bluuebunny/crossref_metadata_2025_split huggingface dataset:
Perceptive research on wheat evapotranspiration in Pakistan
Authors: Laghari K. Q. , Lashari B. K. , Memon H. M. 
Published: June 2008

AbstractThe Mehran model is developed based on the FAO‐56 modified Penman–Monteith equation for computing reference and crop evapotranspiration with dual crop coefficients. Evapotranspiration (ET) of wheat in three field experiments with management‐allowed depletion (MAD) of 45, 55 and 65% was observed through gypsum block readings and a drainage lysimeter. The seasonal crop ETs were observed as 363, 359 and 332 mm, and were computed as 383, 369 and 355 mm. The corresponding water use efficiencies (WUEs) were ascertained as 14.1, 15.0 and 13.4 kg (ha mm)−1. The highest crop WUE was achieved with MAD at 55%; therefore, this research is more focused upon in the paper. The model relatively overestimated seasonal ET by 2.8%. Weekly root length and daily soil‐moisture measurements revealed that wheat extracts most of its moisture from the 0–50 cm soil profile. When practising either scientific or traditional irrigation scheduling in the country, a seasonal water amount of 370 mm is suggested for wheat to achieve optimum yield and WUE.Statistical analysis (R2 = 0.90, T = 2.09, and F = 999) showed good correlation between computed and actual seasonal ETs of crop with an experimental MAD of 55%. The Mehran model is found to be quite versatile and can be successfully used as a decision support system (DSS) for irrigation scheduling of wheat in Pakistan. Copyright © 2008 John Wiley & Sons, Ltd.
In vivo evaluation of bonding ability and biocompatibility of a novel biodegradable glue consisting of tartaric acid derivative and human serum albumin
Authors: Iwasashi Masashi , Sakane Masataka , Saito Hirofumi , Taguchi Tetsushi , Tateishi Tetsuya , Ochiai Naoyuki 
Published: June 2008

AbstractWe recently developed a novel biological glue from tartaric acid derivative (TAD) with two active ester groups and human serum albumin (HSA), named TAD‐A. In this study, in vivo experiments were performed to investigate clinical applicability of TAD‐A. TAD was prepared by reacting carboxyl groups of tartaric acid with N‐hydroxysuccinimide in the presence of carbodiimide. Bonding strength was evaluated by using mouse skin closed with TAD‐A of different TAD concentrations from 0.1 to 0.5 mmol in 0.8 mg of 44 w/w % HSA solution. Commercially available glues such as fibrin and aldehyde‐based glue were used for comparison. We found that TAD‐A's bonding strength increased significantly with TAD‐A concentration. The bonding strength of 0.5 mmol of TAD‐A in 0.8 mg of 44 w/w % HSA solution was significantly higher than that of fibrin or aldehyde‐based glue (p < 0.01), and that of 0.3 mmol of TAD‐A was significantly higher than of fibrin glue (p < 0.05). To determine toxicity, we implanted disks made from TAD‐A of different TAD concentrations from 0.1 to 0.5 mmol in 0.8 mg of 44 w/w % HSA solution subcutaneously in mice. The inflammatory reaction in surrounding tissue increased with increasing TAD concentration, and then the disks were absorbed. In conclusion, TAD‐A has sufficient bonding strength and comparatively low toxicity in clinical use of 0.3 mmol or less of TAD and 0.8 mL of 44 w/w % HSA solution. © 2008 Wiley Periodicals, Inc. J Biomed Mater Res, 2009
pH‐dependent self‐assembling behavior of imidazole‐containing polyaspartamide derivatives
Authors: Seo Kwangwon , Kim Jong‐Duk , Kim Dukjoon 
Published: June 2008

AbstractA series of pH‐sensitive polyaspartamide derivatives were prepared by grafting 1‐(3‐aminopyl)imidazole (API) and O‐(2‐aminoethyl)‐O′‐methylpolyethylene glycol (MPEG, Mw:5000), as a pH sensitive moiety and hydrophilic group, respectively. The effect of the polymer composition was examined. The UV transmittance of the polymer solutions showed a sharp pH‐dependence around pH 7 as a result of protonation or unprotonation of the imidazole rings, and a high buffering capacity between pH 5.5 and 7. Reversible pH‐dependent aggregation and deaggregation behavior was observed. The mean size of the prepared polymer aggregates with increasing degree of substitution (DS) of API ranged from 180 and 220 nm, while that of the octadecylamine‐conjugated polyaspartamide ones approximately 100 nm. The CAC of MPEG/API‐grafted polyasparamides decreased with increasing DS of API and that of the octadecylamine‐conjugated polyaspartamide aggregates increased with decreasing pH. These pH‐sensitive polyaspartamide derivatives are expected to have many applications in areas, such as an intracellular or tumor targeting drug‐delivery carrier that is triggered by very small changes in pH. © 2008 Wiley Periodicals, Inc. J Biomed Mater Res, 2009
Degradation of magnesium and its alloys: Dependence on the composition of the synthetic biological media
Authors: Mueller Wolf‐Dieter , Fernández Lorenzo de Mele Monica , Nascimento Maria Lucia , Zeddies Miriam 
Published: June 2008

AbstractMagnesium and its alloys are highly degradable metals that are potentially useful as biomaterials, especially in orthopaedic and cardiovascular applications. However, the in vivo corrosion has proved to be too high. Because of the complexity of in vivo conditions, a careful study of the corrosion of magnesium in synthetic solutions that simulate the in vivo environment is necessary as a first approach to predict the actual in vivo situation. The aim of this work was to evaluate the influence of the electrolyte composition on the corrosion behavior of magnesium and two Mg‐alloys in synthetic biological media. Pure magnesium and its alloys (AZ31 and LAE442) were employed in the experiments. Electrochemical potentiodynamic polarization curves were recorded in sodium chloride and PBS electrolytes with different chloride ion and albumin concentration. Optical and SEM observations complemented by EDX analysis were made. The results showed that magnesium corrosion is localized in chloride‐ and albumin‐containing buffer solutions. They also showed that the chloride concentration and the presence of buffer and protein strongly affect the electrochemical behavior of magnesium and magnesium alloys. © 2008 Wiley Periodicals, Inc. J Biomed Mater Res, 2009
Chitosan nano‐/microfibrous double‐layered membrane with rolled‐up three‐dimensional structures for chondrocyte cultivation
Authors: Shim In Kyong , Suh Won Hee , Lee Sang Young , Lee Sang Hoon , Heo Seong Joo , Lee Myung Chul , Lee Seung Jin 
Published: June 2008

AbstractWith an aim to mimic natural extracellular matrix, we fabricated the nano‐ and microfibrous matrix with chitosan by electrospinning nanofibers onto predefined microfibrous mesh for effective chondrocytes cultivation. Rolling the double‐layered nano‐/microfibrous membranes produced three‐dimensional (3‐D) scaffolds that exhibited the interconnected open pore structure in their scanning electron microscopy images. In vitro chondrocyte culture experiment showed that this nano‐/microfibrous 3‐D matrix provided a significantly greater microenvironment for chondrocytes to proliferate and produce glycosaminoglycan as compared with only microfibrous 3‐D matrix. This difference could be explained by the result on 2‐D membrane, where chitosan nanofibrous surface substantially facilitated the cellular attachment and proliferation, and efficiently prevented phenotypic changes of chondrocytes, when compared with chitosan microfibrous membrane and film. In this regard, the nano‐/microfibrous 3‐D matrix we fabricated in this study would possess a great potential as a system for effective chondrocyte cultivation and also for application to cartilage regeneration therapy. © 2008 Wiley Periodicals, Inc. J Biomed Mater Res, 2009
A bioactive triphasic ceramic‐coated hydroxyapatite promotes proliferation and osteogenic differentiation of human bone marrow stromal cells
Authors: Nair Manitha B. , Bernhardt Anne , Lode Anja , Heinemann Christiane , Thieme Sebastian , Hanke Thomas , Varma Harikrishna , Gelinsky Michael , John Annie 
Published: June 2008

AbstractHydroxyapatite (HA) ceramics are widely used as bone graft substitutes because of their biocompatibility and osteoconductivity. However, to enhance the success of therapeutic application, many efforts are undertaken to improve the bioactivity of HA. We have developed a triphasic, silica‐containing ceramic‐coated hydroxyapatite (HASi) and evaluated its performance as a scaffold for cell‐based tissue engineering applications. Human bone marrow stromal cells (hBMSCs) were seeded on both HASi and HA scaffolds and cultured with and without osteogenic supplements for a period of 4 weeks. Cellular responses were determined in vitro in terms of cell adhesion, viability, proliferation, and osteogenic differentiation, where both materials exhibited excellent cytocompatibility. Nevertheless, an enhanced rate of cell proliferation and higher levels of both alkaline phosphatase expression and activity were observed for cells cultured on HASi with osteogenic supplements. These findings indicate that the bioactivity of HA endowed with a silica‐containing coating has definitely influenced the cellular activity, projecting HASi as a suitable candidate material for bone regenerative therapy. © 2008 Wiley Periodicals, Inc. J Biomed Mater Res, 2009
Novel gene‐activated matrix with embedded chitosan/plasmid DNA nanoparticles encoding PDGF for periodontal tissue engineering
Authors: Peng Lin , Cheng Xiangrong , Zhuo Renxi , Lan Jing , Wang Yining , Shi Bin , Li Siqun 
Published: June 2008

AbstractRecently, much attention has been paid to tissue engineering and local gene delivery system in periodontal tissue regeneration. Gene‐activated matrix (GAM) blends these two strategies, serving as a local bioreactor with therapeutic gene expression and providing a structural template to fill the lesion defects for cell adhesion, proliferation and synthesis of extracellular matrix (ECM). In this study, we designed a novel GAM with embedded chitosan/plasmid nanoparticles encoding platelet derived growth factor (PDGF) based on porous chitosan/collagen composite scaffold. The chitosan/collagen scaffold acted as three‐dimensional carrier and chitosan nanoparticles condensed plasmid DNA. The plasmid DNA entrapped in the scaffolds showed a sustained and steady release over 6 weeks and could be effectively protected by chitosan nanoparticles. MTT assay demonstrated that periodontal ligament cells (PDLCs) cultured into the novel GAM achieved high proliferation. Luciferase reporter gene assay displayed that the novel GAM could express 1.07×104 LU/mg protein after 1 week and 8.97×103 LU/mg protein after 2 weeks. The histological results confirmed that PDLCs maintained a fibroblast figure and the periodontal connective tissue‐like structure formed in the scaffolds after 2 weeks. Semi‐quantitative immunohistochemical results suggested that PDGF protein expressed at a relatively high level after 2 weeks. From this study, it can be concluded that the novel GAM had potential in the application of periodontal tissue engineering. © 2008 Wiley Periodicals, Inc. J Biomed Mater Res, 2009
UHMWPE carrying estradiol to treat the particle‐induced osteolysis—Processing and characterizing
Authors: Liu Aiqin , Qu Shuxin , Chao Mengmeng , Zhu Minhao , Weng Jie , Zhou Zhongrong 
Published: June 2008

AbstractThe objective of this study was to explore the possibility of UHMWPE implant used as the drug carrier to treat particle‐induced osteolysis. 17β‐estradiol (E2), which had the potential application on osteolysis treatment and the high melting point, was added into UHMWPE powder to produce UHMWPE‐E2 composites through hot press processing. The hydrophobicity, crystallinity, mechanical properties, and wear performance of the UHMWPE‐E2 were characterized compared with the control UHMWPE. The thermal analysis and Fourier Transform Infrared Spectroscopy results demonstrated that the hot press processing would not alter the functional groups of E2 in this study. There were no significant differences in the hydrophobicity and crystallinity between the UHMWPE‐E2 and UHMWPE. The UHMWPE‐E2 showed satisfying mechanical properties, including ultimate tensile strength (47.2 ± 3.6 MPa), yield strength (25.0 ± 0.6 MPa) and elongation at break (320 ± 25.5 %), which were similar with the control UHMWPE. The friction coefficients and worn scars were similar between the UHMWPE‐E2 and the control UHMWPE. The wear mechanism of the UHMWPE‐E2 and UHMWPE both were abrasive wear under dry friction. The UHMWPE‐E2 possesses the approving mechanical properties and wear performance compared with the control UHMWPE, which might be used as the potential implanted drug carrier to prevent the particle‐induced osteolysis in joint replacements. © 2008 Wiley Periodicals, Inc. J Biomed Mater Res, 2009
Trace concentrations of vitamin E protect radiation crosslinked UHMWPE from oxidative degradation
Authors: Kurtz S. M. , Dumbleton J. , Siskey R. S. , Wang A. , Manley M. 
Published: June 2008

AbstractThe effect of very low concentrations of Vitamin E on the stability and mechanical behavior of UHMWPE remains unknown. We tested the hypothesis that the oxidation resistance of Vitamin E‐blended UHMWPE would be influenced by trace doses of antioxidant, resin, and radiation treatment. Trace concentrations (≤500 ppm w/w%) of α‐tocopherol (Vitamin E) were blended separately with GUR 1020 and 1050 resins and molded into disks. From each disk, three groups of 10 mm thick blocks were machined: (1) no irradiation (control); (2) 30 kGy of gamma irradiation in nitrogen; and (3) 75 kGy of gamma irradiation in air. Specimens were subjected to three aging protocols: (a) no aging (control); (b) two weeks and (c) four weeks of accelerated aging in accordance with ASTM F 2003 (i.e., 70°C and 5 atm oxygen). The minimum concentration of Vitamin E needed to stabilize UHMWPE during our accelerated tests depended upon the method of radiation processing. For the 30 and 75 kGy irradiated materials, the addition of 125 ppm or more Vitamin E was sufficient to maintain baseline mechanical and chemical properties through two weeks of accelerated aging. For these groups, the addition of 375 ppm or 500 ppm, respectively, was necessary to maintain baseline mechanical and chemical properties throughout the four‐week accelerated aging period. UHMWPE resin molecular weight did not have an effect on oxidation behavior. The results of this experiment therefore supported our hypotheses that trace concentrations of Vitamin E, coupled with radiation treatment—but not resin grade—influence the mechanical and oxidative degradation behavior of UHMWPE. © 2008 Wiley Periodicals, Inc. J Biomed Mater Res 90A: 549–563, 2008
Repair of long intercalated rib defects in dogs using recombinant human bone morphogenetic protein‐2 delivered by a synthetic polymer and beta‐tricalcium phosphate
Authors: Hoshino Masatoshi , Egi Takeshi , Terai Hidetomi , Namikawa Takashi , Kato Minori , Hashimoto Yusuke , Takaoka Kunio 
Published: June 2008

AbstractLong intercalated defects in canine ribs can be repaired successfully using porous beta‐tricalcium phosphate (β‐TCP) cylinders, infused with a biodegradable polymer (poly D,L‐lactic acid‐polyethylene block copolymer) containing recombinant human bone morphogenetic protein‐2 (rhBMP‐2). We previously reported the successful regeneration of bony rib and periosteum defects using β‐TCP cylinders containing 400 μg of rhBMP‐2. To reduce the amount of rhBMP‐2 and decrease the time required for defect repair, we utilized a biodegradable polymer carrier, in combination with rhBMP‐2 and the porous β‐TCP cylinders. An 8 cm long section of rib bone was removed and replaced with an implant comprised of the porous β‐TCP cylinders and the polymer containing 80 μg of rhBMP‐2. Six weeks after surgical placement of the β‐TCP cylinder/polymer/BMP‐2 implants, new rib bone with an anatomical configuration and mechanical strength similar to the original bone was regenerated at the defect site. The stiffness of the regenerated ribs at 3, 6, and 12 weeks after implantation of the composite implant was significantly higher than that of ribs regenerated by implantation of rhBMP‐2/β‐TCP implants. Thus, addition of the synthetic polymer to the drug delivery system for BMP potentiated the bone‐regenerating ability of the implant and enabled the formation of mechanically competent rib bone. This new method appears to be applicable to the repair of intercalated long bone defects often encountered in clinical practice. © 2008 Wiley Periodicals, Inc. J Biomed Mater Res, 2009
Matrix therapy in regenerative medicine, a new approach to chronic wound healing
Authors: Barbier‐Chassefière V. , Garcia‐Filipe S. , Yue X. L. , Kerros M. E. , Petit E. , Kern P. , Saffar J. L. , Papy‐Garcia D. , Caruelle J. P. , Barritault D. 
Published: June 2008

AbstractNonhealing wounds remain a major health problem whose treatment is challenging and costly. Treatments based on cells or growth factors are still not very effective. We developed an entirely novel strategy consisting in treatment of the wound‐tissue matrix with biopolymers engineered to mimic heparan sulfates called OTR4120. This compound was dextran polymer with sulfated and carboxymethyl groupments. After binding to matrix proteins, the heparan‐sulfate‐mimicking polymer protects the microenvironment, maintaining the normal production of signals and growth factors needed for healing to occur. Here, we show that a specific biopolymer accelerates ulcer closure and improves re‐epithelialization and dermal‐matrix‐component remodeling. OTR4120 treatment was associated with faster maturation of epidermal structures, most notably regarding the number of epithelial‐cell layers, and with an appearance that more closely resembled normal skin. Treatment had also a main effect on collagen I and III expression. Necrotic skin ulcers induced in mice with doxorubicin recovered normal collagen levels and organization, with no evidence of fibrosis. Thus, appropriate polymer‐based matrix therapy is a valid and simple alternative to regenerative medicine. © 2008 Wiley Periodicals, Inc. J Biomed Mater Res, 2009
Assessment of the biocompatibility of photosensitive polyimide for implantable medical device use
Authors: Sun Y. , Lacour S. P. , Brooks R. A. , Rushton N. , Fawcett J. , Cameron R. E. 
Published: June 2008

AbstractPolyimides have been widely used for biosensor encapsulation and more recently as substrates for neural implants. They have excellent thermal stability, high chemical resistance, and can be prepared as thin, flexible films. Photosensitive polyimides present similar physical properties to polyimides, and have the advantage that they can be photo‐lithographically patterned. However, to date little data on their biocompatibility has been reported. Two commercially available polyimides (PI) and one photo‐sensitive polyimide (PSPI) were evaluated in vitro using the ISO 10993 standard on biocompatibility. The materials were Dupont Kapton foil HN, HD Microsystem PI2611, and Fujifilm Durimide 7020 (PSPI). PI2611 and Durimide 7020 were spin‐coated on silicon wafers, cured at temperatures ranging from 150 to 450°C, and sterilized by autoclave. All materials were evaluated using a scanning electron microscope pre‐ and postcell culture. Cell viability was determined by an MTS assay. Their mechanical properties and stability during cell culture as a function of time and environment were investigated by nanoindentation. The MTS results show that PSPI is noncytotoxic compared with the negative control of polyethylene and the conventional PIs tested. Fibroblast adhesion, morphology, and spreading were good and better on the PSPI substrate than on the PI2611. Schwann cell appearance was similar on each of the PIs and the PSPI tested. The results suggest that PSPIs may have potential use for biological microsystem and neuroprosthetic applications. © 2008 Wiley Periodicals, Inc. J Biomed Mater Res, 2009
Elastic and macroporous agarose–gelatin cryogels with isotropic and anisotropic porosity for tissue engineering
Authors: Tripathi Anuj , Kathuria Neeraj , Kumar Ashok 
Published: June 2008

AbstractThe focus of this work was to design a macroporous scaffold with controlled porosity in isotropic and anisotropic manner for tissue‐engineering applications. Agarose–gelatin scaffolds were synthesized by cryogelation method, in which agarose was used to improve the mechanical characteristics and gelatin‐provided amiable property of elasticity, cell adhesion, and cell proliferation in the scaffold. Agarose–gelatin (8%) cryogels synthesized in two different solvent systems (i.e., water and 0.1% acetic acid) at subzero temperature (−12°C) showed well‐interconnected porous structure. The agarose–gelatin cryogel synthesized in water solvent system (WSS) showed gradient porosity with an average pore diameter of a monolith (four sections from bottom to top; height 5 mm and diameter 13 mm each) ranging from 76 to 187 μm. The monolith of agarose–gelatin synthesized in 0.1% acetic acid solvent system (0.1% ASS) did not show any remarkable difference in average pore diameter of a monolith to their whole column length as revealed by scanning electron microscopy (SEM). These cryogels swelled up to ∼90% of their capacity within 1 min. The aggregate tensile modulus showed good elasticity of the cryogels, in which agarose–gelatin synthesized in WSS showed higher tensile modulus, that is, 380.23 ± 63.97 kPa in comparison with agarose–gelatin synthesized in 0.1% ASS, i.e., 278.08 ± 94.08 kPa. The unconfined fatigue observation with varying strain (10–40%) and varying frequencies (2 and 5 Hz) showed no deformation of cryogels. The fibroblast (Cos‐7) cell line seeded on the scaffold displayed good cell attachment in both types of cryogels and MTT assay showed good cell compatibility and favorable conditions for cell proliferation. These results indicate that agarose–gelatin cryogels can be a promising material of choice for tissue‐engineering applications. © 2008 Wiley Periodicals, Inc. J Biomed Mater Res, 2009
Proliferation and differentiation of osteoblast‐like MC3T3‐E1 cells on biomimetically and electrolytically deposited calcium phosphate coatings
Authors: Wang Jiawei , de Boer Jan , de Groot Klaas 
Published: June 2008

AbstractBiomimetic and electrolytic deposition are versatile methods to prepare calcium phosphate coatings. In this article, we compared the effects of biomimetically deposited octacalcium phosphate and carbonate apatite coatings as well as electrolytically deposited carbonate apatite coating on the proliferation and differentiation of mouse osteoblast‐like MC3T3‐E1 cells. It was found that MC3T3‐E1 cells cultured on the biomimetically deposited carbonate apatite coating demonstrated the greatest proliferation rate and the highest differentiation potential. Cells on the biomimetically deposited octacalcium phosphate coating had lower proliferation rate before day 7, but higher after that, than those on the electrolytically deposited carbonate apatite coating. There was no difference on the expression of early differentiation markers, that is, alkaline phosphatase activity and collagen content, between biomimetically deposited octacalcium phosphate and electrolytically deposited carbonate apatite coatings. However, higher expression of late differentiation markers, that is, osteocalcin and bone sialoprotein mRNA, was found on the biomimetically deposited octacalcium phosphate coating on day 14. These results suggest that the difference in in vitro osteoblast cell performance of calcium phosphate coatings might relate to their physicochemical properties. Biomimetic carbonate apatite coating is the most favorable surface for the proliferation and differentiation of MC3T3‐E1 cells. © 2008 Wiley Periodicals, Inc. J Biomed Mater Res, 2009