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Backgrounds Due to the unexpected side effects of the iodinated contrast agents, novel contrast agents for X-ray computed tomography (CT) imaging are urgently needed. Nanoparticles made by heavy metal elements are often employed, such as gold and bismuth. These nanoparticles have the advantages of long in vivo circulation time and tumor targeted ability. However, due to the long residence time in vivo, these nanoparticles may bring unexpected toxicity and, the preparation methods of these nanoparticles are complicated and time—consuming. Methods In this investigation, a small molecular bismuth chelate using diethylenetriaminepentaacetic acid (DPTA) as the chelating agent was proposed to be an ideal CT contrast agent. Results The preparation method is easy and cost—effective. Moreover, the bismuth agent show better CT imaging for kidney than iohexol in the aspect of improved CT values. Up to 500 µM, the bismuth agent show negligible toxicity to L02 cells and negligible hemolysis. And, the bismuth agent did not induce detectable morphology changes to the main organs of the mice after intravenously repeated administration at a high dose of 250 mg/kg. The pharmacokinetics of the bismuth agent follows the first—order elimination kinetics and, it has a short half—life time of 0.602 h. The rapid clearance from the body promised its excellent biocompatibility. Conclusions This bismuth agent may serve as a potential candidate for developing novel contrast agent for CT imaging in clinical applications.

Glial glutamate transporter 1 (GLT-1) plays a vital role in the induction of brain ischemic tolerance (BIT) by ischemic preconditioning (IPC). However, the mechanism still needs to be further explained. The aim of this study was to investigate whether peroxisome proliferator-activated receptor gamma (PPARγ) participates in regulating GLT-1 during the acquisition of BIT induced by IPC. Initially, cerebral IPC induced BIT and enhanced PPARγ and GLT-1 expression in the CA1 hippocampus in rats. The ratio of nuclear/cytoplasmic PPARγ was also increased. At the same time, the up-regulation of PPARγ expression in astrocytes in the CA1 hippocampus was revealed by double immunofluorescence for PPARγ and glial fibrillary acidic protein. Then, the mechanism by which PPARγ regulates GLT-1 was studied in rat cortical astrocyte-neuron cocultures. We found that IPC [45 min of oxygen glucose deprivation (OGD)] protected neuronal survival after lethal OGD (4 h of OGD), which usually leads to neuronal death. The activation of PPARγ occurred earlier than the up-regulation of GLT-1 in astrocytes after IPC, as determined by western blot and immunofluorescence. Moreover, the preadministration of the PPARγ antagonist T0070907 or PPARγ siRNA significantly attenuated GLT-1 up-regulation and the neuroprotective effects induced by IPC in vitro. Finally, the effect of the PPARγ antagonist on GLT-1 expression and BIT was verified in vivo. We observed that the preadministration of T0070907 by intracerebroventricular injection dose-dependently attenuated the up-regulation of GLT-1 and BIT induced by cerebral IPC in rats. In conclusion, PPARγ participates in regulating GLT-1 during the acquisition of BIT induced by IPC. Cover Image for this issue: doi: 10.1111/jnc.14532. Open Science: This manuscript was awarded with the Open Materials Badge For more information see: https://cos.io/our-services/open-science-badges/.

Objective: We aimed to explore the expression and interplay of NO and iNOS to elucidate their roles in human maxillary sinus mucosa with maxillary sinus fungus ball (MSFB) and chronic rhinosinusitis (CRS).Methods: Fifty-one patients with MSFB, CRS and simple maxillary sinus cyst were included in this study. The NO content of the mucosa of each group was detected by Nitric acid reductase method. The expression of iNOS was tested by immunohistochemistry and Western blott. Spearman correlation analysis was used to analyze the correlation between the expression of iNOS and the occurrence of MSFB and CRS.Results: The results showed that NO and iNOS were highly expressed in the maxillary sinus mucosa of MSFB group, which were significantly different from CRS and control group (PConclusion: NO and iNOS are overexpressed in the maxillary sinus mucosa of MSFB and CRS patients, and the increase in the MSFB patients was better than the CRS. The expressions of NO, iNOS were also correlated with the incidence of MSFB. We thus provide a new indicator to assist the diagnosis of MSFB and its distinction from CRS.

Cancer stem cells (CSCs) play critical roles in cancer, making them important targets for new diagnostic and therapeutic approaches. Since CSCs are heterogeneous and not abundant in tumors, and few specific markers for these cells currently exist, new methods to isolate and characterize them are required. To address this issue, we developed a new label-free methodology to isolate, enrich, and identify CSCs from an heterogeneous tumor cell subpopulation using a cell sorting method (sedimentation field flow fractionation, SdFFF) and a biosensor as a detector. Enrichment was optimized using an original protocol and U87-MG glioblastoma cells cultured in a normal (N) or defined (D) medium (± fetal bovine serum, FBS) under normoxic (N, pO2 = 20%) or hypoxic (H, pO2 < 2%) conditions to obtain four cell populations: NN, NH, DN, and DH. After elution of CSCs via SdFFF using the hyperlayer mode (inertial elution mode for micrometer-sized species), we isolated eight subpopulations with distinct CSC contents based on phenotypical and functional properties, ranging from NN F1 with a lower CSC content to DH F3 with a higher CSC content. Reflecting biological differences, the intrinsic intracellular dielectric permittivity increased from NN to DH conditions. The largest difference in electromagnetic signature was observed between NN F1 and DH F3, in which the CSC content was lowest and highest, respectively. The results demonstrate that microwave dielectric spectroscopy can be used to reliably and efficiently distinguish stem cell characteristics. This new instrumental and methodological approach is an important innovation that allows both enrichment and detection of CSCs, opening the door to novel diagnostic and therapeutic approaches.

In this work, we report a colorimetric method for detection of ascorbic acid based on growth of silver nanoparticles by a simple and green photo-catalytic route. This route contains two steps, photo-synthesis of silver nanoclusters (NCs) with papain under UV irradiation, and catalytic growth of silver nanoparticles (NPs) in the presence of ascorbic acid. The produced silver NCs at the first step is excellent catalyzer that could quickly catalyze the growth of silver NPs by Ag+ and ascorbic acid in 1 min at room temperature. And thus, in the second step, the color of the mixture changed from colorless to yellow and a strong absorption band near 420 nm could be found in their absorption spectra owing to localized surface plasmon resonance (LSPR) of produced silver NPs. We found that the absorbance changes at 420 nm have a good relationship with ascorbic acid concentration, and established a spectrophotometric method for the sensing of ascorbic acid in the range from 0.25 to 50.0 μM, with a limit of detection (LOD) as low as 79.2 nM. We also established a colorimetric assay of ascorbic acid by analyzing the yellow value (Y%) of the silver NPs photographs using cyan, magenta and yellow (CMY) color mode. The lowest detection concentration of ascorbic acid for colorimetric assay by the photographs could be estimated to ∼1 μM. Moreover, the method for ascorbic acid detection also has high selectivity. Potential interferes, such as glucose, dopamine, uric acid and cysteine will not affect the detection of ascorbic acid.

An aqueous dispersion was prepared by attaching positively charged gold nanoparticles to the surface of poly-sodium-p-styrenesulfonate-modified Fe3O4 nanoparticles. The Fe3O4@positively charged gold nanoparticles offer high monodispersion, stability against aggregation, and high magnetization with uniform size. The Fe3O4@positively charged gold nanoparticles were efficient and recyclable catalysts due to the formation of a positively charged gold layer on the surface of Fe3O4 nanoparticles and were stable in aqueous solution for over forty-eight hours and hence may have a broad range of applications.

In order to researching the microstructure of bioceramic coating on the surface medical titanium alloy (Ti–6Al–4V), the gradient bioceramic coatings are fabricated by wide-band laser cladding. The influence of multiple rare earths oxide La2O3 and CeO2 on microstructure of bioceramic coating were studied. The experimental results demonstrated that mixed La2O3 and CeO2 have an effect on forming-ability of HA\β-TCP in bioceramic coating and also refined the grain of bioceramic coatings. The largest amount of HA\β-TCP is presented among all the groups when the contents of La2O3 and CeO2 are 0.6wt.%, 0.4 wt.%, respectively.

Separating fluorite from quartz and calcite by forth flotation can be both in weak-acidized (pH 6.0) condition and weak alkali (pH 9.0) condition. The experiment results have shown that ZnSO4can decrease the depression that water glass works on the fluorite, and acidized water glass has a selective inhibition on the silicate minerals. The close flowsheet protocolled in the experiment can obtain the content of CaF2, SiO2in the final concentrate are 97.89%, 0.91% respectively, and the recovery rate of CaF2is 84.18%, which is reach the requirement of the plant.

To improve bioactivity of gradient bioceramic coating, the coating with two kinds of rare earth oxide was produced by wide band laser cladding technique. As the experimental results, whichadded0.6wt.% La2O3 fixedly, and increased the addition amount of the CeO2, when the addition of CeO2fulfill 0.4wt.%, the amount of HA-β-TCP is the largest in this experiment. Soaking the specimens in SBF for 14 days, the coating blended 0.6wt% La2O3 and 0.4wt% CeO2, then a great quantity of Ca-P white particles can be found on coating, which confirmation this bioceramic coating is of best bioactivity.

Monitoring of plasma methotrexate (MTX) concentrations allows for therapeutic adjustments in treating childhood acute lymphoblastic leukemia (ALL) or non-Hodgkin lymphoma (NHL) with high-dose MTX (HDMTX). We tested the hypothesis that assessment of creatinine clearance (CrCl) and/or serum Cr may be a suitable means of monitoring plasma MTX concentrations. All children in the study had ALL or NHL, were in complete remission, and received HDMTX (3 or 5 g/m2)+leucovorin. Plasma MTX concentrations were measured at 24, 48, and 96 h. CrCl was determined at 24 and 48 h. Correlations between 24- and 48-h plasma MTX concentrations and CrCl and serum Cr concentrations were determined. CrCl and serum Cr concentrations were compared over time between children who had delayed and non-delayed MTX elimination. A total of 105 children were included. There were significant negative correlations between CrCl at 24 and 48 h and plasma MTX concentrations at 24 (both p

A functional composite of Fe3O4@SiO2-Au was prepared and used for latent fingerprint detection. Material characterization results confirmed the successful fabrication of the Fe3O4@SiO2-Au composite. In latent fingerprint detection, the Fe3O4@SiO2-Au composite provides a better performance than commercial copper powder and also gold nanoparticles. More importantly, the Fe3O4@SiO2-Au composite can be used in both powder and suspension forms, and also for common surfaces including glass, polyethylene bags, and paper. The favorable pH range (2.0–5.0) for the compositein finger marks detection is much wider than that of the traditional multi-metal deposition method (pH ranging from 2.0 to 3.0). The mechanism for the Fe3O4@SiO2-Au composite in fingerprint detection was explored and discussed. This study provides a favorable choice for a one-step deposition method for latent fingerprint detection.

To improve bonding strength between Ti alloy and bioceramic coating and to eliminate thermal stress during laser cladding, gradient bioceramic coating materials is designed. The bioceramic coating is fabricated by wide band laser cladding technique. And the effect of adding single and multiple rare earth oxide on microstructure is investigated. The samples are soaked with SBF for 14 days, the experimental results indicate that when the content of single rare earth oxide is 0.6wt.%Y2O3, a large number of bioactivity phase and chrysanthemum shape microstructure can be observed. When the content of single rare earth oxide is 0.2wt.%Sm2O3, a lot of bioactivity phase and coral reef shape microstructure can be observed. When the content of multiple rare earth oxide is 0.3wt.%Sm2O3 and 0.4wt.%Y2O3, a large amount of bioactivity phase and more homogeneous and dense spherical particles can be observed on coating, which demonstrates the microstructure is of better bioactivity.

The Fe3O4 -core and Ag- shell (Fe3O4@Ag nanoeggs) were prepared through the encapsulation of 3aminopropyltriethoxysilane-coated magnetite nanoparticle in nano-Ag shell by a simple chemically controlled procedure. The Fe3O4@Ag nanoeggs were characterized by scanning electron microscopy, transmission electron microscopy, UV-vis spectrum and superconducting quantum interference device magnetometer, respectively. A detailed analysis is provided of how the hydrolysis and condensation of 3-aminopropyltriethoxysilane and the pH value are vital in fabricating the Fe3O4@Ag nanoeggs. The prepared Fe3O4@Ag nanoeggs possessed uniform size, improved monodispersity, stability against aggregation and high magnetization, which were utilized for the detection of latent fingerprints deposited onto different surfaces. The experimental results showed that the latent fingerprints developed with the Fe3O4@Ag nanoeggs powders exhibited excellent ridge details with minimal background staining.

Six silver colloids were prepared by the reduction of silver nitrate with different amounts of sodium citrate. The obtained silver colloids were characterised by UV–vis spectroscopy, transmission electron microscopy and zeta potential measurements. The surface-enhanced Raman scattering (SERS) activities of these silver colloids were investigated using crystal violet (CV) as a SERS probe. Based on density functional theory (DFT) calculations at the level of B3LYP, the Raman spectra and the optimised geometry of CV were analysed. The results show that the sodium citrate content strongly influences the sizes, zeta potentials and SERS activities of the silver colloids. As the sodium citrate content increases in the preparation of silver colloids, the mean diameters of the silver nanoparticles decrease. The most intense SERS of CV on the silver colloids is obtained when 3 mL of 1% sodium citrate is used. CV has D3 point group symmetry, and the Raman vibrational modes belong to A1 or E irreducible representations. The non-totally symmetric vibrational modes E are selectively enhanced in the SERS of CV through a Herzberg–Teller vibronic coupling mechanism, indicating a considerable charge transfer between CV and the silver nanoparticles.

Our previous study has proved that the up-regulation of glial glutamate transporter 1 (GLT-1) played an important role in the acquisition of brain ischemic tolerance after cerebral ischemic preconditioning (CIP) in rats. However, little is known about the mechanism involved in the up-regulation of GLT-1 in the process. The present study investigates whether p38 MAPK, ERK1/2, and/or JNK participates in the up-regulation of GLT-1 during the induction of brain ischemic tolerance by CIP. It was found that CIP significantly enhanced the expression of p-p38 MAPK without altering p-ERK1/2 and p-JNK expression in the CA1 hippocampus. Inhibition of p38 MAPK function by its selective inhibitor SB203580 or knockdown p38 MAPK expression by its antisense oligodeoxynucleotides (AS-ODNs) suppressed the induction of brain ischemic tolerance. Furthermore, p38 MAPK was activated earlier than the up-regulation of GLT-1 in the CA1 hippocampus after CIP. Meanwhile, the expression of p-p38 MAPK by astrocytes was increased, and p38 MAPK AS-ODNs dose-dependently inhibited the up-regulation of GLT-1 after CIP. Taken together, it could be concluded that p38 MAPK participates in the mediation of GLT-1 up-regulation during the induction of brain ischemic tolerance after CIP.

A label-free amperometric immunosensor for the detection of methamphetamine was developed. The prussian blue deposited/l-cystine-modified electrode was covered with nano-Au/(3-mercaptorpropyl) trime-thoxysilane film. Then, the nano-Au was used for the immunosensor platform to capture a large amount of anti-methamphetamine. PB exhibited excellent electrocatalytical properties toward the reduction of H2O2 at low overpotentia to amplify the amperometric signal, which enhanced the sensitivity of the immunosensor. The active sites of PB could be shielded and the access of H2O2 from solution to the electrode might be partially blocked after the completion of immunoassay, led to a linear decrease in the response current of the electrode over the range from 1.0×10(-8) to 5.0×10(-6) mol L(-1)of MA. The obtained immunosensor displayed excellent catalytic reduction toward H2O2 due to high activity and selectivity of PB. The influence of relevant experimental variables, including the construction of immunosensor platform, the amount of MPS and the time of immunoaction, was examined and optimized.

This paper presents an improved design of resonant biosensor, dedicated to dielectric analysis on biological cells at microwave frequencies. Such sensor uses the capability of microwaves to penetrate inside biological cells in order to interact with their intracellular content. Hence, individual dielectric properties of the cell cytoplasm can be known and then used as a signature of the cell pathological state (living or dead, malignant or safe...). In this paper is introduced a continuously tunable frequency sensor prototype, able to perform an accurate dielectric analysis over at least a 1GHz bandwidth while keeping enough sensitivity to detect and analyze a single cell. As a proof of concept, permittivity measurements have been led on calibrated size polystyrene beads: achieved results show good agreement with expected permittivity values. Finally experiments on Glioblastoma cells will be presented.

Quinoxaline 1,4-dioxides (QdNOs) derivatives, the potent synthetic antibacterial group used in food-producing animals, are assumed to have pro-oxidant properties. However, how oxidative stress mediated their adrenal toxicity is far from clear. The aim of this study was to assess the ability of three QdNOs, i.e. olaquindox (OLA), mequindox (MEQ), and cyadox (CYA), to produce reactive oxygen species (ROS) and oxidative cell damage in porcine adrenocortical cells. Multiple approaches such as cell activity assay, biochemical detectation, flow cytometry and fluorescent were used to study the integrated role of ROS homeostasis, mitochondrial redox metabolism and cell apoptosis as well as chemical stability of these drugs. The results showed that OLA and MEQ treatment evoked a significant dose and time-dependent cell damage in adrenocortical cells, well CYA displayed much less toxicity. As for the intracellular ROS production, OLA irritated a persistent and utmost release of ROS while MEQ made a similar but weaker reaction. CYA, however, had a short and unstable release of intracellular ROS. On the other hand, quinoxalinine-2-carboxylie acid (QCA), one of the metabolites of OLA and MEQ, did not cause any significant production of ROS and showed relatively lower toxicity than its parents. Moreover, an imbalance in the redox metabolism and mitochondrial membrane damage has been implicated in adrenal toxicity of QdNOs. ROS scavengers partially reversed QdNOs-induced mitochondrial damage, indicating that mitochondria may be a major target and critical for ROS-mediated cell death. In a word, these results suggested that ROS is a key mediator of QdNOs-induced cell death via mitochondria-dependent pathway in adrenocortical cells. The results provide a mechanism approach in understanding the characterize of adrenal damage caused by QdNOs in vitro, which would in turn, help in designing the appropriate therapeutic strategies of these kind of feed additives.