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Biomedical subjects

H Kataoka

Publications and source records attributed to H Kataoka.

At least 145 records · Page 8Linked to original sources
PubMed1999

Isolation and structure determination of a paralytic peptide from the hemolymph of the silkworm, Bombyx mori.

A peptide with paralytic activity in larvae of the silkworm, Bombyx mori, was isolated from its hemolymph. Purification procedures consisted of extraction with 50% acetone, Vydac C4 reversed-phase cartridge elution and 4 steps of reversed-phase HPLC. Injection of the purified peptide into 4th instar B. mori larvae caused rapid and rigid paralysis for 2 min at a dose of 3.4 ng/larva. This paralytic peptide consists of 23 amino acid residues containing 2 cysteines with an intra-disulfide bond. The complete amino acid sequence is: H-Glu-AsnPhe-Val-Gly-Gly-Cys-Ala-Thr-Gly-Phe-Lys-Arg-Thr-Ala-Asp-G ly-Arg-Cys-Lys-Pro-Thr-Phe-OH. The relationship between structure and the biologic activity of synthetic analogs indicated that the entire amino acid sequence and the intra-disulfide bond were necessary for biological activity.

Amino Acid Sequence↗
PubMed1999

The BMP-related protein radar: a maintenance factor for dorsal neuroectoderm cells?

We have previously cloned several members of the TGF-beta superfamily of growth factors in zebrafish, one of which, Radar, belongs to the Dpp-Vg1-related (DVR) subgroup, with highest homology to GDF6. The pattern of expression of Radar suggested a possible involvement in several induction steps during embryogenesis including in the dorsal neural tube, red blood cells, the dorsal fin and the retina. We have analyzed the pattern of expression of Radar in comparison with that of a marker of dorsal neural tube structures, msxC and show that Radar and msxC are expressed in similar and/or adjacent tissues throughout embryogenesis. In order to demonstrate a functional relationship between these two proteins, we have generated a full-length cDNA for Radar and shown that Radar overexpression by DNA injection maintains expression of msxC in tissues where it is normally expressed then turned off, in particular in the dorsal neurectoderm. Study of the phenotype of a mutant carrying a deletion of Radar shows a loss of identity and death of the cells of the dorsal neural tube. Taken together these results suggest that Radar could be involved in maintaining the identity of cells of the dorsal-most neural tube and of at least a subset of neural crest cells.

Amino Acid Sequence↗
PubMed1999

Simultaneous up-regulation of urokinase-type plasminogen activator (uPA) and uPA receptor by hepatocyte growth factor/scatter factor in human glioma cells.

Several lines of evidence indicate that hepatocyte growth factor/scatter factor (HGF/SF) and its receptor, c-Met, may play an important role in progression of human glioma. In this study, effects of HGF/SF on urokinase- type plasminogen activator (uPA)-mediated proteolysis network were examined in c-Met-positive human glioma cell lines. Treatment of the glioma cells with various concentrations of HGF/SF resulted in an enhanced secretion of uPA proteins accompanying increased transcription of uPA mRNA in a dose dependent fashion. The levels of uPA receptor (uPAR) mRNAs were also elevated simultaneously upon HGF/SF stimulation, and the cell-surface associated uPA activity was also elevated by the treatment. Since concomitant expression of HGF and its receptor c-Met are frequently observed in malignant gliomas, these results suggest that HGF/SF participates in invasive process of malignant glioma cells not only by its motility-stimulating activity but also through enhanced degradation of the extracellular matrix induced by autocrine activation of uPA proteolysis network.

Central Nervous System Neoplasms↗
PubMed1999

Retroperitoneal bronchogenic cyst: report of a case and literature review.

A large cystic mass was found in the subdiaphragmatic region of a 46-year-old woman who had complained of continuous pain in the left flank . The cyst was located in the retroperitoneum just below the diaphragm and was adhered to the diaphragmatic skeletal muscle and abdominal aorta, but was separate from the spleen, pancreas, left adrenal gland and left kidney. The surgically resected cyst measured 8 x 8 x 7 cm and was filled with protein-rich fluid, which contained amylase and embryonal proteins such as carcinoembryonic antigen, CA125 and CA19-9. Histologically, the cyst wall was composed of a fibrovascular connective tissue containing thin smooth muscle layers and mucus-secreting glands and was lined by a ciliated pseudostratified or tall columnar epithelium without dysplastic changes. Thus, a diagnosis of bronchogenic cyst, which is usually discovered in the posterior part of the mediastinum, was made. A rare case of bronchogenic cyst and a literature review is presented.

Biomarkers↗
PubMed1999

Aeromonas sobria infection with severe soft tissue damage and segmental necrotizing gastroenteritis in a patient with alcoholic liver cirrhosis.

A 49-year-old man, who had a 3-year history of liver dysfunction but had not been treated, was admitted to the hospital with a sudden onset of fever and generalized muscle pain. He subsequently developed generalized purpura with scattered hemorrhagic bullae of the skin and massive bloody stools. Aeromonas sobria was proven by culture of both blood and bullous fluid. In spite of the extensive treatment with antibiotics and other medications in the intensive care unit (ICU), the patient went into septic shock and died 2 days after admission. Pathological examination on autopsy revealed segmental necrotizing gastroenteritis with bacterial colonies and alcoholic liver cirrhosis, in addition to extensive severe soft tissue damage involving cellulitis and rhabdomyolysis and epidermolysis. Although the prognosis for Vibrio vulnificus infection with severe soft tissue damage in patients with liver cirrhosis, malignancy, diabetes mellitus or other pre-existing diseases is poor, the unfavorable progression of Aeromonas species, especially A. sobria infection is rare. This is thought to be the first report of an autopsied case.

Aeromonas↗
PubMed1999

Solitary fibrous tumor of the spinal nerve rootlet: case report and literature survey.

Solitary fibrous tumor (SFT) is a rare tumor that arises most commonly in the pleura. Recent evidence indicated that it is a tumor that originates from mesenchymal, probably fibroblastic, cells and is not restricted to the pleura. This report presents a case of primary SFT occurring as a dumbbell-shaped tumor of the cervical spine (C4/5) in a 46-year-old Japanese female, probably originating from the spinal rootlet. The tumor was predominantly extradural, loosely attached to the dura mater, with a small intradural extramedullary part attached to the C5 anterior and posterior rootlets. Histologically, the tumor was predominantly composed of a haphazard proliferation of spindle cells separated by abundant collagen. Immunohistochemically, the cells were strongly positive for CD34, bcl-2 and vimentin, but were negative for S-100 protein, neuron specific enolase, cytokeratin and epithelial membrane antigen. The present case and review of the literature strongly suggest that SFT is an entity that should be considered in the differential diagnosis of tumors of the cerebrospinal region.

Antigens, Nuclear↗
PubMed1999

Long-term administration of adrenocorticotropin modulates the expression of IGF-I and TGF-beta 1 mRNAs in the rat adrenal cortex.

The effects of long-term adrenocorticotropin (ACTH) therapy on the expression of IGF-I and TGF-beta 1 on rat adrenal cortex was investigated. ACTH (0.1 mg/kg/day) or saline as control was injected intraperitoneally in 5-week-old Wistar rats every day for 4 weeks. ACTH significantly increased adrenal weight (P < 0.05) and serum corticosterone (P < 0.05). Competitive RT-PCR analysis on the adrenocortical mRNA showed increased IGF-I (P < 0.01) at 4 weeks of ACTH and increased TGF-beta 1 (P < 0.01) at 1 week of ACTH compared the control group. ACTH also significantly increased proliferating cell nuclear antigen mRNA level (P < 0.01), at 4 weeks of treatment, which correlated with IGF-I level (P < 0.01), but correlated negatively with ACTH-stimulated TGF-beta 1 level (P < 0.05). There was a weak correlation between IGF-I and serum corticosterone (P < 0.05), and between TGF-beta 1 mRNA levels and serum corticosterone concentration (P < 0.05). Histologically, ACTH induced hypertrophy in the zona fasciculata cells and increased the clear cells containing lipid deposits. Immunohistochemistry showed that IGF-I peptide was mainly expressed in the periphery of the zona fasciculata at 4 weeks of ACTH therapy, while the same therapy caused a slight increase in TGF-beta 1 expression in the same area. Our results show that an increase in adrenocortical growth resulting from ACTH treatment is associated with an increase in IGF-I mRNA expression but only a transient increase in TGF-beta 1 mRNA expression.

Adrenal Cortex↗
PubMed1999

Comparative study of vocal function after near-total laryngectomy.

OBJECTIVES: To assess vocal function after near-total laryngectomy (NTL) and to compare that with after vertical hemilaryngectomy (VHL), both of which use the laryngeal mucosa as the vibratory tissue. STUDY DESIGN: We retrospectively evaluated 29 patients, 11 of whom underwent NTL and 18 of whom underwent VHL. However, 2 patients failed to speak and 1 patient's voice sample was lost following NTL, so we analyzed the voices of 8 patients who underwent NTL and 18 patients who underwent VHL. METHODS: Vocal function was examined by acoustic and aerodynamic analysis. Acoustic analysis involved the evaluation of pitch, intensity, pitch perturbation quotient, amplitude perturbation quotient, and normalized noise energy. In aerodynamic analysis, we studied the mean airflow rate, vocal efficiency index (alternating current/direct current [AC/DC]), and maximum phonation time. RESULTS: Vocal function except pitch after either NTL or VHL had much variability, but the results following each procedure did not differ significantly. CONCLUSIONS: There are no significant differences between vocal function following NTL and VHL. Fiberscopic examination of the mucosa of the arytenoid was observed to vibrate in patients who underwent NTL, so that the phonatory mechanism after NTL resembled that after VHL.

Adult↗
PubMed1999

Atrioventricular dissociation as a cause of syncope determined by head-up tilt test.

This report describes a patient with syncopal attacks in a sitting position on a reclining seat, in whom atrioventricular dissociation due to accelerated ventricular rhythm was determined to be the cause by recording of the electrocardiogram, blood pressure, and mitral and aortic Doppler flow during a 60 degree head-up tilt test.

Aortic Valve↗
PubMed1999

Carcinoembryonic antigen and carbohydrate antigen 19-9-producing adenocarcinoma of the prostate: report of an autopsy case.

Prostate-specific antigen (PSA) and prostatic acid phosphatase (PAP) are well known as specific tumor markers of prostate cancer, but carcinoembryonic antigen (CEA)- and carbohydrate antigen 19-9 (CA19-9)-producing adenocarcinoma originating in the prostate is rare. We report here a case of prostatic adenocarcinoma positive for these 4 tumor markers in a 50-year-old man who had initially complained about chest pain due to metastatic bone tumor. In spite of the extensive treatment involving hormone and radiation therapy, the patient died of rapid tumor extension only 4 months after initial diagnosis. Autopsy revealed multiple metastases to the bone, liver, lungs and lymph nodes. Histologically, two types of adenocarcinoma were involved in both primary prostate and metastatic sites: one was a poorly differentiated adenocarcinoma positive for PSA and PAP but not CEA or CA19-9, and the other one was a less differentiated adenocarcinoma partially positive for CEA and CA19-9 but not for PSA or PAP. Based on this case and previous cases by review of the literature, CEA- and CA19-9-producing adenocarcinoma of the prostate was suggested to rapidly progress with multiple metastases and to show poor prognosis with strong resistance to any treatment.

Acid Phosphatase↗
PubMed1999

Distribution of hepatocyte growth factor activator inhibitor type 1 (HAI-1) in human tissues. Cellular surface localization of HAI-1 in simple columnar epithelium and its modulated expression in injured and regenerative tissues.

We used a specific monoclonal antibody to human hepatocyte growth factor activator inhibitor type 1 (HAI-1) in immunohistochemical procedures to determine the distribution and localization of HAI-1 in human tissues. In normal adult tissues, HAI-1 was predominantly expressed in the simple columnar epithelium of the ducts, tubules, and mucosal surface of various organs. In all cases, HAI-1 was localized predominantly on the cellular lateral (or basolateral) surface. By contrast, hepatocytes, acinar cells, endocrine cells, stromal mesenchymal cells, and inflammatory cells were hardly stainable with the antibody, and stratified squamous epithelium showed only faint immunoreactivity on the surface of cells of the basal layer. In the gastrointestinal tract, the surface epithelium was strongly stained. RNA blot analysis confirmed the presence of specific mRNA transcript in the gastrointestinal mucosa, and in situ hybridization revealed that HAI-1 mRNA showed a similar cellular distribution pattern. Although HAI-1 was not expressed in normal hepatocytes, strong immunoreactivity was observed on the epithelium of pseudo-bile ducts and on the surface of scattered hepatocytes in fulminant hepatitis. The enhanced expression was also noted in regenerating tubule epithelial cells of the kidney after infarction. We conclude that HAI-1 is preferentially expressed in the simple columnar epithelium of the mucosal surface and duct, that the predominant localization of HAI-1 is the cell surface, and that the expression of HAI-1 can be modulated by tissue injury and regeneration.

Antibodies, Monoclonal↗
PubMed1999

Effect of caffeine on ibuprofen-induced gastric mucosal damage in rats.

During investigations on the effect of caffeine on ibuprofen-induced gastric mucosal lesions in rats, we have found that caffeine (p.o.) inhibits the development of ibuprofen-induced gastric lesions in a dose-dependent manner (ED50 18.4 mg kg(-1)). To investigate this protective effect of caffeine, we have studied the effect of caffeine on HCl-ethanol-induced gastric mucosal lesions with or without indomethacin pretreatment. Caffeine inhibited the development of HCl-ethanol-induced gastric lesions with and without indomethacin pretreatment. These results indicate that caffeine did not act as a mild irritant but, on the contrary, had protective effects. We measured the gastric mucosal prostaglandin E2 (PGE2) concentrations and gastric mucosal blood flow, as representative protective factors for gastric mucosa. Caffeine did not affect the gastric mucosal PGE2 concentrations 4h after administration of ibuprofen. However, topical administration of caffeine resulted in an increase in gastric mucosal blood flow, as measured by laser Doppler flowmetry. We investigated the gastric acid secretion and gastric mucosal myeloperoxidase activity as representative aggressive factors for gastric mucosa. When caffeine was administered intraduodenally in pylorus-ligated rats, gastric acid secretion decreased in a dose-dependent manner, with an ED50 of 44.9 mg kg(-1). Caffeine decreased ibuprofen-induced gastric myeloperoxidase activity in a dose-dependent manner, with an ED50 of 9.1 mg kg(-1). These findings indicate that caffeine, at least in rats, may inhibit the development of acute gastric mucosal injury. The mechanisms underlying the protective actions of caffeine are unclear, but may be related in part to an increase in gastric mucosal blood flow and suppression of neutrophil activation.

Administration, Oral↗
PubMed1999

Suppression and enhancement of the Freund's incomplete adjuvant-induced writhing reaction by sodium ascorbate in mice.

We noticed that an intraperitoneal injection of Freund's incomplete adjuvant (FIA) into mice could stimulate the induction of a writhing reaction. The FIA emulsion-induced writhing reaction was found to be remarkably inhibited by preadministration of oral indomethacin, a non-steroidal anti-inflammatory and analgesic drug. The induction of the writhing reaction was also inhibited by intravenous preadministration of sodium ascorbate (SAs) in saline. In the experiments where SAs was added to FIA, it was demonstrated that SAs had dual activity of suppression and enhancement. At lower concentrations SAs functioned as a suppressor of the writhing reaction, while at concentrations higher than about 1 mg/50 microl/mouse it acted as an enhancer of the reaction. Furthermore, this writhing reaction induced by FIA+SAs emulsion was also inhibited by preadministraion of SAs itself as well as indomethacin. These results suggested that the mechanism of the writhing reaction induced by FIA was concerned with the production of prostaglandins (PGs), and SAs might be involved in regulation of the writhing reaction. In this paper, we propose a mouse writhing model induced by FIA or FIA+SAs emulsion as a novel pain model useful for assessment of analgesic and anti-inflammatory agents.

Analgesics↗
PubMed1999

Detection of anaphylactic reaction in the percutaneously sensitized mouse using the AW method.

Anaphylactic reactions of mice sensitized percutaneously with 2,4-dinitrofluorobenzene (DNFB) were investigated by the AW method assay, which is a mouse anaphylactic model using the abdominal wall as the site for induction with either 2,4-dinitrophenyl (DNP)-human serum albumin or anti-mouse IgE antibody and then estimation of the response. DNP-specific and IgE-dependent anaphylactic reaction after contact sensitization with DNFB could be induced and detected by the abdominal wall (AW) method assay in both groups with and without previous ear challenge with DNFB. Thus, the anaphylactic reaction in the group of twice-contact with 0.5% DNFB was observed on the 9th day from the sensitization (5th day from the ear challenge), and the reaction in the group of a single contact with 0.5% DNFB was observed 10 d after sensitization. The DNP-specific anaphylactic reaction was observed earlier than the 10th day with higher doses of DNFB. As for the mice of the former twice-contact group, the first and second characteristic ear swelling responses appeared within 1-6 h and 2 d of the ear challenge, respectively, and small swelling was observed 7 d after the challenge. It is suggested that Th1 and Th2 cells are activated at the almost same time, in other words, the preparation for both cell-mediated and humoral immunity could be accomplished to function, in vivo by a single percutaneous sensitization with DNFB.

Abdominal Muscles↗
PubMed1999

Cohort migration of carcinoma cells: differentiated colorectal carcinoma cells move as coherent cell clusters or sheets.

Active migration of tumor cells is usually assessed as single cell locomotion in vitro using Boyden chamber-type assays. In vivo, however, carcinoma cells, malignant cells of epithelial origin, frequently invade the surrounding tissue as coherent clusters or nests of cells. We have called this type of movement "cohort migration". In our work, the invasion front of colon carcinomas consisted of compact tumor glands, partially resolved glands or markedly resolved glands with scattered tumor cell clusters or single cells lying ahead. In the former two types, which constituted about a half of all cases, cohort migration seems to be the predominant mechanism, whereas both cohort migration and single cell locomotion may be involved in the last one. In this light, it is very advantageous to investigate the mechanisms involved in the cohort migration. In this review, we present a two-dimensional motility assay as a cohort migration model, in which human colorectal carcinoma cells move outwards from the cell islands mainly as localized coherent sheets of cells when stimulated with 12-O-tetradecanoylphorbol-13-acetate (TPA) or hepatocyte growth factor/scatter factor (HGF/SF). Within the migrating cell sheets, wide intercellular gaps occur at the lower portion of the cells to allow the cells to extend leading lamellae forward while close cell-cell contacts remain at the upper portion of the cells. This localized modulation of cell-cell adhesion at the lower portion of the cells is associated with increased tyrosine phosphorylation of the E-cadherin-catenin complex in TPA-induced cohort migration and with reduced alpha-catenin complexed with E-cadherin in HGF/SF-induced cohort migration. Furthermore, fibronectin deposited by migrating cells is essential for their movement, and on the gelatin-coated substrate even degradation and remodeling of the substrate by matrix metalloproteinases are also needed. Thus, in cohort migration it is likely that cells are released from cell-cell adhesion only at the lower portion of the cells via modulation of E-cadherin-catenin-based mechanism, and this change allows the cells to extend leading lamellae onto the extracellular matrix substrate remodeled by deposition of fibronectin and organized digestion.

Animals↗
PubMed1999

Giant insulinoma in a patient with multiple endocrine neoplasia-type I: a case report.

We report a case of giant cystic insulinoma constituting part of multiple endocrine neoplasia (MEN) type I. A 29-year-old Japanese man presented with a history of recurrent hypoglycemic attacks. Endocrine examination showed hyperinsulinemia discordant with hypoglycemia, and a giant cystic insulinoma (11 x 10 cm) located in the pancreatic tail was detected radiologically. Hyperprolactinemia due to pituitary adenoma and hyperparathyroidism due to parathyroid hyperplasia were also present. The insulinoma, prolactinoma and hyperplastic parathyroid gland were surgically removed. Fluorescent microsatellite analysis detected loss of heterozygosity (LOH) in chromosome 11q13 in DNA samples from all resected tissues but not from white blood cells. This is a rare case of MEN type I because of the giant cystic insulinoma and the evidence of common LOH detected in all MEN type I tissues.

Adult↗
PubMed1999

Secretion of protease nexin-II/amyloid beta protein precursor by human colorectal carcinoma cells and its modulation by cytokines/growth factors and proteinase inhibitors.

Trypsin inhibitors secreted by human colorectal adenocarcinoma cell lines were analyzed by reverse zymography. Among eleven cell lines analyzed, the major inhibitor secreted was protease nexin-II (PN-II), a secreted form of amyloid beta protein precursor (APP) containing a Kunitz-type serine proteinase inhibitor domain. Expression of the APP gene was also confirmed in the cell lines and the main APP mRNA species were PN-II types. The APP gene expression was constant during cell growth in vitro. On the other hand, the rate of extracellular PN-II accumulation markedly increased after long-term serum-free maintenance of the confluent culture. The extracellular accumulation of PN-II was also strongly stimulated either by interleukin-1beta (IL-1beta) treatment or to a lesser extent by basic fibroblast growth factor, tumor necrosis factor-alpha, hepatocyte growth factor or epidermal growth factor. Neither serum depletion- nor IL-1beta-induced stimulation of extracellular PN-II accumulation were accompanied by obvious alteration of the levels of APP mRNA and cellular APP holoprotein, suggesting that the enhanced extracellular accumulation of PN-II might result from up-regulation of the secretory pathway of APP. The IL-1beta-induced PN-II secretion was significantly inhibited by relatively high concentrations (50-200 microg/ml) of aprotinin, a serine proteinase inhibitor, in a dose-dependent manner without obvious cell-toxic effects.

Adenocarcinoma↗