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      • SCISCIESCOPUS

        Gα<sub>12</sub> gep oncogene deregulation of p53-responsive microRNAs promotes epithelial–mesenchymal transition of hepatocellular carcinoma

        Yang, Y M,Lee, W H,Lee, C G,An, J,Kim, E-S,Kim, S H,Lee, S-K,Lee, C H,Dhanasekaran, D N,Moon, A,Hwang, S,Lee, S J,Park, J-W,Kim, K M,Kim, S G Macmillan Publishers Limited 2015 Oncogene Vol.34 No.22

        Hepatocellular carcinoma (HCC) has a poor prognosis owing to aggressive phenotype. Gα<SUB>12</SUB> gep oncogene product couples to G-protein-coupled receptors, whose ligand levels are frequently increased in tumor microenvironments. Here, we report Gα<SUB>12</SUB> overexpression in human HCC and the resultant induction of zinc-finger E-box-binding homeobox 1 (ZEB1) as mediated by microRNA deregulation. Gα<SUB>12</SUB> expression was higher in HCC than surrounding non-tumorous tissue. Transfection of Huh7 cell with an activated mutant of Gα<SUB>12</SUB> (Gα<SUB>12</SUB>QL) deregulated microRNA (miRNA or miR)-200b/a/429, -194-2/192 and -194-1/215 clusters in the miRNome. cDNA microarray analyses disclosed the targets affected by Gα<SUB>12</SUB> gene knockout. An integrative network of miRNAs and mRNA changes enabled us to predict ZEB1 as a key molecule governed by Gα<SUB>12</SUB>. Decreases of miR-200a/b, -192 and -215 by Gα<SUB>12</SUB> caused ZEB1 induction. The ability of Gα<SUB>12</SUB> to decrease p53 levels, as a result of activating protein-1 (AP-1)/c-Jun-mediated mouse double minute 2 homolog induction, contributed to transcriptional deregulation of the miRNAs. Gα<SUB>12</SUB>QL induced ZEB1 and other epithelial–mesenchymal transition markers with fibroblastoid phenotype change. Consistently, transfection with miR-200b, -192 or -215 mimic prevented the ability of Gα<SUB>12</SUB>QL to increase tumor cell migration/invasion. In xenograft studies, sustained knockdown of Gα<SUB>12</SUB> decreased the overall growth rate and average volume of tumors derived from SK-Hep1 cell (mesenchymal-typed). In HCC patients, miR-192, -215 and/or -200a were deregulated with microvascular invasion or growth advantage. In the HCC samples with higher Gα<SUB>12</SUB> level, a correlation existed in the comparison of relative changes of Gα<SUB>12</SUB> and ZEB1. In conclusion, Gα<SUB>12</SUB> overexpressed in HCC causes ZEB1 induction by deregulating p53-responsive miRNAs, which may facilitate epithelial–mesenchymal transition and growth of liver tumor. These findings highlight the significance of Gα<SUB>12</SUB> upregulation in liver tumor progression, implicating Gα<SUB>12</SUB> as an attractive therapeutic target.

      • KCI등재

        Indirect Method for Quantification of Cellular Biomass in a Solidscontaining Medium Used as Pre-culture for Cellulase Production

        F. M. Cunha,A. L. G. Bacchin,A. C. L. Horta,T. C. Zangirolami,A. C. Badino,C. S. Farinas 한국생물공학회 2012 Biotechnology and Bioprocess Engineering Vol.17 No.1

        A process that combines the advantages of solid state fermentation (SSF) and submerged fermentation (SmF) could increase the efficiency of cellulase production required in the cellulosic ethanol industry. Due to the difficulty of measuring cellular biomass in the presence of solids, we developed a novel methodology for indirect quantification of biomass during production of the preculture for a combined fermentation process. Cultivation of Aspergillus niger was initiated as SSF using sugar cane bagasse as a solid substrate. Experiments were conducted in the absence of bagasse to determine growth kinetic parameters. Changes in glucose and biomass concentrations were measured. and the data were used for simulation employing a simple unstructured model. Parameters were estimated by applying a combination of Simulated Annealing (SA) and Levenberg-Marquardt (LM) algorithms to search for minimization of the error between model estimates and experimental data. Growth kinetics followed the Contois model, with a maximum specific growth rate (μmax) of 0.042/h, a yield coefficient for biomass formation (Yx/s) of 0.30 g/g and a death constant (kD) of 0.005/h.These parameters were used to simulate cellular growth in the solids-containing medium. The proposed model accurately described the experimental data and succeeded in simulating the cell concentration profile. The selected pre-culture conditions (24 h as SSF followed by 48 h as SmF) were applied for cellulase production using the combined fermentation process and resulted in an endoglucanase activity (1,052 ± 34 U/L) greater than that obtained using the conventional SmF procedure (824 ± 44 U/L). Besides the standardization of pre-culture conditions, this methodology could be very useful in systems where direct measurement of cell mass is not possible.

      • KCI등재

        CFD OPTIMIZATION OF A 2-STROKE RANGE EXTENDER ENGINE

        E. MATTARELLI,C. A. RINALDINI,G. CANTORE 한국자동차공학회 2015 International journal of automotive technology Vol.16 No.3

        A very promising concept for small range extenders (peak power less than 40 kW) is represented by the 2- stroke, direct injection spark ignition engine, with scavenging and exhaust ports controlled by the piston, and an external pump. The most important issue to be addressed on this type of engines is the compliance with stringent rules on pollutant emissions, which depends on combustion patterns and the quality of the scavenging process. The latter is generally hindered by the symmetry of ports timings, but this handicap can be canceled by adopting a patented rotary valve, controlling the flow through a set of auxiliary transfer ports, and using a piston pump for delivering air to the power cylinder and enhancing the balance of the crankshaft. The paper reviews the design of a virtual engine, rated at 35 kW at 5600 rpm, and developed according to the above mentioned concepts. Design has been driven by CFD simulation, using, whenever possible, experimentally calibrated numerical models, or experimental information derived from similar projects. Particular care has been devoted to characterize the scavenging process and the flow patterns within the cylinder and through the ports, analyzing the influence of the rotary induction valve. Engine performance parameters have been predicted by using a well-established commercial software (GT-Power, by Gamma Technologies), while CFD-3D analyses have been carried out by means of a customized version of the KIVA-3V code. The whole study is conceived as the basis for the construction of a physical prototype. The power target has been virtually achieved with a very light and compact engine (estimated weight without the close-coupled electric motor: 35 kg). A three-way catalyst allows the engine to comply with the most stringent emission regulations, without relevant penalizations on fuel efficiency. Furthermore, the engine can work with lean mixtures, achieving a minimum specific fuel consumption comparable to a current automotive Diesel engine (223 g/kWh). This excellent result is due to the low friction and pumping losses of the 2-Stroke engine, as well as to the compactness of the combustion chamber and the capability to stratify the charge.

      • SCISCIESCOPUS

        Direct electrochemistry of cytochrome c with three-dimensional nanoarchitectured multicomponent composite electrode and nitrite biosensing

        Shanmugasundaram, K.,Sai-Anand, G.,Gopalan, A.I.,Lee, H.G.,Yeo, H.K.,Kang, S.W.,Lee, K.P. Elsevier Sequoia 2016 Sensors and actuators. B Chemical Vol.228 No.-

        A novel electrochemical nitrite ion (NO<SUB>2</SUB><SUP>-</SUP>) biosensor was designed and fabricated by modifying a glassy carbon electrode (GCE) into three-dimensional nanoarchitectured electrode (3DNE) using a multicomponent nanocomposite (MCNC) film composed of graphene embedded titanium dioxide nanowires (TiO<SUB>2</SUB>(G) NWs), thiol-functionalized polyaniline (PANI(SH)), gold nanoparticles (Au), and immobilized cytochrome c (cyt c). The new NO<SUB>2</SUB><SUP>-</SUP> biosensor was designated as cyt c/TiO<SUB>2</SUB>(G) NWsΠANI(SH)-Au MCNC/3DNE. The assembly of the 3DNE, involved sequential depositions of PANI(SH) and Au over previously synthesized TiO<SUB>2</SUB>(G) NWs by electrospinning-hydrothermal processes and immobilization of the cyt c onto the TiO<SUB>2</SUB>(G) NWs/PANI(SH)/Au MCNC film. The cyt c/TiO<SUB>2</SUB>(G) NWsΠANI(SH)-Au MCNC/3DNE exhibited direct electron transfer from cyt c to the electrode at a high rate constant (25.34s<SUP>-1</SUP>). The fabricated cyt c/TiO<SUB>2</SUB>(G) NWsΠANI(SH)-Au MCNC/3DNE showed high selectivity to NO<SUB>2</SUB><SUP>-</SUP> ions with excellent sensitivity (9.2μA/mM), a wide linear concentration range (10μM-720mM), and a low detection limit (0.05μM). Additionally, the cyt c/TiO<SUB>2</SUB>(G) NWsΠANI(SH)-Au MCNC/3DNE exhibited high stability with good reproducibility and repeatability.

      • A study of nerve agent model organophosphonate binding with manganese-A<sub>2</sub>B-corrole and -A<sub>2</sub>B<sub>2</sub>-porphyrin systems

        Kim, K.,Kim, I.,Maiti, N.,Kwon, S.J.,Bucella, D.,Egorova, O.A.,Lee, Y.S.,Kwak, J.,Churchill, D.G. Pergamon Press 2009 Polyhedron Vol.28 No.12

        Herein the synthesis and binding studies of novel trans-A<SUB>2</SUB>B-corrole and trans-A<SUB>2</SUB>B<SUB>2</SUB>-porphyrin derivatives are presented in comparing manganese(III)-organophosphonate (OP) binding (e.g., M<SUP>n+</SUP>←O?PR(OR)<SUB>2</SUB>) capabilities. H<SUB>3</SUB>(PFP-VC) [PFP-VC=5,15-di(pentafluorophenyl)-10-(3-vinylphenyl)corrolate] was synthesized by way of literature procedures and was characterized by a variety of 2-D NMR spectroscopic techniques and single-crystal X-ray diffraction. These compounds represent the first example of 3-vinyl-phenyl-containing meso-substituted corroles or porphyrins. Mn(PFP-VC) (3) was treated separately with (CH<SUB>3</SUB>CH<SUB>2</SUB>O)<SUB>2</SUB>P?O(C<SUB>3</SUB>H<SUB>6</SUB>NMe<SUB>2</SUB>), (C<SUB>4</SUB>H<SUB>9</SUB>O)<SUB>2</SUB>P?O(Me), (C<SUB>2</SUB>H<SUB>5</SUB>O)<SUB>2</SUB>P?O(CH<SUB>2</SUB>COCH<SUB>3</SUB>), (CH<SUB>3</SUB>CH<SUB>2</SUB>O)<SUB>2</SUB>P?O(Me), to give 1:1 adducts, as determined by UV-Vis spectroscopy (Job Plot), giving a red shift; Ph<SUB>3</SUB>P?O, was also found to bind, but very weakly. The trans-A<SUB>2</SUB>B<SUB>2</SUB>-porphyrin analogue Mn(PFP-VP) (4) was also prepared by way of a literature procedure; related binding studies gave 1:1 organophosphonate-Mn(PFP-VP) adducts (Job Plot). A clean blue shift occurred for the Mn-porphyrins at higher organophosphonate loadings (K<SUB>a</SUB> values: 6.7 (0.9)-11.9 (0.4)M<SUP>-1</SUP>). DFT geometry optimizations of O?P(OMe)<SUB>2</SUB>Me binding and formal Mn-O or P-O cleavage products in the unsubstituted neutral Mn-corrolato and -porphyrinato systems with a range of metal-based spin states revealed greatest stability in formal phosphoryl oxygen binding (energies: 11-13kcal/mol) for the Mn-corrole (singlet); the Mn-porphyrin (sextet) was also quite stable.

      • Characteristics of a-GaN films and a-AlGaN/GaN heterojunctions prepared on r-sapphire by two-stage growth process

        Polyakov, A. Y.,Jang, Lee-Woon,Smirnov, N. B.,Govorkov, A. V.,Kozhukhova, E. A.,Yugova, T. G.,Reznik, V. Y.,Pearton, S. J.,Baik, Kwang Hyeon,Hwang, Sung-Min,Jung, Sukkoo,Lee, In-Hwan American Institute of Physics 2011 JOURNAL OF APPLIED PHYSICS - Vol.110 No.9

        <P>The electrical properties, presence of deep electron and hole traps and photoluminescence spectra were measured for undoped a-GaN films grown by metal-organic chemical vapor deposition (MOCVD) in a two-stage process using a high V/III ratio at the first stage and low V/III ratio at the second stage. Growth was performed on r-sapphire substrates with a high temperature GaN nucleation layer. The films showed a full width at half maximum of 450-470 arcseconds for the (11-20) x-ray rocking curve with little anisotropy with respect to the sample rotation around the growth direction. The stacking fault (SF) density determined by selective etching was similar to 5 x 10(4) cm(-1). The residual donor concentration was 10(14)-10(15) cm(-3), with a very low density (2.5 x 10(13) cm(-3)) of electron traps located at E-c - 0.6 eV, which are believed to be one of the major non-radiative recombination centers in nonpolar GaN. Consequently, the films showed a high intensity of bandedge luminescence with negligible contribution from defect bands associated with SFs. In contrast to previously studied nonpolar GaN films, the a-GaN layers showed a high concentration of gallium-vacancy-related acceptors near E-v + 1 eV and a strong yellow luminescence band, both indicating that growth conditions were effectively N-rich. a-AlGaN/GaN heterojunctions with thin heavily Si doped AlGaN barriers made on a-GaN substrates showed two-dimensional electron gas (2DEG) concentrations of 1.2 x 10(13) cm(-3), with 2DEG mobility of 80 cm(2)/Vs. Capacitance-voltage profiling of Schottky diodes on these HJs suggest that the 2DEG is fully depleted by the built-in voltage of the Schottky diode. (C)2011 American Institute of Physics. [doi: 10.1063/1.3658026]</P>

      • KCI등재

        Gröbner-Shirshov bases and embedding of a semigroup in a group

        E. G. Karpuz,A. S. Cevik,F. Ates,J. Koppitz 장전수학회 2015 Advanced Studies in Contemporary Mathematics Vol.25 No.4

        The main goal of this paper is to show that if a group G has a Gröbner-Shirshov basis that satisfies the condition R+, then the semigroup P having positive rules in < as a dening relation embeds in this group G. As a corollary of our result, we obtain that the semigroup B+ n+1 of braids can be embedded in the braid group. The main goal of this paper is to show that if a group G has a Grobner-Shirshov basis that satisfies the condition R+, then the semigroup P having positive rules in < as a dening relation embeds in this group G. As a corollary of our result, we obtain that the semigroup B+ n+1 of braids can be embedded in the braid group.

      • SCIESCOPUSKCI등재

        Tethering Meat Goats Grazing Forage of High Nutritive Value and Low to Moderate Mass

        Patra, A.K.,Puchala, R.,Detweiler, G.,Dawson, L.J.,Animut, G.,Sahlu, T.,Goetsch, A.L. Asian Australasian Association of Animal Productio 2008 Animal Bioscience Vol.21 No.9

        Twenty-four yearling Boer$\times$Spanish goats were used in a crossover design experiment to determine effects of tethering on forage selection, intake and digestibility, grazing behavior and energy expenditure (EE) with forage high in nutritive value and low to moderate in mass. Objectives were to determine if tethered goats could be used as a model for study of unrestrained animals and to characterize tethering as a production practice. Four 0.72-ha pastures of wheat (Triticum aestivum) and berseem clover (Trifolium alexandrium) were grazed in December and January. Each pasture hosted six animals, three with free movement and three attached to a 4.11-m tether for access to a circular area of $53.1m^2$. Tethering areas were moved each day. One animal of each treatment and pasture was used to determine forage selection, fecal output or grazing behavior and EE; therefore, there were eight observations per treatment. Mass of forage DM before grazing in Tethered areas averaged 1,280 and 1,130 kg/ha in periods 1 and 2, respectively. The CP concentration in ingesta was greater ((p<0.05) 239 and 209 g/kg; SE = 8.0) and the NDF level was lower (p<0.05) for Free vs. Tethered animals (503 and 538 g/kg; SE = 12.0); in vitro true DM digestion was similar between treatments (0.808 and 0.807 for Free and Tethered, respectively; SE = 0.0096). Intakes of DM (1,013 and 968 g/d; SE = 78.6), NDF (511 and 521 g/d; SE = 39.9) and ME (10.9 and 10.7 MJ/d; SE = 0.90) were similar between treatments, but CP intake was greater (p<0.05) for Free vs. Tethered animals (241 and 203 g/d; SE = 17.2). There were small treatment differences in in vivo apparent digestibility of OM ((p<0.05) 0.780 and 0.814; SE = 0.0049), CP ((p<0.05) 0.800 and 0.817; SE = 0.0067) and NDF ((p<0.09) 0.777 and 0.760 for Free and Tethered, respectively; SE = 0.0078). There were no treatment effects on time spent ruminating or grazing (346 and 347 min/d for Free and Tethered, respectively; SE = 42.5), but EE was considerably greater (p<0.05) for Free vs. Tethered animals (571 and 489 kJ/kg $BW^{0.75}$; SE = 8.9). In conclusion, with forage of high nutritive value and low to moderate in mass, tethering can offer a production advantage over free grazing of less energy used for activity despite similar grazing time. With forage removal considerably less than that available for grazing, effects of tethering on chemical composition of selected forage were small and less than needed to markedly affect digestion. Tethering may offer a means of studying some aspects of grazing by ruminants, but would not seem suitable for energy metabolism.

      • Combined Genotype Analyses of Precursor miRNA-196a2 and -499a Variants with Hepatic and Renal Cancer Susceptibility- a Preliminary Study

        Toraih, Eman A,Fawzy, Manal S,Elgazzaz, Mona G,Hussein, Mohammad H,Shehata, Rasha H,Daoud, Hisham G Asian Pacific Journal of Cancer Prevention 2016 Asian Pacific journal of cancer prevention Vol.17 No.7

        MicroRNAs, a novel class of small non-coding RNAs, are key players in many cellular processes, including cell proliferation, differentiation, invasion and regeneration. Tissue and circulatory microRNAs could serve as useful clinical biomarkers and deregulated expression levels have been observed in various cancers. Gene variants may alter microRNA processing and maturation. Thus, we aimed to investigate the association of MIR-196a2 rs11614913 (C/T), MIR-499a rs3746444 (A/G) polymorphisms and their combination with cancer susceptibility in an Egyptian population. Sixty five renal cell carcinoma (RCC) and 60 hepatocellular carcinoma (HCC) patients and 150 controls were enrolled in the study. They were genotyped using real-time polymerase chain reaction technology. Both $miR-196a2^*T$ and $miR-499a*G$ were associated with RCC risk, but only $miR-196a^*T$ was associated with HCC development. Carriage of the homozygote combinations ($MIR196a2^*TT+MIR499a^*AA$) and ($MIR196a2^*CC+MIR499a^*GG$) was associated with 25 and 48 fold elevation of likelhood to develop RCC, respectively. The miR-196a2 SNP was also linked with larger tumor size in RCC and advanced tumor stage in HCC. miR-196a2 and miR-499a combined genotypes were associated with RCC and HCC. Further functional analysis of SNPs is required to confirm relationships between genotypes and phenotypes.

      • SCIESCOPUSKCI등재

        Restriction of Metabolizable Energy in Broiler Growers and Its Impact on Grower and Breeder Performance

        Sunder, G. Skyam,Kumar, Ch. Vijaya,Panda, A.K.,Raju, M.V.L.N.,Rao, S.V. Rama,Gopinath, N.C.S.,Reddy, M.R. Asian Australasian Association of Animal Productio 2007 Animal Bioscience Vol.20 No.8

        Metabolizable energy (ME) required for basal metabolism, activity and growth was considered as the criterion for targeting specific increases in body weight (100 g/week) of broiler chicks during the grower phase (5-20 weeks) and its impact was evaluated on breeder performance. Broiler female chicks (460) from a synthetic dam line were randomly distributed to 4 test groups with 23 replicates of 5 birds each and housed in cages. The first group (ME-100) was offered a calculated amount of ME by providing a measured quantity of grower diet (160 g protein and 2,600 kcal ME/kg) which increased with age and weight gain (133-294 kcal/bird/day). The other three groups were offered 10 or 20% less ME (ME-90 and ME-80, respectively) and 10% excess ME (ME-110) over the control group (ME-100). From 21 weeks of age, a single breeder diet (170 g protein and 2,600 kcal ME/kg) was uniformly fed to all groups and the impact of grower ME restriction on breeder performance evaluated up to 58 weeks. The targeted body weight gain of 1,600 g in a 16-week period was achieved by pullets of the ME-100 group almost one week earlier by gaining 8.7 g more weight per week. However, pullets in the ME-90 group gained 1,571 g during the same period, which was closer to the targeted weight. At 20 weeks of age, the conversion efficiency of feed (5.21-5.37), ME (13.9-14.1 kcal/g weight gain) and protein (0.847-0.871 g/g weight gain), eviscerated meat yield, giblet and tibia weights were not influenced by ME restriction, but the weights of abdominal fat and liver were higher with increased ME intake. Reduction of ME by 10% in the grower period significantly delayed sexual maturity (169.3 d), but increased egg production (152.5 /bird) with better persistency. Improved conversion efficiency of feed, ME and protein per g egg content were also observed in this group up to 56 weeks. The fertility and hatchability at 58 weeks of age were higher in the ME-90 group compared to the control and 10% excess ME feeding. In conclusion, the present study revealed the possibility of achieving targeted weight gain in broiler growers by feeding measured quantities of ME during the rearing period with consequential benefits in breeder performance.

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