bluuebunny/crossref_metadata_2025_split huggingface dataset:
Combining keratinocyte growth factor transfection into the airways and tracheal occlusion in a fetal sheep model of congenital diaphragmatic hernia
Authors: Saada Julien , Oudrhiri Noufissa , Bonnard Arnaud , de Lagausie Pascal , Aissaoui Abderrahim , Hauchecorne Michelle , Oury Jean‐François , Aigrain Yves , Peuchmaur Michel , Lehn Jean‐Marie , Lehn Pierre , Luton Dominique 
Published: March 2010

AbstractBackgroundIn utero tracheal occlusion (TO) has been developed to improve the lung hypoplasia associated with congenital diaphragmatic hernia (CDH). However, although TO stimulates fetal lung growth, it results in a decrease of alveolar type II cells (ATII) and surfactant production. Because keratinocyte growth factor (KGF) is a potent stimulus of ATII proliferation and maturation, we evaluated, in a fetal lamb model of CDH, a gene therapy strategy combining TO and ovine KGF transfection into the fetal airways using bisguanidinium‐tren‐cholesterol/dioleoyl‐phosphatidylethanolamine (BGTC/DOPE) cationic liposomes.MethodsThree groups of sheep fetuses with CDH and a group of normal fetuses were studied. The fetuses of the three groups with CDH (KGF, Medium and Hernia groups) underwent surgery at 85 days of gestation to create a diaphragmatic hernia. The KGF and medium group fetuses underwent a second surgery step at day 125 to perform TO associated with injection of the KGF transfection mixture (KGF group) or control medium (Medium group), whereas the fetuses of the Hernia group were left untreated. Normal fetuses were used as a control (Normal group). All fetuses were euthanized at 132 days of gestation and various analytical studies [lung weight, radial alveolar count (RAC), KGF and surfactant protein B (SPB) expression, number of ATII cells] were performed to assess the efficiency of KGF transfection and its effects on fetal lung development.ResultsTO was associated with lung hyperplasia and increased RAC in the Medium and KGF groups versus the Hernia group. Expression of KGF was increased in the KGF group compared to all other groups and was associated with an increased synthesis of SPB by alveolar cells and an ectopic synthesis of SPB by bronchiolar cells compared to TO treatment alone.ConclusionsThus, BGTC/DOPE liposomes can mediate efficient KGF transfection into the airways in a fetal sheep model of CDH. Furthermore, combining KGF transfection and TO resulted not only (as did TO alone) in the correction of the CDH‐associated lung hypoplasia and decreased RAC, but also in increased SPB synthesis, suggesting a better maturation of the re‐growing lung (compared to TO alone). Additional studies are required to further explore the therapeutic potential of such a combined strategy; in particular, studies evaluating the lung function of in utero‐treated CDH lamb newborns. Copyright © 2010 John Wiley & Sons, Ltd.
Differential antitumor effect of interleukin‐12 family cytokines on orthotopic hepatocellular carcinoma
Authors: Lo Chia‐Hui , Chang Chia‐Ming , Tang Shih‐Wen , Pan Wen‐Yu , Fang Cheng‐Chieh , Chen Yin , Wu Ping‐Yi , Chen Kai‐Yun , Ma Hsin‐I , Xiao Xiao , Tao Mi‐Hua 
Published: March 2010

AbstractBackgroundHepatocellular carcinoma (HCC) is one of the most difficult cancers to treat. The interleukin (IL)‐12 family cytokines, including IL‐12, IL‐23 and IL‐27, display overlapping, but not redundant, roles in regulating lymphocyte subpopulations. IL‐12 is known as a potent antitumor cytokine, whereas the results of the antitumor effect of IL‐23 and IL‐27 are inconsistent. The present study aimed to directly compare the relative antitumor efficacy of these three IL‐12 family cytokines on HCC.MethodsA murine orthotopic BNL HCC model, in which the tumor is located in an environment heavily populated with different lymphocyte subsets, was established. The hepatotropic adeno‐associated virus serotype 8 (AAV8) vector was used to deliver the cytokine genes aiming to achieve sustained cytokine expression in the liver.ResultsAAV8/IL‐12 treatment significantly reduced hepatic metastases and prolonged survival time, whereas treatment with AAV8/IL‐23 or AAV8/IL‐27 had only moderate antitumor effects at a high dose. The antitumor efficacy of these cytokines was positively correlated with their ability to regulate hepatic T cells, natural killer cells and natural killer T cells, with IL‐12 greatly increasing the number and activation status of these cells, whereas IL‐27 had no effect and IL‐23 had a negative effect. AAV8/IL‐12 treatment also resulted in a marked decrease in tumor vessel density, which was not observed with AAV8/IL‐23 and AAV8/IL‐27 treatment.ConclusionsThe data obtained in the present study highlight the importance of local lymphocytes and anti‐angiogenesis for influencing the antitumor activity of these three IL‐12 family cytokines and suggest that IL‐12 is the best candidate for treating HCC. Copyright © 2010 John Wiley & Sons, Ltd.
Agricultural innovation and food security in Sub‐Saharan Africa: Tracing connections and missing links
Authors: Mugwagwa Julius T. , Wamae Watu , Outram Simon M. 
Published: March 2010

AbstractGrounded in research carried out by researchers investigating different aspects of technological and institutional innovation in agriculture in Sub‐Saharan Africa (SSA), this special issue seeks to make a contribution to empirical evidence and literature on agricultural innovation globally. The contributors explore the relationship between technology, policy and public engagement approaches and wider concepts of technology development and governance, and collectively argue for a broadened perspective on innovation towards generating new ways of thinking that can ultimately improve upon existing practices in the quest for sustainable solutions to food insecurity. Overall, this is not a negative story. Instead of the now common despair about the abilities of Africa to meet it is own food‐security requirements, this issue presents articles which demonstrate how much is already in place, with reflections and suggestions on how such resources can be made to work together for the greater socio‐economic good of the continent Copyright © 2010 John Wiley & Sons, Ltd.
What do complex adaptive systems look like and what are the implications for innovation policy?
Authors: Hall Andy , Clark Norman 
Published: March 2010

AbstractThis paper explores the use of complex adaptive systems theory in development policy analysis using a case study drawn from recent events in Uganda. It documents the changes that took place in the farming system in Soroti district during an outbreak of African cassava mosaic virus disease (ACMVD) and the subsequent decline in cassava production—the main staple food in the area. Resultant adaptation impacts are analysed across cropping, biological, economic and social systems each of which operate as an interlinked sub‐systems. The policy implications of this story suggest a policy agenda that recognises adaptation capacity as the life blood of complex adaptive systems. Since these types of system are found in all realms of human activity, it follows that strengthening this capacity is a key developmental priority that requires linking together new configurations of actors and resources to tackle an ever changing set of contexts. Copyright © 2010 John Wiley & Sons, Ltd.
Radiosynthesis and in vivo evaluation of a F‐18‐labeled pancreatic islet amyloid inhibitor
Authors: Pathuri Gopal , Agashe Hrushikesh B. , Awasthi Vibhudutta , Gali Hariprasad 
Published: March 2010

AbstractFormation of islet amyloid deposits contributes to the progressive loss of beta‐cells in Type 2 diabetes. Islet amyloid is composed of islet amyloid polypeptide (IAPP). [(N‐Me)G24, (N‐Me)I26]hIAPP(22–27) peptide was found to bind human IAPP with high‐affinity and inhibit fibrillogenesis. We labeled [(N‐Me)G24, (N‐Me)I26]hIAPP(22–27) with fluorine‐18 using N‐succinimidyl‐4‐[18F]fluorobenzoate. Results from biodistribution studies in healthy CF‐1 mice at 1 h p.i. indicated that 18F‐peptide was cleared efficiently (0.04±0.02%ID/g remained in blood). The primary route of clearance from the body appears to be hepatobiliary. Radioactivity accumulation in liver, intestine, and kidney was 6.7±2.9, 60.3±18.5, and 0.2±0.0%ID, respectively. Other organs accumulated negligible radioactivity. As normal mice do not develop pancreatic amyloid deposits, only background radioactivity was seen in pancreas. The radio‐HPLC analysis of mouse urine at 2 h p.i. showed that ∼29.3% of injected 18F‐peptide excreted intact along with two additional metabolite peaks. Dynamic microPET/CT imaging of a CF‐1 mouse injected with 18F‐peptide indicated that radiotracer was rapidly taken up by liver and most of it moved into intestine within 10 min. The results provide a useful insight into the biological disposition of [(N‐Me)G24, (N‐Me)I26]hIAPP(22–27) that is being developed as a pancreatic amyloid inhibitor. Copyright © 2010 John Wiley & Sons, Ltd.
Surface‐enhanced Raman spectroscopy for trace‐level detection of explosives
Authors: Botti S. , Cantarini L. , Palucci A. 
Published: March 2010

AbstractThe detection of explosives and their associated compounds for security screening is an active area of research and a wide variety of detection methods are involved in this very challenging area. Surface‐enhanced Raman scattering (SERS) spectroscopy is one of the most sensitive tools for the detection of molecules adsorbed on nano‐scale roughened metal surface. Moreover, SERS combines high sensitivity with the observation of vibrational spectra of species, giving complete information on the molecular structure of material under study. In this paper, SERS was applied to the detection of very small quantities of explosives adsorbed on industrially made substrates. The spectra were acquired with a compact Raman spectrometer. Usually, a high signal‐to‐noise (S/N) spectrum, suitable for identification of explosive molecules down to few hundreds of picograms, was achieved within 30 s. Our measurements suggest that it is possible to exploit SERS using a practical detection instrument for routine analysis. Copyright © 2010 John Wiley & Sons, Ltd.
Kinetic investigation of aquation of some Fe(II) Schiff base amino acid complexes
Authors: Nassr Lobna Abdel‐Mohsen Ebaid 
Published: March 2010

AbstractKinetics of aquation of some Fe(II) Schiff base amino acid complexes was followed spectrophotometrically. The Schiff base ligands were derived from salicylaldehyde and isoleucine, leucine, serine, methionine, tryptophan, or histidine. The reaction was studied in aqueous media, aqua–propanol mixtures, and in the presence of different concentrations of KBr. Moreover, the activation parameters were calculated and discussed for structures and other physical properties observed. The reaction was acid catalyzed and the general rate equation was suggested as follows: rate = kobs [complex], where kobs = k2 [H+]. © 2010 Wiley Periodicals, Inc. Int J Chem Kinet 42: 372–379, 2010
Regulation of the G2/M transition in rodent oocytes
Authors: Downs Stephen M. 
Published: March 2010

AbstractRegulation of maturation in meiotically competent mammalian oocytes is a complex process involving the carefully coordinated exchange of signals between the somatic and germ cell compartments of the ovarian follicle via paracrine and cell–cell coupling pathways. This review highlights recent advances in our understanding of how such signaling controls both meiotic arrest and gonadotropin‐triggered meiotic resumption in competent oocytes and relates them to the historical context. Emphasis will be on rodent systems, where many of these new findings have taken place. A regulatory scheme is then proposed that integrates this information into an overall framework for meiotic regulation that demonstrates the complex interplay between different follicular compartments. Mol. Reprod. Dev. 77: 566–585, 2010. © 2010 Wiley‐Liss, Inc.
Molecular cloning and expression analysis of Fshr and Lhr in relation to Fshb and Lhb subunits during the period of temperature‐dependent sex determination in pejerrey Odontesthes bonariensis
Authors: Shinoda Takahiro , Miranda Leandro A. , Okuma Kozue , Hattori Ricardo S. , Fernandino Juan I. , Yoshizaki Goro , Somoza Gustavo M. , Strüssmann Carlos A. 
Published: March 2010

AbstractIn this study, we cloned and characterized the follicle stimulating hormone receptor (Fshr) and luteinizing hormone receptor (Lhr) cDNAs of pejerrey Odontesthes bonariensis, a species with temperature‐dependent sex determination (TSD), and analyzed their expression in relation to Fshb and Lhb subunits during gonadogenesis at temperatures producing only females (17°C, FPT), both sexes (25°C, MixPT), and only males (29°C, MPT). The pejerrey Fshr cDNA had 3,069 bp for a mature protein of 694 amino acids (aa) and a signal peptide of 22 aa; the Lhr cDNA had 2,936 bp for a mature protein of 676 aa and a signal peptide of 25 aa. With the exception of Lhr in fish at the MPT, all genes showed significant increases and/or peaks of expression before histological differentiation of the gonads regardless of temperature. Larvae at the FPT had lower Fshb and Lhb but higher Lhr expression during the TSD period than those at the MPT; a clear pattern could not be ascertained for Fshr. At the MixPT, Fshb, Lhb, and Lhr mRNA increased in approximately half of the fish during TSD and sex differentiation and the sex ratio was 55.2% male. Based on the above results, it is suggested that animals with high Fshb and Lhb and low Lhr values represent putative males. These evidences, together with other studies, suggest that temperature may signal through the pituitary (differential expression of Fshb and Lhb) down to the gonads (differential expression of Lhr), probably affecting the regulation of steroidogenesis during the TSD process of pejerrey. Mol. Reprod. Dev. 77: 521–532, 2010. © 2010 Wiley‐Liss, Inc.
Constitutive modeling of rubberlike materials based on consistent strain energy density functions
Authors: Darijani H. , Naghdabadi R. , Kargarnovin M.H. 
Published: March 2010

AbstractRubberlike materials are characterized by high deformability and reversibility of deformation. From the continuum viewpoint, a strain energy density function is postulated for modeling the behavior of these materials. In this paper, a general form for the strain energy density of these materials is proposed from a phenomenological point of view. Based on the Valanis‐Landel hypothesis, the strain energy density of incompressible materials is expressed as the sum of independent functions of the principal stretches meeting the essential requirements on the form of the strain energy density. It is cleared that the appropriate mathematical expressions for constitutive modeling of these materials are polynomial, logarithmic, and particularly exponential functions. In addition, the material parameters are calculated using a novel procedure that is based on the correlation between the values of the strain energy density (rather than the stresses) cast from the test data and the theory. In order to evaluate the performance of the proposed strain energy density functions, some test data of rubberlike materials with pure homogeneous deformations are used. It is shown that there is a good agreement between the test data and predictions of the models for incompressible isotropic materials. POLYM. ENG. SCI., 2010. © 2010 Society of Plastics Engineers
Rotational molding of polycarbonate reinforced polyethylene composites: Processing parameters and properties
Authors: Liu Shih‐Jung , Peng Kang‐Ming 
Published: March 2010

AbstractRotational molding has become one of the most important polymer processing methods for producing hollow plastic articles. The goal of this report is to study the rotational molding of polycarbonate (PC) reinforced polyethylene composites. Experiments were carried out on a laboratory scale uniaxial machine, which is capable of measuring internal air temperatures in the cycle. Before molding, PC and polyethylene were blended by a twin‐screw extruder. The extrudate was cut into pellets. Polyethylene powder mixed with PC/polyethylene pellets were then mixed by a dry mixer and rotationally molded by a box mold. Characterization of molded part properties was performed after molding. It was found that the impact strength of molded composites increased with the volume fraction of PC reinforcement, whereas the tensile strengths decreased with the reinforcement. Higher cooling rates molded composites with higher impact strengths but lower tensile strengths. There exists an optimum internal peak air temperature with which composites of the highest mechanical properties can be obtained. Additionally, various mathematical models were employed to predict the tensile properties of molded composites, and the Halpin–Tsai–Nielsen model was found to match well with the measured tensile modulus of molded composites. POLYM. ENG. SCI., 2010. © 2010 Society of Plastics Engineers
Process of grafting styrene onto LLDPE by swelling and suspension copolymerization
Authors: Yan Jing , Miao Xiaojie , Cui Xuejun , Jin Weiqun , Liang Hongwei , Li Junfeng , Wang Hongyan 
Published: March 2010

AbstractA technology of swelling and suspension copolymerization was conducted to graft styrene onto linear low‐density polyethylene (LLDPE). The graft mechanism of styrene with LLDPE had been described by 1H NMR and IR. The mean particle diameter and size distribution of the products with different proportions of LLDPE to styrene monomer were calculated. The morphology and thermal behavior of copolymers were characterized by scanning electron microscopy and differential scanning calorimetry. The glass transition temperature of copolymers increased with the addition of LLDPE, which proved the existence of the polyethylene‐g‐polystyrene copolymer. The grafting efficiency and granulation rate of suspension copolymerization were investigated. It was found that the grafting efficiency increased and the granulation rate decreased with the addition of LLDPE. POLYM. ENG. SCI., 50:1713–1720, 2010. © 2010 Society of Plastics Engineers
Crystallization and biodegradation of polylactide/carbon nanotube composites
Authors: Wu Defeng , Wu Liang , Zhou Weidong , Zhang Ming , Yang Tao 
Published: March 2010

AbstractThe crystallization behavior of polylactide/carbon nanotube composites was studied using differential scanning calorimeter and polarized optical microscope. The nucleation mechanisms and the crystallization kinetics were explored. The results show that the presence of nanotubes has nucleating effect on both the melt crystallization and the cold crystallization of PLA. However, the nanotubes also play the role of physical barrier, impeding the crystal growth dynamically. In the experimental range of temperatures, the presence of nanotubes accelerates the melt crystallization, while retards the overall kinetics of the cold crystallization. The biodegradability of the samples with various crystallization histories was then further examined. The results show that the presence of nanotubes reduces the biodegradation rate of PLA, and the amorphous sample shows the highest degradation levels. Moreover, a lower degradation level is observed both on the surface and inside the sample with melt crystallization history in contrast to the one with cold crystallization history. POLYM. ENG. SCI., 50:1721–1733, 2010. © 2010 Society of Plastics Engineers
Poly(acrylonitrile‐co‐vinyl acetate)/Ag composite microspheres: One‐pot fabrication and application as catalyst
Authors: Xiao Hongping , Xia Youyi 
Published: March 2010

AbstractWaxberry‐like poly(acrylonitrile‐co‐vinyl acetate)/Ag composite microspheres have been prepared simply and directly via a one‐step self‐assembly approach. The morphology, formation, and catalytic activity of the as‐prepared composite microspheres are further investigated. The difference in the solubility among different segments of poly(acrylonitrile‐co‐vinyl acetate) is the basis of the formation of poly(acrylonitrile‐co‐vinyl acetate) microspheres, while the CN groups on the surface of poly(acrylonitrile‐co‐vinyl acetate) microspheres play an important role in the growth process from poly(acrylonitrile‐co‐vinyl acetate) microsphere to poly(acrylonitrile‐co‐vinyl acetate)/Ag composite microsphere. It is found that bulk quantities of composite microspheres with high density of Ag nanoparticles on the surface can be obtained readily by controlling the concentration of AgNO3. The as‐prepared composite microsphere exhibits excellent catalytic activity on reduction of p‐nitrophenol. This study may shed some light on the self‐assembly of other metal/polymer composite microspheres. POLYM. ENG. SCI., 50:1767–1772, 2010. © 2010 Society of Plastics Engineers
A theoretical model of concurrent longitudinal and circumferential superdrawing of hollow polyethylene terephthalate fibers
Authors: Wang Youjiang , Aneja Arun Pal 
Published: March 2010

AbstractIn a superdrawing process, a polyethylene terephthalate (PET) filament is elongated without developing much orientation and crystallization. Exploiting this phenomenon may bring about lower cost, more flexible and faster response in synthetic fiber production. The concurrent longitudinal and circumferential superdrawing phenomenon of PET hollow fibers is explained using the viscoelastic behavior of a thick walled cylinder under an internal pressure and an axial load in a continuous process. The model defines the stress–strain‐displacement relationship of hollow fibers. The fiber undergoes instantaneous radial superdrawing (increase in thickness) in the process zone followed by concurrent circumferential (increase in void) and longitudinal (increase in length) superdrawing. Based on material viscoelastic properties and processing conditions, the model predicts the threadline tension, internal pressure, and final fiber geometries. Excellent agreement of the model with experimental results is observed over a range of processing conditions. The model is developed from a process engineering viewpoint to enable the analysis of the impact of process parameters during superdrawing on fiber properties. POLYM. ENG. SCI., 50:1773–1779, 2010. © 2010 Society of Plastics Engineers
Thermomechanical properties of virgin and recycled polypropylene impact copolymer/CaCO3 nanocomposites
Authors: Elloumi A. , Pimbert S. , Bourmaud A. , Bradai C. 
Published: March 2010

AbstractThe effect of successive injection moldings on the thermal, rheological, and mechanical properties of a polypropylene impact copolymer (PP) was investigated. The crystal content decreased as the molecular weight decreased due to chain scission with repeated injection molding. The Young modulus and the yield stress remained constant, despite a drop in the strain to break. Virgin and recycled PP matrix were filled with nanosized calcium carbonate (CaCO3) particles. The effect of morphology on the thermal and mechanical properties of nanocomposites of virgin and recycled PP filled with nanosized CaCO3 particles was also studied. The mechanical properties of the nanocomposites were strongly influenced by the intrinsic toughness of the matrix and the concentration and dispersion of the filler. The yield strength and strain of virgin PP decreased gradually, while its Young's modulus increased slightly with increasing CaCO3 loading. These phenomena were less pronounced for the recycled matrix. Incorporation of nanoparticles to virgin matrix produced an increase in tensile stiffness and ductility, when good dispersion of the filler was achieved. However, the impact strength dropped dramatically for high filler contents. A significant increase in impact strength was observed for the recycled PP. POLYM. ENG. SCI., 50:1904–1913, 2010. © 2010 Society of Plastics Engineers