Publications by authors named "YanSong Li"

Stories of recent cases about melamine misuse to raise the false impression of a high protein content of milk in China emerged in September of 2008, have become an international health event. To meet the need for rapid and reliable monitoring of melamine in milk samples, a monoclonal antibody (mAb) was produced and an inhibition enzyme-linked immunosorbent assay (ELISA) was developed based on the mAb. The standard curve was linear in the range from 0.

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Abrin is a plant toxin, which can be easily isolated from the seeds of Abrus precatorius. It may be used as a biological warfare agent. In order to detect abrin in food samples, a two-layer sandwich format enzyme-linked immunosorbent assay based on the monoclonal antibody (mAb) (as capture antibody) and rabbit polyclonal serum (as detecting antibody) was developed and applied for the determination of abrin in some food matrices.

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IL6(T23)-PE38KDEL is a chimeric molecule composed of interleukin 6 (IL6), missing the N-terminal 23 amino acids, and fused to a truncated mutant form of Pseudomonas exotoxin (PE38KDEL). The aim of this study was to evaluate this recombinant immunotoxin in terms of its specific cytotoxicity to IL6R-overexpressing multiple myeloma (MM) cells in vitro, as well as its antitumor effects and side effects in vivo. IL6(T23)-PE38KDEL was expressed in Escherichia coli, refolded and purified from inclusion bodies.

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Background, Aim, And Scope: Okadaic acid (OA) and analogues of dinophysistoxin (DTX) are key diarrheic shellfish poisoning (DSP) toxins, which possibly arouse DSP symptoms by consuming the contaminated shellfish. Because of the stable toxicity in high temperature and the long-term carcinogenicity, the outbreaks of DSP related to consumption of bivalve mollusks contaminated by DSP toxins pose a hazard to public health. Therefore, it is worth developing a fast and reliable analytical method for the detection of OA and analogues in shellfish.

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Activation of the complement system has been associated with tissue injury after hemorrhage and resuscitation in animals. We investigated whether administration of recombinant human C1-esterase inhibitor (rhC1-INH), a regulator of complement and contact activation systems, reduces tissue damage and cytokine release and improves metabolic acidosis in a porcine model of hemorrhagic shock. Male Yorkshire swine were assigned to experimental groups and subjected to controlled, isobaric hemorrhage to a target mean arterial pressure of 35 mmHg.

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Blast-induced neurotrauma (BINT) is a major medical concern yet its etiology is largely undefined. Complement activation may play a role in the development of secondary injury following traumatic brain injury; however, its role in BINT is still undefined. The present study was designed to characterize the complement system and adaptive immune-inflammatory responses in a rat model of moderate BINT.

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Mercury ions (Hg(II)) are considered highly toxic and hazardous element even at low levels. The contamination of Hg(II) is a global problem. To develop selective and sensitive technique for the detection of Hg(II) has attracted considerable attention.

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A lateral flow immunochromatographic (LFIC) test strip based on a colloidal gold-monoclonal antibody (McAb) conjugate was developed for on-site rapid detection of okadaic acid (OA) in shellfish. It applies a competitive format using an immobilized toxin conjugate and free toxin present in samples. The McAb against OA was conjugated with 20-nm colloidal gold as detector reagent.

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The detection of heavy metal ions using enzyme-linked immunosorbent assays (ELISA) has been reported by several research groups. However, highly sensitive and selective detection of total heavy metal ions using ELISA is a major technical limitation. Here we describe the development of a versatile and highly sensitive probe combining goat anti-mice IgG, colloidal gold nanoparticles (AuNPs) and horseradish peroxidase (HRP).

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Background: Activation of complement system has been associated with tissue injury after hemorrhage and resuscitation in rats and swine. This study investigated whether administration of human recombinant decay-accelerating factor (DAF; a complement regulatory protein that inhibits classical and alternative pathways) reduces tissue damage in a porcine model of hemorrhagic shock.

Methods: Male Yorkshire swine assigned to four groups were subjected to controlled, isobaric hemorrhage over 15 minutes to a target mean arterial pressure of 35 mm Hg.

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A novel probe based on colloidal gold nanoparticles (AuNPs) modified with goat anti-mouse IgG and horseradish peroxidase (HRP) was synthesized and an enhanced enzyme-linked immunosorbent assay (ELISA) based on the probe was developed. In the assay, the synthesized probe is bound with a monoclonal antibody (McAb) which is competitively bound by coated BSA-ITCBE-Pb(II) on plate and Pb(II) in samples. The HRP, used here for signal amplification catalytically oxidize the substrate and generate optical signals that is related to the concentration of Pb(II) and can be measured spectrophotometrically.

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Mercury ions (Hg(2+)) are one of the most dangerous pollutants. Even at low concentration, it causes serious environmental and health problems. Current methods for the detection of Hg(2+) in environmental samples are tedious and time consuming because they require sophisticated instrumentation and complicated sample pre-treatment processes.

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Background: Activated complement system is known to mediate neuroinflammation and neurodegeneration following exposure to hypoxic-ischemic insults. Therefore, inhibition of the complement activation cascade may represent a potential therapeutic strategy for the management of ischemic brain injury. Decay-accelerating factor (DAF, also known as CD55) inhibits complement activation by suppressing the function of C3/C5 convertases, thereby limiting local generation or deposition of C3a/C5a and membrane attack complex (MAC or C5b-9) production.

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Background: C-reactive protein (CRP) is an acute pro-inflammatory mediator that has been demonstrated to enhance ischemia/reperfusion (IR) injury by virtue of activating the complement system. CRP is able to interact with complement proteins such as C1q, complement factor H, and C4b-binding protein. Since complement activation is central in the expression of tissue injury following IR, we have investigated the effects of human decay-accelerating factor (DAF), a complement inhibitor, on CRP-potentiated complement activation and tissue injury in mice subjected to mesenteric IR.

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The generation of monoclonal antibody (mAb) against marine toxins can serve as a valuable probe to detect this kind of compounds by immunological methods. However, traditional approaches to mAb generation usually need a comparative large quantity of standard substance (more than 400 microg mouse(-1)), and a comparative long immunization period (more than 6 weeks). Here we report a simple, inexpensive and fast protocol for the generation of monoclonal antibody probe specific for domoic acid (DA).

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One-step immunochromatographic assay using colloidal gold-labeled monoclonal antibody (Mab) probe for the rapid detection of brevetoxins (PbTxs) in fishery product samples was developed. The described assay was based on a competitive format using two antibodies. The primary antibody was conjugated with colloidal gold (detector reagent), the secondary antibody (capture reagent) was immobilized within a defined detection zone (control line) on a diagnostic cellulose nitrate membrane.

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Sodium cyanide-induced chemical hypoxia triggers a series of biochemical alterations leading to apoptosis in many cell types, including T cells. It is known that chemical hypoxia promotes inducible nitric-oxide synthase (iNOS) gene transcription by activating its transcription factors. To determine whether iNOS and NO production are responsible for chemical hypoxia-induced apoptosis, we exposed human Jurkat T cells to sodium cyanide in the presence or absence of iNOS inhibitors.

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Hemorrhage has been shown to increase inducible nitric oxide synthase (iNOS) and deplete ATP levels in tissues and geldanamycin limits both processes. Moreover, it is evident that inhibition of iNOS reduces caspase-3 and increases survival. Thus we sought to identify the molecular events responsible for the beneficial effect of geldanamycin.

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Exposure of T cells to inflammatory cytokines leads to phosphorylation-dependent activation of signal transducer and activator of transcription (STAT) 3. T cells from patients with systemic lupus erythematosus (SLE) display increased levels of total and phosphorylated STAT3 which resides primarily in the nucleus. Increased STAT3 is associated with increased expression of target genes.

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Systemic lupus erythematosus (SLE) is an autoimmune/inflammatory disease characterized by autoantibody production and abnormal T cells that infiltrate tissues through not well-known mechanisms. We report that SLE T lymphocytes display increased levels of CD44, ezrin, radixin, and moesin (ERM) phosphorylation, stronger actin polymerization, higher polar cap formation, and enhanced adhesion and chemotactic migration compared with T cells from patients with rheumatoid arthritis and normal individuals. Silencing of CD44 by CD44 small interfering RNA in SLE T cells inhibited significantly their ability to adhere and migrate as did treatment with Rho kinase and actin polymerization inhibitors.

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The influence of activated sludge properties on membrane fouling was investigated using statistical method. The results show that extracelluler polymeric substances (EPS), soluble microbial products (SMP), suspended solids in the supernatant (SSs), dynamic viscosity (micro), relative hydrophobicity (RH) and Zeta potential all have a significant influence on membrane permeability during microfiltration of activated sludge wastewater. The pearson's correlation coefficient (r(p)) for linear correlations between membrane fouling resistance and these sludge properties are 0.

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Hemorrhage in mice results in decreased ATP levels in the jejunum, lung, kidney, heart, and brain but not in liver tissue lysates, albeit at variable levels and time kinetics. The decreased protein expression and activity of pyruvate dehydrogenase (PDH) accounted for the hemorrhage-induced ATP loss. Treatment with geldanamycin (GA; 1 microg/g body wt), a known inducer of heat shock protein (HSP)70, inhibited the hemorrhage-induced ATP loss in the jejunum, lung, heart, kidney, and brain.

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Systemic lupus erythematosus (SLE) T cells express high levels of cAMP response element modulator (CREM) that binds to the IL-2 promoter and represses the transcription of the IL-2 gene. This study was designed to identify pathways that lead to increased binding of CREM to the IL-2 promoter in SLE T cells. Ca(2+)/calmodulin-dependent kinase IV (CaMKIV) was found to be increased in the nucleus of SLE T cells and to be involved in the overexpression of CREM and its binding to the IL-2 promoter.

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Sphingosine-1-phosphate (S1P) induces capillary formation of endothelial cells on Matrigel in accompany with actin assembly and accumulation of cortactin and Arp2/3 complex at the cell-leading edge. Suppression of cortactin expression with a cortactin antisense oligo significantly impaired S1P-induced capillary formation, migration of endothelial cells, and actin assembly at the cell periphery. Overexpression of wild-type cortactin tagged by green fluorescent protein (GFP) increased the S1P-induced tube formation and cell motility, whereas the cells overexpressing the mutant formed poorly capillary network and became less motile in response to S1P.

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The WASP and cortactin families constitute two distinct classes of Arp2/3 modulators in mammalian cells. Physical and functional interactions among the Arp2/3 complex, VCA (a functional domain of N-WASP), and cortactin were examined under conditions that were with or without actin polymerization. In the absence of actin, cortactin binds significantly weaker to the Arp2/3 complex than VCA.

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