bluuebunny/crossref_metadata_2025_split huggingface dataset:
Behavioral and neuroanatomical characterization of the Fmr1 knockout mouse
Authors: Mineur Yann S. , Sluyter Frans , de Wit Sanne , Oostra Ben A. , Crusio Wim E. 
Published: October 2004

AbstractPrevious studies showed the Fmr1 knockout (KO) mouse to be an excellent animal model for human fragile‐X syndrome. The aim of this study was to further characterize the phenotype of these animals. Neuroanatomically, KO male mice were compared to wild‐types (littermates) with respect to their sizes of hippocampal intra‐ and infrapyramidal mossy fiber (IIPMF) terminal fields. Behaviorally, they were tested in four different paradigms, each measuring different aspects of cognitive and emotional behavior: elevated plus maze (anxiety), neutral cage (aggression), open field (exploration), and radial maze (spatial memory). The results showed a diminished ability for radial maze learning associated with smaller sizes of IIPMF terminal fields. In addition, Fmr1 knockout animals exhibited increased locomotor activity, while no differences were found for aggression and anxiety. These data suggest the involvement of FMRP protein in the development of spatial learning and the sprouting of IIPMF terminal fields. Hippocampus 2002;12:39–46. © 2002 Wiley‐Liss, Inc.
Genetic approach to variability of memory systems: Analysis of place vs. response learning and Fos‐related expression in hippocampal and striatal areas of C57BL/6 and DBA/2 mice
Authors: Passino Enrica , Middei Silvia , Restivo Leonardo , Bertaina‐Anglade Valérie , Ammassari‐Teule Martine 
Published: October 2004

AbstractC57 and DBA mice were trained in a crossed maze to assess possible strain differences in place or response learning as a function of training duration ( 8 or 17 days) and extramaze cueing conditions. The first condition consisted of a diffuse visually cued environment (rich cueing). The second was the same plus an explicit visual cue marking the direction of the baited arm (rich cueing plus cue). The third was a featureless environment (poor cueing). During training, mice were released from the south arm and rewarded in the east arm. Probe trials on which mice were released from the north arm and allowed to choose either the east (place learning) or the west (response learning) arm were given either on the ninth (PT1) or the eighteenth (PT2) days. Strain × context differences in the activation of the dorsal hippocampus and the dorsolateral striatum were examined by analyzing Fos expression following each probe trial. Results first showed that C57 were essentially place‐learners, whereas no learning modality was predominant in DBA, except on the PT2 run with the explicit cue available. Examination of Fos expression in C57 trained under “rich cueing” and “rich cueing plus cue” conditions revealed a strong and parallel increase of immunoreactivity in the hippocampus and dorsolateral striatum following PT1 that decreased under PT2. In that strain, the similar time‐course variation of Fos expression in both areas suggests a simultaneous involvement of hippocampal‐ and striatal‐based learning mechanisms, even if those controlled by the hippocampus were prevailing on those controlled by the dorsolateral striatum. In DBA mice, however, the absence of any preferential learning modality was associated with 1) a consistent hippocampal activation persistent across probe trials, and 2) a global superior activation of the dorsolateral striatum. Distinct patterns of Fos expression were therefore associated with every strain‐specific learning modality. In each strain, however, each modality was found to be remarkably stable, whatever the training duration and the cueing conditions. Hippocampus 2002;12:63–75. © 2002 Wiley‐Liss, Inc.
Early Head Start: A dynamic new program for infants and toddlers and their families
Authors: Raikes Helen H. , Love John M. 
Published: October 2004

AbstractIn just 6 years, Early Head Start has grown from 68 initial grantees to some 650 programs and, by early 2001, was serving more than 55,000 families with infants and toddlers throughout the country. With an increasing share of the federal Head Start budget, Early Head Start is an ambitious effort in which the Administration on Children, Youth and Families (ACYF) is responding to the “quiet crisis” facing infants and toddlers in this country, as identified by the Carnegie Corporation of New York in its 1994 Starting Points. This overview to the special issue of the journal describes the program, its growth, and the changing policy and program environment of its first 5 years; explains how the federal and regional infrastructure supports Early Head Start through training, technical assistance, and monitoring; summarizes the design and conduct of the national evaluation and local research studies; presents the key lessons that the research has yielded so far; and concludes with an assessment of the challenges that lie ahead for creating a solid base of knowledge for programs serving low‐income families with infants and toddlers. ©2002 Michigan Association for Infant Mental Health.
Improving child care quality in Early Head Start programs: A partnership model
Authors: Ontai Lenna L. , Hinrichs Sue , Beard Marti , Wilcox Brian L. 
Published: October 2004

AbstractMany Early Head Start (EHS) programs do not provide child care directly but instead contract with existing community child care agencies to provide services. Such arrangements challenge EHS programs to create unique ways to ensure quality in the child care component of the program. The current research project reports on the efforts of a partnership between an EHS program and community child care agency to improve child care quality. The goal was to systematically identify changes in quality made within the EHS program as the result of a system of monitoring and assessment carried out under the partnership. The current study utilized ITERS and Arnett scales to assess the quality of the community center‐based infant child care at the beginning of the EHS program and nine months later. The results indicate a significant improvement in some areas of child care whereas other areas appeared to be more difficult to enhance with the current method. Additionally, differential areas of improvement were found between infant and toddler classrooms. The discussion focuses on aspects of the partnership that most likely contributed to quality improvements. ©2002 Michigan Association for Infant Mental Health.
Development of the shields for tendon injury repair using polyvinyl alcohol — hydrogel ( PVA‐H)
Authors: Kobayashi Masanori , Toguchida Junya , Oka Masanori 
Published: October 2004

AbstractIn recent years, marked advances have been made in repair techniques for tendon injury, but the treatment of finger flexor tendon injury is still one of the most difficult and important problems in the orthopedic field. The main problem in tendon repair is adhesion between the tendon and surrounding tissue. To prevent this adhesion and achieve tendon union, we developed adhesion preventive shields for tendon repair using polyvinyl alcohol hydrogel ( PVA‐H) with 90% water content, and carried out an implant experiment using the deep flexor tendon of the third toe of domestic fowl. Injured tendons shielded with PVA‐H showed union at about 3 weeks after the operation without adhesion to the surrounding tissue and good function such as gliding and range of motion. Neither breakage of the PVA‐H shield itself nor infection, nor degeneration in the surrounding tissue were observed. These results confirmed that the tendon itself has repair ability, and the tendon is regenerated by synovial nutrition through PVA‐H. High water content PVA‐H may have clinically potential and be applicable to adhesion‐preventive shields for tendon repair. However, re‐rupture was observed, probably due to accidental tendon injury at an early period after the operation. In some cases, tendon immobilization methods to prevent re‐rupture might be necessary. © 2001 John Wiley & Sons, Inc. J Biomed Mater Res (Appl Biomater) 58: 344–351, 2001
Blends of stearyl poly(ethylene oxide) coupling‐polymer in chitosan as coating materials for polyurethane intravascular catheters
Authors: Wang Dong‐An , Ji Jian , Sun Yong‐Hong , Yu Guan‐Hua , Feng Lin‐Xian 
Published: October 2004

AbstractTo optimize the surface biocompatibility of the intravascular catheter, an amphiphilic coupling‐polymer of stearyl poly (ethylene oxide) —co— 4,4'‐methylene diphenyl diisocyanate—co— stearyl poly (ethylene oxide), for short MSPEO, was specially designed as the surface modifying additive (SMA). The blend of MSPEO in chitosan was coated on the outer wall of the catheters by the dip‐coating method. The surface analysis was carried out by ATR‐FTIR and contact angle measurements. The surface enrichment of MSPEO was confirmed. On the water interface, the larger the molecular weight of PEO was, the higher the surface enrichment. While on air interface, the case was the contrary. Three kinds of static test of clotting time, plasma recalcification time (PRT), prothrombin time (PT), and thrombin time (TT), as well as the static platelet adhesion experiment were carried out. The results indicated that the coated surface could resist the clotting effectively. In order to test the blood‐compatibility of the coated catheters under a shear of blood flow, the dynamic experiment was performed through a closed‐loop tubular system with the shear rate of 1500 s−1. The results of blood regular testing at six different times (0, 5,10, 20, 30, and 60 min) indicated that the biocompatibility of the coating was nearly ideal. Finally, the SMA‐MSPEO was proved to be non‐chronic‐toxic by animal experiments with rats and suitable as a coating material for clinical use. © 2001 John Wiley & Sons, Inc. J Biomed Mater Res (Appl Biomater) 58: 372–383, 2001
Inhibition of leukotriene function can modulate particulate‐induced changes in bone cell differentiation and activity
Authors: Anderson Gail I. , MacQuarrie Robyn , Osinga Chris , Chen Ying Fang , Langman Maxine , Gilbert Robert 
Published: October 2004

AbstractAseptic loosening remains the major problem facing arthroplasty longevity with particulates from component materials touted as the cause of periprosthetic osteolysis. Proposed mechanisms in aseptic bone loss include: increased resorption, increased differentiation of osteoclasts (and/or macrophages locally), and decreased osteoblastic bone formation. Leukotrienes participate in osteoclastic bone resorption. We investigated inhibiting leukotrienes synthesis, using ICI 230487, to ameliorate the effects of particulates on osteoclast pit formation and also assessed the effects of alendronate, a bisphosphonate, on pit formation. Three particulates were used: ultra high molecular weight polyethylene (UHMWPE), polymethylmethacrylate (PMMA) and hydroxyapatite (HA). Osteoclast resorption was increased with UHMWPE, PMMA, and HA particles. Interventions with alendronate and ICI 230487 reduced particulate‐induced osteoclast resorption. Both ICI 230487 and alendronate reduced osteoclast numbers at higher doses. To assess the effect of particulates on osteoclast and macrophage differentiation, mouse bone marrow was cultured and stained for tartrate resistant acid phosphatase colonies (TRAP+, osteoclasts) and nonspecific esterase positive colonies (NSE+, macrophage precursors). Particulates increased both TRAP+ and NSE+ colony formation. These increases were inhibited by ICI 230487. Particulates also inhibited osteoblast function assessed by the development of mineralized nodules and alkaline phosphatase positive (AP+) colony area. ICI 230487 partly protected osteoblast function from this particulate effect. Blockade of leukotriene production may prove a useful therapeutic intervention for particulate‐induced aseptic loosening by inhibiting resorptive activity, reducing the pro‐inflammatory cell populations induced and recruited by these particulates, as well as ameliorating the negative effects of inflammatory mediators on osteoblast function.© 2001 John Wiley & Sons, Inc. J Biomed Mater Res (Appl Biomater) 58: 406–414, 2001
Effects of filler composition and surface treatment on the characteristics of opaque resin composites
Authors: Yoshida Keiichi , Tanagawa Mika , Atsuta Mitsuru 
Published: October 2004

AbstractThe effects of filler composition and surface treatment of titanium dioxide (TiO2) on the shear bond strength to noble metal and mechanical properties of opaque dental resin composites were assessed. A series of fillers for resin composites were prepared with untreated TiO2 or treated silica/alumina‐coated TiO2 with silane coupling agent; these fillers were replaced with silanized SiO2 in increasing amounts. Each of various powder compositions were mixed with the liquid and applied to the surface of a silver‐palladium‐copper‐gold (Ag‐Pd‐Cu‐Au) alloy and light cured. A light‐activated resin‐veneering composite material was placed on top with the use of a brass ring mold and light cured. Specimens were stored at 37 °C in water for a period of 24 h. Additionally some specimens were thermocycled at 4 °C and 60 °C in water baths for 1 min each for 5000 cycles before shear mode testing was performed. Light‐activated opaque resin composites containing filler with specific filler compositions of 50 wt% of untreated TiO2—50 wt% of silanized SiO2 (untreated TiO250) and 40 wt% of untreated TiO2—60 wt% of silanized SiO2 (untreated TiO240) showed higher shear bond strengths to the Ag‐Pd‐Cu‐Au alloy than any other specific compositions when no thermocycling was involved. Surface treatment of TiO2 filler and TiO250‐ and TiO240‐opaque resin composites prepared thereof showed significantly higher shear bond strengths than untreated TiO250‐ and TiO240‐opaque resin composites when subjected to thermocycling. Surface‐treated opaque resin composite had significantly higher compressive and flexural strength than untreated opaque resin composite after immersion in water for 1 month. Scanning electron microscopy of the fractured opaque resin composite surface showed an interface failure between TiO2 and the matrix resin for untreated composite, and cohesive failure within the resin for surface‐treated composite. Surface‐treated TiO250 and TiO240 may be clinically useful as the filler for light‐activated opaque dental resin composites. © 2001 John Wiley & Sons, Inc. J Biomed Mater Res (Appl Biomater) 58: 525–530, 2001
Relating nickel‐induced tissue inflammation to nickel release in vivo
Authors: Wataha John C. , O'Dell Norris L. , Singh Baldev B. , Ghazi Mohamed , Whitford Gary M. , Lockwood Petra E. 
Published: October 2004

AbstractNickel has a number of adverse biological effects that have made the use of nickel in biomedical implants controversial. Yet information about the distribution of nickel in tissues around nickel‐containing implants is scarce. The purpose of the current study was to use a laser ablation technique, combined with inductively coupled mass spectroscopy, to assess the spatial distribution of nickel around nickel‐containing implants in vivo. Polyethylene, pure nickel wire, or a nickel‐containing alloy (Ni‐Cr) were implanted subcutaneously into rats for 7 days. The tissues were analyzed for Ni content and inflammation at 1‐mm intervals up to 5 mm away from the implants. The sham surgery sites and the polyethylene caused mild to moderate inflammation 1–2 mm from the implant site with no detectable nickel in the tissue. The nickel wire caused severe inflammation up to 5 mm away from the implant site with necrosis for 1 mm around the implant. Nickel concentrations reached 48 μg/g near the implants, falling exponentially to undetectable levels at 3–4 mm from the implants. The Ni‐Cr wire caused inflammation equivalent to polyethylene, with less than 4 μg/g of nickel present in the tissue for 1–2 mm around the implants. The current study showed that the laser‐ablation technique was well suited for the analysis of soft tissues for metal‐ion content, and that the nickel distribution in tissues correlated well with overt tissue inflammation. © 2001 John Wiley & Sons, Inc. J Biomed Mater Res (Appl Biomater) 58: 537–544, 2001
Biofilm formation and design features of indwelling silicone rubber tracheoesophageal voice prostheses—an electron microscopical study
Authors: Leunisse Casper , van Weissenbruch Ranny , Busscher Henk J. , van der Mei Henny C. , Dijk Freark , Albers Frans W. J. 
Published: October 2004

AbstractAfter total laryngectomy, voice can be restored with a silicone rubber tracheoesophageal voice prosthesis. However, biofilm formation and subsequent deterioration of the silicone material of the prosthesis will limit device life by impairing valve function. To simulate the natural process of biofilm development under dynamic nutrient conditions, a modified Robbins device was used to evaluate the biofilm‐related valve dysfunction of the Groningen, Provox2, Blom‐Singer indwelling, and VoiceMaster voice prostheses. Obstruction of the semicircular slit‐valved Groningen prosthesis leading to increased airway resistance was caused not only by a buildup of deposits on the esophageal flange and valve hat, but also by accumulation of deposits on the semicircular valve seating. The hinged flap valved Provox2 and indwelling Blom‐Singer prostheses failed to close sufficiently because of biofilm formation on the valve seating. The esophageal flange of the VoiceMaster prosthesis was affected, but the tripod structure of the ball valve was fully colonized up to the titanium sleeve, which interfered with proper valve opening and closure. These findings on biofilm formation could be used for the further development and modification of critical design features of voice prostheses to facilitate tracheoesophageal speech. © 2001 John Wiley & Sons, Inc. J Biomed Mater Res (Appl Biomater) 58: 556–563, 2001
Comparative analysis of the structure and thermal stability of sea urchin peristome and rat tail tendon collagen
Authors: Mayne Janice , Robinson John J. 
Published: October 2004

AbstractWe have purified collagen from two distinct sources; the vertebrate, rat tail tendon and an invertebrate, sea urchin adult tissue, the peristome. The collagenous nature of the purification products was confirmed by amino acid compositional analysis. Both preparations had high contents of glycine and proline residues and hydroxyproline was also present. The total pyrrolidine (proline + hydroxyproline) content decreased from 17.9 mole % in rat tail collagen to 12.9 mole % in peristome collagen. Distinctly different circular dichroic spectra were measured for these collagens. Analyses of spectra, measured as a function of temperature, revealed distinct thermal denaturation profiles. The melting temperature for rat tail collagen was 38.5°C, while the corresponding value for peristome collagen was significantly lower at 27°C. A similar thermal denaturation profile was obtained for rat tail collagen in digestion experiments using a 41‐kDa gelatinase activity, isolated from sea urchin eggs. These results identify structural differences between a typical, vertebrate type I fibrillar collagen and an echinoderm collagen which serves as a constituent of a mutable connective tissue. These differences may relate to the functional roles played by collagen in these distinctly different tissues. J. Cell. Biochem. 84: 567–574, 2002. © 2001 Wiley‐Liss, Inc.
Orphan nuclear receptor binding site in the human inducible nitric oxide synthase promoter mediates responsiveness to steroid and xenobiotic ligands
Authors: Toell Andrea , Kröncke Klaus‐Dietrich , Kleinert Hartmut , Carlberg Carsten 
Published: October 2004

AbstractConstitutive androstane receptor (CAR) and pregnane X receptor (PXR) are members of the nuclear receptor superfamily that regulate target gene transcription in a ligand‐dependent manner. CAR and PXR have a rather broad, overlapping set of ligands that range from natural steroids to xenobiotics and also recognize similar DNA binding sites, referred to as response elements (REs), primarily in promoter regions of cytochrome P450 (CYP) genes. In this study, a CAR and PXR RE, composed of a direct repeat of two GGTTCA motifs in a distance of 4 nucleotides (DR4), was identified in the promoter of the human inducible nitric oxide (NO) synthase (iNOS ) gene, which is the first nuclear receptor binding site reported for this promoter. In a heterologous promoter context, the DR4‐type sequence also acts as a functional RE for the nuclear receptors for 1α,25‐dihydroxyvitamin D3 (1α,25(OH)2D3) and 3,5,3′‐triiodothyronine (T3), VDR and T3R. However, in a direct competition of CAR, PXR, VDR, and T3R, the PXR‐retinoid X receptor (RXR) complex appears to be the dominant regulator on the iNOS DR4‐type RE. In the natural iNOS promoter context, the DR4‐type RE specifically mediates downregulation of promoter activity by the testosterone metabolite androstanol through CAR‐RXR heterodimers and upregulation by the xenobiotic drug clotrimazole through PXR–RXR heterodimers. These results were confirmed on the level of mRNA expression. Since an iNOS‐induced production of NO is known to influence inflammation and apoptosis, a CAR‐ and PXR‐regulated iNOS activity may explain a modulatory effect of steroids and xenobiotics on these cellular processes. J. Cell. Biochem. 85: 72–82, 2002. © 2002 Wiley‐Liss, Inc.
Interaction of the ADP‐ribosylating enzyme from the hyperthermophilic archaeon S. solfataricus with DNA and ss‐oligo deoxy ribonucleotides
Authors: Faraone‐Mennella Maria Rosaria , Piccialli Gennaro , De Luca Paola , Castellano Sabrina , Giordano Anna , Rigano Daniela , De Napoli Lorenzo , Farina Benedetta 
Published: October 2004

AbstractThe DNA‐binding ability of the poly‐ADPribose polymerase‐like enzyme from the extremely thermophilic archaeon Sulfolobus solfataricus was determined in the presence of genomic DNA or single stranded oligodeoxyribonucleotides. The thermozyme protected homologous DNA against thermal denaturation by lowering the amount of melted DNA and increasing melting temperature. The archaeal protein induced structural changes of the nucleic acid by modifying the dichroic spectra towards a shape typical of condensing DNA. However, enzyme activity was slightly increased by DNA. Competition assays demonstrated that the protein interacted also with heterologous DNA. In order to characterize further the DNA binding properties of the archaeal enzyme, various ss‐oligodeoxyribonucleotides of different base composition, lengths (12‐mer to 24‐mer) and structure (linear and circular) were used for fluorescence titration measurements. Intrinsic fluorescence of the archaeal protein due to tryptophan (excitation at 295 nm) was measured in the presence of each oligomer at 60°C. Changes of tryptophan fluorescence were induced by all compounds in the same range of base number per enzyme molecule, but independently from the structural features of oligonucleotides, although the protein exhibited a slight preference for those adenine‐rich and circular. The binding affinities were comparable for all oligomers, with intrinsic association constants of the same order of magnitude (K = 106 M−1) in 0.01 M Na‐phosphate buffer, pH 8.0, and accounted for a “non‐specific” binding protein. Circular dichroism analysis showed that at 60°C the native protein was better organized in a secondary structure than at 20°C. Upon addition of oligonucleotides, enzyme structure was further stabilized and changed towards a β‐conformation. This effect was more marked with the circular oligomer. The analysed oligodeoxyribonucleotides slightly enhanced enzyme activity with the maximal increase of 50% as compared to the control. No activation was observed with the circular oligomer. J. Cell. Biochem. 85: 146–157, 2002. © 2002 Wiley‐Liss, Inc.