bluuebunny/crossref_metadata_2025_split huggingface dataset:
Hyaluronan Increases RANKL Expression in Bone Marrow Stromal Cells Through CD44
Authors: Cao Jay J , Singleton Patrick A , Majumdar Sharmila , Boudignon Benjamin , Burghardt Andrew , Kurimoto Pam , Wronski Thomas J , Bourguignon Lilly YW , Halloran Bernard P 
Published: October 2007

Abstract
HA activates CD44 to stimulate RANKL expression in bone marrow stromal cells. HA stimulation of RANKL is blocked by anti-CD44 antibody and is absent in cells from CD44−/− mice. CD44−/− mice exhibit thicker cortical bone and a smaller medullary cavity, but indices of bone resorption are not affected.
Introduction: Hyaluronan (HA), the major nonprotein glycosaminoglycan component of the extracellular matrix in mammalian bone marrow, functions in part through its receptor, CD44, to stimulate a series of intracellular signaling events that lead to cell migration, adhesion, and activation. To determine whether HA activation of CD44 influences RANKL and osteoprotegerin (OPG) expression and whether CD44 is functionally important in bone metabolism, we studied whole bone and bone marrow stromal cells (BMSCs) from wildtype and CD44−/− mice.
Materials and Methods: BMSCs from wildtype and CD44−/− mice at 7 weeks of age were cultured and treated with either HA or anti-CD44 antibody. The levels of mRNA of RANKL, OPG, CD44, alkaline phosphatase (ALP), osteocalcin (OC), and αI collagen (COLL) were determined by quantitative real-time RT-PCR. Levels of RANKL and CD44 protein were measured by immunoblotting, and expression of CD44 in whole bone was determined by immunohistochemical staining. Double immunofluorescence staining and confocal microscopy were used to study colocalization of Cbfa1, CD44, and HA. Tibias were imaged using μCT, and cancellous and cortical parameters were measured. Osteoblast and osteoclast surface in the distal femoral metaphysis and osteoclast on the endocortical surface at the tibio-fibular junction were measured using quantitative histomorphometry. Differences were analyzed using ANOVA and the Newman-Keuls test.
Results: Addition of HA dose-dependently increased RANKL mRNA (3.6-fold) and protein (3-fold) levels in BMSCs. Stimulation of RANKL by HA could be blocked with anti-CD44 antibody. Treatment of cells with HA or anti-CD44 antibody had no significant effect on OPG mRNA levels. Both CD44 and HA localized on the plasma membrane in cells expressing Cbfa1. HA localization on the cell membrane disappeared when cells were preincubated with anti-CD44 antibody. Compared with control mice, cortical bone of CD44−/− was thicker, and medullary area was smaller at both 7 and 17 weeks, but at 7 weeks, indices of bone resorption were normal. At 17 weeks of age, tibial mass of CD44−/− mice was higher than control mice. CD44−/− animals expressed less RANKL in whole bone (−30%) and in BMSCs (−50%). Cells from CD44−/− animals failed to respond to either HA or CD44 antibody treatment.
Conclusions: HA can increase RANKL expression in BMSCs through CD44.
Mice Lacking the Integrin β5 Subunit Have Accelerated Osteoclast Maturation and Increased Activity in the Estrogen-Deficient State
Authors: Lane Nancy E , Yao Wei , Nakamura Mary C , Humphrey Mary Beth , Kimmel Donald , Huang Xiaozhu , Sheppard Dean , Ross F Patrick , Teitelbaum Steven L 
Published: October 2007

Abstract
Integrin αvβ5 is expressed on osteoclast precursors and is capable of recognizing the same amino acid motif as αvβ3. Three-month-old β5−/− female OVX mice had increased osteoclastogenesis ex vivo, and μCT assessment of trabecular bone volume was 53% lower than WT-OVX animals. These preliminary data suggest αvβ5 integrin's presence on osteoclast precursors may inhibit of osteoclast formation.
Introduction: Osteoclasts are unique resorptive skeletal cells, capable of degrading bone on contact to the juxtaposed matrix. Integrin αvβ5 is expressed on osteoclast precursors, structurally similar to αvβ3, and capable of recognizing the same amino acid motif. Given the structural relationship and reciprocal regulation of αvβ3 and αvβ5, the purpose of this study was to evaluate how αvβ5 might contribute to osteoclast maturation and activity.
Materials and Methods: Three-month-old wildtype (WT) and β5−/− female mice had ovariectomy (OVX) or sham operations. The osteoclastogenic capacity of marrow-derived precursors, the kinetic, the circulating, and structural parameters of bone remodeling, was determined after 6 weeks of paired feeding.
Results and Conclusions: OVX increased osteoclastogenesis ex vivo and in vivo. Osteoclast formation and prolonged pre-osteoclast survival were substantially enhanced in cultures containing β5−/− cells whether obtained from sham-operated or OVX mice. Expression of cathepsin K, β3 integrin subunit, and calcitonin receptor were accelerated in cultured β5−/−osteoclasts. β5−/− osteoclasts from OVX animals showed a 3-fold enhancement of net resorptive activity, with quantitative μCT showing trabecular bone volume loss after OVX 53% greater in β5−/− OVX compared with similarly treated WT OVX mice (p &lt; 0.05). α5β3 seems to be an inhibitor of osteoclast formation, in contrast to αvβ3. In addition, loss of αvβ5 seems to accelerate osteoclast formation in the OVX model. Further examination of αvβ5 signaling pathways may enhance our understanding of the activation of bone resorption.
RANKL Regulates Fas Expression and Fas-Mediated Apoptosis in Osteoclasts
Authors: Wu Xiaojun , Pan George , McKenna Margaret A , Zayzafoon Majd , Xiong Wen-Cheng , McDonald Jay M 
Published: October 2007

Abstract
Osteoclast apoptosis is an influential determinant of osteoclast bone-resorbing activity. RANKL, a critical factor for osteoclastogenesis, is also important in osteoclast survival. However, the mechanisms by which RANKL prevents osteoclast apoptosis remain largely unknown.
Introduction: Fas, a death receptor, mediates apoptosis in multiple types of cells including osteoclasts. Here we report that RANKL acts as a survival factor in osteoclasts by downregulating Fas-mediated apoptosis and Fas expression in mature osteoclasts.
Materials and Methods: RAW264.7 and mouse bone marrow macrophage/monocyte progenitors and progenitor-derived osteoclasts, in the presence of various concentrations of RANKL, were used in this study. Western blotting, semiquantitative RT-PCR, flow cytometry, nuclear staining, and a fluorescent caspase-3 activity assay were used to assess the effect of RANKL on Fas expression and Fas-mediated apoptosis. The involvement of NF-κB in the regulation of Fas by RANKL was analyzed by luciferase assay and EMSA.
Results: Mature osteoclasts generated in the presence of a high concentration of RANKL (3.33 nM) failed to respond to Fas-induced apoptosis. The lack of responsiveness in mature osteoclasts is caused by the low level of Fas expression, as detected by both semiquantitative PCR and Western blotting. Fas protein and mRNA expression are inhibited by RANKL in concentration-dependent manners. The downregulation of Fas expression by RANKL is not because of modulation of the stability of Fas protein or mRNA. The regulation of Fas expression by RANKL is biphasic. During the early stage of osteoclastogenesis (1 day) when Fas is expressed at a very low level, RANKL upregulates Fas promoter activity by 2.4 ± 0.1-fold in a concentration-dependent manner and increases Fas mRNA and protein. This event correlates with regulation of the binding activity of NF-κB to the Fas promoter by RANKL, as detected by EMSA. In osteoclast precursors, the induction of Fas promoter activity by RANKL was dramatically reduced when NF-κB binding sites on the Fas promoter were mutated.
Conclusion: RANKL upregulates Fas expression in osteoclast progenitors through NF-κB, making osteoclasts targets of Fas-stimulated apoptosis. In differentiated mature osteoclasts, RANKL reduces the levels of Fas expression and Fas-mediated apoptosis, acting as a survival factor.
Abdominal Aortic Calcification Detected on Lateral Spine Images From a Bone Densitometer Predicts Incident Myocardial Infarction or Stroke in Older Women
Authors: Schousboe John T , Taylor Brent C , Kiel Douglas P , Ensrud Kristine E , Wilson Kevin E , McCloskey Eugene V 
Published: October 2007

Abstract
Among a cohort of elderly women, abdominal aortic calcification scored on baseline lateral spine densitometric images intended for vertebral fracture assessment was associated with subsequent myocardial infarction or stroke over a median 4-yr period, independent of clinical cardiovascular disease risk factors.
Introduction: Cardiovascular disease (CVD) risk among older women is not adequately captured by traditional CVD risk factors. Lateral spine images obtained on bone densitometers for vertebral fracture assessment (VFA) can detect abdominal aortic calcification (AAC), an important marker of subclinical CVD. Our objective was to estimate the association between AAC scored on VFA images and subsequent myocardial infarction (MI) or stroke in elderly women.
Materials and Methods: Among participants in a randomized controlled trial (women; age &gt;75 yr) of clodronate versus placebo, those who sustained an MI or stroke during the median 4-yr follow-up study period were selected as cases (n = 408), and 408 controls were randomly selected from the remainder of the parent study population. Baseline VFA images were scored for AAC with a previously validated 24-point scale and a newer, simpler 8-point scale.
Results: The OR of incident MI or stroke for those in the middle and top tertiles, respectively, compared with the bottom tertile of AAC score were 1.14 (95% CI, 0.79–1.66) and 1.74 (95% CI, 1.19–2.56) for the 24-point scale and 1.42 (95% CI, 0.98–2.05) and 1.77 (95% CI, 1.22–2.55) for the 8-point scale, adjusted for age, high-density lipoprotein and low-density lipoprotein cholesterol, triglycerides, blood pressure, smoking, renal function, health status, and baseline diagnoses of diabetes mellitus, hypertension, angina, and prior stroke.
Conclusions: AAC scored on VFA images is independently associated with incident MI or stroke. Because bone densitometry is indicated for all women ≥65 yr of age, VFA imaging offers an opportunity to capture this CVD risk factor in postmenopausal women undergoing bone densitometry at very little additional cost.
Effect of Specimen Size on Quasi-Elastic Properties of Toyoura Sand in Hollow Cylinder Triaxial and Torsional Shear Tests
Authors: HongNam Nguyen , Koseki Junichi , Sato Takeshi 
Published: October 2007

Abstract
Quasi-elastic deformation properties of dry, dense Toyoura sand were experimentally investigated by triaxial and torsional shear tests on hollow cylindrical specimens of medium sizes (outer diameter Do=20 cm, inner diameter Di=16 or, 12 cm, and height H=30 cm) and small size (Do=10, Di=6, H=20 cm). In addition to the conventional external measurements, strains were measured locally by the newly developed pin-type local deformation transducers. The effect of specimen size on locally measured Young’s modulus Ez was insignificant. On the other hand, the locally measured values of shear modulus Gzθ with the small size specimen revealed lower reproducibility as compared with those measured with the medium size specimens, suggesting that larger specimen size is preferred in evaluating the small strain shear modulus in torsional shear tests on hollow cylindrical specimens. It was also inferred from the test results that, irrespective of the specimen size, effect of end restraint at the top cap and pedestal is significant on the externally measured values of Gzθ.
Quality Assurance Program for Soldering Copper Roofs
Authors: Michener Mark L. , Hoernschemeyer Craig A. 
Published: October 2007

Abstract
Since the early 1700s, the art of coppersmithing has been used to construct watertight roofing systems. For low slope, flat seam roofing systems, soldered locked seams and riveted lap joints are essential for the success of this type of system. However, industry standards for testing and monitoring quality assurance to produce a watertight metal roofing product are vague and are not adequately equated to contractor performance. This paper will trace the development of a soldering quality assurance program developed for historical roofing restoration projects requiring watertight seams.
The replacement of the original copper roofing on Kingswood School, Cranbrook Educational Community, a National Historic Landmark in Michigan, serves as a model for this current research. Designed by noted architect Eliel Saarinen and constructed in 1931, the building’s extensive copper roof is a character-defining feature of the Prairie Style structure. Because of the importance of the architectural feature, a quality assurance program during reconstruction was necessary to develop a confidence level that performance of the copper roofing would meet or exceed expectations.
Procedures were developed for certifying coppersmiths for flat locked and riveted seams. Standardized field observations and reports were created to provide continuous documentation of the contractor’s work. Variables examined in the work included joint geometry and soldering necessary for the production of watertight seams. Field observations include solder consumption rates to ensure adequate penetration of the seam.
This quality assurance program is designed to identify crucial aspects of a copper roofing system in order to effectively evaluate compliance with design requirements. The program recognizes the need for traditional artistry while incorporating new technology to improve roofing performance. The methodology presented in this paper can be directly employed to develop standards for monitoring copper roof system construction.
Development of the Strasshof Tief Sour-Gas Field Including Acid-Gas Injection Into Adjacent Producing Sour-Gas Reservoirs
Authors: Behrend Jens , Chugh Shelin , McKishnie Robert A. 
Published: October 2007

Summary
OMV operates two producing sour-gas reservoirs in lower Austria: the Reyersdorfer dolomite (shallow reservoir) and the Schoenkirchen Uebertief dolomite (deep reservoir). A new, separate reservoir called the Perchtoldsdorfer dolomite (Strasshof Tief field) has been discovered, and options for how its acid gas can be handled are being investigated. The two currently producing reservoirs deliver to a gas plant with a 30-tonne/d sulfur plant. The sulfur plant is too small to accommodate the additional production. OMV has evaluated acid-gas injection as an alternative to a new, larger sulfur plant. Acid gas could be injected into either the Reyersdorfer dolomite or the Schoenkirchen Uebertief dolomite. In either case, injection would be occurring concurrently with production. Three injection scenarios are contemplated: 200, 400, and 800×103 std m3/d (6.4, 12.8, and 25.6 MMcf/D). The applied acid-gas composition is carbon dioxide (CO2) (80%), hydrogen sulfide (H2S) (16%), nitrogen (N2) (3%), and methane (CH4 or C1) (1%).
The intent of this project was to determine at a scoping level if sufficient injectivity and storativity are available in either the Reyersdorfer dolomite or the Schoenkirchen Uebertief dolomite. Compositional modeling and the prognosis of the breakthrough time at the producing wells were carried out to determine the contamination risk to existing production.
The simulation work included generating compositional numerical-simulation forecasts of production-rate/composition forecasts under concurrent injection/production scenarios; modeling in-situ miscibility and gravity-separation effects of acid gas; and evaluating risk scenarios for existing production to determine the optimal solution.
Core-Data Preprocessing To Improve Permeability-Log Estimation
Authors: Cozzi Mauro , Ruvo Livio , Scaglioni Paolo , Lyne Anna Maria 
Published: October 2007

Summary
Two techniques of preprocessing data from core plugs have been investigated to enhance the quality of synthetic permeability estimation from conventional logs by use of artificial neural networks (ANNs). A first technique consists of "cleaning" the core-plug data set by removing the measurements deemed log-incompatible (i.e., those from plugs corresponding to log measurements affected by shoulder-bed effect or layers with thickness below the vertical log resolution). The second technique relies on building high-resolution digital models of cored intervals by use of a process-oriented-modeling (POM) approach—the core model is populated with permeability values from core plugs and then upscaled to a log-equivalent support volume.
Synthetic permeability curves estimated with these techniques have been compared to synthetic permeability curves estimated without core-data preprocessing and to permeability estimated directly from core plugs and properly calibrated permeability curves from a nuclear magnetic resonance (NMR) log tool in a turbidite reservoir, the ground truth value being represented by actual dynamic data. Results highlight that core-to-log scale effects play a major role in the permeability estimation from conventional logs and show that the proposed preprocessing techniques can be effective in improving permeability prediction, because they significantly reduce cross-scaling problems related to the differences in support volumes.
Strengths and weaknesses of the two preprocessing approaches also have been compared. The first technique is faster, but its application is strongly constrained by the statistical and geological representativeness of the selected data set. This is because some lithologies go underrepresented so as to question the use of estimation tools like ANNs. Conversely, the POM preprocessing technique is more time-consuming and needs detailed core descriptions, but has the great advantage of supplying—starting from core data only—a reliable permeability curve that retains its validity at the log scale.
Waterflooding Surveillance and Monitoring: Putting Principles Into Practice
Authors: Terrado Martin , Yudono Suryo , Thakur Ganesh 
Published: October 2007

Summary
This paper illustrates how practical application of surveillance and monitoring principles is a key to understanding reservoir performance and identifying opportunities that will improve ultimate oil recovery. Implementation of various principles recommended by industry experts is presented using examples from fields currently in production.
Practices in processing valuable information and analyzing data from different perspectives are presented in a methodical way on the following bases: field, block, pattern, and wells. A novel diagnostic plot is presented to assess well performance and identify problem wells for the field.
Results from the application of these practices in a pilot area are shared, indicating that the nominal decline rate improved from 33 to 18% per year without any infill drilling. The change in the decline rate is attributed primarily to effective waterflood management with a methodical approach, employing an integrated multifunctional team.
Although the suggested techniques can be applied to any oil field undergoing a waterflood, they are of great value to mature waterfloods that involve significant production history. In these cases, prioritization is a key aspect to maintain focus on the opportunities that will add the most value during the final period of the depletion cycle. Case studies illustrating the best surveillance practices are discussed.
Optimal Waterflood Management Using Rate Control
Authors: Alhuthali Ahmed H. , Oyerinde Adedayo , Datta-Gupta Akhil 
Published: October 2007

Summary
Field-scale rate optimization problems often involve highly complex reservoir models, production-and-facilities related constraints, and a large number of unknowns. These factors make optimal reservoir management through rate- and flood-front control difficult without efficient optimization tools. Some aspects of the optimization problem have been studied before mainly using an optimal control theory. However, the applications to date have been rather limited to small problems because of the computation time and the complexities associated with the formulation and solution of adjoint equations. Field-scale rate optimization for maximizing waterflood sweep efficiency under realistic field conditions has remained largely unexplored.
This paper proposes a practical and efficient approach for computing optimal injection and production rates, thereby managing the waterflood front to maximize sweep efficiency and delaying the arrival time to minimize water cycling. Our work relies on equalizing the arrival times of the waterflood front at all producers within selected subregions of a waterflood project. The arrival-time optimization has favorable quasilinear properties, and the optimization proceeds smoothly, even if our initial conditions are far from the solution. Furthermore, the sensitivity of the arrival time with respect to injection and production rates can be calculated analytically using a single-flow simulation. This makes our approach computationally efficient and suitable for large-scale field applications. The arrival time optimization ensures appropriate rate allocation and flood-front management by delaying the water breakthrough at the producing wells.
Several examples are presented to support the robustness and efficiency of the proposed optimization scheme. These include several 2D-synthetic examples for validation purposes and a 3D field application. In addition, we demonstrate the potential of the approach to optimize the flow profile along injection/production segments of horizontal-smart wells.
Important Modeling Parameters for Predicting Steamflood Performance
Authors: Satik Cengiz , Kumar Mridul , DeFrancisco Sam , Hoang Viet , Basham Mike 
Published: October 2007

Summary
A comprehensive numerical modeling study was performed to investigate impact of pattern confinement on steamflood simulation results, using a three-phase and 3D thermal reservoir simulator. In addition, the effects of cyclic steaming of the producers, grid size, and other physical parameters were evaluated. Detailed multipattern, single-sand steamflood models were constructed using properties of a heavy-oil field in California. All models included an initial primary depletion zone of 6 ft within 60 ft of net pay. Up to twenty-five, 2.5-acre patterns were included in the study.
Results show that finely gridded models accurately capture near-vertical steam override and oil drainage by gravity with a near-horizontal steam/oil interface. High injection pressures observed in many prior simulations are primarily a result of confined reservoir models. Steam-zone pressures and temperatures are similar to those typically observed in the field, when the model is unconfined (i.e., the model area is greater than the pattern area), representing undeveloped portions of the field. Moreover, including cyclic steaming of producers accelerates the steam breakthrough time and lowers injection pressures. During the postbreakthrough steam-rate-reduction period, field-observed oil-production response is represented better when the influence of surrounding patterns is included. Production-rate decline is relatively small when injection rate is reduced only in the primary pattern(s); however, the decline rate increases if rate reduction is implemented in the entire field.