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Biomedical subjects

H Kataoka

Publications and source records attributed to H Kataoka.

At least 109 records · Page 6Linked to original sources

Endoscopic surgery for a parathyroid functioning adenoma resection with the neck region-lifting method.

Recently, endoscopic surgery has been applied to cervical exploration. We have developed new techniques for endoscopic neck surgery. We reported on a 53-year-old Japanese man with functioning parathyroid adenoma resected by endoscopic surgery with a neck region-lifting method. A 10-mm midline trocar for the endoscope and two 5-mm lateral trocars were inserted from the anterior chest wall to avoid neck scars. There were no intraoperative complications. The incisions were completely covered by the patient's undergarments.

Adenoma↗

Dentin bonding and sealing ability of a new root canal resin sealer.

The aims of this study were to find a dentin bonding system suitable for root canal treatment using a newly developed root canal resin sealer, and to examine its sealing ability. The sealer was composed of vinylidene fluoride/hexafluoropropylene copolymer, methyl methacrylate, zirconia, and tributylborane catalyst. The effects of dentin conditioners and primers on dentin bonding were studied by tensile bond strength testing and scanning electron microscopy. Apical and coronal leakage were evaluated at 1-, 4-, and 12-wk intervals by a dye penetration test using a methylene blue solution. Pulp Canal Sealer EWT and Sealapex were used as controls. Significantly high bond strength was obtained by treating dentin with EDTA, followed by application of a glutaraldehyde/2-hydroxyethyl methacrylate primer. The experimental resin sealer produced a significantly superior coronal seal at 12 wk when compared with the two control sealers (p < 0.05). Scanning electron microscopic examination revealed few gaps at the resin sealer-dentin interface.

Alkenes↗

Successful treatment of percutaneous transhepatic papillary dilation in patients with obstructive jaundice due to common bile duct stones after Billroth II gastrectomy: report of two emergent cases.

Successful treatment of two patients with obstructive jaundice due to choledocholithiasis after Billroth II gastrectomy was performed by elimination of stones by percutaneous transhepatic balloon dilatation of the sphincter of Oddi. Patient 1 was an 82-year-old man and Patient 2 was a 73-year-old man. Both patients presented with obstructive jaundice. The papilla was not observed in either patient because of previous Billroth II gastrectomy. Because an endoscopic approach was impossible, percutaneous transhepatic cholangiodrainage (PTCD) was performed to alleviate jaundice. Choledocholithiasis was treated as follows: The sphincter of Oddi was dilated by percutaneous transhepatic balloon, and stone particles were removed from the papilla with a stone-eliminating balloon catheter via the same route of PTCD. This method is less invasive than the percutaneous transhepatic cholangioscopic method, and the use of existing appliances such as a balloon for papillary dilation is possible. Hence, this method appears to be an effective and simple method for the treatment of choledocholithiasis after gastrectomy that is difficult to treat endoscopically.

Aged↗

Oxidized-LDL and atherosclerosis. Role of LOX-1.

The accumulation of substantial numbers of monocyte/macrophages and activated T lymphocytes in focal areas of the arterial intima appears to be a hallmark of atherosclerosis. Our report demonstrated that lysophosphatidylcholine (lyso-PC), a polar phospholipid component that is increased in atherosclerotic lipoproteins, such as oxidized LDL and remnant lipoproteins in diabetic and Type 3 hyperlipidemia, can upregulate adhesion molecules for monocytes and T lymphocytes, and growth factors, such as heparin-binding epidermal growth factor-like growth factor and PDGF A and B chains. Recently, we identified the novel receptor for oxidized LDL, named LOX-1. We summarize the importance of the interaction between oxidized LDL and its receptor, LOX-1, in terms of early stage atherogenesis.

Animals↗

Inducible expression of LOX-1, a novel receptor for oxidized LDL, in macrophages and vascular smooth muscle cells.

Macrophages appear to take up oxidized low density lipoprotein (Ox-LDL) by multiple receptor-mediated pathways. This study, therefore, has been performed to determine if LOX-1, a novel receptor for Ox-LDL, which was identified in vascular endothelial cells, is also expressed in macrophages. Expression of LOX-1 can be induced after macrophage-like differentiation in human peripheral blood monocytes as well as THP-1 cells. Furthermore, expression of LOX-1 in macrophages is also upregulated by an inflammatory cytokine TNF-alpha, which was shown to be present in atherosclerotic arterial wall. Expression of this novel receptor LOX-1 may play an important role in Ox-LDL uptake and subsequent foam cell formation in macrophages.

Animals↗

Upregulation of HGF activator inhibitor type 1 but not type 2 along with regeneration of intestinal mucosa.

Hepatocyte growth factor (HGF) activator inhibitor type 1 (HAI-1) and type 2 (HAI-2) are new Kunitz-type serine protease inhibitors that were recently purified and cloned from the human stomach cancer cell line MKN45 as specific inhibitors against HGF activator. Both proteins contain two Kunitz inhibitor domains and are expressed abundantly throughout the gastrointestinal tract, in addition to the placenta, pancreas, and kidney. In this study, to assess the possible roles of HAI-1 and HAI-2 in the intestinal mucosa, we examined the expression of HAI-1 and HAI-2 during regeneration of the intestinal mucosa. Immunohistochemical studies revealed that HAI-1 but not HAI-2 was detected more strongly in regenerative epithelium than in normal epithelium, although both proteins were detected throughout the human gastrointestinal tract. During the course of acetic acid-induced experimental colitis in an in vivo mouse model, HAI-1 but not HAI-2 was upregulated in the recovery phase, suggesting that HAI-1 but not HAI-2 is associated with the regeneration of damaged colonic mucosa. Upregulation of HAI-1 may serve to downregulate the proliferative response after initial activation of MET receptor by HGF/scatter factor after an injury.

Acetic Acid↗

Chronic treatment with angiotensin II type 1 receptor antagonist suppresses glomerular activator protein-1 activity in salt-sensitive hypertensive rats.

We examined the effects of angiotensin-converting enzyme inhibitor (ACEI) and angiotensin II type 1 receptor antagonist (AT1a) on the action of protooncogene c-fos in salt-sensitive hypertensive rats. Seven-week old Dahl salt-sensitive rats fed a high (8%)-salt diet were treated with ACEI, cilazapril (10 mg/kg) or AT1a, TCV-116 (1mg/ kg) every day for 6 weeks. The control animals were fed a low (0. 3%)-salt diet. Systolic blood pressure gradually increased in high-salt-loaded rats and was higher than low-salt-treated rats throughout the study. However, both medications had no significant antihypertensive effect. After 6 weeks of therapy, glomerular mRNA and nuclear protein were extracted from the resected kidneys. Competitive reverse transcription-polymerase chain reaction showed a high level of glomerular c-fos mRNA in high-salt-loaded rats and that ACEI or AT1a treatment did not significantly change its level. Electrophoretic mobility shift assay demonstrated that treatment with AT1a significantly decreased the activator protein-1 (AP-1) binding activity in the glomerular nuclear extract compared to ACEI. Our findings suggest that, compared with ACEI treatment, long-term treatment with AT1a may contribute to attenuation of the glomerular injury in salt-sensitive hypertension by inhibiting AP-1 transcription activity independent of its antihypertensive effect.

Angiotensin Receptor Antagonists↗

Identification of soluble forms of lectin-like oxidized LDL receptor-1.

Lectin-like oxidized LDL receptor-1 (LOX-1) is a type II membrane protein belonging to the C-type lectin family molecules, which can act as a cell-surface endocytosis receptor for atherogenic oxidized LDL. In this study, we show that soluble forms of LOX-1 are present in conditioned media of cultured bovine aortic endothelial cells (BAECs) and CHO-K1 cells stably transfected with LOX-1 cDNA. Immunoblot analysis of conditioned media from TNF-alpha-activated BAECs and CHO-K1 cells stably expressing LOX-1 revealed that soluble LOX-1 has an approximate molecular mass of 35 kDa. In TNF-alpha-activated BAECs, cell-surface expression of LOX-1 precedes soluble LOX-1 production. Cell-surface biotinylation followed by immunoprecipitation and immunoblotting showed that soluble LOX-1 in cell-conditioned media is derived from LOX-1 expressed on the cell surface. Production of soluble LOX-1 was inhibited by PMSF, suggesting that PMSF-sensitive proteases may be involved in this process. Purification of soluble LOX-1 by high-performance liquid chromatography and N-terminal amino acid sequencing of soluble LOX-1 identified the 2 cleavage sites between Arg(86)-Ser(87) and Lys(89)-Ser(90), which were located in the membrane proximal extracellular domain of LOX-1. The data demonstrate that cell-surface LOX-1 can be cleaved at 2 different sites and transformed into soluble forms. Further studies may explore therapeutic and diagnostic applications of soluble LOX-1 in atherosclerotic diseases.

Amino Acid Sequence↗

Increased expression of lectin-like oxidized low density lipoprotein receptor-1 in initial atherosclerotic lesions of Watanabe heritable hyperlipidemic rabbits.

A novel lectin-like oxidized low density lipoprotein receptor-1 (LOX-1) was recently identified in bovine aortic endothelial cells. It is strongly suggested to have a potential role in the initiation and development of atherosclerosis. In this study, we have isolated cDNA clones encoding the rabbit homologue of LOX-1 by screening a rabbit placenta cDNA library. In amino acid sequence and domain structure organization, the rabbit LOX-1 is highly conserved with the human counterpart. Transfection of rabbit LOX-1 cDNA to HEK-293 cells confers on them the activity to bind and internalize oxidized low density lipoprotein. Rabbit LOX-1 was identified as a 45-kDa protein by Western blot analysis with a specific monoclonal antibody. Notably, analyses by reverse transcription-polymerase chain reaction and Western blot revealed that LOX-1 was accumulated in 8-week-old Watanabe heritable hyperlipidemic rabbit aortas compared with normal rabbit aortas. Immunostaining confirmed that the augmented expression of LOX-1 was primarily localized within the intima at the earliest stages of atherogenesis. The most prominent staining was in the endothelial cells of lesions. Furthermore, the distinctive staining of LOX-1 was identified in the endothelium of non-lesion areas of Watanabe heritable hyperlipidemic rabbit aortas. Taken together, these findings support the possibility that LOX-1 might be involved in the initiation of atherosclerosis.

Amino Acid Sequence↗

Hyperthyroidism in a patient with TSH-producing pituitary adenoma coexisting with thyroid papillary adenocarcinoma.

A 27-year-old woman who presented with a left thyroid nodule was found to have hyperthyroidism caused by a syndrome of inappropriate secretion of TSH. The levels of free T3, free T4 and TSH were 9.50 pg/mL, 4.05 ng/dL and 2.16 microU/mL, respectively. Magnetic resonance imaging of the head revealed a pituitary macroadenoma. The TSH response to TRH stimulation was normal and responses of other anterior pituitary hormones to stimulation tests were also normally preserved. Administration of octreotide with iodine successfully reversed hyperthyroidism prior to total resection of pituitary adenoma, which was followed by hemithyroidectomy of the left thyroid five months later. Histologically, the resected pituitary adenoma was a TSH-producing adenoma (TSH-oma) and the thyroid nodule was a papillary adenocarcinoma. Serum TSH diminished to undetectable levels immediately following pituitary adenomectomy but gradually normalized over nine months. Coexistence of a TSH-oma with thyroid cancer is very rare and only two similar cases have previously been documented. This combination raises the possibility that TSH may be involved in tumorigenesis in the thyroid gland.

Adenocarcinoma, Papillary↗

[A case of Fisher syndrome showing pharyngeal-cervical-brachial weakness with an elevation of anti-GQ 1 b and anti-GT 1 a antibodies].

A 15-year-old boy developed ataxic gait, diplopia and hoarseness. Within 3 days after the onset, he had additional symptoms of dysphagia and dysarthria. He was admitted to our hospital 7 days after the onset of the disease. On admission, he had total ophthalmoplegia, ataxia, areflexia, facial diplegia, bulbar palsy and weakness of the neck and upper arms. Serum anti-GQ 1 b and anti-GT 1 a antibodies were significantly elevated. A diagnosis of Fisher syndrome associated with pharyngeal-cervical-brachial weakness was made. He was placed on a high dose of intravenous immunoglobins (12.5 g/day x 2 days) and had steroid pulse therapy (methylprednisolone 1 g x 3 days), which resulted in an almost complete recovery. There have been no reports of Fisher syndrome associated with brachio-pharyngeal-palsy. As in the case of the pharyngeal-cervical-brachial variant of Guillain Barré syndrome, anti-GT 1 a antibodies may be associated with Fisher syndrome with pharyngeal-cervical-brachial weakness.

Adolescent↗

[Communications among components of automated clinical laboratory systems].

Laboratory Automation Systems has been developed with original specifications from each vender. To construct a system in a multi-vender environment, remodeling of the interface and software had to be done by the user. The standard concerning automated laboratory systems was made by NCCLS in 1997. This standard provides a protocol for communications among Laboratory Automation Systems(LAS), Laboratory Information Systems(LIS), automated instruments (analyzers), and pre- and post-analytical automated devices. This document explains the current details and the overall content of the communication standards for automated laboratory systems developed by the NCCLS Subcommittee on Communications between Automation Systems.

Autoanalysis↗

[Two cases of cranial pachymeningitis presenting only severe continuous headache or convulsion].

In cranial pachymeningitis, headache, cranial nerve palsies, and ataxia were the most common clinical manifestations. We reported two rare cases presenting only headache or convulsion as a main symptom. A 66-year-old man was suffering from severe continuous headache for years with no other clinical symptoms. Laboratory data revealed positive RA test and elevated RAPA. With oral steroid therapy, his headache was subsided. A 39-year-old woman visited us with convulsive attacks as only symptom. Biopsy of the thickened dura revealed granulated epithelioid cells without central necrosis. With antituberculosis therapy, hypertrophy of dura, as well as the symptom, was disappeared. It is difficult to diagnose pachymeningitis when patients manifest only headache or convulsion. We suggest to carry out Gd-enhanced MR scan in these cases.

Adult↗

Prothoracicotropic activity of SBRPs, the insulin-like peptides of the saturniid silkworm Samia cynthia ricini.

Synthesis and secretion of the insect molting hormone ecdysteroid in the prothoracic glands (PGs) are stimulated by the prothoracicotropic hormone (PTTH) secreted by the brain. Bombyxins, insulin-like peptides of the silkworm Bombyx mori, show prothoracicotropic activity when administered to the saturniid silkworm Samia cynthia ricini, but they are inactive to B. mori itself. Recently, the genes for the bombyxin homologs of S. cynthia ricini (referred to as Samia bombyxin-related peptides, SBRPs) were cloned. To examine the prothoracicotropic activity of SBRPs on S. cynthia ricini, we synthesized two representative molecules, SBRP-A1 and -B1. They promoted pupa-to-adult development with ED(50) of 50 and 10 ng/pupa (EC(50) of 5 and 1 nM), respectively.

Amino Acid Sequence↗