bluuebunny/crossref_metadata_2025_split huggingface dataset:
The glass transition in athermal poly(α‐methyl styrene)/oligomer blends
Authors: Zheng Wei , Simon Sindee L. 
Published: December 2007

AbstractThe glass transition behavior in athermal blends of poly(α‐methyl styrene) (PaMS) and its hexamer is investigated using differential scanning calorimetry (DSC). The results, along with previous data on similar blends of PaMS/pentamer, are analyzed in the context of the Lodge–McLeish self‐concentration model. A methodology is described to partition the calorimetric transition to obtain effective Tgs for each component of the blend. The dependences of these effective Tgs on overall blend composition are described by the Lodge–McLeish model, although the self‐concentration effect is less than expected based on the Kuhn length. The length scales of the cooperatively rearranging regions for the two components in the blends are also calculated adapting Donth's fluctuation model to the partitioned DSC transitions and are found to be similar for the two components and show a slight decrease at intermediate concentrations. The kinetics associated with the glass temperature, Tg, is examined by studying the cooling rate dependence of Tg for the pure components and the blends, as well as by examining the enthalpy overshoots in the heating DSC scans. It is observed that the cooling rate dependence of Tg in PaMS/hexamer blends at intermediate concentrations is similar to that of the hexamer, indicating that the kinetics of the glass transition for blends is dominated by the high mobility oligomeric component. Moreover, compared to the pure materials, the PaMS/hexamer blends exhibit a considerably depressed enthalpy overshoot, presumably resulting from their broader relaxation time distribution. © 2008 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 46: 418–430, 2008
Plasma Deposition of Silver Nanoparticles onto Stainless Steel for the Prevention of Fungal Biofilms: A Case Study on Saccharomyces cerevisiae
Authors: Guillemot Gaëlle , Despax Bernard , Raynaud Patrice , Zanna Sandrine , Marcus Philippe , Schmitz Philippe , Mercier‐Bonin Muriel 
Published: December 2007

AbstractA silver nanoparticle composite film was deposited onto stainless steel to reduce the adhesion strength of the model yeast S. cerevisiae. Deposition was carried out under cold‐plasma conditions, combining RF glow discharge and silver sputtering. Shear‐flow‐induced detachment experiments demonstrated the film's anti‐adhesive properties. However, the surface tended to undergo some chemical changes after use, such an increase in hydrophilicity. XPS analysis confirmed the presence of metallic silver for the native plasma‐modified surface and revealed silver oxidation after use. The silver content was also lowered, due to the progressive release of ionic silver from the composite into the medium.magnified image
Interpretation of Light Scattering Spectra of Dispersions – A Hybrid Approach to Account for Interparticle Interactions
Authors: Thennadil Suresh N. , Garcia‐Rubio Luis H. 
Published: December 2007

AbstractThe problem of extracting quantitative information on individual particle properties from spectroscopic measurements conducted at concentrations where particle interactions become significant is of great industrial and theoretical importance. For dispersions of charged particles, this can happen at fairly low concentrations. The effect of the fluid (slurry) structure has to be taken into account to interpret the light scattering spectra of such dispersions. In this paper, a hybrid method that addresses the effect of the fluid structure is proposed. The hybrid approach describes the fluid structure by relating the “effective” Percus‐Yevick hard‐sphere parameters to the system parameters using empirical models. The feasibility of this approach is examined through a theoretical study with data generated by Monte Carlo simulations of a monodisperse dispersion of charged spherical particles using realistic interaction potentials under single scattering conditions.
Particle Size of Pneumatically Conveyed Powders Measured Using Impact Duration
Authors: Coghill Peter J. 
Published: December 2007

AbstractCSIRO Minerals has developed a technique for measuring particle size in pneumatically conveyed powders [1] by measurement of the acoustic waves produced by particle impacts upon a specially designed transducer. Previous work has focused on using the peak acoustic wave amplitude to determine particle size. This produces a spectrum that is hard to determine the particle size from, as the peak amplitude is a non‐linear function of particle diameter, and is strongly affected by angle of incidence and velocity of the impacting particle. In this paper impact duration measurements are used to overcome these difficulties while retaining the advantages of being able to measure in high solids loadings of up to at least 0.5 kg/m3 of powder. In laboratory tests the impact size monitor's (ISM) results have been correlated with optical diffraction measurements of the mean (by number) powder size with a correlation coefficient of 0.985 and a relative error of 5.5 %. The ISM operated successfully in the laboratory at a loading of 0.5 kg/m3 of powder and measured particles down to 50 microns in size.
Computing Particle Surface Areas and Contact Areas from Three‐Dimensional Tomography Data of Particulate Materials
Authors: Thompson Karsten E. 
Published: December 2007

AbstractMicrotomography is an emerging technique for particle and particulate‐materials characterization. To use this technology effectively, robust and accurate computational algorithms are needed to compute relevant particle properties, including particle surface area and particle‐particle contact area. However, the most accurate algorithms that have been developed for computing the exposed (void/solid) surface area in a microtomography image cannot be used directly for computing surface areas or particle‐particle contact areas for individual particles in a dense packing. This paper presents an algorithm for extracting particle contact areas from a digitized, segmented image of a packed granular material, which in turn can be used to find individual particle surface areas (even if the complete surfaces are not exposed because of contacts in the packing). Results show that small errors in the binary surface‐area computations are magnified in the course of determining particle contact areas; the total error in the computation depends mainly on the size of the contact area in voxel units.
Continuous Size Classification of Nanoparticles Utilizing Brownian Motion in Microchannel Size Exclusion Chromatography
Authors: Yamaguchi Tetsuji , Okuyama Kikuo 
Published: December 2007

AbstractThis study presents a new method for classifying the sizes of colloidal nanoparticles of below 100 nm in diameter in liquid dispersion using a microchannel size exclusion chromatography (SEC) chip. This chip can classify polydisperse colloidal nanoparticles containing a mix of two monodisperse nanoparticles into several monodisperse particle populations. The particles classified by the SEC chip are then sequentially analyzed by a photon correlation spectroscopy (PCS) method in combination with a flow cell. Two different pillar patterns of such SEC chips were used in experiments to investigate the effects of these patterns on the nanoparticle classification performance. The results obtained were compared with those from a numerical simulation. Standard polystyrene latex particles with diameters of 20 nm and 100 nm were used in this study. The usefulness of this methodology was verified since the simulation and measurement results were in good agreement with each other.
A Simple Approximate Formula for the Aspect Ratio of Oblate Particles
Authors: Pabst Willi , Berthold Christoph 
Published: December 2007

AbstractA simple approximative formula is derived, which can be used to quantify the shape of oblate particles or an average shape of the corresponding particle system, when the results of sedimentation analysis (Stokes equivalent diameters) are known and results from either microscopic image analysis (assuming stable orientation, i.e., with the plane perpendicular to the direction of observation) or laser diffraction (assuming random orientation) are available for the same sample. In the latter case Cauchy's stereological theorem is applied to account for random orientation. Furthermore, it is shown that for sufficiently large aspect ratios, this formula is very close to the well‐known Jennings‐Parslow relation and can replace this more complicated expression in many practical cases, e.g., in the routine characterization of ceramic raw materials (kaolins and oxide or non‐oxide platelet powders).
Finasteride, prostate cancer, and weight gain: Evidence for genetic or environmental factors that affect cancer outcomes during finasteride treatment
Authors: Song YoonJu , Tangen Catherine , Goodman Phyllis , Parnes Howard L. , Lucia M. Scott , Thompson Ian M. , Kristal Alan R. 
Published: December 2007

AbstractOBJECTIVEFinasteride affects both prostate cancer risk and body weight. We examined whether, during 7 years of finasteride treatment, the magnitude of weight change was associated with the diagnosis of no, low‐, or high‐grade cancer.METHODSData are from 10,057 participants in Prostate Cancer Prevention Trial (PCPT), a randomized trial of finasteride for primary prevention of prostate cancer. Mixed linear models were used to calculate percentage change in weight per year, controlling for demographic and health‐related covariates.RESULTSWeight gain was modestly lower in the finasteride compared to placebo arms (0.14 vs. 0.16% per year, P < 0.025). On the placebo arm, there was no association of weight gain with cancer outcomes. In the finasteride arm, annual weight gain among men without cancer was 0.14%, and among men with cancer ranged from 0.01% for those diagnosed with high‐grade cancer following a clinical indication for biopsy (P = 0.03 vs. no cancer) to 0.25% among men diagnosed with low‐grade cancer at the end of the trial with no indication for biopsy (P = 0.002 vs. no cancer).CONCLUSIONSIn finasteride‐treated men, there are significant associations between prostate cancer outcomes and weight gain, which suggest that there are common or closely related individual‐level factors that affect both treatment responses. This supports the hypothesis that there are genetic characteristics and/or environmental exposures that affect finasteride outcomes which, when identified, could be used to target men most likely to benefit from finasteride treatment. Prostate 68: 281–286, 2008. © 2007 Wiley‐Liss, Inc.
A molecular analysis of prokaryotic and viral DNA sequences in prostate tissue from patients with prostate cancer indicates the presence of multiple and diverse microorganisms
Authors: Sfanos Karen S. , Sauvageot Jurga , Fedor Helen L. , Dick James D. , De Marzo Angelo M. , Isaacs William B. 
Published: December 2007

AbstractBACKGROUNDInflammation, both acute and chronic, is a common feature of prostate histology. While inflammation has been proposed to play an important role in both benign and malignant growth of the prostate, the stimuli for this inflammation remain poorly characterized. Infectious pathogens are potential stimuli for prostatic inflammation.METHODSUniversal eubacterial PCR was used to test 170 prostate tissue core samples from 30 cancer patients for 16S rDNA gene sequences. Positive PCR products (n = 64, 37%) were cloned and sequenced. For comparison, tissue samples from 30 patients were cultured using standard clinical microbiological techniques. DNA samples from 200 additional patients were tested by organism‐specific PCR for the presence of Chlamydia trachomatis, Propionibacterium acnes, Trichomonas vaginalis, BK virus, Epstein–Barr virus, human cytomegalovirus, human papillomavirus, and xenotropic murine leukemia‐related virus.RESULTS16S sequencing results indicated the presence of 83 distinct microorganisms. Microbiological culture isolated markedly fewer species. In general, organism‐specific PCR failed to detect multiple organisms previously reported as common in the prostate. There was no significant association between the presence of particular species of bacteria and histologic evidence of acute or chronic inflammation.CONCLUSIONSMost prostates from men undergoing prostatectomy (87%) contain bacterial DNA from one or more species. However, the majority of individual tissue core samples were negative, suggesting regional heterogeneity in the presence of bacteria and a lack of a generalized or ubiquitous prostatic flora. Culture results suggest either the “unculturable” nature of species present in the prostate or that 16S rDNA sequences were derived from non‐viable bacteria. Prostate 68: 306–320, 2008. © 2007 Wiley‐Liss, Inc.
The Glu228Ala polymorphism in the ligand binding domain of death receptor 4 is associated with increased risk for prostate cancer metastases
Authors: Langsenlehner Tanja , Langsenlehner Uwe , Renner Wilfried , Kapp Karin S. , Krippl Peter , Hofmann Günter , Clar Heimo , Pummer Karl , Mayer Ramona 
Published: December 2007

AbstractBackgroundDeath receptor 4, encoded by the TNFRSF10A gene, is an important mediator of apoptosis and its dysfunction may be related to cancer development and distant tumor spread. A single nucleotide polymorphism in TNFRSF10A (Glu228Ala, rs20576) within a conserved region of the extracellular cysteine‐rich domain of death receptor 4 has been associated with an increased risk for a variety of tumor entities. Aim of the present study was to evaluate the role of the TNFRSF10A polymorphism in metastatic progression of prostate cancer after radiation therapy.MethodsWe carried out a prospective study including 702 prostate cancer patients from the Austrian PROCAGENE (Prostate Cancer Genetics) study. Development of metastases was examined in regular follow‐up investigations. TNFRSF10A genotypes were determined by a 5′‐nuclease assay (TaqMan).ResultsWithin a median follow‐up time of 10 months (range 0–60 months), 24 (3.4%) patients developed metastases. In a Cox regression model including age at diagnosis and risk group as potential confounders, carriage of an 228Ala allele was associated with a relative risk of 2.47 (95% CI 1.10–5.54; P = 0.028) for metastases. TNFRSF10A genotypes were not associated with tumor stage, grade, risk group or age at diagnosis.ConclusionWe conclude that the TNFRSF10A Glu228Ala polymorphism may be a novel independent risk factor for prostate cancer metastases after radiation therapy. Prostate 68: 264–268, 2008. © Wiley‐Liss, Inc.
TGF‐β signaling and androgen receptor status determine apoptotic cross‐talk in human prostate cancer cells
Authors: Zhu Meng‐Lei , Partin James V. , Bruckheimer Elizabeth M. , Strup Stephen E. , Kyprianou Natasha 
Published: December 2007

AbstractBACKGROUNDA signaling interaction between transforming growth factor‐β (TGF‐β) and androgens promotes apoptosis in human prostate cancer cells LNCaP‐TβRII (androgen‐sensitive and TGF‐β responsive). This study investigated the contribution of androgen receptor (AR) in the combined effect of TGF‐β and dihydrotestosterone (DHT), on regulation of apoptosis and AR‐ and TGF‐β mediated transcriptional activity in human prostate cancer cells.METHODSTranscriptional activation in response to TGF‐β (5 ng/ml) and DHT (1 nM) was evaluated using transient transfections and luciferase assays in human prostate cancer cells, LNCaP‐TβRII and PC‐3, overexpressing the wild type AR. The apoptotic response to DHT/TGFβ treatment was correlated with AR cellular distribution and the AR interaction with TGF‐β intracellular effector Smad4.RESULTSThe results revealed that TGF‐β signaling induced AR‐mediated transcriptional activation in two androgen‐responsive promoters [probasin and prostate specific antigen (PSA)]. TGF‐β1 induced transcriptional activity enhanced by DHT in both cell lines (LNCaP‐TβRII and PC‐3‐AR) via AR‐Smad4 interaction. This interaction however does not exclusively drive TGF‐β mediated apoptosis as DHT failed to enhance such an effect in PC‐3 AR (wt) cells.CONCLUSIONSThese results demonstrate that the AR status determines the sensitivity of prostate cancer cells to the apoptotic effects of TGF‐β1, thus providing a new insight into the mechanism via which TGF‐β cross‐sections the AR axis toward the functional convergence of the two pathways in the development of androgen‐independent prostate cancer. This study is potentially significant in defining the contribution of AR status to the emergence of androgen‐independent prostate tumors. Prostate 68: 287–295, 2008. © 2007 Wiley‐Liss, Inc.
Galiellalactone is a novel therapeutic candidate against hormone‐refractory prostate cancer expressing activated Stat3
Authors: Hellsten Rebecka , Johansson Martin , Dahlman Anna , Dizeyi Nishtman , Sterner Olov , Bjartell Anders 
Published: December 2007

AbstractBACKGROUNDSignal transducer and activator of transcription 3 (Stat3) is constitutively active (phosphorylated) in several forms of cancer, including prostate cancer (PCa). Stat3 signaling may be an interesting target for cancer therapy since inhibition of this pathway mediates growth inhibition and apoptosis of these cells. In this study we investigated the in vitro and in vivo effects of the fungal metabolite galiellalactone, a direct inhibitor of Stat3, on PCa cells.METHODSThe human PCa cell lines DU145, PC‐3, and LNCaP were used. Nude mice with subcutaneous PCa cell xenografts were subjected to daily intraperitoneal injections of galiellalactone for 3 weeks. The effect of galiellalactone on the induction of apoptosis of cultured PCa cells was investigated by Western blot analysis, immunocytochemistry, and annexin V staining. Effects of galiellalactone on Stat3 signaling were investigated by a luciferase reporter gene assay. Expression of Stat3 associated proteins and mRNA was investigated by Western blot and real‐time quantitative PCR analysis.RESULTSGaliellalactone induced apoptosis of p‐Stat3 positive PCa cells (androgen‐insensitive DU145 and PC‐3) but not in cells lacking p‐Stat3 (androgen‐sensitive LNCaP). Galiellalactone inhibited Stat3‐mediated luciferase activity (IC50 ∼ 5 µM) and reduced the expression of Bcl‐2, Bcl‐xL, c‐myc, and cyclin D1. Furthermore, galiellalactone significantly suppressed DU145 xenograft growth in vivo (42% growth reduction; P < 0.002) and reduced the relative mRNA expression of Bcl‐xL and Mcl‐1.CONCLUSIONSGaliellalactone induced growth inhibition and apoptosis in androgen‐insensitive PCa cells expressing p‐Stat3. We suggest that galiellalactone is a potential anti‐tumor lead against hormone‐refractory PCa with constitutively active Stat3. Prostate 68: 269–280, 2008. © 2007 Wiley‐Liss, Inc.
Expression of BNIP3 correlates with hypoxia‐inducible factor (HIF)‐1α, HIF‐2α and the androgen receptor in prostate cancer and is regulated directly by hypoxia but not androgens in cell lines
Authors: Shaida Nadeem , Launchbury Rosalind , Boddy Jane L. , Jones Catherine , Campo Leticia , Turley Helen , Kanga Suresh , Banham Alison H. , Malone Peter R. , Harris Adrian L. , Fox Stephen B. 
Published: December 2007

AbstractBackgroundBNIP3 is a hypoxia‐induced protein involved in cell death and survival but its role in human tumors is unclear. This study investigated the role of BNIP3 in prostate cancer.MethodsThe expression of BNIP3, the androgen receptor (AR), hypoxia inducible factor (HIF)‐1α, HIF‐2α and the hypoxia regulated gene GLUT1 were assessed in tissue microarrays constructed from 149 radical prostatectomy specimens. Statistics compared expression of these factors between each other, conventional clinicopathological parameters and PSA recurrence. Since an association between BNIP3 and AR and the HIFs was observed, the influence of hypoxia, dihydrotestosterone and the AR blocker, Casodex, was also investigated in prostate cell lines.ResultsBNIP3 was expressed in the nucleus and cytoplasm. Eight of 149 (5.5%) tumors showed no expression, 44/149 (29.5%) cases showed exclusively cytoplasmic expression, 17/149 (11.5%) cases showed exclusively nuclear expression and 80/149 (53.5%) cases showed both cytoplasmic and nuclear expression. There was a significant correlation between cytoplasmic BNIP3 expression and Gleason score (P = 0.005), age (P = 0.02), AR (P = 0.001), and GLUT1 (P = 0.006). There was a significant correlation between nuclear BNIP3 expression and HIF‐1α expression (P = 0.006) and HIF‐2α expression (P = 0.013) but no correlation between BNIP3 and pre‐operative PSA, tumor volume, margin positivity or capsular invasion (all P > 0.05). There was an increase in BNIP3 expression under conditions of hypoxia (0.1% 02) but not with dihydrotestosterone stimulation or with Casodex treatment.ConclusionsThese findings suggest that BNIP3 is directly regulated by hypoxia but that there may be a hormonal independent mechanism coordinating the expression of BNIP3 in prostate tumors. Prostate 68: 336–343, 2008. © Wiley‐Liss, Inc.
Abatacept: first T cell co‐stimulation modulator for severe active RA
Authors: Chaplin Steve , Ostor Andrew 
Published: December 2007

AbstractAbatacept (Orencia) is licensed for the treatment of severe RA in combination with methotrexate when at least one anti‐TNF agent has failed. Here, Steve Chaplin presents the clinical data relating to its efficacy and adverse effects, and Dr Andrew Ostor comments on its place in RA therapy. Copyright © 2007 Wiley Interface Ltd
Grape seed extract treatment reduces hepatic ischemia‐reperfusion injury in rats
Authors: Şehirli Özer , Ozel Yahya , Dulundu Ender , Topaloglu Umit , Ercan Feriha , Şener Goksel 
Published: December 2007

AbstractThis study was designed to determine the possible protective effect of grape seed extract (GSE), a widely used antioxidant dietary supplement, on hepatic ischemia/reperfusion (I/R) injury. Wistar albino rats were subjected to 45 min of hepatic ischemia, followed by a 60 min reperfusion period. GSE was administered in a dose of 50 mg/kg/day orally for 15 days before I/R injury and repeated before the reperfusion period. Liver samples were taken for histological examination or determination of hepatic malondialdehyde (MDA), glutathione (GSH) and myeloperoxidase (MPO) activity. Serum aspartate aminotransferase (AST) and alanine aminotransferase (ALT) levels were determined to assess liver functions. Lactate dehydrogenase (LDH) and cytokines (TNF‐α and IL‐1β) were also assayed in serum samples for the evaluation of generalized tissue damage. Ischemia/reperfusion caused a significant decrease in hepatic GSH, and significant increases in MDA level, and MPO activity. Serum AST and ALT levels, as well as LDH activity and plasma TNF‐α and IL‐1β levels were also elevated in the I/R group. Treatment with GSE reversed all these biochemical parameters as well as histological alterations induced by I/R. In conclusion, GSE reduced I/R‐induced organ injury through its ability to balance the oxidant–antioxidant status, to inhibit neutrophil infiltration and to regulate the release of inflammatory mediators. Copyright © 2007 John Wiley & Sons, Ltd.