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By utilizing three ligands derived from cyclotriphosphazene, three novel cadmium-based coordination polymers (CPs), namely, {[Cd3(L1)(H2O)5]}n (1), {[Cd4(H2L2)2(H2O)8]}n (2) and {[Cd2(H2L3)2(H2O)2]·(H2O)}n (3), (H6L1 = hexakis(4-carboxylatophenoxy)cyclotriphosphazene, H6L2 = hexakis(3-carboxylatophenoxy)cyclotriphosphazene, H6L3 = hexakis(4-(1H-tetrazol-5-yl)phenoxy)cyclotriphosphazene), have been successfully synthesized and structurally characterized. Their distinct topological architectures must be ascribed to the coordination conformations of the flexible ligands along with the different sites and coordination modes of the coordination groups. 1 exhibits a 3D topological structure based on the connection of trinuclear units and fully deprotonated L1 ligands. Just by changing the position of the carboxylate groups, a 2D layer structure with dinuclear units and partially deprotonated L2 ligands has been constructed. Comparably, by substituting the carboxylate by tetrazole groups, a distinct 3D structure with tetranuclear units has been synthesized. In addition, the three Cd CPs exhibit the corresponding photo-chemical properties in accordance with their structures.

ObjectiveVentral anterior homeobox 2 (VAX2) gene is a key regulating factor for the development of the ventral region of the eye, and has recently attracted much attention from the cancer treatment field. Our study aimed to explore the effect of VAX2 on papillary thyroid carcinoma (PTC).MethodsWe determined the expression levels of VAX2 in PTC based on The Cancer Genome Atlas (TCGA) database. We then assessed the prognosis of patients with PTC, and analyzed the association between VAX2 expression and clinicopathological characteristics. Subsequently, we measured the biological functions of VAX2 in PTC using qRT-PCR, cell counting kit-8 (CCK-8) assay, colony formation assay, wound healing assay, transwell assays and western blot.ResultsVAX2 was up-regulated in PTC tissues when compared with normal thyroid tissues, and high expression level of VAX2 was positively correlated with poor prognosis. Furthermore, knockdown of VAX2 significantly inhibited the proliferation, migration and invasion of PTC cells. Importantly, through western blot analysis, we found that the expression of phosphorylated-(p) ERK and p-MEK in ERK signaling pathway showed a significant decrease after knockdown of VAX2.ConclusionThese findings suggest that VAX2 may be involved in the malignant progression of PTC, and hold significant potential as a therapeutic target for PTC.

Objective To explore the relationship between Helicobacter pylori (Hp) infection and colorectal cancer in different continents or economic conditions. Methods Published case-control studies dealing with the correlation of colorectal cancer with Hp infection were retrieved from PubMed, EMBASE, High Wire Press, Ovid, Medline and EBSCO. Meta-analysis was performed by using RevMan 5.3 software. We selected the OR and 95% CI as indicators of the analysis according to different continents (Asia, Europe, and America) and economic conditions (developed countries and developing countries). Results A total of 23 studies dealing with the correlation of colorectal cancer with Hp infection were included in the present meta-analysis, and there was a total sample of 182,561 patients, including 88,378 cases in Hp positive group and 94,183 cases in Hp negative group. The results of meta-analysis showed the OR was 1.42 (95%CI 1.38-1.46). Geographically, the correlation was low in Asian countries (OR=1.29, 95%CI 1.13-1.48), and was highest in American countries (OR=1.44, 95%CI 1.39-1.48). According to the economic conditions, the correlation was low in developing countries (OR=1.17, 95%CI 1.01-1.37), and was higher in developed countries (OR=1.43, 95%CI 1.39-1.47). Conclusions Hp infection is a risk factor for colorectal cancer. It seems that there is a close relation ship between its incidence and geography, and also economic condition. DOI: 10.11855/j.issn.0577-7402.2015.03.13

This article presents the dependence of porous silicon (PSi) morphology on preparation conditions and the coalition between morphology and optical properties. p-type (100) silicon wafers were etched in an electrolyte incorporating 1:1 (by volume) ethanol and aqueous solution of hydrofluoric acid (40 wt. %) at various etching current densities and times. Detailed information about evolution of PSi morphology with variation of preparation conditions was investigated by field emission scanning electron microscopy (FESEM) and atomic force microscope (AFM). The results have shown that the pore sizes of PSi are gradually increasing, and the thicknesses of PSi layer are increased with the speed of about 11-12 nm/s as the etching duration increased. Addition, the optimal photoluminescence of PSi is achieved in room temperature with the strongest photoluminescence spectra when the corrosion current density was 30 mA / cm2 with 30 min etching time.

As a novel functional nanomaterial, porous silicon has many unique properties, such as its unique optical characteristics, biocompatibility, abundance, mechanical, electronic properties, silicon microelectronic compatibility, filtration, nanometer micropore controllable growth and large specific surface area, which enhance its prospect in the biological analysis, immune virus detection, environmental, food industry and so on, and has attracted world interests in the fields of materials science, biology, medicine, and electronics. In this work the application of porous silicon in the fields of biological and biomedical has been introduced with depth and width of researching on its.

Monocrystalline Cu nanocolloid with 4.3 nm average particle size and 2.3～9.5 nm particle size distribution was successfully synthesized in situ by liquor-phase reduction synthesis, using copper acetate tetrahydrate as precursor, ascorbic acid as reductant, polyethylene sorbitan monooleate （Tween-80） as modifier, and liquid paraffin as solvent. The as-prepared copper nanocolloid was characterized by XRD, SAED, and TEM. Nano-lubricating oil with excellent dispersibility, chemical stability, and compatibility with other additives verified by TG-DSC, was achieved via adding as-prepared nano-copper into Mobil 1 5w-30 lubricating oil. The nano-lube’s physiochemical properties were characterized according to Chinese national standard. The tribological behavior of nano-lubricant was investigated on ball-on-disk UMT-Ⅱ tribometer and four-ball tribometer. The worn surface morphology was analyzed by means of SEM and EDS. Experimental results show as follows. The Mobil 1 5w-30 lube’s tribological property is markedly enhanced with the as-prepared copper nanocolloid as its additive. The as-prepared nano-Cu agglomerate discontinuous deposited, extrude, melt, spread, and form a film in micro-defects on the worn surfaces, then improve the friction-reducing, anti-wear ability, extreme pressure value, and extreme working ability of Mobil 1 5w-30 lubricant.

Porous silicon (PS) with 6.13 nm average pore diameter, 20.6μm thickness layer and 70.8% porosity prepared by galvanostatic electrochemical anodisation of p-type silicon wafer in aqueous hydrofluoric acid (HF)/ethanol electrolyte. The freshly prepared PS was processed by time effect, nitric acid treatment, cathodic reduction, and hydrogen peroxide treatment, respectively. Samples were characterized and analyzed by field emission scanning electron microscopy (FESEM), P hotolumimescence (PL) and X-ray photoelectron spectroscopy (XPS) before and after post-processing. The PL spectra showed that PS had three PL peaks near to 425 nm, 486 nm and 530 nm, respectively, the strongest luminous intensity at 425nm obtained when PS followed 6h in hydrogen peroxide post-processing, and the difference effect on PL via various post-processing were also discussed. From XPS spectra analysis, the surface composition of PS via different post-processing method was carried out that the oxygen mainly existed in the form of Si-O.