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Sultan M.T.,Hallym University | Li H.-M.,Hallym University | Lee Y.Z.,ProteomeTech Inc. | Lim S.S.,Hallym University | Song D.-K.,Hallym University
Korean Journal of Physiology and Pharmacology | Year: 2016

We fortuitously observed a human neutrophil intracellular free-calcium concentration ([Ca2+]i) increasing activity in the commercially available phosphodiesterase I (PDE I), which is actually dried crude venom of Crotalus atrox. As this activity was not observed with another commercially available pure PDE I, we tried to find out the causative molecule(s) present in 'crude' PDE, and identified Lys49-phospholipase A2 (Lys49-PLA2 or K49-PLA2), a catalytically inactive protein which belongs to the phospholipase A2 family, by activity-driven three HPLC (reverse phase, size exclusion, reverse phase) steps followed by SDS-PAGE and LC-MS/MS. K49-PLA2 induced Ca2+ inf ux in human neutrophils without any cytotoxic ef ect. Two calcium channel inhibitors, 2-aminoetoxydiphenyl borate (2-APB) (30 μM) and SKF-96365 (20 μM) signif cantly inhibited K49-PLA2-induced [Ca2+]i increase. These results suggest that K49-PLA2 modulates [Ca2+]i in human neutrophils via 2-APB- and SKF-96365-sensitive calcium channels without causing membrane disruption. Copyright © Korean J Physiol Pharmacol.

Bahk Y.Y.,Yonsei University | Na B.-K.,Gyeongsang National University | Cho S.-H.,National Institute of Health | Kim J.-Y.,National Institute of Health | And 3 more authors.
Korean Journal of Parasitology | Year: 2010

Advancements in the field of proteomics have provided great opportunities for the development of diagnostic and therapeutic tools against human diseases. In this study, we analyzed haptoglobin and amyloid A protein levels of vivax malaria patients with combinations of depletion of the abundant plasma proteins, 2-dimensional gel electrophoresis (2-DE), image analysis, and mass spectrometry in the plasma between normal healthy donors and vivax malaria patients. The results showed that the expression level of haptoglobin had become significantly lower or undetectable in the plasma of vivax malaria patients due to proteolytic cleavage when compared to healthy donors on 2-DE gels. Meanwhile, serum amyloid A protein was significantly increased in vivax malaria patient's plasma with high statistical values. These 2 proteins are common acute phase reactants and further large scale evaluation with a larger number of patient's will be necessary to establish the possible clinical meaning of the existential changes of these proteins in vivax malaria patients. However, our proteomic analysis suggests the feasible values of some plasma proteins, such as haptoglobin and serum amyloid A, as associating factor candidates for vivax malaria.

Lim J.I.,Yonsei University | Lee Y.-K.,Denforus Co. | Shin J.-S.,Yonsei University | Lim K.-J.,Yonsei University | Lim K.-J.,ProteomeTech Inc.
Materials Letters | Year: 2010

To improve the mechanical properties such as flexibility and bond strength of cyanoacrylates, poly(l-lactide-co-ε-caprolactone) (PLCL) copolymers were dissolved into 2 kinds of cyanoacrylates, ethyl 2-cyanoacrylate (EC) and allyl 2-cyanoacrylate (AC). Mechanical properties such as bond strength, bending-stress recovery, and crystallization intensity were measured. The optimal concentration for high bond strength was determined to be 8% PLCL (molar ratio 70:30). EC/8% PLCL (70:30) exhibited three times higher bond strength as compared with that of EC. Further, AC/8% PLCL (50:50) exhibited better bending recovery than other materials. These results indicate that cyanoacrylate/PLCL materials can be widely used as adhesives in various fields. © 2010 Elsevier B.V. All rights reserved.

Park M.J.,Yonsei University | Min J.K.,Yonsei University | Yi S.-G.,Yonsei University | Kim J.H.,Yonsei University | And 2 more authors.
Journal of Applied Physics | Year: 2015

Near-infrared photodetectors are developed using graphene/MoS2 and WSe2/MoS2 vertical heterojunctions. These heterojunctions exhibit diode-rectifying behavior in the dark and enhanced photocurrent upon near-infrared irradiation. The photocurrent increases with increasing near-infrared power, leading to the photoresponsibility of 0.14 and 0.3 A W-1 for the graphene/MoS2 and WSe2/MoS2 heterojunctions, respectively, which are much higher than the photoresponsibility reported for a multilayer MoS2 phototransistor. © 2015 AIP Publishing LLC.

Baek J.H.,Gyeongsang National University | Lee H.J.,Yonsei University | Kim Y.H.,Kansas State University | Lim K.J.,ProteomeTech Inc. | And 2 more authors.
Pesticide Biochemistry and Physiology | Year: 2016

The whitefly Bemisia tabaci is a very destructive pest. B. tabaci is composed of various morphologically undistinguishable biotypes, among which biotypes B and Q, in particular, draw attention because of their wide distribution in Korea and differential potentials for insecticide resistance development. To develop a biotype-specific protein marker that can readily distinguishes biotypes B from other biotypes in the field, we established an ELISA protocol based on carboxylesterase 2 (COE2), which is more abundantly expressed in biotypes B compared with Q. Recombinant COE2 was expressed, purified and used for antibody construction. Polyclonal antibodies specific to B. tabaci COE2 [anti-COE2 pAb and deglycosylated anti-COE2 pAb (DG anti-COE2 pAb)] revealed a 3-9-fold higher reactivity to biotype B COE2 than biotype Q COE2 by Western blot and ELISA analyses. DG anti-COE2 pAb exhibited low non-specific activity, demonstrating its compatibility in diagnosing biotypes. Western blot and ELISA analyses determined that one of the 11 field populations examined was biotype B and the others were biotype Q, suggesting the saturation of biotype Q in Korea. DG anti-COE2 pAb discriminates B. tabaci biotypes B and Q with high specificity and accuracy and could be useful for the development of a B. tabaci biotype diagnosis kit for on-site field applications. © 2016.

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