Search PubMed⌕ Search

Biomedical subjects

H Sugihara

Publications and source records attributed to H Sugihara.

At least 55 records · Page 3Linked to original sources

Characterization of coagulase from Staphylococcus intermedius.

A protein coagulase was isolated from Staphylococcus intermedius 6131 using bovine prothrombin-Sepharose 4B and Bio-gel P-4 column chromatographies. Homogeneity was demonstrated by the formation of a single band in polyacrylamide gel electrophoresis and isoelectric focusing. The purified preparation possesses a molecular weight of 64,500, an isoelectric point of 4.1, consists of 615 total amino acid residues and demonstrates coagulase activity for human and rabbit fibrinogen, but does not show the activity for rat or guinea pig fibrinogens. This purified protein contains galactose and fucose, and the amino-terminal amino acid sequence was determined. The coagulase activity is inhibited by N-bromosuccinimide (NBS), suggesting that tryptophan is involved in this activity. The coagulase was heat stable to 80 degrees C and stable to pH over the range of 7-9. This is the first report of coagulase from Staphylococcus intermedius.

Animals↗

[Assessment of myocardial damage and metabolic disorder in the left ventricle in patients with mitral stenosis using 201Tl and 123I-BMIPP myocardial SPECT].

This study was designed to evaluate the myocardial damage and metabolic disorder of the left ventricle in patients with mitral stenosis. We studied 15 patients with mitral stenosis. Their grade of chronic heart failure using New York Heart Association classification were class I: 5 patients, class II: 5, class III: 3, class IV: 2, respectively. The severely stenotic group (valve area < 1.5 cm2) included 6 patients, mildly stenotic group (1.5 cm2 < or = valve area < 2.5 cm2) included 9. A 111 MBq of 123I-BMIPP was intravenously injected at rest, SPECT images were obtained at 15 min and 3 hours after injection. A 111 MBq of 201Tl was intravenously injected at rest, and SPECT images were obtained at 15 min after injection. Washout rate (WR) of 123I-BMIPP from the whole left ventricle was obtained using polar maps. The concentration of norepinephrine (NE: pg/ml) in the blood at rest was measured. The mean values of pulmonary artery pressure was measured in ten patients using Swan-Ganz catheter. 123I-BMIPP myocardial SPECT and measurement of NE were reexamined in 5 patients after mitral valvuloplasty. NE values were 476 +/- 72 and 793 +/- 286 in classes I + II and III + IV, respectively. NE values was increased in the severe heart failure group (p < 0.05). NE values were 480 +/- 69 and 743 +/- 295 in the mildly and severely stenotic groups, respectively. NE value was increased in severely stenotic group (p < 0.05). Twelve patients showed normal uptake on both 201Tl and 123I-BMIPP myocardial SPECT. Three patients showed slightly reduced uptake on both 201Tl and 123I-BMIPP myocardial SPECT. WR was 27.2 +/- 4.8% and 44.3 +/- 6.7% in class I + II and class III + IV, respectively. WR was increased in severe heart failure group (p < 0.05). WR was 27.8 +/- 6.0% and 41.3 +/- 9.4% in the mildly and severely stenotic group, respectively. WR was increased in the severely stenotic group (p < 0.05). NE was correlated with WR (p < 0.001). In patients with mitral valvuloplasty, WR was 44.3 +/- 6.7% and 31.4 +/- 4.7% before and after mitral valvuloplasty, respectively. NE values were 857 +/- 266 and 574 +/- 165, respectively. Both WR and NE were decreased after mitral valvuloplasty (p < 0.01). In patients with mitral stenosis, WR was increased in the severe heart failure group and severely stenotic group without apparent myocardial damage. Myocardial metabolism in the left ventricle might be influenced by right heart failure through, for example, NE and neurohormonal factors.

Aged↗

[Assessment of myocardial fatty acid metabolism in patients with angina pectoris and diabetes mellitus using 123I-BMIPP myocardial scintigraphy].

PURPOSE: We studied the effect of myocardial ischemia and diabetes mellitus (DM) on the myocardial fatty acid metabolism using 123I-BMIPP myocardial scintigraphy. METHODS: We performed 123I-BMIPP myocardial scintigraphy in 50 patients with myocardial ischemia and without DM (AP), in 30 patients with myocardial ischemia and DM (AP + DM), 12 patients with DM and without myocardial ischemia (DM), and in 10 normal subjects (N). Myocardial uptake rate of 123I-BMIPP was obtained using the time activity curve. Myocardial washout rate of 123I-BMIPP was calculated using the polar images of early and delayed SPECT images. RESULTS: Myocardial uptake rate of 123I-BMIPP (%) were AP: 4.9 +/- 0.6, AP + DM: 5.5 +/- 0.5, DM 5.7 +/- 0.5 and N: 5.0 +/- 0.4. 123I-BMIPP myocardial uptake rate was increased in AP + DM and DM. 123I-BMIPP myocardial washout rate (%) were AP: 30.2 +/- 4.3, AP + DM: 24.5 +/- 3.9, DM: 16.1 +/- 2.8 and N: 19.4 +/- 3.2. 123I-BMIPP myocardial washout rate was increased in AP and AP + DM. 123I-BMIPP myocardial washout rate was increased particularly in patients with multi-vessels disease. 123I-BMIPP myocardial washout rate was decreased in DM. CONCLUSION: The present study suggested that diabetes mellitus increased myocardial fatty acid uptake and decreased myocardial fatty acid washout, and that myocardial ischemia increased myocardial fatty acid washout.

Aged↗

Involvement of nitric oxide in phencyclidine-induced place aversion and preference in mice.

The present study investigated the involvement of nitric oxide (NO) in phencyclidine (PCP)-induced place aversion and preference in the place conditioning paradigm. PCP-induced place aversion in naive mice was dose-dependently attenuated by administration of N(G)-nitro-L-arginine methyl ester (L-NAME), a NO synthase (NOS) inhibitor, during the conditioning. The NOS activity and dopamine (DA) turnover in the hippocampus in mice showing PCP-induced place aversion were decreased, such changes being restored by administration of L-NAME during the conditioning. On the other hand, PCP-induced place preference in mice pretreated with PCP for 28 days was not attenuated by administration of L-NAME during the conditioning. Although NOS activity was not changed, the DA turnover in the cerebral cortex was increased in mice showing PCP-induced place preference. In mice pretreated with L-NAME and PCP for 28 days before the place conditioning paradigm, PCP neither induced place preference, nor changed the NOS activity or DA turnover. These results suggest that NO is involved in the acquisition of PCP-induced aversive effects, and in the development of PCP-induced preferred effects. Further, the functional change of the DAergic neuronal system mediated by NO in the hippocampus and cerebral cortex may be necessary for the expression of aversive effects and development of preferred effects, respectively, induced by PCP.

Animals↗

C11orf21, a novel gene within the Beckwith-Wiedemann syndrome region in human chromosome 11p15.5.

A novel gene, C11orf2, was identified by BLAST search in the human chromosome 11p15.5 region potentially responsible for Beckwith-Wiedemann Syndrome (BWS) and some cancers. Two cDNA clones with different sizes were obtained, which share a potential ORF of 399bp and are different in their 3' untranslated regions. This gene was revealed to be expressed exclusively in human heart and in almost no other tissues examined by northern blotting. Two transcripts of different sizes, 0.9 and 3.1kb, were identified in heart, consistent with the length of the two cDNA clones. The gene shows biallelic expression (non-imprinted) in fetal liver, although it is located in the imprinted domain of 11p15.5. C11orf21 codes a protein of 132 amino acids as proved by the expression of C11orf21-EGFP fusion protein in cultured cells. The EGFP-fusion protein expressed in cultured cells localized mainly in the cytoplasm.

Alleles↗

Primary structure and functional characterization of bilitoxin-1, a novel dimeric P-II snake venom metalloproteinase from Agkistrodon bilineatus venom.

The amino acid sequence of the hemorrhagic toxin, bilitoxin-1, isolated from the venom of Agkistrodon bilineatus was determined by the Edman sequencing procedure of peptides derived from digests utilizing cyanogen bromide, clostripain, lysyl endopeptidase, and Staphylococcus aureus V8 protease. A molecular mass of 80,000 Da was observed in the nonreduced state and 48,000 Da was observed in the reduced state, as demonstrated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Each subunit consists of 291 amino acid residues and has a calculated molecular mass of 32,276 Da. The toxin contains fucose, galactosamine, glucosamine, galactose, mannose, and N-acetylneuraminic acid and three N-linked glycosylation consensus sites. Hydrazinolysis and ESI mass spectrometry revealed that asparagine was the carboxyl-terminal amino acid. The disintegrin-like domain of bilitoxin-1 lacks the RGD cell-binding sequence, which is substituted by the MGD sequence. Under certain conditions, the disintegrin domain is autoproteolytically processed from the native protein. Studies with the bilitoxin disintegrin demonstrated that it lacks platelet aggregation inhibitory activity, probably reflecting the substitution of RGD by MGD. The hemorrhagic activity of the asialobilitoxin-1 was only 25% of bilitoxin-1, while proteolytic activity was unaffected. The three-dimensional structure of this toxin was modeled and was shown to likely possess a structure similar to that of adamalysin II (Gomis-Rüth et al., EMBO J. 12, 151-157 (1993)) and the disintegrin kistrin (Adler et al., Biochemistry 32, 282-289 (1993)). In summary, here we report the first primary structure of a dimeric, P-II snake venom metalloproteinase and the biological role of bilitoxin-1 glycosylation and the disintegrin domain.

Agkistrodon↗

An air-liquid interface promotes the differentiation of gastric surface mucous cells (GSM06) in culture.

The gastric surface epithelium is situated at an air-liquid interface because the luminal surface of the alimentary tract is in continuity with the air phase. However, the effects of this microenvironment on the gastric epithelium remain unclear. The aim of this study was to clarify the effects of an air-liquid interface on gastric epithelial cell biology. Gastric surface mucous cells (GSM06) were cultured at an air-liquid interface. Cultured cells were examined by histology, histochemistry, and transmission electron microscopy. When the cells were cultured at an air-liquid interface, the surface cells on the collagen gel became tall columnar and secreted periodic acid-Shiff-positive substances at the apical surface. These cells indicated many mucous granules in the apical cytoplasm and organized the basal lamina at the contact side with the gel. In contrast, under immersed condition, the surface cells showed immature features. This is the first report of an air-liquid interface promoting the differentiation of gastric surface mucous cells in a reconstruction culture of the gastric surface epithelial layer, suggesting that an air-liquid interface may function as a crucial luminal factor to maintain the homeostasis of gastric mucosa.

Air↗

Air exposure promotes fibroblast growth with increased expression of mitogen-activated protein kinase cascade.

Subepithelial tissue cell types in vivo are separated from air by the surface-covering epithelial layer of various organs, e.g., the skin, cornea, and respiratory and upper alimentary tracts. The epithelial defect caused by inflammatory, traumatic or surgical injury would be expected to expose the subepithelial tissue-localized fibroblasts to influx air. However, it is unclear what effects air stimulation elicits in fibroblast growth, which is critical for wound healing. To address this question, we examined the proliferation of 3T3 fibroblasts with bromodeoxyuridine (BrdU) uptake, using fibroblast-embedded collagen gel culture with or without air exposure. The BrdU intake of air-exposed fibroblasts was about 6 times that of air-nonexposed cells. To further characterize this fibroblast growth, we examined the expression of mitogen-activated protein kinase (MAPK) cascade, which plays a key role in the growth-signaling pathway of various cell types. Immunohistochemistry and Western blotting showed that air exposure increased MAPK cascade expression of the cells more strongly than air nonexposure. The data indicate that air exposure promotes MAPK cascade-associated fibroblast growth, suggesting in turn that in wound repair air stimulation itself may be involved in the basic mechanisms of subepithelial fibroblast proliferation and that it may be related to the pathogenesis of excessive fibroplasia through fibroblast overgrowth.

3T3 Cells↗

Sequential numerical changes of chromosomes 7 and 18 in diffuse-type stomach cancer cell lines: combined comparative genomic hybridization, fluorescence in situ hybridization, and ploidy analyses.

Sequential changes of chromosomal copy number were analyzed retrospectively in five diffuse-type gastric cancer cell lines by comparative genomic hybridization (CGH), DNA cytometry, and fluorescence in situ hybridization (FISH) with centromeric and painting probes. By CGH, we found loss of 18q21 in all of the cell lines and gains of 7p11-q31, 20q, and 22 in four of the five cell lines. Actual copy numbers of chromosomes 7 and 18 were determined by FISH: disomy 18 with (partial) loss of 18q in the two DNA-diploid cell lines (AGS and MKN-45), trisomy 7 in MKN-45, disomy 18 and tetrasomy 7 with one-copy loss of 7p and one-copy gain of 7q tip in DNA-triploid HSC-39/40A, and trisomy 18 and hexasomy 7 with one-copy loss of 7q in DNA-tetraploid KATO-III. Because the DNA aneuploidy is thought to result through tetraploidization, and the duplicated chromosomal changes in DNA aneuploid tumors seem to precede tetraploidization, the duplicated gain of chromosome 7 and one-copy loss of 7q in KATO-III were inferred to have occurred before and after tetraploidization, respectively. Similarly, HSC-39/40A were inferred to be preceded by the DNA-diploid stage with disomy 7 and monosomy 18. As the loss of 18q21 and the gain of 7p11-q31 were inferred to have occurred already in the DNA diploid stage in at least four and two of the cell lines, respectively, the 18q21 loss may be more important than the 7q gain as an earlier event in the genesis of diffuse-type stomach cancer. The combined CGH, FISH, and ploidy analyses thus give us a clue to extract important earlier events from the chromosomal changes that were screened by CGH alone.

Adenocarcinoma↗

Uncommon and dynamic changes detected by 123I-15-(p-iodophenyl)-3-R,S-methylpentadecanoic acid myocardial single photon emission computed tomography in a stunned myocardium induced by coronary microvascular spasm.

A 55-yr-old man underwent surgery. Soon after the procedure was finished, the patient complained of chest pain, and the electrocardiogram showed increase in the ST-segment in some leads. Emergency angiography showed normal coronary arteries, but there was asynergy in the left ventricle, and delayed filling of contrast medium was observed in the LCA. An intracoronary infusion of isosorbide dinitrate did not improve the delayed filling of contrast medium or ST segment increase in the electrocardiogram. Soon after nicorandil was injected into the LCA, the patient's symptoms, electrocardiogram, and delayed filling of contrast medium dramatically improved. On the second day, initial imaging by 123I-BMIPP myocardial SPECT showed a moderate increase in tracer uptake in the apico-anteroseptal region and a moderate decrease in tracer uptake in the lateral region, in which the first left ventriculography showed akinesis, and delayed imaging revealed a moderate increase in tracer uptake in the apical region and a high washout of 123I-BMIPP in the anteroseptal and lateral regions. On the sixth day, initial imaging by 123I-BMIPP myocardial SPECT showed a moderate decrease in tracer uptake in the apical and lateral regions and a mild decrease in tracer uptake in the anteroseptal region, and delayed imaging revealed a moderate increase in tracer uptake in the apical region and a high washout of 123I-BMIPP in the anteroseptal and lateral regions. By the 30th day, 123I-BMIPP myocardial SPECT had normalized. We consider that these dynamic changes in 123I-BMIPP myocardial SPECT imaging may reflect metabolic changes in fatty acids in the ischemic state, the size of the triacylglycerol pool, and the degree of turnover in the triacylglycerol pool.

Coronary Vasospasm↗

Ischemic hepatitis induced by mesenteric volvulus in a patient with chronic obstructive lung disease.

A 66-year-old man with chronic obstructive lung disease was admitted to our hospital, presenting with mesenteric volvulus and mild liver injury. A superior mesenteric angiogram revealed that the arteries supplying the small intestine were twisted in the arterial phase, while the portal vein was not visualized in the late phase. A celiac angiogram demonstrated that portal blood flow from the splenic venous return was maintained. The patient's symptoms had almost resolved the day after admission, and his serum transaminases level had gradually decreased to normal with conservative therapy. A superior mesenteric angiogram on the 13th hospital day showed a normal arteriogram and the portal vein demonstrated blood flow from the superior mesenteric vein. Liver biopsy revealed hemorrhagic necrosis around the central veins, which was compatible with ischemic hepatitis. Since the patient's O2 saturation level on admission was not low enough to have caused ischemic hepatitis by itself, we suspect that a sudden decrease in portal blood flow was the additional factor that allowed the threshold for the initiation of ischemic liver damage to be reached.

Aged↗

Glucocorticoids regulate pituitary growth hormone secretagogue receptor gene expression.

Glucocorticoids regulate growth hormone (GH) secretion by modulating both hypothalamic and pituitary function. At the level of the pituitary, glucocorticoids increase GH and GH-releasing hormone receptor (GHRH-R) gene expression. To test if glucocorticoids might also regulate the pituitary expression of the recently identified GH secretagogue (GHS) receptor, GHS-R; adult male rats were adrenalectomized or sham operated, and treated with the synthetic glucocorticoid (dexamethasone, 200 microg/day) or vehicle for 8 days. Pituitary GHS-R mRNA levels were assessed by reverse transcriptase polymerase chain reaction (RT-PCR). Adrenalectomy decreased pituitary GHS-R mRNA to 45% of vehicle-treated, sham-operated rats (P < 0.05). Administration of dexamethasone increased GHS-R mRNA levels in sham-operated as well as in adrenalectomized rats (199 +/- 24% (P < 0.05) and 369 +/- 48% (P < 0.01) of vehicle-treated controls). Addition of dexamethasone to primary rat pituitary cell cultures increased GHS-R mRNA levels in a dose- and time-dependent manner while the transcriptional inhibitor, actinomycin D, completely blocked the stimulatory action of dexamethasone. Taken together, these results suggest glucocorticoids directly increase pituitary GHS-R mRNA levels by stimulating GHS-R gene transcription.

Adrenalectomy↗

Masculinizing effect of dihydrotestosterone on growth hormone secretion is inhibited in ovariectomized rats with anterolateral deafferentation of the medial basal hypothalamus or in intact female rats.

There is a striking sex difference in the pattern of growth hormone (GH) secretion in rats. Our previous studies showed that short-term administration of pharmacological doses of testosterone or dihydrotestosterone (DHT) masculinized the GH secretory pattern in ovariectomized (OVX) rats. The locus where testosterone or DHT interacts with the somatotropic axis is believed to be the hypothalamus. To obtain insights into this phenomenon, we administered a single dose of DHT s.c. to adult OVX rats at 0.01, 0. 1 or 1 mg/rat. Blood GH concentrations were measured in unanaesthetized rats. Six to 12 h after the s.c. administration of all three doses of DHT, the GH secretory pattern revealed a male-like secretory pattern as shown by episodic bursts occurring at 2-3-h intervals with low or undetectable trough levels. When anterolateral deafferentation of the medial basal hypothalamus (ALC) was performed, the blood concentrations revealed irregularly occurring small fluctuations, instead of the usual high bursts, but the basal GH concentration was significantly higher than that of OVX-sham-operated rats. DHT treatment did not elicit pulsatile GH secretion or alter GH concentrations in OVX rats with ALC. When intact adult female rats received DHT at a dose of 1 mg/rat, the male-like GH secretory pattern was not induced. These results suggest that neural inputs from the anterolateral direction to the medial basal hypothalamus are necessary for the masculinizing effect of DHT on the GH secretory pattern in OVX rats, and that oestrogen in intact female rats prevents the masculinizing effect of DHT.

Afferent Pathways↗

Case of mesothelioma of the tunica vaginalis testis with characteristic findings on ultrasonography and magnetic resonance imaging.

A case of mesothelioma of the right tunica vaginalis testis in a 32-year-old man is reported. Trans-scrotal ultrasonography revealed hydrocele and multiple nodular masses measuring 1.0-4.5 cm in size attached to the parietal vaginal layer. Magnetic resonance imaging demonstrated more clearly nodular masses with irregular surfaces lined on the hydrocele cavity. Histologic diagnosis of the tumor when orchiectomized was mesothelioma. The patient has been free of disease for approximately 3 years since the treatment.

Adult↗

Growth factor-expressing mast cells accumulate at the thyroid tissue-regenerative site of subacute thyroiditis.

The localization and biological roles of the multifunctional cell type mast cells remain unclear in subacute thyroiditis that is characterized by both epithelioid granuloma formation and thyroid tissue repair. We examined their immunolocalization with tryptase of a mast cell marker, using the biopsy specimens from 12 cases. In the epithelioid granuloma, no mast cells were detected in any of the cases, although a small number of them (4.6 +/- 2.4) were seen at the fibrous stroma around the granuloma in all cases. By contrast, in all cases, increased mast cells (28 +/- 7.2) localized at the thyroid tissue-regenerative site where both thyroid folliculogenesis and angiogenesis take place. To elucidate possible roles of mast cells in the disease, we also examined their immunoexpressions of vascular endothelial cell growth factor (VEGF), basic fibroblast growth factor (bFGF), platelet-derived growth factor-BB (PDGF), transforming growth factor-beta1 (TGF-beta1) and epidermal growth factor (EGF), which affect thyroid folliculogenesis and angiogenesis. In all 12 cases, mast cells displayed all of these growth factors in a manner not specific to the infiltrating site. The data suggest that growth factor-expressing mast cells may play crucial roles in the thyroid tissue repair of subacute thyroiditis, modulating thyroid folliculogenesis and angiogenesis; and that the multifunctionality of the cells may be partly dependent on their expressions of various growth factors.

Acute Disease↗

A subpopulation of fibroblast growth factor-2-binding heparan sulfate is lost in human papillary thyroid carcinomas.

We hypothesized that a change in composition of proteoglycans can regulate the bioactivity of fibroblast growth factor (FGF)-2 in the thyroid. In order to test this hypothesis, we established a simple and sensitive method for detecting FGF-2-binding heparan sulfates and characterized them in papillary thyroid carcinomas and normal thyroids. The thyroid extracts were applied to a Q-Sepharose anion exchange column. After the column was washed with 10 mM of phosphate buffer, 1 microgram of human recombinant FGF-2 was added onto the column. The column was eluted with a gradient of NaCl (0.3-1.5 M). Each fraction was blotted onto nitrocellulose membrane. Immunoreactivity of heparan sulfate and FGF-2 was revealed by the incubation of membranes with the specific antibodies, and quantitatively estimated by measuring the density of the color product. In normal thyroids, immunoreactivity of heparan sulfate was detected as two peaks at 0.7 and 0.9 M of NaCl. Heparan sulfate-containing fractions also showed FGF-2 immunoreactivity, indicating the complex formation of FGF-2 and heparan sulfate. In papillary thyroid carcinomas, immunoreactivity of heparan sulfate showed various elution profiles on Q-Sepharose chromatography, including single peak at 0.7 M of NaCl and the one similar to that of the normal thyroids. However, FGF-2 immunoreactivity was detected only in the fractions eluting at 0.7 M of NaCl. This loss of a subpopulation of FGF-2-binding heparan sulfate in human papillary thyroid carcinomas may lead to the increase of free FGF-2 bioavailable in extracellular matrix.

Anion Exchange Resins↗