bluuebunny/crossref_metadata_2025_split huggingface dataset:
Ionizing radiation enhances the therapeutic potential of TRAIL in prostate cancer in vitro and in vivo: Intracellular mechanisms
Authors: Shankar Sharmila , Singh Thiyam Ramsing , Srivastava Rakesh K. 
Published: March 2004

AbstractBackgroundWe assessed the influence of sequential treatment of ionizing radiation followed by tumor necrosis factor (TNF)‐related apoptosis‐inducing ligand (TRAIL) on intracellular mechanisms of apoptosis of prostate tumor cells in vitro and in vivo.MethodsProstate normal and cancer cells were exposed to irradiation and TRAIL. Four‐ to 6‐week‐old athymic nude mice were injected s.c. with PC‐3 tumor cells. Tumor bearing mice were exposed to irradiation and TRAIL, either alone or in combination (TRAIL after 24 hr of irradiation), and tumor growth, apoptosis, and survival of mice were examined. Expressions of death receptors, Bcl‐2 family members, and caspase were measured by Western blotting, ELISA, and ribonuclease protection assay; tumor cellularity was assessed by H&E staining; inhibition of p53 was performed by RNA interference (RNAi) technology, and apoptosis was measured by annexin V/propidium iodide staining, and terminal deoxynucleotidyltransferase‐mediated nick end labeling assay.ResultsIrradiation significantly augmented TRAIL‐induced apoptosis in prostate cancer cells through upregulation of DR5, Bax, and Bak, and induction of caspase activation. Dominant negative FADD and p53 siRNA inhibited the synergistic interaction between irradiation and TRAIL. The pretreatment of cells with irradiation followed by TRAIL significantly enhanced more apoptosis than single agent alone or concurrent treatment. Furthermore, irradiation sensitized TRAIL‐resistant LNCaP cells to undergo apoptosis. The sequential treatment of xenografted mice with irradiation followed by TRAIL‐induced apoptosis through activation of caspase‐3, induction of Bax and Bak, and inhibition of Bcl‐2, and completely eradicated the established tumors with enhanced survival of nude mice.ConclusionThe sequential treatment with irradiation followed by TRAIL can be used as a viable option to enhance the therapeutic potential of TRAIL in prostate cancer. © 2004 Wiley‐Liss, Inc.
The effect of combined androgen ablation on the expression of alpha1A‐adrenergic receptor in the human prostate
Authors: Benaim Elie A. , Karam Jose A. , Soboorian M. Hossein , Roehrborn Claus G. , McConnell John D. , Lin Victor 
Published: March 2004

AbstractBackgroundThis study was designed to determine whether androgen ablation (AA) affects expression of alpha1A‐adrenergic receptors (AR) in the human prostate.MethodsConcentrations of alpha1A‐AR mRNA were determined in benign prostatic tissue from patients undergoing surgery after a 3‐month course of combined androgen ablation (CAD) therapy with leuprolide and flutamide, and a matched group of untreated patients with clinical BPH.ResultsMean concentration of alpha1A‐AR in the AA group was 0.53 ± 0.53 SD (range 0.026–1.55) attomol/mg. Control mean was 0.29 ± 0.22 SD (range 0.02–0.69; P = 0.3, two tailed t‐test). Tissue composition did not statistically differ between the two groups. Expression of alpha1A‐AR correlated with concentration of smooth muscle myosin heavy chain (SMMHC) (r = 0.84, P = 0.001). No significant differences were observed after adjusting for SMMHC content.ConclusionsA 3‐month course of CAD does not appear to have a significant effect on alpha1A‐AR mRNA expression in the human prostate. © 2004 Wiley‐Liss, Inc.
Can color doppler predict the uniformity of HIFU‐induced prostate tissue destruction?
Authors: Rouvière Olivier , Curiel Laura , Chapelon Jean‐Yves , Bouvier Raymonde , Ecochard René , Gelet Albert , Lyonnet Denis 
Published: March 2004

AbstractBackgroundTissue blood perfusion influences the results of some hyperthermia and thermotherapy procedures, but its role in the outcome of prostate cancer treatment by high‐intensity focused ultrasound (HIFU) has not been evaluated yet. We evaluated preoperative prostate color Doppler as a predictor of the efficacy of HIFU treatment.MethodsThirty‐five patients underwent pre‐ and post‐contrast color Doppler examination of the prostate before HIFU treatment. Specific software was used to calculate, on color Doppler images, the color pixel density (CPD), and the specific flow (SF, i.e., mean velocity × CPD) in different regions of interest. Post‐treatment sextant biopsies were obtained in 31 patients, 5.8 ± 2.8 months after HIFU treatment.ResultsNo significant correlation was found between the uniformity of HIFU‐induced tissue destruction observed on control biopsies and the pre‐treatment CPD/SF values in any region of interest, either before or after contrast injection. On the other hand, history of radiation therapy was significantly associated with homogeneous tissue destruction and history of hormone therapy was significantly associated with incomplete tissue destruction.ConclusionsColor Doppler cannot predict the uniformity of HIFU‐induced tissue destruction. History of radiation therapy was found to be a factor of favorable prognosis and history of hormone therapy was found to be a factor of poor prognosis in our population. © 2004 Wiley‐Liss, Inc.
Application of serum PSA to identify acute bacterial prostatitis in patients with fever of unknown origin or symptoms of acute pyelonephritis
Authors: Hara Noboru , Koike Hiroshi , Ogino Sojiro , Okuizumi Mina , Kawaguchi Mokoto 
Published: March 2004

AbstractBACKGROUNDExclusion of prostatitis in screening for prostate cancer (Cap) is a matter of concern in the prostate‐specific antigen (PSA) era. Yet, the identification of acute bacterial prostatitis (ABP), intentionally utilizing PSA in patients with pyrexia has been scarcely reported.METHODSIn total, 39 men, who presented at our department with a fever higher than 38.3°C, were randomly selected. We investigated the fraction of patients who had serum PSA levels higher than 4.0 ng/ml and categorized them according to an initial diagnosis of pyelonephritis, ABP, other urogenital infections, and fever of unknown origin (FUO).RESULTSSix of nine cases initially diagnosed as pyelonephritis, presented with elevated PSA levels between 9.5 and 75.1 ng/ml. All six cases of clinically diagnosed prostatitis had PSA elevated between 4.1 and 13.6 ng/ml. In 8 of 18 FUO cases, PSA was elevated between 5.1 and 77.0 ng/ml. PSA levels significantly correlated with age (P < 0.005). All 20 patients with elevated PSA received antibiotics, and serum PSA was significantly reduced in all cases (P < 0.001) together with the alleviation of fever and normalization of CRP.CONCLUSIONSPSA is a prompt and steady diagnostic tool for identifying ABP that might be missed or misdiagnosed. We recommend the measurement of PSA in cases not only with urologic infection but also puzzling pyrexia. © 2004 Wiley‐Liss, Inc.
A set of homology models of pore loop domain of six eukaryotic voltage‐gated potassium channels Kv1.1‐Kv1.6
Authors: Liu Hsuan‐Liang , Lin Jin‐Chung 
Published: March 2004

AbstractHomology models of the pore loop domain of six eukaryotic potassium channels, Kv1.1‐Kv1.6, were generated based on the crystallographic structure of KcsA. The results of amino acid sequence alignment indicate that these Kv channels are composed of two structurally and functionally independent domains: the N‐terminal ‘voltage sensor’ domain and the C‐terminal ‘pore loop’ domain. The homology models reveal that the pore loop domains of these Kv channels exhibit similar folds to those of KcsA. The structural features and specific packing of aromatic residues around the selectivity filter of these Kv channels are nearly identical to those of KcsA, whereas most of the structural variations occur in the turret as well as in the inner and outer helices. The distribution of polar and nonpolar side chains on the surfaces of the KcsA and Kv channels reveals that they exhibit a segregation of side chains common to most integral membrane proteins. As the hydrogen bond between Glu71 and Asp80 in KcsA plays an important role in stabilizing the channel, the substituted Val residue in the Kv family corresponding to Glu71 of KcsA stabilizes the channel by making hydrophobic contact with Tyr residue from the signature sequence of the selectivity filter. The homology models of these Kv channels provide particularly attractive subjects for further structure‐based studies. Proteins 2004. © 2004 Wiley‐Liss, Inc.
Potent Trypsin‐resistant hGH‐RH Analogues
Authors: Izdebski Jan , Witkowska Ewa , Kunce Danuta , Orłowska Alicja , Baranowska Bogusława , Wolińska‐Witort Ewa 
Published: March 2004

AbstractA series of analogues of hGH‐RH‐(1–29)‐NH2 designed to have metabolic stability has been synthesized. Standard Boc‐SPPS was employed, modified to permit the guanidinylation of amino side‐chains after chain assembly but before release from the resin. [Dat1, Har11, 12, 20, 21, 29, Ala15, Nle27, Asp28]‐, [Dat1, Har11, 20, 29, Orn12, Ala15, Nle27, Asp28]‐, and [Dat1, Gap11, 12, 21, 29, Ala15, Har20, Nle27, Asp28]‐hGH‐RH‐(1–29)‐NH2 were completely resistant to trypsin and about 50 times as potent as hGH‐RH‐(1–29)‐NH2 itself when injected subcutaneously in rats. These peptides are candidates for clinical application in the therapy of GH deficiency. Copyright © 2004 European Peptide Society and John Wiley & Sons, Ltd.
Theoretical study of the valence and K‐shell spectra of atmospherically relevant CO2
Authors: Olalla E. , Martín I. 
Published: March 2004

AbstractCalculations of intensities for E1 electronic transitions originating in the nonbonding orbitals of CO2 and ending in low‐Rydberg states, as well as the corresponding partial‐channel and total photoionization density of oscillator strength, have been performed with the molecular quantum defect orbital (MQDO) method. This article thus deals with both the nonbonding orbitals constituent of the outer valence shell and the atomic‐like K‐shell of CO2. A comparative analysis is made throughout the discrete and continuous spectral regions with the results of previously reported experimental and theoretical studies for this species. Good agreement is found in most cases. The MQDO approach in this and in previous applications to molecular Rydberg states has proved to yield results of quantitative quality as long as the involved states are not subject to strong perturbations. © 2004 Wiley Periodicals, Inc. Int J Quantum Chem, 2004
Vibronic intensities in diatomic molecules
Authors: Wood D. M. , Hochmann P. , Klasinc L. , McGlynn S. P. 
Published: March 2004

AbstractThe object of this work is to use vibronic intensity distributions to determine the bond lengths of diatomic molecules in excited electronic states without having to evaluate Franck–Condon (FC) integrals. More specifically, the intent is to derive simple linear or quadratic expressions that provide good correspondence of bond lengths obtained from experimental vibronic intensity ratios with the experimental bond lengths. To that end, we will construct power‐series expressions for the FC integral in the harmonic approximation in terms of a parameter that approaches zero as the vibrational frequencies of the two combining electronic states approach equality, show how these expressions may be truncated, and evaluate the range of bond length changes over which the various approximate equations are valid. The study covered 60 different electronic transitions in 40 different diatomics. Of these, 40 electronic transition data sets were considered good enough to merit analysis. It will be shown that both approximations perform well within the limit of their applicability. © 2004 Wiley Periodicals, Inc. Int J Quantum Chem, 2004
DFT study of bridge atom dependence of absorption and emitting wavelength of tridentate ligand chelates of aluminum
Authors: Kan Ying , Wu Guo‐Shi , Wang Li‐Duo , Qiu Yong 
Published: March 2004

AbstractThe energy band structures of two promising organic light‐emitting compounds, Al(Saph‐q) [(salicylidene‐o‐aminophenolato) (8‐quinolinoato) aluminum] and Al(azb‐q) [(o,o′‐dihydroxyazobenzene) (8‐quinolinoato)aluminum], were investigated using the approaches of density functional theory (DFT) at the B3LYP/ 6‐31G*//3‐21G* level, and the projected density of states (PDOS). The predicted maximum absorption wavelengths, 392 nm for Al(Saph‐q) and 496 nm for Al(azb‐q), were in good agreement with the experimentally determined, 420 nm and 504 nm. The different bridge atoms make considerable varieties of the frontier orbitals. The results were reasonably expounded via a detailed analysis of the electronic structure. © 2004 Wiley Periodicals, Inc. Int J Quantum Chem, 2004
Quantum mechanical studies of isomeric and conformeric structures of methyl‐chloro‐peroxide
Authors: Drougas Evangelos , Kosmas Agnie M. 
Published: March 2004

AbstractAb initio quantum mechanical studies are carried out for the isomeric structures and the torsional potential of methyl‐chloro‐peroxide. These species are important intermediates in the atmospheric reactions of methyl, methoxy, and methylperoxy radicals with chlorine dioxide, chlorine monoxide, and atomic chlorine, respectively. The calculations indicate that the peroxide form, CH3OOCl, with a skew geometry for C, O, O, and Cl atoms, is the lowest minimum energy structure followed by CH3OClO. The CH3ClO2 adduct is found to be much higher in energy. The calculated isomerization barriers are found to be relatively high to permit possible interconversion pathways. © 2004 Wiley Periodicals, Inc. Int J Quantum Chem, 2004
Hybrid QM/MM embedding approach for the treatment of localized surface states in ionic materials
Authors: Sokol Alexey A. , Bromley Stefan T. , French Samuel A. , Catlow C. Richard A. , Sherwood Paul 
Published: March 2004

AbstractWe present a hybrid quantum mechanical/molecular mechanical technique recently developed and implemented in the computational chemistry software environment, ChemShell, aimed at the study of reactions at the surfaces of ionic solids including reconstructed polar surfaces and interfaces. The method follows approaches commonly used for the treatment of point defects in the bulk of halide and oxide materials but also incorporates surface‐specific relaxation and electrostatic effects, which allows one to study adsorption of charged and strongly dipolar species as well as inherent structural and electronic surface defects. Applications of this embedding approach are illustrated with the investigation into electron trapping at the oxygen terminated polar surfaces of ZnO and related surface F centers. Processes discussed are of particular interest for heterogeneous catalysis as the species characterized prove to be active catalytic centers in methanol synthesis over ZnO. © 2004 Wiley Periodicals, Inc. Int J Quantum Chem, 2004
Low‐frequency intra‐ and intermolecular vibration modes of H‐bonded nucleobases in oligonucleotide double helixes and hydrated nucleotide duplex: Application of the PM3 method
Authors: Kabanov Artem V. , Komarov Vladislav M. , Yakushevich Ludmila V. , Teplukhin Alexander V. 
Published: March 2004

AbstractTo understand the physical mechanisms of the structural–dynamic organization of the DNA double helix, it is important to investigate the spectrum of vibration modes of Watson–Crick base pairs with different models of H‐bonding complexes. Using the PM3 technique, we calculate the energy of low‐frequency intra‐ and inter‐molecular vibration modes of isolated canonical nucleoside and nucleotide pairs and analyze the dependence on the elongation of oligonucleotide double helix. The vibration spectrum of hydrated duplex [d(ApA) · d(TpT)]−2 · 47H2O was also calculated to elucidate the role of water in formation of the DNA spectrum. The results are compared with the available experimental data and analytical estimations. © 2004 Wiley Periodicals, Inc. Int J Quantum Chem, 2004
Intact polar membrane lipids in prokaryotes and sediments deciphered by high‐performance liquid chromatography/electrospray ionization multistage mass spectrometry—new biomarkers for biogeochemistry and microbial ecology
Authors: Sturt Helen F. , Summons Roger E. , Smith Kristin , Elvert Marcus , Hinrichs Kai‐Uwe 
Published: March 2004

AbstractLipids from prokaryotic cell membranes can serve as sources of information on the biogeochemistry and microbial ecology of natural ecosystems. Traditionally, apolar derivatives of the intact polar membrane molecules, e.g., fatty acids, have been the major target of lipid‐based biogeochemical studies. However, when still intact, i.e., as glycerol esters and ethers with attached polar headgroups, membrane lipids are diagnostic for living prokaryotes, which makes them excellent biomarkers for the study of in situ microbial processes in geological systems such as sediments or soils. Intact polar lipids (IPLs) are attractive analytical targets because they are taxonomically more specific than their apolar derivatives and avoid exclusion of signals from prokaryotes that primarily build their membranes with ether‐bound lipids such as archaea and some bacteria. Here we report results from analyses of IPLs in pure cultures of biogeochemically relevant prokaryotes and marine sediments by high‐performance liquid chromatography/electrospray ionization ion‐trap mass spectrometry (HPLC/ESI‐IT‐MSn). This technique is suitable for screening of biomass and environmental samples for distinctive taxonomic structural features such as distribution of polar lipid headgroups, types of bonds between alkyl moiety and glycerol backbone, and the chain length and degree of unsaturation in the alkyl moieties. We present analytical protocols to decipher structural information from mass spectral data. The IPL contents in selected archaeal and bacterial species are diverse and qualify as molecular fingerprints. Applied to marine sediments, the approach provided detailed information on the dominant microbial groups. The IPLs from bacterial members of anaerobic methanotrophic communities in surface sediments at Hydrate Ridge resemble those found in Desulfosarcina variabilis. The presence of dietherglycerophospholipids, however, suggests the presence of other bacteria possibly affiliated with the deepest phylogenetic branches in the tree of life. Sediments from ∼90 m below the seafloor on the Peruvian continental margin are dominated by intact archaeal tetraethers with glycosidically bound hexoses as headgroups, consistent with a significant fraction of the community being archaea. Additional calditol‐based tetraethers imply that the sedimentary archaea are taxonomically linked to the crenarchaeal Sulfolobales. Copyright © 2004 John Wiley & Sons, Ltd.
Determination of impurities in pesticides and their degradation products formed during the wine‐making process by solid‐phase extraction and gas chromatography with detection by electron impact mass spectrometry. I. Vinclozoline, procymidone and fenitrothion
Authors: Jiménez Juan José , Bernal José Luis , del Nozal M. Jesús , Arias Elena , Bernal José 
Published: March 2004

AbstractThe presence of degradation products of vinclozoline, procymidone and fenitrothion, and of impurities from their commercial formulations, was studied in white and red wines elaborated from spiked must. After solid‐phase extraction the nature of the residues was established by gas chromatography with mass spectrometric detection. The structures of several degradation products and impurities are discussed and elucidated on the basis of their electron impact spectra. In elaborated wines the concentrations of the degradation products and impurities are lower than those of the original active ingredients. Aminofenitrothion and acetylamino‐formyl‐fenitrothion‐oxon are the main residues of fenitrothion in wine. For dicarboximides, an alcohol derivative of vinclozoline was found in addition to 3,5‐dichloroaniline. Copyright © 2004 John Wiley & Sons, Ltd.
Determination of cefuroxime in human serum or plasma by liquid chromatography with electrospray tandem mass spectrometry
Authors: Viberg Anders , Sandström Marie , Jansson Britt 
Published: March 2004

AbstractCefuroxime is a second‐generation cephalosporin used against different kinds of bacterial infections. To be able to optimize the dosing it is necessary to characterize the pharmacokinetics of cefuroxime which requires a selective and sensitive analytical method for cefuroxime in plasma or serum. A new rapid liquid chromatography/electrospray tandem mass spectrometry (LC/MS/MS) method, using cefotaxime as internal standard, was developed for analysis of cefuroxime in human serum. The work‐up procedure consisted of protein precipitation with acetonitrile/cefotaxime, and after centrifugation the supernatant was dissolved in mobile phase. The sample was injected on a SB‐CN column and the detection was performed using tandem mass spectrometry (MS/MS). The limit of quantification was determined to 0.025 μg/mL. The method was linear in the range 0.025–50 μg/mL with a coefficient of correlation >0.999. The limit of quantification and intra‐day variability were found to be the same for plasma samples, which indicates that the method is valid for serum as well as plasma samples. Copyright © 2004 John Wiley & Sons, Ltd.
Creation and comparison of MS/MS spectral libraries using quadrupole ion trap and triple‐quadrupole mass spectrometers
Authors: Josephs Jonathan L. , Sanders Mark 
Published: March 2004

AbstractSearchable libraries of MS/MS spectra, obtained using liquid chromatography/tandem mass spectrometry (LC/MS/MS) with data‐dependent scan mode switching on both quadrupole ion trap and triple‐quadrupole mass spectrometers in conjunction with electrospray ionization, are presented. The effects on library search scores of changing the parameters for producing collision‐induced dissociation (CID) on both instrument types are systematically evaluated. These observations serve as a basis for determining a universal set of conditions for building MS/MS libraries. A group of 19 closely related steroids was used. The ability to obtain library‐searchable spectra at low concentrations is demonstrated for the analysis of a sample of progesterone spiked with hydroxyprogesterone impurities at 0.1 and 0.01%. Copyright © 2004 John Wiley & Sons, Ltd.
A mixed matrix of 3‐hydroxypicolinic acid and pyrazinecarboxylic acid for matrix‐assisted laser desorption/ionization time‐of‐flight mass spectrometry of oligodeoxynucleotides
Authors: Zhou Lihua , Deng Huimin , Deng Qinying , Zhao Shankai 
Published: March 2004

AbstractA mixed matrix of 3‐hydroxypicolinic acid (3‐HPA) and pyrazinecarboxylic acid (PCA) was used for analysis of a variety of synthetic oligodeoxynucleotides ranging in length from 8–108‐mers by matrix‐assisted laser desorption/ionization time‐of‐flight mass spectrometry. The experimental results showed that DNA segments with masses in the range from 5000 to 10 500 Da can be analyzed with high resolution (isotopic peaks resolved) when 3‐HPA/PCA was prepared by mixing saturated 3‐HPA solution and saturated PCA solution (in 50% of a 0.5 mol/L solution of diammonium hydrogen citrate plus 50% acetonitrile) at the volume ratio of 4:1. Each component of a mixture of d(A)1–10 gave a well‐resolved peak. Moreover, when 3‐HPA/PCA was used to analyze two mixtures, one containing two 23‐mer DNA segments with a 9 Da difference (A and T) and the other with a 7 Da difference (AA and TG), the two 23‐mer ion peaks were well separated from each other and an isotopically resolved spectrum of each component was recorded. Under the identical experimental conditions, the sample‐to‐sample reproducibility, resolution, signal‐to‐noise ratio and the tolerance to metal salts, with 3‐HPA/PCA, were superior to those observed using 3‐HPA alone for analysis of DNA segments. Copyright © 2004 John Wiley & Sons, Ltd.