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.

Compositional homogeneity and X-ray topographic analyses of CdTe_<i>x</i>Se_1−<i>x</i> grown by the vertical Bridgman technique

Roy, U.N.,Bolotnikov, A.E.,Camarda, G.S.,Cui, Y.,Hossain, A.,Lee, K.,Lee, W.,Tappero, R.,Yang, Ge,Cui, Y.,Burger, A.,James, R.B. Elsevier 2015 Journal of crystal growth Vol.411 No.-

<P><B>Abstract</B></P> <P>We grew CdTe<SUB> <I>x</I> </SUB>Se<SUB>1−<I>x</I> </SUB> crystals with nominal Se concentrations of 5%, 7%, and 10% by the vertical Bridgman technique, and evaluated their compositional homogeneity and structural quality at the NSLS’ X-ray fluorescence and white beam X-ray topography beam lines. Both X-ray fluorescence and photoluminescence mapping revealed very high compositional homogeneity of the CdTe<SUB> <I>x</I> </SUB>Se<SUB>1−<I>x</I> </SUB> crystals. We noted that those crystals with higher concentrations of Se were more prone to twinning than those with a lower content. The crystals were fairly free from strains and contained low concentrations of sub-grain boundaries and their networks.</P> <P><B>Highlights</B></P> <P> <UL> <LI> CdTeSe crystals were grown by the vertical Bridgman technique. </LI> <LI> Very high compositional homogeneity. </LI> <LI> Low concentration of sub-grain boundaries. </LI> <LI> Almost free from sub-grain boundary network. </LI> </UL> </P>

Nitrate-Containing Beetroot Juice Reduces Oxygen Consumption During Submaximal Exercise in Low but Not High Aerobically Fit Male Runners

( Colin R. Carriker ),( Roger A. Vaughan ),( Trisha A. Vandusseldorp ),( Kelly E. Johnson ),( Nicholas M. Beltz ),( James J. Mccormick ),( Nathan H. Cole ),( Ann L. Gibson ) 한국운동영양학회 2016 Physical Activity and Nutrition (Phys Act Nutr) Vol.20 No.4

[Purpose] To examine the effect of a 4-day NO₃- loading protocol on the submaximal oxygen cost of both low fit and high fit participants at five different exercise intensities. [Methods] Eleven (6 high fit, VO_2max 60.1 ± 4.6ml/kg/min; 5 low fit, VO_2max 42.4 ± 3.2ml/ kg/min) participants were initially assigned to a placebo (PL; negligible NO₃-) or inorganic nitrate-rich (NR; 6.2 mmol nitrate/day) group using a double-blind, placebo-controlled, crossover design. Participants completed three trials (T1, T2 and T3). T1 included a maximal aerobic capacity (VO_2max) treadmill test. A 6-day washout, minimizing nitrate consumption, preceded T2. Each of the four days prior to T2 and T3, participants consumed either PL or NR with the final dose 2.5 hours prior to exercise. A 14-day washout followed T2. T2 and T3 consisted of 5-minute submaximal treadmill bouts (45, 60, 70, 80 and 85% VO_2max) determined during T1. [Results] Low fit nitrate-supplemented participants consumed less oxygen (p<0.05) at lower workloads (45% and 60% VO_2max) compared to placebo trials; changes were not observed in high fit participants. The two lowest intensity workloads of 45 and 60% VO_2max revealed the greatest correlation (r=0.54, p=0.09 and r=0.79, p<0.05; respectively) between VO_2max and change in oxygen consumption. No differences were found between conditions for heart rate, respiratory exchange ratio or rating of perceived exertion for either fitness group. [Conclusion] Nitrate consumption promotes reduced oxygen consumption at lower exercise intensities in low fit, but not high fit males. Lesser fit individuals may receive greater benefit than higher fit participants exercising at intensities <60% VO_2max.

Persistent near-tropical warmth on the Antarctic continent during the early Eocene epoch

Pross, J철rg,Contreras, Lineth,Bijl, Peter K.,Greenwood, David R.,Bohaty, Steven M.,Schouten, Stefan,Bendle, James A.,R철hl, Ursula,Tauxe, Lisa,Raine, J. Ian,Huck, Claire E.,van de Flierdt, Tina,Jamieso Nature Publishing Group, a division of Macmillan P 2012 Nature Vol.488 No.7409

The warmest global climates of the past 65 million years occurred during the early Eocene epoch (about 55 to 48 million years ago), when the Equator-to-pole temperature gradients were much smaller than today and atmospheric carbon dioxide levels were in excess of one thousand parts per million by volume. Recently the early Eocene has received considerable interest because it may provide insight into the response of Earth??s climate and biosphere to the high atmospheric carbon dioxide levels that are expected in the near future as a consequence of unabated anthropogenic carbon emissions. Climatic conditions of the early Eocene ??greenhouse world??, however, are poorly constrained in critical regions, particularly Antarctica. Here we present a well-dated record of early Eocene climate on Antarctica from an ocean sediment core recovered off the Wilkes Land coast of East Antarctica. The information from biotic climate proxies (pollen and spores) and independent organic geochemical climate proxies (indices based on branched tetraether lipids) yields quantitative, seasonal temperature reconstructions for the early Eocene greenhouse world on Antarctica. We show that the climate in lowland settings along the Wilkes Land coast (at a palaeolatitude of about 70째 south) supported the growth of highly diverse, near-tropical forests characterized by mesothermal to megathermal floral elements including palms and Bombacoideae. Notably, winters were extremely mild (warmer than 10??째C) and essentially frost-free despite polar darkness, which provides a critical new constraint for the validation of climate models and for understanding the response of high-latitude terrestrial ecosystems to increased carbon dioxide forcing.

Methods for sampling and analysis of marine microalgae in ship ballast tanks: a case study from Tampa Bay, Florida, USA

Matthew J. Garrett,R. William Richardson,Jennifer L. Wolny,B. James Williams,Michael D. Dirks,Julie A. Brame 한국조류학회I 2011 ALGAE Vol.26 No.2

Ballasting and deballasting of shipping vessels in foreign ports have been reported worldwide as a vector of introduction of non-native aquatic plants and animals. Recently, attention has turned to ballast water as a factor in the global increase of harmful algal blooms (HABs). Many species of microalgae, including harmful dinoflagellate species, can remain viable for months in dormant benthic stages (cysts) in ballast sediments. Over a period of four years, we surveyed ballast water and sediment of ships docked in two ports of Tampa Bay, Florida, USA. Sampling conditions encountered while sampling ballast water and sediments were vastly different between vessels. Since no single sample collection protocol could be applied, existing methods for sampling ballast were modified and new methods created to reduce time and labor necessary for the collection of high-quality, qualitative samples. Five methods were refined or developed,including one that allowed for a directed intake of water and sediments. From 63 samples, 1,633 dinoflagellate cysts and cyst-like cells were recovered. A native, cyst-forming, harmful dinoflagellate, Alexandrium balechii (Steidinger) F. J. R. Taylor, was collected, isolated, and cultured from the same vessel six months apart, indicating that ships exchanging ballast water in Tampa Bay have the potential to transport HAB species to other ports with similar ecologies, exposing them to non-native, potentially toxic blooms.

Methods for sampling and analysis of marine microalgae in ship ballast tanks: a case study from Tampa Bay, Florida, USA

Garrett, Matthew J.,Wolny, Jennifer L.,Williams, B. James,Dirks, Michael D.,Brame, Julie A.,Richardson, R. William The Korean Society of Phycology 2011 ALGAE Vol.26 No.2

Ballasting and deballasting of shipping vessels in foreign ports have been reported worldwide as a vector of introduction of non-native aquatic plants and animals. Recently, attention has turned to ballast water as a factor in the global increase of harmful algal blooms (HABs). Many species of microalgae, including harmful dinoflagellate species, can remain viable for months in dormant benthic stages (cysts) in ballast sediments. Over a period of four years, we surveyed ballast water and sediment of ships docked in two ports of Tampa Bay, Florida, USA. Sampling conditions encountered while sampling ballast water and sediments were vastly different between vessels. Since no single sample collection protocol could be applied, existing methods for sampling ballast were modified and new methods created to reduce time and labor necessary for the collection of high-quality, qualitative samples. Five methods were refined or developed, including one that allowed for a directed intake of water and sediments. From 63 samples, 1,633 dinoflagellate cysts and cyst-like cells were recovered. A native, cyst-forming, harmful dinoflagellate, Alexandrium balechii (Steidinger) F. J. R. Taylor, was collected, isolated, and cultured from the same vessel six months apart, indicating that ships exchanging ballast water in Tampa Bay have the potential to transport HAB species to other ports with similar ecologies, exposing them to non-native, potentially toxic blooms.

Overcoming Zn segregation in CdZnTe with the temperature gradient annealing

Kim, K.,Bolotnikov, A.E.,Camarda, G.S.,Hossain, A.,James, R.B. Elsevier 2016 Journal of crystal growth Vol.442 No.-

<P><B>Abstract</B></P> <P>The availability of large volume crystals with the same energy gap in melt-grown CdZnTe (CZT) is restricted due to the Zn segregation in CdTe hosts. We observed the migration of Zn in the solid phase along the positive temperature gradient direction both <I>in situ</I> and post-growth temperature gradient annealing (TGA) of CZT. Diffusivity of Zn obtained from the <I>in situ</I> TGA was approximately 10<SUP>−5</SUP> cm<SUP>2</SUP>/s order and completely different mechanism with that of post-growth. The CZT ingots obtained through <I>in situ</I> TGA have uniform Zn and resistivity of <SUP> 10 10 </SUP> Ω cm orders. The CZT detectors fabricated from <I>in situ</I> TGA applied ingots exhibit 10% of energy resolution for 59.5keV peak of <SUP>241</SUP>Am.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Zn migrates in the solid phase along the positive temperature gradient. </LI> <LI> Zn migration mechanism is different in <I>in situ</I> and post-growth CdZnTe annealing. </LI> <LI> Zn segregation in CdZnTe can be solved by temperature gradient annealing. </LI> <LI> <I>In situ</I> CdZnTe annealing is a useful method to obtain highly uniform bandgap detector. </LI> </UL> </P>

Multiwavelength Analysis of the Merging Galaxy Cluster A115

Kim, Mincheol,Jee, M. James,Finner, Kyle,Golovich, Nathan,Wittman, David M.,Weeren, R. J. van,Dawson, W. A. American Astronomical Society 2019 The Astrophysical journal Vol.874 No.2

The <i>Ink4a/Arf</i> Locus Is a Barrier to Direct Neuronal Transdifferentiation

Price, James D.,Park, Ki-Youb,Chen, Jiadong,Salinas, Ryan D.,Cho, Mathew J.,Kriegstein, Arnold R.,Lim, Daniel A. Society for Neuroscience 2014 The Journal of neuroscience Vol.34 No.37

<P>Non-neurogenic cell types, such as cortical astroglia and fibroblasts, can be directly converted into neurons by the overexpression of defined transcription factors. Normally, the cellular phenotype of such differentiated cells is remarkably stable and resists direct cell transdifferentiation. Here we show that the <I>Ink4a/Arf</I> (also known as <I>Cdkn2a</I>) locus is a developmental barrier to direct neuronal transdifferentiation induced by transcription factor overexpression. With serial passage <I>in vitro</I>, wild-type postnatal cortical astroglia become progressively resistant to <I>Dlx2</I>-induced neuronal transdifferentiation. In contrast, the neurogenic competence of <I>Ink4a/Arf</I>-deficient astroglia is both greatly increased and does not diminish through serial cell culture passage. Electrophysiological analysis further demonstrates the neuronal identity of cells induced from <I>Ink4a/Arf-</I>null astroglia, and short hairpin RNA-mediated acute knockdown of p16Ink4a and p19Arf p16<SUP>Ink4a</SUP> and p19<SUP>Arf</SUP> indicates that these gene products function postnatally as a barrier to cellular transdifferentiation. Finally, we found that mouse fibroblasts deficient for <I>Ink4a/Arf</I> also exhibit greatly enhanced transcription factor-induced neuronal induction. These data indicate that <I>Ink4a/Arf</I> is a potent barrier to direct neuronal transdifferentiation and further suggest that this locus functions normally in the progressive developmental restriction of postnatal astrocytes.</P>

A Vocabulary Frequency Analysis of a TESOL Certificate Course

James R. Brawn,David A. Leaper 한국응용언어학회 2014 응용 언어학 Vol.30 No.2

This paper reports on a study that established the vocabulary coverage required for the reading materials in a TESOL Certificate course in Korea and compared it to the vocabulary knowledge of its participants. A corpus of 570,000 words was formed from the eight required readings of the course and were then analyzed using Nation’s (2006) list of the 14,000 most common word families. The corpus reached the 95% and 98% thresholds in the 3000 and 6000 most frequent word bands respectively, although it varied somewhat according to the text. The knowledge of participants’ vocabulary was assessed by a vocabulary size test, and was found to be mostly sufficient for the 95% threshold. The implications of investigating course difficulty through vocabulary frequency and the assessment of participants’ vocabulary knowledge are discussed in relation to the reading purposes of a TESOL certificate program.