苯胺嘧啶衍生物X-9通过下调整合素β1表达抑制肝细胞癌迁移侵袭

整合素在许多肿瘤细胞中高表达,并且参与肿瘤细胞的侵袭转移。在肝细胞癌中,整合素β1被报导高表达,并促进肿瘤细胞的侵袭。目前,对于整合素的表达调控癌细胞机制以及干预其表达进而抑制肿瘤细胞转移的研究较少。本研究探讨利用小分子化合物抑制整合素表达来抑制肿瘤细胞迁移和侵袭的可能。首先,对临床肝癌细胞患者癌组织和癌旁组织中的整合素β1的表达进行检测,发现其在癌组织中的表达显著高于癌旁组织（P<0.05）。对TCGA肿瘤数据库的生物信息学分析结果同样显示,整合素β1的高表达与肝癌的分期（P=0.019）和预后（P=0.013）相关。通过筛选发现,苯胺嘧啶衍生物X09可以抑制肝癌细胞中整合素β1的mRNA和蛋白质的表达（P<0.01）。细胞划痕愈合实验和细胞穿孔实验结果显示,苯胺嘧啶衍生物X-9能够抑制肝癌细胞的迁移和侵袭（P<0.01）。进一步的研究证实,在肝癌细胞中外源表达整合素β1可以逆转X-9对肝癌细胞迁移和侵袭的抑制;而在敲低整合素β1的细胞中,X-9对细胞的迁移和侵袭的抑制被消除。因此,鉴定出苯胺嘧啶衍生物X-9可以通过下调整合素β1表达,进而抑制肝癌细胞的迁移和侵袭。     

Aniline hydroxylase activities of haemoglobin: Kinetics and mechanism

The mechanism of the aniline hydroxylase activity of methaemoglobin in a monooxygenase system consisting of NADH as electron donor, riboflavin, FAD, FMN or methylene blue as electron carrier and methaemoglobin as the terminal oxidase has been studied. Hydrogen peroxide is produced from oxygen in a methaemoglobin-independent process. 4-Aminophenol is subsequently produced peroxidatively by an NADH-dependent process; NADH prevents a further oxidation of 4-aminophenol in the presence of haemoglobin. In the absence of electron carrier, NADH slowly reduces haemoglobin and then oxyhaemoglobin reacts with aniline to give 4-aminophenol. In the absence of electron donor and electron carrier, oxyhaemoglobin and aniline give rise to the reversible production of 4-aminophenol.     

Fuchsine or magenta: the second most famous aniline dye. A short memoir on the 150th anniversary of the first commercial production of this well known dye

During the mid-nineteenth century, it was learned that the distillation of coal tar yielded a mixture of benzene and toluene that could be used for the manufacture of “anilines.” Oxidation with dichromate led to the first synthetic aniline dye, mauveine. The second aniline dye, a crimson red color, now is named fuchsine or magenta. This dye was prepared using the same starting material, but different oxidants, e.g., tin chloride, mercury nitrate, arsenic acid, and nitrobenzene. Unlike mauveine, which is now a chemical curiosity, fuchsine is still in use as a biological stain, especially in Schiff's reagent for detecting aldehydes, industrially as a dye in coloring various materials from textile fibers to ball point pen inks, analytically as a visualization agent for thin layer chromatography, and as an antifungal agent.     

A new fluorescent staining method for callose of microspore mother cells during meiosis

To observe the dynamic behavior of callose of microspore mother cells during meiosis, we developed a convenient, rapid and efficient staining method using an improved carbol fuchsin/aniline blue solution. The stained microspore mother cells during meiosis showed yellowish green callose, red cytoplasm and dark red chromosomes when excited with blue light, which produced a contrasting image with a three-dimensional effect. When stained with only improved carbol fuchsin solution, the cells had red cytoplasm and chromosomes when excited with green light. The improved carbol fuchsin solution can be used to replace other more expensive DNA-specific dyes, such as DAPI and H33258, to reduce experimental costs.     

Esterification Rates of Main Organic Acids in Wines

The esterification rates (ratio of the concentration of an acid in the neutral ethyl ester form to total concentration of the acid) of main organic acids in wines were determined to study the extent of ethyl ester formation of organic acids. The esterification rates ranged from zero to 24.6%. The averaged values of table wines were from 6 to 16% for acetic and lactic acid, from 0.3 to 3.6% for succinic and malic acid, and from zero to 0.1% for tartaric acid. Sherries had higher esterification rates, about 1.6 to 6 times larger, than table wines. It was found that storage time and temperature influence the formation of ethyl esters, and it was suggested that the aging period required for the ester equilibrium is about one year for acetic and lactic acid, and more than two years for succinic, malic and tartaric acid. The possibility and the procedure to control wine quality during the aging process were discussed.     

棉叶中棉酚的快速提取与测定方法研究

棉酚(G)及其相关物甲氧基半棉酚(DHG)、半棉酚酮(HGQ)、半棉酚(HG)、杀实夜蛾素(H1-4)等是棉花中重要的抗虫性萜烯类次生物质.利用高效液相色谱法(HPLC)对棉酚及其相关物进行了分离,测定了棉叶中的棉酚含量,讨论了不同的提取方法和测定条件对结果的影响,给出了一套简便、快速的分析测试方法,同时与紫外-可见分光光度法(苯胺法)的结果进行了对比,认为对于棉花的抗虫性的研究来说,HPLC是比较适宜的方法.     

A dye-binding assay for measurement of the binding of Cu(II) to proteins

We analysed the theory of the coupled equilibria between a metal ion, a metal ion-binding dye and a metal ion-binding protein in order to develop a procedure for estimating the apparent affinity constant of a metal ion:protein complex. This can be done by analysing from measurements of the change in the concentration of the metal ion:dye complex with variation in the concentration of either the metal ion or the protein. Using experimentally determined values for the affinity constant of Cu(II) for the dye, 2-(5-bromo-2-pyridylaxo)-5-(N-propyl-N-sulfopropylamino) aniline (5-Br-PSAA), this procedure was used to estimate the apparent affinity constants for formation of Cu(II):transthyretin, yielding values which were in agreement with literature values. An apparent affinity constant for Cu(II) binding to α-synuclein of ∼1 × 10⁹ M⁻¹ was obtained from measurements of tyrosine fluorescence quenching by Cu(II). This value was in good agreement with that obtained using 5-Br-PSAA. Our analysis and data therefore show that measurement of changes in the equilibria between Cu(II) and 5-Br-PSAA by Cu(II)-binding proteins provides a general procedure for estimating the affinities of proteins for Cu(II).     

A Rapid Method for Macerating Phloem

Sieve cells and sieve tube members can be macerated from the phloem of various organs of woody and herbaceous species by au-toclaving the tissue in a mild macerating medium. This treatment does not digest the primary walls or the callose deposits on the sieve areas and sieve plates of the sieve elements. These cells can then be recognized by the fluorescence of their callose after staining with aniline blue. Sometimes adjacent sieve elements fail to separate and one can observe details of their junctures.     

Insights into a hydration regulating system in Cupressus pollen grains

Background and Aims

Hydration, rupture and exine opening due to the sudden and large expansion of intine are typical of taxoid-type pollen grains. A hemispheric outgrowth external to the exine was observed on Cupressus and Juniperus pollen grains before the intine swelling and exine release. However, the actual existence of this permanent or temporary structure and its precise role in pollen hydration is still being debated. The aim of this paper is to collect information on the actual presence of this peculiar outgrowth on the surface of the Cupressus pollen grain, its structure, composition and function.

Methods

Pollen grains of several Cupressus species were observed using various techniques and methodologies, under light and fluorescence microscopy, phase-contrast microscopy, confocal microscopy, scanning electron microscopy, and an environmental scanning electron microscope. Observations were also performed on other species with taxoid-type pollen grains.

Key Results

A temporary structure located just above the pore was observed on Cupressus pollen grains, as well as on other taxoid-type pollens. It is hemispheric, layered, and consists of polysaccharides and proteins. The latter are confined to its inner part. Its presence seems to regulate the entrance of water into the grains at the beginning of pollen hydration.

Conclusions

The presence of a temporary structure over the pore of taxoid-type pollen grains was confirmed and its structure was resolved using several stains and observation techniques. This structure plays a role in the first phases of pollen hydration.     

苯胺、苯酚对淡水藻类生长的影响

用生物检验法研究了苯胺、苯酚对蛋白核小球藻、斜生栅藻生长的影响,测定了两种藻类在5 d内对不同浓度苯胺、苯酚的降解或在藻细胞内的富集情况.结果表明,苯胺、苯酚对两种淡水藻类的致毒作用有所不同,对于同一种藻类,苯胺毒性大于苯酚;在同一毒物浓度下,栅藻表现更为敏感.在较低浓度下,两种淡水藻类均能降解或吸收一部分有机毒物,其中对苯酚的降解能力较强.