Circular RNAs acting as ceRNAs mediated by miRNAs may be involved in the synthesis of soybean fatty acids

Functional & Integrative Genomics - Soybean oil is composed of fatty acids and glycerol. The content and composition of fatty acids partly determine the quality of soybean seeds. Circular RNAs...     

Double-sides sticking mechanism of vinblastine interacting with α,β-tubulin to get activity against cancer cells

Abstract

Vinblastine (VLB) and its derivatives have been used for clinical first-line drugs to treat various cancers. Due to the resistance and serious side effects from using VLB and its derivatives, there is a need to discover and develop novel VLB derivatives with high activity against cancer cells. In order to better discover and develop new VLB derivatives, we need to study the structural basis of VLB's anti-cancer cytotoxicity and the mechanism of its interaction with α,β-tubulins. Based on the crystal structure of α,β-microtubule complex protein, the molecular dynamics method including the sampling PMF method was used to study the variation of dissociation free energy (ΔG) of α,β-tubulins under different system conditions, and then from which to study the mechanism of the interaction between VLB and α,β-tubulins. The obtained results show that the dissociation of pure α,β-tubulins requires 197.8?kJ·mol^?1 for ΔG. When the VLB molecule exists between the interface of α,β-tubulins, the dissociation ΔG of α,β-tubulins reaches 220.5?kJ·mol^?1, which is greater than that of pure α,β-tubulin. The VLB molecule is formed by connecting a vindoline moiety (VM) molecule with a catharanthine moiety (CM) molecule through a carbon-carbon bond, which is a larger molecule. When the CM molecule exists in the middle of α,β-tubulin interface, the dissociation ΔG of α,β-tubulins is 46.2?kJ·mol^?1, during which the CM moves with β-tubulin. When the VM molecule exists between the middle of α,β-tubulin interface, the dissociation ΔG of α,β-tubulins is 86.7?kJ·mol^?1, during which it moves with α-tubulin. Therefore, the VLB molecule is like a double-sides tape to stick α-tubulin and β-tubulin together. The VLB molecule intervenes the dynamic equilibrium between dissociation and aggregation of α-tubulin and β-tubulin by a double-sides sticking mechanism to exert high activity with toxicity against cancer cell. Besides, our results demonstrate that VLB has its structural basis for anticancer cytotoxicity due to its two compositions composed of a CM molecule and a VM molecule although they have little toxicity against cancer cell alone.     

Identifying Individuals with Antisocial Personality Disorder Using Resting-State fMRI

Antisocial personality disorder (ASPD) is closely connected to criminal behavior. A better understanding of functional connectivity in the brains of ASPD patients will help to explain abnormal behavioral syndromes and to perform objective diagnoses of ASPD. In this study we designed an exploratory data-driven classifier based on machine learning to investigate changes in functional connectivity in the brains of patients with ASPD using resting state functional magnetic resonance imaging (fMRI) data in 32 subjects with ASPD and 35 controls. The results showed that the classifier achieved satisfactory performance (86.57% accuracy, 77.14% sensitivity and 96.88% specificity) and could extract stabile information regarding functional connectivity that could be used to discriminate ASPD individuals from normal controls. More importantly, we found that the greatest change in the ASPD subjects was uncoupling between the default mode network and the attention network. Moreover, the precuneus, superior parietal gyrus and cerebellum exhibited high discriminative power in classification. A voxel-based morphometry analysis was performed and showed that the gray matter volumes in the parietal lobule and white matter volumes in the precuneus were abnormal in ASPD compared to controls. To our knowledge, this study was the first to use resting-state fMRI to identify abnormal functional connectivity in ASPD patients. These results not only demonstrated good performance of the proposed classifier, which can be used to improve the diagnosis of ASPD, but also elucidate the pathological mechanism of ASPD from a resting-state functional integration viewpoint.     

Protective effect of L-theanine on carbon tetrachloride-induced acute liver injury in mice

We studied effects of L-theanine, a unique amino acid in tea, on carbon tetrachloride (CCl(4))-induced liver injury in mice. The mice were pre-treated orally with L-theanine (50, 100 or 200 mg/kg) once daily for seven days before CCl(4) (10 ml/kg of 0.2% CCl(4) solution in olive oil) injection. L-theanine dose-dependently suppressed the increase of serum activity of ALT and AST and bilirubin level as well as liver histopathological changes induced by CCl(4) in mice. L-theanine significantly prevented CCl(4)-induced production of lipid peroxidation and decrease of hepatic GSH content and antioxidant enzymes activities. Our further studies demonstrated that L-theanine inhibited metabolic activation of CCl(4) through down-regulating cytochrome P450 2E1 (CYP2E1). As a consequence, L-theanine inhibited oxidative stress-mediated inflammatory response which included the increase of TNF-α and IL-1β in sera, and expression of cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) in livers. CCl(4)-induced activation of apoptotic related proteins including caspase-3 and PARP in mouse livers was also prevented by L-theanine treatment. In summary, L-theanine protects mice against CCl(4)-induced acute liver injury through inhibiting metabolic activation of CCl(4) and preventing CCl(4)-induced reduction of anti-oxidant capacity in mouse livers to relieve inflammatory response and hepatocyte apoptosis.     

国家公园自然资源保护分区研究——以北京长城国家公园体制试点区为例

合理的资源保护分区有助于提高国家公园自然资源保护措施的区域针对性,增强保护效果。以北京长城国家公园体制试点区为例,从"生态本底"、"资源特征"以及"人类干扰"三方面选取要素指标,构建了国家公园自然资源保护分区指标体系。将林小班作为分区单元,根据园区的生态本底特征将其划分为7个自然资源保护区,并以此作为国家公园开展资源调查和管理工作的基本区划单位;根据各区域具体的资源问题和保护需求将国家公园进一步细分为17种自然资源保护区域,形成了包含两个层次的自然资源保护分区方案,并基于各个保护区的保护目标提出了相应的保护措施。该分区方案避免了国家公园现存的各类用地空间布局交叉或错位所导致的难以协调问题,有利于实现国家公园自然资源保护分区方案的落地和自然资源的有效保护。     

二阶段等距抽样

本文提出了二阶段等距抽样的概念．分第二阶段样本为等距抽样和SRSWOR两种情况讨论了总体平均值的估计问题．在第二阶段抽样为SRSWOR情况下，讨论了辅助信息的利用问题，提出了总体平均值的比型估计和回归型估计．并通过一个实际计算的例子，对文中提出的不同估计量进行了比较．