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41.
Purification and characterization of a tuberculin-active substance from Mycobacterium bovis BCG 总被引:1,自引:0,他引:1
A new tuberculin-active substance, designated TAS-1D3, has been purified from the extract of Mycobacterium bovis BCG by precipitation at pH 4.2, ethanol fractionation, and column chromatography involving CM-cellulose, QAE-Sephadex A-25, Sephadex G-100, and Sephadex G-75. TAS-1D3 was homogeneous in polyacrylamide gel electrophoresis and positive in both Coomassie brilliant blue and periodic acid-Shiff staining, suggesting that TAS-1D3 is a glycoprotein. The molecular weight of TAS-1D3 was estimated to be 26,000 by gel filtration. In amino acid analysis, TAS-1D3 was distinctive in having proline as a dominant amino acid, and in that it lacked basic amino acids, sulfur-containing amino acids and aromatic amino acids. Moreover, TAS-1D3 was almost devoid of absorption at around 280 nm. In guinea pigs sensitized with BCG vaccine, the tuberculin activity of TAS-1D3 was about forty times more potent than that of purified protein derivative (PPD). 相似文献
42.
Antigen presentation by human antigen-presenting cells to antigen-specific xenogeneic murine T cells
Successful antigen presentation by xenogeneic human antigen-presenting cells (APC) to stimulate the proliferation of antigen-specific, keyhole limpet hemocyanin (KLH)-specific, ovalbumin (OVA)-specific, and purified protein derivative of Mycobacterium tuberculosis (PPD)-specific murine T cells was observed. Evidence indicating a direct cell interaction between antigen-specific murine T cells and xenogeneic human APC was given by experiments using antigen-specific murine T cell clones. The OVA-specific B10.S(9R) T cell line (9-0-A1) and PPD-specific B10.A(4R) T cell line (4-P-1) were stimulated by both xenogeneic human APC and murine APC from syngeneic or I-A compatible strains, while the PPD-specific human T cell line (Y-P-5) was stimulated by autologous human APC but not by murine APC. Anti-HLA-DR monoclonal antibodies (MoAb) blocked the xenogeneic human APC-antigen-specific murine T cell clone interaction. Thus, human xenogeneic APC can stimulate antigen-specific murine T cells through HLA-DR molecules in the same manner as syngeneic murine APC do through Ia molecules coded for by the I region of the H-2 complex, while murine APC failed to present antigen to stimulate human antigen-specific T cells. 相似文献
43.
Estimates of Denitrification and Nitrification in Coastal and Estuarine Sediments 总被引:13,自引:5,他引:8 下载免费PDF全文
Denitrification and nitrification in sediments of Tama Estuary and Odawa Bay, Japan, were investigated by the combined use of a continuous-flow sediment-water system and a 15N tracer technique. At Odawa Bay, the nitrification rate was comparable to the nitrate reduction rate, and 70% of the N2 evolved originated from nitrogenous oxides (nitrate and nitrite) which were produced by the action of nitrifying bacteria in the sediments. At Tama Estuary, the nitrate reduction rate was 11 to 17 times higher than the nitrification rate, and nitrogenous oxides derived from ammonium accounted for only 6 to 9% of the N2 evolution by denitrification. 相似文献
44.
Isolation and characterization of a third proteoglycan (PG-Lt) from chick embryo cartilage which contains disulfide-bonded collagenous polypeptide 总被引:11,自引:0,他引:11
A Noro K Kimata Y Oike T Shinomura N Maeda S Yano N Takahashi S Suzuki 《The Journal of biological chemistry》1983,258(15):9323-9331
Chick embryo epiphyseal cartilage has been shown to contain three different proteoglycan species (PG-H, PG-Lb, and PG-Lt). This report is concerned with the purification and characterization of the third proteoglycan, PG-Lt. The proteoglycan can be separated from the other two by virtue of its low buoyant density in a CsCl density gradient and further purified by consecutive ion exchange and gel chromatography. The final preparation is composed of PG-Lt monomer and PG-Lt oligomer. The amino acid composition of PG-Lt is quite different from that of PG-H and PG-Lb and rather resembles that of collagens with respect to high content of glycine and high degrees of hydroxylation of proline and lysine. PG-Lt monomer is composed of disulfide-bonded subunits of Mr congruent to 120,000 and 190,000 as demonstrated by its gel electrophoretic behavior after reduction with 2-mercaptoethanol. The latter, but not the former, contains dermatan sulfate chains with glucuronic acid/iduronic acid residues and yields a protein-enriched core molecule of Mr congruent to 100,000 after digestion with chondroitinase ABC. Both of the protein subunits are completely digestible with bacterial collagenase. Immunofluorescence microscopic examination of cartilage tissues, using an antibody against PG-Lt, shows that this proteoglycan exists in both the cartilage matrix and perichondrial noncartilagenous region. When chondrocytes are plated onto tissue culture dishes, the antibody stains strands found on the cell surfaces and in the intercellular space of substrate-attached cell layers, suggesting that PG-Lt mediates cell-to-cell and cell-to-substrate contacts. 相似文献
45.
Shoei Furukawa Isao Kamo Yoshiko Furukawa Saeko Akazawa Eijiro Satoyoshi Koji Itoh Kyozo Hayashi 《Journal of neurochemistry》1983,40(3):734-744
Abstract: A sensitive two-site enzyme immunoassay system for mouse β nerve growth factor (NGF) was developed, based on the sandwiching of the antigen between anti-mouse β NGF antibody IgG coated to a polystyrene tube and anti-mouse β NGF antibody Fab'-linked β- d -galactosidase (β- d -galactoside hydrolase, EC 3.2.1.23). This method has the following advantages: (a) the procedures are simple and rapid compared to bioassay or two-site radioimmunoassay; (b) antibody Fab'-β- d -galactosidase complex is more stable than 125 I-labeled antibody; (c) purified β NGF is detectable at a concentration as low as 10 pg/ml. Our enzyme immunoassay was used to examine the levels of NGF in some tissues of mice. The submaxillary gland contained a high concentration of NGF. However, other tissues, such as the heart, brain, and skeletal muscle, and serum did not contain detectable NGF. These results support recent findings by other investigators that NGF was not found in the organs/tissues other than the submaxillary gland of mice. 相似文献
46.
Effects of ingested phytoecdysteroids on the growth and development of two Lepidopterous larvae 总被引:1,自引:0,他引:1
The effects of ingested or injected 20-hydroxyecdysone on silkworm larvae (Bombyx mori) including death without moulting, death following completion of promoted moulting, death during promoted moulting (ecdysis inhibition) and inhibition in growth with and without effects on moulting, are dependent upon the concentration of exogenous hormone, the precise developmental stage of the treated larvae, and the duration of exposure to the exogenous ecdysteroid. Comparisons of 20-hydroxyecdysone with other phytoecdysteroids in the silkworm and pink bollworm, Pectinophora gossypiella, show a similar but more potent effect induced by ponasterone A, while cyasterone causes an ‘antiecdysone’ effect. 相似文献
47.
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49.
T. Hamazaki S. Fischer M. Urakaze S. Sawazaki S. Yano T. Kuwamori 《Prostaglandins & other lipid mediators》1989,37(4)
Epidemiological studies were performed in a Japanese fishing village when catches of fish were highest and in a Japanese farming village with usual fish consumption. Intake of eicosapentaenoic, docosahexaenoic and also arachidonic acid were significantly higher in the fishing village during the 3 days of the study than in the farming village. The correlation between eicosapentaenoic acid intake on the day when urine was collected and excreion of Δ 17-2,3-dinor-6-keto-prostaglandin F1α, the main urinary metabolite of prostaglandin I3, was highly significant, whereas there was no correlation between arachidonic or linoleic acid intake and excretion of 2,3-dinor-6-keto-prostaglandin F1α, the main urinary metabolite of prostaglandin I2. We suggest that the arachidonic acid pool for prostaglandin I2 production is not quickly influenced by dietary linoleic or arachidonic acid because of a large pool size of arachidonic acid and a slow conversion of linoleic acid to arachidonic acid, while prostaglandin I3 formation is directly related to the intake of eicosapentaenoic acid. 相似文献
50.
Antigens, recognized by human monoclonal antibody (HB4C5) generated from a lung cancer patient, were found to occur in porcine pancreas. The antigens-I and -I1 were purified from crude trypsin of porcine pancreas, only by Mono Q column chromatography, and were eluted at 260 and 300 mM NaCl in 10 mM Tris-HCI buffer, pH 7.4, respectively. These antigens differed from trypsin in molecular weight, elution pattern from the Mono Q column, and their reactivity with HB4C5. The molecular weights of the two antigens were almost the same at around 35000. These were used for serodiagnosis with an assay system based on 96-well immunoplates. The reactivities of antigens-I and -II with various sera were similar. When the reactivity of IgG in serum with antigen-II was measured, absorbance at 415 nm in the case of normal and lung cancer patients was 0.178 ± 0.056 and 0.492 ± 0.136 (p < 0.005). The rates of positive reaction in ovary, larynx, uterus, lung and liver cancers were more than 50%, but the rates in stomach and breast cancers were less than 30%. Positive reaction was hardly detected in pancreas cancer and normal controls. 相似文献