bluuebunny/crossref_metadata_2025_split huggingface dataset:
Non‐invasive in vivo imaging of vessel calibre in orthotopic prostate tumour xenografts
Authors: Walker‐Samuel Simon , Boult Jessica K.R. , McPhail Lesley D. , Box Gary , Eccles Suzanne A. , Robinson Simon P. 
Published: April 2011

AbstractSusceptibility contrast magnetic resonance imaging (MRI), utilising ultrasmall superparamagnetic iron oxide (USPIO) particles, was evaluated for the quantitation of vessel size index (Rv, μm), a weighted average measure of tumour blood vessel calibre, and fractional tumour blood volume (fBV, %), in orthotopically propagated murine PC3 prostate tumour xenografts. Tumour vascular architecture was assessed in vivo by MRI prior to and 24 hr after treatment with 200 mg/kg of the vascular disrupting agent ZD6126. A Bayesian hierarchical model (BHM) was used to reduce the uncertainty associated with quantitation of Rv and fBV. Quantitative histological analyses of the uptake of Hoechst 33342 for perfused vasculature, and haematoxylin and eosin staining for necrosis, were also performed to qualify the MRI data. A relatively large median Rv of 40.3 μm (90% confidence interval (CI90) = 37.4, 44.0 μm) and a high fBV of 5.4% (CI90 = 5.3, 5.5%) were determined in control tumours, which agreed with histologically determined vessel size index. Treatment with ZD6126 significantly (p < 0.01) reduced tumour Rv (34.2μm, CI90 = 31.2, 38.0 μm) and fBV (3.9%, CI90 = 3.8, 4.1%), which were validated against histologically determined significant reductions in perfusion and vessel size, and increased necrosis. Together these data (i) highlight the use of a BHM to optimise the inferential power available from susceptibility contrast MRI data, (ii) provide strong evaluation and qualification of Rv and fBV as non‐invasive imaging biomarkers of tumour vascular morphology, (iii) reveal the presence of a different vascular phenotype and (iv) demonstrate that ZD6126 exhibits good anti‐vascular activity against orthotopic prostate tumours.
Peroxotitanate‐ and monosodium metal‐titanate compounds as inhibitors of bacterial growth
Authors: Chung Whasun O. , Wataha John C. , Hobbs David T. , An Jonathan , Wong Jacqueline J. , Park Christine H. , Dogan Sami , Elvington Mark C. , Rutherford R. Bruce 
Published: April 2011

AbstractSodium titanates are ion‐exchange materials that effectively bind a variety of metal ions over a wide pH range. Sodium titanates alone have no known adverse biological effects but metal‐exchanged titanates (or metal titanates) can deliver metal ions to mammalian cells to alter cell processes in vitro. In this work, we test a hypothesis that metal‐titanate compounds inhibit bacterial growth; demonstration of this principle is one prerequisite to developing metal‐based, titanate‐delivered antibacterial agents. Focusing initially on oral diseases, we exposed five species of oral bacteria to titanates for 24 h, with or without loading of Au(III), Pd(II), Pt(II), and Pt(IV), and measuring bacterial growth in planktonic assays through increases in optical density. In each experiment, bacterial growth was compared with control cultures of titanates or bacteria alone. We observed no suppression of bacterial growth by the sodium titanates alone, but significant (p < 0.05, two‐sided t‐tests) suppression was observed with metal‐titanate compounds, particularly Au(III)‐titanates, but with other metal titanates as well. Growth inhibition ranged from 15 to 100% depending on the metal ion and bacterial species involved. Furthermore, in specific cases, the titanates inhibited bacterial growth 5‐ to 375‐fold versus metal ions alone, suggesting that titanates enhanced metal–bacteria interactions. This work supports further development of metal titanates as a novel class of antibacterials. © 2011 Wiley Periodicals, Inc. J Biomed Mater Res Part A:, 2011.
Performance of six functionals (LDA, PBE, PBESOL, B3LYP, PBE0, and WC1LYP) in the simulation of vibrational and dielectric properties of crystalline compounds. The case of forsterite Mg2SiO4
Authors: De La Pierre M. , Orlando R. , Maschio L. , Doll K. , Ugliengo P. , Dovesi R. 
Published: April 2011

AbstractThe performance of six different density functionals (LDA, PBE, PBESOL, B3LYP, PBE0, and WC1LYP) in describing the infrared spectrum of forsterite, a crystalline periodic system with orthorhombic unit cell (28 atoms in the primitive cell, Pbmn space group), is investigated by using the periodic ab initio CRYSTAL09 code and an all‐electron Gaussian‐type basis set. The transverse optical (TO) branches of the 35 IR active modes are evaluated at the equilibrium geometry together with the oscillator strengths and the high‐frequency dielectric tensor ϵ∞. These quantities are essential to compute the dielectric function ϵ(ν), and then the reflectance spectrum R(ν), which is compared with experiment. It turns out that hybrid functionals perform better than LDA and GGA, in general; that B3LYP overperforms WC1LYP and, in turn, PBE0; that PBESOL is better than PBE; that LDA is the worst performing functional among the six under study. © 2011 Wiley Periodicals, Inc. J Comput Chem, 2011
Role of bridging water molecules in GSK3β‐inhibitor complexes: Insights from QM/MM, MD, and molecular docking studies
Authors: Lu Shao‐Yong , Jiang Yong‐Jun , Lv Jing , Zou Jian‐Wei , Wu Tian‐Xing 
Published: April 2011

AbstractThe role of water molecules is increasingly gaining interest in drug design, and several studies have highlighted their paramount contributions to the specificity and the affinity of ligand binding. In this study, we employ the two‐layer ONIOM‐based quantum mechanics/molecular mechanics (QM/MM) calculations, molecular dynamics (MD) simulations, and molecular docking studies to investigate the effect of bridging water molecules at the GSK3β‐inhibitors interfaces. The results obtained from the ONIOM geometry optimization and AIM analysis corroborated the presence of bridging water molecules that form hydrogen bonds with protein side chain of Thr138 and/or backbone of Gln185, and mediate interactions with inhibitors in the 10 selected GSK3β‐inhibitor complexes. Subsequently, MD simulations carried out on a representative system of 1R0E demonstrated that the bridging water molecule is stable at the GSK3β‐inhibitor interface and appears to contribute to the stability of the protein–inhibitor interactions. Furthermore, molecular docking studies of GSK3β‐inhibitor complexes indicated that the inhibitors can increase binding affinities and the better docked conformation of inhibitors can be obtained by inclusion of the bridging water molecules, especially for the flexible inhibitors, in docking experiments into individual protein conformations. Our results elucidate the importance of bridging water molecules at the GSK3β‐inhibitor interfaces and suggest that they might prove useful in rational drug design. © 2011 Wiley Periodicals, Inc. J Comput Chem, 2011
Homocysteine mediated decrease in bone blood flow and remodeling: Role of folic acid
Authors: Tyagi Neetu , Kandel Madhavi , Munjal Charu , Qipshidze Natia , Vacek Jonathan C. , Pushpakumar Sathnur B. , Metreveli Naria , Tyagi Suresh C. 
Published: April 2011

AbstractDeficiencies in folate lead to increased serum concentrations of homocysteine (Hcy), which is known as hyperhomocysteinemia (HHcy), is associated with bone disorders. Although, Hcy accumulates collagen in bone and contribute to decrease in bone strength. The mechanism of Hcy induced bone loss and remodeling is unclear. Therefore, the present study was aimed to determine the role of folic acid (FA) in genetically HHcy‐associated decrease in bone blood flow and remodeling. Wild type (WT) and cystathionine‐β‐synthase heterozygous (CBS+/−) mice were used in this study and supplemented with or without FA (300 mg/kg, Hcy reducing agent) in drinking water for 6 weeks. The tibial bone blood flow was measured by laser Doppler and ultrasonic flow probe method. The tibial bone density (BD) was assessed by dual energy X‐ray absorptiometry. The bone homogenates were analyzed for oxidative stress, NOX‐4 as oxidative marker and thioredoxin‐1 (Trx‐1) as anti‐oxidant marker, bone remodeling (MMP‐9) and bio‐availability of nitric oxide (eNOS/iNOS/NO) by Western blot method. The results suggested that there was decrease in tibial blood flow in CBS+/− mice. The BD was also reduced in CBS+/− mice. There was an increase in NOX‐4, iNOS, MMP‐9 protein as well as MMP‐9 activity in CBS+/− mice and decrease in Trx‐1, eNOS protein levels, in part by decreasing NO bio‐availability in CBS+/− mice. Interestingly, these effects were ameliorated by FA and suggested that FA supplementation may have therapeutic potential against genetically HHcy induced bone loss. © 2011 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 29: 1511–1516, 2011
Backbone‐Thermoresponsive Hyperbranched Polyglycerol by Random Copolymerization of Glycidol and 3‐Methyl‐3‐(hydroxymethyl)oxetane
Authors: Xia Yumin , Wang Yimin , Wang Yanping , Wang Dali , Deng Hongping , Zhuang Yuanyuan , Yan Deyue , Zhu Bangshang , Zhu Xinyuan 
Published: April 2011

AbstractThe hyperbranched polyglycerol analog, hyperbranched poly[glycerol‐co‐3‐methyl‐3‐(hydroxymethyl)oxetane] [HP(G‐co‐M)], was synthesized in one‐step by random copolymerization of glycidol and 3‐methyl‐3‐(hydroxymethyl)oxetane (MHO). The obtained polymer exhibited a thermoresponsive behavior in an aqueous solution, and the corresponding lower critical solution temperature (LCST) could be readily adjusted by changing the feed ratio of glycidol to MHO. The MTT assay against COS‐7 cells demonstrated that HP(G‐co‐M) had low cytotoxicity. Moreover, the existence of numerous hydroxyl terminals of HP(G‐co‐M) facilitated their further modification and functionalization. All of these characteristics suggest that this novel backbone‐thermoresponsive hyperbranched polyglycerol is a promising functional material for biomedical applications.
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Rapid UV Light‐Triggered Macromolecular Click Conjugations via the Use of o‐Quinodimethanes
Authors: Gruendling Till , Oehlenschlaeger Kim K. , Frick Elena , Glassner Mathias , Schmid Christina , Barner‐Kowollik Christopher 
Published: April 2011

AbstractShining a light on click chemistry: The use of UV‐radiation as trigger signal provides a facile means to obtain spatial and temporal control over polymer conjugation reactions in addition to providing a further means of achieving orthogonality in click transformations. In the current contribution, UV‐radiation was employed to induce a highly efficient Diels–Alder conjugation of polymeric building blocks via the photo‐induced in situ formation of highly reactive cis‐dienes from a 2‐methylbenzophenone precursor. magnified image
PREPARED: Comparison of prolonged and immediate release ropinirole in advanced Parkinson's disease
Authors: Stocchi Fabrizio , Giorgi Luigi , Hunter Brian , Schapira Anthony HV 
Published: April 2011

AbstractBackground: PREPARED was a randomized, parallel‐group, double‐blind, multicenter study to evaluate the efficacy of adjunctive ropinirole prolonged release (PR) versus immediate release (IR) in patients with advanced Parkinson's disease (PD). Methods: Patients received once‐daily PR (2–24 mg/d; n = 177) or three‐times‐daily IR (0.75–24 mg/d; n = 173) for 24 weeks. The primary endpoint was the proportion of patients maintaining ≥20% reduction from baseline in “off” time over two consecutive visits at Week 24 last observation carried forward (LOCF). Results: At Week 24 LOCF, PR significantly increased the proportion of patients maintaining ≥20% reduction in “off” time versus IR (adjusted odds ratio: 1.82; 95% CI: 1.16, 2.86; P = 0.009). Mean (SD) doses at Week 24 LOCF were: PR, 18.6 (6.5) mg/d; IR, 10.4 (6.4) mg/d; mean (SD) reductions from baseline in levodopa (L‐dopa) dose were –162 (226) mg and –113 (138) mg, respectively. Adverse events (AEs) were reported by 72% of patients in the PR group and 61% in the IR group; 12% and 9% of patients, respectively, withdrew from the study due to an AE, and 6% and 5%, respectively, reported serious AEs. Conclusions: Adjunctive PR provided a significantly greater improvement in symptom control in terms of the odds of achieving ≥20% maintained reduction in time spent “off” compared with IR. Interpretation may be confounded by the higher doses of PR versus IR that were achieved, in combination with lower doses of L‐dopa by the study end. Despite dosing differences, the PR titration regimen was generally well tolerated, with an AE profile similar to that of IR. © 2011 Movement Disorder Society
Comparison of subthalamic nucleus deep brain stimulation and Duodopa in the treatment of advanced Parkinson's disease
Authors: Merola Aristide , Zibetti Maurizio , Angrisano Serena , Rizzi Laura , Lanotte Michele , Lopiano Leonardo 
Published: April 2011

AbstractBackground:Subthalamic nucleus deep brain stimulation (STN‐DBS) and levodopa/carbidopa enteral (Duodopa) infusion are two effective therapeutic options for the treatment of advanced Parkinson's disease (PD).Methods:Retrospectively, this study compared the two procedures, evaluating 40 PD patients who underwent either STN‐DBS or a percutaneous gastrostomy (PEG) for Duodopa infusion. Duodopa group comprised 20 patients, with a mean follow‐up of ∼15 months, treated by Duodopa infusion rather than STN‐DBS because of the presence of neurosurgical contraindications, age > 70 years‐old, moderate cognitive impairment or patient's unwillingness to undergo neurosurgery. The STN‐DBS group comprised 20 consecutive patients similar to the patients of the Duodopa group for age at the disease onset, age at the procedure, follow‐up, and duration of motor complications. The only difference concerned neuropsychological functions, which were more impaired in the group of Duodopa patients. Clinical and neuropsychological data were compared at baseline and at follow‐up for the two procedures.Results:Both procedures showed a significant improvement in UPDRS‐II, UPDRS‐III, and UPDRS‐IV and a considerable reduction in the percentage of waking day spent in “off,” whereas only the STN‐DBS group showed a significant improvement in dyskinesias duration and disability. STN‐DBS was associated to a significant drop in the phonemic verbal fluency score, whereas Duodopa patients showed a milder worsening in this task. The procedure‐related complications occurred more frequently with Duodopa.Conclusion:STN‐DBS and Duodopa showed a significant efficacy on motor symptoms, activities of daily living, and motor complications. The group of Duodopa‐treated patients developed more procedure‐related complications. © 2011 Movement Disorder Society
Variants in estrogen‐related genes and risk of Parkinson's disease
Authors: Chung Sun Ju , Armasu Sebastian M. , Biernacka Joanna M. , Lesnick Timothy G. , Rider David N. , Cunningham Julie M. , Maraganore Demetrius M. 
Published: April 2011

AbstractIncidence rates of Parkinson's disease are higher in men than in women at all ages, and these differences may be a result of the neuroprotective effects of estrogen on the nigrostriatal pathway. We investigated the association of common variants in 4 estrogen‐related genes with Parkinson's disease. Tagging single‐nucleotide polymorphisms in the CYP19A1, ESR1, ESR2, and PRDM2 genes were selected from the International Haplotype Map and genotyped in 1103 Parkinson's disease cases from the upper Midwest of the United States and in 1103 individually matched controls (654 unaffected siblings, and 449 unrelated controls from the same region). Of 137 informative single‐nucleotide polymorphisms, 2 PRDM2 single‐nucleotide polymorphisms were significantly associated with an increased risk of Parkinson's disease at the Bonferroni‐corrected significance level of 0.0004 (rs2744690: OR, 1.54; SE(logOR), .109; 99.96% CI, 1.05–2.26; uncorrected P = .0001; rs2744687: OR, 1.53; SE(logOR), .113; 99.96% CI, 1.03–2.29, uncorrected P = .0002); the association was significant in the women‐only stratum but not in the men‐only stratum. An additional 6 single‐nucleotide polymorphisms in PRDM2, 2 in ESR1, 1 in ESR2, and 1 in CYP19A1 had significant P values in the overall sample before Bonferroni correction. None of the single‐nucleotide polymorphisms were significantly associated with age at onset of Parkinson's disease after Bonferroni correction. Our results confirm the association of PRDM2 variants with Parkinson's disease susceptibility, especially in women. © 2011 Movement Disorder Society
Atlas‐based automated positioning of outer volume suppression slices in short‐echo time 3D MR spectroscopic imaging of the human brain
Authors: Yung Kaung‐Ti , Zheng Weili , Zhao Chenguang , Martínez‐Ramón Manel , van der Kouwe André , Posse Stefan 
Published: April 2011

AbstractSpatial suppression of peripheral lipid‐containing regions in volumetric MR spectroscopic imaging of the human brain requires placing large numbers of outer volume suppression (OVS) slices, which is time‐consuming, prone to operator error and may introduce subject‐dependent variability in volume coverage. We developed a novel, computationally efficient atlas‐based approach for automated positioning of up to 16 OVS slices and the MR spectroscopic imaging slab. Standardized positions in Montreal Neurological Institute atlas space were established offline using a recently developed iterative optimization procedure. During the scanning session, positions in subject space were computed using affine transformation of standardized positions in Montreal Neurological Institute space. Offline analysis using magnetization prepared rapid gradient echo scans from 11 subjects demonstrated reliable OVS placement, comparable with but faster than iterative placement in subject space. This atlas‐based method was further validated in 14 subjects using 3D short‐echo time proton‐echo‐planar‐spectroscopic‐imaging at 3 T. Comparison of manual and automatic placement using 8 OVS slices demonstrated consistent MR spectroscopic imaging volume selection and comparable spectral quality with similar degree of lipid suppression and number of usable voxels. Automated positioning of 16 OVS slices enabled larger volume coverage, while maintaining similar spectral quality and lipid suppression. Atlas‐based automatic prescription of short echo time MR spectroscopic imaging is expected to be advantageous for longitudinal and cross‐sectional studies. Magn Reson Med, 2011. © 2011 Wiley‐Liss, Inc.
Influence of the ortho effect in the solvolyses of dichlorobenzoyl chlorides
Authors: Park Kyoung‐Ho , Kevill Dennis N. 
Published: April 2011

AbstractThe ortho‐effect of substituents upon the kinetics of reactions taking place at a reaction center attached to an aromatic ring has long been a topic of interest. For benzoyl chloride solvolyses, it was shown by Bentley and coworkers that the 2,6‐dimethyl‐derivative followed an ionization pathway with characteristics very similar to those for the solvolyses of p‐methoxybenzoyl chloride. We have carried out a Grunwald–Winstein equation treatment of the solvolyses of 2,6‐dichlorobenzoyl chloride, with similar sized chlorines replacing the methyl groups but now with an overall electron‐withdrawing influence of the ortho‐substituents. In this way the reactivity is moderated and the study can be extended to the important fluoroalcohol‐containing solvents. For the 30 solvents studied, an ionization pathway with a moderate nucleophilic solvation component is indicated. For comparison purposes, the treatment has also been applied to the 2,4‐, 3,4‐, and 3,5‐dichloro‐ derivatives. For the 2,4‐dichloro‐derivative, the two reaction channels are clearly visible and the solvents included for each channel are consistent with their solvent properties. Copyright © 2011 John Wiley & Sons, Ltd.
The role of tyrosine 71 in modulating the flap conformations of BACE1
Authors: Spronk Steven A. , Carlson Heather A. 
Published: April 2011

Abstractβ‐site amyloid precursor protein cleaving enzyme 1 (BACE1) is a potential target for treating Alzheimer's disease. BACE1's binding site is partially covered by a flexible loop on its N‐terminal domain, known as the “flap,” which has been found in several conformations in crystal structures of BACE1 and other aspartyl proteases. The side chain of the invariant residue Tyr71 on the flap adopts several rotameric orientations, leading to our hypothesis that the orientation of this residue dictates the movement and conformations available to the flap. We investigated this hypothesis by performing 220 ns of molecular dynamics simulations of bound and unbound wild‐type BACE1 as well as the unbound Y71A mutant. Our findings indicate that the flap exhibits various degrees of mobility and adopts different conformations depending on the Tyr71 orientation. Surprisingly, the “self‐inhibited” form is stable in our simulations, making it a reasonable target for drug design. The alanine mutant, lacking a large side chain at position 71, displays significant differences in flap dynamics from wild type, freely sampling very open and closed conformations. Our simulations show that Tyr71, in addition to its previously determined functions in catalysis and substrate binding, has the important role of modulating flap conformations in BACE1. Proteins 2011; © 2011 Wiley‐Liss, Inc.
Modelling of multijunction solar cells with dilute nitride n–i–p–i junctions
Authors: Royall B. , Balkan N. 
Published: April 2011

AbstractWe are proposing a novel structure containing GaInNAs n–i–p–i layers with a band gap of 1 eV connected in series to a GaInP/GaAs tandem structure. The device performance is modelled using the drift diffusion conductivity model where the number and thickness of the layers are taken as adjustable parameters to achieve the optimum design. We obtain the value of short‐circuit current to keep the n–i–p–i cell current matched to the other junctions in the tandem structure.
Changes in the responsiveness of serum leptin and hypothalamic neuropeptide Y mRNA levels to food deprivation in developing rats
Authors: Iwasa Takeshi , Matsuzaki Toshiya , Kinouchi Riyo , Gereltsetseg Ganbat , Murakami Masahiro , Nakazawa Hiroshi , Yasui Toshiyuki , Irahara Minoru 
Published: April 2011

AbstractNeuropeptide Y (NPY) is an important orexigenic peptide that acts in the brain. The increase in hypothalamic NPY mRNA expression induced by fasting is mainly caused by a decrease in the effects of leptin. We investigated the developmental changes in the sensitivities of leptin and hypothalamic neuropeptide Y to fasting. Hypothalamic NPY mRNA levels were increased by fasting in postnatal days 15 and 25 rats, but not in postnatal day 5 rats. Serum leptin levels were decreased by fasting in rats at all ages (days 5, 15, and 25). In addition, hypothalamic OB‐Rb mRNA levels were decreased by fasting in postnatal day 25 rats, but not in postnatal day 5 or 15 rats. Although the percentage of fating‐induced decrease in the serum leptin level was larger in the postnatal day 15 rats than in the postnatal day 25 rats, the percentage of increase in the hypothalamic NPY mRNA level in the postnatal day 15 rats was smaller than that in the postnatal day 25 rats. There was a strong inverse correlation between serum leptin levels and hypothalamic NPY mRNA levels in the postnatal day 25 rats, whereas no significant correlation was found between these parameters in the postnatal day 5 or 15 rats. These findings indicate that the sensitivity of hypothalamic NPY mRNA expression to food deprivation and hypoleptinemia has developed by postnatal day 25.
THE QUASILINEARITY OF SOME FUNCTIONALS ASSOCIATED WITH THE RIEMANN–STIELTJES INTEGRAL
Authors: DRAGOMIR S. S. , FEDOTOV I. 
Published: April 2011

AbstractThe superadditivity and subadditivity of some functionals associated with the Riemann–Stieltjes integral are established. Applications in connection to Ostrowski’s and the generalized trapezoidal inequalities and for special means are provided.