Publications by authors named "Wu Yijun"

In mice, lysophosphatidylcholine (LPC) was found to be a physiological substrate of neuropathy target esterase, which is also bound by organophosphates that cause a delayed neuropathy in human and some animals. However, the mechanism responsible for causing the different symptoms in mice and humans that are exposed to neuropathic organophosphates still remains unknown. In the present study, we examined and compared the effect of exogenous LPC on intracellular Ca(2+) overload in mouse N2a and human SH-SY5Y neuroblastoma cells.

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NTE-related esterase (NRE), conserved in mouse, rat and human, was a member of patatin-like phospholipases (PLPLA) with high homology to neuropathy target esterase (NTE). Little has been known about the characteristics of NRE and NRE functional esterase activity has yet not been defined. The C-terminal gene sequence of mouse NRE (mNREC) encoding 923-1,326 amino acid containing the patatin domain was first cloned and then expressed tagged with enhanced green fluorescence protein (EGFP) in mammalian cells.

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To explore the changes of the endogenous phosphorylation of brainstem mitochondrial and synaptosomal proteins in adult hens dosed with tri-o-cresyl phosphate (TOCP) following the development of organophosphate-induced delayed neurotoxicity (OPIDN). Verapamil (7mg/(kgday), i.m.

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Genetically engineered Escherichia coli, expressing the fusion protein of enhanced green fluorescent protein (EGFP) and carboxylesterase B1 (CarE B1), was successfully constructed by cloning the genes into the pET-28b vector and then transforming E. coli BL21 (DE3). Expression of the fusion protein was induced in E.

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Neuropathy target esterase (NTE) was originally identified as the primary target site of those organophosphorus compounds that induce delayed neuropathy in human and some animals. Here we examined the role of protein kinase C (PKC) in the regulation of the NTE activity in mammalian cells. Six-hour exposure of human neuroblastoma SK-N-SH cell to a PKC activator phorbol 12-myristate 13-acetate (PMA) decreased the activity of NTE, and this effect was blocked by the PKC inhibitor staurosporine.

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The residual level and dissipation rate of triazophos in wheat crops and the soil in which they were grown were determined by gas chromatography (GC). Maximum final residues of triazophos in wheat grain, stems and leaves, and soil were 1.865, 44.

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Lysophosphatidylcholine (LPC) is an important bioactive lipid. In the nervous system, elevated levels of LPC have been shown to produce demyelination. In the present study, we examined the effect of exogenous LPC on intracellular Ca2+ mobilization in human neuroblastoma SH-SY5Y cells.

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Neuropathy target esterase (NTE) was identified as the primary target of organophosphate compounds that cause a delayed neuropathy with degeneration of nerve axons. NTE is a novel phospholipase B anchored to the cytoplasmic face of endoplasmic reticulum and essential for embryonic and nervous development. However, little is known about the regulation of NTE.

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Cytoskeletal components play an important role in maintaining cellular architecture and internal organization, with clear involvement of defining cell shape, in cell division and other cellular processes, such as neurite extension and maintenance. Alterations of cytoskeleton in human neuroblastoma SK-N-SH cells after exposure to different concentrations of tri-ocresyl phosphate (TOCP) for 12 hr were investigated. TOCP decreased the cell viability in a dose-dependent manner; the viability of SK-N-SH was reduced to approximately 50% of baseline after a 12-hour exposure to TOCP at high concentration (5 mM).

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Objective: To construct the RNA interference expression vector for expression of human neuropathy target esterase (NTE) gene in mammalian cells.

Methods: Spe I and Xho I-digested insert from pSUPER, which comprised H1 RNA polymerase III promoter and the multiple cloning sites, were cloned into the compatible in the pcDNA3.1 (+) to generate pSUPER/neo that could express small interfering RNA in mammalian cells.

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Objective: To investigate the correlative factors of weight gain in very low birth weight infants (VLBW).

Methods: Fifty-one cases of VLBW from July 1998 to March 2004 were analyzed retrospectively.

Results: Twenty two cases were small for gestational age (SGA) and 29 cases were appropriate for gestational age (AGA).

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Carbamate esters are widely used as pesticides and can cause neurotoxicity in humans and animals; the exact mechanism is still unclear. In the present investigation, the effects of carbamates at sublethal concentration on neurite outgrowth and cytoskeleton as well as activities of acetylcholinesterase (AChE) and neuropathy target esterase (NTE) in differentiating human SK-N-SH neuroblastoma cells were studied. The results showed that 50 microM of either aldicarb or carbaryl significantly decreased neurite length in the retinoic acid-induced differentiation of the neuroblastoma cells, compared to cells treated with vehicle.

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Neuropathy target esterase (NTE) is inhibited and aged by organophosphorus compounds that induce delayed neuropathy in human and some sensitive animals. NTE has been proposed to play a role in neurite outgrowth and process elongation during neurodifferentiation. However, to date, there is no direct evidence of the relevance of NTE in neurodifferentiation under physiological conditions.

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Aim: To investigate the expression of cyclooxygenase-2 (COX-2) in gastric cancer and its relation with the liver metastasis and prognosis.

Methods: Expression of COX-2 mRNA and protein was examined in gastric cancer and its paired substantial normal tissue by semi-quantitative reverse transcription-polymerase chain reaction and immunohistochemistry. The relation between COX-2 expression and prognosis was investigated in 195 cases.

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Neuropathy target esterase (NTE) is phosphorylated and aged by oraganophosphorus compounds (OP) that induce delayed neuropathy in human and some animals. NTE has been proposed to play a role in neurite outgrowth and process elongation during neural differentiation. However, to date, there is no direct evidence of the relevance of NTE in neural differentiation under physiological conditions.

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Aim: Ischemia/reperfusion (I/R) injury is one of the major obstacles for intestinal transplantation (ITx). Urinary trypsin inhibitor (Ulinastatin, UTI) suppresses proteases and stabilizes lysosomal membranes. We supposed that Ulinastatin would diminish I/R injury of intestinal graft.

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To construct a hepatic stellate cells (HSCs) subtracted cDNA library to find differentially expressed genes in normal mice and mice infected with Schistosoma japonicum (S. japonicum). Suppression subtractive hybridization (SSH) was used.

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Objective: To explore the mechanism of cytotoxic effects of the organophosphates (OPs) with delayed neurotoxicity on human neuroblastoma cells.

Methods: The proliferation of neuroblastoma SH-SY5Y cells was determined by MTT spectrometry. (45)Ca uptake was determined by adding (45)CaCl(2) and tri-o-cresyl phosphate (TOCP) or methamidophos into the cultured medium for the SH-SY5Y cells.

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Objective: To explore the effect of organophosphorus insecticides (OPs) on the nicotinic autoreceptor function (NAF) in rat cortical synaptosomes and to understand alternative target of the OPs for human and other animals.

Methods: In vitro experiment, synaptosomes from the rats were incubated with [(3)H] choline and then superfused with physiological buffer. The [(3)H] acetylcholine release from the synaptosomes after the addition of paraoxon or chlorpyrifos to the superfusion system was recorded and the changes of NAF were calculated.

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Aim: To modify the hamster-to-rat liver xenotransplant technique to prevent postoperative complications, and to study the inhibiting effect of multiglycosides tripterygium wilfordii (T(II)) on immune rejection.

Methods: Female golden hamsters and inbred male Wistar rats were used as donors and recipients, respectively. One hundred and twelve orthotopic liver xenotransplants were performed by Kamada's cuff technique with modifications.

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p73, a p53 family member, is highly similar to p53 in both structure and function. Like p53, the p73 protein contains an N-terminal activation domain, a DNA-binding domain, a tetramerization domain, and several PXXP motifs. Previously, we and others have shown that some functional domains in p53, such as the DNA-binding and tetramerization domains, are required for inducing both cell cycle arrest and apoptosis whereas others, such as the second activation domain, the proline-rich domain, and the C-terminal basic domain, are only required for inducing apoptosis.

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Acetylcholine (ACh) release is modulated pre-synaptically by both muscarinic and nicotinic receptor-mediated processes. While muscarinic autoreceptors inhibit ACh release, nicotinic autoreceptors enhance ACh release and thus disruption of these processes could potentially affect cholinergic toxicity following exposure to anticholinesterases. Marked age-related differences in sensitivity to some organophosphorus (OP) anticholinesterases have been reported.

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The Burkholderia cepacia complex consists of at least five well-documented bacterial genomovars, each of which has been isolated from the sputum of different patients with cystic fibrosis (CF). Although the world-wide prevalence of this opportunist pathogen in CF patients is low (1-3%), 'epidemic' clusters occur in geographically isolated regions. Prevalence in some of these clusters is as high as 30-40%.

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