bluuebunny/crossref_metadata_2025_split huggingface dataset:
Nrf2/HO‐1 pathway activation by manganese is associated with reactive oxygen species and ubiquitin–proteasome pathway, not MAPKs signaling
Authors: Li Huangyuan , Wu Siying , Shi Nian , Lian Shuangqing , Lin Wei 
Published: March 2011

ABSTRACTManganese has been known to induce neurological disorders similar to Parkinson's disease. One of the features of manganese‐induced neurotoxicity is oxidative stress. Accumulating data implicate NF‐E2‐related factor 2 (Nrf2) as a key regulator in the adaptive survival response to oxidative stress. Recent studies suggest that the activation of Nrf2 is induced by manganese in PC12 cells. In the present study, we investigated possible links between reactive oxygen species (ROS), proteasome or mitogen‐activated protein kinase (MAPK) signaling and Nrf2/HO‐1 activation in manganese‐treated PC12 cells. After MnCl2 treatment, there was an increase in nuclear localization and subsequent binding of Nrf2 to the antioxidant‐responsive element (ARE) and upregulation of heme oxygenase‐1 (HO‐1) protein in PC12 cells. Pretreatment with N‐acetyl cysteine, a scavenger of reactive oxygen species, suppressed MnCl2‐induced Nrf2 activation, increase in Nrf2–ARE binding and subsequent upregulation of HO‐1 expression. However, pretreatment with lactacystin, an inhibitor of proteasome activity, enhanced MnCl2‐induced Nrf2 activation, increase in Nrf2–ARE binding and subsequent upregulation of HO‐1 expression. Pretreatment of cells with a pharmacological inhibitor of MAPK (ERK inhibitor PD 98059, P38 inhibitor SB203580 or JNK inhibitor SP600125) did not affect the MnCl2‐induced Nrf2 activation, increase in Nrf2–ARE binding or subsequent upregulation of HO‐1 expression. These results suggest that Nrf2/HO‐1 activation by Mn in PC12 cells is associated with ROS and the ubiquitin–proteasome pathway, not MAPK signaling. Copyright © 2011 John Wiley & Sons, Ltd.
Calcium phosphate combination biomaterials as human mesenchymal stem cell delivery vehicles for bone repair
Authors: Park Sang‐Hyug , Tofighi Aliassghar , Wang Xiaoqin , Strunk Michael , Ricketts Thomas , Chang Jerry , Kaplan David L. 
Published: March 2011

AbstractA new class of biomimetic, bioresorbable apatitic calcium phosphate cement (CPC) was recently developed. The handling characteristics, and the ability to harden at body temperature in the presence of physiological saline, make this material an attractive clinical bone substitute and delivery vehicle for therapeutic agents in orthopedic applications. The major challenge with the material is formulating an injectable paste with options for cell delivery, in order to regenerate new bone faster and with high quality. In this study, three different additives and/or viscosity modifiers (carboxymethylcellulose, silk, and alginate) were incorporated into a CPC matrix. Injectability, cell viability, cell proliferation, surface morphology, and gene expression for osteogenesis of hMSCs were all evaluated. Injectable CPC‐gel composites with cell protection were achieved. The CPC modified with alginate provided the best results based on cell proliferation, ALP and collagen production, and osteogenic transcript increases (for ALP, type I collagen, BSP, and OP). Furthermore, osteogenic analysis indicated lineage‐specific differentiation of hMSCs into osteogenic outcomes. The results suggest that CPC mixed with alginate can be used as a cell delivery vehicle for bone regeneration. © 2011 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2011.
Designed hybrid scaffolds consisting of polycaprolactone microstrands and electrospun collagen‐nanofibers for bone tissue regeneration
Authors: Lee Hyeongjin , Yeo Myunggu , Ahn SeungHyun , Kang Dong‐Oan , Jang Chul Ho , Lee Haengnam , Park Gil‐Moon , Kim Geun Hyung 
Published: March 2011

AbstractBiomedical scaffolds used in bone tissue engineering should have various properties including appropriate bioactivity, mechanical strength, and morphologically optimized pore structures. Collagen has been well known as a good biomaterial for various types of tissue regeneration, but its usage has been limited due to its low mechanical property and rapid degradation. In this work, a new hybrid scaffold consisting of polycaprolactone (PCL) and collagen is proposed for bone tissue regeneration. The PCL enhances the mechanical properties of the hybrid scaffold and controls the pore structure. Layered collagen nanofibers were used to enhance the initial cell attachment and proliferation. The results showed that the hybrid scaffold yielded better mechanical properties of pure PCL scaffold as well as enhanced biological activity than the pure PCL scaffold did. The effect of pore size on bone regeneration was investigated using two hybrid scaffolds with pore sizes of 200 ± 20 and 300 ± 27 μm. After post‐seeding for 7 days, the cell proliferation with pore size, 200 ± 20 μm, was greater than that with pore size, 300 ± 27 μm, due to the high surface area of the scaffold. © 2011 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2011.
ROCK1 as a potential therapeutic target in osteosarcoma
Authors: Liu Xianzhe , Choy Edwin , Hornicek Francis J. , Yang Shuhua , Yang Cao , Harmon David , Mankin Henry , Duan Zhenfeng 
Published: March 2011

AbstractOsteosarcoma is the most common primary malignancy of bone. Patients with localized disease are routinely treated with surgery and chemotherapy. Unfortunately, many of these patients eventually relapse even after high‐dose pre‐ and postoperative chemotherapy. Upon recurrence of the tumor locally or distantly, they have limited treatment options that are usually unsuccessful. Our prior studies screening lentiviral shRNA libraries, searching for kinases involved in osteosarcoma cell growth and proliferation have identified the Rho‐associated coiled‐coil containing protein kinase 1 (ROCK1) as a possible hit. We show in this study that ROCK1 is highly expressed in various tumor cell lines and tumor tissues from osteosarcoma patients. ROCK1 knockdown by synthetic siRNA decreases cell proliferation, viability and induces apoptosis in osteosarcoma cell lines KHOS and U‐2OS. Finally, we established the relationship between expression levels of ROCK1 and clinical prognosis in osteosarcoma patients by using immunohistochemistry. There were significant differences in overall survival between cohorts of patients with ROCK1 levels categorized as high‐staining, moderate‐staining, and low‐staining. High levels of ROCK1 were associated with poor outcomes in clinical osteosarcoma. These findings suggest that knockdown of ROCK1 inhibits proliferation and induces apoptosis in osteosarcoma cell lines. ROCK1 may be a promising therapeutic target for the treatment of osteosarcoma patients. © 2011 Orthopaedic Research Society Published by Wiley Periodicals, Inc. J Orthop Res 29: 1259–1266, 2011
Mechanisms and fast kinetics of the catastrophic optical damage (COD) in GaAs‐based diode lasers
Authors: Tomm J.W. , Ziegler M. , Hempel M. , Elsaesser T. 
Published: March 2011

AbstractCOD diagram determined for a batch of broad‐area AlGaAs diode lasers. The time to COD within a single current pulse is plotted versus the actual average optical power in the moment when the COD takes place. Full circles stand for clearly identified COD events (right ordinate), whereas open circles (left ordinate) represent the pulse duration in experiments, where no COD has been detected. A borderline (gray) exists between two regions, i. e., parameter sets, of presence (orange) and absence of COD (blue). This borderline is somewhat blurred because of the randomness in filamentation of the laser nearfield and scatter in properties of the involved individual devices.
Pulsed dye laser as a novel non‐surgical treatment for basal cell carcinomas: Response and follow up 12–21 months after treatment
Authors: Konnikov Nellie , Avram Mathew , Jarell Abel , Tannous Zeina 
Published: March 2011

AbstractBackground and ObjectiveWe showed previously that pulsed dye laser (PDL) is a potentially effective therapy for BCCs <15 mm on trunk and extremities. To follow‐up, we conducted a study based on optimized parameters and expanded the duration of the study to at least 1 year after treatment.Materials and MethodsFourteen patients with 20 biopsy‐proven BCCs on trunk and extremities, 8–35 mm in diameter, were treated. Each BCC received four consecutive PDL treatments at 3–4 week intervals. A 4 mm margin of clinically normal skin was also treated. Standardized photography was performed prior to each treatment and follow up visit. Patients were asked to consent for standard excision or at least scouting biopsies after treatment completion.ResultsComplete clinical response was seen with 19 of 20 treated BCCs, regardless of size and histologic subtype. One did not respond completely to therapy. All remaining 19 BCCs were followed between 12 and 21 months (median = 18 months) after the last PDL treatment. Of these 19 BCCs, only one recurred at 17 months follow up. The remaining 18 BCCs did not show any clinical signs of residual or recurrent tumor at 12–21 months follow‐up. Overall, 90% (18/20 tumors) of treated BCCs in this study showed no clinical or histologic evidence of BCC more than 12 months after PDL treatment. Additionally, 18/19 (95%) BCCs less than or equal to 17 mm showed no evidence of residual or recurrent tumor clinically or on histology 12–21 months post‐laser treatment.ConclusionsPDL treatment of BCC represents a novel, quick, and relatively non‐painful treatment that does not usually produce scar and may represent an alternative treatment for certain types of BCC in the appropriate clinical setting. This study confirms prior findings regarding the efficacy of PDL in the treatment of BCC, with longer follow‐up period. Lasers Surg. Med. 42:72–78, 2011 © 2011 Wiley‐Liss, Inc.
A comparison of Q‐switched and long‐pulsed alexandrite laser for the treatment of freckles and lentigines in oriental patients
Authors: Ho S.G.Y. , Yeung C.K. , Chan N.P.Y. , Shek S.Y. , Chan H.H.L. 
Published: March 2011

AbstractBackgroundQ‐switched (QS) lasers are effective in the treatment of freckles and lentigines in Type I and II skin, with minimal adverse effects. Long pulsed (LP) lasers have been proposed to be more suitable for treatment of darker skin types.ObjectivesTo investigate the efficacy and adverse effects of using QS or LP Alexandrite laser for the treatment of freckles and lentigines in Oriental patients.MethodsA prospective split‐face study of 20 Chinese patients who were randomly assigned to undergo a single QS (50 nanosecond) or LP (100 microseconds) laser treatment to either side of their face was carried out. Two blinded physicians assessed clinical efficacy using visual analogue scales of pre‐ and post‐treatment photographs. Subjective assessment was evaluated using questionnaires which detailed the degree of pain, erythema and edema sustained during treatment, and improvement and satisfaction levels at 4, 8, and 12 weeks.ResultsThere was statistically significant improvement in pigmentation (P < 0.05) in both groups throughout the study, with no statistical difference found between the groups. Postinflammatory hyperpigmentation was more frequently found after QS treatment (22%), compared to LP treatment (6%). Majority of patients reported moderate to marked improvement in pigmentation throughout the study with both pulse widths, and correspondingly high levels of satisfaction rates. More severe pain, erythema and edema were experienced during QS Alexandrite treatment.ConclusionLP Alexandrite is quick and effective, and carries a lower risk of adverse effects than QS Alexandrite, for the removal of freckles and lentigines in darker skin types. Lasers Surg. Med. 42:108–113, 2011 © 2011 Wiley‐Liss, Inc.
Direct‐EI in LC–MS: Towards a universal detector for small‐molecule applications
Authors: Cappiello Achille , Famiglini Giorgio , Palma Pierangela , Pierini Elisabetta , Termopoli Veronica , Trufelli Helga 
Published: March 2011

AbstractThis review article will give an up‐to‐date and exhaustive overview on the efficient use of electron ionization (EI) to couple liquid chromatography and mass spectrometry (LC–MS) with an innovative interface called Direct‐EI. EI is based on the gas‐phase ionization of the analytes, and it is suitable for many applications in a wide range of LC‐amenable compounds. In addition, thanks to its operating principles, it prevents unwelcome matrix effects (ME). In fact, although atmospheric pressure ionization (API) methodologies have boosted the use of LC–MS, the related analytical methods are sometime affected by inaccurate quantitative results, due to unavoidable and unpredictable ME. In addition, API's soft ionization spectra always demand for costly and complex tandem mass spectrometry (MS/MS) instruments, which are essential to acquire an “information‐rich” spectrum and to obtain accurate quantitative information. In EI a one‐stage analyzer is sufficient for a qualitative investigation and MS/MS detection is only used to improve sensitivity and to cut chemical noise. The technology illustrated here provides a robust and straightforward access to classical, well‐characterized EI data for a variety of LC applications, and readily interpretable spectra for a wide range of areas of research. The Direct‐EI interface can represent the basis for a forthcoming universal LC–MS detector for small molecules. © 2010 Wiley Periodicals, Inc., Mass Spec Rev 30:1242–1255, 2011
Trimethylsilylmethyllithium: A novel initiator for the anionic polymerization of cyclosiloxanes and vinyl monomers
Authors: Zundel Thomas , Yu Jian Ming , De France Collège 
Published: March 2011

AbstractTrimethylsilylmethyllithium has been successfully used for the ring opening polymerization of cyclosiloxanes, in toluene or in the bulk, with the [211] cryptand or DMSO as promoters. Initiation reaction has been followed by 1H, 13C, 29Si and 7Li NMR in the case of D3 and D4 polymerizations. Suitable conditions have been found in which monomodal distributions of molecular weights of polysiloxanes are observed even in the case of D4 and 1,3,5,7‐tetramethyl‐1,3,5,7‐tetravinylcyclotetrasiloxane homopolymerizations and copolymerizations. This organolithium compound can also initiate the anionic polymerization of vinyl monomers such as butadiene, styrene and MMA.
Synthesis and applications of porous spg (shirasu porous glass) microspheres
Authors: Omi Shinzo , Katami Ken'Ichi , Taguchi Tetsuya , Kaneko Kazuyoshi , Iso Mamoru 
Published: March 2011

AbstractFairly uniform porous microspheres of poly(styrene) (PS) and poly(methyl methacrylate) (PMMA) were synthesized using a particular microporous glass membrane (SPG). Average diameters of these spheres are from 2.5 to 38 μm with the coefficient of variation (CV) around 10%. A maximum specific surface area of 370 m2 /g was achieved. Uniform dispersion of MMA droplets was successfully prepared only when the swelling process reported by Higuchi and Misra was adopted. Two potential applications, one as a packing material for column chromatography, and the other as a carrier of enzyme immobilization, were demonstrated.
Direct non‐radiative energy transfer studies of interdiffusion latex films: Strategies for data analysis
Authors: Winnik Mitchell A. , Liu Yuan Sheng 
Published: March 2011

AbstractWe are interested in studying polymer diffusion across an interface by direct non‐radiative energy transfer. In this paper we examine different approaches and techniques to analyze fluorescence decay data in such systems. One type of technique is used to calculate a parameter fm characterizing the extent of mixing. A second technique allows the concentration profile of the acceptor dyes at the interface to be evaluated. The third technique introduces the diffusion model into the decay profile analysis and yields the diffusion coefficient of the polymers. We found that when characterizing the extent of interdiffusion using the fraction parameter fm, ignorance of the detailed concentration gradient does not introduce significant error. The evaluation of diffusion coefficients is a complicated task due to the broad distribution of polymer molecules in latex films.
Dynamic interactions and adsorption in systems of hydrophobically modified water‐soluble polymers
Authors: Hansen Finn Knut , Nyström Bo , Walderhaug Harald , Larsen Børve Kjetil 
Published: March 2011

AbstractAssociating polymers are prepared from poly(oxyelliylene) and a diisocyanate and terminated by linear alcohols with 8 to 18 C‐atoms. Solutions of these polymers in pure water and with surfactants have been investigated by dynamic light scattering and NMR self‐diffusion. The diffusion results indicate that the polymers in solution form heterodisperse clusters that show a complex behavior of overlap and coupling to each other, a feature which may be described by the coupling theory of Ngai and coworkers. In addition competitive adsorption on polystyrene latex particle is measured and the results indicate a multilayer adsorption structure that is broken down by surfactant addition. Surfactant adsorption seems to be practically independent of adsorbed polymer, except for an “initial inhibition” concentration that may be connected to the desorption of secondary layers of adsorbed polymer.
Novel polymerizations of germylenes and their reaction mechanisms
Authors: Kobayashi Shiro , Shoda Shin‐Ichiro , Iwata Satoru , Hiraishi Masafumi , Cao Shaokui 
Published: March 2011

AbstractNovel copolymerizations for the synthesis of germanium‐containing polymers using a divalent germanium species, germylene, have been developed. The copolymerization involves a redox process between a germylene (Mred) and an oxidant monomer (Mox) such as p‐benzoquinones, cyclic α,β‐unsaturated ketones, and substituted acetylenes. A new germanium‐containing polymer having a germanium‐sulfur bond unit in the main chain has been synthesized by the oxidative addition of a poly(dithioalkylene) toward the germylene. A ligand exchange polymerization has been developed as a new polymerization reaction affording a polygermane. The reaction mechanism of the copolymerization between germylene and p‐benzoquinone derivatives has definitely been established as a biradical polymerization system involving a germyl radical and a semiquinone radical, providing the first clear‐cut evidence for a biradical mechanism in the polymerization chemistry.
Chain transfer by radical addition‐fragmentation mechanisms: Synthesis of macromonomers and end‐functional oligomers
Authors: Rizzardo Ezio , Meijs Gordon F. , Thang San H. 
Published: March 2011

AbstractAppropriately substituted allylic sulfides, sulfones, bromides, phosphonates, stannanes and peroxides, vinyl ethers and thionocarbonyl compounds are effective chain transfer agents in free radical polymerizations. These compounds function by a radical addition‐fragmentation mechanism by which fragments derived from the chain transfer agents are installed at both ends of polymer chains. This provides a convenient method for preparing both mono‐ and di‐end functional oligomers and polymers. Allylic peroxides fragment to give epoxy end groups while the other allylic compounds give rise to macromonomers by introducing terminal double bonds.
Dendritic resins for coating applications
Authors: Hult Anders , Johansson Mats , Malmström Eva 
Published: March 2011

AbstractHyperbranched, aliphatic polyesters of theoretically calculated molar masses 1 200–44 300 (2–7 generations) were synthesized in the molten state from 2, 2‐bis(hydroxymethyl)propionic acid (bis‐MPA) (repeating unit of ABx‐type) and 2‐ethyl‐2‐(hydroxymethyl)‐1, 3‐propanediol (TMP) (core molecule) using acid catalysis. The synthetic procedure was a pseudo‐one‐step divergent reaction. The degree of branching was found to be near 80 %. A study has also been made with respect to the rheological properties of the hyperbranched aliphatic polyesters. The polymers exhibit an almost newtonian behaviour in the molten state. They also exhibit a lower increase in viscosity with molecular weight than linear polymers. The surface functionality is shown to greatly affect the viscosity of the polymers.
Polymer research in industry: Quo vadis?
Authors: Cherdron Harald 
Published: March 2011

AbstractEven more than in the past, the polymer industry has to adapt its future strategy to a changing environment. This has, of course, also a great influence on industrial research and development activities. An attempt will be made to give answers on how industrial polymer research is going to live with this situation.The lecture is divided into 3 chapters:• Quo vadis Polymer Synthesis• Quo vadis Polymer Products• Effects on R & D‐Strategy and ‐OrganizationEach chapter begins with general remarks and ends with some detailed examples. The chapter on future R & D‐Strategy and ‐Organization also contains some comments on the future role of polymer research in academia.
An extended Abstract of this lecture has been published as:
An industrial view of polymer science in the next decade
Authors: Wirth Joseph G. 
Published: March 2011

AbstractNearly thirty years go when I left graduate school at the University of Michigan and joined General Electric's Research Laboratory, I was impressed by the diversity and vitality of the polymer industry worldwide and by the opportunities for polymer science and technology to make that industry even larger, stronger and more diverse. Most of all, I was excited at the prospect of being a contributor to that future. I'm still excited to be a part of that industry and especially pleased at this conference to be in the presence of the many outstanding individuals who have created today's polymer science and technology, and to be in the presence of those who will create tomorrow's.
High performance transparent polymers: Progress and prospects
Authors: Ledwith Anthony 
Published: March 2011

AbstractApart from packaging there are a number of important applications of polymers for which (mainly) visible light transmission and/or optical refractive power are especially important. These include the use of plastics in all types of glazings for buildings and transportation, the use of solid polymers and hydrogels in ophthalmics and the growing utilization of polymeric disc substrates for a variety of data storage and video reproduction systems. However, although this range of applications is very broad, it is remarkable that only a few polymer types currently meet the demanding material specifications. Outstanding examples include poly(vinylbutyral)1 for glass‐laminated safety/security glazings, the crosslinked polymeric resin obtained by free radical polymerization of diethylene glycol‐bisallyl carbonate (CR39 monomer) for spectacle lenses,2 and polycarbonates for monolithic glazings, ophthalmics and disc substrates. In many applications, the polymeric material must compete on performance and price with more traditional inorganic glasses and this has led directly to the current drive to combine properties of glass and plastics via both (complex laminates) and chemical methods (utilization of the versatile silicate network formation to crosslink or incorporate low molecular weight polymeric species).3This presentation will survey material requirements in the field of transparent plastics and use the well established benefits and problems of today's materials as a pointer to the types of molecular organizations, morphologies and property enhancing coatings likely to be required in the future.