bluuebunny/crossref_metadata_2025_split huggingface dataset:
Interaction of antithrombin III with surface‐immobilized albumin—heparin conjugates
Authors: van Delden C. J. , Engbers G. H. M. , Feijen Jan 
Published: May 2005

AbstractThe interaction between antithrombin III (ATIII) and albumin–heparin conjugates covalently coupled onto carboxylated polystyrene beads either in buffer containing albumin or in plasma was studied using 14C‐labeled ATIII. Binding isotherms of ATIII were modeled using a summation of two Langmuir equations. These equations describe the binding of ATIII to two different sets of binding sites, one with a high, the other with a low affinity for ATIII. The average binding constants for the binding of ATIII to these sites are 9 × 106 L/mol and 0.3 × 106 L/mol, respectively. The binding of ATIII to surface binding sites with a high affinity for ATIII was correlated with the presence of specific ATIII binding sites in the immobilized heparin. Binding of ATIII from albumin solutions to binding sites with a low affinity for ATIII was dominated by nonspecific binding of ATIII to the immobilized heparin. A third small fraction of the surface bound ATIII is probably adsorbed to sites on the surface not covered with heparin. In the case of the binding of ATIII to the heparinized surface from plasma solutions, a fraction of initially adsorbed ATIII was desorbed by other plasma proteins. This desorption in combination with direct competition between ATIII and other plasma proteins resulted in lower ATIII surface concentrations using plasma as compared to the ATIII surface concentrations obtained using albumin solutions. The binding of ATIII to nonspecific binding sites was almost completely inhibited in the presence of plasma proteins. The amount of ATIII bound to immobilized heparin via specific ATIII binding sites was 30% lower in plasma solutions as compared to the specific binding of ATIII using albumin solutions. It is concluded that the accessibility of immobilized heparin for ATIII in plasma decreases by binding of heparin–binding proteins onto the immobilized heparin and/or by adsorption of other plasma proteins on the heparinized surface. © 1995 John Wiley & Sons, Inc.
The rat epididymal fat pad as an implantation site for the study of microcapsule biocompatibility: Validation of the method
Authors: Pariseau Jean‐François , Leblond François A. , Harel François , Lepage Yves , Hallé Jean‐Pierre 
Published: May 2005

AbstractThe study of microcapsule biocompatibility is hindered by their uneven distribution and low recovery when implanted into the peritoneum. We evaluated the use of the rat epididymal fat pad as a microcapsule implantation site for biocompatibility studies. The recovery rate of microcapsules containing 85Sr‐labeled microspheres was 99.6 ± 0.75%. Microcapsules, made from the same batch of nonpurified alginate, were injected into both fat pads of male Lewis rats (n = 18) and retrieved 14 days later. A semiquantitative fibrosis score scaled from 0 to 3.0 showed that the pericapsular reaction was uniform throughout a fat pad, and that the results of the two fat pads were equivalent because the null hypothesis of inequivalence was rejected (P < .001). Thus, this method can be used to compare the biocompatibility of microcapsule of differing compositions. © 1995 John Wiley & Sons, Inc.
Evaluation of poly(DTH carbonate), a tyrosine‐derived degradable polymer, for orthopedic applications
Authors: Ertel Sylvie I. , Kohn Joachim , Zimmerman Mark C. , Parsons J. Russell 
Published: May 2005

AbstractThe polymerization of desaminotyrosinetyrosylhexyl ester (DTH) with phosgene gives rise to poly(DTH carbonate), a new pseudopoly(amino acid). To evaluate the performance of this bioabsorbable material in orthopedic applications, the tissue responses elicited by compression‐molded pins of poly(DTH carbonate) and clinically used polydioxanone pins (PDS; Orthosorb®) were compared. The two types of pins were implanted in the paravertebral muscle and in the metaphyseal proximal tibia and distal femur of 10 White New Zealand Rabbits for 1, 2, 4, and 26 weeks. The tissue response was evaluated using histologic staining of softand hard‐tissue sections, fluorescent bone marker incorporation, and backscattered electron imaging. In soft tissue, both poly(DTH carbonate) and PDS elicited a mild inflammatory response resulting in encapsulation. During the disintegration phase, the PDS implants triggered a foreign body response involving the phagocytosis of polymeric debris by histiocytes and giant cells. No such response was observed for poly(DTH carbonate). In hard tissue, close bone apposition was observed throughout the 26‐week test period for poly(DTH carbonate) implants. At the 26‐week time point, the poly(DTH carbonate) implants exhibited surface erosion and were penetrated by new bone. In contrast, an intervening fibrous tissue layer was always present between the PDS pins and the bone. At 26 weeks, the PDS implants had partially resorbed and a foreign body response characterized by infiltration of inflammatory cells, and bone resorption was observed in several of the implantation sites. This study indicates that poly(DTH carbonate) and PDS exhibit fundamentally different interactions with hard tissue, and that poly(DTH carbonate) is a promising orthopedic implant material. © 1995 John Wiley & Sons, Inc.
Effects of γ‐alumina and hydroxyapatite coatings on the growth and metabolism of human osteoblasts
Authors: Labat Béatrice , Chamson Annette , Frey Jacques 
Published: May 2005

AbstractThe behavior of human osteoblasts cultivated on hydroxyapatite or alumina‐coated disks of Ti6AL4V was studied in vitro. Cell anchorage and spreading were observed by scanning electron microscopy. Cell growth was monitored by counting cells and measuring DNA at 5 h and 2, 5, and 10 days after cell seeding. Cells grown for 10 days were labeled with 14C‐proline and total protein and collagen synthesis were measured; the type of collagen was also determined. Both ceramics showed excellent biocompatibility. At 10 days of culture the cells showed a higher rate of proliferation on alumina than on hydroxyapatite. Neither ceramic altered the collagen biosynthesis or the osteoblastlike properties of the cells, as indicated by the high percentage of type I collagen. © 1995 John Wiley & Sons, Inc.
Regeneration of full‐thickness wounds using collagen split grafts
Authors: van Luyn M. J. A. , Verheul J. , van Wachem P. B. 
Published: May 2005

AbstractCollagen‐based skin substitutes are among the most promising materials to improve regeneration of full‐thickness wounds. However, additional meshed grafts or cultured epidermal grafts are still required to create epidermal regeneration. To avoid this, we substituted collagen‐based split grafts, i.e., grafts with a separated top and bottom layer, in a rat full‐thickness wound model and compared regeneration with nontreated, open control wounds. We hypothesized that epidermal regeneration would occur in the split in between the two layers, with the top layer functioning as a clot/scab and the bottom layer as a dermal substitute. Two types of dermal sheep collagen (DSC) split grafts were tested: one with a top layer of noncrosslinked DSC (NDSC) and bottom layer of hexamethylenediisocyanate crosslinked DSC (HDSC), further called N/HDSC; and the second with both a top and bottom layer of HDSC (H/HDSC). With the N/HDSC split graft NDSC did not function as a sponge for formed exudate and as a consequence the split was no longer available to facilitate epidermal regeneration. In contrast, with the H/HDSC graft the split facilitated proliferation and differentiation of the epidermal cells in the proper way. With this graft, clot formation was restricted to the top layer, which was rejected after 8 weeks, while the bottom layer functioned during gradual degradation as a temporary matrix for the formation of autologous dermal tissue. H/HDSC strongly inhibited infiltration of myofibroblasts, resulting in a 30% wound contraction, while a 100% contraction was found with the open control wound. The results show that H/HDSC split‐grafts function conforms to the hypothesis in regeneration of large, full‐thickness wounds without further addition of seeded cells or use of meshed autografts. © 1995 John Wiley & Sons, Inc.
Pyrolysis–gas chromatography of carbonate apatites used for sintering
Authors: Doi Y. , Koda T. , Adachi M. , Wakamatsu N. , Goto T. , Kamemizu H. , Moriwaki Y. , Suwa Y. 
Published: May 2005

AbstractGas chromatography was employed to quasi‐continuously determine the amount of carbon dioxide that evolved from carbonate apatite specimens during sintering. Assuming that the carbonate in the specimens decomposed to carbon dioxide on a mole‐for‐mole basis, the determination of the carbon dioxide evolved allowed for the determination of the amount of carbonate that remained in the specimens during different stages of sintering. Previously, this measurement could be carried out only after sintering was completed. Comparison of data obtained from specimens compacted isostatically at 600 MPa for sintering with powder specimens indicated that the amount of carbonate remaining in the sintered apatite mass strongly depended on heating rates, heating temperatures, and holding‐time intervals. © 1995 John Wiley & Sons, Inc.
Degradation potential of plasma‐sprayed hydroxyapatite‐coated titanium implants
Authors: Paschalis E. P. , Zhao Q. , Tucker B. E. , Mukhopadhayay S. , Bearcroft J. A. , Beals N. B. , Spector M. , Nancollas G. H. 
Published: May 2005

AbstractThe purpose of this study was to develop an analytical method for evaluating the dissolution behavior of plasmasprayed hydroxyapatite (HAP) coatings. Six commercially available and clinically used coatings applied to nonporous titanium coupons according to their respective specifications for orthopedic devices were used in this study. Dissolution behavior was monitored by first preconditioning the implant in 0.15 mol L−1 sodium chloride solution at 37°C until either equilibrium or the desired change in solution hydrogen and calcium ion concentrations had been reached. In the second step, the implants were subjected to dual constant composition (DCC) dissolution under conditions of controlled undersaturation. Results indicate that the dissolution rates of the HAP coatings may differ by as much as a factor of 5 despite the fact that analytical techniques, including X‐ray diffraction and FTIR, indicate no change in crystallinity or composition of the coatings before and after the solution treatment. These results indicate that HAP coatings from different sources react very differently when placed in the same local aqueous environment. However, more work will be necessary before these in vitro results can be used to predict in vivo behavior. © 1995 John Wiley & Sons, Inc.
Structural effect of galactose residue in synthetic glycoconjugates on interaction with rat hepatocytes
Authors: Yura Hirofumi , Goto Mitsuaki , Okazaki Hidemi , Kobayashi Kazukiyo , Akaike Toshihiro 
Published: May 2005

AbstractN‐p‐Vinylbenzyl‐O‐β‐D‐galactopyranosyl‐(1,4)‐D‐gluconamide (PVLA) has been used as an asialoglycoprotein model polymer. Rat hepatocytes expressing asialoglycoprotein receptors are capable of binding to hydrophobic plastic dishes coated with PVLA. PVLA, water‐soluble polystyrene derivatives bearing galactose residues preferentially adsorb to plastic plates made of polystyrene rather than those of poly(methyl methacrylate). Hence, we modified chitosan beads with linear chains composed of a long alkyl or phenyl moiety to study the effect of structural variations of adsorbed PVLA, and investigated the extent of hepatocyte attachment to the hydrophobic beads coated with PVLA. The attachment was independent of the amount of immobilized PVLA; rather, it was dependent on the hydrophobicity of the beads with PVLA. To simplify the surface of the hydrophobic beads with PVLA, galactopyranoses were covalently linked to chitosan beads via hydrophobic spacer arms, and hepatocyte attachment was compared among the prepared beads. The beads with spacer arms containing phenylalanine and a phthalic moiety showed increased hepatocyte attachment, which was elicited by galactose residues on the beads. These results suggest that rotational restriction or stiffness and hydrophobicity due to the phenyl moiety are essential to enhance the specificity of terminal galactose in PVLA. This analysis contributes to the design and optimization of an artificial ligand for cellular receptors recognizing surgar moieties. © 1995 John Wiley & Sons, Inc.
Catabolite repression in the gram‐positive bacteria: Generation of negative regulators of transcription
Authors: Stewart George C. 
Published: May 2005

AbstractOperons subject to catabolite repression (CR) in the gram‐positive bacteria appear to be transcriptionally regulated by negative acting catabolite repressors. Cis elements within the promoter regions of a few CR operons have been identified as the target sequences for these repressors. It has also been proposed that sequences internal to the transcriptional unit may represent targets for recognition of the operons as catabolite repressible. The precise mechanism(s) of regulation have yet to be worked out. © 1993 Wiley‐Liss, Inc.
Eukaryotic‐like protein serine/threonine kinases in Myxococcus xanthus, a developmental bacterium exhibiting social behavior
Authors: Munoz‐Dorado Jose , Inouye Sumiko , Inouye Masayori 
Published: May 2005

AbstractMyxococcus xanthus, a gram‐negative bacterium exhibits a spectacular life cycle and social behavior. Its developmental cycle and multicellular morphogenesis resemble those of eukaryotic slime molds such as Dictyostelium discoideum. On the basis of this resemblance, we explored the existence of eukaryotic‐like protein serine/threonine kinases which are known to play important roles in signal transduction during development of D. discoideum. It was indeed found that M. xanthus contains a large family of protein serine/threonine kinases related to the eukaryotic enzymes. This is the first unambiguous demonstration of eukaryotic‐like protein serine/threonine kinases in the prokaryotes. © 1993 Wiley‐Liss, Inc.
The phosphorelay signal transduction pathway in the initiation of Bacillus subtilis sporulation
Authors: Hoch James A. 
Published: May 2005

AbstractThe formation of spores in Bacillus subtilis is a developmental process under genetic control. The decision to either divide or sporulate is regulated by the state of phosphorylation of the Spo0A transcription factor. Phosphorylated Spo0A (Spo0A ∼ P) is both a repressor and an activator of transcription depending on the promoter it is affecting. Spo0A ∼ P is the end product of the phosphorelay, a signal transduction system linking environmental information to the activation of sporulation. Activation or deinhibition of two ATP‐dependent kinases, KinA and KinB, to phosphorylate the Spo0F secondary messenger initiates the phosphorelay. Spo0F ∼ P is the substrate for the Spo0B protein, a phosphoprotein phosphotransferase which transfers the phosphate group to Spo0A. The Spo0A ∼ P formed from this pathway orchestrates transcription events during the initial stage of spore development through direct effects on a variety of promoters and through the use of other transcription factors, termed transition state regulators, whose activity it controls. Because commitment to sporulation has serious cellular programming consequences and is not undertaken capriciously, the phosphorelay is subject to a variety of complex controls on the flow of phosphate through its components. © 1993 Wiley‐Liss, Inc.
Signal transduction in chemotaxis mediated by the bacterial phosphotransferase system
Authors: Titgemeyer Friedrich 
Published: May 2005

AbstractGram‐negative bacteria are able to respond chemotactically to carbohydrates which are substrates of the bacterial phosphoenolpyruvate:sugar phosphotransferase system (PTS). The mechanism of signal transduction in PTS‐mediated chemotaxis is different from the well‐studied mechanism involving methyl‐accepting chemotaxis proteins (MCPs). In PTS‐mediated chemotaxis, carbohydrate transport is required, and phosphorylation seems to be involved in both excitation and adaptation. In this review the roles of the components of the PTS in chemotactic signal transduction are discussed. © 1993 Wiley‐Liss, Inc.
Okadaic acid as an inducer of the 78‐kDa glucose‐regulated protein in 9L rat brain tumor cells
Authors: Hou Ming‐Chin , Shen Chi‐Hsiu , Lee Wen‐Chuan , Lai Yiu‐Kay 
Published: May 2005

AbstractOkadaic acid (OA), a potent inhibitor of protein phosphatases 1 and 2A, has been widely used as a tool for unravelling the regulation of cellular metabolic processes involving protein phosphorylation/dephosphorylation. It has recently been found that OA can induce reversible hyperphosphorylation of vimentin and reorganization of intermediate filaments [Lee et al., J. Cell. Biochem. 49: 378–393, 1992]. We report here that OA specifically induced the synthesis of a 78‐kDa protein, which was identified as the 78‐kDa glucose‐regulated protein (GRP78) by two‐dimensional sodium dodecylsulfate‐polyacrylamide gel electrophoresis and peptide mapping. The induction of GRP78 by OA was dose‐dependent and reversible. For 7 h treatments, GRP78 synthesis was initially enhanced under 50 nM OA and became the highest (about 6‐fold) under 200 nM OA. Meanwhile, under 200 nM OA, GRP78 synthesis was initially enhanced after 4 h and reached its maximal level (about 8‐fold) after 15 h of treatment. Subsequently, upon removal of OA, the level of OA‐induced GRP78 was reduced to basal level after 12 h of recovery. Induction of GRP78 synthesis by OA was abolished in cells pretreated with actinomycin D and cycloheximide, indicating that it was regulated at the transcriptional level and its induction required de novo protein synthesis. Furthermore, OA suppressed protein glycosylation, and the result lent support to the hypothesis that suppression of protein glycosylation may correlate with induction of GRP78 synthesis. © 1993 Wiley‐Liss, Inc.
Developing consumer/ survivor/recovering voice and its impact on services and research: Our experience with the SAMHSA Women, Co‐Occurring Disorders and Violence Study
Authors: Mockus Susan , Mars Laura Cinq , Ovard Dorothy Guazzo , Mazelis Ruta , Bjelajac Paula , Grady Janice , LaClair Christine , Livingston Cardenia , Slavin Sharon , Williams Susan , McKinney Jacki 
Published: May 2005

AbstractIntegrating consumer/survivor/recovering (C/S/R) women in the Substance Abuse and Mental Health Services Administration's Women, Co‐Occurring Disorders and Violence Study involved both struggles and growth. The C/S/R women and all of our professional allies, both individually and collectively, greatly enhanced the study by overcoming what earlier seemed to be insurmountable obstacles. Integral to the C/S/R group's personal and professional growth was the development and expression of their individual and collective voices. Documenting this history and the impact that the collaboration between the C/S/R women and other professional staff had on the study is of vital importance in the field of research and advocacy. © 2005 Wiley Periodicals, Inc. J Comm Psychol 33: 513–525, 2005.
High‐pressure liquid‐chromatographic determination of the anthelmintic drug mebendazole in plasma
Authors: Karlaganis G. , Münst G. J. , Bircher J. 
Published: May 2005

AbstractA procedure for determining the anthelmintic drug mebendazole in plasma of patients is described. Mebendazole together with the internal standard ciclobendazole is extracted with chloroform at pH 11. The extract is analyzed isocratically on a LiChrosorb SI 60 column with a mobile phase consisting of acetonitrile/water‐saturated chloroform/ammonia (75/92.5/0.1) at 307 nm. Reproducibility with a coefficient of variation of 3 to 10% is attainable for the concentration range of 20 to 200 ng mebendazole/ml plasma. Mebendazole plasma concentrations in patients with echinococcosis on chronic therapy with mebendazole ranged from 6 to 117 ng/ml.
Resolution of equine estrogens using glass capillary columns
Authors: Pillai G. K. , McErlane K. M. 
Published: May 2005

AbstractA rapid and specific procedure is described for the resolution of nine steroids present in conjugated estrogen preparations. Resolution is achieved on a short glass capillary column coated with Silar 10C after dual derivatization to oxime‐trimethylsilyl ethers.
Correlation between excess adsorption data measured for solvent mixture/adsorbent systems and RM values obtained for different solutes chromatographed in binary mobile phases
Authors: Ościk‐Mendyk B. , Róz̈ło J. K. , Jaroniec M. 
Published: May 2005

AbstractThis paper concerns the application of excess adsorption isotherms, measured for solvent mixture/adsorbent systems, to the characterization of TLC data. For this purpose the excess adsorption isotherms for three liquid mixtures: cyclohexane/ benzene, benzene/acetone, and carbon tetrachloride/ethyl acetate on silica gel at 20°C have been measured. These mixtures have been used as binary mobile phases in TLC measurements. It has been shown for a given solute in binary mobile phase that the quantity RM is a simple function of the excess adsorption. Parameters of this function have been used to characterize chromatographic systems with binary mobile phases.
Stimultaneous quantitative analysis using dual capillary columns of different polarities
Authors: Wright C. W. 
Published: May 2005

AbstractComplex organic mixtures, such as coal liquefaction and oil shale products and by‐products, are comprised of hundreds or thousands of individual components. State‐of‐the‐art high resolution gas chromatography does not always provide sufficient resolution to allow accurate quantitation or identification of many compounds of interest. The concept of dual capillary column chromatography combines the different resolving characteristics of two capillary columns coated with different stationary phases into a single chromatographic run. In this approach, both columns are connected to the same injection port. Analysis of complex mixtures in this fashion can confirm the identification and quantitation of components on two columns of different polarity with little increased analysis time, can provide a means of obtaining quantitative data for individual components which are known to coelute on any one column, and can alert one to unknown coelution problems that would be undetected by gas chromatographic analysis on a single capillary column.Simultaneous dual column analysis was applied to three samples, the neutral polycyclic aromatic hydrocarbon (PAH) fraction of a Solvent Refined Coal‐II (SRC‐II) heavy distillate, the nitrogen‐containing polycyclic aromatic compound (N‐PAC) fraction of an SRC‐II heavy distillate, and the basic fraction from a shale oil process water. Fused silica capillary columns coated with SE‐54 and Durawax 3 were used for the analyses of the heavy distillate, while SE‐54 an Carbowax 20M capillary columns were used for the analysis of the process water.
Isomer‐specific separation and quantitation of tetrachlorodibenzo‐p‐dioxins by HRGC and HRGC/MS
Authors: Onuska F. I. , Wilkinson R. J. , Terry K. 
Published: May 2005

AbstractA method is described for the determination of 22 tetrachlorodibenzo‐p‐dioxin isomers at the low part‐per‐trillion (ppt) level. High resolution, narrow bore, open tubular columns (OTCs) with 100 μm i.d. can achieve better separations than presently used 320 or 250 μm i.d. columns in about half the total time. Relative retention times and response factors for all 22 TCDD isomers are presented for the electron capture detection and for the molecular ion mass of individual isomers under electron impact ionization with selected ion monitoring (SIM).