bluuebunny/crossref_metadata_2025_split huggingface dataset:
Hyperforin and aristoforin inhibit lymphatic endothelial cell proliferation in vitro and suppress tumor‐induced lymphangiogenesis in vivo
Authors: Rothley Melanie , Schmid Anja , Thiele Wilko , Schacht Vivien , Plaumann Diana , Gartner Michael , Yektaoglu Aybike , Bruyère Françoise , Noël Agnès , Giannis Athanassios , Sleeman Jonathan P. 
Published: January 2009

AbstractThe phloroglucinol derivative hyperforin, a major bioactive constituent of St. John's wort, is increasingly recognized as being able to regulate a variety of pathobiological processes and, thus, to possess potential therapeutic properties. In the context of cancer, hyperforin induces the apoptosis of cancer cells, inhibits angiogenesis and suppresses metastasis formation. Here, we report a new pharmacological function of hyperforin and its stabilized derivative aristoforin, namely the suppression of lymphatic endothelial cell (LEC) growth and lymphangiogenesis. At concentrations less than 10 μM, we found that these compounds induce cell cycle arrest of LECs, and at higher concentrations induce apoptosis. The loss of mitochondrial membrane potential and the activation of caspase‐9 during the induction of apoptosis indicate that the intrinsic pathway of apoptosis is stimulated by these compounds, similar to the situation in tumor cells. In thoracic duct ring outgrowth assays, hyperforin and aristoforin both inhibited lymphangiogenesis, as evidenced by the suppression of lymphatic capillary outgrowth. In an in vivo animal model, both compounds were able to inhibit tumor‐induced lymphangiogenesis. Together these data substantiate a new role for hyperforin and its derivatives as suppressors of lymphangiogenesis, and support their further investigation as potential anticancer drugs that target tumor growth and metastasis at multiple levels. © 2009 UICC
Optimal design of water‐conveying canal considering seismic stability of side slopes
Authors: Bhattacharjya Rajib Kumar , Satish Mysore G. 
Published: January 2009

AbstractA new methodology is proposed in this study for determination of a cost‐effective canal section considering the seismic stability of homogeneous canal side slopes. In order to consider the seismic stability of canal side slopes, an external seismic slope stability model is required to incorporate with the canal optimization model. During the iterations for optimal solution, the canal optimization model uses the seismic stability model at every iteration. As a result, the efficiency of the combined model is mostly dependent on the efficiency of the seismic slope stability model. The computational efficiency of the combined model can be enhanced using an approximate model to check the stability of the side slope of the canal. Therefore, an artificial neural network (ANN) model is used in this study to approximate the seismic slope stability model. The developed ANN model is linked externally with the canal optimization model to obtain the dimensions of the cost‐effective canal section with seismic‐resistant side slopes. Pseudo‐static analysis is carried out for evaluation of the seismic stability of the slope. An example problem is solved to demonstrate the field applicability of the developed model. Copyright © 2009 John Wiley & Sons, Ltd.
Phosphatidylserine decarboxylases, key enzymes of lipid metabolism
Authors: Schuiki Irmgard , Daum Günther 
Published: January 2009

AbstractPhosphatidylserine decarboxylases (PSDs) (E.C. 4.1.1.65) are enzymes which catalyze the formation of phosphatidylethanolamine (PtdEtn) by decarboxylation of phosphatidylserine (PtdSer). This enzymatic activity has been identified in both prokaryotic and eukaryotic organisms. PSDs occur as two types of proteins depending on their localization and the sequence of a conserved motif. Type I PSDs include enzymes of eukaryotic mitochondria and bacterial origin which contain the amino acid sequence LGST as a characteristic motif. Type II PSDs are found in the endomembrane system of eukaryotes and contain a typical GGST motif. These characteristic motifs are considered as autocatalytic cleavage sites where proenzymes are split into α‐ and β‐subunits. The S‐residue set free by this cleavage serves as an attachment site of a pyruvoyl group which is required for the activity of the enzymes. Moreover, PSDs harbor characteristic binding sites for the substrate PtdSer. Substrate supply to eukaryotic PSDs requires lipid transport because PtdSer synthesis and decarboxylation are spatially separated. Targeting of PSDs to their proper locations requires additional intramolecular domains. Mitochondrially localized type I PSDs are directed to the inner mitochondrial membrane by N‐terminal targeting sequences. Type II PSDs also contain sequences in their N‐terminal extensions which might be required for subcellular targeting. Lack of PSDs causes various defects in different cell types. The physiological relevance of these findings and the central role of PSDs in lipid metabolism will be discussed in this review. © 2009 IUBMB IUBMB Life, 61(2): 151–162, 2009
Towards oncological application of Raman spectroscopy
Authors: Nijssen Annieke , Koljenović Senada , Schut Tom C. Bakker , Caspers Peter J. , Puppels Gerwin J. 
Published: January 2009

AbstractAs the possibilities in the treatment of cancer continue to evolve, its early detection and correct diagnosis are becoming increasingly important. From the early detection of cancer to the guidance of oncosurgical procedures new sensitive in vivo diagnostic tools are much needed. Many studies report the Raman spectroscopic detection of malignant and premalignant tissues in different sites of the body with high sensitivities. The great appeal of this technique lies in its potential for in vivo clinical implementation. We present an overview of the in vitro and in vivo work on the oncological application of Raman spectroscopy and discuss its potential as a new tool in the clinico‐oncological practice. Opportunities for integration of Raman spectroscopy in oncological cure and care as a real‐time guidance tool during diagnostic (i.e. biopsy) and therapeutic (surgical resection) modalities as well as technical shortcomings are discussed from a clinician's point of view. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Mechanical properties of small‐diameter polyurethane vascular grafts reinforced by weft‐knitted tubular fabric
Authors: Xu Weilin , Zhou Fei , Ouyang Chenxi , Ye Wenxiang , Yao Mu , Xu Bugao 
Published: January 2009

AbstractPolyester filament yarns of different Deniers were knitted into tubular fabrics with different densities and thicknesses on a specially designed weft‐knitting machine. The developed tubular fabric was used to reinforce polyurethane vascular graft and thus a kind of composite vascular graft was fabricated with a small inner diameter of 4 mm. Tensile properties of the reinforced composite vascular grafts were compared with the control tubular fabric and the pure PU vascular grafts. Elasticity and strength of the reinforced vascular grafts were improved compared with the weft‐knitted tubular fabrics. Strength of the reinforced composite vascular grafts was almost 5–10 times of the strength of the pure PU vascular grafts. As the PU content increased in the reinforced composite vascular grafts, the wall thickness of the vascular graft and its strength increased, but the initial modulus of the reinforced composite vascular grafts remained similar to that of the weft‐knitted tubular fabric, and the PU content showed little influence on the initial modulus of the reinforced composite vascular grafts. Microporous structure can also be fabricated in the wall of the reinforced composite vascular grafts. © 2009 Wiley Periodicals, Inc. J Biomed Mater Res, 2010
Response of UMR 106 cells exposed to titanium oxide and aluminum oxide nanoparticles
Authors: Di Virgilio Ana L. , Reigosa Miguel , de Mele Monica Fernández Lorenzo 
Published: January 2009

AbstractThe cytotoxicity potential of TiO2 and Al2O3 nanoparticles (NP) in UMR 106 cells was studied by evaluating the lysosomal activity with neutral red uptake assay (NR), and the mitochondrial activity with tetrazolium MTT test. Different NP concentrations (10–300 μg/mL range) were used. A significant (p < 0.001) increase in the absorbance (stronger for TiO2 NP) was detected in both NR and MTT assays after 24‐h exposure to the NP. However, the total cell proteins and the cell proliferation rate demonstrated (p < 0.05) that the cell viability decreased after 96 h exposure to NP. The formation of NP‐containing vesicles within the cells was observed by transmission electronic microscopy. Such event could explain the high cellular activity detected during the early stages of exposure not related to the increase in cell viability. Results showed that the effects of NP on cell lines are dependent on the chemical composition of the particles, their concentration, exposure time, and the type of treated cell. It can be concluded that the presence of TiO2 and Al2O3 NP in the cell surroundings can lead to cytotoxic effects. In the case of osteoblast cells, such events may induce osseointegration failures in orthopedic and dental implants that release NP. © 2009 Wiley Periodicals, Inc. J Biomed Mater Res, 2010
Expression of Concern: Different apoptosis modalities in periprosthetic membranes
Authors: Sabbatini Maurizio , Piffanelli Valentina , Boccafoschi Francesca , Gatti Silvia , Renò Filippo , Bosetti Michela , Leigheb Massimiliano , Massè Alessandro , Mario Cannas 
Published: January 2009

AbstractThis study reports on an investigation into apoptotic and proliferation signals in leukocyte and membrane fibroblasts in periprosthetic membranes collected during revision surgery for loosened total hip joint arthroplasty. Cementless and cemented prosthesis were studied under both aseptic and septic conditions. Fluorescence colocalization immunohistochemistry and colorimetric immunohistochemistry were used to investigate cell death signals. In aseptic cementless prosthesis macrophages and membrane fibroblasts show high bax signal, implying the occurrence of toxic/oxidative cell death caused by the debris of titanium alloy metal implant. Instead in aseptic cemented prosthesis only a moderate number of apoptotic leukocytes were observed, whilst the fibroblasts were affected by a diffuse apoptotic‐like cell death, the Co‐Cr ions debris released from cemented stem, may be at basis of apoptotic cell death induction. Furthermore cement debris is recognized to induce macrophages to produce cytokine, that may be responsible for the cell death observed and implant failure. The septic environment seems to protect leukocytes cell death. Septic cementless prosthesis showed only a few apoptotic leukocytes, instead fibroblasts remain affected by cell death signals. Similarly in septic cemented prosthesis, scanty apoptotic leukocytes were detected, whereas membrane fibroblasts showed an increase in proliferation index (Ki‐67) along with caspase‐3 activation. These findings indicate some kind of caspase‐3 involvement in tissue proliferation, rather than in cell death pathway. Apoptotic periprosthetic sites have been interpreted as signs of inflammation resolution and normal tissue turnover. Nevertheless apoptosis may also be a sign of cell renewal associated to tissue proliferation. © 2009 Wiley Periodicals, Inc. J Biomed Mater Res, 2010
Sensitivity of insulin production from encapsulated islets to endotoxin‐stimulated macrophage inflammatory mediators
Authors: Lyle Daniel B. , Shallcross Jonathan C. , Langone John J. 
Published: January 2009

AbstractChronic inflammation may compromise function of implanted encapsulated islets. Increased purity of alginate used for encapsulation prolongs encapsulated graft function, correlating with decreased presence of impurities like bacterial endotoxin. Limits for endotoxin contamination in biomaterials based on indirect inhibition of function of embedded cells have yet to be established. In a coculture system with RAW 264.7 monocyte/macrophage cells in the presence of 50 ng/mL murine recombinant gamma‐interferon (mrIFN‐γ), the insulin response to glucose challenge of both rat and pig unencapsulated islets was prevented by endotoxin (LPS) in the medium down to 0.3 EU/mL (LOEL), but not 0.06 EU/mL (NOEL). Evaluation of nitrite concentrations in supernatants revealed that pig islets were more resistant to LPS‐stimulated macrophage mediators than rat islets. Encapsulation in highly purified alginate produced little change in observed inhibitory effects of macrophage‐generated nitric oxide (NO) toward islet function. Chemically released NO was much less effective in inhibiting insulin responsiveness to glucose challenge than was coculture of islets with LPS and mrIFN‐γ‐stimulated RAW 264.7. These results taken together with other data suggest that an upper limit of 0.3 EU/mL LPS within the encapsulating alginate will not impair the function of implanted encapsulated islets by toxic concentrations of macrophage‐mediated inflammatory agents. © 2009 Wiley Periodicals, Inc. J Biomed Mater Res, 2009
Properties of experimental titanium‐silver‐copper alloys for dental applications
Authors: Kang Dong‐Kuk , Moon Seoung‐Kyun , Oh Keun‐Taek , Choi Good‐Sun , Kim Kyoung‐Nam 
Published: January 2009

AbstractThe aim of this study was to develop Ti‐Ag‐Cu alloys with a higher corrosion resistance, better biocompatibility, and better mechanical properties than commercially pure titanium and its alloys. The microstructure, corrosion resistance, mechanical property and cytotoxicity of the Ti‐Ag‐Cu alloys were investigated. The corrosion resistance was evaluated by open circuit potential measurements and potentiodynamic polarization tests in artificial saliva at 37°C. The mechanical properties were evaluated using tensile and microhardness tests. The biocompatibility was tested by evaluating the cytotoxicity of the alloys using an agar‐overlay test and MTT assay. It was found that the open circuit potentials of the Ti‐Ag‐Cu alloys were higher than that of pure Ti. However, the passive current densities of the Ti‐Ag‐Cu alloys were similar to that of pure titanium. The mechanical properties improved with increasing Ag and Cu content. All the Ti‐Ag‐Cu alloys examined were found to be noncytotoxic similar to pure Ti. Therefore, Ti‐Ag‐Cu alloys can be used as biomaterials in the dental field. © 2009 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2009
Effect of spongin derived from Hymeniacidon sinapium on bone mineralization
Authors: Kim Moon‐Moo , Mendis Eresha , Rajapakse Niranjan , Lee Sang‐Hoon , Kim Se‐Kwon 
Published: January 2009

AbstractMarine sponges have been known to provide a source of novel bone and cartilage replacements because of their secondary metabolites and specific skeleton structures. In particular, it has been reported that spongin as a component of fibrous skeleton, pseudokeratin, neurokeratin, horny protein, and collagen‐like protein in sponges can be used in several biomedical applications including osteoarthritis (OA). However, the pharmacological mechanism of action of spongin remains obscure. In this study, it was investigated whether spongin derived from Hymeniacidon sinapium can promote bone mineralization of osteoblast‐like MG‐63 cells. Our present study provides the first evidence that spongin is effective in activating bone mineralization. Furthermore, spongin increased ALP activity, collagen synthesis, and osteocalcin secretion in addition to bone mineralization in osteoblastic cells in vitro. In addition, it was demonstrated that spongin exerted the inhibitory effect on production of inflammatory mediators such as TNF‐α, IL‐1β, and PGE2 in macrophage, RAW264.7 cells. These results suggest that the anti‐inflammatory effect of spongin derived from Hymeniacidon sinapium can play a critical role in bone mineralization of osteoblast‐like MG‐63 cells. © 2009 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2009
Collagen nanofilm immobilized on at surfaces by electrodeposition method
Authors: Yang Xiudong , Jiang Bo , Huang Yi , Tian Yunfei , Chen Hong , Chen Jiyong , Yang Bangcheng 
Published: January 2009

AbstractA simple electrodeposition method is presented for the preparing of collagen nanofilms (EAT) on anodic oxidized titanium surfaces (AT). The nanofilms were observed by scanning electron microscopy and atomic force microscopy. Functional TiOx layers with anionic groups of PO4, SO4 and OH were investigated on the AT surface by X‐ray photoelectron spectroscopy; X‐ray diffraction results indicated that the AT surface was composed mainly of anatase and rutile. The bioactive electrodeposited TiOx layers on the AT surface showed lower water contact angles and higher surface energy than pure titanium surfaces (CT) and displayed higher collagen molecule immobilization. © 2009 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2009
A kernel‐based method to determine optimal sampling times for the simultaneous estimation of the parameters of rival mathematical models
Authors: Donckels Brecht M. R. , De Pauw Dirk J.W. , Vanrolleghem Peter A. , De Baets Bernard 
Published: January 2009

AbstractWhen several models are proposed for one and the same process, experimental design techniques are available to design optimal discriminatory experiments. However, because the experimental design techniques are model‐based, it is important that the required model predictions are not too uncertain. This uncertainty is determined by the quality of the already available data, since low‐quality data will result in poorly estimated parameters, which on their turn result in uncertain model predictions. Therefore, model discrimination may become more efficient and effective if this uncertainty is reduced first. This can be achieved by performing dedicated experiments, designed to increase the accuracy of the parameter estimates. However, performing such an additional experiment for each rival model may undermine the overall goal of optimal experimental design, which is to minimize the experimental effort. In this article, a kernel‐based method is presented to determine optimal sampling times to simultaneously estimate the parameters of rival models in a single experiment. The method is applied in a case study where nine rival models are defined to describe the kinetics of an enzymatic reaction (glucokinase). The results clearly show that the presented method performs well, and that a compromise experiment is found which is sufficiently informative to improve the overall accuracy of the parameters of all rival models, thus allowing subsequent design of an optimal discriminatory experiment. © 2009 Wiley Periodicals, Inc. J Comput Chem, 2009
N2O in small para‐hydrogen clusters: Structures and energetics
Authors: Zhu Hua , Xie Daiqian 
Published: January 2009

AbstractWe present the minimum‐energy structures and energetics of clusters of the linear N2O molecule with small numbers of para‐hydrogen molecules with pairwise additive potentials. Interaction energies of (p‐H2)–N2O and (p‐H2)–(p‐H2) complexes were calculated by averaging the corresponding full‐dimensional potentials over the H2 angular coordinates. The averaged (p‐H2)–N2O potential has three minima corresponding to the T‐shaped and the linear (p‐H2)–ONN and (p‐H2)–NNO structures. Optimization of the minimum‐energy structures was performed using a Genetic Algorithm. It was found that p‐H2 molecules fill three solvation rings around the N2O axis, each of them containing up to five p‐H2 molecules, followed by accumulation of two p‐H2 molecules at the oxygen and nitrogen ends. The first solvation shell is completed at N = 17. The calculated chemical potential oscillates with cluster size up to the completed first solvation shell. These results are consistent with the available experimental measurements. © 2009 Wiley Periodicals, Inc. J Comput Chem, 2009
Hydrodynamic behaviour of a full‐scale anaerobic contact reactor using residence time distribution technique
Authors: Capela Isabel , Bilé Maria João , Silva Flávio , Nadais Helena , Prates António , Arroja Luís 
Published: January 2009

AbstractBACKGROUND: The knowledge of the fluid pattern of full‐scale anaerobic reactors is of fundamental importance for the optimisation of biological processes. High solids concentrations often lead to inefficient mixing conditions, which may reduce treatment capacity due to heterogeneity within the biomass.RESULTS: The hydrodynamic characteristics of a full‐scale anaerobic contact reactor treating evaporator condensate from a sulphite pulp mill were investigated. The methodology applied was based on the residence time distribution (RTD) technique using lithium as a tracer. Different non‐ideal hydraulic flow models were tested and the best model fitting RTD data was the Gamma distribution model with by‐pass. It was concluded that the full‐scale bioreactor presents a good degree of mixing with about 22% of non‐effective volume due to the presence of high amounts of inorganic materials.CONCLUSION: As a result of this study it was possible to both improve the full‐scale bioreactor performance and decrease the running costs by changes in the plant operation strategies which allowed reduction of the huge amount of inorganic materials contributing to the non‐effective volume. The methodology is simple and results from a unique RTD experiment and confirms the importance of considering mixing characteristics when assessing complex full‐scale treatment processes. Copyright © 2009 Society of Chemical Industry
In situ TEM observation of magnetic materials
Authors: Tanase Mihaela , Petford‐Long Amanda K. 
Published: January 2009

AbstractMagnetic nanostructures and thin films display novel magnetization reversal behavior as a function of size and shape, which makes them appropriate for a range of technological applications. The spatial resolution of in situ transmission electron microscopy techniques such as Lorentz TEM (LTEM) and off‐axis electron holography are well suited to analysis of the magnetic domain structure and magnetization behavior of these magnetic nanostructures and thin films. In this article the various techniques that are applicable are described, including the qualitative LTEM imaging modes and the differential phase contrast technique. In addition, quantitative methods for mapping the magnetic induction via phase reconstruction are discussed. In each case the advantages and limitations are presented. Application of the techniques to various types of magnetic structures is then presented, and the article ends with a short summary and a discussion of future developments in this field. Microsc. Res. Tech., 2009. Published 2009 Wiley‐Liss, Inc.