Mouse Pulmonary Cytochrome P-450 Naphthalene Hydroxylase : cDNA Cloning, Sequence, and Expression in Saccharomyces cerevisiae

Ritter, Joseph K.,Owens, Ida S.,Negishi, Masahiko,Nagata, Kiyoshi,Sheen, Yhun Y.,Gillette, James R.,Sasame, Henry A. 이화여자대학교 생명과학연구소 1991 생명과학연구논문집 Vol.2 No.-

We have isolated a cDNA clone, Nah-2, encoding the cytochrome P-450^Nah(naphthalene hydroxylase) from a mouse lung λZAP cDNA library using anti-cytochrome P-450^Nah IgG as a probe. This same antibody selectively blocked[Nagata, K.,Martin, B. M., Gillette, J. R., & Sasame, H. A.(1990) Drug Metab. Dispos. 18, 557-564] the cytochrome P-450 in mouse lung microsomes that catalyzed the conversion of naphthalene to (1R,2S)- naphthalene 1,2-oxide, which has been postulated as a causative agent in the naphthalene-induced tissue-specific necrosis of Clara cells in mouse lung. The toxic effect is seen in mouse and not in rat. The cDNA encodes a polypeptide of 491 amino acids with a molecular mass of 50 kDa. Northern blot analysis with an Nah-2specific probe revealed that the mRNA is expressed in a species-and tissue-specific manner, present only in mouse lung and liver and not in that of rat. The mRNA encoding Nah-2 is constitutively expressed and is not induced by either phenobarbital, pyrazole, pregnenolone 16∂-carbonitrile, or 3-methylcholanthrene. Comparative amino acid sequence analyses with other documented members of the P-450 gene superfamily revealed that this encoded protein is in the IIF subfamily. To analyze its substrate specificity, the cDNA was inserted into the vector, pAAH5, and expressed in the Saccharonyces cerevisiae strain, AH_22. The presence of cytochrome P-450_Nah in the micreosomes isolated from transformed cell and analyzed by Western blot was confirmed by immunocomplexing product with anti-cytochrome P450_Nah IgG. Furthermore, activity toward naphthalene in the microsomes from the transformed cells established that this clone encodes a naphthalene hydroxylase. Like lung microsomes and purified and reconstituted cytochrome P450_Nah, transformed yeast microsomes convert naphthalene primarily to the trans-(1R)-hydroxy-(2R)-glutathionyl-1, 2-dihydronaphthalene conjugate, a stable form of the putative toxicant(1R,2S) oxide in the presence of glutathione and a mixture of glutathione S-transferases. Results of immunochemical studies support a role of this cytochrome P-450 in lung toxicity in mice exposed to high doses of naphthalene.

Highly flexible pseudocapacitor based on freestanding heterogeneous MnO₂/conductive polymer nanowire arrays

Duay, Jonathon,Gillette, Eleanor,Liu, Ran,Lee, Sang Bok The Royal Society of Chemistry 2012 Physical chemistry chemical physics Vol.14 No.10

<P>Flexible electronics such as wearable electronic clothing, paper-like electronic devices, and flexible biomedical diagnostic devices are expected to be commercialized in the near future. Flexible energy storage will be needed to power these devices. Supercapacitor devices based on freestanding nanowire arrays are promising high power sources for these flexible electronics. Electrodes for these supercapacitor devices consisting of heterogeneous coaxial nanowires of poly (3,4-ethylenedioxythiophene) (PEDOT)-shell and MnO<SUB>2</SUB>-core materials have been shown in a half cell system to have improved capacitance and rate capabilities when compared to their pure nanomaterials; however, their performance in a full cell system has not been fully investigated. Herein, these coaxial nanowires are tested in both a symmetric and an asymmetric (utilizing a PEDOT nanowire anode) full cell configuration in the aspect of charge storage, charge rate, and flexibility without using any carbon additives and polymer binders. It is found that the asymmetric cell outperforms the symmetric cell in terms of energy density, rate capability, and cycle ability. The asymmetric device's electrode materials display an energy density of 9.8 Wh/kg even at a high power density of 850 W kg<SUP>−1</SUP>. This device is highly flexible and shows fast charging and discharging while still maintaining 86% of its energy density even under a highly flexed state. The total device is shown to have a total capacitance of 0.26 F at a maximum voltage of 1.7 V, which is capable of providing enough energy to power small portable devices.</P> <P>Graphic Abstract</P><P>Highly flexible supercapacitor device using MnO<SUB>2</SUB>/conductive polymer coaxial nanowire arrays with a practical capacitance of 0.26 F at a voltage of 1.7 V. <IMG SRC='http://pubs.rsc.org/services/images/RSCpubs.ePlatform.Service.FreeContent.ImageService.svc/ImageService/image/GA?id=c2cp00019a'> </P>

Anodized pore structural evolution of focused ion beam patterned Al: direct analysis of branched nanopores and nanosacks

Lee, Sunhee,Kim, Dongheun,Gillette, Eleanor,Oh, Jihun,Han, Sang Woo,Lee, Sang Bok The Royal Society of Chemistry 2013 Physical chemistry chemical physics Vol.15 No.26

<P>In this work we describe three different trends of pore growth for anodic aluminum oxide nanopores based on their dependence on prepatterned interpore distances. Nanopatterned hexagonal concave arrays were formed by focused ion beam (FIB) lithography on aluminum foil with interpore distances in the range of 100 to 240 nm and the Al foil was anodized under the standard conditions known to result in a 100 nm interpore distance. This method allowed a systematic investigation of pore formation under the non-equilibrium conditions created by the FIB prepatterning. The pore diameter and the pore growth direction, which are affected by the interpore distance, were measured by scanning electron microscopy (SEM) and transmission electron microscopy (TEM) analysis with ion milling. When the interpore distance increases from 100 to 140 nm, the pore diameter becomes larger and nanopores are slightly tilted but maintained the interpore distance and straightness. As the interpore distance increases from 150 to 180 nm, the pore diameter becomes smaller and each nanopore starts to split into two nanopores. At interpore distances of over 190 nm, prepatterned concaves are developed into round flask-shaped nanosacks instead of one-dimensional tubes, and then these are split into three more sub-nanopores. The fundamental characteristics of anodic aluminum oxidation are discussed in accordance with various prepatterned concaves in the nanopore growth processes, providing a rational theory for the design of various complex 3-D AAO structures that can be controlled by prepatterning.</P> <P>Graphic Abstract</P><P>A detailed analysis of FIB-imprinted anodized aluminium oxide provides insight into 3-D structure formation in three distinct ordering regimes. <IMG SRC='http://pubs.rsc.org/services/images/RSCpubs.ePlatform.Service.FreeContent.ImageService.svc/ImageService/image/GA?id=c3cp50630d'> </P>

Self-Limiting Electrodeposition of Hierarchical MnO₂ and M(OH)₂/MnO₂ Nanofibril/Nanowires: Mechanism and Supercapacitor Properties

Duay, Jonathon,Sherrill, Stefanie A.,Gui, Zhe,Gillette, Eleanor,Lee, Sang Bok American Chemical Society 2013 ACS NANO Vol.7 No.2

<P>Hierarchical nanostructures have generated great interest in the energy, materials, and chemical sciences due to the synergic properties of their composite architectures. Herein, a hierarchical MnO<SUB>2</SUB> nanofibril/nanowire array is successfully synthesized. The structure consists of a conformal layer of MnO<SUB>2</SUB> nanofibrils evenly distributed on the surface of the individual MnO<SUB>2</SUB> nanowires. The synthetic mechanism of this hierarchical structure is characterized by electrochemical measurements, Raman spectroscopy, EELS, and electron microscopy. This material was then investigated at slow scan rates for its charge storage mechanisms in different solvents. In aqueous electrolyte, the nanofibrils show a capacitance almost purely dedicated to double-layer and surface adsorption processes, while in an acetonitrile electrolyte, the nanofibrils’ capacitance comes mainly from a cation insertion process. This material was also tested at high scan rates in aqueous solution for its practical supercapacitor capabilities. The material shows a large capacitance of 298 F/g at 50 mV/s and 174 F/g at 250 mV/s. It also maintains 85.2% of its capacitance after 1000 cycles. The material also displays easily controllable parameters such as nanowire length, nanowire diameter, and amount of nanofibril material which is shown here to affect the capacitance dramatically.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/ancac3/2013/ancac3.2013.7.issue-2/nn3056077/production/images/medium/nn-2012-056077_0014.gif'></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/nn3056077'>ACS Electronic Supporting Info</A></P>

Environmental Mercury and Its Toxic Effects

Rice, Kevin M.,Walker, Ernest M. Jr.,Wu, Miaozong,Gillette, Chris,Blough, Eric R. The Korean Society for Preventive Medicine 2014 Journal of Preventive Medicine and Public Health Vol.47 No.2

Mercury exists naturally and as a man-made contaminant. The release of processed mercury can lead to a progressive increase in the amount of atmospheric mercury, which enters the atmospheric-soil-water distribution cycles where it can remain in circulation for years. Mercury poisoning is the result of exposure to mercury or mercury compounds resulting in various toxic effects depend on its chemical form and route of exposure. The major route of human exposure to methylmercury (MeHg) is largely through eating contaminated fish, seafood, and wildlife which have been exposed to mercury through ingestion of contaminated lower organisms. MeHg toxicity is associated with nervous system damage in adults and impaired neurological development in infants and children. Ingested mercury may undergo bioaccumulation leading to progressive increases in body burdens. This review addresses the systemic pathophysiology of individual organ systems associated with mercury poisoning. Mercury has profound cellular, cardiovascular, hematological, pulmonary, renal, immunological, neurological, endocrine, reproductive, and embryonic toxicological effects.

Static and transient analyses of Advanced Power Reactor 1400 (APR1400) initial core using open-source nodal core simulator KOMODO

Jwaher Alnaqbi,Donny Hartanto,Reem Alnuaimi,Muhammad Imron,Victor Gillette 한국원자력학회 2022 Nuclear Engineering and Technology Vol.54 No.2

The United Arab Emirates is currently building and operating four units of the APR-1400 developed by aSouth Korean vendor, Korea Electric Power Corporation (KEPCO). This paper attempts to perform APR1400 reactor core analysis by using the well-known two-step method. The two-step method wasapplied to the APR-1400 first cycle using the open-source nodal diffusion code, KOMODO. In this study,the group constants were generated using CASMO-4 fuel transport lattice code. The simulation wasperformed in Hot Zero Power (HZP) at steady-state and transient conditions. Some typical parametersnecessary for the Nuclear Design Report (NDR) were evaluated in this paper, such as effective neutronmultiplication factor, control rod worth, and critical boron concentration for steady-state analysis. Otherparameters such as reactivity insertion, power, and fuel temperature changes during the ReactivityInsertion Accident (RIA) simulation were evaluated as well. The results from KOMODO were verifiedusing PARCS and SIMULATE-3 nodal core simulators. It was found that KOMODO gives an excellentagreement

Environmental Mercury and Its Toxic Effects

Kevin M. Rice,Ernest M. Walker Jr,Miaozong Wu,Chris Gillette,Eric R. Blough 대한예방의학회 2014 Journal of Preventive Medicine and Public Health Vol.47 No.2

Mercury exists naturally and as a man-made contaminant. The release of processed mercury can lead to a progressive increase in the amount of atmospheric mercury, which enters the atmospheric-soil-water distribution cycles where it can remain in circulation for years. Mercury poisoning is the result of exposure to mercury or mercury compounds resulting in various toxic effects depend on its chemical form and route of exposure. The major route of human exposure to methylmercury (MeHg) is largely through eating contaminated fish, seafood, and wildlife which have been exposed to mercury through ingestion of contaminated lower organisms. MeHg toxicity is associated with nervous system damage in adults and impaired neurological development in infants and children. Ingested mercury may undergo bioaccumulation leading to progressive increases in body burdens. This review addresses the systemic pathophysiologyof individual organ systems associated with mercury poisoning. Mercury has profound cellular, cardiovascular, hematological, pulmonary, renal, immunological, neurological, endocrine, reproductive, and embryonic toxicological effects.

Active Antioxidizing Particles for On-Demand Pressure-Driven Molecular Release

Seo, Yongbeom,Leong, Jiayu,Teo, Jye Yng,Mitchell, Jennifer W.,Gillette, Martha U.,Han, Bumsoo,Lee, Jonghwi,Kong, Hyunjoon American Chemical Society 2017 ACS APPLIED MATERIALS & INTERFACES Vol.9 No.41

<P>Overproduced reactive oxygen species (ROS) are closely related to various health problems including inflammation, infection, and cancer. Abnormally high ROS levels can cause serious oxidative damage to biomolecules, cells, and tissues. A series of nano- or microsized particles has been developed to reduce the oxidative stress level by delivering antioxidant drugs. However, most systems are often plagued by slow molecular discharge, driven by diffusion. Herein, this study demonstrates the polymeric particles whose internal pressure can increase upon exposure to H2O2, one of the ROS, and in turn, discharge antioxidants actively. The on-demand pressurized particles are assembled by simultaneously encapsulating water-dispersible manganese oxide (MnO2) nanosheets and green tea derived epigallocatechin gallate (EGCG) molecules into a poly(lactic-co-glycolic acid) (PLGA) spherical shell. In the presence of H2O2, the MnO2 nanosheets in the PLGA particle generate oxygen gas by decomposing H2O2 and increase the internal pressure. The pressurized PLGA particles release antioxidative EGCG actively and, in turn, protect vascular and brain tissues from oxidative damage more effectively than the particles without MnO2 nanosheets. This H2O2 responsive, self-pressurizing particle system would be useful to deliver a wide array of molecular cargos in response to the oxidation level.</P>

Glacier Moraine Formation-Mimicking Colloidal Particle Assembly in Microchanneled, Bioactive Hydrogel for Guided Vascular Network Construction

Lee, Min Kyung,Rich, Max H.,Shkumatov, Artem,Jeong, Jae Hyun,Boppart, Marni D.,Bashir, Rashid,Gillette, Martha U.,Lee, Jonghwi,Kong, Hyunjoon Wiley (John WileySons) 2015 Advanced Healthcare Materials Vol.4 No.2

<P>This study demonstrates that a new method to align microparticles releasing bioactive molecules in microchannels of a hydrogel allows the guiding of growth direction and spacing of vascular networks.</P>

Hydrogels: Glacier Moraine Formation-Mimicking Colloidal Particle Assembly in Microchanneled, Bioactive Hydrogel for Guided Vascular Network Construction (Adv. Healthcare Mater. 2/2015)

Lee, Min Kyung,Rich, Max H.,Shkumatov, Artem,Jeong, Jae Hyun,Boppart, Marni D.,Bashir, Rashid,Gillette, Martha U.,Lee, Jonghwi,Kong, Hyunjoon Wiley (John WileySons) 2015 Advanced Healthcare Materials Vol.4 No.2