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Biomedical subjects

K Fukushima

Publications and source records attributed to K Fukushima.

At least 343 records · Page 19Linked to original sources

Bacitracin production by a new strain of Bacillus subtilis. Extraction, purification, and characterization.

A new strain of Bacillus subtilis C 126 was isolated from sugar cane fermentation and produced an antibiotic that inhibited the growth of Micrococcus flavus. The production of the antibiotic in culture medium followed to extraction with n-butanol, thin layer chromatography, and microbiological tests indicated that a polypeptide antibiotic was produced. The fraction obtained by Sephadex G-25 column and analyzed by HPLC indicated that bacitracin complex was produced.

1-Butanol↗

Responses of floccular Purkinje cells to sinusoidal vertical rotation and effects of muscimol infusion into the flocculus in alert cats.

To understand how the flocculus is involved in the integration process in the vertical VOR, we examined the responses of floccular Purkinje cells during whole-body rotation in many vertical and horizontal planes in alert cats. The great majority of cells that responded to pitch rotation received excitation from the contralateral posterior canal, whereas the minority received excitation from the anterior canal, either on the ipsilateral or contralateral side; 35% of these vertical canal responding cells received convergent inputs, either from the ipsilateral or contralateral horizontal canal. After infusion of a GABA agonist (muscimol) into the area where many posterior canal responding Purkinje cells were recorded, the downward VOR induced by nose-up pitch was selectively impaired at low stimulus frequencies, together with an impairment of gaze holding after downward saccades. These results indicate a crucial role for posterior canal responding floccular Purkinje cells in generating downward eye position signals. Since the flocculus inhibits VOR interneurons related to the anterior and horizontal canals but not the posterior canal (Ito, 1984), our results suggest the possibility that posterior canal responding floccular Purkinje cells may form a transfloccular inhibitory pathway to anterior canal related VOR interneurons. This pathway may facilitate the positive feedback effect in the vestibular commissural inhibitory pathway between the co-planar vertical canals for the posterior canal signal, and may thereby be specifically involved in integration in the vertical VOR.

Animals↗

Processing inhibition of N-linked sugar chains associated with induction of Fc receptor-mediated phagocytosis in the mouse monocytoid cells.

The concanavalin A staining of cellular glycoproteins and the direct analysis of their sugar chains released by hydrazinolysis revealed that the processing of N-linked sugar chains of some glycoproteins is suppressed by exposure of mouse monocytoid cells P388D1 to dimethyl sulphoxide, which can induce Fc receptor-mediated phagocytosis. To elucidate the significance of altered glycosylation in inducing phagocytosis, the effects of exposure of the cells to processing inhibitors (swainsonine and castanospermine) were examined and it was found that the cells are induced to acquire an ability to ingest IgG-coated sheep red blood cells, depending on the dose of the inhibitors and incubation time. Analysis of the N-linked sugar chains liberated from cellular glycoproteins by hydrazinolysis confirmed that the processing of the sugar chains is suppressed by the two inhibitors as expected. Since no significant alteration was induced in protein synthesis and DNA synthesis after exposure to the inhibitors, it is suggested that the altered glycosylation of cellular glycoproteins may have some direct role in the induction of Fc receptor-mediated phagocytosis. The inhibitors did not affect the binding of the IgG-coated red blood cells to Fc receptors on the cells, non-specific phagocytosis of latex beads, and the contents of lysosomal enzymes, beta-glucuronidase and acid phosphatase. These results suggest that the glycosylation status of cellular glycoproteins influences some specific processes involved in the ingestion of the ligands bound to Fc receptors.

Animals↗

Responses of plasma vasoactive intestinal polypeptide to methacholine and exercise loading in children and adolescents with bronchial asthma.

Responses of plasma vasoactive intestinal polypeptide (VIP) to methacholine inhalation and to exercise loading were studied in asthmatic patients to clarify a significant role of the peptide. The mean of basal VIP in asthmatics was not significantly different from the normals. The levels were increased after FEV (1.0) (forced expiratory volume in a second) decreased to 80% of the baseline following methacholine inhalation and were returned to values similar to the baseline when FEV (1.0) recovered to 100%. Thirty minutes after the exercise, mean VIP was significantly lower in patients with the lowest FEV (1.0). These results suggest that VIPergic system contributes, at least partly, to relax constricted bronchioles in some patients with bronchial asthma.

Adolescent↗

Contribution of rib cage and abdominal movement to ventilation for successful weaning from mechanical ventilation.

In order to test the hypothesis whether the breathing pattern is helpful in predicting weaning outcome in patients being weaned from mechanical ventilation, 38 patients who underwent operation for esophageal cancer were evaluated at weaning from mechanical ventilation (19 unsuccessful weanings, group U, and 19 successful weanings in age-matched patients, group S). Since all patients initially fulfilled our weaning criteria, ventilatory parameters such as tidal volume, respiratory frequency, minute ventilation, and arterial blood gas analysis showed no significant differences between the groups. The breathing pattern was registered quantitatively by means of respiratory inductive plethysmography at 3 cmH2O (0.3 kPa) of CPAP prior to weaning. The contribution of rib cage movement to tidal volume (%RC) was significantly greater in group U than in group S (P < 0.05). Indeed, 84% of the patients in group S showed %RC less than 50%, compared to only 16% of the patients in group U (P < 0.05). The results suggest that the breathing pattern is one important factor in predicting the outcome of weaning in patients after thoraco-abdominal surgery. Diaphragmatic fatigue is suspected to be the mechanism for the increase in the RC component in patients with unsuccessful weaning outcome.

Abdomen↗

Drop attacks and epileptic syndromes.

1. In addition to 4 types of drop attacks previously described by Ikeno et al., we could ascertain the falls of the myoclonic-tonic type in genuine drop attacks. The genuine drop attacks were seen in Lennox-Gastaut syndrome, epilepsy with myoclonic-astatic seizures and other symptomatic generalized epilepsies, and never in partial epilepsies. 2. None of the patients with partial epilepsy revealed genuine drop attacks as defined. Their drop attacks were slower (i.e. the falls were completed in more than 1 sec.). 3. In the 15 patients with Lennox-Gastaut syndrome, the drop attacks disappeared in 8 patients, and decreased in severity and frequency in 3 patients. Namely, the intractability of drop attacks in two-thirds of the children decreased as the patients grew older. This finding must be taken into consideration when patients with drop attacks are considered for surgical treatment of their epilepsy.

Adolescent↗

EBER-1 expression in thymic carcinoma.

The Epstein-Barr virus-encoded small nuclear RNA, EBER-1, has been shown to be a suitable target for the in situ hybridization detection of EBV in routinely processed tissue specimens. We evaluated the presence of EBV in thymic carcinoma and invasive thymoma using EBER-1 in situ hybridization on formalin-fixed paraffin-embedded tissue sections. EBER-1 expression was demonstrated in a case of lymphoepithelioma-like thymic carcinoma, but was not detectable in other thymic carcinomas including six squamous cell carcinomas, a clear cell carcinoma and seven invasive thymomas. As reported in three previous cases of EBV-associated thymic carcinoma, lymphoepithelioma-like thymic carcinoma was shown to be closely associated with EBV in our series.

Adolescent↗

Production, characterization, and application of monoclonal antibodies which distinguish three glucosyltransferases from Streptococcus mutans.

Thirty-three murine monoclonal antibodies (MAbs) against the three glucosyltransferases (GTFs) (GTF-I, -SI, and -S) from Streptococcus mutans were obtained by the fusion of murine myeloma cells (P3X63-Ag8-U1) with spleen cells of BALB/c mice immunized with pure GTF-S or partially purified GTF-I from serotype c S. mutans PS14. The immunoreactivities of these MAbs were tested by enzyme-linked immunosorbent assay and Western blotting (immunoblotting) with various GTF preparations. GTF-I and GTF-SI were expressed from two Streptococcus milleri or Escherichia coli transformants harboring gtfB or gtfC, respectively. All of the five MAbs raised against the GTF-S from PS14 reacted only with the homologous enzymes. Of these, 8 MAbs reacted only with the gtfB gene product (GTF-I), 4 MAbs reacted only with the gtfC gene product (GTF-SI), and the remaining 16 MAbs reacted with both gene products. The existence of GTF-SI in the purified GTF-I from PS14 was demonstrated by Western blot analysis using the representative monospecific MAbs. Further, the relative levels of the three GTFs in the extracellular and cellular fractions of S. mutans clinical isolates were examined by immunoblot analysis. The findings indicated that the relative level of GTF-SI, unlike that of GTF-I or GTF-S, differed markedly among isolates although the three GTFs were synthesized extracellularly by all the strains.

Animals↗

Molecular cloning of a human cDNA encoding a novel protein, DAD1, whose defect causes apoptotic cell death in hamster BHK21 cells.

The tsBN7 cell line, one of the mutant lines temperature sensitive for growth which have been isolated from the BHK21 cell line, was found to die by apoptosis following a shift to the nonpermissive temperature. The induced apoptosis was inhibited by a protein synthesis inhibitor, cycloheximide, but not by the bcl-2-encoded protein. By DNA-mediated gene transfer, we cloned a cDNA that complements the tsBN7 mutation. It encodes a novel hydrophobic protein, designated DAD1, which is well conserved (100% identical amino acids between humans and hamsters). By comparing the base sequences of the parental BHK21 and tsBN7 DAD1 cDNAs, we found that the DAD1-encoding gene is mutated in tsBN7 cells. The DAD1 protein disappeared in tsBN7 cells following a shift to the nonpermissive temperature, suggesting that loss of the DAD1 protein triggers apoptosis.

Amino Acid Sequence↗

A mechanism of erythromycin treatment in patients with diffuse panbronchiolitis.

Recently, "low-dose and long-term" erythromycin treatment has been reported as effective on diffuse panbronchiolitis (DPB), but its mechanism is still obscure. Patients with DPB were found to have significantly higher percentages of neutrophils in the pre-erythromycin treatment bronchoalveolar lavage fluid (BALF) than healthy nonsmoking volunteers (p < 0.001). They showed a significant reduction in BALF neutrophil percentages after erythromycin treatment (p < 0.01). The neutrophil chemotactic activity (NCA) was significantly elevated in BALF obtained from 19 patients with DPB compared with that from healthy volunteers (p < 0.001). A significant reduction in the NCA was observed in post-erythromycin treatment BALF of 11 patients with DPB (p < 0.001). Additionally, there was a significant correlation between the reduction of NCA and neutrophil percentage in pre- and post-erythromycin treatment BALF (r = 0.726, p < 0.05). Finally, we investigated the effect of erythromycin on the intrapulmonary influx of neutrophils by intratracheal injection of lipopolysaccharide (LPS) and interleukin-8 (IL-8) in mice. The intrapulmonary influx of neutrophils was significantly suppressed (p < 0.001) in mice intraperitoneally injected with erythromycin at 5 mg per animal 2 h before intratracheal injection of LPS (control group: 6.5 +/- 1.6 x 10(5) versus erythromycin-treated group: 1.7 +/- 0.5 x 10(5)), but not 10 h before lung challenge. This inhibition was observed at 6 h after lung challenge and became maximal with 84% suppression at 24 h. Week-long administration of erythromycin did not alter the intrapulmonary influx of neutrophils. The number of neutrophils in the peripheral blood was not affected by erythromycin, indicating that the drug was not toxic.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

Elevation of tumor-associated carbohydrate antigens in patients with diffuse panbronchiolitis.

We investigated the serum levels of the tumor-associated carbohydrate antigens sialyl SSEA-1 (SLX) and sialyl Lewis(a) (CA19-9) in patients with diffuse panbronchiolitis (DPB) and other nonmalignant lung diseases. Both antigens were high in the serum and bronchoalveolar lavage fluid (BALF) of patients with DPB, bronchiectasis (BE), idiopathic pulmonary fibrosis (IPF), and interstitial pneumonia associated with collagen vascular disease (CVD). Markedly high levels of the antigens were demonstrated in the serum and BALF from patients with DPB. An immunohistochemical study of open-lung biopsy specimens from patients with DPB indicated that these antigens were selectively expressed on the bronchiolar epithelial cells and mucinous exudates in airspaces. Low-dose, long-term erythromycin (EM) treatment was recently reported to be effective for DPB, and we investigated its influence on serum and BALF antigen levels in DPB patients. Antigen levels in both serum and BALF decreased after EM treatment, with improvement of symptoms and laboratory data, and there was a significant correlation between the reduction in the SLX level in serum and neutrophil percentage in BALF pre- and post-EM treatment. Our result suggests that secreted carbohydrate antigens from the bronchiolar epithelium in DPB may appear in the serum as a result of airway damage in the lower respiratory tract, and serum levels of the antigens may be decreased by a reduction in neutrophils in BALF after EM treatment.

Adult↗

Metabolic fate of a new dihydropyridine calcium antagonist, CD-349, in rat and dog.

1. The metabolic fate of 14C-CD-349, a new calcium antagonist, was studied in rat and dog. 2. After oral administration of 14C-labelled drug in both species, the plasma levels of radioactivity reached maxima at 1-2 h and declined with elimination half-lives of 6-7 h. In both species, 71-85% of radioactivity was excreted in faeces and 17-27% in urine in 120 h. Biliary excretion in rat after oral doses amounted to 33%. 3. The low ratio of unchanged drug to total radioactivity in plasma suggested that CD-349 underwent rapid metabolism in both species. 4. Twenty-two metabolites were isolated and identified from dog urine and an incubation mixture with 9000 g rat liver supernatant. Principal routes of biotransformation of CD-349 were similar in both species, and involved: (1) oxidation of the dihydropyridine ring to the corresponding pyridine ring; (2) denitration of the nitrate ester; (3) hydrolysis of the carboxy ester to the carboxylic acid; and/or (4) oxidation of the side chain, although quantitative interspecies differences were observed.

Animals↗

[Meniscal transplantation with a synovial pedicle--an animal experiment].

The effect of a meniscal transplantation with a synovial pedicle in the avascular portion of the meniscus was investigated in an animal model. An inner (free edge side) half of the middle segment of the medial meniscus, about 6 mm in length, of an adult dog was resected, and a half thickness of the remaining outer (peripheral) meniscus was advanced with a synovial pedicle to fill in the resected portion and sutured with 6-0 interrupted Nylon sutures. As a control, the same procedure without the synovial pedicle was performed for comparison. Twenty-four dogs were treated with synovial pedicle and 13 without. The treated meniscus was excised every four weeks postoperatively up to 32 weeks for gross observation and histological examination. The histological findings at the junction between the advanced meniscus and the remaining meniscus in the group with the synovial pedicle were as follows: 1) At eight to 20 weeks, vascular proliferation and fibroblasts formation were present. 2) At 24 weeks, the vascularity decreased and the junction was filled with collagen fibers. 3) At 32 weeks, the junction was almost completely repaired with chondrocytes. In contrast, in the group without the synovial pedicle, the junction was connected with fibrous tissue, but with no chondrocytes even at 32 weeks. This enhancement of the meniscus repair with the synovial pedicle was considered to be due to reparative ability of the synovial cells, neovascularization through the synovium and viability of the advanced meniscus.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

In situ expression of the cell adhesion molecules in inflammatory bowel disease. Evidence of immunologic activation of vascular endothelial cells.

BACKGROUND: The cell adhesion between vascular endothelial cells and leukocytes is an important process for the immuno-inflammatory changes. To clarify the basic features of inflammatory bowel disease (IBD), studies of in situ localization of the cell adhesion molecules are required. EXPERIMENTAL DESIGN: We analyzed the immunohistochemical localization of the adhesion molecules (ICAM-1, LFA-1, Mac-1, VCAM-1, VLA-4, P- and E-selectins) in IBD, stressing phenotypical changes of endothelial cells. RESULTS: In the normal mucosa, ICAM-1 was expressed in capillaries and venules, LFA-1 in some lymphocytes and VLA-4 in most lymphocytes. VCAM-1 was expressed sporadically in venules and constantly in follicular dendritic cells (FDC) in lymphoid follicles. Both E- and P-selectins were sporadically expressed in venules. In actively inflamed mucosa in IBD, a marked increase of all these antigens was observed; ICAM-1+ inflammatory infiltrates (lymphocytes, plasma cells, and macrophages) and ICAM-1+ venules increased paralleled to the degree of inflammation. LFA-1+ and VLA-4+ mononuclear cells and Mac-1+ granulocytes increased in number. However, expression of VCAM-1 in venules or capillaries was not increased. FDC constantly expressed VCAM-1. E- and P-selectins+ venules increased in actively inflamed tissue particularly at the base of ulcers. Immunoelectron microscopy confirmed expression of these antigens along the plasma membranes (functional localization) and in rough endoplasmic reticulum or in perinuclear spaces (localization during the intracellular synthesis). CONCLUSIONS: Our study suggested that increased expression of the adhesion molecules in IBD promotes the recruitment of granulocytes and lymphocytes through blood vessels and the cell interaction between lymphocytes-antigen presenting cells or among lymphocytes, thereby sustaining the immuno-inflammatory process in IBD. The present study emphasizes the importance of microenvironmental changes including the endothelial activation in the immuno-inflammatory changes.

Adult↗

Cloning of a Streptococcus sobrinus oligo-isomaltosaccharide synthase gene and characterization of its product.

A Streptococcus sobrinus gene coding for a glucosyltransferase (GTF)-S was cloned into Escherichia coli, using the bacteriophage lambda L47.1 and the plasmid vector pACYC184. The MD124 clone obtained expressed a 155 kDa GTF-S which did not react with any antisera against GTF-S1, -S2 and -I enzymes. The recombinant enzyme (designated rGTF-S3) was homogeneously purified from the MD124 cell-extract and characterized. The purified rGTF-S3 synthesized primer-independently alpha-1,6-linked linear oligosaccharides from sucrose. The dependence upon the sucrose concentration was diphasic, and the respective Km values were 1.3 and 25 mM. The properties except the Km values were similar to those of oligo-isomaltosaccharide synthase from S. sobrinus AHT.

Chromatography, High Pressure Liquid↗