Biomedical subjects
Publications and source records attributed to A Okano.
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We examined the effect of human recombinant (r) interleukin 6 (IL-6) on the differentiation of murine and human hemopoietic progenitors. Human IL-6 supported colony formation by murine bone marrow cells. These colonies consisted of neutrophils and macrophages. Recombinant IL-6 was able to support multilineage colony formation by spleen cells from 5-fluorouracil (5-FU)-treated mice. These colonies consisted of greater than 1 x 10(4) cells. Differential counts revealed large colonies exhibiting different combinations of cell lineages: neutrophils, macrophages, eosinophils, mast cells, and megakaryocytes. However, when blast cell colonies supported by interleukin 3 were replated into secondary dishes containing IL-6, they could differentiate into only neutrophils and macrophages. Single cells transferred from blast cell colonies formed only neutrophil/macrophage colonies. These results indicate that IL-6 had a direct effect on the growth and development of murine granulocyte-macrophage progenitors at a late stage and a significant effect on multipotential hemopoietic precursors that might be indirect through other cells. By contrast, human rIL-6 did not support colony formation by human bone marrow mononuclear cells. IL-6 may not show an independent activity for human hemopoiesis of myeloid lineage. However, the synergistic activity of IL-6 remains to be clarified.
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Multiple sclerosis is considered to be an autoimmune demyelinating disease of the central nervous system. Damage to the blood-brain barrier, of which endothelial cells are the main constituent, occurs in multiple sclerosis, probably due to immunological mechanisms. We report here the results of immune-mediated damage to these cells, produced by immunizing guinea pigs with an endothelial cell membrane fraction. The fraction was obtained from cerebral endothelial cells grown in vitro and was free from myelin basic protein. The immunized animals developed a chronic neurological illness with evidence of delayed hypersensitivity to the cell membrane fraction but not to myelin antigens. Histological examination of the brain in the acute stage showed mononuclear cell infiltrates around blood vessels, while in the chronic phase large areas of demyelination, especially in the periventricular region, were present. This bore a striking similarity to the brain in multiple sclerosis. This may prove to be a useful new animal model for the investigation of the human demyelinating disease.
To learn about the progress of postpartum uterine involution in the dairy cow, the authors wanted to know whether the ultrasonic linear scanner is applicable for this purpose. The uterus was observed by the transducer, which was inserted into the rectum. Clear cross-sectional images of the endometrium were obtained in this way; however, those of the myometrium and the perimetrium were not very clear. Observation on the progress of uterine involution was started on Day 8 postpartum and continued to Day 43 postpartum. The diameter and area of the uterine horn and the endometrium in cross-sectional ultrasonograph images of the endometrium were estimated using a Magiscan 2 image analyzer. The relationship between the estimated dimensions of the uterine horn and postpartum days were satisfactorily fitted into polynomial regressions. Using the ultrasonic linear scanner, it was confirmed that uterine involution was completed at approximately 40 d postpartum. The applicability of the ultrasonic linear scanner for diagnosis of uterine involution in the postpartum cow is demonstrated by the results of the present study.
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Proteose-peptone-induced intraperitoneal neutrophils from rats were activated in terms of tumor cytotoxicity by pretreatment with culture supernatants from a human T cell leukemia line, Jurkat (culture sup). Culture sup-treated neutrophils showed cytotoxicity against various tumor cell lines. The cytotoxicity of culture sup-treated neutrophils was dependent on the number of neutrophils and the concentration of culture sup. Cytostasis by activated neutrophils was observed very early in the assay incubation period (within 6 hr), but cytolysis first occurred at 24 hr after the start of incubation. Factor(s) in culture sup responsible for the activation of cytotoxic neutrophils were stable to temperature and pH treatments, and their molecular weight was higher than 10,000. The responsible factor(s) for activation of cytotoxic neutrophils were different from interleukin-2, serum-derived factor, and bacterial lipopolysaccharide.
Cefotiam (CTM) and cefmenoxime (CMX) were studied for their serum concentrations and transference into bile in patients with PTCD or T-tube. One gram of CTM or either 1 g or 2 g of CMX was administered by an intravenous drip infusion for over 30 minutes. These drugs were also studied for their serum concentrations, bile concentrations, and tissue concentrations in the walls of the gallbladder of patients operated on for cholelithiasis. Intravenous drip infusion (over 30 minutes) was used to administer 1 g of CTM or 1 g or 2 g CMX immediately before surgery. Both CTM and CMX were readily transferred into bile. Their bile concentrations, however, varied greatly among patients, and extremely low levels were detected in some patients. A crossover analysis of concentrations of CMX in bile of patients given doses of 1 g and 2 g revealed a dose-response relationship. The crossover analysis of drug concentrations in bile of patients given CTM and CMX showed that CMX is transferred more readily to bile. The relationship between liver functions and drug transfer to bile was examined by plotting the total bilirubin level against drug concentrations in bile. The plots formed an exponential curve with a correlation coefficient (r) being -0.52 in cases when each subjects received 1 g of CTM and -0.72 in cases when each subjects received 1 g of CMX. A study of 3 patients given CMX at a dose of 1 g suggested that bile levels of CMX may be correlated to ICG. Concentrations of CTM and CMX in tissues of the gallbladder wall were fairly high, with unexpectedly small variance among patients. Even in patients with low bile concentrations of these drugs, drug levels in the tissues of the gallbladder wall were high. Drug levels in the noninflammatory tissues were higher than those in inflammatory lesions. The above findings suggest that CTM should be the antibiotic of choice for patients with ordinary biliary tract infections and after the surgery of the liver and biliary tract system, while CMX should be the antibiotic of choice for patients with severe biliary tract infections, and for compromised hosts after the surgery of the liver and biliary tract system.
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Circulating immune complexes were assayed in the sera of animals with experimental allergic neuritis (EAN), and immunofluorescent staining and immunohistological examination were performed to clarify the role of immune complexes in the pathogenesis of EAN. The level of immune complexes in the sera of animals with clinical signs of EAN was from 1:32 to 1:64. Control animals showed a titer of immune complexes from 1:2 to 1:4. Animals with EAN showed deposition of immune complexes, which were detected by FITC-conjugated anti-rat IgG or C3-complement, in the vessels of the peripheral nerve. These findings suggest that immune complexes may contribute to the immunopathogenesis of EAN.
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A tropomyosin has been purified from porcine kidney and its properties compared with those of rabbit skeletal muscle tropomyosin. Kidney tropomyosin was separated from contaminating vascular smooth muscle tropomyosin by hydroxylapatite chromatography. Kidney tropomyosin resembles tropomyosin from other non-muscle cells in regard to subunit size, mobility on SDS-polyacrylamide gels in the presence and absence of 6 M urea, amino acid composition and morphology. The binding of tropomyosin to F-actin is strongly dependent on the Mg2+ concentration. With kidney tropomyosin, binding begins at 1 mM Mg2+ and is complete at about 4-5 mM, while with muscle tropomyosin, binding is initiated at 1 mM Mg2+ and reaches saturation at 2-3 mM Mg2+. Both kidney and muscle tropomyosins bind to actin in a similar ratio of 1 tropomyosin/6-7 actin monomers at saturation. Both kidney and skeletal muscle tropomyosins prevent "severing" of F-actin filaments induced by gelsolin/villin-like protein purified from kidney. These results suggest that, in non-muscle cells, tropomyosin may protect microfilaments from Ca2+-dependent solation at the site where they may interact with myosin.
Amyloid fibril protein was purified from organs of patients with familial amyloid polyneuropathy (Nagano prefecture, Japan). When compared with amyloid fibril protein from primary amyloidosis and secondary amyloidosis, the protein from familial amyloid polyneuropathy was shown to differ in the molecular weight of the subunit. This protein subunit had the same molecular weight as the prealbumin subunit, but had a different amino acid composition: It did not contain tryptophan and cysteine. Amyloid fibril protein from familial amyloid polyneuropathy therefore differed from IgG, AA protein, and prealbumin.
When lyophilized myelin prepared from canine brain white matter was extracted with a solvent mixture of n-propanol-n-hexane (2:3, v/v), it was found that the extract contained less amounts of sulfatide and phosphatidylserine and no protein like so-called proteolipid-protein in comparison with the total chloroform-methanol (2:1, v/v) extract of myelin. Thus, the propanol-hexane myelin residue was re-extracted with chloroform-methanol (2:1, v/v) and the extract was subjected to UV-spectroscopy, TLC and slab SDS-gel electrophoresis, respectively. The UV-absorption pattern of the extract showed a maximum band due to protein at about 280 nm. The lipid portion was found to be predominantly sulfatide (63.6%), phosphatidylserine (26.2%) and other lipids (10.2%), while the major portion of protein was basic protein. The amino acid composition of the extract was also very similar to that of a control porcine basic protein. The major normal fatty acids of sulfatide were C24:0 (34.5%), C24:1 (13.7%), C23:0 (8.3%) and C18:0 (16.0%), while the hydroxy acids were predominantly C24:0 (44.1%), C24:1 (22.2%) and C23:0 (10.4%). Also, the fatty acids of phosphatidylserine were mainly C18:0 and C18:1. The solubilization of the basic protein-acidic lipid complex (about 2.56 by weight in the ratio of protein to lipid) in chloroform-methanol suggested the interaction of the basic protein with acidic lipids which might be related to the molecular organization in myelin. The basic protein-acidic lipid complex was also found to have an encephalitogenic activity which seemed to be a little different from that of basic protein itself.
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Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.