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Full-Text Articles in Social and Behavioral Sciences
Specific Cellular Water Dynamics Observed In Vivo By Neutron Scattering And Nmr., Moeava Tehei, Marion Jasnin, Andreas Stadler, Giuseppe Zaccai
Specific Cellular Water Dynamics Observed In Vivo By Neutron Scattering And Nmr., Moeava Tehei, Marion Jasnin, Andreas Stadler, Giuseppe Zaccai
Faculty of Science - Papers (Archive)
Neutron scattering, by using deuterium labelling, revealed how intracellular water dynamics, measured in vivo in E. coli, human red blood cells and the extreme halophile, Haloarcula marismortui, depends on the cell type and nature of the cytoplasm. The method uniquely permits the determination of motions on the molecular length (Ba˚ ngstrøm) and time (pico- to nanosecond) scales. In the bacterial and human cells, intracellular water beyond the hydration shells of cytoplasmic macromolecules and membrane faces flows as freely as liquid water. It is not ‘‘tamed’’ by confinement. In contrast, in the extreme halophile archaeon, in addition to free and hydration …
Structures, Biological Activities And Phylogenetic Relationships Of Terpenoids From Marine Ciliates Of The Genus Euplotes, Graziano Guella, Danielle Skropeta, Graziano Di Giuseppe, Fernando Dini
Structures, Biological Activities And Phylogenetic Relationships Of Terpenoids From Marine Ciliates Of The Genus Euplotes, Graziano Guella, Danielle Skropeta, Graziano Di Giuseppe, Fernando Dini
Faculty of Science - Papers (Archive)
In the last two decades, large scale axenic cell cultures of the marine species comprising the family Euplotidae have resulted in the isolation of several new classes of terpenoids with unprecedented carbon skeletons including the (i) euplotins, highly strained acetylated sesquiterpene hemiacetals; (ii) raikovenals, built on the bicyclo[3.2.0]heptane ring system; (iii) rarisetenolides and focardins containing an octahydroazulene moiety; and (iv) vannusals, with a unique C-30 backbone. Their complex structures have been elucidated through a combination of nuclear magnetic resonance spectroscopy, mass spectrometry, molecular mechanics and quantum chemical calculations. Despite the limited number of biosynthetic experiments having been performed, the large …
Learning How To Be An Academic - The Story Of A New Academic In The Sciences, Danielle Skropeta
Learning How To Be An Academic - The Story Of A New Academic In The Sciences, Danielle Skropeta
Faculty of Science - Papers (Archive)
No abstract provided.
Average Mass Scan Of The Total Ion Chromatogram Versus Percentage Chemical Composition In Multivariate Statistical Comparison Of Complex Volatile Mixtures, Niko Radulovic, Polina Blagojevic, Danielle Skropeta
Average Mass Scan Of The Total Ion Chromatogram Versus Percentage Chemical Composition In Multivariate Statistical Comparison Of Complex Volatile Mixtures, Niko Radulovic, Polina Blagojevic, Danielle Skropeta
Faculty of Science - Papers (Archive)
The analysis of complex volatile mixtures by gas chromatography-mass spectrometry (GC-MS) is a time-consuming process. It involves separation and identification of the components based on their retention times and fragmentation patterns, followed by determination of their relative percentages from integration of their peak areas. Herein we show that multivariate statistical analysis of the relative abundances of the m/z values obtained from the average mass scans (AMS) of the complex mixture is a faster and potentially more reliable method of assessing these mixtures. To achieve this, 15 model complex mixtures, were prepared comprising varying amounts of 10 different constituents. The AMS …
Hydration Dependent Studies Of Highly Aligned Multilayer Lipid Membranes By Neutron Scattering , Marcus Trapp, Thomas Gutberlet, Fanni Juranyi, T Unruh, Bruno Demé, Moeava Tehei, Judith Peters
Hydration Dependent Studies Of Highly Aligned Multilayer Lipid Membranes By Neutron Scattering , Marcus Trapp, Thomas Gutberlet, Fanni Juranyi, T Unruh, Bruno Demé, Moeava Tehei, Judith Peters
Faculty of Science - Papers (Archive)
We investigated molecular motions on a picoseconds timescale of 1,2-Dimyristoyl-sn- Glycero-3-Phosphocholine (DMPC) model membranes as a function of hydration by using elastic and quasielastic neutron scattering. Two different hydrations corresponding to approximately nine and twelve water molecules per lipid were studied, the latter being the fully hydrated state. In our study we focused on head group motions by using chain deuterated lipids. Information on in-plane and out-of-plane motions could be extracted by using solid supported DMPC multilayers. Our studies confirm and complete former investigations by K¨onig et al. and Rheinst¨adter et al. who describe the dynamics of lipidmembranes, but did …
Myriocin-Mediated Up-Regulation Of Hepatocyte Apoa-I Synthesis Is Associated With Erk Inhibition, Elias N. Glaros, Woojin Scott Kim, Brett Garner
Myriocin-Mediated Up-Regulation Of Hepatocyte Apoa-I Synthesis Is Associated With Erk Inhibition, Elias N. Glaros, Woojin Scott Kim, Brett Garner
Faculty of Science - Papers (Archive)
Sphingolipids including sphingomyelin have been implicated as potential atherogenic lipids. Studies in apoE (apolipoprotein E)-null mice have revealed that the serine palmitoyltransferase inhibitor myriocin reduces plasma levels of sphingomyelin, ceramide, sphingosine-I-phosphate and glycosphingolipids and that this is associated with potent inhibition of atherosclerosis. Interestingly, hepatic apoA-I (apolipoprotein A-I) synthesis and plasma HDL (high-density lipoprotein)cholesterol levels were also increased in apoE-null mice treated with myriocin. Since myriocin is a known inhibitor of ERK (extracellular-signal-related kinase) phosphorylation, we assessed the possibility that myriocin may be acting to increase hepatic apoA-I production via this pathway. To address this, HepG2 cells and primary mouse …
Total Synthesis Of Uniflorine A, Casuarine, Australine, 3-Epi-Australine, And 3,7-Di-Epi-Australine From A Common Precursor, Thunwadee Ritthiwigrom, Anthony C. Willis, Stephen G. Pyne
Total Synthesis Of Uniflorine A, Casuarine, Australine, 3-Epi-Australine, And 3,7-Di-Epi-Australine From A Common Precursor, Thunwadee Ritthiwigrom, Anthony C. Willis, Stephen G. Pyne
Faculty of Science - Papers (Archive)
A flexible method for the diastereoselective total synthesis of the pyrrolizidine alkaloids Uniflorine A, casuarine, australine, and 3-epi-australine and the unnatural epimer 3,7-di-epi-australine from a common chiral 2,5-dihydropyrrole precursor is described.
Parameters Governing Invasive Disease Propensity Of Non-M1 Serotype Group A Streptococci, Peter G. Maamary, Martina L. Sanderson-Smith, Ramy K. Aziz, Andrew Hollands, Jason N. Cole, Fiona C. Mckay, Jason D. Mcarthur, Joshua K. Kirk, Amanda J. Cork, Rachael J. Keefe, Rita G. Kansal, Hongmin Sun, William L. Taylor, Gursharan S. Chhatwal, David Ginsburg, Victor Nizet, Malak Kotb, Mark J. Walker
Parameters Governing Invasive Disease Propensity Of Non-M1 Serotype Group A Streptococci, Peter G. Maamary, Martina L. Sanderson-Smith, Ramy K. Aziz, Andrew Hollands, Jason N. Cole, Fiona C. Mckay, Jason D. Mcarthur, Joshua K. Kirk, Amanda J. Cork, Rachael J. Keefe, Rita G. Kansal, Hongmin Sun, William L. Taylor, Gursharan S. Chhatwal, David Ginsburg, Victor Nizet, Malak Kotb, Mark J. Walker
Faculty of Science - Papers (Archive)
Group A Streptococcus (GAS) causes rare but life-threatening syndromes of necrotizing fasciitis and toxic shock-like syndrome in humans. The GAS serotype M1T1 clone has globally disseminated, and mutations in the control of virulence regulatory sensor kinase (covRS) operon correlate with severe invasive disease. Here, a cohort of non-M1 GAS was screened to determine whether mutation in covRS triggers systemic dissemination in divergent M serotypes. A GAS disease model defining parameters governing invasive propensity of differing M types is proposed. The vast majority of GAS infection is benign. Nonetheless, many divergent M types possess limited capacity to cause invasive infection. Mill …
Phytochemical Investigations Of Stemona Curtisii And Synthetic Studies On Stemocurtisine Alkaloids, Sukanda Chaiyong, Araya Jatisatienr, Pitchaya Mungkornasawakul, Thanapat Sastraruji, Stephen G. Pyne, Alison T. Ung, Thitima Urathamakul, Wilford Lie
Phytochemical Investigations Of Stemona Curtisii And Synthetic Studies On Stemocurtisine Alkaloids, Sukanda Chaiyong, Araya Jatisatienr, Pitchaya Mungkornasawakul, Thanapat Sastraruji, Stephen G. Pyne, Alison T. Ung, Thitima Urathamakul, Wilford Lie
Faculty of Science - Papers (Archive)
The isolation of two new Stemona alkaloids, 1-hydroxyprotostemonine and stemocurtisine N-oxide, and a new benzofuran, stemofuran L, from the root extracts of Stemona curtisii is reported. The major known alkaloids from this plant extract, stemocurtisine, stemocurtisinol, and oxyprotostemonine, were also isolated along with oxystemokerrine N-oxide. The nonalkaloid components of this extract included a new benzofuran derivative, stemofuran L, the known stemofurans F, J, and K, dihydro-γ-tocopherol, and stigmasterol. Stemocurtisine and stemocurtisinol were converted to their respective N-oxides by oxidation. Stemocurtisine was converted to a tetracyclic derivative by oxidative cleavage of the γ-butyrolactone ring, while stemocurtisinol gave a novel lactam derivative …
The First Syntheses Of Enantiopure 2,2 '-Biindoline, Steven M. Wales, Anthony C. Willis, Paul A. Keller
The First Syntheses Of Enantiopure 2,2 '-Biindoline, Steven M. Wales, Anthony C. Willis, Paul A. Keller
Faculty of Science - Papers (Archive)
The first two syntheses of chiral 2,2'-biindoline are reported either in five steps from 2,2'-bioxirane, or three steps from 2,2'-biaziridine, both with exceptional enantiopurity
A Combined Experimental And Theoretical Study Of Ion Solvation In Liquid N-Methylacetamide, Haibo Yu, Christopher L. Mazzanti, Troy W. Whitfield, Roger E. Koeppe Ii, Olaf S. Andersen, Benoit Roux
A Combined Experimental And Theoretical Study Of Ion Solvation In Liquid N-Methylacetamide, Haibo Yu, Christopher L. Mazzanti, Troy W. Whitfield, Roger E. Koeppe Ii, Olaf S. Andersen, Benoit Roux
Faculty of Science - Papers (Archive)
Most current biomolecular simulations are based on potential energy functions that treat the electrostatic energy as a sum of pairwise Coulombic interactions between effective fixed atomic charges. This approximation, in which many-body induced polarization effects are included in an average way, is expected to be satisfactory for a wide range of systems, but less accurate for processes involving the transfer and partition of ions among heterogeneous environments. The limitations of these potential energy functions are perhaps most obvious in studies of ion permeation through membrane channels. In many cases, the pore is so narrow that the permeating ion must shed …
Assessing The Accuracy Of Approximate Treatments Of Ion Hydration Based On Primitive Quasichemical Theory, Benoit Roux, Haibo Yu
Assessing The Accuracy Of Approximate Treatments Of Ion Hydration Based On Primitive Quasichemical Theory, Benoit Roux, Haibo Yu
Faculty of Science - Papers (Archive)
Quasichemical theory (QCT) provides a framework that can be used to partition the influence of the solvent surrounding an ion into near and distant contributions. Within QCT, the solvation properties of the ion are expressed as a sum of configurational integrals comprising only the ion and a small number of solvent molecules. QCT adopts a particularly simple form if it is assumed that the clusters undergo only small thermal fluctuations around a well-defined energy minimum and are affected exclusively in a mean-field sense by the surrounding bulk solvent. The fluctuations can then be integrated out via a simple vibrational analysis, …
Identification Of Human Plasma Proteins As Major Clients For The Extracellular Chaperone Clusterin, Amy R. Wyatt, Mark R. Wilson
Identification Of Human Plasma Proteins As Major Clients For The Extracellular Chaperone Clusterin, Amy R. Wyatt, Mark R. Wilson
Faculty of Science - Papers (Archive)
Clusterin (CLU) is an extracellular chaperone that is likely to play an important role in protein folding quality control. This study identified three deposition disease-associated proteins as major plasma clients for clusterin by studying CLU-client complexes formed in response to physiologically relevant stress (shear stress, similar to 36 dynes/cm(2) at 37 degrees C). Analysis of plasma samples by size exclusion chromatography indicated that (i) relative to control plasma, stressed plasma contained proportionally more soluble protein species of high molecular weight, and (ii) high molecular weight species were far more abundant when proteins purified by anti-CLU immunoaffinity chromatography from stressed plasma …
The Two-Faced Nature Of Small Heat Shock Proteins: Amyloid Assembly And The Inhibition Of Fibril Formation. Relevance To Disease States, Heath W. Ecroyd, S Meehan, John A. Carver
The Two-Faced Nature Of Small Heat Shock Proteins: Amyloid Assembly And The Inhibition Of Fibril Formation. Relevance To Disease States, Heath W. Ecroyd, S Meehan, John A. Carver
Faculty of Science - Papers (Archive)
The ability of small heat-shock proteins (sHsps) such as alphaB-crystallin to inhibit the amorphous (disordered) aggregation of varied target proteins in a chaperone-like manner has been well described. The mechanistic details of this action are not understood. Amyloid fibril formation is an alternative off-folding pathway that leads to highly ordered beta-sheet-containing aggregates. Amyloid fibril formation is associated with a broad range of protein conformational diseases such as Alzhiemer's, Parkinson's and Huntington's and sHsp expression is elevated in the protein deposits that are characteristic of these disease states. The ability of sHsps to prevent fibril formation has been less well characterised. …
Toxicity To Melita Plumulosa From Intermittent And Continuous Exposures To Dissolved Copper, Brad M. Angel, Stuart L. Simpson, Dianne F. Jolley
Toxicity To Melita Plumulosa From Intermittent And Continuous Exposures To Dissolved Copper, Brad M. Angel, Stuart L. Simpson, Dianne F. Jolley
Faculty of Science - Papers (Archive)
The concentrations of metal contaminants often fluctuate in estuarine waters; yet we have limited knowledge about the effects of intermittent exposures on estuarine organisms. Using 10-d lethality bioassays with the epibenthic amphipod Melita plumulosa, different combinations of intermittent (pulsed) dissolved Cu exposure were investigated, varying Cu concentration, pulse duration, and time between pulses. Negligible organism mortality was observed immediately after single 12- to 62-h duration pulsed exposures of 100 to 900 mg/L dissolved Cu. However, delayed mortality was observed in the subsequent 96-h nonexposure period, after which negligible additional mortality occurred during the remainder of the 240-h tests. For multiple …
Preclinical Evaluation Of Novel All-In-One Formulations Of 5-Fluorouracil And Folinic Acid With Reduced Toxicity Profiles - Supplementary Data, Tamantha K. Stutchbury, Kara L. Vine, Julie M. Locke, Jeremy S. Chrisp, J. B. Bremner, P Clingan, Marie Ranson
Preclinical Evaluation Of Novel All-In-One Formulations Of 5-Fluorouracil And Folinic Acid With Reduced Toxicity Profiles - Supplementary Data, Tamantha K. Stutchbury, Kara L. Vine, Julie M. Locke, Jeremy S. Chrisp, J. B. Bremner, P Clingan, Marie Ranson
Faculty of Science - Papers (Archive)
Objectives: 5-Fluorouracil (5-FU) in combination with its synergistic biomodulator folinic acid maintains a pivotal position in cancer chemotherapy. However, clinical limitations persist with the administration of these drugs in combination including phlebitis and catheter blockages, which are associated with reduced efficacy and/or quality of life for patients. We have previously reported novel all-in-one, pH neutral, parenteral 5-FU and folinic acid formulations (termed Fluorodex) incorporating beta-cyclodextrins. Fluorodex maintains potency while overcoming the accepted incompatibility of 5-FU and folinic acid.
Methods: We performed toxicological, pharmacokinetic and biodistribution, and efficacy evaluations of Fluorodex compared to 5-FU:folinic acid using several administration routes …
Elastic Scattering Studies Of Aligned Dmpc Multilayers On Different Hydrations, Marcus Trapp, Fanni Juranyi, Moeava Tehei, Lambert Van Eijck, Bruno Demé, Thomas Gutberlet, Judith Peters
Elastic Scattering Studies Of Aligned Dmpc Multilayers On Different Hydrations, Marcus Trapp, Fanni Juranyi, Moeava Tehei, Lambert Van Eijck, Bruno Demé, Thomas Gutberlet, Judith Peters
Faculty of Science - Papers (Archive)
Biological membranes, consisting mainly of phospholipids and proteins, are organized in a bilayered structure which exhibits dynamical behaviour within time regimes ranging from 10-12 s with the motion of alkyl chain defects and 1 s corresponding to collective excitations of the bilayer [1]. With the prominent role hydration plays on the structural phase behaviour of phospholipids membranes, it is essential for a better description of membranes to understand also the influence of hydration on the dynamics of membrane systems. In the present study we have performed neutron scattering investigations on highly oriented DMPC-d54 multilayers at two different relative humidity (rh) …
Essential Biological Processes Of An Emerging Pathogen: Dna Replication, Transcription, And Cell Division In Acinetobacter Spp., Andrew Robinson, Anthony J. Brzoska, Kylie M. Turner, Ryan Withers, Elizabeth J. Harry, Peter J. Lewis, Nicholas E. Dixon
Essential Biological Processes Of An Emerging Pathogen: Dna Replication, Transcription, And Cell Division In Acinetobacter Spp., Andrew Robinson, Anthony J. Brzoska, Kylie M. Turner, Ryan Withers, Elizabeth J. Harry, Peter J. Lewis, Nicholas E. Dixon
Faculty of Science - Papers (Archive)
Species of the bacterial genus Acinetobacter are becoming increasingly important as a source of hospital-acquired infections (31, 185, 204). Acinetobacter spp. are ubiquitous nonmotile gammaproteobacteria, typified by metabolic versatility and a capacity for natural transformation (172, 204). The species of most clinical relevance is A. baumannii; however, pathogenic strains of A. lwoffi and A. baylyi have also been described (38, 185, 215).
The Quaternary Organization And Dynamics Of The Molecular Chaperone Hsp26 Are Thermally Regulated, J. L. Benesch, Andrew Aquilina, Andrew Baldwin, Agata Rekas, Florian Stengel, Robyn Lindner, Eman Basha, G. Devlin, J. Horwitz, Elizabeth Vierling, John Carver, C. V. Robinson
The Quaternary Organization And Dynamics Of The Molecular Chaperone Hsp26 Are Thermally Regulated, J. L. Benesch, Andrew Aquilina, Andrew Baldwin, Agata Rekas, Florian Stengel, Robyn Lindner, Eman Basha, G. Devlin, J. Horwitz, Elizabeth Vierling, John Carver, C. V. Robinson
Faculty of Science - Papers (Archive)
The function of ScHSP26 is thermally controlled: the heat shock that causes the destabilization of target proteins leads to its activation as a molecular chaperone. We investigate the structural and dynamical properties of ScHSP26 oligomers through a combination of multiangle light scattering, fluorescence spectroscopy, NMR spectroscopy, and mass spectrometry. We show that ScHSP26 exists as a heterogeneous oligomeric ensemble at room temperature. At heat-shock temperatures, two shifts in equilibria are observed: toward dissociation and to larger oligomers. We examine the quaternary dynamics of these oligomers by investigating the rate of exchange of subunits between them and find that this not …