.

Adult↗

PubMed1990

Ultrastructure and formation of diaphragmed fenestrae in cultured endothelial cells of bovine adrenal medulla.

The ultrastructure of diaphragmed fenestrae and the process of their de novo formation were examined in cultured endothelial cells cloned from fenestrated capillaries of bovine adrenal medulla. One clone frequently formed many diaphragmed fenestrae in highly attenuated regions of endothelium during 1-1.5 months of culture on reconstituted collagen gel. Stereo views of thick sections showed round or oval clusters of geometrically arranged fenestrae, each with a central knob. The number of diaphragmed fenestra per cluster was 50 +/- 13/microns 2. The inner diameter of the fenestrae was 50-60 nm. In the cells having small clusters of fenestrae, plasmalemmal vesicles, each having a thin diaphragm with a central knob, were accumulated (56 +/- 18/microns 2) and arranged geometrically, mostly on the basal plasmalemma. At the border between the cytoplasm and the cluster of fenestrae, plasmalemmal vesicles of the basal plasmalemma fused with the opposing apical plasmalemma. A model for the process of fenestrae formation in vitro is proposed.

Adrenal Medulla↗

PubMed1990

Morphological behavior of cultured bovine adrenal medulla capillary endothelial cells.

Bovine adrenal medulla capillary endothelial cells were isolated and cloned, and their morphological behaviors in vitro were examined. In the culture of primary or early passage, one type of colony formed intracellular lumina both on the dish and in the three dimensional collagen gel. Another type proliferated well and showed morphology ranging from slender-shape to cobblestone shape, and were easily cloned. Cloned cells which showed slender-shapes formed tubular network on plastic dish after addition of PMA, OAG or vanadate, and these cells also formed multicellular tubules in the three dimensional collagen gel. However, the formation of diaphragmed fenestrae by these slender-shape clones was rare. One clone which showed cobblestone shape formed diaphragmed fenestrae, when cultured on collagen gel for more than one month. Isolated colonies or clones showed heterogeneity of cell shape, angiogenic behaviors and fenestrae formation.

Adrenal Medulla↗

PubMed1990

Cholinergic synapse formation between NG108-15 and muscle cells and modulation of transmission.

Mouse neuroblastoma x rat glioma hybrid NG108-15 cells form cholinergic synapses with rat or mouse muscle cells in culture. The rate of synapse formation is greatly dependent on intracellular cyclic AMP concentrations. The synapse formation is lower in the presence of glia maturation factor, a partially purified brain extract. Once the synapse between NG108-15 cells and myotubes has been formed, this synapse is stable for days. Extracellular application of serotonin, PGF2 alpha, PGD2, neurotensin and bradykinin on NG108-15 cells increases synaptic transmission. Since bradykinin increases the level of intracellular inositol 1,4,5-trisphosphate (InsP3), bradykinin-induced facilitation is due to InsP3-dependent elevation of intracellular Ca concentrations.

Animals↗