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1.
A critical factor in clinical development of cancer immunotherapies is the identification of tumor-associated antigens that may be related to immunotherapy potency. In this study, protein microarrays containing >8,000 human proteins were screened with serum from prostate cancer patients (N = 13) before and after treatment with a granulocyte–macrophage colony-stimulating factor (GM-CSF)-secreting whole cell immunotherapy. Thirty-three proteins were identified that displayed significantly elevated (P ≤ 0.05) signals in post-treatment samples, including three proteins that have previously been associated with prostate carcinogenesis, galectin-8, T-cell alternative reading frame protein (TARP) and TNF-receptor-associated protein 1 (TRAP1). Expanded analysis of antibody induction in metastatic, castration-resistant prostate cancer (mCRPC) patients (N = 92) from two phase 1/2 trials of prostate cancer immunotherapy, G-9803 and G-0010, indicated a significant (P = 0.03) association of TARP antibody induction and median survival time (MST). Antibody induction to TARP was also significantly correlated (P = 0.036) with an increase in prostate-specific antigen doubling time (PSADT) in patients with a biochemical (PSA) recurrence following prostatectomy or radiation therapy (N = 19) from in a previous phase 1/2 trial of prostate cancer immunotherapy, G-9802. RNA and protein encoding TARP and TRAP1 was up-regulated in prostate cancer tissue compared to matched normal controls. These preliminary findings suggest that antibody induction to TARP may represent a possible biomarker for treatment response to GM-CSF secreting cellular immunotherapy in prostate cancer patients and demonstrates the utility of using protein microarrays for the high-throughput screening of patient-derived antibody responses.  相似文献   
2.
Many studies have examined the association between the FABP2 (rs1799883) Ala54Thr gene polymorphism and type 2 diabetes mellitus risk (T2DM) in various populations, but their results have been inconsistent. To assess this relationship more precisely, A HuGE review and meta‐analysis were performed. The PubMed and CNKI database was searched for case‐control studies published up to April 2014. Data were extracted and pooled odds ratios (OR) with 95% confidence intervals (CI) were calculated. Ultimately, 13 studies, comprising 2020 T2DM cases and 2910 controls were included. Overall, for the Thr carriers (Ala/Thr and Thr/Thr) versus the wild‐type homozygotes (Ala/Ala), the pooled OR was 1.18 (95% CI = 1.04–1.34, P = 0.062 for heterogeneity), for Thr/Thr versus Ala/Ala the pooled OR was 1.17 (95% CI = 1.05–1.41 P = 0.087 for heterogeneity). In the stratified analysis by ethnicity, the significantly risks were found among Asians but not Caucasians. This meta‐analysis suggests that the FABP2 (rs1799883) Ala54Thr polymorphisms are associated with increased susceptibility to T2DM risk among Asians but not Caucasians.  相似文献   
3.
Caveolin induces membrane curvature and drives the formation of caveolae that participate in many crucial cell functions such as endocytosis. The central portion of caveolin-1 contains two helices (H1 and H2) connected by a three-residue break with both N- and C-termini exposed to the cytoplasm. Although a U-shaped configuration is assumed based on its inaccessibility by extracellular matrix probes, caveolin structure in a bilayer remains elusive. This work aims to characterize the structure and dynamics of caveolin-1 (D82–S136; Cav182–136) in a DMPC bilayer using NMR, fluorescence emission measurements, and molecular dynamics simulations. The secondary structure of Cav182–136 from NMR chemical shift indexing analysis serves as a guideline for generating initial structural models. Fifty independent molecular dynamics simulations (100 ns each) are performed to identify its favorable conformation and orientation in the bilayer. A representative configuration was chosen from these multiple simulations and simulated for 1 μs to further explore its stability and dynamics. The results of these simulations mirror those from the tryptophan fluorescence measurements (i.e., Cav182–136 insertion depth in the bilayer), corroborate that Cav182–136 inserts in the membrane with U-shaped conformations, and show that the angle between H1 and H2 ranges from 35 to 69°, and the tilt angle of Cav182–136 is 27 ± 6°. The simulations also reveal that specific faces of H1 and H2 prefer to interact with each other and with lipid molecules, and these interactions stabilize the U-shaped conformation.  相似文献   
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为了解抗菌肽在饵料微藻中表达后的抗菌特性,构建海洋微拟球藻(Nannochloropsis oceanica)、湖泊微拟球藻(N.limnetica)和三角褐指藻(Phaeodactylum tricornutum)的抗菌肽(源自虹鳟,Cath-1a)表达质粒,分别转化相应的微藻,检测转化子中抗菌肽的表达量和体外抑菌效果,将藻株作为鱼饲料添加剂喂食斑马鱼,初步分析了抗菌肽及藻体自身的岩藻黄素和多不饱和脂肪酸对鱼免疫系统的影响。结果表明,外源抗菌肽在3种微藻中均可以成功表达,体外抑菌试验表明,仅三角褐指藻对水产领域常见致病菌爱德华氏菌(Edwardsiella tarda)有一定的抑菌效果,然而抗菌肽的表达并未使3种藻株的体外抑菌性增加。添加藻粉对斑马鱼的生长无明显影响,通过检测鱼体肝脏中与抗氧化和免疫相关基因的表达水平及丙二醛的含量,表明添加藻粉可增强斑马鱼的抗氧化和抗炎症能力,表达抗菌肽(PtC组)能进一步提高斑马鱼的免疫力。另外,添加Pt6(富含岩藻黄素)藻粉组比添加PtC的抗炎效果更显著,表明三角褐指藻中的岩藻黄素和二十碳五烯酸对增强鱼的抗病能力具有潜在作用。  相似文献   
6.
转运蛋白是一类膜蛋白,可介导生物膜内外化学物质的跨膜转运及信号交换。有机酸转运蛋白在微生物有机酸代谢的跨膜转运过程中发挥重要作用,根据转运蛋白有机酸转运的方向不同可以分为摄取转运蛋白和外排转运蛋白。在微生物代谢中,有些有机酸可以作为能源直接参与体内代谢,有些是能量转换过程中的重要中间产物;摄取转运蛋白的过表达,可以促进微生物细胞获取能源物质,高效的生产目标产物;有机酸摄取转运蛋白敲除或外排转运蛋白表达,有利于底盘细胞外排更多目标产物,进而促进有机酸的生物合成。研究有机酸转运蛋白的结构和功能,有助于解析微生物细胞有机酸生物合成及利用的机制,对于提高工业微生物对有机酸的利用及生物合成具有重要作用。本文综述了微生物有机酸转运蛋白分类和结构、转运方式和转运功能等方面,重点综述了转运蛋白在有机酸生产中的应用,为工业微生物有机酸的高效生物合成及未来发展提供参考。  相似文献   
7.
Sheath blight (ShB) severely threatens rice cultivation and production; however, the molecular mechanism of rice defence against ShB remains unclear. Screening of transposon Ds insertion mutants identified that Calcineurin B-like protein-interacting protein kinase 31 (CIPK31) mutants were more susceptible to ShB, while CIPK31 overexpressors (OX) were less susceptible. Sequence analysis indicated two haplotypes of CIPK31: Hap_1, with significantly higher CIPK31 expression, was less sensitive to ShB than the Hap_2 lines. Further analyses showed that the NAF domain of CIPK31 interacted with the EF-hand motif of respiratory burst oxidase homologue (RBOHA) to inhibit RBOHA-induced H2O2 production, and RBOHA RNAi plants were more susceptible to ShB. These data suggested that the CIPK31-mediated increase in resistance is not associated with RBOHA. Interestingly, the study also found that CIPK31 interacted with catalase C (CatC); cipk31 mutants accumulated less H2O2 while CIPK31 OX accumulated more H2O2 compared to the wild-type control. Further analysis showed the interaction of the catalase domain of CatC with the NAF domain of CIPK31 by which CIPK31 inhibits CatC activity to accumulate more H2O2.  相似文献   
8.
Flowering time is one of important agronomic traits determining the crop yield and affected by high temperature. When facing high ambient temperature, plants often initiate early flowering as an adaptive strategy to escape the stress and ensure successful reproduction. However, here we find opposing ways in the short-day crop soybean to respond to different levels of high temperatures, in which flowering accelerates when temperature changes from 25 to 30 °C, but delays when temperature reaches 35 °C under short day. phyA-E1, possibly photoperiodic pathway, is crucial for 35 °C-mediated late flowering, however, does not contribute to promoting flowering at 30 °C. 30 °C-induced up-regulation of FT2a and FT5a leads to early flowering, independent of E1. Therefore, distinct responsive mechanisms are adopted by soybean when facing different levels of high temperatures for successful flowering and reproduction.  相似文献   
9.
土壤中镉(Cd)含量的超标导致了土壤生态系统的恶性发展,微生物作为土壤中的常见组分之一在缓解土壤镉污染中展现出巨大潜力。本文总结了微生物、微生物-植物和微生物-生物炭在镉污染土壤修复中的应用并阐述了相关的作用机理。芽孢杆菌(Bacillus)、不动杆菌(Acinetobacter)、荧光假单胞菌(Pseudomonas fluorescence)、丛枝菌根真菌(arbuscular mycorrhizal fungi,AMF)等微生物可以通过吸附、矿化、沉淀、溶解等方式改变镉的生物有效性,从而达到缓解镉污染的目的。pH值、温度、微生物生物量、镉初始浓度以及时间等对微生物降低镉的生物有效性方面有着显著的影响。假单胞菌、伯克霍尔德菌(Burkholderia)、黄杆菌(flavobacterium)等微生物可以通过促生、活化等作用促进超富集植物对Cd2+的吸收。生物炭作为一种土壤改良剂,其独有的理化性质可以作为微生物的庇护所。微生物-生物炭联合使用与单用生物炭相比可以进一步促进镉的残渣态的增加,降低土壤中有效态的比例。  相似文献   
10.
Fruit spine is an important quality trait of cucumber. To better understand the molecular basis of cucumber spine development and function, RNA-Seq was performed to identify differentially expressed genes (DEGs) in fruit spines of different development stages, namely, 8 days before anthesis (SpBA8), anthesis (SpA) and 8 days after anthesis (SpAA8). Stage-wise comparisons obtained 2,259 (SpBA8 vs. SpA), 4,551 (SpA vs. SpAA8), and 5,290 (SpBA8 vs. SpAA8) DEGs. All the DEGs were classified into eight expression clusters by trend analysis. Among these DEGs, in addition to the Mict, Tril, CsTTG1, CsMYB6, NS, and Tu genes that have been reported to regulate fruit spine formation, we found that the CsHDG11, CsSCL8, CsSPL8, CsZFP6 and CsZFP8 may also be involved in spine development in cucumber. Our study provides a theoretical basis for further research on molecular mechanisms of spine development in cucumber.  相似文献   
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