The Role of Resveratrol in Cancer Therapy

Ko, Jeong-Hyeon,Sethi, Gautam,Um, Jae-Young,Shanmugam, Muthu K,Arfuso, Frank,Kumar, Alan Prem,Bishayee, Anupam,Ahn, Kwang Seok MDPI 2017 INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES Vol.18 No.12

<P>Natural product compounds have recently attracted significant attention from the scientific community for their potent effects against inflammation-driven diseases, including cancer. A significant amount of research, including preclinical, clinical, and epidemiological studies, has indicated that dietary consumption of polyphenols, found at high levels in cereals, pulses, vegetables, and fruits, may prevent the evolution of an array of diseases, including cancer. Cancer development is a carefully orchestrated progression where normal cells acquires mutations in their genetic makeup, which cause the cells to continuously grow, colonize, and metastasize to other organs such as the liver, lungs, colon, and brain. Compounds that modulate these oncogenic processes can be considered as potential anti-cancer agents that may ultimately make it to clinical application. Resveratrol, a natural stilbene and a non-flavonoid polyphenol, is a phytoestrogen that possesses anti-oxidant, anti-inflammatory, cardioprotective, and anti-cancer properties. It has been reported that resveratrol can reverse multidrug resistance in cancer cells, and, when used in combination with clinically used drugs, it can sensitize cancer cells to standard chemotherapeutic agents. Several novel analogs of resveratrol have been developed with improved anti-cancer activity, bioavailability, and pharmacokinetic profile. The current focus of this review is resveratrol’s in vivo and in vitro effects in a variety of cancers, and intracellular molecular targets modulated by this polyphenol. This is also accompanied by a comprehensive update of the various clinical trials that have demonstrated it to be a promising therapeutic and chemopreventive agent.</P>

Thermo-sensitive Electrospun Fibrous Magnetic Composite Sheets

Jungsu Choi,Jinu Kim,Heejae Yang,Frank K. Ko,Ki Hyeon Kim 한국자기학회 2015 Journal of Magnetics Vol.20 No.3

The PVDF fibrous composite filled with iron oxide nanoparticles were prepared by using the electrospinning technique. The electrospun composite have the thickness in the range of 60-80 μm with the average fibrous diameters of 500-900 nm. The magnetizations of PVDF fibrous composite filled with iron oxide nanoparticles showed 4.5 emu/g, 3.1 emu/g and 1.6 emu/g at 1.5 T of external magnetic field for 20 wt.%, 10 wt.% and 5 wt.% iron oxide nanoparticles, respectively. The heat elevation of the magnetic composite were measured under various AC magnetic fields, frequency and the ambient temperatures. The temperature reached up to 46.3℃ from 36oC at 128 Oe and 355 kHz for 20 wt.% iron oxide nanoparticles filled in PVDF fibrous composite sheet. The specific absorption rate of theses sheets increased from 0.041 W/g to 0.236 W/g with the increment of AC magnetic field from 90 Oe to 167 Oe at 190 kHz, respectively.

Palladium-Zeolite nanofiber as an effective recyclable catalyst membrane for water treatment

Choi, Jungsu,Chan, Sophia,Yip, Garriott,Joo, Hyunjong,Yang, Heejae,Ko, Frank K. Elsevier 2016 Water research Vol.101 No.-

<P><B>Abstract</B></P> <P>Zeolite is an exciting natural material due to its unique capability of ammonium nitrogen (NH<SUB>3</SUB> N) adsorption in water. In this study, multifunctional hybrid composites of zeolite/palladium (Ze/Pd) on polymer nanofiber membranes were fabricated and explored for sustainable contaminant removal. SEM and XRD demonstrated that zeolite and palladium nanoparticles were uniformly distributed and deposited on the nanofibers. NH<SUB>3</SUB> N recovery rate was increased from 23 to 92% when palladium coated zeolite was embedded on the nanofiber. Multifunctional nanofibers of Ze/Pd membranes were able to adsorb NH<SUB>3</SUB> N on the zeolites placed on the surface of fibers and palladium catalysts were capable of selective oxidation of NH<SUB>3</SUB> N to N<SUB>2</SUB> gas. The cycling of NH<SUB>3</SUB> N adsorption-oxidation, high flux, hydrophilicity, and flexibility of the membrane makes it a strong candidate for water treatment.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Zeolite and palladium nanoparticles were uniformly deposited on the nanofibers. </LI> <LI> Palladium catalysts were capable of selective oxidation of NH<SUB>3</SUB> N to N<SUB>2</SUB> gas. </LI> <LI> Multifunctional nanofibrous membranes were able to absorb and remove NH<SUB>3</SUB> N. </LI> <LI> Ze/Pd nanofiber membrane can be recycled and reused for NH<SUB>3</SUB> N removal. </LI> <LI> Recovery rate of Ze/Pd membranes functions were shown to be 92.2% at 250 °C. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Three-dimensional (3D) palladium-zinc oxide nanowire nanofiber as photo-catalyst for water treatment

Choi, Jungsu,Chan, Sophia,Joo, Hyunjong,Yang, Heejae,Ko, Frank K. Elsevier 2016 Water research Vol.101 No.-

<P><B>Abstract</B></P> <P>Zinc Oxide Nano Wires (ZNWs) has been considered as a promising material for purification and disinfection of water and remediation of hazardous waste owing to its high activity and lower cost. In this study, three-dimensional (3D) structured palladium (Pd)/ZNWs were synthesized on the fabricated electrospun nanofibers and explored for enhancement of organic matter (OM) removal efficiency in water by suppressing electron–hole recombination during photocatalytic activity and increased surface area. The densely populated ZNWs were fabricated on the electrospun nanofiber by electroless plating (EP) and hydrothermal synthesis. In order to improve photocatalytic efficiency, a thin layer of Pd was coated prior to ZNWs growth to induce suppression of electron hole recombination produced during catalyst activity. The creation of a highly porous network of nanofibers decorated with ZNWs resulted in an increase of specific removal rate (SRR) of OM from 0.0249 to 0.0377 mg COD<SUB>Cr</SUB> removed/mg ZNWs-hr when ZNW were grown on a Pd layer. It is believed that the demonstration of OM removal in the water through Pd/ZNWs membrane and enhanced photocatalytic activity under UV irradiation from layered structure can broaden potential applicability of Pd/ZNWs membranes for various photo catalytic water treatment.</P> <P><B>Highlights</B></P> <P> <UL> <LI> 3D structured ZNWs were uniformly grown on the palladium coated nanofibers. </LI> <LI> Enhancement of OM removal through suppressing electron hole recombination. </LI> <LI> Removal of OM was found to be 96.6% from the Pd/ZNWs nanofiber. </LI> <LI> Pd/ZNWs membrane provide a powerful photocatalyst process for water treatment. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Structure and properties of graphene oxide/cellulose hybrid fibers via divalent metal ions treatment

Ryu, Jisu,Lim, Jin Seong,Ahn, Seokhoon,Jo, Seong Mu,Ko, Frank K.,Lee, Joong Hee,Hwang, Jun Yeon Springer-Verlag 2018 Cellulose Vol.25 No.1

<P>Cellulose hybrid fibers (CeHFs), hybridized via graphene oxide (GO) and metal ions (Ca2+), are synthesized by dry-jet wet spinning. The synthesized GO-Ca2+-CeHFs exhibit the tensile strength and the breaking elongation of 551 +/- 37.5 MPa and 5.9 +/- 0.4%, respectively, while the GO/cellulose composite fibers (GO-CeFs) show the tensile strength of 403 +/- 76.0 MPa and the elongation of 4.5 +/- 0.5%; thus, the GO-Ca2+-CeHFs demonstrate improved mechanical properties over GO-CeFs by 37 and 31% in terms of tensile strength and elongation, respectively. These results are attributed to the metal ions that form a good interfacial interaction between the functional groups of cellulose and GO. In addition, the tensile strength of GO-Ba2+-CeHFs is as high as 580 +/- 25 MPa, which is induced by the difference in the ionic radius. Therefore, the high mechanical properties of the synthesized cellulose-based fibers have the potential to be used as sustainable alternative to the synthetic fibers used in the industrial applications.</P>