bluuebunny/crossref_metadata_2025 huggingface dataset:
Downregulation and aberrant promoter methylation of p16INK4A: A possible novel heritable susceptibility marker to retinoblastoma
Authors: Indovina Paola , Acquaviva Antonio , De Falco Giulia , Rizzo Valeria , Onnis Anna , Luzzi Anna , Giorgi Francesca , Hadjistilianou Theodora , Toti Paolo , Tomei Valentina , Pentimalli Francesca , Carugi Alessandro , Giordano Antonio
Published: December 2009

RB loss has long been recognized as the causative genetic alteration underlying retinoblastoma but it is increasingly evident that other alterations are required for the tumor to develop. Therefore, we set out to identify additional inheritable susceptibility markers and new potential preventive and therapeutic targets for retinoblastoma. We focused on the p16INK4A tumor suppressor gene because of its possible role in retinoblastoma pathogenesis and its involvement in predisposition to familial cancer. p16INK4A expression was analyzed in tumor samples from retinoblastoma patients by immunohistochemistry and in peripheral blood cells from both patients and their parents by real‐time quantitative reverse transcription‐PCR (qRT‐PCR). Since promoter methylation is a common mechanism regulating p16INK4A expression, the methylation status of its promoter was also analyzed in blood samples from patients and their parents by methylation‐specific PCR. A downregulation of p16INK4A was observed in 55% of retinoblastoma patients. Interestingly, in 56% of the cases showing p16INK4A downregulation at least one of the patients' parents bore the same alteration in blood cells. Analysis of p16INK4A promoter methylation showed hypermethylation in most patients with p16INK4A downregulation and in the parents with the same alteration in p16INK4A expression. The finding that p16INK4A was downregulated both in patients and their parents suggests that this alteration could be a novel inheritable susceptibility marker to retinoblastoma. The observation that p16INK4A downregulation seems to be due to its promoter hypermethylation opens the way for the development of new preventive and therapeutic strategies using demethylating agents. J. Cell. Physiol. 223: 143–150, 2010. © 2009 Wiley‐Liss, Inc.
Integrated methodology for the evaluation of cleaning effectiveness in two Russian icons (16th–17th centuries)
Authors: Anca Sandu Irina Crina , Bracci Susanna , Lobefaro Mariella , Sandu Ion
Published: December 2009

This article covers a methodology for evaluating the effectiveness of cleaning two Russian icons. The icons belong to a group of five from the same iconographic school, dating from the 16th to 17th centuries. An integrated and complementary approach to varnish and overpaint removal involved microscopic techniques (optical and scanning electron microscopy) and colorimetry (CIE L*a*b* system). The materials and techniques used in these icons have been characterized previously. Cleaning revealed extensive overpainting that had not only dramatically changed the original appearance, but also the meaning and attribution of one of the two icons. The analyses carried out were useful in determining the extent of the overpainting and led to a better assessment of the results and effectiveness of the restoration. Microsc. Res. Tech. 73:752–760, 2010. © 2009 Wiley‐Liss, Inc.
How a heavy‐bodied snake strikes quickly: high‐power axial musculature in the puff adder (Bitis arietans)
Authors: Young Bruce A.
Published: December 2009

Despite being large, heavy‐bodied snakes, puff adders (Bitis arietans) are capable of achieving strike velocities and accelerations similar to, or greater than, those of much smaller snakes (means of 2.6 and 72 m/sec2, respectively). The mechanistic basis of the strike was examined using high‐speed digital videography, coupled with electromyographic (EMG) analysis, of the two main extensors of the vertebral column, the semispinalis and longissimus. Although the strike involves the rapid extension of preformed body curves, the extensor muscles were not electrically active during body extension. The vertebral extensor muscles exhibited bursts of electrical activity before the onset of movement—and quantified features of these EMG signals were significantly related to kinematic aspects of the strike (e.g., acceleration)—however, this electrical activity terminated shortly (∼50 msec) before the onset of movement. It is hypothesized that the prestrike activity of the extensor muscles functions to place the (extensive) musculo‐tendon complex of the snake's epaxial muscles under tension, and that the displacement of the body during the strike is due to the elastic recoil of this musculo‐tendon complex. Incorporation of this type of elastic recoil would increase the power output of the vertebral extensors. Power amplification of the vertebral extensors may be an evolutionary necessity if a large, heavy‐bodied snake, like B. arietans, is going to achieve rapid acceleration during the strike. J. Exp. Zool. 313A:114–121, 2010. © 2009 Wiley‐Liss, Inc.
Efficient synthesis of benzothieno[3,2‐d]‐imidazo[1,2‐a]pyrimidine‐2,5‐(1H, 3H)‐diones via a tandem aza‐wittig/heterocumulene‐mediated annulation
Authors: Xu Sheng‐Zhen , Wu Jing , Cao Min‐Hui , Ding Ming‐Wu
Published: December 2009

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Carbodiimide 2, obtained from aza‐Wittig reaction of iminophosphorane 1 with aromaic isocyanate, reacted with α‐amino ester in the presence of catalytic amount of sodium ethoxide to give selectively new tetracyclic benzothieno[3,2‐d]‐imidazo[1,2‐a]pyrimidine‐2,5‐(1H, 3H)‐diones 5 in good yields. X‐Ray structure analysis of 5b verified the proposed structure and the reaction selectivity. J. Heterocyclic Chem., 2010.
The anion binding properties bearing neutral cycle amine recognition sites
Authors: Shang Xuefang , Xu Xiufang
Published: December 2009

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O‐phenylene‐diamine derivative containing colorimetric dinitroquinoxaline has been synthesized. Its UV‐vis spectroscopy and 1H NMR investigation reveal that the receptor shows the strong binding ability for AcO−, F−, and H2PO, moderate binding abilities for OH− and almost no binding abilities for Cl−, Br−, and I−. The interaction of the receptor with studied anions achieving the recognition of anions is proposed to come from the NH…F and potential CH…F hydrogen bonding in its neutral form. The results indicate that it is well suitable for the anion complexation, which is presumably contributed to its ring topology possessing a rigidity conjugation system. Moreover, the molecular orbital level of this receptor and its tautomer were further determined by means of theoretical investigations. J. Heterocyclic Chem., 2010.
Regioselective synthesis of pyrimido[5,4‐c][2,1]benzothiazines by reactions of β‐chloroaldehydes with n‐c‐n binucleophiles
Authors: Popov Kirill , Volovnenko Tatyana , Turov Alexander , Volovenko Yulian
Published: December 2009

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The method of pyrimidine ring fusion at the [c] side of benzothiazines based on the reaction of their chloroaldehyde derivatives with amidines is described. Formation of the structural isomers of reaction products was investigated, and regioselectivity of heterocyclization reactions was shown. A number of novel pyrimidobenzothiazines were synthesized. J. Heterocyclic Chem., 2010.
A diagnostics approach to economic growth and employment policy in low income economies: The case of Kosovo
Authors: Sen Kunal , Kirkpatrick Colin
Published: December 2009

The economic challenges facing Kosovo in 2008 are considerable. Economic growth has been below the rate achieved in neighbouring countries and more than one‐third of the work force is unemployed. The paper applies a ‘diagnostics’ analytical framework to identify the most binding constraints on economic growth and job creation. The binding constraints to growth are found to be the costs and access to finance, poor provision of public goods and weaknesses in the rule of law. The analysis also suggests that policy options for job creation must focus on increasing both economic growth and the employment intensity of growth. Copyright © 2009 John Wiley & Sons, Ltd.
Ionizing radiation enhances tumor necrosis factor‐related apoptosis‐inducing ligand (TRAIL)‐induced apoptosis through up‐regulations of death receptor 4 (DR4) and death receptor 5 (DR5) in human osteosarcoma cells
Authors: Hori Takeshi , Kondo Takashi , Kanamori Masahiko , Tabuchi Yoshiaki , Ogawa Ryohei , Zhao Qing‐Li , Ahmed Kanwal , Yasuda Taketoshi , Seki Shoji , Suzuki Kayo , Kimura Tomoatsu
Published: December 2009

Despite improvements in chemotherapy and surgery in the treatment of osteosarcoma (OS), satisfactory results are still difficult to achieve. Novel therapeutic modalities need to be developed for osteosarcoma treatment. The combined effects of tumor necrosis factor‐related apoptosis‐inducing ligand (TRAIL) and ionizing radiation (IR) on human OS cells were investigated. IR and TRAIL treatment synergistically decreased the cell viability and enhanced apoptosis in OS cell lines. IR pretreatment enhances TRAIL‐induced Bid and caspase‐3 activations. Decreases in the expression levels of the antiapoptotic proteins c‐FLIP and XIAP also associated with apoptosis enhancement. Furthermore, IR pretreatment enhanced DR4 and DR5 expressions at the transcription stage. These results can become the basic lines of evidence for the future treatment of OS using TRAIL with IR. © 2009 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 28:739–745, 2010
Chondrogenic differentiation of human subchondral progenitor cells is impaired by rheumatoid arthritis synovial fluid
Authors: Krüger Jan Philipp , Endres Michaela , Neumann Katja , Häupl Thomas , Erggelet Christoph , Kaps Christian
Published: December 2009

In microfracture, subchondral progenitors enter the cartilage defect and form cartilage repair tissue. We hypothesize that synovial fluid (SF) from rheumatoid arthritis (RA) donors affects chondrogenesis of human subchondral progenitors stimulated with transforming growth factor‐β3 (TGFB3), whereas SF from normal and osteoarthritis (OA) donors do not. Human progenitors from subchondral cortico‐spongious bone (pool of n = 4) were cultured in micromasses under serum‐free conditions and were stimulated with 10 ng/mL TGFB3 and with 5% SF from normal, OA, and RA donors (pool of n = 7, each). Histological staining of proteoglycan and immunostaining of type II collagen showed that progenitors stimulated with SF from RA donors show significantly reduced cartilage matrix formation compared to progenitors treated with TGFB3 or with SF from normal and OA donors (n = 3, each). Gene expression analysis of typical chondrocyte marker genes and genes encoding matrix modifying enzymes showed that SF from OA and RA donors influence the onset of TGFB3‐mediated chondrogenesis (pool of 20 micromasses), but had no effect on the gene expression profile after prolonged culture in micromasses. These results suggest that SF from RA patients may impair the chondrogenic development of mesenchymal progenitors in microfracture, whereas osteoarthritic SF may has no negative effect on the cartilage matrix formation. © 2009 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 28:819–827, 2010
Action of IL‐1β during fracture healing
Authors: Lange Jeffrey , Sapozhnikova Anna , Lu Chuanyong , Hu Diane , Li Xin , Miclau Theodore , Marcucio Ralph S.
Published: December 2009

After bone injury, developmental processes such as endochondral and intramembranous ossification are recapitulated as the skeleton regenerates. In contrast to development, skeletal healing involves inflammation. During the early stages of healing a variety of inflammatory cells infiltrate the injured site, debride the wound, and stimulate the repair process. Little is known about the inflammatory process during bone repair. In this work, we examined the effect of a pro‐inflammatory cytokine, Interleukin‐1 beta (IL‐1β), on osteoblast and stem cell differentiation and on intramembranous and endochondral ossification, because IL‐1β exerts effects on skeletal homeostasis and is upregulated in response to fracture. We determined that IL‐1β stimulated proliferation of osteoblasts and production of mineralized bone matrix, but suppressed proliferation and inhibited differentiation of bone marrow derived MSCs. We next performed loss‐ and gain‐of‐function experiments to determine if altering IL‐1β signaling affects fracture healing. We did not detect any differences in callus, cartilage, and bone matrix production during healing of nonstabilized or stabilized fractures in mice that lacked the IL‐1β receptor compared to wild‐type animals. We observed subtle alterations in the healing process after administering IL‐1β during the early phases of repair. At day 10 after injury, the ratio of cartilage to callus was increased, and by day 14, the proportion of cartilage to total callus and to bone was reduced. These changes could reflect a slight acceleration of endochondral ossification, or direct effects on cartilage and bone formation. © 2009 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 28:778–784, 2010
Mapping the human record in the British early Palaeolithic: evidence from the Solent River system
Authors: Ashton Nick , Hosfield Rob
Published: December 2009

The lithic record from the Solent River and its tributaries is re‐examined in the light of recent interpretations about the changing demography of Britain during the Lower and early Middle Palaeolithic. Existing models of the terrace stratigraphies in the Solent and its tributary areas are reviewed and the corresponding archaeological record (specifically handaxes) for each terrace is assessed to provide models for the relative changes in human occupation through time. The Bournemouth area is studied in detail to examine the effects of quarrying and urbanisation on collection history and on the biases it introduces to the record. In addition, the effects of reworking of artefacts from higher into lower terraces are assessed, and shown to be a significant problem. Although there is very little absolute dating available for the Solent area, a cautious interpretation of the results from these analyses would suggest a pre‐Marine Isotope Stage (MIS) 12 date for the first appearance of humans, a peak in population between MIS 12 and 10, and a decline in population during MIS 9 and 8. Owing to poor contextual data and small sample sizes, it is not clear when Levallois technology was introduced. This record is compared and contrasted to that from the Thames Valley. It is suggested that changes in the palaeogeography of Britain, in particular land connections to the continent, might have contributed to differences in the archaeological records from the Solent and Thames regions. Copyright © 2009 John Wiley & Sons, Ltd.
Lake‐level changes in central Patagonia (Argentina): crossing environmental thresholds for Lateglacial and Holocene human occupation
Authors: Ariztegui Daniel , Gilli Adrian , Anselmetti Flavio S. , Goñi Rafael A. , Belardi Juan B. , Espinosa Silvana
Published: December 2009

The role and extent of climate as a cause of the expansion and decline of human cultures is still debatable. It is clear, however, that human–environment interactions are enhanced and interplay more closely in climatically sensitive areas such as around hydrologically closed basins. Lago Cardiel is located at 49° S in the very arid rain shadow east of the Andes, providing an exceptionally receptive system to changes in hydrological balance. Results of a geophysical survey combined with sedimentological and geochemical studies provide a continuous Lateglacial–Holocene record of substantial water‐level changes. These variations, combined with archaeological results from the catchment area, offer a unique possibility to explore the pattern of peopling within this remote area of the globe and its possible relation to climate change. Human occupation in Patagonia is well documented towards the Andes throughout the entire Holocene. Archaeological data from the Lago Cardiel basin, however, show an apparent lack of human activity during the first part of this period, which coincides with well‐constrained high lake levels. Our results show an intriguing coincidence between low lake level and increasing human occupation, suggesting that the Lago Cardiel basin has focused human use during intervals with relatively lower effective moisture such as during the Late Pleistocene, but its evidence may have been submerged. This interpretation is confirmed by archaeological remains from Lago Strobel, another perennial lake with a comparable catchment located in the same climatic region and thus sharing the same climatic history as Lago Cardiel. Copyright © 2009 John Wiley & Sons, Ltd.
Prostate stem cell antigen mRNA in peripheral blood as a potential predictor of biochemical recurrence in high‐risk prostate cancer
Authors: Joung Jae Young , Cho Kang Su , Kim Jeong Eun , Seo Ho Kyung , Chung Jinsoo , Park Weon Seo , Choi Moon Kyong , Lee Kang Hyun
Published: December 2009

Objective

To determine whether the presence of prostate stem cell antigen (PSCA) mRNA in peripheral blood can predict biochemical recurrence (BCR) after radical prostatectomy in patients with high‐risk prostate cancer.

Methods

High‐risk disease was defined based on the presence of any one of the following three risk factors: prostate‐specific antigen (PSA) ≥20 ng/ml, a biopsy Gleason score (GS) ≥8, or clinical stage ≥T2c. Nested reverse transcriptase‐polymerase chain reaction (RT‐PCR) was employed to detect PSCA mRNA‐bearing cells in peripheral blood. The relationship between PSCA detection and BCR after surgery was evaluated.

Results

Of the 250 patients, 103 (36.8%) with high‐risk disease were included in the analysis. PSCA‐mRNA was detected in 17 (16.5%) of these patients. Patients with high GS (≥7) tended to be PSCA‐mRNA positive status (P = 0.045). Over a median 23 months of follow‐up (range 3–47 months), BCR developed in 27 patients (26.2%). Cox regression hazards model analysis revealed that a RT‐PCR PSCA positivity (HR, 4.549; 95%CI, 1.685–12.279; P = 0.003) independently increased the risk of BCR.

Conclusions

The presence of PSCA mRNA in peripheral blood is a significant predictor of BCR after radical prostatectomy in high‐risk prostate cancer. J. Surg. Oncol. 2010;101:145–148. © 2009 Wiley‐Liss, Inc.
SCRN1 is a novel marker for prognosis in colorectal cancer
Authors: Miyoshi Norikatsu , Ishii Hideshi , Mimori Koshi , Sekimoto Mitsugu , Doki Yuichiro , Mori Masaki
Published: December 2009

Purpose

Secernin 1 (SCRN1) is a member of the secernin family and is reported to be a tumor‐associated antigen. Previous reports show that SCRN1 is upregulated in gastric cancer cell lines and may be a novel immunotherapy target, whereas its significance in colorectal cancer (CRC) is not fully understood.

Materials and Methods

The present study comprised 54 patients who underwent surgery for CRC, as well as two cell lines derived from human CRC. We assessed the correlation of gene expression with clinical parameters in the CRC patients, and knockdown was evaluated in the cell lines.

Results

Thirty of the 54 (55.5%) cases exhibited a higher expression of the SCRN1 gene in cancerous regions than marginal non‐cancerous regions. Patients with high SCRN1 expression were statistically susceptible to a poor prognosis and showed poorer disease‐free survival than those with low expression. SCRN1 knockdown in the two cell lines demonstrated that the siRNA inhibition resulted in a statistically significant reduction in cell growth.

Conclusion

The present data strongly suggest that SCRN1 expression is a prognostic factor in CRC patients. J. Surg. Oncol. 2010;101:156–159. © 2009 Wiley‐Liss, Inc.
Metalloproteinases and their regulators in colorectal cancer
Authors: van der Jagt Michel F.P. , Wobbes Theo , Strobbe Luc J.A. , Sweep Fred C.G.J. , Span Paul N.
Published: December 2009

Metalloproteinases (MPs) such as the matrix metalloproteinases (MMPs) and adamalysins (ADAMs and ADAMTS) are expressed in various stages of colorectal cancer (CRC), and some correlate with survival and prognosis. The MPs are regulated by various factors including EMMPRIN, TIMPs, and RECK. In addition, micro‐RNAs are found to be relevant for both MP expression levels and CRC prognostication. Both MPs and their regulators could be potential targets for intervention and therapy in CRC. J. Surg. Oncol. 2010; 101:259–269. © 2009 Wiley‐Liss, Inc.
Determination of volatile organic acids in tobacco by single‐drop microextraction with in‐syringe derivatization followed by GC‐MS
Authors: Sha Yunfei , Meng Jiaoran , Zhang Yichun , Deng Chunhui , Wu Da
Published: December 2009

In this work, the novel technique based on headspace single‐drop microextraction with in‐syringe derivatization followed by GC‐MS was established to determine the volatile organic acids in tobacco. The parameters for headspace single‐drop microextraction and in‐syringe derivatization were optimized, including extraction time, and volume of derivatization reagent and in‐syringe derivatization time. The method validations including linearity, precision, recovery and LOD were also studied. The obtained results illustrated that the optimized technique was easy, highly efficient and sensitive. Finally, the proposed method was successfully applied to the analyses of volatile organic acids in tobacco samples with seven different brands. It was further demonstrated that the present technique developed in this study does offer a simple and fast approach to determine volatile organic acids in tobacco.
Development and optimization of the SPE procedure for determination of pharmaceuticals in water samples by HPLC‐diode array detection
Authors: Mutavdžić Pavlović Dragana , Babić Sandra , Dolar Davor , Ašperger Danijela , Košutić Krešimir , Horvat Alka J. M. , Kaštelan‐Macan Marija
Published: December 2009

This paper focuses on the investigation of different types of SPE sorbents for the preconcentration of eight veterinary pharmaceuticals from water samples. The pharmaceuticals studied were sulfamethazine, sulfadiazine, sulfaguanidine, trimethoprim, oxytetracycline, enrofloxacin, norfloxacin and penicillin G/procaine. Five different SPE materials (Strata‐X, Strata‐X‐C, Strata SDB‐L, Strata C8 and Strata C18) from Phenomenex were compared with Oasis HLB with a view to obtaining the best cartridges for all pharmaceuticals investigated. Extraction efficiency was determined by HPLC with diode array detection (DAD). HPLC‐DAD separation and quantification of the selected pharmaceuticals were carried out under gradient elution by a binary mixture of 0.01 M oxalic acid and ACN based on cyano modified column (LiChrosphere 100 CN) from Merck. Strata‐X provided the best results in the preconcentration of 100 mL water samples, yielding average pharmaceutical recoveries of higher than 90%, except for sulfaguanidine (76.1%). The developed Strata‐X‐HLPC‐DAD method was validated and applied, for the efficient investigation of reverse osmosis/nanofiltration membranes and for the removal of these eight pharmaceuticals from the production wastewater samples. NF90 and XLE membranes were shown to be the best for the rejection of all investigated pharmaceuticals.
Extraction of organophosphorus pesticides in water and juice using ultrasound‐assisted emulsification–mixroextraction
Authors: Jia Chunhong , Zhu Xiaodan , Chen Li , He Min , Yu Pingzhong , Zhao Ercheng
Published: December 2009

In this study, a microextraction method termed as ultrasound‐assisted emulsification–microextraction (USAEME) has been developed for the extraction of organophosphorus pesticides (OPPs) in water and orange juice samples. In the USAEME method, aliquots of 50 μL chlorobenzene used as extraction solvent was added to 10 mL water sample in a conical glass centrifugal tube. Factors influencing the USAEME extraction efficiency such as sonication time, extraction solvent, extraction volume and salt addition were evaluated. Under the optimum conditions, enrichment factors ranged from 241 to 311, LOD varied from 5.3 to 10.0 ng/L and linearity with a coefficient of estimation (r2) varied from 0.9991 to 0.9998 in the concentration level range of 0.05–2.5 μg/L for the extraction of OPPs in water samples. Finally, the proposed USAEME method was used for the extraction of OPPs from water and orange juice. The recoveries were in the range of 80.0–110.0%, and the repeatability of the method expressed as RSD (n=3) varied between 1.6 and 13%. The USAEME method has the advantage of being easy to operate, low consumption of organic solvent and high extraction efficiency.
LC‐MS identification of derivatized free fatty acids from adipocere in soil samples
Authors: Algarra Manuel , Rodríguez‐Borges José E. , Esteves da Silva Joaquim C. G.
Published: December 2009

Free fatty acids were derivatized as amides (DFFA) by reaction with (R)‐(+)‐1‐phenylethylamine, using a simple, fast and robust reaction scheme. A HPLC method with diode array and ESI MS detection was developed for the analysis of the derivatized substances. Six fatty acids were used in the method development: myristic, linoleic, palmitic, oleic, margaric and stearic acids. Under these conditions the elution of the DFFA are well resolved with retention times raging from 6.9 to 16.0 min. Fatty acids were extracted from cemetery soil and from adipocere formation experimental soils using a Soxhlet extraction, using as solvent ether/dichloromethane (1:1). Each DFFA is characterized by three m/z peaks: molecular weight of the substance; molecular weight of a dimer of the substance; the molecular weight of the dimer plus the atomic mass of sodium. The analysis of soil samples detected the six fatty acids used in the method developed plus palmitoleic and pentadecanoic. Beside this set of eight fatty acids other 13 fatty acids were detected in trace quantities or only in some soils and some were tentatively assigned as: 10‐hydroxystearic, myristoleic, heptadecenoic and arachidic acids.
Five keys to flourishing in trying times
Authors: Cameron Kim
Published: December 2009

Kim Cameron reports on two decades of empirical research on organizations that have faced difficult economic situations but achieved unexpected and exceptional levels of success. Examining these organizations, Cameron has uncovered some unusual leadership strategies that can serve as guidelines for organizations facing trying times. These strategies focus on the positive, or an orientation toward strengths rather than weaknesses and abundance rather than deficits in organizations. Cameron explains why these strategies succeed and offers five critical guidelines on putting them to use in your organization.
Polyethylene Prodrugs Using Precisely Placed Pharmaceutical Agents
Authors: Leonard James K. , Turek Diane , Sloan Kenneth B. , Wagener Kenneth B.
Published: December 2009

Polyethylene‐based polymeric prodrugs have been prepared by acyclic diene metathesis (ADMET) polymerization; this condensation type, step growth polymerization, affords controlled polymer architectures via exact methylene run lengths between drug branches. Polyethylene was synthesized with the nonsteroidal anti‐inflammatory drug (NSAID) branches ibuprofen and naproxen attached at every 21st backbone carbon through a hydrolysable ester linkage. These ester linkages can have their reactivity tuned by using a variety of spacers that link the drug to the polymer backbone. Two types of spacers, tetraethylene glycol (TEG, hydrophilic) and decanediol (hydrophobic), were incorporated between the drugs and the polymer backbone to observe the effect of spacer properties on the rate of drug release. The rate of hydrolysis and subsequent release of drug was monitored as a direct effect of the spacer and type of reactive linker. With the primary structure of the polymers perfectly known, making such subtle changes to these structures has a dramatic influence on their physical properties. The polymers discussed herein are characterized with NMR, IR, TGA, and DSC. The rate at which these materials hydrolyze and release their pharmaceutical species via enzymatic or chemical hydrolysis was monitored by UV‐vis. Tailoring the type of spacer and hydrolysable linker to a particular drug offers a new class of polyethylene with controllable features that can be used in the application of a new drug delivery material.

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Synthesis and Characterization of Polystyrene with DBS Networks
Authors: Lai Wei‐Chi , Lai Po‐Hsiang
Published: December 2009

Novel polystyrene (PS) materials were prepared through thermally initiated polymerization in the presence of 1,3:2,4‐dibenzylidene‐D‐sorbitol (DBS) organogels. The organogels were the result of the formation of DBS nanofibrillar networks. The effects of the DBS amounts on the polymerization rate, molecular weight, swelling ratio, and thermal properties of the PS samples were investigated. The increase in the DBS content increased the polymerization rate and molecular weight. The swelling ratio experiment demonstrated the cross‐linking density of the PS sample increased as the DBS amount was increased. In addition, the glass transition temperature increased with the DBS content. Thermogravimetric analysis results showed the thermal decomposition temperature was not affected by the addition of DBS.

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Electrochemically Induced RAFT Polymerization of Thermoresponsive Hydrogel Films: Impact on Film Thickness and Surface Morphology
Authors: Bünsow Johanna , Mänz Martin , Vana Philipp , Johannsmann Diethelm
Published: December 2009

Thin hydrogel films of the thermoresponsive polymer poly(N‐isopropylacrylamide) (pNIPAm) were prepared by electrochemically triggered reversible addition‐fragmentation chain transfer (RAFT) polymerization. Two different RAFT agents were employed, which work in either acidic or basic solution. In both cases, addition of RAFT agents had an influence on the thickness and the surface morphology of the films. At low concentration, the polymerization efficiency increased. At high concentration, the efficiency decreased at acidic pH, while it remained constant under basic conditions. Neither RAFT agent displayed electrochemical activity on its own, but they did modify the electrochemical behavior of the initiator. The addition of RAFT agent strongly enhances the homogeneity of the hydrogel surfaces, which presumably is due to a reduced amount of microgel formation.

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Solid‐State Synthesis of Silver Nanoparticles at Room Temperature: Poly(vinylpyrrolidone) as a Tool
Authors: Debnath Dipen , Kim Chorong , Kim Sung H. , Geckeler Kurt E.
Published: December 2009

Silver nanoparticles have been used for a long time and recently various methods have been additionally developed for their production. Here we report for the first time a solid‐state high‐speed vibration milling method for the synthesis of silver nanoparticles, in which poly(vinylpyrrolidone) is used for the reduction of the silver salt. The synthesis is performed at room temperature and no surfactant to direct the anisotropic growth of the nanoparticles is required. The formation of the nanoparticles was studied by UV–Visible spectroscopy, transmission electron microscopy, and powder X‐ray diffraction techniques. The nanoparticles synthesized were found to be uniform in size and shape with an average diameter of less than 5 nm. In addition, the antimicrobial activity of these silver nanoparticles was investigated against Escherichia coli and found to be positive.

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How are prices adjusted in response to shocks? Survey evidence from Austrian firms
Authors: Kwapil Claudia , Scharler Johann , Baumgartner Josef
Published: December 2009

In this paper we investigate the response of prices to shocks based on a survey of Austrian firms. We find that firms are more likely to change prices after a cost shock than after a demand shock. In this vein, our analysis suggests that regular customers are an important explanation for price rigidity after demand shocks. Furthermore, lacking competition is another significant explanation for price stickiness. Finally, we find asymmetric responses after cost and demand shocks. Prices appear to be more rigid downward than upward after cost shocks, while they are more rigid upward than downward in reaction to shifts in demand. Copyright © 2009 John Wiley & Sons, Ltd.
Evidence on competitive advantage and superior stock market performance
Authors: Gjerde Øystein , Knivsflå Kjell , Sættem Frode
Published: December 2009

This article analyzes the value‐relevance of industry‐based and resource‐based competitive advantage in a large sample of firms listed on the Oslo Stock Exchange. We measure competitive advantage by a single variable and perform a new decomposition into its underlying sources. In 1986–2005, the industry‐based and the resource‐based competitive advantage explain more than 20% of abnormal stock market returns, accumulated over 5 years. The resource‐based advantage is almost 4 times more important than the industry‐based advantage. Differences in both the return and the risk capability of firms' net assets relative to their industry peers are significant parts of the resource‐based advantage, estimated at 60 and 40%, respectively. Copyright © 2009 John Wiley & Sons, Ltd.
The Japanese toxicogenomics project: Application of toxicogenomics
Authors: Uehara Takeki , Ono Atsushi , Maruyama Toshiyuki , Kato Ikuo , Yamada Hiroshi , Ohno Yasuo , Urushidani Tetsuro
Published: December 2009

Biotechnology advances have provided novel methods for the risk assessment of chemicals. The application of microarray technologies to toxicology, known as toxicogenomics, is becoming an accepted approach for identifying chemicals with potential safety problems. Gene expression profiling is expected to identify the mechanisms that underlie the potential toxicity of chemicals. This technology has also been applied to identify biomarkers of toxicity to predict potential hazardous chemicals. Ultimately, toxicogenomics is expected to aid in risk assessment. The following discussion explores potential applications and features of the Japanese Toxicogenomics Project.
Thermal and crystallization behavior of cotton—Polypropylene commingled composite systems
Authors: Jose E. Tomlal , Joseph Aju , Skrifvars Mikael , Thomas Sabu , Joseph Kuruvilla
Published: December 2009

Techniques like thermogravimetric analysis, differential scanning calorimetry, and polarized optical microscopy were used to study the thermal and crystallization behavior of cotton‐polypropylene (PP) commingled composite system. Thermal analysis was used to understand the structure‐property relationship and also to quantify the amount of moisture and volatiles, which causes the deterioration of the composite performance. Thermal stability of the composite was found be intermediate between that of PP and cotton fibers. Presence of treated reinforcements had increased the crystallinity of PP. Also, fibers act as heterogeneous nucleants and favor the early crystallization of PP in the composites. The crystallization and onset crystallization temperature values were increased by the presence of cotton fibers. The theories of heterogeneous nucleation and crystal growth kinetics were used to explain the growth of transcrystalline layer (TCL) of PP on cotton fibers. The interfacial free energy difference for nucleation of PP on fiber was found to be smaller compared with that in the bulk PP. This favors the formation and growth of TCL. The thickness of TCL and radius of the spherulites increase with the increase in the crystallization temperature. Fiber surface roughness and thermal stresses facilitate the growth of transcrystallinity on cotton fiber. POLYM. COMPOS., 31:1487–1494, 2010. © 2009 Society of Plastics Engineers
Film formation of nano‐sized hard latex (PS) in soft polymer matrix (PBA): An excimer study
Authors: Uğur Şaziye , Sunay Selin , Pekcan Önder
Published: December 2009

This work reports steady state fluorescence (SSF) technique for studying film formation from pyrene (P)‐labeled nano‐sized polystyrene (PS) and poly(n‐butyl acrylate) (PBA) hard/soft latex blends. Blend films were prepared from mixtures of PS and PBA in dispersion. Eight different blend films were prepared in various hard/soft latex compositions at room temperature and annealed at elevated temperatures above glass transition temperature (Tg) of polystyerene. Monomer (IP) and excimer (IE) intensities from P was measured after each annealing step to monitor the stages of film formation. The evolution of transparency of latex films was monitored using photon transmission intensity, Itr. Film morphologies were examined by atomic force microscopy (AFM). The results showed that as the amount of hard component (PS) in the blend is decreased, a significant change occurred in both IE/IP and Itr curves at a certain critical weight fraction (50 wt%) of PS hard latex. Two distinct film formation stages, which are named as void closure and interdiffusion were seen in (IE/IP) data above this fraction. However, below 50 wt% PS no film formation was observed. AFM pictures also confirmed these findings. Void closure and interdiffusion stages for (50–100) wt% range of PS were modeled and related activation energies were determined. There was no observable change in activation energies confirming that film formation behavior is not affected by varying the blend composition in this range. POLYM. COMPOS., 31:1611–1619, 2010. © 2009 Society of Plastics Engineers
Ultrasonochemical‐assisted fabrication and evaporation‐ induced self‐assembly (EISA) of POSS‐SiO2@Ag core/ABA triblock copolymer nanocomposite film
Authors: Veerapandian Murugan , Yun Kyusik
Published: December 2009

Poly(ethylene glycol)‐octafunctionalized polyhedral oligomeric silsesquioxane (POSS) (Mn = 5576.6 g/mol) alloying agent stabilized amphiphilic silica@silver metalloid nanocomposite blended with a triblock copolymer poly(p‐dioxanone‐co‐caprolactone)‐block‐poly(ethylene oxide)‐block‐poly(p‐dioxanone‐co‐caprolactone) (POSS‐SiO2@Ag/PPDO‐co‐PCL‐b‐PEG‐b‐PPDO‐co‐PCL) has been synthesized in both water and in organic medium utilizing ultrasonochemical reaction. The POSS stabilized pre‐made metalloid was successfully dispersed in amphiphilic PPDO‐co‐PCL‐b‐PEG‐b‐PPDO‐co‐PCL (ABA) triblock copolymer matrix of molecular weight 45.9 × 104 g/mol. The mechanism of synthesis of high concentration of SiO2@Ag nanocomposite from TEOS/AgNO3 (in the presence of NH4OH as catalyst/NaBH4 as reductant) nonmetal/metal precursors and the successful EISA of POSS‐SiO2@Ag/ABA nanocomposite into films has been discussed. The successful synthesis of metalloid nanocomposite was morphologically accessed by field emission‐scanning electron microscopy, transmission electron microscopy and atomic force microscopy. Surface plasmon resonance was ensured from UV–visible spectral analysis. Identity and the crystallinity of as prepared nanocomposite were studied by X‐ray diffractometer. Structural and luminescence properties of the nanocomposite were examined by Fourier transform infrared spectroscopy and photoluminescence. Thermogravimetric analysis was carried out to study the thermal stability of the resulting hybrid nanocomposite. The resultant inorganic–organic nanocomposite can be easily suspended in water and would be useful in variety of applications. POLYM. COMPOS., 31:1620–1627, 2010. © 2009 Society of Plastics Engineers
Twin‐to‐twin transfusion syndrome presenting at early stages: is there still a possible role for amnioreduction?
Authors: Fichera Anna , Lanna Mariano , Fratelli Nicola , Rustico Mariangela , Frusca Tiziana
Published: December 2009

Objective

To assess the rate of resolution or progression after first line treatment with amnioreduction and related outcome of pregnancies with twin‐to‐twin transfusion syndrome (TTTS) diagnosed at stages I‐II.

Method

Data on 34 monochorionic diamniotic twin pregnancies presenting with TTTS at stage I‐II before 26 weeks of gestation were collected retrospectively (1999–2006). All patients underwent at least one amnioreduction. The outcome and the results of neurological follow‐up of surviving twins were analysed in relation to the regression or progression of the disease after treatment.

Results

Fourteen cases (41%) resolved after treatment while 18 cases (53%) progressed. In two patients immediate complications occurred within one week after amnioreduction; at least one infant survived in 85.3% of cases and there was double survival in 58.8%. Double survival was significantly better in cases that regressed (85.7%) compared with those cases that progressed (44.4%). None of the surviving infants in the group of cases with regression showed major neurological abnormalities.

Conclusion

In our study, one‐third of patients with stage I‐II TTTS regressed after a single amnioreduction, and pregnancies with resolution of TTTS usually had a favourable outcome. Copyright © 2009 John Wiley & Sons, Ltd.
Silicone‐polyacrylate chemical compatibilization with organosilanes
Authors: dos Anjos Débora S.C. , Revoredo Eliane C.V. , Galembeck André
Published: December 2009

Silicone‐polyacrylate polymer blends were prepared using methacryloxy‐propyl‐trimethoxysilane (MAPTMS) as a compatibilizing agent (chemical linker). Energy dispersive X‐ray spectroscopy elemental mapping showed silicon and carbon rich regions corresponding to poly(dimethyl‐siloxane) (PDMS) and poly(methyl methacrylate) PMMA domains. Infrared spectroscopy confirmed that covalent bonds are formed between PMMA and the organosilane, MAPTMS. The organosilane addition decreased the water‐to‐blend contact angles and tended to increase the modulus of elasticity and tensile strength of the resulting PDMS‐PMMA blends. Cytotoxicity was not detectable for any samples. Silicone‐based materials are currently used as prosthetic materials to replace damaged tissues; the methodology described here can be readily adapted to this application with improved performance. POLYM. ENG. SCI., 2010. © 2009 Society of Plastics Engineers
Influence of phase morphology on the sliding wear of polyethylene blends filled with carbon nanofibers
Authors: Wood Weston , Li Bin , Zhong Wei‐Hong
Published: December 2009

In this work, phase separation in carbon nanofiber (CNF) composites with a blend of ultrahigh molecular weight polyethylene (UHMWPE)/high‐density polyethylene (HDPE) was revealed, and its effects on tribological properties were investigated. Results from morphological analysis by optical and scanning electron microscopy indicated two distinct microstructures: a dispersed UHMWPE phase and a continuous microstructure containing HDPE and CNFs. The addition of CNFs into the UHMWPE/HDPE blend induced a decreased steady‐state torque indicative of a decreased dissolution and improved processability. Because CNFs predominantly resided into the HDPE phase, neat HDPE, a HDPE/CNF composite, and neat UHMWPE samples were also prepared for comparison. Wear results, determined by a pin‐on‐disk apparatus, showed that both initial run‐in and steady‐state wear rates of the UHMWPE/HDPE/CNF nanocomposites were reduced with an increasing concentration of CNFs. The wear resistance of the UHMWPE/HDPE blend was more strongly influenced than neat HDPE by the addition of CNFs, which may have been affected by a reduced dissolution and improved interfacial interaction between the two phases. Results from this study suggested that HDPE may not be appropriate for processing UHMWPE composites, as CNFs reside in the HDPE phase, and HDPE diminishes the wear resistance of the material. POLYM. ENG. SCI., 2010. © 2009 Society of Plastics Engineers
Preparation and characterization of transparent PANI‐SIO2 hybrid conducting films
Authors: Wei Li , Chen Qi , Gu Yingjun
Published: December 2009

Dodecylbenzene sulfonic acid‐doped polyaniline (DBSA‐PANI) was prepared with 3‐glycidoxypropyltrimethoxysilane (GPTMS) through a sol–gel route without water and ethanol. Acetic acid was used to play both the roles of reagent and catalyst during the hydrolysis‐condensation reaction of GPTMS, which affected the structure of precursors. On the other hand, m‐cresol can adjust the acidity of solution and it was also a secondary dopant in DBSA‐PANI to enhance conductivity of hybrid films. The conductivity and visible light transmittance vary with the molar ratio of acetic acid to GPTMS and m‐cresol to GPTMS. Sheet resistance of the new hybrid films made by a dipping process reaches 5.1 kΩ/□ and visible light transmittance is higher than 75%. POLYM. ENG. SCI., 2010. © 2009 Society of Plastics Engineers
Rheology and extrusion foaming of chain‐branched poly(lactic acid)
Authors: Mihai Mihaela , Huneault Michel A. , Favis Basil D.
Published: December 2009

In this study, the effect of macromolecular chain‐branching on poly(lactic acid) (PLA) rheology, crystallization, and extrusion foaming was investigated. Two PLA grades, an amorphous and a semi‐crystalline one, were branched using a multifunctional styrene‐acrylic‐epoxy copolymer. The branching of PLA and its foaming were achieved in one‐step extrusion process. Carbon dioxide (CO2), in concentration up to 9%, was used as expansion agent to obtain foams from the two PLA branched using chain‐extender contents up to 2%. The foams were investigated with respect to their shear and elongational behavior, crystallinity, morphology, and density. The addition of the chain‐extender led to an increase in complex viscosity, elasticity, elongational viscosity, and in the manifestation of the strain‐hardening phenomena. Low‐density foams were obtained at 5–9% CO2for semi‐crystalline PLA and only at 9% CO2in the case of the amorphous PLA. Differences in foaming behavior were attributed to crystallites formation during the foaming process. The rheological and structural changes associated with PLA chain‐extension lowered the achieved crystallinity but slightly improved the foamability at low CO2content. POLYM. ENG. SCI., 2010. © 2009 Society of Plastics Engineers
Synthesis and characterization of poly(butyl acrylate‐co‐ethylhexyl acrylate)/ poly(vinyl chloride)[P(BA‐EHA)/PVC] novel core‐shell modifier and its impact modification for a poly(vinyl chloride)‐based blend
Authors: Pan Mingwang , Xing Shengnan , Yuan Jinfeng , Wu Jiawei , Zhang Liucheng
Published: December 2009

Synthesis of poly(butyl acrylate‐co‐ethylhexyl acrylate)‐core/poly(vinyl chloride)‐shell [P(BA‐EHA)/PVC] used as a modifying agent of PVC via semicontinuous seeded emulsion copolymerization is reported here. Diameter distributions and morphology of the composite latex particles were characterized with the aid of particle size analyzer and transmission electron microscopy (TEM). The grafting efficiency (GE) and grafting ratio (GR) of vinyl chloride (VC) grafted onto the P(BA‐EHA) with varying content of crosslinking agent and core‐shell ratios were investigated. TEM studies indicated that the P(BA‐EHA)/PVC latex particles have core‐shell structure, and the P(BA‐EHA) rubbery particles in blending materials were uniformly dispersed in PVC matrix. Dynamic mechanical analysis (DMA) results revealed that the compatibility between the P(BA‐EHA) and the PVC matrix was significantly improved due to the presence of the P(BA‐EHA)‐grafted‐VC copolymer. The notched impact strength of the blending material with 3 wt% of rubber content was seven times that of the PVC. Linear regressions of mechanical properties as loading of the modifier were made. The resulting data of notched impact strength and elongation at break for the blending materials deviated significantly from regression lines within 3–4.5 wt% of the P(BA‐EHA) content. The PVC blends modified by the modifier exhibited good toughness and easy processability. POLYM. ENG. SCI., 2010. © 2009 Society of Plastics Engineers