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61.
Berkower I Spadaccini A Chen H Al-Awadi D Muller J Gao Y Feigelstock D Virnik K Ni Y 《Journal of virology》2011,85(5):2439-2448
Native hepatitis B surface antigen (HBsAg) spontaneously assembles into 22-nm subviral particles. The particles are lipoprotein micelles, in which HBsAg is believed to span the lipid layer four times. The first two transmembrane domains, TM1 and TM2, are required for particle assembly. We have probed the requirements for particle assembly by replacing the entire first or third TM domain of HBsAg with the transmembrane domain of HIV gp41. We found that either TM domain of HBsAg could be replaced, resulting in HBsAg-gp41 chimeras that formed particles efficiently. HBsAg formed particles even when both TM1 and TM3 were replaced with the gp41 domain. The results indicate remarkable flexibility in HBsAg particle formation and provide a novel way to express heterologous membrane proteins that are anchored to a lipid surface by their own membrane-spanning domain. The membrane-proximal exposed region (MPER) of gp41 is an important target of broadly reactive neutralizing antibodies against HIV-1, and HBsAg-MPER particles may provide a good platform for future vaccine development. 相似文献
62.
Yalan Chen Zhangliu Du Zhe Weng Ke Sun Yuqin Zhang Qin Liu Yan Yang Yang Li Zhibo Wang Yu Luo Bo Gao Bin Chen Zezhen Pan Lukas Van Zwieten 《Global Change Biology》2023,29(18):5445-5459
To achieve long-term increases in soil organic carbon (SOC) storage, it is essential to understand the effects of carbon management strategies on SOC formation pathways, particularly through changes in microbial necromass carbon (MNC) and dissolved organic carbon (DOC). Using a 14-year field study, we demonstrate that both biochar and maize straw lifted the SOC ceiling, but through different pathways. Biochar, while raising SOC and DOC content, decreased substrate degradability by increasing carbon aromaticity. This resulted in suppressed microbial abundance and enzyme activity, which lowered soil respiration, weakened in vivo turnover and ex vivo modification for MNC production (i.e., low microbial carbon pump “efficacy”), and led to lower efficiency in decomposing MNC, ultimately resulting in the net accumulation of SOC and MNC. In contrast, straw incorporation increased the content and decreased the aromaticity of SOC and DOC. The enhanced SOC degradability and soil nutrient content, such as total nitrogen and total phosphorous, stimulated the microbial population and activity, thereby boosting soil respiration and enhancing microbial carbon pump “efficacy” for MNC production. The total C added to biochar and straw plots were estimated as 27.3–54.5 and 41.4 Mg C ha−1, respectively. Our results demonstrated that biochar was more efficient in lifting the SOC stock via exogenous stable carbon input and MNC stabilization, although the latter showed low “efficacy”. Meanwhile, straw incorporation significantly promoted net MNC accumulation but also stimulated SOC mineralization, resulting in a smaller increase in SOC content (by 50%) compared to biochar (by 53%–102%). The results address the decadal-scale effects of biochar and straw application on the formation of the stable organic carbon pool in soil, and understanding the causal mechanisms can allow field practices to maximize SOC content. 相似文献
63.
Construction of a recombinant BHV-1 expressing the VP1 gene of foot and mouth disease virus and its immunogenicity in a rabbit model 总被引:1,自引:0,他引:1
Xian-Gang Ren Fei Xue Yuan-Mao Zhu Guang-Zhi Tong Yan-Hui Wang Jun-Ke Feng Hong-Fei Shi Yu-Ran Gao 《Biotechnology letters》2009,31(8):1159-1165
Foot-and-mouth disease (FMD) and infectious bovine rhinotracheitis (IBR) are two important infectious diseases of cattle.
Using bovine herpesvirus type 1 (BHV-1) as a gene delivery vector for development of live-viral vaccines has gained widespread
interest. In this study, a recombinant BHV-1 was constructed by inserting the synthetic FMDV (O/China/99) VP1 gene in the
the gE locus of BHV-1 genome under the control of immediately early gene promoter of human cytomegalovirus (phIE CMV) and
bovine growth hormone polyadenylation (BGH polyA) signal. After homologous recombination and plaque purification, a recombinant
virus named BHV-1/gE−/VP1 was acquired and identified. The immunogenicity was confirmed in a rabbit model by virus neutralization test and enzyme-linked
immunosorbent assay (ELISA). The result indicated that the BHV-1/gE−/VP1 has the potential for being developed as a bivalent vaccine for FMD and IBR. 相似文献
64.
Cuicui Li Bingsheng Qin Yunfeng Zhang Alberto Varzi Stefano Passerini Jiaying Wang Jiaming Dong Danli Zeng Zhihong Liu Hansong Cheng 《Liver Transplantation》2019,9(10)
Herein, a novel electrospun single‐ion conducting polymer electrolyte (SIPE) composed of nanoscale mixed poly(vinylidene fluoride‐co‐hexafluoropropylene) (PVDF‐HFP) and lithium poly(4,4′‐diaminodiphenylsulfone, bis(4‐carbonyl benzene sulfonyl)imide) (LiPSI) is reported, which simultaneously overcomes the drawbacks of the polyolefin‐based separator (low porosity and poor electrolyte wettability and thermal dimensional stability) and the LiPF6 salt (poor thermal stability and moisture sensitivity). The electrospun nanofiber membrane (es‐PVPSI) has high porosity and appropriate mechanical strength. The fully aromatic polyamide backbone enables high thermal dimensional stability of es‐PVPSI membrane even at 300 °C, while the high polarity and high porosity ensures fast electrolyte wetting. Impregnation of the membrane with the ethylene carbonate (EC)/dimethyl carbonate (DMC) (v:v = 1:1) solvent mixture yields a SIPE offering wide electrochemical stability, good ionic conductivity, and high lithium‐ion transference number. Based on the above‐mentioned merits, Li/LiFePO4 cells using such a SIPE exhibit excellent rate capacity and outstanding electrochemical stability for 1000 cycles at least, indicating that such an electrolyte can replace the conventional liquid electrolyte–polyolefin combination in lithium ion batteries (LIBs). In addition, the long‐term stripping–plating cycling test coupled with scanning electron microscope (SEM) images of lithium foil clearly confirms that the es‐PVPSI membrane is capable of suppressing lithium dendrite growth, which is fundamental for its use in high‐energy Li metal batteries. 相似文献
65.
Zheng P Gao HC Li Q Shao WH Zhang ML Cheng K Yang de Y Fan SH Chen L Fang L Xie P 《Journal of proteome research》2012,11(3):1741-1748
Major depressive disorder (MDD) is a socially detrimental psychiatric disorder, contributing to increased healthcare expenditures and suicide rates. However, no empirical laboratory-based tests are available to support the diagnosis of MDD. In this study, a NMR-based plasma metabonomic method for the diagnosis of MDD was tested. Proton nuclear magnetic resonance ((1)H NMR) spectra of plasma sampled from first-episode drug-na??ve depressed patients (n = 58) and healthy controls (n = 42) were recorded and analyzed by orthogonal partial least-squares discriminant analysis (OPLS-DA). The OPLS-DA score plots of the spectra demonstrated that the depressed patient group was significantly distinguishable from the healthy control group. Moreover, the method accurately diagnosed blinded samples (n = 26) in an independent replication cohort with a sensitivity and specificity of 92.8% and 83.3%, respectively. Taken together, NMR-based plasma metabonomics may offer an accurate empirical laboratory-based method applicable to the diagnosis of MDD. 相似文献
66.
The Hfq protein is reported to be an RNA chaperone, which is involved in the stress response and the virulence of several pathogens. In E. coli, Hfq can mediate the interaction between some sRNAs and their target mRNAs. But it is controversial whether Hfq plays an important role in S. aureus. In this study, we found that the deletion of hfq gene in S. aureus 8325-4 can increase the surface carotenoid pigments. The hfq mutant was more resistant to oxidative stress but the pathogenicity of the mutant was reduced. We reveal that the Hfq protein can be detected only in some S. aureus strains. Using microarray and qRT-PCR, we identified 116 genes in the hfq mutant which had differential expression from the wild type, most of which are related to the phenotype and virulence of S. aureus. Among the 116 genes, 49 mRNAs can specifically bind Hfq protein, which indicates that Hfq also acts as an RNA binding protein in S. aureus. Our data suggest that Hfq protein of S. aureus is a multifunctional regulator involved in stress and virulence. 相似文献
67.
Shuang-Xia Zhao Chun-Ming Pan Huang-Ming Cao Bing Han Jing-Yi Shi Jun Liang Guan-Qi Gao Yong-De Peng Qing Su Jia-Lun Chen Jia-Jun Zhao Huai-Dong Song 《PloS one》2010,5(3)
To determine whether genetic heterogeneity exists in patients with Graves'' disease (GD), the cytotoxic T-lymphocyte associated 4 (CTLA-4) gene, which is implicated a susceptibility gene for GD by considerable genetic and immunological evidence, was used for association analysis in a Chinese Han cohort recruited from various geographic regions. Our association study for the SNPs in the CTLA4 gene in 2640 GD patients and 2204 control subjects confirmed that CTLA4 is the susceptibility gene for GD in the Chinese Han population. Moreover, the logistic regression analysis in the combined Chinese Han cohort revealed that SNP rs231779 (allele frequencies p = 2.81×10−9, OR = 1.35, and genotype distributions p = 2.75×10−9, OR = 1.42) is likely the susceptibility variant for GD. Interestingly, the logistic regression analysis revealed that SNP rs35219727 may be the susceptibility variant to GD in the Shandong population; however, SNP, rs231779 in the CTLA4 gene probably independently confers GD susceptibility in the Xuzhou and southern China populations. These data suggest that the susceptibility variants of the CTLA4 gene varied between the different geographic populations with GD. 相似文献
68.
Ni Zeng Tao Wang Mei Chen Zhicheng Yuan Jiangyue Qin Yanqiu Wu Lijuan Gao Yongchun Shen Lei Chen Fuqiang Wen 《Journal of cellular and molecular medicine》2019,23(8):5532-5541
As a novel kind of non‐coding RNA, circular RNAs (circRNAs) were involved in various biological processes. However, the role of circRNAs in the developmental process of chronic obstructive pulmonary disease (COPD) is still unclear. In the present study, by using a cell model of COPD in primary human small airway epithelial cells (HSAECs) treated with or without cigarette smoke extract (CSE), we uncovered 4,379 previously unknown circRNAs in human cells and 903 smoke‐specific circRNAs, with the help of RNA‐sequencing and bioinformatic analysis. Moreover, 3,872 up‐ and 4,425 down‐regulated mRNAs were also identified under CSE stimulation. Furthermore, a putative circRNA‐microRNA‐mRNA network was constructed for in‐depth mechanism exploration, which indicated that differentially expressed circRNAs could influence expression of some key genes that participate in response to pentose phosphate pathway, ATP‐binding cassette (ABC) transporters, glycosaminoglycan biosynthesis pathway and cancer‐related pathways. Our research indicated that cigarette smoke had an influence on the biogenesis of circRNAs and mRNAs. CircRNAs might be involved in the response to CSE in COPD through the circRNA‐mediated ceRNA networks. 相似文献
69.
为了探讨中性粒细胞明胶酶相关脂质运载蛋白(neutrophil gelatinase-associated lipocalin, NGAL)和肾损伤分子-1 (kidney injury molecule-1, KIM-1)以及血肌酐(serum creatinine, SCr)联合检测对慢性肾病(chronic kidney disease, CKD)的早期诊断价值,本研究收集260例肾病患者和85例健康体检者,检测其血清NGAL、KIM-1和SCr水平。依据肾功能分级标准,CKD患者分为CKD 1期(53例),CKD 2期(68例),CKD 3期(71例),CKD 4期(46例)和CKD 5期(22例),并分析以上指标在各组间的含量差异,及其联合测定对CKD早期的敏感性。与健康对照组相比较,CKD 1期、CKD 2期、3期、4期和5期患者的NGAL、KIM-1水平均明显升高(p<0.001)。血清SCr含量在CKD 3期、4期和5期组较健康对照组显著增加(p<0.001)。以上3项指标均随着CKD严重程度增加而升高。各组指标阳性率分析显示,3项联合检测阳性率高于单项检测阳性率。ROC曲线分析NGAL、KIM-1、SCr对CKD诊断的AUC值F分别是为0.824、0.805、0.856。相关性分析结果显示,GFR和NGAL、KIM-1、SCr相关系数分别是r=-0.784、-0.756、-0.728 (p<0.05)。NGAL与KIM-1、SCr的相关系数分别是r=0.932、0.764 (p<0.05);KIM-1与SCr的相关系数r分别是0.791 (p<0.05)。本研究初步得出结论:血清NGAL、Kim-1可作为CKD早期诊断的重要指标,联合检测血清NGAL、Kim-1、SCr可有效提高CKD早期肾损伤诊断的敏感度,对CKD的分期诊断和治疗具有极其重要的临床价值。 相似文献
70.
Grace X. Ma Steve Shive Yin Tan Wanzhen Gao Joanne Rhee Micah Park Jaesool Kim Jamil I. Toubbeh 《Cancer epidemiology》2009,33(5):381-386
Background: Despite evidence of a decline in both incidence and prevalence of colorectal cancer nationwide, it remains the second most commonly diagnosed cancer and the third highest cause of mortality among Asian Americans, including Korean Americans. This community-based and theoretically guided study evaluated a culturally appropriate intervention program that included a bilingual cancer educational program among Korean Americans including information on CRC risks, counseling to address psychosocial and access barriers, and patient navigation assistance. Methods: A two-group quasi-experimental design with baseline and post-intervention assessment and a 12-month follow-up on screening was used in the study. Korean Americans (N = 167) were enrolled from six Korean churches. The intervention group received culturally appropriate intervention program addressing accessibility and psychosocial barriers, and navigation assistance for screening. The control group received general health education that included cancer-related health issues and screening. Results: There was a significant difference (p < 0.05) between the post-intervention and control groups in awareness of CRC risk factors. There was also a significant improvement in the pre–post across HBM measures in the intervention group for perceived susceptibility (p < 0.05) and benefits and barriers to screening (p < 0.001). At baseline, 13% of participants in the intervention group and 10% in control group reported having had a CRC cancer screening test in the previous year. At the 12-month post-intervention follow-up, 77.4% of participants in the intervention group had obtained screening compared to 10.8% in the control group. Conclusion: While health disparities result from numerous factors, a culturally appropriate and church-based intervention can be highly effective in increasing knowledge of and access to, and in reducing barriers to CRC screening among underserved Koreans. 相似文献