bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effect of GnRH analogs on the expression of TrkA and p75 neurotrophin receptors in primary cell cultures from human prostate adenocarcinoma
Authors: Sánchez Catherine , Clementi Marisa , Benitez Dixan , Contreras Héctor , Huidobro Christian , Castellón Enrique 
Published: June 2005

AbstractBACKGROUNDGnRH analogs have antiproliferative and/or apoptotic effects on prostate cancer cells. Also, neurotrophin receptors TrkA and p75 have been reported in normal prostate suggesting a role in the gland growth control. In prostate cancer, TrkA receptors seem to be overexpressed and p75 receptors show a decreased expression. These changes in neurotrophin receptors may be related with unbalanced growth in malignant cells. In the present study we investigate the effects of GnRH analogs (leuprolide and cetrorelix) on the expression of TrkA and p75 neurotrophin receptors in primary cultures of human prostate cancer cells.METHODSTissue was obtained from radical prostatectomies due to prostate adenocarcinoma. Cells were isolated after sequential enzyme digestion and cultured in defined media. Nerve growth factor (NGF) receptors in untreated cultures were estimated by immunofluorescence. Cultures were treated with leuprolide (agonist) or cetrorelix (antagonist) and expression of TrkA and p75 receptors were evaluated by semi quantitative RT‐PCR (polymerase chain reaction) and western blot. Cell proliferation was estimated by MTT method and apoptosis through COMET assay.RESULTSBoth leuprolide and cetrorelix induced a significant increase in p75 receptor gene and protein expression at a concentration that induce apoptosis and decrease proliferation. TrkA receptors showed no changes in presence of GnRH analogs.CONCLUSIONSGnRH analogs, leuprolide, and cetrorelix, change the ratio between neurotrophin receptors TrkA and p75 by increasing gene and protein expression of p75 receptor. Considering that TrkA receptor is related with proliferation and p75 with apoptosis, we suggest that our findings may explain, in part, the effect of GnRH analogs on prostate cancer growth. © 2005 Wiley‐Liss, Inc.
Dual inhibition of the epidermal growth factor and vascular endothelial growth factor phosphorylation for antivascular therapy of human prostate cancer in the prostate of nude mice
Authors: Yazici S. , Kim S.J. , Busby J.E. , He J. , Thaker P. , Yokoi K. , Fan D. , Fidler I.J. 
Published: June 2005

AbstractBACKGROUNDAndrogen‐independent prostate cancer (PCa) may be susceptible to modulation of the tumor microenvironment. We determined whether a dual tyrosine kinase inhibitor (AEE788) of the epidermal growth factor receptor (EGF‐R) and vascular endothelial growth factor receptor (VEGF‐R) combined with chemotherapy can produce therapy of human PCa in nude mice.METHODSPC‐3MM2 human PCa cells were injected into the prostate of nude mice. Three days later, the mice were randomized into four groups: saline control, paclitaxel, AEE788, and AEE788 and paclitaxel. The mice were treated for 5 weeks and necropsied. Tumor incidence, weight, and incidence of lymph node metastasis were recorded. Tumor tissue was analyzed immunohistochemically.RESULTSTreatment of mice with AEE788 or AEE788 plus paclitaxel significantly decreased tumor incidence, total tumor weight, and incidence of lymph node metastasis. AEE788 treatment alone or in combination with paclitaxel inhibited the phosphorylation of EGF‐R and VEGF‐R on tumor cells and tumor‐associated endothelial cells. Therapeutic efficacy correlated with an increase in apoptosis of tumor cells and tumor‐associated endothelial cells.CONCLUSIONBlockade of EGF‐R and VEGF‐R signaling pathways coupled with chemotherapy suppressed the progressive growth and metastasis of human PCa cells growing orthotopically in nude mice. © 2005 Wiley‐Liss, Inc.
Assessment of intra‐individual variation in prostate‐specific antigen levels in a biennial randomized prostate cancer screening program in Sweden
Authors: Bruun Laila , Becker Charlotte , Hugosson Jonas , Lilja Hans , Christensson Anders 
Published: June 2005

AbstractBACKGROUNDThe degree of variability in prostate‐specific antigen (PSA) measurements is important for interpreting test results in screening programs, and particularly for interpreting the significance of changes between repeated tests. This study aimed to determine the long‐term intra‐individual variation for PSA in healthy men.METHODSA randomly selected cohort of men in a biennial prostate cancer screening program (ERSPC) conducted in Sweden from 1995–1996 to 2001–2002. We studied men who had total PSA (tPSA) levels < 2.0 ng/ml in 2001–2002. This included 791 men with tPSA ≤ 0.61 ng/ml (group A), 1,542 men with tPSA ≤ 0.99 ng/ml (group B), and 1,029 men with tPSA 1.00–1.99 ng/ml (group C). The intra‐individual variability of free PSA (fPSA) and tPSA was assessed by calculating coefficients of variation (CV) for each individual's PSA measurements from the first and second round of screening (1995–1996 and 1997–1998).RESULTSIntra‐individual CV (geometric means) for tPSA were 13.7%, 12.7%, and 11.5% in groups A, B, and C, respectively. Corresponding CVs for fPSA were significantly lower, ranging from 12.1% to 10.4%. The estimated biological variation of tPSA and fPSA in groups A to C were 12.5%, 11.4%, 10.0% and 9.7%, 7.8%, 7.5%, respectively.CONCLUSIONSIn healthy men with PSA levels less than 2 ng/ml, the natural long‐term variability for tPSA was less than 14%, and with 95% probability, a change in tPSA greater than 30% indicates a change beyond normal random variation. © 2005 Wiley‐Liss, Inc.
Lymphatic vessel density and lymph node metastasis in prostate cancer
Authors: Zeng Yiping , Opeskin Kenneth , Horvath Lisa G. , Sutherland Robert L. , Williams Elizabeth D. 
Published: June 2005

AbstractBACKGROUNDFew data are available examining the significance of prostatic lymphatic vessel density (LVD) to lymph node metastasis in patients with prostate cancer. The purpose of this study was to determine the distribution of lymphatic vessels in non‐carcinomatous prostate tissue, and investigate the relationship between LVD and lymph node status in prostate cancer.METHODSLVD, identified by D2‐40 immunostaining, was evaluated in non‐carcinomatous prostates (n = 7) and prostate cancer (n = 37). The staining pattern of D2‐40 was compared with that of another lymphatic vessel marker, vascular endothelial growth factor (VEGF) receptor‐3, and a blood vessel endothelial marker, CD34, in adjacent sections.RESULTSThe D2‐40 antigen, podoplanin, was expressed exclusively in lymphatic vessels within tumor and normal tissue in all specimens. There was no overlap between cell staining for D2‐40 and CD34. Peritumoral LVD and peritumoral lymphatic invasion were significantly associated with lymph node metastasis. VEGF receptor‐3 was expressed in a subset of D2‐40+ lymphatic vessels.CONCLUSIONSWe have demonstrated that peritumoral lymphatic vessels are likely to serve as major conduits for nodal metastasis in prostate cancer using D2‐40 to decorate lymphatic endothelium marker podoplanin. Lack of coexpression of podoplanin and VEGF receptor‐3 in some lymphatic vessels suggests the heterogeneity of lymphatic endothelial cells in prostate tissue. © 2005 Wiley‐Liss, Inc.
A role for surfactant protein D in innate immunity of the human prostate
Authors: Oberley Rebecca E. , Goss Kelli L. , Dahmoush Laila , Ault Kevin A. , Crouch Erika C. , Snyder Jeanne M. 
Published: June 2005

AbstractOBJECTIVESSurfactant protein D (SP‐D) is a member of the collectin family of proteins, which are involved in host defense mechanisms in the lung. In the present study, we found that SP‐D is produced in the human prostate where it may play a role in innate immunity.METHODS AND RESULTSUsing reverse‐transcriptase PCR and Western blot analysis, we demonstrate that SP‐D mRNA and protein are present in human prostate tissue. In situ hybridization and immunohistochemistry revealed that SP‐D mRNA and protein are localized in epithelial cells of prostate glands. Prostate glands that are surrounded by inflammatory cells produce increased amounts of SP‐D protein. We also show that SP‐D inhibits the infection of LNCaP and P69SV40T prostate epithelial cells by Chlamydia trachomatis in an in vitro infection assay. Furthermore, using truncated human SP‐D mutants, we demonstrate that SP‐D binds to Chlamydia trachomatis via its carboxy‐terminal lectin domains.ConclusionsOur in vitro studies suggest that SP‐D protects the prostate from infection by pathogens. SP‐D protein levels are increased at sites of inflammation in the prostate, suggesting SP‐D may also contribute more generally to inflammatory regulation in the prostate. © 2005 Wiley‐Liss, Inc.
Protamine: a unique and potent inhibitor of oligopeptidase B
Authors: Tsuji Akihiko , Yoshimoto Tadashi , Yuasa Keizo , Matsuda Yoshiko 
Published: June 2005

AbstractOligopeptidase B is a serine endopeptidase found in prokaryotes, unicellular eukaryotes and higher plants. The enzyme has been shown recently to play a central role in the pathogenesis of several parasitic diseases such as African trypanosomiasis, and to be a potential therapeutic target. This study reports that protamine, a basic peptide rich in arginine, is a potent inhibitor at the nanomolar level of oligopeptidase B from E. coli and wheat. Protamines 1B, 2C, 3A and TP17 displayed similar inhibitory activities and were capable of binding strongly to oligopeptidase B without proteolytic cleavage. The concentration of protamine needed for 50% inhibition (IC50) of oligopeptidase B was 104‐fold lower than the IC50 of trypsin. Oligopeptidase B was highly sensitive to inhibition by protamines even in the presence of serum (IC50, 1 µM). These data indicate that protamines might provide information useful for the design of more specific synthetic oligopeptidase B inhibitors. Copyright © 2005 European Peptide Society and John Wiley & Sons, Ltd.
Synthesis and secondary structure in membranes of the Bcl‐2 anti‐apoptotic domain BH4
Authors: Khemtémourian Lucie , Sani Marc‐Antoine , Bathany Katell , Gröbner Gerhard , Dufourc Erick J. 
Published: June 2005

AbstractSolid phase synthesis of BH4, the 26 amino‐acid domain (6RTGYDNREIVMKYIHYKLSQRGYEWD31) of the anti‐apoptotic Bcl‐2 protein has been accomplished using Fmoc chemistry. The use of peculiar cleavage conditions provided high yields after purification such that tens to hundreds of mg could be obtained. A 15N‐labelled version of the peptide could also be synthesized for NMR studies in membranes. The peptide purity was not lower than 98% as controlled by UV and MALDI‐TOF mass spectrometry. The secondary structure was determined in water, trifluoroethanol (TFE) and in lipid membrane using UV circular dichroism. The peptide shows dominant β‐sheeted structures in water that convert progressively into α‐helical features upon addition of TFE or membrane. The amphipathic character of the helix suggests that the peptide might have a structure akin to those of antimicrobial peptides upon interaction with membranes. Copyright © 2005 European Peptide Society and John Wiley & Sons, Ltd.
Effects of lanthanum doping on the dielectric, piezoelectric properties and defect mechanism of PZN–PZT ceramics prepared by hot pressing
Authors: Zeng X. , Ding A. L. , Deng G. C. , Liu T. , Zheng X. S. 
Published: June 2005

AbstractThe structure and electrical properties of Pb(Zn1/3Nb2/3)0.3(Zr0.55Ti0.45)0.7O3–xLa ceramics system by hot pressing with the composition near to the morphotropic phase boundary (MPB) were investigated as a function of La doping content. PZN–PZT specimens shifted from rhombohedral phase towards tetragonal phase with increasing La doping. Dielectric spectroscopy showed that La doping decreased dielectric permittivity maximum remarkably, and increased the degree of diffuse phase transition (DPT) with lower ferroelectric phase transition temperature. The growth of 1:1 chemically ordered domains through La doping was considered the cause of the dielectric dispersion. The high piezoelectric coefficient, d33 (716 pC/N), and electromechanical coupling factor, kp (0.62) were obtained in spite of existence of the pyrochlore phase. Oxygen vacancy conduction was the dominant mechanism. La doping reduced the concentration of oxygen vacancies, thus increased the electrical resistivity. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Evaluation of the diffusion length of gettered multicrystalline silicon using solar cells–cross‐sectional LBIC scan
Authors: Bouaïcha M. , Dimassi W. , Nouri H. , Bessaïs B. , Bennaceur R. 
Published: June 2005

AbstractThe effective bulk diffusion length (L) in multicrystalline silicon was evaluated using the light‐beam‐induced‐current (LBIC) technique using a geometrical configuration in which the front and back metallic contacts cover the entire front surfaces. The latter technique was performed on solar cells in cross section. We employed this particular configuration in order to evaluate the diffusion length independently of the recombination velocity at the front surface. For this purpose, we propose a new theoretical expression of the LBIC current. The diffusion length was found to be enhanced from 33 µm to 65 µm after gettering of undesired impurities from the bulk of the multicrystalline silicon. The gettering procedure used in this work is based on the formation of sacrificial porous silicon (PS) layers on both sides of the samples and heat treatments at different temperatures. This gettering method seems to concentrate some of the unwanted impurities close to the PS regions and to remove them by dissolving the PS layers. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Double‐peak‐structured photoluminescence mechanisms of porous silicon
Authors: Fang X. H. , Liao M. X. , Gu Y. , Wu X. L. 
Published: June 2005

AbstractWe have fabricated porous silicon films with photoluminescence (PL) peak wavelengths in the range of 560–710 nm. It was found that a double‐peak‐structured PL band frequently appears in such porous silicon films with central PL peak positions in the range of 590–660 nm. When their PL excitation spectra show a redshift with increasing monitored emission wavelength, these PL spectra generally have broader linewidths than those with PL peak positions beyond 590–660 nm. Based on the result of the self‐consistent effective‐mass calculation, we have attributed the two PL peaks in the double‐peak structure to band‐to‐band recombination in the quantum‐confined Si nanocrystals and optical transitions in the Si=O binding states at the surfaces of Si nanocrystals, respectively. This work improves the understanding of the double‐peak‐structured PL origin in porous silicon. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Band‐gap modification and tunable blue luminescence of wurtzite MgxZn1–xO thin films
Authors: Ogawa Yusuke , Fujihara Shinobu 
Published: June 2005

AbstractWe have demonstrated that sol–gel‐derived wurtzite‐type MgxZn1–xO films can exhibit reproducible blue emissions after heat treatments in a reducing atmosphere. Furthermore, the emission colors could be finely tuned by changing the Mg content x and band‐gap values. In contrast, the films showed orange emissions when they were heated in an oxidizing atmosphere. Our results then provided new insight into the mechanism of the visible emissions of ZnO. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Theoretical elastic properties of single‐walled carbon nanotubes
Authors: Alford J. T. , Landis B. A. , Mintmire J. W. 
Published: June 2005

AbstractCarbon fiber nanotubes are a relatively new material with amazing physical and electrical properties. We report the results of the first‐principles calculations for the elastic properties of several single‐walled carbon nanotubes (SWNT) with diameters of 4–17 Å. We show that the torsional and axial strain potential energy curves can be well described in terms of the experimental elastic constants of bulk graphite. © 2005 Wiley Periodicals, Inc. Int J Quantum Chem, 2005
Determination of glufosfamide in rat plasma by liquid chromatography/tandem mass spectrometry
Authors: Chen Xiaoyan , Sun Yuming , Cao Xueqin , Jin Fengdan , Zhong Dafang 
Published: June 2005

AbstractA sensitive and selective high‐performance analytical method based on liquid chromatography with tandem mass spectrometric detection (LC/MS/MS) was developed for the quantification of glufosfamide in rat plasma. Zidovudine was employed as internal standard. Glufosfamide was determined after methanol‐mediated plasma protein precipitation using LC/MS/MS with an electrospray ionization interface in negative ion mode. Two sets of standard curves were developed, from 0.005 to 1.0 µg/mL and from 1.0 to 50.0 µg/mL. The assay was accurate (% deviations from nominal concentrations < 5%), precise and reproducible (intra‐ and inter‐day coefficients of variation < 10%). Glufosfamide in rat plasma was stable over three freeze/thaw cycles, and at ambient temperatures, for at least 2 h. The validated method was successfully applied to the determination of glufosfamide plasma concentrations in rats for 24 h following an intravenous administration of 25 mg/kg. Copyright © 2005 John Wiley & Sons, Ltd.
The use of proteotypic peptide libraries for protein identification
Authors: Craig Robertson , Cortens John P. , Beavis Ronald C. 
Published: June 2005

AbstractThis paper describes an algorithm to apply proteotypic peptide sequence libraries to protein identifications performed using tandem mass spectrometry (MS/MS). Proteotypic peptides are those peptides in a protein sequence that are most likely to be confidently observed by current MS‐based proteomics methods. Libraries of proteotypic peptide sequences were compiled from the Global Proteome Machine Database for Homo sapiens and Saccharomyces cerevisiae model species proteomes. These libraries were used to scan through collections of tandem mass spectra to discover which proteins were represented by the data sets, followed by detailed analysis of the spectra with the full protein sequences corresponding to the discovered proteotypic peptides. This algorithm (Proteotypic Peptide Profiling, or P3) resulted in sequence‐to‐spectrum matches comparable to those obtained by conventional protein identification algorithms using only full protein sequences, with a 20‐fold reduction in the time required to perform the identification calculations. The proteotypic peptide libraries, the open source code for the implementation of the search algorithm and a website for using the software have been made freely available. Approximately 4% of the residues in the H. sapiens proteome were required in the proteotypic peptide library to successfully identify proteins. Copyright © 2005 John Wiley & Sons, Ltd.
The Aun cluster probe in secondary ion mass spectrometry: influence of the projectile size and energy on the desorption/ionization rate from biomolecular solids
Authors: Novikov Alexey , Caroff Martine , Della‐Negra Serge , Depauw Joël , Fallavier Mireille , Le Beyec Yvon , Pautrat Michèle , Schultz J. Albert , Tempez Agnès , Woods Amina S. 
Published: June 2005

AbstractA Au‐Si liquid metal ion source which produces Aun clusters over a large range of sizes was used to study the dependence of both the molecular ion desorption yield and the damage cross‐section on the size (n = 1 to 400) and on the kinetic energy (E = 10 to 500 keV) of the clusters used to bombard bioorganic surfaces. Three pure peptides with molecular masses between 750 and 1200 Da were used without matrix. [M+H]+ and [M+cation]+ ion emission yields were enhanced by as much as three orders of magnitude when bombarding with Au instead of monatomic Au+, yet very little damage was induced in the samples. A 100‐fold increase in the molecular ion yield was observed when the incident energy of Au was varied from 10 to 180 keV. Values of emission yields and damage cross‐sections are presented as a function of cluster size and energy. The possibility to adjust both cluster size and energy, depending on the application, makes the analysis of biomolecules by secondary ion mass spectrometry an extremely powerful and flexible technique, particularly when combined with orthogonal time‐of‐flight mass spectrometry that then allows fast measurements using small primary ion beam currents. Copyright © 2005 John Wiley & Sons, Ltd.
The high‐mass component (>m/z 10 000) of coal tar pitch by matrix‐assisted laser desorption/ionisation mass spectrometry and size‐exclusion chromatography
Authors: Millan Marcos , Morgan Trevor J. , Behrouzi Mahtab , Karaca Fatma , Galmes Carolina , Herod Alan A. , Kandiyoti Rafael 
Published: June 2005

AbstractThe size‐exclusion chromatography (SEC) of acetone‐soluble, pyridine‐soluble and pyridine‐insoluble fractions of a coal tar pitch indicates a bimodal distribution in each fraction. The proportion of high‐mass material excluded from the SEC column porosity increases with solvent polarity. The polymer calibration of SEC shows the mass range of the small molecules to be from ∼100 u to ∼6000 u, with the mass range of the large excluded molecules above 200 000 u and up to several million u. In contrast, matrix‐assisted laser desorption/ionisation mass spectrometry (MALDI‐MS) shows a similar low‐mass range of ion abundances (< m/z 6000), but with a smaller range of high‐mass ion abundances, from ∼m/z 10 000 to 100 000. The large molecules may have three‐dimensional structures to allow molecules of relatively low mass to behave as if they are of large size in SEC. Laser desorption mass spectrometry of the acetone‐ and pyridine‐soluble fractions produced molecular ions of polycyclic aromatics that can be related to the known compositions from gas chromatography (GC) mass spectrometry. The experimental conditions used to generate the bimodal distribution by MALDI‐MS involve reducing the ion signal intensities to avoid overload of the detector and enable detection of the high‐mass ions, by reducing the high‐mass detector voltage (i.e. sensitivity) and increasing the laser power. Copyright © 2005 John Wiley & Sons, Ltd.
Development and validation of a liquid chromatography/tandem mass spectrometry procedure for the quantification of adefovir in human plasma
Authors: Chen Xiaoyan , Liu Dan , Zhu Lin , Zhong Dafang 
Published: June 2005

AbstractTo investigate the pharmacokinetics of adefovir as an anti‐hepatitis B virus drug, a sensitive and specific liquid chromatography/tandem mass spectrometry method was developed and validated. After a simple protein precipitation using methanol, the post‐treatment samples were analyzed on a C18 column interfaced with a triple‐quadrupole tandem mass spectrometer using positive electrospray ionization. A structural analogue, PMPA, was used as the internal standard. The method was linear in the concentration range 0.25–100 ng/mL. The lower limit of quantification was 0.25 ng/mL. The intra‐ and inter‐day relative standard deviation over the entire concentration range was 5.7% or less. The accuracy determined at three concentrations (0.75, 10 and 80 ng/mL for adefovir) was within ±2.5% relative error. The method described here was successfully applied for the evaluation of pharmacokinetic profiles of adefovir after single oral administration doses of 5, 10 and 20 mg adefovir dipivoxil to ten healthy volunteers. Copyright © 2005 John Wiley & Sons, Ltd.