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In an HCl medium (pH 1.5), ligustrazine (2,3,5,6-tetramethylpyrazine, TMP) reacted with 12-tungstophosphoric acid (TP) to form a 3 : 1 ion-association complex. As a result, the intensities of resonance Rayleigh scattering (RRS), second-order scattering (SOS) and frequency doubling scattering (FDS) were greatly enhanced and new scattering spectra appeared. The maximum RRS, SOS and FDS wavelengths of the ion-association complexes were located at 379, 738 and 395 nm, respectively. The scattering intensity increments (Δ IRRS, Δ ISOS and Δ IFDS) were directly proportional to the concentration of ligustrazine within certain ranges. The detection limits (3σ) of RRS, SOS and FDS were 1.6, 3.2 and 2.8 ng/mL. Optimal conditions for the RRS method and factors influencing the method were discussed, and the structure of the ion-association complex and the reaction mechanism were investigated. Transmission electron microscopy (TEM) was used to characterize the structures of the ion-association complex. Based on the ion-association reaction and its spectral response, a rapid, simple and sensitive RRS method for the determination of TMP was developed. It was applied to the determination of TMP in tablet and urine samples with satisfactory results. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The work demonstrates a simple method for sensitive detection of Ca2+ ion by electrochemical response of alizarin red S (ARS) and Ca-ARS at a gold nanoparticle modified glassy carbon electrode (GCE). In the 0.1 M KOH, a sensitive reduction peak was observed at −0.795 V at the gold nanoparticles modified electrode. The peak currents were proportional to the concentrations of Ca2+ ion in the range of 2.0 × 10−7 M–1.2 × 10−4 M. For the different pulse voltammetry (DPV) methods, the detection limit was 2.57 × 10−8 M. The reaction mechanism was primarily determined by cyclic voltammetry, and the experimental results showed that the electrode processes were quasireversible responses of ARS and irreversible responses of ARS-Ca. In addition, the method was simple, fast, precise, and was used in the determination of calcium in blood serum with satisfactory results. [ABSTRACT FROM AUTHOR]

Abstract: Objective: This study is to explore the role of 78kD glucose-regulated protein (GRP78) in the development of hepatopulmonary syndrome (HPS) in rats. Methods: The rat model of liver cirrhosis and HPS were induced with multiple pathogenic factors. Hematoxylin and eosin (H & E) staining was performed to detect the pathological changes of the lung and liver tissues. The levels of alanine transferase (ALT), endotoxin, and tumor necrosis factor-α (TNF-α) in plasma and TNF-α and malondialdehyde (MDA) in lung tissues were detected. RT-PCR and Western blotting were conducted to detect the mRNA and protein expression levels of GRP78 in lungs. Results: The plasma endotoxin level was gradually increased as HPS developed, and the mRNA and protein expression levels of GRP78 in lungs were also increased as the disease progressed. The levels of ALT and TNF-α in plasma and the contents of TNF-α and MDA in lung tissues were gradually increased along with the disease progression, with a strong positive correlation. Compared with controls, the plasma TNF-α level and the mRNA and protein expression levels of GRP78 in lung tissues were significantly higher in rats with HPS. The levels of endotoxin and ALT in plasma and the level of MDA in lungs were significantly higher in rats with HPS than controls. Conclusions: The increased GRP78 expression is indicative of endoplasmic reticulum stress response during HPS, which may play an important role in the disease pathogenesis. [Copyright &y& Elsevier]

In an HCl medium (pH 1.5), ligustrazine (2,3,5,6-tetramethylpyrazine, TMP) reacted with 12-tungstophosphoric acid (TP) to form a 3 : 1 ion-association complex. As a result, the intensities of resonance Rayleigh scattering (RRS), second-order scattering (SOS) and frequency doubling scattering (FDS) were greatly enhanced and new scattering spectra appeared. The maximum RRS, SOS and FDS wavelengths of the ion-association complexes were located at 379, 738 and 395 nm, respectively. The scattering intensity increments (ΔIRRS , ΔISOS and ΔIFDS ) were directly proportional to the concentration of ligustrazine within certain ranges. The detection limits (3σ) of RRS, SOS and FDS were 1.6, 3.2 and 2.8 ng/mL. Optimal conditions for the RRS method and factors influencing the method were discussed, and the structure of the ion-association complex and the reaction mechanism were investigated. Transmission electron microscopy (TEM) was used to characterize the structures of the ion-association complex. Based on the ion-association reaction and its spectral response, a rapid, simple and sensitive RRS method for the determination of TMP was developed. It was applied to the determination of TMP in tablet and urine samples with satisfactory results., (Copyright © 2014 John Wiley & Sons, Ltd.)

Objective: To explore a simple and practical method of primarily culturing rat pulmonary microvascular endothelial cells (PMECs) in vitro, and observe the cell growth status and identify the PMECs., Methods: Wistar rats (n=40, aged 4-5 weeks) were sacrificed to take the lung tissue. After removal of pleura, the peripheral lung tissues were cut into pieces (1 mm(3)) in aseptic condition. The endothelial cells were cultured in the DMEM medium containing heparin sodium and in the RPMI1640 medium supplemented with special additives or not, respectively. Cell growth and morphology was observed under an inverted microscope. The expression of CD31 in cells was detected by immunofluorescence staining., Results: After incubation for 24 hours, PMECs in the medium containing special additives were the most in number and purity compared with the other two culture systems. At 24 hours, endothelial cells migrated from the lung tissue, and at 14 days, the cells aggregated and grew obviously, exhibiting a polygon shape, being tightly arranged and paving the base of Petri dish. After sub-culturing, the cells spread much more and most cells became spindle shaped, which showed a tendency of endothelial cell angiogenesis in vitro. CD31 was positive in immunofluorescence staining., Conclusion: The adherent culture method of tissue explants in the medium added by the special additives was proved to a good method to obtain a high-purity rat PMECs in vitro.