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21.
N Kan S Yamasaki T Harada K Satoh Y Ichinose Y Moriguchi H Kodama K Ohgaki 《Human cell》1992,5(3):236-242
Among several approaches to augment the therapeutic effect of adoptive immunotherapy, we focused the antitumor synergy between transferred killer cells and host's fresh lymphocytes. Immunotherapy models using murine tumors or clinical experiments revealed that preadministration of immunostimulator such as OK-432, followed by chemotherapeutic agents such as cyclophosphamide, can induce host's non-cytotoxic fresh lymphocytes that act synergistically with cultured killer cells against autologous tumor cells. Immuno-chemo-lymphocytotherapy (a sequential treatment with OK-432, chemotherapy and adoptive immunotherapy) is useful to treat the patients with advanced cancer even if the number of transferred lymphocytes is limited. 相似文献
22.
Yoshiko Kubota Akihiro Shima 《Journal of comparative physiology. B, Biochemical, systemic, and environmental physiology》1991,160(6):621-625
Summary By using inbred strains (HO4C and HB32C) of the medaka,Oryzias latipes, the involvement of genetic factor(s) in the determination of thermoresistance of fish was investigated. The thermoresistance of embryos of the medaka was quantitated by the fraction of the embryos surviving 1 day after heat treatment. At early stages of development (st. 13 and st. 20–21), the HO4C strain was more resistant than the HB32C strain. At st. 20–21, the HO4C strain was more resistant than the HB32C strain at all temperatures used (42, 43, and 44°C). At later stages of development (st. 27 and st. 32), however, the HB32C strain was more resistant than the HO4C strain.The results of genetic cross experiments raised the following possibilities; the thermoresistance of embryos at early developmental stages can be lowered by some factor(s) inherited in the HO4C strain and/or increased by those in the HB32C strain. By contrast, the sensitivity of embryos at later stages of development was not affected by factor(s) of their parents, but by their own genetic constitution. 相似文献
23.
A phosphorylated analogue of DSIP at Ser7 has been shown to exist endogenously by immunochemical studies. An enzyme which could phosphorylate DSIP has not yet been identified. In the present study, we examined DSIP as a substrate for in vitro phosphorylation by casein kinase II. DSIP was phosphorylated by the enzyme with apparent Km and Vmax values of 20 mM and 90.9 nmol/min/mg protein, respectively. Both ATP and GTP were utilized as phosphoryl donors. Phosphorylation of DSIP was inhibited by heparin and enhanced by spermine. These results demonstrate that DSIP can serve as a possible substrate for casein kinase II in vitro. 相似文献
24.
Arteriovenous anastomoses (AVAs) participate in the regulation of blood flow. Although it has been speculated that AVAs in the dog's tongue play a role in the regulation of the body temperature, no published work is available on the structural characteristics of AVAs in the dog's tongue. The purpose of the present investigation was therefore to determine the frequency of AVAs and their structural characteristics by the fabrication of vascular corrosive resin casts and examination under a scanning electron microscope. This method permitted not only the visualization of the three-dimensional characteristics of AVAs, but also a clear differentiation between arterioles and venules. The total number of AVAs in the mucosal lamina propria of the dorsum of the left tongue half was 2,292. Several essential types such as S-shaped, hook-shaped, straight, bibranching and Y-shaped AVAs were observed, of which the S-shaped and similar types constituted the overwhelming majority; Y-shaped types have never been reported heretofore. This study also revealed that the locations where AVAs were most often distributed were, in descending order of frequency, the tip, the corpus and the root area of the tongue. This high frequency and strategic location of AVAs in the tongue strongly indicate that AVAs of the dog's tongue participate in the thermal regulation. 相似文献
25.
Cloning of a complete cDNA encoding human aromatase: immunochemical identification and sequence analysis 总被引:7,自引:0,他引:7
N Harada 《Biochemical and biophysical research communications》1988,156(2):725-732
A complete cDNA clone encoding a human aromatase was isolated from a human placental cDNA library in lambda gt11. An antibody to the polypeptide specified by the isolated clone was prepared, and Western blot analysis and antibody inhibition experiments of human placental aromatase activity confirmed the identification of the clone as aromatase cDNA. The isolated aromatase cDNA clone of 3030 bp with two unique EcoRI sites contained a 3'-noncoding region of 1397 bp, an open reading frame of 1509 bp encoding 503 amino acid residues, and a 5'-noncoding region of 124 bp. Analysis of the amino acid sequence of aromatase and comparison of aromatase with other forms of cytochrome P-450 indicated that this enzyme is a unique form of the cytochrome P-450 superfamily. 相似文献
26.
Suppression of overt diabetes in NOD mice by anti-thymocyte serum or anti-Thy 1, 2 antibody 总被引:7,自引:0,他引:7
Effects of anti-thymocyte serum (ATS) and anti-Thy 1, 2 monoclonal antibody on the spontaneously occurring diabetes in NOD mice were examined. Spontaneous diabetes in female mice was markedly suppressed by intravenous injection of rabbit anti-mouse thymocyte serum diluted to 1:4 on three consecutive days during the time period from 70 to 100 days after birth; the cumulative incidence of overt diabetes upto 195 days of age was greatly reduced and the onset of diabetes was delayed. Similar effect was observed with anti-Thy 1, 2 antibody treatment. These findings suggest that T lymphocytes play a role in the production of spontaneous diabetes in this mouse strain. 相似文献
27.
Glycinin A3B4 mRNA. Cloning and sequencing of double-stranded cDNA complementary to a soybean storage protein 总被引:8,自引:0,他引:8
C Fukazawa T Momma H Hirano K Harada K Udaka 《The Journal of biological chemistry》1985,260(10):6234-6239
The cDNA clones encoding the precursor form of glycinin A3B4 subunit have been identified from a library of soybean cotyledonary cDNA clones in the plasmid pBR322 by a combination of differential colony hybridizations, and then by immunoprecipitation of hybrid-selected translation product with A3-mono-specific antiserum. A recombinant plasmid, designated pGA3B41425, from one of six clones covering codons for the NH2-terminal region of the subunit was sequenced, and the amino acid sequence was inferred from the nucleotide sequence, which showed that the mRNA codes for a precursor protein of 516 amino acids. Analysis of this cDNA also showed that it contained 1786 nucleotides of mRNA sequence with a 5'-terminal nontranslated region of 46 nucleotides, a signal peptide region corresponding to 24 amino acids, an A3 acidic subunit region corresponding to 320 amino acids followed by a B4 basic subunit region corresponding to 172 amino acids, and a 3'-terminal nontranslated region of 192 nucleotides, which contained two characteristic AAUAAA sequences that ended 110 nucleotides and 26 nucleotides from a 3'-terminal poly(A) segment, respectively. Our results confirm that glycinin is synthesized as precursor polypeptides which undergo post-translational processing to form the nonrandom polypeptide pairs via disulfide bonds. The inferred amino acid sequence of the mature basic subunit, B4, was compared to that of the basic subunit of pea legumin, Leg Beta, which contained 185 amino acids. Using an alignment that permitted a maximum homology of amino acids, it was found that overall 42% of the amino acid positions are identical in both proteins. These results led us to conclude that both storage proteins have a common ancestor. 相似文献
28.
Purification and physicochemical characterization of murine T cell replacing factor (TRF) 总被引:9,自引:0,他引:9
K Takatsu N Harada Y Hara Y Takahama G Yamada K Dobashi T Hamaoka 《Journal of immunology (Baltimore, Md. : 1950)》1985,134(1):382-389
Murine T cell replacing factor (TRF) was purified from a cellfree supernatant of a T cell hybridoma (B151K12) that constitutively produces TRF. Two assay systems for TRF activity were employed: 1) induction of anti-DNP IgG PFC responses in cultures of splenic B cells from DNP-KLH-primed BALB/c mice, and 2) induction of IgM PFC in chronic B cell leukemic cells (BCL1). The purification scheme consisted of ammonium sulfate precipitation, DEAE-cellulose chromatography, Blue-Sepharose chromatography, hydroxylapatite chromatography, gel permeation with fast protein liquid chromatography (FPLC), and disc polyacrylamide gel electrophoresis. Overall, TRF was purified approximately 34,000-fold with a maximum 3.8% recovery of activity, and the specific activity of the purified TRF was approximately 9.6 X 10(4) U/mg. The TRF that is active in these systems is distinct from the other lymphokines such as IL 1, IL 2, BCGFI (now known as BSFp1), and gamma-interferon. The TRF is extremely hydrophobic, with an apparent m.w. of 50,000 to 60,000 on gel permeation chromatography and 18,000 on SDS-PAGE under reducing conditions. Highly purified B151-TRF abrogated the activity by treatment with trypsin but not with RNase. Moreover, it bound to lima bean agglutinin-Sepharose specific for N-acetylgalactosamine residues, indicating that B151-TRF is a glycosylated glycoprotein containing N-acetylgalactosamine residues. The role of N-acetylgalactosamine residues on TRF activity was additionally substantiated by the fact that the addition of appropriate amounts of N-acetylgalactosamine in the assay systems for TRF preferentially induced a profound suppression for TRF-mediated PFC responses. 相似文献
29.
Bovine erythrocyte sialoglycoprotein (GP-2) (1) containing lactoseries oligosaccharide chains, which showed highly specific inhibition of hemagglutination by HVJ (Hemagglutinating virus of Japan, Sendai virus), was incorporated into neuraminidase-treated chicken erythrocytes which had lost their biological responsiveness to the virus. The GP-2-incorporated erythrocytes were agglutinated and lyzed again by the virus. Incorporation of 1,900 molecules of GP-2 per asialoerythrocyte restored fairly well the susceptibility of the cells to HVJ-mediated agglutination and hemolysis. Treatment of the erythrocytes with neuraminidase again resulted in the complete abolishment of the response to HVJ. The above observations are consistent with the view that exogenous sialoglycoprotein, GP-2, can be functionally integrated into the surface membrane of asialoerythrocytes and serve as the receptor for HVJ during the initial adsorption-fusion phase of the virus infection of the target cells. 相似文献
30.
Coordinate repression of arginine aminopeptidase and three enzymes of the arginine deiminase pathway in Streptococcus mitis 总被引:2,自引:0,他引:2
Streptococcus mitis contains two arginine aminopeptidases (I and II) as an arginine-supplying system and the arginine deiminase pathway as an arginine-utilizing system. The levels of arginine aminopeptidase I and three enzymes of the arginine deiminase pathway were suppressed by glucose in an apparently coordinate manner. Enzyme II appeared to be constitutive. 相似文献