bluuebunny/crossref_metadata_2025_split huggingface dataset:
NF‐kB induces lung maturation during mouse lung morphogenesis
Authors: Londhe Vedang A. , Nguyen Hanh T. , Jeng Jade‐Ming , Li Xia , Li Changgong , Tiozzo Caterina , Zhu Nianling , Minoo Parviz 
Published: December 2007

AbstractLung maturation is hallmarked by the appearance of surfactant‐producing alveoli during transition from the saccular to alveolar stage of lung development. Inflammation can disrupt this process and accelerate lung maturity following intrauterine amniotic infection (chorioamnionitis). Nuclear factor kB (NF‐kB) is a transcription factor central to multiple inflammatory and developmental pathways, including dorsal–ventral patterning in fruit flies, limb and mammary and submandibular gland development in mice, and branching morphogenesis in chick lungs. Given its shared role in inflammation and developmental signaling, we hypothesized that overexpression of NF‐kB targeted to the lung epithelium would exert maturational effects on alveolar development. We generated transgenic mice with lung‐specific overexpression of the RelA subunit of NF‐kB using a surfactant protein C promoter construct. Our results showed that RelA overexpression in the lung yields increased alveolar type I and type II cells. These findings are consistent with a model whereby NF‐kB may induce maturation of lung development through decreased apoptosis of epithelial cells. Developmental Dynamics 237:328–338, 2008. © 2007 Wiley‐Liss, Inc.
System for tamoxifen‐inducible expression of cre‐recombinase from the Foxa2 locus in mice
Authors: Park Eon Joo , Sun Xiaoxia , Nichol Peter , Saijoh Yukio , Martin James F. , Moon Anne M. 
Published: December 2007

AbstractTo study the roles of key transcription factor networks, growth factors, and signaling molecules in the endoderm, notochord, and floorplate, we developed an inducible Cre‐expressing system for altering gene function in this tissue. We generated an allele of Foxa2 that directs a tamoxifen‐regulated Cre in the Foxa2 expression domain (Foxa2mcm). Activity of Foxa2mcm recapitulates endogenous Foxa2 expression in endoderm, notochord, and floorplate. Efficiency of the system in a given tissue type was dose‐ and timing‐dependent. By comparing efficiency and location of Cre activity after administration of tamoxifen by oral gavage vs. intraperitoneal injection, we found that oral gavage achieves more rapid, robust recombination with less embryonic toxicity. This system will be useful for controlling the activity of floxed alleles at multiple stages of mouse embryogenesis and fetal development. Developmental Dynamics 237:447–453, 2008. © 2007 Wiley‐Liss, Inc.
Recent applications in CEC
Authors: Huo Yuli , Kok Wim Th. 
Published: December 2007

AbstractIn this review, research papers on CEC are summarized that have been published between May 2005 and May 2007. Application‐oriented research is discussed in which CEC is used in biochemical and pharmaceutical studies, in the analysis of food and natural products, and in industrial, environmental, and forensic analysis. Some trends and developments in separation science that may increase the applicability of the separation technique CEC are highlighted: 2‐D separation systems and the application of nano‐ and microfluidic devices in separations.
Ionic liquids and CE combination
Authors: López‐Pastor Mercedes , Simonet Bartolomé M. , Lendl Bernhard , Valcárcel Miguel 
Published: December 2007

AbstractThis paper reviews and discusses the analytical combination of ionic liquids (IL) with CE. On the one hand, it shows CE as a powerful technique to separate impurities from IL as well as being capable to determine physical and chemical properties of IL. On the other hand, it also shows how IL are employed in CE separations to enhance resolution, peak efficiency and peak symmetry. Specifically, IL are used as additives in CZE, NACE, and MEKC and as support coatings of the capillary wall in electrochromatography. The integrity of the IL in the electrophoretic system as well as the roles of the cations and anions of the IL in the electrophoretic separation are also discussed.
Microemulsion electrokinetic chromatography hyphenated to atmospheric pressure photoionization mass spectrometry
Authors: Schappler Julie , Guillarme Davy , Rudaz Serge , Veuthey Jean‐Luc 
Published: December 2007

AbstractCZE is an appropriate technique for separating charged species, but lacks selectivity for neutral compounds. Alternative approaches such as microemulsion electrokinetic chromatography (MEEKC) have been developed to broaden its range of applications. Hyphenation of MEEKC with MS is an attractive perspective since it can enhance sensitivity and selectivity. The on‐line coupling of MEEKC with MS, however, is not straightforward due to the low compatibility of non‐volatile surfactant additives (e.g. SDS) and the commonly used API source, namely ESI. In order to hyphenate MEEKC with MS detection, the atmospheric pressure photoionization (APPI) source was investigated. Possibilities offered by the coupling of MEEKC with APPI‐MS were highlighted for the complex separation of ionized and neutral compounds in both the positive and negative modes. MEEKC‐APPI‐MS performance, in terms of selectivity, efficiency and sensitivity was compared to CZE‐ESI‐MS and MEEKC‐ESI‐MS for the screening of doping substances (β‐blockers, central stimulants, diuretics, etc). Relevant selectivity and detectability, particularly for neutral, structurally related and isobaric compounds was demonstrated with the MEEKC‐APPI‐MS approach opening new avenues for CE‐MS, in addition to the well‐established CZE‐ESI‐MS technique.
Trends in CE‐MS 2005–2006
Authors: Gaspar Andras , Englmann Matthias , Fekete Agnes , Harir Mourad , Schmitt‐Kopplin Philippe 
Published: December 2007

AbstractCE‐MS has gained further attention as a multidimensional analytical approach. The number of publications dealing with this technique is still increasing on the level of application as well as method development‐oriented approaches. Additionally, 15 reviews were published the last two years focusing on CE‐MS. An overview of all papers found to have been published within 2005 and 2006 is given in tabulated form. Additionally, four promising technical trends are chosen to be presented in detail: (i) chip‐based CE‐MS, (ii) capillary coatings in CE‐MS, (iii) new trends in CEC‐MS and (iv) the application of 2‐D CE‐MS.
A note on classical damping matrices
Authors: Luco J. Enrique 
Published: December 2007

AbstractAn alternative damping matrix that leads to classical normal modes and that depends explicitly on a set of prescribed modal damping ratios is presented. The alternative damping matrix can be thought of as a factorized Caughey series that allows for a simple explicit solution for the coefficients of the series and thus avoids the need to solve a potentially ill‐conditioned system of algebraic equations. The relation between the proposed damping matrix and Rayleigh, Caughey and modal damping matrices is examined. Copyright © 2008 John Wiley & Sons, Ltd.
Variants of projection‐based finite element variational multiscale methods for the simulation of turbulent flows
Authors: John Volker , Kindl Adela 
Published: December 2007

AbstractSome variants of a three‐scale projection‐based finite element variational multiscale (VMS) method are studied for turbulent channel flow computations at Reτ=180. Different spaces for the large scales, two eddy viscosity models and two ways of discretizing the projection terms in time are explored. The results obtained with the resolved small scales in the definition of the eddy viscosity are very sensitive to the temporal discretization of the projection terms. The computations were performed on three grids commonly used in turbulent channel flow simulations. Copyright © 2007 John Wiley & Sons, Ltd.
Wenn Sternleichen Signale senden
Authors: Lesch Harald , Jessner Axel 
Published: December 2007

AbstractKosmische Elektrotechnik: Pulsare strahlen intensiver als jedes andere Objekt im Universum. Astrophysiker sind den rotierenden Neutronensternen auf der Spur – und finden dabei die Naturgesetze der Erde auch am Rande der Materie bestätigt
Das Geheimnis der grünen Haut
Authors: Karsten Ulf , Schumann Rhena , Gustavs Lydia , Friedl Thomas 
Published: December 2007

AbstractSie sind überall: Mikroalgen besiedeln Hausfassaden, Böden und Bäume. Selbst widrige Lebensumstände stören die Algengemeinschaften kaum. Wie sich die Biofilme schützen und immer wieder an ihre Umwelt anpassen, interessiert auch Grundlagenforscher
The synthesis and characterization of polymerizable and biocompatible N‐maleic acyl‐chitosan
Authors: Zhu Aiping , Pan Yingnan , Liao Tianqing , Zhao Feng , Chen Tian 
Published: December 2007

AbstractBiocompatible and polymerizable natural macromolecules have been found to provide great advantages in the preparation of hydrogels, which have wide applications in the fields of tissue engineering and polymeric drug delivery systems. To develop a new biocompatible polymerizable chitosan derivative, N‐maleic acyl‐chitosan (NMCS) was synthesized in this study. This novel biomaterial was designed from the N‐acylation of chitosan with maleic anhydride introducing functional carboxyl and vinylated (CC) groups. The structure of NMCS was characterized by FTIR, 1H NMR, element analysis, and X‐ray diffraction (XRD). NMCS can be dissolved into water because of its decreased crystallinity compared with chitosan. The NMCS's multiporous and microgel morphology was revealed by transmission electron microscope (TEM). Crosslinked hydrogel films can be successfully obtain through the macromolecular polymerization of NMCS. Subsequently, 3T3 fibroblasts were cultured onto the surface of the polymerized NMCS (P‐NMCS) films to examine the capability of cell attachment and proliferation. Results from the cell culture demonstrate that P‐NMCS films provide significant improvement in cell attachment and proliferation over unmodified chitosan. The improved P‐NMCS cytocompatibility is expected to provide substantial contributions to tissue engineering in the future. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2008
In vitro degradation and in vivo biocompatibility of poly(lactic acid) mesh for soft tissue reinforcement in vaginal surgery
Authors: de Tayrac Renaud , Chentouf Samir , Garreau Henri , Braud Christian , Guiraud Isabelle , Boudeville Philippe , Vert Michel 
Published: December 2007

AbstractThis study was aimed at evaluating the in vitro degradation, the in vivo biocompatibility and at comparing the effects of two methods of sterilization on poly(L‐lactic acid) (PLA94) resorbable mesh. The mesh was manufactured to be used as surgical soft tissue reinforcement in the vaginal area. Samples of 100 mg of PLA94 mesh (10 × 10 mm2) were immersed in isoosmolar 0.13M, pH 7.4 phosphate buffer solution at 37°C, during 12 months. The hydrolytic degradation up to 12 months after immersion was monitored by measuring weight loss, mesh area changes, and by various analytical techniques namely Differential scanning calorimetry (DSC), capillary zone electrophoresis (CZE), size exclusion chromatography (SEC), and environmental scanning electron microscopy (ESEM). Specimens of nonsterilized, ethylene‐oxide (ETO) sterilized, and γ‐ray sterilized PLA94 mesh were compared. Fifteen samples were implanted in an incisional hernia Wistar rat model. Histopathology was performed up to 90 days after implantation to evaluate the inflammatory response and the collagen deposition. Although the decrease of molecular weight due to polymer chain scissions started 6 weeks after in vitro immersion, water‐soluble degradation products and decrease of tensile strength appeared after 8 months only. Analyses showed also that ETO sterilization did not affect the degradation of the PLA94 mesh. In contrast, γ‐ray sterilization increased very much the sensitivity of the mesh to the hydrolytic degradation. In vivo, the PLA94 mesh exhibited good biocompatibility over the investigated time period. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2008
Bone regeneration by using scaffold based on mineralized recombinant collagen
Authors: Wang Y. , Cui F. Z. , Hu K. , Zhu X. D. , Fan D. D. 
Published: December 2007

AbstractBone regeneration was achieved in the 15‐mm segmental defect model in the radius of rabbit by using the scaffold based on mineralized recombinant collagen for the first time. The recombinant collagen was recombinant human‐like type I collagen, which was produced by cloning a partial cDNA that was reversed by mRNA from human collagen α1(I) and transferred to E. coli. The scaffold material nano‐hydroxyapatite/recombinant human‐like collagen/poly(lactic acid) (nHA/RHLC/PLA) was developed by biomimetic synthesis. Thermo gravimetric analysis, X‐ray diffraction and scanning electron microscopy were applied to exhibit that the scaffold showed some features of natural bone both in main component and hierarchical microstructure. The percentages of organic phase and inorganic phase of nHA/RHLC were similar to that of natural bone. The three‐dimensional porous scaffold materials mimic the microstructure of cancellous bone. In the implantation experiment, the segmental defect was healed 24 weeks after surgery, and the implanted composite was completely substituted by new bone tissue. The results of the implantation experiment were very comparable with that of the scaffold based on mineralized animal‐sourced collagen. It is concluded that the scaffold based on mineralized recombinant collagen maintains the advantages of mineralized animal‐sourced collagen, while avoids potential virus‐dangers. The scaffold is a promising material for bone tissue engineering. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2008
Neural tissue engineering of the CNS using hydrogels
Authors: Nisbet David R. , Crompton Kylie E. , Horne Malcolm K. , Finkelstein David I. , Forsythe John S. 
Published: December 2007

AbstractCurrent therapies have limited capacity to curtail disease progression or damage of the central nervous system (CNS) of adult mammals and successful regeneration following injury or disease does not occur. Regeneration of the CNS is limited by physical and chemical inhibitory barriers within the injured environment and the absence of positive cues that elicit and guide repair. Neural tissue engineering strategies focus on developing scaffolds that artificially generate favourable cellular microenvironments that attempt to tip the balance in favour of regeneration. Some recent advances using scaffolds to promote regeneration within the CNS, particularly in conjunction with stem cells, has generated promising results. This review focuses on hydrogel scaffolds which have been used extensively in neural tissue engineering applications and addresses the physical and chemical modifications of these materials to promote nerve regeneration. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2008
Study of the micro‐structural properties of RISUG®—A newly developed male contraceptive
Authors: Kumar Sunil , Roy Sohini , Chaudhury Koel , Sen Prasenjit , Guha Sujoy K. 
Published: December 2007

AbstractA new male contraceptive given the name RISUG® (an acronym for reversible inhibition of sperm under guidance) and presently undergoing advanced clinical trials has been developed. When injected into the lumen of the vas deferens, its polyelectrolytic nature induces a surface charge imbalance on sperm membrane system leading to the leakage of enzymes essential for fertilization. Contact mode atomic force microscopy (AFM) has been used to analyze quantitatively the micro‐structural properties of RISUG® and its precipitate in various systems. Hydrolysis of the contraceptive gel resulted in the formation of pores of varying dimensions. RISUG® being a highly charged molecule, as evident from zeta potential measurements, has a tendency to form a complex with ionic biomolecules present in the seminal plasma. This is supported by the experimental observations using AFM. This RISUG®‐biomolecule complex possibly acts as an ionic trap for spermatozoa passing through the vas deferens. Micro‐structural properties of RISUG® including amplitude (root mean square, peak‐to‐valley distance, skewness and kurtosis) and spatial roughness have been studied to understand its response to various physiological conditions. Significant alterations in the surface charge distribution of the sperm cell is observed on exposure to RISUG®. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2008
Effect of In vitro degradation of poly(D,L‐lactide)/β‐tricalcium composite on its shape‐memory properties
Authors: Zheng Xiaotong , Zhou Shaobing , Yu Xiongjun , Li Xiaohong , Feng Bo , Qu Shuxin , Weng Jie 
Published: December 2007

AbstractThe in vitro degradation characteristic and shape‐memory properties of poly(D,L‐lactide) (PDLLA)/β‐tricalcium phosphate (β‐TCP) composites were investigated because of their wide application in biomedical fields. In this article, PDLLA and crystalline β‐TCP were compounded and interesting shape‐memory behaviors of the composite were first investigated. Then, in vitro degradation of the PDLLA/β‐TCP composites with weight ratios of 1:1, 2:1, and 3:1 was performed in phosphate buffer saline solution (PBS) (154 mM, pH 7.4) at 37°C. The effect of in vitro degradation time for PDLLA/β‐TCP composites on shape‐memory properties was studied by scanning electron microscopy, differential scanning calorimetry, gel permeation chromatography, X‐ray diffraction (XRD), and Fourier transform infrared spectroscopy (FTIR). The changes of structural morphology, glass transition temperature (Tg), molecular weight, and weight loss of composites matrix and pH change of degradation medium indicated that shape‐memory effects at different degradation time were nonlinearly influenced because of the breaking down of polymer chain and the formation of degradation products. Furthermore, the results from XRD and FTIR implied that the degradation products, for example, hydroxyapatite (HA), calcium hydrogen phosphate (CaHPO4), and calcium pyrophosphate (Ca2P2O7) phases also had some effects on shape‐memory properties during the degradation. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2008
Comparative histomorphometric and tomographic analysis of maxillary sinus floor augmentation in rabbits using autografts and xenografts
Authors: Sicca Cristina Miguel , Corotti Mauro Vinícius , Sgarbosa Sílvia Helena Pereira Vergili , Cestari Tania Mary , Cavalcanti Marcelo Gusmão Paraíso , Ferreira Paulo Martins , Taga Rumio , Granjeiro José Mauro 
Published: December 2007

AbstractOur goal was to evaluate bone neoformation promoted by a bovine xenograft composite (XC) compared with autogenous graft for maxillary sinus augmentation in a rabbit model. The left maxillary sinus of 18 male rabbits was filled with 200 mg of cortical and cancellous autogenous bone and the right sinus was filled with 200 mg of a composite comprised organic and inorganic bovine matrices, pool of bBMPs and collagen. Postoperative implant intervals of 2, 4, and 8 weeks were analyzed. Differences in the bone optical density among the groups and experimental periods were evaluated by computed tomography analysis. The tissue response was evaluated by histomorphometric analysis of the newly formed bone, connective tissue and/or granulation tissue, residual material, and bone marrow. The tomographic analyses showed a maximum optical density in the 4‐week period for both groups. Histologically, an inflammatory infiltrate was observed at 2 weeks in the XC group but exclusively around the organic particles of the biomaterial. Regarding to the amount of newly formed bone, no statistical differences (p > 0.05) were observed among the two treatments throughout the implant intervals. However, by the end of the 8 weeks, the quantity of bone marrow was two times greater (p < 0.05) in the control group than in the XC group. In conclusion, the xenograft composite promotes formation of new bone in a similar fashion to autogenous bone and could therefore be considered a biomaterial with potential applications as a bone substitute in maxillary sinus floor augmentation. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2008
Transmission electron microscopy and electron diffraction study of BSA‐loaded quaternized chitosan nanoparticles
Authors: Wan A‐jun , Sun Yan , Li Wen‐tao , Li Hui‐li 
Published: December 2007

AbstractChitosan nanoparticles, O‐(2‐hydroxyl) propyl‐3‐trimethyl ammonium chitosan chloride (O‐HTCC) nanoparticles and bovine serum albumin (BSA) loaded chitosan and O‐HTCC nanoparticles of a size (about 200–600 nm) were obtained through the process of ionic gelation between chitosan or O‐HTCC and sodium tripolyphosphate (TPP). The physicochemical properties of nanoparticles made from chitosan, O‐HTCC, BSA loaded chitosan, and BSA loaded O‐HTCC were determined by transmission electron microscopy (TEM), polarized optical microscopy (POM), photon correlation spectroscopy (PCS), and X‐ray diffraction (XRD) pattern. Zeta potential was also performed to understand the surface properties of nanoparticles and their ability to bind negatively charged BSA. TEM, POM, and XRD suggested that ionic‐gelation process significantly influenced the crystallinity of BSA, and greater chain realignment in the BSA‐loaded chitosan and O‐HTCC nanoparticles. PCS revealed that BSA‐loaded chitosan nanoparticles were bigger than chitosan nanoparticles in size and BSA‐loaded O‐HTCC nanoparticles were smaller than O‐HTCC nanoparticles in size. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2008
Polypeptide‐catalyzed silica for dental applications
Authors: Advincula Maria C. , Patel Pritesh , Mather Patrick T. , Mattson Tyler , Goldberg A. Jon 
Published: December 2007

AbstractPolypeptides such as polylysine have been shown to catalyze the condensation and direct the structure of silica from precursor solutions under ambient conditions. Several of the reaction parameters have been shown to mediate this activity. Specifically, mechanical perturbation seems to play a role in the formation of hierarchical structures. Most studies have been conducted in solution, but biomedical and particularly dental applications will likely require control of biosilicified coatings, films or particle formation on surfaces. Tetraethylorthosilicate was reacted with polylysine and then spin coated onto a surface. The process parameters catalyst structure, pH, buffer: ethanol ratio and percentage of cocatalyst polyethyleneimine were varied to determine their effects on the formed silica. The chemical nature and morphology of the silica were investigated with FTIR and SEM, respectively and reaction rates were monitored with a colorimetric assay. Our results show that these process parameters had only minor effects on composition, but the catalyst conformation influenced the degree of hydration while the pH, choice of solvent and cocatalyst strongly influenced morphology. We also found that perturbation from spin coating significantly influences the silicification dynamics. The ability to catalyze nano‐ to micron‐sized mineral with different morphologies using polypeptides could have numerous dental applications including, sealing of dentin tubules, in situ reinforcement of resin interfaces or preparation of implant surfaces. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2009