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11.
Qi-Wen Fan Kenji Kadomatsu Kenji Uchimura Takashi Muramatsu 《Development, growth & differentiation》1998,40(3):277-286
Embigin and basigin are highly glycosylated transmembrane glycoproteins with two immunoglobulin domains and form a subgroup in the immunoglobulin superfamily. Previous studies have demonstrated the functional significance of these molecules. In the present study, in situ hybridization analysis of their expression was performed during mouse embryogenesis. Embigin was strongly expressed in the endoderm during early postimplantation embryogenesis, and in the somite stage in the gut and visceral endoderm. Embryonic ectoderm and its derivative tissues weakly to moderately expressed this molecule. From day 10 to 15 of gestation, no embigin signal was detected. Basigin was more broadly expressed. During the organogenesis period, basigin was expressed in various epithelial tissues, brain ventricles, the spinal cord and dorsal root ganglion. The modes of expression of these two proteins throughout the egg cylinder stage correlated with the expression of the carbohydrate markers that they carry; embigin with Dolichos biflorus agglutinin binding sites and basigin with Lex antigen and more closely with fucosyltransferase IV, which forms the antigenic epitope. These findings imply that proteins with specific carbohydrate epitopes play roles in early postimplantation embryogenesis. 相似文献
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13.
Heparin-binding epidermal growth factor-like growth factor (HB-EGF) is a member of the epidermal growth factor family and has a variety of physiological and pathological functions. Modulation of HB-EGF activity might have a therapeutic potential in the oncology area. We explored the therapeutic possibilities by characterizing the in vitro biological activity of anti-HB-EGF monoclonal antibody Y-142. EGF receptor (EGFR) ligand and species specificities of Y-142 were tested. Neutralizing activities of Y-142 against HB-EGF were evaluated in EGFR and ERBB4 signaling. Biological activities of Y-142 were assessed in cancer cell proliferation and angiogenesis assays and compared with the anti-EGFR antibody cetuximab, the HB-EGF inhibitor CRM197, and the anti-vascular endothelial growth factor (VEGF) antibody bevacizumab. The binding epitope was determined with alanine scanning. Y-142 recognized HB-EGF as well as the EGFR ligand amphiregulin, and bound specifically to human HB-EGF, but not to rodent HB-EGF. In addition, Y-142 neutralized HB-EGF-induced phosphorylation of EGFR and ERBB4, and blocked their downstream ERK1/2 and AKT signaling. We also found that Y-142 inhibited HB-EGF-induced cancer cell proliferation, endothelial cell proliferation, tube formation, and VEGF production more effectively than cetuximab and CRM197 and that Y-142 was superior to bevacizumab in the inhibition of HB-EGF-induced tube formation. Six amino acids in the EGF-like domain were identified as the Y-142 binding epitope. Among the six amino acids, the combination of F115 and Y123 determined the amphiregulin cross-reactivity and that F115 accounted for the species selectivity. Furthermore, it was suggested that the potent neutralizing activity of Y-142 was derived from its recognition of R142 and Y123 and its high affinity to HB-EGF. Y-142 has a potent HB-EGF neutralizing activity that modulates multiple biological activities of HB-EGF including cancer cell proliferation and angiogenic activities. Y-142 may have a potential to be developed into a therapeutic agent for the treatment of HB-EGF-dependent cancers. 相似文献
14.
A Taku R D Garman M A Wabuke-Bunoti J M Curtsinger C Haarstad D P Fan V L Braciale T J Braciale 《Journal of immunology (Baltimore, Md. : 1950)》1984,133(1):502-508
A helper factor termed cytolytic T lymphocyte helper factor (CHF) that is needed for the generation of allospecific mouse cytolytic T lymphocytes (CTL) in vitro was produced by mouse spleen cells 3 to 4 days after the time when interleukin 2 (IL 2) had reached its maximal production. These kinetics were observed by stimulation of immune spleen cells with allogeneic tumor or spleen cells, with Sendai or influenza viral peptides, with virus infected cells, or with concanavalin A (Con A). CHF produced by rat spleen cells was able to help in the generation of mouse CTL, indicating that this cytokine was not restricted genetically. CHF could also be made by WEHI-3 and EL4 cell lines, as well as cloned cytolytic and helper T cells. The production of CHF by WEHI-3 cells argues that CHF is not IL 2. In addition, if CHF was not present early in the in vitro stimulation no CTL were generated, suggesting that CHF participated in the activation of CTL precursors. The addition of IL 2-containing conditioned medium to the CHF assay resulted in no substantial CTL generation, although significant cellular proliferation was observed. In contrast, CHF-containing conditioned medium allowed the generation of CTL in the absence of the same level of proliferation. 相似文献
15.
101 species of oribatid mites and 12 species of helminths--anoplocephalids, transmitted by these mites, were found out by Soviet-Vietnam studies in agroecosystems and tropical forests of northern and southern Vietnam. Helminths were recorded from graminivorous mammals as follows: horses, zebu, sheep, goats, buffaloes, deer, hares, elephant, 2 species of rates, 5 species of monkeys and 11 species of birds. 相似文献
16.
溶瘤病毒(oncolytic virus,OVs)疗法是治疗肿瘤的一种新方法,它可通过直接杀死肿瘤细胞并引起机体的免疫反应发挥作用.然而天然溶瘤病毒有一定的局限性,因此需将各种不同的病毒作为载体,通过基因修饰的方法增强或减弱病毒毒力并导入新的功能性基因,以提高其溶瘤作用.目前可以作为溶瘤病毒载体的有单纯疱疹病毒、腺病毒、牛痘病毒、水泡性口炎病毒、麻疹病毒、腮腺炎病毒、脊髓灰质炎病毒等.这些病毒载体均可通过不同的基因修饰方法,靶向性感染并杀死不同的肿瘤细胞,获得较好的溶瘤作用.本文综述了几种溶瘤病毒载体的基因修饰方法,以及修饰后的溶瘤效果. 相似文献
17.
18.
Cahara Ghauri from China with three species is reviewed here. Two of them, Cahara incisura
sp. n. and Cahara nodula
sp. n. are described here. Key to the three Chinese species, habitus photographs and illustrations of genitalia are also provided. All examined materials including the types of three species mentioned are deposited in the Institute of Entomology, Nankai University, Tianjin, China (NKUM). 相似文献
19.
Xu Liu Ben Chen Lulan Chen Wan-Ting Ren Juan Liu Guoxiang Wang Wei Fan Xin Wang Yun Wang 《PloS one》2013,8(4)
Phenol red is widely used in cell culture as a pH indicator. Recently, it also has been reported to have estrogen-like bioactivity and be capable of promoting cell proliferation in different cell lines. However, the effect of phenol red on primary neuronal culture has never been investigated. By using patch clamp technique, we demonstrated that hippocampal pyramidal neurons cultured in neurobasal medium containing no phenol red had large depolarization-associated epileptiform bursting activities, which were rarely seen in neurons cultured in phenol red-containing medium. Further experiment data indicate that the suppressive effect of the phenol red on the abnormal epileptiform burst neuronal activities was U-shape dose related, with the most effective concentration at 28 µM. In addition, this concentration related inhibitory effect of phenol red on the epileptiform neuronal discharges was mimicked by 17-β-estradiol, an estrogen receptor agonist, and inhibited by ICI-182,780, an estrogen receptor antagonist. Our results suggest that estrogen receptor activation by phenol red in the culture medium prevents formation of abnormal, epileptiform burst activity. These studies highlight the importance of phenol red as estrogen receptor stimulator and cautions of careful use of phenol red in cell culture media. 相似文献
20.
Jing Hu Wail M. Hassan Guorong Chen Yanlin Li Wenqiao Fan Wei Wang 《Ecological Entomology》2019,44(6):800-809
1. The Qilian Mountains represent one of the key livestock‐raising grasslands in China. The two main herbivore species raised in this area – yaks and sheep – are of critical economical value. Grasshoppers compete with these animals for available nutrients, creating multifaceted relationships between livestock, grasshoppers and plants. A clear understanding of such relationships is lacking and is urgently needed to guide conservation efforts. 2. This study aims to document the effects of yak and sheep grazing on grasshopper assemblages and to elucidate the underlying mechanisms of such effects. 3. It is shown here that yaks and sheep impact grasshopper assemblages differently. Grasshopper assemblages exhibited lower density, biodiversity, richness, and evenness of distribution in yak‐grazed pastures than in grazing‐free grasslands. Sheep‐grazed pastures exhibited a dramatically divergent picture, with elevated density, biodiversity and richness, and a slightly decreased evenness of distribution. Grasshoppers were generally larger in grazed pastures than in grazing‐free grasslands, especially in yak‐grazed plots. 4. The present study suggests that differences between yak and sheep pastures in plant assemblage structure and plant traits are probably the underlying forces driving the differences in grasshopper assemblage structure and grasshopper traits, respectively. 5. The study shows that the grasshopper habitat indicator species differ between yak and sheep pastures, raising the possibility that such indicators can be used to monitor grassland usage and degradation in the Qilian Mountains. 6. These results provide novel insights into the dynamic interactions of common domesticated herbivore species, grasshoppers and plants in Qilian Mountains, which augment current knowledge and may ultimately lead to better conservation practices. 相似文献