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81.
Abstract In this paper, the genus Zrepacma is reported for the first time from China; three new species from Shaanxi Province are described: Irepacm grandis sp. nov., Irepacma furuimacularis sp. nov. and Irepacma pallidia sp. nov., The genitalia of both sexes are illustrated. 相似文献
82.
Ichikawa K Liu W Fleck M Zhang H Zhao L Ohtsuka T Wang Z Liu D Mountz JD Ohtsuki M Koopman WJ Kimberly R Zhou T 《Journal of immunology (Baltimore, Md. : 1950)》2003,171(2):1061-1069
TRAIL has been proposed as an anti-inflammatory cytokine in animal models of rheumatoid arthritis (RA). Using two agonistic mAbs specific for TRAIL-R1 (DR4) and TRAIL-R2 (DR5), we examined the expression and function of these death receptors in RA synovial fibroblast cells. The synovial tissues and primary synovial fibroblast cells isolated from patients with RA, but not those isolated from patients with osteoarthritis, selectively expressed high levels of cell surface DR5 and were highly susceptible to anti-DR5 Ab (TRA-8)-mediated apoptosis. In contrast, RA synoviocytes did not show increased expression of TRAIL-R1 (DR4), nor was there any difference in expression of Fas between RA and osteoarthritis synovial cells. In vitro TRA-8 induced apoptosis of RA synovial cells and inhibited production of matrix metalloproteinases induced by pro-inflammatory cytokines. In vivo TRA-8 effectively inhibited hypercellularity of a SV40-transformed RA synovial cell line and completely prevented bone erosion and cartilage destruction induced by these cells. These results indicate that increased DR5 expression and susceptibility to DR5-mediated apoptosis are characteristic of the proliferating synovial cells in RA. As highly proliferative transformed-appearing RA synovial cells play a crucial role in bone erosion and cartilage destruction in RA, the specific targeting of DR5 on RA synovial cells with an agonistic anti-DR5 Ab may be a potential therapy for RA. 相似文献
83.
Recovery of transgenic rice plants expressing the rice dwarf virus outer coat protein gene (S8) 总被引:3,自引:0,他引:3
H. H. Zheng Y. Li Z. H. Yu W. Li M. Y. Chen X. T. Ming R. Casper Z. L. Chen 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1997,94(3-4):522-527
The coding region of the eighth largest segment (S8) of the rice dwarf virus (RDV) was obtained from a RDV Fujian isolate.
It was then cloned into pTrcHisA for expression in E. coli and into vector pE3 for plant transformation. By using callus derived from mature rice embryos as the target tissue, we obtained
regenerated rice plants after bombardment of the former with plasmid pE3R8 containing the RDV S8 gene and the marker gene
neomycin phosphotransferase (NPT II). Southern blotting confirmed the integration of the RDV S8 gene into the rice genome.
The expression of the outer coat protein in both E. coli and rice plants was confirmed by western blotting. The recovery of transgenic rice plants expressing S8 gene is an important
step towards studying the function of the RDV genes and obtaining RDV-resistant rice plants.
Received: 1 March 1996 / Accepted: 2 August 1996 相似文献
84.
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86.
Dong Zheng Qiang Sun Zhaoliang Su Fanzhi Kong Xiaoju Shi Jia Tong Pei Shen Tianqing Peng Shengjun Wang Huaxi Xu 《PloS one》2013,8(4)
The outer membrane protein RagB is one of the major virulence factors of the periodontal pathogen Porphyromonas gingivalis (P. gingivalis). In order to induce protective immune response against P. gingivalis infection, an mGITRL gene-linked ragB DNA vaccine (pIRES-ragB-mGITRL ) was constructed. Six-week-old female BALB/c mice were immunized with pIRES-ragB-mGITRL through intramuscular injection and then challenged by subcutaneous injection in the abdomen with P. gingivalis. RagB-specific antibody-forming cells were evaluated by an Enzyme-linked immunosorbent spot, and specific antibody was determined by enzyme-linked immunosorbent assay. In addition, the frequencies of Tfh and IFN-γ+ T cells in spleen were measured using flow cytometer, and the levels of IL-21 and IFN-γ mRNA or proteins were detected by real time RT-PCR or ELISA. The data showed that the mGITRL-linked ragB DNA vaccine induced higher levels of RagB-specific IgG in serum and RagB-specific antibody-forming cells in spleen. The frequencies of Tfh and IFN-γ+ T cells were obviously expanded in mice immunized by pIRES-ragB-mGITRL compared with other groups (pIRES or pIRES-ragB ). The levels of Tfh and IFN-γ+ T cells associated cytokines were also significantly increased in pIRES-ragB-mGITRL group. Therefore, the mice immunized with ragB plus mGITRL showed the stronger resistant to P. gingivalis infection and a significant reduction of the lesion size caused by P. gingivalis infection comparing with other groups. Taken together, our findings demonstrated that intramuscular injection of DNA vaccine ragB together with mGITRL induced protective immune response dramatically by increasing Tfh and IFN-γ+ T cells and antibody production to P. gingivalis. 相似文献
87.
Qiupeng Zheng Jing Du Zhaofeng Zhang Jianhua Xu Lingyuan Fu Yunlei Cao Xianliang Huang Lingli Guo 《Gene》2013
Vascular malformations (VMs) are common congenital and neonatal dysmorphogenesis. VMs mostly occur sporadically with a few exceptions of inheritability. Tie2/angiopoietins-2 (Ang-2) and VEGF/KDR pathways are known to be involved in normal and pathogenic angiogenesis. Our study was aimed to test the contribution of these pathway gene variants to VMs. A total of 8 variants were found among 103 VM patients and 142 healthy controls. These variants comprised rs638203, rs639225, rs80338908 and rs80338909 in Tie2 gene, rs1870377 and rs2305949 in KDR gene, rs79337921 and rs34590960 in ANTXR1 gene. Our results indicated that rs638203 (p = 0.029) and rs639225 (p = 0.018) in Tie2 gene were associated with VM. A further bioinformatics analysis suggested the rs638203-G and rs639225-G might cause an abnormal splicing of Tie2 gene into to a defective protein. Our results identified two novel Tie2 gene polymorphisms with genetic susceptibility to VMs, although future functional validation of the two polymorphisms is warranted in the future. 相似文献
88.
Neurochemical Research - Evidence exists reporting that miR-410 may rescue neurological deficits, neuronal injury, and neuronal apoptosis after experimental hypoxic ischemia. This study aimed to... 相似文献
89.
Chiyu Li Jia Chen Xiaoyan Li Xin Zhang Ying Liu Sirui Zhu Long Wang Heping Zheng Sheng Luan Jiada Li Feng Yu 《植物学报(英文版)》2022,64(10):1901-1915
Plant shoot phototropism is triggered by the formation of a light-driven auxin gradient leading to bending growth. The blue light receptor phototropin 1(phot1) senses light direction, but how this leads to auxin gradient formation and growth regulation remains poorly understood. Previous studies have suggested phot1’s role for regulated apoplastic acidification, but its relation to phototropin and hypocotyl phototropism is unclear. Herein, we show that blue light can cause phot1 to interact with... 相似文献
90.
Host-mediated modification of Sau3AI restriction in Listeria monocytogenes: prevalence in epidemic-associated strains. 下载免费PDF全文
Most major food-related outbreaks of listeriosis have been traced to a cluster of genetically related strains of serovar 4b (epidemic clone). In spite of numerous searches, distinct bacteriologic or virulence-related features unique to these strains have eluded identification, although a restriction fragment length polymorphism (RFLP) characteristic of the epidemic clone has previously been described (W. Zheng and S. Kathariou, Appl. Environ. Microbiol. 61:4310-4314, 1995). We found that DNAs from 75 strains which were derived from three separate outbreaks and which had the epidemic clone-specific RFLP were also invariably resistant to digestion by Sau3AI and other restriction endonucleases sensitive to cytosine methylation at 5' GATC 3' sites. This modification of Sau3AI restriction was host mediated, as it did not persist when DNA was cloned and propagated in Escherichia coli, and was uncommon among other Listeria strains. Epidemic-associated strains with this modification were resistant to infection by phage propagated in a serotype 4b strain which was not known to be involved in an epidemic and which lacked the epidemic clone-specific RFLP. Screening for susceptibility to MboI digestion revealed that these epidemic strains lacked methylation of adenines at GATC sites. This type of modification was rare among Listeria strains and was found in only three (of eight screened) strains of serovar 1/2b, possibly representing one clonal lineage. 相似文献