bluuebunny/crossref_metadata_2025_split huggingface dataset:
Synthesis of the lipid peroxidation product 4‐hydroxy‐2(E)‐nonenal with 13C stable isotope incorporation
Authors: Jouanin I. , Sreevani V. , Rathahao E. , Guéraud F. , Paris A. 
Published: January 2008

AbstractThe aim of this work was to synthesize 13C internal standards for the quantification of 4‐hydroxy‐2(E)‐nonenal (HNE), a lipid peroxidation product, and of the etheno‐adducts possibly formed by HNE damage to DNA nucleobases. We designed an eight‐step synthesis starting from ethyl 2‐bromoacetate and giving access to 4‐[(tetrahydro‐2H‐pyran‐2‐yl)oxy]‐2(E)‐nonenal. This compound is a precursor of HNE. The scheme was then used to produce the 13C precursor [1,2‐13C2]‐4‐[(tetrahydro‐2H‐pyran‐2‐yl)oxy]‐2(E)‐nonenal. [1,2‐13C2]‐HNE was obtained by acid deprotection. All the intermediary and final compounds were fully characterized by IR, HRMS, 1H and 13C NMR. It is the first synthesis of HNE which enables the incorporation of two 13C labels at determined positions. Copyright © 2008 John Wiley & Sons, Ltd.
Synthesis of deuterium‐labelled 5′‐O‐[N‐(Salicyl)sulfamoyl]adenosine (Sal‐AMS‐d4) as an internal standard for quantitation of Sal‐AMS
Authors: Gupte Amol , Subramanian Murali , Remmel Rory P. , Aldrich Courtney C. 
Published: January 2008

Abstract5′‐O‐[N‐(Salicyl)sulfamoyl]adenosine (Sal‐AMS, 1) is a potent inhibitor of the bifunctional enzyme salicyl‐AMP ligase in Mycobacterium tuberculosis. This inhibitor acts by disrupting the biosynthesis of the mycobactin siderophores that are essential for the process of iron acquisition. To aid with in vitro metabolism and in vivo pharmacokinetic studies of Sal‐AMS, a stable deuterium‐labelled Sal‐AMS analog (Sal‐AMS‐d4) was synthesized. This deuterium‐labelled analog was used as an internal standard to conduct in vitro plasma and microsomal stability studies. Sal‐AMS was found to be stable for 24 h in human plasma and 1 h in human liver microsomes at 37°C. Copyright © 2008 John Wiley & Sons, Ltd.
Laser induced collagen remodeling: A comparative study in vivo on mouse model
Authors: Liu Huaxu , Dang Yongyan , Wang Zhan , Chai Xinyu , Ren Qiushi 
Published: January 2008

AbstractBackground and ObjectiveMany lasers have claimed the clinical efficacy on skin rejuvenation. In this study, the mechanisms of laser induced collagen remodeling were explored systematically on a Kunming (KM) mouse model in vivo by comparing the different non‐ablative laser effects using four different laser treatment modalities.Materials and MethodsThe dorsal skin of KM mice was exposed by depilation before the laser treatments. Four laser treatment modalities were used: the 595‐nm pulsed dye laser (PDL) (10 ms), 1,320‐nm neodymium–yttrium–aluminum garnet (Nd:YAG) laser (0.35 ms), 1,064‐nm Nd:YAG laser with Q‐switched (5 ns), and long‐pulsed (0.3 ms) mode. Each modality exposed one side of the mouse dorsal skin leaving the other side as the contralateral control. Then skin histology, fibroblast number, and the genesis of collagen type I and III were studied by comparing the treatment site and control site at 1 hour, 1 day, 1 week, 3 weeks, 4 weeks, and 8 weeks after laser treatment. Hydroxyproline content of the skin tissue was measured 4 weeks and 8 weeks after laser exposure.ResultsAll laser treatments led to marked improvements in dermal layer thickness and collagen fiber density, and the increase in fibroblast number and hydroxyproline content compared with their own controls. Collagen synthesis and remodeling induced by the Q‐switched 1,064‐nm laser was most effective 4 weeks after treatment, while there was no significant difference among the other three modalities. Among the new collagen genesis after the different laser treatments, collagen type III increased sharply after the Q‐switched 1,064‐nm laser treatment whereas more collagen type I was elicited by the other laser treatment modalities.ConclusionsThe efficacy of photo‐mechanical effects in promoting more effectively the synthesis of collagen type III, whereas the photo‐thermal effect favored more the formation of collagen type I. Lesers Surg. Med. 40:13–19, 2008. © 2008 Wiley‐Liss, Inc.
Primary myogenic cells see the light: Improved survival of transplanted myogenic cells following low energy laser irradiation
Authors: Shefer Gabi , Ben‐Dov Nadav , Halevy Orna , Oron Uri 
Published: January 2008

AbstractBackground and ObjectivesThere is a substantial need for finding new avenues to promote muscle recovery when acute skeletal muscle loss extends beyond the natural capacity of the muscle to recover. Maintenance and regeneration of skeletal muscles depend mainly on resident stem cells known as satellite cells. Nevertheless, there are situations in which a significant loss of muscle tissue exhausts the satellite cell pool. For such cases, cell therapy and tissue engineering are becoming promising alternatives. Thus far, attempts to supplement damaged host muscles with donor satellite cells by means of myoblast transplantation therapy were mostly unsuccessful due to massive and rapid loss of donor cells within few hours after transplantation. This study aims at following the effects of low‐energy‐laser irradiation on the fate of implanted myoblasts.Study DesignPrimary myogenic cells, harvested from male rat skeletal muscles, were irradiated with low energy laser, seeded on a biodegradable scaffold and expanded in vitro. The scaffold containing cells was transplanted into partially excised muscles of host female rats. Donor cells were identified in the host muscle tissue, using Y‐chromosome in situ hybridization.ResultsIn this study, we show that laser irradiated donor primary myogenic cells not only survive, but also fuse with host myoblasts to form a host–donor syncytium.ConclusionsOur data show that the use of low energy laser irradiation (LELI), a non‐surgical tool, is a promising means to enhance both the survival and functionality of transplanted primary myogenic cells. Lesers Surg. Med. 40:38–45, 2008. © 2008 Wiley‐Liss, Inc.
Low‐energy laser irradiation increases endothelial cell proliferation, migration, and eNOS gene expression possibly via PI3K signal pathway
Authors: Chen Chung‐Huang , Hung Huey‐Shan , Hsu Shan‐hui 
Published: January 2008

AbstractBackground and ObjectivesThe purpose of this study, therefore, was to determine the mechanisms by which low‐energy laser irradiation (LELI) may exert some of its angiogenic effects via the PI3 kinase/eNOS signaling pathway and induce endothelial cell migration and neovascularization, an important and necessary part of wound healing.Study Design/Materials and MethodsThe possible molecular mechanism of helium–neon (He–Ne) laser irradiation on endothelial cells was proposed. He–Ne laser at 632.5 nm was used to stimulate human umbilical vein endothelial cell (HUVEC), and its effect on cell proliferation, nitric oxide secretion, and cell migration was determined.ResultsIrradiation enhanced endothelial nitric oxidase synthase (eNOS) protein expression, and irradiation of less than 0.26 J/cm2 enhanced eNOS gene expression in HUVEC. The cell migration ability was promoted for HUVEC irradiated with 0.26 J/cm2. This agreed with the vinculin protein expression induced by irradiation. In addition, the angiogenesis was promoted. The induced eNOS expression was inhibited by LY294002, indicating that the effect of laser on EC could be attributed to the up‐regulation of eNOS expression through PI3K pathway at the cellular and molecular levels as a result of the He–Ne laser.ConclusionsThe study has shown that LELI increased endothelial cell proliferation, migration, NO secretion, and identified that activation of PI3K/Akt pathway was a critical step for the elevated for eNOS expression upon LELI. Lesers Surg. Med. 40:46–54, 2008. © 2008 Wiley‐Liss, Inc.
Laser preconditioning of calvarial bone prior to an X‐ray radiation injury: A preliminary in vivo study of the vascular response
Authors: Desmons Sophie O. , Delfosse Caroline J. , Rochon Philippe , Buys Bruno , Penel Guillaume , Mordon Serge 
Published: January 2008

AbstractBackground and ObjectivesThermal preconditioning prior to injury induces a cytoprotective effect on soft tissues and promotes their recovery. Lasers are an adequate tool to generate controlled and reproducible heat. X‐ray irradiation induces a chronic antiangiogenic effect on bone, affecting its healing and remodeling processes. The aim of this study was to investigate the effect of laser preconditioning on the re‐vascularization of X‐ray irradiated bone.Materials and MethodsA bone chamber was implanted onto the calvaria of rabbits to study the vascularization process. Digital pictures were taken of the vascular plexus at the target bone site using a modified digital camera. Vascular density (VD) was determined using image processing. It was defined as the ratio of blood vessel pixels to the total number of pixels to the region of interest. Laser preconditioning was performed with a diode laser (810 nm, 2 W, 3 seconds, 48 J/cm2, 4 mm). A 12‐week follow‐up study was performed on 20 rabbits divided into four groups: #1: control group (n = 5); #2: laser irradiation alone (n = 5). #3: X‐ray radiation (18.75 Gy) alone (n = 5), #4: laser preconditioning 24 hours prior to X‐ray radiation (n = 5).ResultsVD remained stable during the 12‐week follow up for group #1. No significant difference was observed between laser irradiation group (#2) and control group (#1) (P>0.5). The angiolytic action of X‐ray radiation was confirmed in groups #3 and #4, which were statistically different from group #1 (P<0.001). However, the decrease of the vascularization was limited in group #4 highlighting a different evolution between group #3 and #4 (P<0.05). These results were confirmed by histological analysis.Discussion and ConclusionThe bone chamber is an effective reproducible method for the longitudinal analysis of the dynamics of vascularization. Our findings have shown that laser preconditioning is capable of preserving vascularization in an X‐ray irradiated bone site, thus suggesting a novel approach for promoting the healing of bone tissue in which the vascular supply has been damaged. Lesers Surg. Med. 40:28–37, 2008. © 2008 Wiley‐Liss, Inc.
Intrinsic haemangioma of the median nerve: Report of a case and review of the literature
Authors: Vekris Marios D. , Stafilas Kosmas S. , Zacharis Konstantinos X. , Xenakis Theodore A. , Soucacos Panayotis N. , Beris Alexandros E. 
Published: January 2008

AbstractIntrinsic haemangioma of the median nerve is an extremely rare tumor that represents a challenge to diagnose and treat. Only a few cases have been reported in the literature. We present a 10‐year‐old girl who was diagnosed having an intrinsic haemangioma of the median nerve and treated with total surgical resection of the tumor, under high magnification, using microneurolysis and without the need to resect and graft the median nerve. Three years later, the patient is free of symptoms and no recurrence of the mass was noticed. © 2008 Wiley‐Liss, Inc. Microsurgery, 2008.
Localized sensitivity enhanced in vivo 13C MRS to detect glucose metabolism in the mouse brain
Authors: Nabuurs C.I.H.C. , Klomp D.W.J. , Veltien A. , Kan H.E. , Heerschap A. 
Published: January 2008

AbstractThe application of in vivo 13C MR spectroscopy to mouse brain models is potentially valuable for improving the understanding of cerebral carbohydrate metabolism and glutamatergic neurotransmission in various neuropathologies. However, the low sensitivity of 13C nuclei and contaminating signals of lipids in the relatively small mouse brain make this application rather challenging. To meet these technical challenges, localized semi‐adiabatic distortionless enhanced polarization transfer (DEPT) MR spectroscopy in combination with a continuous intravenous [1,6‐13C2] glucose infusion was implemented to detect glucose metabolism in isoflurane‐anesthetized mice at 7T. The signal enhancement and high spectral resolution obtained in these experiments enabled the separate determination of 13C label incorporation into as much as 13 metabolites from a 175 μL volume. Signal increases of glucose (C6), glutamine (C3, C4), and glutamate (C3, C4) were determined with a time resolution of 8.6 min. This study demonstrates an optimized MR method for the application of in vivo 13C MRS in mouse brain. Magn Reson Med, 2008. © 2008 Wiley‐Liss, Inc.
Theory and generalization of monte carlo models of the BOLD signal source
Authors: Martindale John , Kennerley Aneurin J. , Johnston David , Zheng Ying , Mayhew John E. 
Published: January 2008

AbstractThe dependency of the blood oxygenation level dependent (BOLD) signal on underlying hemodynamics is not well understood. Building a forward biophysical model of this relationship is important for the quantitative estimation of the hemodynamic changes and neural activity underlying functional magnetic resonance imaging (fMRI) signals. We have developed a general model of the BOLD signal which can model both intra‐ and extravascular signals for an arbitrary tissue model across a wide range of imaging parameters. The model of the BOLD signal was instantiated as a look‐up‐table (LuT), and was verified against concurrent fMRI and optical imaging measurements of activation induced hemodynamics. Magn Reson Med, 2008. © 2008 Wiley‐Liss, Inc.
High order compact solution of the one‐space‐dimensional linear hyperbolic equation
Authors: Mohebbi Akbar , Dehghan Mehdi 
Published: January 2008

AbstractIn this article, we introduce a high‐order accurate method for solving one‐space dimensional linear hyperbolic equation. We apply a compact finite difference approximation of fourth order for discretizing spatial derivative of linear hyperbolic equation and collocation method for the time component. The main property of this method additional to its high‐order accuracy due to the fourth order discretization of spatial derivative, is its unconditionally stability. In this technique the solution is approximated by a polynomial at each grid point that its coefficients are determined by solving a linear system of equations. Numerical results show that the compact finite difference approximation of fourth order and collocation method produce a very efficient method for solving the one‐space‐dimensional linear hyperbolic equation. We compare the numerical results of this paper with numerical results of (Mohanty, Appl Math Lett 17 (2004), 101–105).© 2008 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq 2008
Jacobi elliptic function solutions of the (1 + 1)‐dimensional dispersive long wave equation by Homotopy Perturbation Method
Authors: Miansari Me. , Ganji D.D. , Miansari Mo. 
Published: January 2008

AbstractIn this article, we try to obtain approximate Jacobi elliptic function solutions of the (1 + 1)‐dimensional long wave equation using Homotopy Perturbation Method. This method deforms a difficult problem into a simple problem which can be easily solved. In comparison with HPM, numerical methods leads to inaccurate results when the equation intensively depends on time, while He's method overcome the above shortcomings completely and can therefore be widely applicable in engineering. As a result, we obtain the approximate solution of the (1 + 1)‐dimensional long wave equation with initial conditions. © 2008 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq 2008
Preparation and characterization of branched and linear sulfonated poly(ether ketone sulfone) proton exchange membranes for fuel cell applications
Authors: Park Hye Seok , Seo Dong Wan , Choi Seung Woo , Jeong Young Gi , Lee Ju Ho , Kim Dong Il , Kim Whan‐Gi 
Published: January 2008

AbstractBranched sulfonated poly(ether ketone sulfone)s (Br‐SPEKS) were prepared with bisphenol A, bis(4‐fluorophenyl)sulfone, 3,3′‐disodiumsulfonyl‐4,4′‐difluorobenzophenone, and THPE (1,1,1‐tris‐p‐hydroxyphenylethane), respectively, at 180 °C using potassium carbonate in NMP (N‐methylpyrrolidinone). THPE, as a branching agent, was used with 0.4 mol % of bisphenol A to synthesize branched copolymers. Copolymers containing 10–50 mol % disulfonated units were cast from dimethylsulfoxide solutions to form films. Linear sulfonated poly(ether ketone sulfone)s (SPEKS) were also synthesized without THPE. The films were converted from the salt to acid forms with dilute hydrochloric acid. A series of copolymers were studied by Fourier transform infrared, 1H‐NMR spectroscopy, differential scanning calorimetry (DSC), and thermogravimetric analysis (TGA). Sorption experiments were conducted to observe the interaction of sulfonated polymers with water and methanol. The ion‐exchange capacity (IEC), a measure of proton conductivity, was evaluated. The synthesized Br‐SPEKS and SPEKS membranes exhibit conductivities (25 °C) from 1.04 × 10−3 to 4.32 × 10−3 S/cm, water swell from 20.18 to 62.35%, IEC from 0.24 to 0.83 mequiv/g, and methanol diffusion coefficients from 3.2 × 10−7 to 4.7 × 10−7 cm2/S at 25 °C. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 1792–1799, 2008
Thermoreversible covalent crosslinking of maleated ethylene/propylene copolymers with diols
Authors: van der Mee M. A. J. , Goossens J. G. P. , van Duin M. 
Published: January 2008

AbstractThe objective of this study is the thermoreversible crosslinking of maleated ethylene/propylene copolymer (MAn‐g‐EPM) using the equilibrium reaction with diols. Covalent hemi‐ester crosslinks are formed via the reaction of anhydrides with alcohols, while an equilibrium shift at elevated temperatures may result in their removal. High conversions to hemi‐ester are obtained at low temperatures in the presence of p‐toluenesulfonic acid, whereas conversions are low at high temperatures. The presence of microphase‐separated aggregates acting as physical crosslinks was demonstrated for MAn‐g‐EPM and all crosslinked materials. The covalent crosslinks were only formed within the aggregates, resulting in stronger aggregates that persisted to higher temperatures. The tensile strength and elasticity were significantly improved upon increasing level of crosslinking, whereas the type of diol has less influence. The covalently crosslinked MAn‐g‐EPM was reprocessable via compression molding at temperatures above 175 °C. Irreversible diester formation occurred for the longer diols, but did not prevent reprocessing, while short diols evaporated. Both effects lowered the level of crosslinking, resulting in significantly changed mechanical properties. The reprocessability does not originate from an equilibrium shift, but from a dynamic exchange between crosslinked and non‐crosslinked functional groups, which allows crosslinks to disconnect and the corresponding chain segments to diffuse between aggregates. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 1810–1825, 2008
Well‐defined complex macromolecular architectures by anionic polymerization of styrenic single and double homo/miktoarm star‐tailed macromonomers
Authors: Driva Paraskevi , Lohse David J. , Hadjichristidis Nikos 
Published: January 2008

AbstractStyrenic single and double star‐tailed macromonomers were synthesized by selective reaction of living homo/miktoarm stars with the chlorosilane groups of 4‐(chlorodimethylsilyl)‐ and 4‐(dichloromethylsilyl)styrene, respectively. The in situ anionic homopolymerization of macromonomers with sec‐BuLi and copolymerization with butadiene and styrene, led to single/double homo/miktoarm star‐tailed molecular brushes and combs, as well as a block copolymer consisting of a linear polystyrene chain and a double miktoarm (PBd/PS) star‐tailed brush‐like block. Molecular characterization by size exclusion chromatography, size exclusion chromatography/two‐angle laser light scattering, and NMR spectroscopy, revealed the high molecular/compositional homogeneity of all intermediate and final products. These are only a few examples of the plethora of complex architectures possible using the above macromonomers. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 1826–1842, 2008
Sorption and swelling of poly(DL‐lactic acid) and poly(lactic‐co‐glycolic acid) in supercritical CO2: An experimental and modeling study
Authors: Pini Ronny , Storti Giuseppe , Mazzotti Marco , Tai Hongyun , Shakesheff Kevin M. , Howdle Steven M. 
Published: January 2008

AbstractTissue engineering scaffolds require a controlled pore size and structure to host tissue formation from cell populations. Supercritical carbon dioxide (scCO2) processing can be used to form porous scaffolds in which the escape of CO2 from a plasticized polymer melt generates gas bubbles that shape the pores. The process is difficult to control with respect to changes in final pore size, porosity, and interconnectivity, while the solubility of CO2 in the polymers strongly affects the foaming process. An in‐depth understanding of polymer CO2 interaction will enable a successful scaffold processing. Amorphous poly(DL‐lactic acid) (PDLLA) and poly(lactic acid‐co‐glycolic acid) (PLGA) polymers are attractive candidates for fabricating scaffolds. In this study, CO2 sorption and swelling isotherms at 35 °C and up to 200 bar on a variety of homo‐ and copolymers of lactic acid and glycolic acids are presented. Sorption is measured through a gravimetric technique using a suspension microbalance and swelling by visualization. The obtained results are modeled using the Sanchez‐Lacombe equation of state. © 2008 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 46: 483–496, 2008
Increase in molecular mobility of an amorphous polymer deformed below Tg
Authors: Munch Etienne , Pelletier Jean‐Marc , Vigier Gérard 
Published: January 2008

AbstractAn extensive mechanical spectroscopy study in the low‐frequency range is proposed to evidence and characterize the effect of a deformation below the glass transition temperature (Tg) on the mobility in an amorphous bisphenol‐A polycarbonate. The mechanical treatment induces the appearance of a peak more than 100 K below Tα, which presents the characteristics of a relaxation associated to an unstable nature. This phenomenon is related to the creation of shear‐induced high‐mobility zones. The characteristics of these zones appear to be independent of the deformation level applied to the system. The use of a specific procedure allows the determination of the values of the apparent activation energy of the mechanism. The apparent activation energy increases continuously from the values of the β‐relaxation to the main α‐relaxation ones. © 2008 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 46: 497–505, 2008