Establishment and characterization of a new cell line derived from human colorectal laterally spreading tumor

AIM:To study the molecular mechanism of laterally spreading tumor (LST), a cell line [Laterally Spreading Tumor-Rectum 1 (LST-R1)] was derived and the characteristics of this cell line were investigated. METHODS:A new cell line (LST-R1) originated from laterally spreading tumor was established. Properties of the cell line were characterized using scanning and transmission electron microscopy, immunohistochemistry method, cytogenetic analysis and nude mice xenograft experiments. In vitro invasion assay, cDNA microarray and Western blotting were used to compare the difference between the LST-R1 and other colorectal cancer cell lines derived from prudent colon cancer. RESULTS:Our study demonstrated that both epithelial special antigen (ESA) and cytokeratin-20 (CK20) were expressed in LST-R1. The cells presented microvilli and tight junction with large nuclei. The karyotypic analysis showed hyperdiploid features with structural chromosome aberrations. The in vivo tumorigenicity was also demonstrated in nude mice xenograft experiments. The invasion assay suggested this cell line has a higher invasive ability. cDNA microarray and Western blotting show the loss of the expression of E-cadherin in LST-R1 cells.CONCLUSION:We established and characterized a colorectal cancer cell line, LST-R1 and LST-R1 has an obvious malignant tendency, which maybe partially attributed to the changes of the expression of some adhesion molecules, such as E-cadherin. It is also a versatile tool for exploring the original and progressive mechanisms of laterally spreading tumor and the early colon cancer genesis.

Adsorption of β-Naphthalenesulfonic Acid/Sulfuric Acid from Their Solution by Weakly Basic Resin

Experiments for single and bisolute competitive adsorption were carried out to investigate the adsorption behavior of β-naphthalenesulfonic acid(NSA and sulfuric acid from their solution at 25℃ onto weakly basic resin D301R,Adsorption affinity of sulfuric acid on D301R was found to be much higher than that of NSA.The data of single-solute adsorption were fitted to the Langmuir model and the Freundlich adsorption model.The ideal adsorbed solution theory(IAST) coupled with the single-solute adsorption models were used to predict the bisolute competitive adsorption equilibria.The IAST coupled with the Langmuir and the Freundlich model for sulfuric acid and NSA.Respectively,yields the favorable representation of the bisolute competitive adsorption behavior.

电活性导电聚合物组织工程支架材料研究进展

由于具有电活性,导电聚合物在神经和心肌等电刺激响应性细胞的培养及相关电活性组织工程支架的研究中具有潜在的应用前景,而通过键合氨基酸基团或与天然蛋白共混可以提高其生物相容性。本文主要综述两种典型的导电聚合物-聚吡咯和聚苯胺(PANi)在组织工程支架方面的研究进展,并特别阐述短肽与PANi的共价键合和电纺PA-Ni/明胶共混纳米纤维的研究。

Synthesis and Crystal Structure of Co(DMSO)_2(H_2O)_2(SCN)_2 with One-dimensional Hydrogen-bonded Structure (DMSO = Dimethylsulfoxide)

The title complex Co（DMSO）2（H2O）2（SCN）2 has been prepared and structurally characterized. It crystallizes in monoclinic, space group P21/n with a= 5.1981（9）, b = 11.944（2）, c = 12.646（2） A,β = 98.686（2）°, V = 776.2（2） A^3, C6H16CoN2O4S4, Mr = 367.38, Z = 2, De = 1.572 g/cm^3, F（000） = 378 and μ（MoKa） = 1.646 mm^-1. The structure was refined to R= 0.0232 and wR = 0.0645 for 1241 observed reflections with I 〉 2σ（I）. In the title complex, each Co（II） atom is octahedrally coordinated by four O atoms from two DMSO ligands and two water molecules as well as two N atoms from SCN^- ions. The title molecules are connected to each other through intermolecular hydrogen bonds to form a 1-D structure extended by eight-membered Co2O4H2 rings.

Recovery of Copper and Cobalt from Converter Slag with a New Flotation Method Using H_(2）S

In this study,two different samples were obtained from Küre Copper factory.It was determined that the samples contain:the sample of K.C.F.(Küre Copper Factory),0.70%Cu and 0.5%Co.This sample was firstly grounded at-100 mesh dimension.Flotation was done according to previously obtained optimum flotation conditions.The flotation yield of Cu and Co in concentrate phase was found to be low by collective flotation.Even when the samples were grounded at-160 mesh,no change was observed in the flotation result.Especially,Co could not float under the flotation conditions of the non-sulfurized samples.There,a new flotation method was applied which was not applied until now.For this aim,the samples were firstly sulphurised under the steam of H2S+H2O.By this method,the amount of Cu and Co in the samples get rich.According to the obtained results,the optimum reactions for flotation and sulphurization were determined.In the first sulphurization conditions for the sample of K.C.F.,the yield of flotation for the Co and Co were found to be 98.27%and 68.07%,respectively.The results indicate that Cu can be floated at low yield in the original samples.On the other hand,Co cannot float under these conditions.

Intensive-visible-light-responsive ANbO_(2)N(A = Sr, Ba) synthesized from layered perovskite A_(5)Nb_(4)O_(15) for enhanced photoelectrochemical water splitting

Nb-based, perovskite-type oxynitrides ANb(O,N)_(3)(A = Sr, Ba) have been significantly attractive semiconductor materials for photoelectrochemical(PEC) water splitting due to their absorption abilities of intensive-visible-light. However, PEC activities of these perovskites are relatively low due to reduction of Nb species during nitridation leading to the generation of anion defects and impurity phases.Herein, we propose nitridation of A-rich, layered perovskite A_(5)Nb_(4)O_(15) as starting oxides for general synthesis of photoactive ANbO_(2)N. These layered perovskite A_(5)Nb_(4)O_(15) were completely transformed to single phase perovskite-type ANbO_(2)N by nitridation. Wavelength onsets of light absorption were observed at 700 nm for SrNbO_(2)N and at 740 nm for BaNbO_(2)N. According to X-ray photoelectron spectroscopy results,excess Lewis base A species significantly suppressed the generation of reduced species such as Nb^(4+) and Nb^(3+)during nitridation, although it led to an amorphous surface of the as-prepared oxynitride.Subsequent annealing in Ar largely enhanced surface crystallinity of ANbO_(2)N. As a result, Co(OH)_(x)/ANbO_(2)N/FTO photoanodes, prepared by loading Co(OH)_(x) electrocatalyst, showed high photocurrent density of 1.6(A = Sr) and 2.4 m A cm^(-2)(A = Ba) at 1.23 VRHEunder AM 1.5 G simulated sunlight. These results demonstrate that A-rich layered perovskite A_(5)Nb_(4)O_(15)are effective starting precursors for preparing lowdefective ANbO_(2)N, thus improving PEC water splitting activity.

An Inherent Chiral Calix[4]arene Bearing Chiral Groups without Forming Sub-ring

The NMR spectra revealed that the calixarene frame of 1, 3-disubstituted calix[4]arenes beating optically active groups is asymmetric, even without the formation of a sub-ring. This inherent chirality arises from the interaction of the two chiral groups, which hinder the substituents＇ free rotation. Thus, these chiral calix[4]arenes display good chiral recognition ability.

Coupling boron-modulated bimetallic oxyhydroxide with photosensitive polymer enable highly-active and ultra-stable seawater splitting

Seawater photoelectrolysis is showing huge potential in green energy conversion field,yet it is still a formidable challenge to develop one catalyst that can drive the electrolysis reaction stably,economically and efficiently.Motivated by this point,the inorganic–organic hybridization strategy is proposed to insitu construct one hierarchical electrode via concurrent electroless plating and polymerization,which assures the growth of boron-modulated nickel–cobalt oxyhydroxide nanoballs and photosensitive polyaniline nanochains on the self-supporting Ti-based foil(B-Co Ni OOH/PANI@TiO_(2)/Ti).Upon inducing photoelectric effect(PEE),the designed target electrode delivers overpotentials as low as 196 and 398 mV at 100 mA cm^(-2)for hydrogen evolution reaction(HER)and oxygen evolution reaction(OER),respectively,corresponding to an activity enhancement by about 15%as compared to those without PEE.Inspiringly,when served as bifunctional electrocatalysts for overall seawater electrolysis,it can stably maintain at 200 mA cm^(-2)with negligible decay over 72 h.Further analysis reveals that the exceptional catalytic performance can be credit to the B-CoNiOOH,polyaniline(PANI)and TiO_(2)subunit coupling-induced physically and chemically synergistic catalysis effect such as admirable composition stability,photoelectric function and adhesion capability.The finding in this contribution may trigger much more broad interest to the novel hybrid catalysts consisting of photosensitive polymer and transition metal-based electrocatalysts.

Occurrence of Fluoride in the Groundwater of Kaltungo Area and Environs, North Eastern Nigeria

The aim of the study is to assess the occurrence of fluoride in the groundwater of Kaltungo area and environs. Consumption of high fluoride waters clearly manifests in the majority inhabitant of the area in form of dental fluorosis especially in the majority of the populace. Thirty groundwater samples were collected from hand-dug wells and boreholes using standard method and were analyzed to determine the fluoride level. The results revealed that the Fluoride in the waters ranges from 0.8 to 1.94 mg/l with a mean value of 1.65 mg/l. No clear variations in fluoride content have been observed in both the borehole samples and those from the hand-dug wells. Ca-Mg-HCO3 and Ca-Mg-Cl are the two major water types obtained in the area, which have a good association with fluoride. Negative correlation is observed between fluoride and temperature, fluoride and magnesium, fluoride and potassium and poor correlation is observed between fluoride and chloride, fluoride and nitrate, fluoride and phosphates which rules out the possibility of anthropogenic source of the fluoride in the waters. Positive correlation between fluoride and iron, indicates that the presence of fluoride in the water is as a result of dissolution of biotite within the host rock (Basalt).

Recent Advances in Enantioselective Reactions of Terminal Unactivated Alkenes

α-Olefins as aliphatic terminal alkenes could be obtained easily from numerous contemporary synthetic reactions as well as petro-chemical industry,and also found in natural products.Compared to the alkenes attaching the directing groups or activating group,the catalytic asymmetric reaction of unactivated terminal alkenes presents great challenges due to the weak electron effect and small steric hindrance effect.This review mainly summarizes the latest progress of the asymmetric reaction of unactivated terminal olefins since 2016.

Bio-inspired Small Molecular Catalysis

What is the most favorite and original chemistry developed in your researchgroup?I hope it's always the next one.How do you get into this specific field?Could you please share some experiences with ourreaders?Nature provides many astonishing catalytic machineries for building up molecular complexity and harnessing energy in the most efficient ways.Nature's recipe for catalysis serves as a starting point to develop new catalyst for synthetic and energy chemistry.

Heavy atom effects benefit organic light emitting diode(OLED)performance

This Highlight is inspired by a recent article in Nature Photonics in which Yang and co-workers [1] from Shenzhen University report new selenium-integrated thermally activated delayed fluorescence(TADF) molecules and their applications in organic light-emitting diodes(OLEDs).This work represents an important development in this field due to the remarkably high efficiency with which light is emitted from the devices.

Formation of Slipped Dimer in 6-Pentafluorophenyl-substituted Olympicenyl Radical

Introduction of substituents to organic radical is important to increase the stability and realize its applications as multifunctional materials.In this work,pentafluorophenyl group was introduced to 6-position of olympicenyl radical(OR)via a newly designed synthetic strategy to afford the fourth OR derivative,OR4.Due to the combined electro-withdrawing effect and steric hindrance of pentafluorophenyl,OR4 was stable and isolable in crystalline state.

基质金属蛋白酶-26(MMP-26)在小鼠胚胎植入过程中的作用

基质金属蛋白酶-26（MMP-26,又称Endometase或基质水解素-2）是MMPs家族的一个新成员,它可在胎盘、子宫以及不同肿瘤细胞系中表达.采用子宫角注射、免疫组化、原位杂交、胚泡与子宫上皮单层培养、免疫印迹、RT-PCR和RNA印迹等多种体内外实验方法研究并报道了MMP-26在小鼠胚胎中的表达以及MMP-26抗体在胚胎植入中的作用.研究表明,MMP-26的mRNA与蛋白在小鼠胚泡中均有强烈的表达.此外,体内研究显示,MMP-26抗体能显著抑制小鼠胚胎的着床;在体外培养体系中,MMP-26抗体可显著抑制小鼠胚泡在子宫上皮单层上的黏附与扩展;同时,MMP-26抗体以剂量依赖关系抑制整合素αV亚基mRNA和蛋白的表达.研究提示,MMP-26可能直接或间接参与滋养层细胞侵入子宫内膜的过程,促使小鼠胚泡成功植入.

Differentially methylated genomic fragments related with sexual dimorphism of rice pests, Sogatella furcifera

Sogatella furcifera （Hovarth） is a major rice pest with sexual dimorphism. The objective of the current research was to monitor differentially cytosine methylation at CCGG sequences in male and female adults of S. furcifera to determine the association between gene methylation and sexual phenotypes using methylation-sensitive representa- tional difference analysis. After the second subtractive hybridization, four differentially methylated DNA bands were obtained and sequenced. Ten different fragments were found. One fragment from the positive hybridization was 120 bp, and highly similar to the tram- track genes from Nasonia vitripennis. Another fragment from the reverse hybridization was 414 bp, and homologous to the 28S rRNA gene of S. furcifera with a similarity rate as high as 99%. We also discussed how DNA methylation of tramtrack and 28S rRNA genes produced effects on sexual differentiation and development. These results provide potential evidence that DNA methylation of some genes may be related to sexual phenotype variations in S.furcifera and will facilitate future studies on the epigenetic mechanisms of insect sexual dimorphism.

Pentagon-Containing Doublet Graphene Fragments with Edge-Dependent Spin/Charge Distribution

The synthesis of stable open-shell hydrocarbon system comprising of pentagon defects and zigzag edges remains unexplored,which can be considered as model compounds for unraveling the spin-localized states in graphene edges.With concise synthetic approaches,twoπ-extended fluorenyl radicals were synthesized and isolated in their crystalline state.X-ray crystallographic analysis and studies on the magnetic,optical and electrochemical properties of neutral and charged species have revealed an interesting edge-dependence of the spin/charge distribution,that is,the spin and charge distribution shifted from the pentagon defects to the zigzag edges with the elongation of conjugation.Such phenomenon was unprecedented for hydrocarbon radicals and can be rationalized by the recovery of Clar Sextets in the dominant resonance structures.Remarkably,one of the radicals exhibited exceptional stability in air-saturated solutions with the half-life time up to 260 d,thus providing opportunities for the applications as electronic materials.

Synthesis and Structure of a Novel Copper(II) Dinuclear Complex with 4,4′-Dipyridyl as the Bridge

With N,N′ bis(benzimidazol 2 yl methyl)amine as the ligand, a novel Cu(II) dinuclear complex was synthesized as a mimetic compound of superoxide dismutase (SOD). The complex was characterized with element analysis, UV and IR spectra. The crystal structure was determined by using X ray diffraction analysis. The crystal structure shows that Cu(II) and its coordinated atoms construct distorted octahedron configuration with oxygen atoms of (ClO - 4) s in the axial directions. The coordinated cations are linked by (ClO - 4) s to form nonplanar sheets. All sheets are linked together into three dimensional network by the intermolecular hydrogen bonds. The result of the activity assay indicates that the complex does have certain biological activity.