Biomedical subjects

K Hatano

Publications and source records attributed to K Hatano.

At least 19 recordsLinked to original sources

PubMed2002

[Strategy for preventing recurrence after video-assisted thoracoscopic surgery for spontaneous pneumothorax; efficacy of talc pleurodesis and absorbable mesh covering].

Video-assisted thoracoscopic surgery (VATS) has been widely used in the treatment of spontaneous pneumothorax. The unexpectedly high increase of the recurrence rate is the most important problem. We examined the interaction between recurrence, clinical features and patient's backgrounds. The main causes of recurrence were oversight of bullae and the emphysematous changes at the periphery of the site where an autosuture device was used. 90% of the recurrence occurred in the patients with type III small diffuse bullae. Introduction of the regional talc pleurodesis and covering stapled line with absorbable mesh were extremely useful to lower the recurrence rate after VATS for spontaneous pneumothorax.

Absorbable Implants↗

PubMed2001

T cell responses to major membrane protein II (MMP II) of Mycobacterium leprae are restricted by HLA-DR molecules in patients with leprosy.

Major membrane protein II (MMP II) of Mycobacterium leprae (M. leprae) is a 22kDa protein inducing humoral immune response in leprosy patients. MMP II-specific bulk T cell lines were established from leprosy patients to determine major T cell epitopes in MMP II and to evaluate lymphokine production induced by MMP II. These bulk T cell lines reacted to one or more peptides in the locus of amino acid residues from 23 to 109 of MMP II. The proliferative responses of all T cell lines were mainly inhibited by the addition of anti-DRB1 mAb. Many bulk T cell lines induced IFN-gamma, IL-5, but not IL-4. However, it was not possible to distinguish the LL or TT types of leprosy based on the pattern of T cell epitopes and the lymphokine productivity in the responses against MMP II. Thus, it appears that T cell response to MMP II is restricted by the HLA-DRB1 molecule, but not by DQ and DP molecules, which results in the induction of IFN-gamma production.

Amino Acid Sequence↗

PubMed2001

Age-related changes of dopamine D1-like and D2-like receptor binding in the F344/N rat striatum revealed by positron emission tomography and in vitro receptor autoradiography.

To clarify age-related changes in dopamine D1-like and D2-like receptor binding in the striatum, positron emission tomography (PET) and in vitro receptor autoradiography (in vitro ARG) were performed using F344/N rats of various ages (6, 12, 18, and 24 months). In the PET study, [11C]SCH23390 and [11C]raclopride were used to image dopamine D1-like receptors and dopamine D2-like receptors, respectively, while [3H]SCH23390 and [3H]raclopride were used for the in vitro ARG study. With PET, we calculated the binding potential (= k3/k4, Bmax/Kd) of [11C]SCH23390 and [11C]raclopride in the striatum according to the curve fitting (CF) and the Logan plot (LP) methods. The binding potential of [11C]SCH23390 in the striatum demonstrated significant decrease as a function of age (max. decrease -26%) by the LP method, while this was not observed in the data analyzed by the CF method. In contrast, the binding potential of [11C]raclopride in the striatum decreased significantly with age by both the CF (max. decrease -28%) and the LP (max. decrease -36%) methods. However, no significant difference by either method was observed in rats between 6 and 12 months old using either ligand. In the in vitro ARG study, the specific binding (fmol/mg tissue) of [3H]SCH23390 and [3H]raclopride in the striatum were determined. Both [3H]SCH23390 and [3H]raclopride binding declined considerably with age as noted by comparing 12, 18, and 24-month-old rats against those 6 months old (max. decrease -29% and -31%, respectively). The substantial difference in binding shown in 12-month-olds in comparison with 6-month-olds using either ligand with in vitro ARG was in contrast with the PET results. These distinctions between the PET and the in vitro ARG studies may be attributed to the receptor microenvironment created under these experimental conditions. The results indicate that PET with LP analysis is useful in obtaining age-related changes of D1-like and D2-like receptor binding in the striatum of living rats.

Aging↗

PubMed2001

Lung interleukin-4 gene expression in a murine model of bleomycin-induced pulmonary fibrosis.

Interleukin-4 (IL-4) is known to activate mononuclear cells as well as fibroblasts, all of which are important in the pathogenesis of pulmonary fibrosis. To investigate the potential role of this cytokine, lung IL-4 expression was examined in a murine model of bleomycin-induced pulmonary fibrosis. Lung fibrosis was induced in CBA/J mice by endotracheal injection of bleomycin on day 0. On selected days after treatment, lungs were harvested for reverse transcriptase polymerase chain reaction (RT-PCR), Northern, in-situ hybridization and immunohistochemical analyses. RT-PCR and Northern analyses revealed significant increases in lung IL-4 mRNA content between days 3 and 14 after induction of lung injury, which decreased toward control level after day 21. Both in-situ hybridization and immunohistochemistry showed low or undetectable IL-4 expression in control lungs and in injured lungs before day 3 after bleomycin injection. There was however elevated expression in mononuclear cells and macrophages between days 3 and 14, localized to areas of active fibrosis. These results demonstrate that IL-4 is upregulated significantly in this model. They suggest a potential role for this cytokine in pulmonary fibrosis, perhaps via its ability to stimulate and amplify the inflammatory response, stimulate collagen synthesis in fibroblasts, and thus promote the progression to fibrosis and end stage lung disease.

Animals↗

PubMed2001

Activation reduction in anterior temporal cortices during repeated recognition of faces of personal acquaintances.

Repeated recognition of the face of a familiar individual is known to show semantic repetition priming effect. In this study, normal subjects were repeatedly presented faces of their colleagues, and the effect of repetition on the regional cerebral blood flow change was measured using positron emission tomography. They repeated a set of three tasks: the familiar-face detection (F) task, the facial direction discrimination (D) task, and the perceptual control (C) task. During five repetitions of the F task, familiar faces were presented six times from different views in a pseudorandom order. Activation reduction through the repetition of the F tasks was observed in the bilateral anterior (anterolateral to the polar region) temporal cortices which are suggested to be involved in the access to the long-term memory concerning people. The bilateral amygdala, the hypothalamus, and the medial frontal cortices, were constantly activated during the F tasks, and considered to be associated with the behavioral significance of the presented familiar faces. Constant activation was also observed in the bilateral occipitotemporal regions and fusiform gyri and the right medial temporal regions during perception of the faces, and in the left medial temporal regions during the facial familiarity detection task, which are consistent with the results of previous functional brain imaging studies. The results have provided further information about the functional segregation of the anterior temporal regions in face recognition and long-term memory.

Adult↗

PubMed2001

Neural substrates for recognition of familiar voices: a PET study.

Identification of familiar people is essential in our social life. We can identify familiar people by hearing their voices as well as by viewing their faces. By measuring regional cerebral blood flow (rCBF) by positron emission tomography (PET), we identified neural substrates for the recognition of familiar voices. The brain activity during discrimination of voices of the subjects' associates and friends from those of unfamiliar people was compared with that during an analogous discrimination of their own voice from unfamiliar voices as well as during vowel discrimination. The left frontal pole, right temporal pole, right entorhinal cortex, and left precuneus were activated to a greater extent during discrimination of familiar voice than during control discriminations, suggesting that these brain regions are involved in the recognition of familiar voices. Furthermore, the adjusted values of rCBF in the left frontal pole and right temporal pole correlated with the number of subjects' correct identification of familiar voices. The present results suggest that these two regions are coactively associated with matching the currently heard voice to familiar voices in one's memory.

Adult↗

PubMed2001

Different neural systems for recognizing plants, animals, and artifacts.

The purpose of this study was to investigate functional organization in the human brain involved in the representation of knowledge regarding plants. We measured the brain activity of eight male volunteers during the recognition of visual stimuli representing plants, animals and artifacts, using positron emission tomography. The participants were presented with and were required to name silently two different images each of 15 entities belonging to three ontological categories, and 30 series of four to six digits. Marked increases in regional cerebral blood flow were found in the hippocampus and the parahippocampal areas bilaterally and the right lateral occipital cortex during the silent naming of all three categories, compared with that during the silent reading of digits. The right lateral occipital cortex was specifically activated in association with the naming of plants, and the right fusiform cortex was specifically activated in association with the naming of animals. In addition, the right temporo-occipital cortex was activated only during animals and plants, not artifacts. Our results indicate that there were a few characteristic activations for the different categories, and that entities belonging to the different categories are not necessarily represented in different locations of the brain.

Cerebral Cortex↗

PubMed2001

Synthesis and in vivo evaluation of [11C]methyl-Ro 64-6198 as an ORL1 receptor imaging agent.

(1S,3aS)-8-(2,3,3a,4,5,6-Hexahydro-1H-phenalen-1-yl)-3-N-[11C]methyl-1-phenyl-1,3,8-triaza-spiro[4.5]decan-4-one ([11C]methyl-Ro 64-6198), a N-methylated analog of Ro 64-6198, was synthesized and evaluated as a potential radiopharmaceutical for investigating brain nociceptin/orphanin FQ receptors (ORL1 receptors) by positron emission tomography. A racemate of methyl-Ro 64-6198, Ro 66-7931, showed a high affinity and selectivity for the ORL1 receptor in vitro. An in vivo distribution study in mice demonstrated moderate brain uptake, however, only slight difference was observed among brain regions. Furthermore, pretreating with nociceptin or Ro 66-7931 did not affect the accumulation. Therefore, despite its high affinity, [11C]methyl-Ro 64-6198 does not appear to be a suitable tracer for in vivo ORL1 receptor imaging studies.

Animals↗

PubMed2001

Structural analysis of the lipopolysaccharide core of a rough, cystic fibrosis isolate of Pseudomonas aeruginosa.

Lipopolysaccharide (LPS) expressed by isolates of Pseudomonas aeruginosa from cystic fibrosis patients lacks the O-polysaccharide chain but the degree to which the rest of the molecule changes has not been determined. We analyzed, for the first time, the core structure of an LPS from a rough, cystic fibrosis isolate of P. aeruginosa. The products of mild acid hydrolysis and strong alkaline degradation of the LPS were studied by ESI MS, MALDI MS, and NMR spectroscopy. The following structure was determined for the highest-phosphorylated core-lipid A backbone oligosaccharide isolated after alkaline deacylation of the LPS: [structure: see text] where Kdo and Hep are 3-deoxy-D-manno-octulosonic acid and L-glycero-D-manno-heptose, respectively; all sugars are in the pyranose form and have the D configuration unless stated otherwise. The outer core region occurs as two isomeric glycoforms differing in the position of rhamnose (Rha). The inner core region carries four phosphorylation sites at two Hep residues, HepI being predominantly bisphosphorylated and HepII monophosphorylated. In the intact LPS, both Hep residues carry monophosphate and diphosphate groups in nonstoichiometric quantities, GalN is N-acylated by an L-alanyl group, HepII is 7-O-carbamoylated, and the outer core region is nonstoichiometrically O-acetylated at four sites. Therefore, the switch to the LPS-rough phenotype in cystic fibrosis isolates of P. aeruginosa is not accompanied by losses of core monosaccharide, phosphate or acyl components. The exact positions of the O-acetyl groups and the role of the previously undescribed O-acetylation in the LPS core of P. aeruginosa remain to be determined.

Carbohydrate Conformation↗

PubMed2001

Revival of the genus Lentzea and proposal for Lechevalieria gen. nov.

The genus Saccharothrix is phylogenetically heterogeneous on the basis of analysis of almost complete 16S rDNA sequences. An evaluation of chemotaxonomic, morphological and physiological properties in the light of the molecular phylogeny data revealed that several species are misclassified. Saccharothrix aerocolonigenes NRRL B-3298T and Saccharothrix flava NRRL B-16131T constitute a lineage distinct from Saccharothrix and separate from Lentzea. The genus Lechevalieria gen. nov. is proposed for these species. Lechevalieria aerocolonigenes comb. nov. is the type species and S. flava is transferred as Lechevalieria flava comb. nov. Although Lentzea albidocapillata, the type species of the genus Lentzea, was transferred recently to the genus Saccharothrix, the revival of Lentzea is clearly supported by molecular phylogenetic and chemotaxonomic data. The description of the revived genus is emended to include galactose, mannose and traces of ribose as diagnostic whole-cell sugars and MK-9(H4) as the principal menaquinone and elimination of tuberculostearic acid as a diagnostic component in the fatty acid profile. Saccharothrix waywayandensis NRRL B-16159T, S. aerocolonigenes NRRL B-16137 and 'Asiosporangium albidum' IFO 16102 are members of the amended genus Lentzea on the basis of phylogenetic and chemotaxonomic properties. S. waywayandensis is transferred to Lentzea as Lentzea waywayandensis comb. nov., while the new species Lentzea californiensis sp. nov. and Lentzea albida sp. nov. are described for S. aerocolonigenes NRRL B-16137 and 'A. albidum' IFO 16102, respectively. Nucleotide signatures in the 16S rDNA sequences are defined that are diagnostic for the genera Lechevalieria, Lentzea and Saccharothrix.

Actinomycetales↗

PubMed2001

Agromyces luteolus sp. nov., Agromyces rhizospherae sp. nov. and Agromyces bracchium sp. nov., from the mangrove rhizosphere.

The taxonomic positions of four strains isolated from the mangrove rhizosphere were studied by a polyphasic approach using phenotypic, chemotaxonomic and genetic methods. The four isolates contain 2,4-diaminobutyric acid in their peptidoglycan, and rhamnose as the major cell wall sugar. The predominant menaquinones are MK-12 and MK-11. The predominant cellular fatty acids are iso-C16:0, anteiso-C15:0 and/or anteiso-C17:0. The G+C content of the DNA ranges from 70.0 to 73.3 mol%. The four strains formed a coherent cluster with Agromyces species in a phylogenetic inference based on 16S rDNA sequences. Interestingly, the four isolates grew well in the presence of 5% NaCl. The differences in some phenotypic and chemotaxonomic characteristics, 16S rDNA sequence similarity data and DNA-DNA relatedness data indicate that the four isolates represent three new species in the genus Agromyces, for which are proposed the names Agromyces luteolus for strain 8T (IFO 16235T = VKM Ac-2085T), Agromyces bracchium for strain 65T (IFO 16238T = VKM Ac-2088T) and Agromyces rhizospherae for strains 14T (IFO 16236T = VKM Ac-2086T) and 58(5) (IFO 16237 = VKM Ac-2087).

Actinomycetales↗

PubMed2001

A new genus of the order Actinomycetales, Virgosporangium gen. nov., with descriptions of Virgosporangium ochraceum sp. nov. and Virgosporangium aurantiacum sp. nov.

Four motile spored strains were isolated from soil samples collected in Japan. The cultures formed long, narrow sporangia on short sporangiophores directly on the substrate mycelium. The sporangia develop singly or in clusters above the surface of the substrate. Each sporangium contains a single row of six or more motile spores. Glutamic acid, glucosamine, glycine, alanine and 3-OH-diaminopimelic acid are present in the cell wall; the whole-cell sugars are 3-O-methylmannose, rhamnose, mannose, arabinose, galactose, xylose and glucose; and the predominant menaquinones are 10(H4), 10(H6) and 10(H8). The diagnostic phospholipid is phosphatidylethanolamine. The acyl type of the muramic acid is glycolyl. The G+C content is 71 mol%. Mycolic acids are absent. The chemotaxonomic data indicate that these strains belong to the family Micromonosporaceae. Analysis of 165 rDNA sequences suggested that these organisms fall into a distinct clade within the family Micromonosporaceae for which a new genus, Virgosporangium gen. nov., is proposed containing the species Virgosporangium ochraceum sp. nov. (strains YU655-43T, YU793-41 and YU794-41) and Virgosporangium aurantiacum sp. nov. (strain YU438-5T).

DNA, Ribosomal↗

PubMed2001

Phylogenetic analysis of the genus Actinoplanes and transfer of Actinoplanes minutisporangius Ruan et al. 1986 and 'Actinoplanes aurantiacus' to Cryptosporangium minutisporangium comb. nov. and Cryptosporangium aurantiacum sp. nov.

The phylogenetic structure of the genus Actinoplanes was determined by comparative 16S rDNA sequence analysis of the type strains of all validly described Actinoplanes species and other strains of Actinoplanes. Actinoplanes minutisporangius IFO 15962T and 'Actinoplanes aurantiacus' IFO 13967 were placed outside the family Micromonosporaceae and appeared to be closely related to the genus Cryptosporangium. On the basis of their morphological and chemotaxonomic characteristics and phylogenetic analysis, these strains were reclassified into the genus Cryptosporangium. DNA-DNA hybridization revealed that these strains differed from the species previously described in this genus. Therefore, the transfer is proposed of Actinoplanes minutisporangius Ruan et al. 1986 and 'Actinoplanes aurantiacus' IFO 13967 to the genus Cryptosporangium as Cryptosporangium minutisporangium comb. nov. and Cryptosporangium aurantiacum sp. nov.

Actinomycetales↗

PubMed2001

Clustered cancer cells show a distinct adhesion behavior from single cell form under physiological shear conditions.

It remains a question whether hematogeneous metastasis arises from a single cancer cell attached to the local endothelium or from a cluster of cancer cells trapped in the vascular bed in the target organ. Adhesive interaction of the single cell form and the clustered form of cancer cells was examined under flow conditions, using two subclones of mouse colon adenocarcinoma Colon 26. A subclone NL17, but not NL14, formed many clusters composed of tumor cells and platelets just after the addition of platelet rich plasma (PRP). Under the shear of 1.0 dyn/cm3, the clustered form of NL17 tethered on laminin or mouse endothelial cell line in hepatic sinusoids (HSE) more frequently than the single cell form of NL17 and NL14. However, all of the clusters showed only transient attachment and never underwent stable arrest on coated laminin, while the single cell form of NL14 and NL17 underwent immediate arrest under shear conditions. On HSE stimulated with TNF-alpha, a small number of NL17 clusters made stable adhesion, although all the clusters detached if the shear stress was increased above 4.0 dyn/cm2. In contrast, the single form of arrested NL17 as well as NL14 remained adherent even at shear of 8.0 dyn/cm2. Compared with single cell, binding of cancer cell clusters to laminin and HSE showed lower resistance to shear stress, although they had adhesive interactions more frequently in flow condition. Since NL17 cells form significantly more metastases by intravenous injection in vivo, our data suggest that "stable adhesion" observed in our flow assay system is not always a prerequisite for clustered cancer cells to develop into metastatic lesions.

Adenocarcinoma↗

PubMed2000

Passive and active recognition of one's own face.

Facial identity recognition has been studied mainly with explicit discrimination requirement and faces of social figures in previous human brain imaging studies. We performed a PET activation study with normal volunteers in facial identity recognition tasks using the subject's own face as visual stimulus. Three tasks were designed so that the activation of the visual representation of the face and the effect of sustained attention to the representation could be separately examined: a control-face recognition task (C), a passive own-face recognition task (no explicit discrimination was required) (P), and an active own-face recognition task (explicit discrimination was required) (A). Increased skin conductance responses during recognition of own face were seen in both task P and task A, suggesting the occurrence of psychophysiological changes during recognition of one's own face. The left fusiform gyrus, the right supramarginal gyrus, the left putamen, and the right hypothalamus were activated in tasks P and A compared with task C. The left fusiform gyrus and the right supramarginal gyrus are considered to be involved in the representation of one's own face. The activation in the right supramarginal gyrus may be associated with the representation of one's own face as a part of one's own body. The prefrontal cortices, the right anterior cingulate, the right presupplementary motor area, and the left insula were specifically activated during task A compared with tasks C and P, indicating that these regions may be involved in the sustained attention to the representation of one's own face.

Adult↗

PubMed2000

Extrastriatal mean regional uptake of fluorine-18-FDOPA in the normal aged brain--an approach using MRI-aided spatial normalization.

The aim of this study was to define the mean regional 6-[(18)F]fluoro-l-dopa (FDOPA) uptake rate constant (K(i)) values in the striatal and extrastriatal regions of the brain of normal subjects using magnetic resonance imaging (MRI)-aided spatial normalization of the FDOPA K(i) image and using automatic region of interest (ROI) analysis. Dynamic three-dimensional FDOPA positron emission tomography (PET) and three-dimensional magnetic resonance (MR) images were acquired in 13 aged normal subjects. The FDOPA add image and the K(i) image of each subject were transformed into standard stereotactic space with the aid of individual coregistered MR image. The mean regional K(i) values of the striatal and extrastriatal regions before normalization were compared with the respective values after normalization. Then automatic ROI analysis was performed on the MRI-aided spatially normalized K(i) images of the 13 normal subjects. The K(i) values on original images and those on spatially normalized images were in good agreement, indicating that the spatial normalization technique did not change the regional K(i) values appreciably. Automatic ROI analysis of the spatially normalized FDOPA K(i) images of the normal subjects, showed high K(i) values in ventral and dorsal regions of the midbrain, amygdala, hippocampus, and medial prefrontal cortex, in addition to caudate nucleus and putamen, which correspond to the dopaminergic projections in the brain. Spatial normalization technique helped to establish a database of FDOPA K(i) images of normal subjects and high K(i) values were observed widely besides striatal regions corresponding to the dopaminergic projections in the brain.

Aged↗

PubMed2000

Relation between thymidylate synthase expression and survival in colon carcinoma, and determination of appropriate application of 5-fluorouracil by immunohistochemical method.

BACKGROUND: Thymidylate synthase (TS) is regarded as a parameter of 5-fluorouracil (5-FU) chemosensitivity for colorectal carcinoma. Recent researchers indicate that the chemosensitivity of 5-FU for colorectal carcinoma with low expression of TS is better than tumors with high expression of TS. But the relation between TS expression and overall survival of curatively resected colorectal cancer patients has been less studied. METHODS: Specimens of curatively resected colon carcinoma from 148 patients were included in this study. TS expression in the tumor was assessed by immunohistochemical staining technique, and the patients were categorized into TS-(+) and TS-(-) groups. First, the relation between TS expression and survival of patients was examined. Next, for each group, we compared survival between the chemotherapy-(+) and the chemotherapy-(-) subgroup. RESULTS: Overall survival was significantly better in the TS-(-) group (n = 107) than in the TS-(+) group (n = 41) (P = .0003). In the TS-(-) group, there was little difference between the chemotherapy-(+) and the chemotherapy-(-) subgroup. In the TS-(+) group, the survival of the chemotherapy-(+) subgroup was significantly better than the chemotherapy-(-) subgroup (P = .0439). CONCLUSIONS: TS, itself, may be a prognostic factor for colon carcinoma; and 5-FU adjuvant chemotherapy may be appropriate for colon carcinoma with high expression of TS.

Antimetabolites, Antineoplastic↗

PubMed2000

Psoas abscess complicating Crohn's disease: report of a case.

We describe herein the case of a psoas abscess complicating Crohn's disease, and present a review of the literature on this unusual disease entity. A 22-year-old Japanese man with a 5-year history of Crohn's ileocolitis presented with right lower abdominal and hip pain, and a diagnosis of right psoas abscess was subsequently made by abdominal computed tomography (CT). Following the administration of antibiotics and CT-guided percutaneous drainage of the abscess, the patient's symptoms temporarily improved; however, 2 weeks later, the abscess cavity was found to have extended around the periarticular tissue of the right hip joint. To prevent the development of septic arthritis of the hip joint, surgical drainage of the abscess cavity and ileocecal resection were immediately performed, after which the patient's condition greatly improved. The resected specimen showed Crohn's ileocolitis with an external fistula in the terminal ileum which was considered to have caused the psoas abscess. Since psoas abscess in Crohn's disease can result in serious complications such as septic arthritis of the hip joint if left untreated, aggressive treatment should be initiated without delay.

Adult↗