Small diameter blood vessels with controllable micropore structure induced by centrifugal force for improved endothelialization

The micropore structure is prerequisite for fast and durable endothelialization of artificial small diameter blood vessels (ASDBVs). Although some methods, such as salt leaching, coagulation, and electrospinning, have been developed to construct micropores for ASDBVs, the uncontrollability of the structure and the complicated procedures of the process are still the issues to be concerned about. In this study, a compact device based on the principle of centrifugal force is established and used to prepare polyurethane (PU) ASDBVs with micropore structures by blasting different porogens. It is found that the glass beads could construct micropores with regular round shape, uniform distribution, and controllable size (60–350 µm), which significantly improves the endothelialization of PU‐based ASDBVs, especially when the pore size is about 60 µm. This method is easy‐accessible and wide‐applicable, which provides a new pathway for the research and development of ASDBVs.     

A Plasmodium homolog of ER tubule-forming proteins is required for parasite virulence

Reticulon and REEP family of proteins stabilize the high curvature of endoplasmic reticulum (ER) tubules. Plasmodium berghei Yop1 (PbYop1) is a REEP5 homolog in Plasmodium. Here, we characterize its function using a gene-knockout (Pbyop1∆). Pbyop1∆ asexual stage parasites display abnormal ER architecture and an enlarged digestive vacuole. The erythrocytic cycle of Pbyop1∆ parasites is severely attenuated and the incidence of experimental cerebral malaria is significantly decreased in Pbyop1∆-infected mice. Pbyop1∆ sporozoites have reduced speed, are slower to invade host cells but give rise to equal numbers of infected HepG2 cells, as WT sporozoites. We propose that PbYOP1’s disruption may lead to defects in trafficking and secretion of a subset of proteins required for parasite development and invasion of erythrocytes. Furthermore, the maintenance of ER morphology in different parasite stages is likely to depend on different proteins.     

中国连香树科的系统研究——Ⅱ.次生木质部的显微和超微结构

本文报道连香树木材解剖和扫描电镜研究结果,连香树木材特征较为原始,具导管和管胞,导管端壁斜、梯状穿孔板、具有超出穿孔板的三生螺旋加厚,管胞为原始的梯纹管胞,木纤维壁上具裂隙状纹孔,木薄壁组织离管型,星散状分布,木射线异型。     

吡啶锰配合物诱导肿瘤细胞死亡的作用及对线粒体功能的影响

研究新合成的小分子吡啶锰配合物Adpa-Mn（III）（[（Adpa）Mn（μ2-O）2Mn（Adpa）]PF6.8H2O（Adpa=bis（2-pyridylmethyl）amino-2-propionic acid））的抗肿瘤作用,初步探索其抗肿瘤的机制。MTT分析Adpa-Mn（III）对细胞活性的影响;活细胞工作站观察GFP荧光标记组蛋白HeLa细胞的细胞核形态,MDC染色以及GFP-LC3质粒转染,探讨细胞死亡的方式;JC-1染色检测线粒体膜电位;Fluo-3-AM和DCFH-DA荧光探针分别检测细胞中Ca^2＋和ROS的含量。结果发现,Adpa-Mn（III）剂量依赖性地抑制细胞活性;给药后细胞核出现固缩、片段化;自噬小泡增多,GFP-LC3荧光强度增强;线粒体膜电位下降;细胞内Ca^2＋发生超载,ROS含量升高。由此,Adpa-Mn（III）可抑制肿瘤细胞活性,其机制与引起线粒体膜电位下降、增加ROS生成及诱导细胞的死亡有关,同时胞内Ca^2＋超载也参与了该作用。这些数据显示,Adpa-Mn（III）具有成为抗肿瘤先导金属配合物的潜在可能性。     

An energy budget approach for evaluating the biocontrol potential of cotton aphid (Aphis gossypii) by the ladybeetle Propylaea japonica

Biological control of economically important crop pests is an important component of integrated pest management (IPM) strategies. Predator–prey energy relationships are critical to the success of biocontrol strategies; however, these relationships are often ignored in many IPM programs. In this study, the biocontrol potential of cotton aphid, Aphis gossypii (Glover) (Hemiptera: Aphididae), by the ladybeetle Propylaea japonica (Thunberg) (Coleoptera: Coccinellidae) was estimated in terms of energy budgets calculated at 27 ± 1 °C. The energy equivalent of prey subjects (aphids) consumed was estimated from bomb calorimetry and partitioned into the energy associated with ingestion, assimilation, respiration, reproduction, and waste for each developmental stage of the lady beetle. The average assimilation efficiencies for larval and adult ladybeetles were 88.2 and 91.1%, respectively, whereas net ecological efficiencies were 17.6% for larvae and 2.6% for adults. Similarly, assimilation efficiencies of cotton aphids were 71.5 and 74.4% for nymphs and adults, respectively. Based on energy budget calculations, approximately 520, 3‐day‐old aphids and 5 356, 3‐day‐old aphids were estimated to be consumed by the ladybeetle larval stage and the female adult stage, respectively. These estimates were similar to the actual number of aphids consumed by the ladybeetles, based on actual counts. The current data demonstrate that P. japonica is an important natural enemy of the cotton aphid, and that predator–prey energy relationships can play a critical role in biocontrol strategies and IPM programs.     

Molecular cloning and characterization of an inducible RNA-dependent RNA polymerase gene, <Emphasis Type="Italic">GhRdRP</Emphasis>, from cotton (<Emphasis Type="Italic">Gossypium hirsutum</Emphasis> L.)

The RNA-dependent RNA polymerase (RdRP) cDNA, designated as Gossypium hirsutum RdRP (GhRdRP) was cloned from cotton by rapid amplification of cDNA ends-polymerase chain reaction (RACE-PCR). The full-length cDNA was 3,672 bp in size and encoded an open reading frame (ORF) of 1,110 amino acids which contained the RdRP conserved functional domain and the signature motif DbDGD. Amino acid sequence alignment indicated that GhRdRP shared the highest identity (66.37%) with AtRdRP1 and had homology with other plant, fungal, yeast and nematode RdRPs. The corresponding genomic DNA containing five exons and four introns, was isolated and analyzed. Also a 5′-flanking region was cloned, and a group of putative cis-acting elements were identified. Southern blot analysis revealed a single copy of the GhRdRP gene in cotton genome. The expression analysis by semi-quantitative RT-PCR showed that GhRdRP was induced by salicylic acid (SA), 5-chloroSA (5-CSA) and fungal infection of Rhizoctonia solani Kuhn. The cloning and characterization of the GhRdRP gene will be useful for further studies of biological roles of GhRdRP in plants.     

胡杨、灰叶胡杨果实空间分布及其数量特性的研究

胡杨、灰叶胡杨种间比较,果穗、种子在树冠上的垂直分布均表现为树冠上层最多,中层居中,下层最少,树冠南北侧相比较,南侧果穗量多于北侧.单果种子量在树冠各层次上差异不显著.胡杨单果重是灰叶胡杨的2.68倍,千粒重是灰叶胡杨的1.33倍,单果种子量是灰叶胡杨的2.14倍,单株种子量是灰叶胡杨的1.28倍,而单株果实量灰叶胡杨是胡杨的1.59倍.同一个种不同居群间比较,胡杨、灰叶胡杨均是单株果穗数和果穗果实数各居群间都存在差异,胡杨各居群间单果重、单果种子量差异不显著,而灰叶胡杨各居群间单果重及单果种子量差异极显著.表明胡杨在物质和能量上对后代的投资能力强于灰叶胡杨,生殖策略是通过较高的单果种子量来保证一定数量的单株种子量;而灰叶胡杨单果种子量较低,却是通过较高的单株果量来保证单株种子量,并且较小的种子占据空间生态位的潜能较胡杨占优势.     

山羊胚胎干细胞的分离与培养

对关中奶山羊配种后6～7天的桑椹胚和囊胚,分别采用全胚培养法、酶消化法和免疫外科法进行处理.将处理后的胚胎培养于小鼠胎儿成纤维细胞(MEF)饲养层上,分离培养山羊胚胎干细胞(Embryonic stem cell,ESC).对分离传代的山羊ESCs分别进行免疫组化染色,RT-PCR检测和体外诱导分化试验.结果表明.全胚培养法易于胚胎贴壁形成原代集落,采用全胚培养法获得的ESCs有一株目前已传至18代.山羊ESCs Nanong、Oct4、SSEA-3免疫组化染色呈阳性,SSEA-1免疫组化染色呈弱阳性,SSEA-4免疫组化染色呈阴性,RT-PCR检测显示其表达Nanog、Oct4、端粒酶、CD117.山羊ESCs经DMSO体外诱导可以向心肌细胞分化.这些试验均表明该细胞具有ESCs的生物学特性.     

黑曲霉脯氨酸蛋白内肽酶基因的克隆与序列分析

以黑曲霉(A.niger)TCCC41013的总RNA作为模板,通过RT-PCR扩增出含自身信号肽的脯氨酸蛋白内肽酶基因,将其插入pUCm-T载体上,经PCR和酶切鉴定后进行测序并分析.所克隆的PEP基因全长为1 581bp,编码526个氨基酸残基,成熟肽为504个氨基酸残基.与GeneBank中已报道的A.niger CBS513.88的PEP序列同源性最高,达到99.75%.脯氨酸蛋白内肽酶是一种新型的丝氨酸蛋白酶,黑曲霉PEP与已克隆的其他菌种的PEP同源性不高.