bluuebunny/crossref_metadata_2025_split huggingface dataset:
Reaction of nitrones with silyl ketene acetals: A DFT study
Authors: Milet Anne , Gimbert Yves , Greene Andrew E. 
Published: November 2005

AbstractTheoretical calculations at the DFT level indicate that the reaction of a nitrone with a silyl ketene acetal proceeds, contrary to previous suggestions, through a classical 1,3‐dipolar cycloaddition, followed by a silyl group transfer step to give the open‐chain product. Introduction of a diffuse basis set is necessary to describe properly nitrones. The influence of a Lewis acid has been studied. © 2005 Wiley Periodicals, Inc. J Comput Chem 27: 157–162, 2006
Revisiting the geometry of nd10 (n+1)s0 [M(H2O)]p+ complexes using four‐component relativistic DFT calculations and scalar relativistic correlated CSOV energy decompositions (Mp+ = Cu+, Zn2+, Ag+, Cd2+, Au+, Hg2+)
Authors: Gourlaouen Christophe , Piquemal Jean‐Philip , Saue Trond , Parisel Olivier 
Published: November 2005

AbstractHartree–Fock and DFT (B3LYP) nonrelativistic (scalar relativistic pseudopotentials for the metallic cation) and relativistic (molecular four‐component approach coupled to an all‐electron basis set) calculations are performed on a series of six nd10 (n+1)s0 [M(H2O)]p+ complexes to investigate their geometry, either planar C2v or nonplanar Cs. These complexes are, formally, entities originating from the complexation of a water molecule to a metallic cation: in the present study, no internal reorganization has been found, which ensures that the complexes can be regarded as a water molecule interacting with a metallic cation. For [Au(H2O)]+ and [Hg(H2O)]2+, it is observed that both electronic correlation and relativistic effects are required to recover the Cs structures predicted by the four‐component relativistic all‐electron DFT calculations. However, including the zero‐point energy corrections makes these shallow Cs minima vanish and the systems become floppy. In all other systems, namely [Cu(H2O)]+, [Zn(H2O)]2+, [Ag(H2O)]+, and [Cd(H2O)]2+, all calculations predict a C2v geometry arising from especially flat potential energy surfaces related to the out‐of‐plane wagging vibration mode. In all cases, our computations point to the quasi‐perfect transferability of the atomic pseudopotentials considered toward the molecular species investigated. A rationalization of the shape of the wagging potential energy surfaces (i.e., single well vs. double well) is proposed based on the Constrained Space Orbital Variation decompositions of the complexation energies. Any way of stabilizing the lowest unoccupied orbital of the metallic cation is expected to favor charge‐transfer (from the highest occupied orbital(s) of the water ligand), covalence, and, consequently, Cs structures. The CSOV complexation energy decompositions unambiguously reveal that such stabilizations are achieved by means of relativistic effects for [Au(H2O)]+, and, to a lesser extent, for [Hg(H2O)]2+. Such analyses allow to numerically quantify the rule of thumb known for Au+ which, once again, appears as a better archetype of a relativistic cation than Hg2+. This observation is reinforced due to the especially high contribution of the nonadditive correlation/relativity terms to the total complexation energy of [Au(H2O)]+. © 2005 Wiley Periodicals, Inc. J Comput Chem 27: 142–156, 2006
Prediction of spectroscopic constants for diatomic molecules in the ground and excited states using time‐dependent density functional theory
Authors: Falzon Chantal T. , Chong Delano P. , Wang Feng 
Published: November 2005

AbstractSpectroscopic constants of the ground and next seven low‐lying excited states of diatomic molecules CO, N2, P2, and ScF were computed using the density functional theory SAOP/ATZP model, in conjunction with time‐dependent density functional theory (TD‐DFT) and a recently developed Slater type basis set, ATZP. Spectroscopic constants, including the equilibrium distances re, harmonic vibrational frequency ωe, vibrational anharmonicity ωexe, rotational constant Be, centrifugal distortion constant De, the vibration–rotation interaction constant αe, and the vibrational zero‐point energy E were generated in an effort to establish a reliable database for electron spectroscopy. By comparison with experimental values and a similar model with an established larger Slater‐type basis set, et‐QZ3P‐xD, it was found that this model provides reliably accurate results at reduced computational costs, for both the ground and excited states of the molecules. The over all errors of all eight lowest lying electronic states of the molecules under study using the effective basis set are re(±4%), ωe(±5% mostly without exceeding ±20%), ωexe(±5% mostly without exceeding 20%, much more accurate than a previous study on this constant of ±30%), Be(±8%), De(±10%), αe(±10%), and E(±10%). The accuracy obtained using the ATZP basis set is very competitive to the larger et‐QZ3P‐xD basis set in particular in the ground electronic states. The overall errors in re, ωexe, and αe in the ground states were given by ±0.7, ±10.1, and ±8.4%, respectively, using the efficient ATZP basis set, which is competitive to the errors of ±0.5, ±9.2, and ±9.1%, respectively for those constants using the larger et‐QZ3P‐xD basis set. The latter basis set, however, needs approximately four times of the CPU time on the National Supercomputing Facilities (Australia). Due to the efficiency of the model (TD‐DFT, SAOP and ATZP), it will be readily applied to study larger molecular systems. © 2005 Wiley Periodicals, Inc. J Comput Chem 27: 163–173, 2006
Arsenite pre‐conditioning reduces UVB‐induced apoptosis in corneal epithelial cells through the anti‐apoptotic activity of 27 kDa heat shock protein (HSP27)
Authors: Shi Biao , Isseroff R. Rivkah 
Published: November 2005

AbstractExposure to ultraviolet (UV) light poses a health risk for eye disease, and solar ultraviolet in the B range (UVB, 280–320 nm) is known to be related to various corneal disorders. In this study, we investigated whether pre‐conditioning of cells with arsenite (AsO) can reduce UVB‐induced apoptosis in human corneal epithelial cells, and whether the anti‐apoptotic activity of 27 kDa heat shock protein (HSP27), a small heat shock protein, plays a role in this protection. UVB at levels comparable to physiologic solar exposure induces apoptosis of corneal epithelial cells in culture, demonstrated by activation of caspase 9 and caspase 3, and DNA fragmentation. When cells were pre‐conditioned with arsenite prior to UVB exposure, the UVB‐induced cell death was reduced, and UVB‐induced activation of caspases and DNA fragmentation was inhibited. When cells were pre‐treated with SB 203580, which inhibits HSP27 phosphorylation through inhibition of p38 MAP kinase activation, the arsenite‐induced reduction of UVB‐induced apoptosis was partially reversed. Arsenite pre‐conditioning inhibited UVB‐induced apoptosis in a two‐phase pattern, which was temporally correlated with arsenite‐induced HSP27 expression and phosphorylation. Neutralization of intracellular HSP27 with its antibody reduced arsenite's inhibition of UVB‐induced caspase3 activation. Our results suggest that forms of stress that upregulate HSP27 and its phosphorylation may be useful as novel approaches to prevent adverse ocular effects arising from UV exposure in humans. J. Cell. Physiol. 206: 563–563, 2006. © 2005 Wiley‐Liss, Inc.
Sustained and therapeutic levels of human factor IX in hemophilia B mice implanted with microcapsules: key role of encapsulated cells
Authors: Wen Jianping , Vargas Andrew Gómez , Ofosu Frederick A. , Hortelano Gonzalo 
Published: November 2005

AbstractBackgroundA gene therapy delivery system based on microcapsules enclosing recombinant cells engineered to secrete a therapeutic protein was explored in this study. In order to prevent immune rejection of the delivered cells, they were enclosed in non‐antigenic biocompatible alginate microcapsules prior to being implanted intraperitoneally into mice. We have shown that encapsulated C2C12 myoblasts can temporarily deliver therapeutic levels of factor IX (FIX) in mice, but the C2C12 myoblasts elicited an immune response to FIX. In this study we report the use of mouse fetal G8 myoblasts secreting hFIX in hemophilia mice.MethodsMouse G8 myoblasts were transduced with MFG‐FIX vector. A pool of recombinant G8 myoblasts secreting ∼1500 ng hFIX/106 cells/24 h in vitro were enclosed in biocompatible alginate microcapsules and implanted intraperitoneally into immunocompetent C57BL/6 and hemophilic mice.ResultsCirculating levels of hFIX in treated mice reached ∼400 ng/ml for at least 120 days (end of experiment). Interestingly, mice treated with encapsulated G8 myoblasts did not develop anti‐hFIX antibodies. Activated partial thromboplastin time (APTT) of plasmas obtained from treated hemophilic mice was reduced from 107 to 82 sec on day 60 post‐treatment, and whole blood clotting time (WBCT) was also corrected from 7–9 min before treatment to 3–5 min following microcapsule implantation. Further, mice were protected against bleeding following major trauma. Thus, the FIX delivery in vivo was biologically active.ConclusionsOur findings suggest that the type of cells encapsulated play a key role in the generation of immune responses against the transgene. Further, a judicious selection of encapsulated cells is critical for achieving sustained gene expression. Our findings support the feasibility of encapsulated G8 myoblasts as a gene therapy approach for hemophilia B. Copyright © 2005 John Wiley & Sons, Ltd.
Ultrastructural organization of the anal organs in the anal capsule of Craterostigmus tasmanianus Pocock, 1902 (Chilopoda, Craterostigmomorpha)
Authors: Rosenberg Jörg , Müller Carsten H.G. , Hilken Gero 
Published: November 2005

AbstractWe describe the ultrastructural organization of the anal organs of Craterostigmus tasmanianus, which are located on the ventral side of the bivalvular anal capsule. Each part of the capsule bears four pore fields with several anal pores. The pores lead into a pore canal, which is surrounded by the single‐layered epithelium of the anal organs. Each anal organ is composed of four different cell types: transporting cells of the main epithelium, junctional cells, isolated epidermal glands, and the cells forming the pore canal. The transporting cells exhibit infoldings of the outer cell membranes, forming a basal labyrinth and a poorly developed apical complex. The cells are covered by a specialized cuticle with a widened subcuticular layer. Only the cuticle of the main epithelium is covered by a mucous layer, secreted by the epidermal glands. The ultrastructural organization of the anal organ is comparable to the coxal and anal organs of other pleurostigmophoran Chilopoda. It is likely that the coxal and anal organs of the Pleurostigmophora are homologous, due to their identical ultrastructural organization. Differences concerning the location on the trunk of Pleurostigmophora are not sufficient to reject a hypothesis of homology. Anal organs are found not only in Craterostigmomorpha, but also in most adult Geophilomorpha, and in larvae and most adults of Lithobiomorpha. The anal organs of C. tasmanianus are thought to play an important role in the uptake of atmospheric water. J. Morphol. © 2005 Wiley‐Liss, Inc.
Base‐pairing potential identified by in vitro selection predicts the kinked RNA backbone observed in the crystal structure of the alfalfa mosaic virus RNA‐coat protein complex
Authors: Boyce Michael , Scott Felicia , Guogas Laura M. , Gehrke Lee 
Published: November 2005

AbstractThe three‐dimensional structure of the 3′ terminus of alfalfa mosaic virus RNA in complex with an amino‐terminal coat protein peptide revealed an unusual RNA fold with inter‐AUGC basepairing stabilized by key arginine residues (Guogas, et al., 2004). To probe viral RNA interactions with the full‐length coat protein, we have used in vitro genetic selection to characterize potential folding patterns among RNAs isolated from a complex randomized pool. Nitrocellulose filter retention, electrophoretic mobility bandshift analysis, and hydroxyl radical footprinting techniques were used to define binding affinities and to localize the potential RNA–protein interaction sites. Minimized binding sites were identified that included both the randomized domain and a portion of the constant regions of the selected RNAs. The selected RNAs, identified by their ability to bind full‐length coat protein, have the potential to form the same unusual inter‐AUGC Watson‐Crick base pairs observed in the crystal structure, although the primary sequences diverge from the wild‐type RNA. A constant feature of both the wild‐type RNA and the selected RNAs is a G ribonucleotide in the third position of an AUGC‐like repeat. Competitive binding assays showed that substituting adenosine for the constant guanosine in either the wild‐type or selected RNAs impaired coat protein binding. These data suggest that the interactions observed in the RNA–peptide structure are likely recapitulated when the full‐length protein binds. Further, the results underscore the power of in vitro genetic selection for probing RNA‐protein structure and function. Copyright © 2005 John Wiley & Sons, Ltd.
Anterior–inferior labral lesions of recurrent shoulder dislocation evaluated by MR arthrography in an adduction internal rotation (ADIR) position
Authors: Song Ho‐Taek , Huh Yong‐Min , Kim Sungjun , Lee Sung Ah , Kim Sung‐Jae , Shin Kyoo‐Ho , Suh Jin‐Suck 
Published: November 2005

AbstractPurposeTo introduce and evaluate the usefulness of the adduction internal rotation (ADIR) position in MR arthrography for discriminating the following subtypes of Bankart lesions: classic Bankart lesions, anterior labroligamentous periosteal sleeve avulsion (ALPSA) lesions, and Perthes lesions.Materials and MethodsThe study group consisted of 25 patients who had been referred for MR arthrography of the shoulder and then underwent arthroscopy due to recurrent episodes of shoulder dislocation. MR arthrography was performed in three different positions: neutral, abduction external rotation (ABER), and ADIR. The authors evaluated the statistical significance of the method's discriminative diagnostic ability for the subtypes of Bankart lesions according to the position changes.ResultsTwenty‐three patients had the following single or complex labral lesions: classic Bankart (N = 8), ALPSA (N = 3), complex classic Bankart/ALPSA (N = 8), and complex ALPSA/Perthes (N = 4). Two patients had no visible anteroinferior labral lesions. The performance of ADIR positioning for differentiating ALPSA lesions was superior to the neutral or ABER positioning. The difference of the discriminative lesion detection ability was statistically significant (P <.01) only for detecting ALPSA lesions in the ADIR position.ConclusionMR arthrography in the ADIR position provides high accuracy for the diagnosis of ALPSA lesions, and complements routine MR arthrography when used to diagnose labroligamentous lesions in patients with recurrent shoulder dislocations. J. Magn. Reson. Imaging 2006. © 2005 Wiley‐Liss, Inc.
Relaxation times of breast tissue at 1.5T and 3T measured using IDEAL
Authors: Rakow‐Penner Rebecca , Daniel Bruce , Yu Huanzhou , Sawyer‐Glover Anne , Glover Gary H. 
Published: November 2005

AbstractPurpose:To accurately measure T1 and T2 of breast fibroglandular tissue and fat at 1.5T and 3T, and note the partial volume effects of the admixture of fibroglandular tissue and fat on the relaxation rates using an approach termed iterative decomposition of water and fat with echo asymmetry and least squares estimation (IDEAL) imaging.Materials and Methods:T1 and T2 values were measured on the right breasts of five healthy women at 1.5T and 3T. T1 data were collected using two sequences: inversion recovery without IDEAL, and inversion recovery with IDEAL. T2 data were collected using Hahn Echo scans. SNR and CNR analyses were conducted on collected data.Results:T1 increased for both fat (21%) and glandular tissue (17%) from 1.5T to 3T. Thus, the TR and TI of breast protocols at 3T should be lengthened accordingly. SNR more than doubled for both tissue types from 1.5T to 3T. IDEAL imaging demonstrated the partial volume effects of fat and glandular tissue on measuring relaxation rates of independent tissue types.Conclusion:With separated fat and water images, more precise measurements can be made for the lipid component in fat, and the water component in fibroglandular tissue. J. Magn. Reson. Imaging 2006. © 2005 Wiley‐Liss, Inc.
Fat‐suppressed three‐dimensional dual echo dixon technique for contrast agent enhanced MRI
Authors: Ma Jingfei , Vu Anthony T. , Son Jong Bum , Choi Haesun , Hazle John D. 
Published: November 2005

AbstractPurposeTo develop a fast T1‐weighted, fat‐suppressed three‐dimensional dual echo Dixon technique and to demonstrate its use in contrast agent enhanced MRI.Materials and MethodsA product fast three‐dimensional gradient echo pulse sequence was modified to acquire dual echoes after each RF excitation with water and fat signals in‐phase (IP) and opposed‐phase (OP), respectively. An on‐line reconstruction algorithm was implemented to automatically generate separate water and fat images. The signal to noise ratio (SNR) of the new technique was compared to that of the product technique in phantom. In vivo abdomen and breast images of cancer patients were acquired at 1.5 Tesla using both techniques before and after intravenous administration of gadolinium contrast agent.ResultsIn phantom, the new technique yields a close to the theoretically predicted 41% increase in SNR in comparison to the product technique without fat suppression (FS). In vivo images of the new technique show noticeably improved FS and image quality in comparison to the images acquired of the same patients using the product technique with FS.ConclusionThe three‐dimensional dual echo Dixon technique provides excellent image quality and can be used for T1‐weighted, fat‐suppressed imaging with contrast agent injection. J. Magn. Reson. Imaging 2006. © 2005 Wiley‐Liss, Inc.
Zero filled partial fourier phase contrast MR imaging: In vitro and in vivo assessment
Authors: Szarf Gilberto , Dori Yoav , Rettmann Dan , Tekes Aylin , Nasir Khurram , Amado Luciano , Foo Thomas K.F. , Bluemke David A. 
Published: November 2005

AbstractPurposeTo validate partial Fourier phase contrast magnetic resonance (PC MR) with full number of excitation (NEX) PC MR measurements in vitro and in vivo.Materials and MethodsMR flow measurements were performed using a partial Fourier and a full NEX PC MR sequence in a flow phantom and in 10 popliteal and renal arteries of 10 different healthy volunteers. Average velocity, peak velocity, and flow results were calculated and compared with regression analysis.ResultsExcellent correlations in average velocities (r = 0.99, P < 0.001), peak velocities (r = 0.99, P < 0.001), and flow rates (r = 0.98, P < 0.001) were demonstrated in vitro between the two different acquisitions. For the popliteal arteries there was excellent correlation between peak velocities for both acquisitions (r = 0.98, P < 0.0001); the correlation of average velocity measurements when using all data points in the cardiac cycle for all volunteers was 0.96 (P < 0.001). For the renal arteries the same comparison resulted in a good correlation for average velocity (0.93, P < 0.001) and peak velocity measurements (r = 0.91, P = 0.002), although the correlation coefficient for flow rates was 0.88 (P = 0.004). Blurring of the vessel margins was consistently observed on magnitude images acquired with the partial Fourier method, causing overestimation of the vessel area and some error in the flow measurements.ConclusionPartial Fourier PC MR is able to provide comparable average and peak velocity values when using 1 NEX PC MRI as a reference. J. Magn. Reson. Imaging 2006. © 2005 Wiley‐Liss, Inc.
A case of mesenteric cystic lymphangioma: Fat saturation and chemical shift MR imaging
Authors: Yoo Eunhye , Kim Myeong‐Jin , Kim Ki Whang , Chung Jae‐Joon , Kim Seung Hyoung , Choi Jin‐Young 
Published: November 2005

AbstractMesenteric cystic lymphangioma is an uncommon lesion that may be difficult to diagnose radiologically. In our case, a septate cystic mass showed fluid attenuation on a computed tomography scan. We were able to define the fat content within the cystic tumor by magnetic resonance (MR) imaging. The presence of fat within an intra‐abdominal cystic mass is suggestive of a dermoid cyst, cystic lymphangioma, or lymphocele. The pathologic diagnosis revealed a cystic lymphangioma, which originated from the mesentery. Although the MR imaging features of dermoid cysts and lymphangiomas are well known, the demonstration of fat content by chemical shift and fat saturation MRI has not yet been reported for a cystic lymphangioma. J. Magn. Reson. Imaging 2006. © 2005 Wiley‐Liss, Inc.
MRI‐compatible incubation chamber for cell culture experiments
Authors: Schwenzer Nina F. , Grönewäller Eckart F. , Rodegerdts Enno , Kehlbach Rainer , Duda Stephan H. , Claussen Claus D. 
Published: November 2005

AbstractPurposeTo develop an incubation chamber that is compatible with MRI, while avoiding sources of error due to the experimental setup.Materials and MethodsTwo identical and gas‐tight chambers were constructed of Plexiglas™. The temperature and the CO2 concentration were adjustable. Temperature variations within and between both chambers were measured. The pH values of the cell culture media were measured under different environmental settings. For each environment a colony formation test was carried out. The homogeneity of the magnetic field inside the chambers was estimated by phantom tests.ResultsThe temperature variations within the chambers were <0.3°C, and the variation between the chambers was on average <0.05°C. After eight hours the pH values of the cell culture media were 7.47 and 7.48 in the reference and measurement chambers, respectively; 7.41 in the CO2 incubator; and 8.73 in ambient air. In colony formation tests the survival fraction in the Plexiglas™ chamber was comparable to that in the CO2 incubator. No distortions of the magnetic field from the incubation chamber were observed.ConclusionThe incubation system presented can provide the conditions of a CO2 incubator without alteration of the magnetic flux density. J. Magn. Reson. Imaging 2006. © 2005 Wiley‐Liss, Inc.
Reduction or delay of post‐harvest physiological deterioration in cassava roots with higher carotenoid content
Authors: Sánchez T , Chávez AL , Ceballos H , Rodriguez‐Amaya DB , Nestel P , Ishitani M 
Published: November 2005

AbstractPost‐harvest physiological deterioration (PPD) is one of the most important constraints in cassava production and commercialization. It has been hypothesized that the antioxidant properties of carotenoids in yellow cassava roots may help reduce or delay PPD. The industrial sector prefers cassava with a high dry matter content. The latter has also been reported to have a positive correlation with PPD. The objective of this study was to determine the correlation between both the dry matter and total carotenoid contents and PPD in the roots of 101 cassava clones. PPD was positively but weakly associated with dry matter content (R2= 0.100,P< 0.01), and inversely associated with the total carotenoid content in roots (R2= 0.515,P< 0.01). In addition, total carotenoid content and color intensity were strongly and positively associated (R2= 0.769,P< 0.01), suggesting that the roots of cassava clones with a relatively high total carotenoid content can be selected through a simple visual inspection of the color intensity in the parenchyma. Copyright © 2005 Society of Chemical Industry