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S Harada

Publications and source records attributed to S Harada.

At least 505 records · Page 28Linked to original sources
PubMed1987

Quantitative analysis of cytotoxicity induced by HTLV-I carrying cells against a human lymphoblastoid cell line, Molt-4.

Co-cultivation of HTLV-I carrying cells and virus-free lymphoid cells resulted in the cytopathic effect and cytotoxicity of the latter cells. Microscopically, these phenomena were observed as early as 2 h as the appearance of multinuclear giant cells and ballooning cells with striking resemblance with cytopathic changes induced by HTLV-III. When the cytopathic effect and cytotoxicity of the target cells by HTLV-I carrying cells were assayed by 51Cr-release assay system, these phenomena were quantitatively analysed and the cytotoxic activity was observed generally in HTLV-I positive cells. Virally induced cytotoxicity was inhibited by plasma of adult T-cell leukemia (ATL) patients specifically. Cytotoxic activity of HTLV-I positive cell lines was correlated with HTLV-I antigen expression of them. HTLV-I negative cell lines did not express cytotoxicity significantly.

Cell Line↗
PubMed1987

Clonal analysis of functional differences among strains of human immunodeficiency virus (HIV).

Different isolates (HTLV-IIIB, LAV1 and ARV2) of human immunodeficiency virus (HIV) were cloned by a plaque-forming assay using MT-4 cells. The reverse transcriptase (RT) activity and plaque-forming unit (PFU) titers of all viral preparations were assayed. PFU/RT values, which indicate the relative proportions of incomplete and infectious viruses, were used for determination of viral infectivity. High values were obtained mainly for clones of HTLV-IIIB and LAV1, and low values for ARV2-derived clones, suggesting that ARV2 and its clones were genetically less infectious. For studies on cytocidal effects of the viruses, four clones of HTLV-IIIB, LAV1 and ARV2 were selected that had similar PFU/RT (infectivity) values for proliferation in infected MT-4 cells. When compared at the same dose (MOI), one clone (HTLV-IIIB-C-2) was found to be more cytocidal than the others. Furthermore, plaques induced by HTLV-IIIB-C-2 were larger than those induced by other clones, suggesting that the release of progeny from HTLV-IIIB-C-2-infected cell and their proliferation were the most efficient. Among the cloned viruses tested, three were found to induce strong cytopathic changes (fusion and ballooning) selectively in MT-4 cells. Thus, the infectivity, proliferation and cytopathic fusion-effects were proposed to be encoded by the viral genome and be separable by the plaque-cloning method.

Cell Fusion↗
PubMed1987

Relative deficiency of serine proteinase activities in spleens of aged mice.

We examined the relation of hydrolytic enzymes in spleen to the aging process in mice over a period of 30 months. When the enzymatic activities were expressed as activities per milligrams protein, those of serine proteinases and dipeptidyl peptidase IV (Gly-Pro-AP) significantly decreased with age, whereas that of L-leucine aminopeptidase (Leu-AP) increased significantly. However, when expressed as total activities, the enzymatic activities in spleen generally tended to increase with age, except in the case of serine proteinases, because of the age-related increase in spleen weight. The results were taken to indicate that the activities of serine proteinases become relatively more deficient in the spleen as age increases. The results of a multivariate study maintained this peculiarity of serine proteinases in comparison with other enzymes. The relative deficiency of serine proteinases in spleen may be somehow related to immunodeficiency in aged animals, as judged from similar findings in animal models of systemic erythematodes.

Aging↗
PubMed1987

Chemistry and inhibitory activity of long chain fatty acid oxidation of emeriamine and its analogues.

Emericedins A, B, and C, new betaines having inhibitory activity of long chain fatty acid oxidation, were isolated from the culture broth of Emericella quadrilineata IFO 5859. Their structures were determined by spectroscopic analyses as (R)-3-(acylamino)-4-(trimethylammonio)butyrate (acyl: A, acetyl; B, propionyl; C, n-butyryl). Structural confirmation and assignment of absolute configuration were made by chemical synthesis from L-asparagine. Deacylation of emericedin gave a potent derivative, (R)-3-amino-4-(trimethylammonio)butyrate, designated as emeriamine. In order to study the structure-activity relations, various analogues of emeriamine, including a stereoisomer, were prepared. Among them, N-palmitoyl and N-myristoyl derivatives showed much stronger inhibition of fatty acid oxidation than emeriamine.

Animals↗
PubMed1987

A quantitative enzyme-linked immunosorbent assay for Dermatophagoides pteronyssinus-specific immunoglobulin G.

A monoclonal mouse anti-human IgG was used to develop an enzyme-linked immunosorbent assay (ELISA) for the measurement of Dermatophagoides pteronyssinus (DP)-specific IgG in human sera. This monoclonal antibody (HG2-25) binds to all subclasses of IgG but not to IgA, IgM, or IgE. For the assay, the DP antigen is coated firmly on polystyrene beads through physical adsorption and any leakable antigen is washed off. The assay gives satisfactory reproducibility and parallelism of the dilution curves. Using 0.1% human serum albumin as a substitute for the DP-specific IgG preabsorbed diluent gave extremely low backgrounds and high sensitivity. Horseradish peroxidase-labeled HG2-25 prepared with the optimum degree of conjugation and free of polymerized conjugates gave responses fairly proportional to the doses. This ELISA gives a satisfactory recovery and is not affected by nonspecific IgG levels in human sera.

Animals↗
PubMed1987

Molecular cloning and nucleotide sequence of the 3-isopropylmalate dehydrogenase gene of Candida utilis.

A 3-isopropylmalate dehydrogenase (3-IMDH, EC 1.1.1.85) gene was cloned from a gene library of Candida utilis. One of the plasmids, pYKL30, could complement Escherichia coli leuB and Saccharomyces cerevisiae leu2 auxotrophs; a 2.2 kb HindIII fragment subcloned in pBR322 could still complement the leuB mutation. Southern hybridization confirmed that this fragment was derived from C. utilis. An open reading frame of 1089 bp that corresponded to a polypeptide of 363 amino acids, one residue shorter than the 3-IMDH of S. cerevisiae, was found in the cloned fragment. The homology between the 3-IMDHs of C. utilis and S. cerevisiae was 76.2% in nucleotides and 85.4% in amino acids. In contrast, the homology between the 3-IMDHs of C. utilis and Thermus thermophilus was much smaller and was restricted to some regions of the gene.

3-Isopropylmalate Dehydrogenase↗
PubMed1987

Elimination of viruses (human immunodeficiency, hepatitis B, vesicular stomatitis and Sindbis viruses) from an intravenous immunoglobulin preparation.

More than 10(4) plaque-forming units (pfu)/ml of HIV are inactivated during the alcohol fractionation step from plasma to fraction (Fr)-II+III, greater than 10(4) pfu/ml is inactivated from Fr-II+III to Fr-II and greater than 10(4) pfu/ml is inactivated during the polyethylene glycol (PEG) fractionation process from Fr-II+III to intravenous IgG (IVIG). The total inactivation rate from plasma to IVIG via Fr-II+III or Fr-II was calculated to be greater than 10(8) or 10(12), respectively. The PEG fractionation method produces an intact and unmodified IVIG. In addition, the PEG fractionation method at a low ionic strength was found to be effective for the elimination of greater than 10(5) units of other viruses, including hepatitis B, vesicular stomatitis and Sindbis viruses.

Chemical Fractionation↗
PubMed1987

Renal magnesium wasting in a patient with short bowel syndrome with magnesium deficiency: effect of 1 alpha-hydroxyvitamin D3 treatment.

We studied a patient with severe hypomagnesemia due to small bowel resection who had marked renal magnesium (Mg) loss in response to iv Mg infusion. She had an undetectable serum 1,25-dihydroxyvitamin D [1,25-(OH)2D] level before treatment. Although Mg infusion increased her serum Mg levels and enhanced renal PTH action, as evidenced by an elevation in nephrogenous cAMP, the serum 1,25-(OH)2D level remained low. After the administration of 1 alpha-hydroxyvitamin D3, her serum 1,25-(OH)2D level increased, and fractional excretion of Mg decreased. With the elevation in serum 1,25-(OH)2D, serum Mg levels could be maintained without Mg infusion, although they were still subnormal. These results are consistent with the assumption that patients with the short bowel syndrome and Mg deficiency have reduced renal tubular Mg reabsorption which causes renal Mg loss, and that impaired tubular Mg reabsorption is due at least in part to deficient renal action of 1,25-(OH)2D. Because depressed serum 1,25-(OH)2D levels cannot be corrected rapidly by Mg infusion, administration of 1 alpha-hydroxyvitamin D3 or 1,25-(OH)2D3 appears to be the treatment of choice for Mg deficiency in patients with short bowel syndrome.

Adult↗
PubMed1987

An unsuccessful attempt to isolate human immunodeficiency virus (HIV) from patients with primary immunodeficiency diseases.

Isolation of the human immunodeficiency virus (HIV) was performed in 5 seronegative patients with primary immunodeficiency diseases (IDDs) who had no or little ability to produce antibodies and received a large amount of intravenous gammaglobulin (IVG) for a long period. In this study cultured cells were considered to be infected if the following 2 criteria were met: (1) They produced reverse transcriptase (RT) activity in the supernatant fluid and (2) expressed viral antigens. Under experimental conditions, virus was demonstrated by both RT activity and viral antigen expression detectable by immunofluorescence technique in lymphocyte cultures from 2 seropositive patients with acquired immunodeficiency syndrome-related complex who were examined as controls. There was no evidence of HIV infection in cultures of lymphocytes from all of the 5 patients with primary IDDs and from 2 healthy subjects. The above patients did not show the extremely low numbers of target T4+ cells, which make isolation of the virus in lymphocytes difficult. The present results suggest that current methods of IVG preparation either remove or inactivate HIV.

Adult↗
PubMed1987

A new pyrrole-amidine antibiotic TAN-868 A.

A new pyrrole-amidine antibiotic TAN-868 A was isolated from the culture broth of Streptomyces idiomorphus sp. nov. Its chemical structure was determined by spectroscopic analyses and degradation studies to be 4-[(2S,4R)-4-hydroxy-5-iminoprolyl]amino- N-(2-amidinoethenyl)-2-pyrrolecarboxamide. The antibiotic is active against bacteria, fungi and a protozoan, and has cytotoxic activity against murine tumor cells. DNA thermal denaturation studies suggest that TAN-868 A preferentially interacts with AT rich regions of double-stranded DNA.

Anti-Bacterial Agents↗
PubMed1987

Inflammatory mediators and modulators released in organ culture from rabbit skin lesions produced in vivo by sulfur mustard. III. Electrophoretic protein fractions, trypsin-inhibitory capacity, alpha 1-proteinase inhibitor, and alpha 1- and alpha 2-macroglobulin proteinase inhibitors of culture fluids and serum.

This is the third report in a series on the inflammatory mediators and modulators released in organ culture from skin lesions of various ages, which were produced in vivo in rabbits by the military vesicant, sulfur mustard (SM). It describes the electrophoretic protein fractions and trypsin-inhibitory capacities of the various culture fluids and the amounts of alpha 1-proteinase inhibitor and alpha-macroglobulin proteinase inhibitors in these fluids. With one-dimensional electrophoresis, the albumin and beta-globulin fractions of protein in culture fluids varied little with the development and healing of the SM lesions. These fractions proportionally resembled the corresponding fractions found in serum. The alpha 1-globulin fraction was proportionally smaller than the corresponding fractions of serum as the lesions healed. The alpha 2-globulin fraction was proportionally smaller than the corresponding fractions of serum at all stages of lesion development and healing. The gamma-globulin fraction was proportionally larger as the lesions healed. With two-dimensional electrophoresis, about 68%, 46%, and 35% of the protein spots in culture fluids from representative 1-day and 6-day SM lesions and normal skin, respectively, matched those from serum. In each case, the large, diffuse, serum albumin spot represented about two-thirds of the protein present. Thus, gravimetrically, in normal skin and in both developing and healing lesions, the extracellular proteins were 80-90% of serum origin. The trypsin-inhibitory capacity (TIC) per milligram protein in the culture fluids of healing lesions was markedly less than the TIC per milligram protein in the fluids of peak lesions. This decrease correlates well with the decrease found in the alpha 1-globulin fraction, which contains alpha 1-antiproteinase (alpha 1-PI) (and alpha 1-macroglobulin [alpha 1M] in rabbits). The alpha 1PI and the alpha 1M-alpha 2M proteinase inhibitors were identified in the culture fluids by means of sodium dodecyl sulfate-polyacrylamide gel electrophoresis, Western blots, specific antibodies, and the immuno-peroxidase technique. The levels of both free and proteinase-complexed alpha 1PI and alpha M inhibitors in the culture fluids decreased as the lesions healed. In both developing and healing lesions, at least half of the alpha 1PI and alpha M inhibitors seemed to be complexed with proteinases. Thus, serum seems to be a major source of unbounded extracellular protein within acute inflammatory lesions, and serum proteinase inhibitors seem to be the host's major defense against local damage by proteinases from serum, infiltrating leukocytes, and activated fibroblasts.

Aging↗
PubMed1987

AIDS studies in Japan.

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Acquired Immunodeficiency Syndrome↗
PubMed1987

Dissociation between serine proteinases and proline related enzymes in spleen of MRL mouse as a model of systemic lupus erythematodes.

We investigated the changes in the activities of proteases and other hydrolytic enzymes in spleens of MRL mice as a model of systemic lupus erythematodes (SLE). Although there are various abnormalities in the activities of proteases in the spleens of such animals, a multivariate study helped to extract two important components. The first component, representing the activities of serine proteinases, tended to decrease with advancing age in MRL mice but not in control animals. The second component, representing Pro-IP and prolyl endopeptidase, tended to decrease with advancing age in control animals, but not in the MRL mice. The discrepancy between these two components may be related to the immunopathologic disturbances in this model.

Animals↗
PubMed1987

Decreased activities of serine proteinases in spleen of various murine models of systemic lupus erythematodes.

Previous studies indicated a relationship between immune deficiencies and abnormalities in the activities of various hydrolytic enzymes, including proteinases, in tissues. In the present study, we compared such activities in spleen among the three types of murine models of systemic lupus erythematodes (SLE) (i.e., New Zealand black/white mouse, MRL mouse, and BXSB mouse) and their controls. According to the results of multivariate analysis, it was shown that the most important enzymatic changes differentiating the pathologic animals from their controls were decreases in the activities of serine proteinases. Judging from the behavior of these enzymes in various immunological disturbances, it is likely that they play some important roles in pathophysiology of SLE.

Animals↗