Synthesis and evaluation of a novel ‘off-on’ chemical sensor based on rhodamine B and the 2,5-pyrrolidinedione moiety for selective discrimination of glutathione and its bioimaging in living cells

A new “turn-on” fluorescent probe, RDMBM, based on the rhodamine B dye and the 2,5-pyrrolidinedione moiety was synthesized and characterized. Its sensing behavior toward various amino acids was evaluated via UV–vis and fluorescence spectroscopic techniques. The observed spectral changes showed that RDMBM displays high selectivity and sensitivity toward GSH in MeOH/H₂O (1:2, v/v, pH 7.40, Tris-HCl buffer, 1?mM) solution and that it undergoes 1:1 covalent binding with GSH. More importantly, the hydrogenation and ring-opening of the nitrogen atom in the spirane structure of rhodamine B derivatives were tightly bound to the induction effects of different groups. Furthermore, fluorescence imaging applications demonstrated that RDMBM can be successfully used for the detection of GSH in human breast cancer cells MCF-7.     

催化示波极谱法测定农作物中的微量铅

1 前言 农作物中铅的含量在很大程度上反映出土壤和成土母岩中铅的水平。铅是一种有毒元素,人体摄入过量的铅,就会导致一系列的病变。因此,农作物中铅的测定对调查和评价环境中铅的污染,估算人畜食入铅的量,研究各类因铅中毒引起的疾病,做到对症下药具有十分重要的意义。本文根据前人的经验研     

4种鼠尾草属植物根、茎、叶中脂溶性成分的分布差异性

为了说明4种鼠尾草属植物脂溶性成分在根、茎、叶中的分布情况,本文采用了组织化学定位和HPLC图谱分析相结合的方法,对4种鼠尾草属植物不同部位的脂溶性成分进行了分析.结果表明:4种鼠尾草属植物的根、茎、叶中脂溶性成分的分布有差异,根中脂溶性成分分布于周皮,茎、叶中脂溶性成分分布于表皮.丹参和白花丹参根中的脂溶性成分主要是丹参酮ⅡA、丹参酮Ⅰ和二氢丹参酮Ⅰ,鼠尾草和药用鼠尾草根中仅含丹参酮ⅡA,不含丹参酮Ⅰ和二氢丹参酮Ⅰ.茎、叶中的脂溶性成分不是丹参酮ⅡA、丹参酮Ⅰ和二氢丹参酮Ⅰ.脂溶性成分的种类和含量随品种和引种地的不同而产生差异.这一结果明确了脂溶性成分在4种鼠尾草属植物不同部位的确切分布,为准确用药提供了依据.     

Analysis of Xyloglucan Endotransglycosylase/Hydrolase (XTH) Genes and Diverse Roles of Isoenzymes during Persimmon Fruit Development and Postharvest Softening

Xyloglucan endotransglycosylase/hydrolase (XTH) enzymes have played a role in the remodeling of cell wall hemicelluloses. To investigate the function of XTHs in persimmon (Diospyros kaki L.) fruit development and postharvest softening, five cDNAs (DkXTH1 to DkXTH5), whose putative proteins contained the conserved DEIDFEFLG motif of XTH, were cloned. Real time quantitative PCR analysis revealed that DkXTH1, DkXTH4, and DkXTH5 peaked in immature expanding fruit, and their higher expression was observed along with higher fruit firmness in cold-treated fruit or firmer cultivar fruit during storage. The opposite gene expression patterns were observed in DkXTH2 and DkXTH3, which reached maxima concomitance with pronounced fruit softening. Meanwhile, the xyloglucan endotransglycosylase (XET) enzymes play important roles in both the rapid growth and ripening of persimmon fruit. Furthermore, the recombined DkXTH1 and DkXTH2 proteins showed significant XET activity without any detected XEH activity. However, the XET activity of recombined DkXTH2 protein had a higher affinity for small acceptor molecules than that of recombined DkXTH1 protein. The former might prefer to participate in cell wall restructuring, and the latter is more inclined to participate in cell wall assembly. Besides, DKXTH proteins could function by targeting to the cell wall under regulation of a signal peptide. The data suggested that individual DKXTHs could exhibit different patterns of expression, and the encoded products possessed specific enzymatic properties conferring on their respective functions in growth and postharvest softening of persimmon fruit.     

Wheat genomic study for genetic improvement of traits in China

Science China Life Sciences - Bread wheat (Triticum aestivum L.) is a major crop that feeds 40% of the world’s population. Over the past several decades, advances in genomics have led to...     

Genome-Wide Association and Expression Analysis Revealed the Candidate Variants and Molecular Underpinnings of Cold-Stress Response in Large Yellow Croaker

Marine Biotechnology - Large yellow croaker (Larimichthys crocea) is one of the most economically important fish in China. Recently, global climate change has caused more and more intense and...     

非小细胞肺癌患者中EGFR突变、ALK和ROS1融合基因表达变化及其临床病理学意义

目的探讨非小细胞肺癌(non-small cell lung cancer,NSCLC)患者中表皮生长因子受体(epidermic growth factor receptor,EGFR)突变、间变性淋巴瘤激酶(anaplastic lymphoma kinase,ALK)和ROS1融合基因的表达情况及其与临床病理特征的关系。方法应用ARMS法检测379例非小细胞肺癌患者中EGFR突变、ALK和ROS1融合基因的表达情况,并分析其与患者临床病理特征的关系。结果 379例非小细胞肺癌患者组织中,EGFR突变率为36.15%(137/379),19del和L858R突变为其主要突变类型,同时检出L858R和T790双突变4例,L858R和19del双突变2例;EGFR突变人群主要是女性、腺癌、非吸烟患者(P<0.05)。ALK融合基因阳性率为3.43%(13/379),其中ALK-M1融合基因型4例,ALK-M2融合基因型3例,ALK-M3融合基因型3例,ALK-M4融合基因型1例,ALK-M6融合基因型2例。ROS1融合基因阳性率为3.17%(12/379),主要为ROS1-M8融合基因型(8例),存在1例ROS1-M3和ROS1-M8融合基因型双融合。不同性别、年龄、组织学和吸烟状况的NSCLC患者ALK和ROS1基因突变率无统计学差异。结论 EGFR基因在NSCLC患者中存在较高的突变率,而ALK、ROS1融合基因在NSCLC患者中突变率较低,但代表了非小细胞肺癌的特点分子亚型,为指导临床靶向治疗提供依据。     

Cosupplementation with a synthetic, lipid-soluble polyphenol and vitamin C inhibits oxidative damage and improves vascular function yet does not inhibit acute renal injury in an animal model of rhabdomyolysis

We investigated whether cosupplementation with synthetic tetra-tert-butyl bisphenol (BP) and vitamin C (Vit C) ameliorated oxidative stress and acute kidney injury (AKI) in an animal model of acute rhabdomyolysis (RM). Rats were divided into groups: Sham and Control (normal chow), and BP (receiving 0.12% w/w BP in the diet; 4 weeks) with or without Vit C (100mg/kg ascorbate in PBS ip at 72, 48, and 24h before RM induction). All animals (except the Sham) were treated with 50% v/v glycerol/PBS (6 mL/kg injected into the hind leg) to induce RM. After 24h, urine, plasma, kidneys, and aortae were harvested. Lipid oxidation (assessed as cholesteryl ester hydroperoxides and hydroxides and F(2)-isoprostanes accumulation) increased in the kidney and plasma and this was coupled with decreased aortic levels of cyclic guanylylmonophosphate (cGMP). In renal tissues, RM stimulated glutathione peroxidase (GPx)-4, superoxide dismutase (SOD)-1/2 and nuclear factor kappa-beta (NFκβ) gene expression and promoted AKI as judged by formation of tubular casts, damaged epithelia, and increased urinary levels of total protein, kidney-injury molecule-1 (KIM-1), and clusterin. Supplementation with BP±Vit C inhibited the two indices of lipid oxidation, down-regulated GPx-4, SOD1/2, and NF-κβ gene responses and restored aortic cGMP, yet renal dysfunction and altered kidney morphology persisted. By contrast, supplementation with Vit C alone inhibited oxidative stress and diminished cast formation and proteinuria, while other plasma and urinary markers of AKI remained elevated. These data indicate that lipid- and water-soluble antioxidants may differ in terms of their therapeutic impact on RM-induced renal dysfunction.     

Revealing genetic diversity of tree peonies at micro-evolution level with hyper-variable chloroplast markers and floral traits

Key message

Highly variable regions of chloroplast genome were found to be useful in the detection of plant genetic diversity at micro-evolution level. Our methodology will improve understanding and conservation of plant diversity.

Abstract

Tree peonies are famous flowers with about 2,000 cultivars in the world, belonging to Paeonia sect. Moutan of the Paeoniaceae. They are traditionally classified based on flower forms and colors. Due to the limited number of DNA and morphological markers, and the existence of synonyms and homonyms, evaluation on genetic diversity of so many cultivars remains a challenge. In most cases, it is difficult and even impossible to discriminate tree peony cultivars when they are not in flower. In this study, single nucleotide polymorphism detected from the hyper-variable regions of chloroplast genome was employed to separate tree peony cultivars into different maternal lineages which can be expressed briefly by a nucleotide molecular formula. Our approach enabled a much higher resolution of cultivar identification and classification that has not been obtained before. The newly developed hyper-variable chloroplast markers, as an independent source of taxonomic characteristics, provided novel evidences and higher resolution ability that are helpful in building an effective classification system for evaluation, conservation, and utilization of the tree peony germplasm resources at cultivar level.