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1.
R Uchino T Nohara E Okamoto M Fukumoto O Midorikawa 《Virchows Archiv. B, Cell pathology including molecular pathology》1985,48(3):229-236
A cloned human hepatoma cell line (HH2-1) produced and formed collagen fibers in vitro. The relative rate of collagen synthesis by the cells was increased with an enhancement of the cell density. An analysis of the components of the collagen using sodium dodecyl sulfate-polyacrylamide gel electrophoresis revealed that the cells synthesized interstitial collagen, types I and III, and other collagenous proteins. Thus, human hepatoma cells may play an important role in the formation of stromal collagen in the tumor. 相似文献
2.
Distribution of spermine in bacilli and lactic acid bacteria 总被引:1,自引:0,他引:1
Obligate moderately thermophilic bacilli and obligate moderately thermoacidophilic bacilli contained spermine as the major polyamine in addition to putrescine and spermidine. The identity of spermine was confirmed by thin-layer chromatography and high-performance liquid chromatography before and after treatment with putrescine oxidase. Using these methods, thermospermine and spermine can be separated; thermospermine was not present in these organisms. On the other hand, various facultative thermophiles and mesophilic strains of the genus Bacillus, including alkalophiles and halophiles, lack spermine and other tetraamines. No spermine was detected in several strains of mesophilic or facultative slightly thermophilic lactic acid bacteria, Lactobacillus and Streptococcus. 相似文献
3.
Yuzuru Mikami Sen Feng Yu Katsukiyo Yazawa Kazutaka Fukushima Akio Maeda Jun Uno Kiyoshi Terao Naoki Saito Akinori Kubo Ken -ichiro Suzuki 《Mycopathologia》1990,112(2):113-118
During our studies on toxic substances from clinically isolated Nocarida, a new isolate identified as Nocardia otitidiscaviarum from cutaneous nocardiosis was found to produce a toxic substance called HS-6 that had strong in vitro as well as in vivo toxicity. The mouse intraperitoneal LD50 value was 1.25 mg/kg and the ED50 value for L1210 cultured cells was 0.3 ng/ml. The structure of HS-6 was determined and found to belong to the 16-membered macrocyclic group with a molecular formula of C43H68O12. HS-6 also showed activity against pathogenic fungi such as Cryptococcus neoformans. 相似文献
4.
Isogai Akira; Takayama Seiji; Shiozawa Hideyuki; Tsukamoto Chise; Kanbara Takeshi; Hinata Kokichi; Okazaki Keiichi; Suzuki Akinori 《Plant & cell physiology》1988,29(8):1331-1336
S-Glycoproteins (S-locus-specific glycoproteins) in Brassicaspecies are present only in stigmas and thought to play an importantrole in self-incompatibility system. The stigma extract containsalso several other glycoproteins reacting with the antiserumto S-glycoproteins, among which some glycoproteins from S8S8-and S9S9-homozygotes have the same pI value. Both of the glycoproteinswhich were tentatively termed NS8- and NS8S9-glycoproteins,respectively, were isolated and analyzed. Those were revealedto be identical. Its amino acid sequence was homologous withthe S-glycoproteins in Brassica species. The NS-glycoproteinswere expressed at the same time and only in stigma as S-glycoproteins. (Received July 19, 1988; Accepted September 7, 1988) 相似文献
5.
We previously reported that human promyelocytic leukemia HL-60 cells, when treated with various inducers in magnesium-deficient medium, became committed to differentiate but did not express the differentiation-related phenotypes (Okazaki et al., J. Cell. Physiol., 131:50-57, 1987). In the present study we demonstrated the existence of an intracellular differentiation-inducing activity (int-DIA) in differentiation-committed phenotype-nonexpressing HL-60 cells by using cybrid formation between untreated HL-60 cells and cytoplasts from HL-60 cells treated in magnesium-deficient medium with 100 nM 1 alpha,25-dihydroxyvitamin D3 (1,25(OH)2D3). Cell extracts from similarly treated HL-60 cells also showed int-DIA, which when added (10 mg total protein/ml) to culture of untreated HL-60 cells, could increase the percentages of nitroblue tetrazolium (NBT)- and nonspecific esterase (NSE)-positive cells from 1% to 53%, and from 0 to 32%, respectively. They also induced differentiation of human monoblastic leukemia U-937 cells and of human myeloblastic leukemia KG-1 cells but not of erythroleukemia K-562 cells. These results suggested that the int-DIA had a common effect on differentiation induction in several human myeloid cell lines and may be involved in inducing cells to proceed from a commitment to a phenotype-expression step during human myeloid cell differentiation. 相似文献
6.
c-Hc-4 has been established and maintained for more than seven years. The hepatocellular carcinoma originated in 45-year old man with liver cirrhosis. The cell grew in vitro forming a sheet of monolayered cells and firmly attaching to the inner surface of cultured flasks. Morphologically they showed epithelial-like pattern. The doubling time was about 20 hours. Their modal chromosome number was 58. Serial heterologous transplantation in nude mice was successful. The histological finding was almost the same patterns as those in the primary tumor. The cultured cells produced alpha-fetoprotein (AFP) and carcinoembryonic antigen (CEA). 相似文献
7.
Kenji Kanaji Minoru Okuma Fumitaka Ushikubi Haruto Uchino 《Prostaglandins, leukotrienes, and essential fatty acids》1988,31(3):155-161
Lipoxygenase activities were estimated in washed platelets (intact platelets) and their subcellular fractions obtained from 7 patients with deficient platelet lipoxygenase activities and 9 normal subjects. From sonicated platelet preparations, 12,000 g supernatant (F-I), cytosol (F-II) and microsomal fractions (F-III) were prepared by differential centrifugation. When 12-hydroxyeicosatetraenoic acid (12-HETE) produced by the incubation of arachidonic acid with intact platelets or each of their subcellular fractions from normal subjects was measured by reversed-phase high-performance liquid chromatography analysis, the lipoxygenase activities of F-I, F-II and F-III were 87%, 31% and 17%, respectively, of the enzyme activity of intact platelets. One of the patients showed no detectable lipoxygenase activity in any preparation, while the other patients showed reduced enzyme activities in all preparations. The addition of CaCl2 significantly increased 12-HETE synthesis solely by F-I from these patients. In most of these patients, contrary to normal subjects, it appeared that the lipoxygenase activity was not fully expressed in intact platelets, since the F-I produced more 12-HETE than the intact platelets. 相似文献
8.
Growth and Aspartate Kinase Activity in Wheat Cell Suspension Culture: Effects of Lysine Analogs and Aspartate-Derived Amino Acids 总被引:1,自引:0,他引:1
Yamada Yasuyuki; Kumpaisal Rosarin; Hashimoto Takashi; Sugimoto Yukihiro; Suzuki Akinori 《Plant & cell physiology》1986,27(4):607-617
The effects of lysine analogs and aspartate-derived amino acidson the growth of wheat cell suspension culture were studied.S-(2-Aminoethyl)-L-cysteine (AEC), -hydroxylysine (DHL) andtrans-lysene caused complete growth inhibition at 1.0 mM. Thegrowth inhibition of lysine analogs were, in the order of decreasingeffectiveness; AECDHL, trans-lysene>oxalysine, homolysineand lysyne. cis-Lysene and methyllysine were not inhibitoryeven at concentrations of 10 mM. Lysine effectively relievedgrowth inhibition induced by the lysine analogs. Lysine plusthreonine showed concerted inhibition, which was relieved bythe addition of methionine. Activity of aspartate kinase extracted from wheat cell suspensionculture was strongly inhibited by L-lysine; 0.75 to 1 mM oflysine was required for half-maximal inhibition. Threonine andmethionine, individually or in combination with lysine, showedno inhibitory effect on the enzyme activity. S-Adenosylmethionine,when added with lysine in equimolar concentrations, enhancedthe feedback inhibition by lysine, lowering the concentrationof lysine for half-maximal inhibition to 0.13 mM. The aspartatekinase isolated from the cells cultured in the presence of 5mM lysine did not differ in regulatory properties from the enzymefrom the cells cultured without lysine. AEC at 5 mM inhibitedthe enzyme activity by 50%. Other lysine analogs were not inhibitoryto the enzyme activity even at 10 mM. Growth inhibition of wheat suspension culture by aspartate-derivedamino acids and lysine analogs were discussed in relation totheir inhibitory effects on aspartate kinase activity. (Received October 25, 1985; Accepted February 26, 1986) 相似文献
9.
Yutaka Suzuki Yoshiteru Harada Akinori Ueno Makoto Katori Haruya Okabe 《Prostaglandins & other lipid mediators》1986,32(3)
Filling of the gastric lumen of rats with 1.0 M NaCl solution (5 ml) for 10 min under urethane anesthesia caused an increase in the gastric fluid concentrations of prostaglandin (PG) E2, 13, 14-dihydro-15-keto-PGE2 and 6-keto-PGF1α as determined by radioimmunoassay. PGE2 was the major PG generated. The levels of PGE2 in the gastric fluid were increased dose-dependently after filling the lumen with 0.3, 0.5, 0.7 or 1.0 M NaCl solutions. The pH of the gastric fluid increased similarly after 0.5 to 1.0 M NaCl solutions. Indomethacin (10 mg/kg, i.p.) suppressed the PGE2 increase caused by 1.0 M NaCl solution, but did not prevent the increase of the pH of the gastric fluid induced by intragastric 1.0 M NaCl. Infusion of tetragastrin (62.5 μg/kg/hr, i.v., for 10 min) caused a marked increase of acid secretion without modifying intragastic concentration of PGE2. The acid secretion due to tetragastrin was completely inhibited after intragastric administration of 1.0 M NaCl solution, while indomethacin restored the tetragastrin-induced acid secretion, with prevention of a rise of intragastric PGE2 levels. These observations suggest that 1.0 M NaCl solutions suppress basal intragastric acid through a mechanism which is independent of prostaglandins. In contrast, the suppression of tetragastrin-induced acid secretion by intragastric 1.0 M NaCl solution appears to be mediated through a release of prostaglandins 相似文献
10.
Specific cytolysis of fresh tumor cells by an autologous killer T cell line derived from an adult T cell leukemia/lymphoma patient 总被引:8,自引:0,他引:8
M Kannagi K Sugamura K Kinoshita H Uchino Y Hinuma 《Journal of immunology (Baltimore, Md. : 1950)》1984,133(2):1037-1041
Cytotoxic T cells (Tc) derived from one patient with adult T cell leukemia/lymphoma (ATL) killed fresh autologous lymphoma cells in vitro. The Tc were induced from peripheral blood leukocytes (PBL) of this patient during remission by multiple in vitro stimulations with an autologous ATLV-bearing cell line (ILT) that was previously established by cloning of PBL in the presence of interleukin 2 (IL 2). PBL from eight other ATL patients were stimulated in the same manner, and responder cells from a patient in remission also showed cytotoxicity specific for ATL virus (ATLV)-bearing cells. Fresh lymphoma cells were obtained in relapse and were used as target cells for the autologous Tc induced. They became susceptible to the Tc within 4 hr of in vitro incubation, and their susceptibility increased with incubation time for at least 12 hr. ATLV antigens on the cell surface of these lymphoma cells, however, were not detected by radioimmunoassay during these incubation periods, but were detectable after 16 hr of incubation. In addition, cytotoxicity against lymphoma cells was completely inhibited by autologous ILT cells used as "cold" target competitor cells. These findings indicate that the target antigen of the Tc was expressed on both autologous ILT cells and lymphoma cells, and it may be different from ATLV antigens detected by serologic methods. In addition, the data suggested allogeneic restriction of the Tc in that the preferentially killed allogeneic ATLV-bearing cells share several HLA antigens. 相似文献