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1.
Aleuria aurantia lectin (AAL) shows sugar-binding specificity for L-fucose. A λgt11 expression library was constructed from A. aurantia poly(A) RNA and screened with a polyclonal antiserum directed against AAL. An immunopositive clone carrying 1.3-kb EcoRI fragment was obtained. The fragment encoded AAL, but lacked a nucleotide sequence corresponding to the two amino-terminal amino acids. The 5′-terminal part of the fragment was replaced with a chemically synthesized DNA fragment and inserted into an expression vector to yield a plasmid pKA-1. Escherichia coli carrying pKA-1 expressed functional AAL and the recombinant AAL showed the same immunological properties as those of natural AAL.  相似文献   
2.
Achondroplasia is the most common genetic form of human dwarfism, for which there is presently no effective therapy. C-type natriuretic peptide (CNP) is a newly identified molecule that regulates endochondral bone growth through GC-B, a subtype of particulate guanylyl cyclase. Here we show that targeted overexpression of CNP in chondrocytes counteracts dwarfism in a mouse model of achondroplasia with activated fibroblast growth factor receptor 3 (FGFR-3) in the cartilage. CNP prevented the shortening of achondroplastic bones by correcting the decreased extracellular matrix synthesis in the growth plate through inhibition of the MAPK pathway of FGF signaling. CNP had no effect on the STAT-1 pathway of FGF signaling that mediates the decreased proliferation and the delayed differentiation of achondroplastic chondrocytes. These results demonstrate that activation of the CNP-GC-B system in endochondral bone formation constitutes a new therapeutic strategy for human achondroplasia.  相似文献   
3.
The complete nucleotide sequence of a novel enteric virus, Aichi virus, associated with nonbacterial acute gastroenteritis in humans was determined. The Aichi virus genome proved to be a single-stranded positive-sense RNA molecule with 8,251 bases excluding a poly(A) tail; it contains a large open reading frame with 7,302 nucleotides that encodes a potential polyprotein precursor of 2,433 amino acids. The genome contains a 5′ nontranslated region (NTR) with 712 bases and a 3′ NTR with 240 bases followed by a poly(A) tail. The structure of the genome, VPg–5′ NTR–leader protein–structural proteins–nonstructural proteins–3′ NTR–poly(A), was found to be typical of a picornavirus. The VP0-VP3 and VP3-VP1 cleavage sites were determined to be Q-H and Q-T, respectively, by N-terminal amino acid sequence analyses using purified virion proteins. Possible cleavage sites, Q-G, Q-A, and Q-S, which cleave P2 and P3 polyproteins were found to be similar to those of picornaviruses. A dendrogram based on 3Dpol proteins indicated that Aichi virus is genetically distinct from the known six genera of picornaviruses including entero-, rhino-, cardio-, aphtho-, and hepatovirus and echovirus 22. Considering this together with other properties of the virus (T. Yamashita, S. Kobayashi, K. Sakae, S. Nakata, S. Chiba, Y. Ishihara, and S. Isomura, J. Infect. Dis. 164:954–957, 1991), we propose that Aichi virus be regarded as a new genus of the family Picornaviridae.  相似文献   
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Mutagenicities of quinoline and its derivatives.   总被引:11,自引:0,他引:11  
Quinoline, recently reported to be carcinogenic in rats [12], was mutagenic to Salmonella typhimurium tester strains TA100 and TA98 in the presence of the metabolic activation system S-9 mix. 2-Chloroquinoline, a non-carcinogen [12], was non-mutagenic with or without S-9 mix. 8-Hydroxyquinoline, which is t known to be carcinogenic, was mutagenic with S-9 mix to both bacterial strains. The mutagenicities of 17 other quinoline derivatives that are not known to be carcinogenic were tested, and 12 of these compounds were mutagenic.  相似文献   
6.
The accumulation of alpha1,2fucosylated antigens, such as Y (Fucalpha1,2Galbeta1,4 [Fucalpha1,3]GlcNAcbeta), Le(b) (Fucalpha1,2Galbeta1,3-[Fucalpha1,4]GlcNAcbeta), and H type 2 (Fucalpha1,2 Galbeta1,4GlcNAcbeta) occurs specifically within human colorectal tumor tissues and can be detected by an antifucosylated antigen antibody, such as the YB-2 antibody. In the present investigation, we found that the expression of these antigens bearing an alpha1,2-linked fucose correlated with the resistance of the tumor cells to anticancer treatments. Addition of an exogenous sugar acceptor for alpha1,2fucosyltransferase to the cell medium resulted in suppression of alpha1,2fucosylated antigen expression on the tumor cells and increased susceptibility to anticancer treatment. The increased susceptibility may be attributed to cancer cell-mediated priming by sugar acceptors for alpha1,2fucosyltransferase added to the medium.  相似文献   
7.
Molecular Biology Reports - Pyridoxine (PN), one of the vitamers of vitamin B6, plays an important role in the maintenance of epidermal function and is used to treat acne and rough skin. Clinical...  相似文献   
8.
Background aimsAdoptive immunotherapy is emerging as a potent anti-tumor treatment modality; Vγ9Vδ2 T cells may represent appropriate agents for such cancer immunotherapy. To improve the currently limited success of Vγ9Vδ2 T-cell–based immunotherapy, we examined the in vivo dynamics of these adoptively-transferred cells and hypothesized that interleukin (IL)-15 is the potential factor for Vγ9δ2 T cell in vivo survival.MethodsWe conducted a clinical trial of adoptive Vγ9Vδ2 T-cell transfer therapy in six colorectal cancer patients who received pulmonary metastasectomy. Patients' peripheral blood mononuclear cells were stimulated with zoledronate (5 μmol/L) and IL-2 (1000 IU/mL) for 14 d. Harvested cells, mostly Vγ9Vδ2 T cells, were given intravenously weekly without additional IL-2 eight times in total. The frequency, phenotype and common γ-chain cytokine receptor expression of Vγ9Vδ2 T cells in peripheral blood was monitored by flow cytometry at each time point during treatment and 4 and 12 weeks after the last administration.ResultsAdoptively transferred Vγ9Vδ2 T cells expanded well without exogenous IL-2 administration or lymphodepleting preconditioning. They maintained effector functions in terms of interferon-γ secretion and prompt release of cytotoxic granules in response to PMA/ionomycin or isopentenyl pyrophosphate–positive cells. Because they are IL-2Rα?IL-7Rα?IL-15Rα?IL-2Rβ+γc+, it is likely that IL-2 or IL-15 is required for their maintenance.ConclusionsThe persistence of large numbers of functionally active adoptively transferred Vγ9Vδ2 T cells in the absence of exogenous IL-2 implies that an endogenous factor, such as IL-15 transpresentation, is adequate to support these cells in vivo.  相似文献   
9.
The polymorphisms in the human leukocyte antigen (HLA) region are powerful tool for studying human evolutionary processes. We investigated genetic structure of Japanese by using five-locus HLA genotypes (HLA-A, -B, -C, -DRB1, and -DPB1) of 2,005 individuals from 10 regions of Japan. We found a significant level of population substructure in Japanese; particularly the differentiation between Okinawa Island and mainland Japanese. By using a plot of the principal component scores, we identified ancestry informative alleles associated with the underlying population substructure. We examined extent of linkage disequilibrium (LD) between pairs of HLA alleles on the haplotypes that were differentiated among regions. The LDs were strong and weak for pairs of HLA alleles characterized by low and high frequencies in Okinawa Island, respectively. The five-locus haplotypes whose alleles exhibit strong LD were unique to Japanese and South Korean, suggesting that these haplotypes had been recently derived from the Korean Peninsula. The alleles characterized by high frequency in Japanese compared to South Korean formed segmented three-locus haplotype that was commonly found in Aleuts, Eskimos, and North- and Meso-Americans but not observed in Korean and Chinese. The serologically equivalent haplotype was found in Orchid Island in Taiwan, Mongol, Siberia, and Arctic regions. It suggests that early Japanese who existed prior to the migration wave from the Korean Peninsula shared ancestry with northern Asian who moved to the New World via the Bering Strait land bridge. These results may support the admixture model for peopling of Japanese Archipelago.  相似文献   
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