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991.
WU Xiao-bin PENG Jun-sheng LI Chu-jun WANG Hui DU Yan-ping YANG Zu-li XIANG Jun HU Kun-hua LIU Wei LI Ming-tao 《园艺学报》2009,25(6):1098-1103
AIM: To investigate the associated proteins and sensitive biomarkers for early diagnosis of colorectal adenocarcinoma by comparing the results of differential proteomic analysis between colorectal adenoma and early malignantly transformed adenoma. METHODS: Two-dimensional gel electrophoresis was used to define patterns of protein expressions of colorectal adenoma and early malignantly transformed adenoma. Proteins expressed differentially among groups were detected, cut out and analyzed by MALDI-TOF/TOF mass spectrometry. RESULTS: Two-dimensional protein maps of colorectal adenoma and early malignantly transformed adenoma were analyzed with gel-analysis software, an average of 1 672 spots in adenoma, 1 732 in early malignantly transformed adenoma were observed. 28 spots of a 1.5-fold change were found, including 15 proteins down-regulated and 13 up-regulated in early malignantly transformed adenoma, in which 23 proteins were identified by mass spectrometry, the rate of identification was 82.14%. 13 differential proteins were attained, 8 were up-regulated and 5 were down-regulated, which was classified to 6 categories, including protease inhibitor, complement, immunoglobulin, keratoproteins, signal transduction protein and function-unknown proteins. CONCLUSION: The changes of serum proteins in early malignantly transformed adenoma from adenoma can be identified by proteomic technology. Proteins detected in the study may provide new biomarkers correlated with biological behavior of colorectal adenocarcinoma. 相似文献
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Purple flowering stalk (Brassica campestris ssp. chinensis var.purpurea Hort.) was generally regarded as a recalcitrant species for microspore culture in Brassica crops. Conditions for reliable induction of microspore embryogenesis were studied in 12 genotypes of purple flowering stalk. A treatment of short heat shock to microspore by incubating at 32 °C for 18 h was suitable for the survival of microspores, sustained cell divisions, and further induced embryogenesis. Subsequently, the reduced concentration of macro salts (1/2 NLN) provided an optimal condition for the development of embryoids. Under the optimized conditions for microspore embryoid development, 10 genotypes responded to microspore culture with the frequencies ranging from 2.7 to 70.5 embryoids per dish. However, regenerated plants were obtained from 9 genotypes, and more than 75% these regenerated plants were double haploid. This report establishes an efficient protocol for microspore culture and offers great potential for DH breeding in purple flowering stalk. 相似文献
994.
L.H. Wang X.H. Gu M.Y. Hua S.L. Mao Z.H. Zhang D.L. Peng X.F. Yun B.X. Zhang 《Scientia Horticulturae》2009
The root-knot nematodes (Meloidogyne spp.) are important nematode pests and cause serious diseases in pepper in the world. No molecular markers linked to the nematodes resistance N gene have been reported. In this paper, ‘Carolina Wonder’ (Capsicum annuum L.), a sweet pepper line resistant to root-knot nematode with N gene, ‘20080-5-29’ (C. annuum L.), an inbred line susceptible to root-knot nematode with good horticultural characteristics, and their F2 progeny with 320 individuals were used as materials. Evaluation of resistance and susceptibility of parental lines, F1 and F2 progeny inoculated with root-knot nematodes (Meloidogyne incognita) were carried out. ‘Bulked segregant analysis’ method was used to search for polymorphic markers from 512 pairs of AFLP primers. Based on the assessment of resistance and susceptibility and polymorphism of the AFLP marker in F2 population, the genetic linkage distance between the AFLP marker and the N gene was estimated. One AFLP marker E39/M41-339 was obtained and transferred to a SCAR marker amplifying a 315 bp DNA fragment linked to the N resistant allele and a 331 bp fragment linked to the N+ susceptible allele. The distance between the molecular marker and the nematodes resistance N gene is 6.3 cM. This research delivered a valuable tool for the marker assisted selection of nematodes resistance in pepper. 相似文献
995.
Cucumber chilling-resistant cultivar Changchun mici and -sensitive cultivar Beijing jietou were used in this study to investigate the effects of exogenous PAs on protection against chilling injury as well as on changes of physiological features, and the fluctuation of free PAs content in the leaves under chilling stress. Upon chilling treatment, free spermidine (Spd), spermine (Spm) and putrescine (Put) were remarkably induced in the leaves of cv. Changchun mici 1 day after treatment. The induction of Put declined thereafter, whereas Spd and Spm levels increased steadily. In the leaves of cv. Beijing jietou, Put content was increased only at 1 day after chilling while Spd content decreased significantly upon chilling treatment. Chilling reduced soluble protein content, and decreased the activities of antioxidant enzymes, including superoxidase dismutase (SOD), peroxidase (POD), catalase (CAT) and ascorbate peroxidase (APX) only in Beijing jietou. However, these changes could be renovated by exogenous application of Put and Spd. It was also found that pretreatment with Put and Spd diminished the increased electrolyte leakage and malondialdehyde (MDA) content caused by chilling in the leaves of both cultivars. Pretreatment of methyglyoxal-bis-(guanylhydrazone) (MGBG), the PAs biosynthetic inhibitor cancelled the effects of PAs in most of the treatments. Moreover, histochemical staining and quantitative measurements showed that exogenous application of Put and Spd eliminated but MGBG exaggerated the hydrogen peroxide (H2O2) accumulation caused by chilling stress, especially in leaves of Beijing jietou. Interestingly, Changchun mici was found to contain higher endogenous free PAs contents compared to Beijing jietou. While no significant difference of SOD, POD and CAT activities was found between non-chilling Changchun mici and Beijing jietou seedlings, the former exhibited higher APX activity than the latter. These results suggest that PAs play important roles in the tolerance of cucumber against chilling stress, which is most likely achieved by acting as oxidative machinery against chilling injury. 相似文献
996.
WEI Chun-ying WANG Meng-hong WEI Yun-feng ZHENG Ze-qi PENG Jing-tian HUANG Jun WEN Yuan WU Zhi-yong 《园艺学报》2009,25(11):2122-2125
AIM: To investigate the effect and the mechanism of apolipoprotein (a) [apo (a)] on proliferation of vascular smooth muscle cells (VSMCs). METHODS: All VSMCs used in experiments were serial subcultured from primary cells and were identified by immunohistochemistry staining of α-actin. Cell growth assay was observed as cell counting and MTT assay. Western blotting was also employed to detect the related mechanism. RESULTS: All cells used in experiments were confirmed as VSMCs. Although apo (a) enhanced VSMCs proliferation, this effect was attenuated by anti-integrin αⅤβ3, LM609. Use these reagents alone had no effect on VSMCs growth. The results of Western blotting demonstrated that focal adhesion kinase (FAK) was activated by apo (a) and the expression of total or phosphorylated transforming growth factor β1 (TGF-β1) was also decreased. However, these effects described above were all blocked by LM609. CONCLUSION: Apolipoprotein (a) enhances VSMCs proliferation and this effect is mediated by integrin αⅤβ3, which activates FAK and attenuates TGF-β1 and phospho-TGF-β1 expression. 相似文献
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刺五加生境与药用成分含量关系的研究进展 总被引:2,自引:2,他引:0
通过文献检索刺五加生境、栽培、光合等对药用成分含量影响研究的相关论文并进行分析总结,讨论生境与刺五加药用成分含量的关系及最佳栽培模式.得知刺五加在野生生境下,黄酮含量与光照呈明显相关,含量呈季节性变化,春秋高,夏季低;皂苷类成分含量则随光强的增大而降低,无季节性变化;其它成分含量无明显的季节变化.较适宜的生境为60%~70%光照,黄酮类与皂苷类均可获得较好的含量与产量.利用不同的栽培密度或遮荫调节光照强度,进行仿生栽培或野生抚育,创造适宜刺五加生活生长的环境条件,并根据其各有效成分在不同部位及不同时期的含量差异,来确定刺五加适宜生产模式及采收期,将有助于刺五加人工栽培产量和药效成分含量的提高. 相似文献