bluuebunny/crossref_metadata_2025_split huggingface dataset:
Antibiotic use predicts an increased risk of cancer
Authors: Kilkkinen Annamari , Rissanen Harri , Klaukka Timo , Pukkala Eero , Heliövaara Markku , Huovinen Pentti , Männistö Satu , Aromaa Arpo , Knekt Paul 
Published: August 2008

AbstractAntibiotic use has been hypothesized to be associated with the risk of cancer but the evidence is sparse and inconsistent. The aim of the present study was to determine whether antibiotic use predicts the development of various cancers. This nationwide cohort study included 3,112,624 individuals, aged 30–79 years, with no history of cancer. Information on their antibiotic use between 1995 and 1997 was obtained from the Drug Prescription Registry. During the period 1998–2004, 134,070 cancer cases were ascertained from the Finnish Cancer Registry. Cox proportional hazards regression was used to estimate the relative risks (RRs) with 95% confidence intervals (95% CIs). Antibiotic use was associated with an increased risk of cancer: for categories of increasing antibiotic use (0–1, 2–5 and ≥6 prescriptions), RRs (95% CIs) for cancer were 1.0 (reference), 1.27 (1.26–1.29) and 1.37 (1.34–1.40). RRs (for comparison of lowest and highest exposure group) for the most common primary sites i.e. prostate, breast, lung and colon were 1.39 (1.31–1.48), 1.14 (1.09–1.20), 1.79 (1.67–1.92), and 1.15 (1.04–1.26), respectively. RRs for other primary sites varied between 0.90 (0.76–1.05) for ovary to 2.60 (1.60–4.20) for endocrine gland (excluding thyroid). In conclusion, antibiotic use predicts an increased risk of cancer. Because of the design of our study the possibility of residual confounding cannot be excluded and further studies are required to confirm the results. © 2008 Wiley‐Liss, Inc.
Evidence for a pathophysiological role of cysteinyl leukotrienes in classical Hodgkin lymphoma
Authors: Schain Frida , Tryselius Ylva , Sjöberg Jan , Porwit Anna , Backman Linda , Malec Maria , Xu Dawei , Vockerodt Martina , Baumforth Karl R.N. , Wei Wenbin , Murray Paul G. , Björkholm Magnus , Claesson Hans‐Erik 
Published: August 2008

AbstractClassical Hodgkin lymphoma (cHL) is characterized histologically by a minority of malignant Hodgkin Reed‐Sternberg cells surrounded by abundant inflammatory cells, generally believed to be of major importance in the pathophysiology of the disease. Here, we present data that link inflammatory cell‐derived arachidonic acid metabolites, the cysteinyl leukotrienes (CysLT), to the pathogenesis of cHL. Two HL cell lines, L1236 and KMH2, were shown to express functional CysLT1 receptors, responding with a robust calcium signal upon leukotriene (LT) D4 challenge. LTD4 stimulated protein release of tumor necrosis factor‐α, interleukin‐6 and ‐8 by L1236 cells and interleukin‐8 by KMH2 cells. Importantly, all these LTD4‐induced effects were blocked by the CysLT1 receptor‐specific antagonist zafirlukast. Immunohistochemical studies of cHL biopsies and microarray analysis of microdissected cells revealed that the CysLT1 receptor is expressed also by primary Hodgkin Reed‐Sternberg cells. As these cells are surrounded by CysLT‐producing eosinophils, macrophages and mast cells, our results suggest the CysLTs as mediators in the pathogenesis of cHL, contributing to the aberrant cytokine network of this lymphoma. © 2008 Wiley‐Liss, Inc.
Activated carbons from peach stones and pine sawdust by phosphoric acid activation used in clarification and decolorization processes
Authors: Muñoz‐González Yuvisa , Arriagada‐Acuña Renán , Soto‐Garrido G , García‐Lovera Rafael 
Published: August 2008

AbstractBACKGROUND: A comparative study of the influence of preparation variables in the activation of pine sawdust and peach stones with phosphoric acid is presented. Adsorptive properties of these materials were tested for the clarification of apple juice and the decolorization of red wine. The main objective of this study was to identify the influence of the textural and chemical properties of activated carbons on clarification and decolorization processes.RESULTS: The role of impregnation conditions in porosity development was more important for activated carbons originating from peach stones than in those originating from pine sawdust, mainly due to their morphological differences. The amount of phosphoric acid retained on the precursors was found to be a function of the impregnation variables. Furthermore, porosity development dependence on phosphoric acid content per gram of precursor was confirmed. For both precursors, the best microporosity development was obtained at a heat treatment temperature of 450 °C. Independently of the preparation variables used, activated carbons from pine sawdust and peach stones had the same type of surface functional groups: mainly phenolic, quinonic and phosphoric ester‐like structures.CONCLUSIONS: From the results of clarifications and decolorization tests, it was confirmed that to obtain good performance in these assays, the development of mesoporosity is crucial. However, when activated carbons had similar mesoporosities, the presence of surface functional groups contributed to improved performance in clarification and decolorization process. Copyright © 2008 Society of Chemical Industry
Too big to bind? Will the purification of large and complex therapeutic targets spell the beginning of the end for column chromatography?
Authors: Willoughby Nik 
Published: August 2008

AbstractProgress in some areas of medical research is leading to larger and more complex therapeutic products—for example, cellular or gene therapies. For decades, the bioprocessing industry has relied upon column chromatography as the mainstay of purification processes. Whilst highly effective for the purification of proteins and smaller molecules, chromatographic techniques are not necessarily well suited to purification of these newer, larger targets. This article considers the approaches adopted in the purification of large, complex targets and emphasises the need for more focused development of purification techniques more suited to the target's size and complexity. Copyright © 2008 Society of Chemical Industry
Octanol/water partition coefficients of ionic liquids
Authors: Lee Sang Hyun , Lee Sun Bok 
Published: August 2008

AbstractBACKGROUND: Room temperature ionic liquids (ILs) are attractive alternatives to environmentally unfriendly volatile organic solvents. Partitioning is one of the most important and fundamental properties of a chemical, and the octanol/water partition coefficient is widely used to measure the tendency of a chemical to cross biological membranes. However, there is very limited information on the concentration dependence of the partition coefficients of ILs. This study investigated the octanol/water partitioning of 1‐butyl‐3‐methylimidazolium ([bmim]) ILs containing either hexafluorophosphate ([PF6]) or bis[(trifluoromethyl)sulfonyl]amide ([Tf2N]) over a wide range of IL concentrations of three to five orders of magnitude.RESULTS: It was found that the apparent partition coefficients of the ILs increased with increasing IL concentration. A model based on the ionic nature of ILs was proposed to explain this behaviour, and the results showed a good fit with the experimental data. The intrinsic partition coefficients and dissociation constants of the ILs were determined using the equations from the proposed model. The differences in the intrinsic partition parameter values between the two ILs showed a good correlation with other physicochemical properties.CONCLUSIONS: The present study clearly shows that the octanol/water partition coefficients of ILs increase with increasing IL concentration owing to the formation of ion pairs. By using the proposed partition model, it was possible to determine the intrinsic partition coefficients of ILs, and it was found that the apparent partition coefficients of ILs converge to the intrinsic partition coefficients of the ionic species and ion pairs of ILs with decreasing and increasing IL concentration respectively. Copyright © 2008 Society of Chemical Industry
Sand dune fixation: A solar‐powered Sahara seawater pipeline macroproject
Authors: Badescu V. , Cathcart R. B. , Bolonkin A. A. 
Published: August 2008

AbstractThe paper proposes macro‐engineering using tactical technologies that stabilize and vegetate barren near‐coast sand dune fields with seawater. Seawater that would otherwise, as commonly postulated, increase the Earth–ocean volume. Anthropogenic saturation of the ground with pumped seawater should fix widespread active sand dune fields in deserts (such as the westernmost Sahara). Seawater extraction from the ocean, and its deposition on dune sand, is made via solar‐powered pipeline. Stabilisation of one major erg in Mauritania is evaluated as a case study. The financial cost of the macroproject is estimated as a few billion US$—less than about 0·1 per cent of the USA's 2007 gross domestic product. The initial investment may be between 0·6 and 1·1 billions US$. Copyright © 2008 John Wiley & Sons, Ltd.
Non‐Bioengineered Silk Fibroin Protein 3D Scaffolds for Potential Biotechnological and Tissue Engineering Applications
Authors: Mandal Biman B. , Kundu Subhas C. 
Published: August 2008

AbstractThis paper describes a new source for fabricating high‐strength, non‐bioengineered silk gland fibroin 3D scaffolds from Indian tropical tasar silkworm, Antheraea mylitta using SDS for dissolution. The scaffolds were fabricated by freeze drying at different prefreezing temperatures for pore size and porosity optimization. Superior mechanical properties with compressive strength in the range of 972 kPa were observed. The matrices were degraded by proteases within 28 d of incubation. Biocompatibility was assessed by feline fibroblast culture in vitro and confocal microscopy further confirmed adherence, spreading, and proliferation of primary dermal fibroblasts. Results indicate nonmulberry 3D silk gland fibroin protein as an inexpensive, high‐strength, slow biodegradable, biocompatible, and alternative natural biomaterial.magnified image
Room Temperature Processable Silicon‐Containing Molecular Resist
Authors: Park Ji Young , Kim Myung Gi , Kim Jin‐Baek 
Published: August 2008

AbstractA novel silicon‐containing molecular resist material based on polyhedral oligomeric silsesquioxane, possessing trimethoxysilyl groups, was designed in order to reduce post‐exposure delay problems and to improve resolution. Since the acid‐catalyzed cross‐linking reaction of trimethoxysilyl groups occurs at room temperature, there is no necessity of post‐exposure bake. The molecular resist showed 0.7 µm line‐and‐space patterns using a mercury–xenon lamp in a contact printing mode and 100 nm line‐and‐space patterns using electron beam lithography.magnified image
Ring Opening Polymerization of Lactide under Solvent‐Free Conditions Catalyzed by a Chlorotitanium Calix[4]arene Complex
Authors: Frediani Marco , Sémeril David , Mariotti Alfredo , Rosi Luca , Frediani Piero , Rosi Laura , Matt Dominique , Toupet Loïc 
Published: August 2008

AbstractA novel chlorotitanium calix[4]arene complex was synthesized and tested, without activator, as catalyst for the polymerization of L‐ and rac‐lactide under solvent‐free conditions. The catalyst displayed high activity, which depended on the monomer‐to‐catalyst molar ratio, and led to highly isotactic PLLA. Despite concomitant transesterification during the polymerization, polylactide formation was well‐controlled, the molar mass distribution indexes remaining in the restricted range of 1.2–1.4.magnified image
Synthesis and characterization of PbS/polyaniline core–shell nanocomposites based on octahedral PbS nanocrystals colloid
Authors: Jing Shengyu , Xing Shuangxi , Dong Fengxia , Zhao Chun 
Published: August 2008

AbstractPbS/polyaniline core–shell nanocomposites were successfully synthesized via in situ chemical oxidation polymerization of aniline based on the octahedral PbS nanocrystals colloid. The morphology and structure of the products were characterized by transmission electron microscopy, X‐ray diffraction, Fourier transform infrared spectra, UV–vis spectra, and conductivity measurement. A possible formation mechanism of the PbS/polyaniline core–shell nanocomposites was also proposed. POLYM. COMPOS., 2008. © 2008 Society of Plastics Engineers
Modelling of the chemo–rheological behavior of thermosetting polymer nanocomposites
Authors: Lelli Govanni , Terenzi Andrea , Kenny Jose M. , Torre Luigi 
Published: August 2008

AbstractEpoxy/amine/montmorillonite nanocomposite systems are studied in this article. Both a thermo−kinetic analysis (performed using a differential scanning calorimeter) and a chemorheological characterization were carried out. The comparison of DSC thermograms has shown that the addition the nanofiller does not change the mechanism of crosslinking from a qualitative standpoint, but the nanoreinforcement seemed to produce an evident hindrance on the molecular mobility, which in turn influences the cure reactions. As none of the kinetic models available in literature was able to describe the cure behavior of the aforementioned materials, a new phenomenological model is proposed in this work, which considers the activation energy of the networking process a function of the degree of cure (rising exponentially towards infinity when thesystem approaches vitrification). The effects of the presence of the clay on the chemorheology of the composites was resumed as follows: the viscosity of the nanocomposite was higher at any temperature, furthermore the composite viscosity showed an higher heating sensitivity before networking and gelation occurred at lower degrees of cure, thus determining a narrower shape of the chemoviscosity behavior. A modified version of the classical Williams–Landel–Ferry (WLF) equation that took into account the gelation and the effects of crosslinking was uses as chemorheological model. Once the characteristic parameters of both the neat resin and the nanocomposite were found, the chemoviscosity models were integrated using a numerical algorithm, to check their ability to foresee the behavior of the systems during a dynamic cure process. A very good correspondence between the results and the experimental data was obtained. POLYM. COMPOS., 2009. © 2008 Society of Plastics Engineers
Preparation of the γ‐Al2O3/PANI nanocomposite via enzymatic polymerization
Authors: Nabid Mohammad Reza , Golbabaee Maryam , Moghaddam Abdolmajid Bayandori , Mahdavian Ali Reza , Amini Mostafa Mohammadpour 
Published: August 2008

AbstractPeroxidase‐catalyzed template‐guided polymerization of aniline in the presence of γ‐ alumina nanosheet (NS) particles have been carried out in aqueous media and γ‐Al2O3/PANI nanocomposite was obtained. The polymerization of aniline occurred in aqueous solution in the presence of SPS (sulfonated polystyrene) as a template and SDS (sodium dodecyl sulfate) as a surfactant. Both obtained nanocomposites were comparable by SEM images. It was demonstrated that the γ‐Al2O3 NS/PANI‐SPS nanocomposite has higher conductivity and the γ‐Al2O3 NS/PANI‐SDS nanocomposite has higher void areas. The higher conductivity of γ‐Al2O3 NS/PANI‐SPS nanocomposite is attributed to the higher coated areas of γ‐Al2O3 NS during polymerization in comparison with γ‐Al2O3 NS/PANI‐SDS which are not coated efficiently as the former. The FT‐IR studies showed that the γ‐Al2O3 NS/PANI nanocomposite was formed by interaction of the polyaniline (PANI) and γ‐Al2O3 NS. FTIR also showed that the amount of PANI in γ‐Al2O3 NS/PANI‐SPS is more than in γ‐Al2O3 NS/PANI‐SDS. POLYM. COMPOS., 2009. © 2008 Society of Plastics Engineers
Tensile creep of a long‐fibre glass mat thermoplastic (GMT) composite. II. Viscoelastic‐viscoplastic constitutive modeling
Authors: Dasappa Prasad , Lee‐Sullivan Pearl , Xiao Xinran , Foss Peter H. 
Published: August 2008

AbstractIn Part I of this article, the short‐term tensile creep of a 3‐mm‐thick continuous long‐fibre glass mat thermoplastic composite was characterized and found to be linear viscoelastic up to 20 MPa. Subsequently, a nonlinear viscoelastic model has been developed for stresses up to 60 MPa for relatively short creep durations. The creep response was also compared with the same composite material having twice the thickness for a lower stress range. Here in Part II, the work has been extended to characterize and model longer term creep and recovery in the 3‐mm composite for stresses up to near failure. Long‐term creep tests consisting of 1‐day loading followed by recovery were carried out in the nonlinear viscoelastic stress range of the material, i.e., 20–80 MPa in increments of 10 MPa. The material exhibited tertiary creep at 80 MPa and hence data up‐to 70 MPa has been used for model development. It was found that viscoplastic strains of about 10% of the instantaneous strains were developed under load. Hence, a non‐linear viscoelastic–viscoplastic constitutive model has been developed to represent the considerable plastic strains for the long‐term tests. Findley's model which is the reduced form of the Schapery non‐linear viscoelastic model was found to be sufficient to model the viscoelastic behavior. The viscoplastic strains were modeled using the Zapas and Crissman viscoplastic model. A parameter estimation method which isolates the viscoelastic component from the viscoplastic part of the nonlinear model has been developed. The model predictions were found to be in good agreement with the average experimental curves. POLYM. COMPOS., 2009. © 2008 Society of Plastics Engineers
Protein unlocking procedures of formalin‐fixed paraffin‐embedded tissues: Application to MALDI‐TOF Imaging MS investigations
Authors: Ronci Maurizio , Bonanno Elena , Colantoni Alfredo , Pieroni Luisa , Di Ilio Carmine , Spagnoli Luigi Giusto , Federici Giorgio , Urbani Andrea 
Published: August 2008

AbstractArchival formalin‐fixed paraffin‐embedded (FFPE) tissues are a powerful tool for examining the clinical course of diseases. These specimens represent an incredible mine of valuable clinical and biological information for proteomic investigation. MALDI‐TOF imaging MS (MALDI‐IMS) is a protein profiling technique which enables the direct sampling of histological section; however, the quality of molecular data are strongly influenced by the tissue preparation condition. In fact, in previous years most of the studies employing such a technological platform have been conducted using cryo‐preserved tissues. We have developed an in vitro approach using “tissue surrogate” samples in order to explore different protein unlocking procedures which might enable a suitable recovery of polypeptides for MS analysis. The developed protocols have been compared both by MALDI‐TOF MS and nLC‐MSE analysis either on surrogate samples or on FFPE specimen from human breast cancer. The collected evidence has been applied for the preparation of FFPE tissue sections following MALDI‐IMS analysis. Our results outline the possibility to obtain valuable peptide mass spectra profiles form FFPE preparations by applying a combined two steps procedure of heat induced antigen retrieval (HIAR) in presence of EDTA and on target trypsin hydrolysis. A multivariate statistical evaluation is presented and discussed according to molecular spatial distributions and tissue morphology.
Analysis of nonadditive protein accumulation in young primary roots of a maize (Zea mays L.) F1‐hybrid compared to its parental inbred lines
Authors: Hoecker Nadine , Lamkemeyer Tobias , Sarholz Barbara , Paschold Anja , Fladerer Claudia , Madlung Johannes , Wurster Karl , Stahl Mark , Piepho Hans‐Peter , Nordheim Alfred , Hochholdinger Frank 
Published: August 2008

AbstractHeterosis describes the superior performance of heterozygous F1‐hybrids compared to their homozygous parental inbred lines. Heterosis is already manifested during early maize (Zea mays L.) primary root development. In this study, the most abundant soluble proteins have been investigated before the phenotypic manifestation of heterosis in 3.5‐day‐old primary roots in the flint inbred line UH002, the dent inbred line UH301 and the corresponding hybrid UH301×UH002. In CBB‐stained 2‐DE gels, 150 of 304 detected proteins (49%) were accumulated in a nonadditive fashion in the hybrid compared to the average of their parental inbred lines (Student's t‐test: p < 0.05). Remarkably, expression of 51% (76/150) of the nonadditively accumulated proteins exceeded the high parent or was below the low parent. ESI‐MS/MS identified 75 of the 76 proteins that belonged to these expression classes. The most abundant functional classes among the 75 proteins that were encoded by 60 different genes were metabolism (58%) and disease and defense (19%). Nonadditive protein accumulation in primary roots of maize hybrids might be associated with heterosis manifestation. Identification of these proteins could therefore contribute to the better understanding of the molecular basis of heterosis.
X‐ray structure of HIV‐1 protease in situ product complex
Authors: Bihani Subhash , Das Amit , Prashar Vishal , Ferrer J.‐L. , Hosur M. V. 
Published: August 2008

AbstractHIV‐1 protease is an effective target for design of different types of drugs against AIDS. HIV‐1 protease is also one of the few enzymes that can cleave substrates containing both proline and nonproline residues at the cleavage site. We report here the first structure of HIV‐1 protease complexed with the product peptides SQNY and PIV derived by in situ cleavage of the oligopeptide substrate SQNYPIV, within the crystals. In the structure, refined against 2.0‐Å resolution synchrotron data, a carboxyl oxygen of SQNY is hydrogen‐bonded with the N‐terminal nitrogen atom of PIV. At the same time, this proline nitrogen atom does not form any hydrogen bond with catalytic aspartates. These two observations suggest that the protonation of scissile nitrogen, during peptide bond cleavage, is by a gem‐hydroxyl of the tetrahedral intermediate rather than by a catalytic aspartic acid. Proteins 2009. © 2008 Wiley‐Liss, Inc.
Structural coupling between FKBP12 and buried water
Authors: Szep Szilvia , Park Sheldon , Boder Eric T. , Van Duyne Gregory D. , Saven Jeffery G. 
Published: August 2008

AbstractGlobular proteins often contain structurally well‐resolved internal water molecules. Previously, we reported results from a molecular dynamics study that suggested that buried water (Wat3) may play a role in modulating the structure of the FK506 binding protein‐12 (FKBP12) (Park and Saven, Proteins 2005; 60:450–463). In particular, simulations suggested that disrupting a hydrogen bond to Wat3 by mutating E60 to either A or Q would cause a structural perturbation involving the distant W59 side chain, which rotates to a new conformation in response to the mutation. This effectively remodels the ligand‐binding pocket, as the side chain in the new conformation is likely to clash with bound FK506. To test whether the protein structure is in effect modulated by the binding of a buried water in the distance, we determined high‐resolution (0.92–1.29 Å) structures of wild‐type FKBP12 and its two mutants (E60A, E60Q) by X‐ray crystallography. The structures of mutant FKBP12 show that the ligand‐binding pocket is indeed remodeled as predicted by the substitution at position 60, even though the water molecule does not directly interact with any of the amino acids of the binding pocket. Thus, these structures support the view that buried water molecules constitute an integral, noncovalent component of the protein structure. Additionally, this study provides an example in which predictions from molecular dynamics simulations are experimentally validated with atomic precision, thus showing that the structural features of protein–water interactions can be reliably modeled at a molecular level. Proteins 2009. © 2008 Wiley‐Liss, Inc.