bluuebunny/crossref_metadata_2025_split huggingface dataset:
Fabrication, characterization, and biocompatibility of single‐walled carbon nanotube‐reinforced alginate composite scaffolds manufactured using freeform fabrication technique
Authors: Yildirim Eda D. , Yin Xi , Nair Kalyani , Sun Wei 
Published: May 2008

AbstractComposite polymeric scaffolds from alginate and single‐walled carbon nanotube (SWCNT) were produced using a freeform fabrication technique. The scaffolds were characterized for their structural, mechanical, and biological properties by scanning electron microscopy, Raman spectroscopy, tensile testing, and cell–scaffold interaction study. Three‐dimensional hybrid alginate/SWCNT tissue scaffolds were fabricated in a multinozzle biopolymer deposition system, which makes possible to disperse and align SWCNTs in the alginate matrix. The structure of the resultant scaffolds was significantly altered due to SWCNT reinforcement, which was confirmed by Raman spectroscopy. Microtensile testing presented a reinforcement effect of SWCNT to the mechanical strength of the alginate struts. Ogden constitutive modeling was utilized to predict the stress–strain relationship of the alginate scaffold, which compared well with the experimental data. Cellular study by rat heart endothelial cell showed that the SWCNT incorporated in the alginate structure improved cell adhesion and proliferation. Our study suggests that hybrid alginate/SWCNT scaffolds are a promising biomaterial for tissue engineering applications. © 2008 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2008
Photocatalytic and antibacterial properties of medical‐grade PVC material coated with TiO2 film
Authors: Lin Huaxiang , Xu Ziting , Wang Xuxu , Long Jinlin , Su Wenyue , Fu Xianzhi , Lin Qun 
Published: May 2008

AbstractThe TiO2 film was coated on poly vinyl chloride (PVC) surface by dip‐coating process from TiO2–PVC–THF suspension. The morphology and crystal structure of the as‐synthesized samples were characterized by SEM and XRD. The photocatalytic properties were measured by the photodegradation reaction of RhB and the anti‐adhesion and anti‐bacteria for Escherichia coli. The results show that the resultant TiO2 film is well‐conglutinated on PVC surface and has the same crystal structure as the original TiO2 powder. The TiO2/PVC shows excellent photocatalytic activity for the degradation of aqueous RhB and the activity increases with increasing reaction time and tends toward stable after accumulative illumination for 11.5 h. The TiO2 film shows good bacterial anti‐adhesion activity following photo‐activation and sterilization property under UV irradiation. The E. coli can be killed completely after UV irradiation for 1.5 h. © 2008 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 87B: 425–431, 2008
Remaining unreacted methacrylate groups in resin‐based composite with respect to sample preparation and storing conditions using micro‐Raman spectroscopy
Authors: Miletic Vesna J. , Santini Ario 
Published: May 2008

AbstractThe aim of this study was to measure degree of conversion (DC) of resin‐based composites (RBCs) using micro‐Raman spectroscopy followed by different sample preparation procedures and storing conditions. Ninety samples of Tetric EvoCeram (Ivoclar Vivadent, Schaan, Liechtenstein) were prepared in standardized molds and cured with a high powered LED light‐curing unit, bluephase® (Ivoclar Vivadent, Schaan, Liechtenstein) for 20 s. Samples were allocated to eight groups. DC of groups 1 and 2 was recorded without or after polishing. DC in groups 3 and 4 was recorded from vertically sectioned samples versus “split” samples. DC in groups 5–8 was recorded after storing samples at room temperature and humidity, in 90 ± 2% humidity at 37 ± 1°C, distilled water at 37 ± 1°C or buffered incubation medium (BIM) at 37 ± 1°C for 24 h. Mean values of DC in polished and unpolished samples were 63.6% (±3.2%) and 54.7% (±5.2%), respectively (p < 0.0001). There was no significant difference in DC after sample‐sectioning (p > 0.05). Significantly higher DC values were obtained after storing samples in BIM (76.8% ± 2.1%) than in distilled water (59.7% ± 5.7%), extreme humidity (60.3% ± 3.9%) or in room conditions (63.6% ± 3.2%) (p < 0.001). DC of an RBC measured by micro‐Raman spectroscopy may be affected by differences in sample preparation and storing conditions, making it difficult to extrapolate data from in vitro studies into clinically relevant information. © 2008 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2008
Bisphosphonate‐laden acrylic bone cement: Mechanical properties, elution performance, and in vivo activity
Authors: Yu Nicole Y. C. , Ruys Andrew J. , Zenios Michalis , Godfrey Craig , McDonald Michelle , Kiely Patrick , Mikulec Kathy , Little David G. , Schindeler Aaron 
Published: May 2008

AbstractCemented total hip replacements generally fail after 10–20 years, often due to implant loosening from bone resorption. Bisphosphonates such as zoledronic acid (ZA) and pamidronate (PAM) are potent inhibitors of bone resorption. The local delivery of bisphosphonates via acrylic bone cement could decrease osteolysis and prolong implant lifespan. Conflicting studies suggest that bisphosphonate loading may or may not reduce the mechanical properties of acrylic bone cement. We assayed acrylic bone cement laden with ZA or PAM at different concentrations and diluent volumes. Four‐point bend testing and compressive testing indicated that high volumes of diluent (with or without bisphosphonate) significantly reduced bending modulus and compressive strength. Radiography and electron microscopy indicated that high diluent volumes generated abnormal acrylic bone cement structure. After 6 weeks of incubation in saline, only 0.9% w/w of the total bisphosphonate incorporated in acrylic bone cement eluted in vitro, indicating a slow elution rate. In vivo testing was performed using a rat model. Cement cylinders were inserted into incisions in rat distal femora and ZA delivered locally (via elution from acrylic bone cement) or systemically (via injection). At 4 weeks postoperatively, dual energy X‐ray absorptiometry demonstrated no significant increase in local bone mineral density (BMD) adjacent to ZA‐laden implants. In contrast, systemic ZA delivery (0.1 mg/kg) led to a large (48.6%) and significant increase in BMD. Thus, systemic delivery appears more effective than local delivery. © 2008 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2008
The distribution of crystalline material in obstructed stents—In need for intra‐luminal surface modification?
Authors: Laube Norbert , Kleinen Lisa , Avrutin Vadym , Böde Ulla , Meißner Andreas , Fisang Christian 
Published: May 2008

AbstractPurpose: Usually, hampered urine flow and failing of Seldinger technique leads to the explanation “obstructed ureteral stent” with no further clarification where exactly the obstructions are located. If stent obstruction is caused by intra‐luminal biofilm and/or crystal deposits, the need of biofilm reducing coatings on the stent's inside has to be discussed. Materials and Methods: We investigated 59 stents from patients in whom acute hydronephrosis and/or acute pyelonephritis required stent replacement and/or usage of Seldinger technique failed. The stents were investigated by X‐ray and, after longitudinal cutting, by light‐microscopy for occurrence of obstructing material. Results: The inside of 25% of the samples was lined with a thick film composed of blood clots and tiny non‐aggregated crystals. Only in these samples X‐ray investigation showed a positive result for massive inner encrustations, which in fact may be responsible for stent occlusion. 48% of the stents contained few small domains composed of blood clots and crystals. 27% of the stent samples showed no alteration. Conclusions: 75% of the “obstructed” stents showed no significant inner deposits. Obstruction of urine transport and failure of Seldinger technique occurred due to other reasons. Thus, coating of the stent's inner surface may be overrated. © 2008 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2008
Change in cell shape is required for matrix metalloproteinase‐induced epithelial‐mesenchymal transition of mammary epithelial cells
Authors: Nelson Celeste M. , Khauv Davitte , Bissell Mina J. , Radisky Derek C. 
Published: May 2008

AbstractCell morphology dictates response to a wide variety of stimuli, controlling cell metabolism, differentiation, proliferation, and death. Epithelial‐mesenchymal transition (EMT) is a developmental process in which epithelial cells acquire migratory characteristics, and in the process convert from a “cuboidal” epithelial structure into an elongated mesenchymal shape. We had shown previously that matrix metalloproteinase‐3 (MMP3) can stimulate EMT of cultured mouse mammary epithelial cells through a process that involves increased expression of Rac1b, a protein that stimulates alterations in cytoskeletal structure. We show here that cells treated with MMP‐3 or induced to express Rac1b spread to cover a larger surface, and that this induction of cell spreading is a requirement of MMP‐3/Rac1b‐induced EMT. We find that limiting cell spreading, either by increasing cell density or by culturing cells on precisely defined micropatterned substrata, blocks expression of characteristic markers of EMT in cells treated with MMP‐3. These effects are not caused by general disruptions in cell signaling pathways, as TGF‐β‐induced EMT is not affected by similar limitations on cell spreading. Our data reveal a previously unanticipated cell shape‐dependent mechanism that controls this key phenotypic alteration and provide insight into the distinct mechanisms activated by different EMT‐inducing agents. J. Cell. Biochem. 105: 25–33, 2008. © 2008 Wiley‐Liss, Inc.
Interplay between anion‐π and hydrogen bonding interactions
Authors: Escudero Daniel , Frontera Antonio , Quiñonero David , Deyà Pere M. 
Published: May 2008

AbstractThe interplay between two important noncovalent interactions involving aromatic rings is studied by means of high levelab initiocalculations. They demonstrate that synergistic effects are present in complexes where anion‐π and hydrogen bonding interactions coexist. These synergistic effects have been studied using the “atoms‐in‐molecules” theory and the Molecular Interaction Potential with polarization partition scheme. The present study examines how these two interactions mutually influence each other. © 2008 Wiley Periodicals, Inc. J Comput Chem, 2009
Family history of psychological problems in generalized anxiety disorder
Authors: McLaughlin Katie A. , Behar Evelyn , Borkovec T.D. 
Published: May 2008

AbstractThe current investigation examined self‐reported family history of psychological problems in a large sample of individuals diagnosed with generalized anxiety disorder (GAD) and nonanxious controls. The GAD participants were all individuals receiving cognitive–behavioral therapy as part of two large randomized clinical trials. Family history information was obtained from the Anxiety Disorders Interview Schedule‐Revised (ADIS‐R; DiNardo & Barlow, 1988). The results indicate that, compared to control participants, individuals with GAD were more likely to have family members with anxiety problems, but not other psychological problems. Possible mechanisms for the familial transmission of GAD are discussed. © 2008 Wiley Periodicals, Inc. J Clin Psychol 64: 1–14, 2008.
Sox9, a key transcription factor of bone morphogenetic protein‐2‐induced chondrogenesis, is activated through BMP pathway and a CCAAT box in the proximal promoter
Authors: Pan Qiuhui , Yu Yongchun , Chen Qiongyu , Li Chunsheng , Wu Hong , Wan Yang , Ma Ji , Sun Fenyong 
Published: May 2008

AbstractMouse embryonic fibroblasts (MEFs) can be differentiated into fully functional chondrocytes in response to bone morphogenetic protein‐2 (BMP‐2). The expression of Sox9, a critical transcription factor for the multiple steps of chondrogenesis, has been reported to be upregulated during this process. But the molecular mechanisms by which BMP‐2 promotes chondrogenesis still remain largely unknown. The aim of the present study was therefore to investigate the underlying mechanism. In the MEFs, BMP‐2 efficiently induced Sox9 expression along with chondrogenic differentiation in a time‐ and dose‐dependent manner. SB203580, a specific inhibitor for p38 pathway, blocked BMP‐2‐induced chondrogenic differentiation as well as Sox9 expression and its transactivation of downstream genes. Forced expression of Smad6, a natural antagonist for BMP/Smad pathway, only inhibited Sox9 protein function without rendering any effects on its mRNA expression. A CCAAT box was identified in Sox9 promoter as thecis‐elements responsible for BMP‐2 stimulation. This study provides insight into the mechanisms underlying BMP‐2‐regulated Sox9 expression and activity in MEFs, and suggests differential roles of BMP‐2/p38 and BMP‐2/Smad pathways in modulating the function of Sox9 during chondrogenesis. J. Cell. Physiol. 217: 228–241, 2008. © 2008 Wiley‐Liss, Inc.
Age‐dependent impairment of HIF‐1α expression in diabetic mice: Correction with electroporation‐facilitated gene therapy increases wound healing, angiogenesis, and circulating angiogenic cells
Authors: Liu Lixin , Marti Guy P. , Wei Xiaofei , Zhang Xianjie , Zhang Huafeng , Liu Ye V. , Nastai Manuel , Semenza Gregg L. , Harmon John W. 
Published: May 2008

AbstractWound healing is impaired in elderly patients with diabetes mellitus. We hypothesized that age‐dependent impairment of cutaneous wound healing in db/db diabetic mice: (a) would correlate with reduced expression of the transcription factor hypoxia‐inducible factor 1α (HIF‐1α) as well as its downstream target genes; and (b) could be overcome by HIF‐1α replacement therapy. Wound closure, angiogenesis, and mRNA expression in excisional skin wounds were analyzed and circulating angiogenic cells (CACs) were quantified in db/db mice that were untreated or received electroporation‐facilitated HIF‐1α gene therapy. HIF‐1α mRNA levels in wound tissue were significantly reduced in older (4–6 months) as compared to younger (1.5–2 months) db/db mice. Expression of mRNAs encoding the angiogenic cytokines vascular endothelial growth factor (VEGF), angiopoietin 1 (ANGPT1), ANGPT2, platelet‐derived growth factor B (PDGF‐B), and placental growth factor (PLGF) was also impaired in wounds of older db/db mice. Intradermal injection of plasmid gWIZ‐CA5, which encodes a constitutively active form of HIF‐1α, followed by electroporation, induced increased levels of HIF‐1α mRNA at the injection site on day 3 and increased levels of VEGF, PLGF, PDGF‐B, and ANGPT2 mRNA on day 7. CACs in peripheral blood increased 10‐fold in mice treated with gWIZ‐CA5. Wound closure was significantly accelerated in db/db mice treated with gWIZ‐CA5 as compared to mice treated with empty vector. Thus, HIF‐1α gene therapy corrects the age‐dependent impairment of HIF‐1α expression, angiogenic cytokine expression, and CACs that contribute to the age‐dependent impairment of wound healing in db/db mice. J. Cell. Physiol. 217: 319–327, 2008. © 2008 Wiley‐Liss, Inc.
Potential of Monoraphidium sp. GK12 for energy‐saving astaxanthin production
Authors: Fujii Katsuhiko , Nakajima Hisatoshi , Anno Yuka 
Published: May 2008

AbstractBACKGROUND: Astaxanthin is a chemical used in aquaculture, pharmaceuticals, foods, and cosmetics. Although Haematococcus pluvialis has been studied intensively as an astaxanthin producer, its cultivation requires stringent contamination control and nutrition levels, thus rendering astaxanthin production energy‐consuming. In the present study, the medium composition for cultivation of Monoraphidium sp. GK12, a newly isolated astaxanthin‐producing microalga, was improved and photoautotrophic cultivation was attempted to examine its potential for application to energy‐saving astaxanthin production.RESULTS: A cost‐saving medium composed only of mineral salts was found to be suitable for photoautotrophic GK12 cultivation. A specific growth rate of 0.57 day−1 was obtained, which is higher than that of H. pluvialis. A high cell density of around 2.0 × 107 cells mL−1 was accomplished in outdoor batch cultivation, while outgrowth of contaminants was not observed. GK12 was also cultivated in a continuous photobioreactor, and the introduction of 1% CO2 stimulated GK12 growth and astaxanthin productivity.CONCLUSION: Control of temperature, illumination, and culture pH is unnecessary for GK12 outdoor cultivation and no outgrowth of contaminants was observed, suggesting an advantage over H. pluvialis outdoor cultivation. Besides improving Haematococcus cultivation methods, research on GK12 as an alternative astaxanthin‐producer may contribute to the establishment of energy‐saving astaxanthin production. Copyright © 2008 Society of Chemical Industry
Combined use of waste materials—recovery of chitin from shrimp shells by lactic acid fermentation supplemented with date juice waste or glucose
Authors: Adour Lydia , Arbia Wassila , Amrane Abdeltif , Mameri Nabil 
Published: May 2008

AbstractBACKGROUND: Chitin, a source of chitosan, was extracted from the teguments of white shrimp Parapenaeus longirostris, by means of Lactobacillus helveticus growing on date juice waste or glucose for comparison. A fermentor containing 10% (w/v) of shrimp shells was inoculated with a suspension of L. helveticus strain milano (10% v/v).RESULTS: For an initial pH of 8.5–9.0 and a temperature of 30 °C, maximum deproteinization and demineralization were 76 and 53%, achieved for 80 and 300 g L−1 glucose, respectively. The level of demineralization increased to 60% for an increase in in temperature from 30 to 35 °C. The use of date juice, as an alternative to the use of a primary carbon source such as glucose, led at best to 44% demineralization, for 208 g L−1 of total sugar at 35 °C, and 91% deproteinization, for 80 g L−1 total sugar content at 30 °C.CONCLUSION: Demineralization was not improved by the use of date juice, most likely due to its calcium content, which, during acidification, prevents the diffusion of calcium from the shells to the surrounding medium. Contrarily, the proteolytic activity of LAB appeared to be improved by the mineral content of date juice, leading to almost complete deproteinization of shrimp shells. Copyright © 2008 Society of Chemical Industry
Effect of dye auxiliaries on the kinetics of advanced oxidation UV/H2O2 of Acid Orange 7 (AO7)
Authors: Anglada Ángela , Rivero María J. , Ortíz Inmaculada , Urtiaga Ane 
Published: May 2008

AbstractBACKGROUND: The effect of four dye‐auxiliary chemicals, typically employed in acid dyeing, on the performance of UV/H2O2 decolouration of the model non‐biodegradable dye C.I. Acid Orange 7 (AO7) was investigated. The initial concentration of AO7 was 0.150 g L−1, while the concentration of the auxiliary compounds (NaCl, Na2SO4, Na2CO3 and CH3COOH) was varied in the range 1–10 g L−1.RESULTS: The negative influence of the presence of the dye‐auxiliary compounds studied on the decolouration rate of AO7 decreased in the following order: CH3COOH > Na2SO4 > NaCl > Na2CO3. Results were quantified in terms of the observed kinetic rate constant, kobs (s−1), of AO7 decolouration as a function of dye auxiliary chemical concentration. The decolouration rate of AO7 decreased as the concentration of dye‐auxiliary compound increased in the range 1–5 g L−1, while higher concentrations had a minor effect. Upon addition of 5 g L−1 of CH3COOH, NaCl and Na2SO4, the kinetic rate constant decreased by 39%, 30% and 12%, respectively.CONCLUSIONS: It was concluded that the presence of NaCl, Na2SO4 and above all of CH3COOH should be considered in the design of the treatment of real dye‐bath effluents by UV/H2O2. Copyright © 2008 Society of Chemical Industry
RNAi‐mediated reversible opening of the blood‐brain barrier
Authors: Campbell Matthew , Kiang Anna‐Sophia , Kenna Paul F. , Kerskens Christian , Blau Christoph , O'Dwyer Laurence , Tivnan Amanda , Kelly Julie Anne , Brankin Brenda , Farrar Gwyneth‐Jane , Humphries Peter 
Published: May 2008

AbstractBackgroundThe blood‐brain barrier (BBB) contains tight junctions (TJs) which reduce the space between adjacent endothelial cells lining the fine capillaries of the microvasculature of the brain to form a selective and regulatable barrier.MethodsUsing a hydrodynamic approach, we delivered siRNA targeting the TJ protein claudin‐5 to the endothelial cells of the BBB in mice.ResultsWe have shown a significant decrease in claudin‐5 mRNA levels 24 and 48 hours post‐delivery of siRNA, with levels of protein expression decreasing up to 48 hours post‐injection compared to uninjected, phosphate‐buffered saline (PBS)‐injected and non‐targeting siRNA‐injected mice. We observed increased permeability at the BBB to molecules up to 742 Da, but not 4400 Da, using tracer molecule perfusion and MRI analysis. To illustrate the functional efficacy of size‐selective and transient barrier opening, we have shown that enhanced delivery of the small neuropeptide thyrotropin‐releasing hormone (TRH) (MW 360 Da) to the brains of mice 48 hours post‐injection of siRNA targeting claudin‐5 significantly modifies behavioural output.ConclusionsThese data demonstrate that it is now possible to transiently and size‐selectively open the BBB in mice, allowing in principle the delivery of a wide range of agents for the establishment and treatment of experimental mouse models of neurodegenerative, neuropsychiatric and malignant diseases. Copyright © 2008 John Wiley & Sons, Ltd.
TLM nodal state estimator: An alternative method of initializing a two‐dimensional diffusion model
Authors: Koay A. L. , Wilkinson A. J. , Pulko S. H. 
Published: May 2008

AbstractThe transmission line matrix (TLM) method is an established technique for modelling thermal transients in heat transfer systems. However, initial and boundary conditions have always been slightly problematic, particularly when the boundary condition is specified as a temperature (Transmission Line Matrix (TLM) Techniques for Diffusion Applications. Gordon & Breach: London, 1998), for example, when the body of interest is suddenly exposed to a different temperature on its surface. In such a case the modelled solution contains additional dynamics that are associated with the two sub‐meshes in the TLM network and the two timesteps necessary for the temperature change to be fully communicated. These initialization problems are related to the fact that the boundary temperature in merely imposed as a fixed value on the network; the fundamental information‐carrying quantity, on the other hand, is the pulse, the thermal state of the body being represented by the distribution of pulses. Here, we aim to provide an alternative initialization approach, using nodal state estimation to derive pulse distributions from boundary and initial conditions specified by temperature. Consideration is given to the accuracy of the estimator by comparison with the first timestep solution proposed by Enders (Int. J. Numer. Model. 2002; 15:251–259). Copyright © 2008 John Wiley & Sons, Ltd.