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This study aimed to investigate the characteristics and contribution of dissolved organic matter (DOM) components released from agricultural waste to water and to control the exogenous input of DOM in the water environment. The EEMs-PARAFAC (three-dimensional fluorescence-parallel factor) method was used to analyse the grass surrounding Anfeng Pond. The extracts of stems, rice straws, and fallen leaves were used to extract DOM in the agricultural waste for analysis. The results showed that three components were separated from the grass stems, rice straws, and leaves, which were C1-type tryptophan, C2 visible-light region (fulvic acid-like), and C3-like humic acid (humic acid-like) components. Among them, the DOM of the leaf leachate mainly contributed the C2 visible light region (fulvic acid-like) components to the water body, and the DOM of the leaching solution of the grass stems and rice straw mainly contributed the C1-like tryptophan and C3-like humic acid components to the water body. Through principal component analysis, the DOM components of the grass stem and rice straw extracts showed similar characteristics; C1 and FI showed a significant (p<0.05) positive correlation, while C2 and C3 showed a very significant (p<0.01) positive correlation with FI and HIX index, respectively. The three components were significantly positively correlated with NO3-N. C3 was significantly positively correlated with NH4+-N. The management measures of agricultural wastes should be strengthened to reduce the transport of DOM produced by agricultural wastes to the water environment way. [ABSTRACT FROM AUTHOR]

• Enhanced Sensitivity: achieved low LODs and interference-free electropherograms. • Clinical Applicability: successfully analyzed human serum samples. • Innovative Methodology: integrated UA-DLLME and LVSS for analysis of two pairs of barbiturate enantiomer drugs. • Sensitivity Boost: attained a 6200–6400-fold sensitivity enhancement. • Efficient Analysis: provided a simple, high-efficiency method for biosample analysis. A rapid, straightforward, and sensitive approach to quantifying enantiomeric barbiturates in serum was developed by integrating ultrasound-assisted dispersive liquid–liquid microextraction (UA-DLLME) with large-volume sample stacking (LVSS) in capillary electrophoresis (CE). UA-DLLME was employed for sample preparation, and on-column preconcentration by using LVSS with polarity switching was implemented to enhance sensitivity. We thoroughly investigated and optimized various parameters influencing extraction and stacking to achieve optimal detection performance with the highest enrichment efficiencies. Under optimal extraction conditions (injection of a mixed solution containing 40 μL of CHCl 3 and 200 μL of tetrahydrofuran into 1 mL of a sample solution at pH 10.0), LVSS was performed using 600 mM Tris-boric acid (pH 9.5) containing 35 mM hydroxypropyl-β-cyclodextrin and sodium taurodeoxycholate hydrate. A voltage of 20 kV was applied and a preinjection water plug was loaded at a height of 25 cm for 10 s. Subsequently, the sample solution was injected at a height of 25 cm for 480 s, after which a voltage of −20 kV was applied and the sample stacking was initiated. The stacking process was completed when 95 % of the separation current was attained. Under optimized conditions, the contraction folds of the four barbiturate analytes (R, S -Secobarbital, R, S -pentobarbital) were improved by approximately 6400-fold, achieving detection limits of 0.1 ng/mL. The limits of quantification for all analyte enantiomers were 0.5–50 ng/mL, demonstrating good linearity (r > 0.997). Migration times exhibited a relative standard deviation of less than 1.7 %, whereas peak areas for the four analytes exhibited a deviation of 8.7 %. Finally, the established method was effectively applied to the analysis of human serum samples. [ABSTRACT FROM AUTHOR]

In order to improve the effect of modern music teaching, this paper builds an intelligent music teaching system based on machine learning and SVM algorithm, innovates the music teaching process, and gradually expands from the simplest three-layer structure BPNN to a multi-layer structure. Moreover, this paper proposes a method of dividing the error by the proportion of each link's contribution to the error, and the idea that the error of the hidden layer node is the sum of the errors on each link during the forward propagation process. In addition, this paper combines the actual needs of music teaching to construct an intelligent music teaching system. Finally, this paper conducts training tests on music teaching data and sets up the experimental group and the control group to evaluate the system teaching effect based on actual needs. The research results show that the performance of the intelligent music teaching system constructed in this paper is good. [ABSTRACT FROM AUTHOR]

• A facile preparation of TA-AuNRs as catalysts was demonstrated. • TA-AuNRs showed excellent catalytic reduction of 4-NP with NaBH 4. • Good catalytic activity with k app of 0.0827 min−1 toward 4-NP. • High stability and reusability of TA-AuNRs catalyst. • TA-AuNRs were efficient for the reduction of 4-NP in water samples. The conversion of 4-nitrophenol (4-NP) into 4-aminophenol (4-AP) with sodium borohydride (NaBH 4) is the most used chemical reaction for investigating the catalytic activity of various nanomaterials by ultraviolet–visible (UV–Vis) absorption spectroscopy. Herein, a simple approach is reported for the preparation of tannic acid-functionalized gold nanorods (TA-AuNRs), which functioned as catalysts for the reduction of 4-NP with NaBH 4. Various processes including UV–Vis absorption spectroscopy, transmission electron microscopy, X-ray diffraction, Fourier transform infrared spectroscopy, zeta potential, and X-ray photoelectron spectroscopy were employed to characterize the TA-AuNRs. They exhibited good catalytic activity during the conversion of 4-NP. Under optimal conditions, the conversion efficiency was up to 79.04% in 20 min. The reduction reaction followed the pseudo-first-order kinetics, and the rate constant was estimated to be 0.0827 min−1. The active species responsible for the conversion efficiency were investigated through scavenger experiments using 1,4-benzoquinone, isopropyl alcohol (IPA), and ammonia oxalate as scavengers. The conversion efficiency decreased to 35.74% in the presence of IPA, indicating that hydroxyl radicals were the main species that degraded 4-NP. Finally, five recycling steps confirmed the reusability and practical application potential of the TA-AuNRs for the catalytic reduction of water samples spiked with 4-NP. [Display omitted] [ABSTRACT FROM AUTHOR]

Pesticides are a family of non-biodegradable chemical compounds which widely used in agriculture to control pests and increase yield production. However, overuse or abuse of pesticides and their metabolites may cause potential toxicity for the environment as well as human health and all other living organisms, even at deficient concentrations. Consequently, the development of sensors for monitoring these compounds is significant. Recently, nanoparticles-based sensors have been extensively employed as a potential alternative or complementary analytical tool to conventional detection methods for pesticides. Among them, gold nanoparticles (AuNPs) owing to their unique optical properties have been developed as smart sensors with high selectivity, sensitivity, simplicity, and portability. These comprehensive reviews have summarized various studies performed based on different detection strategies, i.e., colorimetric, fluorescence, surface-enhanced Raman scattering, and electrochemical, using AuNPs as sensing probes for pesticide analysis in various matrices. Additionally, the current challenges and future trends for developing novel AuNPs-based sensors for the detection of pesticides are also discussed. [ABSTRACT FROM AUTHOR]

A rapid, simple, and sensitive technique for the quantitative detection of fluoxetine and norfluoxetine enantiomers in biological fluids was developed based on the combination of field-amplified sample stacking (FASS)–related capillary electrophoresis (CE) with ultrasound-assisted dispersive liquid–liquid microextraction (UA-DLLME). The extraction efficiency of UA-DLLME was strongly related to extraction time, salt concentration, type of extraction and dispersion solvents, and volume of extraction and dispersion solvents. The extracted fluoxetine and norfluoxetine enantiomers in a mixture of 50% methanol and 50% deionized water were efficiently stacked using FASS and then separated using cyclodextrin-modified CE. Under optimal conditions of FASS (chiral selector, 3 mM trimethyl-β-cyclodextrin; and background electrolyte, 100 mM phosphate buffer) and UA-DLLME (extraction solvent, 200 μL of acetone; and dispersed solvent, 50 μL of C2H2Cl4 in 1 mL of the sample solution), the obtained enrichment factors of fluoxetine and norfluoxetine enantiomers reached approximately 2000. The linear ranges for the quantification of fluoxetine and norfluoxetine enantiomers were 0.3–150 and 0.6–150 nM, respectively. The relative standard deviations in peak areas and migration time for four analytes were less than 3.3% and 6.3%, respectively. The proposed system provided limits of detection (signal-to-noise ratio of 3) for four analytes corresponding to 0.1 nM. The precision and accuracy for urine and serum samples were less than 6.8 and 8.3%, respectively. These findings suggested that the proposed system exhibited a high potential for the reliable determination of fluoxetine and norfluoxetine enantiomers in clinical samples. [ABSTRACT FROM AUTHOR]

The validity of an eight-band k·p method with the axial approximation for modeling the band structures and optical properties of type-II interband cascade lasers is assessed by comparing its results with those from the standard eight-band k·p method. Explicit expressions for anisotropic k·p interaction terms, which are neglected by the axial approximation, are obtained. Then the band structures and optical properties of practical type-II interband cascade lasers are calculated using both eight-band k·p methods and the numerical results are discussed in detail. It is found that the axial approximation may be problematical for the simulation of type-II interband cascade lasers. [ABSTRACT FROM AUTHOR]

This study developed a sensitive method involving capillary electrophoresis (CE) coupled with ultraviolet absorption for the simultaneous separation of chiral phenothiazine drugs at nanomolar concentration levels. The method consists of hydroxypropyl-γ-cyclodextrin (Hp-γ-CD) as a chiral selector and poly (diallyldimethylammonium chloride) (PDDAC)-based CE. Five pairs of d,l-phenothiazines were baseline separated using a background electrolyte containing 0.9% PDDAC, 5 mM Hp-γ-CD, and 100 mM tris(hydroxymethyl)aminomethane (Tris)-formate (pH 3.0). The five pairs were successfully stacked on the basis of the difference in viscosity between the PDDAC-containing background electrolyte and the sample solution, with almost no loss of resolution. The combination of a solid-phase extraction and PDDAC-mediated CE can efficiently improve the sensitivity of the phenothiazine enantiomers. Under optimal conditions, calibration graphs displayed the linear range between 6 and 1500 nM, with relative standard deviation values lower than 3.5% (n = 5). Detection limit ranged from 2.1 to 6.3 nM for target analytes, and 607- to 1555-fold enhancement was achieved. The practicality of using the proposed method to determine five pairs of d,l-phenothiazines in urine is also validated, in which recoveries between recoveries of all phenothiazines from urine ranged from 89% to 101%. [ABSTRACT FROM AUTHOR]

Integrated modular avionics (IMA) architecture is widely adopted for the design of modern aircraft. It simplifies the system development process and improves the system security and reliability. In IMA systems, avionics applications are packed into various partitions and integrated into a standard computing platform. How to determine the schedulability of systems is one of the key problems. In this paper, using the characters of avionics systems, a partition model with a strict period is built and constraints in space, time, and communication are analyzed. Based on the mixed integer linear programming formulation, a solution to determine the schedulability of IMA systems is presented. Experience reveals that this solution not only determines the system schedulability, but also achieves the required minimum number of modules and guides the design of IMA systems. [ABSTRACT FROM AUTHOR]

Background: The performance of single arc VMAT (VMAT1) for nasopharyngeal carcinoma (NPC) on the Axesse linac has not been well described in previous studies. The purpose of this study is to assess the feasibility of VMAT1 for NPC by comparing the dosimetry, delivery efficiency, and accuracy with dual arc VMAT (VMAT2), dynamic MLC intensity-modulated radiotherapy (dIMRT), and step-and-shoot intensity-modulated radiotherapy (ssIMRT).Methods: Twenty consecutive patients with non-metastatic NPC were selected to be planned with VMAT1, VMAT2, dIMRT and ssIMRT using Monaco 3.2 TPS on the Axesse™ linear accelerator. Three planning target volumes (PTVs), contoured as high risk, moderate risk and low risk regions, were set to receive median absorbed-dose (D50%) of 72.6 Gy, 63.6 Gy and 54 Gy, respectively. The Homogeneity Index (HI), Conformity Index (CI), Dose Volume Histograms (DVHs), delivery efficiency and accuracy were all evaluated.Results: Mean HI of PTV72.6 is better with VMAT1(0.07) and VMAT2(0.07) than dIMRT(0.09) and ssIMRT(0.09). Mean HI of PTV63.6 is better with VMAT1(0.21) and VMAT2(0.21) than dIMRT and ssIMRT. Mean CI of PTV72.6 is also better with VMAT1(0.57) and VMAT2(0.57) than dIMRT(0.49) and ssIMRT(0.5). Mean CI of PTV63.6 is better with VMAT1(0.76) and VMAT2(0.76) than dIMRT(0.73) and ssIMRT(0.73). VMAT had significantly improved homogeneity and conformity compared with IMRT. There was no significant difference between VMAT1 and VMAT2 in PTV coverage. Dose to normal tissues was acceptable for all four plan groups. VMAT1 and VMAT2 showed no significant difference in normal tissue sparring, whereas the mean dose of the parotid gland of dIMRT was significantly reduced compared to VMAT1 and VMAT2. The mean delivery time for VMAT1, VMAT2, dIMRT and ssIMRT was 2.7 min, 3.9 min, 5.7 min and 14.1 min, respectively. VMAT1 reduced the average delivery time by 29.8%, 51.1% and 80.8% compared with VMAT2, dIMRT and ssIMRT, respectively. VMAT and IMRT could all be delivered accurately based on our quality assurance standards.Conclusions: In the treatment of NPC using the Axesse™ linear accelerator, single arc VMAT has shown superiority to double arc VMAT, dIMRT and ssIMRT in delivery efficiency, without compromise to the PTV coverage. However, there is still room for improvement in terms of OAR sparing. [ABSTRACT FROM AUTHOR]

Abstract: A novel method for the determination of sertraline using dispersive liquid–liquid microextraction (DLLME) coupled with capillary electrophoresis (CE) was developed. Acetone and dichloromethane were used as the disperser solvent and extraction solvent, respectively. A mixture of the extraction and disperser solvents was rapidly injected into a 1.0mL aqueous sample to form a cloudy solution. After the extraction, sertraline was analyzed using CE that was equipped with UV detection. A 74-fold improvement in the sensitivity was observed when DLLME was used to extract sertraline. Since the DLLME extract residue was redissolved with 5μL of water that contained 20% methanol, the detection sensitivity was further enhanced through the use of field-amplified sample stacking (FASS). A 11-fold improvement in the sensitivity was obtained when FASS was used to on-line concentrate sertraline. Under optimal extraction and stacking conditions, the calibration curve, which ranged from 0.01 to 1μM was observed to be linear. The limit of detection (LOD) at a signal-to-noise ratio of 3 was 2.5nM for sertraline. An approximately 814-fold improvement in the sensitivity was observed for sertraline compare with injection of standard solution without the DLLME and FASS procedures. This developed method was successfully applied to the determination of sertraline in human urine samples. [Copyright &y& Elsevier]

Abstract: This paper presents on-line simultaneous concentration and separation of cationic and anionic neurochemicals by capillary electrophoresis (CE) with UV absorbance spectroscopy. Neurochemical stacking exploits differences in local electric field and viscosity between the sample zone and the background electrolyte (BGE). To achieve these discontinuous conditions for CE, neurochemicals were prepared in a solution containing 1mM formic acid and 20% (v/v) acetonitrile (ACN). The capillary was filled with a solution of 500mM Tris–borate (TB) and 10% (v/v) glycerol. The buffer vial contained 500mM TB and 0.5% (v/v) polyethylene oxide (PEO). After injecting a large sample volume, PEO enters the capillary by electro-osmotic flow (EOF). Anionic neurochemicals stacked at the sample zone and PEO-containing BGE boundary. Simultaneously, cationic neurochemicals were concentrated at the boundary between the sample zone and the glycerol-containing BGE. The concentrated cationic neurochemicals were baseline separated in the presence of glycerol, mainly due to hydrogen bonding interactions between glycerol hydroxyl groups and the neurochemical''s hydroxyl and amino groups. Under optimal stacking conditions, we observed the following: (a) the maximum sample injection volume was 720nL; (b) the limit of detection for signal-to-noise ratio of 3 ranged from 14.7 to 313.4nM; and (c) sensitivity enhancements compared to normal injection (15nL) ranged from 116 to 281-fold. We evaluated the proposed method by the determination of neurochemicals in urine samples. [Copyright &y& Elsevier]

Abstract: We describe the stacking and separation of d- and l-aspartic acid (Asp) by capillary electrophoresis (CE) with light-emitting diode-induced fluorescence detection (LEDIF). In the presence of cyanide, d- and l-Asp were derivatized with naphthalene-2,3-dicarboxaldehyde (NDA) to form fluorescent derivatives prior to CE-LEDIF. The separation of NDA-derivatized d- and l-Asp was accomplished using a discontinuous system – buffer vials contained a solution of 0.6% poly(ethylene oxide) (PEO), 150mM sodium dodecyl sulfate (SDS), and 60mM hydroxypropyl-β-cyclodextrin (Hp-β-CD), while a capillary was filled with a solution of 150mM SDS and 60mM Hp-β-CD. The role of PEO, Hp-β-CD, and SDS is to act as a concentrating media, as a chiral selector, and as a pseudostationary phase, respectively. This discontinuous system could be employed for the stacking of 600nL of NDA-derivatized d- and l-Asp without the loss of chiral resolution. The stacking mechanism is mainly based on the difference in viscosity between sample zone and PEO as well as SDS sweeping. The limits of detection at signal-to-noise of 3 for d- and l-Asp were down to 2.4 and 2.5×10−10 M, respectively. Compared to normal sample injection volume (25nL), this stacking approach provided a 100- and 110-fold improvement in the sensitivity of d- and l-Asp, respectively. This method was further applied for determining d- and l-Asp in cerebrospinal fluid, soymilk, and beer. [ABSTRACT FROM AUTHOR]

Abstract: The combination of capillary electrophoresis (CE) and light-emitting diode-induced fluorescence (LED-IF) detection has been demonstrated in the analysis of major amino acids in tea leaves and beverages. The separation efficiency of amino acids, which were derivatized with naphthalene-2,3-dicarboxaldehyde (NDA), depended on the capillary length and PEO concentration. We suggested that the interactions between the NDA derivatives and poly(ethylene oxide) (PEO) molecules are based on hydrogen bonding, hydrophobic patches, and Van der Waals forces. The magnitude of EOF and the interactions between them can be further controlled by the capillary length. The separation of 17 NDA-amino acids derivatives was completed within 16min using 0.5% PEO and 60cm capillary length. The relative standard deviations (R.S.D.) of their migration times (n =5) were less than 2.7%. Additionally, the limits of detection at signal-to-noise ratio 3 for the tested amino acids ranged from 3.6 to 28.3nM. Quantitative determination of amino acids in tea leaves and beverages was accomplished by our proposed method. This study showed that amino acid present in highest concentration in tea leaves and beverages is γ-aminobutyric acid and theanine, respectively. The experimental results suggest that our proposed methods have great potential in the investigation of the biofunction of different tea samples. [Copyright &y& Elsevier]

Abstract: This paper describes a simple, sensitive, efficient, and rapid method for simultaneous analysis of biologically active amines and acids by capillary electrophoresis in conjunction with laser-induced native fluorescence detection (CE-LINF) using a diode pumped solid state nanolaser at 266nm. In order to optimize resolution of the amines that were prepared in 10.0mM formate-Tris (FT) solutions, 10.0mM FT solutions with and without containing halides were used to fill the capillary and reservoirs, respectively. The electrophoretic mobilities of tryptamine (TA) and serotonin (5-HT) at pH 4.0 decrease with the increase in halide concentration (0–10.0mM). Taken together with a great effect of iodide than other halides, we suggest that the formation of ion pairs is a main contributor for altering the migration of the amines. In order to simultaneously analyze the amines and their metabolites (acids) at low pH, a high bulk EOF is required. The analysis of 10 anlytes including amines and acids was completed within 12min by CE-LINF using a capillary treated with 0.5M NaOH and then filled with 10.0mM FT solutions (pH 4.0) containing 10.0mM KCl prior to analysis. The limits of detection for TA and 5-hydroxyindole-3-acetic acid (5-HIAA) are 0.12 and 6.0nM, respectively. The present method has been further validated by analyzing urine samples, with an RSD less than 3.1% (migration times) and 3.9% (concentration). [Copyright &y& Elsevier]

[Display omitted] • Good recoveries low LODs and interference-free electropherograms were obtained. • Elaborated technique was applied for human urine and serum samples analysis. • UA-DLLME and FASS in CE with C4D for the simultaneous analysis of three underivatized adamantane drugs. • Using this technique, 1300–1800-fold improvement in the sensitivity was obtained. • This technique provides simple, fast, cheap, biocompatible, underivatized sample and efficient method. Separation techniques are promising for the detection of adamantane analogs with various functional groups. The derivatization of adamantane analogs with chromophores or fluorophores should be conducted using a separation technique combined with a common ultraviolet–visible or fluorescence detector. However, limited research has been conducted on underivatized adamantane analogs. Therefore, we present a highly rapid and sensitive method for detecting underivatized adamantane analogs by integrating ultrasound-assisted dispersive liquid–liquid microextraction (UADLLME), field-amplified sample stacking (FASS)-related capillary electrophoresis (CE), and capacitively coupled contactless conductivity detection (C4D). In the proposed system, UADLLME is used for sample clean up and analyte enrichment, whereas FASS-related CE provides on-line concentration of underivatized adamantane analogs during CE separation. A mixture of memantine (MT), amantadine (AT), and rimantadine (RT) was separated at baseline within 8 min through the application of optimized UADLLME (mixing extraction solvent, 50 μL of 1,1,2,2-tetrachloroethane (C 2 H 2 Cl 4) and dispersive solvent, 200 μL of acetonitrile; mixing solution was injected into 1 mL of the sample solution at pH 12.5), FASS (buffer, 1.5 M acetic acid; additive, 0.05 mM β-cyclodextrin; pH 2.5), and C4D (amplitude, 2 V pp ; frequency, 500 kHz). The calibration curve exhibited acceptable linearity, with a coefficient of determination higher than 0.99. The limits of detection (signal-to-noise ratio of 3) were estimated to be 0.9, 1.0, and 1.2 nM for MT, AT, and RT, respectively. The relative standard deviations of peak areas varied from 8.9% to 9.3% (n = 5), whereas the sensitivity improvement of three underivatized adamantane analogs ranged from 1342 to 1766. The feasibility and accuracy of the present method for the determination of MT, AT, and RT in human serum and urine was satisfactorily confirmed by the excellent recovery and relative error. The proposed method exhibited high enrichment factors and offers excellent precision, high accuracy, and a short analysis time. [ABSTRACT FROM AUTHOR]

Encapsulating peptide-stabilized gold nanoclusters (AuNCs) with thiolated hyaluronic acid (HA-SH) and selectively adding cysteine to the peptide sequence increased their photoluminescence. We found that peptide compositions with cysteine in the middle emitted the most. RCR-stabilized AuNCs can be purified using size-exclusion chromatography to characterize their optical characteristics, chemical composition, and possible structure. Our findings show that RCR-stabilized AuNCs have a unique chemical structure, microsecond photoluminescence lifetime, good quantum yield, and near-infrared emission peak. Due to Au-S bonding and electrostatic interactions, RCR-stabilized AuNCs were encapsulated with HA-SH to create nanocomposites. HA-SH-AuNCs had a longer emission peak, greater particle size, and better photostability than RCR-stabilized AuNCs. HAase break down HA in HA-SH-AuNCs, changing their structure and size. Thus, centrifugation makes it easier to separate HA-SH-AuNCs from HAase-digested ones. Similar to earlier sensors, HA-SH-AuNCs have great sensitivity and selectivity for HAase, with a linear range of 0.5–6.0 U/mL and a detection limit of 0.39 U/mL. They were useful for urine HAase determination, with spike recovery of 103 % to 107 %. HA-SH-AuNCs further served as a platform for targeted imaging of CD44 receptor-expressing cancer cells, demonstrating bioimaging and clinical diagnostic potential. [Display omitted] [ABSTRACT FROM AUTHOR]

An 18-year-old male patient had presented with diffuse hyperpigmentation after birth and with adrenal insufficiency syndrome since childhood. After puberty, no secondary sexual signs developed. Laboratory examination showed an extremely high concentration of serum triglycerides (9.14 mmol/L) and plasma adrenocorticotropic hormone (>275 pmol/L), however, a low concentration of plasma free cortisone (<25.1-67.6 nmol/L). Abdomen computed tomography detected atrophy of both adrenals glands. [ABSTRACT FROM AUTHOR]

We have studied transport properties in a two-dimensional electron gas with equal Rashba and Dresselhaus spin-orbit interactions under a perpendicular magnetic field. By employing the exact solution for this system, we found resonant charge and spin Hall conductances at a certain magnetic field, where all the nearest neighboring Landau levels cross. Near this value of magnetic field, there exists a resonant spin polarization, which can also induce resonant charge and spin Hall effects. [ABSTRACT FROM AUTHOR]

Abstract A sensitive technique for the measurement of warfarin and its metabolic enantiomers in human fluids such as urine and serum technique was developed by applying ultrasound-assisted dispersive liquid-liquid microextraction linked with poly(ethylene oxide)-mediated stacking in capillary electrophoresis. The parameters that influence extraction and stacking performance-the type of the extraction and dispersive solvents and their volume, extraction time, salt additives, sample matrix, solution pH, and the composition of background electrolyte stacking-were carefully studied and optimized based on the considering of obtaining the best detection sensitivity. Under the optimal extraction (30 μL C 2 H 2 Cl 4 and 200 μL tetrahydrofuran in 1 mL of sample solution) and separation (0.5% PEO, 200 mM Tris-borate, pH 8.5, and 5 mM dimethyl-β-cyclodextrin) conditions, the enrichment factors of D-/L-warfarins and D-/L-7-OH warfarins covered from 1758 to 1859 and their limits of detection ranged from 0.34 to 0.38 nM. Calibration-related results exhibited acceptable linearity with the coefficient of determination higher than 0.99; the relative standard deviations of the peak area were determined to 4.1%–6.3% (n = 3). The recovery of four separated analytes spiked in samples of urine and serum was found to be 93%–110% and 95%–109%, respectively. We revealed that ultrasound-assisted dispersive liquid-liquid microextraction with poly(ethylene oxide)-mediated stacking in capillary electrophoresis could be a prompt and practical method for quantifying the levels of warfarin and its metabolic enantiomers in real-world samples, especially in biological fluids. Highlights • A enantiomer separation combined DLLME and CE for determination of warfarin and its metabolic enantiomers. • Detection of two pairs of warfarin and its metabolic enantiomers in nM concentration were achieved. • This method was applied for detecting warfarin and its metabolites enantiomers drugs in urine and plasma. [ABSTRACT FROM AUTHOR]

This study developed a facile, highly sensitive technique for extracting and quantifying barbiturates in serum samples. This method combined ultrasound and surfactant‐assisted dispersive liquid–liquid microextraction with poly(ethylene oxide)‐mediated stacking in capillary electrophoresis. Factors influencing the extraction and stacking performance, such as the type and volume of extraction solvents, the type and concentration of surfactant, extraction time, salt additives, sample matrix, solution pH, and composition of the background electrolyte, were carefully studied and optimized to achieve the optimal detection sensitivity. Under the optimized extraction (injecting 140 μL C2H4Cl2 into 1 mL of sample with pH 4 (5 mM sodium phosphate containing 0.05 mM Tween 20 and sonication for 1 min) and separation conditions (150 mM tris(hydroxymethyl)aminomethane‐borate with pH 8.5 containing 0.5% (m/v) poly(ethylene oxide)), the limits of detection (signal‐to‐noise ratio = 3) of five barbiturates ranged from 0.20 to 0.33 ng/mL, and the calculated sensitivity improvement ranged from 868‐ to 1700‐fold. The experimental results revealed excellent linearity (R2 > 0.99), with relative standard deviations of 2.1%–3.4% for the migration time and 4.3%–5.7% for the peak area. The recoveries of the spiked serum samples were 97.1% –110.3%. Our proposed approach offers a rapid and practical method for quantifying barbiturates in biological fluids. [ABSTRACT FROM AUTHOR]

• Within 2 min, UESA-DLLME can extract five pairs of phenothiazine drugs from complex samples. • The proposed technique successfully analyzed five pairs of phenothiazine drugs in real-world samples. • USEA-DLLME and FASI in CE with C4D for the simultaneous analysis of five pairs of phenothiazine enantiomer drugs. • Using this technique, 1200−2000 -fold improvement in the sensitivity was obtained. • This technique provides simple, clean-up, biocompatible, chromophored or unchromophored samples and highly efficient method. In this study, a simple, rapid, and ultrasensitive technique was developed to identify five pairs of phenothiazine drugs by using ultrasound-enhanced and surfactant-assisted dispersive liquid–liquid microextraction (UESA-DLLME), field-amplified sample injection with capillary electrophoresis (FASI-CE), and capacitively coupled capacitively coupled contactless conductivity detection (C4D). During the CE separation process, UESA-DLLME was used for sample clean-up and offline concentration, and FASI-CE was used for the online concentration of phenothiazine enantiomers. At baseline, the five pairs of phenothiazine enantiomer drugs required 18 min for separation. UESA-DLLME was then used to extract 0.01 mM Tween 80 at pH 10 from a sample solution (extraction solvent, 100 mL of dichloromethane). Subsequently, FASI was used to stack the sample solution (buffer, 30 mM 2-(N -morpholino)ethanesulfonic acid/aspartic acid, additive 4 mM hydroxypropyl-γ-cyclodextrin, pH 2.5), and C4D was used for signal detection (amplitude, 2 Vpp; frequency, 400 kHz). The results indicated that the linear range for quantifying all analyte enantiomers was 1.0–150 nM, with a coefficient of determination exceeding 0.99. In addition, the relative standard deviations in the migration time and peak areas for the 10 analytes were less than 3.2% and 7.2%, respectively. The proposed system has a limit of detection (LOD) for the 10 analytes at a signal-to-noise ratio of 3, ranging from 0.24 to 0.28 nM. The sensitivity enhancement, which compares the LOD 0 (limit of detection in the normal method) to LOD 1 (limit of detection achieved using the proposed UESA-DLLME-FASI-CE-C4D method), varies between approximately 1200 and 2000 for the 10 analytes. Analysis of the 10 separated analytes spiked in urine and serum samples revealed recovery rates of 88%–106% and 89%–105%, respectively. Therefore, this highly sensitive advanced technique was successfully used to analyze phenothiazine enantiomers in urine and serum samples. [ABSTRACT FROM AUTHOR]

In order to study the spectral characteristics of soil dissolved organic matter (DOM) under agricultural non-point source pollution in the Huaihe River Basin, this study collected the soil from the Pihe River, a first-order tributary of the Zhengyangguan River, and used the parallel factor analysis method (PARAFAC) to obtain two components of humus and protein. Soil dissolved organic carbon (DOC) content was significantly different under different land use types (P<0.01). The soil DOM in the Huaihe River Basin is affected by both terrestrial and microbial sources. The biological index (BIX) of forest soil is significantly larger than that of cultivated land at different depths, which is caused by the rich plant diversity of forest land. The humification degree of cultivated land soil is higher than that of forest land, and the humification effect of cultivated land soil fertility is stronger due to human factors. The humification index (HIX), BIX and fluorescence index (FI) have a good indication of the degree of soil humification. At the same time, the greater the BIX, FI and spectral slope ratio (SR), the greater the contribution of microorganisms to soil DOM. [ABSTRACT FROM AUTHOR]

Dispersive liquid-liquid microextraction was combined with acetonitrile stacking in capillary electrophoresis for the identification of three selective serotonin reuptake inhibitors (citalopram, fluoxetine, and fluvoxamine) in human fluids such as urine and plasma. Parameters that affect the extraction and stacking efficiency, such as the type and volume of the extraction and disperser solvent, extraction time, salt addition for dispersive liquid-liquid microextraction, and sample matrices, pH, and concentration of the separation buffer for stacking, were investigated and optimized. Under optimum conditions, the enrichment factors were in the range of 1195-1441. Limits of detection ranged from 1.4 to 1.7 nM for the target analytes. Calibration graphs displayed satisfied linearity with R2 greater than or equal to 0.9978, and relative standard deviations of the peak area analysis were in the range of 2.9-5.0% ( n = 3). The recoveries of all tricyclic antidepressant drugs from urine and plasma were in the range of 77-117 and 79-106%, respectively. The findings of this study show that dispersive liquid-liquid microextraction acetonitrile-stacking capillary electrophoresis is a rapid and convenient method for identifying tricyclic antidepressant drugs in urine and plasma. [ABSTRACT FROM AUTHOR]

• We obtained satisfactory recoveries, good sensitivity, and non-interfering eletrophoretic analysis. • Our developed system was used to quantify mirtazapine-related drugs in human fluids. • Ultrasensitive analysis of mirtazapine-related drugs was achieved by the proposed system. • The sensitivity was improved to 2700–3900 times by USA-DLLME and PDDAC-mediated CE stacking. • This system has the merits of simplicity, rapidity, separation efficiency, and sensitivity. A simple, rapid, and sensitive technique for measuring mirtazapine and its metabolites enantiomers in human fluids, such as urine and serum, was developed by applying ultrasound-enhanced and surfactant-assisted dispersive liquid–liquid microextraction (USA-DLLME) integrated with poly(diallyldimethylammonium chloride) (PDDAC)-mediated stacking in capillary electrophoresis (CE). The parameters that affect extraction and stacking performance, such as the extraction volume, surfactant types, surfactant concentrations, salt additives, extraction time, solution pH, and background electrolytes, were comprehensively studied and optimized to achieve optimal detection performance. Under optimal extraction conditions (injection of 120 µL of C 2 H 2 Cl 4 into 1 mL of a sample solution containing 0.05 mM Brij-35 at pH 10.0) and separation conditions (0.9% PDDAC, 10 mM phosphate, pH 3.0, and 20 mM dimethyl-β-cyclodextrin), on-line CE stacking of mirtazapine-related chiral drugs was achieved by the two strategies: (i) neutral DM-β-CD sweep low concentrations of DL-NaSSA and (ii) DL-NASSA is stacked by the difference in the viscosity between the PDDAC and sample zone. An approximately 2,800–4000-fold improvement in detection sensitivity was revealed for mirtazapine, N-demethylmirtazapine, and 8-hydroxymirtazapine enantiomers. The linear ranges for the quantification of all analyte enantiomers were 1.2–150 nM, with a coefficient of determination higher than 0.99; the relative standard deviations in the migration time and peak areas for six analytes were less than 1.8% and 5.8%, respectively. The proposed system provided the limits of detection (signal-to-noise ratio of 3) of the six analytes as 0.3–0.5 nM. The recovery of the six separated analytes spiked in urine and serum samples was revealed to be 82.7%–109.5% and 91%–112.8%, respectively. This advanced technique with high sensitivity enhancement factors was successfully employed to analyze mirtazapine and its metabolites enantiomers in urine and serum samples with reliability. [ABSTRACT FROM AUTHOR]

This work proposed a straightforward synthesis of copper nanoclusters (CuNCs) with an emission wavelength of 496 nm and a quantum yield of 2.2% by directly using pepsin as a template with low toxicity NaBH4 and ascorbic acid as reducing agents. The chemical composition and optical properties of the pepsin‐stabilized CuNCs (pepsin‐CuNCs) were well‐characterized by spectroscopy‐related techniques. The pepsin‐CuNCs retained the fluorescence intensity at neutral pH, at 37°C, and in high salinity, proving their suitability in biological systems. Although the pepsin‐CuNCs remained only half of the initial fluorescence intensity after 24 days due to air oxidation, their storage stability was comparable to that of CuNCs reported in the literature. Given that the absorption peaks of hemoglobin overlap the excitation and emission wavelengths of pepsin‐CuNCs, this feature allowed pepsin‐CuNCs to serve as a luminescence turn‐off sensor for sensing hemoglobin through the inner‐filter effect process. The pepsin‐CuNC probe provided a fast (within 1 min) platform for hemoglobin detection with a dynamic quantitative range of 0.1–10 μM and a detection limit of 70 nM. Importantly, the proposed probe was well‐suited to detect hemoglobin in nearly undiluted human urine, demonstrating its great potential for the clinical diagnosis of trace hemoglobin in urine. [ABSTRACT FROM AUTHOR]

High-speed capillary electrophoresis (CE) enables the simple, rapid, and inexpensive analysis of large sets of chiral samples in the pharmaceutical industry. Hence, we developed a novel method for separating enantiomers of d,l -phenothiazines simply and rapidly, based on using poly(diallyldimethylammonium chloride) (PDDAC) as an additive and hydroxypropyl-γ-cyclodextrin (Hp-γ-CD) as a chiral selector in capillary electrophoresis. Adding 0.9% PDDAC to the background electrolyte generated a stable, high, and reversed electroosmotic flow (EOF). Hp-γ-CD not only worked as a complexing agent to increase the chiral resolution between d,l -phenothiazines but also decreased the effective electrophoretic mobility of these drugs. Combining PDDAC and Hp-γ-CD as buffer additives enabled CE to achieve a high-speed enantioseparation of five pairs of d,l -phenothiazines. A decrease in capillary length and an increase in the intensity of the electric field further shortened the separation time. When the background electrolyte contained 0.9% PDDAC, 5 mM Hp-γ-CD, and 75 mM formic acid (pH 3.0), enantioseparation of the d,l -phenothiazines was attained within 230 s by applying a capillary length of 32.5 cm and an electric field of 292 V cm −1 . The limit of detection (LOD) of the d,l -phenothiazines at a signal-to-noise ratio of 3 ranged from 2 to 8 μM. We demonstrated the feasibility of this method by detecting the five pairs of d,l -phenothiazines in urine samples. [ABSTRACT FROM AUTHOR]

Abstract: This study combines Tween 20-capped gold nanoparticles (Tween 20-AuNPs) with capillary electrophoresis (CE) for ultrasensitive detection of thiol-containing peptides, including glutathione (GSH), γ-glutamylcysteine (γ-GCS), and phytochelatin analogs. By forming AuTween 20-AuNPs can selectively extract and enrich these thiols from a complicated matrix. A Tween 20 capping layer not only suppresses nonspecific adsorption, but also enables NPs to disperse in a highly salinity solution. Dithiothreitol removes thiol-containing peptides from the NP surface through ligand exchange. The released peptides are selectively derivatized with o-phthaldialdehyde (OPA) to form tricyclic isoindole derivatives. Extraction efficiency of five thiol-containing peptides with Tween 20-AuNPs was highly reliable in the Tween 20-AuNP concentration, time of extraction and desorption thiols, and sample volume. After injecting a large sample volume, the OPA-derivatized peptides migrate against the electroosmotic flow (EOF) and enter the polyethylene oxide (PEO) zone. The sensitivity of these peptides was improved by stacking them at the boundary between the sample and PEO zones. As a result, limits of detection (LODs) for five peptides were down to 0.1–6pM. Not only is the proposed method probably the first CE example for detecting dissolved thiols in seawater; it also has the lowest LODs for GSH, γ-GCS, and phytochelatins compared to other reported methods. [Copyright &y& Elsevier]

Abstract: In this article, we report a simple method for selective enrichment of aminothiols using Tween 20-capped gold nanoparticles (AuNPs) prior to capillary electrophoresis coupled with laser-induced fluorescence (CE-LIF). Compared to citrate-capped AuNPs, Tween 20-capped AuNPs exhibit the ability to disperse in a highly saline solution and selectively extract aminothiols through the formation of Au–S bonds. After extraction and centrifugation, 1mM thioglycollic acid (TGA) was utilized to remove aminothiols that attached to the NP surfaces. After a solution of 8.0mL aminothiols were extracted using 2× AuNPs (200μL), the extracted aminothiols derivatized with o-phthalaldehyde at pH 12.0 were detected by CE-LIF. As a result, the limits of detection at a signal-to-noise ratio of 3 for homocysteine (HCys), glutathione (GSH), and γ-glutamycysteine (Glu-cys) are 4013.2, 79.8, and 382.8pM, respectively. The use of this probe provided approximately 11-, 282-, and 21-fold sensitivity improvements for HCys, GSH, and Glu-cys, respectively. A practical analysis of HCys, GSH, and Glu-cys in human urine sample has been accomplished by this present method. [Copyright &y& Elsevier]

We developed a triple-readout probe for colorimetric, fluorescent, and fluorescence-lifetime sensing of alkaline phosphatase (ALP) through the hydrolyzed ascorbic acid phosphate (AAP)–mediated formation of silver nanoparticles (AgNPs) on Ag+-deposited MoS2 quantum dots (QDs). Ag+ ions were self-assembled on a monolayer MoS2 QD surface through the formation of Ag–S bonds. When ALP hydrolyzed AAP in an alkaline buffer, the resultant ascorbic acid (AA) triggered the reduction of the bound Ag+ ions into AgNPs on the MoS2 QD surface. The resultant AgNPs induced an efficient fluorescence quenching of the MoS2 QDs through simultaneous static and dynamic quenching processes, generated an intense surface plasmon resonance peak, and triggered a reduction in the fluorescence lifetime of the MoS2 QDs. Electron microscopy and spectroscopic techniques revealed the successful fabrication of Ag+-deposited MoS2 QDs and the ALP-mediated formation of AgNPs on the MoS2 QD surface. The linear quantification ranges for ALP were 0.05–2.5, 0.1–4, and 1–4 units L−1 in the fluorescent, colorimetric, and fluorescence-lifetime detection modes, respectively. In addition, the proposed probe integrated with an ALP-linked sandwich immunoassay exhibited high sensitivity and selectivity for the fluorescence sensing of rabbit immunoglobulin G with a detection limit of 8 pg mL−1 and linear range of 25–1000 pg mL−1. The sensitivity of the probe is comparable to those of previously reported immunoassays involving ultrasensitive electrochemical detection, hydrogen evolution reactions, or electron spin resonance. The probe integrated with the sandwich assay serves as a promising platform for the detection of target proteins in clinical samples. [ABSTRACT FROM AUTHOR]

PD-L1 is a promising therapeutic target in aggressive cancers. However, immune landscapes and cancer hallmarks of human PD-L1+ tumors, as well as their roles in determining therapeutic efficacies are unknown. Here we identified, in detailed studies of gene data regarding 9769 patients of 32 types of human cancers, that PD-L1 could not exclusively represent IFN-γ signature and potentially signified pro-inflammatory myeloid responses in a tumor. PD-L1 heterogeneity endowed by local immune landscapes controlled cancer hallmarks and clinical outcomes of patients. Mechanically, NF-κB signal elicited by macrophage inflammatory responses generated PD-L1+ cancer cells exhibiting capabilities to aggressively survive, support angiogenesis, and metastasize, whereas STAT1 signal triggered by activated T cells induced PD-L1+ cancer cells susceptive to apoptosis. Importantly, PD-L1+ cancer cells generated by macrophages established great resistance to conventional chemotherapy, cytotoxicity of tumor-specific effector T cells, and therapy of immune checkpoint blockade. Therapeutic strategy combining immune checkpoint blockade with macrophage depletion or NF-κB inhibition in vivo effectively and successfully elicited caner regression. Our results provide insight into the functional features of PD-L1+ tumors and suggest that strategies to influence functional activities of inflammatory cells may benefit immune checkpoint blockade therapy. [ABSTRACT FROM AUTHOR]

Abstract Citrate-capped gold nanoparticles (AuNPs) modified with thrombin-binding aptamer are often implemented for colorimetric, fluorescent, and electrochemical detection of thrombin in an aqueous solution. However, researchers have rarely explored the application of fibrinogen-modified AuNPs (F-AuNPs) for thrombin sensing. We present a simple, inexpensive, sensitive, and selective probe for colorimetric assay of thrombin through combining thrombin-induced inclusion of F-AuNPs into Fibrin and F-AuNPs-catalyzed reduction of 4-nitrophenol with an excess amount of NaBH 4. Considering that fibrinogen stabilized citrate-capped AuNPs against a high-ionic-strength buffer, F-AuNPs efficiently catalyzed the NaBH 4 -mediated decrease of yellow 4-nitrophenol to colorless 4-aminophenol. The presence of thrombin converted fibrinogen into fibrin on the nanoparticle surface, leading to the inclusion of nanoparticles into fibrin. The formation of fibrin inhibited that the AuNPs catalyzed the NaBH 4 -mediated reduction of 4-nitrophenol. Consequently, the color of the solution gradually varied from colorless to yellow with increasing thrombin concentration. The proposed system was shown to be accurate in the quantification of small differences in the concentration of human thrombin over the range of 4–60 pM. The lowest detectable concentration of human thrombin by the naked eye was as low as 16 pM. We demonstrated the practical application of the proposed system in quantifying 1–15 nM human thrombin in human plasma. Graphical Abstract Unlabelled Image Highlights • Fibrinogen-capped gold nanoparticles provide excellent catalytic activity. • Fibrin-encapsulated gold nanoparticles exhibit poor catalytic activity. • The proposed system can detect 4–60 pM thrombin with excellent selectivity. • The proposed system can sense 1–15 nM thrombin in human plasma. [ABSTRACT FROM AUTHOR]

Objective: To compare the dosimetric and efficiency differences for left-sided breast cancer radiotherapy after breast-conserving surgery among three different planning techniques: double-arc volumetric-modulate arc therapy (VMAT), step-shoot intensity-modulated radiotherapy (sIMRT) and three-dimensional conformal radiation therapy (3D-CRT).Materials and Methods: A total of 17 female patients with left-sided breast cancer who underwent breast-conserving surgery were selected; the prescription doses were 50 Gy in 25 fractions. For every patient VMAT, sIMRT and 3D-CRT plans were generated within the Monaco treatment planning system for an Axesse™ accelerator equipped with the Agility MLC. The Conformity Index (CI), the Homogeneity Index (HI), the dose volume histogram (DVH) parameters for the organs at risk and the delivery efficiency were evaluated.Results: The VMAT plans showed on average higher CI of PTV (0.77 ± 0.03) than both sIMRT (0.68 ± 0.02) and 3D-CRT (0.55 ± 0.04) plans (P< 0.05). The HI values in the VMAT, sIMRT and 3D-CRT plans were 0.10 ± 0.01 0.09 ± 0.01 and 0.13 ± 0.01 (P> 0.05), respectively, and the differences among the three techniques were not statistically significant. In the ipsilateral lung, the VMAT plans showed lower Dmean, V30, V20, and V10 than the sIMRT and 3D-CRT (P< 0.05); however, there was no significant difference in V5. In the heart, the VMAT plans had lower V30 and V20 than the sIMRT and 3D-CRT plans (P< 0.05), but there was no significant difference in the Dmean and V5. In the contralateral lung, the VMAT plans showed higher Dmean and V5 than sIMRT and 3D-CRT (P< 0.05). In the contralateral breast, the VMAT plans had a higher V5 than the sIMRT and 3D-CRT plans (P< 0.05). The VMAT plans had higher MU's than sIMRT and 3D-CRT, while the treatment times were lower than that of sIMRT.Conclusion: For left-sided breast cancer radiotherapy after breast-conserving surgery, the VMAT plans had a better CI than the sIMRT and 3D-CRT plans. The VMAT and the sIMRT plans had better HI than the 3D-CRT plans, but no significant difference was observed between VMAT and sIMRT. [ABSTRACT FROM AUTHOR]

In this study, we present a case of a 52-year-old male with a chondrosarcoma of the left lamina of the thyroid cartilage. Pre-operative evaluations detected typical calcifications and delineated the extent of the tumor. The patient underwent a total laryngectomy to ensure the complete resection of the tumor. The tumor was histopathologically found to consist of chondrocytes in a hyaline cartilage matrix. The patient's postoperative course has been successful apart from the permanent tracheostomy. Herien, we discuss the methods and rationales for the diagnosis and management of and recovery from this rare tumor, and also provide a review of the literature. [ABSTRACT FROM AUTHOR]

Angiotensin II type 1 receptor (AT1R) blockers (ARBs) have been shown to reduce the incidence of type 2 diabetes mellitus; however, the underlying molecular mechanism is unknown. Peroxisome proliferator-activated receptor γ (PPARγ) is the central regulator of insulin and glucose metabolism, which improves insulin sensitivity. Whether candesartan cilexetil, as a prodrug of the AT1R blocker candesartan, has PPARγ-activating properties remains to be elucidated. The aim of the present study was to investigate the effects of oral administration of candesartan cilexetil on glucose tolerance and the actions of PPARγ on liver and adipose tissue in the insulin-resistant obese rat induced by high-fat diet. Animals treated with candesartan cilexetil showed an improved glucose tolerance after oral glucose challenge. Whole-body insulin sensitivity was evaluated using the hyperinsulinemic-euglycemic clamp technique. During high-fat feeding in high-fat diet (HF) rats, the glucose infusion rate (GIR) was 52.3% lower than that in normal chow (NC) rats. However, the GIR was significantly enhanced following candesartan cilexetil treatment. Angiotensin II receptor antagonism also resulted in significant increases in PPARγ protein expression in adipose and liver tissue. These results indicate that PPARγ activation by candesartan cilexetil may provide novel therapeutic options in the treatment of patients with metabolic syndrome. [ABSTRACT FROM AUTHOR]

Background: Type B insulin resistance is a rare autoimmune disease characterized by the presence of autoantibodies against the insulin receptor. Helicobacter pylori (H pylori) infection may play a causative role in the autoimmune diseases. Case presentation: Here, we present a rare case of a 48-year old female patient, who had type B insulin resistance with systemic scleroderma and was successfully treated with multiple immune suppressants after eradication of Helicobacter pylori infection. Conclusion: The present case suggests H pylori infection-related pathological mechanism may contribute to type B insulin resistance syndrome and autoimmune disorders. Treatment toward H pylori may be helpful to relieve syndrome of type B insulin resistance for H pylori positive patients. [ABSTRACT FROM AUTHOR]

Abstract: This study proposes a sensitive method for the simultaneous separation and concentration of 9 pairs of amino acid enantiomers by combining poly(ethylene oxide) (PEO)-based stacking, β-cyclodextrin (β-CD)-mediated micellar electrokinetic chromatography (MEKC), and 9-fluoroenylmethyl chloroformate (FMOC) derivatization. The 9 pairs of FMOC-derivatized amino acid enantiomers were baseline separated using a discontinuous system, and the buffer vials contained a solution of 150mM Tris-borate (TB), 12.5% (v/v) isopropanol (IPA), 0.5% (w/v) PEO, 35mM sodium taurodeoxycholate (STDC), and 35mM β-CD, and the capillary was filled with a solution of 1.5M TB, 12.5% (v/v) IPA, 35mM STDC, and 35mM β-CD. Based on the difference in viscosity between the sample zone and PEO solution and because of the STDC sweeping, the discontinuous system effectively stacked 670nL of the 9 pairs of FMOC-derivatized amino acid enantiomers without losing chiral resolution. Consequently, the limits of detection for the 9 pairs of FMOC-derivatized amino acid enantiomers were reduced to 40−60nM. This method was successfully used to determine d-Tryptophan (Trp), l-Trp, d-Phenylalanine (Phe), l-Phe, d-Glutamic acid (Glu), and l-Glu in various types of beers. [Copyright &y& Elsevier]

Tumor-induced osteomalacia (TIO) is an extremely rare metabolic bone disease and the occult offending tumor arising in facies cranii is even more uncommon. In this report, we described 2 middle-aged females with TIO caused by the tumor in facies cranii, which had ever been misdiagnosed as rheumatoid arthritis. Case 1 was present with diffuse bone pain and muscle weakness for 4 years, as well as esotropia in the right eye for 1 month. Case 2 was present with progressive bone pain in low back and hip for 2 years. Biochemical studies both showed persistent hypophosphatemia and urinary over wasting phosphate. Radiological examinations revealed the infiltrative mass in right apex partis petrosae ossis temporalis in case 1, and the soft mass in left nasal cavity and ethmoid sinuses in case 2, respectively. The offending tumors were resected completely in case 2, however, incompletely in case 1. Pathology examination revealed mixed connective tissue variant phosphaturic mesenchymal tumors. In conclusion, TIO should be presumed in patients presenting with unexplained persistent hypophosphatemia osteomalacia, also a thorough detection for tumor in facies cranii should be performed. [ABSTRACT FROM AUTHOR]

Background: Dihydroartemisinin (DHA), a semi-synthetic derivative of artemisinin, has recently shown antitumor activity in various cancer cells. Apo2 ligand or tumor necrosis factor-related apoptosis-inducing ligand (Apo2L/TRAIL) is regarded as a promising anticancer agent, but chemoresistance affects its efficacy as a treatment strategy. Apoptosis induced by the combination of DHA and Apo2L/TRAIL has not been well documented, and the mechanisms involved remain unclear. Methodology/Principal Findings: Here, we report that DHA enhances the efficacy of Apo2L/TRAIL for the treatment of pancreatic cancer. We found that combined therapy using DHA and Apo2L/TRAIL significantly enhanced apoptosis in BxPC- 3 and PANC-1 cells compared with single-agent treatment in vitro. The effect of DHA was mediated through the generation of reactive oxygen species, the induction of death receptor 5 (DR5) and the modulation of apoptosis-related proteins. However, N-acetyl cysteine significantly reduced the enhanced apoptosis observed with the combination of DHA and Apo2L/TRAIL. In addition, knockdown of DR5 by small interfering RNA also significantly reduced the amount of apoptosis induced by DHA and Apo2L/TRAIL. Conclusions/Significance: These results suggest that DHA enhances Apo2L/TRAIL-mediated apoptosis in human pancreatic cancer cells through reactive oxygen species-mediated up-regulation of DR5. [ABSTRACT FROM AUTHOR]

Background: Laparoscopic approach has been increasingly used in the treatment of pancreatic benign diseases. This report evaluates our experience with laparoscopic surgery for pancreatic insulinomas.Methods: Between July 2000 and December 2007, laparoscopic pancreatectomy was attempted in 29 consecutive patients with insulinomas. The localization of tumors, operating characteristics, and clinical outcomes were analyzed.Results: Tumors were precisely localized in 28 of 29 (96.6%) patients by a combination of preoperative imaging techniques and intraoperative ultrasonography. Laparoscopic pancreatectomy was successfully performed in 26 patients, including enucleation (n = 14), hand-assisted enucleation (n = 2), and distal pancreatectomy with (n = 9) or without (n = 1) spleen preservation. Two conversions to open procedure were required because of unfavorable locations of the tumors. The pancreatic fistula occurred in four patients who underwent tumor enucleation. The median hospital stay was 5.5 days (range, 3-18 days) after laparoscopic procedure. Twenty-eight patients with pancreatic resection were free of symptoms and remained normoglycemic after a median follow-up period of 19 months (range, 10-36 months).Conclusion: Laparoscopic pancreatic resection is a feasible and safe procedure for patients with insulinomas. Further studies are required to evaluate the potential application of the hand-assisted approach for tumors located at anatomically unfavorable positions. [ABSTRACT FROM AUTHOR]

Abstract: Background: Disorder of the extracellular matrix has been suggested to play a role in the development of diabetic nephropathy. The aim of the present study was to examine the expression of matrix metalloproteinase-9 (MMP-9) in the kidney of Kkay mice, a type 2 diabetic model. Methods: Eight Kkay control mice (KA) and eight Kkay diabetic mice (KB) were fed with the same diets for 4 months and sacrificed after glucose levels and weight were measured. The renal pathological changes were examined by periodic acid–Schiff and periodic acid–silver methenamine staining, and the glomerulosclerosis indexes (GIs) were calculated. The levels of MMP-9 protein in the kidney tissue were assessed by immunohistochemistry. The gene expression of MMP-9 was measured by reverse transcription polymerase chain reaction. Results: The diabetic group had morphological findings of diabetic nephropathy, and their GI (240.0±17.3) was much higher than that of the control group (118.4±15.1) (P<.01). The mean positive area of MMP-9 protein in the glomeruli of Kkay mice in the KB group was higher than that in the KA group. The expression of MMP-9 messenger RNA level in the diabetic KB group was up-regulated when compared with the KA group. Conclusion: The expression of MMP-9 in the kidney of mice with diabetic nephropathy was enhanced, and MMP-9 might be involved in the development of diabetic nephropathy. [Copyright &y& Elsevier]

By using the traditional temperature-reduction method, KD2PO4(DKDP) crystals were grown from 85-deuterated aqueous solution synthesized by different kind of KH2PO4(KDP) raw materials. An experimental technique was employed to measure the variation of bulk damage threshold in plates of DKDP crystals. Bulk laser damage in unconditioned, thermal-conditioned and laser-conditioned type II tripler-cut DKDP crystals has been studied using 1064 nm (ω) and 355 nm (3ω) laser at pulse lengths of 5ns, 5ns respectively. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [ABSTRACT FROM AUTHOR]

Abstract: This paper tackles a simple and efficient method for the simultaneous separation and stacking of neurotransmitters in capillary electrophoresis with UV detection. By using poly(diallyldimethylammonium chloride) (PDDAC) as a buffer additive, the high and reversed EOF are observed. Moreover, the mobility of indolamines and catecholamines decreases as the PDDAC concentration increases. Based on the difference in mobility in the presence and absence of PDDAC, the analytes were simply stacked between the boundary of the sample zone and the background electrolyte containing PDDAC. The separation of 14 analytes including indolamines, catecholamines, and metanephrines was accomplished within 33min under optimal conditions (1.2% PDDAC and 5mM formic acid at pH 4.0), and the values of relative standard deviation of their migration time were less than 3.1%. By applying stacking methods for fourteen analytes, we observed: (a) the sample injection volume of sample is up to 216nL, (b) the limits of detection at signal-to-noise of 3 range from 15.4 to 122.1nM, and (c) the sensitivity enhancements, compared to normal injection (12nL), range from 110- to 220-fold. Under the optimal stacking conditions, the present method has been applied to analyze of vanillomandelic acid, 5-hydroxyindole-3-acetic acid, dopamine, tryptamine, and 3-indoxyl sulfate in urine samples. [Copyright &y& Elsevier]