bluuebunny/crossref_metadata_2025_split huggingface dataset:
Computed Microtomography of Bone Specimens for Rapid Analysis of Bone Changes Associated With Malignancy
Authors: Chappard Daniel , Libouban Hélène , Legrand Erick , Ifrah Norbert , Masson Charles , Baslé Michel Felix , Audran Maurice 
Published: April 2010

AbstractBreast and prostate cancers are specially metastasizing to bone. Metastases from breast cancer usually exhibit a mixed osteolytic/osteosclerotic aspect, with osteolysis predominating. Osteosclerosis is a common finding in prostatic cancer although osteolysis occurs within the sclerotic lesions. B‐cell malignancies (lymphoma, myeloma) are also associated with marked osteolysis. Histopathological examination of bone biopsies was used for the diagnosis of malignancies and, prior to embedding, microcomputed tomography (microCT) was done on the bone specimens. Patients (247) who presented either a bone metastasis, an overt myeloma, a lymphoma or a monoclonal gammopathy of undetermined significance were studied. All patients had a bone biopsy studied by 2D histomorphometry for the histopathology. During the fixation time, the bone cores were analyzed by microCT. On the 3D reconstructed models provided by microCT, signs of osteolysis/osteosclerosis were searched: excess of bone resorption, focal disorganization of microarchitecture, bone metaplasia, osteosclerosis. A strong agreement was obtained between histomorphometry and microCT results using Cohen's kappa test (κ = 0.713). MicroCT identified excess bone resorption on trabecular surfaces when eroded surfaces were >10.5% by histomorphometry. MicroCT failed to identify some patients with smoldering myeloma or some lymphomas with microresorption. MicroCT data are obtained within 4 hr and suggest the malignant invasion of bone marrow when excess of bone resorption/formation is obtained. MicroCT can be used in the immediate postbiopsy period making possible a fast identification of malignancy. However these signs are not specific and must be confirmed by histopathological analysis. Anat Rec 293:1125–1133, 2010. © 2010 Wiley‐Liss, Inc.
Matrix metalloproteinase 13 loss associated with impaired extracellular matrix remodeling disrupts chondrocyte differentiation by concerted effects on multiple regulatory factors
Authors: Borzí Rosa Maria , Olivotto Eleonora , Pagani Stefania , Vitellozzi Roberta , Neri Simona , Battistelli Michela , Falcieri Elisabetta , Facchini Annalisa , Flamigni Flavio , Penzo Marianna , Platano Daniela , Santi Spartaco , Facchini Andrea , Marcu Kenneth B. 
Published: April 2010

AbstractObjectiveTo link matrix metalloproteinase 13 (MMP‐13) activity and extracellular matrix (ECM) remodeling to alterations in regulatory factors leading to a disruption in chondrocyte homeostasis.MethodsMMP‐13 expression was ablated in primary human chondrocytes by stable retrotransduction of short hairpin RNA. The effects of MMP‐13 knockdown on key regulators of chondrocyte differentiation (SOX9, runt‐related transcription factor 2 [RUNX‐2], and β‐catenin) and angiogenesis (vascular endothelial growth factor [VEGF]) were scored at the protein level (by immunohistochemical or Western blot analysis) and RNA level (by real‐time polymerase chain reaction) in high‐density monolayer and micromass cultures under mineralizing conditions. Effects on cellular viability in conjunction with chondrocyte progression toward a hypertrophic‐like state were assessed in micromass cultures. Alterations in SOX9 subcellular distribution were assessed using confocal microscopy in micromass cultures and also in osteoarthritic cartilage.ResultsDifferentiation of control chondrocyte micromasses progressed up to a terminal phase, with calcium deposition in conjunction with reduced cell viability and scant ECM. MMP‐13 knockdown impaired ECM remodeling and suppressed differentiation in conjunction with reduced levels of RUNX‐2, β‐catenin, and VEGF. MMP‐13 levels in vitro and ECM remodeling in vitro and in vivo were linked to changes in SOX9 subcellular localization. SOX9 was largely excluded from the nuclei of chondrocytes with MMP‐13–remodeled or –degraded ECM, and exhibited an intranuclear staining pattern in chondrocytes with impaired MMP‐13 activity in vitro or with more intact ECM in vivo.ConclusionMMP‐13 loss leads to a breakdown in primary human articular chondrocyte differentiation by altering the expression of multiple regulatory factors.
Statistical validation of a global model for the distribution of the ultimate number of citations accrued by papers published in a scientific journal
Authors: Stringer Michael J. , Sales‐Pardo Marta , Amaral Luís A. Nunes 
Published: April 2010

AbstractA central issue in evaluative bibliometrics is the characterization of the citation distribution of papers in the scientific literature. Here, we perform a large‐scale empirical analysis of journals from every field in Thomson Reuters' Web of Science database. We find that only 30 of the 2,184 journals have citation distributions that are inconsistent with a discrete lognormal distribution at the rejection threshold that controls the false discovery rate at 0.05. We find that large, multidisciplinary journals are over‐represented in this set of 30 journals, leading us to conclude that, within a discipline, citation distributions are lognormal. Our results strongly suggest that the discrete lognormal distribution is a globally accurate model for the distribution of “eventual impact” of scientific papers published in single‐discipline journal in a single year that is removed sufficiently from the present date.
Scaffold stiffness affects the contractile function of three‐dimensional engineered cardiac constructs
Authors: Marsano Anna , Maidhof Robert , Wan Leo Q. , Wang Yadong , Gao Jin , Tandon Nina , Vunjak‐Novakovic Gordana 
Published: April 2010

AbstractWe investigated the effects of the initial stiffness of a three‐dimensional elastomer scaffold—highly porous poly(glycerol sebacate)—on functional assembly of cardiomyocytes cultured with perfusion for 8 days. The polymer elasticity varied with the extent of polymer cross‐links, resulting in three different stiffness groups, with compressive modulus of 2.35 ± 0.03 (low), 5.28 ± 0.36 (medium), and 5.99 ± 0.40 (high) kPa. Laminin coating improved the efficiency of cell seeding (from 59 ± 15 to 90 ± 21%), resulting in markedly increased final cell density, construct contractility, and matrix deposition, likely because of enhanced cell interaction and spreading on scaffold surfaces. Compact tissue was formed in the low and medium stiffness groups, but not in the high stiffness group. In particular, the low stiffness group exhibited the greatest contraction amplitude in response to electric field pacing, and had the highest compressive modulus at the end of culture. A mathematical model was developed to establish a correlation between the contractile amplitude and the cell distribution within the scaffold. Taken together, our findings suggest that the contractile function of engineered cardiac constructs positively correlates with low compressive stiffness of the scaffold. © 2010 American Institute of Chemical Engineers Biotechnol. Prog., 2010
Development of Amino–Oxazoline and Amino–Thiazoline Organic Catalysts for the Ring‐Opening Polymerisation of Lactide
Authors: Becker Jan M. , Tempelaar Sarah , Stanford Matthew J. , Pounder Ryan J. , Covington James A. , Dove Andrew P. 
Published: April 2010

AbstractThe ring‐opening polymerisation of lactide by a range of amino–oxazoline and amino–thiazoline catalysts is reported. The more electron‐rich derivatives are demonstrated to be the most highly active and polymerisation is well controlled, as evidenced by the linear relationship between the molecular weight and both the monomer conversion and the monomer‐to‐initiator ratio. Mechanistic studies reveal significant interactions between the monomer, initiator and catalyst and that the polymerisation is first order with respect to each of these components. These observations indicate that the polymerisation operates by a general base/pseudo‐anionic mechanism.
MnOx Nanoparticles Supported on a New Mesostructured Silicate with Textural Porosity
Authors: Tušar Nataša Novak , Ristić Alenka , Mali Gregor , Mazaj Matjaž , Arčon Iztok , Arčon Denis , Kaučič Venčeslav , Logar Nataša Zabukovec 
Published: April 2010

AbstractA two‐step synthesis of a novel mesostructured silicate, KIL‐2, and its manganese‐containing analogue, Mn/KIL‐2, has been developed. KIL‐2 possesses interparticle mesopores with pore dimensions between 5 and 60 nm and a surface area of 448 m2. The mesopores are formed by the aggregation of silica nanoparticles, which creates a network with interparticle voids. The particle size and the pore diameters depend on the temperature of the ageing step (first step) and on the solvothermal treatment in ethanol (second step), respectively. Mn/KIL‐2 contains octahedrally coordinated Mn3+ (80 %) and tetrahedrally coordinated Mn2+ (20 %) ions. Mn3+ ions are present in the extra‐framework MnOx nanoparticles with typical dimensions of 2 nm, which are homogeneously distributed throughout the material. Mn2+ ions occur as isolated manganese framework sites. The material is also able to retain its structure characteristics after the hydrothermal treatment in boiling water. Because of its non‐toxic nature and cost‐effective synthesis, Mn/KIL‐2 thus exhibits properties that are needed for an environment‐friendly catalyst.
Facile and Controllable Synthesis of Monodisperse CaF2 and CaF2:Ce3+/Tb3+ Hollow Spheres as Efficient Luminescent Materials and Smart Drug Carriers
Authors: Zhang Cuimiao , Li Chunxia , Peng Chong , Chai Ruitao , Huang Shanshan , Yang Dongmei , Cheng Ziyong , Lin Jun 
Published: April 2010

AbstractHighly uniform and well‐dispersed CaF2 hollow spheres with tunable particle size (300–930 nm) have been synthesized by a facile hydrothermal process. Their shells are composed of numerous nanocrystals (about 40 nm in diameter). The morphology and size of the CaF2 products are strongly dependent on experimental parameters such as reaction time, pH value, and organic additives. The size of the CaF2 hollow spheres can be controlled from 300 to 930 nm by adjusting the pH value. Nitrogen adsorption–desorption measurements suggest that mesopores (av 24.6 nm) exist in these hollow spheres. In addition, Ce3+/Tb3+‐codoped CaF2 hollow spheres can be prepared similarly, and show efficient energy transfer from Ce3+ to Tb3+ and strong green photoluminescence of Tb3+ (541 nm, 5D4→7F5 transition of Tb3+, the highest quantum efficiency reaches 77 %). The monodisperse CaF2:Ce3+/Tb3+ hollow spheres also have desirable properties as drug carriers. Ibuprofen‐loaded CaF2:Ce3+/Tb3+ samples still show green luminescence of Tb3+ under UV irradiation, and the emission intensity of Tb3+ in the drug‐carrier system varies with the released amount of ibuprofen, so that drug release can be easily tracked and monitored by means of the change in luminescence intensity. The formation mechanism and luminescent and drug‐release properties were studied in detail.
Asymmetric Organocatalytic Rearrangement Reactions
Authors: Moyano Albert , El‐Hamdouni Niama , Atlamsani Ahmed 
Published: April 2010

AbstractRearrangement reactions often lead to the regio‐ and stereoselective formation of carbon–carbon or carbon–heteroatom bonds, and allow the construction of otherwise hard‐to‐access molecular frameworks. Research disclosed in the present decade, especially in the last two years, has shown that organocatalytic modes of activation can be successfully applied to a variety of rearrangements. In this Minireview we discuss the advances achieved so far in asymmetric organocatalytic rearrangement reactions.
Anion‐Assisted Complexation of Paraquat by Cryptands Based on Bis(m‐phenylene)‐[32]crown‐10
Authors: Zhu Kelong , Wu Ling , Yan Xuzhou , Zheng Bo , Zhang Mingming , Huang Feihe 
Published: April 2010

AbstractThe complexation of tightly ion‐paired divalent salts such as paraquat dichloride by cryptands based on crown ethers can be improved by the introduction of ion‐pair recognition as a means of also binding the counteranions. A series of diamide‐based cryptands derived from bis(m‐phenylene)‐[32]crown‐10 and designed to complex the bipyridinium dication with anion assistance was synthesized. The ion‐pair recognition process was fully characterized by 1H NMR spectroscopy, UV/Vis spectroscopy, electrospray ionization mass spectrometry and single crystal X‐ray analysis. 1H NMR spectroscopy demonstrated that these new heteroditopic cryptand hosts can complex both the positive and negative components of the paraquat dichloride salt. UV/Vis spectroscopy showed that the addition of chloride anion into equimolar solutions of cryptands 3 c or 3 g with paraquat bis(hexafluorophosphate) salt (2 a) improves the binding of the cryptands to the paraquat guest. Electrospray ionization mass spectrometry and single‐crystal X‐ray analysis confirmed the 1:1 stoichiometries and ion‐pair recognition of these cryptand/paraquat complexes. It was found that the cryptand 3 g, with 13 atoms and an isophthalamide moiety in the third chain, exhibited the best binding affinity for tightly ion‐paired paraquat dichloride (2 b), due to the combination of its spatial compatibility and additional anion‐binding site.
Synthesis of Sugar‐Based Silica Gels by Copper‐Catalysed Azide–Alkyne Cycloaddition via a Single‐Step Azido‐Activated Silica Intermediate and the Use of the Gels in Hydrophilic Interaction Chromatography
Authors: Moni Lisa , Ciogli Alessia , D'Acquarica Ilaria , Dondoni Alessandro , Gasparrini Francesco , Marra Alberto 
Published: April 2010

AbstractNovel sugar‐based silica gels were prepared by exploiting the copper‐catalysed azide–alkyne cycloaddition (CuAAC) of two different sugar alkynes, namely, ethynyl C‐galactoside 1 and propargyl O‐lactoside 2, with new single‐step azido‐activated silica gels. The fully characterised stationary phases were generally used for hydrophilic interaction chromatography (HILIC), with particular application in the stereoselective separation of monosaccharides. Dynamic HILIC (DHILIC) experiments were performed to evaluate the influence of mutarotation on the chromatographic peak shapes of two interconverting sugar anomers. The potential of such materials was shown in the separation of other highly polar compounds, including amino acids and flavonoids.
2‐(p‐Tolylsulfinyl)benzyl Halides as Efficient Precursors of Optically Pure trans‐2,3‐Disubstituted Aziridines
Authors: Arroyo Yolanda , Meana Ángela , Sanz‐Tejedor M. Ascensión , Alonso Inés , García Ruano José Luis 
Published: April 2010

AbstractAziridination of (R)‐N‐sulfinylaldimines (aryl, heteroaryl and alkenyl derivatives) with 2‐(p‐tolyl sulfinyl)benzyl iodide in the presence of sodium hexamethyl disilazide takes place with almost complete control of the stereoselectivity (facial and anti/syn) and with very high yields affording optically pure N‐sulfinyl trans‐2,3‐disubstituted aziridines 7. Simultaneous removal of both C‐ and N‐p‐tolylsulfinyl groups with tBuLi provides the corresponding trans‐NH aziridines 8 without affecting their optical purity. Some experimental results suggest these processes evolve through benzyl halocarbenoids as intermediates, whereas theoretical calculations support the formation of benzyl carbanions. These results have served for revising the mechanistic aspects of the reactions of substituted 2‐p‐tolylsulfinyl benzylcarbanions with electrophiles.
Hybrid Porous Materials with High Surface Area Derived from Bromophenylethenyl‐Functionalized Cubic Siloxane‐Based Building Units
Authors: Chaikittisilp Watcharop , Sugawara Ayae , Shimojima Atsushi , Okubo Tatsuya 
Published: April 2010

AbstractSonogashira cross‐coupling of bromophenylethenyl‐terminated cubic, double four‐ring, siloxane cages with di‐/triethynyl compounds results in microporous poly(ethynylene aryleneethenylene silsesquioxane) networks, simply termed as polyorganosiloxane networks (PSNs). In comparison with porous organic polymers reported previously, these PSNs show relatively high surface area and comparable thermal stability. Their apparent BET specific surface areas vary in the range of 850–1040 m2 g−1 depending on the length and the connectable sites of the ethynyl compounds. Analyses of pore size distribution revealed bimodal micropores with relatively narrow distribution. The degree of cross‐linking affects the degree of cleavage of the siloxane bonds, and this suggests that partial cleavage of the siloxane cages is mainly a result of cage distortion. Hydrogen adsorption was performed to evaluate potential of the PSNs as hydrogen storage media. Uptakes of up to 1.19 wt % at 77 K and 760 Torr and initial isosteric heats of adsorption as high as 8.0 kJ mol−1 were observed. These materials have been obtained by a combination of structural, synthetic organic, and materials chemistry, which can exploited to synthesize porous hybrid materials with specifically designed structures and functions.
From the Technical Lime Cycle to a Sea Shell – Qualitative and Quantitative Experiments Related to Lime
Authors: Rudloff Tina , Heimann Rebekka 
Published: April 2010

AbstractEs werden einerseits qualitative Experimente beschrieben, mit denen der Kalkkreislauf problemorientiert und phänomenologisch erarbeitet werden kann. Zum anderen wird ein einfaches quantitatives Experiment zur Ermittlung des Kalkgehalts biologischer Materialien wie Eierschalen und Muscheln vorgestellt, das mit einfachen Berechnungen ausgewertet werden kann.
Clinical Significance of Awake Oscillatory Ventilation in Patients with Heart Failure and Effects of Open‐Heart Surgery
Authors: Ueshima Kenji , Kobayashi Noboru , Yamazaki Takuya , Saitoh Masahiko , Nakamura Motoyuki , Nakao Kazuwa 
Published: April 2010

AbstractBackgroundAlthough sleep apnea has recently become a concern in patients with congestive heart failure (CHF), some patients with CHF exhibit characteristic oscillatory ventilation (OV) even when they are awake. We investigated the clinical significance of OV in patients with CHF, and effects of open‐heart surgery on the OV.HypothesisOV is an indicator of the severity of CHF, and this abnormal respiratory pattern improves with hemodynamic changes after open‐heart surgery.MethodsAccording to respiratory pattern in the cardiopulmonary exercise testing (CPX) before cardiac surgery, 50 patients with CHF were divided into 14 patients of OV‐positive (OV+) and 36 patients of OV‐negative (OV−). Then, the several indices of CPX before surgey, 1 week and 6 months after surgery were compared between the 2 groups.ResultsThe peak VO2 before surgery was lower in OV+ patients than those in OV− patients (15.3 vs 18.8 m1/min/kg, p < 0.05). One week after surgery, anaerobic threshold (AT) and end‐tidal C02 (ETC02) were lower in OV+ patients than those in OV− patients (AT: 9.5 vs 10,7 ml/min/kg, p < 0.05, ETCO2: 5.3 vs 5.6%, p < 0.05). However, 6 months after surgery, the statistical differences of these CPX parameters between the 2 groups were not found, and OV disappeared in 79% of OV+ patients.ConclusionsThese data suggest that OV is an indicator of the severity of CHF, and gradually improved with the open‐heart surgery. Copyright © 2010 Wiley Periodicals, Inc.
High‐Field2H‐Mims‐ENDOR Spectroscopy on PSII Single Crystals: Hydrogen Bonding of YD.
Authors: Keßen Sven , Teutloff Christian , Kern Jan , Zouni Athina , Bittl Robert 
Published: April 2010

AbstractHydrogen bonds are key determinants for protein structures and the fine‐tuning of active‐site properties. For example, they are responsible for the redox potential variability of protein‐imbedded chromophores. By applying high‐field (94 GHz) Mims‐ENDOR spectroscopy on deuterium‐exchanged frozen‐solution samples and single crystals of photosystem II fromTh. elongatus, we identified the hydrogen‐bonding partner of the tyrosyl radical D2‐Tyr160, YD., directly by the strength and orientation of the deuterium hyperfine coupling as D2‐His189, that is, without relying on the disappearance of a hyperfine coupling interaction upon deletion of D2‐His189. No indications for additional hydrogen bonds can be found in the spectra, thereby eliminating hypotheses about a water network as hydrogen‐binding partner of YD..
Cellular retinol binding protein 1 modulates photoreceptor outer segment folding in the isolated eye
Authors: Wang XiaoFei , Tong Yiai , Giorgianni Francesco , Beranova‐Giorgianni Sarka , Penn John S. , Jablonski Monica M. 
Published: April 2010

AbstractIn a previous study, we used differential proteomics to identify retinal proteins whose steady‐state levels were altered in an experimental system in which photoreceptor outer segments were improperly folded. We determined that the steady‐state level of cellular retinol binding protein 1 (CRBP1) was downregulated in eyes lacking organized outer segments. The purpose of this study was to determine if CRBP1 is a plausible candidate for regulating outer segment assembly. We used Morpholinos to directly test the hypothesis that a decreased level of CRBP1 protein was associated with the misfolding of outer segments. Results from these studies indicate that downregulation of CRBP1 protein resulted in aberrant assembly of outer segments. Because CRBP1 plays a dual role in the retina—retinal recycling and generation of retinoic acid—we evaluated both possibilities. Our data demonstrate that outer segment folding was not modified by 11‐cis retinal supplementation, suggesting that CRBP1 influences outer segment assembly through a mechanism unrelated to rhodopsin regeneration. In contrast, retinoic acid is required for the proper organization of nascent outer segment membranes. The localization of CRBP1 within Muller cells and the RPE and its demonstrated role in modulating the proper folding of nascent outer segment membranes through retinoic acid further elucidates the role of these cells in directly influencing photoreceptor physiology. © 2010 Wiley Periodicals, Inc. Develop Neurobiol 70: 623–635, 2010
Evolution of programmed cell fusion: Common mechanisms and distinct functions
Authors: Oren‐Suissa Meital , Podbilewicz Benjamin 
Published: April 2010

AbstractEukaryotic cells have evolved diverged mechanisms to merge cells. Here, we discuss three types of cell fusion: (1) Non‐self‐fusion, cells with different genetic contents fuse to start a new organism and fusion between enveloped viruses and host cells; (2) Self‐fusion, genetically identical cells fuse to form a multinucleated cell; and (3) Auto‐fusion, a single cell fuses with itself by bringing specialized cell membrane domains into contact and transforming itself into a ring‐shaped cell. This is a new type of selfish fusion discovered in C. elegans. We divide cell fusion into three stages: (1) Specification of the cell‐fusion fate; (2) Cell attraction, attachment, and recognition; (3) Execution of plasma membrane fusion, cytoplasmic mixing and cytoskeletal rearrangements. We analyze cell fusion in diverse biological systems in development and disease emphasizing the mechanistic contributions of C. elegans to the understanding of programmed cell fusion, a genetically encoded pathway to merge specific cells. Developmental Dynamics 239:1515–1528, 2010. © 2010 Wiley‐Liss, Inc.
Caenorhabditis elegans as a model for stem cell biology
Authors: Joshi Pradeep M. , Riddle Misty R. , Djabrayan Nareg J.V. , Rothman Joel H. 
Published: April 2010

AbstractAn adult transgenic C. elegans expressing membrane targeted GFP and mCherry::Histone 2B fusion proteins that demarcate the cell membrane boundaries and nuclei respectively. Strong expression is seen throughout the germline and perdures through embryonic development. From Joshi et al., Developmental Dynamics 239:1539–1554, 2010.