bluuebunny/crossref_metadata_2025_split huggingface dataset:
Different effects of polycyclic aromatic hydrocarbons in artificial and in environmental mixtures on the free living nematode C. elegans
Authors: Liuzzi Vania Cosma , Daresta Barbara Elisabetta , de Gennaro Gianluigi , De Giorgi Carla 
Published: March 2011

ABSTRACTPolycyclic aromatic hydrocarbons (PAHs) are known to exert mutagenic and carcinogenic effects. Research on extracted organic matter (EOM) from environmental mixtures has indicated several mechanisms of intracellular damage in living organisms. The toxic effect of environmental pollutants is usually assessed on cell systems or in single species. We used the model organism Caenorhabditis elegans to compare the effect of synthetic PAHs with that of the EOM from environmental mixtures. The biological effect was measured by monitoring the expression level of some crucial genes, sensitive parameters of the organism's response. The results indicate the ability of C. elegans to counteract damage by mounting a stress‐response only in the presence of EOM. On the other hand the exposure of C. elegans to a mixture of synthetic PAHs determines the silencing of the transcriptional machinery, thus preventing the synthesis of proteins that are important for both the damage repair mechanism and survival itself. The results strongly indicate that the study of environmental toxicant effects at the molecular level may provide information on their mechanism of action. Copyright © 2011 John Wiley & Sons, Ltd.
Neural regrowth induced by PLGA nerve conduits and neurotrophin‐3 in rats with complete spinal cord transection
Authors: Fan Juan , Zhang Hongtian , He Jianghong , Xiao Zhifeng , Chen Bing , Xiaodan Jiang , Dai Jianwu , Xu Ruxiang 
Published: March 2011

AbstractBiomaterials and neurotrophic factors represent two promising strategies for spinal cord injury repair. In this study, a combinatorial approach combining the PLGA nerve conduits and the recombinant human neurotrophin‐3 (rhNT3) was utilized in a spinal cord injury animal model. After complete transection of the thoracic cord in rats, rhNT3 was administered as a single dose to the host cord caudal to a 2‐mm conduit. Axonal regrowth was enhanced, as indicated by immunostaining and neurofilament‐positive area measurement. Neural regrowth was further demonstrated via the retrograde tracing across the lesion. The animals implanted with the PLGA scaffold and rhNT3 exhibited significantly improved performance in BBB rating scale and grid walk tests. These observations suggest that PLGA nerve conduits combined with exogenous NT3 may serve as an alternative therapeutic approach for spinal cord injury repair. © 2011 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2011.
Bringing generalists into the hospital: Outcomes of a family medicine hospitalist model in Singapore
Authors: Hock Lee Kheng , Yang Yong , Soong Yang Kok , Chi Ong Biauw , Seong Ng Han 
Published: March 2011

AbstractPURPOSE:The aim of this study was to assess a newly introduced hospitalist care model in a Singapore hospital. Clinical outcomes of the family medicine hospitalists program were compared with the traditional specialists‐based model using the hospital's administrative database.METHODS:Retrospective cohort study of hospital discharge database for patients cared for by family medicine hospitalists and specialists in 2008. Multivariate analysis models were used to compare the clinical outcomes and resource utilization between patients cared for by family medicine hospitalists and specialist with adjustment for demographics, and comorbidities.RESULTS:Of 3493 hospitalized patients in 2008 who met the criteria of the study, 601 patients were under the care of family medicine hospitalists. As compared with patients cared for by specialists, patients cared for by family medicine hospitalists had a shorter hospital length of stay (adjusted LOS, geometric mean, GM, 4.4 vs. 5.3 days; P < 0.001) and lower hospitalization costs (adjusted cost, GM, $2250.7 vs. $2500.0; P= 0.003), but a similar in‐patient mortality rate (4.2% vs. 5.3%, P= 0.307) and 30‐day all‐cause unscheduled readmission rate (7.5% vs. 8.4%, P= 0.231) after adjustment for age, ethnicity, gender, intensive care unit (ICU) admission, numbers of organ failures, and comorbidities.CONCLUSION:The family medicine hospitalist model was associated with reductions in hospital LOS and cost of care without adversely affecting mortality or 30‐day all‐cause readmission rate. These findings suggest that the hospitalist care model can be adapted for health systems outside North America and may produce similar beneficial effects in care efficiency and cost savings. Journal of Hospital Medicine 2011. © 2011 Society of Hospital Medicine.
Early joint tissue changes are highly correlated with a set of inflammatory and degradative synovial biomarkers after ACL autograft and its sham surgery in an ovine model
Authors: Heard Bryan J. , Achari Yamini , Chung May , Shrive Nigel G. , Frank Cyril B. 
Published: March 2011

AbstractWhile impossible in humans, the mechanisms of early cartilage, bone and meniscal damage can be quantified after anterior cruciate ligament (ACL) injury in animal models. We utilized an ovine model to determine if the mRNA expression of inflammatory and degradative molecules (IL‐1β, IL‐6, MMP‐1, 2, 3, and 13) in the synovium correlated to changes in joint tissues 2 weeks post‐ACL surgery, to test the hypothesis that synovial inflammation is a marker of these changes and possibly their originator. Nine “idealized” ACL autografts were performed and compared with three sham and six normal animals. Using validated protocols, early osteophyte formation, articular cartilage, and meniscal damage were quantified. Synovium was harvested and mRNA expression quantified using qPCR. Multiple linear regression analysis (MLRA) was utilized to correlate synovial mRNA expression in treated and contra‐lateral limbs, from all treatment groups with corresponding joint scores. Synovial mRNA expression was significantly elevated in all experimental and sham joints. The MLRA model was a significant predictive tool (p = 0.001, R2 = 0.70) of gross tissue scores with significant contributions from IL‐1β, IL‐6, and MMP‐3. Findings suggest that this set of synovial biomarkers is predictive (p < 0.009) of early gross changes of joint tissues after arthrotomy and likely directly involved in the relevant mechanisms, particularly early osteophyte formation, in vivo. © 2011 Orthopaedic Research Society Published by Wiley Periodicals, Inc. J Orthop Res 29: 1185–1192, 2011
Effect of fertiliser on functional properties of flour from four rice varieties grown in Sri Lanka
Authors: Gunaratne Anil , Sirisena Nihal , Ratnayaka Upul Kumari , Ratnayaka Jennet , Kong Xiangli , Vidhana Arachchi Lal Peruma , Corke Harold 
Published: March 2011

AbstractBACKGROUND: Fertiliser is an essential agro‐chemical input in modern rice farming. Fertiliser affects the grain quality and yield of rice. Although much research has been carried out to investigate the influence of fertiliser (recommended NPK addition) on yield and quality of rice grain, little is known about the effect of fertiliser on thermal, pasting, gelling and retrogradation properties of rice flour. The aim of this study was to investigate the influence of recommended fertilisation on functional properties of rice flour from four popular high yielding rice varieties grown in Sri Lanka.RESULTS: Fertiliser (recommended NPK addition) increased the protein content but reduced the apparent amylose content in rice flour except in BG 357. Swelling power and amylose leaching of rice flour were also increased. Pasting onset temperature, cold paste viscosity and setback were increased but peak viscosity and granular breakdown decreased. In response to the fertiliser application, gelatinisation peak temperature was reduced in all varieties except BG 300. However, compared to pasting properties, gelatinisation parameters were not much affected by fertilisation. The extent of amylopectin retrogradation was decreased by fertiliser in BG 305 and BG 352 but unchanged in the other two varieties. Except in BG 305, fertiliser reduced the gel hardness of rice flour but increased the gel cohesiveness.CONCLUSION: It is apparent that the increased protein and reduced amylose content caused by fertiliser affect the functional properties of rice flour. Copyright © 2011 Society of Chemical Industry
755 nm alexandrite laser for the reduction of tumor burden in basal cell Nevus syndrome
Authors: Ibrahimi Omar A. , Sakamoto Fernanda H. , Tannous Zeina , Anderson R. Rox 
Published: March 2011

AbstractBackground and ObjectiveBasal Cell Nevus syndrome (BCNS) is characterized by numerous basal cell carcinomas (BCCs). Multiple treatments with the pulsed dye laser (PDL) have been shown, in small studies, to be effective for the treatment of superficial and nodular BCCs. Like PDL, the alexandrite laser can be vessel‐selective, but has the added advantage of deeper tissue penetration. We evaluated the utility of the alexandrite laser in reducing the tumor burden in BCNS with a single treatment.Study Design/Materials and MethodsA case report and review of the literature are presented. A 45‐year‐old man with BCNS and a history of radiation therapy presented with an extraordinarily high tumor burden (>250 BCCs). As a compassionate measure to reduce the tumor burden, we investigated the utility of a single treatment of the long‐pulsed 755 nm alexandrite laser to several BCC lesions. The treated lesions were evaluated at 2‐month and 7‐month clinical follow‐up. Histopathologic analysis of a treated lesion was performed at 7‐month clinical follow‐up.ResultsAt 2‐month, and 7‐month clinical follow‐up, 15 of 18 treated lesions or about 83% of the alexandrite laser treated lesions showed a complete clinical response and appeared as hypopigmented areas with scarring. Histopathologic analysis of a treated lesion at 7‐month clinical follow‐up showed no evidence of residual tumor.ConclusionsThe long‐pulsed alexandrite laser may be helpful in significantly reducing tumor burden in difficult to manage BCNS patients with a single treatment. This provides a facile and practical treatment alternative for the management of challenging cases of BCNS. The limitation of this study is that it is a single case observation. Larger, prospective studies are needed to confirm these observations. Lasers Surg. Med. 42:68–71, 2011 © 2011 Wiley‐Liss, Inc.
Histologic analysis of a 2,940 nm fractional device
Authors: Kist David A. , Elm Courtney M.L. , Eleftheriou Lydia I. , Studer Jessica A. , Wallander Irmina D. , Walgrave Susan E. , Zelickson Brian D. 
Published: March 2011

AbstractBackground and ObjectivesAn evaluation of the histological effects of a 2,940 nm fractional erbium:YAG (Er:YAG) laser device with adjustable depth and coagulation settings in a human abdominoplasty model. The goal of this study was to use light and confocal microscopy to determine the dimensions of the microthermal zones (MTZs) created by this device in the epidermal and dermal layers.Study Design/Materials and MethodsThree subjects were consented and treated after being randomly assigned to a laser depth of either 250 µm, 500 µm, or 1,000 µm. Four coagulation levels were tested in each subject. Two biopsies were taken immediately, 1 and 2 weeks post‐treatment from each zone and viewed by light and confocal microscopy. Two blinded observers examined the sections for changes in collagen and measured depth and width of the MTZs. Coagulation was assessed and recorded as the depth and width of denaturation; measured as the depth and width of ablation plus surrounding thickness of thermal necrosis from dissipated heat.ResultsLight microscopy findings in all treated samples showed a perforated epidermis and dermis immediately after treatment. The depths of ablation produced did not accurately reflect the three different laser settings. Depths of denaturation also did not increase with increased coagulation level settings as expected. The width of ablation in the MTZs, a non‐adjustable setting, was the most accurate and reproducible in all subjects. Confocal microscopy samples revealed the presence of collagen remodeling in the dermis, which increased significantly at 1 and 2 weeks post‐treatment.ConclusionsTreatment with the 2,940 nm Er:YAG device led to significant changes of the dermis at light microscopy levels. The adjustable laser depth and coagulation settings did not produce predictable depths of ablation or denaturation, possibly as a result of the variation of tissue hydration properties among individuals. Increased collagen remodeling was seen in the dermis in all subjects at 1 and 2 weeks post‐treatment. Lasers Surg. Med. 42:79–91, 2011 © 2011 Wiley‐Liss, Inc.
Mass spectrometry‐based holistic analytical approaches for metabolite profiling in systems biology studies
Authors: Theodoridis Georgios , Gika Helen G. , Wilson Ian D. 
Published: March 2011

AbstractMetabonomics and metabolomics represent one of the three major platforms in systems biology. To perform metabolomics it is necessary to generate comprehensive “global” metabolite profiles from complex samples, for example, biological fluids or tissue extracts. Analytical technologies based on mass spectrometry (MS), and in particular on liquid chromatography–MS (LC–MS), have become a major tool providing a significant source of global metabolite profiling data. In the present review we describe and compare the utility of the different analytical strategies and technologies used for MS‐based metabolomics with a particular focus on LC–MS. Both the advantages offered by the technology and also the challenges and limitations that need to be addressed for the successful application of LC–MS in metabolite analysis are described. Data treatment and approaches resulting in the detection and identification of biomarkers are considered. Special emphasis is given to validation issues, instrument stability, and QA/quality control (QC) procedures. © 2011 Wiley Periodicals, Inc., Mass Spec Rev 30:884–906, 2011
Design and synthesis of polytripeptide (leuglnpro)n based upon the matrix protein amelogenin
Authors: Sogah Dotsevi Y. , Perle‐Treves Daniele , Voyer N. , Degrado W. F. 
Published: March 2011

AbstractA linear neutral repetitive peptide, (Leu‐Gln‐Pro)n (n = 1‐100), an analog of the Ca2+ ion‐binding domain of the matrix protein, amelogenin, has been synthesized. The polypeptide is mostly unordered in trifluoroethanol (TFE) at 25°C and its circular dichroism (CD) spectrum resembles that of the protein itself. In TFE the CD spectrum of (Leu‐Gln‐Pro)n reveals that the polypeptide interacts strongly with divalent cations Mg2+, Ca2+, Sr2+, and Ba2+ accompanied by conformational rearrangement from a random to a more‐ordered one. In the presence of Li+, Na+ and K+ ions no such conformational change has been observed. The CD curves of the complexes suggest the presence of type I β‐turns and reinforce the hypothesis that the region Gln112‐Leu138 in amelogenin is the Ca2+‐binding domain. In the solid state, powder X‐ray diffraction suggests that the polymeric (LQP)n may exist as isolated “rigid rods”.
Hybrid materials from organic polymers and inorganic salts
Authors: Köberle Peter , Laschewsky André 
Published: March 2011

AbstractThe prepaparation of amorphous, homogeneous blends of zwitterionic polymers and transition metal salts was investigated. Homogeneous miscibility was achieved in many cases up to equimolar amounts of salt, depending on the anion and cation chosen. Various analytical techniques point to a solid state solution of the inorganic ions in the polymer matrix.
Emulsion polymerization with water soluble comonomers in batch and continuous reactors
Authors: Poehlein Gary W. 
Published: March 2011

AbstractEmulsion copolymerization reactions which include monomers that have significant solubility in the water phase are described and modeled. The reactions that take place in the aqueous phase are considered as is the influence of water‐soluble comonomers on radical transport out of the monomer‐swollen polymer particles. Experimental characterization of the oligomers formed in the aqueous phase is also a subject of this paper.
Cationic latexes as catalytic media
Authors: Ford Warren T. , Lee Jeng‐Jong , Yu Hui , Ackerson Bruce J. , Davis Keith A. 
Published: March 2011

AbstractMonodisperse cationic latexes containing 1–60 mol‐% of quaternary ammonium ion repeat units increase the rates of decarboxylation of 6‐nitro‐benzisoxazole‐3‐carboxylate and of o‐iodosobenzoate‐catalyzed hydrolysis of p‐nitrophenyl diphenyl phosphate by factors of up to 10500 and 6300 compared with the rates in aqueous solutions. The catalytic effects are due more to high local concentrations of reactants in the particles than to increased rate constants of reaction in particles.
Direct measurement of shear forces between polymer‐bearing surfaces sliding past each other
Authors: Klein Jacob , Kumacheva Eugenia , Mahalu Diana , Perahia Dvora 
Published: March 2011

AbstractWe have used a recently developed surface force balance to measure, with extreme sensitivity, both lateral and normal forces between interacting surfaces, for the case of simple liquids and particularly with surface‐attached polymers. The presence of polymers on the surfaces reduces drastically the force required to maintain them in sliding motion, under a given normal load, relative to the bare surface case. We believe this is due to the long range steric repulsion which can sustain a large normal load while maintaining a very fluid interfacial layer. The effect is much more marked for end‐tethered chains in a good solvent than for adsorbed chains in a θ‐solvent. This is attributed to the different extents of interpenetration of the compressed polymer layers.
Environmentally sound manufacturing and polymer industry for the 21st century
Authors: Yoda Naoya 
Published: March 2011

AbstractLife cycle assessments to protect global environment and to control waste in the polymer industry are reviewed. It focused on 1) the environmentally sound technology, 2) the energy conservation, and 3) recycling of industrial products. The competitiveness of a nation depends on how to balance between economic development of sustainable growth and responsible care of global environment in borderless economy. It fully depends on the development of both the environmentally sound manufacturing and the effective products recycling technologies. Current environmental issues of the Japanese chemical industries as well as Toray's performance and new products development for environment business are reviewed; 1) Energy conservation and technology of Japanese manufacturing industry. 2) Development of environmentally sound technology. 3) Effective products recycling technologies, and 4) Sustainable growth of the new chemical age. The future issues of life cycle assessment and environmental protection in manufacturing industries are discussed.
Sophisticated macromolecular structures by cationic ring‐opening polymerizations
Authors: Goethals Eric J. , van Caeter Peter , Du Prez Filip E. , Dubreuil Marjorie F. 
Published: March 2011

AbstractA combination of different types of cationic ring‐opening polymerizations (CROPs) has been used to construct macromolecular structures containing polymer segments with different physicochemical properties. The cyclic monomers used are tetrahydrofuran (THF), N‐tert‐butyl aziridine (TBA), 2‐methyl‐1, 3‐oxazoline (MeOX) and 1, 3‐dioxolane (DXL).The macromolecular structures include different block and graft copolymers, telechelics and macromonomers, star‐ and comb‐shaped polymers, polymer networks and interpenetrating polymer networks (IPNs).
More fun & games with rings, strings & rods
Authors: Gibson Harry W. , Liu Shu , Lee Sang‐Hun , Marand Herve' , Prasad Abaneshwar , Wang Feng , Bheda Mukesh , Nagvekar Devdatt 
Published: March 2011

AbstractThe formation of polyrotaxanes of type 1 by “statistical” threading1 will be described. Examples will include polymerization in the presence of macrocycles and threading of preformed polymers and macrocycles. An analysis of the structural and experimental factors involved in the threading process will be presented. The solution and solid state behavior of the polyrotaxanes will be discussed, including situations in which Tg can be controlled by macrocycles that are compatible with the backbone and situations where the threaded macrocycles crystallize. The preparation of polyrotaxanes of type 3 by threading of polymacrocycles 2 with linear polymers and the resultant changes in physical properties will also be described.
Templated biological synthesis of polymers of abiological monomers
Authors: Kothakota Srinivas , Dougherty Michael J. , Fournier Maurille J. , Mason Thomas L. , Yoshikawa Eiichiro , Tirrell David A. 
Published: March 2011

AbstractA general method for the in vivo incorporation of amino acid analogues into artificial proteins is described. The method involves the construction of an artificial gene encoding the sequence of interest (with the corresponding natural amino acid encoded in place of the analogue), transformation of a bacterial host strain that cannot synthesize the natural amino acid, and induction of protein synthesis in a host culture enriched in the analogue. Results are described for the amino acid analogues selenomethionine, p‐fluorophenylalanine, trifluoroleucine and 3‐thienylalanine.
Secondary doping: A new concept in conducting polymers
Authors: Macdiarmid Alan G. , Epstein Arthur J. 
Published: March 2011

AbstractPhenomenologically, a primary dopant for a conducting polymer is a substance which drastically changes the electronic, optical, magnetic, and/or structural properties of the polymer and is accompanied by a large increase in conductivity. Phenomenologically, a secondary dopant is an apparently “inert” substance which, when applied to a primary‐doped polymer, induces still further changes in the above properties including a further increase in conductivity. The concept of secondary doping will be illustrated using polyaniline and its derivatives.
Epitaxy of helical polyolefins
Authors: Kopp Sophie , Wittmann Jean‐Claude , Lotz Bernard 
Published: March 2011

AbstractThe structural rules which govern the epitaxial crystallisation of polymers ‐ and especially polyolefins ‐ on organic substrates are established. Illustrative examples involve isotactic and syndiotactic polypropylenes and poly( l‐butene). Investigation of the film structure by electron microscopy, electron diffraction and atomic force microscopy reveals some unprecedented features, including in particular the selection of the contact plane according to the chirality of its constituent helices, and direct observation of both right and left hands of polyolefin helices.
Drugs that target dynamic microtubules: A new molecular perspective
Authors: Stanton Richard A. , Gernert Kim M. , Nettles James H. , Aneja Ritu 
Published: March 2011

AbstractMicrotubules have long been considered an ideal target for anticancer drugs because of the essential role they play in mitosis, forming the dynamic spindle apparatus. As such, there is a wide variety of compounds currently in clinical use and in development that act as antimitotic agents by altering microtubule dynamics. Although these diverse molecules are known to affect microtubule dynamics upon binding to one of the three established drug domains (taxane, vinca alkaloid, or colchicine site), the exact mechanism by which each drug works is still an area of intense speculation and research. In this study, we review the effects of microtubule‐binding chemotherapeutic agents from a new perspective, considering how their mode of binding induces conformational changes and alters biological function relative to the molecular vectors of microtubule assembly or disassembly. These “biological vectors” can thus be used as a spatiotemporal context to describe molecular mechanisms by which microtubule‐targeting drugs work.   © 2011 Wiley Periodicals, Inc. Med Res Rev, 31, No. 3, 443‐481, 2011