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Organophosphorus Pesticides (OPPs) are a group of artificially synthesized substances used in farms to control pests and to enhance agricultural production. Although these compounds show preferential toxicity to insects, they are also toxic to humans and mammals by the same mode of action. ELISA now is an alternative method to detect OPPs. But, it must bear heterogenous properties, since several separation steps are needed during the ELISA method protocols. The FPIAs, which belong to homogenous assay, for determination of OPPs parathion and zainphos-methyl have been developed. The characteristics of Dep-EDF and PM-B-EDF tracers binding with antibodies A and D were investigated in the antibodies dilution experiments. The PM-B-EDF tracer combination with antibody D was selected to construct the standard curve for parathion detection. The IC50 value and the detection of limit were 1.96 mg/L and 0.179 mg/L, respectively, as shown in the standard curve. The tracers of PBM-EDF 2 and 3, which were chased from 4 PBM-EDF tracers, exhibited the good standard curves based on the MAb AZI-110. The FPIA constructed to analyze the azinphos-methyl showed the IC50 1.003 mg/L and detection limit 0.955 mg/L when PBM-EDF 2 was employed and the IC50 0.1487 mg/L and detection limit 0.150 mg/L were obtained when PBM-EDF 3 was used.

An immunoaffinity chromatography column was developed to remove diazinon from water and soil samples. In this paper, two types of absorbent columns, the immunoaffinity chromatography column and the ENVI-Carb column, were compared. To accomplish this, each of these columns was used to treat water and soil samples that had been spiked with diazinon at concentrations of 2.5 or 5 ng/mL (or ng/g). High performance liquid chromatography was then used to analyze the treated samples. The ENVI-Carb column recovered 87.99%-95.95% of the diazinon from water and soil with CVs of 5.08%-8.06%. The recoveries observed when the immunoaffinity chromatography column was used were slightly lower (52.61%-81.58%); however, it effectively clean up the soil samples.

FGFRs are considered essential targets for cancer therapy. We previously reported that msFGFR2c, a Ser252Trp mutant soluble ectodomain of FGFR2IIIc, inhibited tumor growth by blocking FGF signaling pathway. However, the underlying molecular mechanism is still obscure. In this study, we reported that msFGFR2c but not wild-type soluble ectodomain of FGFR2IIIc (wsFGFR2c) could selectively bind to c subtype of FGFRs in the presence of FGF-2. Thermodynamic analysis demonstrated that msFGFR2c bound to wsFGFR2c in the presence of FGF-2 with a K value of 6.61 × 105 M−1. Molecular dynamics simulations revealed that the mutated residue Trp252 of msFGFR2c preferred a π-π interaction with His254 of wsFGFR2c. Concomitantly, Arg255 of msFGFR2c and Glu250 of wsFGFR2c adjusted their conformations and formed three H-bonds. These two interactions therefore stabilized the final structure of wsFGFR2c and msFGFR2c heterocomplex. In FGFR2IIIc-positive/high FGF-2-secreted BT-549 cells, msFGFR2c significantly inhibited the proliferation and induced apoptosis by the blockage of FGF-2-activated FGFRs phosphorylation, also the growth and angiogenesis of its xenograft tumors implanted in chick embryo chorioallantoic membrane model. While weaker the above inhibitory effects of msFGFR2c were observed on FGFR2IIIc-negative/low FGF-2-secreted MCF-7 and MDA-MB-231 cell lines in vitro and in vivo. Moreover, msFGFR2c significantly inhibited the proliferation of FGFR1IIIc-positive NCI-H1299 lung cancer cells by the suppression of FGF-2-induced FGFR1 activation and suppressed the growth of NCI-H1299 transplanted tumors in nude mice. In sum, msFGFR2c is a potential anti-tumor agent targeting FGFR2c/FGFR1c-positive tumor cells. These findings also provide a molecular basis for msFGFR2c to disrupt the activation of FGF signaling.

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