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151.
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153.
X. Zhang J. Halder R.P. White D.J. Hughes Z. Ye C. Wang R. Xu B. Gan B.D.L. Fitt 《The Annals of applied biology》2014,164(3):384-395
To estimate potential impact of climate change on wheat fusarium ear blight (FEB), simulated weather for the A1B climate change scenario was input into a model for estimating FEB in central China. In this article, a logistic weather‐based regression model for estimating incidence of wheat FEB in central China was developed, using up to 10 years (2001–2010) of disease, anthesis date and weather data available for 10 locations in Anhui and Hubei provinces. In the model, the weather variables were defined with respect to the anthesis date for each location in each year. The model suggested that incidence of FEB is related to number of days of rainfall in a 30‐day period after anthesis and that high temperatures before anthesis increase the incidence of disease. Validation was done to test whether this relationship was satisfied for another five locations in Anhui province with FEB data for 4–5 years but no nearby weather data, using simulated weather data obtained employing the regional climate modelling system PRECIS. How climate change may affect wheat anthesis date and FEB in central China was investigated for period 2020–2050 using wheat growth model Sirius and climate data simulated using PRECIS. The projection suggested that wheat anthesis dates will generally be earlier and FEB incidence will increase substantially for most locations. 相似文献
154.
Li Liu Jingang Cui Qinbo Yang Chenglin Jia Minqi Xiong Bingbing Ning Xiaoye Du Peiwei Wang Xintong Yu Li Li Wenjian Wang Yu Chen Teng Zhang 《Biochemical and biophysical research communications》2014
Oxidative stress is mechanistically implicated in the pathogenesis of myocardial injury and the subsequent fibrogenic tissue remodeling. Therapies targeting oxidative stress in the process of myocardial fibrogenesis are still lacking and thus remain as an active research area in myocardial injury management. The current study evaluated the effects of a NADPH oxidase inhibitor, apocynin, on the production of reactive oxygen species and the development of myocardial fibrogenesis in isoproterenol (ISO)-induced myocardial injury mouse model. The results revealed a remarkable effect of apocynin on attenuating the development of myocardial necrotic lesions, inflammation and fibrogenesis. Additionally, the protective effects of apocynin against myocardial injuries were associated with suppressed expression of an array of genes implicated in inflammatory and fibrogenic responses. Our study thus provided for the first time the histopathological and molecular evidence supporting the therapeutic value of apocynin against the development of myocardial injuries, in particular, myocardial fibrogenesis, which will benefit the mechanism-based drug development targeting oxidative stress in preventing and/or treating related myocardial disorders. 相似文献
155.
Ming Chen Rui Wang Xi Gan Aiying Lei Chao Li Xiaoli Yu Jun Huang Ting Huang Wanwen Liang 《Molecular biology reports》2010,37(5):2541-2547
Suppression subtractive hybridization library was generated by comparison of cDNA populations isolated from peripheral leukocytes
of pre- and post-immunized tilapia. One cDNA sequence encoding complete inducible cAMP early repressor was obtained from the
library. The sequence was characterized by the presence of the basic structure of ICER IIγ. Expression of ICER was in the
tissues of four types of tilapia was decreased after infection with Streptococcus. After immunization, expression of ICER was initially decreased and then increased after 7 days. In addition, the order for
the overall expression of ICER gene after infection and the increases of ICER expression later after immunization in these
four types of tilapia was positively correlated to the disease resistance and productivity of these four species of tilapia.
Our results provided molecular mechanisms for the different disease resistance capability in different species of tilapia.
In addition, our results also provided reference molecular marker for breeding disease resistant tilapia, cAMP responsive
element modulator. 相似文献
156.
Internalization of Flax Rust Avirulence Proteins into Flax and Tobacco Cells Can Occur in the Absence of the Pathogen 总被引:1,自引:0,他引:1
Maryam Rafiqi Pamela H.P. Gan Michael Ravensdale Gregory J. Lawrence Jeffrey G. Ellis David A. Jones Adrienne R. Hardham Peter N. Dodds 《The Plant cell》2010,22(6):2017-2032
Translocation of pathogen effector proteins into the host cell cytoplasm is a key determinant for the pathogenicity of many bacterial and oomycete plant pathogens. A number of secreted fungal avirulence (Avr) proteins are also inferred to be delivered into host cells, based on their intracellular recognition by host resistance proteins, including those of flax rust (Melampsora lini). Here, we show by immunolocalization that the flax rust AvrM protein is secreted from haustoria during infection and accumulates in the haustorial wall. Five days after inoculation, the AvrM protein was also detected within the cytoplasm of a proportion of plant cells containing haustoria, confirming its delivery into host cells during infection. Transient expression of secreted AvrL567 and AvrM proteins fused to cerulean fluorescent protein in tobacco (Nicotiana tabacum) and flax cells resulted in intracellular accumulation of the fusion proteins. The rust Avr protein signal peptides were functional in plants and efficiently directed fused cerulean into the secretory pathway. Thus, these secreted effectors are internalized into the plant cell cytosol in the absence of the pathogen, suggesting that they do not require a pathogen-encoded transport mechanism. Uptake of these proteins is dependent on signals in their N-terminal regions, but the primary sequence features of these uptake regions are not conserved between different rust effectors. 相似文献
157.
Mattan Hurevich Yftah Tal‐Gan Shoshana Klein Yaniv Barda Alexander Levitzki Chaim Gilon 《Journal of peptide science》2010,16(4):178-185
Cyclization of bioactive peptides, utilizing functional groups serving as natural pharmacophors, is often accompanied with loss of activity. The backbone cyclization approach was developed to overcome this limitation and enhance pharmacological properties. Backbone cyclic peptides are prepared by the incorporation of special building units, capable of forming amide, disulfide and coordinative bonds. Urea bridge is often used for the preparation of cyclic peptides by connecting two amine functionalized side chains. Here we present urea backbone cyclization as an additional method for the preparation of backbone cyclic peptide libraries. A straightforward method for the synthesis of crystalline Fmoc‐Nα [ω‐amino(Alloc)‐alkyl] glycine building units is presented. A set of urea backbone cyclic Glycogen Synthase Kinase 3 analogs was prepared and assessed for protein kinase B inhibition as anticancer leads. Copyright © 2010 European Peptide Society and John Wiley & Sons, Ltd. 相似文献
158.
159.
Germ cells and somatic cells have the identical genome. However, unlike the mortal fate of somatic cells, germ cells have the unique ability to differentiate into gametes that retain totipotency and produce an entire organism upon fertilization. The processes by which germ cells differentiate into gametes, and those by which gametes become embryos, involve dramatic cellular differentiation accompanied by drastic changes in gene expression, which are tightly regulated by genetic circuitries as well as epigenetic mechanisms. Epigenetic regulation refers to heritable changes in gene expression that are not due to changes in primary DNA sequence. The past decade has witnessed an ever-increasing understanding of epigenetic regulation in many different cell types/tissues during embryonic development and adult homeostasis. In this review, we focus on recent discoveries of epigenetic regulation of germ cell differentiation in various metazoan model organisms, including worms, flies, and mammals. 相似文献
160.
Fei-Fei Zhang Lin-Ling Gan Cheng-He Zhou 《Bioorganic & medicinal chemistry letters》2010,20(6):1881-1884
A series of N-substituted carbazole derivatives were synthesized and evaluated for antibacterial and antifungal activities against Staphylococcus aureus, methicillin-resistant Staphylococcus aureus (MRSA), Bacillus subtilis, Escherichia coli, Pseudomonas aeruginosa, Bacillus proteus, Candida albicans and Aspergillus fumigatus by two fold serial dilution technique. Some of the synthesized compounds displayed comparable or even better antibacterial and antifungal activities than reference drugs fluconazole, chloramphenicol and norfloxacin against tested strains. 相似文献