bluuebunny/crossref_metadata_2025_split huggingface dataset:
Structural design of the dry fibrin sealant dressing and its impact on the hemostatic efficacy of the product
Authors: Pusateri Anthony E. , Kheirabadi Bijan S. , Delgado Angel V. , Doyle James W. , Kanellos Jerry , Uscilowicz John M. , Martinez Raul S. , Holcomb John B. , Modrow Harold E. 
Published: April 2004

AbstractWe compared the hemostatic efficacy of a production version of a dry fibrin sealant dressing (DFSD) to a prototype that was previously successful in large animal studies. The results were used to improve manufacturing processes. Grade‐V liver injuries were induced in swine and treated with gauze sponges (GAU), the prototype dressings (DFSD‐1), or the scaled‐up production version dressings (DFSD‐2 in experiment 1 and DFSD‐3 in experiment 2). Blood loss, hemostasis, resuscitation volume, and 60‐min survival were quantified. In experiment 1, the DFSD‐1 treatment reduced blood loss (p < 0.01), increased hemostasis at 4 min (p < 0.05), and improved survival (p < 0.05) compared with GAU. The DFSHD‐2 decreased blood loss (p < 0.05) but did not increase hemostasis or survival significantly. Based on these results, manufacturing processes were altered, producing DFSD‐3. In experiment 2, the DFSD‐1 and DFSD‐3 were equally effective in reducing blood loss (p < 0.01) and resuscitation volume (p < 0.05) compared with GAU. Hemostasis occurred more frequently in both the DFSD‐1 and DFSD‐3 groups (p < 0.01) compared with GAU. The structural design of DFSD‐2 did not meet the efficacy requirement for release of the product. The subsequent change incorporated in DFSD‐3 improved all hemostatic parameters of the dressings equal to those of the prototype product. © 2004 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 70B: 114–121, 2004
Electrochemical properties of suprastructures galvanically coupled to a titanium implant
Authors: Oh Keun‐Taek , Kim Kyoung‐Nam 
Published: April 2004

AbstractIn recent years, dental implants have been widely used for the aesthetic and functional restoration of edentulous patients. Dental implants and restorative alloys are required with high corrosion resistance. Suprastructures and implants of different compositions in electrical contact may develop galvanic or coupled corrosion problems. In addition to galvanic corrosion, crevice and pitting corrosion may occur in the marginal gap between dental implant assemblies. In this study, gold, silver–palladium, cobalt–chromium, and nickel–chromium suprastructures were used to investigate their galvanic and crevice corrosion characteristics in combination with titanium (Ti) implants. Potentiodynamic and potentiostatic testing were performed in artificial saliva at 37°C. Potentiodynamic testing was carried out at the potential scan rate of 1 mV/s in the range of −600–1600 mV (SCE). Potentiostatic testing was performed with an open‐circuit potential and current densities at −250, 0, and 250 mV (SCE) in artificial saliva. After electrochemical testing, surface morphologies and cross‐sections were examined using micrographs of the samples. Potentiodynamic test results indicated that suprastructure/Ti implant couples produced passive current densities in the range of 0.5–12 μA/cm2; Ti abutment/Ti implant and gold/Ti implant couples exhibited relatively low passive current densities; Co–Cr/Ti implant couples the highest. Co–Cr and Ni–Cr/Ti implant couples showed breakdown potentials of 700 and 570 mV (SCE), respectively. The open‐circuit potentials of silver, Ti abutment, gold, Ni–Cr, and Co–Cr/Ti implant couples were −93.2 ± 93.9, −123.7 ± 58.8, −140.0 ± 80.6, −223.5 ± 35.1, and −312.7 ± 29.8 mV (SCE), respectively, and did not change with immersion time. The couples exhibited cathodic current densities at −250 mV (SCE); in particular, gold and silver alloys showed high cathodic current densities of −3.18 and −6.63 μA/cm2, respectively. At 250 mV (SCE), Ti abutment/Ti implant couples exhibited a minimum current density of 9.48 × 10−2 μA/cm2, but gold, Ni–Cr, Co–Cr, and silver/Ti implant couples exhibited 0.313, 1.27, 5.60, and 8.06 μA/cm2, respectively. All couples exhibited relatively low current densities at 0 mV (SCE). Photomicrographs after electrochemical testing showed crevice or pitting corrosion in the marginal gap and at the suprastructure surface. Although of the tested samples Co–Cr/Ti implant couples showed the possibility of galvanic corrosion, its degree was not significant. However, it should be borne in mind that galvanic corrosion can accelerate localized corrosion, such as crevice or pitting corrosion. © 2004 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 70B: 318–331, 2004
High release of antibiotic from a novel hydroxyapatite with bimodal pore size distribution
Authors: Hasegawa Masahiro , Sudo Akihiro , Komlev Vladimir S. , Barinov Serguei M. , Uchida Atsumasa 
Published: April 2004

AbstractWe developed a novel hydroxyapatite (HA) cylinder (HA‐A) and compared the slow release of antibiotic in vitro as well as osteoconduction of the material in vivo to a commercially produced porous hydroxyapatite cylinder (HA‐B). HA‐A (4 × 4 mm) was synthesized by mixing HA powder, gelatin, and vegetable oil. The material had a bimodal pore size distribution, with intragranular (10 nm to 10 μm) and intergranular (100 μm) pores, and porosity of 40 vol %, while HA‐B had pore sizes ranging from 50 to 300 μm and identical porosity. In vitro drug release was tested using antibiotics (isepamicin sulfate, vancomycin hydrochloride, and flomoxef sodium) soaked on the HA cylinders using a vacuum system. The mean adsorption efficiency was higher for HA‐A (46%) than for HA‐B (26%) and higher levels of antibiotic were released from HA‐A. Of the antibiotics, ISP showed the longest release duration. Bone ingrowth into the pores was observed for both materials. Because the novel HA showed both the slower release of antibiotic (nanosize pores) and supported excellent osteoconduction (microsize pores), it could be useful for the treatment of osteomyelitis. © 2004 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 70B: 332–339, 2004
3D microtomographic characterization of precision extruded poly‐ϵ‐caprolactone scaffolds
Authors: Darling A. L. , Sun W. 
Published: April 2004

AbstractOne of the dominant approaches to tissue engineering is the seeding of biodegradable, biocompatible polymer scaffolds with progenitor cells prior to 3D culture or implantation. The microarchitecture of these scaffolds has direct effects upon the ability of cells to attach, migrate, and differentiate. Microtomographic (micro‐CT) scanners enable high‐speed 3D characterization of the salient features of these polymer scaffolds. A micro‐CT scan followed by 3D reconstruction of serial image sections can determine porosity, pore size, pore interconnectivity, strut size, and overall 3D microarchitecture. In this study, four polymer samples with different microarchitectures were manufactured through precision extrusion deposition free‐form fabrication and subsequently characterized through micro‐CT analysis. A desktop micro‐CT scanner was used to examine each sample at approximately 19.1‐micron resolution. 2D analyses and 3D reconstructions of core regions of each sample were performed. These results illustrate that qualitative and quantitative analysis of polymer scaffolds is possible using micro‐CT and 3D reconstruction techniques. © 2004 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 70B: 311–317, 2004
Tissue‐specific regulation of leptin expression and secretion by all‐trans retinoic acid
Authors: Hollung Kristin , Rise Cecilie P. , Drevon Christian A. , Reseland Janne E. 
Published: April 2004

AbstractIn addition to hormones and the sympathetic nervous system, specific nutrients may regulate leptin mRNA expression and adipose tissue metabolism. However, little is known regarding the effect of nutrients on leptin mRNA expression. Retinoic acid (RA) is a ligand of some nuclear receptors and previous reports have demonstrated contradictive effects on plasma leptin levels. Thus, we examined the effect of RA on expression of leptin in adipocytes of murine and human origin. After 48 h incubation of murine 3T3‐L1 adipocytes with 1 and 10 μM all‐trans RA, the expression of leptin mRNA was reduced by 56% and 65%, respectively, whereas the secretion of leptin was reduced by 38% and 77%, respectively. In human adipose tissue explants, 1 μM all‐trans RA reduced leptin mRNA expression levels by 55% and leptin secretion by 25% after 24 h incubation. We observed an increased mRNA expression level of the transcription factors peroxisomal proliferator activated receptor γ (PPARγ), retinoid X receptor α (RXRα), and RA receptor α (RARα) in 3T3‐L1 cells, whereas the mRNA level of these transcription factors was unchanged in human adipose tissue explants after incubation with RA. In two other leptin‐expressing cell systems, the human placental throphoblast cell line BeWo and normal human primary osteoblasts, there was no effect of RA on leptin mRNA expression, but leptin secretion was reduced by 64% after 24 h incubation with 10 μM all‐trans RA in BeWo cells. In conclusion, all‐trans RA reduced both expression and secretion of leptin in human and rodent adipose tissue. In human BeWo cells or primary osteoblasts, leptin mRNA expression levels was not changed by all‐trans RA, indicating a tissue‐specific regulation of leptin mRNA expression by all‐trans RA. © 2004 Wiley‐Liss, Inc.
5‐azacytidine alters TGF‐β and BMP signaling and induces maturation in articular chondrocytes
Authors: Zuscik Michael J. , Baden Jonathan F. , Wu Qiuqian , Sheu Tzong J. , Schwarz Edward M. , Drissi Hicham , O'Keefe Regis J. , Puzas J. Edward , Rosier Randy N. 
Published: April 2004

AbstractMaintenance of the articular surface depends on the function of articular chondrocytes (ACs) which produce matrix and are constrained from undergoing the maturation program seen in growth plate chondrocytes. Only during pathologic conditions, such as in osteoarthritis, are maturational constraints lost causing recapitulation of the process that occurs during endochondral ossification. With the aim of establishing a model to identify regulatory mechanisms that suppress AC hypertrophy, we examined the capability of 5‐azacytidine (Aza) to have an impact on the maturational program of these cells. Primary ACs do not spontaneously express markers of maturation and are refractory to treatment by factors that normally regulate chondrocyte maturation. However, following exposure to Aza, ACs (i) were induced to express type X collagen (colX), Indian hedgehog, and alkaline phosphatase and (ii) showed altered colX and AP expression in response to bone morphogenetic protein‐2 (BMP‐2), transforming growth factor‐β (TGF‐β), and parathyroid hormone‐related protein (PTHrP). Since Aza unmasked responsiveness of ACs to BMP‐2 and TGF‐β, we examined the effect of Aza treatment on signaling via these pathways by assessing the expression of the TGF‐β Smads (2 and 3), the BMP‐2 Smads (1 and 5), and the Smad2 and 3‐degrading ubiquitin E3 ligase Smurf2. Aza‐treated ACs displayed less Smad2 and 3 and increased Smad1, 5, and Smurf2 protein and showed a loss of TGF‐β signaling on the P3TP‐luciferase reporter. Suggesting that Aza‐induction of Smurf2 may be responsible for the loss of Smad2 and 3 protein via this pathway, immunoprecipitation and metabolic labeling experiments confirmed that Aza accelerated the ubiquitination and degradation of these targets. Overall, Aza‐treated ACs represent a novel model for the study of mechanisms that regulate maturational potential of articular cartilage, with the data suggesting that maturation of these cells may be due to up‐regulation of Smad1 and 5 coupled with a Smurf2‐dependent degradation of Smad2 and 3 and loss of TGF‐β signaling. © 2004 Wiley‐Liss, Inc.
Regulation of neuroinflammation: The role of CXCL10 in lymphocyte infiltration during autoimmune encephalomyelitis
Authors: Klein Robyn S. 
Published: April 2004

AbstractThe movement of lymphocytes from the microvasculature into the central nervous system (CNS) parenchyma is an essential step in the pathogenesis of a variety of infectious and autoimmune neuroinflammatory diseases. The lymphocyte chemoattractant CXCL10 and its receptor, CXCR3, are expressed by the CNS and by CNS infiltrating lymphocytes, respectively, only in patients with ongoing CNS inflammation, suggesting an important role for these molecules in the pathogenic process. Numerous studies utilizing animal models and transgenic approaches have indeed supported a role for CXCL10 in the intraparenchymal trafficking of lymphocytes during acute CNS inflammation; however, other studies suggest that its expression is not required for the development of autoimmune forms of CNS inflammation and, in fact, that interference with CXCL10 signaling could lead to increased neuroinflammation. This review will consider the data from these studies and attempt to reconcile them through comparisons of both the neuroinflammatory models and the effects of CXCL10 in the CNS versus lymphoid tissues. Finally, it will define directions for future analyses of CXCL10 and CXCR3 in CNS inflammation so that their potential therapeutic utility can be more completely determined. © 2004 Wiley‐Liss, Inc.
Overexpression of regucalcin suppresses cell death in cloned rat hepatoma H4‐II‐E cells induced by tumor necrosis factor‐α or thapsigargin
Authors: Izumi Takako , Yamaguchi Masayoshi 
Published: April 2004

AbstractThe role of regucalcin, which is a regulatory protein in intracellular signaling pathway, in the regulation of cell death was investigated by using the cloned rat hepatoma H4‐II‐E cells overexpressing regucalcin. The hepatoma cells (wild‐type) and stable regucalcin (RC)/pCXN2 transfectants were cultured for 72 h in medium containing 10% fetal bovine serum (FBS) to obtain subconfluent monolayers. The proliferation of the cells was significantly suppressed in transfectants cultured for 72 h, as shown previously (Tsurusaki and Yamaguchi [2003]: J Cell Biochem 90:619–626). After culture for 72 h, cells were further cultured for 24–72 h in medium without FBS containing either vehicle, tumor necrosis factor‐α (TNF‐α; 0.1, 1, or 10 ng/ml) or thapsigargin (10−7–10−5 M). The number of wild‐type cells was significantly decreased by culture for 42 or 72 h in the presence of TNF‐α (0.1, 1, or 10 ng/ml) or thapsigargin (10−7–10−5 M). The effect of TNF‐α (0.1 or 1 ng/ml) or thapsigargin (10−7 or 10−6 M) in decreasing the number of hepatoma cells was significantly prevented in transfectants overexpressing regucalcin. The presence of TNF‐α (10 ng/ml) or thapsigargin (10−5 M) caused a significant decrease in cell number of transfectants. Ca2+/calmodulin‐dependent nitric oxide (NO) synthase activity in wild‐type cells was significantly increased by culture with TNF‐α (10 ng/ml) for 48 or 72 h. This increase was significantly prevented in transfectants. Culture with thapsigargin (10−5 M) caused a significant increase in Ca2+/calmodulin‐dependent NO synthase activity in wild‐type cells or transfectants. TNF‐α‐induced decrease in the number of wild‐type cells was significantly prevented by culture with Nω‐nitro‐l‐arginine (10−4 M), an inhibitor of caspase. Agarose gel electrophoresis showed the presence of low‐molecular‐weight deoxyribonucleic acid (DNA) fragments of adherent wild‐type cells cultured with thapsigargin (10−6 M), and this DNA fragmentation was not suppressed by culture with caspase inhibitor. Thapsigargin‐induced DNA fragmentation was significantly suppressed in transfectants cultured with or without caspase inhibitor. This study demonstrates that overexpression of regucalcin has a suppressive effect on cell death induced by TNF‐α or thapsigargin. © 2004 Wiley‐Liss, Inc.
Flavonoid quercetin decreases osteoclastic differentiation induced by RANKL via a mechanism involving NFκB and AP‐1
Authors: Wattel Alice , Kamel Said , Prouillet Christophe , Petit Jean‐Pierre , Lorget Florence , Offord Elizabeth , Brazier Michel 
Published: April 2004

AbstractFlavonoids are micronutrients widely present in food of plant origin. They have been attributed pharmacological properties such as anticancer and prevention of age‐related pathologies. It has been recently hypothesized that flavonoids increase bone mass and prevent osteoporosis. However, little is known about the in vitro effects of flavonoids on osteoclast activities. We investigated the effects of quercetin, one of the most commonly occurring flavonoids, on osteoclast differentiation which is a critical determinant step of in vivo bone resorption. Two in vitro models of osteoclast differentiation were used in this study: a murine one, involving the culture of RAW 264.7 cells in presence of receptor activator of NFκB ligand (RANKL), and a human model consisting of differentiating peripheral blood monocytic cells (PBMC) isolated from peripheral blood in presence of RANKL and macrophage‐colony stimulating factor (M‐CSF). Osteoclastogenesis was assessed by osteoclast‐like number, tartrate resistant acid phosphatase (TRAP) activity, and bone resorbing activity. We showed that quercetin (0.1–10 μM) decreased osteoclastogenesis in a dose dependent manner in both models with significant effects observed at low concentrations, from 1 to 5 μM. The IC50 value was about 1 μM. Analysis of protein–DNA interaction by electrophoretic mobility shift assay (EMSA) performed on RAW cells showed that a pre‐treatment with quercetin inhibited RANKL‐induced nuclear factor kB (NFκB) and activator protein 1 (AP‐1) activation. NFκB and AP‐1 are transcription factors highly involved in osteoclastic differentiation and their inhibition could play an important role in the decrease of osteoclastogenesis observed in the presence of quercetin. In conclusion, the present results demonstrate for the first time that quercetin, a flavonoid characterized by antioxidant activities, is a potent inhibitor of in vitro osteoclastic differentiation, via a mechanism involving NFκB and AP‐1. © 2004 Wiley‐Liss, Inc.
Therapist affirmation and the process and outcome of psychotherapy: Two sequential analytic studies
Authors: Karpiak Christie P. , Benjamin Lorna Smith 
Published: April 2004

AbstractTherapist affirmation was examined in two studies, the first with cognitive‐behavioral therapy (CBT, N = 22) and the second with time‐limited dynamic psychotherapy (TLDP, N = 20). Affirmation was identified using Structural Analysis of Social Behavior (SASB), and sequential analysis used to gauge its impact on therapy process and outcome. It was hypothesized that affirmation would correspond with patients' continuation of the current topic of conversation, but relate negatively to outcome if generally offered after maladaptive statements. Patients in Study 1 (CBT) were more likely to continue a topic after it was affirmed, and affirmation of maladaptive statements reliably differentiated patients who evidenced clinically significant change from those who did not at termination and at 12‐months posttreatment. Affirmation of maladaptive statements in Study 2 (TLDP) corresponded with poorer outcome in relationships with significant others, but unexpectedly with improvements in self‐concept. © 2004 Wiley Periodicals, Inc. J Clin Psychol.
Psychological mindedness and cognitive style
Authors: Beitel Mark , Ferrer Elena , Cecero John J. 
Published: April 2004

AbstractPsychological mindedness (PM) is theorized to be a cognitively toned personality variable, yet, there is a paucity of research addressing the cognitive components of PM. This study was intended to redress this issue by testing the empirical associations between PM and Ambiguity Tolerance, as measured by the Revised Scale for Ambiguity Tolerance (MacDonald, 1970); Locus of Control, as measured by the Locus of Control Scale (Rotter, 1966); and Magical Thinking, as measured by the Magical Ideation Scale (Eckblad & Chapman, 1983). The results indicated that PM is positively associated with ambiguity tolerance, whereas it is inversely related to external locus of control and magical thinking. These findings suggest a cognitive style profile for PM that includes flexibility, a sense of personal agency, and a propensity for realistic thinking. High‐PM individuals are likely to bring these cognitive resources to bear in psychotherapy, a tendency that might explain why high PM patients make better use of treatment. © 2004 Wiley Periodicals, Inc. J Clin Psychol.
Microencapsulation of tannase by chitosan–alginate complex coacervate membrane: synthesis of antioxidant propyl gallate in biphasic media
Authors: Yu Xiaowei , Li Yongquan , Wu Dan 
Published: April 2004

AbstractTannase microencapsulated by a chitosan–alginate complex coacervate membrane has been used for synthesis of the food additive antioxidant, propyl gallate. Matrix experiments using standard L9 orthogonal array were used to evaluate the effects of the microencapsulation process on the synthesis of propyl gallate in biphasic media. The statistical analysis of signal‐to‐noise ratio and decomposition of variance (ANOVA) were performed to estimate the optimum levels and determine the relative magnitude of the effects of the three control factors which were chitosan, alginate and hardening time. The optimized capsule for synthesis was formed by dropwise addition of a 15 kg m−3 chitosan and 20 kg m−3 CaCl2 solution into a 14 kg m−3 alginate solution, stirred for 20 min, then hardened for 30 min in 20 kg m−3 CaCl2. Copyright © 2004 Society of Chemical Industry
Enhanced bioremediation of crude oil‐contaminated soil by a Pseudomonas species and mutually associated adapted Azotobacter vinelandii
Authors: Onwurah Ikechukwu NE , Nwuke Chinedu 
Published: April 2004

AbstractA mixed culture of compatible hydrocarbonoclastic and diazotrophic bacteria, each at a density of 108 organisms cm−3, was developed for optimised bioremediation of crude oil‐contaminated soil. The hydrocarbonoclastic bacterium, Pseudomonas sp and the diazotroph, Azotobacter vinelandii, were both isolated from a previously crude oil‐contaminated soil and thereafter modelled as a unit of mutualistic consortium in situ. Stabilisation of the consortium and hence the optimised bioremediation process occurred when the bacterial growth attained a pseudo‐steady state condition. This was considered to be as a result of a symbiotic association between A vinelandii and the Pseudomonas sp in which A vinelandii produced the required concentration of fixed nitrogen compounds required for the growth of the Pseudomonas sp. Enhancement in biodegradation, due to stimulated growth of Pseudomonas sp and co‐metabolic activity of A vinelandii, was mathematically evaluated as the difference in the specific growth rates (µ) between the consortium Pseudomonas sp/A vinelandii and Pseudomonas sp alone. The proportion of petroleum hydrocarbons degraded by the consortium from the contaminated soil ranged between 66.83 and 69.6% as compared with that of a pure culture of Pseudomonas sp (23.2–44.45%). Hence, beyond their role in biological nitrogen fixation, diazotrophs may be used to contribute to bioremediation of crude oil‐contaminated land. Copyright © 2004 Society of Chemical Industry