bluuebunny/crossref_metadata_2025_split huggingface dataset:
Cell separation between mesenchymal progenitor cells through porous polymeric membranes
Authors: Higuchi Akon , Shindo Yosuke , Gomei Yumiko , Mori Taisuke , Uyama Taro , Umezawa Akihiro 
Published: May 2005

AbstractThis study investigates the separation of two types of marrow stromal cells, KUSA‐A1 osteoblasts and H‐1/A preadipocytes, by filtration through various porous polymeric membranes. It was found that KUSA‐A1 permeates better than H‐1/A cells through 12‐μm polyurethane foaming membranes. This appears to be due to the relatively smaller cell size of KUSA‐A1 cells. In addition, when feed solutions containing suspensions of either cell type or a mixture of the two were used, the permeation ratio was relatively low (< 6%) through polyurethane and surface‐modified polyurethane foaming membranes. It was also found that there was some degree of separation between KUSA‐A1 and H‐1/A cells (separation factor = 1.8) with nylon‐net filter membranes, but no separation was obtained when filters made of nonwoven fabrics or silk screens were used. This ability of the nylon‐net filter membranes to separate the two cell types was due to a sieving effect that results from an optimal pore size. Finally, permeation of a solution of human serum albumin through the membrane following filtration of the cells did not result in a separation of cells in the recovery solution. © 2005 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2005
Quantitative analysis of monomer vapor release from two‐solution bone cement by using a novel FTIR technique
Authors: Merkhan Imad K. , Hasenwinkel Julie M. , Gilbert Jeremy L. 
Published: May 2005

AbstractMethyl methacrylate monomer can evaporate from bone cement to reach cytotoxic levels of concentrations in the implant bed of total joint prosthesis. Therefore, this study was performed by using a novel Fourier transform infrared spectroscopy method to quantify the release of monomer vapor from experimental two‐solution bone cement in vitro during polymerization, to examine the effect of surface area versus cement mass, and to explore the effect of initiation chemistry. The results revealed that monomer vapor release is a surface phenomenon. In addition, initiation chemistry plays a major role in controlling the reaction time, and therefore heat concentration and dissipation, which resulted in a higher absorbance peak as initiation chemicals concentration increased. It was concluded that using the FTIR to monitor MMA vapors is an effective technique to obtain quantitative information about monomer vapor release from bone cements during polymerization and provides insight on the polymerization kinetics of two‐solution acrylic bone cement. © 2005 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2005
Strategies for increasing the efficiency of a genetic algorithm for the structural optimization of nanoalloy clusters
Authors: Lloyd Lesley D. , Johnston Roy L. , Salhi Said 
Published: May 2005

AbstractAn improved genetic algorithm (GA) is described that has been developed to increase the efficiency of finding the global minimum energy isomers for nanoalloy clusters. The GA is optimized for the example Pt12Pd12, with specific investigation of: the effect of biasing the initial population by seeding; the effect of removing specified clusters from the population (“predation”); and the effect of varying the type of mutation operator applied. These changes are found to significantly enhance the efficiency of the GA, which is subsequently demonstrated by the application of the best strategy to a new cluster, namely Pt19Pd19. © 2005 Wiley Periodicals, Inc. J Comput Chem 26: 1069–1078, 2005
Role of the surface heterogeneity in adsorption of hydrogen ions on metal oxides: Theory and simulations
Authors: Zarzycki Piotr , Szabelski Paweł , Charmas Robert 
Published: May 2005

AbstractIn this article we study the effect of energetic heterogeneity of a crystalline surface on the adsorption of hydrogen ions (protons) from the liquid phase. In particular, we examine the influence of the shape of the adsorption energy distribution on the equilibrium isotherms of hydrogen ions. To that purpose, a few popular distribution functions, including rectangular, exponential, and asymmetric Gaussian are considered. Additionally, multimodal distribution functions, which may correspond to the adsorption on different crystal planes of the oxide, are also used. Lateral interactions between adsorbed charges are modeled using the potential function proposed by Borkovec et al., which accounts also for polarization of the liquid medium. The results presented here are obtained using both Monte Carlo (MC) simulations and theoretical calculations involving Mean Field Approximation (MFA). They indicate that increased energetic heterogeneity of the adsorbing surface may, in general, considerably change the behavior of the adsorption isotherms, regardless of the assumed distribution function. It is also shown that the predictions of the proposed theory are consistent with the data obtained from the MC simulations. © 2005 Wiley Periodicals, Inc. J Comput Chem 26: 1079–1088, 2005
Triangular embeddings of complete graphs (neighborly maps) with 12 and 13 vertices
Authors: Ellingham M. N. , Stephens Chris 
Published: May 2005

AbstractIn this paper, we describe the generation of all nonorientable triangular embeddings of the complete graphs K12 and K13. (The 59 nonisomorphic orientable triangular embeddings of K12 were found in 1996 by Altshuler, Bokowski, and Schuchert, and K13 has no orientable triangular embeddings.) There are 182,200 nonisomorphic nonorientable triangular embeddings for K12, and 243,088,286 for K13. Triangular embeddings of complete graphs are also known as neighborly maps and are a type of twofold triple system. We also use methods of Wilson to provide an upper bound on the number of simple twofold triple systems of order n, and thereby on the number of triangular embeddings of Kn. We mention an application of our results to flexibility of embedded graphs. © 2005 Wiley Periodicals, Inc. J Combin Designs
The spectrum of cyclic BSA(ν, 3, λ; α) with α = 2, 3
Authors: Zhang Jing , Chang Yanxun 
Published: May 2005

AbstractBalanced sampling plans excluding contiguous units (or BSEC) were first introduced by Hedayat, Rao, and Stufken in 1988. In this paper, we generalize the concept of a cyclic BSEC to a cyclic balanced sampling plan to avoid the selection of adjacent units (or CBSA for short) and use Langford and extended Langford sequences to construct a cyclic BSA(ν, 3, λ; α) with α = 2, 3. We finally establish the necessary and sufficient conditions for the existence of a cyclic BSA(ν, 3, λ; α) where α = 2, 3. © 2005 Wiley Periodicals, Inc. J Combin Designs.
A miniaturized nebulization catheter for improved gene delivery to the mouse lung
Authors: Köping‐Höggård Magnus , Issa Mohamed M. , Köhler Tamara , Tronde Ann , Vårum Kjell M. , Artursson Per 
Published: May 2005

AbstractBackgroundThe available methods for administration of gene delivery systems to the lungs of small animals via nebulization have several drawbacks. These include lack of control over the delivered dose and a negative impact on the stability of the formulation. This paper describes a new nebulization catheter device for the administration of plasmid‐based gene delivery systems (polyplexes) as aerosols to the mouse lung in vivo.MethodsThe physical stability of naked pDNA and polyplexes formulated with chitosan oligomers and PEI was examined following nebulization with the catheter device. We also examined the in vitro transfection efficiency of the polyplexes recovered after nebulization. Lung distribution and gene expression after administration of the selected gene delivery systems to the mouse lung were also investigated.ResultsIn contrast to previously described nebulization methods, the structural integrity of the unprotected naked pDNA was maintained following nebulization by the catheter device, which indicates relatively mild nebulization conditions. In addition, the nebulization procedure did not affect the physical stability of the formulated polyplexes. Small volumes of the pDNA aerosol (10–20 µl) were delivered in a highly controlled and reproducible manner. The aerosol droplet size varied with the molecular weight of the polycations. Aerosol delivery via this method resulted in improved lung distribution of pDNA polyplexes and a six‐fold increase in the efficiency of gene delivery in vivo over that seen with the commonly used intratracheal instillation method.ConclusionThe use of the nebulization catheter device provides a promising alternative for aerosol gene delivery to the mouse lung. Copyright © 2005 John Wiley & Sons, Ltd.
Diffusion tensor fractional anisotropy of the normal‐appearing seven segments of the corpus callosum in healthy adults and relapsing‐remitting multiple sclerosis patients
Authors: Hasan Khader M. , Gupta Rakesh K. , Santos Rafael M. , Wolinsky Jerry S. , Narayana Ponnada A. 
Published: May 2005

AbstractPurposeTo investigate the utility of whole‐brain diffusion tensor imaging (DTI) in elucidating the pathogenesis of multiple sclerosis (MS) using the normal‐appearing white matter (NAWM) of the corpus callosum (CC) as a marker of occult disease activity.Materials and MethodsA high signal‐to‐noise ratio (SNR) and optimized entire brain DTI data were acquired in 26 clinically‐definite relapsing and remitting multiple sclerosis (RRMS) patients and 32 age‐matched healthy adult controls. The fractional anisotropy (FA) values of seven functionally distinct regions in the normal‐appearing CC were compared between patients and controls.ResultsThis study indicates that 1) there was a gender‐independent FA heterogeneity of the functionally specialized CC segments in normal volunteers; 2) FA in the MS group was significantly decreased in the anterior (P = 0.0039) and posterior (P = 0.0018) midbody subdivisions of the CC, possibly due to a reduction of small‐caliber axons; and 3) the FA of the genu of the CC was relatively intact in the MS patients compared to the healthy age‐matched controls (P = 0.644), while the splenium showed an insignificant trend of reduced FA values (P = 0.248). The decrease in FA in any of the CC subdivisions did not correlate with disease duration (DD) or the expanded disability status scale (EDSS) score.ConclusionThe preliminary results are consistent with published histopathology and clinical studies on MS, but not with some published DTI reports. This study provides insights into the pathogenesis of MS, and the role played by compromised axonal integrity in this disease. J. Magn. Reson. Imaging 2005;21:735–743. © 2005 Wiley‐Liss, Inc.
Prognostic value of dynamic MR imaging for non‐small‐cell lung cancer patients after chemoradiotherapy
Authors: Ohno Yoshiharu , Nogami Munenobu , Higashino Takanori , Takenaka Daisuke , Matsumoto Sumiaki , Hatabu Hiroto , Sugimura Kazuro 
Published: May 2005

AbstractPurposeTo determine the prognostic value of dynamic MRI for non‐small‐cell lung cancer (NSCLC) patients after chemoradiotherapy.Materials and MethodsA total of 114 consecutive patients with NSCLC underwent dynamic MRI after chemoradiotherapy. The patients were divided into two groups (local control (n = 22) and local failure (n = 92)) according to the presence of local recurrence. From the signal intensity‐time course curve in each subject, the maximum relative enhancement ratio and slope of enhancement were calculated, and compared between two groups by Student's t‐test. To determine the feasible threshold values of both MR indexes for group differentiation, ROC‐based positive tests were performed. Finally, the Kaplan‐Meier survival curves of each group divided by the adapted threshold value were compared by log‐rank test.ResultsThe maximum relative enhancement ratio and the slope of enhancement in the local control group were significantly lower than those in the local failure group (P < 0.05). Using 0.08/sec as the threshold value of the slope of enhancement, the sensitivity and specificity for differentiation between the two groups were 90.9% and 91.3%, respectively. When the slope of enhancement was adopted for estimation of prognosis after therapy, the mean survival period of the slope of enhancement ≤ 0.08/sec group was significantly longer than that seen in the group with a slope of enhancement > 0.08/sec (P < 0.0001).ConclusionDynamic MRI has potential prognostic value for NSCLC patients after chemoradiotherapy. J. Magn. Reson. Imaging 2005;21:775–783. © 2005 Wiley‐Liss, Inc.
Diffusion‐weighted MRI of the lung with hyperpolarized helium‐3: A study of reproducibility
Authors: Morbach Andreas E. , Gast Klaus K. , Schmiedeskamp Jörg , Dahmen Anja , Herweling Annette , Heussel Claus P. , Kauczor Hans‐Ulrich , Schreiber Wolfgang G. 
Published: May 2005

AbstractPurposeTo determine the reproducibility of several parameters of the ADC measurement by calculating the scan‐to‐scan intrasubject variability.Materials and MethodsMeasurements were performed using a gradient‐echo sequence with a bipolar gradient for diffusion weighting (b = 3.89 sec/cm2). Five patients with pulmonary emphysema, and six healthy‐lung volunteers were included in the study. Images were acquired after inspiration of3He during a single inspiratory breath‐hold. To assess the reproducibility, the measurement was performed twice (time between measurements = 20 minutes) without repositioning the subjects. Analysis was performed on the basis of region‐of‐interest (ROI) analysis and global lung ADC histograms.ResultsThe mean ADC of a ROI varied by 5.1% between two measurements for volunteers and by 6.1% for patients. In the global evaluation, the 75th percentile demonstrated the best reproducibility (2%), while other parameters showed variations up to 12%. Only the variation of the standard deviation (SD) and the measure of homogeneity of the ADC map showed a significant difference between patients and volunteers.ConclusionDiffusion‐weighted imaging (DWI) is a well‐reproducible method for assessing the lung microstructure. J. Magn. Reson. Imaging 2005;21:765–774. © 2005 Wiley‐Liss, Inc.
High‐dose Gd‐DTPA vs. Bis‐Gd‐mesoporphyrin for monitoring laser‐induced tissue necrosis
Authors: Bremer Christoph , Bankert Joerg , Filler Timm , Ebert Wolfgang , Tombach Bernd , Reimer Peter 
Published: May 2005

AbstractPurposeTo compare Bis‐Gd‐mesoporphyrin (Bis‐Gd‐MP), a contrast agent with a reported high affinity to necrotic tissue, with high‐dose gadopentate dimeglumin (Gd‐DTPA) for defining laser‐induced muscle and liver necrosis by contrast‐enhanced (CE) MRI.Materials and MethodsLaser‐induced interstitial thermotherapy (LITT) was performed in the muscle and liver tissue of New Zealand White rabbits (1500 J and 2100 J; n = 80 lesions). The animals were randomly assigned to a group that received 0.3 mmol/kg bw Gd‐DTPA or a group that received 0.05 mmol/kg bw Bis‐Gd‐MP. Following contrast injection, dynamic MRI was performed on muscle lesions with a T1‐weighted, two‐dimensional, fast low‐angle shot (FLASH) sequence. The liver and muscle lesions were then repeatedly imaged for six hours after contrast injection using a T1‐weighted spin‐echo (SE) sequence. Central and peripheral lesion enhancement was determined and correlated with gross pathology and microscopy findings.ResultsBoth contrast agents allowed precise determination of lesion diameters with an average accuracy of 6.8% ± 1.3%. Rim enhancement during dynamic MRI was superior for Gd‐DTPA (P < 0.001) and revealed slightly higher lesion diameters compared to the results of follow‐up MR studies. A persistent enhancement of necrotic liver and muscle tissue was observed for both contrast agents throughout the observation period, suggesting that simple diffusion‐type processes may underlie the supposed affinity of Bis‐Gd‐MP for tissue necrosis.ConclusionBis‐Gd‐MP and Gd‐DTPA are equally well suited for postinterventional lesion assessment in LITT. J. Magn. Reson. Imaging 2005;21:801–808. © 2005 Wiley‐Liss, Inc.
Region‐growing segmentation of brain vessels: An atlas‐based automatic approach
Authors: Passat Nicolas , Ronse Christian , Baruthio Joseph , Armspach Jean‐Paul , Maillot Claude , Jahn Christine 
Published: May 2005

AbstractPurposeTo propose an atlas‐based method that uses both phase and magnitude images to integrate anatomical information in order to improve the segmentation of blood vessels in cerebral phase‐contrast magnetic resonance angiography (PC‐MRA).Material and MethodsAn atlas of the whole head was developed to store the anatomical information. The atlas divides a magnitude image into several vascular areas, each of which has specific vessel properties. It can be applied to any magnitude image of an entire or nearly entire head by deformable matching, which helps to segment blood vessels from the associated phase image. The segmentation method used afterwards consists of a topology‐preserving, region‐growing algorithm that uses adaptive threshold values depending on the current region of the atlas. This algorithm builds the arterial and venous trees by iteratively adding voxels that are selected according to their grayscale value and the variation of values in their neighborhood. The topology preservation is guaranteed because only simple points are selected during the growing process.ResultsThe method was performed on 40 PC‐MRA images of the brain. The results were validated using maximum‐intensity projection (MIP) and three‐dimensional surface rendering visualization, and compared with results obtained with two non‐atlas‐based methods.ConclusionThe results show that the proposed method significantly improves the segmentation of cerebral vascular structures from PC‐MRA. These experiments tend to prove that the use of vascular atlases is an effective way to optimize vessel segmentation of cerebral images. J. Magn. Reson. Imaging 2005;21:715–725. © 2005 Wiley‐Liss, Inc.
Feasibility of in vivo, multicontrast‐weighted MR imaging of carotid atherosclerosis for multicenter studies
Authors: Chu Baocheng , Zhao Xue‐Qiao , Saam Tobias , Yarnykh Vasily L. , Kerwin William S. , Flemming Kelly D. , Huston John , Insull William , Morrisett Joel D. , Rand Scott D. , DeMarco Kevin J. , Polissar Nayak L. , Balu Niranjan , Cai Jianming , Kampschulte Annette , Hatsukami Thomas S. , Yuan Chun 
Published: May 2005

AbstractPurposeTo test the image quality (ImQ) and interscan coverage of MRI for measuring carotid atherosclerosis across multiple centers.Materials and MethodsThirty‐nine subjects from five clinical sites (site 1: n = 11; site 2: n = 16; site 3: n = 2; site 4: n = 3; site 5: n = 7) were imaged on GE 1.5T scanners using a standardized carotid imaging protocol with five weightings (T1, proton density (PD), T2, time‐of‐flight (TOF), and contrast‐enhanced (CE) T1). MR technologists from the five sites received comprehensive protocol training. A maximum coverage of 24 mm (12 slices) was designed for each of four scans (baseline and at four, eight, and 13 weeks). The adequacy of coverage was calculated as the percentage of arteries with at least six slices matched across all four scans. ImQ was evaluated using an established five‐point scale for each image. ImQ ≥ 3 was considered acceptable for image analysis.ResultsAcross five sites, the mean ImQ was 3.4–4.2 for T1W, 3.6–4.4 for CE‐T1W, 3.4–4.2 for PDW, 3.3–4.2 for T2W, and 3.4–4.0 for TOF. The mean ImQ per site was 3.5–4.2. All sites generated at least six‐slice coverage (mean = 8.0–9.1) for all index carotid arteries.ConclusionThe ImQ and coverage values were comparable among clinical sites using a standardized carotid imaging protocol. With comprehensive protocol training, carotid MRI is technically feasible for use in multicenter studies. J. Magn. Reson. Imaging 2005;21:809–817. © 2005 Wiley‐Liss, Inc.
Breast MRI findings after modified radical mastectomy and transverse rectus abdominis myocutaneous flap in patients with breast cancer
Authors: Kang Bong Joo , Jung Jung Im , Park Changsook , Park Woo Chan , Jeon Hae Myung , Hahn Seong Tai , Lee Jae Mun 
Published: May 2005

AbstractPurposeTo evaluate the MRI findings in breast cancer patients who had undergone a modified radical mastectomy (MRM) and a transverse rectus abdominis myocutaneous (TRAM) flap.Materials and MethodsMRI was performed on 20 patients who had been diagnosed with breast cancer and had undergone an MRM and TRAM flap. The results were examined in terms of MRI's ability to detect the flap and assess possible postoperative changes and recurrence. In addition, MRI images of the opposite breast were analyzed. Follow‐up examinations were carried out on 11 patients, and all changes were assessed.ResultsThe flap was clearly visualized by MRI in all of the patients. The signal intensity of the flap was equivalent to that of fat. The contact zone between the TRAM flap and the mastectomy site was enhanced after contrast infusion. Postoperative changes, such as skin thickening (n = 20), edema (n = 2), fluid collection (n = 3), hematoma (n = 1), and fat necrosis (n = 3), were detected. In two patients, artificially inserted fat tissue was identified. On the MRI of the opposite breast, enhancing lesions were detected in seven patients. In one patient with this finding, ductal carcinoma in situ was diagnosed. On the follow‐up MRI, a decrease in skin thickening, fat necrosis, and hematoma was detected.ConclusionMRI is an effective method for lesion detection and evaluation of postoperative changes after MRM and TRAM flap, as well as for evaluation of the opposite breast. J. Magn. Reson. Imaging 2005;21:784–791. © 2005 Wiley‐Liss, Inc.
Anthropometric data for magnetic resonance imaging of the carotid bifurcation
Authors: Thomas Jonathan B. , Jong Lisa , Spence J. David , Wasserman Bruce A. , Rutt Brian K. , Steinman David A. 
Published: May 2005

AbstractPurposeTo provide anthropometric data applicable to the design of protocols for high‐resolution magnetic resonance imaging (MRI) of the carotid bifurcation, particularly those aimed at elucidating the role of local factors in carotid atherogenesis.Materials and MethodsAxial black‐blood MR images of the carotid bifurcation were acquired from 25 young, healthy volunteers and 25 older, asymptomatic patients, from which were measured a variety of quantities related to the orientation and placement of the bifurcation within the neck.ResultsDescriptive statistics were obtained for the following quantities: separation of the bifurcation apices within (57.8 ± 6.7 mm) and between (4.9 ± 4.1 mm) axial slices; orientation of the bifurcation within the axial plane (31.7 ± 26.9°), and of the common carotid artery (CCA) relative to the sagittal (7.5 ± 7.1°) and coronal (7.9 ± 7.8°) planes; depth of the bifurcation from the skin surface (29.5 ± 7.2 mm); and neck width (125.9 ± 14.4 mm).ConclusionIn most cases, both carotid arteries may be captured, without aliasing, within a 12‐cm field‐of‐view axial image; however, the two apices will rarely be captured within the same axial slice. The CCA is significantly oblique to the body axis, but at angles sufficiently acute to permit the use of axial slices. Finally, a significant linear relationship between neck width and carotid depth may be used to inform radio frequency (RF) coil selection prior to scanning a subject, and hence facilitate optimal imaging in light of the wide anatomic variations observed. J. Magn. Reson. Imaging 2005;21:845–849. © 2005 Wiley‐Liss, Inc.