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Full-Text Articles in Life Sciences

Organochlorine Levels In Seawater And Sediment From The Florida Gulf Coast, If Present, Are Low. , Richard B. Philp Nov 2006

Organochlorine Levels In Seawater And Sediment From The Florida Gulf Coast, If Present, Are Low. , Richard B. Philp

Richard B. Philp

Seawater and sediment from the Florida panhandle coast were assayed for a panel of 28 organochlorine insecticides and PCBs. No samples exeeded the detection limits of the analytical technique, which were well below levels reported for other ocean locales. Organochlorine levels in this area of the Gulf must be very low. This does not preclude their biomagnificatioon up the food web.


Physical And Structural Basis For The Strong Interactions Of The -Impy- Central Pairing Motif In The Polyamide F-Impyim, K. Buchmueller, S. Bailey, D. Matthews, Z. Taherbhai, J. Register, Z. Davis, Chrystal Bruce, C. O'Hare, J. Hartley, M. Lee Nov 2006

Physical And Structural Basis For The Strong Interactions Of The -Impy- Central Pairing Motif In The Polyamide F-Impyim, K. Buchmueller, S. Bailey, D. Matthews, Z. Taherbhai, J. Register, Z. Davis, Chrystal Bruce, C. O'Hare, J. Hartley, M. Lee

Chrystal D. Bruce

The polyamide f-ImPyIm has a higher affinity for its cognate DNA than either the parent analogue, distamycin A (10-fold), or the structural isomer, f-PyImIm (250-fold), has for its respective cognate DNA sequence. These findings have led to the formulation of a two-letter polyamide “language” in which the -ImPy- central pairings associate more strongly with Watson−Crick DNA than -PyPy-, -PyIm-, and -ImIm-. Herein, we further characterize f-ImPyIm and f-PyImIm, and we report thermodynamic and structural differences between -ImPy- (f-ImPyIm) and -PyIm- (f-PyImIm) central pairings. DNase I footprinting studies confirmed that f-ImPyIm is a stronger binder than distamycin A and f-PyImIm and …


Activation In Neural Networks Controlling Ingestive Behaviors: What Does It Mean, And How Do We Map And Measure It?, Alan G. Watts, Arshad M. Khan, Graciela Sanchez-Watts, Dawna Salter, Christina M. Neuner Apr 2006

Activation In Neural Networks Controlling Ingestive Behaviors: What Does It Mean, And How Do We Map And Measure It?, Alan G. Watts, Arshad M. Khan, Graciela Sanchez-Watts, Dawna Salter, Christina M. Neuner

Arshad M. Khan, Ph.D.

No abstract provided.


Biochemical Characterization Of The Major Sorghum Grain Peroxidase, Mamoudou H. Dicko, Harry Gruppen, Riet Hilhorst, Alphons G. J. Voragen, Willen W. H. Van Berkel Apr 2006

Biochemical Characterization Of The Major Sorghum Grain Peroxidase, Mamoudou H. Dicko, Harry Gruppen, Riet Hilhorst, Alphons G. J. Voragen, Willen W. H. Van Berkel

Pr. Mamoudou H. DICKO, PhD

The major cationic peroxidase in sorghum grain (SPC4) , which is ubiquitously present in all sorghum varieties was purified to apparent homogeneity, and found to be a highly basic protein (pI #1;11). MS analysis showed that SPC4 consists of two glycoforms with molecular masses of 34227 and 35629 Da and it contains a type-b heme. Chemical deglycosylation allowed to estimate sugar contents of 3.0% and 6.7% (w ⁄ w) in glycoform I and II, respectively, and a mass of the apoprotein of 33 246 Da. High performance anion exchange chromatography allowed to determine the carbohydrate constituents of the polysaccharide chains. …


The Importance Of Maltose In Transitory Starch Breakdown, Yan Lu, Thomas Sharkey Feb 2006

The Importance Of Maltose In Transitory Starch Breakdown, Yan Lu, Thomas Sharkey

Yan Lu

No abstract provided.


Pka-Mediated Erk1/2 Inactivation And Hsp70 Gene Expression Following Exercise, C.W. Melling, Matthew Krause, Earl Noble Dec 2005

Pka-Mediated Erk1/2 Inactivation And Hsp70 Gene Expression Following Exercise, C.W. Melling, Matthew Krause, Earl Noble

Jamie Melling

Exercise induces the expression of the cardioprotective protein, Hsp70, through the activation of its transcription factor HSF1. Recently, we reported that administration of a protein kinase A (PKA) inhibitor suppressed exercise-induced hsp70 gene expression, suggesting a role for PKA in the regulation of HSF1 activation in vivo. While the mechanism by which PKA regulates HSF1 is unclear, studies in vitro have reported that HSF1 is phosphorylated on two serine residues by mitogen activated protein kinases (MAPKs); ERK1/2 (ser307) and JNK/SAPK (ser363). As PKA is a regulator of these protein kinases, the current study examined the role of PKA in their …


Cellular And Organ Level Localization Of Maltose In Maltose-Excess Arabidopsis Mutants, Yan Lu, Jon Steichen, Sean Weise, Thomas Sharkey Dec 2005

Cellular And Organ Level Localization Of Maltose In Maltose-Excess Arabidopsis Mutants, Yan Lu, Jon Steichen, Sean Weise, Thomas Sharkey

Yan Lu

No abstract provided.


Imaging Islets Labeled Wth Magnetic Nanoparticules At 1.5 Tesla, J.H. Tai, Paula Foster, Alma Rosales, Biao Feng, Craig Ha, Violetta Martinez, Soha Ramadan, Jonatan Snir, C.W. Melling, Savita Dhanvantari, Brian Rutt, David White Dec 2005

Imaging Islets Labeled Wth Magnetic Nanoparticules At 1.5 Tesla, J.H. Tai, Paula Foster, Alma Rosales, Biao Feng, Craig Ha, Violetta Martinez, Soha Ramadan, Jonatan Snir, C.W. Melling, Savita Dhanvantari, Brian Rutt, David White

Jamie Melling

We have developed a magnetic resonance imaging (MRI) technique for imaging Feridex (superparamagnetic iron oxide [SPIO])-labeled islets of Langerhans using a standard clinical 1.5-Tesla (T) scanner and employing steady-state acquisition imaging sequence (3DFIESTA). Both porcine and rat islets were labeled with SPIO by a transfection technique using a combination of poly-l-lysine and electroporation. Electron microscopy demonstrated presence of SPIO particles within the individual islet cells, including beta-cells and particles trapped between cell membranes. Our labeling method produced a transfection rate of 860 pg to 3.4 ng iron per islet, dependent on the size of the islet. The labeling procedure did …


The Role Of Cytosolic A-Glucan Phosphorylase In Maltose Metabolism And The Comparison Of Amylomaltose In Arabidopsis And E. Coli, Yan Lu, Jon Steichen, Jian Yao, Thomas Sharkey Dec 2005

The Role Of Cytosolic A-Glucan Phosphorylase In Maltose Metabolism And The Comparison Of Amylomaltose In Arabidopsis And E. Coli, Yan Lu, Jon Steichen, Jian Yao, Thomas Sharkey

Yan Lu

No abstract provided.


The Effect Of Environmental Parameters And Cyanobacterial Blooms On Phytoplankton Dynamics Of A Portuguese Temperate Lake, Daniela De Figueiredo, Ana Reboleira, S. Antunes, N. Abrantes, U. Azeiteiro, F. Gonçalves, M. Pereira Dec 2005

The Effect Of Environmental Parameters And Cyanobacterial Blooms On Phytoplankton Dynamics Of A Portuguese Temperate Lake, Daniela De Figueiredo, Ana Reboleira, S. Antunes, N. Abrantes, U. Azeiteiro, F. Gonçalves, M. Pereira

Ana Sofia P.S. Reboleira

The increasing occurrence of cyanobacterial blooms in freshwaters is of great concern due to the ability of many cyanobacteria to produce cyanotoxins. In the present work, the eutrophied Vela Lake (Central Portugal), used for recreational purposes and as a water source for agriculture, was monitored every fortnight between 2000 and 2001. Phytoplankton diversity and densities were measured and correlated to environmental parameters. A seasonal phytoplanktonic succession was observed and it was mainly correlated with conductivity, temperature, total suspended solids and nutrients availability (particularly phosphorus). Diatoms were dominant during winter months (inferior temperatures and higher nutrients availability) followed by green algae …


Exchange Coupling And Contribution Of Induced Orbital Angular Momentum Of Low-Spin Fe^3+ Ions To Magnetic Anisotropy In Cyanide-Bridged Fe2m2 Molecular Magnets: Spin-Polarized Density-Functional Calculations, Stephen Holmes, Kyungwha Park Dec 2005

Exchange Coupling And Contribution Of Induced Orbital Angular Momentum Of Low-Spin Fe^3+ Ions To Magnetic Anisotropy In Cyanide-Bridged Fe2m2 Molecular Magnets: Spin-Polarized Density-Functional Calculations, Stephen Holmes, Kyungwha Park

Stephen Holmes

Electronic structure and intramolecular exchange constants are calculated for three cyanide-bridged molecular magnets, Tp#1;FeIII#1;CN3MII#1;DMF4#4;2#1;OTf2 ·2DMF #1;MII=Mn,Co,Ni #1;abbreviated as Fe2Mn2, Fe2Co2, and Fe2Ni2 that have been recently synthesized, within a generalized-gradient approximation in spin-polarized density-functional theory #1;DFT. Here Tp#1;=C3#1;CH32HN2#4;3BH, OTf =O3SCF3, and DMF=HCON#1;CH32. Due to strong ligand fields present in the Tp#1;FeIII#1;CN3#4; − units, the Fe3+ ions exhibit a low ground-state spin of S=1/2. Our calculations show that the metal ions in the Fe2Mn2 molecule interact antiferromagnetically via cyanide ligands, while those in the Fe2Co2 and Fe2Ni2 molecule interact ferromagnetically. The calculations also suggest that the smallest gaps between the highest …


Recent Advances In Chlorophyll Biosynthesis, David Bollivar Dec 2005

Recent Advances In Chlorophyll Biosynthesis, David Bollivar

David Bollivar

The importance of chlorophyll (Chl) to the process of photosynthesis is obvious, and there is clear evidence that the regulation of Chl biosynthesis has a significant role in the regulation of assembly of the photosynthetic apparatus. The understanding of Chl biosynthesis has rapidly advanced in recent years. The identification of genetic loci associated with each of the biochemical steps has been accompanied by a greater appreciation of the role of Chl biosynthesis intermediates in intracellular signaling. The purpose of this review is to provide a source of information for all the steps in Chl and bacteriochlorophyll a biosynthesis, with an …


Wcen: A Computer Program For Initial Processing Of Fiber Diffraction Patterns, Wen Bian, Hong Wang, Ian Mccullough, Gerald Stubbs Dec 2005

Wcen: A Computer Program For Initial Processing Of Fiber Diffraction Patterns, Wen Bian, Hong Wang, Ian Mccullough, Gerald Stubbs

Ian McCullough

Processing of fiber diffraction patterns is generally more difficult than for single-crystal patterns, and requires different algorithms and software. The program WCEN has been developed to determine experimental and specimen parameters and to convert diffraction data from detector to reciprocal space, and offers a variety of input and output formats, running under Mac OS X and Linux. The program is described and examples from oriented sols of filamentous plant viruses, illustrating different strategies for parameter determination and refinement, are given.