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21.
In the present study, anti-metastatic effect of Z-100 on the spontaneous pulmonary metastases of Lewis lung carcinoma (3LL) was examined in an attempt to regulate suppressor T cells. When Z-100 (10 mg/kg) was daily injected i.p. after 3LL inoculation, survival rate of these mice was increased significantly (p<0.05). In addition, the number of pulmonary metastatic colonies of 3LL in Z-100-treated mice were significantly decreased by 38% at 21 days, as compared with that of control mice (p<0.05). Along with the decrease of pulmonary metastases, suppressor cell activity was also gradually reduced in these mice, as compared with that of control mice. When splenic suppressor cells (5×107 cells) from 3LL-bearing mice were adoptively transferred into normal mice (recipients) just before inoculation of 3LL, the development of pulmonary metastases in recipients was significantly accelerated. However, splenocytes from 3LL-bearing mice treated with Z-100 did not affect the development of pulmonary metastasis. The potential to accelerate the metastasis of splenic mononuclear cells from 3LL-bearing mice was decreased significantly by the treatment with anti-Thy 1.2 monoclonal antibody (mAb), anti-Lyt 2.2 mAb or anti-CD11b mAb followed by complement. IL-4 activity in the sera of 3LL-bearing mice was detected 15 days after tumor inoculation (13 pg/ml) and gradually increased (18 pg/ml) 20 days after tumor inoculation. However, when Z-100 (10 mg/kg) was daily injected i.p., IL-4 activity in sera was decreased significantly, and the IL-4 activity was not detected in these mice on day 20. These results suggest that Z-100 could inhibit the pulmonary metastases in 3LL-bearing mice through the inhibition of suppressor T cell activity and a possible candidate of its effector molecule, IL-4.  相似文献   
22.
The growth of MethA tumor was significantly inhibited by oral administration of the -glucan SPR-901 in BALB/c (+/+) mice but not in nude mice. Mice treated orally with SPR-901 exhibited an augmentation of antigen-specific resistance against rechallenge with the tumor cells. The tumor-neutralizing activity of regional lymph node cells from MethA-bearing mice against the tumor was augmented by oral administration of SPR-901. The tumor-neutralizing activity of lymph node cells from SPR-901-treated mice mainly appeared in Lyt2+cells. Furthermore, lymphokine-activated killer activity of these cells was enhanced by administration of SPR-901. The antitumor effect of SPR-901 was abrogated in mice depleted of either L3T4+ or Lyt2+ cells, and in cyclosporin-A-treated mice. These results suggest that Lyt2+ cells are important effector cells in MethA-bearing mice orally adminstered SPR-901 and that functional exertion of both Lyt2+ and L3T4+T cells is necessary for the antitumor effect of orally administered SPR-901 in vivo.  相似文献   
23.
The interfering effects of copper, zinc, and cobalt on the uptake of mugineic acid-ferric complex were studied in barley ( Hordeum vulgare , cv. Minorimugi) grown in nutrient solution. Short-term uptake experiments of 3 h were performed utilizing both ionic and mugineic acid-complex forms of each metal at two different concentrations. Copper was most effective in decreasing iron uptake when added in an ionic form at either concentration. The inhibition order at higher concentrations followed Cu(II) > Zn(II) ≥ Co(II), Co(III), which is consistent with the stability constants of these metal complexes with mugineic acid. The displacement of iron from its mugineic acid complex by these metals is suggested as a probable explanation for the decreased iron uptake. The inhibitory effect of metal complexes with mugineic acid on iron uptake was only found in cases with higher concentrations of Cu(II) and Zn(II) complexes. Deformation of the specific iron transport system in the plasma membrane due to their adsorption may be responsible for this effect.  相似文献   
24.
Five patients with common variable immunodeficiency treated in our hospital between December 1979 and December 1990 were given six kinds of intravenous immunoglobulin preparations (pepsin treated, S-sulfonated, polyethylene glycol treated, pH4 treated, alkylated, and pH4.25 formulation preparation) for replacement therapy. Duration of the therapy ranged from 7.6 to 11 years. Incidences of fever and acute infections were variable among patients, but no significant differences were seen in the incidences among periods given each preparation. Three cases revealed abnormal pulmonary functions in tests. Adverse reactions were rarely seen in our study periods, and no severe reactions were observed. No significant differences were seen in incidences of adverse reactions. Postinfusion levels of serum complement slightly decreased from preinfusion levels. However, the decrease in complement was not related to any adverse reaction. No long-term complications such as transmission of hepatitis have been observed. Our data suggest that no obvious differences exist between the efficacy and safety of each IVIG preparation. Differences of efficacy of IVIG replacement therapy may be due to the variable pathophysiology of each patient.Abbreviations CVID common variable immunodeficiency - IVIG intravenous immunoglobulin  相似文献   
25.
In vitro 5-day cultures of naive spleen cells with viable Listeria monocytogenes (VLM), but not heat-killed L. monocytogenes, induced CD4+ T cells that produced IFN-γ upon secondary antigen stimulation. The VLM-induced Listeria-specific T cells produced IFN-γ but lacked expression of IL-2 and IL-4. To study the role of IFN-γ in the induction of the IFN-γ-producing T cells, we added anti-IFN-γ mAb to the primary culture and analyzed IFN-γ production upon secondary antigen stimulation. Addition of anti-IFN-γ mAb to the culture suppressed generation of IFN-γ-producing CD4+ T cells, suggesting that IFN-γ is important in the induction of IFN-γ-producing CD4+ T cells. Furthermore, our results showed that depletion of NK cells from spleen cells by anti-asialo GM1 antibody plus complement before culture enhanced induction of IFN-γ-producing CD4+ T cells. Although NK cells are known to produce IFN-γ, the results indicate that NK cell-derived IFN-γ may not be important in induction of the Listeria-specific IFN-γ-producing CD4+ T cells in the culture system. In addition, we demonstrated that IFN-γ expression was high in CD4+ T cells from cultures of spleen cells with VLM at the primary culture level. These results suggest that IFN-γ derived from T cells may enhance production of IFN-γ by CD4+ T cells, while NK cells rather suppress the induction of IFN-γ-producing CD4+ T cells.  相似文献   
26.
Most poliovirus strains infect only primates. The host range (HR) of poliovirus is thought to be primarily determined by a cell surface molecule that functions as poliovirus receptor (PVR), since it has been shown that transgenic mice are made poliovirus sensitive by introducing the human PVR gene into the genome. The relative levels of neurovirulence of polioviruses tested in these transgenic mice were shown to correlate well with the levels tested in monkeys (H. Horie et al., J. Virol. 68:681-688, 1994). Mutants of the virulent Mahoney strain of poliovirus have been generated by disruption of nucleotides 128 to 134, at stem-loop II within the 5' noncoding region, and four of these mutants multiplicated well in human HeLa cells but poorly in mouse TgSVA cells that had been established from the kidney of the poliovirus-sensitive transgenic mouse. Neurovirulence tests using the two animal models revealed that these mutants were strongly attenuated only in tests with the mouse model and were therefore HR mutants. The virus infection cycle in TgSVA cells was restricted by an internal ribosomal entry site (IRES)-dependent initiation process of translation. Viral protein synthesis and the associated block of cellular protein synthesis were not observed in TgSVA cells infected with three of four HR mutants and was evident at only a low level in the remaining mutant. The mutant RNAs were functional in a cell-free protein synthesis system from HeLa cells but not in those from TgSVA and mouse neuroblastoma NS20Y cells. These results suggest that host factor(s) affecting IRES-dependent translation of poliovirus differ between human and mouse cells and that the mutant IRES constructs detect species differences in such host factor(s). The IRES could potentially be a host range determinant for poliovirus infection.  相似文献   
27.
Flames of flammable gases, when blown against a surface of an aqueous solution of organic compounds, were found to induce oxidation as well as other reactions in the solution. This reaction would be regarded as a new model for formation of bioorganic molecules in the primitive hydrosphere exposed to some radical-containing atmosphere.  相似文献   
28.
We determined the sequence of the 2,138 nucleotides in the Sendai virus genome just following the 3' proximal 3,686 nucleotides which we had previously reported (Nucleic Acids Res. 11, 7317-7330, 1983). This covers the entire third gene of 1,173 nucleotides and the 3' proximal 1,013 nucleotides of the fourth gene. Like the NP and P+C genes, both the third and fourth genes start from consensus sequence R1 (3'-UCCCAC(or UA)UUUC) at the 3' end and the third gene terminates with consensus sequence R2 (3'-AUUCUUUUU) at the 5' end. The third gene was identified as M, and the deduced 348 amino acids indicated that the M protein is rich in basic residues and has hydrophobic domains near the C-terminal. The fourth gene, although sequencing is not complete yet, was identified as F, since a large open reading frame found in the gene contains the characteristic sequence of 20 amino acids located at the N-terminal of the F1 protein. Analyses of the amino acid sequence suggested that the structure of the F gene product is NH2-signal peptide-F2-F1-COOH.  相似文献   
29.
Bacterial growth and lethality of Listeria monocytogenes in mice were augmented by carrageenan-treatment and X-irradiation (8 J kg-1), whereas growth and lethality of Pseudomonas aeruginosa were augmented by X-irradiation but not by carrageenan-treatment. Protection against L. monocytogenes, at least in the early phases, appears to depend mainly on macrophages, since carrageenan depletes macrophages but not polymorphonuclear cells (PMN), whereas protection against P. aeruginosa appears to depend mainly on PMN. Ineffectiveness of PMN in elimination of L. monocytogenes is supported by histological examination and observation of intracellular killing in vitro.  相似文献   
30.
Transformation-defective (td) mutants with different sizes of genomic RNA were isolated from the Prague strain of Rous sarcoma virus, subgroup C(PR-C). All six td viruses (tdTYPR-C) isolated from a single UV-irradiated stock of PR-C (clone 2 of TYPR-C) had slightly longer RNA than did the ordinary class b RNA of tdB77 and Rous-associated virus-7. td viruses spontaneously segregated in uncloned TYPR-C also contained genomic RNA of a size similar to tdTYPR-C RNA. On the other hand, two td mutants isolated from another stock of PR-C (LAPR-C) had the class b RNA. Fingerprint analysis confirmed that tdTYPR-C and tdLAPR-C were derived by deletion from clone 2 of TYPR-C and LAPR-C, respectively, and also showed that clone 2 of TYPR-C had sequences in its genome RNA different from those of LAPR-C, although it gave a fingerprinting pattern similar to the latter. These results strongly suggest that differences between the nucleotide sequences in TYPR-C and LAPR-C RNA may result in different extents of deletion.  相似文献   
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