Search PubMed⌕ Search

Biomedical subjects

M Takeuchi

Publications and source records attributed to M Takeuchi.

At least 469 records · Page 26Linked to original sources
PubMed1996

[Successful surgical repair of acute DeBakey type I aortic dissection complicated by acute occlusion of the suprarenal abdominal aorta].

We reported a case of acute DeBakey type I aortic dissection presented with occlusion of the suprarenal abdominal aorta, who was successfully treated by simultaneous graft replacement of the ascending aorta and total aortic arch. The patient was a 68-year-old man who complained of chest pain and symptoms of acute arterial occlusion of bilateral lower extremities, and who had consciousness disturbance due to stroke caused by aortic dissection. He underwent simultaneous graft replacement of the ascending aorta and total aortic arch under selective cerebral perfusion during an emergent operation. For reconstruction of the arch vessels, we used three separate grafts that were connected to the aortic prosthesis before use. Although postoperative course was complicated by myonephropathic metabolic syndrome, the patient subsequently recovered and was discharged on foot. Early vascular reconstruction and appropriate management of reperfusion injury are extremely important in the setting of malperfusion phenomena complicating acute aortic dissection.

Aged↗
PubMed1996

[The present state of the 24-hour care system of our hospital and the examination of the significance and problems of the system].

The wishes of patients with terminal cancer are often not realized even if they indicate they want to die at home. We introduced a 24-hour visiting care system from November, 1994, with a view to making it possible for the patient who wants to to stay at home. As a result, the rate of the death at home increased; thus, the 24-hour visiting care system was significant for terminal care at home. On the other hand, from the viewpoint of a medical institution, the lack of sufficient cooperation with doctors and the increase of the burden on the staff were pointed out as problems to be resolved.

Adult↗
PubMed1996

[A case of neuroborreliosis with unilateral radiculoneuropathy and elevated serum antibodies for Borrelia garinii and Borrelia afzelii].

A 24-year-old male patient was admitted to our hospital because of dysesthesia and weakness of the right leg. Six weeks before admission he traveled to southern China. A week later he noticed multiple papules with itching on his right leg that were suspected to be insect bites. Four days later numbness of the right leg developed. Then he began to limp because of the leg weakness. Two weeks before admission severe pain in the right leg developed. On admission neurological examination revealed hypesthesia, muscle weakness and atrophy, areflexia, radicular pain and Lasègue sign of the right leg, and patchy hypesthesia of the left leg. The cranial nerves were intact, and meningeal signs were negative. Complete blood counts and serum biochemistry were unremarkable except for eosinophilia and mild elevation of IgE. A test for antinuclear antibody was positive. Cerebrospinal fluid was normal. Nerve conduction study and sural nerve biopsy showed multifocal severe axonopathy. Although antibody for Borrelia burgdorferi sensu stricto was negative, antibodies for B. garinii and for B. afzelii were positive in serum immunoblotting. Neurological symptoms improved after administration of intravenous ceftriaxon following oral doxycycline. In Japan, this is the second case of neuroborreliosis not due to B. burgdorferi sensu stricto. To test antibodies for B.garinii and for B. afzelii is recommended in patients with suspected neuroborreliosis.

Adult↗
PubMed1995

Role of antennary structure of N-linked sugar chains in renal handling of recombinant human erythropoietin.

To elucidate the role of the branched structure of sugar chains of human erythropoietin (EPO) in the expression of in vivo activity, the pharmacokinetic profile of a less active recombinant human EPO sample (EPO-bi) enriched with biantennary sugar chains was compared with that of a highly active control EPO sample enriched with tetraantennary sugar chains. After an intravenous injection in rats, 125I-EPO-bi disappeared from the plasma with 3.2 times greater total body clearance (Cltot) than control 125I-EPO. Whole-body autoradiography after 20 minutes of administration indicated that the overall distribution of radioactivity is similar, but 125I-EPO-bi showed a higher level of radioactivity in the kidneys than control 125I-EPO. Quantitative determination of radioactivity in the tissues also indicated that radioactivity of 125I-EPO-bi in the kidneys was two times higher than that of control 125I-EPO. The difference in plasma disappearance between 125I-EPO-bi and control 125I-EPO was not observed in bilaterally nephrectomized rats. The distribution of 125I-EPO-bi to bone marrow and spleen was similarly inhibited by simultaneous injection of excess amounts of either the nonlabeled EPO-bi or control EPO. These results indicate that the low in vivo biologic activity of EPO-bi results from rapid clearance from the systemic circulation by renal handling. Thus, the well-branched structure of the N-linked sugar chain of EPO is suggested to play an important role in maintaining its higher plasma level, which guarantees an effective transfer to target organs and stimulation of erythroid progenitor cells.

Animals↗
PubMed1995

Organization, regulatory sequences, and alternatively spliced transcripts of the mucosal addressin cell adhesion molecule-1 (MAdCAM-1) gene.

The mucosal addressin cell adhesion molecule-1 (MAdCAM-1) is expressed selectively at venular sites of lymphocyte extravasation into mucosal lymphoid tissues and lamina propria, where it directs local lymphocyte trafficking. MAdCAM-1 is a multifunctional type l transmembrane adhesion molecule comprising two distal lg domains involved in alpha 4 beta 7 integrin binding, a mucin-like region able to display L-selectin-binding carbohydrates, and a membrane-proximal lg domain homologous to lgA. We show in this work that the MAdCAM-1 gene is located on chromosome 10 and contains five exons. The signal peptide and each one of the three lg domains are encoded by a distinct exon, whereas the transmembrane, cytoplasmic tail, and 3'-untranslated region of MAdCAM-1 are combined on a single exon. The mucin-like region and the third lg domain are encoded together on exon 4. An alternatively spliced MAdCAM-1 mRNA is identified that lacks the mucin/lgA-homologous exon 4-encoded sequences. This short variant of MAdCAM-1 may be specialized to support alpha 4 beta 7-dependent adhesion strengthening, independent of carbohydrate-presenting function. Sequences 5' of the transcription start site include tandem nuclear factor-kappa B sites; AP-1, AP-2, and signal peptide-1 binding sites; and an estrogen response element. Our findings reinforce the correspondence between the multidomain structure and versatile functions of this vascular addressin, and suggest an additional level of regulation of carbohydrate-presenting capability, and thus of its importance in lectin-mediated vs alpha 4 beta 7-dependent adhesive events in lymphocyte trafficking.

Alternative Splicing↗
PubMed1995

Alterations in superoxide dismutase and catalase in Fusarium oxysporum during starvation-induced differentiation.

Vegetative hyphae of Fusarium oxysporum differentiate into chlamydospore by triggering with carbon-starvation. The current changes in the cellular detoxifying defenses against superoxide and hydrogen peroxide: superoxide dismutase (SOD) and catalase, were examined. Although there was a little change in catalase, a dramatic change in SOD was observed during the differentiation. In vegetative hyphae of F. oxysporum f. sp. raphani, three isozymes of SOD, all of which were not inhibited by hydrogen peroxide and cyanide, were present whereas in chlamydospore an isoenzyme, which was inhibited by hydrogen peroxide but not by cyanide, was present. Thus, as differentiation proceeded, Mn-type SOD disappeared and an Fe-type SOD appeared. The results suggest that the Fe-type SOD is specifically expressed during chlamydospore formation and that active intermediates of oxygen and/or its scavenging enzymes participate in the differentiation of Fusarium oxysporum.

Anaerobiosis↗
PubMed1995

Induction of NCAM expression in mouse olfactory keratin-positive basal cells in vitro.

The expression of neural cell adhesion molecule (NCAM) by olfactory keratin+ basal cells was investigated in vitro. In primary cultures from embryonic day 14.5 or newborn mouse olfactory epithelium (OE), flat keratin+ basal cells were negative for NCAM-immunostaining. Transforming-growth factor-beta 1, beta 2 (TGF-beta 1, beta 2) or a high concentration of Ca2+ induced these cells to express NCAM. We obtained a cell line, designated DBC1.2, from embryonic day 14.5 mouse OE. All DBC1.2 cells were positive for keratin-immunostaining, whereas nearly all cells were negative for NCAM-immunostaining. Therefore, DBC1.2 cells seemed to derive from dark basal cells. DBC1.2 cells were also induced to express NCAM by the treatment with TGF-beta s or a high Ca2+ concentration. Western blotting revealed that the components of the NCAM expressed by DBC1.2 were 120 and 140 kDa, but not 180 kDa, isoforms. Since NCAM is the cell adhesion molecule mainly expressed in nervous tissues, these results suggest a cell lineage relationship or interactions between olfactory keratin+ basal cells and olfactory sensory neurons.

Aging↗
PubMed1995

Effects of leukemia inhibitory factor on the differentiation of astrocyte progenitor cells from embryonic mouse cerebral hemispheres.

The effects of leukemia inhibitory factor (LIF) on the differentiation and proliferation of astrocyte progenitor cells in an enriched culture were studied. The astrocyte progenitor cells obtained from embryonic mouse cerebral hemispheres were enriched by subculturing twice in serum-free medium containing epidermal growth factor (EGF). They exhibited a flat, non-process-bearing morphology and were negative for glial fibrillary acidic protein (GFAP), a specific marker for astrocytes. Culture of the cells with LIF resulted in the expression of GFAP and in the inhibition of growth. These results suggest that LIF promotes the differentiation of astrocyte progenitor cells.

Animals↗
PubMed1995

p93dis1, which is required for sister chromatid separation, is a novel microtubule and spindle pole body-associating protein phosphorylated at the Cdc2 target sites.

Fission yeast cold-sensitive (cs) dis1 mutants are defective in sister chromatid separation. The dis1+ gene was isolated by chromosome walking. The null mutant showed the same phenotype as that of cs mutants. The dis1+ gene product was identified as a novel 93-kD protein, and its localization was determined by use of anti-dis1 antibodies and green fluorescent protein (GFP) tagged to the carboxyl end of p93dis1. The tagged p93dis1 in living cells localizes along cytoplasmic microtubule arrays in interphase and the elongating anaphase spindle in mitosis, but association with the short metaphase spindle microtubules is strikingly reduced. In the spindle, the tagged p93dis1 is enriched at the spindle pole bodies (SPBs). Time-lapse video images of single cells support the localization shift of p93dis1 to the SPBs in metaphase and spindle microtubules in anaphase. The carboxy-terminal fragment, which is essential for Dis1 function, accumulates around the mitotic SPB. We propose that these localization shifts of p93dis1 in mitosis facilitates sister chromatid separation by affecting SPB and anaphase spindle function.

Amino Acid Sequence↗
PubMed1995

Tamoxifen directly stimulates the mineralization of human osteoblast-like osteosarcoma cells through a pathway independent of estrogen response element.

Tamoxifen, an estrogen antagonist, stimulated the mineralization of osteoblasts in vitro in a dose-dependent manner in the presence of inorganic phosphate. The mechanism of mineralization by tamoxifen was different from that by 1 alpha, 25-dihydroxyvitamin D3. In addition, tamoxifen did not activate estrogen-response-element-mediated transcription in osteoblasts. These findings suggest that tamoxifen directly stimulates the mineralization of osteoblasts through a pathway independent of the conventional estrogen-response-element-mediated gene expression.

Alkaline Phosphatase↗