bluuebunny/crossref_metadata_2025_split huggingface dataset:
Bioactive glass and autogenous bone as bone graft substitutes in benign bone tumors
Authors: Lindfors Nina C. , Heikkilä Jouni T. , Koski Ilona , Mattila Kimmo , Aho Allan J. 
Published: November 2008

AbstractIn a prospective randomized study, 25 patients with benign bone tumors were surgically treated with either bioactive glass S53P4 (BG) or autogenous bone (AB) as bone graft material. X‐rays were taken preoperatively and postoperatively at 2 weeks and at 3, 8, 12, 18, 24, and 36 months. In addition, for most of the patients, CT scans were performed at the same time‐points. No infections or material‐related adverse reactions occurred in any patient. The filled cavity was replaced faster by new bone in the AB group than in the BG group (p = 0.0001). However, at 36 months, no statistical difference in cavity volume between the two groups was observed on X‐rays (p = 0.7881) or on CT scans (p = 0.9117). In the BG group at 3 years, the filled cavity appeared, however, dense on X‐rays, and glass granules on CT scans were observed. During the follow‐up period, the cortical thickness seemed to increase more in the BG group than in the AB group (p < 0.0001). © 2008 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2009
Conformational preferences of N‐methoxycarbonyl proline dipeptide
Authors: Kang Young Kee , Kang Nam Sook 
Published: November 2008

AbstractThe conformational study on N‐methoxycarbonyl‐L‐proline‐N′‐methylamide (Moc‐Pro‐NHMe, prolylcarbamate) is carried out using ab initio HF and density functional B3LYP methods with the self‐consistent reaction field method in the gas phase and in solution (chloroform, acetonitrile, and water). The replacement of the N‐acetyl group by the N‐methoxycarbonyl group results in the changes in conformational preferences, populations for backbone and prolyl puckering, and barriers to cis‐trans isomerization of the prolyl residue in the gas phase and in solution, although there are small changes in the geometry of the prolyl peptide bond and the torsion angles of backbone and prolyl ring. The cis population increases with the increase of solvent polarity, as found for Ac‐Pro‐NHMe (prolylamide), but it is amplified by 9% in the gas phase and about 17% in solution for prolylcarbamate compared with those for prolylamide. It is found that the cis‐trans isomerization for prolylcarbamate proceeds through the clockwise rotation with ω′ ≈ +120° about the prolyl peptide bond in the gas phase and in solution, as found for prolylamide. However, the rotational barriers to the cis‐trans isomerization for prolylcarbamate are calculated to be 3.7–4.7 kcal/mol lower than those of prolylamide in the gas phase and in solution, and are found to be less sensitive to the solvent polarity. The calculated rotational barriers for prolylcarbamate in chloroform and water are in good agreement with the observed values. The shorter hydrogen‐bond distance between the prolyl nitrogen and the amide H (HNHMe) of the NHMe group, the decrease in electron overlap of the prolyl CN bond, and the favorable electrostatic interaction between the ester oxygen and the amide HNHMe for the transition state seem to play a role in lowering the rotational barrier of prolylcarbamate. The smaller molecular dipole moments of the ground‐ and transition‐state structures for prolylcarbamate in the gas phase and in solution seem to be one of factors to make the rotational barrier less sensitive to the solvent polarity. As the solvent polarity increases (i.e., from the gas phase to chloroform to acetonitrile), the value of ΔH decreases and the magnitude of ΔS increases for prolylcarbamate, which results in a nearly constant value of the rotational barrier. © 2008 Wiley Periodicals, Inc. J Comput Chem, 2009
Ab initio description of photoabsorption and electron transfer in a doubly‐linked porphyrin‐fullerene dyad
Authors: Cramariuc Oana , Hukka Terttu I. , Rantala Tapio T. , Lemmetyinen Helge 
Published: November 2008

AbstractStructure, photoabsorption and excited states of two representative conformations obtained from molecular dynamics (MD) simulations of a doubly‐linked porphyrin‐fullerene dyad DHD6ee are studied by using both DFT and wavefunction based methods. Charge transfer from the donor (porphyrin) to the acceptor (fullerene) and the relaxation of the excited state are of special interest. The results obtained with LDA, GGA, and hybrid functionals (SVWN, PBE, and B3LYP, respectively) are analyzed with emphasis on the performance of used functionals as well as from the point of view of their comparison with wavefunction based methods (CCS, CIS(D), and CC2). Characteristics of the MD structures are retained in DFT optimization. The relative orientation of porphyrin and fullerene is significantly influencing the MO energies, the charge transfer (CT) in the ground state of the dyad and the excitation of ground state CT complex (g‐CTC). At the same time, the excitation to the locally excited state of porphyrin is only little influenced by the orientation or cc distance. TD‐DFT underestimates the excitation energy of the CT state, however for some cases (with relatively short donor‐acceptor separations), the use of a hybrid functional like B3LYP alleviates the problem. Wavefunction based methods and CC2 in particular appear to overestimate the CT excitation energies but the inclusion of proper solvation models can significantly improve the results. © 2008 Wiley Periodicals, Inc. J Comput Chem, 2009
Topology‐based models and NMR structures in protein folding simulations
Authors: Rey‐Stolle M. Fernanda , Enciso Marta , Rey Antonio 
Published: November 2008

AbstractTopology‐based interaction potentials are simplified models that use the native contacts in the folded structure of a protein to define an energetically unfrustrated folding funnel. They have been widely used to analyze the folding transition and pathways of different proteins through computer simulations. Obviously, they need a reliable, experimentally determined folded structure to define the model interactions. In structures elucidated through NMR spectroscopy, a complex treatment of the raw experimental data usually provides a series of models, a set of different conformations compatible with the available experimental data. Here, we use an efficient coarse‐grained simulation technique to independently consider the contact maps from every different NMR model in a protein whose structure has been resolved by the use of NMR spectroscopy. For λ‐Cro repressor, a homodimeric protein, we have analyzed its folding characteristics with a topology‐based model. We have focused on the competition between the folding of the individual chains and their binding to form the final quaternary structure. From 20 different NMR models, we find a predominant three‐state folding behavior, in agreement with experimental data on the folding pathway for this protein. Individual NMR models, however, show distinct characteristics, which are analyzed both at the level of the interplay between tertiary/quaternary structure formation and also regarding the thermal stability of the tertiary structure of every individual chain. © 2008 Wiley Periodicals, Inc. J Comput Chem, 2009
Investigations of an OH · · · S hydrogen bond via Car‐Parrinello and path integral molecular dynamics
Authors: Jezierska Aneta , Panek Jarosław J. 
Published: November 2008

AbstractThe presence of intramolecular hydrogen bonds influences the binding energy, tautomeric equilibrium, and spectroscopic properties of various classes of organic molecules. This article discusses the OH · · · S bridge, one of the less commonly investigated types of intramolecular interactions. 3‐mercapto‐1,3‐diphenylprop‐2‐en‐1‐one was considered as the model structure. This compound exhibits photochromic properties. Car‐Parrinello molecular dynamics (CPMD) was applied to investigate the spectroscopic and molecular properties of this compound in the gas phase and in the solid state. The second part of the study is devoted to the effects of the quantization of nuclear motions, with special attention to the OH · · · S moiety. Path integral molecular dynamics (PIMD) of the molecular crystal of 3‐mercapto‐1,3‐diphenylprop‐2‐en‐1‐one was carried out for this purpose. The employment of this fully quantum mechanical technique enables one to study, in a time‐averaged sense, the zero‐point motion important for flat potential energy surfaces. Finally, the potentials of mean force (Pmfs) were calculated from the CPMD and PIMD data obtained for the solid‐state calculations. The effect of including quantum nuclear motion was investigated. In the studied compound, quantum effects shortened the H‐bridge and provided a better description of the free energy minimum. The computational results place this uncommon intramolecular H‐bonding among the class of strong hydrogen bonds with large red shifts of OH stretching modes, which correspond well with previously presented experimental data in the literature concerning this structure. © 2008 Wiley Periodicals, Inc. J Comput Chem, 2009
Metastasis and AKT activation
Authors: Sheng Shijie , Qiao Meng , Pardee Arthur B. 
Published: November 2008

AbstractMetastasis, responsible for 90% of cancer patient deaths, is an inefficient process because many tumor cells die. The survival of metastatic tumor cells should be considered as a critical therapeutic target. This review provides a new perspective regarding the role of AKT in tumor survival, and the rationale to target AKT in anti‐metastasis therapies. J. Cell. Physiol. 218: 451–454, 2009. © 2008 Wiley‐Liss, Inc.
Glycosaminoglycan composition changes with MG‐63 osteosarcoma osteogenesis in vitro and induces human mesenchymal stem cell aggregation
Authors: Kumarasuriyar A. , Murali S. , Nurcombe V. , Cool S.M. 
Published: November 2008

AbstractOsteogenic differentiation is coordinated by the exposure of cells to temporal changes in a combination of growth factors and elements within the extracellular matrix (ECM). Many of the key proteins that drive these changes share the property of being dependent on ECM glycosaminoglycans (GAGs) for their activity. Here, we examined whether GAGs isolated from proliferating, differentiating and mineralizing MG‐63 osteosarcoma cells differed in their physical properties, and thus in their capacities to coordinate the osteogenic cascade both in human MG‐63 osteosarcoma cells and primary human mesenchymal stem cells (hMSCs). Our results show that the size distribution of GAGs, the expression of GAG‐carrying proteoglycan cores and the expression of enzymes involved in their modification systematically change as MG‐63 cells mature in culture. When dosed back onto cells exogenously in soluble form, GAGs regulated MG‐63 survival and growth in a dose‐dependent manner, but not differentiation in either cell type. In contrast, hMSCs aggregated into distinct colonies when grown on GAG‐coated substrates, while MG‐63 cells did not. Heparin‐coated substrates improved hMSC viability without inducing aggregation. These results suggest a complex role for GAGs in coordinating the emergence of the osteoblast phenotype, and provide further evidence for the use of heparans in bone tissue repair applications. J. Cell. Physiol. 218: 501–511, 2009. © 2008 Wiley‐Liss, Inc.
Evidence that leptin through STAT and CREB signaling enhances cyclin D1 expression and promotes human endometrial cancer proliferation
Authors: Catalano Stefania , Giordano Cinzia , Rizza Pietro , Gu Guowei , Barone Ines , Bonofiglio Daniela , Giordano Francesca , Malivindi Rocco , Gaccione Donatella , Lanzino Marilena , De Amicis Francesca , Andò Sebastiano 
Published: November 2008

AbstractObesity is a risk factor for endometrial cancer in pre‐ and post‐menopausal women. Leptin, an adipocyte‐derived hormone, in addition to the control weight homeostasis, is implicated in multiple biological actions. A recent study demonstrated that leptin promotes endometrial cancer growth and invasiveness through STAT/MAPK and Akt pathways, but the molecular mechanism involved in such processes still needs to be elucidated. In an attempt to understand the role of leptin in regulating endometrial cancer cells proliferation, we have demonstrated that leptin treatment reduced the numbers of cells in G0/G1‐phase while increased cell population in S‐phase. This effect is associated with an up‐regulation of cyclin D1 together with a down‐regulation of cyclin‐dependent kinase inhibitor p21WAF1/Cip1. Mutagenesis studies, eletrophoretic mobility shift, and chromatin immunoprecipitation analysis revealed that signal transducers and activators of transcription 3 (STAT3) and cyclic AMP‐responsive element (CRE) binding protein motifs, within cyclin D1 promoter, were required for leptin‐induced cyclin D1 expression in Ishikawa endometrial cancer cells. Silencing of STAT3 and CREB gene expression by RNA interference reversed the up‐regulatory effect of leptin on cyclin D1 expression and cells proliferation. These results support the hypothesis that STAT3 and CREB play an important role in leptin signaling pathway that leads to the proliferation of Ishikawa cells, thus establishing a direct association between obesity and endometrial tumorogenesis. J. Cell. Physiol. 218: 490–500, 2009. © 2008 Wiley‐Liss, Inc.
Analysis of gene expression in gecko digital adhesive pads indicates significant production of cysteine‐ and glycine‐rich beta‐keratins
Authors: Hallahan David L. , Keiper‐Hrynko Natalie M. , Shang Tanya Q. , Ganzke Thaya S. , Toni Mattia , Dalla Valle Luisa , Alibardi Lorenzo 
Published: November 2008

AbstractMicroscopic bristles (setae) present on digital pads permit the adhesion and climbing of geckos. Keratins of setae of the lizard Gekko gecko (Tokay gecko) were analyzed by the isolation of expressed mRNAs and by the generation of an EST library. Of the 510 sequences determined, 268 (52.9%) were unique. Of these, 14 appeared to encode alpha‐ and 111 beta‐keratins. Within the beta‐keratins, we identified five groups based on nucleotide sequence comparisons. Of these, one contained the bulk of beta‐keratins, with 103 EST members. The mRNAs within this major group, together with two singlets, encoded cysteine–proline–serine‐rich proteins of 10–14 kDa (Ge‐cprp). One of the smaller groups of transcripts encoded slightly larger glycine–proline–serine‐rich proteins, of 14–19 kDa (Ge‐gprp). The remaining group consisted of smaller (9 kDa) serine–tyrosine‐rich beta‐keratins (Ge‐strp). Thus three classes could be distinguished by amino acid sequence alignment. Exact matches for some of the peptide sequences obtained from setal proteins by ms/ms sequencing occur within several of these clones. Most of the beta‐keratins were basic and contained a core‐box region of two beta‐strand sequences, with high homology to core‐boxes present in avian scale and feather beta‐keratins. Core‐boxes are beta‐folded regions that are likely responsible for polymerization into the beta‐keratin filaments. The two deduced alpha‐keratins of 52.7 kDa are both acidic, and contain the typical central rod region with some homology to mammalian and avian alpha‐keratins, with variable N‐ and C‐terminal regions. Basic beta‐keratins and acidic alpha‐keratins may interact electrostatically to form the resistant corneous material of setae. J. Exp. Zool. (Mol. Dev. Evol.) 312B:58–73, 2009. © 2008 Wiley‐Liss, Inc.
Remodeling of fracture callus in mice is consistent with mechanical loading and bone remodeling theory
Authors: Isaksson Hanna , Gröngröft Ina , Wilson Wouter , van Donkelaar Corrinus C. , van Rietbergen Bert , Tami Andrea , Huiskes Rik , Ito Keita 
Published: November 2008

AbstractDuring the remodeling phase of fracture healing in mice, the callus gradually transforms into a double cortex, which thereafter merges into one cortex. In large animals, a double cortex normally does not form. We investigated whether these patterns of remodeling of the fracture callus in mice can be explained by mechanical loading. Morphologies of fractures after 21, 28, and 42 days of healing were determined from an in vivo mid‐diaphyseal femoral osteotomy healing experiment in mice. Bone density distributions from microCT at 21 days were converted into adaptive finite element models. To assess the effect of loading mode on bone remodeling, a well‐established remodeling algorithm was used to examine the effect of axial force or bending moment on bone structure. All simulations predicted that under axial loading, the callus remodeled to form a single cortex. When a bending moment was applied, dual concentric cortices developed in all simulations, corresponding well to the progression of remodeling observed experimentally and resulting in quantitatively comparable callus areas of woven and lamellar bone. Effects of biological differences between species or other reasons cannot be excluded, but this study demonstrates how a difference in loading mode could explain the differences between the remodeling phase in small rodents and larger mammals. © 2008 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 27: 664–672, 2009
Using real‐time MRI to quantify altered joint kinematics in subjects with patellofemoral pain and to evaluate the effects of a patellar brace or sleeve on joint motion
Authors: Draper Christine E. , Besier Thor F. , Santos Juan M. , Jennings Fabio , Fredericson Michael , Gold Garry E. , Beaupre Gary S. , Delp Scott L. 
Published: November 2008

AbstractAbnormal patellofemoral joint motion is a possible cause of patellofemoral pain, and patellar braces are thought to alleviate pain by restoring normal joint kinematics. We evaluated whether females with patellofemoral pain exhibit abnormal patellofemoral joint kinematics during dynamic, weight‐bearing knee extension and assessed the effects of knee braces on patellofemoral motion. Real‐time magnetic resonance (MR) images of the patellofemoral joints of 36 female volunteers (13 pain‐free controls, 23 patellofemoral pain) were acquired during weight‐bearing knee extension. Pain subjects were also imaged while wearing a patellar‐stabilizing brace and a patellar sleeve. We measured axial‐plane kinematics from the images. Females with patellofemoral pain exhibited increased lateral translation of the patella for knee flexion angles between 0°and 50° (p = 0.03), and increased lateral tilt for knee flexion angles between 0° and 20° (p = 0.04). The brace and sleeve reduced the lateral translation of the patella; however, the brace reduced lateral displacement more than the sleeve (p = 0.006). The brace reduced patellar tilt near full extension (p = 0.001), while the sleeve had no effect on patellar tilt. Our results indicate that some subjects with patellofemoral pain exhibit abnormal weight‐bearing joint kinematics and that braces may be effective in reducing patellar maltracking in these subjects. Published by Wiley Periodicals, Inc. J Orthop Res 27: 571–577, 2009
Effect of cocoa butter replacement with a β‐glucan‐rich hydrocolloid (C‐trim30) on the rheological and tribological properties of chocolates
Authors: Lee Suyong , Biresaw Girma , Kinney Mary P. , Inglett George E. 
Published: November 2008

AbstractBACKGROUND: The food industry has been facing the challenge of developing low‐fat and low‐calorie food products due to rising health awareness of consumers. To meet this consumer demand, an oat β‐glucan‐rich hydrocolloid (C‐trim30) was evaluated as a cocoa butter substitute in chocolates. The effects of C‐trim30 on the rheological, tribological, and textural properties of chocolates were investigated.RESULTS: The viscosity of molten chocolates increased with increasing levels of C‐trim30. Flow behaviors analyzed using the Casson model showed that the Casson viscosity and yield stress increased with increasing concentration of C‐trim30 in the chocolate. Tribological tests on a ball‐on‐flat tribometer showed a reduction in boundary coefficients of friction, with increasing C‐trim30. In addition, hardness of chocolates showed that replacement of cocoa butter with C‐trim30 produced chocolates with softer texture.CONCLUSIONS: The cocoa butter replacement with C‐trim30 up to 10% produced soft chocolates with improved boundary lubrication properties. Also, the chocolate prepared by replacing the cocoa butter with C‐trim30 resulted in a product with a lower caloric value and increased health benefits from the oat β‐glucan. Copyright © 2008 Society of Chemical Industry
Tensile and moisture barrier properties of whey protein–beeswax layered composite films
Authors: Min Sea C , Janjarasskul Theeranun , Krochta John M 
Published: November 2008

AbstractBACKGROUND: There is a lack of research on producing layered protein–lipid composite films with improved tensile and barrier properties compared to films from individual components. Several film‐forming parameters were hypothesized to influence the extent to which lipids were either dispersed within or layered upon whey protein films. Film‐forming parameters investigated were ratio of whey protein isolate (WPI) to beeswax (BW), homogenization method, sodium chloride (NaCl) concentration, and BW particle size.RESULTS: Film percent elongation (E) increased, while tensile strength (TS) and elastic modulus (EM) decreased when BW was incorporated into WPI films, demonstrating a lubricant effect of the BW. Mean water vapor permeability values for WPI film decreased by 57% when the film composition was modified by the addition of 40% BW. BW phase separation was observed in all of the tested films. Particle size of BW in the film‐forming emulsions was larger in the presence of NaCl (100 mmol L−1), indicating a neutralization of particle charge. However, the addition of NaCl did not improve the moisture barrier of WPI‐BW film over the range of film‐forming conditions used in the study.CONCLUSION: The results from this study are useful in determining formulations and conditions for the production of composite films from WPI and BW with improved tensile and moisture barrier properties. Copyright © 2008 Society of Chemical Industry
Evaluating the nutritive values and in vitro degradability characteristics of leaves, seeds and seedpods from Moringa stenopetala
Authors: Melesse Aberra , Bulang Michael , Kluth Holger 
Published: November 2008

AbstractBACKGROUND: Moringa stenopetala is a multipurpose tree which has several agricultural, industrial and medicinal uses. The nutritive value of East African M. stenopetala has not been fully investigated and pertinent data for ruminants are lacking. The present study was therefore conducted to fill this gap by providing the latest information on chemical composition and in vitro fermentation of M. stenopetala tree parts.RESULTS: The respective metabolizable energy values for leaves, seeds and seedpods were 10.0, 7.0 and 5.1 g kg−1 dry matter (DM). The crude protein (CP) contents for leaves, seeds and seedpods were 395, 282 and 110 g kg−1 DM, respectively. For leaves and seeds, 88% and 83%, respectively, of the CP was true protein. Fat contents (g kg−1 DM) were relatively high in seeds (334) but not in leaves (84) or seedpods (110). No starch was detected in seeds. Leaves were a potentially useful source of calcium,, sodium and manganese, containing 18.5, 4.1 and 0.086 g kg−1 DM, respectively. The concentrations of essential amino acids in leaves for leucine, valine, phenylalanine, isoleucine and threonine were 8.5, 5.3, 5.3, 4.5, and 4.4 g 16 g N−1, respectively, and were comparable to those found in soybean and Moringa olifera leaves. The contents of total phenols in seeds and leaves were 1.2 and 56.7 g kg−1 DM, respectively.CONCLUSION: The chemical composition of leaves and seeds from M. stenopetala revealed its potential as a protein and energy supplement for ruminant livestock. Copyright © 2008 Society of Chemical Industry