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1.
Toshiyuki Hamaoka Yasuyuki Takai Atsushi Kosugi Yumiko Mizushima Junko Shima Tsuneo Kusama Hiromi Fujiwara 《Cancer immunology, immunotherapy : CII》1985,20(3):183-188
Summary A new haptenic compound, a muramyl dipeptide (MDP) derivative (designated as L4-MDP-ONB) cross-reactive with Bacillus Calmette Guerin (BCG) was synthesized. The cross-reactivity of L4-MDP hapten to BCG was demonstrated from the following evidence; (a) lymph node cells from BCG-primed C3H/HeN mice exhibited appreciable L4-MDP-specific proliferative responses to the in vitro stimulation of L4-MDP-modified syngeneic cells (L4-MDP-self); (b) inoculation of L4-MDP-self into footpads of BCG-primed C3H/HeN mice elicited ample delayed type-hypersensitivity (DTH) responses in vivo as measured by footpad swelling; and (c) BCG-primed mice contained L4-MDP-reactive helper T cell activity which functions to augment the generation of effector T cell responses to cell surface antigens. This crossreactivity between L4-MDP hapten and BCG as measured by the helper T cell activity was applied to enhanced induction of tumor-specific immunity. When BCG-primed C3H/HeN mice were immunized with L4-MDP-modified syngeneic X5563 tumor cells, these mice could generate augmented tumor-specific in vivo protective (tumor neutralizing) immunity as well as in vitro cytotoxic T cell responses. These results indicate the effectiveness of L4-MDP hapten in augmenting tumor-specific immunity. The present approach is discussed in the context of potential advantages of this new hapten for its future application to clinical tumor systems. 相似文献
2.
Uncoupling of Rat Cerebral Cortical α2 -Adrenoceptors from GTP-Binding Proteins by N-Ethylmaleimide 总被引:2,自引:0,他引:2
Pretreatment of membranes from rat cerebral cortex with N-ethylmaleimide (NEM) decreased [3H]-clonidine binding in a concentration-dependent manner. The Bmax values of high-affinity sites for [3H]clonidine were reduced by 50 microM NEM treatment. Treatment with 500 microM NEM diminished the sum of Bmax of both high- and low-affinity components. GTP, Na+, and Mn2+ exerted little effect on [3H]clonidine binding in NEM-treated membranes. The addition of purified GTP-binding proteins caused an increase in the binding to the membranes pretreated with 50 microM NEM, but did not increase [3H]-clonidine binding in membranes treated with 500 microM NEM. In contrast, NEM pretreatment inhibited islet activating protein (IAP)-catalyzed ADP ribosylation of membrane-bound (41,000-dalton) and purified (39,000/41,000-dalton) GTP-binding proteins. From these results, it is suggested that two or three categories of essential sulfhydryl groups are involved in the coupling between agonist, alpha 2-adrenoceptor, and GTP-binding protein. One is a highly sensitive site to NEM (a concentration range of 1-50 microM), which is probably a cysteine residue, IAP-catalyzed ADP-ribosylating site on the alpha-subunit of GTP-binding protein. Other sites have low sensitivity to NEM (a concentration range of 0.1-1 mM), and are the binding domain of agonist and/or the coupling domain of GTP-binding protein on the alpha 2-adrenoceptor. In addition, Ki-ras p21 protein may lack the capacity to couple with the alpha 2-adrenoceptor. 相似文献
3.
Complementation study of peroxisome-deficient disorders by immunofluorescence staining and characterization of fused cells 总被引:5,自引:0,他引:5
Shigehiro Yajima Yasuyuki Suzuki Nobuyuki Shimozawa Seiji Yamaguchi Tadao Orii Yukio Fujiki Takashi Osumi Takashi Hashimoto Hugo W. Moser 《Human genetics》1992,88(5):491-499
Summary Genetic heterogeneity in peroxisome-deficient disorders, including Zellweger's cerebrohepatorenal syndrome, neonatal adrenoleukodystrophy and infantile Refsum disease, was investigated. Fibroblasts from 17 patients were fused using polyethylene glycol, cultivated on cover slips, and the formation of peroxisomes in the fused cells was visualized by immunofluorescence staining, using anti-human catalase IgG. Two distinct staining patterns were observed: (1) peroxisomes appeared in the majority of multinucleated cells, and (2) practically no peroxisomes were identified. Single step 12-(1-pyrene) dodecanoic acid/ultraviolet (P12/UV)-selection confirmed that the former groups were resistant to this selection, most of the surviving cells contained abundant peroxisomes, and the latter cells died. In the complementary matching, [1-14C]lignoceric acid oxidation and the biosynthesis of peroxisomal proteins were also normalized. Five complementation groups were identified. Group A: Zellweger syndrome and infantile Refsum disease; Groups B, C and D: Zellweger syndrome; Group E: Zellweger syndrome, neonatal adrenoleukodystrophy and infantile Refsum disease. We compared these groupings with those of Roscher and identified eight complementation groups. There was no obvious relation between complementation groups and clinical phenotypes. These results indicate that the transport, intracellular processing and function of peroxisomal proteins were normalized in the complementary matching and that at least eight different genes are involved in the formation of normal peroxisomes and in the transport of peroxisomal enzymes. 相似文献
4.
Green Lavandula vera callus that produced biotin was preservedsuccessfully in liquid nitrogen for up to 3 weeks. We foundthat the callus recovered after the freeze-preservation, retainingnot only the biosynthetic capability for biotin but also differentiationpotentials such as chloroplast development and plantlet formation.The significance of retention of the metabolic and differentiationpotentials of the callus is discussed in terms of the freeze-preservationof plant genetic resources.
* This study is dedicated to the late Professor J. Ashida. (Received September 1, 1982; Accepted November 5, 1982) 相似文献
5.
The inhibition of forskolin-stimulated adenylate cyclase activity by 5-hydroxytryptamine (5-HT) receptor agonists was measured in rat hippocampal membranes isolated from animals treated with vehicle or islet-activating protein (IAP; pertussis toxin). In vehicle-treated animals, 5-HT, 8-hydroxy-2-(di-n-propylamino)tetralin, buspirone, and gepirone were potent in inhibiting forskolin-stimulated adenylate cyclase activity with EC50 values of 60, 76, 376, and 530 nM, respectively. IAP treatment reduced by 30-55% the 5-HT1A agonist inhibition of adenylate cyclase activity via 5-HT1A receptors. The data indicate that the inhibitory guanine nucleotide-binding protein or Go (a similar GTP-binding protein of unknown function purified from brain) mediates the 5-HT1A agonist inhibition of hippocampal adenylate cyclase. 相似文献
6.
Fatal attack on an infant by an adult female tonkean macaque 总被引:1,自引:0,他引:1
We describe a fatal attack on a 10-month-old female infant by an adult female Tonkean macaque (Macaca tonkeana)in a semi-free-ranging group. During an intense conflict involving many group members, an adult female, the second most dominant
in the group, attacked the infant of a lower-ranking female. The attacker remained near the victim for approximately 20 min,
grabbing and biting it repeatedly, until the mother retrieved the infant. She died 2 days later. An autopsy revealed no lethal
injury;the main cause of death was starvation or dehydration or both. We discuss social conditions under which a fatal attack by
an adult female might occur. 相似文献
7.
Kazuhito Ohishi Yasuyuki Kurimoto Norimitsu Inoue Yuichi Endo Junji Takeda Taroh Kinoshita 《Genomics》1996,34(3):340
Many eukaryotic proteins are bound to the plasma membrane via a glycosylphosphatidylinositol (GPI) anchor. Its core backbone, which is conserved in different organisms, is synthesized in the endoplasmic reticulum by the sequential addition of glycan components to phosphatidylinositol. One of the human GPI synthesis genes,PIGF(phosphatidylinositol glycan complementation class F), which is involved late in the synthesis pathway, has been cloned. In this study, we isolated complementary and genomic clones ofPigf,a murine counterpart ofPIGF. Pigfencodes a 219 amino acid protein that complements a class F mutation. ThePigfgene consists of six exons spanning 30 kb and was mapped to chromosome 17 at 17E4–E5. These features are very similar toPIGF,thus demonstrating the interspecies conservation of structure, function, gene organization, and genetic locus between these GPI synthesis genes. The results also extend a region in murine distal chromosome 17 that is syntenic to human chromosome 2p16–p22. 相似文献
8.
Peracetylated samples of cyclomaltoheptaose (β-cyclodextrin, β-CD) and its methylated derivative were studied by 13C NMR. The acetyl carbonyl carbon signal in peracetylated β-CD was resolved into a triplet, and the three peaks were assigned by long-range C---H COSY and INAPT techniques. The individual carbonyl peak was found to be indicative of the location of the acetyl group on the 2, 3, and 6 position in the glucose residues. An acetylated derivative of a partly methylated β-CD was also subjected to 13C NMR analysis to determine the distribution of acetyl and, subsequently, methyl groups on the glucose residues. 相似文献
9.
ADP-Ribosylation of Histones in Nuclei Isolated from Embryos of the Sea Urchin, Hemicentrotus pulcherrimus 总被引:1,自引:1,他引:0
Shigehisa Furuya Yasuyuki Kamata Ikuo Yasumasu 《Development, growth & differentiation》1994,36(1):103-110
Two-dimensional electrophoresis (2D-PAGE) of a histone fraction isolated from nuclei of embryos of the sea urchin Hemicentrotus pulcherrimus exhibited almost all histone species at all stages examined. At the gastrula stage, a spot of H1A became evident and three spots closely associated with one another were found in place of a single spot of H2A.1. In the histone fraction isolated from [adenylate-32 P] NAD+ -treated nuclei of all stages examined, autoradiograms of 2D-PAGE exhibited spots of mono [ADP-ribosyl] ated H1 and polymodified H2B.2, H3.1, H3.3 and H4 but did not show ADP-ribosylated H2A.1, H2A.2 or H2B.1. Poly [ADP-ribosyl] ated H3.2, found in morulae, was not detectable in blastulae and gastrulae. Treatment with dimethylsulfate, known to activate ADP-ribosylation in other cell types, induced poly [ADP-ribosyl] ation of H2A.2 and H2B.1 in embryos at all stages examined, and also polymodification of H3.2 in gastrulae. ADP-ribosylation of H1, H2B.2, H3.1 and H3.3 was hardly affected by dimethylsulfate treatment, though modification of H4 was blocked by this treatment. Probably, strong regulation of ADP-ribosyltransferase reactions causes failures of modification of H2A.2 and H2B.1 throughout early development and also of H3.2 at the gastrula stage. Regulation of histone ADP-ribosylation is thought to alter chromatin structures and the rate of gene expression, contributing to cell differentiation. 相似文献
10.
Kazuhiro Ichikawa Yasuyuki Sakai Akiyoshi Sakoda Motoyuki Suzuki 《Biotechnology Techniques》1994,8(6):385-388
Summary Primary culture of rat hepatocytes in hormone-free medium using membrane-supported collagen sandwich maintained their cellular morphology and expressed albumin secretion for about 3 weeks in vitro. It was reconfirmed that mimicking the cellular environment in vivo was effective for cellular maintenance. 相似文献