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Review: Animal model and the current understanding of molecule dynamics of adipogenesis
- C. F. Campos, M. S. Duarte, S. E. F. Guimarães, L. L. Verardo, S. Wei, M. Du, Z. Jiang, W. G. Bergen, G. J. Hausman, M. Fernyhough-Culver, E. Albrecht, M. V. Dodson
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Among several potential animal models that can be used for adipogenic studies, Wagyu cattle is the one that presents unique molecular mechanisms underlying the deposit of substantial amounts of intramuscular fat. As such, this review is focused on current knowledge of such mechanisms related to adipose tissue deposition using Wagyu cattle as model. So abundant is the lipid accumulation in the skeletal muscles of these animals that in many cases, the muscle cross-sectional area appears more white (adipose tissue) than red (muscle fibers). This enhanced marbling accumulation is morphologically similar to that seen in numerous skeletal muscle dysfunctions, disease states and myopathies; this might indicate cross-similar mechanisms between such dysfunctions and fat deposition in Wagyu breed. Animal models can be used not only for a better understanding of fat deposition in livestock, but also as models to an increased comprehension on molecular mechanisms behind human conditions. This revision underlies some of the complex molecular processes of fat deposition in animals.
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- By Rose Teteki Abbey, K. C. Abraham, David Tuesday Adamo, LeRoy H. Aden, Efrain Agosto, Victor Aguilan, Gillian T. W. Ahlgren, Charanjit Kaur AjitSingh, Dorothy B E A Akoto, Giuseppe Alberigo, Daniel E. Albrecht, Ruth Albrecht, Daniel O. Aleshire, Urs Altermatt, Anand Amaladass, Michael Amaladoss, James N. Amanze, Lesley G. Anderson, Thomas C. Anderson, Victor Anderson, Hope S. Antone, María Pilar Aquino, Paula Arai, Victorio Araya Guillén, S. Wesley Ariarajah, Ellen T. Armour, Brett Gregory Armstrong, Atsuhiro Asano, Naim Stifan Ateek, Mahmoud Ayoub, John Alembillah Azumah, Mercedes L. García Bachmann, Irena Backus, J. Wayne Baker, Mieke Bal, Lewis V. Baldwin, William Barbieri, António Barbosa da Silva, David Basinger, Bolaji Olukemi Bateye, Oswald Bayer, Daniel H. Bays, Rosalie Beck, Nancy Elizabeth Bedford, Guy-Thomas Bedouelle, Chorbishop Seely Beggiani, Wolfgang Behringer, Christopher M. Bellitto, Byard Bennett, Harold V. Bennett, Teresa Berger, Miguel A. Bernad, Henley Bernard, Alan E. Bernstein, Jon L. Berquist, Johannes Beutler, Ana María Bidegain, Matthew P. Binkewicz, Jennifer Bird, Joseph Blenkinsopp, Dmytro Bondarenko, Paulo Bonfatti, Riet en Pim Bons-Storm, Jessica A. Boon, Marcus J. Borg, Mark Bosco, Peter C. Bouteneff, François Bovon, William D. Bowman, Paul S. Boyer, David Brakke, Richard E. Brantley, Marcus Braybrooke, Ian Breward, Ênio José da Costa Brito, Jewel Spears Brooker, Johannes Brosseder, Nicholas Canfield Read Brown, Robert F. Brown, Pamela K. Brubaker, Walter Brueggemann, Bishop Colin O. Buchanan, Stanley M. Burgess, Amy Nelson Burnett, J. Patout Burns, David B. Burrell, David Buttrick, James P. Byrd, Lavinia Byrne, Gerado Caetano, Marcos Caldas, Alkiviadis Calivas, William J. Callahan, Salvatore Calomino, Euan K. Cameron, William S. Campbell, Marcelo Ayres Camurça, Daniel F. Caner, Paul E. Capetz, Carlos F. Cardoza-Orlandi, Patrick W. Carey, Barbara Carvill, Hal Cauthron, Subhadra Mitra Channa, Mark D. Chapman, James H. Charlesworth, Kenneth R. Chase, Chen Zemin, Luciano Chianeque, Philip Chia Phin Yin, Francisca H. Chimhanda, Daniel Chiquete, John T. Chirban, Soobin Choi, Robert Choquette, Mita Choudhury, Gerald Christianson, John Chryssavgis, Sejong Chun, Esther Chung-Kim, Charles M. A. Clark, Elizabeth A. Clark, Sathianathan Clarke, Fred Cloud, John B. Cobb, W. Owen Cole, John A Coleman, John J. Collins, Sylvia Collins-Mayo, Paul K. Conkin, Beth A. Conklin, Sean Connolly, Demetrios J. Constantelos, Michael A. Conway, Paula M. Cooey, Austin Cooper, Michael L. Cooper-White, Pamela Cooper-White, L. William Countryman, Sérgio Coutinho, Pamela Couture, Shannon Craigo-Snell, James L. Crenshaw, David Crowner, Humberto Horacio Cucchetti, Lawrence S. Cunningham, Elizabeth Mason Currier, Emmanuel Cutrone, Mary L. Daniel, David D. Daniels, Robert Darden, Rolf Darge, Isaiah Dau, Jeffry C. Davis, Jane Dawson, Valentin Dedji, John W. de Gruchy, Paul DeHart, Wendy J. Deichmann Edwards, Miguel A. De La Torre, George E. Demacopoulos, Thomas de Mayo, Leah DeVun, Beatriz de Vasconcellos Dias, Dennis C. Dickerson, John M. Dillon, Luis Miguel Donatello, Igor Dorfmann-Lazarev, Susanna Drake, Jonathan A. Draper, N. Dreher Martin, Otto Dreydoppel, Angelyn Dries, A. J. Droge, Francis X. D'Sa, Marilyn Dunn, Nicole Wilkinson Duran, Rifaat Ebied, Mark J. Edwards, William H. Edwards, Leonard H. Ehrlich, Nancy L. Eiesland, Martin Elbel, J. Harold Ellens, Stephen Ellingson, Marvin M. Ellison, Robert Ellsberg, Jean Bethke Elshtain, Eldon Jay Epp, Peter C. Erb, Tassilo Erhardt, Maria Erling, Noel Leo Erskine, Gillian R. Evans, Virginia Fabella, Michael A. Fahey, Edward Farley, Margaret A. Farley, Wendy Farley, Robert Fastiggi, Seena Fazel, Duncan S. Ferguson, Helwar Figueroa, Paul Corby Finney, Kyriaki Karidoyanes FitzGerald, Thomas E. FitzGerald, John R. Fitzmier, Marie Therese Flanagan, Sabina Flanagan, Claude Flipo, Ronald B. Flowers, Carole Fontaine, David Ford, Mary Ford, Stephanie A. Ford, Jim Forest, William Franke, Robert M. Franklin, Ruth Franzén, Edward H. Friedman, Samuel Frouisou, Lorelei F. Fuchs, Jojo M. Fung, Inger Furseth, Richard R. Gaillardetz, Brandon Gallaher, China Galland, Mark Galli, Ismael García, Tharscisse Gatwa, Jean-Marie Gaudeul, Luis María Gavilanes del Castillo, Pavel L. Gavrilyuk, Volney P. Gay, Metropolitan Athanasios Geevargis, Kondothra M. George, Mary Gerhart, Simon Gikandi, Maurice Gilbert, Michael J. Gillgannon, Verónica Giménez Beliveau, Terryl Givens, Beth Glazier-McDonald, Philip Gleason, Menghun Goh, Brian Golding, Bishop Hilario M. Gomez, Michelle A. Gonzalez, Donald K. Gorrell, Roy Gottfried, Tamara Grdzelidze, Joel B. Green, Niels Henrik Gregersen, Cristina Grenholm, Herbert Griffiths, Eric W. Gritsch, Erich S. Gruen, Christoffer H. Grundmann, Paul H. Gundani, Jon P. Gunnemann, Petre Guran, Vidar L. Haanes, Jeremiah M. 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Phan, Isabel Apawo Phiri, William S. F. Pickering, Derrick G. Pitard, William Elvis Plata, Zlatko Plese, John Plummer, James Newton Poling, Ronald Popivchak, Andrew Porter, Ute Possekel, James M. Powell, Enos Das Pradhan, Devadasan Premnath, Jaime Adrían Prieto Valladares, Anne Primavesi, Randall Prior, María Alicia Puente Lutteroth, Eduardo Guzmão Quadros, Albert Rabil, Laurent William Ramambason, Apolonio M. Ranche, Vololona Randriamanantena Andriamitandrina, Lawrence R. Rast, Paul L. Redditt, Adele Reinhartz, Rolf Rendtorff, Pål Repstad, James N. Rhodes, John K. Riches, Joerg Rieger, Sharon H. Ringe, Sandra Rios, Tyler Roberts, David M. Robinson, James M. Robinson, Joanne Maguire Robinson, Richard A. H. Robinson, Roy R. Robson, Jack B. Rogers, Maria Roginska, Sidney Rooy, Rev. Garnett Roper, Maria José Fontelas Rosado-Nunes, Andrew C. Ross, Stefan Rossbach, François Rossier, John D. Roth, John K. Roth, Phillip Rothwell, Richard E. 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Yee, Viktor Yelensky, Yeo Khiok-Khng, Gustav K. K. Yeung, Angela Yiu, Amos Yong, Yong Ting Jin, You Bin, Youhanna Nessim Youssef, Eliana Yunes, Robert Michael Zaller, Valarie H. Ziegler, Barbara Brown Zikmund, Joyce Ann Zimmerman, Aurora Zlotnik, Zhuo Xinping
- Edited by Daniel Patte, Vanderbilt University, Tennessee
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- The Cambridge Dictionary of Christianity
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- 05 August 2012
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- 20 September 2010, pp xi-xliv
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The relationship between ADHD and key cognitive phenotypes is not mediated by shared familial effects with IQ
- A. C. Wood, F. Rijsdijk, K. A. Johnson, P. Andreou, B. Albrecht, A. Arias-Vasquez, J. K. Buitelaar, G. McLoughlin, N. N. J. Rommelse, J. A. Sergeant, E. J. S. Sonuga-Barke, H. Uebel, J. J. van der Meere, T. Banaschewski, M. Gill, I. Manor, A. Miranda, F. Mulas, R. D. Oades, H. Roeyers, A. Rothenberger, H. C. Steinhausen, S. V. Faraone, P. Asherson, J. Kuntsi
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- Psychological Medicine / Volume 41 / Issue 4 / April 2011
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- 04 June 2010, pp. 861-871
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Background
Twin and sibling studies have identified specific cognitive phenotypes that may mediate the association between genes and the clinical symptoms of attention deficit hyperactivity disorder (ADHD). ADHD is also associated with lower IQ scores. We aimed to investigate whether the familial association between measures of cognitive performance and the clinical diagnosis of ADHD is mediated through shared familial influences with IQ.
MethodMultivariate familial models were run on data from 1265 individuals aged 6–18 years, comprising 920 participants from ADHD sibling pairs and 345 control participants. Cognitive assessments included a four-choice reaction time (RT) task, a go/no-go task, a choice–delay task and an IQ assessment. The analyses focused on the cognitive variables of mean RT (MRT), RT variability (RTV), commission errors (CE), omission errors (OE) and choice impulsivity (CI).
ResultsSignificant familial association (rF) was confirmed between cognitive performance and both ADHD (rF=0.41–0.71) and IQ (rF=−0.25 to −0.49). The association between ADHD and cognitive performance was largely independent (80–87%) of any contribution from etiological factors shared with IQ. The exception was for CI, where 49% of the overlap could be accounted for by the familial variance underlying IQ.
ConclusionsThe aetiological factors underlying lower IQ in ADHD seem to be distinct from those between ADHD and RT/error measures. This suggests that lower IQ does not account for the key cognitive impairments observed in ADHD. The results have implications for molecular genetic studies designed to identify genes involved in ADHD.
Theoretical study of turbulent channel flow: bulk properties, pressure fluctuations, and propagation of electromagnetic waves
- V. M. Canuto, G. J. Hartke, A. Battaglia, J. Chasnov, G. F. Albrecht
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- Journal of Fluid Mechanics / Volume 211 / February 1990
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- 26 April 2006, pp. 1-35
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In this paper, we apply two theoretical turbulence models, DIA and the recent GISS model, to study properties of a turbulent channel flow. Both models provide a turbulent kinetic energy spectral function E(k) as the solution of a nonlinear equation; the two models employ the same source function but different closures. The source function is characterized by a rate ns(k) which is derived from the complex eigenvalues of the Orr–Sommerfeld equation in which the basic flow is taken to be of a Poiseuille type. The Orr–Sommerfeld equation is solved for a variety of Reynolds numbers corresponding to available experimental data. A physical argument is presented whereby the central line velocity characterizing the basic flow, U0L, is not to be identified with the U0 appearing in the experimental Reynolds number. A renormalization is suggested which has the effect of yielding growth rates of magnitude comparable with those calculated by Orszag & Patera based on their study of a secondary instability. From the practical point of view, this renormalization frees us from having to solve the rather time-consuming equations describing the secondary instability. This point is discussed further in §13. In the present treatment, the shear plays only the role of a source of energy to feed the turbulence and not the possible additional role of an interaction between the shear of the mean flow and the eddy vorticity that would give rise to resonance effects when the shear is equal to or larger than the eddy vorticities. The inclusion of this possible resonance phenomenon, which is not expected to affect the large-eddy behaviour and thus the bulk properties, is left for a future study. The theoretical results are compared with two types of experimental data: (a) turbulence bulk properties, table 4, and (b) properties that depend strongly on the structure of the turbulence spectrum at low wavenumbers (i.e. large eddies), tables 5 and 6. The latter data are taken from recent experiments measuring the changes in the propagation of an electromagnetic wave through a turbulent channel flow. The fluctuations in the refractive index of the turbulent medium are thought to be due to pressure fluctuations whose spectral function Π(k) is contributed mostly by the interaction between the mean flow and the turbulent velocity. The spectrum Π(k) must be computed as a function of the wavenumber k, the position in the channel x2, and the width of the channel Δ. The only existing analytical expression for Π(k), due to Kraichnan, cannot be used in the present case because it applies to the case x2 = 0 and Δ = ∞, which corresponds to the case of a flat plate, not a finite channel. A general expression for Π(k, x2; Δ) is derived here for the first time and employed to calculate the fraction of incoherent radiation scattered out of a coherent beam. In §11, we treat anisotropy and show how to extend the previous results to include an arbitrary degree of anisotropy α in the sizes of the eddies. We show that the theoretical one-dimensional spectra yield a better fit to the data for a degree of anisotropy (α ≈ 4) that is within the range of experimental values. We also extend the expression for Π(k, x2; Δ) to Π(k, x2; Δ, α) and compute the pressure fluctuations for different values of α. Similarly, we evaluate the fraction of electromagnetic energy scattered by an anisotropic turbulent flow and find a good fit to the laboratory data for a value of α ≈ 4–6. Scaling formulae for the scattered fraction are presented in §12. These formulae reproduce the calculated results, both with and without the addition of anisotropy, to better than 5%.
Theoretical problems however remain which will require further study: among them, lack of backscatter (i.e. the transfer of energy from large to small wavenumbers) in the GISS model, possible resonance effects between the shear and eddy vorticity, behaviour of the one-dimensional spectral function at low wavenumbers, and the role of the secondary instability. These topics are now under investigation.
Luminescence Related to Stacking Faults in Heterepitaxially Grown Wurtzite GaN
- M. Albrecht, S. Christiansen, G. Salviati, C. Zanotti-Fregonara, Y. T. Rebane, Y. G. Shreter, M. Mayer, A. Pelzmann, M. Kamp, K. J. Ebeling, M. D. Bremser, R. F. Davis, H. P. Strunk
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- MRS Online Proceedings Library Archive / Volume 468 / 1997
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- 10 February 2011, 293
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- 1997
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We correlate structure analyzed by transmission electron microscopy with photo- and cathodoluminescence studies of GaN/Al2O3(0001) and GaN/SiC(0001) and show that an additional UV line at 364nm/3.4eV can be connected to the occurrence of stacking faults. We explain the occurrence of this line by a model that is based on the concept of excitons bound to stacking faults that form a quantum well of cubic material in the wurtzite lattice of the layer material. The model is in reasonable agreement with the experimental observations.