应用叶表皮结构讨论槽稃草属Euthryptochloa Cope(Gramineae)的归属问题

比较研究单种属,槽稃草属Euthryptochloa Cope与显子草属Phaenosperma Munro的叶表皮微形态,并结合外部形态特征说明槽稃草属与显子草属无论在叶表皮微形态或外部形态上都无区别。根据国际植物命名法规的优先律,槽稃草属不能独立成属,应归入显子草属。     

土壤中质粒pLV1016在快生型大豆根瘤菌间的水平转移

在滤膜、液体培养基和土壤微宇宙 3种系统中 ,研究了接合型质粒 pLV1 0 1 6由快生型大豆根瘤菌 (Rhizobiumfredii)QB1 1 31向R .frediilux3的水平转移及pLV1 0 1 6由QB1 1 31向土著细菌的转移 .接合培养 1d后 ,分别计算供、受体菌的生长速率和质粒转移速率常数 (γ) .结果表明 ,相同接种浓度下 ,滤膜接合时γ值最高 ,土壤中γ值最低 ,γ值不受土壤是否灭菌和是否有大豆植株的影响 ,γ值与初始接种浓度负相关 ,与供、受体的生长速率正相关 .在未灭菌土中检测到 pLV1 0 1 6可转移到土著细菌 ,土著接合子分别属于根瘤菌属和假单胞菌属 .     

银缕梅叶器官的宏观与微观结构及系统意义

银缕梅〔Ｓｈａｎｉｏｄｅｎｄｒｏｎｓｕｂａｅｑｕａｌｅ（Ｃｈａｎｇ）Ｄｅｎｇ,ＷｅｉｅｔＷａｎｇ〕叶表皮毛为星状毛,气孔器为平列式中周缘型,叶缘齿型为弗特吉型,叶肉栅栏组织一层细胞厚,三叶隙三叶迹的节,从茎节到叶之间的维管束呈分离合并分离的变化格局,并且呈续次合并和续次分离发育模式。这些结果进而说明银缕梅属的独立性,也从一个侧面证明它应属于狭义的弗特吉族（Ｆｏｔｈｅｒｇｉｌｅａｅ）。     

放线菌来源活性天然产物发现研究进展

放线菌(Actinomycetes)是抗生素等活性天然产物的重要来源，在临床治疗病原菌感染等重大疾病方面发挥着重要作用。由于抗生素滥用等原因导致临床上出现的以耐甲氧西林金黄色葡萄球菌(methicillin-resistant Staphylococcus aureus, MRSA)等为代表的耐药病菌的种类和数量急剧增加，对人类生存造成了重大威胁。结合现代生物技术进展，加大放线菌来源新抗生素的开发力度刻不容缓。本文对新时期放线菌来源抗生素的发现现状、基于生理操作和基因操作的放线菌来源天然产物挖掘的技术方法等进行综述，以期对放线菌来源活性天然产物的发现提供借鉴。     

Therapeutic applications of adipose-derived stromal vascular fractions in osteoarthritis

Osteoarthritis (OA) is considered to be a highly heterogeneous disease with progressive cartilage loss, subchondral bone remodeling, and low-grade inflammation. It is one of the world's leading causes of disability. Most conventional clinical treatments for OA are palliative drugs, which cannot fundamentally cure this disease. The stromal vascular fraction (SVF) from adipose tissues is a heterogeneous cell population. According to previous studies, it contains a large number of mesenchymal stem cells, which have been used to treat OA with good therapeutic results. This safe, simple, and effective therapy is expected to be applied and promoted in the future. In this paper, the detailed pathogenesis, diagnosis, and current clinical treatments for OA are introduced. Then, clinical studies and the therapeutic mechanism of SVF for the treatment of OA are summarized.     

The histone demethylase Jmjd3 regulates zebrafish myeloid development by promoting spi1 expression

The histone demethylase Jmjd3 plays a critical role in cell lineage specification and differentiation at various stages of development. However, its function during normal myeloid development remains poorly understood. Here, we carried out a systematic in vivo screen of epigenetic factors for their function in hematopoiesis and identified Jmjd3 as a new epigenetic factor that regulates myelopoiesis in zebrafish. We demonstrated that jmjd3 was essential for zebrafish primitive and definitive myelopoiesis, knockdown of jmjd3 suppressed the myeloid commitment and enhanced the erythroid commitment. Only overexpression of spi1 but not the other myeloid regulators rescued the myeloid development in jmjd3 morphants. Furthermore, preliminary mechanistic studies demonstrated that Jmjd3 could directly bind to the spi1 regulatory region to alleviate the repressive H3K27me3 modification and activate spi1 expression. Thus, our studies highlight that Jmjd3 is indispensable for early zebrafish myeloid development by promoting spi1 expression.     

Jabuticaba‐Inspired Hybrid Carbon Filler/Polymer Electrode for Use in Highly Stretchable Aqueous Li‐Ion Batteries

Stretchable electronics are considered as next‐generation devices; however, to realize stretchable electronics, it is first necessary to develop a deformable energy device. Of the various components in energy devices, the fabrication of stretchable current collectors is crucial because they must be mechanically robust and have high electrical conductivity under deformation. In this study, the authors present a conductive polymer composite composed of Jabuticaba‐like hybrid carbon fillers containing carbon nanotubes and carbon black in a simple solution process. The hybrid carbon/polymer (HCP) composite is found to effectively retain its electrical conductivity, even when under high strain of ≈200%. To understand the behavior of conductive fillers in the polymer matrix when under mechanical strain, the authors investigate the microstructure of the composite using an in situ small‐angle X‐ray scattering analysis. The authors observe that the HCP produces efficient electrical pathways for filler interconnections upon stretching. The authors develop a stretchable aqueous rechargeable lithium‐ion battery (ARLB) that utilizes this HCP composite as a stretchable current collector. The ARLB exhibits excellent rate capability (≈90 mA h g^?1 at a rate of 20 C) and outstanding capacity retention of 93% after 500 cycles. Moreover, the stretchable ARLB is able to efficiently deliver power even when under 100% strain.     

Fine Structure of Cardiac Sarcomeres in the Black Widow Spider Latrodectus mactans

Fine structural characteristics of the cardiac muscle and its sarcomere organization in the black widow spider, Latrodectus mactans were examined using transmission electron microscopy. The arrangement of cardiac muscle fibers was quite similar to that of skeletal muscle fibers, but they branched off at the ends and formed multiple connections with adjacent cells. Each cell contained multiple myofibrils and an extensive dyadic sarcotubular system consisting of sarcoplasmic reticulum and T‐tubules. Thin and thick myofilaments were highly organized in regular repetitive arrays and formed contractile sarcomeres. Each repeating band unit of the sarcomere had three apparent striations, but the H‐zone and M‐lines were not prominent. Myofilaments were arranged into distinct sarcomeres defined by adjacent Z‐lines with relatively short lengths of 2.0 μm to 3.3 μm. Cross sections of the A‐band showed hexagon‐like arrangement of thick filaments, but the orbit of thin filaments around each thick filament was different from that seen in other vertebrates. Although each thick filament was surrounded by 12 thin filaments, the filament ratio of thin and thick myofilaments varied from 3:1 to 5:1 because thin filaments were shared by adjacent thick filaments.     

Lipid domains in bacterial membranes

The recent development of specific probes for lipid molecules has led to the discovery of lipid domains in bacterial membranes, that is, of membrane areas differing in lipid composition. A view of the membrane as a patchwork is replacing the assumption of lipid homogeneity inherent in the fluid mosaic model of Singer and Nicolson (Science 1972, 175: 720–731). If thus membranes have complex lipid structure, questions arise about how it is generated and maintained, and what its function might be. How do lipid domains relate to the functionally distinct regions in bacterial cells as they are identified by protein localization techniques? This review assesses the current knowledge on the existence of cardiolipin (CL) and phosphatidylethanolamine (PE) domains in bacterial cell membranes and on the specific cellular localization of certain membrane proteins, which include phospholipid synthases, and discusses possible mechanisms, both chemical and physiological, for the formation of the lipid domains. We propose that bacterial membranes contain a mosaic of microdomains of CL and PE, which are to a significant extent self‐assembled according to their respective intrinsic chemical characteristics. We extend the discussion to the possible relevance of the domains to specific cellular processes, including cell division and sporulation.