bluuebunny/crossref_metadata_2025 huggingface dataset:
A computer program (WDTSRP) designed for computation of sand drift potential (DP) and plotting sand roses
Authors: Saqqa W. A. , Saqqa A. W.
Published: November 2006

Wind Data Tabulator and Sand Rose Plotter (WDTSRP) is an interactive developed computer program accessible for estimating sand transport potential by winds in barren sandy deserts. The Fryberger (1979) formula for determining sand drift potential (DP) was adopted to create and develop the computer program. WDTSRP is capable of working out weighting factors (WFs), frequency of wind speed occurrence (t), drift potential (DP), resultant drift potential (RDP) and directional variability of winds (DV) and of plotting sand roses. The developed computer program is built up of a simplified system driven by a group of options and dialogue boxes that allow users to input and handle data easily and systematically. Copyright © 2006 John Wiley & Sons, Ltd.
Physical‐scale modelling of jökulhlaups (glacial outburst floods) with contrasting hydrograph shapes
Authors: Rushmer E. Lucy
Published: November 2006

Jökulhlaups (glacial outburst floods) are hazards in many glaciated environments. Jökulhlaups generated by different trigger mechanisms have different hydrograph shapes. Field evidence indicates that jökulhlaups with different hydrograph shapes produce different impacts. However, little attention has been paid to understanding the controls on jökulhlaups with differing hydrograph shapes and their subsequent impacts. Historically, flume studies have been used to investigate fluvial processes under controlled laboratory conditions. Nevertheless, few flume studies have replicated scaled hydrographs, and none have attempted to model field jökulhlaups. This study documents the technical procedure by which field prototype jökulhlaups were replicated using physical‐scale modelling techniques: an ‘exponentially rising’ jökulhlaup characterized by a prolonged rising stage and a rapid falling stage, and a ‘linearly rising’ jökulhlaup characterized by a rapid rising stage and a prolonged falling stage. The parameters of water discharge, time, discharge acceleration and deceleration rate, sediment size and sediment discharge were scaled to a 1:20 ratio.

Better‐sorted sediment, more uniform downstream sediment thickness and more gradual aggradation and deposition rates resulted from the prolonged rising stage of the exponentially rising hydrograph. More time was available during the prolonged rising stage of the exponentially rising hydrograph for bedload sheets to migrate, and for sand ripples to develop. Rapid rising stage deposition during the linearly rising hydrograph produced thick proximal deposits, limited bedload sheet migration, massive sand sheets and structureless and poorly sorted sediments. During the prolonged falling of the linearly rising hydrograph, sufficient time was available to support sand ripple development.

The study highlights that jökulhlaup hydrograph shape is important for controlling rates of sediment acquisition, transport, deposition, erosion and bedform development. The outcomes of these experimental investigations indicate that modelling of high magnitude floods is feasible in a laboratory flume. This technical approach has proved very beneficial for developing a greater understanding of flood impacts and the processes that operate during jökulhlaups. Copyright © 2006 John Wiley & Sons, Ltd.
The (Epi)genetics of human synovial sarcoma
Authors: de Bruijn Diederik R. H. , Nap Jan‐Peter , van Kessel Ad Geurts
Published: November 2006

Human synovial sarcomas are aggressive soft tissue tumors with relatively high rates of recurrences and metastases. They display a variable response to common treatment protocols such as radiation and chemotherapy. For the development of novel diagnostic, prognostic, and therapeutic approaches, detailed information on the molecular mechanisms underlying the development of these tumors is of imperative importance. Fusion of the SS18 and (one of the) SSX genes is a molecular hallmark of human synovial sarcomas. The SS18 and SSX genes encode nuclear proteins that exhibit opposite transcription regulatory activities, likely through epigenetic mechanisms. The SS18 protein functions as a transcriptional coactivator and interacts directly with members of the epigenetic chromatin remodeling and modification machineries. In contrast, the SSX proteins function as transcriptional corepressors and are associated with several Polycomb group proteins. Since the domains involved in these apparently opposite transcription regulatory activities are retained in the SS18–SSX fusion proteins, we hypothesize that these fusion proteins function as “activator–repressors” of transcription. The implications of this model for human synovial sarcoma development and future treatment are discussed. © 2006 Wiley‐Liss, Inc.
Antitumor efficacy and local distribution of doxorubicin via intratumoral delivery from polymer millirods
Authors: Weinberg Brent D. , Ai Hua , Blanco Elvin , Anderson James M. , Gao Jinming
Published: November 2006

The purpose of this study was to evaluate the antitumor efficacy and local drug distribution from doxorubicin‐containing poly(D,L‐lactide‐co‐glycolide) (PLGA) implants for intratumoral treatment of liver cancer in a rabbit model. Cylindrical polymer millirods (length 8 mm, diameter 1.5 mm) were produced using 65% PLGA, 21.5% NaCl, and 13.5% doxorubicin. These implants were placed in the center of VX2 liver tumors (n = 16, ˜8 mm in diameter) in rabbits. Tumors were removed 4 and 8 days after millirod implantation, and antitumor efficacy was assessed using tumor size measurements, tumor histology, and fluorescent measurement of drug distribution. The treated tumors were smaller than the untreated controls on both day 4 (0.17 ± 0.06 vs. 0.31 ± 0.08 cm2, p = 0.048) and day 8 (0.14 ± 0.04 vs. 1.8 ± 0.8 cm2, p = 0.025). Drug distribution profiles demonstrated high doxorubicin concentrations (>1000 μg/g) at the tumor core at both time points and drug penetration distances of 2.8 and 1.3 mm on day 4 and 8, respectively. Histological examination confirmed necrosis throughout the tumor tissue. Biodegradable polymer millirods successfully treated the primary tumor mass by providing high doxorubicin concentrations to the tumor tissue over an eight day period. © 2006 Wiley Periodicals, Inc. J Biomed Mater Res 2007
Microscopic analysis of subcutaneous reactions to endodontic sealer implants in rats
Authors: Batista Renata F.C. , Hidalgo Miriam M. , Hernandes Luzmarina , Consolaro Alberto , Velloso Tânia R.G. , Cuman Roberto K.N. , Caparroz‐Assef Silvana M. , Bersani‐Amado Ciomar A.
Published: November 2006

The reaction of subcutaneous tissues to Endofill®, Endomethasone®, Sealer 26®, and AH‐Plus® was investigated microscopically after implantation of in rats polyethylene cannulae, obturated with gutta‐percha cones and sealers, in rats. Empty polyethylene cannulae and cannulae filled with gutta‐percha cones alone were used as controls. The inflammatory reactions caused by the sealers were evaluated 7, 14, and 30 days after implantation using a descriptive, histopathological analysis. Inflammatory reactions at each implant site were gauged as either absent, discreet, moderate, or intense, and scores from 0 to 3 were attributed, respectively. Microscopic analysis revealed that Endomethasone showed the best biological behavior for all postimplant periods, followed by Sealer 26 and AH Plus, which produced an irritating effect only during the initial pos‐implant period. Endofill caused the severest irritation, producing an inflammatory reaction that ranged from moderate to intense over the entire experimental period. Reactions were more intense near those parts of the cannulae containing more sealer. These results reveal that the root canal sealers tested cause inflammation in rat, subcutaneous conjunctive tissue, the intensity of which may be related to the type and quantity of sealer used, and to postimplant period. © 2006 Wiley Periodicals, Inc. J Biomed Mater Res 2007
Synthesis of novel cholic acid functionalized branched oligo/poly(ε‐caprolactone)s for biomedical applications
Authors: Fu Hui‐Li , Yu Lan , Zhang Hua , Zhang Xian‐Zheng , Cheng Si‐Xue , Zhuo Ren‐Xi
Published: November 2006

Novel cholic acid functionalized branched oligo/poly(ε‐caprolactone)s were synthesized through the ring‐opening polymerization of ε‐caprolactone initiated by cholic acid with hydroxyl groups. The molecular weight of the branched polymers can be adjusted by controlling the feed ratio of the initiator cholic acid to the monomer ε‐caprolactone. Comparing with linear homopolymer poly(ϵ‐caprolactone) (PCL), these branched oligo/poly(ε‐caprolactone)s show much faster hydrolytic degradation rates, implies that our approach provides a convenient and effective strategy to accelerate degradation of the biodegradable polymers with slow degradation rates such as PCL. The cell culture experiment indicates the incorporation of cholic acid moiety to the polymer chain can improve both cell adherence and proliferation obviously. © 2006 Wiley Periodicals, Inc. J Biomed Mater Res 2007
Effects of coumestrol on neonatal and adult mice osteoblasts activities
Authors: Sun Jui‐Sheng , Li Ya‐Ying , Liu Man‐Hai , Sheu Shiow‐Yunn
Published: November 2006

Estrogen replacement therapy has been shown to reduce postmenopausal osteoporosis. In the present study, we examined the effects of the phytoestrogen coumestrol on neonatal and adult osteoblasts metabolism. Two different sources of osteoblast cells (neonatal mice calvaria and adult mice long bone) cultures were used in this study. The effects of coumestrol on the cellular activities were analyzed by the mitochondrial tetrazolium (MTT) assay, secretion of alkaline phosphatase (ALP), intracellular calcium content (Ca), and the gene expression of bone matrix protein, estrogen receptors (ER‐α, ER‐β), and osteoprotegerin (OPG) and osteoprotegerin ligand (OPGL). The results showed that the proliferation of neonatal mice osteoblast cells was enhanced by treatment of coumestrol. In the presence of 10−9M coumestrol, the osteoblast proliferation attained 139.5% of the control and that the coumestrol can increase the intracellular calcium contents. Type I collagen gene expression was upregulated 167% at the 1st day's culture; ALP gene expression was upregulated 360% at the 7th day's culture; while the osteocalcin gene expression was upregulated 222% at the 14th day's culture. When adult mice osteoblasts were cultured in the presence of 10−9M coumestrol, the osteoblasts population increased significantly earlier and attained its maximal effect at the 21st day's culture with 207.4% of control group. The content of ER‐β and osteoprotegerin secretion by neonatal mice control cells gradually increased during osteoblasts differentiation, whereas the ER‐α and OPGL content were decreased in this study. The cellular responses to the estradiol and counmestrol were quite different in the osteoblasts derived from different age. © 2006 Wiley Periodicals, Inc. J Biomed Mater Res 2007
Bioactive glass as precursor of designed‐architecture scaffolds for tissue engineering
Authors: Padilla S. , Sánchez‐Salcedo S. , Vallet‐Regí M.
Published: November 2006

In this work, the conditions to obtain concentrated and fluid suspensions from a bioactive glass (55‐SiO2; 41‐CaO; 4‐P2O5; mol %) were investigated. The influence of the heat treatment of the glass on the specific surface area, solubility, bioactivity, and finally on their dispersion characteristics was studied. Zeta potential and viscosity measurements were carried out, and based on the obtained results, the best dispersant was selected. The optimum concentration of dispersant, maximum content of solid and time of mixing were also investigated. Slurries containing 50 vol % could be obtained calcining the glass at 1100°C and using Darvan 811 (sodium polyacrylate) as dispersant. Scaffolds with designed architecture were prepared from these suspensions combining the gelcasting method and the stereolithography technique. A polymeric negative (replica of the desired structure) was previously obtained by stereolithography. The slurry was cast into the molds and then polymerized (gelcasting method). The negative was eliminated by heat treatment. After sintering at 1300°C, scaffolds with interconnected porosity and three‐dimensional channels of 400–470 μm and macropores of 1.4 μm were obtained. © 2006 Wiley Periodicals, Inc. J Biomed Mater Res 2007
Novel transparent nano‐ to micro‐heterogeneous substrates for in‐situ cell migration study
Authors: Tsai Irene Y. , Green J. Angelo , Kimura Masahiro , Jacobson Bruce , Russell Thomas P.
Published: November 2006

Transparent substrates having heterogeneities ranging from nanometer to micrometer lateral length scale were fabricated to study cell migration. The surfaces were generated using thin films of block copolymers and homopolymer blends on ultra smooth transparent polyethylene terephthalate films. Results show that the lateral size scale of the surface heterogeneities affects fibroblast (NIH‐3T3) adhesion, spreading and motility. More specifically, fibroblasts migrate faster on micron‐sized than on nanometer‐sized heterogeneities. Cell movements and morphology on the micron patterned surfaces resemble cells cultured in a 3D environment. These surfaces, therefore, can potentially be utilized as models to study cell behavior in physiologically relevant conditions which can add to our fundamental understanding of cell‐substrate interactions and facilitate development of surfaces for medical devices. © 2006 Wiley Periodicals, Inc. J Biomed Mater Res 2007
Contrasting effects of collagen and bFGF‐2 on neural cell function in degradable synthetic PEG hydrogels
Authors: Mahoney Melissa J. , Anseth Kristi S.
Published: November 2006

Injectable biodegradable cell carriers provide a potential means to improve transplanted cell viability in the nervous system by providing physical protection from compaction, shear forces, and the acute inflammatory response that occurs following transplantation into the host brain environment. Synthetic polyethylene glycol (PEG) hydrogels are ideal candidates for this purpose, as the degradation profile and mechanical properties of the gel can be controlled. Here we introduce biological components into the synthetic gel with the goal of improving neural cell function in the inert PEG environment. In this study, it was found that (1) bFGF‐2 is a survival/mitogenic factor for neural precursor cells in degradable hydrogel cultures, (2) collagen has no measurable effect on cell survival, metabolic activity, or proliferation, and (3) co‐application of collagen and bFGF‐2 to hydrogel cultures targets cell survival and metabolic activity, an effect that is different than either applied individually. Because collagen and bFGF‐2 support the survival and growth of neural cells and other cell types, the co‐encapsulation approach and functional characterization described in this study can be extended to the development of an array of tissue engineering applications. These findings suggest the importance of understanding and developing strategies to control the chemical microenvironment surrounding cells in three‐dimensional biomaterials. © 2006 Wiley Periodicals, Inc. J Biomed Mater Res 2007
Chemical profile of adhesive/caries‐affected dentin interfaces using Raman microspectroscopy
Authors: Wang Yong , Spencer Paulette , Walker Mary P.
Published: November 2006

In clinical practice, dentists must frequently bond adhesives to caries‐affected dentin substrates, but the bond that characteristically forms with these substrates does not provide the durability necessary for long‐term clinical function. The purpose of this study was to characterize and compare the interfacial chemistry of adhesive with caries‐affected and noncarious dentin using micro‐Raman spectroscopy. The results indicated that the differences in the Raman spectra between noncarious and caries‐affected dentin could not be accounted for by simple decreased mineralization. Both the structure of collagen and mineral in the caries‐affected dentin has been altered by the caries process. The differences in structure and composition not only interfered with acid‐etching process but also subsequent resin monomer penetration. It was shown that the interface between the adhesive and caries‐affected dentin was wider and more complicated than that of the adhesive and noncarious dentin. As a result of adhesive phase separation, a structurally integrated hybrid layer did not form at the interface with either caries‐affected or noncarious dentin. Using chemical imaging techniques, this study provides the direct evidence of adhesive phase separation at the interface with caries‐affected dentin. Although our group previously reported adhesive phase separation at the interface with noncarious dentin, the chemistry of caries‐affected dentin leads to greater variability and a more highly irregular composition along the length and breadth of the interface. © 2006 Wiley Periodicals, Inc. J Biomed Mater Res 2007
Distinctin improves the efficacies of glycopeptides and betalactams against staphylococcal biofilm in an experimental model of central venous catheter infection
Authors: Giacometti Andrea , Cirioni Oscar , Ghiselli Roberto , Orlando Fiorenza , Silvestri Carmela , Renzone Giovanni , Testa Irma , Mocchegiani Federico , Vittoria Agnese Della , Saba Vittorio , Scaloni Andrea , Scalise Giorgio
Published: November 2006

The ability of microorganisms to adhere to medical implants is a problem of high visibility and has been focused in numerous investigations. To assess the efficacy of distinctin and conventional antibiotics in the treatment of central venous catheter in vitro and in vivo studies were performed. The in vitro susceptibility assay was performed against S. aureus biofilms developed on 96‐well polystyrene tissue culture plates. Efficacy studies were performed in a rat model of CVC infection. Twenty‐four hours after implantation, the catheters were filled with distinctin. Thirty minutes later, rats were challenged via the CVC with S. aureus. Administration of antibiotics into the CVC at a concentration equal to the MBC for adherent cells, or at 1024 μg/mL began 24 h later. The killing activities of all antibiotics against adherent bacteria were at least four‐ to eightfold lower than against freely growing cells. When antibiotics were used in distinctin pretreated wells, they showed a significant increase of activity. The in vivo studies showed that when CVCs were pretreated with distinctin biofilm bacterial load was further decreased to 101 CFU/mL and bacteremia was not detected. Distinctin displays potential as an adjunctive agent to antibiotics in the treatment of CVC‐related infections. © 2006 Wiley Periodicals, Inc. J Biomed Mater Res 2007
Effects of a p38 MAP kinase inhibitor on bone ingrowth and tissue differentiation in rabbit chambers
Authors: Goodman S.B. , Ma T. , Spanogle J. , Chiu R. , Miyanishi K. , Oh K. , Plouhar P. , Wadsworth S. , Smith R.L.
Published: November 2006

The effects of an oral p38 mitogen‐activated protein kinase (MAPK) inhibitor and polyethylene particles separately and together on tissue differentiation in the bone harvest chamber (BHC) in rabbits over a 3‐week treatment period were investigated. The harvested tissue was analyzed histomorphometrically for markers of bone formation (percentage of bone area), osteoblasts (alkaline phosphatase staining), and osteoclasts (CD51, the α chain of the vitronectin receptor). Polyethylene particles decreased the percentage of bone ingrowth and staining for alkaline phosphatase. The p38 MAPK inhibitor alone decreased alkaline phosphatase staining. When the oral p38 MAPK inhibitor was given and the chamber contained polyethylene particles, there was a suppression of bone ingrowth and alkaline phosphatase staining. In contrast to oral non‐steroidal anti‐inflammatory drugs (NSAIDs) and local Interleukin‐1 receptor antagonist (IL‐1ra) administration, the oral p38 MAPK inhibitor alone did not suppress bone formation when given during the initial phase of tissue differentiation. Particle‐induced inflammation and the foreign body reaction were not curtailed when the p38 MAPK inhibitor was given simultaneously with particles. Additional experiments are needed to establish the efficacy of p38 MAPK inhibitor administration on mitigating an established inflammatory and foreign body reaction that parallels the clinical situation more closely. © 2006 Wiley Periodicals, Inc. J Biomed Mater Res 2007
Functionalized hydrogel surfaces for the patterning of multiple biomolecules
Authors: Hynd Matthew R. , Frampton John P. , Burnham Mary‐Rose , Martin David L. , Dowell‐Mesfin Natalie M. , Turner James N. , Shain William
Published: November 2006

Patterning of multiple proteins and enzymes onto biocompatible surfaces can provide multiple signals to control cell attachment and growth. Acrylamide‐based hydrogels were photo‐polymerized in the presence of streptavidin–acrylamide, resulting in planar gel surfaces functionalized with the streptavidin protein. This surface was capable of binding biotin‐labeled biomolecules. The proteins fibronectin and laminin, the enzyme alkaline phosphatase, and the photo‐protein R‐phycoerythrin were patterned using soft lithographic techniques. Polydimethylsiloxane stamps were used to transfer biotinylated proteins onto streptavidin‐conjugated hydrogel surfaces. Stamped biomolecules were spatially resolved to feature sizes of 10 μm. Fluorescence measurements were used to assess protein transfer and enzyme functionality on modified surfaces. Our results demonstrate that hydrogel surfaces can be patterned with multiple proteins and enzymes, with retention of biological and catalytic activity. These surfaces are biocompatible and provide cues for cell attachment and growth. © 2006 Wiley Periodicals, Inc. J Biomed Mater Res 2007
Preparation and characterization of hydroxyapatite/poly(ethylene glutarate) biomaterials
Authors: Siriphannon Punnama , Monvisade Pathavuth , Jinawath Supatra , Hemachandra Khemchai
Published: November 2006

Hydroxyapatite/poly(ethylene glutarate) (HAp/PEG) biomaterial composites were prepared by ring‐opening polymerization (ROP) of cyclic oligo(ethylene glutarate) (C‐PEG) in porous HAp scaffolds. The HAp/C‐PEG precomposites were prepared by immersing the porous HAp scaffolds in the mixture solution of C‐PEG and dibutyl tinoxide catalyst overnight and polymerizing at 200°C for 24, 48, and 72 h under vacuum. The successful ROP of C‐PEG in the porous HAp scaffolds was corroborated by the signals of hydroxyl end‐group of PEG shown in the 1H NMR spectrum of the ROP‐products extracted from the composites. PEG in the composites was present as a thin layer coating on the HAp grains and was evenly distributed throughout the samples. The PEG content was about 13–16 wt % and decreased with increasing polymerization time. Its molecular weight (M̄w, weight average) measured by gel permeation chromatography was in the range of 4300–6800 g/mol. Compressive strength of the HAp/PEG composites was significantly increased from 3 MPa of the porous HAp scaffold to 11–15 MPa, depending on the PEG content in the composites. In vitro bioactivity of the HAp/PEG composites was studied by soaking in simulated body fluid (SBF) at 36.5°C for 7–28 days. After prolonged soaking, the HAp nanocrystals precipitated from the SBF solution and formed as a layer of globular aggregates, coated on the composite surfaces. This result suggested that the HAp/PEG composite was a bioactive material. © 2006 Wiley Periodicals, Inc. J Biomed Mater Res, 2007
Stability of and inflammatory response to silicon coated with a fluoroalkyl self‐assembled monolayer in the central nervous system
Authors: Wang Anfeng , Liang Xuemei , McAllister II James P. , Li Jie , Brabant Kelley , Black Carolyn , Finlayson Paul , Cao Ting , Tang Haiying , Salley Steven O. , Auner Gregory W. , Simon Ng K.Y.
Published: November 2006

A self‐assembled monolayer (SAM) of fluoroalkyl silane (FAS) (CF3(CF2)5(CH2)2SiCl3) was deposited on the surface of silicon wafers, aiming to enhance its stability and to reduce the inflammatory response in the central nervous system. Following implantation of the FAS SAM coated silicon in rat brains, the FAS SAM coating failed to reduce the inflammatory response of silicon, because it could not prevent the corrosion of the underlying silicon. The corrosion was hindered for the initial 10 days by the FAS SAM coating, but there was nearly no difference when compared to the uncoated silicon when the implantation periods were extended to 28 and 90 days. The FAS SAM coating was completely removed within 28 and 90 days. Meanwhile, on all the extracted uncoated and FAS SAM coated silicon wafers, there were proteinaceous substances deposited on the surfaces, and the amount of the deposits increased with exposure time. © 2006 Wiley Periodicals, Inc. J Biomed Mater Res, 2007
Biomedical coatings based on chitin soluble extract for inhibition of fungal adhesion to polymeric surfaces
Authors: Zilberman Meital , Navon Alon , Sandovsky‐Losica Hana , Segal Esther
Published: November 2006

Indwelling medical devices made of polymeric materials, such as intravenous (IV) catheters, are known risk factors for development of fungal infection, particularly systemic candidiasis, that are a significant cause of morbidity and lethality in compromised patients. Candida can form a biofilm on the polymeric surface, serving as a nidus for systemic, difficult to eradicate infection. The current research focuses on development and study of a chitin soluble extract (CSE) coating on polyurethane (PU), in order to reduce the level of adherence of C. albicans to the PU surface. The immobilization of CSE onto the PU surface was performed using both, chemical binding and physical adsorption. Our results indicate that CSE develops a unique tertiary structure in which basic elements in the range of 100 nm build “fingers” and these “fingers” are arranged in a concentric structure around a center. The CSE coated films showed 75% inhibition of C. albicans adhesion for the chemical binding and 83% for the physical adsorption coating and even after 11 weeks the inhibitory effect on adhesion is still significant. Hence, our new coatings may lead to a new generation of medical devices with surfaces that can prevent fungal adhesion. © 2006 Wiley Periodicals, Inc. J Biomed Mater Res, 2007
Hybrid composites of calcium phosphate granules, fibrin glue, and bone marrow for skeletal repair
Authors: Le Nihouannen Damien , Goyenvalle Eric , Aguado Eric , Pilet Paul , Bilban Melitta , Daculsi Guy , Layrolle Pierre
Published: November 2006

Synthetic bone substitutes, such as calcium phosphate ceramics, give good results in clinical applications. In order to adapt to surgical sites, bioceramics come in the form of blocks or granules, and are either dense or porous. Combining these bioceramics with fibrin glue provides a mouldable and self‐hardening composite biomaterial with the biochemical properties of each component. Critical‐sized defects in the femoral condyle of rabbits were filled with TricOs/fibrin glue/bone marrow hybrid/composite material. The TricOs granules (1–2 mm) were composed of hydroxyapatite and beta tricalcium phosphate (60/40 in weight). The fibrin glue was composed of fibrinogen, thrombin and other biological factors and mixed with MBCP granules either simultaneously or sequentially. Bone marrow was also added to the MBCP/fibrin composite prior to filling the defects. After 3, 6, 12, and 24 weeks of implantation, the newly‐formed bone was analysed with histology, histomorphometry and mechanical tests. The newly‐formed bone had grown centripetally. Simultaneous application of fibrin glue showed better results for mechanical properties than sequential application after 6 weeks. Around 40% of bone had formed after 24 weeks in the three groups. Although the addition of bone marrow did not improve bone formation, the MBCP/fibrin material could be used in clinical bone filling applications. © 2006 Wiley Periodicals, Inc. J Biomed Mater Res, 2007
Fabrication and characterization of a novel composite PNIPAAm hydrogel for controlled drug release
Authors: Xu Xiao‐Ding , Wei Hua , Zhang Xian‐Zheng , Cheng Si‐Xue , Zhuo Ren‐Xi
Published: November 2006

Novel composite poly(N‐isopropylacrylamide) (PNIPAAm) hydrogels, containing poly(N‐isopropylacrylamide)‐block‐poly(methyl methacrylate) (PNIPAAm‐b‐PMMA) micelles for sustained drug delivery were prepared and characterized. Various amounts of thermal sensitive PNIPAAm‐b‐PMMA micelles were incorporated physically into thermosensitive PNIPAAm bulk hydrogel to form composite PNIPAAm hydrogels. The resultant composite hydrogels were characterized by scanning electron microscopy (SEM) and differential scanning calorimetry (DSC) for morphological and thermal properties, respectively. The temperature dependence of swelling ratio and response kinetics upon heating or cooling were also investigated to understand the smart properties, that is, temperature‐sensitive properties of the composite PNIPAAm hydrogels. These composite PNIPAAm hydrogels exhibited a faster shrinking kinetics than the one of pure PNIPAAm hydrogels. In addition, prednisone acetate, used as model drug, was loaded into the micelles incorporated to the composite PNIPAAm hydrogels. The controlled release behavior of the novel composite PNIPAAm hydrogels at different temperatures (22 and 37°C) was examined. © 2006 Wiley Periodicals, Inc. J Biomed Mater Res, 2007
A novel methodology for imaging new bone formation around bioceramic bone substitutes
Authors: Gorustovich Alejandro A. , Sivak Matías G. , Guglielmotti María B.
Published: November 2006

In this study, Frost's bulk‐staining in combination with confocal laser scanning microscopy (CLSM) was used to image and characterize ground sections of undecalcified rat bone tissue with in situ bioceramic implants. This was addressed by bulk staining specimens in alcohol‐soluble basic fuchsin dye. The ground sections were imaged using CLSM in the confocal fluorescence mode. Confocal images revealed that the newly formed bone could be clearly distinguished from bone marrow and cortical bone, as well as from the implant material. © 2006 Wiley Periodicals, Inc. J Biomed Mater Res, 2007
Quantification of various growth factors in different demineralized bone matrix preparations
Authors: Wildemann B. , Kadow‐Romacker A. , Haas N.P. , Schmidmaier G.
Published: November 2006

Besides autografts, allografts, and synthetic materials, demineralized bone matrix (DBM) is used for bone defect filling and treatment of non‐unions. Different DBM formulations are introduced in clinic since years. However, little is known about the presents and quantities of growth factors in DBM. Aim of the present study was the quantification of eight growth factors important for bone healing in three different “off the shelf” DBM formulations, which are already in human use: DBX putty, Grafton DBM putty, and AlloMatrix putty. All three DBM formulations are produced from human donor tissue but they differ in the substitutes added. From each of the three products 10 different lots were analyzed. Protein was extracted from the samples with Guanidine HCL/EDTA method and human ELISA kits were used for growth factor quantification. Differences between the three different products were seen in total protein contend and the absolute growth factor values but also a large variability between the different lots was found. The order of the growth factors, however, is almost comparable between the materials. In the three investigated materials FGF basic and BMP‐4 were not detectable in any analyzed sample. BMP‐2 revealed the highest concentration extractable from the samples with ∼3.6 μg/g tissue without a significant difference between the three DBM formulations. In DBX putty significantly more TGF‐β1 and FGFa were measurable compared to the two other DBMs. IGF‐I revealed the significantly highest value in the AlloMatrix and PDGF in Grafton. No differences were accessed for VEGF. Due to the differences in the growth factor concentration between the individual samples, independently from the product formulation, further analyzes are required to optimize the clinical outcome of the used demineralized bone matrix. © 2006 Wiley Periodicals, Inc. J Biomed Mater Res, 2007
Histological findings of long‐term healing of the experimental defects by application of a synthetic biphasic ceramic in rats
Authors: Develioglu Hakan , Saraydin Serpil Ünver , Dupoirieux Laurent , Sahin Zeynep Deniz
Published: November 2006

Calcium phosphate ceramics are generally biocompatible and can develop interactions with human recipient bone. Therefore, they can be widely used in the field of periodontology and dentistry. The purpose of this investigation was to assess the long‐term histological bone healing results of experimentally created critical size parietal bone defects in rats. Twelve Wistar rats were used in this investigation. Two 6‐mm wide, symmetrical, and circular critical size defects were created in each parietal bone of the animals. While the right defects filled with granular implant (Ceraform®), the symmetrical defects were taken as controls. Eighteen months after implantation, rats were killed and defects including the biomaterial with surrounding bone was taken for histological examination. Serial histological sections were cut across the defects and stained for the histological analysis. Both control and Ceraform implanted regions contained dense collagenous tissue. In the implantation site, multinuclear giant cells were observed around the material. On the other hand, there were no necrosis, tumour, and infection in the implantation region. There was no statistical difference between the control and ceraform implanted groups when the bone formation results were compared (p > 0.05). In conclusion, the results revealed that this material is biocompatible and does enhance the new bone building despite the long‐term observation period. Although this biphasic ceramic shows within the limits of the study as a less resorptive and not osteoconductive properties, it can be considered as a biocompatible bone defect filling material having a limited application alternative in dentistry and medicine. © 2006 Wiley Periodicals, Inc. J BiomedMater Res 2007
The role of MAPK in Kupffer cell toll‐like receptor (TLR) 2‐, TLR4‐, and TLR9‐mediated signaling following trauma‐hemorrhage
Authors: Thobe Bjoern M. , Frink Michael , Hildebrand Frank , Schwacha Martin G. , Hubbard William J. , Choudhry Mashkoor A. , Chaudry Irshad H.
Published: November 2006

Severe injury deranges immune function and increases the risk of sepsis and multiple organ failure. Kupffer cells play a major role in mediating posttraumatic immune responses, in part via different Toll‐like receptors (TLR). Although mitogen‐activated protein kinases (MAPK) are key elements in the TLR signaling pathway, it remains unclear whether the activation of different MAPK are TLR specific. Male C3H/HeN mice underwent midline laparotomy (i.e., soft tissue injury), hemorrhagic shock (MAP ∼35 mm Hg for 90 min), and resuscitation. Kupffer cells were isolated 2 h thereafter, lysed and immunoblotted with antibodies to p38, ERK1/2, or JNK proteins. In addition, cells were preincubated with specific inhibitors of p38, ERK1/2, or JNK MAPK followed by stimulation with the TLR2 agonist, zymosan; the TLR4 agonist, LPS; or the TLR9 agonist, CpG DNA. Cytokine (TNF‐α, interleukin‐6 (IL‐6), monocyte chemoattractant protein‐1 (MCP‐1), and KC) production was determined by cytometric bead array after 24 h in culture. MAPK activity as well as TNF‐α, MCP‐1, and KC production by Kupffer cells were significantly increased following trauma‐hemorrhage. TLR4 activation by LPS stimulation increased the levels of all measured cytokines. CpG‐stimulated TLR9 signaling increased TNF‐α and IL‐6 levels; however, it had no effect on chemokine production. Selective MAPK inhibition demonstrated that chemokine production was mediated via p38 and JNK MAPK activation in TLR2, ‐4, and ‐9 signaling. In contrast, TNF‐α and IL‐6 production was differentially regulated by MAPK depending on the TLR pathway stimulated. Thus, Kupffer cell TLR signaling employs different MAPK pathways in eliciting cytokine and chemokine responses following trauma‐hemorrhage. J. Cell. Physiol. 210: 667–675, 2007. © 2006 Wiley‐Liss, Inc.
Corticotropin releasing factor receptor 1 (CRF1) and CRF2agonists exert an anti‐inflammatory effect during the early phase of inflammation suppressing LPS‐induced TNF‐α release from macrophages via induction of COX‐2 and PGE2
Authors: Tsatsanis Christos , Androulidaki Ariadne , Dermitzaki Erini , Gravanis Achille , Margioris Andrew N.
Published: November 2006

Corticotropin‐releasing factor (CRF), the principal regulator of the hypothalamus‐pituitary‐adrenal (HPA) axis, also modulates the inflammatory response directly, via its effect on mast cells and macrophages. On macrophages, it augments production of lipopolysaccharide (LPS)‐induced pro‐inflammatory cytokines. CRF and its related peptides may also act as anti‐inflammatory agents. Aim of the present work was to examine the role of macrophages on the anti‐inflammatory effects of CRF‐peptides and the mechanism involved. Thus, we examined if CRF receptor 1 (CRF1) and CRF2agonists exert any anti‐inflammatory effect on primary mouse macrophages. We have found that: (a) CRF, Urocortin (UCN)1 and UCN2 transiently suppressed the release of Tumor Necrosis Factor‐alpha (TNF‐α) in LPS‐activated macrophages, an effect peaking at 4 h. This effect did not involve changes on TNF‐α transcription. (b) CRF peptide‐induced suppression of TNF‐α release depended on induction of COX‐2 and PGE2 synthesis. (c) Use of specific CRF1and CRF2antagonists suggested that this effect involved both CRF receptor types. (d) The effect of CRF‐peptides on COX‐2 was mediated via PI3K and p38MAPK. (e) Longer exposure of macrophages to CRF‐peptides resulted in induction of TNF‐α production via enhancement of its transcription. In conclusion, this is the first report suggesting that CRF1and CRF2agonists exert a biphasic effect on macrophages. During the early stages of the inflammatory response, they suppress TNF‐α release via induction of COX‐2/PGE2 while later on they induce TNF‐α transcription. Hence, the reported anti‐inflammatory effect of CRF‐peptides appears to involve macrophages and is confined at the early stage of inflammation. J. Cell. Physiol. 210: 774–783, 2007. © 2006 Wiley‐Liss, Inc.
Eye size in geckos: Asymmetry, allometry, sexual dimorphism, and behavioral correlates
Authors: Werner Yehudah L. , Seifan Tal
Published: November 2006

The function of the vertebrate eye depends on its absolute size, and the size is presumably adapted to specific needs. We studied the variation of eye size at all levels, from intra‐individual to inter‐specific, in lid‐ less, spectacled, gecko lizards (Gekkonomorpha). We mea sured 1,408 museum specimens of 62 species, representing subfamilies Diplodactylinae, Gekkoninae, and Sphaerodactylinae. Intra‐individually, eye size showed significant directional asymmetry in Stenodactylus sthenodactylus. A latitudinal study of six species confirmed that during postnatal ontogeny eye size undergoes conventional negative allometry; the slope is steeper among adults than among juveniles, expressing the need of juveniles for relatively larger eyes. Within species with sexual size dimorphism, commonly the larger sex possessed larger eyes in absolute terms but not relative to head‐and‐body length. Interspecifically, eye size showed negative allometry, with slope significantly steeper than those of intraspecific ontogenetic allometry, again expressing the need of juveniles for relatively larger eyes and showing that eye‐size differences among species do not merely result from body‐size differences. Finally, adult eye size varied interspecifically in correlation with parameters of behavioral ecology: eyes were significantly larger in nocturnal than in diurnal species, and significantly larger in cursorial than in scansorial species. J. Morphol., 2006. © 2006 Wiley‐Liss, Inc.
The Loch Lomond Readvance on north Arran, Scotland: glacier reconstruction and palaeoclimatic implications
Authors: Ballantyne Colin K.
Published: November 2006

Geomorphological mapping of northern Arran provides evidence for two advances of locally nourished glaciers, the younger being attributable to the Loch Lomond Stade (LLS) of ca. 12.9–11.5 k yr BP, primarily through the mutually exclusive relationship between glacial limits and Lateglacial periglacial features. The age of the earlier advance is unknown. Inferred LLS glacier cover comprised two small icefields and eight small corrie or valley glaciers and totalled 11.1 km2. ELAs reconstructed using area–altitude balance ratio methods range from 268 m to 631 m for individual glaciers, with an area‐weighted mean ELA of 371 m. ELAs of individual glaciers are strongly related to snow‐contributing areas. The area‐weighted mean ELA is consistent with a north–south decline in LLS ELAs along the west coast of Great Britain. This decline has an average latitudinal gradient of 70 m 100 km−1, equivalent to a mean southwards ablation‐season temperature increase of ca. 0.42°C 100 km−1. Mean June–August temperatures at the regional climatic ELA, estimated from chironomid assemblages in SE Scotland, lay between 5.7 ± 0.1°C and 4.1 ± 0.2°C. Empirical relationships between temperature and precipitation at modern glacier ELAs indicate equivalent mean annual precipitation at the ELA lay between 2002 ± 490 mm and 2615 ± 449 mm. These figures suggest that stadial precipitation on Arran fell within a range between +8% and −33% of present mean annual precipitation. Copyright © 2006 John Wiley & Sons, Ltd.
Synthesis and Properties of pH‐ and Temperature‐Sensitive Poly[(N‐isopropylacrylamide)‐co‐(2‐methylenebutane‐1,4‐dioic acid)] Hydrogels
Authors: Katime Issa , Quintana José R. , Valderruten Nora E. , Cesteros Luis C.
Published: November 2006

Summary: Hydrogels of NIPA and MBDA were synthesized by free‐radical crosslinking copolymerization with different monomer ratios and with two concentrations of the crosslinking agent. The aim of this work was to study the swelling behavior of these gels that are both temperature and pH sensitive. PNIPA hydrogels are typical examples of thermo‐shrinking hydrogels with a LCST, TC, around 31–34 °C. MBDA is a weakly ionizable monomer which imparts a pH sensitiveness to the copolymer hydrogels. The pH influence on the swelling behavior of the studied hydrogels was analyzed using deionized water and aqueous HCl and NaOH as swelling media. According to the results found in deionized water, the swelling processes of P(NIPA‐MBDA) hydrogels follow second‐order kinetics at 22 and 37 °C. The equilibrium water content, W∞, and the rate constant, K, increased at greater concentrations of MBDA and decreased as the crosslinking agent concentration increased. As the MBDA content in the hydrogel increased, the collapsing of the hydrogels at higher temperatures than the LCST became of less importance. The degree of swelling of pure PNIPA hydrogels was not influenced by the pH of the swelling medium. However, this influence increased as the MBDA content increased. This was due to the fact that at low pH most of the MBDA units are in the protonated (neutral) form and at high pH in the ionized one.

Swelling isotherms of hydrogels with different copolymer compositions and with 1.5 wt.‐% of BIS at 22 °C in deionized water.

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Swelling isotherms of hydrogels with different copolymer compositions and with 1.5 wt.‐% of BIS at 22 °C in deionized water.
Characterization of Metallo‐Supramolecular Block Copolymers by Analytical Ultracentrifugation
Authors: Raşa Mircea , Lohmeijer Bas G. G. , Hofmeier Harald , Thijs Hanneke M. L. , Schubert D. , Schubert Ulrich S. , Tziatzios Christos
Published: November 2006

Summary: Applications of analytical ultracentrifugation in the field of synthetic polymers have followed a clearly increasing trend in the past few years, concerning the variety of investigated samples, experimental approaches, and methods of data analysis. We report a characterization study of two metallo‐supramolecular diblock copolymers with different block lengths and of a chain extended metallo‐supramolecular polymer. The analysis of sedimentation velocity and sedimentation equilibrium profiles was discussed in detail and the results were compared to each other, to determine the molar mass distribution and the state of association in solution. A simple method for determining the average translational diffusion coefficients is proposed and discussed relative to other methods. The average values of the molar mass and sedimentation coefficient distributions, the average friction coefficients, and size information were obtained and discussed.

c(S) analysis of SV profiles using Sedfit for the (PEG180‐[Ru2+]‐)n chain extended polymer showing the presence of several species.

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c(S) analysis of SV profiles using Sedfit for the (PEG180‐[Ru2+]‐)n chain extended polymer showing the presence of several species.
Polymerization of Styrene Sulfonate Ethyl Ester and Styrene Sulfonate Dodecyl Ester by ATRP: Synthesis and Characterization of Polymer Brushes
Authors: Lienkamp Karen , Ruthard Christian , Lieser Günter , Berger Rüdiger , Groehn Franziska , Wegner Gerhard
Published: November 2006

Summary: Cylindrical polymer brushes from PSSE and PSSD have been synthesized by a ‘grafting from’ approach by ATRP in solution. Starting from macroinitiators with 570 and 1 600 repeat units, and 10–100% reactive site density, PSSD brushes with 10–40% grafting density and PSSE brushes with 10–100% grafting density are obtained. The brushes have been characterized by 1H NMR spectroscopy, GPC‐MALLS, analytical ultracentrifugation, AFM, and TEM.

Phase AFM image of a PSSD brush. The image was obtained using a ‘supercantilever’ (tapping mode, mica).

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Phase AFM image of a PSSD brush. The image was obtained using a ‘supercantilever’ (tapping mode, mica).
Synthesis and Characterization of Supramolecular Polymeric Materials Containing Azopyridine Units
Authors: Millaruelo Marta , Chinelatto Luiz S. , Oriol Luis , Piñol Milagros , Serrano Jose‐Luis , Tejedor Rosa M.
Published: November 2006

Summary: The synthesis and characterization of a series of supramolecular polymeric complexes formed by H‐bonding interactions between benzoic acid and azopyridine derivatives are described. A series of polymeric networks have been synthesized using a polymethacrylate bearing benzoic acid units as side groups, and several polymers with azopyridine as H‐acceptor side groups. Furthermore, low‐molecular‐weight pyridine derivatives have been used to prepare an homologous side‐chain polymer, and a network with azopyridine as a non‐covalent crosslinker. Special attention was paid to the thermal and mesomorphic properties of these materials, which were studied by DSC, POM, and XRD.

Micrograph of the mesomorphic melt of a sample taken at 130 °C on cooling from the isotropic state.

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Micrograph of the mesomorphic melt of a sample taken at 130 °C on cooling from the isotropic state.