bluuebunny/crossref_metadata_2025_split huggingface dataset:
Hereditary ovarian cancer in Poland
Authors: Menkiszak Janusz , Gronwald Jacek , Górski Bohdan , Jakubowska Anna , Huzarski Tomasz , Byrski Tomasz , Foszczyńska‐Kłoda Małgorzata , Haus Olga , Janiszewska Hanna , Perkowska Magdalena , Brożek Izabela , Grzybowska Ewa , Zientek Helena , Góźdź Stanisław , Kozak‐Klonowska Beata , Urbański Krzysztof , Miturski Roman , Kowalczyk Jerzy , Plużańska Anna , Niepsuj Stanisław , Koc Jan , Szwiec Marek , Drosik Kazimierz , Mackiewicz Andrzej , Lamperska Katarzyna , Stróżyk Elwira , Godlewski Dariusz , Stawicka Małgorzata , Waśko Bernard , Bebenek Marek , Rozmiarek Andrzej , Rzepka‐Górska Izabella , Narod Steven A. , Lubiński Jan 
Published: August 2003

AbstractThere is increasing evidence that hereditary factors play a greater role in ovarian cancer than in any of the other common cancers of adulthood. This is attributable, to a large extent, to a high frequency of mutations in the BRCA1 or BRCA2 genes. In Poland, 3 common founder mutations in BRCA1 account for the majority of families with identified BRCA mutations. Our study was conducted in order to estimate the prevalence of any of 3 founder BRCA1 mutations (5382insC, C61G and 4153delA) in 364 unselected women with ovarian cancer, and among 177 women with ovarian cancer and a family history of breast or ovarian cancer. A mutation was identified in 49 out of 364 unselected women with ovarian cancer (13.5%) and in 58 of 177 women with familial ovarian cancer (32.8%). The majority of women with ovarian cancer and a BRCA1 mutation have no family history of breast or ovarian cancer. The high frequency of BRCA1 mutations in Polish women with ovarian cancer supports the recommendation that all Polish women with ovarian cancer should be offered testing for genetic susceptibility, and that counseling services be made available to them and to their relatives. It is important that mutation surveys be conducted in other countries prior to the introduction of national genetic screening programs. © 2003 Wiley‐Liss, Inc.
Quasi‐rational and ex ante price expectations in commodity supply models: an empirical analysis of the US broiler market
Authors: Holt Matthew T. , McKenzie Andrew M. 
Published: August 2003

AbstractA statistically optimal inference about agents' ex ante price expectations within the US broiler market is derived using futures prices of related commodities along with a quasi‐rational forecasting regression equation. The modelling approach, which builds on a Hamilton‐type framework, includes endogenous production and allows expected cash price to be decomposed into anticipated and unanticipated components. We therefore infer the relative importance of various informational sources in expectation formation. Results show that, in addition to the quasi‐rational forecast, the true supply shock, future prices, and ex post commodity price forecast errors have, at times, been influential in broiler producers' price expectations. Copyright © 2003 John Wiley & Sons, Ltd.
A new coincident index of business cycles based on monthly and quarterly series
Authors: Mariano Roberto S. , Murasawa Yasutomo 
Published: August 2003

AbstractPopular monthly coincident indices of business cycles, e.g. the composite index and the Stock–Watson coincident index, have two shortcomings. First, they ignore information contained in quarterly indicators such as real GDP. Second, they lack economic interpretation; hence the heights of peaks and the depths of troughs depend on the choice of an index. This paper extends the Stock–Watson coincident index by applying maximum likelihood factor analysis to a mixed‐frequency series of quarterly real GDP and monthly coincident business cycle indicators. The resulting index is related to latent monthly real GDP. Copyright © 2002 John Wiley & Sons, Ltd.
Inferring the private information content of trades: a regime‐switching approach
Authors: Nyholm Ken 
Published: August 2003

AbstractThis paper presents an empirical model for inferring the private information content of trades at the transaction level. The trade‐indicator model of Glosten and Harris (1988) is extended to a two‐state regime‐switching setting, and the model is estimated using tick‐by‐tick data from the New York Stock Exchange (NYSE). The specialist is found to react in accordance with the proposed model. Bid–ask quotes set after the execution of a trade reflect the conjectured information content of that particular trade. Based on the estimated model four empirical results emerge: (a) the suggested regime‐switching model fit data well; (b) the reverse J‐shaped pattern of intra‐daily quoted spreads is shown to agree with the clustering of costs incurred by the specialist through trading with better‐informed agents; (c) on average 9% of all trades are found to reveal private: information to the specialist; (d) results regarding the trading volume of informed traders support the stealth trading hypothesis suggested by Barclay and Warner (1993). Copyright © 2003 John Wiley & Sons, Ltd.
Combinatorial characterization of cell interactions with polymer surfaces
Authors: Meredith J. Carson , Sormana Joe‐L. , Keselowsky Benjamin G. , García Andrés J. , Tona Alessandro , Karim Alamgir , Amis Eric J. 
Published: August 2003

AbstractWe report a novel combinatorial methodology for characterizing the effects of polymer surface features on cell function. Libraries containing hundreds to thousands of distinct chemistries, microstructures, and roughnesses are prepared using composition spread and temperature gradient techniques. The method enables orders of magnitude increases in discovery rate, decreases variance, and allows for the first time high‐throughput assays of cell response to physical and chemical surface features. The technique overcomes complex variable spaces that limit development of biomaterial surfaces for control of cell function. This report demonstrates these advantages by investigating the sensitivity of osteoblasts to the chemistry, microstructure, and roughness of poly(D,L‐lactide) and poly(ϵ‐caprolactone) blends. In particular, we use the phenomenon of heat‐induced phase separation in these polymer mixtures to generate libraries with diverse surface features, followed by culture of UMR‐106 and MC3T3‐E1 osteoblasts on the libraries. Surface features produced at a specific composition and process temperature range were discovered to enhance dramatically alkaline phosphatase expression in both cell lines, not previously observed for osteoblasts on polymer blends. © 2003 Wiley Periodicals, Inc. J Biomed Mater Res 66A: 483–490, 2003
Fracture toughness of human dentin
Authors: Iwamoto Nanako , Ruse N. Dorin 
Published: August 2003

AbstractThe purpose of this study was to determine the fracture toughness (KIC) of human dentin and to test the null hypothesis that KIC is not affected by the orientation of dentinal tubules relative to the plane of crack propagation. Triangular prisms (4 × 4 × 4 × 8 mm) were obtained from human molars and tested using the notchless triangular prism (NTP) specimen KIC test. Dentin prisms were prepared so that the plane of crack propagation would have three different orientations relative to the orientation of dentinal tubules: perpendicular (PE), parallel aligned (PAA), and parallel transverse (PAT). The prepared specimens were secured in the specimen holder and loaded in tension until fracture or crack arrest. The maximum load recorded was used to calculate KIC. There was no significant difference between the KIC of PAA specimens (1.97 ± 0.17 MPa/m1/2) and PAT (2.02 ± 0.18 MPa/m1/2). The KIC for the PE specimens (1.13 ± 0.36 MPa/m1/2) was significantly lower. The SEM images of the fractured surfaces showed distinct differences that were correlated with the determined KIC values. The fractured surfaces of PAA and PAT specimens were rougher compared to PE specimens. Both the hyper mineralized peritubular dentin and the orientation of collagen fibrils surrounding the tubules could be responsible for the significant differences in KIC. The results of this study identified a significant anisotropy of dentin with respect to its KIC. © 2003 Wiley Periodicals, Inc. J Biomed Mater Res 66A: 507–512, 2003
Chondrocytes seeded onto poly (L/DL‐lactide) 80%/20% porous scaffolds: A biochemical evaluation
Authors: Grad Sibylle , Zhou Lin , Gogolewski Sylwester , Alini Mauro 
Published: August 2003

AbstractRepair of articular cartilage remains a clinical and scientific challenge. The use of implantable chondrocyte‐seeded constructs offers a promising treatment option. The present study is focused on the culture of chondrocytes onto 3‐D poly (L‐/DL‐lactide) 80%/20% porous scaffolds. Scaffolds were seeded with bovine articular chondrocytes and cultured for up to 42 days. After an initial decrease, although not significant, the DNA content of the constructs remained constant over the culture time. A progressive increase in glycosaminoglycans and collagen was observed in the constructs during the culture period. However, a significant release of matrix molecules into the culture medium also was noticeable. On the transcriptional level, aggrecan mRNA expression was highest on day 14 and gradually decreased thereafter. Procollagen I mRNA expression constantly increased whereas procollagen II mRNA expression decreased after day 14, indicating that cells were dedifferentiating. Histologic analysis of the constructs demonstrated the deposition of a proteoglycan‐rich extracellular matrix by day 42 of culture. The present data demonstrate that poly (L‐/DL‐lactide) 80%/20% porous scaffolds support the development of a cartilage‐like extracellular matrix. The limitations of the system are the diffusion of large amounts of matrix molecules into the culture medium and the dedifferentiation of the chondrocytes with prolonged time in culture. © 2003 Wiley Periodicals, Inc. J Biomed Mater Res 66A: 571–579, 2003
Mineralization of matrix vesicles isolated from a human osteosarcoma cell line in culture with water‐soluble chitosan‐containing medium
Authors: Yamada Shizuka , Ohara Naoko , Hayashi Yoshihiko 
Published: August 2003

AbstractChitosan is a natural bioactive material. Although it has been reported that chitosan promotes osteogenesis in bone lesions, little is known about how chitosan modulates this process. The present study was designed to investigate the effect of water‐soluble chitosan relative to initiation of biologic mineralization, especially in the matrix‐vesicles‐(MVs) mediated processin vitro. A human osteoblastic cell line (NOS‐1) was used. After 3 days of incubation, the number of cells and alkaline phosphatase (ALP) activity increased significantly in the chitosan group. RT‐PCR analysis revealed that chitosan induced an increase in the expression of bone morphogenetic protein‐2 mRNA after 7 days of incubation. MVs were isolated from NOS‐1 cells using a collagenase digestion and ultracentrifugation method. ALP activity of MVs isolated from chitosan‐supplemented cells was significantly higher than that of the control group. Furthermore, isolated MVs were incubated in medium supplemented with Na‐β‐glycerophosphate without fetal bovine serum. Needle‐like crystals were observed in association with MVs after 24 h of incubation. These needle‐like crystals were densely accumulated in the chitosan group. The present findings suggest that water‐soluble chitosan would promote osteoblast proliferation and differentiation and may be useful for the acceleration of initial biologic mineralization. © 2003 Wiley Periodicals, Inc. J Biomed Mater Res 66A: 500–506, 2003
Expression of nitric oxide, peroxynitrite, and apoptosis in loose total hip replacements
Authors: Puskas Brian L. , Menke Nora E. , Huie Phil , Song Yong , Ecklund Kier , Trindade Michael C. D. , Smith R. Lane , Goodman Stuart B. 
Published: August 2003

AbstractNitric oxide (NO) is an effector molecule associated with inflammation, immune function, bone metabolism, and the induction of apoptosis. This study examined the role of NO, peroxynitrite (ONOO−), and apoptosis in cases of revision total hip replacements (THRs). We hypothesized that apoptosis and excess production of NO contribute to the inflammatory reaction to orthopedic biomaterial wear debris that is associated with loosening and osteolysis. Periprosthetic membranous specimens were collected from revised cemented acetabular components with simple loosening and ballooning osteolysis. Synovial samples from patients undergoing primary THR were used as controls. The presence of macrophages (CD68+) and levels of inducible nitric oxide synthase (INOS), endothelial nitric oxide synthase (EcNOS), ONOO− (Nitro, assayed by the amount of nitrated tyrosine residues), and apoptosis (TUNEL staining) were examined using immunohistochemistry. Increased expression for INOS, EcNOS, and ONOO− in both the loose/osteolytic and the loose/non‐osteolytic groups was observed when compared to the synovium group. There were no significant differences between the loose/osteolytic group and loose/non‐osteolytic group for these biologic markers. TUNEL staining showed a significant increase in apoptosis in the loose/osteolytic group compared to the loose/non‐osteolytic group and synovial tissues. These findings suggest that NO and NO‐derived molecules, such as ONOO−, may be involved in sustaining the foreign‐body reaction to wear debris. NO and ONOO− may prove to be useful markers of prosthetic loosening whereas apoptosis may be a marker distinguishing ballooning from simple osteolysis. © 2003 Wiley Periodicals, Inc. J Biomed Mater Res 66A: 541–549, 2003
An effective method for quantitative evaluation of proteins adsorbed on biomaterial surfaces
Authors: Lü X. Y. , Huang Y. , Qian W. P. , Tang Z. M. , Lu Z. H. 
Published: August 2003

AbstractAn effective method for the quantitative evaluation of proteins adsorbed on biomaterial surfaces has been developed. First, the kinetic behavior of a range of human fibrinogen (Fib) adsorbed onto polystyrene (PS) films was investigated by using a reflectometry interference spectroscopy setup. The specific molecular number of adsorbed proteins, Np, was then defined. According to the definition, the numbers of Fib molecules adsorbed on PS films were calculated. An atomic force microscope (AFM) was used to scan the lateral distribution of the Fib molecules adsorbed on the PS films. From the AFM images, the practical specific molecular numbers were obtained by direct counting of the molecules. In order that the adsorbed number of Fib molecules on a unit area of the PS films could be counted easily, the solution concentration of proteins was reduced to 5 ag/mL (10−18g/mL). There was good consistency between the numbers calculated with the formula defined by us and the numbers counted from AFM images. Therefore, the results of the present study prove the validity of our definition of the specific molecular number of adsorbed proteins and the effectiveness of the reflectometry interference spectroscopy‐based method for quantitative evaluation of adsorptive proteins. © 2003 Wiley Periodicals, Inc. J Biomed Mater Res 66A: 722–727, 2003
Novel therapeutic strategy for prevention of malignant tumor recurrence after surgery: Local delivery and prolonged release of adenovirus immobilized in photocured, tissue‐adhesive gelatinous matrix
Authors: Okino Hidenobu , Manabe Tatsuya , Tanaka Masao , Matsuda Takehisa 
Published: August 2003

AbstractWe have been developing a new gene delivery method using a styrenated gelatin‐based tissue‐adhesive matrix that allows in situ adenovirus‐immobilized gel formation on living tissue and sustained virus release to permeate carcinoma tissue. Styrenated gelatin was synthesized by the condensation reaction of gelatin with 4‐vinylbenzoic acid. Aqueous styrenated gelatin solution premixed with AdLacZ, adenovirus encoding β‐galactosidase cDNA, and carboxylated camphorquinone (CQ) as a photoinitiator was irradiated with visible light to form a styrenated gelatin gel. The in vitro adenovirus release from the styrenated gelatin gel to a medium strongly depended not on styrenated gelatin concentration but on CQ concentration. Maximal β‐galactosidase expression was observed on day 1, followed by a rapid decrease that continued up to 1 month for a styrenated gelatin gel prepared with a low styrenated gelatin concentration and a low CQ concentration. Dose‐dependent reduced expression of β‐galactosidase activity with increasing CQ under photoirradiation was observed. AdLacZ‐immobilized styrenated gelatin gel was formed on a hybrid tissue, which is a cell traction‐induced collagenous gel entrapped with fibroblasts, and lacZ gene expression of fibroblasts in the hybrid tissue was observed for more than one month. The result of this in vitro model experiment implies that the tissue‐adhesive styrenated gelatin may be applicable for the delivery of adenovirus encoding cDNA for tumor dormancy therapy into malignant tissue to prevent tumor recurrence after surgery when cDNA is properly selected. © 2003 Wiley Periodicals, Inc. J Biomed Mater Res 66A: 643–651, 2003
Biologic effects of surface roughness and fluorhydroxyapatite coating on osteointegration in external fixation systems: An in vivo experimental study
Authors: Savarino L. , Fini M. , Ciapetti G. , Cenni E. , Granchi D. , Baldini N. , Greco M. , Rizzi G. , Giardino R. , Giunti A. 
Published: August 2003

AbstractThe concomitant influence of surface roughness and fluorhydroxyapatite (FHA) coating of titanium (Ti) implants on bone response was investigated. For this purpose, titanium screw‐shaped implants with a lower degree (Y371) and a higher degree (TiPore300) of surface roughness, coated with FHA and uncoated, were transversally inserted into the diaphyses of sheep tibiae for 12 weeks. Four sheep received Y371 (group A) and Y371 + FHA (group B) screws and four sheep received TiPore300 (group C) and TiPore300 + FHA (group D) screws. For each type of material, the morphology and microstructure of implant–facing bone were evaluated. The host bone of each tibia was used as a control. In all groups the bone tissue did not reach a complete maturation. The higher degree of roughness, perhaps due to an excessive irregularity of the surface, induced the worst osteointegration: a fibrous tissue layer between screw and new bone tissue was often present. Nevertheless, as viewed by XRD, no crystallographic change of the apatite lattice was observed in any of the implants. In contrast, the microhardness value, an index of bone mineralization, was higher in the uncoated screws and decreased progressively in the following order: group C > group A > group B > group D. The association of plasma spraying with roughness treatment constitutes a complex system that seems to interfere with bone mineralization. A chemical change of the surface, perhaps with more Ti release or more coating degradation, could be responsible for such impairment. The authors emphasize the necessity for simultaneous evaluation of surface topography and chemistry as well as an improvement in plasma‐spraying and post‐processing techniques and in standard procedures for materials characterization. © 2003 Wiley Periodicals, Inc. J Biomed Mater Res 66A: 652–661, 2003
Enhancing mechanical properties of tissue‐engineered constructs via lysyl oxidase crosslinking activity
Authors: Elbjeirami Wafa M. , Yonter Edward O. , Starcher Barry C. , West Jennifer L. 
Published: August 2003

AbstractA number of strategies have been investigated to enhance the mechanical stability of engineered tissues. In this study, we utilized lysyl oxidase (LO) to enzymatically crosslink extracellular matrix (ECM) proteins, particularly collagen and elastin, to enhance the mechanical integrity of the ECM and thereby impart mechanical strength to the engineered tissue. Vascular smooth muscle cells (VSMCs) were liposomally transfected with the LO gene. Both Northern and Western analyses confirmed increased LO expression. Increased LO activity was demonstrated using a fluorescent enzyme substrate assay and by observation of the presence of increased levels of desmosine, a product of LO crosslinking, in the ECM. The mechanical effects of altered crosslink densities within tissue‐engineered constructs were demonstrated in a VSMC‐populated collagen gel model. When smooth muscle cells transfected with lysyl oxidase were seeded in collagen gels, the tensile strength and elastic modulus in these constructs increased by approximately two‐fold compared to constructs seeded with mock‐transfected VSMCs. Also, desmosine levels in the LO‐populated collagen gels were higher than they were in mock‐seeded gels, as demonstrated via immunohistochemical staining. Compositional analysis of the ECM deposited by the transformed cells showed similar collagen and elastin levels, and cell proliferation rates were similar as well, thus attributing increased mechanical properties to ECM crosslinking. © 2003 Wiley Periodicals, Inc. J Biomed Mater Res 66A: 513–521, 2003
Quantitative analysis of osteoblast behavior on microgrooved hydroxyapatite and titanium substrata
Authors: Lu Xiong , Leng Yang 
Published: August 2003

AbstractThe effects of implant surface topography and chemistry on osteoblast behavior have been a research focus because of their potential importance in orthopedic and dental applications. This work focused on the topographic effects of hydroxyapatite (HA) and titanium (Ti) surface that had identical micropatterns to determine whether there was synergistic interaction between surface chemistry and surface topography. Surface microgrooves with six different groove widths (4, 8, 16, 24, 30, and 38 μm) and three different groove depths (2, 4, and 10 μm) were made on single crystalline silicon wafers using microfabrication techniques. Ti and HA thin films were coated on the microgrooves by radio‐frequency magnetron sputtering. After that, human osteoblast‐like cells were seeded and cultured on the microgrooved surfaces for up to 7 days. The cells' behavior was examined using scanning electron microscopy after cells were fixed and dehydrated. Statistical analysis was based on quantitative data of orientation angle, evaluating the contact guidance, and form index, describing cell shape or cell morphology changes. The contact guidance and cell shape changes were observed on the HA and Ti microgrooves. No difference in orientation angle between HA and Ti microgrooves was found. This might suggest that surface chemistry was not a significant influence on cell guidance. However, the form index analysis indicated an interaction between topographic effects and surface chemistry. Thus, conclusions about surface topographic effects on cell behavior drawn from one type of material cannot simply be applied to another type of material. © 2003 Wiley Periodicals, Inc. J Biomed Mater Res 66A: 677–687, 2003
Novel in vivo method for evaluation of healing around implants in bone
Authors: Eriksson Cecilia , Broberg Marita , Nygren Håkan , Öster Lars 
Published: August 2003

AbstractA material implanted in bone is always inserted into coagulating blood. Protein and cell interactions during this initial implantation time will govern later healing. Many studies have focused on the tissue surrounding implants. We have developed a method for evaluation of healing around implants in bone by studying cells adhering to the implant surface. Hydrophilic titanium discs were inserted into rat tibiae. Samples were retrieved after 1, 2, 4, and 8 days of implantation and were analyzed by fluorescence microscopy techniques and scanning electron microscopy. Both proliferating and apoptotic cells were found on the surface. Generally, cells closest to the implant surface were nonviable whereas cells in the fibrin network a distance from the surface were viable. Bone morphogenetic protein‐2 (BMP‐2) is an osteogenic substance. An increase in BMP‐2‐positive cells was seen during the implantation period, and a population of large BMP‐2‐positive cells appeared on the surface after 4 days of implantation. The method developed here is a suitable tool for rapid evaluation of the initial healing around implant material. © 2003 Wiley Periodicals, Inc. J Biomed Mater Res 66A: 662–668, 2003