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BackgroundThe research of low temperature detergent is of great significance for the operating and decommissioning of nuclear facilities at low temperature environment.PurposeThis study aims to explore the fluid characteristics and decontamination characteristics of polyvinyl butyral detergent at low temperature.MethodsThe low temperature detergent was prepared by using polyvinyl butyral as solute, ethanol and ethyl acetate as solvent and citric acid as decontamination additives. The viscosity, fluidity, sprayability and wettability of the detergent on the surface of different materials were measured in experiment. Four simulated U(VI) contaminated plate samples were prepared by the dyeing of the uranyl nitrate solution on the base of glass, stainless steel, ceramic tile and alkyd paint, respectively. Scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDX) were used to characterize the decontamination films on the surface of these four samples, and study the decontamination mechanism. Finally, the decontamination characteristics of the detergent for the simulated U(VI) pollution on surface of different materials were studied at low temperature, and the effects of temperature, detergent dosage and surface roughness on decontamination rate were discussed.ResultsExperimental results show that the decontamination rates of the detergent for the simulated U(VI) pollution on the surface of glass, stainless steel, ceramic tile and alkyd paint board are above 97.3%, 93.6%, 95.5% and 88.9%, respectively, in the temperature range of -15~10 ℃, that the temperature and the detergent dosage have little effect on the decontamination rate and that the decontamination film formed by the detergent have good strippability.ConclusionsThe detergent has a good application potential at the decontamination of radioactive pollution in low temperature environment.

The long intergic non-protein coding RNA 460 (LINC00460) is abnormally highly expressed in gastrointestinal tumors and plays an important role in promoting tumor formation and development. LINC00460 is mainly distributed in cytoplasm and has many abnormal gene variants of single nucleotide polymorphism in tumors. LINC00460 can promote the proliferation, metastasis, angiogenesis, radiotherapy and chemotherapy resistance, inhibit the apoptosis of tumor cells, and further promote the malignant progression of tumors via involving in chromatin state maintenance, methylation modification, endogenous competition and transcriptional regulation. It may serve as a valuable tumor marker and therapeutic target.

A two-dimensional liquid chromatography (2D LC) system was developed to separate proteins from rice leaves, which was extracted by phenol method, followed by the analysis with linear trap quadrupole orbitrap mass spectrometry (LTQ/Orbitrap MS). After proteins were extracted with phenol method, the enzymolytic peptides were separated by offline two-dimensional RP-RP system and detected by LTQ/Orbitrap MS, yielding 2712 proteins. Liquid chromatography separation system (1D LC and 2D LC) and protein extraction methods (phenol method, sodium dodecyl sulfate method (SDS method) and trichloroacetic acid/acetone method (TCA/acetone method)) were compared. Proteins identified by 2D LC were 2712, 2415 and 1914 with the above three extraction methods, respectively. The proteins were 2.7-fold, 2.5-fold and 1.9-fold the number of proteins identified by 1D LC respectively. And in terms of 2D LC, the proteins identified by phenol method were 297 and 798 more than SDS method and TCA/acetone method, respectively. Some proteins with extreme properties, such as very acidic or basic protein and high relative molecular mass proteins, were only identified in phenol method. Furthermore, proteins, which were extracted by different extraction methods and separated by 2D LC, were classified according to biological functions. It was found that protein functions by the three extraction methods were complementary. However, phenol method had the most variety of functions. The method provides technological support for rice proteomics and reference for research techniques of other crop proteomics.

A sensitive method was developed for the simultaneous identification of five ustiloxins in the false smut balls of rice by high performance liquid chromatography-linear ion trap/orbitrap high resolution mass spectrometry (HPLC-LTQ/Orbitrap MS). The samples were extracted with deionized water under ultrasonic condition for 10 min, then purified by a strong cation exchange column (PCX). The ustiloxins were separated on an Xselect HSS T3 column (150 mm x 2.1 mm, 3.5 μm) by using 0.1% (v/v) formic acid water solution and methanol as mobile phases with gradient elution at a flow rate of 0.3 mL/min. The full scan range was m/z 200-1 000. The confirmatory analysis of the target compounds was carried out by the accurate mass of quasi-molecular ion, isotope abundance ratio and qualitative fragments. The results showed that the five ustiloxins (A, B, C, D and F) were identified from the false smut balls with mass accuracy less than 1 x 10(-6) (1 ppm) and the absolute values of the deviation of isotope abundance ratio were not more than 3.3%. The product ions were consistent with the theoretical fragment mode. The recoveries were 90% to 105%. This method is accurate and sensitive for the simultaneous identification of the five ustiloxins, which can provide technical means for the research of the ability in toxin producing by Ustilaginodea virens.

An analytical method was developed for the simultaneous determination of 32 pesticides including organophosphorus, organochlorine, pyrethroid and carbamate pesticides in fruits and vegetables using gas chromatography-mass spectrometry (GC-MS). The sample was extracted with acetonitrile, and the organic layer was cleaned up with ENVI-Carb and LC-NH2 cartridges. A large volume of 20 µL purified solution was injected into the GC system using programmable temperature vaporizer (PTV). The mass spectrometric detection was operated with full scan mode. The automated mass spectral deconvolution and identification system (AMDIS) and an isotopic internal standard were used for the qualitative and quantitative determination of the 32 pesticides, respectively. The conditions for PTV-large volume injection were studied. Furthermore, the selectivity and durability of the method were also assessed. Under the optimized conditions, the experimental results showed that all the linearities were good within their test ranges, with correlation coefficients more than 0. 995, and the method detection limits of the pesticides were 2.0-5.0 µg/kg. The spiked recoveries (n=6) at three levels in the 0. 010 - 0. 50 mg/kg using spinach, snap bean and cucumber samples as blank matrices were in the range of 65. 2% - 120. 3% with the relative standard deviations (RSDs) varying from 4. 1% to 22. 3%, showing good accuracy of the method. The advantages of the proposed method include high throughput, high sensitivity, reliability, robustness, and the ability to meet the demand of multi-residue pesticide analysis in fruits and vegetables.

Background and Objective: The invasive tumor front (ITF) refers to cells or invasive nests in the junctional region of a tumor and its host. The ITF contains the most invasive cells of a tumor, and has a high prognostic value in carcinoma. The aim of this study is to investigate the epithelial-mesenchymal transformation phenotype in ITF cells of lung squamous cell carcinoma (SCC), and analyze the relationship between clinicopathological features and clinical outcomes of patients., Methods: Semiquantitative immunohistochemistry was used to examine the expression of epithelial markers (E-cadherin and β-catenin) and mesenchymal marker (vimentin) in 104 lung SCC tumor tissues., Results: A decrease in E-cadherin expression in ITF cells was observed in 56 of 104 (53.8%) tumors from patients. This result was markedly lower than that of non-ITF cells, which eventually developed metastatic tumors and were also associated with death (P=0.04). Vimentin expression was observed in 44 of 104 (42.3%) ITF cells, which was much higher than that of non-ITF cells. The downregulation of E-cadherin and overexpression of vimentin were associated with tumor invasive pattern, lymphatic metastasis, and poor prognosis (P<0.01). The expression of β-catenin was 67.3% (70/104) in ITF cells. Moreover, ITF cells showed more nuclear and plasma-positive cells, which were closely associated with metastasis (P<0.01)., Conclusions: The loss in expression of E-cadherin/β-catenin and overexpression of vimentin in ITF cells may be associated with poor prognosis of lung SCC patients.

Membranes prepared from bovine skin collagen were exposed to 15, 25, 35 KGy gamma-radiation respectively at low temperature. Radiation dose rate of about 22 KGy/h was used. The stability of the membranes was evaluated by measuring resistance of collagen membranes to collagenase digestion. Infrared spectra analyses of collagen films were performed in order to explore possible mechanisms of irradiation modification of collagen membranes. The results revealed that the degree of cross-linking and stability of collagen membranes after gamma-irradiation were improved. The MTT assay and SEM observation of the morphology of L929 mouse fibroblast cells which directly cultured on the collagen membranes were employed to evaluate the cytocompatibility of collagen membranes treated by gamma-ray radiation. In the range of 0 to approximately 25 KGy irradiation dose, no significant difference in cytocompatibility of collagen membranes irradiated by gamma-ray was observed. However, when the irradiation dose was over 25 KGy, the cytocompatibility of collagen membranes was influenced by gamma-radiation to some degree.