Ang II Enhances Noradrenaline Release from Sympathetic Nerve Endings Thus Contributing to the Up-Regulation of Metalloprotease-2 in Aortic Dissection Patients' Aorta Wall

Object

To test the hypothesis that angiotensin II (Ang II) could enhance noradrenaline (NA) release from sympathetic nerve endings of the aorta thus contributing to the up-regulation of matrix metalloproteinase 2 (MMP-2) during the formation of aortic dissection (AD).

Methods

Ang II, NA, MMP-2, MMP-9 of the aorta sample obtained during operation from aortic dissection patients were detected by High Performance Liquid Chromatography and ELISA and compared with controls. Isotope labelling method was used to test the impact of exogenous Ang II and noradrenaline on the NA release and MMP-2, MMP-9 expression on Sprague Dawley (SD) rat aorta rings in vitro. Two kidneys, one clip, models were replicated for further check of that impact in SD rats in vivo.

Results

The concentration of Ang II, MMP-2, 9 was increased and NA concentration was decreased in aorta samples from AD patients. Exogenous Ang II enhanced while exogenous NA restrained NA release from aortic sympathetic endings. The Ang II stimulated NA release and the following MMP-2 up-regulation could be weakened by Losartan and chemical sympathectomy. Beta blocker did not influence NA release but down-regulated MMP-2. Long term in vivo experiments confirmed that Ang II could enhance NA release and up-regulate MMP-2.

Conclusions

AD is initiated by MMP-2 overexpression as a result of increased NA release from sympathetic nervous endings in response to Ang II. This indicates an interaction of RAS and SAS during the formation of AD.     

RBP2 Induces Epithelial-Mesenchymal Transition in Non-Small Cell Lung Cancer

RBP2 has been found to actively participate in cancer progression. It inhibits the senescence of cancer cells, mediates cancer cell proliferation and promotes cancer metastasis. It is also essential to drug tolerance. However, the effects of RBP2 on epithelial-mesenchymal transition are still unknown. In this study, we analyzed the effects of RBP2 on epithelial-mesenchymal transition in non-small cell lung cancer. The results showed that RBP2 down-regulated the expression of E-cadherin by inhibiting the promoter activity of E-cadherin and up-regulated the expression of N-cadherin and snail via the activation of Akt signaling, and the overexpression of RBP2 induced epithelial-mesenchymal transition in non-small cell lung cancer cells. Our study further indicated thatRBP2 may be a potential target for anti-lung cancer therapy.     

Immunoregulation and antioxidant activities of a novel acidic polysaccharide from Radix Paeoniae Alba

Radix Paeoniae Alba is widely used in Chinese traditional medicine to treat various diseases such as gastrointestinal disorders, immunomodulatory, cancer, and other diseases. In this paper, a novel acidic polysaccharide RPAPS purified from Radix Paeoniae Alba was evaluated for its structural features and potential of immunomodulatory and antioxidant activities. RPAPS (molecular weight: 1.0× 105 Da) was mainly composed of α-(1 → 4)-Glcp, α-Arap, α-Galp, α-Rhap, β-D-Glcp, α-(1 → 6)-linked Glcp and GalA. Immunological tests indicated that RPAPS could improve RAW264.7 phagocytic activity and LPS-induced splenocyte proliferation. For antioxidant activities, RPAPS showed reducing power and DPPH scavenging activity in dose dependent. Moreover, RPAPS could significantly protect the PC12 cells from H2O2 damage. These data implied polysaccharides RPAPS had the potential to be novel natural antioxidative and immunopotentiating agents for using in functional foods or medicine.     

STEME系统:一种助力体内定向进化的新工具

通过定向进化(directed evolution)可以快速进行蛋白工程改良及重要基因功能研究,以获得新型农艺性状突变体。近期,中国科学院遗传与发育生物学研究所高彩霞团队和李家洋团队合作构建了新型的饱和靶向内源诱变编辑器(saturated targeted endogenous mutagenesis editors, STEMEs),并在植物中实现了基因的定向进化和功能筛选。该系统融合了现有的2种单碱基编辑技术,成功实现在植物体内同时诱导C:G>T:A、A:T>G:C双碱基编辑,通过靶向OsACC羧基转移酶结构域编码序列定向进化出水稻除草剂抗性植株。这种在体内进行基因定向进化的新方法,对于今后农作物重要农艺性状的筛选和功能基因研究具有重要作用。本文对STEME系统的组成、编辑效率和应用原理进行介绍,并与已有的定向进化方法进行比较,为加速作物种质资源创新研究提供参考。     

铜绿假单胞菌PAO1 ku基因缺失菌株的构建及其对生物被膜耐药性的影响

【背景】铜绿假单胞菌是常见的条件致病菌,易形成生物被膜,具有基因突变率高、耐药性强的特点。非同源末端连接是DNA双链断裂的主要修复途径之一,修复过程会导致DNA突变产生。【目的】研究非同源末端连接对生物被膜中的铜绿假单胞菌基因突变率和耐药性的影响。【方法】通过基因无痕敲除的方法构建PAO1菌株的ku基因缺失突变株Δku并构建其回补株。对比研究突变株和野生菌株生物被膜形成能力、生物被膜状态下各菌的基因突变率以及对抗生素的耐受性。通过荧光定量PCR检测生物被膜中PAO1菌株ku基因的表达水平。【结果】各突变株生物被膜形成能力无显著差异;与野生菌株相比,突变株Δku在生物被膜中的基因突变率以及对环丙沙星和庆大霉素的最低抑菌浓度(minimum inhibitory concentration,MIC)下降。荧光定量PCR结果表明,ku基因在生物被膜形成早期转录水平有明显上调。【结论】非同源末端连接修复途径对生物被膜中的铜绿假单胞菌基因突变率以及耐药性的提高有一定的作用。本研究将为后续进一步阐释铜绿假单胞菌耐药产生机制提供一定的理论依据。     

鲍曼不动杆菌体外诱导耐药及其诱导前后交叉耐药和呼吸耗氧率分析

【背景】鲍曼不动杆菌是院内感染的重要病原菌,因其耐药率高、治疗难度大而备受关注。然而,对于该菌的交叉耐药及耐药相关因素尚未完全阐明。【目的】通过体外诱导分别获得耐美罗培南或耐替加环素的鲍曼不动杆菌菌株,并研究其诱导前后的交叉耐药性和细菌呼吸耗氧率差异。【方法】采用多步法对鲍曼不动杆菌ATCC19606进行体外诱导耐药,PCR扩增诱导前后菌株的16S rRNA基因并测序鉴定,微量肉汤稀释法检测诱导前后鲍曼不动杆菌对美罗培南、亚胺培南、替加环素、阿米卡星、头孢吡肟及左氧氟沙星等抗菌药物的最低抑菌浓度变化,Seahorse XF~e96细胞能量代谢实时测定仪对诱导前后菌株的耗氧率进行分析。【结果】通过88d的体外诱导实验,分别获得耐美罗培南或耐替加环素的鲍曼不动杆菌ATCC19606菌株。耐美罗培南鲍曼不动杆菌ATCC19606对替加环素、亚胺培南、阿米卡星、左氧氟沙星仍处于敏感状态,但是对头孢吡肟交叉耐药;耐替加环素鲍曼不动杆菌ATCC19606对美罗培南、亚胺培南、阿米卡星、左氧氟沙星及头孢吡肟仍处于敏感状态。鲍曼不动杆菌ATCC19606被美罗培南或替加环素诱导耐药之后的耗氧率均下降,差异均具有统计学意义。【结论】美罗培南的使用不仅可能诱导鲍曼不动杆菌ATCC19606对美罗培南耐药,也可能会导致该菌对其它一种或几种抗菌药物产生交叉耐药。鲍曼不动杆菌ATCC19606对美罗培南或替加环素耐药后其耗氧率下降,从而说明呼吸耗氧率下降可能是该菌耐药的因素之一。     

脱发相关差异表达基因的生物信息学分析

利用生物信息学方法分析脱发相关差异表达基因,有望帮助了解脱发发生发展的分子机制。本研究从NCBI的子数据库GEO中选择基因表达谱GSE45512和GSE45513数据集,利用R语言limma工具包,筛选出两个物种斑秃样本与正常样本的共同显著差异表达基因。对这部分基因进行功能注释和蛋白互作网络分析,同时对全部差异表达基因进行基因集富集分析。结果发现,人头皮斑秃样本共筛选出225个差异表达基因;C3H/HeJ小鼠自发斑秃皮肤样本共筛选出337个差异表达基因;两个物种的共同显著差异表达基因有23个。GO功能富集分析和蛋白互作网络分析显示,这部分差异基因显著富集于免疫相关功能,并且彼此间存在蛋白互作关系。基因集富集分析显示两个物种的差异基因都能显著富集到趋化因子信号通路、细胞因子受体相互作用、金葡菌感染及抗原加工与呈递通路;而且人的下调差异基因不仅映射到了人类表型数据库的脱发表型,也映射到皮肤附属物病理相关表型。综上所述,本研究通过生物信息方法分析脱发皮肤组织与正常皮肤组织的差异表达基因,最终筛选出23个在人和小鼠中共同存在的显著差异表达基因;此外,分析发现脱发与免疫过程及皮肤附属物病变密切相关,这些结果为脱发的诊断和治疗提供了新思路。     

Effects of extraction methods on physicochemical properties and hypoglycemic activities of polysaccharides from coarse green tea

Glycoconjugate Journal - Coarse tea is made of mature tea plant (Camellia sinensis L.) shoots and is generally discarded as a worthless crop product, but has been proved an excellent material for...     

Genome-wide analysis of the Chinese sturgeon sox gene family: identification,characterisation and expression profiles of different tissues

The sox family is assumed to be responsible for a number of developmental systems. Genome sequencing technology makes it possible to scan sox genes and conduct characteristic analyses of different species. In fish, full characterisation of sox genes at the genome-wide level has been reported for pufferfish Takifugu rubripes, medaka Oryzias latipes, tilapia Oreochromis niloticus and channel catfish Ictalurus punctatus. However, no systematic investigation of the sox family in sturgeons (Acipenseridae) has been reported to date. This study conducted genome-wide identification of the sox genes in the Chinese sturgeon Acipenser sinensis and profiled their tissue distribution between male and female individuals. In total, 19 sox genes were identified, including soxb1, b2, c, d, e, f and h, in the Chinese sturgeon. Genomic structure analysis indicated relatively conserved exon–intron structures in each sox group and phylogenetic analysis supported the previous classification of the sox family. Most of the sox genes showed a tissue-specific expression pattern, indicating the possible involvement of Chinese sturgeon sox genes at different developmental processes such as cardiac and gonadal development. This study provides a comprehensive resource of Chinese sturgeon sox genes and enables a better understanding of the evolution and function of the sox family.