bluuebunny/crossref_metadata_2025_split huggingface dataset:
Controlling the structure and rheology of polyimide/nanoclay composites by condensation polymerization
Authors: Wang Jia , Iroh Jude O. , Long Amy 
Published: January 2012

AbstractA novel in situ condensation polymerization method for controlling the structure and dispersion of clay in the polyimide (PI) matrix has been investigated. Initially, the viscosity of the polymerizing poly(amic acid) (PAA) solution increases rapidly with increasing shear rate and polymerization time. In the presence of clay, the PAA solution viscosity became significantly higher than that for the neat PAA solution at initial polymerization stage; however, it attained a final value, which was significantly lower than that for a neat PAA solution after a long polymerization time. The PAA/clay solution synthesized by in situ polycondensation reaction also showed an interesting optical activity between 500 and 600 nm. The PAA/clay solution prepared by a two‐step method involving polymerization followed by the addition of clay shows no unusual optical behavior above 400 nm. The imidization of PAA is enhanced in the presence of clay. The imidization temperature decreased significantly in the presence of clay, and the extent of imidization increased with increasing amount of clay and cure temperature. X‐ray diffraction and microscopy studies show the existence of exfoliated clays at low concentration of clay and at high curing temperatures. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Effect of scratch velocity on scratch behavior of injection‐molded polypropylene
Authors: Chivatanasoontorn Vadee , Aoki Naoya , Kotaki Masaya 
Published: January 2012

AbstractScratch tests of polypropylene injection moldings were conducted with a progressive load scratch test according to ISO 19252. Effect of scratch velocity on scratch visibility and damage initiation was investigated. The results showed that the critical normal load for onset of scratch visibility was independent of scratch velocity in the range from 1 to 10 mm/s. However, the critical normal load decreased with increase of scratch velocity higher than 10 mm/s. The other scratch damage transitions such as onset of fish‐scale and cutting pattern, the critical normal load also decreased with increase of scratch velocity. A correlation between scratch behavior and subsurface deformation was observed by polarized optical microscope. The formation of yielded zone under scratch groove was clearly observed at onset of scratch visibility. It was found that the yielded zone size becomes shallower at higher scratch velocity. The results suggested that localized stress was generated near the surface at higher scratch velocity. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Synthesis of fluorescent poly(1‐vinylimidazole‐co‐(1‐pyrene) methyl 2‐methyl‐2‐propenote) and determination of monomer reactivity ratios
Authors: Yan Yehai , Lu Na , Cui Jian , Zhang Jinfang 
Published: January 2012

AbstractA new fluorescent copolymer, poly(1‐vinylimidazole‐co‐(1‐pyrene) methyl 2‐methyl‐2‐propenote) (VI‐co‐PyMMP), has been designed and synthesized by a free‐radical copolymerization of VI and PyMMP as well as characterized using ultraviolet (UV), Fourier transform infrared spectroscopy (FTIR), 1H NMR, and fluorescence spectroscopies. The monomer reactivity ratios are determined by two methods of Fineman‐Ross (r1 = 0.28 ± 0.04 for VI, r2 = 1.32 ± 0.11 for PyMMP) and Kelen‐Tüdös (r1 = 0.23 ± 0.05, r2 = 1.22 ± 0.12). Based on the reactivity ratios, the monomer sequence lengths and Q and e for PyMMP monomer are further calculated. The results suggest that the copolymerization of VI and PyMMP is a nonideal copolymerization without an azeotropic point (i.e., r1 < 1, r2 > 1 and r1r2 < 1) and has a low alternation tendency. The conclusions drawn in this work may not only direct the later synthesis of the copolymers but also enrich the database of free‐radical copolymerization. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Influence of a pore‐forming agent on swelling, network parameters, and permeability of poly(ethylene glycol)‐crosslinked poly(methyl vinyl ether‐co‐maleic acid) hydrogels: Application in transdermal delivery systems
Authors: Raj Singh Thakur Raghu , Garland Martin J. , Migalska Katarzyna , Salvador Ester Caffarel , Shaikh Rahamatullah , McCarthy Helen O. , David Woolfson A. , Donnelly Ryan F. 
Published: January 2012

AbstractWe characterized hydrogels, prepared from aqueous blends of poly(methyl vinyl ether‐co‐maleic acid) (PMVE/MA) and poly(ethylene glycol) (PEG 10,000 Daltons) containing a pore‐forming agent (sodium bicarbonate, NaHCO3). Increase in NaHCO3 content increased the equilibrium water content (EWC) and average molecular weight between crosslinks (Mc) of hydrogels. For example, the %EWC was 731, 860, 1109, and 7536% and the Mc was 8.26, 31.64, 30.04, and 3010.00 × 105 g/mol for hydrogels prepared from aqueous blends containing 0, 1, 2, and 5% w/w of NaHCO3, respectively. Increase in NaHCO3 content also resulted in increased permeation of insulin. After 24 h, percentage permeation was 0.94, 3.68, and 25.71% across hydrogel membranes prepared from aqueous blends containing 0, 2, and 5% w/w of NaHCO3, respectively. Hydrogels containing the pore‐forming agent were fabricated into microneedles (MNs) for transdermal drug delivery applications by integrating the MNs with insulin‐loaded patches. It was observed that the mean amount of insulin permeating across neonatal porcine skin in vitro was 20.62% and 52.48% from hydrogel MNs prepared from aqueous blends containing 0 and 5% w/w of NaHCO3. We believe that these pore‐forming hydrogels are likely to prove extremely useful for applications in transdermal drug delivery of biomolecules. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Cooperative effect of molecular orientation and β‐form on toughening injection‐molded isotactic polypropylene with β‐nucleating agent
Authors: Lv Ruihua , Li Zhujun , Na Bing , Zou Shufen , Pan Huayan 
Published: January 2012

AbstractThe toughness of conventional injection‐molded isotactic polypropylene bars has been investigated with respect to the notch location and β‐nucleating agent. Superior toughness is achieved in the β‐nucleated bars with notches near the gate, but is absent in the near‐gate bars without β‐nucleating agent or in the β‐nucleated ones far from the gate. With detailed structural analysis across the sample thickness, it is indicated that in these tough bars, extensive flow close to the surface suppresses the formation of β‐form to a large extent but favors the generation of oriented α‐form, whereas toward inner region, an opposite tendency is presented with the decay of flow strength and the activation of β‐nucleating agent. Allowing that this peculiar hierarchical structure is absent in other two kinds of bars, it is deduced that the cooperative effect of molecular orientation of α‐form in the skin layer and rich β‐form in the inner region is responsible for the significant toughness enhancement in the β‐nucleated bars near the gate. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Dual regulation of metalloproteinase expression in chondrocytes by Wnt‐1–inducible signaling pathway protein 3/CCN6
Authors: Baker Natasha , Sharpe Paul , Culley Kirsty , Otero Miguel , Bevan Damon , Newham Peter , Barker Wendy , Clements Kristen M. , Langham Caroline J. , Goldring Mary B. , Gavrilović Jelena 
Published: January 2012

AbstractObjectiveWnt‐1–inducible signaling pathway protein 3 (WISP‐3)/CCN6 is mutated in progressive pseudorheumatoid dysplasia and may have effects on cartilage homeostasis. The aim of this study was to ascertain additional roles for WISP‐3/CCN6 by determining its expression in osteoarthritic (OA) cartilage and by investigating its effects on cartilage‐relevant metalloproteinase expression in immortalized (C‐28/I2) and primary chondrocytes.MethodsCartilage steady‐state levels of WISP‐3/CCN6 messenger RNA and protein production were determined by real‐time quantitative reverse transcription–polymerase chain reaction (RT‐PCR) and immunohistochemistry, respectively. WISP‐3/CCN6 was overexpressed in C‐28/I2 cells, and the resultant clones were analyzed by quantitative RT‐PCR. The stable clones were analyzed by RT‐PCR for metalloproteinase expression, and the signaling pathways involved were investigated using pharmacologic inhibition. The effects of WISP‐3/CCN6 on metalloproteinase expression in primary chondrocytes were investigated using a small interfering RNA approach.ResultsWISP‐3/CCN6 was highly expressed in OA cartilage compared with undamaged cartilage, at both the RNA and protein levels. WISP‐3/CCN6 overexpression in C‐28/I2 cells resulted in unexpected dual regulation of metalloproteinases; expression of the potent aggrecanase ADAMTS‐5 was down‐regulated 9‐fold, while expression of MMP‐10 was up‐regulated 14‐fold, and these responses were accentuated in the WISP‐3/CCN6 clones grown in suspension. MMP‐10 up‐regulation was dependent on several MAPKs, but WISP‐3/CCN6–mediated ADAMTS‐5 repression was independent of these pathways and was partially relieved by activation of β‐catenin signaling. WISP‐3/CCN6 also suppressed ADAMTS‐5 expression in C‐28/I2 cells treated with cytokines. In cytokine‐treated primary chondrocytes, gene silencing of WISP‐3/CCN6 resulted in enhanced ADAMTS‐5 expression, while MMP‐10 expression was suppressed.ConclusionWISP‐3/CCN6 was highly expressed in end‐stage OA cartilage, suggesting a role for this growth factor in cartilage homeostasis. WISP‐3/CCN6–induced repression of ADAMTS‐5 expression and regulation of MMP‐10 expression suggest complex and context‐dependent roles for WISP‐3/CCN6 in cartilage biology.
Brief Report: Decreased intrinsic brain connectivity is associated with reduced clinical pain in fibromyalgia
Authors: Napadow Vitaly , Kim Jieun , Clauw Daniel J. , Harris Richard E. 
Published: January 2012

AbstractObjectiveA major impediment to the development of novel treatment strategies for fibromyalgia (FM) is the lack of an objective marker that reflects spontaneously reported clinical pain in patients with FM. Studies of resting‐state intrinsic brain connectivity in FM have demonstrated increased insular connectivity to the default mode network (DMN), a network whose activity is increased during nontask states. Moreover, increased insular connectivity to the DMN was associated with increased spontaneous pain levels. However, as these analyses were cross‐sectional in nature, they provided no insight into dynamic changes in connectivity or their relationship to variations in self‐reported clinical pain. The purpose of this study was to evaluate longitudinal changes in the intrinsic brain connectivity of FM patients treated with nonpharmacologic interventions known to modulate pain levels in this patient population, and to test the hypothesis that the reduction of DMN–insula connectivity following therapy would correlate with diminished pain.MethodsSeventeen FM patients underwent resting‐state functional magnetic resonance imaging at baseline and following 4 weeks of a nonpharmacologic intervention to diminish pain. Intrinsic DMN connectivity was evaluated using probabilistic independent components analysis. Longitudinal changes in intrinsic DMN connectivity were evaluated by paired analysis, and correlations between longitudinal changes in clinical pain and changes in intrinsic DMN connectivity were investigated by multiple linear regression analysis. Changes in clinical pain were assessed with the short form of the McGill Pain Questionnaire (SF‐MPQ).ResultsClinical pain as assessed using the sensory scale of the SF‐MPQ was reduced following therapy (P = 0.02). Intrinsic DMN connectivity to the insula was reduced, and this reduction correlated with reductions in pain (corrected P < 0.05).ConclusionOur findings suggest that intrinsic brain connectivity can be used as a candidate objective marker that reflects changes in spontaneous chronic pain within individual FM patients. We propose that intrinsic connectivity measures could potentially be used in either research or clinical settings as a complementary, more objective outcome measure for use in FM.
Inflammatory regulation of glucocorticoid metabolism in mesenchymal stromal cells
Authors: Ahasan Mohammad M. , Hardy Rowan , Jones Christopher , Kaur Kirren , Nanus Dominika , Juarez Maria , Morgan Stuart A. , Hassan‐Smith Zaki , Bénézech Cécile , Caamaño Jorge H. , Hewison Martin , Lavery Gareth , Rabbitt Elizabeth H. , Clark Andrew R. , Filer Andrew , Buckley Christopher D. , Raza Karim , Stewart Paul M. , Cooper Mark S. 
Published: January 2012

AbstractObjectiveTissue glucocorticoid (GC) levels are regulated by the GC‐activating enzyme 11β‐hydroxysteroid dehydrogenase type 1 (11β‐HSD1). This enzyme is expressed in cells and tissues arising from mesenchymal stromal cells. Proinflammatory cytokines dramatically increase expression of 11β‐HSD1 in stromal cells, an effect that has been implicated in inflammatory arthritis, osteoporosis, obesity, and myopathy. Additionally, GCs act synergistically with proinflammatory cytokines to further increase enzyme expression. The present study was undertaken to investigate the mechanisms underlying this regulation.MethodsGene reporter analysis, rapid amplification of complementary DNA ends (RACE), chemical inhibition experiments, and genetic disruption of intracellular signaling pathways in mouse embryonic fibroblasts (MEFs) were used to define the molecular mechanisms underlying the regulation of 11β‐HSD1 expression.ResultsGene reporter, RACE, and chemical inhibitor studies demonstrated that the increase in 11β‐HSD1 expression with tumor necrosis factor α (TNFα)/interleukin‐1β (IL‐1β) occurred via the proximal HSD11B1 gene promoter and depended on NF‐κB signaling. These findings were confirmed using MEFs with targeted disruption of NF‐κB signaling, in which RelA (p65) deletion prevented TNFα/IL‐1β induction of 11β‐HSD1. GC treatment did not prevent TNFα‐induced NF‐κB nuclear translocation. The synergistic enhancement of TNFα‐induced 11β‐HSD1 expression with GCs was reproduced by specific inhibitors of p38 MAPK. Inhibitor and gene deletion studies indicated that the effects of GCs on p38 MAPK activity occurred primarily through induction of dual‐specificity phosphatase 1 expression.ConclusionThe mechanism by which stromal cell expression of 11β‐HSD1 is regulated is novel and distinct from that in other tissues. These findings open new opportunities for development of therapeutic interventions aimed at inhibiting or stimulating local GC levels in cells of mesenchymal stromal lineage during inflammation.
Influence of Process Parameters on Mechanical Properties of Nanoparticulate Coatings
Authors: Barth Nina , Schilde Carsten , Kwade Arno 
Published: January 2012

AbstractDie Erzeugung dünner partikulärer Schichten, die mit einem Filmziehgerät auf feste Edelstahl‐Substrate aufgetragen wurden, wurde untersucht. Die hierfür verwendeten pyrogenen Al2O3‐Nanopartikel (x50 = 139 nm) wurden mit einer Dreiwalze in Wasser dispergiert. Mittels Nanoindentation wurde der Einfluss der Spalthöhe und der Trocknungstemperatur auf die mechanischen Eigenschaften untersucht. Wobei insbesondere auch die Methodenetablierung der Nanoindentation für dünne partikuläre Schichten diskutiert wird. Die Nanoindentation zeigte sich als eine leistungsfähige Methode, um die mechanischen Eigenschaften dieser Schichten zu untersuchen. Der Substrateinfluss konnte für Schichtdicken größer 10 μm oder sehr geringe Indentationstiefen ausgeschlossen werden.
Surface Functionalization of Toner Particles for the Assembly of Three‐Dimensional Objects via Click Chemistry
Authors: Speyerer Christian , Borchers Kirsten , Güttler Stefan , Tovar Günter , Hirth Thomas , Weber Achim 
Published: January 2012

AbstractIn diesem Artikel wird die Entwicklung von Polyacrylat‐Partikeln als potenzielles Tonermaterial für ein elektrophotographisches Rapid‐Prototyping‐Verfahren beschrieben, mit dessen Hilfe in Zukunft dreidimensionale Objekte aus verschiedenen Tonern aufgebaut werden können. Die Polyacrylat‐Partikel wurden an der Oberfläche funktionalisiert, um einen dreidimensionalen Aufbau mittels Klick‐Chemie zu ermöglichen.
Therapeutic misconception, misestimation, and optimism in participants enrolled in phase 1 trials
Authors: Pentz Rebecca D. , White Margaret , Harvey R. Donald , Farmer Zachary Luke , Liu Yuan , Lewis Colleen , Dashevskaya Olga , Owonikoko Taofeek , Khuri Fadlo R. 
Published: January 2012

AbstractBACKGROUND:Ethical concerns about phase 1 trials persist. Important conceptual advances have been made in understanding concepts used to describe misunderstanding. However, a systematic, empirical evaluation of the frequency of misunderstanding incorporating recent developments is lacking.METHODS:The authors queried 95 participants in phase 1 trials to provide a more sophisticated estimate of the proportion who had therapeutic misconception (TM), defined as misunderstanding the research purpose or how research differs from individualized care, and therapeutic misestimation (TMis), defined as incorrectly estimating the chance of a research trial benefit as >20% or underestimating risk as 0%.RESULTS:Sixty‐five of 95 respondents (68.4%) had TM, which was associated in a multivariate analysis with lower education and family income (P = .008 and P = .001, respectively), but TM was not associated with the vulnerability of having hardly any treatment options. Eighty‐nine of 95 respondents (94%) had TMis, although only 18% reported this was a factual estimate. Although the risks of investigational agents and those exacerbated by research, such as uncertain outcomes, were mentioned (39% and 41% of respondents, respectively), risks novel to research, such as research biopsies, were rarely mentioned (3% of respondents). Although most of these respondents believed that their chance of benefit was greater and that their risk was lower than the population chance (optimists) (54.6%), a substantial minority of respondents (37.6%) were pessimists.CONCLUSIONS:TM continues to be prevalent. Estimates of personal benefit were not usually meant to report facts, it remains unknown whether respondents in the current study had TMis. Although they are not more vulnerable, phase 1 participants need improved understanding of key TM concepts, with attention to risks that are not present in standard of care. Cancer 2012. © 2012 American Cancer Society
Adenoid cystic carcinoma of the head and neck
Authors: Ellington Christopher L. , Goodman Michael , Kono Scott A. , Grist William , Wadsworth Trad , Chen Amy Y. , Owonikoko Taofeek , Ramalingam Suresh , Shin Dong M. , Khuri Fadlo R. , Beitler Jonathan J. , Saba Nabil F. 
Published: January 2012

AbstractBACKGROUND:Adenoid cystic carcinoma (ACC) of the head and neck (ACCHN) is a rare tumor of minor salivary, parotid, and submandibular glands. The biologic behavior of the disease is poorly understood, and nonsurgical treatment strategies have yet to be standardized. The long‐term prognosis continues to be guarded, with an estimated 10‐year survival of <60%. Population‐based studies examining ACC are scarce. The authors aimed to analyze incidence rates and survival outcomes for patients diagnosed with ACCHN using national population‐based data.METHODS:Data were obtained from the US National Cancer Institute's Surveillance, Epidemiology, and End Results (SEER) program. Newly diagnosed ACCHN cases reported to SEER from 1973 through 2007 were categorized according to their sex, race, age, year of diagnosis, marital status, treatment interventions, primary tumor site, and disease stage. Incidence of ACCHN and postdiagnosis survival were examined over time and compared across different demographic and disease‐related categories.RESULTS:The authors identified 3026 patients with ACCHN. The mean age at diagnosis among those cases was 57.4 years (range, 11‐99 years). Analyses of incidence data demonstrated a decline in ACCHN rates between 1973 and 2007, noted across all sexes and races with no detectable inflexion points. The overall 5‐year, 10‐year, and 15‐year survival outcomes for ACCHN patients were 90.3%, 79.9%, and 69.2%, respectively. Females, patients with localized disease, and younger patients were found to have significantly better survival across all time periods (all comparison‐specific log‐rank P values <0.001). Multivariate analyses revealed better prognosis among women compared with men (hazard ratio [HR], 0.73; 95% confidence interval [CI], 0.65‐0.82), among married compared with unmarried individuals (HR, 0.81; 95% CI, 0.71‐0.91), with certain sites of origin and stage of disease (HR, 2.788; 95% CI, 2.36‐3.29), and in those who had surgery of the primary tumor site (HR, 0.45; 95% CI, 0.37‐0.54).CONCLUSIONS:The overall incidence of ACC is declining. The noted differences in survival based on sex, marital status, site of origin, and treatment intervention require further investigation. Cancer 2012. © 2012 American Cancer Society
Comparison of adverse events during 5‐fluorouracil versus 5‐fluorouracil/oxaliplatin adjuvant chemotherapy for stage III colon cancer
Authors: Sanoff Hanna K. , Carpenter William R. , Freburger Janet , Li Ling , Chen Kun , Zullig Leah L. , Goldberg Richard M. , Schymura Maria J. , Schrag Deborah 
Published: January 2012

AbstractBACKGROUND:In clinical trials, combined 5‐fluorouracil (5FU) plus oxaliplatin improves the survival of patients who have resected, stage III colon cancer with manageable toxicity. However, the tolerability of this in the general population of patients with colon cancer is uncertain.METHODS:Adverse outcomes were compared in patients with stage III colon cancer who received either 5FU or 5FU/oxaliplatin within 120 days of undergoing resection versus a control group of patients with stage II colon cancer who did not receive chemotherapy in the Surveillance, Epidemiology, and End Results (SEER)‐Medicare database and in data from the New York State Cancer Registry linked to Medicare and Medicaid. Hospitalizations, emergency room (ER) visits, and outpatient adverse events (AEs) were measured in claims from 30 days to 9 months after patients underwent resection. Multiple logistic regression was used to calculate adjusted odds ratios of events by treatment. Propensity score matching was used to minimize selection bias.RESULTS:Adverse outcomes were more frequent for chemotherapy recipients. AE rates were higher in patients who received 5FU/oxaliplatin (81%) compared with patients who received 5FU alone (72%), in the SEER‐Medicare data. The effect of oxaliplatin on AEs was greater in older patients: The odds ratio was 2.10 (95% confidence interval, 1.53‐2.87) for patients aged ≥75 years versus 1.75 (95% confidence interval, 1.39‐2.21) for patients aged <75 years. ER use was high in Medicaid patients (83% of those who received chemotherapy), but neither ER use nor hospitalization was increased by oxaliplatin. The 60‐day mortality rate was 1% to 3% for patients who received 5FU alone and 1% to 2% for patients who received combined 5FU/oxaliplatin.CONCLUSIONS:The incremental harms of adjuvant chemotherapy with 5FU/oxaliplatin versus 5FU alone were modest in patients with stage III colon cancer who were insured by Medicare and Medicaid. The additional harms in patients aged ≥75 years largely were restricted to outpatient events and did not extend to an increased rate of hospitalization or early death. Cancer 2012. © 2012 American Cancer Society