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71.
Yang Song Qing Wang Desheng Wang Jing Yang Hong Li Xiang Wang Xuerong Jin Ruirui Jing Jing-Hua Yang Haichuan Su 《Translational oncology》2018,11(3):691-699
Pancreatic ductal adenocarcinoma (PDAC) is one of the most lethal cancers, with a high mortality rate and poor prognosis. However, little is known concerning the molecular mechanism of PDAC at the proteomics level. Here we report a proteomics analysis of PDAC tumor and adjacent tissues by shotgun proteomics followed by label-free quantification, and in total, 3031 and 3306 proteins were identified in three pairs of PDAC tumor and adjacent tissues, respectively; 40 of them were differentially expressed for at least three-fold in PDAC tumor tissues. Ontological and interaction network analysis highlighted the dysregulation of a set of four proteins in the carboxypeptidase family: carboxypeptidase A1 (CPA1), A2 (CPA2), B1 (CPB1), and chymotrypsin C (CTRC). Western blotting confirmed the downregulation of the carboxypeptidase network in PDAC. Immunohistochemistry of tissue microarray from 90 PDAC patients demonstrated that CPB1 was downregulated 7.07-fold (P < .0001, n = 81) in tumor comparing with the peritumor tissue. Further 208 pancreatic tissues from PDAC tumor, peritumor, and pancreatis confirmed the downregulation of CPB1 in the PDAC patients. In summary, our results displayed that the expression of carboxypeptidase is significantly downregulated in PDAC tumor tissues and may be novel biomarker in the patient with PDAC. 相似文献
72.
表达核糖核酸酶基因的雄性不育油菜的获得 总被引:26,自引:1,他引:25
从细菌Bacillusamyloliquefaciens染色体DNA中克隆了RNase(barnase)基因,构建了TA-29基因5'调控区(-1300-+3)与barnase基因的嵌合基因,通过农杆菌介导的遗传转化,获得了“双低”甘蓝型油菜“中双821”的转基因植株。转化植株与末转化植株在高度、生长速度、花器形态、花色等方面基本相同,但转化植株花丝短小、花药干瘪、没有花粉;自花授粉或以其为父本进行的异花授粉均不能结实,表现为完全的雄性不育。花药的横向解剖结构表明:转基因油菜雄性不育与绒毡层细胞的破坏有关 相似文献
73.
Linyi Liu Bingyu Shi Xinyu Li Xiangqian Wang Xiang Lu Xuerong Cai Ali Huang Guoshun Luo Qidong You Hua Xiang 《Bioorganic & medicinal chemistry》2018,26(15):4537-4543
Btk inhibitors and PI3Kδ inhibitors play crucial roles in the treatment of leukemia, and studies confirmed that the synergetic inhibition against Btk and PI3Kδ could gain an optimal response. Herein, a series of novel benzofuro[3,2-b]pyridin-2(1H)-one derivatives were designed and synthesized as dual Btk/PI3Kδ kinases inhibitors for the treatment of leukemia. Studies indicated that most compounds could suppress the proliferation of multiple leukemia or lymphoma cells (Raji, HL60 and K562 cells) at low micromolar concentrations in vitro. Further kinase assays identified several compounds could simultaneously inhibit Btk kinase and PI3Kδ kinase. Thereinto, compound 16b exhibited the best inhibitory activity (Btk: IC50?=?139?nM; PI3Kδ: IC50?=?275?nM) and showed some selectivity against PI3Kδ compared to PI3Kβ/γ. Finally, the SAR of target compounds was preliminarily discussed combined with docking results. In brief, 16b possessed of the potency for the further optimization as anti-leukemia drugs by inhibiting simultaneously Btk kinase and PI3Kδ kinase. 相似文献
74.
Biocatalytic synthesis of poly(ε‐caprolactone) using modified lipase in ionic liquid media
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Jiugang Yuan Yaping Dai Yuanyuan Yu Ping Wang Qiang Wang Xuerong Fan 《Engineering in Life Science》2016,16(4):371-378
Ionic liquids have been used as exceptional nonaqueous reaction media for enzymatic transformation. The ring‐opening polymerization of ε‐caprolactone catalyzed by Novozyme‐435 lipase was successfully conducted in 1‐butyl‐3‐methylimidazolium hexafluorophosphate ([Bmim]PF6) ionic liquid. 1H‐NMR and MALDI‐TOF analyses of poly(ε‐caprolactone) (PCL) formed by Novozyme‐435 lipase‐catalyzed reaction revealed an asymmetric telechelic α‐hydroxy‐ω‐carboxylic acid end group. The effects of enzyme concentration, temperature, reaction time, and water activities on monomer conversion and Mn were systematically evaluated. Through the optimization of reaction conditions, PCL was produced in 85% monomer conversion, with an Mn of 5942, in [Bmim]PF6 at 60°C for 48 h. DSC results demonstrated that high‐molecular‐weight PCL exhibited an excellent thermal property. SEM results showed that PCL had a clear spherulites structure, which could provide a large surface area for cell adhesion. These results showed that [Bmim]PF6 ionic liquid was suitable for the biocatalytic synthesis of PCL using Novozyme‐435 lipase, and could be used as alternative environmentally friendly media to replace the traditional organic solvents. 相似文献
75.
Characterization of bioscoured cotton fabrics using FT-IR ATR spectroscopy and microscopy techniques 总被引:5,自引:0,他引:5
The effects of bioscouring were investigated by characterizing the chemical and physical surface changes of cotton fabrics using a purified pectinase enzyme from Bacillus subtilis strain WSHB04-02. Fourier-transform infrared (FT-IR) attenuated total-reflectance (ATR) spectroscopy, scanning electron microscopy (SEM), and atomic force microscopy (AFM) techniques were employed. FT-IR ATR spectroscopy provided a fast and semi-quantitative assessment of the removal of pectins and/or waxes on the cotton surface by comparing the changes in intensity of the carbonyl peak induced by HCl vapor treatment at around 1736 cm(-1). The bioscoured surface could be clearly distinguished from those of untreated and alkali-treated cotton fibers using a combination of SEM and AFM. The images produced using these techniques revealed that the surface morphography and topography of the cotton fibers were shaped by the etching action mode of pectinases during bioscouring. These findings demonstrated that AFM is a useful supplement to SEM in characterizing cotton surfaces. 相似文献
76.
Ping Wang Li Cui Qiang Wang Xuerong Fan Xianfei Zhao Jing Wu 《Engineering in Life Science》2010,10(1):19-25
A cutinase from Thermobifida fusca WSH04 and two lipases, L3126 and Lipex 100L, were applied to the enzymatic pretreatment of wool fabrics followed by protease treatment, aiming at hydrolyzing the outmost bound lipids on the wool surface. A mild oxidation with 2 g/L hydrogen peroxide (30%) was selectively carried out before the enzymatic treatments. The cooperative actions of mild oxidation, cutinase and lipase pretreatments during wool processing were investigated. The results showed that lipase pretreatment alone had less impact on the wettability and anti‐felting ability of wool fabrics than cutinase treatment. Combined use of cutinase and lipase pretreatments did not evidently improve the properties of the wool fabric compared with the individual cutinase pretreatment. By contrast, mild oxidation slightly enhanced the activity of cutinase toward the wool surface and promoted the subsequent proteolytic reactions. The wetting time and contact angle of the protease‐treated fabric deceased to 1.2 min and 55°, respectively; the area shrinkage decreased to 3.1%, with an acceptable strength loss from 489 to 418 N. The changes in the cuticle scales of the wool fibers, confirmed by scanning electron microscopy, further proved the cooperative actions of mild oxidation and cutinase pretreatment during enzymatic wool processing. 相似文献
77.
78.
Yue Xie Lili Niu Bo Zhao Qiang Wang Xiang Nong Lin Chen Xuan Zhou Xiaobin Gu Shuxian Wang Xuerong Peng Guangyou Yang 《PloS one》2013,8(12)
Roundworms (Ascaridida: Nematoda), one of the most common soil-transmitted helminths (STHs), can cause ascariasis in various hosts worldwide, ranging from wild to domestic animals and humans. Despite the veterinary and health importance of the Ascaridida species, little or no attention has been paid to roundworms infecting wild animals including non-human primates due to the current taxon sampling and survey bias in this order. Importantly, there has been considerable controversy over the years as to whether Ascaris species infecting non-human primates are the same as or distinct from Ascaris lumbricoides infecting humans. Herein, we first characterized the complete mitochondrial genomes of two representative Ascaris isolates derived from two non-human primates, namely, chimpanzees (Pan troglodytes) and gibbons (Hylobates hoolock), in a zoological garden of southwest China and compared them with those of A. lumbricoides and the congeneric Ascaris suum as well as other related species in the same order, and then used comparative mitogenomics, genome-wide nucleotide sequence identity analysis, and phylogeny to determine whether the parasites from chimpanzees and gibbons represent a single species and share genetic similarity with A. lumbricoides. Taken together, our results yielded strong statistical support for the hypothesis that the chimpanzee- and gibbon-derived Ascaris represent a single species that is genetically similar to A. lumbricoides, consistent with the results of previous morphological and molecular studies. Our finding should enhance public alertness to roundworms originating from chimpanzees and gibbons and the mtDNA data presented here also serves to enrich the resource of markers that can be used in molecular diagnostic, systematic, population genetic, and evolutionary biological studies of parasitic nematodes from either wild or domestic hosts. 相似文献
79.
Hulong Lei Bing Yu Zhiqing Huang Xuerong Yang Zehui Liu Xiangbing Mao Gang Tian Jun He Guoquan Han Hong Chen Qian Mao Daiwen Chen 《Molecular biology reports》2013,40(2):885-892
Recently, increasing evidence supports that adult stem cells are the part of a natural system for tissue growth and repair. This study focused on the differences of mesenchymal stem cells from adult adipose (ADSCs), skeletal muscle (MDSCs) and fetal muscle (FMSCs) in biological characteristics, which is the key to cell therapy success. Stem cell antigen 1 (Sca-1) expression of MDSCs and FMSCs at passage 3 was two times more than that at passage 1 (P < 0.0001). After 28-day myogenic induction, higher expression levels of skeletal muscle-specific genes were observed in MDSCs than FMSCs (P < 0.01), and the lowest expression levels were demonstrated in ADSCs among three cells (P < 0.01). Besides, M-Cad and MyHC expressions in ADSCs were not detected by immunofluorescence or real-time quantitative PCR. Furthermore, after 14 days adipogenic induction, PPARγ2, LPL and aP2 mRNA expressions were higher in ADSCs vs. MDSCs (P < 0.01). Besides, MSCs from adult or fetal muscle expressed higher OCN and OPN than ADSCs after 28 days osteogenic induction (P < 0.01). Taken together, our results suggested that cell source and developmental stage had great impacts on biological properties of mesenchymal stem cells, and proper consideration of all the issues is necessary. 相似文献
80.
Han X Satoh Y Satoh T Matsumoto K Kakuchi T Taguchi S Dairi T Munekata M Tajima K 《Applied microbiology and biotechnology》2011,92(3):509-517
A previously established improved two-phase reaction system has been applied to analyze the substrate specificities and polymerization
activities of polyhydroxyalkanoate (PHA) synthases. We first analyzed the substrate specificity of propionate coenzyme A (CoA)
transferase and found that 2-hydroxybutyrate (2HB) was converted into its CoA derivative. Then, the synthesis of PHA incorporating
2HB was achieved by a wild-type class I PHA synthase from Ralstonia eutropha. The PHA synthase stereoselectively polymerized (R)-2HB, and the maximal molar ratio of 2HB in the polymer was 9 mol%. The yields and the molecular weights of the products
were decreased with the increase of the (R)-2HB concentration in the reaction mixture. The weight-average molecular weight of the polymer incorporating 9 mol% 2HB was
1.00 × 105, and a unimodal peak with polydispersity of 3.1 was observed in the GPC chart. Thermal properties of the polymer incorporating
9 mol% 2HB were analyzed by DSC and TG-DTA. T
g, T
m, and T
d (10%) were observed at −1.1°C, 158.8°C, and 252.7°C, respectively. In general, major components of PHAs are 3-hydroxyalkanoates,
and only engineered class II PHA synthases have been reported as enzymes having the ability to polymerize HA with the hydroxyl
group at C2 position. Thus, this is the first report to demonstrate that wild-type class I PHA synthase was able to polymerize
2HB. 相似文献