bluuebunny/crossref_metadata_2025_split huggingface dataset:
Patterns of emotional availability among young mothers and their infants: A dydaic, contextual analysis
Authors: Easterbrooks M. Ann , Chaudhuri Jana H. , Gestsdottir Steinunn 
Published: July 2005

AbstractThe aim of this study was to examine patterns of emotional availability among 80 young mothers (under 21 years at their child's birth) and their infants, and to identify contextual and individual factors associated with different patterns of emotional availability. To operationalize the dyadic aspect of emotional availability, cluster analysis of the Emotional Availability Scales, third edition (EAS; Biringen, Robinson, & Emde, 1998) was conducted on mother and infant scales simultaneously. Four distinct groups of emotional availability patterns emerged, reflecting synchrony and asynchrony between maternal and child behavior: (a) low‐functioning dyads, (b) average dyads, (c) average parenting/disengaged infants, and (d) high‐functioning dyads. Further analyses revealed that mothers in different clusters differed on outcomes such as depressive symptomatology, social support, and relationships with their own mothers. The clusters and the variables related to them demonstrate the various challenges in integrating the dual tasks of adolescent and parenting development among young mothers. The clinical implications of these patterns of emotional availability and live context are discussed.
A study of biologically active peptide sequences (P‐15) on the surface of an ABM scaffold (PepGen P‐15™) using AFM and FTIR
Authors: Hole Bhushan B. , Schwarz James A. , Gilbert Jeremy L. , Atkinson Brent L. 
Published: July 2005

AbstractCellular response to any biomaterial surface is governed by a number of factors including topography, surface chemistry, surface charge, structural heterogeneity, and physiological conditions. Understanding these factors at the nanoscale level is crucial to develop improved biomaterials. Any changes in these properties due to surface modifications need to be addressed properly, as they could have significant impact on the cellular interaction with biomaterials. In this study, the topography and surface chemistry of commercially available tissue engineered xenograft, PepGen P‐15™ [comprised of a synthetic peptide P‐15 irreversibly attached to anorganic bovine bone mineral (OsteoGraf/‐N®)] was studied using Atomic Force Microscopy (AFM), and Fourier Transform Infrared Spectroscopy (FTIR). FTIR confirmed the presence of the peptide on the surface of PepGen P‐15™. Changes in the peptide conformation, which includes a decrease in the β‐strand accompanied by an increase in unordered structures/random coil structures after attachment on OsteoGraf/‐N® is observed. Specific functional groups, which are involved in the binding mechanism, are identified. The results suggest that the attachment of the peptide on OsteoGraf/‐N® occurs via a specific surface docking ionic interaction involving the C‐terminal carboxylic group on the peptide with positive domains generated by hydroxyl vacancies on the apatite surface. © 2005 Wiley Periodicals, Inc. J Biomed Mater Res, 2005
Design of functionally graded dental implant in the presence of cancellous bone
Authors: Hedia H. S. 
Published: July 2005

AbstractIn a previous work by the author [Hedia HS, Mahmoud NA. Biomed Mater Eng 2004;14(2):133–143], a functionally graded material (FGM) dental implant was designed without cancellous bone in the model. In this investigation, the effect of the presence of cancellous bone as a thin layer around the dental implant was investigated. It is well known that the main inorganic component of natural bone is hydroxyapatite (HAP) and that the main organic component is collagen (Col). HAP implants are not bioabsorbable, and because induction of bone into and around the artificially made HAP is not always satisfactory, loosening or breakage of HAP implants might occur after implantation in the clinical application. The development of a new material that is bioabsorbable and that has osteoconductive activity is needed. Therefore, the aim of the current investigation was to design an implant, in the presence of cancellous bone as a thin layer around it, from FGM. In this study, a novel biomaterial, Col/HAP, as a FGM, was developed using the finite element and optimization techniques that are available in the ANSYS package. These materials have a self‐organized character similar to that of natural bone. The investigations have shown that the maximum stress in the cortical bone and cancellous bone for the Col/HAP functionally graded implant has been reduced by about 40% and 19%, respectively, compared with currently used titanium dental implants. © 2005 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2005
Using pH‐sensitive hydrogels containing cubane as a crosslinking agent for oral delivery of insulin
Authors: Mahkam Mehrdad 
Published: July 2005

AbstractThe goal of oral insulin delivery devices is to protect the sensitive drug from proteolytic degradation in the stomach and upper portion of the small intestine. Copolymers of 2‐hydroxyethyl methacrylate (HEMA) and methacrylic acid (MAA) based hydrogels containing 2, 4, and 6% of a crosslinking agent (CA) were studied as drug delivery systems. Cubane‐1, 4‐dicarboxylic acid (CDA) was linked to two HEMA groups as CA. Radical copolymerizations of HEMA and MAA with the various ratios of CA were performed at 70°C. The compositions of the crosslinked three‐dimensional polymers were determined using Fourier transform infrared spectroscopy. Glass‐transition temperature of the network polymers was determined calorimetrically. The effect of copolymer composition on the swelling behavior and hydrolytic degradation was studied in simulated gastric fluid (pH 1) and simulated intestinal fluid (pH 7.4). The swelling and hydrolytic behavior of the copolymers was dependent on the content of MAA groups and caused a decrease in gel swelling in simulated gastric fluid or an increase in gel swelling in simulated intestinal fluid. The drug‐release profiles indicate that the amount of drug release depends on their degree of swelling and crosslinking. © 2005 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2005
Bone compaction enhances fixation of hydroxyapatite‐coated implants in a canine gap model
Authors: Kold Søren , Rahbek Ole , Zippor Berit , Bechtold Joan E. , Søballe Kjeld 
Published: July 2005

AbstractPrimary cementless joint replacement depends partly on the ability of bone to heal into those areas of an inserted implant where a gap to surrounding bone initially exists. A new bone preparation technique, compaction, has enhanced gap‐healing around grit‐blasted implants without osteoconductive properties. However, hydroxyapatite (HA) porous‐coated implants with osteoconductive properties are often inserted clinically to enhance gap healing and implant fixation. It is unknown whether the osteoconductive properties of HA porous‐coated implants might overwhelm the beneficial effects of compaction on gap healing. Therefore, we compared the compaction technique with the conventional bone‐removing technique, drilling, using HA porous‐coated implants in a canine gap model. HA porous‐coated titanium implants were bilaterally inserted into oversized cavities of the proximal humeri of seven dogs. Each dog served as its own control. Thus, one humerus had the implant cavity prepared with compaction, the other with drilling. Two weeks after surgery push‐out test and histomorphometry was performed. Compaction significantly increased ultimate shear strength, energy absorption, apparent shear stiffness, bone implant contact, and peri‐implant bone density. The results of this study suggest that compaction may enhance gap healing when osteoconductive HA porous coated implants are inserted in joint replacements. © 2005 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2005
Effect of niobium content on the microstructure and thermal properties of fluorapatite glass‐ceramics
Authors: Denry I. L. , Holloway J. A. , Nakkula R. J. , Walters J. D. 
Published: July 2005

AbstractNiobium oxide has been shown to improve biocompatibility and promote bioactivity. The purpose of this study was to evaluate the effect of niobium oxide additions on the microstructure and thermal properties of fluorapatite glass‐ceramics for biomedical applications. Four glass‐ceramic compositions with increasing amounts of niobium oxide from 0 to 5 wt % were prepared. The glass compositions were melted at 1525°C for 3 h, quenched, ground, melted again at 1525°C for 3 h and furnace cooled. The coefficient of thermal expansion was measured by dilatometry. The crystallization behavior was evaluated by differential thermal analysis. The nature of the crystalline phases was investigated by X‐ray diffraction. The microstructure was studied by SEM. In addition, the cytotoxicity of the ceramics was evaluated according to the ASTM standard F895‐84. The results from X‐ray diffraction analyses showed that fluorapatite was the major crystalline phase in all glass‐ceramics. Differential thermal analyses revealed that fluorapatite crystallization occurred between 800 and 934°C depending on the composition. The coefficient of thermal expansion varied from 7.6 to 9.4 × 10−6/°C. The microstructure after heat treatment at 975°C for 30 min consisted of submicroscopic fluorapatite crystals (200–300 nm) for all niobium‐containing glass‐ceramics, whereas the niobium‐free glass‐ceramic contained needle‐shaped fluorapatite crystals, 2 μm in length. None of the glass‐ceramics tested exhibited any cytotoxic activity as tested by ASTM standard F895‐84. © 2005 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2005
Skin regeneration using keratinocytes and dermal fibroblasts cultured on biodegradable microspherical polymer scaffolds
Authors: Kim Sang‐Soo , Gwak So‐Jung , Choi Cha Yong , Kim Byung‐Soo 
Published: July 2005

AbstractBioartificial skin sheet grafts have been utilized to treat large burns and chronic ulcers. However, the trypsinization step to harvest cultured skin grafts from culture dishes damages the cells by breaking the anchoring proteins and lowers their uptake ratio after transplantation. In addition, epidermal sheet grafts require a long fabrication period. To overcome these limitations, we utilized biodegradable poly(lactide‐co‐glycolide) (PLGA) microspheres as both cell culture matrix and transplantation vehicle of skin cells for skin regeneration in this study. This method could avoid the trypsinization step and have a relatively short preparation period. Human keratinocytes and dermal fibroblasts cultured on PLGA microspheres in spinner flasks proliferated by 3.0‐fold and 9.4‐fold, respectively, after 10 days. When both types of cells cultured on PLGA microspheres were reinoculated onto culture dishes, the cells migrated from the PLGA microspheres to the culture dish surface, grew, and formed a confluent cell layer within 5 days, showing the growth and migration abilities of the cells cultured on PLGA microspheres. Full‐thickness skin wounds created on the back of athymic mice were either treated with transplantation of keratinocytes and dermal fibroblasts cultured on microspheres (cell‐transplanted group), treated with PLGA microspheres alone (microsphere‐implanted group), or covered with dressing materials without treatment (untreated group). Three weeks after the treatments, differentiated epithelium that stained positively for cytokeratin, a marker of epidermis, was observed in the cell‐transplanted group, while the microsphere‐implanted group and untreated group showed incomplete reepithelialization. Dermal regeneration with positive staining for vimentin, a marker of dermal fibroblast, was observed in the cell‐transplanted group. Regenerated dermis with positive staining for vimentin was partly observed in the microsphere‐implanted group and untreated group. These results suggest that transplantation of keratinocytes and dermal fibroblasts cultured on PLGA microspheres could be potentially useful as an alternative to bioartificial skin grafts for the treatment of skin wounds. © 2005 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2005
Free volume study on calcification process in an intraocular lens after cataract surgery
Authors: Ramani R. , Parihar J.K.S. , Ranganathaiah C. , Awasthi P. , Alam S. , Mathur G.N. 
Published: July 2005

AbstractAn opacified intraocular lens explanted from a patient in the postoperative period after phacoemulsification was investigated to find the cause of opacification. From the UV‐visible and energy dispersive X‐ray spectroscopy (EDS) measurements, the opacification in the present case seems to be due to calcification of the intraocular lens and not due to modification in the UV absorber material of the lens. The average free volume size of the intraocular lens both in unimplanted and explanted state were obtained from positron lifetime spectroscopy (PLS). Further, the combined FTIR and PLS results indicate that calcium gets into the free volume cavities of the intraocular lens matrix as a cationic moiety, may be in the form of Ca++. The small decrease in glass transition temperature of the calcified lens seems to indicate the plasticizing action of calcium ions. The present results could be of some use in the design of the intraocular lens material in which calcification would be minimum. © 2005 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2005
A class of 2D graphical representations of RNA secondary structures and the analysis of similarity based on them
Authors: Yao Yu‐Hua , Nan Xu‐Ying , Wang Tian‐Ming 
Published: July 2005

AbstractBased on the concepts of cell and system of graphical representation, a class of 2D graphical representations of RNA secondary structures are given in terms of classifications of bases of nucleic acids. The representations can completely avoid loss of information associated with crossing and overlapping of the corresponding curve. As an application, we make quantitative comparisons for a set of RNA secondary structures at the 3′‐terminus of different viruses based on the graphical representations. The examination of similarities/dissimilarities illustrates the utility of the approach. © 2005 Wiley Periodicals, Inc. J Comput Chem 26: 1339–1346, 2005
Are AM1 ligand‐protein binding enthalpies good enough for use in the rational design of new drugs?
Authors: Villar R. , Gil M. J. , García J. I. , Martínez‐Merino V. 
Published: July 2005

AbstractWe have examined the performance of semiempirical quantum mechanical methods in solving the problem of accurately predicting protein‐ligand binding energies and geometries. Firstly, AM1 and PM3 geometries and binding enthalpies between small molecules that simulate typical ligand‐protein interactions were compared with high level quantum mechanical techniques that include electronic correlation (e.g., MP2 or B3LYP). Species studied include alkanes, aromatic systems, molecules including groups with hypervalent sulfur or with donor or acceptor hydrogen bonding capability, as well as ammonium or carboxylate ions. B3LYP/6‐311+G(2d,p) binding energies correlated very well with the BSSE corrected MP2/6‐31G(d) values. AM1 binding enthalpies also showed good correlation with MP2 values, and their systematic deviation is acceptable when enthalpies are used for the comparison of interaction energies between ligands and a target. PM3 otherwise gave erratic energy differences in comparison to the B3LYP or MP2 approaches. As one would expect, the geometries of the binding complexes showed the known limitations of the semiempirical and DFT methods. AM1 calculations were subsequently applied to a test set consisting of “real” protein active site‐ligand complexes. Preliminary results indicate that AM1 could be a valuable tool for the design of new drugs using proteins as templates. This approach also has a reasonable computational cost. The ligand‐protein X‐ray structures were reasonably reproduced by AM1 calculations and the corresponding AM1 binding enthalpies are in agreement with the results from the “small molecules” test set. © 2005 Wiley Periodicals, Inc. J Comput Chem 26: 1347–1358, 2005
Using protein/creatinine ratios in random urine
Authors: Watanabe Mitsuhiro , Funabiki Kazuhiko , Tsuge Toshinao , Maeda Kunimi , Horikoshi Satoshi , Tomino Yasuhiko 
Published: July 2005

AbstractWe assessed the new test paper Multistix PRO IOLS, in which the ±region of the conventional test for protein was altered so that creatinine correction became possible. Urinary samples from 235 patients with various renal diseases were obtained from the Juntendo University Hospital. We examined 1) the correlation between qualitatively measured values of urinary protein by the new test paper and the conventional test paper, and 2) the correlation between qualitative and quantitative values of protein (P), creatinine (C), and the P/C ratio measured by the new test paper. There was a good correlation between the P/C ratio observed with the new test paper and that observed by quantitative analysis. There was also a good correlation of the P/C ratio between 24‐hr urine and urinary samples obtained at any time of day. Thus, it appears that the results obtained from urinary samples any time of day can predict the amount of protein excreted during the day. J. Clin. Lab. Anal. 19:160–166, 2005. © 2005 Wiley‐Liss, Inc.
The non‐proteolytically active thrombin peptide TP508 stimulates angiogenic sprouting
Authors: Vartanian Keri B. , Chen Helen Y.S. , Kennedy Janelle , Beck Shaleen K. , Ryaby James T. , Wang Hali , Hoying James B. 
Published: July 2005

AbstractThrombin is a serine protease that promotes platelet aggregation, blood coagulation, and tissue repair. A peptide derived from a non‐proteolytically active region of thrombin, TP508, also promotes tissue repair and increased vascularity, yet does not activate platelet and inflammatory cascades. TP508 binds to cells with high affinity and stimulates cells independent of the proteolytically active thrombin receptors (PARs) and thus is considered to activate a non‐proteolytically active receptor (non‐PAR) pathway. Using a model of angiogenic sprouting, we further defined the angiogenic potential of TP508 and investigated the role of non‐proteolytic, thrombin‐mediated pathways in angiogenesis. The assay involves measuring angiogenic sprouting from cultured, intact microvessel fragments. In this assay, TP508 stimulated angiogenic sprouting to an extent similar to or greater than the potent angiogenic factor, VEGF. However, TP508 had no significant effect on the number of sprouts that formed per vessel. In contrast to TP508, proteolytically active receptor agonists had no effect or inhibited angiogenic sprouting. The increased sprouting activity stimulated by TP508 was VEGF dependent but did not involve an increase in VEGF mRNA expression above baseline levels. These results suggest that TP508 acts early in angiogenesis and directly on microvascular cells to accelerate sprouting, but not to induce more sprouting, in a manner different than the intact thrombin molecule. © 2005 Wiley‐Liss, Inc.
CCL18‐stimulated upregulation of collagen production in lung fibroblasts requires Sp1 signaling and basal Smad3 activity
Authors: Luzina Irina G. , Tsymbalyuk Natalya , Choi Jung , Hasday Jeffrey D. , Atamas Sergei P. 
Published: July 2005

AbstractA CC chemokine CCL18 stimulates collagen production in pulmonary fibroblasts through an unknown signaling mechanism. In this study, involvement of Sp1 and Smad3 in CCL18 signaling in primary human pulmonary fibroblast cultures was investigated. Phosphorylation of Sp1, DNA‐binding by Sp1, and the activity of an Sp1‐dependent reporter were all increased in response to CCL18 stimulation. CCL18 did not stimulate a detectable increase in Smad3 phosphorylation or Smad3/4 DNA‐binding activity, although some basal phosphorylation and DNA binding by Smad3/4 were noted. Transient overexpression of dominant negative mutants of Sp1 and Smad3 abrogated CCL18‐dependent upregulation as well as basal production of collagen. These observations suggested that CCL18 activates collagen production in pulmonary fibroblasts through an Sp1‐dependent pathway that also requires basal Smad3 activity. Possible involvement of autocrine TGF‐β in CCL18 signaling was considered. CCL18 stimulated increases in collagen mRNA and protein production without detectable changes in TGF‐β1, ‐β2, and ‐β3 mRNA or protein levels. Neutralizing anti‐TGF‐β antibodies, latency‐associated peptide, ALK5‐specific inhibitor SD431542, and an inhibitor of the protease‐dependent TGF‐β activation aprotinin, each failed to block CCL18‐stimulated collagen production. These observations suggest that both CCL18 signaling in pulmonary fibroblasts and basal Smad3 activity are independent of autocrine TGF‐β. © 2005 Wiley‐Liss, Inc.
Trypsin and thrombin accelerate aggregation of human endocrine pancreas precursor cells
Authors: Wei Chiju , Geras‐Raaka Elizabeth , Marcus‐Samuels Bernice , Oron Yoram , Gershengorn Marvin C. 
Published: July 2005

AbstractHuman islet‐derived precursor cells (hIPCs) and human pancreatic ductal carcinoma (PANC‐1) cells can be induced to form aggregates that subsequently differentiate into hormone‐expressing islet‐like cell aggregates (ICAs). We show that challenge of hIPCs or PANC‐1 cells with thrombin or trypsin resulted in stimulation of signaling via the inositol‐tris‐phosphate second messenger pathway leading to rapid, transient increases in cytosolic calcium ion concentration in the majority of the cells. Because we found that hIPCs, PANC‐1 cells, human fetal pancreas, and human adult islets express two protease‐activated receptors (PARs), PAR‐1 and PAR‐2, we tested whether the effects of thrombin and trypsin were mediated, at least in part, by these receptors. Peptide agonists that are relatively specific for PAR‐1 (SFLLRN‐amide) or PAR‐2 (SLIGRL‐amide) stimulated increases in inositol phosphates and cytosolic calcium ion concentration, and increased the phosphorylation of Rho, a small G‐protein associated with cytoskeletal changes affecting cellular morphology and migration. Most importantly, we show that these agonists increased the rate of hIPC aggregation leading to the formation of more viable, smaller ICAs. Our data show that thrombin and trypsin accelerate aggregation, an early stage of hIPC differentiation in vitro, and imply that pancreatic trypsin and thrombin may be involved in islet development in vivo. J. Cell. Physiol. 206: 322–328, 2006. Published 2005 Wiley‐Liss, Inc.
3,5,3′‐triiodothyronine (T3) is a survival factor for pancreatic β‐cells undergoing apoptosis
Authors: Verga Falzacappa Cecilia , Panacchia Laura , Bucci Barbara , Stigliano Antonio , Cavallo Maria Gisella , Brunetti Ercole , Toscano Vincenzo , Misiti Silvia 
Published: July 2005

Abstract3,5,3′‐triiodothyronine (T3) is essential for the growth and the regulation of metabolic functions, moreover, the growth‐stimulatory effect of T3 has largely been demonstrated and the pathways via which T3 promotes cell growth have been recently investigated. Type 1 diabetes (T1D) is due to the destruction of β‐cells, which occurs even through apoptosis. Aim of our study was to analyze whether T3 could have an antiapoptotic effect on cultured β‐cells undergoing apoptosis. We have demonstrated that T3 promotes cell proliferation in islet β‐cell lines (rRINm5F and hCM) provoking an increment in cell number (up to 55%: rRINm5F and 45%: hCM), cell viability, and BrdU incorporation, and regulating the cell cycle‐related molecules (cyc A, D1, E, and p27kip1). T3 inhibited the apoptotic process induced by streptozocin, S‐Nitroso‐N‐Acetylpenicylamine (SNAP), and H2O2 via regulation of the pro‐ and anti‐apoptotic factors Bcl‐2, Bcl‐XL, Bad, Bax, and Caspase 3. The T3 protective effect was PI‐3 K‐, but not MAPK‐ or PKA‐mediated, involving pAktThr308. Thus, T3 could be considered a survival factor protecting islet β‐cells from apoptosis. J. Cell. Physiol. 206: 309–321, 2006. © 2005 Wiley‐Liss, Inc.