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951.
952.
Summary The present study elucidated that N-CWS augments the cytolytic activity against 3LL tumor cells of LAK cells from N-CWS-immunized mice administered i.p. with rIL-2. This augmentative effect of N-CWS was not seen when the LAK cells were prepared from normal mice. The cytolytic activity was predominantly expressed in the NAPC prepared from the site of injection of rIL-2, and repeated administrations of rIL-2 were required to induce and maintain this potent cytolytic activity in vivo. Serological analysis revealed that the LAK cells were positive for Thy 1.2 and asialo GM1 antigens and that they were not classical CTL or NK cells. The administration of rIL-2 statistically prolonged the MST of mice bearing LAK-sensitive 3LL cells but not the MST of mice bearing LAK-resistant EL-4 leukemia. Furthermore, combination therapy with N-CWS and rIL-2 prolonged the MST of the mice more than the therapy with rIL-2 alone. These results suggest that LAK cells potentiated with N-CWS would be useful for immunotherapy of malignant neoplasms. Abbreviations used: N-CWS, Nocardia rubra cell-wall skeleton; rIL-2, recombinant interleukin 2; LAK, lymphokine-activated killer; RPMI 1640, Roswell Park Memorial Institute 1640; FCS, fetal calf serum; TCM, tumor culture medium; PC, peritoneal cells; NAPC, nonadherent PC; APC adherent PC; MST, mean survival time; NK, natural killer; E:T ratios, effector to target ratios; Poly I:C, polyinosinic-polycytidylic acid; CTL, cytotoxic T lymphocytes; RLNC, regional lymphnode cells  相似文献   
953.
Summary The ability of Nocardia rubra cell wall skeleton (N-CWS) to augment macrophage cytotoxicity function was examined using human pleural macrophages prepared from 32 malignant pleural effusions and 53 pleural washings. The cytostatic activity of pleural macrophages for human lung cancer cells (PC-9) was augmented following incubation of pleural mononuclear cells with 10 g/ml N-CWS for 24 h. Macrophage activity was increased by direct interaction of macrophages with N-CWS or by incubation of macrophages with supernatant culture fluids from pleural lymphocytes with N-CWS. The cytotoxic potential of the pleural macrophages obtained from patients treated with 500 g of N-CWS intrapleurally was also increased. The heat and acid stability studies revealed that the culture fluids from pleural lymphocytes treated with N-CWS contained macrophage activation factor in addition to interferon-. These results suggest that direct and indirect macrophage activation is part of the mechanism in which N-CWS has a clinical effect on malignant pleural effusions.  相似文献   
954.
The conjugate pattern of biliary [14C]bile acids was investigated in isolated perfused rat livers, which were infused with either [24-14C]cholic acid or [24-14C]chenodeoxycholic acid (40 mumol/h) together with or without taurine or cysteine (80 mumol/h). [14C]Bile acids were chromatographed on a thin-layer plate and the distribution of radioactivity on the plate was measured by radioscanning. The biliary excretion of [14C]bile acids was greater in the infusion with [14C]cholic acid than in the infusion with [14C]chenodeoxycholic acid. Biliary unconjugated [14C]bile acids amounted to about 50% of the total after the infusion with [14C]cholic acid, while only about 10% with [14C]chenodeoxycholic acid. In the initial period of infusion, biliary conjugated [14C]bile acids consisted mostly of the taurine conjugate, which decreased with time and the glycine conjugate increased complementarily. When taurine was simultaneously infused, the decrease in the taurine conjugate was suppressed to some extent. Cysteine infused in place of taurine had a similar influence but was less effective than taurine. The taurine content of liver after the infusion with either of the [14C]bile acids decreased greatly compared with that before the infusion, even when taurine or cysteine was infused simultaneously. The glycine content also decreased after the infusion, but the decrease in glycine was smaller than that in taurine. The results suggest that the conjugate pattern of biliary bile acids in rats depends mainly on the amount of taurine which is supplied to hepatic cells either exogenously from plasma or endogenously within themselves.  相似文献   
955.
Human blood monocytes activated to the tumoricidal state were previously found to release a factor(s) responsible for tumor cell killing. The activity of the tumor cytotoxic factor(s) (TCF) was determined by release assay of radioactivity from human A375 melanoma cells. On fractionation of the supernatant of activated monocytes by Ultrogel AcA34 and TSK-G3000SW gel chromatographies two major peaks of the material with TCF activity with MWs of 30,000 and 15,000, called TCF-I and TCF-11, respectively were obtained. TCF-II could be neutralized by polyclonal anti-IL-1 antiserum, but anti-IL-1 antiserum did not neutralize either factor. TCF-I was separated by ampholine column electrofocusing into three major fractions with TCF activity at pI 5, 6 and 6.8, named TCF-1, TCF-1 and TCF-1, respectively. The cytotoxic and IL-1 activities of TCF-1 were neutralized by anti-IL-1 serum, whereas those of TCF-1 and TCF-1 were not completely neutralized by anti-IL-1 or anti-IL-1 antiserum. On DEAE ion-exchange chromatography (TSK DEAE 5PW) TCF-I gave two peaks with TCF activity (TCF-I1 and TCF-I2). TCF-I1 was slightly neutralized by anti-TNF antibody, but TCF-I2 was not affected by antisera against IL-1 and IL-1, or anti-TNF antibody, thus ruling out the possibility that tumor necrosis factor (TNF) might be involved in tumor cell killing mediated by TCF-I2. These results indicate that human monocyte-mediated cytotoxicity against human A375 melanoma cells is mediated in part by a tumor cytotoxic factor (TCF; MW, 30,000; pI 6), differing from IL-1 and TNF.  相似文献   
956.
Ten strains of Pseudomonas aeruginosa were disrupted and centrifuged. The supernatant fluids from centrifugation at 105,000 × g contained enzymes inactivating kanamycin, neomycin, and streptomycin in the presence of adenosine triphosphate. Kanamycin-inactivating enzyme was precipitated with ammonium sulfate at 66% of saturated concentration, and the inactivated kanamycin was shown to be kanamycin-3′-phosphate in which the C-3 hydroxyl group of 6-amino-6-deoxy-d-glucose moiety was phosphorylated. This is identical with kanamycin inactivated by Escherichia coli carrying R factor. Streptomycin-inactivating enzyme was precipitated with ammonium sulfate at 33% of saturated concentration.  相似文献   
957.
958.
Pith-derived calluses of Nicotiana tabacum L. cv. Wisconsinno. 38 were inoculated on an RM-1964 medium containing variousconcentrations of a morphactin, chlorflurenol (CFl) and kinetin(KIN). An addition of KIN (0.1–2 mg/liter) alone was effectivefor shoot formation from the calluses, but a high dose (10 mg/liter)resulted in the inhibition of growth and in no differentiation.The inhibitory effect of a high dose of KIN was counteractedwith CFl. Three combinations of KIN and CFl; CFl (0.1 mg/liter)$KIN(2.0 mg/liter); CFl (0.1 mg/liter)$KIN (10.0 mg/liter) and CFl(1.0 mg/liter) $KIN (2.0 mg/liter), were successful for 100%shoot redifferentiation in inoculated calluses. An appropriatebalance between CFl and KIN seems to be involved in shoot formation.The present results can best be interpreted by assuming thatCFl acts as an auxin in cultured tissues. (Received January 16, 1975; )  相似文献   
959.
Firstly, a collective oscillation mode of the neural activity is derived from the neural network system by using the multicompartment equation and the projection operator technique. This technique takes into account higher order interactions among neurons. The solution of the equation gives a chain structure with an infinite number of circuit loops in which each of them is only composed of four neurons. The obtained eigenvalues are quite similar to the spectrum of frequencies of the EEG. Secondly, the time-dependent behavior of the observed EEG is simulated by starting from the elementary process of action potential trains of neurons, which includes the effect of the collective oscillation mode mentioned above. This gives a comprehensive derivation of the EEG from the neural activity of action potentials. The simulation assumes that information of the action potential trains can be transmitted to the EEG through the intermediate states of the postsynaptic potential trains and the slow waves. The paper reports that a slightly modulated activity of a relatively small amount of neurons can cause a strong influence on the shape of the global EEG and that the calculated results reproduce the characteristic features of the EEG in a rat such as the theta rhythm, the spindle wave and the arousal wave.  相似文献   
960.
The microsomes from pig liver contained farnesyl pyrophosphate synthetase and it was solubilized with Triton X-100. The microsomal enzyme had a pH optimum of 6.5-7.0 and required Mg2+ or Mn2+ for maximum activity. Dimethylallyl-transferring activity of the enzyme was much lower compared with the geranyl-transferring activity. In the presence of Triton X-100, the geranyl-transferring activity was about two-fold activated whereas the dimethylallyl-transferring activity was almost the same.  相似文献   
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