bluuebunny/crossref_metadata_2025_split huggingface dataset:
NF‐κB inhibition triggers death of imatinib‐sensitive and imatinib‐resistant chronic myeloid leukemia cells including T315I Bcr‐Abl mutants
Authors: Lounnas Nadia , Frelin Catherine , Gonthier Nadège , Colosetti Pascal , Sirvent Anne , Cassuto Jil‐Patrice , Berthier Fréderic , Sirvent Nicolas , Rousselot Philippe , Dreano Michel , Peyron Jean‐François , Imbert Véronique 
Published: January 2009

AbstractThe Bcr‐Abl inhibitor imatinib is the current first‐line therapy for all newly diagnosed chronic myeloid leukemia (CML). Nevertheless, resistance to imatinib emerges as CML progresses to an acute deadly phase implying that physiopathologically relevant cellular targets should be validated to develop alternative therapeutic strategies. The NF‐κB transcription factor that exerts pro‐survival actions is found abnormally active in numerous hematologic malignancies. In the present study, using Bcr‐Abl‐transfected BaF murine cells, LAMA84 human CML cell line and primary CML, we show that NF‐κB is active downstream of Bcr‐Abl. Pharmacological blockade of NF‐κB by the IKK2 inhibitor AS602868 prevented survival of BaF cells expressing either wild‐type, M351T or T315I imatinib‐resistant mutant forms of Bcr‐Abl both in vitro and in vivo using a mouse xenograft model. AS602868 also affected the survival of LAMA84 cells and of an imatinib‐resistant variant. Importantly, the IKK2 inhibitor strongly decreased in vitro survival and ability to form hematopoietic colonies of primary imatinib resistant CML cells including T315I cells. Our data strongly support the targeting of NF‐κB as a promising new therapeutic opportunity for the treatment of imatinib resistant CML patients in particular in the case of T315I patients. The T315I mutation escapes all currently used Bcr‐Abl inhibitors and is likely to become a major clinical problem as it is associated with a poor clinical outcome. © 2009 UICC
Structural studies of conotoxins
Authors: Daly Norelle L. , Craik David J. 
Published: January 2009

AbstractConotoxins are small disulfide‐rich peptides from the venoms of marine cone snails. They target a variety of ion channels, transporters, and receptors besides the interest in their natural functions in venoms and they are of much interest as drug leads. This short article gives an overview of the structural diversity of conotoxins, and illustrates this diversity with recent selected examples of conotoxin structures. © 2009 IUBMB IUBMB Life, 61(2): 144–150, 2009
Initial investigation of novel human‐like collagen/chitosan scaffold for vascular tissue engineering
Authors: Zhu Chenhui , Fan Daidi , Duan Zhiguang , Xue Wenjiao , Shang Longan , Chen Fulin , Luo Yane 
Published: January 2009

AbstractWith the increasing occurrence of vascular diseases and poor long‐term patency rates of current small diameter vascular grafts, it becomes urgent to pursuit biomaterial as scaffold to mimic blood vessel morphologically and mechanically. In this study, novel human‐like collagen (HLC, produced by recombinant E. coli)/chitosan tubular scaffolds were fabricated by cross‐linking and freeze‐drying process. The scaffolds were characterized by scanning electron microscope (SEM), X‐ray photoelectron spectroscopy (XPS), and tensile test, respectively. Human venous fibroblasts were expanded and seeded onto the scaffolds in the density of 1 × 105 cells/cm2. After a 15‐day culture under static conditions, the cell–polymer constructs were observed using SEM, confocal laser scanning microscopy (CLSM), histological examination, and biochemical assays for cell proliferation and extracellular matrix production (collagen and glycosaminoglycans). Furthermore, the scaffolds were implanted into rabbits' livers to evaluate their biocompatibility. The results indicated that HLC/chitosan tubular scaffolds (1) exhibited interconnected porous structure; (2) achieved the desirable levels of pliability (elastic up to 30% strain) and stress of 300 ± 16 kPa; (3) were capable of enhancing cell adhesion and proliferation and ECM secretion; (4) showed superior biocompatibility. This study suggested the feasibility of HLC/chitosan composite as a promising candidate scaffold for blood vessel tissue engineering. © 2009 Wiley Periodicals, Inc. J Biomed Mater Res 2009
A bovine acellular scaffold for vocal fold reconstruction in a rat model
Authors: Xu Chet C. , Chan Roger W. , Weinberger Debra G. , Efune Guy , Pawlowski Karen S. 
Published: January 2009

AbstractWith a rat model of vocal fold injury, this study examined the in vivo host response to an acellular xenogeneic scaffold derived from the bovine vocal fold lamina propria, and the potential of the scaffold for constructive tissue remodeling. Bilateral wounds were created in the posterior vocal folds of 20 rats, and bovine acellular scaffolds were implanted into the wounds unilaterally, with the contralateral vocal folds as control. The rats were humanely sacrificed after 3 days, 7 days, 1 month, and 3 months, and the coronal sections of their larynges were examined histologically. Expressions of key matrix proteins including collagen I, collagen III, elastin, fibronectin, hyaluronic acid, and glycosaminoglycans (GAGs) were quantified with digital image analysis. Significant infiltration of host inflammatory cells and host fibroblasts in the scaffold implant was observed in the acute stage of wound repair (3 days and 7 days postsurgery). The mean relative densities of collagen I, collagen III, and GAGs in the implanted vocal folds were significantly higher than those in the control after 3 days, followed by gradual decreases over 3 months. Histological results showed that the scaffolds were apparently degraded by 3 months, with no fibrotic tissue formation or calcification. These preliminary findings suggested that the bovine acellular scaffold could be a potential xenograft for vocal fold regeneration. © 2009 Wiley Periodicals, Inc. J Biomed Mater Res, 2010
Enhancing annulus fibrosus tissue formation in porous silk scaffolds
Authors: Chang Godfrey , Kim Hyeon Joo , Vunjak‐Novakovic Gordana , Kaplan David L. , Kandel Rita 
Published: January 2009

AbstractThere is presently no optimal treatment for patients with chronic back pain as a result of degenerative disc disease. Tissue engineering, an annulus fibrosus (AF) construct suitable to repair the damaged AF, is one novel approach to the treatment of this disease. We have previously demonstrated that porous silk scaffolds can support AF cell attachment and extracellular matrix accumulation; however, tissue infiltration and matrix accumulation was not optimal. The purpose of this study was to determine whether the dynamic culture of AF cells seeded into larger average pore size silk scaffolds would improve tissue formation. AF cells were isolated from bovine caudal discs and seeded into porous silk scaffolds and grown in either dynamic or static flow conditions. The cell‐seeded scaffolds were grown for up to 4 weeks and evaluated for cell attachment, gene expression, histological appearance, and matrix accumulation. Dynamic culture improved AF tissue formation as the tissue was more cellular and contained significantly more matrix than that formed in static culture. Spatial distribution of tissue was comparable for static and dynamic culture. Varying scaffold pore sizes (200‐, 600‐, and 1000‐μm pore size) demonstrated that an average pore size of 600 μm resulted in the most uniform tissue distribution with the greatest amount of type I collagen. Our study suggests that dynamic flow conditions and scaffold pore size can affect the formation of engineered AF tissue. © 2009 Wiley Periodicals, Inc. J Biomed Mater Res, 2010
Bone remodeling in a new biomimetic polymer‐composite hip stem
Authors: Bougherara Habiba , Bureau Martin N. , Yahia L'Hocine 
Published: January 2009

AbstractAdaptive bone remodeling is an important factor that leads to bone resorption in the surrounding femoral bone and implant loosening. Taking into account this factor in the design of hip implants is of clinical importance, because it allows the prediction of the bone‐density redistribution and enables the monitoring of bone adaptation after prosthetic implantation. In this article, adaptive bone remodeling around a new biomimetic polymer‐composite‐based (CF/PA12) hip prosthesis is investigated to evaluate the amount of stress shielding and bone resorption. The design concept of this new prosthesis is based on a hollow substructure made of hydroxyapatite‐coated, continuous carbon fiber (CF)‐reinforced polyamide 12 (PA12) composite with an internal soft polymer‐based core. Strain energy density theory coupled with 3D Finite Element models is used to predict bone density redistributions in the femoral bone before and after total hip replacement (THR) using both polymer‐composite and titanium (Ti) stems. The result of numerical simulations of bone remodeling revealed that the CF/PA12 composite stem generates a better bone density pattern compared with the Ti‐based stem, indicating the effectiveness of the composite stem to reduce bone resorption caused by stress‐shielding phenomenon. This may result in an extended lifetime of THR. © 2009 Wiley Periodicals, Inc. J Biomed Mater Res, 2010
Preparation and in vivo evaluation of apatite/collagen packed composite by alternate immersion method and Newton press
Authors: Taira Masayuki , Nezu Takashi , Sasaki Kaori , Saitoh Setsuo , Kagiya Tadayoshi , Harada Hidemitsu , Takada Yukyo , Araki Yoshima 
Published: January 2009

AbstractFurther development of bio‐compatible, bio‐absorbable, and osteo‐conductive bio‐materials is desired for bone grafts in dental and medical clinics. One candidate material might be a high‐density apatite/collagen composite, which cures relatively large bone defects. To produce such a composite, we freeze‐dried type I collagen solution, cross‐linked the formed sponge by 2 wt % glutaraldehyde, immersed the insoluble sponge in CaCl2 and Na2HPO4 solutions alternately five times, and compacted the sponge by Newton press at 5000 kgf. For comparison, cross‐linked collagen without alternate immersion was also pressed. SEM/EPMA, XRD, and FTIR analyses clarified that alternate immersion successfully coated the collagen sponge with hydroxyapatite. Packed apatite/collagen composite and collagen disks 6 mm in diameter and 0.5 mm in height were implanted in the subperiostea of rabbit tibiae for 2, 4, 8, and 12 weeks to assess bio‐compatibility, bio‐absorbability, and osteo‐conductivity. Histological observations showed that the packed apatite/collagen composite was biocompatible, osteo‐conductive for up to 8 weeks, and largely bio‐absorbed at 12 weeks, while the packed collagen sponge caused an undesirable foreign body reaction, which worsened with the implantation period. The overall findings suggest that this packed apatite/collagen composite might be used as a new bio‐absorbable bone graft material. © 2009 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2009
Cytoprotective effects of the lipoidic‐liquiform pro‐vitamin C tetra‐isopalmitoyl‐ascorbate (VC‐IP) against ultraviolet‐A ray‐induced injuries in human skin cells together with collagen retention, MMP inhibition and p53 gene repression
Authors: Xiao Li , Kaneyasu Kentaro , Saitoh Yasukazu , Terashima Yoichi , Kowata Yasunori , Miwa Nobuhiko 
Published: January 2009

AbstractIrradiation with ultraviolet‐A (UVA) ray at doses of 20–100 J/cm2 diminished the cell viability of human keratinocytes HaCaT and human melanoma cells HMV‐II, both of which were protected by pre‐irradiational administration with the ascorbic acid (Asc) derivative, VC‐IP (2,3,5,6‐O‐tetra‐2′‐hexyldecanoyl‐L‐ascorbic acid; vitamin C‐isopalmityl tetraester), which is the first lipoidic‐liquiform pro‐vitamin C by itself that is materialized by esterization of all four intramolecular hydroxyl groups of an Asc molecule with branched chain fatty groups, resulting in molecular fluidity higher than that of the corresponding straight chains. Irradiation with UVA to HaCaT keratinocytes was shown to cause the formation of 8‐hydroxydeoxyguanosine (8‐OHdG), translocation of phosphatidylserine in the inner layer into the outer layer of cell membrane, and lowering of a mitochondrial membrane potential, all of which were repressed by pre‐irradiational administration with VC‐IP. Expression of p53 gene, another hallmark of UV‐induced DNA damages, was promoted by UVA irradiation to the keratinocytes but also repressed by VC‐IP. Administration with VC‐IP of 10–50 µM to human fibroblasts NHDF achieved the enhancement of collagen synthesis, repression of matrix metalloprotease‐2/9 activity, and increasing of intracellular Asc contents more markedly than that with Asc itself of the same concentrations. Thus UVA‐induced diverse harmful effects could be prevented by VC‐IP, which was suggested to ensue intrinsically from the persistent enrichment of intracellular Asc, through esterolytic conversion of VC‐IP to a free‐form Asc molecule, resulting in relief to UVA‐caused oxidative stress. J. Cell. Biochem. 106: 589–598, 2009. © 2009 Wiley‐Liss, Inc.
In situ indentation of nanoporous gold thin films in the transmission electron microscope
Authors: Sun Ye , Ye Jia , Minor Andrew M. , Balk T. John 
Published: January 2009

AbstractThe mechanical behavior of nanoporous gold was investigated during in situ nanoindentation in the transmission electron microscope. Thin films of nanoporous gold, with ligaments and pores of the order of 10‐nm diameter, offer a highly constrained geometry for deformation and thus provide an opportunity to study the role of defects such as dislocations in the plasticity of nanomaterials. Films ranging in thickness from 75 to 300 nm were indented, while the motion of dislocations and deformation of ligaments were observed in situ. Dislocations were generated and moved along ligament axes, after which they interacted with other dislocations in the nodes of the porous network. For thicker films, the load‐displacement curves exhibited load drops at regular intervals. The question of whether the spacing of these load drops was related to the collapse of pores in the nanoporous films or due to bursts of plasticity within the ligaments was investigated. Additionally, the effect of the indenter displacement rate on the mechanical response of these gold films with nanoscale porosity was investigated. Indentation rates were varied from 1.5 to 30 nm/s. There appears to be a kinetic factor related to dislocation nucleation, where slower displacement rates cause load drops to occur at shorter distance intervals and over longer time intervals. Microsc. Res. Tech., 2009. © 2009 Wiley‐Liss, Inc.
Digital titration: Automated image acquisition and analysis of load and growth of Chlamydophila psittaci
Authors: Beeckman Delphine S.A. , Meesen Geert , Van Oostveldt Patrick , Vanrompay Daisy 
Published: January 2009

AbstractTraditionally, the amount of infective chlamydiae in a given sample is determined by inoculating dilution series into cell cultures and physically counting chlamydial inclusions. This approach is time consuming, tedious, and error prone, mainly when dealing with high titers. Therefore, this paper describes a largely automated technique that was developed to standardize the determination of chlamydial load in vitro. Cells are fixed at 36 h post‐inoculation and bacteria visualized using standard immunological detection methods. Consequently, for 81 microscopic fields, an image is recorded at the interpolated focal plane. These images are then automatically processed using an ImageJ plugin and the obtained results are imported into Excel to determine the number of inclusion forming units per mL in the sample. The main advantage of this technique is that no or minimal sample dilution is required, thus minimizing dilution errors. In addition, this technique was employed during the early, middle and late growth stages of the chlamydial developmental cycle and results correlated well (P < 0.01) with 16S rRNA values from previous experiments, thereby proving its suitability to follow chlamydial growth in vitro. The method described is highly suitable for high throughput titration of cell culture inoculated samples and assessment of possible antichlamydial effects of novel compounds throughout the chlamydial growth cycle. Microsc. Res. Tech., 2009. © 2009 Wiley‐Liss, Inc.
Contribution of the tooth bud mesenchyme to alveolar bone
Authors: Diep Lisa , Matalova Eva , Mitsiadis Thimios A. , Tucker Abigail S. 
Published: January 2009

AbstractThis study highlights the dynamic nature of the mesenchymal cells during tooth development from the bud to the bell stage. Condensing mesenchymal cells, labelled on either side of the developing tooth bud, move toward the presumptive roots forming an arc of cells under the dental papilla. These labelled cells take part in formation of the dental follicle, which contributes to both the tooth and its surrounding periodontium, including the supporting alveolar bone. This study, thus, physically links development of the tooth with the tissue into which it develops. The results obtained clearly indicate that the tooth organ is an entity comprising dental and periodontal tissue. J. Exp. Zool. (Mol. Dev. Evol.) 312B:510–517, 2009. © 2009 Wiley‐Liss, Inc.
In vivo metabolite profile of adult zebrafish brain obtained by high‐resolution localized magnetic resonance spectroscopy
Authors: Kabli Samira , Spaink Herman P. , De Groot Huub J.M. , Alia A. 
Published: January 2009

AbstractPurposeTo optimize high‐resolution MR spectroscopy (MRS) for obtaining neurochemical composition of adult zebrafish brain in vivo.Materials and MethodsA flow‐through setup for supporting MRS of living zebrafish has been designed. In vivo MR microscopy (MRM) images were obtained using a rapid acquisition with relaxation enhancement (RARE) sequence to select a volume of interest. In vivo MR spectra from zebrafish brain were obtained using an optimized point‐resolved spectroscopy (PRESS) sequence preceded by a variable pulse power and optimized relaxation delays (VAPOR) sequence for global water suppression interleaved with outer volume suppression (OVS). In vitro MR spectra in the brain extract were obtained by using correlated spectroscopy (COSY) sequences.ResultsOptimized high‐resolution localized MRS at 9.4T in conjunction with a strong gradient system, efficient shimming, and the water suppression scheme resulted in a reasonable separation of resonances from various metabolites in vivo from a voxel as small as 3.3 μL placed in the zebrafish brain. In addition, more than 14 metabolites were identified in adult zebrafish brain extracts.ConclusionWe have successfully optimized a high‐resolution localized in vivo MRS technique to get access to the zebrafish brain, and obtained for the first time the neurochemical composition of the zebrafish brain. J. Magn. Reson. Imaging 2009;29:275–281. © 2009 Wiley‐Liss, Inc.
T2 relaxometry of normal pediatric brain development
Authors: Leppert Ilana R. , Almli C. Robert , McKinstry Robert C. , Mulkern Robert V. , Pierpaoli Carlo , Rivkin Michael J. , Pike G. Bruce 
Published: January 2009

AbstractPurposeTo establish normal age‐related changes in the magnetic resonance (MR) T2 relaxation time constants of brain using data collected as part of the National Institutes of Health (NIH) MRI Study of Normal Brain Development.Materials and MethodsThis multicenter study of normal brain and behavior development provides both longitudinal and cross‐sectional data, and has enabled us to investigate T2 evolution in several brain regions in healthy children within the age range of birth through 4 years 5 months. Due to the multicenter nature of the study and the extended period of data collection, periodically scanned inanimate and human phantoms were used to assess intra‐ and intersite variability.ResultsThe main finding of this work, based on over 340 scans, is the identification and parameterization of the monoexponential evolution of T2 from birth through 4 years 5 months of age in various brain structures.ConclusionThe exponentially decaying T2 behavior is believed to reflect the rapid changes in water content as well as myelination during brain development. The data will become publicly available as part of a normative pediatric MRI and clinical/behavioral database, thereby providing a basis for comparison in studies assessing normal brain development, and studies of deviations due to various neurological, neuropsychiatric, and developmental disorders. J. Magn. Reson. Imaging 2009;29:258–267. © 2009 Wiley‐Liss, Inc.
Added value of breathhold diffusion‐weighted MRI in detection of small hepatocellular carcinoma lesions compared with dynamic contrast‐enhanced MRI alone using receiver operating characteristic curve analysis
Authors: Xu Peng‐Ju , Yan Fu‐Hua , Wang Jian‐Hua , Lin Jiang , Ji Yuan 
Published: January 2009

AbstractPurposeTo evaluate the added value of single‐breathhold diffusion‐weighted MRI (DWI) in detection of small hepatocellular carcinoma (HCC) lesions (≤2 cm) in patients with chronic liver disease, by comparing the detection sensitivity of combined DWI/conventional dynamic contrast‐enhanced (DCE)‐MRI to that of conventional DCE‐MRI alone.Materials and MethodsA total of 37 patients with chronic liver diseases underwent abdominal MRI at 1.5T, including T1‐weighted imaging (T1WI), T2‐weighted imaging (T2WI), and 2D conventional DCE. For each patient study, axial DWI was performed with a single‐shot echo‐planar imaging (EPI) sequence using a modified sensitivity‐encoding (mSENSE) technique with b‐value of 500 seconds/mm2. A total of 20–24 slices were obtained during a 15–17‐second breathhold. Two observers independently interpreted the combined DWI/conventional DCE‐MRI images and the conventional DCE‐MRI images alone in random order. For all small HCC lesions, the diagnostic performance using each imaging set was evaluated by receiver operating characteristic (ROC) curve analysis. Sensitivity and positive predictive values were also calculated and analyzed.ResultsA total of 47 small HCCs were confirmed as final result. The area under the ROC curve (Az) of combined DWI/conventional DCE‐MRI images (observer 1, 0.922; observer 2, 0.918) were statistically higher than those of conventional DCE‐MRI alone (observer 1, 0.809; observer 2, 0.778) for all small HCC lesions (P < 0.01). The lesion detection sensitivities using the combined technique for both observers were significantly higher than those using conventional DCE‐MRI alone (P < 0.01). The sensitivity values for two observers using the combined technique were 97.87% and those using conventional DCE‐MRI alone were 85.11% to 82.98%. The positive predictive values for two observers using the combined imaging technique (97.87%) were slightly higher than those using conventional DCE‐MRI alone (92.86–93.02%), but there was no significant difference between the two imaging sets.ConclusionCombined use of breathhold DWI with conventional DCE‐MRI helped to provide higher sensitivities than conventional DCE‐MRI alone in the detection of small HCC lesions in patients with chronic liver disease. J. Magn. Reson. Imaging 2009;29:341–349. © 2009 Wiley‐Liss, Inc.