bluuebunny/crossref_metadata_2025_split huggingface dataset:
Synthesis and characterization of materials prepared via the copolymerization of ethylene with 1‐octadecene and norbornene using a [(π‐cyano‐nacnac)Cp] zirconium complex
Authors: Cabrera Alan R. , Schneider Yanika , Valderrama Mauricio , Galland Griselda B. , Rojas Rene S. 
Published: February 2011

Abstract[3‐Cyano‐2‐(2,6‐diisopropylphenyl)aminopent‐2‐en‐4‐(phenylimine)tris (pentafluorophenyl)borate](η5‐C5H5)ZrCl2, [(B(C6F5)3‐ NC‐nacnac)CpZrCl2], precatalyst (2) can be treated with low concentrations of methylaluminoxane (MAO) to generate active sites capable of copolymerizing ethylene with 1‐octadecene or norbornene under mild conditions. A series of poly(ethylene‐co‐octadecene) and poly(ethylene‐co‐norbornene) copolymers were prepared, and their properties were characterized by NMR, differential scanning calorimetry, and mechanical analysis. The results show that this system produced poly(ethylene‐co‐octadecene) copolymers with a branching content of about 8 mol %. However, upon increasing the comonomer concentration, a drastic reduction in the Mn of the product is observed concomitant with an increase in comonomer incorporation. This leads to a gradual decrease in Young's modulus and stress at break, indicating an increase in the “softness” of the copolymer. In the case of copolymerizations of ethylene and norbornene, the catalytic system (2/MAO) shows a substantial decrease in reactivity in the presence of norbornene and generates copolymer chains in which 5–10 mol % norbornene is in blocks. We also observe that ethylene norbornene copolymers exhibit a high degree of alternating insertions (close to 50%), as determined by NMR spectroscopy. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011
Combining cationic ring‐opening polymerization and click chemistry for the design of functionalized polyurethanes
Authors: Basko Malgorzata , Bednarek Melania , Billiet Leen , Kubisa Przemyslaw , Goethals Eric , Du Prez Filip 
Published: February 2011

AbstractA straightforward strategy for the synthesis and functionalization of polyurethanes (PUs) via the use of alkyne‐functionalized polytetrahydrofuran (PTHF) diols is described. The alkyne groups have been introduced into the PTHF chains by the cationic ring‐opening copolymerization of tetrahydrofuran and glycidyl propargyl ether. These PTHF prepolymers were combined with 1,4‐butanediol and hexamethylene diisocyanate for the synthesis of linear PUs with latent functionalization sites. The polyether segments of the PUs have then been coupled with several types of functionalized azides by the copper‐catalyzed azide‐alkyne “click” chemistry, for example with phosphonium containing azides for their antibacterial properties. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011
Synthesis and optoelectronic behavior of conjugated polymer poly(3‐hexylthiophene) grafted on multiwalled carbon nanotubes
Authors: Phuong Le Anh , Huang Tsai‐Ming , Chen Po‐Tsun , Yang Arnold Chang‐Mou 
Published: February 2011

AbstractA nanocomposite of multiwalled carbon nanotubes (CNTs) and poly(3‐hexylthiophene) (P3HT) was prepared by grafting P3HT uniformly on the surface of CNTs (P3HT/P3HT‐g‐CNT) via a “grafting from” method with the coating thicknesses controlled. It was found that as the coating thickness decreased, the crystallinity of the P3HT decreased, along with significant red‐shifting of Raman that signified alterations of chain conformation. Furthermore, although the photoluminescence (PL) peak remained unchanged when grafted on CNTs, modifications of P3HT energy gap was observed, indicating variations of vibronic levels arising from the grafting. Moreover, broadening of the PL emission took place that suggested decreasing of lifetimes of the photo‐generated species when grafted on CNTs. Bilayer photovoltaic devices with the (6,6)‐phenyl C61‐butyric acid methyl ester as the electron acceptor have shown that the nanocomposite P3HT/P3HT‐g‐CNT performed much more efficiently as the electron donor, in both photocurrent density and power conversion efficiency, compared with the neat P3HT. © 2011 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2011
Influence of strain rate and temperature on necking transition in a polydomain smectic main chain elastomer
Authors: Lentz Daniel M. , Chen Huipeng , Yu Ziniu , Patil Harshad P. , Crane Charles A. , Hedden Ronald C. 
Published: February 2011

AbstractSmectic main‐chain liquid crystalline elastomers (MCLCE) with polydomain morphology are rare examples of elastomers that can form a neck and undergo cold drawing under tension. However, not all previous studies of the mechanical behavior of smectic MCLCE reported neck formation. The mechanical response of a polydomain smectic MCLCE has therefore been characterized by elongation at varying strain rates and temperatures to identify factors favoring mechanical instability. Yielding and neck formation are increasingly favored as the strain rate increases at constant temperature, or as the temperature decreases toward Tg. As cold drawing proceeds, significant creep occurs continuously within the neck, in contrast to the behavior of certain linear polymers that exhibit a “natural” draw ratio. Thermal imaging during elongation indicates that viscous heating is not a prerequisite for neck formation. Rather, inherent softening of the material during yielding due to morphological changes leads to an enhanced rate of deformation and contraction at the neck. © 2011 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2011
Examining the links between perceived impact of breast cancer and psychosocial adjustment: the buffering role of posttraumatic growth
Authors: Silva Sónia Martins , Moreira Helena Cruz , Canavarro Maria Cristina 
Published: February 2011

AbstractObjectives: Finding positive changes in the aftermath of breast cancer (BC) may protect women against impaired adjustment. This study examines posttraumatic growth (PTG) in a sample of women receiving treatment for BC and explores the buffering role of PTG on the links between perceived impact of BC and emotional distress and quality of life (QoL).Methods: Seventy‐eight women receiving chemotherapy (n = 57) or radiotherapy (n = 21) completed the Portuguese versions of the Posttraumatic Growth Inventory, the Hospital Anxiety and Depression Scale, the World Health Organization for QoL‐Bref and Consequences sub‐scale of the Brief Illness Perception Questionnaire (assessing perceived impact of BC).Results: PTG was frequently reported and co‐existed with distress and dysfunction. A more negative perception of the impact of BC was significantly associated with higher emotional distress and impaired Physical and Psychological QoL, but was unrelated to PTG. Hierarchical regression analyses showed that PTG moderated these relationships, acting as a stress‐buffering mechanism. Among women who perceived BC as having a more negative impact on their lives, higher levels of PTG buffered this negative perceived impact on Psychological and Social QoL (p<0.01) and also on Depression (p<0.06). This effect was not found for Physical QoL and Anxiety.Conclusions: Results provide support for the stress‐buffering role of PTG. Finding positive changes in cancer experience seems to protect women from the effects of a negative perception of the impact of BC on adjustment. Psychosocial intervention programs should facilitate PTG in order to promote women's adjustment. Copyright © 2011 John Wiley & Sons, Ltd.
The factor structure of the revised Illness Perception Questionnaire in a population of oesophageal cancer survivors
Authors: Dempster Martin , McCorry Noleen K. 
Published: February 2011

AbstractObjectives: To determine whether the proposed seven‐factor structure of the Illness Perception Questionnaire—Revised (Timeline Acute/Chronic, Timeline Cyclical, Consequences, Personal Control, Treatment Control, Illness Coherence and Emotional Representations) is appropriate among a population of oesophageal cancer survivors.Methods: Everyone registered with the Oesophageal Patients' Association in the UK (n = 2185) was mailed a questionnaire booklet, which included the Illness Perception Questionnaire—Revised. Responses from 587 oesophageal cancer survivors (27%) were subjected to a confirmatory factor analysis.Results: The proposed seven‐factor structure provided a reasonable fit of the data. Modification indices suggested that a significantly better fit could be provided if one of the items on the Timeline Acute/Chronic factor loaded on the Treatment Control factor and an error covariance was added between two other items on the Timeline Acute/Chronic factor.Conclusions: The model fit for the seven‐factor structure proposed by Moss‐Morris et al. (Psychol Health 2002;17:1–16) was found to be adequate in our study. However, the structure of the timeline acute/chronic factor needs to be considered, particularly when the IPQ‐R is to be used among older people with a potentially life‐threatening illness or those receiving palliative care. Copyright © 2011 John Wiley & Sons, Ltd.
Distribution of the lymphatic vessels in the prostatic fascia
Authors: Soga Hideo , Takenaka Atsushi , Murakami Gen , Haraguchi Takahiro , Miyake Hideaki , Tanaka Kazushi , Fujisawa Masato 
Published: February 2011

AbstractBACKGROUNDThe prostatic fascia‐preserving procedure is effective for the early recovery of erectile function after radical prostatectomy; however, the long‐term influence of on cancer control was unknown. This study clarified the distribution of lymphatic vessels in the prostatic fascia.MATERIAL AND METHODSThe lymphatic vessels were analyzed in 10 prostates obtained from fixed Japanese cadavers (aged, 71–90 years old). Specimens were taken from the apex, the middle part, and the base of the right‐hand side of the prostate. Lymphatic vessels were detected by immunohistochemical stain using an antibody specific for the lymphatic endothelial cells (clone D2‐40). The lymphatic vessels were counted in the prostate capsule and the prostatic fascia of each section by light microscopy at low power (100×).RESULTSThe median number of lymphatic vessels in the prostatic capsule per prostatic half was 21.0, 14.0, and 21.0 in the apex, middle, and base part of the prostate, respectively. In the prostatic facia the median number of lymphatic vessels per prostatic half was 8.0, 3.0, and 13.0 in the apex, middle, and the base part of the prostate, respectively. In the apex and the middle part the lymphatic vessels in the prostatic fascia were fewer than those in the prostatic capsule. However, in the base part the number of lymphatic vessels in the prostatic fascia was similar to that in the prostatic capsule.CONCLUSIONSThe present study suggested the surgeon to pay more attention for the dissection of the fascia at the base of the prostate. Prostate 71:1294–1298, 2011. © 2011 Wiley‐Liss, Inc.
Androgen receptor regulates expression of the MUC1‐C oncoprotein in human prostate cancer cells
Authors: Rajabi Hasan , Joshi Maya Datt , Jin Caining , Ahmad Rehan , Kufe Donald 
Published: February 2011

AbstractBACKGROUNDThe MUC1 heterodimeric oncoprotein is aberrantly overexpressed in human prostate cancers with more aggressive pathologic and clinical features. However, the signals that regulate MUC1 expression in prostate cancer cells are not well understood.METHODSMUC1 expression was studied in androgen‐dependent and ‐independent prostate cancer cell lines by quantitative RT‐PCR, immunoblotting and assessment of MUC1 promoter activation. Chromatin immunoprecipitation (ChIP) studies were performed to assess androgen receptor (AR) occupancy on the MUC1 promoter. Post‐transcriptional regulation of MUC1 expression was assessed by miR‐125b‐mediated effects on activity of the MUC1 3′ untranslated region (3′UTR).RESULTSThe present studies demonstrate that AR occupies a consensus AR element on the MUC1 promoter in androgen‐dependent LNCaP, but not in androgen‐independent DU145 and PC3, prostate cancer cells. The results further show that AR downregulates MUC1 gene transcription. Stable introduction of exogenous AR in PC3 (PC3/AR) cells and then silencing of AR confirmed AR‐mediated repression of the MUC1 promoter. AR signaling has also been shown to drive miR‐125b expression. The present studies further demonstrate that miR‐125b suppresses MUC1 translation in LNCaP cells and that an anti‐sense miR‐125b upregulates expression of MUC1 protein. In addition, stable expression of miR‐125b in DU145 cells resulted in decreases in MUC1 levels.CONCLUSIONSThese findings demonstrate that AR signaling regulates MUC1 expression by transcriptional and posttranscriptional mechanisms in prostate cancer cells. Prostate 71:1299–1308, 2011. © 2011 Wiley‐Liss, Inc.
G‐protein alpha‐s and ‐12 subunits are involved in androgen‐stimulated PI3K activation and androgen receptor transactivation in prostate cancer cells
Authors: Liu Jianjun , Youn Hyewon , Yang Jun , Du Ningchao , Liu Jihong , Liu Hongwei , Li Benyi 
Published: February 2011

AbstractBACKGROUNDThe androgen receptor (AR) is a ligand‐dependent transcription factor that mediates androgenic hormone action in cells. We recently demonstrated the involvement of phosphoinositide 3‐OH kinase (PI3K) p110beta in AR transactivation and gene expression. In this study, we determined the upstream signals that lead to PI3K/p110beta activation and AR transactivation after androgen stimulation.METHODSHuman prostate cancer LAPC‐4 and 22Rv1 cell lines were used for the experiments. AR transactivation was assessed using an androgen responsive element‐driven luciferase (ARE‐LUC) assay. Cell proliferation was examined using BrdU incorporation and MTT assays. Target genes were silenced using small interfering RNA (siRNA) approach. Gene expression was evaluated at the mRNA level (real‐time RT‐PCR) and protein level (Western blot). PI3K kinase activities were measured using immunoprecipitation‐based in vitro kinase assay. The AR–DNA‐binding activity was determined using chromatin‐immunoprecipitation (ChIP) assay.RESULTSFirst, at the cellular plasma membrane, disrupting the integrity of caveolae microdomain with methyl‐β‐cyclodextrin (M‐β‐CD) abolished androgen‐induced AR transactivation and gene expression. Then, knocking down caveolae structural proteins caveolin‐1 or ‐2 with the gene‐specific siRNAs significantly reduced androgen‐induced AR transactivation. Next, silencing Gαs and Gα12 genes but not other G‐proteins blocked androgen‐induced AR transactivation and cell proliferation. Consistently, overexpression of Gαs or Gα12 active mutants enhanced androgen‐induced AR transactivation, of which Gαs active mutant sensitized the AR to castration‐level of androgen (R1881). Most interestingly, knocking down Gαs but not Gα12 subunit significantly suppressed androgen‐stimulated PI3K p110beta activation. However, ChIP analysis revealed that both Gαs or Gα12 subunits are involved in androgen‐induced AR interaction with the AR target gene PSA promoter region.CONCLUSIONThese data suggest that caveolae‐associated G‐protein alpha subunits are involved in AR transactivation by modulating the activities of different PI3K isoforms. Prostate 71:1276–1286, 2011. © 2011 Wiley‐Liss, Inc.
High‐dose‐rate brachytherapy boost to the dominant intra‐prostatic tumor region: Hemi‐irradiation of prostate cancer
Authors: Schick Ulrike , Popowski Youri , Nouet Philippe , Bieri Sabine , Rouzaud Michel , Khan Haleem , Weber Damien Charles , Miralbell Raymond 
Published: February 2011

AbstractBACKGROUNDTo assess the feasibility, toxicity, and outcome of prostate hemi‐irradiation with a high‐dose‐rate brachytherapy (HDR‐BT) boost for patients presumed to harbor dominant intra‐prostatic tumors in a single lobe.METHODSAfter 3D conformal external radiotherapy (3DCRT) to 64–64.4 Gy, 77 patients with non‐metastatic locally aggressive prostate cancer have been treated from 2000 to 2004, with HDR‐BT using temporary open MRI‐guided 192Ir implants, to escalate the dose in the boost region. Twenty patients (26%) had one lobe involvement (i.e., one sided endorectal MRI, rectal examination, and biopsies) and were boosted to one side of the gland only. A dose of 12, 14, and 16 Gy in two fractions was delivered to 5, 6, and 9 patients, respectively.RESULTSAfter a median follow‐up 69 months, no differences in late rectal toxicity were observed between the unilaterally and bilaterally irradiated cohorts. Although, grade 2 late urinary toxicity was worse in the hemi‐irradiated group (P = 0.03), severe grade ≥3 late urinary toxicity at 5 years was not different: 10% versus 8.8% in the unilaterally and bilaterally irradiated cohorts, respectively. Grade 4 late urinary toxicity, however, was exclusively observed in patients boosted to both lobes (5/57, 8.8%). Five‐year biochemical relapse‐free survival was 79.7% versus 70.5% for the unilateral and bilateral boost groups, respectively (P = 0.99).CONCLUSIONProstate hemi‐irradiation with a HDR‐BT boost to the dominant tumor region may be considered when rectal examination, MRI, and biopsies suggest one lobe involvement. Nevertheless, strict dosimetric optimization is needed in order to further reduce the risk of late severe toxicity. Prostate 71:1309–1316, 2011. © 2011 Wiley‐Liss, Inc.
Reduced levels of 5‐α reductase 2 in adult prostate tissue and implications for BPH therapy
Authors: Niu Yinong , Ge Rongbin , Hu Libing , Diaz Christian , Wang Zongwei , Wu Chin‐Lee , Olumi Aria F. 
Published: February 2011

AbstractBACKGROUND5‐α reductase 2 (5‐AR 2) is a key enzyme that is responsible of proper development of prostate tissue. Inhibition of 5‐AR 2 has proven to be efficacious for management of urinary symptoms secondary benign prostatic hyperplasia (BPH). However, some patients are resistant to the therapeutic effects of 5‐AR 2 inhibitor. We wished to determine why some benign non‐cancerous adult human prostates do not express 5‐AR 2, and hypothesized that methylation of 5‐AR 2 promoter region correlated with low expression of 5‐AR 2 protein.METHODSThe transition zone of 42 human prostate tissues after radical prostatectomy was used for evaluation. Initially, 21 paraffin embedded samples were used to assess immunoreactivity to 5‐AR 2 antibody in non‐cancerous BPH samples. In the next 21 samples, fresh frozen prostate transition zone samples without cancer were assessed for immunoreactivity and methylation of the 5‐AR 2 promoter using methyl‐specific PCR.RESULTSWe show that 6/21 (29%) of benign human prostate samples did not express the 5‐AR 2 protein. Moreover, the promoter region of 5‐AR 2 contains a CpG island that is methylated in benign prostate epithelial cells in culture and also in 39% (7/18) human prostate tissues. We show a strong correlation between methylation of the 5‐AR 2 promoter region and absence of 5‐AR 2 protein expression (P = 0.0025, Fisher's exact test).CONCLUSIONSMethylation of 5‐AR 2 promoter may account for low or absent expression of 5‐AR 2 in some human adult prostate tissues. Prostate 71:1317–1324, 2011. © 2011 Wiley‐Liss, Inc.
Construction of tissue micro array from prostate needle biopsies using the vertical clustering re‐arrangement technique
Authors: Fridman Eduard , Daya Dean , Srigley John , Whelan Kaitlyn F. , Lu Jian‐Ping , Pinthus Jehonathan H 
Published: February 2011

AbstractBACKGROUNDTissue microarray (TMA) allows for simultaneous rapid expression analysis of multiple molecular targets in many tissue specimens. TMA's are specifically in demand for the screening for diagnostic and prognostic markers in prostate cancer (PC). Consequently, TMAs from prostate needle biopsy (PNB) material taken at diagnosis before any treatment commenced are in demand. However, since PNB contain only limited amount of tumor arranged within a very thin tissue core, TMA construction from PNB is problematic.METHODSArchival PNB from 30 PC patients with variable Gleason scores (6–10) and % of cores involvement (30–90%) were used. Following selection of representative cores, the paraffin blocks were melted. Each core was sectioned into equal parts of 3–4 mm in length. For each case, a group of fragments was then re‐embedded in a vertical orientation. Using Manual TMA Apparatus, 2 mm cores from each of the vertically rearranged fragments were harvested. Sections (4 µm) were stained with H&E and with high‐molecular weight cytokeratin (HMWCK), PIN‐cocktail (p63 + p504S), and PSA immunohistochemical stains.RESULTSA TMA from PNB with a capacity of 80 serial 4 µm sections was constructed. In all cases, identical tumor and neighboring tissue morphology (atrophic changes and high‐grade prostatic intra‐epithelial neoplasia) with no loss of tissue was evident.CONCLUSIONSThe vertical clustering re‐arrangement (VCR) technique is suitable for large scale construction of TMA blocks from PNB maintaining the morphological and immunohistochemical characteristics of the original samples. This method is promising both in terms of archival tissue preservation and biomarkers research. Prostate 71:1374–1381, 2011. © 2011 Wiley‐Liss, Inc.
Design, synthesis and structure–activity relationship of novel coumarin derivatives
Authors: Guan Ai‐Ying , Liu Chang‐Ling , Li Miao , Zhang Hong , Li Zhi‐Nian , Li Zheng‐Ming 
Published: February 2011

AbstractBACKGROUND: The lead coumarin derivative (E)‐methyl 3‐methoxy‐2‐[2‐(4‐methylcoumarin‐7‐yloxymethyl)phenyl]acrylate was discovered by using an intermediate derivatisation method. To discover new coumarin derivatives with improved activity, a series of substituted coumarins were synthesised and bioassayed.RESULTS: The compounds were identified by 1H NMR, IR, MS and elemental analysis. Bioassays demonstrated that some of the title compounds exhibited excellent fungicidal activity against cucumber downy mildew at 25 mg L−1. The relationship between structure and fungicidal activity is reported.CONCLUSION: The present work demonstrates that coumarin derivatives containing methoxyacrylate moieties can be used as possible lead compounds for developing novel fungicides. Copyright © 2011 Society of Chemical Industry
Cloud statistics and cloud radiative effect for a low‐mountain site
Authors: Ebell Kerstin , Crewell Susanne , Löhnert Ulrich , Turner David D. , O'Connor Ewan J. 
Published: February 2011

AbstractIn 2007, the Atmospheric Radiation Measurement (ARM) Mobile Facility (AMF) was operated for a nine‐month period in the Murg Valley, Black Forest, Germany, in support of the Convective and Orographically‐induced Precipitation Study (COPS). The synergy of AMF and COPS partner instrumentation was exploited to derive a set of high‐quality thermodynamic and cloud property profiles with 30 s resolution. In total, clouds were present 72% of the time, with multi‐layer mixed phase (28.4%) and single‐layer water clouds (11.3%) occurring most frequently. A comparison with the Cloudnet sites Chilbolton and Lindenberg for the same time period revealed that the Murg Valley exhibits lower liquid water paths (LWPs; median = 37.5 g m−2) compared to the two sites located in flat terrain. In order to evaluate the derived thermodynamic and cloud property profiles, a radiative closure study was performed with independent surface radiation measurements. In clear sky, average differences between calculated and observed surface fluxes are less than 2% and 4% for the short wave and long wave part, respectively. In cloudy situations, differences between simulated and observed fluxes, particularly in the short wave part, are much larger, but most of these can be related to broken cloud situations. The daytime cloud radiative effect (CRE), i.e. the difference of cloudy and clear‐sky net fluxes, has been analysed for the whole nine‐month period. For overcast, single‐layer water clouds, sensitivity studies revealed that the CRE uncertainty is likewise determined by uncertainties in liquid water content and effective radius. For low LWP clouds, CRE uncertainty is dominated by LWP uncertainty; therefore refined retrievals, such as using infrared and/or higher microwave frequencies, are needed. Copyright © 2011 Royal Meteorological Society