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1.
In this study, we first established several CTL clones of (BALB/c x C57BL/6)F1 origin that were specific for either syngeneic UV female 1 or UV male 1 fibrosarcoma cell lines. All the CTL clones had Thy-1+ Lyt-2+ L3T4- phenotypes and showed Kd restriction when lysing the corresponding target cells. Sera obtained from syngeneic animals immunized with three CTL clones, 10B-5 for UV female 1, and CTL9 and CTL10 for UV male 1, showed specific inhibition of target cell lysis with the corresponding CTL clones. The inhibitory activities were found in sera of the majority of immunized animals. Because the inhibitory activity resides in protein A-binding fraction, mAb were produced by hybridizing spleen cells of hyperimmune animals. N1-56 was thus obtained from a mouse immunized with 10B-5 CTL clone reactive with UV female 1. N1-56 was clonotype specific, reacting with 10B-5 but not with other CTL lines or leukemia cell lines. No N1-56+ cells were detectable in thymocytes, lymph node cells, or spleen cells of either naive or UV female 1-immune CB6F1 mice. Immunoprecipitation showed that N1-56 reacts with 90,000 Mr molecules on 10B-5 CTL clone under nonreducing conditions and 45,000 Mr molecules under reducing conditions, indicating its reactivities with idiotypic determinants of TCR on the CTL clone. N1-56 inhibited lytic activity of 10B-5, but neither N1-56 nor alpha-10B-5 hyperimmune serum inhibited that of alpha-UV female 1 mixed lymphocyte tumor cell culture cells. N1-56 induced proliferation of 10B-5 without addition of Ag.  相似文献   
2.
The gene for steroid 18-hydroxylase (P-450C18) has been recently assigned to encode corticosterone methyl oxidases Type I and Type II which were previously postulated to catalyze the final two steps in the biosynthesis of aldosterone in humans. Molecular genetic analysis of the P-450C18 gene is three patients from three different families affected with CMO II deficiency has indicated that a point mutation of CGG----TGG (181Arg----Trp) in exon 3 and one of GTG----GCG (386Val----Ala) in exon 7 occur exclusively in the gene of the patients. Analysis of PCR products by restriction enzymes (HapII and HphI) has indicated that the patients are homozygous and the unaffected parent is heterozygous for both mutations, in accordance with the established concept that CMO II deficiency is inherited in an autosomal recessive manner. These data clearly provide the molecular genetic basis for the characteristic biochemical phenotype of CMO II clinical variants.  相似文献   
3.
The defective murine AIDS (MAIDS) virus has unique sequences in its p15gag and p12gag regions. To clarify whether these sequences are responsible for the development of MAIDS, we constructed recombinant viruses by replacing various regions of the gag gene of the nonpathogenic replication-competent LP-BM5 ecotropic virus with those of the MAIDS virus. Recombinants containing both unique sequences of the MAIDS virus were replication defective and induced MAIDS. However, a recombinant containing either the p15gag or p12gag region of the MAIDS virus was also replication defective but nonpathogenic in mice. A recombinant virus containing only the p30gag region of the MAIDS virus was replication competent and nonpathogenic. These results indicate that the p15gag and p12gag regions of the MAIDS virus do not function like those of replication-competent viruses and that both of the unique sequences in the p15gag and p12gag regions are required to develop MAIDS.  相似文献   
4.
The Duplan strain of murine leukemia virus induces murine AIDS in C57BL/6 mice. When spleen cells from C57BL/6 mice infected with the virus were transplanted into nude mice, subcutaneous solid tumors at the transplanted sites were formed and splenomegaly and lymphadenopathy were induced. These transplantable cells were Thy-1- CD4+ alpha-beta T-cell receptor-positive T cells and integrated with the pathogenic defective viral genome. These results indicate that neoplastic cells of T-cell lineage were induced by infecting C57BL/6 mice with murine AIDS virus.  相似文献   
5.
Isolation of a full-length cDNA encoding mouse aromatase P450   总被引:1,自引:0,他引:1  
A full-length cDNA clone for aromatase P450 has been isolated from a pregnant mouse ovarian cDNA library. The insert of this clone (2394 bp) contains a 1509-bp open reading frame encoding 503 amino acid residues together with a 46-bp 5'-untranslated stretch and an 839-bp 3'-untranslated region to which a poly(A) tract is attached. Northern blot analysis of ovarian RNA from pregnant mice reveals a major mRNA band of 2.5 kb with a minor band of 2.1 kb. Comparison of mouse aromatase P450 with that of rat, human, and chicken shows 91, 81, and 69% identity in the nucleotide sequence and 92, 79, and 69% identity in the deduced amino acid sequence, respectively. The membrane-spanning domain of mouse aromatase P450 is estimated to be an extremely hydrophobic segment located within the N-terminal region of the molecule. Furthermore, a highly conserved heme-binding domain is noticed.  相似文献   
6.
Using an EA rosetting system, it was observed that Fc receptors (FcR) were present on the surface of T cells as well as B cells, and that functional differences existed between FcR-positive (FcR+) and FcR-negative (FcR?) cells in both T and B cells in in vivo humoral immune responses. Approximately 15% of splenic T cells obtained by nylon wool passage are FcR+. The number of surface immunoglobulinbearing cells as detected by immunofluorescent staining accounted for less than 10% of these FcR+ cells. FcR+ and FcR? T+B-cell populations obtained from spleens contain 60 and 20% of surface immunoglobulin-positive cells, respectively. In the adoptive primary response in which horse RBC and dinitrophenyl-conjugated dextran (DNP-DE) were used as T-dependent and T-independent antigens, respectively, the majority of precursor B cells were FcR?. In the secondary response using hapten-primed B cells and carrier-primed T cells, the majority of memory B cells for a haptenic determinant were also FcR?. Furthermore, the majority of functional cells exerting helper activity in the same hapten-carrier system are FcR? cells, and FcR+ T cells collaborate much less effectively with either memory B cells or helper FcR? T cells.  相似文献   
7.
Abstract

Japan is an island nation which is heavily dependent upon the surrounding seas for food, importation of raw materials, exportation of finished products, and for national security. Japan is also the world's largest fishing and shipping nation, which poses certain problems and imposes special responsibilities on her. Japan has traditionally followed the principle of freedom of the high seas, but under the external pressure of developments at UNCLOS III and unilateral actions by other states, Japan has been forced to accept and accommodate herself to the new concept of transit passage through international straits, the twelve nautical mile territorial sea, and the two hundred nautical mile exclusive economic zone, which were perceived as contrary to her national interests. However, Japan is adapting to the new ocean regime that is emerging from both customary and conventional international law, because she has confidence that a stable regime is more important in the long run than some short‐term advantages that might be obtained through the absence of any regime. Furthermore, as one of the highly developed nations of the world, Japan feels a special responsibility to play an effective role in aiding and assisting the developing nations of the world.  相似文献   
8.
Highly pathogenic avian influenza viruses (HPAIVs) cause lethal infection in chickens. Severe cases of HPAIV infections have been also reported in mammals, including humans. In both mammals and birds, the relationship between host cytokine response to the infection with HPAIVs and lethal outcome has not been well understood. In the present study, the highly pathogenic avian influenza viruses A/turkey/Italy/4580/1999 (H7N1) (Ty/Italy) and A/chicken/Netherlands/2586/2003 (H7N7) (Ck/NL) and the low pathogenic avian influenza virus (LPAIV) A/chicken/Ibaraki/1/2005 (H5N2) (Ck/Ibaraki) were intranasally inoculated into chickens. Ty/Italy replicated more extensively than Ck/NL in systemic tissues of the chickens, especially in the brain, and induced excessive mRNA expression of inflammatory and antiviral cytokines (IFN-γ, IL-1β, IL-6, and IFN-α) in proportion to its proliferation. Using in situ hybridization, IL-6 mRNA was detected mainly in microglial nodules in the brain of the chickens infected with Ty/Italy. Capillary leakage assessed by Evans blue staining was observed in multiple organs, especially in the brains of the chickens infected with Ty/Italy, and was not observed in those infected with Ck/NL. In contrast, LPAIV caused only local infection in the chickens, with neither apparent cytokine expression nor capillary leakage in any tissue of the chickens. The present results indicate that an excessive cytokine response is induced by rapid and extensive proliferation of HPAIV and causes fatal multiple organ failure in chickens.  相似文献   
9.
10.
Lipase-catalyzed kinetic resolution of the N,N-dialkyl-3-benzyloxymethyl-4-hydroxybutanamide 10a,b afforded the acetate 11a,b with (R) configuration, whereas the N-monoalkyl-3-benzyloxymethyl-4-hydroxybutanamide 10c-e gave the acetate 11c-e with (S) configuration. The butanamide 10 smoothly cyclized to give chiral 4-benzyloxymethyldihydrofuran-2-one 9 without racemization, which was effectively transformed into highly stereocontrolled virginiae butanolide C (VB C).  相似文献   
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