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The evolution process of Ag plays a dominant role and presents an obvious effect on promoting the ordering transition of FePt NPs.

Nanomaterials and nanotechnology have been widely used in various fields, such as materials, chemical engineering, optics, and other disciplines. In this paper, gold nanoparticles are prepared by the hydrothermal method and treated with polypyrrole coating (PPy-GNPs). Then, the anti-HER2 protein was conjugated to polypyrrole coated gold nanoparticles, and the nanomaterials are named anti-HER2-PPy@GNPs (anti-PPy@GNPs). Their diameter is about 80–90 nm, and they show a strong absorption peak in the near-infrared band, especially under 808 nm laser irradiation. In the MTT test experiment, anti-HER2-PPy@GNPs show a significant inhibitory effect on the SKOV-3 cell. Fluorescent cytoskeletal analysis of SKOV-3 cells and atomic force microscopy (AFM) of the mechanical characteristics of the cell surface revealed that the cell micro-structure, adhesion, and Young's modulus of anti-HER2-PPy@GNPs have changed under the near-infrared illumination. These results indicate anti-HER2-PPy@GNPs has an inhibitory effect on SKOV-3 cells. AFM detects the mechanical characteristics of SKOV-3 cells. Compared with the control group, Young's modulus is increased 52.7%, while the adhesion force is decreased 14.47%.

In order to rapidly determine the concentration of recombinant Ganoderma lucidum immunomodulatory protein-8 (rLZ-8) at a lower cost, a peptide-antigen-antibody sandwich ELISA method was developed based on a dodecapeptide LTPHKHHKHLHA with higher affinity for rLZ-8, which was identified from phage display after four rounds of screening. The binding mode between rLZ-8 and the peptide ligand was further simulated and revealed by molecular docking. Standard addition and repetitive testing were carried out to evaluate the accuracy, reproducibility and feasibility of the developed ELISA detection method. The method based on this peptide ligand was then successfully applied in the quantitative determination of rLZ-8 concentrations in fermentation broth. In summary, the peptide-antigen-antibody sandwich ELISA method developed here could be conveniently applied in the detection of rLZ-8 during fermentation and might provide new insights for the detection of other specific proteins.

Antibody pairing is a difficult step in developing all immune-sandwich assay for antigen detection. Urinary bladder cancer (UBC) antigen is a typical bladder cancer biomarker for the early diagnosis of bladder cancer. Based on peptide-antibody pairing, a surface-enhanced Raman scattering platform for the ultrasensitive detection of UBC is presented. The phage display tech was used to screen and obtain a 12-peptide ligand against UBC (KD = 4.84 × 10

Photothermal therapy is a treatment method which used a material with a high conversion efficiency of field or biological synthetic material, using target recognition technology gathered near the cancer tissues after injected into human bodies, with near-infrared convert light energy into heat energy to kill cancer. Here reported the biocompatible use of gold nanorods(GRNs) as probes for cancer targeting in vitro. More specifically, this paper demonstrated a progressive synthesis approach in fabricating water-dispersible gold nanorods. These nanorods were prepared by replacing cetyltrimethylammonium bromide with a mixture of 15-polypeptide(15P) molecules, such that a variety of cell viability assays did not reveal any signals of toxicity in the treated cells. The samples size was estimated to be 70-80 nm; Dynamic light scattering reveals that the cores of the gold nanorods are protected from the outside environment by the 15-polypeptide. Photothermal treatment indicated that 15P-GNRs can stain tumor growth and devoted the pivotal steps in promoting of the use of ternary GNRs as a tumor targeting, more importantly, these results suggest that 15P-GNRs can serve as biocompatible synthetic material and multimodal platform for various bio-applications and the micelle-encapsulated nanoparticles formulation was able to target the tumor site directly. On the other hand, Photothermal therapy has great effect in killing cancer cell with near-infrared.

C. testosteroni is a research topic that can degrade steroid hormones into water and carbon dioxide through a series of enzymes in the body. Short-chain dehydrogenase (SDR) are a class of NAD (P) H-dependent oxidoreductases in C. testosteroni. Its main function is catalyzing the redox of the hydroxyl/ketone group of the hormone. In this paper, a SDR gene(SDRx) is cloned from C. testosteroni ATCC11996 and expressed. The polyclonal antibody was prepared and the SDRx gene knocked out by homologous recombination. Wild type and mutant C. testosteroni induced by testosterone, estradiol, estrone and estriol. The growth curves of the bacteria were measured by spectrophotometer. ELISA established the expression of SDRx protein, and high-performance liquid chromatography(HPLC) detected the contents of various hormones. The results show that the growth of wild type was faster than mutant type induced by testosterone. The concentration of SDRx is 0.318 mg/ml under testosterone induction. It has a great change in steroid hormones residue in culture medium measured by HPLC: Testosterone residue in the mutant type group was 42.4 % more than the wild type in culture medium. The same thing happens with induced by estrone. In summary, this SDRx gene involved in the degradation of testosterone and estradiol, and effects the growth of C. testosteroni.

Docetaxel could inhibit the proliferation of tumor cells by targeting microtubules. The extension of cellular microtubules plays an important role in the invasion and metastasis of tumor cells. This paper aims to study the distribution and mechanical properties of cytoskeletal proteins with low concentration of docetaxel. MTT assay was used to detect the minimum drug activity concentration of docetaxel on SKOV-3 cells, fluorescence staining was used to analyze the distribution of cytoskeleton proteins, scanning electron microscopy(SEM) was used to observe the morphology of single cells, and atomic force microscopy(AFM) was used to determine the microstructure and mechanical properties of cells. The results showed that the IC10 of docetaxel was 1 ng/ml. Docetaxel can effectively inhibit the formation of cell pseudopodia, hinder the indirectness between cells, reduce the cell extension area, and make the cells malformed. In addition, when AFM analyzes the effects of drugs on cell microstructure and mechanical properties, the average cell surface roughness and cell height are positively correlated with the concentration of docetaxel. Especially when the concentration was 100 ng/ml, the adhesion decreased by 37.04% and Young's modulus increased by 1.57 times compared with the control group. This may be because docetaxel leads to microtubule remodeling and membrane protein aggregation, which affects cell microstructure and increases cell strength, leading to significant changes in the mechanical properties of ovarian cells. This is of great significance to the study of the formation mechanism of tumor cell invasion and migration activities mediated by actin.

Conductive atomic force indentation (CAFI) was proposed to study the self‐repair behaviour of the neuronal cell membrane here. CAFI was used to detect the changes of membrane potentials by performing the mechanical indentation on neurons with a conductive atomic force microscope. In the experiment, a special insulation treatment was made on the conductive probe, which turned out to be a conductive nanoelectrode, to implement the CAFI function. The mechanical properties of the neuronal cell membrane surface were tested and the membrane potential changes of neurons cultured in vitro were detected. The self‐repair behaviour of the neuronal cell membrane after being punctured was investigated. The experiment results show that CAFI provides a new way for the study of self‐repair behaviours of neuronal cell membranes and mechanical and electrical properties of living cells.

Dexamethasone (DEX) is associated with many inflammation and metabolic diseases. We analyzed the effects of DEX on the expression of estrogen metabolism enzyme 17β-HSD1 at the optic nerve. Rats were treated with different concentrations of intraperitoneal DEX. Western Blot analysis showed that 17β-HSD protein was expressed in the optic nerve tissue. The enzyme was detected by immunohistochemistry on the terminal foot of Muller cells from the ganglion cell layer of rat retina. ELISA analysis showed that the 17β-HSD1 protein expression of DEX-treated group is 2.4 fold comparing to the control group. The results indicated that DMXS sodium phosphate might modulate the expression of 17β-HSD1 protein in optic tissue. This study sheds light on understanding of the relationship among DEX, 17β-HSD presence and distribution of visual neural systems. At the same time, DEX treatment affects the athletic ability and memory of the animals. Compared with the control group, the experimental group showed slow response to stimulation, inertia, depression, cowardice and lack of appetite. The results of ethology experiments showed that all the parameters decreased by 15–30%.

Renal tubular cell injury by exposure to high glucose (HG) stimulation mainly accounts for diabetic nephropathy (DN). To understand the mechanism of injury by HG, quantitative characterization has commonly focused on the cells that are already impaired, which ignores the signals for the process of being injured. In this study, the architecture and morphology of HK-2 cells were observed dynamically by multiple imaging methods. AFM (atomic force microscopy)-based single-cell force spectroscopy was employed to investigate the dynamic mechanics quantitatively. The results showed that the Young's modulus increased continuously from 2.44 kPa up to 4.15 kPa for the whole period of injury by HG, while the surface adhesion decreased from 2.43 nN to 1.63 nN between 12 h and 72 h. In addition, the actin filaments of HK-2 cells exposed to HG depolymerized and then nucleated with increasing Young's modulus. The absence of cell pseudopodia coincided with the reduced cell adhesion, strongly suggesting close relationships between the cell architecture, morphology and mechanical properties. Furthermore, the stages of cell reactions were identified and assessed. Overall, the dynamic mechanics of the cells facilitate the identification of injured cells and the assessment of the degree of injury for accurate diagnoses and treatments.

The electronic structure and photophysical properties of five iridium(III) complexes have been studied using the density functional theory (DFT) and time-dependent density functional theory (TDDFT) methods. The influence of different conjugated structures on their photophysical properties has been explored. Ionization potentials, electron affinities and reorganization energy have also been obtained to evaluate the charge transfer and balance properties between hole and electron. The lowest energy emissions from the CAM-B3LYP level for these complexes are localized at 472, 503, 523, 635 and 699 nm, respectively. The theoretical investigation would be useful to design potential phosphorescent materials for application in the organic light-emitting diodes.

High photoluminescent (PL) nitrogen-doped carbon dots (N-CDs) have been synthesized using ferric ammonium citrate (FAC) and urea as raw materials by simple one-pot hydrothermal process. The N-CDs possess bright blue fluorescence (centred at 450 nm; 36.2% quantum yield) and green fluorescence (centred at 530 nm; 47.6% quantum yield) only by adjusting the excitation wavelength from 310 nm to 510 nm. The N-CDs exhibited high N content of 32.81 wt%, low cytotoxicity, and good PL stability at different pH values, ion strengths and temperature, respectively. As-prepared N-CDs were explored for cell imaging with great biocompatibility. The remarkable properties of N-CDs indicated their potential toward sensing and biological applications.

Nanotechnology and its application are widely used in the field of life, human exploration of life science has entered the nano level, which is of great significance for exploring the essence of cellular life. This paper explores the changes in the mechanical characteristics of tumor cells after the photothermal effect of nanomaterials. The experiments used AFM and SEM to measure and observe SKOV-3 cells before and after the treatment. It was found that the cell height, morphology, cell adhesion, and Young’s modulus had significantly changed. In the PPy-GNPs+Laser group, the adhesion force value was 3.57±1.25 nN, and Young’s modulus was 27.4±2.47 kPa. From the data, a 53.9% increase in Yong’s modulus of laser test PPy-GNPs as compared with the control group. It shows that the photothermal effect of nanoparticles has an important effect on the changes of cell ultrastructure, which has important significance for explaining the changes of cell physiological functions from the perspective of cell mechanics.

The results of previous studies have been contradictory in terms of the efficacy of statin treatment in preventing contrast-induced acute kidney injury (CI-AKI) and clinical adverse events (AEs). This meta-analysis was undertaken to assess the role of short-term statin treatment in the prevention of CI-AKI and clinical AEs. We searched the Cochrane Library, EMBASE, and PubMed databases for randomized controlled trials (RCTs) with the development of CI-AKI as a primary outcome. Secondary outcomes were the post-procedural serum creatinine (SCr) level, estimated glomerular filtration rate (eGFR), and development of AEs. We also performed prespecified subgroup analyses. A total of 21 RCTs involving 7746 patients were included. Short-term statin treatment significantly reduced the risk of CI-AKI [risk ratio (RR) 0.57; 95 % confident interval (CI) 0.47–0.69; p

The study of the electrical coupling properties of living cells and materials plays an important role in tissue engineering and clinical applications. The electrical coupling between living cells and substrates directly affects the growth, secretion and death of cells, as well as the measurement accuracy of electrophysiological parameters. In this work, the point contact model of the electrical coupling of cells and substrates is studied. It was found that the sealing impedance and effective contact area were the most important parameters affecting the electrical coupling. Moreover, the structure of nano-scale groove was fabricated by direct laser interference patterning (DLIP), and cylindrical arrays were fabricated on resist films after exposed to electron beam lithography (EBL). The two nanostructures were used as the substrates in vitro culture. The electrical coupling properties between living cells and structural substrates were discussed subsequently. In addition, the impedance spectrum of living cells at various frequencies, the relationship between the living cell number and impedance, and the impedance of living cells at different growth periods were measured. Furthermore, the multidimensional impedance information of living cells was obtained, and the impedance deviations between the two structure arrays were analyzed to evaluate the electrical coupling properties between the living cells and substrates. The proposed multidimensional impedance analysis method provides a way for studying the electrical coupling properties of nano-structured substrates and living cells.

Procalcitonin (PCT) is the precursor of calcitonin related to the severity of human bacterial infection. We made a test strip by coupling anti-PCT to quantum dot, in order to develop a highly sensitive and convenient PCT testing product. The anti-PCT titer had reached 10⁷ because of the stability by coupling anti-PCT with quantum dot. The detecting linear range of the experiment was 0.15 to 120 μg/L, the sensitivity was 0.007 μg/L, the recovery range was 91% to 113%, and the intra- and inter-assay coefficient of variation was less than 8%. Comparing the homemade fluorescence-detected test strip with PCT ELISA kit on sale, we got accurate results which could mostly accomplish the test of clinical samples.降钙素原 (Procalcitonin，PCT) 是降钙素的前体物质，与人体细菌感染情况严重程度相关。通过PCT抗体与量子点偶联，自制试纸条，开发一种高灵敏度、快速便捷的PCT 检测产品，对其初步应用。PCT 单抗效价达10⁷，PCT 蛋白与量子点偶联，具有较好稳定性。试纸条线性检测范围0.15–120 μg/L，灵敏度0.007 μg/L，回收率范围91%–113%，批内批间变异系数小于8%。自制的荧光检测试纸条与市场上已有的降钙素原ELISA 试剂盒进行比对，检测结果良好，基本能够完成临床样品的检测。.

3,17β-Hydroxysteroid dehydrogenases (3,17β-HSDs) are found in all forms of life which catalyze the 3-position and 17-position reduction/oxidation of steroids. Comamonas testosteroni (C. testosteroni) ATCC11996 is a gram-negative bacterium which can use steroids as carbon and energy source. 3,17β-HSD is an enzyme which is involved in the complete oxidative degradation of the steroid skeleton, induced in the presence of these compounds in the culture medium. Cyclizing RT-PCR (cRT-PCR) was used to investigate the transcription start site (TSS) and promoter of 3,17β-HSD gene. To prove that 3,17β-HSD is involved in the metabolic pathway of steroid compounds, we prepared a 3,17β-HSD gene knock-out mutant and a mutant of C. testosteroni in which 3,17β-HSD was expressed at high level. The results indicate that 3,17β-HSD gene expression was induced by testosterone, but not by estradiol and cholesterol. Compared to the wild type C. testosteroni, degradation ability of testosterone and cholesterol was almost lost, and degradation of estradiol was decreased in the 3,17β-HSD knock-out mutant. Meanwhile degradation of testosterone, cholesterol was obviously increased in the 3,17β-HSD high expression mutant. Furthermore, the growths in the medium with testosterone, cholesterol or estradiol were impaired in 3,17β-HSD knock-out mutant. The results showed that in addition to testosterone and estradiol, 3,17β-HSD might be also involved in cholesterol metabolism. The location of the TSS and promoter of the 3,17β-HSD gene were found in this work.

In this work, we synthesized the polypyrrole(PPy) modified gold nanoparticles and demonstrated their negligible cytotoxicity in vitro. These nanoparticles have also been demonstrated to efficiently ablate different kinds of tumor cells in vitro under the irradiation of the near-infrared laser. When the PPy modified gold nanoparticles were conjugated with the tumor-targeted molecule of 15P(sequence: SHSWHWLPNLRHYAS), these conjugates displayed hyperthermia effects on the human ovarian cancer cell line SK-OV-3 cells in vitro under the irradiation of near-infrared laser, showing great tumor-targeted treatment efficiency. To determine the potential hyperthermia effect of PPy modified gold nanoparticles or 15P-conjugate on tumor cells in vivo, the SK-OV-3 cells were used to induce the subcutaneous tumor-bearing nude mice. The significant inhibition effects of near-infrared laser mediated PPy modified gold nanoparticles or 15P-conjugate on the tumor growth were observed. These composite results suggest that the 15P-conjugated PPy modified gold nanoparticles exhibit great biocompatibility, particularly tumor-targeted effect and the effective photothermal ablation of tumor cells, which warrants the potential therapeutic value of this conjugate for further application to the in vivo localized tumor therapy.

By simply running the reactions under air and solvent-free conditions using catalytic amounts of manganese dioxide, a practical and efficient N-alkylation method for a variety of sulfonamides and amines using alcohols as green alkylating reagents was developed.

The thermodynamically unfavorable anaerobic dehydrogenative alcohol activation to aldehydes and hydridometal species is found to be the bottleneck in metal-catalyzed N-alkylations due to a general and unnoticed catalyst deactivation by amines/amides. Thus, different from the anaerobic dehydrogenation process in borrowing hydrogen or hydrogen autotransfer reactions that require noble metal complexes or addition of capricious ligands for catalyst activation, the water-producing, exothermic, metal-catalyzed aerobic alcohol oxidation is thermodynamically more favorable and the most effective and advantageous aldehyde generation protocol. This leads to a general and advantageous air-promoted metal-catalyzed aerobic N-alkylation methodology that effectively uses many simpler, less expensive, more available, and ligand-free metal catalysts that were inactive under typical anaerobic borrowing hydrogen conditions, avoiding the use of preformed metal complexes and activating ligands and the exclusive requirement of inert atmosphere protection. This aerobic method is quite general in substrate scope and tolerates various amides, amines, and alcohols, revealing its potentially broad utilities and interests in academy and industry. In contrast to the commonly accepted borrowing hydrogen mechanism, based on a thorough mechanistic study and supported by the related literature background, a new mechanism analogous to the relay race game that has never been proposed in metal-catalyzed N-alkylation reactions is presented.

Microwave irradiation was found to promote tetrabutylammonium fluoride catalyzed nucleophilic aromatic substitution of aryl fluorides and arylthiotrimethylsilanes, affording high yields of unsymmetrical diaryl thioethers efficiently under mild, transition-metal- and base-free conditions. Microwave showed unusual improvement on the reaction in not only the conditions and reaction rate, but also in selectivity and substrate scope.

We expressed 17-hydroxysteroid dehydrogenase10 (17β-hsd10) recombinant protein, prepared anti-17β- hsd10 polyclonal antibodies and established sandwich enzyme linked immunosorbent assay (ELISA) test for detection of 17β-hsd10. RT-PCR was used to get the gene of 17β-hsd10 of mouse liver, and a prokaryotic protein expression system pET 15b-17β-hsd10/Escherichia coli BL21 (DE3) which induced with isopropyl-1-thio-β-galactopyranoside (IPTG) for recombinant protein expression was constructed subsequently. The target protein purified using His-Binding-resin column was used to immunize BALB/c mice and rabbits, serum total IgGs from immunized animals were purified by ammonium sulfate precipitation method. We established a Double-antibody Sandwich enzyme linked immunosorbent assay about 17β-hsd10 using the two antibodies we prepared. We got the concentration of 1.5 mg/mL of 17β-hsd10 protein with molecular weight of 29.5 kDa, and polyclonal antibodies from mouse and rabbit with the tite 1.25 x 10(4) and 2.5 x 10(4) respectively. The concentration of 0.1 g/mL of 17β-hsd10 can be detected by the Double-antibody Sandwich ELISA we established, and the assay was sensitive and specific. It can be widely used in clinical and experimental study.

The electrogenerated chemiluminescence (ECL) behavior of N-(4-aminobutyl)-N-ethylisoluminol (ABEI) was studied and it was found that ABEI could produce emission light when oxidized at a +1.0 V (vs. Ag/AgCl) potential in alkaline solution. The addition of H2O2 markedly improved the ECL sensitivity. The pH value of the solution as well as the H2O2 concentration and working potential all have influences on the ECL response. Under optimal conditions, ABEI can be detected in the range 1.3 x 10(-6)-6.5 x 10(-12) mol L(-1). A detection limit of 2.2 x 10(-12) mol L(-1) for ABEI was obtained at a signal-to-noise ratio of 3. ABEI was then used as a marker to label a known sequence oligonucleotide, which was used as a DNA probe for identifying a target ssDNA immobilized on a PPy modified electrode based on a specific hybridization reaction. The hybridization events were evaluated by the ECL measurements. The results showed that only a complementary sequence could form a double-stranded DNA with the DNA probe and give a strong ECL response. A three-base mismatch sequence and non-complementary sequence have no response. The intensity of the ECL was linearly related to the concentration of the complementary sequence in the range 9.6 x 10(-11)-9.6 x 10(-8) mol L(-1), the detection limit was 3.0 x 10(-11) mol L(-1).

Ordered hexagonal mesoporous aluminosilicates with lower Si/Al ratio below 5 have been successfully synthesized via the co-assembly of preformed aluminosilicate precursors with Gemini surfactant [C12H25N+(CH3)2(CH2)6N+(CH3)2C12H25] x 2Br(-) as the template. Powder X-ray diffraction, transmission electron microscopy, scanning electron microscopy, N2 adsorption-desorption isotherm measurements, Fourier transform infrared spectroscopy, 27Al nuclear magnetic resonance, thermogravimetric analysis, and temperature-programmed desorption of cyclohexylamine are employed to characterize the resulting samples. The phenol alkylation reaction is carried out to evaluate their catalytic performances. These studies indicate that the sample with a low Si/Al ratio of 3 still retains a highly ordered hexagonal mesoporous structure. And it also possesses the highest acidity of 0.96 mmol among the samples with lower Si/Al ratios below 5 due to its higher specific surface area together with more content of tetrahedrally coordinated Al in the framework. The catalytic tests confirm that the acidity of the samples plays a key role in determining their catalytic performances.

Component-based development is widely used in large-scale software systems, which is focused on modularization and reusability. Each component has several related interfaces, which clearly describe the function, behavior and other relevant information. In addition, component interface also defines communications with other modules. Thus the interface defines all information of the component. The failure of the interface could cause serious problems for the whole system. Therefore, the component interface testing is an essential part of the component development. In this paper, a XML-based component interface testing method is proposed in a virtual experiment platform. The virtual experiment is applied to visualize material property data. The results show its efficiency and flexibility.

By simply running the reactions under air and solvent-free conditions using catalytic amounts of manganese dioxide, a practical and efficient N-alkylation method for a variety of sulfonamides and amines using alcohols as green alkylating reagents was developed.

The reaction allows convenient, efficient and environmentally friendly access to a wide range of secondary amines, amides, and sulfonamides.

Optimized conditions are elaborated for each type of substrates to afford a broad spectrum of title compounds including fluoro derivatives with biological significance.

This paper presents TP-PB algorithm. It applies two phases association rule mining one based partition and Bitset for massive remote sensing images data. Firstly, this algorithm divides massive database into several independent blocks logically. Boolean values are stored in the compressed BitSet in each of block. It generates frequent itemsets by Bitset logical AND operation replaces database scans for each of block. Then it unifies the frequent itemsets and generates global candidate itemsets for the whole data. At last it calculates the min-support of these global candidate itemsets and generates global frequent itemsets for the whole data. By dividing the massive data into a number of blocks, it enhance generic application of algorithm ; Besides it increases algorithm efficiency that database scans is replaced by Bitset logical AND operation in each of block, especially for massive remote sensing image data. And the algorithm has been applied to remote sensing images mining association rules.