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11.
Accurate and efficient antigen delivery is crucial for inducing a strong and long-term immune response. A visible protein nanovaccine made from antigen could provide a novel and promising technology for secure and efficient delivery of the antigen with imaging visualization. In this study, a functional nanovaccine based on genipin crosslinked ovalbumin (OVA) fluorescent nanoparticles with chitosan (CS-OVA-NPs) was developed. The nanovaccine can carry abundant antigens by self-crosslinking without additional carriers. The fluorescence imaging technique was applied to monitor and reveal the process of antigen delivery in vivo based on the fluorescence of genipin with a non-invasive and real-time manner. This functional OVA nanovaccine can enhance the uptake of OVA in Dendritic Cells (DCs) and further promote DCs to maturate in vitro. In vivo study further indicated CS-OVA-NPs could trigger antigen-specific immune responses, which demonstrated that this fluorescent nanovaccine provided a novel design approach for accurate and efficient vaccine delivery.  相似文献   
12.
Cancer metastasis is one of the biggest challenges in cancer treatments since it increases the likelihood that a patient will die from the disease. Therefore, the availability of techniques for the early detection and quantification of tumors is very important. We have prepared cyanine 7.5 NHS ester (Cy7.5) and folic acid (FA) conjugated biodegradable mesoporous silica nanoparticles (bMSN@Cy7.5-FA NPs) (~100 nm) for visualizing tumors in vivo. The fluorescence spectra revealed that the emission peak of bMSN@Cy7.5-FA NPs had a red-shift of 1 nm. Confocal immunofluorescent images showed that bMSN@Cy7.5-FA NPs had an excellent targeting ability for visualizing cancer cells. In vivo fluorescence imaging has been conducted using an orthotopic model for pancreatic cancer within 48 h, and the fluorescence intensity reached a maximum at a post injection time-point of 12 h, which demonstrated that the use of bMSN@Cy7.5-FA NPs provides an excellent imaging platform for tumor precision therapy in mice.  相似文献   
13.
Parkinson’s disease (PD) is second most common neurodegenerative disorder worldwide. Although drugs and surgery can relieve the symptoms of PD, these therapies are incapable of fundamentally treating the disease. For PD patients, over-expression of α-synuclein (SNCA) leads to the death of dopaminergic neurons. This process can be prevented by suppressing SNCA over-expression through RNA interference. Here, we successfully synthesized gold nanoparticles (GNP) composites (CTS@GNP-pDNA-NGF) via the combination of electrostatic adsorption and photochemical immobilization, which could load plasmid DNA (pDNA) and target specific cell types. GNP was transfected into cells via endocytosis to inhibiting the apoptosis of PC12 cells and dopaminergic neurons. Simultaneously, GNP composites are also used in PD models in vivo, and it can successfully cross the blood-brain barrier by contents of GNP in the mice brain. In general, all the works demonstrated that GNP composites have good therapeutic effects for PD models in vitro and in vivo.  相似文献   
14.
Liu  Yaofu  Li  Huiling  Dong  Jianyi  Ma  Lei  Liao  Aijun  Rong  Zhuona  Zhou  Zhi  Cao  Liang  Wang  Fujin  Wang  Jingyu  Wang  Aiguo 《Clinical and experimental medicine》2019,19(1):121-132
Clinical and Experimental Medicine - Deficiency of γ-glutamyl carboxylation of coagulation factors, as evidenced by the elevated level of Des-γ-carboxyl prothrombin (DCP), is a common...  相似文献   
15.
The objective of this article is to evaluate whether the tumoricidal activity of mouse IFN R−/− nature killer (NK) cells is induced by Newcastle disease virus hemagglutinin-neuraminidase (NDV-HN) stimulation, and to investigate what is the mechanism of the HN-stimulated NK cells to kill mouse hepatoma cell line in vitro. The mouse IFN R−/− NK cells were stimulated for 16 hr with 500 ng/mL NDV-HN in 1640 medium. Quantify the cytotoxic activities of NK cells against mouse hepatoma cells (Hepa1-6) by flow cytometry. Granzymes B (GrB) and Fas/FasL concentrations in the supernatants of IFN R−/− NK cells medium were determined by specific ELISA assay. The expression of cell surface GrB and Fas was determined by Western blot. NDV-HN stimulation enhanced tumoricidal activity of IFN R−/− NK cells toward Hepa1-6 in vitro. Treating with anti-HN neutralizing mAb induced significant decline in the cytotoxicity of IFN R−/− NK cells toward Hepa1-6 cell line (P < 0.05). After treating with anti-HN protein (1 μL/mL), Syk-specific inhibitor Herbimycin A(250 ng/mL) and NF-κB inhibitor PDTC (500 ng/mL) downregulated the tumoricidal activity of HN-stimulated IFN R−/− NK cells (P < 0.05). Moreover, significant suppressions in the production of GrB and Fas/FasL were observed in HN-stimulated IFN R−/− NK cells (P < 0.05). Thus, we concluded that killer activation receptors pathway is involved in the IFN-γ-independent GrB and Fas/FasL expression of NDV-HN-stimulated IFN R−/− NK cells, and these are activated by Syk and NF-κB. Anat Rec, 302:1718–1725, 2019. © 2019 The Authors. The Anatomical Record published by Wiley Periodicals, Inc. on behalf of American Association for Anatomy  相似文献   
16.
The purpose of this study was to examine the mediating and moderating roles of resilience on the relationship between perceived stress and depression among heroin addicts. A total of 138 heroin addicts completed the measures of perceived stress, resilience, and depression. Correlation analysis indicated that perceived stress was positively associated with depression. Resilience was negatively correlated with perceived stress and depression. Mediation analysis revealed that resilience partially mediated the relationship between perceived stress and depression. However, resilience did not moderate the influence of perceived stress on depression. These findings might provide a better understanding of the mental health among heroin addicts.  相似文献   
17.
The Cluster of differentiation 226(CD226)/T cell immunoglobulin and immune receptor tyrosine-based inhibitory motif domain (TIGIT) axis plays an important role in the balance of the immune response. A previous study showed that CD226 is involved in CD4+ T cell differentiation and that blocking CD226 may attenuate experimental autoimmune encephalomyelitis (EAE) development. However, the molecular mechanisms underlying this process remain incompletely understood. In this study, it was found that Cd226−/− mice were less susceptible to EAE and that there was less T helper 17(Th17) cell infiltration with higher levels of regulatory cells (Tregs) infiltration in the Cd226−/− EAE mouse central nervous system (CNS) compared with that in the WT EAE mouse CNS. Moreover, the suppressive function of Cd226−/− Tregs was upregulated compared with that of WT Tregs. Furthermore, it was observed that the expression levels of CTLA-4 and TIGIT on Cd226−/− Tregs were higher than those on WT Tregs during EAE in the spleen and CNS. Our results demonstrate a pivotal role for CD226 in attenuating Treg function in EAE that was associated with downregulating the expression levels of CTLA-4 and TIGIT.  相似文献   
18.
Medical Microbiology and Immunology - Gram-negative bacterium Legionella is able to proliferate intracellularly in mammalian host cells and amoeba, which became known in 1976 since they caused a...  相似文献   
19.
Liang  Xiongyan  Gu  Yufang  Chen  Xueyang  Li  Tuofan  Gao  Yulong  Wang  Xiaomei  Fang  Chun  Fang  Shouguo  Yang  Yuying 《Virus genes》2019,55(5):726-733
Virus Genes - Avian leukosis virus (ALV) caused tremendous economic losses to poultry industry all over the world, especially in China. One natural recombinant ALV strain, designated as HB2015032,...  相似文献   
20.
目的 彩用彩色多普勒超声(CDFI)对单发肾结石患者输尿管软镜碎石术围手术期肾血流动力学的评价。 方法 分析2016年7月至2018年6月共61例输尿管软镜碎石手术的单发肾结石患者,应用CDFI观察围手术期术侧肾叶间动脉血流参数,记录术前1 d、术后1 h内及术后5 d叶间动脉血流参数,并进行统计学分析。 结果 围手术期肾叶间动脉血流参数整体分析,收缩期峰值流速(Vmax)、舒张末期流速(Vmin)及阻力指数(RI)数值差异分别具有统计学意义(P<0.05)。与术前血流参数相比,术后1 h叶间动脉Vmax及Vmin均减低,RI增高(P<0.017),术后5 d复查,Vmax及Vmin较术后1 h升高、RI较术后1 h减低(P<0.017),与术前测值相比差异无统计学意义(P>0.017)。 结论 CDFI可以观察并量化输尿管软镜碎石术围手术期肾内动脉灌注,快速评价术侧肾血流动力学变化,手术后会出现短期、可逆性肾叶间动脉流速减低、RI增高。  相似文献   
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