bluuebunny/crossref_metadata_2025_split huggingface dataset:
Evaluation of MDM2 and CDK4 amplification by real‐time PCR on paraffin wax‐embedded material: a potential tool for the diagnosis of atypical lipomatous tumours/well‐differentiated liposarcomas
Authors: Hostein I , Pelmus M , Aurias A , Pedeutour F , Mathoulin‐Pélissier S , Coindre JM 
Published: December 2003

AbstractAtypical lipomatous tumours/well‐differentiated liposarcomas and dedifferentiated liposarcomas are characterized by 12q13–15 region amplification. In contrast, this molecular event has not been reported in benign lipomas. Within the 12q13–15 chromosomal region, the MDM2, SAS, HMGA2, and CDK4 genes are the most frequent targets of amplification. A series of lipomas (36 cases) and liposarcomas (48 cases) was analysed for MDM2 and CDK4 gene amplification by real‐time PCR. MDM2 and CDK4 gene amplification was detected in 2.8% and 5.6% of lipomas and 98.2% and 82.4% of liposarcomas, respectively. Moreover, co‐amplification of the two genes as well as a higher‐level amplification was observed more frequently in dedifferentiated liposarcomas than in atypical lipomatous tumours/well‐differentiated liposarcomas. Real‐time PCR proved to be a fast and reliable method to characterize lipomas and liposarcomas by quantification of MDM2 and CDK4 gene amplification. It is applicable to paraffin wax‐embedded tissues and could be useful when histological diagnosis is difficult. Copyright © 2004 John Wiley & Sons, Ltd.
A fluid cover medium provides superior morphology and preserves RNA integrity in tissue sections for laser microdissection and pressure catapulting
Authors: Micke Patrick , Bjørnsen Tone , Scheidl Stefan , Strömberg Sara , Demoulin Jean‐Baptiste , Ponten Fredrik , Östman Arne , Lindahl Per , Busch Christer 
Published: December 2003

AbstractLaser microdissection and pressure catapulting has become a powerful tool to obtain homogeneous cell populations from tissue samples in nearly all fields of biomedical research. The isolated cells can be subsequently used for the analysis of proteins, DNA or RNA. However, the method requires physical access to the tissue surface and the sections therefore need to be air‐dried and uncovered. The consequence is poor morphology, which severely reduces the potential of the technique, especially in non‐homogeneous tissues or tissues with infiltrating immune cells. To overcome this limitation, a fluid cover medium was developed and the effects on frozen and paraffin wax‐embedded tissue morphology were evaluated. The cover medium improved the morphology such that it was almost comparable to sections overlaid with glass coverslips. Moreover, the laser microdissection procedure was facilitated, since the medium allowed larger areas of tissues to be laser pressure‐catapulted. Neither the isolation of proteins nor the extraction of genomic DNA was adversely affected by the use of the fluid cover medium. No significant differences in RNA quantity and integrity were detected by TaqMan real‐time PCR for GAPDH, and microchip electrophoresis, between covered and uncovered tissue sections. In conclusion, this method provides considerably improved morphology for laser microdissection and pressure catapulting techniques without affecting RNA‐dependent downstream applications. This not only facilitates established procedures, but will also extend the application to tissues that require superior morphological resolution. Copyright © 2004 John Wiley & Sons, Ltd.
Fibroblast growth factor 2 induces differentiation and apoptosis of Askin tumour cells
Authors: Kim Min‐Suk , Kim Chong Jai , Jung Hyun Sook , Seo Mi Ran , Juhnn Yong‐Sung , Shin Hee Young , Ahn Hyo Seop , Thiele Carol J , Chi Je G 
Published: December 2003

AbstractPeripheral primitive neuroectodermal tumour (PNET)/Ewing's sarcoma (ES) and neuroblastoma (NB) are related tumours of neural crest origin with primitive neural characteristics. Fibroblast growth factor 2 (FGF2) is a critical signalling molecule for primitive neural crest cells. The treatment of NB cells with FGF2 variably affects biological characteristics such as growth and differentiation, while in PNET/ES, FGF2 predominantly induces apoptosis. The JK‐GMS Askin tumour cell line can be induced to differentiate upon treatment with nerve growth factor (NGF), indicating the integrity of the cellular machinery necessary for differentiation. The present study assesses whether FGF2 can induce differentiation in JK‐GMS cells. JK‐GMS cells expressed high‐affinity FGF receptors (FGFRs), and treatment with FGF2 induced phosphorylation of FGFR1 together with activation of extracellular signal‐regulated kinases (ERK1/ERK2) and c‐Jun N‐terminal kinase (JNK). Subsequent biological effects were growth inhibition, neuronal differentiation, and apoptosis, and these changes were associated with increased expression of neurofilaments, reduction of c‐myc and bcl‐2 expression, and activation of caspase 3. Treatment of the cells with a specific inhibitor of the MAPK/extracellular signal‐regulated kinase (MEK)‐1, PD98059, predominantly inhibited the effects of FGF2 on growth, differentiation, and apoptosis, while an inhibitor of JNK reduced apoptosis, indicating that the ERK1/2 and JNK pathways are critical components of FGF2‐mediated effects in JK‐GMS cells. Additional comparative analyses of FGF2‐mediated effects in two ES cell lines (CADO‐ES, RD‐ES) and a PNET cell line (SK‐N‐MC) showed pronounced differentiation in SK‐N‐MC, but not in CADO‐ES or RD‐ES cells. This study demonstrates that FGF2 can induce neuronal differentiation of PNET including Askin tumour. These findings clearly indicate that the FGF2‐mediated signalling pathway plays a critical role in controlling the major properties of PNET cells and may provide a potential therapeutic target for PNET. Copyright © 2004 John Wiley & Sons, Ltd.
Expression of cartilage growth plate signalling molecules in chondroblastoma
Authors: Romeo S , Bovée JVMG , Jadnanansing NAA , Taminiau AHM , Hogendoorn PCW 
Published: December 2003

AbstractChondroblastoma (CB) is a rare benign tumour (<1% of all bone tumours) involving epiphyseal long bones (male : female 1.5 : 1). During development, and in the postnatal period, IHh/PTHrP and FGF signalling molecules control the space and timing of chondrocyte differentiation. Considering the close relationship of CB with the growth plate (age and location), the expression of proteins involved in epiphyseal growth regulation was studied. Twelve cases of CB were retrieved. Immunohistochemistry was performed using antibodies against fibroblast growth factor‐2 (FGF‐2), fibroblast growth factor receptor‐1 (FGFR‐1), FGFR‐3, bcl‐2, p21, parathyroid hormone‐related peptide (PTHrP), and parathyroid hormone‐related peptide receptor (PTHR1). Three observers evaluated haematoxylin and eosin (H&E)‐stained and immunostained slides independently. Semi‐quantitative estimation of the matrix, the type of matrix, and immunostaining was performed. Cellular and matrix‐rich areas were evaluated separately. Diverse amounts and types of matrix were present in different tumours, as well as within individual tumours. Signalling molecules were expressed in 50–100% of the cases. Higher levels of expression were found in cellular areas than in matrix‐rich areas, especially for PTHR1, bcl‐2, and FGFR‐3. CB is an unusual entity affecting specific sites, showing that both IHh/PTHrP and FGF signalling are active. Higher expression was found in cellular than in matrix‐rich areas, as in the proliferating/pre‐hypertrophic growth plate zone in comparison with the hypertrophic/calcifying zone. Previous studies have shown the same molecules to be expressed with a similar pattern in chondrosarcomas. The sum of the evaluated features indicates that CB is a neoplasm originating from a mesenchymal cell committed towards chondrogenesis via active growth plate signalling pathways. Copyright © 2004 John Wiley & Sons, Ltd.
Hypertrophic scar formation is associated with an increased number of epidermal Langerhans cells
Authors: Niessen Frank B , Schalkwijk Joost , Vos Hans , Timens Wim 
Published: December 2003

AbstractThe exact pathogenesis of hypertrophic scar and keloid formation is still unknown and a good therapy to prevent or treat these scars is lacking. Because immunological processes seem to be important in excessive scar formation, immunological cells and parameters were studied in a standardized breast reduction wound‐healing model in the present study. Standardized scar samples were taken from infra‐mammary breast reduction scars, 3 and 12 months following surgery. The samples were investigated for their number of mast cells, Langerhans cells, T‐lymphocytes, and macrophages, and the presence of interleukin‐4 (IL‐4) and counter‐regulating interferon‐gamma (γ‐IFN), in relation to the scar's clinical appearance—normal or hypertrophic. In this study, hypertrophic scar formation was significantly associated with an increased number of epidermal Langerhans cells (p = 0.0001) and significantly (p < 0.05) increased expression of epidermal IL‐4. No relationship was found between mast cell, T‐lymphocyte and macrophage numbers or γ‐IFN staining and the formation of normal or hypertrophic scars. These results, combined with previous observation of abnormal keratinocyte behaviour in this context, indicate that the epidermal immune barrier plays an important role in the development of hypertrophic scars. Copyright © 2003 John Wiley & Sons, Ltd.
Human papillomavirus integration: detection by in situ hybridization and potential clinical application
Authors: Evans Mark F , Cooper Kumarasen 
Published: December 2003

AbstractHuman papillomaviruses (HPVs) are accepted as a necessary cause of cervical neoplasia. However, the benefits of testing simply for high‐risk HPV types are limited because of their high prevalence in intraepithelial lesions of all grades, the majority of which regress if left untreated. One factor considered to be of key importance for the progression of intraepithelial lesions to invasive disease is integration of HPV into the host cell genome. Although questions remain about the prevalence of integration amongst pre‐invasive lesions, sensitive in situ hybridization techniques utilizing tyramide reagents may aid determination of the significance of HPV infection by enabling routine detection of both high‐risk HPV and its physical status. This will provide important data relevant not only to our understanding of the biology of HPV‐associated neoplasia, but also potentially to clinical testing for HPV. Copyright © 2003 John Wiley & Sons, Ltd.
Inversion and interpretation of two‐dimensional geoelectrical measurements for detecting permafrost in mountainous regions
Authors: Hauck Christian , Mühll Daniel Vonder 
Published: December 2003

AbstractThe use of tomographic geoelectrical measurements for the detection of ground ice occurrences in mountainous regions is evaluated. Because isolated ground ice occurrences in a warming climate may be subject to rapid thawing, they present a future hazard in the context of thawing‐permafrost‐induced landslides and rockfalls. Isolated permafrost occurrences are difficult to detect with commonly used one‐dimensional sounding techniques, as plane‐layer approximations for the inversion are often invalid. Therefore, recently developed two‐dimensional tomographic inversion schemes are used to yield realistic near‐surface geological models. The method is applied to various types of permafrost occurrences in the European Alps. The influence of topography, measurement geometry and different inversion parameters are discussed. In addition, complimentary seismic survey results are used to exclude the possibility of air‐filled cavities, which exhibit similarly high resistivities as ground ice occurrences. The results show a large variety of influencing parameters which have to be considered in resistivity inversion and interpretation. Copyright © 2003 John Wiley & Sons, Ltd.
Imaging periglacial conditions with ground‐penetrating radar
Authors: Moorman Brian J. , Robinson Stephen D. , Burgess Margo M. 
Published: December 2003

AbstractThree important parameters that need to be quantified for many permafrost studies are the location of ice in the ground, the position of thermal interfaces, and spatial variations of the water content in the active layer. The data from over 100 investigations in permafrost regions demonstrate that ground‐penetrating radar (GPR) offers an effective way to measure these parameters at a scale appropriate for many process and geotechnical studies. Horizontal to gently‐dipping interfaces between unfrozen and frozen subsurface zones (such as at the base of the active layer or a suprapermafrost talik) were repeatedly detected by GPR and indicated by strong, laterally‐coherent reflections. Coherent reflections are not generated by steeply dipping thermal interfaces (greater than 45°). However, the transition from frozen to unfrozen ground can frequently be located from the radar‐stratigraphic signatures of the two units. The radar‐stratigraphic signature of excess ice in the subsurface is determined by the size of the body. Ice lenses that are smaller than the resolution of the GPR system frequently can be detected and are represented by chaotic or hyperbolic reflections, while the size of larger ice units can be resolved and is defined by distinct laterally‐coherent reflection patterns. This enables the delineation of the vertical and lateral extent of massive ice bodies, and their structural setting. By making precise measurements of the direct ground wave velocity, the water content in the near‐surface can be determined for uniform soils. It is demonstrated that by collecting a grid of GPR data the lateral variations in active‐layer water content can then be estimated. Copyright © 2003 John Wiley & Sons, Ltd.
Determination of frozen soil thermal properties by heated needle probe
Authors: Putkonen Jaakko 
Published: December 2003

AbstractDetermination of the in situ thermal properties of ice‐bearing frozen soil by a two‐prong heated needle probe has traditionally been confounded by the energy consumption and release resulting from the melting and re‐freezing of soil ice. A two‐dimensional soil thermal model that accounts for soil unfrozen water and phase change was used to analyse data from the laboratory and a field site in Spitsbergen. A close correspondence was found between modelled and observed thermal behaviour of the probe. The thermal model highlighted the unsuitability of the probe for determining the thermal properties for ice‐bearing frozen soil at temperatures approximately between −10 °C and 0 °C by standard solver software that does not account for melting of soil ice. The model shows that a heated needle probe can generally be used to determine the soil thermal properties for soil at or below −10 °C. For most soils the thermal properties vary only marginally between about −10 and −2 °C and therefore the thermal properties that are determined for a particular soil at temperature below −10 °C generally apply also to soils that are at temperatures between −10 and −2 °C. Copyright © 2003 John Wiley & Sons, Ltd.
Making the most of new instrumentation
Authors: Thorn Colin E. 
Published: December 2003

AbstractThe paper presents the view that new instrumentation needs to fuel, but also serve rather than dominate, development of theory in periglacial geomorphology. The variety of periglacial environments, the variable nature of the spatial and temporal signals within periglacial environments, and the scale limitations inherent to instrumental investigations, all combine to focus attention on small‐scale geomorphological investigations. Integration of such findings, that is scale‐linkage, is a difficult, but essential, task that requires development of rigorous theory which is unlikely to be directly informed by the results of instrumental studies alone. Copyright © 2003 John Wiley & Sons, Ltd.
New Aspects of Impact Reactivity of Polynitro Compounds, Part III. Impact Sensitivity as a Function of the Imtermolecular Interactions
Authors: Zeman Svatopluk , Krupka Miloslav 
Published: December 2003

AbstractPublished data of impact sensitivity of 33 polynitro compounds detected by sound were expressed as the drop energy, Edr, required for 50 percent initiation probability. A logarithmic relationship has been found between the Edr values and heats of fusion of the said compounds. The relationship has been found to be in accordance with the idea concerning the role of plastic deformations of crystal played in the initiation of energetic materials by impact and shock. An analogous application of heats of sublimation has not given convincing results.
Productions of Ultra‐Fine Powders and Their Use in High Energetic Compositions
Authors: Ivanov Yuri F. , Osmonoliev Mirswan N. , Sedoi Valentin S. , Arkhipov Vladimir A. , Bondarchuk Sergey S. , Vorozhtsov Alexander B. , Korotkikh Alexander G. , Kuznetsov Valery T. 
Published: December 2003

AbstractFine and ultra‐fine powders are actively studied in pyrotechnics, explosives and propellants. The important questions are how to produce a powder with specified characteristics and how to use the powder produced.
New Aspects of Impact Reactivity of Polynitro Compounds. Part IV. Allocation of Polynitro Compounds on the Basis of their Impact Sensitivities
Authors: Zeman Svatopluk 
Published: December 2003

AbstractA linear relationship has been found between the drop energies of impact sensitivity detected by sound and the drop energies of “the first reaction” for 28 polynitro compounds. In the sense of this relationship, the compounds studied fall into three classes. The reason of the said diversification lies in the decomposition reaction rate at the temperature of the beginning of their thermolysis. It is stated that some relationship exists between vibrational excitation by impact, on the one hand, and thermal activation of the molecules of energetic materials, on the other one.
Triaminoguanidine Dinitramide, TAGDN: Synthesis and Characterization
Authors: Wingborg Niklas , Latypov Nikolaj V. 
Published: December 2003

AbstractTwo dinitramide salts with very high heat of formation have been identified, i.e. triaminoguanidine dinitramide (TAGDN) and guanylazide dinitramide (GADN). Thermochemical calculations showed that TAGDN‐propellants have a higher impetus than the corresponding GADN‐propellants at a given flame temperature. Due to the fact that a low flame temperature has to be prefered in a gun, TAGDN seems better suited as a component in gun propellants compared to GADN. TAGDN was thus synthesized, analyzed and characterized to determine some of its properties.
Measurement of thermal parameters and mechanical properties of polymers by atomic force microscopy
Authors: Meincken M. , Balk L. J. , Sanderson R. D. 
Published: December 2003

AbstractA novel technique has been developed to determine thermal transitions locally, e.g. the glass transition of polymers, with atomic force microscopy (AFM). The microscope was operated in stationary non‐contact mode, using it like a dynamic mechanical analyser on a molecular scale, thereby measuring the resonance frequency of the AFM cantilever, which oscillates above the sample surface, as a function of temperature. The thermal transitions of the underlying polymer are clearly visible as a change in the resonance frequency. Using the AFM in this mode allows the determination of the thermal properties of a material at a specific spot on the sample on a molecular scale. Measurements were performed on different polymers, polymer blends, structured polymers, layered systems and thin films. Copyright © 2003 John Wiley & Sons, Ltd.
Electron beam effects on diethylsilane‐covered Si(100) surfaces investigated by x‐ray photoelectron spectroscopy
Authors: Wang P. W. , Lozano J. , Kimberlin K. R. , Craig J. H. 
Published: December 2003

AbstractEthylated silanes and germanes are promising candidates for heterojunction atomic layer epitaxy of SiGe devices. However, thermal dissociation of unwanted ligands in the parent molecules usually is not suitable for device fabrication. Hence, alternative means for dissociation employing low thermal budgets are desirable. In this work, an electron beam was used to irradiate diethylsilane (DES)‐covered Si(100) surfaces at 100 K in order to initiate non‐thermal, electron‐driven dissociation and desorption processes in the adsorbed species. Clean Si(100) surfaces were dosed with gas‐phase DES molecules at 100 K followed by irradiation with 600‐eV electrons (current density 5.4 µAcm−2). The effects of electron irradiation were investigated by obtaining x‐ray photoelectron spectra before and after exposing the DES/Si(100) to the electron beam. Shifts in the binding energy of the C 1s photoelectron peak and a decrease in the total surface carbon concentration are indicative of dehydrogenation and removal of carbon species by electron irradiation. Our results suggest the possibility of electron‐beam‐assisted β‐hydride elimination at 100 K as one channel for surface carbon removal. Copyright © 2003 John Wiley & Sons, Ltd.
Electron‐beam‐induced decomposition of trimethylamine on Si(100)‐2 × 1
Authors: Davies B. M. , Craig J. H. 
Published: December 2003

AbstractElectron‐beam‐induced decomposition of trimethylamine ((CH3)3N) adsorbed on the Si(100)‐2 × 1 surface has been investigated using temperature‐programmed desorption, electron‐stimulated desorption, time‐of‐flight mass spectrometry, and x‐ray photoelectron spectroscopy. At issue is the cleavage of C–H bonds vs. cleavage of N–C bonds in the dissociation of trimethylamine (TMA), which is a dative‐bonded adduct on the Si dimer. Methyl groups are cleaved from the adsorbed TMA by electron irradiation. In addition, hydrogen is desorbed from the TMA and/or its fragments, which influences the decomposition of the TMA to smaller adsorbed fragments. The appearance of a thermal desorption peak for mass 42 subsequent to electron irradiation suggests the production of reaction intermediates similar to those reported previously in gas‐phase decomposition of TMA at high temperature. Copyright © 2003 John Wiley & Sons, Ltd.
Annealing of low‐temperature growth in Ag/Si(111) as measured by RHEED spot profile analysis
Authors: Kimberlin K. R. , Rutter G. M. , Nagle L. M. , Roos K. R. , Tringides M. C. 
Published: December 2003

AbstractUltrathin silver films were grown on Si(111) by molecular beam epitaxy and studied using reflective high‐energy electron diffraction. Intensity oscillations were observed showing evidence of layer‐by‐layer growth at 150–170 K. Upon annealing to room temperature, steps of twice the height of a single step appear in the film observed by spot profile analysis of the specular reflection. The full width at half‐maximum (FWHM) of the specular reflection is monitored as the perpendicular component of the scattering vector, Sz, is changed. The periodicity of the FWHM as a function of Sz doubles after annealing, indicating a doubling of the step height on the surface. The data are fitted using a one‐dimensional diffraction model from which a distribution of steps and step heights is obtained. A comparison with other recent annealing measurements in the Ag/Si(111) system is made and discussed in the context of the ‘electronic growth’ model. Copyright © 2003 John Wiley & Sons, Ltd.