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101.
We conducted a phase 1 double-blind randomised controlled trial (RCT) of a HIV-1 envelope protein (CN54 gp140) candidate vaccine delivered vaginally to assess immunogenicity and safety. It was hypothesised that repeated delivery of gp140 may facilitate antigen uptake and presentation at this mucosal surface. Twenty two healthy female volunteers aged 18-45 years were entered into the trial, the first receiving open-label active product. Subsequently, 16 women were randomised to receive 9 doses of 100 μg of gp140 in 3 ml of a Carbopol 974P based gel, 5 were randomised to placebo solution in the same gel, delivered vaginally via an applicator. Participants delivered the vaccine three times a week over three weeks during one menstrual cycle, and were followed up for two further months. There were no serious adverse events, and the vaccine was well tolerated. No sustained systemic or local IgG, IgA, or T cell responses to the gp140 were detected following vaginal immunisations. Repeated vaginal immunisation with a HIV-1 envelope protein alone formulated in Carbopol gel was safe, but did not induce local or systemic immune responses in healthy women. TRIAL REGISTRATION: ClinicalTrials.gov NCT00637962.  相似文献   
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103.
Indoleamine 2,3-dioxygenase 1 (IDO1) plays a vital role in tumor immune escape and has emerged as a promising target for cancer immunotherapy. In this study, a novel series of 2,5-dimethylfuran-3-carboxylic acid derivatives were designed, synthesized and evaluated for inhibitory activities against IDO1, and their structure-activity relationship was investigated. Among these, compound 19a exhibited excellent IDO1 inhibitory activity (HeLa cellular IC50?=?4.0?nM, THP-1 cellular IC50?=?4.6?nM). Further molecular docking studies revealed that the compound 19a formed a coordinate bond with the heme iron through the carboxylic acid moiety. These results indicate that compound 19a is a potential IDO1 inhibitor for further investigation.  相似文献   
104.
Seawater reverse osmosis (SWRO) membrane biofouling remains a common challenge in the desalination industry, but the marine bacterial community that causes membrane fouling is poorly understood. Microbial communities at different stages of treatment processes (intake, cartridge filtration, and SWRO) of a desalination pilot plant were examined by both culture-based and culture-independent approaches. Bacterial isolates were identified to match the genera Shewanella, Alteromonas, Vibrio, and Cellulophaga based on 16S rRNA gene sequencing analysis. The 16S rRNA gene clone library of the SWRO membrane biofilm showed that a filamentous bacterium, Leucothrix mucor, which belongs to the gammaproteobacteria, accounted for nearly 30% of the clone library, while the rest of the microorganisms (61.2% of the total clones) were related to the alphaproteobacteria. 16S rRNA gene terminal restriction fragment length polymorphism (T-RFLP) analysis indicated that bacteria colonizing the SWRO membrane represented a subportion of microbes in the source seawater; however, they were quite different from those colonizing the cartridge filter. The examination of five SWRO membranes from desalination plants located in different parts of the world showed that although the bacterial communities from the membranes were not identical to each other, some dominant bacteria were commonly observed. In contrast, bacterial communities in source seawater were significantly different based on location and season. Microbial profiles from 14 cartridge filters collected from different plants also revealed spatial trends.  相似文献   
105.
Ovarian cancer is a highly lethal disease with poor prognosis and especially in high-grade tumor. Emerging evidence has reported that aberrant upregulation and activation of GRB7, ERK as well as FOXM1 are closely associated with aggresivenesss of human cancers. However, the interplay between these factors in the pathogenesis of human cancers still remains unclear. In this study, we found that GRB7 (P<0.0001), ERK phosphorylation (P<0.0001) and FOXM1 (P = 0.001) were frequently increased and associated with high-grade tumors, as well as a high tendency in association with advanced stage ovarian cancer by immunohistochemical analysis. Intriguingly, the expressions of GRB7 (P<0.0001), ERK phosphorylation (P<0.001) and FOXM1 (P<0.001) showed a significant stepwise increase pattern along Grade 1 to Grade 3 ovarian cancers. Biochemical studies using western blot analysis demonstrated that enforced expression or knockdown of GRB7 showed GRB7 could elevate the levels of ERK phosphorylation and FOXM1, whereas enforced expression of FOXM1 could not alter levels of GRB7 and ERK phosphorylation. But inhibition of ERK signaling by U0126 or PD98059 could reduce the level of FOXM1 in GRB7-overexpressing ovarian cancer cells, suggesting that GRB7, ERK and FOXM1 are regulated orderly. Moreover, inhibition of ERK activity by U0126 or PD98059, or decreased FOXM1 expression by Thiostrepton significantly inhibited cell migration/invasion, tumor growth in vitro and in vivo. Collectively, our findings confer that targeting GRB7/ERK/FOXM1 signaling cascade may be a promising molecular therapeutic choice in combating ovarian cancer.  相似文献   
106.
Angiopoietin-like protein 4 (Angptl4) is the second member of the angiopoietin-like family of proteins previously shown to increase plasma triglyceride (TG) levels in vivo. We recently reported that Angptl4 is a variable-sized oligomer formed by intermolecular disulfide bonds and undergoes regulated proteolytic processing upon secretion. We now show that adenoviral overexpression of Angptl4 potently increases plasma TG levels by a mechanism independent of food intake or hepatic VLDL secretion. We determined that cysteine residues at positions 76 and 80 of Angptl4, conserved among mouse, rat, and human, are required to form higher order structures. By generating adenoviral expression vectors of Angptl4 containing different epitope tags at both N and C termini, we show that loss of oligomerization results in decreased stability of the N-terminal coiled-coil domain of Angptl4 as well as decreased ability to increase plasma TG levels, suggesting that intermolecular disulfide bond formation plays important roles in determining the magnitude of the hyperlipidemic effect of Angptl4. Because Angptl4 is more potent than Angptl3 in increasing plasma TG levels in mice, inappropriate oligomerization of Angptl4 could be associated with disorders of lipid metabolism in vivo.  相似文献   
107.
<正> 本文报道以pAT153质粒为载体克隆的adr亚型乙型肝炎病毒(HBV)全基因的限制性内切酶图谱。重组质粒已命名为pHBV-NCl。重组质粒的提取和酶解采用常规方法。限制性内切酶为Bio-Labs公司产品。用Sepharcry S-1000纯化得到的质粒,经电泳鉴定都是完整的超螺旋DNA。经过鉴定其BamHⅠ、XhoⅠ、XbaⅠ、SstⅡ、SphⅠ、BglⅠ、BglⅡ、BstEⅡ、AceⅠ、AvaⅠ、HincⅡ、HpaⅠ等12种酶的21个切口已被定位。其中XhoⅠ、XbaⅠ、SstⅡ、  相似文献   
108.
传染性法氏囊病病毒cDNA文库的构建   总被引:2,自引:0,他引:2  
陈士友  张兹钧 《病毒学报》1994,10(2):159-163
  相似文献   
109.
110.

Objectives

The aim of this study was to understand the effect of substrate stiffness (a mechanical factor of the extracellular matrix) on periodontal ligament stem cells (PDLSCs) and its underlying mechanism.

Materials and methods

Elastic substrates were fabricated by mixing 2 components, a base and curing agent in proportions of 10:1, 20:1, 30:1 or 40:1. PDLSC morphology was observed using scanning electron microscopy (SEM). Cell proliferation and differentiation were assessed after PDLSCs was cultured on various elastic substrates. Data were analysed using one‐way ANOVA.

Results

SEM revealed variations in the morphology of PDLSCs cultured on elastic substrates. PDLSC proliferation increased with substrate stiffness (P < .05). Osteogenic differentiation of PDLSCs was higher on stiff substrates. Notch pathway markers were up‐regulated in PDLSCs cultured on stiff substrates.

Conclusions

Results suggested that the osteogenic differentiation of PDLSCs might be promoted by culturing them in a stiffness‐dependent manner, which regulates the Notch pathway. This might provide a new method of enhancing osteogenesis in PDLSCs.
  相似文献   
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