A high sensitive voltammetric method for rapid determination of thrombin spiked in whole blood by taking advantage of both aptamer-based recognition and the use of a nanoporous membrane has been developed. The nanoporous membrane not only acts as platform for the thrombin recognition but also as filter of the micrometric components such as white and red blood cells, consequently minimizing matrix effects. The protocol involves a sandwich format in the inner walls (200 nm diameter) of an anodized alumina oxide filter membrane (AAO). The analytical signal, by DPV oxidation of [Fe(CN)(6)](4-), is based on the blockage in the pores which affects the diffusion of [Fe(CN)(6)](4-) to the screen-printed carbon electrotransducer (SPCEs) modified with the membrane. By labeling the anti-thrombin IgG with AuNPs followed by silver enhancement a greater passive signal enhancement in comparison to the membrane blockage has been observed. The contribution of both electrostatic/steric effects in this blockage due to the subsequent formation of the aptamer-thrombin complex and the final sandwich assay is investigated. The efficiency of the system is also monitored by microscopic techniques. The resulted biosensing system allows detecting thrombin spiked in whole blood at very low levels (LOD 1.8 ng mL(-1)) which are within the range of clinical interest for the diagnostic of coagulation abnormalities as well as pulmonary metastasis.

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We report a highly sensitive immunoassay protocol based on the use of redox-modified multi-walled carbon nanotubes (MWNTs) as electrochemical labels. The MWNTs were coated with methylene blue (MB) at an optically-determined loading of 3.41 × 10(-3) mol g(-1), and were then attached to secondary antibodies (Ab(2)) by adsorption. As a model analyte mouse IgG was collected by primary antibody (Ab(1))-coated magnetic beads. Following binding of the MB-MWNT-Ab(2) conjugates, IgG could be measured by MB reduction. Using differential pulse voltammetry for quantification, IgG was calibrated with a dynamic range of 0.1 pg mL(-1) to 100 pg mL(-1). Given the different possible Ab(1)-MB-MWNT-Ab(2) orientations on the magnetic beads, it was likely that not all the MB communicated with the electrode. A greater quantity of MB could be accessed by using the Fe(CN)(6)(3-/4-) redox couple as a solution phase mediator. This enabled us to lower the dynamic range down to 5 fg mL(-1) to 100 fg mL(-1).

PYR exhibited a more potent anti-inflammatory activity than CUR. This activity is partly mediated by PYR-depended inhibition of the JNK signaling pathway and underscores the utility of PYR as an anti-inflammatory agent in macrophages.

Stephania venosa (Blume) Spreng. is a medicinal herb wildly used as a folklore medicine in Thailand. Many studies have reported that S. venosa tuber revealed a variety of pharmacological activities including anti-malarial, anti-microbial, anti-cancer, anti-oxidant, and anti-inflammatory activities. In this study, we investigated the effects of (–)-stephanine and dehydrostephanine isolated from S. venosa tuber on anti-inflammation in lipopolysaccharide (LPS)-activated RAW264.7 macrophages. RAW264.7 cells were treated with (–)-stephanine and dehydrostephanine in the presence of LPS and cell viability was determined by MTT assay. The levels of inflammatory mediators, nitric oxide (NO) and pro-inflammatory cytokines were determined by Griess reagent and enzyme-linked immunosorbent assay, respectively. Pre-treatment of dehydrostephanine significantly suppressed NO secretion in LPS-activated RAW264.7 cells with the half-maximal NO inhibitory concentration (IC50) value of 26.81±0.25 μM. However, (–)-stephanine had IC50 value on the inhibition of NO secretion of >40 μM. In addition, dehydrostephanine at concentrations of 20 - 80 μM significantly reduced LPS-induced tumor necrosis factor-α, interleukin-1b, and interleukin-6 production in RAW264.7 cells. The present study showed that dehydrostephanine possesses the anti-inflammatory effect on LPS-activated RAW264.7 macrophages by suppression of inflammatory mediators. Dehydrostephanine may be a promising candidate compound for further investigation of a novel class of anti-inflammatory drug.