Co-administration of non-carrier nanoparticles boosts antigen immune response without requiring protein conjugation

Nanotechnology promises a revolution in medicine including through new vaccine approaches. The use of nanoparticles in vaccination has, to date, focused on attaching antigen directly to or within nanoparticle structures to enhance antigen uptake by immune cells. Here we question whether antigen incorporation with the nanoparticle is actually necessary to boost vaccine effectiveness. We show that the immunogenicity of a sub-unit protein antigen was significantly boosted by formulation with silica nanoparticles even without specific conjugation of antigen to the nanoparticle. We further show that this effect was observed only for virus-sized nanoparticles (50 nm) but not for larger (1000 nm) particles, demonstrating a pronounced effect of nanoparticle size. This non-attachment approach has potential to radically simplify the development and application of nanoparticle-based formulations, leading to safer and simpler nanoparticle applications in vaccine development.     

涂层修饰的柔性神经电极力学综合性能评估

目的对带有涂层修饰的柔性神经电极进行力学综合性能的评估,为电极及涂层参数的优化设计提供依据。方法对接触、植入以及微动阶段建立简化力学模型,以聚酰亚胺为电极材料,PEG为涂层材料,PDMS模具注塑法为涂层涂覆方法,设置40、80、120、160、200μm涂层厚度梯度,对3个因素(临界载荷、最大形变、脑组织最大应变)进行综合对比评估。结果厚度增加会引起临界载荷增大、最大形变减小以及脑组织最大应变减小,同时也会导致脑组织应变区域增大。均衡3个因素考虑,选择200μm作为涂层最佳厚度,在该厚度下,临界载荷为17.9 m N,最大形变为10.1μm,脑组织最大应变为0.011 4。结论涂层厚度对神经电极的力学性能有较大影响,在具体情况下可通过设置多个力学性能因素的影响因子选择最优参数。涂层的最优参数选择可提高电极的性能,对神经电极的临床应用具有重要意义。     

The molecular mechanism for effects of TiN coating on NiTi alloy on endothelial cell function

The aim of this study is to systematically investigate the molecular mechanism of different effects of nickel titanium (NiTi) alloy surface and titanium nitride (TiN) coating on endothelial cell function. Release of nickel (Ni) ion from bare and TiN-coated NiTi alloys and proliferation of endothelial cells on the two materials were evaluated, and then influence of the two materials on cellular protein expression profiles was investigated by proteomic technology. Subsequently, proteomic data were analyzed with bioinformatics analyses and further validated using a series of biological experiments. Results showed that although the two materials did not affect cell proliferation, the Ni ions released from bare NiTi alloy generated inhibition on pathways associated with actin cytoskeleton, focal adhesion, energy metabolism, inflammation, and amino acid metabolism. In comparison, TiN coating not only effectively prevented release of Ni ions from NiTi alloy, but also promoted actin cytoskeleton and focal adhesion formation, increased energy metabolism, enhanced regulation of inflammation, and promoted amino acid metabolism. Furthermore, the two processes, “the initial mediation of adsorbed serum protein layer to endothelial cell adhesion and growth on the two materials” from our previous study, and “the following action of the two materials on cellular protein expression profile”, were linked up and comprehensively analyzed. It was found that in stage of cell adhesion (within 4 h), release of Ni ions from bare NiTi alloy was very low, and the activation of adsorbed proteins to cell adhesion and growth related biological pathways (such as regulation of actin cytoskeleton, and focal adhesion pathways) was almost as same as TiN-coated NiTi alloy. This indicated that the released Ni ions did not affect the mediation of adsorbed proteins to endothelial cell adhesion. However, in stage of cell growth and proliferation, the release of Ni ions from bare NiTi alloy increased with time and reached a higher level, which inhibited endothelial cell function at molecular level, whereas TiN coating improved endothelial cell function.     

Silica vesicles as nanocarriers and adjuvants for generating both antibody and T-cell mediated immune resposes to Bovine Viral Diarrhoea Virus E2 protein

Bovine Viral Diarrhoea Virus (BVDV) is widely distributed in cattle industries and causes significant economic losses worldwide annually. A limiting factor in the development of subunit vaccines for BVDV is the need to elicit both antibody and T-cell-mediated immunity as well as addressing the toxicity of adjuvants. In this study, we have prepared novel silica vesicles (SV) as the new generation antigen carriers and adjuvants. With small particle size of 50 nm, thin wall (∼6 nm), large cavity (∼40 nm) and large entrance size (5.9 nm for SV-100 and 16 nm for SV-140), the SV showed high loading capacity (∼ 250 μg/mg) and controlled release of codon-optimised E2 (oE2) protein, a major immunogenic determinant of BVDV. The in vivo functionality of the system was validated in mice immunisation trials comparing oE2 plus Quil A (50 μg of oE2 plus 10 μg of Quil A, a conventional adjuvant) to the oE2/SV-140 (50 μg of oE2 adsorbed to 250 μg of SV-140) or oE2/SV-140 together with 10 μg of Quil A. Compared to the oE2 plus Quil A, which generated BVDV specific antibody responses at a titre of 10⁴, the oE2/SV-140 group induced a 10 times higher antibody response. In addition, the cell-mediated response, which is essential to recognise and eliminate the invading pathogens, was also found to be higher [1954-2628 spot forming units (SFU)/million cells] in mice immunised with oE2/SV-140 in comparison to oE2 plus Quil A (512–1369 SFU/million cells). Our study has demonstrated that SV can be used as the next-generation nanocarriers and adjuvants for enhanced veterinary vaccine delivery.     

钛种植体表面新型抗菌涂层预防种植术后早期感染的动物实验研究

目的：通过在犬下颌骨内植入种植体,观察新型抗菌涂层预防种植术后早期感染的实际效果。方法：选择2岁龄牙周健康的雄性Beagle犬4只,拔除双侧下颌第三前磨牙,并在近远中根拔牙窝内预备种植窝行即刻种植术。随机选取2只植入载有新型抗菌涂层的种植体作为实验组,另外2只植入仅微弧氧化处理的种植体作为对照组,并用丝线在所有种植体的颈部结扎,术后给予高糖软食,诱导种植体周围发生早期感染。结扎2个月后对种植体周进行临床指标检查和X线摄片,通过扫描电镜观察种植体／骨组织界面。结果：2个月后,实验组种植体周的临床检查指标明显低于对照组护〈0．05）。X线检查可见：实验组种植体周围无明显的牙槽骨吸收和透射影像,对照组种植体周围可见明显的骨吸收和裂隙状透射影像。扫描电镜观察可见：实验组种植体／骨界面结合较好,未见明显间隙,而对照组种植体与骨组织之间存在明显的间隙。结论：在钛种植体表面构建的新型抗菌涂层具有显著的预防种植术后早期感染的效果。     

Evaluation of surface roughness and bond strength of quartz fiber posts after various pre-treatments

Purpose. Debonding at the post-adhesive interface is a major problem for quartz fiber posts. The objective of this study was to evaluate surface roughness and bond strength of quartz fiber posts after various surface treatments. Materials and methods. Sixty-six quartz fiber posts were randomly divided into six experimental groups (n = 11) including group C, untreated (control); group SB, sandblasted; group SC, silica coated; group HF, hydrofluoric acid-etched; group N, Nd:YAG laser irradiated; group E, Er:YAG laser irradiated. Surface roughness of the posts was measured before and after pre-treatment. They were then bonded to resin cement and tensile bond strength was determined in a universal testing machine. Furthermore, two-way ANOVA and post hoc comparison tests (α = 0.05) were performed on all data. Results. The highest mean force value was observed in group SB and followed by group E. Tukey’s HSD test showed that there was no statistical difference between group SB and group E (p = 0.673). The highest mean roughness value was observed in group SB and a significant difference was found between group SB and all other groups (p < 0.001). This study reveals that sandblasting and Er:YAG laser irradiation provided a significant increase in bond strength between quartz fiber posts and resin cement. Conclusions. Sandblasting or Er:YAG laser-irradiation of the surface of the quartz fiber post before cementation is recommended for increasing retention.     

Cellulose and Its Nano-Derivatives as a Water-Repellent and Fire-Resistant Surface: A Review

The inevitable destructive effects of moisture and temperature are obvious in cellulosic and nanocellulosic substrates. These materials are the main foundations of interdependent industries that produce products such as currency notes or high-quality packaging for sanitary, cosmetics, or ammunition in the defense industry. Therefore, it is essential to develop procedures to eliminate problems arising from humidity and fire to improve the quality of these green and sustainable materials. The production of waterproof and flame-resistant cellulose-based substrates has drawn increasing attention to resolve these drawbacks. In this review paper, we have initially summarized the most accessible cellulosic substrates, different kinds of nanocellulose, and the general information about water repellents and intumescent fireproof surfaces. Then, the potential and necessity of using cellulosic biobased substrates are addressed for use in modified shapes as waterproof and fire inhibitor coatings. Cost-effective, eco-friendly, and durable, dual-function coatings are also introduced as future challenges, which are exploited as water-repellents and flame-retardant cellulose-based surfaces for pulp and paper applications.     

白术黄连微丸结肠靶向胶囊的制备及体外释放研究

目的 将中药"白术黄连方"制备成以胃溶微丸和肠溶微丸为基础的结肠靶向胶囊,优化其处方组成和制备工艺,考察其体外释放特性.方法 采用单因素实验和正交实验法优化微丸的处方组成和工艺参数.用挤出-滚圆技术制备素丸,流化床底喷方式进行包衣,考察隔离衣增重、肠溶衣中聚合物比例、增塑剂用量和包衣增重对肠溶微丸释放行为的影响,并对其...     

Properties of Magnetic Garnet Films for Flexible Magneto-Optical Indicators Fabricated by Spin-Coating Method

Non-destructive testing using a magneto-optical effect is a high-resolution non-destructive inspection technique for a metallic structure. It is able to provide high-spatial resolution images of defects. Previously, it has been difficult to fabricate flexible magneto-optical sensors because thermal treatment is necessary to crystallize the magnetic garnet. Therefore, it was not possible to apply magneto-optical imaging to complicated shapes in a test subject, such as a curved surface. In this study, we developed a new process for deposition of the magnetic garnet on the flexible substrate by applying the magnetic garnet powders that have already undergone crystallization. In this new process, as it does not require thermal treatment after deposition, flexible substrates with low heat resistance can be used. In this paper, we report our observations of the optical properties, magnetic hysteresis loop, crystallizability and density of the particles on the flexible substrate deposited by the spin-coating method.