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Biomedical subjects

K Masuda

Publications and source records attributed to K Masuda.

At least 541 records · Page 30Linked to original sources
PubMed1989

Comparative characterization of spirosomes isolated from Lactobacillus brevis, Lactobacillus fermentum, and Lactobacillus buchneri.

Spirosomes, cytoplasmic fine spirals, were isolated and purified from Lactobacillus brevis ATCC 8287, L. fermentum F-1, and L. buchneri ATCC 4005, and their morphological, biochemical, and immunological properties were investigated. The spirosomes of these lactobacilli were morphologically indistinguishable from one another, and they had the same buoyant density of 1.320 g/cm3 in CsCl. All of the spirosomes were composed of a single protein, spirosin, with an apparent molecular weight of about 95,000 for L. brevis and L. fermentum and of about 96,000 for L. buchneri as estimated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). The spirosins from the three lactobacilli were compared by peptide mapping on SDS-PAGE after cleavage with N-chlorosuccinimide and limited proteolysis with Staphylococcus aureus V8 protease. The peptide map of the L. brevis spirosin was identical with that of the L. fermentum spirosin, whereas it was markedly different from the L. buchneri spirosin. The amino acid composition of the L. brevis spirosin was almost similar to that of the L. fermentum spirosin, while it differed appreciably from the L. buchneri spirosin. Using antiserum against the L. brevis spirosin, immunodiffusion test revealed that the antigenicity of the spirosomes from L. brevis was identical with that from L. fermentum, whereas it was partially different from that from L. buchneri.

Amino Acids↗
PubMed1989

Characterization and reassembly of a regular array in the cell wall of Clostridium difficile GAI 4131.

The cell wall of Clostridium difficile GAI 4131 was revealed by electron microscopy to have an outer layer composed of a nearly square array and contained the two major proteins with molecular weights of 38 kDa and 42 kDa. The properties and reassembly of the two major proteins into the regular array were investigated. When the isolated cell walls were treated with hydrophobic bond-disrupting agents or a chelating agent specific for Ca2+, the two major proteins were effectively removed and the regularly arranged outer layer disappeared. The amino acid composition of the two major proteins differed from each other. The two major proteins also gave different peptide maps from each other upon proteolysis with Staphylococcus aureus V8 protease. The major proteins solubilized from the isolated cell walls with 8 M urea or 4 M guanidine hydrochloride could be reassembled into open-ended cylinders possessing the native regular pattern by dialysis against neutral buffer containing 5 mM CaCl2. The reassembled cylinders purified by centrifugation on a Percoll density gradient were composed of almost equal amounts of the 38 kDa and 42 kDa proteins and freed from the other proteins. These results suggest that the regular array in the outer cell wall layer is constructed from the two major cell wall proteins and requires Ca2+ for its assembly.

Amino Acids↗
PubMed1989

Isolation and characterization of cytoplasmic fibrils from treponemes.

Electron microscopy of Triton X-100-treated whole cells of an oral treponeme, Treponema sp. strain E-21, revealed that six cytoplasmic fibrils (CFs) helically wound as a bundle in the cytoplasm. The CFs were isolated and purified by disruption and solubilization of the cells followed by CsCl density gradient centrifugation. The purified CF preparation contained mostly fibrils of about 9 nm in width and very small amounts of thinner strands of about 3 nm in diameter. The CFs were apparently seen to be a tubular structure, but the isolated CFs had narrowed sites of about 4-5 nm in width lacking lumen-like images, possibly representing twisted sites. Thus, the CF did not seem to be a tubular structure. The purified CFs were composed of one major 82 kDa protein and a few minor proteins. The CFs were destructed by treatment with proteases, 8 M urea or 4 M guanidine hydrochloride. Very low tyrosine content (0.76 mol %) and lack of methionine were characteristic features for the 82 kDa protein. The CF preparations from the other five treponemes including Treponema phagedenis and T. denticola also had 82 kDa proteins as a major component, and the 82 kDa proteins of all of the treponemes had a common antigen when examined by using antiserum against the 82 kDa protein from Treponema sp. strain E-21. Furthermore, the 82 kDa protein was demonstrated to be a principal component of the CFs of all the treponemes by immunoelectron microscopy.

Amino Acids↗
PubMed1989

Stimulation of interleukin 6-like B-cell differentiation factor production in human adherent synovial cells by recombinant interleukin 1.

Abnormal production of immunoglobulin in the joint space is frequently observed in patients with rheumatoid arthritis (RA). We have previously demonstrated that adherent synovial cells (ASC) from patients with RA are involved in B-cell differentiation by their spontaneous production of B-cell differentiation factor (BCDF). The regulation of the production of this factor, however, has not yet been described. We investigated the effects of recombinant interleukin 1 alpha and beta (rIL-1 alpha and rIL-1 beta) on the production of BCDF in ASC. Increased production of BCDF was observed with increased rIL-1 concentration. Production of BCDF was detected 3 h after exposure of ASC to rIL-1 and increased throughout a 48-h culture. This BCDF, assayed on SKW6-CL4 cells, was found to share a common active site with interleukin 6. The effect of rIL-1 was almost neutralized by anti-IL-1 antibody and the addition of polymyxin B did not diminish the effect of rIL-1, indicating that rIL-1 itself stimulates ASC in vitro. These results suggest that IL-1 may play a regulatory role in the production of BCDF in synovial tissue.

Cell Adhesion↗
PubMed1989

In vitro and in vivo activities of QA-241, a new tricyclic quinolone derivative.

The in vitro susceptibilities of 1,310 clinical isolates to QA-241, a novel tricyclic quinolone, were evaluated in comparison with susceptibilities to norfloxacin, ofloxacin, enoxacin, and ciprofloxacin. The MICs of QA-241 for 90% of staphylococci, Enterococcus faecalis isolates, and streptococcal species ranged from 1.56 to 6.25 micrograms/ml, and the activity of QA-241 was similar to those of norfloxacin and enoxacin but two to four times less potent than those of ofloxacin and ciprofloxacin. At the concentration of less than or equal to 1.56 micrograms/ml, QA-241 inhibited 90% of Haemophilus influenzae, Bordetella pertussis, Neisseria gonorrhoeae, and gram-negative enteric bacteria except for Serratia marcescens and Citrobacter freundii. QA-241 was moderately active (MIC for 90% of strains tested, 6.25 to 12.5 micrograms/ml) against S. marcescens, Pseudomonas aeruginosa, Xanthomonas maltophilia, and Bacteroides fragilis. The antibacterial activity of QA-241 was roughly comparable to that of enoxacin but two to four times less potent than that of ofloxacin. In systemic infections in mice with gram-positive cocci and gram-negative rods, the efficacy of QA-241 was generally greater than that of norfloxacin and similar to those of ofloxacin and ciprofloxacin. In urinary tract infections in mice with Escherichia coli or Pseudomonas aeruginosa, QA-241 was as active as ofloxacin and more active than norfloxacin but less active than ciprofloxacin. In pulmonary infections in mice with Klebsiella pneumoniae, the effectiveness of QA-241 was similar to that of ofloxacin.

4-Quinolones↗
PubMed1989

Spontaneous lymphoblastoid transformation of cells obtained from human tonsils.

Spontaneous lymphoblastoid transformation of cells obtained from 25 human tonsils were investigated. Three Epstein-Barr virus (EBV) genome-positive lymphoblastoid cell lines were spontaneously established in tissue cultures in vitro from human tonsils. In addition, the frequency of spontaneous lymphoblastoid transformation was increased by the treatment of tumor promoter, 12-0-tetradecanoylphorbol-13-acetate and 18 lymphoblastoid cell lines were established. The data suggest that the human tonsil is a reservoir for EBV.

Adolescent↗
PubMed1989

Characteristics of Epstein-Barr virus-carrying lymphoblastoid cells derived from human tonsil: EBV production and autoantibody response.

Tonsillar and peripheral blood lymphocytes from 20 patients with tonsillitis were examined for production of Epstein-Barr virus (EBV) and antinuclear antibodies within 2 weeks after EBV transformation. All established lymphoblastoid cell lines (LCLs) contained more than 90% EBV nuclear antigen-positive cells. However, no LCLs produced biologically active virus. On the other hand, 10 (50%) out of 20 tonsillar LCLs and 4 (20%) out of 20 peripheral blood LCLs produced autoantibodies. These results showed that there are differences in an EBV-induced lymphocyte autoantibody response between tonsillar lymphocytes and peripheral blood lymphocytes.

Antibodies, Antinuclear↗
PubMed1989

Development of significant sternoclavicular joint hypertrophy following radical neck dissection.

Radical neck dissection (RND) has proved to be effective in the en bloc removal of metastatic lymph nodes in the neck. This paper describes a case with severe sternoclavicular joint hypertrophy following RND. This condition should be differentiated both clinically and radiologically from metastases of the head of the clavicle. Computed tomography was found to be of value in the diagnosis of the condition.

Aged↗
PubMed1989

Malignant fibrous histiocytoma arising from the vocal cord.

A rare case of malignant fibrous histiocytoma of the left vocal cord occurring in an 80-year-old man is described, with a review of the literature. There has been no recurrence for 24 months since the initial endolaryngeal microsurgery.

Aged↗
PubMed1989

Heterogeneity of Fc receptor expression in chemotaxis and adherence of neonatal neutrophils.

Chemotaxis and adherence to polymorphonuclear neutrophils (PMN) subpopulations from cord blood of 13 healthy neonates and blood of 16 healthy adults as control subjects were determined using the rosette-forming procedure, the modified Boyden method, and 51Cr adherence assay. The percentage of rosette-forming neutrophils (RFN) (Fc receptor expression) of cord PMN (35 +/- 8%) was significantly lower than that of adult PMN (60 +/- 4%, p less than 0.01). Differences in chemotaxis of PMN subpopulations between cord and adult PMN after stimulation by their own endotoxin-activated plasma were as follows: (i) unfractionated adult PMN (A) (n = 10) versus adult RFN (B) (n = 5) versus adult nonRFN (C) (n = 5); (A) less than (B), p less than 0.01 and (A) greater than (C), p less than 0.01; (ii) unfractionated cord PMN (a) (n = 5) versus cord RFN (b) (n = 5) versus cord non-RFN (c) (n = 5); (a) less than (b), p less than 0.01 and (a) versus (c), NS; (iii) (A) greater than (a), p less than 0.01; (iv) (B) greater than (b), p less than 0.05 and (C) versus (c), NS. Similarly, differences in adherence were as follows: (i) (A) (n = 13) versus (B) (n = 4), NS and (A) greater than (C) (n = 4), p less than 0.01; (ii) (a) (n = 4) versus (b) (n = 4), NS and (a) greater than (c) (n = 4), p less than 0.01; (iii) (A) greater than (a), p less than 0.05; (iv) (B) versus (b), NS and (C) versus (c), NS. These results suggest that differences in chemotaxis and adherence between cord and adult PMN may relate in part to differences of PMN subpopulations.

Cell Adhesion↗
PubMed1989

HTLV-I-associated myelopathy with adult T-cell leukemia.

We report a 42-year-old Japanese woman with HTLV-I-associated myelopathy (HAM) combined with adult T-cell leukemia (ATL). Combination of the 2 diseases has been extremely rare. The infrequency is explained by HLA types unique to each disease. Our patient suggests that the HAM-associated HLA haplotype does not prevent the development of ATL.

Adult↗
PubMed1989

Effect of FK973, a new antitumor antibiotic, on the cell cycle of L1210 cells in vitro.

Our previous study showed that FK973 (11-acetyl-8-carbamoyloxymethyl-4-formyl-14-oxa-1,11- diazatetracyclo[7.4.1.0(2,7)0(10,12)]tetradeca-2,4,6-trien-6 ,9-diyl diacetate), a novel substituted dihydrobenzoxazine, which is a derivative of the fermentation product of Streptomyces sandaensis No. 6897, had strong antitumor effects on experimental tumors in vitro and in vivo. In this report, we investigated its effect on the cell cycle of murine leukemia L1210 cells in vitro by means of DNA/5-bromo-2'-deoxyuridine double staining and compared these effects with those of other antitumor drugs. Both FK973 and mitomycin C arrested the cells in the G2 phase. Vinblastine arrested the cells in the M phase and cytosine arabinoside, in the G1 phase. Although FK973 and mitomycin C were shown to act on the cell cycle in a similar way, FK973 was slower in producing its effect. From the results, FK973 arrests the cells in the G2 phase, and it appears that FK973 must be converted into the activated form in the cells for the development of its antitumor effects.

Animals↗
PubMed1989

A new antitumor antibiotic, FK973: its metabolism in the blood and the antitumor effects of its metabolites on experimental models.

Our previous studies showed that a new, substituted dihydrobenzoxazine, FK973 (11-acetyl-8-carbamoyloxymethyl-4-formyl-14-oxa-1,11-diazatetracyclo+ ++- [7.4.1.0(2,7).0(10,12)tetradeca-2,4,6-trien-6,9-diyl diacetate), which is a triacetylated derivative of the fermentation product FR900482 of Streptomyces sandaensis No. 6897, had potent antitumor effects on experimental tumors in vivo and in vitro. In the present study, we investigated the metabolism of FK973 in the blood of human and animals and the antitumor effects of its metabolites. After the incubation of FK973 in the blood (hemolysate) or serum of humans, dogs, rats and mice, it was rapidly metabolized to two diacetates and a monoacetate, and slowly to FR900482. FK973 and all its deacetylated metabolites showed strong cytotoxicity on in vitro cultured murine L1210 leukemia cells, and the cytotoxicity of FK973 was the most potent. In the vivo experiments, FK973 and its metabolites prolonged the life of mice bearing ascitic P388 leukemia, and it potently inhibited the growth of murine B16 melanoma and Colon 38 adenocarcinoma implanted subcutaneously in mice. FK973 was the most effective compound. Thus, these results suggest that the antitumor effects of FK973 are stronger than those of its deacetylated metabolites produced in the blood of humans and animals.

Animals↗
PubMed1989

Differences in the ability of cells to fuse are mediated by strains of Epstein-Barr virus.

Epstein-Barr virus (EBV) preparations from both NPC-KT cells (NPC-EBV) and P3HR-1 cells (HR-1-EBV) can induce cell fusion between EBV receptor (EBVR)-positive Raji cells and EBVR-negative cells, but other strains of EBV cannot induce cell fusion. The effect of these two EBV isolates on ability of cells to fuse has been studied to determine if there are differences in the biological properties of the different EBV isolates, particularly the isolates obtained from nasopharyngeal carcinoma such as NPC-EBV. The frequency of cell fusion between NPC-EBV-superinfected Raji cells and EBVR-negative epithelial cells (Ad-AH) was increased more than 30-fold in the presence of medium containing 1% dimethylsulfoxide (DMSO). However, the frequency of cell fusion between HR-1-EBV-superinfected Raji cells and Ad-AH cells was unaffected under the same conditions. The data show that differences in the ability of cells to fuse are induced by variants of EBV in response to DMSO. These differences may be important in elucidating the different biological properties of EBV isolates and might have implications for the pathophysiology of EBV-associated illness.

Cell Fusion↗
PubMed1989

Further studies on growth characteristics of Epstein-Barr virus (EBV) genome-positive and -negative epithelial hybrid cell lines.

Differences in tumorigenicity between the Epstein-Barr virus (EBV) genome-negative and -positive epithelial A2L/AH hybrid cell lines have been described recently. Further differences in growth characteristics of the two epithelial hybrid cells have since been examined. Differences were found in doubling time and cloning efficiency in agarose of the two cell lines. In addition, the EBV genome-negative epithelial hybrid cell line (cl-654), unlike the EBV genome-positive epithelial hybrid cell line (cl-1), failed to grow in the unmanipulated nude mice, but was successfully transplanted in 60Co-irradiated nude mice. The histopathologic findings of tumors induced by the inoculation of cl-654 cells in nude mice showed more differentiated carcinoma than the findings of tumors induced by cl-1 cells. The data suggest that EBV is associated with an alteration of cell differentiation in epithelial cells as well as tumorigenicity in nude mice.

Animals↗
PubMed1989

[Eight cases of non-resectable hepatocellular carcinoma surviving for more than 3 years after Lipiodol administration].

From December 1982 to February 1986, selective regional cancer chemotherapy using Lipiodol plus anticancer drug (Lipiodolization) was prescribed for 87 patients with non-resectable hepatocellular carcinoma (HCC). Eight out of 87 cases survived for more than 3 years. The mean age of the 8 long survivors was 52.6. In the liver function, 2 cases were in Child A, 5 cases in Child B, and 1 case in Child C. The largest diameter of HCCs was 5.3 cm, and the number of the tumors was one in 6 cases, two in one case, and three in one case. No vascular invasion was detected on hepatic angiography. These findings suggested that long survivors in lipiodolization are not in far advanced HCCs. For these 8 cases, lipiodolization was repeatedly prescribed from two to 6 times. The largest amount of adriamycin was 192 mg/case. The longest survivor has lived for 5 years and 6 months after first lipiodolization. After lipiodolization, one tumor vanished, and three tumors decreased in size. Although seven tumors increased in size after lipiodolization, the tumor doubling time of seven tumors were 64, 265, 313, 317, 350, and 1943 days (average 539 +/- 639 days). It is possible that lipiodolization remarkably inhibited tumor growth. Nevertheless, in 5 out of 7 cases, the daughter lesions increased in size and number, although the main tumors grew slowly. Lipiodolization was less effective for newly arising daughter lesions than main lesions.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1989

[The effect of acetate Ringer dextrose (5%) and lactate Ringer dextrose (5%) in surgical patients].

The clinical evaluation of acetate ringer dextrose (AR-D) for hemodynamic status, metabolism of glucose, electrolytes in serum and urine, liver and renal function and acid-base balance were performed in surgical patients compared with lactate ringer solution (LR-D). The 20 patients scheduled for gynecological operations were randomized into 2 groups. After the administration of AR-D or LR-D, we examined their clinical effects. The results suggest that there were no significant differences between AR-D group and LR-D group. We cannot confirm that AR-D is a better solution for surgical patients than LR-D regarding metabolism of lactate, pyruvate and glucose during operations.

Adult↗