中药降香的本草考证

降香为我国传统中药材,历代本草对其记载较为混杂,至今基原仍存在较大争议。从名称、基原、产地、品质评价、采收加工及炮制方面进行考证可知,降香本名降真香,历代本草中多以降真香为正名记载,自明代《本草纲目》将降香作为降真香的简称,后至清末、民国时期逐渐以降香作为药材正名。从古至今降香基原历经变革,古代（1840年前）国产降香基原考证为黄檀属藤黄檀Dalbergia hancei Benth.、斜叶黄檀D. pinnata （Lour.） Prain、两粤黄檀D. benthamii Prain、滇黔黄檀D. yunnanensis Franch.等能够产生香材的藤本植物,进口降香基原则考证为黄檀属印度黄檀D. sissoo DC.、小花黄檀D. parviflora Roxb.等具有心材的木本植物;由于降真香（山油柑）Acronychia pedunculata （L.） Miq.植物名与药材名相同,1840—1948年部分著作误将山油柑作降香记载;《中华人民共和国药典》1977年版首次收录降香,规定其基原为降香檀D. odorifera T. Chen。据记载,古代国产和进口降香均无明确道地产区;1949年至今,唯一道地产区为海南省。历代本草记载,进口降香以颜色红且香气甜而不辣,或颜色紫而油润者入药为佳;中华人民共和国成立后,以降香檀心材替代进口降香入药,其品质以颜色紫红、质地坚硬油润者为佳。历代本草记载降香炮制方法包括将其刮下碾成细末和烧存性;近现代以加工成细粉或镑片为主。考证结果为今后成方制剂开发及临床应用提供重要参考。     

中药白芷的基原植物研究Ⅳ.白芷的基原植物、栽培历史以及其近缘野生植物演化的讨论

目的 :确认中药白芷的基原植物 ,探讨其栽培历史变化以及有关近缘野生植物的演化。方法 :对已取得的各项研究结果作综合分析 ,并结合历史文献、分布现状等进行讨论。结果 :各项研究结果与历史文献、分布现状等均较为一致。结论 :①中药白芷的基原植物应是台湾白芷。②建议将雾灵当归处理为兴安白芷的变种 ,定名为A .dahuricavar.porphyrocaulis。③对川 (杭 )白芷和祁 (禹 )白芷不应作分类学上的区分。同时 ,还对中药白芷的使用栽培历史和白芷的野生近缘植物兴安白芷、台湾白芷和雾灵当归的演化关系作出了推断。     

药用亲缘学论纲——知识谱系,认识论和范式转换

中药资源是我国中医药事业发展的基础,采用创新的理论和方法寻找和发现中药新资源是中药资源可持续利用研究的热点和重点。药用亲缘学研究药用生物(特别是药用植物)的生物亲缘关系,化学成分和疗效(传统疗效和药理活性)间的相关性,该学科的建立对于开发中药植物资源具有重要指导意义;系统发育基因组学方法可用于药物发现和开发的相关问题研究,在组学水平拓展了药用亲缘学的领域,由此衍生出药用基因组亲缘学的新概念。该文简述药用亲缘学的知识谱系,研究方法和范式转换,凸显药用基因组亲缘学的理论和实践价值,建议选择《中国药典》2010年版收录最多的毛茛科为例,对药用基因组亲缘学进行深入的实证研究。在基因组,转录组和代谢组水平探讨毛茛科及其重要族属系统发育和进化关系,揭示药用植物基因型和代谢表型,以及近缘种遗传多样性和化学多样性的内在关联。通过毛茛科示范研究,丰富药用亲缘学研究的内涵,扩展其外延,将药用基因组亲缘学视为药用亲缘学的升级版,开放地吸收有关领域的新知识和新技术,促进中药资源学科的成长,推动中药植物资源的开发和可持续利用。     

Xenohormesis:从进化与生态角度理解中药的生物效应

Xenohormesis解释了为何植物受环境胁迫后产生的次生代谢产物能提高取食动物的胁迫耐受性与生存机会,认为在自然选择压力下动物保留着感知这些胁迫信号分子的能力,从而激活进化保守性的细胞应激响应机制,提高逆境适应力.该文在介绍Xenohormesis效应概念与机制,分析总结植物与昆虫及人类的Xenohormesis效应关系的基础上,以人参为例阐述了中药Xenohormesis效应,认为借鉴Xenohormesis理论能从进化与生态角度理解中药生物效应的本质,对中药现代化研究具重要价值.     

Numerical Analysis of Microcrack Propagation Characteristics and Influencing Factors of Serrated Structural Plane

The serrated structural plane is the basic unit of structural plane morphology. However, the understanding of its internal stress distribution, failure mode and crack evolution law was not clear enough in previous studies. In this paper, the shear mechanical properties of the serrated structural planes were studied by numerical simulation, and the crack evolution law of the serrated structural planes and the effects of four microscopic parameters on the shear properties were analyzed. The results show that: (1) the number of microcracks increases with the increase in normal stress; the crack expansion rate is slow before the shear stress reaches the peak. After the shear stress reaches the peak, the crack expansion rate continues to increase, and the microcracks keep sprouting and expanding, and the number of microcracks tends to stabilize when the shear stress reaches the residual shear strength. (2) The particle contact stiffness ratio kn∗/ks∗ and parallel bond stiffness ratio kn/ks were negatively correlated with the shear strength; and the particle contact modulus E and parallel bond modulus E∗ were positively correlated with the shear strength. As the particle contact modulus E and parallel bond modulus E∗ increase, the peak shear displacement gradually decreases. The parallel bond stiffness ratio kn/ks has a negative correlation with the peak shear displacement. This study is expected to provide theoretical guidance for the microscopic parameter calibration and shear mechanical analysis of serrated structural planes. (3) Several XGBoost, WOA-XGBoost, and PSO-XGBoost algorithms are introduced to construct the quantitative prediction model, and the comparative analysis found that WOA-XGBoost has the best fitting effect and can be used for the prediction of shear strength. When using this model to calculate the weight shares of micro-parameters, it was found that kn∗/ks∗ has the greatest influence on shear strength, followed by E∗; E and kn/ks had the least influence.     

Influence of Structural Porosity and Martensite Evolution on Mechanical Characteristics of Nitinol via In-Silico Finite Element Approach

Nitinol (NiTi) alloys are gaining extensive attention due to their excellent mechanical, superelasticity, and biocompatibility properties. It is difficult to model the complex mechanical behavior of NiTi alloys due to the solid-state diffusionless phase transformations, and the differing elasticity and plasticity presenting from these two phases. In this work, an Auricchio finite element (FE) model was used to model the mechanical behavior of superelastic NiTi and was validated with experimental data from literature. A Representative Volume Element (RVE) was used to simulate the NiTi microstructure, and a microscale study was performed to understand how the evolution of martensite phase from austenite affects the response of the material upon loading. Laser Powder Bed Fusion (L-PBF) is an effective way to build complex NiTi components. Porosity being one of the major defects in Laser Powder Bed Fusion (L-PBF) processes, the model was used to correlate the macroscale effect of porosity (1.4–83.4%) with structural stiffness, dissipated energy during phase transformations, and damping properties. The results collectively summarize the effectiveness of the Auricchio model and show that this model can aid engineers to plan NiTi processing and operational parameters, for example for heat pump, medical implant, actuator, and shock absorption applications.     

从生物进化看脑苷脂类化合物的分布及其生物活性研究进展

脑苷脂类化合物是一类广泛存在于菌类、植物类、动物类及海洋生物组织细胞膜中含量很低的内源性生物活性物质。本文就近年来发现的脑苷脂类化合物的化学结构特点与生物进化相关性、脑苷脂类的生物合成与体内转化、生物活性与药理作用、应用前景等方面的研究进行综述和展望,为此类活性成分的深入研究提供参考。     

登革1型病毒广州2006年分离株的基因组特征与进化分析

目的 对2006年分离自广州登革热患者血清的4株登革1型病毒(GZ57/06、GZ63/06、GZ69/06和GZ128/06)进行全基因组序列测定,并同其他毒株序列进行比对分析,以了解其基因组序列特征及可能的传播来源.方法 将登革1型病毒分离株基因组分为9个片段进行RT-PCR扩增,5'与3'末端序列采用RACE法扩增,扩增产物纯化后进行PCR测序.通过末端重叠序列拼接成全长病毒基因组序列,利用生物信息学软件对序列进行比对分析.结果 测序获得的4株广州登革1型病毒基因组全长均为10 735核苷酸(m),编码3 393个氨基酸.5'和3'端各有一段非编码区,长度分别为94nt和462nt.4株病毒的编码区与非编码区核苷酸及氨基酸序列存在一些差异,其中GZ57/06、GZ63/06和GZ69/06毒株的基因组核苷酸和氨基酸序列同源性均在99%以上,而GZ128/06株变异较其他3株大,编码区差异尤其明显.序列比对分析表明,GZ57/06、GZ63/06和GZ69/06毒株均与泰国2001年分离毒株ThD1/0049/01和ThD1/0102/01同源性最高,而GZ128/06毒株与缅甸1998年分离毒株D1.Myanrmr.31987/98同源性最高.这些新分离毒株与东南亚毒株属于同一基因型.结论 新分离毒株可能来自泰国等东南亚国家和地区,不同毒株表型差异可能与其基因组特征具有密切关系.     

Highly Divergent SARS-CoV-2 Alpha Variant in Chronically Infected Immunocompromised Person

We detected a highly divergent SARS-CoV-2 Alpha variant in an immunocompromised person several months after the latest detection of the Alpha variant in the Netherlands. The patient was infected for 42 weeks despite several treatment regimens and disappearance of most clinical symptoms. We identified several potential immune escape mutations in the spike protein.