bluuebunny/crossref_metadata_2025_split huggingface dataset:
Characteristic genomic imbalances in pediatric pheochromocytoma
Authors: Hering Antje , Guratowska Monika , Bucsky Peter , Claussen Uwe , Decker Jochen , Ernst Guenther , Hoeppner Wolfgang , Michel Susanne , Neumann Hartmut , Parlowsky Thomas , Loncarevic Ivan 
Published: March 2006

AbstractPheochromocytoma (PCC) in children is rare, genetically not well described, and often related to a poor prognosis. We detected genomic imbalances in all 14 tumors from children analyzed by comparative genomic hybridization. A combinatorial loss of chromatin from 3p and 11p was a common feature in 10 of 14 (72%) patients, which was a result of either a loss of a total chromosome 3 and a total chromosome 11 in 6 of 10 patients, or confined deletions of their p arms in 4 of 10 patients. All patients exhibiting a loss of 3p and 11p carried VHL mutations. The VHL mutations were constitutive in 9 cases and somatic and restricted to tumor DNA in the remaining tumor. On the other hand, VHL mutations were absent in 4 patients, 2 who had other familial syndromes (NF1, SDHD) and 2 with unknown etiology. Our data show that the pattern of imbalances in the tumor DNA of PCC patients strongly correlated with an underlying familial VHL mutation. Furthermore, we show that true sporadic PCC is rare in childhood. Thus, children with PCC should be checked for a related predisposing gene. This would also identify familial syndrome patients requiring long‐term monitoring for other syndrome‐related malignancies. © 2006 Wiley‐Liss, Inc.
Correlation of Mississippian (Upper Viséan) foraminiferan, conodont, miospore and ammonoid zonal schemes, and correlation with the Asbian–Brigantian boundary in northwest Ireland
Authors: Cózar P. , Somerville I. D. , Mitchell W. I. , Medina‐Varea P. 
Published: March 2006

AbstractThe microbiota of the upper Viséan (Asbian–Brigantian) rocks in the Lough Allen Basin in northwest Ireland is analysed. The Middle Mississippian sequence studied extends from the upper part of the Dartry Limestone/Bricklieve Limestone formations of the Tyrone Group to the Carraun Shale Formation of the Leitrim Group. The rocks have been traditionally dated by ammonoid faunas representing the B2a to P2c subzones. The Meenymore Formation (base of the Leitrim Group) also contains conodont faunas of the informal partial‐range Mestognathus bipluti zone. The upper Brigantian Lochriea nodosa Conodont Zone was recognized by previous authors in the middle of the Carraun Shale Formation (Ardvarney Limestone Member), where it coincides with upper Brigantian ammonoids of the Lusitanoceras granosus Subzone (P2a). Foraminifera and algae in the top of the Dartry Limestone Formation are assigned to the upper Cf6γ Foraminifera Subzone (highest Asbian), whereas those in the Meenymore Formation belong to the lower Cf6δ Foraminifera Subzone (lower Brigantian). The Dartry Limestone Formation–Meenymore Formation boundary is thus correlated with the Asbian–Brigantian boundary in northwest Ireland. For the first time, based on new data, a correlation between the ammonoid, miospore, foraminiferan and conodont zonal schemes is demonstrated. The foraminiferans and algae, conodonts and ammonoids are compared with those from other basins in Ireland, northern England, and the German Rhenish Massif. Historically, the Asbian–Brigantian boundary has been correlated with several levels within the P1a Ammonoid Subzone. However, the new integrated biostratigraphical data indicate that the Asbian–Brigantian boundary in northwest Ireland is probably located within the B2a Ammonoid Subzone and the NM Miospore Zone, but the scarcity of ammonoids in the Tyrone Group precludes an accurate placement of that boundary within this subzone. Copyright © 2006 John Wiley & Sons, Ltd.
AMP‐dependent protein kinase alpha 2 isoform promotes hypoxia‐induced VEGF expression in human glioblastoma
Authors: Neurath Kathryn M. , Keough Martin P. , Mikkelsen Tom , Claffey Kevin P. 
Published: March 2006

AbstractTumor cells respond to hypoxic stress by upregulating a variety of genes involved in glucose uptake, glycolysis, and angiogenesis, all essential to maintaining nutrient availability and intracellular ATP levels. Adenosine monophosphate‐dependent kinase (AMPK) is a key sensor for cellular homeostasis and is highly sensitive to changes in AMP:ATP ratios. The two catalytic AMPK alpha isoforms (AMPKα1, AMPKα2) were investigated with respect to their expression, cellular distribution, and contribution to VEGF expression under hypoxic stress in human U373 glioblastoma cells. Quantitative real‐time PCR analysis showed AMPKα1 mRNA to be constitutively expressed in normoxia and hypoxia, whereas AMPKα2 mRNA levels were low in normoxia and significantly induced in hypoxia. Fluorescent immunohistochemistry showed that AMPKα2 protein redistributed to the nucleus under hypoxia, whereas AMPKα1 remained distributed throughout the cell. The AMPK chemical inhibitor, 5‐iodotubericidin, effectively repressed the hypoxic induction of VEGF mRNA levels and hypoxia inducible factor‐1 dependent transcription. AMPKα2 repression with RNA interference reduced hypoxia‐induced VEGF mRNA and HIF‐1 transcription, whereas AMPKα1 repression did not. Human glioblastoma cell lines U118 and U138 also showed hypoxia‐induction of AMPKα2 as well as VEGF. Immunohistochemistry analysis of human astrocytoma/glioma samples revealed AMPKα2 present in high grade gliomas within hypoxic pseudopalisading microenvironments. These data suggest that prolonged hypoxia promotes the expression and functional activation of AMPKα2 and VEGF production in glioma cell lines and glioblastoma multiform tumors, thus contributing to tumor survival and angiogenesis in high grade human gliomas. © 2006 Wiley‐Liss, Inc.
Regeneration of whole meniscus using meniscal cells and polymer scaffolds in a rabbit total meniscectomy model
Authors: Kang Sun‐Woong , Sun‐Mi Son , Jae‐Sun Lee , Eung‐Seok Lee , Kwon‐Yong Lee , Sang‐Guk Park , Jung‐Ho Park , Byung‐Soo Kim 
Published: March 2006

AbstractThe current treatments of meniscal lesion in knee joint are not perfect to prevent adverse effects of meniscus injury. Tissue engineering of meniscus using meniscal cells and polymer scaffolds could be an alternative option to treat meniscus injury. This study reports on the regeneration of whole medial meniscus in a rabbit total meniscectomy model using the tissue engineering technique. Biodegradable scaffolds in a meniscal shape were fabricated from polyglycolic acid (PGA) fiber meshes that were mechanically reinforced by bonding PGA fibers at cross points with 75:25 poly(lactic‐co‐glycolic acid). The compressive modulus of the bonded PGA scaffold was 28‐fold higher than that of nonbonded scaffold. Allogeneic meniscal cells were isolated from rabbit meniscus biopsy and cultured in vitro. The expanded meniscal cells were seeded onto the polymer scaffolds, cultured in vitro for 1 week, and transplanted to rabbit knee joints from which medial menisci were removed. Ten or 36 weeks after transplantation, the implants formed neomenisci with the original scaffold shape maintained approximately. Hematoxylin and eosin staining of the sections of the neomenisci at 6 and 10 weeks revealed the regeneration of fibrocartilage. Safranin‐O staining showed that abundant proteoglycan was present in the neomenisci at 10 weeks. Masson's trichrome staining indicated the presence of collagen. Immunohistochemical analysis showed that the presence of type I and II collagen in neomenisci at 10 weeks was similar to that of normal meniscal tissue. Biochemical and biomechanical analyses of the tissue‐engineered menisci at 36 weeks were performed to determine the quality of the tissue‐engineered menisci. Tissue‐engineered meniscus showed differences in collagen content and aggregate modulus in comparison with native meniscus. This study demonstrates, for the first time, the feasibility of regenerating whole meniscal cartilage in a rabbit total meniscectomy model using the tissue engineering method. © 2006 Wiley Periodicals, Inc. J Biomed Mater Res, 2006
Modulating cell adhesion and spreading by control of FnIII7–10 orientation on charged self‐assembled monolayers (SAMs) of alkanethiolates
Authors: Wang Hua , He Yi , Ratner Buddy D. , Jiang Shaoyi 
Published: March 2006

AbstractIn this work, we demonstrate that surface charge can be used to modulate cell adhesion/spreading through the control of the orientation of adsorbed FnIII7–10, which is a cell‐adhesive protein containing RGD residues. Carboxylic acid (COOH) and amine (NH2)‐terminated self‐assembled monolayers (SAMs) of alkanethiolates were used as model negatively and positively charged surfaces, respectively. The adsorbed amount of FnIII7–10 is controlled to be equivalent on both SAMs as confirmed by the adsorption isotherms determined using I125‐radiolabeled FnIII7–10. The binding of a monoclonal antibody specific for the cell‐binding domain of FnIII7–10 was measured by surface plasmon resonance (SPR) to evaluate FnIII7–10 orientations on different SAMs. Results indicate that adsorbed FnIII7–10 on NH2‐SAM has an orientation with more cell‐binding domains accessible than on COOH‐SAM, confirming our predictions from Monte Carlo simulations. Both phase contrast images and Vybrant® MTT cell proliferation assays show that the adhesion/spreading of bovine aortic endothelial cells (BAECs) on the NH2‐SAM is significantly better than that on the COOH‐SAM coated with an equivalent amount of FnIII7–10. These results indicate that surface charge can be used to specifically orient cell adhesive proteins such as FnIII7–10, thus providing a promising strategy to increase the activity of materials incorporating biological moieties. © 2006 Wiley Periodicals, Inc. J Biomed Mater Res, 2006
Effects of in vitro bone formation on the mechanical properties of a trabeculated hydroxyapatite bone substitute
Authors: Kazakia Galateia J. , Nauman Eric A. , Ebenstein Donna M. , Halloran Bernard P. , Keaveny Tony M. 
Published: March 2006

AbstractThis study was designed to test the hypothesis that the mechanical properties of a trabecular bone substitute can be enhanced through in vitro tissue formation. Our specific objectives were to (1) determine the effects of in vitro marrow stromal cell‐mediated tissue deposition upon a trabeculated hydroxyapatite scaffold on the strength and toughness of the resulting bone substitute; and (2) identify and characterize regions of newly deposited matrix and mineral. This work provides a basis for future investigations aimed at transforming a brittle hydroxyapatite scaffold into an osteoinductive, biomechanically functional implant through in vitro bone deposition. As hypothesized, the mechanical properties of the trabecular bone substitutes were significantly enhanced by in vitro tissue formation. As a result of cell seeding and a 5 week culture protocol, mean strength increased by 85% (p = 0.008) and energy to fracture increased by 130% (p = 0.003). Accompanying the enhancement of mechanical properties was the deposition of significant amounts of bone matrix and mineral. Fluorescence imaging, scanning electron microscopy, electron probe microanalysis, and nanoindentation confirmed the presence of bonelike mineral with Ca/P ratio, modulus, and hardness similar to that within human and rat trabecular bone tissue. This new mineralization was found to exist within a newly deposited parallel‐fibered matrix both encasing and bridging between scaffold trabeculae. Taken as a whole, our results establish the feasibility of the production of an osteoinductive hydroxyapatite‐based trabecular bone substitute with mechanical properties enhanced through in vitro bone deposition. © 2006 Wiley Periodicals, Inc. J Biomed Mater Res, 2006
Biodegradable implantable fluconazole delivery rods designed for the treatment of fungal osteomyelitis: Influence of gamma sterilization
Authors: Soriano I. , Martín A. Y. , Évora C. , Sánchez E. 
Published: March 2006

AbstractFluconazole poly(D,L‐lactic) acid (PLA) and poly(L‐lactic) acid (L‐PLA) implantable delivery rods were studied, in vitro and in vivo, as an alternative treatment of fungal osteomyelitis. Implantable rods loaded with 5% fluconazole (FLU) were prepared by the injection‐molding method and sterilized by γ‐irradiation at a dose of 25 kGy. Loading efficiency, physical chemistry (high performance liquid chromatography, X‐ray diffraction, gel permeation chromatography), and in vitro and in vivo release assays were performed to evaluate the novel delivery systems and the sterilization effect on implant characteristics. In spite of polymer degradation after γ‐irradiation, the loading efficiency, chemical stability, and crystallographic structure of FLU were not affected. In vivo studies were carried out in femoral bone marrow of rabbits. Approximately 85 and 80% of the total dose were released within 12 and 4 weeks from PLA and L‐PLA rods, respectively. This showed a faster release rate of FLU in vivo than in vitro, showing almost zero‐order kinetics from PLA rods. © 2006 Wiley Periodicals, Inc. J Biomed Mater Res, 2006
Biodegradability and thermal stabilityof poly(propylene carbonate)/starch composites
Authors: Lu X. L. , Du F. G. , Ge X. C. , Xiao M. , Meng Y. Z. 
Published: March 2006

AbstractPoly(propylene carbonate)/starch (PPC/starch) composites with different starch contents were prepared by melt compounding. The biodegradability of the composites was studied by soil burial for a period of 6 months. FTIR study, thermal analysis and morphology observation indicated clearly the changes of the buried specimens. The weight loss curves and the molecular weight changes of the specimens revealed a three‐stage biodegradation, corresponding to the propagation of microorganisms, the degradation of starch and the degradation of PPC. The experimental results showed that the addition of starch accelerated the degradation of PPC. Specimens with higher starch content exhibited greater weight loss in the second stage and smaller weight loss in the third stage. © 2006 Wiley Periodicals, Inc. J Biomed Mater Res, 2006
Assessment of the effect of a biphasic ceramic on bone response in a rat calvarial defect model
Authors: Develıoğlu Hakan , Saraydin Serpil Ünver , Bolayir Giray , Dupoirieux Laurent 
Published: March 2006

AbstractCalcium phosphate ceramics are being extensively used for orthopedic, periodontal, and dental applications. This study aimed to assess the effect of a biphasic ceramic such as Ceraform® on the osteogenesis in a rat calvarial defect model. 20 Wistar rats were enrolled in the study. Two symmetrical, circular, and 5‐mm‐wide full thickness defects were created in the parietal bones of each animal. The left defect was left empty as a control and the right defect was filled with the particular implant material. Animals were divided into two groups, and 10 animals were sacrificed at month 3 and the rest were sacrificed at month 6. The calvarial specimens were harvested for histological examinations. Defect area samples were stained with hematoxylin–eosin and Masson Thrichrom. A semiquantitative method was used to quantify the bone regeneration. The defects were mostly filled with fibrous connective tissue (3–6 months) in the control site. A loose, fibrovascular tissue was observed at the side of ceraform implantation at month 3. By 6 month, a dense collagenous tissue was observed at the same area. Multinuclear giant cells (MNGC) were detected around the implant bed at month 3 and month 6. No necrosis, tumorigenesis, or infection was observed at the implantation site at any time. There was no statistically meaningful difference regarding bone regeneration between the two defects at each observation period (p>0.05). This study showed that Ceraform® is biocompatible. However, this study indicates that biphasic ceramic do not offer any advantage over hydroxyapatite ceramics. It was also revealed that it had no effects on bone regeneration and that it seemed to be a space maintainer. © 2006 Wiley Periodicals, Inc. J Biomed Mater Res, 2006
Bone morphogenetic protein‐4 enhances vascular endothelial growth factor secretion by human retinal pigment epithelial cells
Authors: Vogt Rhonda R. , Unda Richard , Yeh Lee‐Chuan C. , Vidro Eileen K. , Lee John C. , Tsin Andrew T. 
Published: March 2006

AbstractRetinal pigment epithelial (RPE) cells secrete vascular endothelial growth factor (VEGF), a cytokine known to promote angiogenesis. Results from RNase protection assays (RPAs) show that RPE from non‐diabetic human donors and from adult retinal pigment epithelium‐19 (ARPE‐19) cells expressed significant bone morphogenetic protein‐4 (BMP‐4) message. In addition, ARPE‐19 cells cultured in high glucose (25 mM), compared to those in physiological glucose (5.5 mM) released significantly more BMP‐4 into the conditioned media (CM). However, the effect of BMP‐4 on the release of VEGF by ARPE‐19 cells has not been studied. Accordingly, ARPE‐19 cells were treated with BMP‐4 to determine VEGF secretion. BMP‐4 and VEGF levels in the CM and cell lysates were measured by enzyme‐linked immunosorbent assay (ELISA). Cells treated with exogenous BMP‐4 had higher VEGF in the CM and this treatment effect was dose‐ and time‐dependent, while cell lysates had low levels of VEGF. Addition of cycloheximide (CHX) or actinomycin‐D (ACT) significantly reduced VEGF secretion from cells treated with BMP‐4, suggesting that the BMP‐4‐induced secretion of VEGF requires new RNA and protein synthesis. Our results suggest that BMP‐4 may play a role in the regulation of ocular angiogenesis associated with diabetic retinopathy (DR) by stimulating VEGF release from RPE cells. J. Cell. Biochem. 98: 1196–1202, 2006. © 2006 Wiley‐Liss, Inc.
p21Waf1/Cip1 plays a critical role in modulating senescence through changes of DNA methylation
Authors: Zheng Quan Hui , Ma Li Wei , Zhu Wei Guo , Zhang Zong Yu , Tong Tan Jun 
Published: March 2006

AbstractIt has been reported that genomic DNA methylation decreases gradually during cell culture and an organism's aging. However, less is known about the methylation changes of age‐related specific genes in aging. p21Waf1/Cip1 and p16INK4a are cyclin‐dependent kinase (Cdk) inhibitors that are critical for the replicative senescence of normal cells. In this study, we show that p21Waf1/Cip1 and p16INK4a have different methylation patterns during the aging process of normal human 2BS and WI‐38 fibroblasts. p21Waf1/Cip1 promoter is gradually methylated up into middle‐aged fibroblasts but not with senescent fibroblasts, whereas p16INK4a is always unmethylated in the aging process. Correspondently, the protein levels of DNA methyltransferase 1 (DNMT1) and DNMT3a increase from young to middle‐aged fibroblasts but decrease in the senescent fibroblasts, while DNMT3b decreases stably from young to senescent fibroblasts. p21Waf1/Cip1 promoter methylation directly represses its expression and blocks the radiation‐induced DNA damage‐signaling pathway by p53 in middle‐aged fibroblasts. More importantly, demethylation by 5‐aza‐CdR or DNMT1 RNA interference (RNAi) resulted in an increased p21Waf1/Cip1 level and premature senescence of middle‐aged fibroblasts demonstrated by cell growth arrest and high β‐Galactosidase expression. Our results suggest that p21Waf1/Cip1 but not p16INK4a is involved in the DNA methylation mediated aging process. p21Waf1/Cip1 promoter methylation may be a critical biological barrier to postpone the aging process. J. Cell. Biochem. 98: 1230–1248, 2006. © 2006 Wiley‐Liss, Inc.
The exonuclease ISG20 mainly localizes in the nucleolus and the Cajal (Coiled) bodies and is associated with nuclear SMN protein‐containing complexes
Authors: Espert Lucile , Eldin Patrick , Gongora Céline , Bayard Bernard , Harper Francis , Chelbi‐Alix Mounira K. , Bertrand Edouard , Degols Geneviève , Mechti Nadir 
Published: March 2006

AbstractWe have previously shown that ISG20, an interferon (IFN)‐induced gene, encodes a 3′ to 5′ exoribonuclease member of the DEDD superfamily of exonucleases. ISG20 specifically degrades single‐stranded RNA. In this report, using immunofluorescence analysis, we demonstrate that in addition to a diffuse cytoplasmic and nucleoplasmic localization, the endogenous ISG20 protein was present in the nucleus both in the nucleolus and in the Cajal bodies (CBs). In addition, we show that the ectopic expression of the CBs signature protein, coilin, fused to the red fluorescent protein (coilin‐dsRed) increased the number of nuclear dots containing both ISG20 and coilin‐dsRed. Using electron microcopy analysis, ISG20 appeared principally concentrated in the dense fibrillar component of the nucleolus, the major site for rRNA processing. We also present evidences that ISG20 was associated with survival of motor neuron (SMN)‐containing macromolecular nuclear complexes required for the biogenesis of various small nuclear ribonucleoproteins. Finally, we demonstrate that ISG20 was associated with U1 and U2 snRNAs, and U3 snoRNA. The accumulation of ISG20 in the CBs after IFN treatment strongly suggests its involvement in a new route for IFN‐mediated inhibition of protein synthesis by modulating snRNA and rRNA maturation. J. Cell. Biochem. 98: 1320–1333, 2006. © 2006 Wiley‐Liss, Inc.
Orthogonal group divisible designs of type hn for h ≤ 6
Authors: Zhang Xuebin 
Published: March 2006

AbstractFor the existence problem of OGDDs of type gu, Colbourn and Gibbons settled it with few possible exceptions for each group size g. In this article, we will completely settle it for g ≤ 6. © 2006 Wiley Periodicals, Inc. J Combin Designs
Self‐aggregated nanoparticles composed of periodate‐oxidized dextran and cholic acid: preparation, stabilization and in‐vitro drug release
Authors: Yuan Xu‐Bo , Li Hong , Zhu Xiao‐Xia , Woo Hee‐Gweon 
Published: March 2006

AbstractA novel method was used to synthesize cholic acid hydrophobic‐modified dextrans (CAH–Dex) which form nanoparticles in aqueous solution. The stabilization and drug‐loading of the formed nanoparticles were investigated. Dextran was oxidized by sodium periodate to dextran dialdehyde which was then conjugated with cholic acid hydrazide through an acyl hydrazone linkage. The self‐aggregation behavior of the resulting conjugates was investigated using nuclear magnetic resonance, fluorescence and photo correlation spectrometry. The conjugates were found to have low critical aggregate concentrations (CAC) (0.46–0.96 × 10−2 mg mL−1) which is characteristic, depending on both the oxidization and substitution degrees. Above the CAC the conjugates tend to form nanoparticle aggregates with inner hydrophobic environment. The diameters of the nanoparticles rely on the pH of the medium due to the aldo–enol transition of the dextran dialdehyde. By crosslinking the aldehyde groups located on the surface using adipic dihydrazide, the nanoparticles were obviously stabilized. The drug‐loading and release behavior of the nanoparticles was investigated using indomethacin as a hydrophobic model drug. Copyright © 2006 Society of Chemical Industry
Atom Transfer Radical Polymerization of Styrene and Methyl Methacrylate from Mesoporous Ordered Silica Particles
Authors: Save Maud , Granvorka Gwenaëlle , Bernard Julien , Charleux Bernadette , Boissière Cédric , Grosso David , Sanchez Clément 
Published: March 2006

AbstractSummary: Mesoporous silica was used as substrate for the grafting of alkyl halides initiators. The control over the surface‐initiated polymerization of styrene and MMA, in terms of molar mass and molar mass distribution, was successfully achieved using an ATRP mechanism. The occurrence of the polymerization inside the mesopores was confirmed by thermogravimetric analysis.Transmission electron microscopy and schematic representation of mesoporous silica functionalized by the anchored iniator (left) and the grafted polymer (right).magnified imageTransmission electron microscopy and schematic representation of mesoporous silica functionalized by the anchored iniator (left) and the grafted polymer (right).