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Biomedical subjects

K Uehara

Publications and source records attributed to K Uehara.

At least 91 records · Page 5Linked to original sources
PubMed1994

Antigen levels of Dermatophagoides mites (Acari: Pyroglyphidae) in dust samples collected in homes of allergic patients.

A medical service system for testing antigen levels of Dermatophagoides farinae Hughes and D. pteronyssinus (Trouessart) mites in house dust was established to allow physicians to monitor the environment of patients with allergies. Dust samples were collected from a 1-m2 area at different sites for 1 min using a commercial collection apparatus attached to a vacuum cleaner. Extracts from fine dust fractions were processed quantitatively for antigen by a sandwich enzyme-linked immunosorbent assay. Mean antigen levels contained in samples from carpets, tatamis, and futons ranged from 431 to 852 micrograms per unit weight of dust (g). When data were expressed as micrograms per m2, the mean antigen level obtained from carpets (41 micrograms/m2) was significantly higher than that obtained from tatamis (15 micrograms/m2) and futons (14 micrograms/m2). Comparison of 37 paired samples collected from 10 homes at an interval of 1 to 2 mo indicated that high antigen levels of > 50 micrograms/m2 at four sites (three carpets and one tatami) decreased sharply after improvement of hygienic conditions surrounding allergic patients.

Animals↗
PubMed1994

Localization of metallothionein in aged human brain.

The localization of metallothionein (MT), a small molecular weight heavy metal binding protein in aged human brain, was investigated by immunohistochemical techniques. The amount of MT and heavy metals (Zn, Cu) were also assayed by radioimmunoassay and atomic absorption spectrophotometry, respectively. Immunohistochemically, MT was found in the pia mater, ependymal cells, protoplasmic astrocytes nand glial processes neuropil of the gray matter and fibrous astrocytes of the white matter of the telencephalon, whereas oligodendroglia and microglia did not show any positive immunostaining for MT. Cytoplasm, glial processes and some nuclei of protoplasmic and fibrous astrocytes showed strong MT immunostaining. Vascular feet and adventitia were also positive for MT immunostaining. Moreover, the pia mater, astrocytes and ependyma in the diencephalon, mesencephalon, pons, medulla oblongata and spinal cord showed the same positive immunostaining for MT as the telencephalon. In the cerebellum, Bergmann's glia, protoplasmic astrocytes of the granular layer and fibrous astrocytes of the white matter showed strongly positive immunostaining for MT. According to the radioimmunoassay, the amount of MT in the brain was relatively high at about 39.3 +/- 9.5 micrograms/g wet weight; of the heavy metals in the brain, zinc and copper were detected.

Age Factors↗
PubMed1994

Expression of stratified squamous epithelia-type cytokeratin by canine mammary epithelial cells during tumorigenesis: type I (acidic) 57 kilodalton cytokeratin could be a molecular marker for malignant transformation of mammary epithelial cells.

Two monoclonal antibodies (MAbs) were established in 20 clones of MAbs generated against cytokeratin fraction extracted from canine squamous cell carcinoma to investigate the expression of intermediate filament proteins during tumorigenesis. These MAbs were confirmed to react with purified cytokeratin by ELISA. One monoclonal antibody, MAb32 reacted all layers of epidermis except the cornified layer and mammary myoepithelial cells but not any epithelial cells. Another antibody named MAb24 exclusively reacted the basal monolayer of epidermis, the stratum germinativum. Any positive reactions with MAb24 were not detected in normal mammary gland. From the analysis by two-dimensional gel electrophoresis followed by immunoblotting, it was revealed that MAb24-recognizing cytokeratin subunit gave a molecular weight of 57 kilodalton and a isoelectric-pH value of pI5.1, indicating type I (acidic) cytokeratin. In intraductal papillomas developed in canine mammary glands, most tumor cells were positively stained with MAb32 in addition of myoepithelial cells while no positive reaction with MAb24 was seen. In ductal carcinomas, MAb24-positive cytokeratin was begun to express by tumor cells with positive reaction of MAb32 where these cells showed infiltrative growth into the stroma. We therefore proposed that 57 kilodalton-type I cytokeratin was a molecular marker for malignant transformation in canine mammary tumor and these antibodies could be useful tools to investigate the change of cytokeratin expression during tumorigenesis.

Adenofibroma↗
PubMed1994

Immunohistochemical examination of neural cell adhesion molecule (NCAM), tenascin and fibronectin on the development of cartilaginous tissue in canine mammary mixed tumors.

The expression of neural cell adhesion molecule (NCAM), tenascin and fibronectin during cartilage-like tissue formation in canine mammary mixed tumor was immunohistochemically examined. Mirror-image serial sections revealed that proliferating myoepithelial cells simultaneously expressed these adhesion molecules where no cartilage-like tissue and no expression of cartilage-specific type II collagen were observed. With the formation of cartilaginous tissue, positive signals of these adhesion molecules decreased in chondroblast-like cells, the cartilaginous tissue was hyalinized and mature chondrocyte-like cells no longer expressed these cell adhesion molecules. NCAM, tenascin and fibronectin, therefore, may play crucial roles on the proliferation of myoepithelial cells and the subsequent development of cartilaginous tissue in canine mammary mixed tumor.

Amino Acid Sequence↗
PubMed1994

[Effects of volatile anesthetics on microtubule-associated protein 2 degradation during forebrain ischemia in the rat].

One of the most prominent phenomena that occurs during the early phase of cerebral ischemia has been shown to be the immunohistochemical collapse of cytoskeletal proteins. Among these, microtubule-associated protein 2 (MAP 2) has been shown to be vulnerable to ischemic injuries. In order to select a suitable volatile anaesthetic from the standpoint of cytoskeletal protein breakdown during cerebral ischemia, we compared the effect of isoflurane, halothane and sevoflurane on MAP 2 degradation during 20 min of forebrain ischemia in the rat. Under 1 MAC of three volatile anesthetics, forebrain ischemia was induced by the occlusion of the bilateral common carotid artery combined with a lowering of mean arterial pressure to 50 mmHg. Immediately after cerebral ischemia, four regions of the brain, the frontoparietal cortex, brainstem, hippocampus and cerebellum, were removed separately and homogenized. Subsequently, MAP 2 from each region was quantitatively measured using an enzyme-linked immunosorbent assay. MAP 2 in the frontoparietal cortex and hippocampus was significantly protected from degradation with isoflurane anaesthesia more than with halothane and sevoflurane anaesthesia.

Anesthetics, Inhalation↗
PubMed1994

[Pulmonary sequestration diagnosed by combined computed tomography without contrast enhancement and magnetic resonance imaging: a case report].

A 71-year-old woman with pulmonary sequestration had iodine hypersensitivity. Diagnosis was made using computed tomography without contrast enhancement and magnetic resonance imaging. An anomalous artery arising from the descending thoracic aorta was clearly defined. Thus the diagnosis of pulmonary sequestration was confirmed before successful operation without angiography. This diagnostic procedure is safe, noninvasive and useful to detect the anomalous artery, especially in the patient with iodine hypersensitivity.

Aged↗
PubMed1993

The first application of a chemiluminescence probe, 2-methyl-6-[p-methoxyphenyl]-3,7-dihydroimidazo[1,2-a]pyrazin-3-one (MCLA), for detecting O2- production, in vitro, from Kupffer cells stimulated by phorbol myristate acetate.

The purpose of this study was to investigate the generation of superoxide anion radical, O2-, by Kupffer cells in vivo in rat liver. Phorbol myristate acetate (PMA) was infused into perfused rat liver which had been continuously infused with 2-methyl-6-[p-methoxyphenyl]-3,7-dihydroimidazo- [1,2-a]pyrazin-3-one (MCLA, a highly sensitive luminescence reagent for O2-) and the MCLA luminescence from the liver surface was detected with a sensitive photon counter. Under identical conditions, but without MCLA infusion, PMA and nitro blue tetrazolium were infused to verify generation of O2- by formation of formazan deposition. Based on MCLA luminescence and formazan deposition, both dependent on the O2- reaction, we have concluded that liver Kupffer cells generate O2- in vivo in response to stimuli such as PMA. Further, the generation of O2- by Kupffer cells may be by the same mechanism as displayed by macrophages.

Animals↗
PubMed1993

Analysis of enzyme-linked immunosorbent assay data for antigen quantitation using Lotus 1-2-3 software on a personal computer.

Absorbance data obtained in double-antibody sandwich enzyme-linked immunosorbent assay tests for quantitation of antigens are analyzed by a personal computer using the Lotus 1-2-3 software package. The sigmoid standard curve is processed by an iterative weighted regression analysis in the logit-log domain to obtain a linear dose-response relationship. A macro program is developed for quick calculation with easy operation, which is suited for routine laboratory tests in biomedical fields.

Antigens↗
PubMed1992

Genomic structure of human midkine (MK), a retinoic acid-responsive growth/differentiation factor.

Midkine (MK) is a product of a retinoic acid-responsive gene and a new heparin-binding growth/differentiation factor. The coding sequence of human MK was located on 1.5 kb DNA segment. The structure of the cloned human MK gene was determined and compared with that of the mouse gene. The coding sequence was divided into 4 exons, and each exon and exon-intron boundary was highly homologous to those of the mouse. Furthermore, 170 bases in the upstream region of the putative transcription initiation sites and 3 blocks of 200-350 bases in regions further upstream were highly conserved. These sequences are likely to be involved in developmentally regulated expression of MK.

Animals↗
PubMed1992

[Effects of continuous epidural infusion of local anesthetics on endocrine-metabolic responses to hysterectomy].

The plasma concentrations of glucose, insulin, epinephrine, norepinephrine and cortisol were measured in 18 women before, during and after abdominal hysterectomy. Nine patients received continuous epidural analgesia with intermittent injections of 10 ml of mepivacaine solution (intermittent group), and 9 others received epidural analgesia with continuous infusion of 10 ml.h-1 of 2% mepivacaine (continuous group). Plasma glucose and insulin concentrations remained unchanged during and after surgery in the two groups. Plasma epinephrine and norepinephrine concentrations increased after surgery, and cortisol concentration increased during and after surgery in the two groups. Plasma concentration of glucose during surgery was significantly lower in the continuous group than in the intermittent group. The methods of epidural administration of local anesthetics exert little influence on endocrine-metabolic responses to stress associated with lower abdominal surgery.

Adult↗
PubMed1991

A new family of heparin-binding factors: strong conservation of midkine (MK) sequences between the human and the mouse.

A retinoic acid responsive gene, MK, specifies for a heparin binding factor termed midkine (MK), which is the initial member of a new protein family involved in regulation of growth and differentiation. A cDNA clone of human MK was isolated from a fetal kidney cDNA library. Human MK mRNA was expressed in PA1 teratocarcinoma cells as well as in the kidney. Sequence analysis of the cDNA clone and of a part of the genomic clone yielded the predicted protein sequence of human MK. Human and mouse MK sequences are highly conserved: 87% of amino acids are identical and all amino acid changes are conservative except for an insertion. Comparison of MK and HB-GAM/pleiotrophin (another member of the family) from various species revealed sequences conserved in the family and those specific for each protein.

Adult↗
PubMed1991

Cytoskeleton in microridges of the oral mucosal epithelium in the carp, Cyprinus carpio.

Microridges produce a characteristic fingerprint-like pattern on the surface of fish oral mucosa. The cytoskeleton in these microridges was examined by immunofluorescence microscopy and transmission electron microscopy after detergent extraction and decoration with myosin subfragment 1. The effect of cytochalasin B on microridges was probed with scanning electron microscopy. Immunofluorescence microscopy revealed that actin filaments were present throughout the periphery of the epithelial cells and were especially localized beneath the free surface of the epithelium. In thin sections treated with Triton X-100, the majority of filaments in the microridges and their bases were found to be actin filaments and a plexus of keratin filaments that underlay the network of actin filaments. A part of the plexus of keratin filaments entered the microridges. After extraction with Triton X-100 and decoration with myosin subfragment 1, decorated actin filaments were found in the microridge cores, connected to the keratin filaments. The keratin filaments aggregated in the pattern of microridges and a few of them protruded into the microridges. Treatment with cytochalasin B caused microridges to disappear or to become thinner and lower or to change short or microvillus-like microridges. When most microridges disappeared, the surface of the superficial cells was prominently swollen, but the cell boundaries were fastened, and the microridges in the periphery were preserved. On the basis of these observations, the possible roles of actin and keratin filaments in the maintenance and the formation of microridges are discussed.

Actins↗
PubMed1991

Omental bleeding with spontaneously derotated torsion--a case report.

A case of omental torsion seen in a 16 year old male is reported herein. Abdominal pain in the right lower quadrant suddenly developed just after the patient twisted his waist and an emergency laparotomy revealed a hemorrhagic mass at the edge of the right omentum, which was excised. Histological examination of the resected specimen showed hemorrhage without any venous thrombosis or infarction, possibly suggestive of omental torsion with early spontaneous derotation. The patient was successfully treated as a case of omental torsion.

Abdominal Pain↗
PubMed1991

Highly sensitive chemiluminescence method for determining myeloperoxidase in human polymorphonuclear leukocytes.

Myeloperoxidase activity was assayed by a chemiluminescence method, using a cypridina luciferin analog as a chemiluminescence probe, after extraction from peripheral human polymorphonuclear leukocytes. The chemiluminescence method was based on the detection of 1O2 generated by myeloperoxidase-catalyzed HOBr formation followed by the interaction of HOBr with H2O2 at pH 4.5. With this method, myeloperoxidase in less than 100 polymorphonuclear leukocytes could be detected and myeloperoxidase in 10(6) polymorphonuclear leukocytes would be calculated to be 14.4 pmol. Eosinophil extract, which contains eosinophil peroxidase, catalyzed 1O2 generation to a great extent, compared with the polymorphonuclear leukocyte extract at pH 4.5. Myeloperoxidase activity in extract of neutrophil fraction could be greatly influenced by eosinophil contamination.

Deferoxamine↗
PubMed1991

Mechanism for the generation of superoxide anion and singlet oxygen during heme compound-catalyzed linoleic acid hydroperoxide decomposition.

Heme compound, hematin or cytochrome c, catalyzes the decomposition of 13-hydroperoxy linoleic acid yielding both O2- and 1O2 under aerobic conditions. No 1O2 is produced when hydrogen peroxide and cumene hydroperoxide are used as substrates. In these experiments, both O2- and 1O2 could be precisely detected by a chemiluminescence method using a cypridina luciferin analog, 2-methyl-6-(p-methoxyphenyl)-3,7-dihydroimidazo[1,2-a]pyrazin++ +-3-one, as a chemiluminescence probe, in the absence and presence of Cu-Zn superoxide dismutase in catalytic amounts. The reduction and oxidation cycle of ferric heme compound and the bimolecular reaction of peroxyl radicals are plausible reaction mechanisms for O2- and 1O2 production, respectively, in the systems studied.

Catalysis↗
PubMed1991

Production of 5-methyluridine by immobilized thermostable purine nucleoside phosphorylase and pyrimidine nucleoside phosphorylase from Bacillus stearothermophilus JTS 859.

5-Methyluridine was produced continuously from thymine and inosine by immobilized enzymes, which consisted of thermostable purine nucleoside phosphorylase and thermostable pyrimidine nucleoside phosphorylase obtained from Bacillus stearothermophilus JTS 859. The process was carried out in a column reactor at 60 degrees C for 17 d without any bacterial contamination under non-aseptical conditions. Half-lives of the activity of the immobilized enzymes were 47 d and 4.5 d at 60 degrees C and 70 degrees C, respectively, although half-life of the crude enzyme was only 14 h at 70 degrees C.

Bacterial Proteins↗