bluuebunny/crossref_metadata_2025 huggingface dataset:
A Versatile Synthesis of Cyclic Diphenyl Ether‐Type Diarylheptanoids: Acerogenins, (±)‐Galeon, and (±)‐Pterocarine
Authors: Jeong Byeong‐Seon , Wang Qian , Son Jong‐Keun , Jahng Yurngdong
Published: January 2007

A versatile method for the total synthesis of cyclic diphenyl ether‐type diarylheptanoids, acerogenin C, acerogenin L, (±)‐galeon, and (±)‐pterocarine was described. The Ullmann reaction of suitably substituted linear diphenylheptanoids was employed for the intramolecular formation of the key ether intermediates as the final step. The prerequisite diarylheptanoids were prepared by a series of cross‐aldol condensation reactions from readily available starting benzaldehydes.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
Separation of enantiomers of deprenyl with various CDs in CE and the effect of enantiomer migration order on enantiomeric impurity determination of selegiline in active ingredients and tablets
Authors: Castro‐Puyana María , Lomsadze Ketevan , Crego Antonio L. , Marina María Luisa , Chankvetadze Bezhan
Published: January 2007

Opposite affinity pattern of enantiomers of the antiparkinsonian chiral drug deprenyl (DEP) was observed towards various neutral and charged derivatives of β‐CD. The effect of the enantiomer migration order on the LOD of enantiomeric impurity of R‐DEP (selegiline) was studied for the standard substances and in the tablets from three different suppliers. The influence of injection mode on the LOD of a minor enantiomeric impurity was also studied and the CE method was compared with the pharmacopoeial HPLC method using a commercially available chiral column Chiralcel OD‐H. The optimized CE method was more suitable for low‐level enantiomeric impurity determination in selegiline compared to the pharmacopoeial HPLC method.
c‐MYC activation impairs the NF‐κB and the interferon response: Implications for the pathogenesis of Burkitt's lymphoma
Authors: Schlee Martin , Hölzel Michael , Bernard Sandra , Mailhammer Reinhard , Schuhmacher Marino , Reschke Judith , Eick Dirk , Marinkovic Dragan , Wirth Thomas , Rosenwald Andreas , Staudt Louis M. , Eilers Martin , Baran‐Marszak Fanny , Fagard Remi , Feuillard Jean , Laux Gerhard , Bornkamm Georg W.
Published: January 2007

Deregulation of the proto‐oncogene c‐myc is a key event in the pathogenesis of many tumors. A paradigm is the activation of the c‐myc gene by chromosomal translocations in Burkitt lymphoma (BL). Despite expression of a restricted set of Epstein–Barr viral (EBV) antigens, BL cells are not recognized by antigen‐specific cytotoxic T cells (CTLs) because of their inability to process and present HLA class I‐restricted antigens. In contrast, cells of EBV‐driven posttransplant lymphoproliferative disease (PTLD) are recognized and rejected by EBV‐specific CTLs. It is not known whether the poor immunogenicity of BL cells is due to nonexpression of viral antigens, overexpression of c‐myc, or both. To understand the basis for immune recognition and escape, we have compared the mRNA expression profiles of BL and EBV‐immortalized cells (as PTLD model). Among the genes expressed at low level in BL cells, we have identified many genes involved in the NF‐κB and interferon response that play a pivotal role in antigen presentation and immune recognition. Using a cell line in which EBNA2 and c‐myc can be regulated at will, we show that c‐MYC negatively regulates STAT1, the central player linking the Type‐I and Type‐II interferon response. Switching off c‐myc expression leads to STAT1 induction through a direct and indirect mechanism involving induction of Type‐I interferons. c‐MYC thus masks an interferon‐inducing activity in these cells. Our findings imply that immune escape of tumor cells is not only a matter of in vivo selection but may be additionally promoted by activation of a cellular oncogene. © 2007 Wiley‐Liss, Inc.
Reproductive factors and family history of breast cancer in relation to plasma prolactin levels in premenopausal and postmenopausal women
Authors: Eliassen A. Heather , Tworoger Shelley S. , Hankinson Susan E.
Published: January 2007

Many reproductive factors are associated with breast cancer risk, potentially through a hormonal pathway. The peptide hormone prolactin is essential in mammary development and lactation and may be a link between risk factors and breast cancer. While higher prolactin levels are associated with increased breast cancer risk, few determinants of prolactin levels are known. We conducted a cross‐sectional analysis among 1,089 premenopausal and 1,311 postmenopausal women within the Nurses' Health Study (NHS) and the NHS II to examine the associations of reproductive factors, benign breast disease and family history of breast cancer with plasma prolactin levels. Parous women had significantly lower prolactin levels than nulliparous women (parous vs. nulliparous multivariate‐adjusted geometric means = 14.1 ng/mL vs. 16.6 ng/mL, p < 0.001 for premenopausal and 9.1 vs. 10.1, p = 0.04 for postmenopausal women), although levels did not decrease with increasing number of children for either premenopausal (p‐trend = 0.23) or postmenopausal (p‐trend = 0.07) parous women. Age at first birth was not associated with prolactin levels. The reduction in prolactin levels among parous premenopausal women appeared to attenuate with increasing time since first birth, but the trend was not statistically significant (p‐trend = 0.12). Age at menarche, duration of lactation and benign breast disease were not associated with prolactin levels. Family history of breast cancer was associated with significantly higher prolactin levels when compared with no family history among premenopausal (15.9 ng/mL vs. 14.3 ng/mL, p = 0.04) but not postmenopausal (p = 0.73) women. In conclusion, the associations of parity and family history with breast cancer risk may be mediated, at least in part, by prolactin levels. © 2006 Wiley‐Liss, Inc.
A prospective cohort study of red wine consumption and risk of prostate cancer
Authors: Sutcliffe Siobhan , Giovannucci Edward , Leitzmann Michael F. , Rimm Eric B. , Stampfer Meir J. , Willett Walter C. , Platz Elizabeth A.
Published: January 2007

In light of recent, strong inverse findings between lifetime red wine consumption and prostate cancer among younger men, we revisited our previous cohort analysis to more thoroughly investigate red wine consumption and prostate cancer in the Health Professionals Follow‐up Study (HPFS). In 1986, HPFS participants reported their average consumption of red wine, white wine, beer and liquor during the past year, and their change in alcohol consumption over the prior 10 years. Prostate cancer diagnoses were ascertained on each biennial questionnaire and confirmed by medical record review. Between 1986 and 2002, 3,348 cases of prostate cancer were diagnosed among 45,433 eligible participants. Using men who did not consume red wine as the reference, no linear trend was observed between red wine consumption and prostate cancer in the full analytic cohort (p‐trend = 0.57). Among men with unchanged alcohol consumption in the prior 10 years, and those additionally <65 years of age, slightly lower risks were observed for men who consumed ≤4 glasses of red wine/week, whereas null or slight increased risks were observed for men who consumed ≫4 glasses/week, resulting in a lack of linear trend. These findings suggest that red wine does not contribute appreciably to the etiology of prostate cancer. © 2006 Wiley‐Liss, Inc.
Breast conservation: Current results and future perspectives at the European Institute of Oncology
Authors: Veronesi Umberto , Zurrida Stefano
Published: January 2007

In the recent 10 years breast cancer treatments' scenario is radically changed. Extraordinary new surgical approaches give more and more conservative solutions both for the breast and especially for the axilla avoiding dissection in more than 80% of early cases. Instrumental early diagnosis and clinical prediction are now able to identify very initial cases often in premalignant stage. Technology arrived in the operating theatre for the intraoperative radiotherapy treatments giving to the patients the better quality of life with the help also of the plastic surgeons. There are still near horizons to reach: modern neo‐adjuvant and adjuvant treatments are going quickly from the laboratory to patient's bed. © 2007 Wiley‐Liss, Inc.
Pravastatin induces thrombomodulin expression in TNFα‐treated human aortic endothelial cells by inhibiting Rac1 and Cdc42 translocation and activity
Authors: Lin Shing‐Jong , Chen Yung‐Hsiang , Lin Feng‐Yen , Hsieh Li‐Yuan , Wang Shu‐Huei , Lin Chia‐Ying , Wang Yu‐Chieh , Ku Hung‐Hai , Chen Jaw‐Wen , Chen Yuh‐Lien
Published: January 2007

Expression of functionally active thrombomodulin (TM) on the luminal surface of endothelial cells is critical for vascular thromboresistance. The 3‐hydroxyl‐3‐methyl coenzyme A reductase inhibitor, pravastatin, can protect the vasculature in a manner that is independent of its lipid‐lowering activity. We examined the effect of pravastatin on TM expression by human aortic endothelial cells (HAECs) with subsequent tumor necrosis factor α (TNFα) stimulation and investigated the signaling pathways involved. TNFα treatment attenuated TM expression in HAECs in a time‐dependent manner. Pravastatin upregulated TM levels in TNFα‐treated HAECs. Specific inhibition of geranylgeranyltransferase‐I or the Rho family by GGTI‐286 or TcdB, respectively, enhanced TM expression in TNFα‐treated HAECs, whereas MAP kinase inhibitors, inactivation of Rho by Clostridium botulinum C3 exoenzyme, or the Rho kinase inhibitor, Y‐27632, had no effect. In TNFα‐treated HAECs, pravastatin inhibited Rac1 and Cdc42 activation and their translocation to the cell membrane. Blocking the transcriptional activation of NF‐κB prevented the TNFα‐induced downregulation of TM. The pravastatin‐induced increase in TM expression in TNFα‐treated HAECs was mediated through inhibition of NF‐κB activation. Pravastatin regulates TM expression by inhibiting the activation of the Rho family proteins, Rac1 and Cdc42, and the transcription factor, NF‐κB. The increase in endothelial TM activity in response to pravastatin constitutes a novel pleiotropic (nonlipid‐related) effect of this commonly used compound and may be of clinical significance in disorders in which deficient endothelial TM plays a pathophysiological role. J. Cell. Biochem. 101: 642–653, 2007. © 2007 Wiley‐Liss, Inc.
Interleukin‐1β upregulates Na+‐K+‐2Cl− cotransporter in human middle ear epithelia*
Authors: Kim Su Jin , Choi Jae Young , Son Eun Jin , Namkung Wan , Lee Min Goo , Yoon Joo‐Heon
Published: January 2007

Disruption of periciliary fluid homeostasis is the main pathogenesis of otitis media with effusion (OME), one of the most common childhood diseases. Although the underlying molecular mechanisms are unclear, it has been suggested that the altered functions of ion channels and transporters are involved in the fluid collection of middle ear cavity of OME patients. In the present study, we analyzed the effects of a major cytokine interleukin (IL)‐1β, which was known to be involved in the pathogenesis of OME, on Na+‐K+‐2Cl− cotransporter (NKCC) in human middle ear cells. Intracellular pH (pHi) was measured in primary cultures of normal human middle ear epithelial (NHMEE) cells using a double perfusion chamber, which enabled us to analyze the membrane‐specific transporter activities. NKCC activities were estimated by the pHi reduction due to bumetanide‐sensitive intracellular uptake of NH. In NHMEE cells, NKCC activities were observed only in the basolateral membrane, and immunoblotting using specific antibodies revealed the expression of NKCC1. Interestingly, IL‐1β treatments augmented the basolateral NKCC activities and increased NKCC1 expression. In addition, IL‐1β treatments stimulated bumetanide‐sensitive fluid transport across the NHMEE cell monolayers. Furthermore, an elevated NKCC1 expression was observed in middle ear cells from OME patients when compared to those from control individuals. The above results provide in vitro and in vivo evidence that the inflammatory cytokine IL‐1β upregulates NKCC1 in middle ear epithelial cells, which would be one of the important underlying mechanisms of excess fluid collection in OME patients. J. Cell. Biochem. 101: 576–586, 2007. © 2007 Wiley‐Liss, Inc.
Increased expression of integrin β1 subunit enhances p21WAF1/Cip1 transcription through the Sp1 sites and p300‐mediated histone acetylation in human hepatocellular carcinoma cells
Authors: Fang Zhengyu , Fu Yi , Liang Yulong , Li Zengxia , Zhang Wen , Jin Jiawei , Yang Yong , Zha Xiliang
Published: January 2007

Integrins, a class of membrane receptors, are major players in transmitting the mechanical force across the plasma membrane. We previously reported that overexpression of integrin β1 subunit imposed a growth inhibitory effect on the hepatocellular carcinoma cell line SMMC‐7721 through transcriptional activation of p21WAF1/CIP1 gene. In this study, we further determined the molecular mechanisms underlying p21WAF1/CIP1 expression induced by integrin β1 overexpression. We report herein that overexpression of integrin β1 subunit upregulates p21WAF1/Cip1 transcription through a p53‐independent pathway. The overexpressed integrin β1 activates the p21WAF1/Cip1 promoter through the Sp1/Sp3 sites and makes more transcription factor Sp1 recruited to the proximal p21 promoter region. In addition, it makes the acetylation value of histone proteins increased across some parts of the p21WAF1/Cip1 gene, especially in the promoter region. The transcriptional co‐activator p300, which possesses intrinsic histone acetyltransferase, was found to be involved in the integrin β1‐mediated histone acetylation and p21 transcriptional activation. Therefore, these findings presented the mechanisms by which integrin β1 induced the elevated p21 expression in hepatic cancer cells. J. Cell. Biochem. 101: 654–664, 2007. © 2007 Wiley‐Liss, Inc.
An enumeration of graphical designs
Authors: Chee Yeow Meng , Kaski Petteri
Published: January 2007

Let Ψ(t,k) denote the set of pairs (v,λ) for which there exists a graphical t‐(v,k,λ) design. Most results on graphical designs have gone to show the finiteness of Ψ(t,k) when t and k satisfy certain conditions. The exact determination of Ψ(t,k) for specified t and k is a hard problem and only Ψ(2,3), Ψ(2,4), Ψ(3,4), Ψ(4,5), and Ψ(5,6) have been determined. In this article, we determine completely the sets Ψ(2,5) and Ψ(3,5). As a result, we find more than 270,000 inequivalent graphical designs, and more than 8,000 new parameter sets for which there exists a graphical design. Prior to this, graphical designs are known for only 574 parameter sets. © 2006 Wiley Periodicals, Inc. J Combin Designs 16: 70–85, 2008
Utility of the psychological screening inventory: A review
Authors: Lanyon Richard I.
Published: January 2007

The Psychological Screening Inventory (PSI; R. I. Lanyon, 1970, 1973, 1978, 1993, 2006) was developed as a cost‐effective screening device in identifying persons for whom a more complete psychological evaluation should be conducted. The author reviews data bearing on the utility of the PSI in this regard and in more general applications. The Alienation scale showed strong effect sizes in distinguishing psychiatric inpatients from controls, the Social Nonconformity scale in distinguishing incarcerated groups from control, and the Discomfort scale in identifying persons with general psychological distress. These findings were supported by correlational data with comparable scales, and by a variety of smaller comparison studies. Meaningful discriminations were also shown for adolescents and for college‐age young adults. Findings in studies of substance abusers and medical problems were also reviewed. Response Distortion scales showed effectiveness similar to that of the Minnesota Multiphasic Personality Inventory‐2 (MMPI‐2; J. N. Butcher, W. G. Dahlstrom, J. R. Graham, A. Tellegen, & B. Kaemmer, 1989) validity scales. Validity was also shown for several of the seven available foreign language translations. It was concluded that the PSI is effective for the tasks for which it was designed. © 2007 Wiley Periodicals, Inc. J Clin Psychol 63: 283–307, 2007.
Does psychotherapy research inform treatment decisions in private practice?
Authors: Stewart Rebecca E. , Chambless Dianne L.
Published: January 2007

Psychologists in independent practice (N = 591) were surveyed regarding their approach to treatment decisions, specifically the use of research on empirically supported treatments (ESTs) to inform practice. All participants received a case study of a patient with panic disorder, and half were randomly assigned to receive a research summary on evidence‐based treatments for panic disorder (cognitive–behavioral therapy and pharmacotherapy). Practitioners reported that they rely primarily on clinical experiences to inform treatment decisions, although they often consult EST literature. Those who received the research summary were significantly more likely to report they would use an EST. These results indicate that providing information about ESTs can impact practice. Although this sample was more positive about EST research than clinicians are often depicted to be, this study indicates an enduring research–practice gap in clinical psychology. © 2007 Wiley Periodicals, Inc. J Clin Psychol 63: 267–281, 2007.
Overlap in consistent cycles
Authors: Miklavič Štefko , Potočnik Primož , Wilson Steve
Published: January 2007

A (directed) cycle C in a graph Γ is called consistent provided there exists an automorphism of Γ, acting as a 1‐step rotation of C. A beautiful but not well‐known result of J.H. Conway states that if Γ is arc‐transitive and has valence d, then there are precisely d − 1 orbits of consistent cycles under the action of Aut(Γ). In this paper, we extend the definition of consistent cycles to those which admit a k‐step rotation, and call them ${1}\over{k}$‐consistent. We investigate ${1}\over{k}$‐consistent cycles in view of their overlap. This provides a simple proof of the original Conway's theorem, as well as a generalization to orbits of ${1}\over{k}$‐consistent cycles. A set of illuminating examples are provided. © 2007 Wiley Periodicals, Inc. J Graph Theory 55: 55–71, 2007
Solution of fink & straight conjecture on path‐perfect complete bipartite graphs
Authors: Cao Weiting , Hamburger Peter
Published: January 2007

We consider various edge disjoint partitions of complete bipartite graphs. One case is where we decompose the edge set into edge disjoint paths of increasing lengths. A graph G is path‐perfect if there is a positive integer n such that the edge set E(G) of the graph G can be partitioned into paths of length 1,2,3,…,n. The main result of the paper is the proof of the conjecture of Fink and Straight [4]: A complete bipartite graph Ks,t on t + s vertices (t ≤ s) is path‐perfect if and only if there is a positive integer n such that the following two conditions are satisfied;

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Our proof gives a linear time algorithm to find an edge disjoint partition of a complete bipartite graph into paths of lengths 1,2,3,…,n. © 2007 Wiley Periodicals, Inc. J Graph Theory 55:91–111, 2007
Edge proximity conditions for extendability in cubic bipartite graphs
Authors: Aldred R. E. L. , Jackson Bill
Published: January 2007

We show that a set M of m edges in a cyclically (3m − 2)‐edge‐connected cubic bipartite graph is contained in a 1‐factor whenever the edges in M are pairwise distance at least f(m) apart, where

© 2007 Wiley Periodicals, Inc. J Graph Theory 55: 112–120, 2007
A lower bound on the order of regular graphs with given girth pair
Authors: Balbuena C. , Jiang T. , Lin Y. , Marcote X. , Miller M.
Published: January 2007

The girth pair of a graph gives the length of a shortest odd and a shortest even cycle. The existence of regular graphs with given degree and girth pair was proved by Harary and Kovács [Regular graphs with given girth pair, J Graph Theory 7 (1983), 209–218]. A (δ, g)‐cage is a smallest δ‐regular graph with girth g. For all δ ≥ 3 and odd girth g ≥ 5, Harary and Kovács conjectured the existence of a (δ,g)‐cage that contains a cycle of length g + 1. In the main theorem of this article we present a lower bound on the order of a δ‐regular graph with odd girth g ≥ 5 and even girth h ≥ g + 3. We use this bound to show that every (δ,g)‐cage with δ ≥ 3 and g ∈ {5,7} contains a cycle of length g + 1, a result that can be seen as an extension of the aforementioned conjecture by Harary and Kovács for these values of δ, g. Moreover, for every odd g ≥ 5, we prove that the even girth of all (δ,g)‐cages with δ large enough is at most (3g − 3)/2. © 2007 Wiley Periodicals, Inc. J Graph Theory 55: 153–163, 2007
Prediction of fibre components in oat hulls by near infrared reflectance spectroscopy
Authors: Redaelli Rita , Berardo Nicola
Published: January 2007

The fibre fractions of oat (Avena sativa L.) hulls, i.e. neutral detergent fibre (NDF), acid detergent fibre (ADF) and acid detergent lignin (ADL), were evaluated, using a specifically developed near infrared reflectance spectroscopy (NIRS) equation model, in a set of cultivars grown in various locations across Italy. The results indicated that the NIRS technique can accurately predict the fibre composition of oat hulls. Statistical analysis of variance underlined the strong impact of cultivar on the accumulation of fibre components, whereas location generally played a minor role. The largest variability among cultivars was observed in ADL content, whereas the range of variation in NDF and ADF contents appeared to be reduced. The description of the chemical characteristics of oat hulls could be helpful in determining the most suitable end‐use for specific cultivars. Copyright © 2007 Society of Chemical Industry
Bioactivity of extracts from gonadal tissue of the edible Australian purple sea urchin Heliocidaris erythrogramma
Authors: Sheean Paul D , Hodges Lynn D , Kalafatis Nicolette , Wright Paul FA , Wynne Paul M , Whitehouse Michael W , Macrides Theodore A
Published: January 2007

Dichloromethane (DCM), methanol (MeOH) and aqueous extracts of male gonadal tissue from Heliocidaris erythrogramma were screened for bioactivity. None of the extracts were antibacterial against Gram‐positive Staphylococcus aureus and Gram‐negative Escherichia coli. The aqueous extract scavenged the reactive oxygen species (ROS), hydrogen peroxide (H2O2), but did not react with the hydroxyl radical (OH·) or with the stable free radical 2,2‐diphenyl‐1‐picrylhydrazyl (DPPH·). No antioxidant potential was evident for the DCM and MeOH extracts. The extracts displayed various levels of anti‐inflammatory action in connection with inhibition of cyclooxygenase (ovine COX‐1 and COX‐2), but were insignificant inhibitors of lipoxygenase (soybean 15‐LO) pure enzyme. Anti‐inflammatory action related to reduction of leukotriene production by stimulated porcine neutrophils was affected only by the aqueous extract. The DCM and aqueous extracts, but not the MeOH extract, showed anti‐inflammatory activity in rats developing adjuvant‐induced polyarthritis. Overall, the DCM extract was 75% inhibitory of arthritis symptoms, and the aqueous extract was 55% inhibitory. Suppression of growth of the mouse leukaemic lymphoblastic (P388) cell line was evident for the DCM extract only. This extract was also able to exert a cytotoxic effect on the tumour cell line. For all extracts, no general cytotoxicity against isolated rat hepatocytes was observed. Copyright © 2007 Society of Chemical Industry
Fatty acid composition of herring (Clupea harengus L.): influence of time and place of catch on n‐3 PUFA content
Authors: Jensen Kristina Nedenskov , Jacobsen Charlotte , Nielsen Henrik Hauch
Published: January 2007

The fatty acid composition (FAC) was determined in muscle samples from 963 herring (Clupea harengus L.) caught during 2001–2003 in waters around Denmark. The overall variation in FAC was mainly related to seasonal (summer or winter) and annual (2001, 2002 or 2003) variation. No clear variation due to place of catch (Baltic Sea, Skagerrak, Kattegat or the northern, western or eastern part of the North Sea) was found. Of the nutritionally important n‐3 fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), EPA seemed to show a seasonal variation, with the highest amount during summer, whereas no periodic variation was observed for DHA. Herring from one catch, however, were found to have an extraordinarily high amount of EPA (11%) compared with all other catches (amounts of EPA ranging from 4 to 8%). This high EPA content found only in herring caught in May 2003 in the northern North Sea (NSN) was in large contrast to the herring caught in the same place 3 months earlier, which had the lowest EPA content overall. The abrupt increase in EPA level from February to May was not correlated with biological parameters such as spawning type, maturity status, age, sex and size, but it might be related to variation in the FAC of the calanoid copepods on which the herring feed. Considering the nutritional aspects, the high‐EPA herring from the NSN catch in May 2003 had a relatively low lipid content (7%), making them highly suitable for human consumption. Copyright © 2007 Society of Chemical Industry
Insight into the host–parasite interplay by proteomic study of host proteins copurified with the human parasite, Schistosoma japonicum
Authors: Liu Feng , Hu Wei , Cui Shu‐Jian , Chi Ming , Fang Cai‐Yun , Wang Zhi‐Qin , Yang Peng‐Yuan , Han Ze‐Guang
Published: January 2007

The tegument proteins of schistosome have attracted the most attention in studies of host–parasite interplay, while the host proteins acting at the host–parasite interface remained largely elusive. Here, we undertook a high‐throughput proteomic approach to characterize the schistosome‐adsorbed host proteins. Fifty five distinct host proteins were confidently identified in S. japonicum samples, including cercaria, schistosomula, adults, eggs, and miracidia, together with tegument and eggshell preparations, of which 23 and 38 host proteins were identified in adult worms and eggs, respectively. Among the schistosome‐adsorbed host proteins, host neutrophil elastases were found in the granuloma initiated by schistosome egg deposition, implying that the host innate immune molecules could participate in the granuloma formation for fighting against schistosome invasion, except for the adaptive immune system. In addition, some host proteins, such as proteinase inhibitor and superoxide dismutase, might be utilized by schistosome to counteract or attenuate the host attacks. These parasite‐adsorbed host proteins will provide new insights into the host immune responses against schistosome infection, the evasive behavior of the adult worms, and the granuloma formation, which could render an in‐depth understanding for the host–parasite interplay.
Influence of Ki‐ras‐driven oncogenic transformation on the protein network of murine fibroblasts
Authors: Recktenwald Christian V. , Mendler Simone , Lichtenfels Rudolf , Kellner Roland , Seliger Barbara
Published: January 2007

Ki‐ras gene mutations that specifically occur in codons 12, 13 and 61 are involved in the carcinogenesis of acute myeloid leukemia, melanoma and different carcinomas. In order to define potential mutation‐specific therapeutic targets, stable transfectants of NIH3T3 cells carrying different Ki‐ras4B gene mutations were generated. Wild type Ki‐ras transformants, mock transfectants and parental cells served as controls. These in vitro model systems were systematically analyzed for their protein expression pattern using two‐dimensional gel electrophoresis followed by mass spectrometry and/or protein sequencing. Using this approach, a number of target molecules that are differentially but coordinately expressed in the ras transfectants were identified next to other proteins that exhibit a distinct regulation pattern in the different cell lines analyzed. The differentially expressed proteins predominantly belong to the families of cytoskeletal proteins, heat shock proteins, annexins, metabolic enzymes and oxidoreductases. Their validation was assessed by real‐time quantitative RT‐PCR and/or Western blot analysis. Our results suggest that the Ki‐ras‐transformed cells represent a powerful tool to study Ki‐ras gene mutation‐driven protein expression profiles. In addition, this approach allows the discovery of ras‐associated cellular mechanisms, which might lead to the identification of physiological targets for pharmacological interventions of the treatment of Ki‐ras‐associated human tumors.
Predicting peptides bound to I‐Ag7 class II histocompatibility molecules using a novel expectation‐maximization alignment algorithm
Authors: Chang Kuan Y. , Suri Anish , Unanue Emil R.
Published: January 2007

The useful structural features of class II MHC molecules are rarely integrated into T‐cell epitope predictions. We propose an approach that applies a novel expectation‐maximization algorithm to align the naturally processed peptides selected by the class II MHC I‐Ag7 molecule – focusing on the five MHC‐specific anchor positions. Based on the alignment profile, log of odds (LOD) scores supplemented with the Laplace plus‐one pseudocounts method are applied to identify the potential T‐cell epitopes. In addition, an innovative computational concept of hindering residues using statistical and structural information is developed to refine the prediction. Performance analysis by receiver operating characteristics statistics and the experimental validation of the LOD scores demonstrate the accuracy of our predictive model. Furthermore, our model successfully predicts T‐cell epitopes of hen egg‐white lysozyme protein antigen. Our study provides a framework for predicting T‐cell epitopes in class II MHC molecules.
Facile synthesis of conjugated rod‐coil block copolymers
Authors: Wang Hengbin , Jost Robert , Wudl Fred
Published: January 2007

A facile synthetic approach of conjugated rod‐coil block copolymers with poly(para‐phenylene) as the rod block and polystyrene or polyethylene glycol as the coil block was developed. The block copolymers were synthesized through a TEMPO‐mediated radical polymerization of 3,5‐cyclohexadiene‐1,2‐diol‐derived monomers (diacetate, dibenzonate, and dicarbonate), followed by thermal aromatization of the polymer precursor. The living character of the polymerization and the structure of the copolymers were studied by NMR, GPC, TGA, and UV–vis spectroscopy. The average conjugation lengths of the copolymers were calculated according to their maxima in UV–vis spectroscopy. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 800–808, 2007
Photosensitive polybenzoxazole based on a poly(o‐hydroxy amide), a dissolution inhibitor, and a photoacid generator
Authors: Ogura Tomohito , Ueda Mitsuru
Published: January 2007

A positive‐type photosensitive polybenzoxazole (PSPBO), based on a poly(o‐hydroxy amide) (PHA), the dissolution inhibitor (DI) 9,9‐bis(4‐tert‐butoxycarbonyloxyphenyl)fluorene (t‐Boc BHF), and the photoacid generator (5‐propylsulfonyloxyimino‐5H‐thiophene‐2‐ylidene)‐(2‐methylphenyl)acetonitrile (PTMA), was developed. Several new tert‐butoxycarbonylated compounds as DIs for PSPBOs were prepared from phenolic compounds having a cardolike structure with di‐tert‐butyl dicarbonate in the presence of 4‐dimethylaminopyridine. Among them, t‐Boc BHF and 5,5′,6,6′‐tetra(tert‐butoxycarbonyl)‐3,3,3′,3′‐tetramethyl‐1,1′‐spirobiindane acted as excellent DIs, giving a large dissolution contrast between the exposed and unexposed areas in a 2.38 wt % tetramethylammonium hydroxide solution (TMAHaq)/5 wt % iso‐propanol (i‐PrOH). The dissolution behavior of this PSPBO system was studied in relation to the PTMA and t‐Boc BHF loadings and postexposure baking temperature. A PSPBO consisting of PHA (77 wt %), t‐Boc BHF (20 wt %), and PTMA (3 wt %) exhibited a sensitivity of 34 mJ/cm2 and a contrast of 5.8 when exposed to 365‐nm light (i‐line) and developed with an aqueous alkaline developer, 2.38 wt % TMAHaq/5 wt % i‐PrOH. A clear, positive image with 6‐μm features and a 10‐μm‐thick pattern with high sensitivity and contrast was produced by contact printing and converted into polybenzoxazole patterns upon heating at 350 °C for 1 h. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 661–668, 2007
Preparation and characterization of heteroarm H‐shaped terpolymers by combination of reversible addition‐fragmentation transfer polymerization and ring‐opening polymerization
Authors: Han De‐Hui , Pan Cai‐Yuan
Published: January 2007

Heteroarm H‐shaped terpolymers, [(poly(L‐lactide))(polystyrene)]poly(ethylene oxide)[(polystyrene)(poly(L‐lactide))], [(PLLA)(PS)]PEO[(PS)(PLLA)], in which PEO acts as a main chain and PS and PLLA as side arms, have been successfully prepared via combination of reversible addition–fragmentation transfer (RAFT) polymerization and ring‐opening polymerization (ROP). The first step is the synthesis of the PEO capped with one terminal dithiobenzoate group and one hydroxyl group at every chain end, [(HOCH2)(PhC(S)S)]PEO[(S(S)CPh)(CH2OH)] from the reaction of carboxylic acid with ethylene oxide. Then, the RAFT polymerization of styrene (St) was carried out using [(HOCH2)(PhC(S)S)]PEO[(S(S)CPh)(CH2OH)] as RAFT agent and AIBN as initiator, and the triblock copolymer, [(HOCH2)(PS)]PEO[(PS)(CH2OH)], was formed. Finally, the heteroarm H‐shaped terpolymers, [(PLLA)(PS)]PEO[(PS)(PLLA)], were produced by ROP of LLA, using triblock copolymer, [(HOCH2)(PS)]PEO[(PS)(CH2OH)], as macroinitiator and Sn(Oct)2 as catalyst. The target products and intermediates were characterized by 1H NMR spectroscopy and gel permeation chromatography. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 789–799, 2007
Sequence distribution and crystal structure of poly(ethylene/butylene terephthalate) copolyesters compared with poly(ethylene/trimethylene terephthalate) copolyesters
Authors: Shyr Tien‐Wei , Lo Chih‐Ming , Ye Sheng‐Rong , Bian Jie
Published: January 2007

Poly(ethylene/butylene terephthalate) (EB) copolyesters were synthesized from ethylene glycol (EG), 1,4‐butanediol (BDO), and dimethyl terephthalate with different molar volume ratios. The constitutional units, characterized by 13C NMR, revealed a random distribution in the molecular chain. Nevertheless, crystallites formed across the full range of EG/BDO composition can be observed with the use of a differential scanning calorimeter and a wide angle X‐ray diffraction method. The reflection profile of the EB copolyesters was deconvoluted. Also, in the poly(ethylene/trimethylene terephthalate) (ET) copolyesters previously studied, the crystal structure was dominated by the sequence distribution of the copolyesters. The crystal structures of EB and ET copolyesters, in comparison with the different constitutional repeating units in the molecular chain, are discussed in this study. The glass transition temperature of EB and ET copolyesters were analyzed, considering the copolymer composition and the sequencing of the monomers, and their values were compared to the Johnston's equation. In addition, the analysis of the melting temperatures of both the EB and the ET copolyesters was carried out. The equilibrium melting temperatures of both copolyesters were calculated according to the Hoffman‐Weeks extrapolative method. © 2007 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 45: 405–419, 2007
Mechanical degradation of polypropylene solutions under large pressure drops
Authors: Martini Raquel E. , Brignole Esteban A. , Barbosa Silvia E.
Published: January 2007

The degradation of polypropylene (PP), dissolved in n‐alkanes at high temperatures and pressures, during the solution discharge to ambient conditions was experimentally studied. Molecular weight distributions (MWD) of the solubilized PP were measured by gel permeation chromatography. The MWD curves of PP obtained after discharge of the polymer solution shift to the low molecular weight side of the distribution and the polydispersity is reduced. In this work, a systematic study on the discharge products was performed to elucidate the degradation mechanism and the effects of temperature and concentration on this phenomenon. Initially, pure polymers, PP and polystyrene (PS) were studied varying the solution temperature. In a second stage, the effect of polymer concentration on chain scission was assessed using experiments on physical blends of PP/PS. In all cases, thermal and oxidative degradation were previously analyzed. Mechanical degradation was found to be the main chain scission mechanism. A negative linear functionality of the chain scission was found in both temperature and polymer concentration. To analyze the relationship between polymer degradation and molecular weight, the chain scission distribution function was calculated. On this basis, a critical molecular weight for the beginning of chain scission was obtained. This value is a function of temperature but remains constant with concentration. © 2007 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 45: 455–465, 2007
Modelling of the ABL and ARG proteins predicts two functionally critical regions that are natively unfolded
Authors: Buffa Pietro , Manzella Livia , Consoli Maria Letizia , Messina Angelo , Vigneri Paolo
Published: January 2007

The ABL and ARG tyrosine kinases regulate many pivotal cellular processes and are implicated in the pathogenesis of several forms of leukemia. We have modelled the previously uncharacterized core domain (SH3‐SH2‐tyrosine kinase) and C‐terminal actin‐binding domain of ARG. We have also investigated the structural arrangement of the ABL and ARG Cap region and of the long multifunctional region located downstream of the tyrosine kinase domain. We report that the ARG core domain is homologous to the corresponding ABL region, therefore suggesting that ARG catalytic activity is likely regulated by the same SH3–SH2 clamp described for ABL. We also report that the Cap of both ABL and ARG is natively unfolded. Hence, biological events determining the folding of the Cap are critical to allow its interaction with the tyrosine kinase C‐lobe. Furthermore, our results show that, with the exception of the C‐terminal actin‐binding domain, the entire region encoded by the ABL and ARG last exon is natively unfolded. Phosphorylation events or protein–protein interactions regulating the folding of this region will therefore modulate the activity of its numerous functional domains. Finally, our analyses show that the C‐terminal actin‐binding domain of ARG displays a four‐helix bundle structure similar to the one reported for the corresponding ABL region. Our findings imply that many biological activities attributed to ABL, ARG, and their oncogenic counterparts are regulated by natively unfolded regions. Proteins 2007. © 2007 Wiley‐Liss, Inc.
Fabrication of SAG‐AlGaN/InGaN/AlGaN LEDs by mixed‐source HVPE with multi‐sliding boat system
Authors: Kim K. H. , Jang K. S. , Hwang S. L. , Jeon H. S. , Choi W. J. , Yang M. , Ahn H. S. , Kim S. W. , Honda Y. , Yamaguchi M. , Sawaki N. , Yoo J. , Lee S. M. , Koike M.
Published: January 2007

The selective area growth (SAG) of AlGaN/InGaN/AlGaN light‐emitting diodes (LEDs) is performed by mixed‐source hydride vapor phase epitaxy (HVPE). In order to obtain the SAG‐AlGaN/InGaN/AlGaN heterostructure, a special graphite fixture to use in HVPE is designed. First, an n‐type AlGaN layer is grown at 1090 °C on a GaN templated (0001) sapphire substrate with a patterned SAG‐structure of a silicon oxide (SiO2). On this selectively grown n‐type AlGaN layer, a nominally undoped‐InGaN layer is grown using an In‐Ga mixed metallic source at 990 °C. After the growth of InGaN layer, Mg‐doped AlGaN and Mg‐doped GaN layers are grown as a cladding and capping layers at 1090 °C and 1050 °C, respectively. All of the epitaxial layers of LED structure are grown consecutively with a multi‐sliding boat system. Room‐temperature electroluminescence (EL) characteristics show an emission peak wavelength of 415 nm with a full width at half‐maximum (FWHM) of approximately 0.37 eV. We find that the mixed‐source HVPE method with multi‐sliding boat system is possible to be one of the growth methods of III‐nitride LEDs. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Analysis of GaN decomposition in an atmospheric MOVPE vertical reactor
Authors: Fathallah W. , Boufaden T. , El Jani B.
Published: January 2007

The GaN decomposition versus the annealing ambient (H2, N2 + H2) have been investigated in atmospheric pressure metal organic vapor phase epitaxy (AP‐MOVPE) vertical reactor. A comparison between the low temperature GaN (LT‐GaN) decomposition in a vertical reactor and a horizontal one was discussed in order to explain the failure of high temperature GaN (HT‐GaN) growth on Al2O3 using 2D buffer layer under a mixture of H2 and N2 in our vertical reactor. Decomposition rates versus temperature and ambient gas were measured using real time laser reflectometry. The surfaces of these films were analyzed using a scanning electron microscopy (SEM). Hydrogen seems to considerably affect the LT‐GaN surface morphology by a mass transport, diffusion on the substrate surface and by a decomposition process even in the presence of ammonia and nitrogen. The high decomposition rates of the LT‐GaN measured in comparison to that determined for the HT‐GaN one is attributed to the amorphous‐like structure of the layer and the instability of Ga‐N bonds. This favors the appearance of a mirror‐like gallium surface in the beginning of this layer decomposition. The presence of liquid gallium catalyzes the decomposition process. HT‐GaN SEM analysis revealed that the surface of the “totally” decomposed GaN surface is dominated by gallium droplets. These were removed. The region around and under these droplets is capped by a porous like GaN film. The coalesced gallium droplets may cover some areas of partially decomposed GaN and preserve them from H2 attack and total decomposition. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Dry etching of N‐face GaN using two high‐density plasma etch techniques
Authors: Rizzi F. , Bejtka K. , Semond F. , Gu E. , Dawson M. D. , Watson I. M. , Martin R. W.
Published: January 2007

This paper describes processing of GaN on the on the (000$ \bar 1 $) N‐face surface, using two different high‐density plasma etch techniques, inductively coupled plasma (ICP) etch, and electron cyclotron resonance (ECR) etching. ICP experiments used several different conditions employing Cl2–Ar–BCl3 or Cl2–Ar plasmas. The resulting maximum etch rates of 370–390 nm/min are approximately twice as high as etch rates for Ga‐face (0001) GaN with the same recipes. ECR etching employed a Cl2–CH4–Ar recipe, which produced an average etch rate of 55 nm/min in a 20‐minute etch process on N‐face GaN. Both etch techniques increased the roughness of N‐face GaN, but could produce surfaces with average roughness values below 3 nm. Selection of conditions with a dominant chemical etch contribution is important to maintain smooth surfaces. The use of both ICP and ECR etching in sequence is advantageous in situations where a GaN substrate several tens of microns in thickness must be thinned from the backside, stopping the etch in a suitable marker layer. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Improvement of surface light extraction from flip‐chip GaN‐based LED by embossing of thermosetting polymers
Authors: Bao Kui , Zhang Bei , Wang ZhiMin , Dai Tao , Kang XiangNing , Chen ZhiZhong , Xu Ke , Ji Hang , Chen Yong , Gan ZiZhao
Published: January 2007

In this report, a further improvement of surface light extraction from flip‐chip GaN‐based LED was obtained by the micro patterning of encapsulation on the sapphire. The two dimensional taper arrays with period from 6 to 10 micron were successfully realized on polymer encapsulation by a simple and low cost technique so called embossing of thermosetting polymers. As a preliminary demonstration, at least 1.74 enhancement of the surface output intensity was achieved in the 1 mm × 1 mm GaN‐based LED device under the injection current of 350 mA. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Focused ion beam etched nitride/air DBRs as cavity mirror facets of violet InGaN/GaN multiple‐quantum well laser diodes
Authors: Dai Tao , Zhang Bei , Zhang ZhenSheng , Xu Jun , Chen WeiHua , Li Rui , Bao Kui , Wei QiYuan , Xu Ke , Hu XiaoDong , Yang ZhiJian , Kang XiangNing , Pan YaoBo , Lu Min , Zhang GuoYi , Gan ZiZhao
Published: January 2007

We report on the demonstration of focused ion beam (FIB) etched nitride/air distributed Bragg reflector (DBR) gratings as cavity mirror facets of violet InGaN/GaN multiple quantum wells edge emitting laser diodes (LD). The nitride/air DBRs consisted of fifth order Bragg semiconductor wall and third order Bragg air gap with the depths around 1.2 micron to 1.5 micron were successfully achieved by focused Ga ion beam (FIB) milling as backside laser facets on GaN‐based laser diodes. Under pulsed current injection at room temperature, sharp laser emissions were observed at the wavelength between 398 to 401 nm. The threshold currents of stripe and ridge lasers with nitride/air DBR mirror facets were found to be respectively lower than the related LDs with cleaved facets. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Cathodoluminescence study of InGaN MQW laser diodes using laser lift‐off technique
Authors: Li Rui , Chen Weihua , Kang Xiangning , Xu Ke , Xu Jun , Yang Zhijian , Nie Ruijuan , Yu Tongjun , Chen Zhizhong , Qin Zhixin , Zhang Guoyi , Gan Zizhao , Hu Xiaodong
Published: January 2007

In this paper, spatially integrated or spatially resolved cathodoluminescence (CL) spectroscopy were employed to evaluate the structural and optical changes of InGaN multiple quantum well (MQW) structure before and after Laser lift‐off (LLO) process. As for a partially strain‐relaxed In0.1Ga0.9N MQW laser diode (LD) structure with cracking in underlying epitaxial layers, LLO did not cause the blue shift in CL spectra as expected, but rather the red shift induced by the indium diffusion from its abundant regions around cracks. This result could be proved by the monochromated scanning CL images taken at 390 nm and 408 nm not having the same obvious complementary as those of original ones. Compared with calculated laser fluence for LLO, this phenomenon could be mainly attributed to the easy penetration of laser energy via cracks and consequent irradiation absorption within MQWs. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
A comparative study of the internal quantum efficiency for the green MQWs grown on sapphire and FS‐GaN substrates
Authors: Jeong Yong‐Hee , Lee Hae‐Yong , Park Jae‐Young , Jeong Jong‐Pil , Hong Chang‐Hee , Suh Eun‐Kyung
Published: January 2007

We observed the green MQWs grown on FS‐GaN substrates leading to less generation of dislocation, V‐defect, and stacking fault than those on sapphire by AFM and TEM. The temperature‐dependent PL spectral peak energies of the green MQWs grown on FS‐GaN substrates reveal more clear “S”‐shaped behaviors due to stronger carrier localization than those on sapphire substrates. Also, the green MQWs grown on FS‐GaN have the higher internal quantum efficiency (IQE) of 9 ∼ 12% in compared to those grown on sapphire at the same MQW thickness and wavelength of 530 ∼ 540 nm. These results will be due to the effects of the enhanced carrier localization and the reduced quantum confined stark effect (QCSE) by reason of the optical‐loss reduction as decreasing the defect density and the piezoelectric field reduction as decreasing the relaxation of strain. We could identify that the green MQWs grown on FS‐GaN substrates have the superior characteristics of the optics, structure, and surface to those on sapphire substrates. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)