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31.
Zheng Liu Ning Sun Shangjun Yang Yanhong Zhao Xiaoqin Wang Xingyu Hao Zhijun Qiao 《Biologia》2013,68(4):577-586
Compared with C3 plants, C4 plants possess a mechanism to concentrate CO2 around the ribulose-1,5-bisphosphate carboxylase/oxygenase in chloroplasts of bundle sheath cells so that the carboxylation reaction work at a much more efficient rate, thereby substantially eliminate the oxygenation reaction and the resulting photorespiration. It is observed that C4 photosynthesis is more efficient than C3 photosynthesis under conditions of low atmospheric CO2, heat, drought and salinity, suggesting that these factors are the important drivers to promote C4 evolution. Although C4 evolution took over 66 times independently, it is hypothesized that it shared the following evolutionary trajectory: 1) gene duplication followed by neofunctionalization; 2) anatomical and ultrastructral changes of leaf architecture to improve the hydraulic systems; 3) establishment of two-celled photorespiratory pump; 4) addition of transport system; 5) co-option of the duplicated genes into C4 pathway and adaptive changes of C4 enzymes. Based on our current understanding on C4 evolution, several strategies for engineering C4 rice have been proposed to increase both photosynthetic efficiency and yield significantly in order to avoid international food crisis in the future, especially in the developing countries. Here we summarize the latest progresses on the studies of C4 evolution and discuss the strategies to introduce two-celled C4 pathway into rice. 相似文献
32.
Qiao Sun Yiwu Yao Chunping Liu Hua Li Hequan Yao Xiaowen Xue Jinsong Liu Zhengchao Tu Sheng Jiang 《Bioorganic & medicinal chemistry letters》2013,23(11):3295-3299
We report the design, synthesis, and biological evaluation of a new series of HDAC1 inhibitors using click chemistry. Compound 17 bearing a phenyl ring at meta-position was identified to show much better selectivity for HDAC1 over HDAC7 than SAHA. The compond 17 also showed better in vitro anticancer activities against several cancer cell lines than that of SAHA. This work could serve as a foundation for further exploration of selective HDAC inhibitors using the compound 17 molecular scaffold. 相似文献
33.
34.
Kun Qiao Shi Guo Li Hong Yan Li Shao Ming Tong He Sheng Hou 《Journal of applied phycology》2013,25(1):81-87
The methionine adenosyltransferase gene (MAT) had been isolated from an economic seaweed Undaria pinnatifida by PCR using degenerate primers. The cDNA was 1,491 bp in length with an open reading frame of 1,194 nucleotides, encoding a deduced protein of 397 amino acids. The protein had a predicted molecular weight of 43.2 kDa, and the isoelectric point was 5.244. The sequence contains a 92 bp 5′-untranslated region (UTR) and a 205 bp 3′-UTR. The methionine adenosyltransferase (MAT) sequence of U. pinnatifida (UpMAT) shared 68–92 % identities with the previous published MAT sequences of other species. Phylogenetic analysis indicated that the phylogenetic relationship of UpMAT with some other seaweeds was closer than with those of higher plants. Under different stress conditions, the relative mRNA expression levels of the MAT of U. pinnatifida (UpMAT) were measured by real-time quantitative PCR, and the results demonstrated that the UpMAT might help to protect the alga against various abiotic stresses. 相似文献
35.
Juan Lin Hanjie Li Min Yang Junming Ren Zhe Huang Felicia Han Jian Huang Jianhui Ma Duanwu Zhang Zhirong Zhang Jianfeng Wu Deli Huang Muzhen Qiao Guanghui Jin Qiao Wu Yinghui Huang Jie Du Jiahuai Han 《Cell reports》2013,3(1):200-210
Highlights? RIP3 deficiency in macrophages reduces advanced atherosclerotic lesions ? RIP3 deficiency reduces primary necrosis of macrophages in advanced lesions ? RIP3-dependent macrophage necrosis is not postapoptotic cell death ? Increased RIP3 converts apoptosis to necrosis in advanced lesional macrophages 相似文献
36.
Xi Li Ti-Cao Zhang Qin Qiao Zhumei Ren Jiayuan Zhao Takahiro Yonezawa Masami Hasegawa M. James C Crabbe Jianqiang Li Yang Zhong 《PloS one》2013,8(3)
Background
The central function of chloroplasts is to carry out photosynthesis, and its gene content and structure are highly conserved across land plants. Parasitic plants, which have reduced photosynthetic ability, suffer gene losses from the chloroplast (cp) genome accompanied by the relaxation of selective constraints. Compared with the rapid rise in the number of cp genome sequences of photosynthetic organisms, there are limited data sets from parasitic plants.Principal Findings/Significance
Here we report the complete sequence of the cp genome of Cistanche deserticola, a holoparasitic desert species belonging to the family Orobanchaceae. The cp genome of C. deserticola is greatly reduced both in size (102,657 bp) and in gene content, indicating that all genes required for photosynthesis suffer from gene loss and pseudogenization, except for psbM. The striking difference from other holoparasitic plants is that it retains almost a full set of tRNA genes, and it has lower dN/dS for most genes than another close holoparasitic plant, E. virginiana, suggesting that Cistanche deserticola has undergone fewer losses, either due to a reduced level of holoparasitism, or to a recent switch to this life history. We also found that the rpoC2 gene was present in two copies within C. deserticola. Its own copy has much shortened and turned out to be a pseudogene. Another copy, which was not located in its cp genome, was a homolog of the host plant, Haloxylon ammodendron (Chenopodiaceae), suggesting that it was acquired from its host via a horizontal gene transfer. 相似文献37.
In this study, we prepared nano-hydroxyapatite/polyamide 66/glass fibre (n-HA/PA66/GF) bioactive bone screws. The microstructure, morphology and coating of the screws were characterised, and the adhesion, proliferation and viability of MC3T3-E1 cells on n-HA/PA66/GF scaffolds were determined using scanning electron microscope, CCK-8 assays and cellular immunofluorescence analysis. The results confirmed that n-HA/PA66/GF scaffolds were biocompatible and had no negative effect on MC3T3-E1 cells in vitro. To investigate the in vivo biocompatibility, internal fixation properties and osteogenesis of the bioactive screws, both n-HA/PA66/GF screws and metallic screws were used to repair intercondylar femur fractures in dogs. General photography, CT examination, micro-CT examination, histological staining and biomechanical assays were performed at 4, 8, 12 and 24 weeks after operation. The n-HA/PA66/GF screws exhibited good biocompatibility, high mechanical strength and extensive osteogenesis in the host bone. Moreover, 24 weeks after implantation, the maximum push-out load of the bioactive screws was greater than that of the metallic screws. As shown by their good cytocompatibility, excellent biomechanical strength and fast formation and ingrowth of new bone, n-HA/PA66/GF screws are thus suitable for orthopaedic clinical applications. 相似文献
38.
Background
Right internal jugular vein (IJV) is a preferred access route for tunneled (cuffed) dialysis catheters (TDCs), and both right external jugular vein (EJV) and left IJV are alternative routes for patients in case the right IJV isn’t available for TDC placement. This retrospective study aimed to determine if a disparity exists between the two alternative routes in hemodialysis patients in terms of outcomes of TDCs.Methods
49 hemodialysis patients who required TDCs through right EJV (n = 21) or left IJV (n = 28) as long-term vascular access were included in this study. The primary end point was cumulative catheter patency. Secondary end points include primary catheter patency, proportion of patients that never required urokinase and incidence of catheter-related bloodstream infections (CRBSI).Results
A total of 20,870 catheter-days were evaluated and the median was 384 (interquartile range, 262–605) catheter-days. Fewer catheters were removed in the right EJV group than in the left IJV group (P = 0.007). Mean cumulative catheter patency was higher in the right EJV group compared with the left IJV group (P = 0.031). There was no significant difference between the two groups in the incidence of CRBSI, primary catheter patency or proportion of patients that never required urokinase use. Total indwell time of antecedent catheters was identified as an independent risk factor for cumulative catheter patency by Cox regression hazards test with an HR of 2.212 (95% CI, 1.363–3.588; p = 0.001).Conclusions
Right EJV might be superior to left IJV as an alternative insertion route for TDC placement in hemodialysis patients whose right IJVs are unavailable. 相似文献39.
Highly Active and Stable Graphene Tubes Decorated with FeCoNi Alloy Nanoparticles via a Template‐Free Graphitization for Bifunctional Oxygen Reduction and Evolution 下载免费PDF全文
Shiva Gupta Liang Qiao Shuai Zhao Hui Xu Ye Lin Surya V. Devaguptapu Xianliang Wang Mark T. Swihart Gang Wu 《Liver Transplantation》2016,6(22)
Development of highly active and stable bifunctional oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) catalysts from earth‐abundant elements remains a grand challenge for highly demanded reversible fuel cells and metal–air batteries. Carbon catalysts have many advantages over others due to their low cost, excellent electrical conductivity, high surface area, and easy functionalization. However, they typically cannot withstand the highly oxidative OER environment. Here, a new class of bifunctional electrocatalyst is reported, consisting of ultralarge sized nitrogen doped graphene tubes (N‐GTs) (>500 nm) decorated with FeCoNi alloy particles. These tubes are prepared from an inexpensive precursor, dicyandiamide, via a template‐free graphitization process. The ORR/OER activity and the stability of these graphene tube catalysts depend strongly on the transition metal precursors. The best performing FeCoNi‐derived N‐GT catalyst exhibits excellent ORR and OER activity along with adequate electrochemical durability over a wide potential window (0–1.9 V) in alkaline media. The measured OER current is solely due to desirable O2 evolution, rather than carbon oxidation. Extensive electrochemical and physical characterization indicated that high graphitization degree, thicker tube walls, proper nitrogen doping, and presence of FeCoNi alloy particles are vital for high bifunctional activity and electrochemical durability of tubular carbon catalysts. 相似文献
40.
Qiao Liya Zhang Xifang Jan Catherine Li Xiaoxia Li Meng Wang Huaizhou 《中国科学:生命科学英文版》2019,62(7):930-936
Optical coherence tomography angiography(Angio-OCT) has introduced a new non-invasive, quantitative method to assess superficial and deep capillary networks of the retina. In this study, we investigated macular retinal thickness and flow density change following posterior scleral reinforcement(PSR) surgery, using an RTVue XR Avanti Angio-OCT, in patients with pathological myopia. A total of 13 patients with pathological myopia were recruited and all patients completed the 6 months follow-up visit. Data from 22 eyes were used in this study. The mean age was 36.23±15.29 years, and 43%(n=6) were men.Spherical equivalent refractive error(SE) ranged from –8.0 to –24.0 D. Postoperative axial length, best-corrected visual acuity and SE did not change significantly at each follow-up, compared with pre-operative measures(P0.05). Postoperative flow density of superficial and deep retinal layers at each sector did not change significantly at each follow-up, compared with preoperative measures(P0.05). However, we found significant decrease in retinal thickness of parafovea-inferior sector after PSR surgery(P0.01), indicating potential relaxation of vitreofoveal traction after PSR surgery. 相似文献