New era for mucosal mast cells: their roles in inflammation,allergic immune responses and adjuvant development

To achieve immune homeostasis in such a harsh environment as the intestinal mucosa, both active and quiescent immunity operate simultaneously. Disruption of gut immune homeostasis leads to the development of intestinal immune diseases such as colitis and food allergies. Among various intestinal innate immune cells, mast cells (MCs) play critical roles in protective immunity against pathogenic microorganisms, especially at mucosal sites. This suggests the potential for a novel MC-targeting type of vaccine adjuvant. Dysregulated activation of MCs also results in inflammatory responses in mucosal compartments. The regulation of this yin and yang function of MCs remains to be elucidated. In this review, we focus on the roles of mucosal MCs in the regulation of intestinal allergic reaction, inflammation and their potential as a new target for the development of mucosal adjuvants.     

Non-isothermal crystallization kinetics and morphology of wollastonite-filled β-isotactic polypropylene composites

To obtain wollastonite-filled β-iPP composites, the wollastonite with β-nucleating surface (β-wollastonite) was prepared through chemical reaction between wollastonite with α-nucleating surface (α-wollastonite) and pimelic acid. The formation of calcium pimelate on the surface of wollastonite was proved using Fourier transform infrared spectrometry and scanning electron microscopy. The crystallization behavior, melting characteristics, non-isothermal crystallization kinetics, and crystalline morphologies of α- and β-wollastonite-filled iPP composites were studied by differential scanning calorimetry and polarizing optical microscopy. It is found that the crystallization peak temperatures of β-wollastonite-filled iPP composites were higher than that of α-wollastonite-filled iPP composites, which indicated that wollastonite with β-nucleating surface has stronger heterogeneous nucleation than that of wollastonite with α-nucleating surface. Although the crystallization temperatures of iPP and iPP composites decreased with increasing cooling rates, α-wollastonite-filled iPP composites mainly crystallized in α-spherulite and β-wollastonite-filled iPP composites formed β-spherulite. In addition, the spherulite size of β-wollastonite-filled iPP composites was smaller than that of α-wollastonite-filled iPP composites. Jeziorny and Mo methods were applicable to study the non-isothermal crystallization kinetics of wollastonite-filled iPP composites. The activation energy (?E) and the nucleation efficiency (EN) of non-isothermal crystallization were calculated by Kissinger method and the equation proposed by Fillon, respectively. The β-wollastonite-filled iPP composites exhibited higher crystallization rate, activation energy, and EN than that of α-wollastonite-filled iPP composites.     

β-PbO2/TiO2纳米管电极的制备及其电催化降解苯酚

采用阳极氧化法和脉冲电沉积制备出β-PbO2改性TiO2纳米管(β-PbO2/TiO2-NTs)电极,通过扫描电子显微镜(SEM)、X射线衍射(XRD)和X射线光电子能谱(XPS)等技术手段对制备的β-PbO2/TiO2-NTs电极的表面形貌和结构进行了表征。结果表明,该方法成功地将β-PbO2纳米颗粒分散在TiO2纳米管中,通过电催化降解苯酚评价了β-PbO2/TiO2-NTs电极的电催化活性,实验结果表明,在TiO2-NTs中电沉积β-PbO2提高了电极的电催化活性,对苯酚的降解达到83%。     

Self‐Replication and Amplification of Enantiomeric Excess of Chiral Multifunctionalized Large Molecules by Asymmetric Autocatalysis

Self‐replication of large chiral molecular architectures is one of the great challenges and interests in synthetic, systems, and prebiotic chemistry. Described herein is a new chemical system in which large chiral multifunctionalized molecules possess asymmetric autocatalytic self‐replicating and self‐improving abilities, that is, improvement of their enantioenrichment in addition to the diastereomeric ratio. The large chiral multifunctionalized molecules catalyze the production of themselves with the same structure, including the chirality of newly formed asymmetric carbon atoms, in the reaction of the corresponding achiral aldehydes and reagent. The chirality of the large multifunctionalized molecules controlled the enantioselectivity of the reaction in a highly selective manner to construct multiple asymmetric stereogenic centers in a single reaction.     

Water-Insensitive Synthesis of Poly-β-Peptides with Defined Architecture

Biocompatible and proteolysis-resistant poly-β-peptides have broad applications and are dominantly synthesized via the harsh and water-sensitive ring-opening polymerization of β-lactams in a glovebox or using a Schlenk line, catalyzed by the strong base LiN(SiMe₃)₂. We have developed a controllable and water-insensitive ring-opening polymerization of β-amino acid N-thiocarboxyanhydrides (β-NTAs) that can be operated in open vessels to prepare poly-β-peptides in high yields, with diverse functional groups, variable chain length, narrow dispersity and defined architecture. These merits imply wide applications of β-NTA polymerization and resulting poly-β-peptides, which is validated by the finding of a HDP-mimicking poly-β-peptide with potent antimicrobial activities. The living β-NTA polymerization enables the controllable synthesis of random, block copolymers and easy tuning of both terminal groups of polypeptides, which facilitated the unravelling of the antibacterial mechanism using the fluorophore-labelled poly-β-peptide.     

Degradation of Structurally Defined Graphene Nanoribbons by Myeloperoxidase and the Photo-Fenton Reaction

As an emerging member of the graphene family, structurally defined graphene nanoribbons (GNRs) have shown promising applications in various fields. The evaluation of the degradability of GNRs is particularly important for assessing the persistence level and risk of these materials in living organisms and the environment. However, there is a void in the study of the degradation of GNRs. Here, we report the degradation behavior of GNRs in the presence of human myeloperoxidase (hMPO) or treated with the photo-Fenton (PF) reaction. With the assistance of potassium hydroxide or imidazole, which facilitates the dispersion of GNRs in the aqueous solution, GNRs underwent only partial degradation after 25-hour incubation with hMPO, while, the PF reaction degraded GNRs almost completely after 120 hours. These results indicate that structurally precise GNRs can be efficiently degraded under suitable conditions, providing more opportunities for future applications in different fields.     

人肝癌细胞系HLE细胞表面抗原多肽的纳升电喷雾串联质谱从头测序分析

肿瘤细胞表面的抗原多肽能够被细胞毒T淋巴细胞特异性识别而引起免疫应答,因此有可能用于研制基于多肽的抗肿瘤疫苗。用弱酸将人肝癌细胞系HLE细胞表面抗原多肽和人正常肝细胞表面多肽洗脱后,经RP-HPLC分离,选择HLE细胞表面特异性多肽进行纳升电喷雾串联质谱(nanoESI-MS/MS)测序,共测定5个色谱峰中的20个多肽序列,分子量分布范围为1000~2000 Da。借助M asSeq软件分析出其中12个多肽的序列。经数据库查寻,其中的3个肽段分别来自钙调节蛋白、核蛋白S19和伴侣蛋白10。这些多肽的生物学功能及与肿瘤的关系值得深入研究。该研究表明nanoESI-MS/MS是测定微量混合多肽序列的最有效方法。     

PBDEs研究的最新进展

多澳联苯醚(PBDEs)是一类环境中广泛存在的全球性有机污染物.由于其具有环境持久性、远距离传输、生物可累积性及对生物和人体具有毒害效应等特性,对其环境问题的研究已成为当前环境科学的一大热点.本文对最近几年来环境中PBDEs研究的进展进行综述,对多溴联苯醚在环境及生物体中的分布、时间趋势、人体暴露及途径、环境中的降解和生物代谢以及生物累积与生物放大方面的研究进行了总结,对目前存在问题及进一步的研究方向进行了讨论和展望.     

Hierarchical nanowires for high-performance electrochemical energy storage

Nanowires are promising candidates for energy storage devices such as lithium-ion batteries, su- per（：apa.citors and lithium-air batteries. However, simple-structured nanowires have some limitations hence the strategies to make improvements need to be explored and investigated. Hierarchical nanowires with enhanced periormanee have been considered as an ideal candidate for energy storage due to the novel structures and/or synergistic properties. This review describes some of the recent progresses in the hierarchical nanowire merits, classification, synthesis and performance in energy storage applieat, ions. Herein we discuss the hierarchical nanowires based on their structural design from three major categories, including exterior design, interior design and aligned nanowire assembly. This review also briefly outlines the prospects of hierarchical nanowires in morphology control, property enhancement and application versatility.     

Multi-separation, centrifugality and centripetality imply chaos

Let be an interval. need not be compact or bounded. Let be a continuous map, and be a trajectory of with or . Then there is a point such that . A point is called a centripetal point of relative to if or , and is centrifugal if or . In this paper we prove that if there exist centripetal points of in , then has periodic points of some odd () period . In addition, we also prove that if ) is multi-separated by Fix(), or there exists a centrifugal point of in , then is turbulent and hence has periodic points of all periods.