Maternal separation and early stress cause long‐lasting effects on dopaminergic and endocannabinergic systems and alters dendritic morphology in the nucleus accumbens and frontal cortex in rats

A considerable amount experimental studies have shown that maternal separation (MS) is associated with adult offspring abnormal behavior and cognition disorder. Accordingly, this experimental procedure has been proposed as a predictor for alcohol and drug dependence based on the neurodevelopmental soon after birth. Endocannabinoid system (eCBs) has been implicated in reward processes, including drug abuse and dependence. MS and associated stress causes changes in the eCBs that seem to facilitate alcohol consumption. In this study, we seek to evaluate potential morphological changes in neurons of the frontal cortex (FCx) and nucleus accumbens (NAcc), in the expression of receptors and enzymes of the endocannabinoid and dopamine systems and in second messengers, such as Akt, in adult rats subjected to MS and early stress (MS + ES; 2 × 180 min daily) vs. nonseparated rats (NMS). Results showed that MS + ES induces higher D2R expression and lower D3R, FAAH, and MAGL expression compared with NMS rats. Alterations in total dendritic length were also detected and were characterized by increases in the NAcc while there were decreases in the FCx. We believe MS + ES‐induced changes in the dopaminergic and endocannabinergic systems and in the neuronal microstructure might be contributing to alcohol seeking behavior and, potential vulnerability to other drugs in rats. © 2015 Wiley Periodicals, Inc. Develop Neurobiol 76: 819–831, 2016     

Suppression of Recombination Losses in Polymer:Nonfullerene Acceptor Organic Solar Cells due to Aggregation Dependence of Acceptor Electron Affinity

Here, it is investigated whether an energetic cascade between mixed and pure regions assists in suppressing recombination losses in non‐fullerene acceptor (NFA)‐based organic solar cells. The impact of polymer‐NFA blend composition upon morphology, energetics, charge carrier recombination kinetics, and photocurrent properties are studied. By changing film composition, morphological structures are varied from consisting of highly intermixed polymer‐NFA phases to consisting of both intermixed and pure phase. Cyclic voltammetry is employed to investigate the impact of blend morphology upon NFA lowest unoccupied molecular orbital (LUMO) level energetics. Transient absorption spectroscopy reveals the importance of an energetic cascade between mixed and pure phases in the electron–hole dynamics in order to well separate spatially localized electron–hole pairs. Raman spectroscopy is used to investigate the origin of energetic shift of NFA LUMO levels. It appears that the increase in NFA electron affinity in pure phases relative to mixed phases is correlated with a transition from a relatively planar backbone structure of NFA in pure, aggregated phases, to a more twisted structure in molecularly mixed phases. The studies focus on addressing whether aggregation‐dependent acceptor LUMO level energetics are a general design requirement for both fullerene and NFAs, and quantifying the magnitude, origin, and impact of such energetic shifts upon device performance.     

ALS-Linked Mutations Affect UBQLN2 Oligomerization and Phase Separation in a Position- and Amino Acid-Dependent Manner

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宁夏枸杞根和茎的化学成分及抗炎活性研究

研究宁夏枸杞(Lycium barbarum L.)根部和茎部的化学成分。采用硅胶柱、ODS开放柱、Sephadex LH-20葡聚糖凝胶柱及半制备反相高效液相等色谱手段,对宁夏枸杞根和茎部乙醇提取物的石油醚部位及乙酸乙酯部位化学成分进行分离纯化,根据其理化性质以及波谱数据鉴定得到12个化合物,分别为N-[2-(3,4-dihydroxyphenyl)-2-hydroxyethyl]-3-(4-methoxyphenyl)prop-2-enamide(1)、3-(4-hydroxy-3-methoxy phenyl)-N-2-(4-hydroxyphenyl)-2-methoxyethyl]acrylamide(2)、N-trans-coumaroyloctopamine(3)、(E)-2-(4,5-dihydroxy-2-{3-[(4-hydroxyphenethyl)amino]-3-oxopropyl}phenyl)-3-(4-hydroxy-3,5-dimethoxyphenyl)-N-(4-acetamidobutyl)acrylamide(4)、1,2-dihydro-6,8-dimethoxy-7-hydroxy-1-(3,4-dihydroxy-phenyl)-N1,N2-bis[2-(4-hydroxyphenyl)ethyl]-2,3-naphthalene dicarboxamide(5)、(+)-syringaresinol(6)、zhebeiresinol(7)、(±)-eriodictyol(8)、isovanilin(9)、5,5′-dimethoxybiphenyl-2,2′-diol(10)、p-hydroxyphenethyltrans-ferulate(11)、E-ferulic acid hexacosyl ester(12),所有化合物均为首次从该植物中分离得到。此外,采用MTT法和抑制一氧化氮(NO)生成实验,从细胞毒活性和抗炎活性两方面评估了化合物的生物活性。结果表明,化合物2具有显著的抗炎活性,其IC50值(17.00±1.11μmol/L)小于阳性对照药槲皮素的IC50值(17.21±0.50μmol/L)。     

单细胞全基因组扩增技术与应用

同一组织中的细胞往往具有类似的结构和功能,然而通过对单个细胞进行测序分析后,发现每个细胞都具有一定异质性.单细胞全基因组扩增技术是进行单细胞测序的前提,该技术可用于揭示单细胞基因组结构差异,同时在肿瘤研究、发育生物学、微生物学等研究中发挥重要作用,并成为生命科学研究技术的热点之一.单细胞全基因组扩增技术的难点在于单细胞的分离和全基因组的扩增.本文介绍了单细胞全基因组扩增技术中常用的单细胞分离技术和单细胞全基因组扩增技术,并对各技术间的优缺点进行比较,同时着重讨论该技术在肿瘤研究、发育生物学和微生物学研究中的应用.     

雷公藤提取物中主要物质基础及其抗肿瘤活性研究北大核心CSCD

为进一步阐明雷公藤中的主要物质基础,并评价其抗肿瘤活性。该研究采用柱层析、HPLC等技术,对雷公藤提取物进行研究。结果表明:(1)从雷公藤95%乙醇提取物中分离得到12个化合物,根据理化性质及波谱数据鉴定各化合物的结构分别为α,β-amyrenone(1)、3β-acetoxyolean-12-en-28-oic acid(2)、antriptolactone(3)、ω-hydroxypropioquaiacone(4)、3-(4-hydroxy-3-methoxyphenyl)-propenal(5)、3-methoxy-4-hydroxy phenylethanol(6)、vanillin(7)、3,4,5-三甲氧基苯酚(8)、对羟基苯甲酸(9)、对羟基苯甲醛(10)、vanillyl alcohol(11)、2,6-dimethxy-1,4-benzoquinone(12)。其中,化合物1、2、5、12为首次在该属植物中分离得到。(2)采用噻唑蓝(MTT)法对12个化合物进行抗SH-SY5Y细胞株、K562细胞株和Hel细胞株3种肿瘤细胞系细胞增殖活性的筛选,并对活性较好的化合物12进行Hoechst荧光染色和促凋亡作用的检测发现,化合物2、3、5、12具有一定的抗肿瘤活性,其中化合物12的抗肿瘤活性最为显著(SH-SY5Y细胞、Hel细胞、K562细胞的IC_(50)值分别为35.6、14.3、28.8μmol·L^(-1))。该研究结果进一步丰富了雷公藤的化学成分,发现了1个具有明显抗肿瘤活性的单体物质,为雷公藤的进一步开发提供了科学依据。     

Chiral separation of aliphatic primary amino alcohols as o‐phthaldialdehyde/mercaptoethanol derivatives on polysaccharide‐based chiral stationary phases

A sensitive chiral high performance liquid chromatography (HPLC) method for the determination of aliphatic primary amino alcohol isomers with o‐phthaldialdehyde/mercaptoethanol precolumn derivatization has been developed and validated. Seven chiral columns were tested in a reversed phase mode. Excellent enantioseparation with the resolution more than 2.0 was achieved on Chiralcel OJ‐3R. The effect of various chromatographic conditions including column temperature, acetonitrile content in the mobile phase, buffer pH, buffer concentration, and buffer type in the mobile phase on the retention and the selectivity was investigated. The final mobile phase consisted of binary mixture of 20mM ammonium formate solution with acetonitrile (75:25; v/v). The analyses were performed at mobile phase flow rate of 1.0 mL/min and the column temperature of 40°C. The fluorescence detection was performed at excitation wavelength of 345 nm and emission wavelength of 450 nm. The developed method was fully validated in terms of linearity, sensitivity, accuracy, precision, intermediate precision, and selectivity according to International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use guidelines using internal normalization procedure. The proposed chiral method was proved to be highly sensitive, simple, and rapid and was successfully applied to the determination of D‐Valinol content in commercially available samples of L‐Valinol.     

Enantiomeric impurities in chiral catalysts,auxiliaries, and synthons used in enantioselective syntheses. Part 5

The enantiomeric excess of chiral starting materials is one of the important factors determining the enantiopurity of products in asymmetric synthesis. Fifty‐one commercially available chiral reagents used as building blocks, catalysts, and auxiliaries in various enantioselective syntheses were assayed for their enantiomeric purity. The test results were classified within five impurities level (ie, <0.01%, 0.01%‐0.1%, 0.1%‐1%, 1%‐10%, >10%). Previously from 1998 to 2013, several reports have been published on the enantiomeric composition of more than 300 chiral reagents. This series of papers is necessitated by the fact that new reagents are forthcoming and that the enantiomeric purity of the same reagent can vary from batch to batch and/or from supplier to supplier. This report presents chiral liquid chromatography (LC) and gas chromatography (GC) methods to separate enantiomers of chiral compounds and evaluate their enantiomeric purities. The accurate and efficient LC analysis was done using newly introduced superficially porous particle (SPP 2.7 μm) based chiral stationary phases (TeicoShell, VancoShell, LarihcShell‐P, and NicoShell).