bluuebunny/crossref_metadata_2025_split huggingface dataset:
Chondrocyte hypertrophy and apoptosis induced by GROα require three‐dimensional interaction with the extracellular matrix and a co‐receptor role of chondroitin sulfate and are associated with the mitochondrial splicing variant of cathepsin B
Authors: Olivotto Eleonora , Vitellozzi Roberta , Fernandez Patricia , Falcieri Elisabetta , Battistelli Michela , Burattini Sabrina , Facchini Annalisa , Flamigni Flavio , Santi Spartaco , Facchini Andrea , Borzi' Rosa Maria 
Published: November 2006

AbstractCXCR2 ligands contribute to chondrocyte hypertrophy and apoptosis, important determinants in cartilage pathophysiology. We unraveled the kinetics of signaling, biochemical, transcriptional, and morphological events triggered by GROα in human osteoarthritic chondrocytes kept in three‐dimensional culture. p38 MAPK activation was assessed with a highly sensitive ELISA. Effector caspase activation was evaluated by cleavage of a fluorogenic substrate. Gene expression of key markers of hypertrophy (MMP‐13, Runx‐2) and matrix synthesis (aggrecan), and of cathepsin B isoform CB(‐2,3) was evaluated by real time PCR. Occurrence of the morphological markers of apoptosis was investigated by transmission electron microscopy (TEM). GROα led to p38 MAPK activation in passaged chondrocytes cultured in micromass but not as a high‐density monolayer. This caused the downstream triggering of chondrocyte hypertrophy (MMP‐13 and Runx‐2 upregulation, and calcium deposition) and apoptosis/anoikis following concurrence of matrix degrading activity, and inhibition of matrix synthesis which also involved the induction of CB(‐2,3). These phenomena proved to be dependent on the co‐receptor role of sulfated glycosaminoglycans (sGAG) and the activation of p38 MAPK, since they were abrogated either by preincubation with soluble chondroitin‐4 sulfate or p38 MAPK inhibitors. The co‐receptor role of sGAG was further demonstrated by colocalization experiments of these molecules with GROα in the stimulated micromasses. These findings suggest that extracellular matrix exerts a regulatory role in chondrocytes differentiation, and that meaningful investigation of the effects of chemokines on chondrocyte biology requires culture conditions respectful of both the differentiated status of the chondrocytes and of their three‐dimensional interaction with the extracellular matrix. J. Cell. Physiol. 210: 417–427, 2007. © 2006 Wiley‐Liss, Inc.
Assessment of lung development using hyperpolarized helium‐3 diffusion MR imaging
Authors: Altes Talissa A. , Mata Jaime , de Lange Eduard E. , Brookeman James R. , Mugler John P. 
Published: November 2006

AbstractPurposeTo determine whether hyperpolarized helium‐3 (HHe) diffusion MR can detect the expected enlargement of alveoli that occurs with lung growth during childhood.Materials and MethodsA total of 29 normal subjects aged four to 30 years underwent HHe diffusion MR imaging with theb‐value pair 0, 1.6 second/cm2. A second acquisition during a separate breathhold was performed using theb‐value pair 0, 4 second/cm2to evaluate the dependence onb‐value. The mean apparent diffusion coefficient (ADC) and lung volume for each acquisition and each subject was determined.ResultsSubjects as young as four years of age were able to cooperate with the imaging procedure. The mean ADC increased with increasing subject age (r = 0.8;P< 0.001), with a 55% increase in mean ADC from the youngest to oldest subject. Lung volumes measured on MR were highly repeatable for the two HHe MR acquisitions (r = 0.980,P< 0.001). The mean ADC values measured with the two differentb‐value pairs were highly correlated (r = 0.975;P< 0.001), but the higherb‐value pair resulted in slightly lower mean ADCs (P< 0.001).ConclusionHHe diffusion MR appears to detect the expected increase in alveolar size during childhood, and thus HHe MR may be a noninvasive method to assess development of the lung microstructure. J. Magn. Reson. Imaging 2006. © 2006 Wiley‐Liss, Inc.
Fat suppression with spectrally selective inversion vs. high spectral and spatial resolution MRI of breast lesions: Qualitative and quantitative comparisons
Authors: Fan Xiaobing , Abe Hiroyuki , Medved Milica , Foxley Sean , Arkani Sanaz , Zamora Marta A. , Olopade Olufunmilayo I. , Newstead Gillian M. , Karczmar Gregory S. 
Published: November 2006

AbstractPurposeTo compare conventional fat‐suppressed MR images of the breast to images derived from high spectral and spatial resolution MR data. Image quality and the level of fat suppression are compared qualitatively and quantitatively.Materials and MethodsWomen with suspicious breast lesions found on X‐ray mammography were imaged on 1.5 Tesla GE SIGNA scanners. High spectral and spatial resolution (HiSS) data were acquired using echo‐planar spectroscopic imaging. Images with intensity proportional to the water signal peak height in each voxel were synthesized. Conventional fat‐suppressed images were acquired using a frequency selective inversion method. The experimental (HiSS) and conventional images were compared by experienced radiologists to evaluate the quality of fat suppression. In addition, fat suppression and image quality were evaluated quantitatively.ResultsFat suppression, tumor edge delineation, lesion conspicuity, and image texture were improved in the peak height images derived from HiSS data.ConclusionThe results demonstrate that the water peak height images obtained from HiSS data potentially could improve the quality of fat suppression, detection and diagnosis of breast cancer. HiSS allowed detection of lesions and evaluation of lesion morphology prior to contrast media injection. J. Magn. Reson. Imaging 2006. © 2006 Wiley‐Liss, Inc.
Open‐chest 31P magnetic resonance spectroscopy of mouse heart at 4.7 Tesla
Authors: Lee Joseph , Hu Qingsong , Nakamura Yasuhiro , Wang Xiaohong , Zhang Xiaoliang , Zhu Xiaohong , Chen Wei , Yang Qinglin , Zhang Jianyi 
Published: November 2006

AbstractPurposeTo develop a rapid, robust, and accurate method for assessing myocardial energetics in mice and demonstrate its applicability to mouse models of acquired and genetic heart disease.Materials and MethodsWe combined surface coil localization (10‐mm diameter, tunable between 1H and 31P, using adiabatic half‐passage radiofrequency pulses) and surgery (electrocautery removal of anterior chest wall) to create an open‐chest method for acquiring in vivo 31P nuclear magnetic resonance (NMR) cardiac spectra from mice at 4.7T within 12 minutes. Normal BALB/c mice, BALB/c with myocardial infarction (MI), cardiomyocyte‐restricted peroxisome proliferator‐activated receptor‐delta knockout (KO) (CR‐PPARd–/–) and control loxP‐flanked Ppard (Ppardflox/flox) mice were examined.ResultsThe mean phosphocreatine (PCr)/adenosine triphosphate (ATP) ratios in control BALB/c mice, BALB/c MI mice, Ppardflox/flox mice, and PPAR‐δ KO mice were 2.13 ± 0.09 (N = 11), 1.35 ± 0.07 (N = 9, P < 0.001 vs. BALB/c control), 1.92 ± 0.09 (N = 5), and 1.31 ± 0.12 (N = 5, P < 0.005 vs. Ppardflox/flox control), respectively. The significant depression of myocardial PCr/ATP we observed in these genetic/acquired models of heart disease was in accord with previous data from analogous large animal models. No NMR signal contamination from chamber blood or adjacent skeletal muscle was identified.ConclusionThis new technique provides cardiac 31P spectra suitable for accurate quantitative analysis in a relatively short acquisition time, is suitable for terminal studies of mouse myocardial energy metabolism, and could be installed in virtually any NMR laboratory to study myocardial energetics in numerous mouse models of human heart disease. J. Magn. Reson. Imaging 2006. © 2006 Wiley‐Liss, Inc.
Estimation of pulse wave velocity in main pulmonary artery with phase contrast MRI: Preliminary investigation
Authors: Peng Hsu‐Hsia , Chung Hsiao‐Wen , Yu Hsi‐Yu , Tseng Wen‐Yih I. 
Published: November 2006

AbstractPurposeTo assess the feasibility and reproducibility of a noninvasive MRI method to measure pulse wave velocity (PWV) in the main pulmonary artery (MPA).Materials and MethodsA total of 17 subjects without history of pulmonary diseases (38.2 ± 18.4 years) participated in this study. Series of MR velocity maps of the MPA were acquired at 2 cm above the pulmonary valves using a two‐dimensional phase‐contrast sequence. Effective temporal resolution was 11 msec after interleaving two dynamic series with different values of electrocardiograph (ECG) trigger delay. PWV was derived as the rate of MPA flow variations per unit change in MPA cross‐sectional area, during early systole. Seven healthy subjects underwent three repetitive examinations to investigate intrascan and interscan reproducibility.ResultsFlow vs. area was highly linear in the MPA during early systole, with Pearson's coefficients ranging from 0.982 to 0.999, rendering derivation of PWV with little difficulty. Average value of PWV in MPA was 1.96 ± 0.27 m/second, in good agreement with literature values measured using invasive means. The percentage intra‐ and interscan differences were 5.46% and −10.86%, respectively.ConclusionPhase‐contrast MRI to noninvasively measure PWV in the MPA is feasible with good reproducibility. J. Magn. Reson. Imaging 2006. © 2006 Wiley‐Liss, Inc.
Evaluation of carotid artery wall volume measurement using novel semiautomated analysis software
Authors: Varghese Anitha , Merrifield Robert D. , Crowe Lindsey A. , Collins Steven A. , Keenan Niall G.J. , Firmin David N. , Yang Guang Zhong , Pennell Dudley J. 
Published: November 2006

AbstractPurposeTo evaluate semiautomated analysis software for measuring the total carotid arterial wall volume (TWV) as a measure of atheroma burden.Materials and MethodsSemiautomated‐software and manual analyses of TWV measured by cardiovascular magnetic resonance (CMR) were compared in two phantom models, 10 subjects with no known carotid artery disease, and eight subjects with known carotid disease. The subjects were scanned twice for reproducibility.ResultsIn subjects with no known carotid disease, semiautomated analysis of 98% of slices showed an improved interstudy coefficient of variation (COV) compared to manual analysis of 50% of slices (4.0% vs. 6.2%, P = 0.02). The proportion of matched cross‐sectional slices usable for TWV measurement was superior (99% vs. 49%, P = 0.005) and the median analysis time was shorter (31 minutes vs. 90 minutes, P < 0.001) using the semiautomated software. In subjects with known carotid disease, semiautomated (99% of slices) and manual (56% of slices) analyses had comparable interstudy COVs (4.1% vs. 3.9%, P = 0.01). However, the proportion of matched cross‐sectional slices usable for TWV measurement was greater using semiautomated contouring (96% vs. 56%, P = 0.01).ConclusionCarotid CMR measurement of TWV using novel semiautomated analysis software shows good reproducibility, enables greater coverage of arterial vessel wall length, and is considerably faster compared to manual contouring. J. Magn. Reson. Imaging 2006. © 2006 Wiley‐Liss, Inc.
In Situ AP/MALDI‐MS characterization of anchored matrix metalloproteinases
Authors: Grasso Giuseppe , Fragai Marco , Rizzarelli Enrico , Spoto Giuseppe , Yeo Kwon Joo 
Published: November 2006

AbstractSeveral different procedures are available for the immobilization of proteins on solid supports, as many advantages derive from this approach, such as the possibility to develop new protein solid‐state assays. Enzymes that are anchored on gold surfaces can interact with several different molecules in a tag‐free environment, opening the way to surface plasmon resonance (SPR) investigations. Nevertheless, it is often important to know the identity of the affinity‐retained analyte, and mass spectrometric analysis, via its unique molecular mass identification, represents a very valuable complementary method.There are many pieces of evidence to suggest that matrix metalloproteinases (MMPs) are involved in normal and pathological processes, including embryogenesis, wound healing, inflammation, arthritis and cancer, but presumably also exhibiting other functions. The search for new inhibitors of MMPs has prompted research towards the development of new solid‐state assays for the rapid evaluation of MMP activity. We have already reported the possibility of measuring the activity of MMP‐1 anchored on solid support by coupling SPR with ESI‐MS analysis. In this work, we show the in situ atmospheric pressure (AP) MALDI‐MS characterization of MMPs anchored on a gold chip with known surface coverage. The study extends the MS analysis to different proteins, and sequence coverage is reported for different digestion and MS procedures. Copyright © 2006 John Wiley & Sons, Ltd.
Hexyl‐aminolevulinate‐mediated photodynamic therapy: How to spare normal urothelium. An in vitro approach
Authors: Vaucher Laurent , Jichlinski Patrice , Lange Norbert , Ritter‐Schenk Céline , van den Bergh Hubert , Kucera Pavel 
Published: November 2006

AbstractBackground and ObjectivesPhotodynamic therapy (PDT) of superficial bladder cancer may cause damages to the normal surrounding bladder wall. Prevention of these is important for bladder healing. We studied the influence of photosensitizer concentration, irradiation parameters, and production of reactive oxygen species (ROS) on the photodynamically induced damage in the porcine urothelium invitro. The aim was to determine the threshold conditions for the cell survival.MethodsLiving porcine bladder mucosae were incubated with solution of hexylester of 5‐aminolevulinic acid (HAL). The mucosae were irradiated with increasing doses and cell alterations were evaluated by scanning electron microscopy and by Sytox green fluorescence. The urothelial survival score was correlated with Protoporphyrin IX (PpIX) photobleaching and intracellular fluorescence of Rhodamine 123 reflecting the ROS production.ResultsThe mortality ratio was dependent on PpIX concentration. After 3 hours of incubation, the threshold radiant exposures for blue light were 0.15 and 0.75 J/cm2 (irradiance 30 and 75 mW/cm2, respectively) and for white light 0.55 J/cm2 (irradiance 30 mW/cm2). Photobleaching rate increased with decreasing irradiance. Interestingly, the DHR123/R123 reporter system correlated well with the threshold exposures under all conditions used.ConclusionsWe have determined radiant exposures sparing half of normal urothelial cells. We propose that the use of low irradiance combined with systems reporting the ROS production in the irradiated tissue could improve the in vivo dosimetry and optimize the PDT. Lasers Surg. Med. © 2006 Wiley‐Liss, Inc.
Ex vivo imaging of chronic total occlusions using forward‐looking optical coherence tomography
Authors: Munce Nigel R. , Yang Victor X.D. , Standish Beau A. , Qiang Beiping , Butany Jagdish , Courtney Brian K. , Graham John J. , Dick Alexander J. , Strauss Bradley H. , Wright Graham A. , Vitkin I. Alex 
Published: November 2006

AbstractBackground and ObjectivesPercutaneous coronary interventions (PCI) of chronic total occlusions (CTOs) of arteries are more challenging lesions to treat with angioplasty and stenting than stenotic vessels due primarily to the difficulty in guiding the wire across the lesion. Angiography alone is unable to differentiate between the occluded lumen and the vessel wall and to characterize the content of the occlusion. New technologies to aid in interventional guidance are therefore highly desirable. We sought to evaluate tissue characterization in arterial (CTOs) by imaging ex vivo peripheral arterial samples with optical coherence tomography (OCT).Study Design/Materials and MethodsEx vivo arterialsamples were obtained from patients undergoing peripheral limb amputation. Samples were imaged in an enface orientation using an OCT system, enabling sequential acquisition of longitudinal images and volumetric reconstruction of cross‐sectional views of theoccluded arteries. Histology was performed for comparison.ResultsOCT imaging reliably differentiated between the occluded lumen and the underlying arterial wall in peripheral CTOs. OCT correctly identified tissue composition within the CTO, such as the presence of collagen and calcium and was also able to identify intraluminal microchannels.ConclusionsOCT imaging of CTO anatomy and tissue characteristics may potentially lead to substantial improvements in PCI interventions by providing novel guiding capabilities. Lasers Surg. Med. © 2006 Wiley‐Liss, Inc.
Preparation and Properties of Polystyrene/SEBS Blends with Compositional Gradients in Their Sheet Direction
Authors: Agari Yasuyuki , Yamamoto Taichi , Nomura Ryoki 
Published: November 2006

AbstractThere have been a few reports that discussed polymer blends with compositional gradient in their sheet directions. Thus, we discussed the preparation of the graded polystyrene(PS)/styrene‐hydorogenated butadiene‐ styrene block copolymer(SEBS) blend with compositional gradient in their sheet directions, by applying of the solution‐diffusion method. Then, the hardness on the air side surface of the graded blend gradually increased with shifting the measured point from the edge containing lowest PS content. All of the areas, into which the graded blend sheet was divided, were almost equal in length, when total elongation was 6.6 mm. However, the length of the area became longer at the larger SEBS content, when the total elongation was 175 mm. The ratio of the length of the area to that in lowest SEBS content increased gradually with increasing of SEBS content, when the total elongation became over 50 mm. It was considered that this phenomenon occurred, because of the compositional gradient in the PS/SEBS graded blend.
Synthesis of Low Dielectric Constant Polyetherimide Films
Authors: Chen Bor‐Kuan , Fang Yu‐Ting , Cheng Jing‐Ru 
Published: November 2006

AbstractAs the demand for downsizing in microelectronics is increasing, devices require material with lower dielectric constant accordingly. The dielectric constants for most polyimide (PI), including polyetherimide (PEI), films are ∼3.5. In this study, we modified the PEI by incorporating various monomers (fluorinated dianhydride 6FDA and phenylene ether diamines) to reduce the dielectric constant. The dielectric constants of synthesized PEIs decreased with increasing amounts of 6FDA content and phenylene ether units. The Tg decreased gradually with PEI containing longer phenylene ether units, but increased with the content of 6FDA. The thermal decomposition temperatures at 10% weight loss were ∼550 °C, indicating that these PEIs have high thermal stability. Both the tensile strength and the modulus decreased with the PEI containing longer phenylene ether units. The PEI synthesized with 40% 6FDA dianhydride and 1,4‐bis(4‐aminophenoxy)benzene (pBAB) diamine has the lowest dielectric constant of 2.78 at 1 MHz.
Supramolecular Structure of N,N‐Bis(2‐hydroxy‐benzyl)alkylamine: From Hydrogen Bond Assembly to Coordination Network in Guest Acceptance
Authors: Phongtamrug Suttinun , Chirachanchai Suwabun , Tashiro Kohji 
Published: November 2006

AbstractN,N‐Bis(2‐hydroxybenzyl)alkylamine (HBA) was described as a model to simplify the supramolecular system of polybenzoxazines. The single crystal X‐ray analysis revealed that HBA forms a dimeric assembly based on its simultaneous inter‐ and intramolecular hydrogen bond network. When the HBA accepted the copper ion, the dimeric assembly HBA changed its primary hydrogen bond network to charge transfer coordination as clarified by the single crystal analysis as well as the superimposed structure based on DMol3 calculation. The supramolecular structure of HBA and copper also exhibited the role of solvent molecules in the packing structure which is a rare example showing the host accepts not only the metal ions but also the neutral molecules in the same time. The cyclization of HBA with esters or ethers to macrocyclic compounds was also an important model reaction to show how the backbone molecules self‐stabilized with the hydrogen bond network initiate the simple, effective and efficient macrocyclic reaction.
Paclitaxel‐Warfarin Interaction in Solution
Authors: Wunderlich Stefan , Zähres Manfred , Jo Byung‐Wook , Hess Michael 
Published: November 2006

AbstractInteractions of a water‐soluble paclitaxel‐polymer conjugate were investigated in aqueous buffer solutions and in the solid state in the presence of model proteins that are abundant in blood serum (bovine serum albumin and human serum albumin). Studies of the intrinsic fluorescence of albumins and extrinsic fluorescence of the albumin/warfarin complex and MALDI‐TOF spectra proved significant interactions of the drug conjugate with the model proteins and warfarin.
RTL Investigation on the Radiochemical Oxidation of Polyolefins
Authors: Jipa Silviu , Zaharescu Traian , Kappel Wilhelm , Setnescu Radu , Oros Cǎlin 
Published: November 2006

AbstractHigh energy radiation causes deep modification of exposed polymers. In the irradiated polymers, the main macroscopic process is the formation of free radicals. The “cooled” electron distribution at the temperature of liquid nitrogen will develop the existence of various electron gaps with certain depths by smooth heating up to room temperature. In this paper, low density polyethylene, high density polyethylene and polypropylene were subjected to the action of gamma rays for causing structural modifications. The glow curves of quantum emission were recorded by slow heating from 106 to 286 K. The characteristic shoulders were obtained, which were ascribed to various electron traps consisting of unsaturation or carbonyl groups. For depicting the influence of molecular structures, the influence of CH3 number/100 carbon atoms on the intensity of radiothermoluminescence (RTL) signal was studied on three types of LDPEs. A sharp decrease of maximum RTL intensity at advanced branching was pointed out. A mechanism of RTL emission is based on the present measurements.
Crystal Transformation and Development of Tensile Properties upon Drawing of Poly(L‐lactic acid) by Solid‐State Coextrusion: Effects of Molecular Weight
Authors: Sawai Daisuke , Yokoyama Takafumi , Kanamoto Tetsuo , Sungil Moon , Hyon Suong‐Hyu , Myasnikova Liuba P. 
Published: November 2006

AbstractMelt‐crystallized films of poly(L‐lactic acid) (PLLA) with Mv in the range of 3.8 ∼ 46 × 104 consisting of α‐form crystals were uniaxially drawn by solid‐state coextrusion. The effects of Mv, extrusion draw ratio (EDR), and extrusion temperature (Text) on the crystal/crystal transformation from α‐ to β‐form crystals and the resultant tensile properties of drawn products were studied. The crystal transformation proceeded with EDR and more rapidly for the higher Mv's. Furthermore, the crystal transformation proceeded most rapidly with EDR at a Text around 130 °C, independently of the Mv's. As a result of the optimum combination of processing variables influencing the the crystal transformation (Mv, Text, and drawability), highly oriented films consisting of β‐form crystals alone were obtained by coextrusion of higher Mv samples at Text's slightly below the melting temperature (150 ∼ 170 °C) and at higher EDR's > 11. Both the tensile modulus and strength increased rapidly with EDR. The modulus at a given EDR was slightly higher for the samples with higher Mv's. In contrast, the strength at a given EDR was remarkably higher for the higher M
v's. The highest tensile modulus of 8.0 GPa and strength of 500 MPa were obtained with the sample of the highest Mv of 46 × 104 coextruded at 170 °C to the highest EDR of 14.