bluuebunny/crossref_metadata_2025_split huggingface dataset:
Identification of single eukaryotic cells with micro‐Raman spectroscopy
Authors: Rösch P. , Harz M. , Peschke K.‐D. , Ronneberger O. , Burkhardt H. , Popp J. 
Published: January 2006

AbstractFor a fast identification of eukaryotic cells such as yeast species without a cultivation step it should be possible to perform the investigation on only one single cell. Since yeasts as eukaryotes are heterogeneous and their Raman spectra are therefore dependent on the measuring position, one Raman spectra is not representative of the whole cell. In this contribution we demonstrate the application of average Raman spectra of a line scan over single yeast cells. These average spectra are used for classification with the help of a support vector machine. © 2006 Wiley Periodicals, Inc. Biopolymers 82:312–316, 2006This article was originally published online as an accepted preprint. The “Published Online” date corresponds to the preprint version. You can request a copy of the preprint by emailing the Biopolymers editorial office at biopolymers@wiley.com
The Interaction of Heteroaryl‐Acrylates and Alanines with Phenylalanine Ammonia‐Lyase from Parsley
Authors: Paizs Csaba , Katona Adrian , Rétey János 
Published: January 2006

AbstractAcrylic acids and alanines substituted with heteroaryl groups at the β‐position were synthesized and spectroscopically characterized (UV, HRMS, 1H NMR, and 13C NMR spectroscopy). The heteroaryl groups were furanyl, thiophenyl, benzofuranyl, and benzothiophenyl and contained the alanyl side chains either at the 2‐ or 3‐positions. While the former are good substrates for phenylalanine ammonia‐lyase (PAL), the latter compounds are inhibitors. Exceptions are thiophen‐3‐yl‐alanine, a moderate substrate and furan‐3‐yl‐alanine, which is inert. Possible reasons for these exceptions are discussed. Starting from racemic heteroaryl‐2‐alanines their D‐enantiomers were prepared by using a stereodestructive procedure. From the heteroaryl‐2‐acrylates, the L‐enantiomers of the heteroaryl‐2‐alanines were prepared at high ammonia concentration. These results can be best explained by a Friedel–Crafts‐type electrophilic attack at the aromatic part of the substrates as the initial step of the PAL reaction.
14N NMR and Two‐Dimensional Suspension 1H and 13C HRMAS NMR Spectroscopy of Ionic Liquids Immobilized on Silica
Authors: Brenna Stefano , Posset Tobias , Furrer Julien , Blümel Janet 
Published: January 2006

AbstractA variety of popular ionic liquids have been synthesized and characterized, including by optimized 14N NMR spectroscopy of the neat and dissolved ionic liquids. Ionic liquids incorporating Si(OEt)3 groups have been immobilized on silica in a well‐defined manner with the imidazolium moiety remaining intact. This has been proved by optimized one‐ and two‐dimensional 1H and 13C HRMAS NMR spectroscopy of the materials suspended in suitable solvents.
A Practical Ruthenium‐Catalyzed Cleavage of the Allyl Protecting Group in Amides, Lactams, Imides, and Congeners
Authors: Alcaide Benito , Almendros Pedro , Alonso Jose M. 
Published: January 2006

AbstractA convenient methodology for the deprotection of N‐allylic amide‐like moieties was developed. The first examples accounting for the ruthenium‐catalyzed deallylation of amides, lactams, imides, pyrazolidones, hydantoins, and oxazolidinones have been achieved by the sequential use of Grubbs carbene (isomerization step) and RuCl3 (oxidation step). A variety of substrates, including enantiopure multifunctional β‐ and γ‐lactams, can be employed.
Rho signaling in Entamoeba histolytica modulates actomyosin‐dependent activities stimulated during invasive behavior
Authors: Franco‐Barraza Janusz , Zamudio‐Meza Horacio , Franco Elizabeth , Domínguez‐Robles M. del Carmen , Villegas‐Sepúlveda Nicolás , Meza Isaura 
Published: January 2006

AbstractInteraction of Entamoeba histolytica trophozoites with target cells and substrates activates signaling pathways in the parasite. Phosphorylation cascades triggered by phospho‐inositide and adenyl‐cyclase‐dependent pathways modulate reorganization of the actin cytoskeleton to form structures that facilitate adhesion. In contrast, little is known about participation of Rho proteins and Rho signaling in actin rearrangements. We report here the in vivo expression of at least one Rho protein in trophozoites, whose activation induced actin reorganization and actin–myosin interaction. Antibodies to EhRhoA1 recombinant protein mainly localized Rho in the cytosol of nonactivated amoebae, but it was translocated to vesicular membranes and to some extent to the plasma membrane after treatment with lysophosphatidic acid (LPA), a specific agonist of Rho activation. Activated Rho was identified in LPA‐treated trophozoites. LPA induced striking polymerization of actin into distinct dynamic structures. Disorganization of these structures by inhibition of Rho effector, Rho‐kinase (ROCK), and by ML‐7, an inhibitor of myosin light chain kinase dependent phosphorylation of myosin light chain, suggested that the actin structures also contained myosin. LPA stimulated concanavalin‐A‐mediated formation of caps, chemotaxis, invasion of extracellular matrix substrates, and erythrophagocytosis, but not binding to fibronectin. ROCK inhibition impaired LPA‐stimulated functions and to some extent adhesion to fibronectin. Similar results were obtained with ML‐7. These data suggest the presence and operation of Rho‐signaling pathways in E. histolytica, that together with other, already described, signaling routes modulate actomyosin‐dependent motile processes, particularly stimulated during invasive behavior. Cell Motil. Cytoskeleton 2006. © 2006 Wiley‐Liss, Inc.
Long‐term cosmetic results and toxicity after accelerated partial‐breast irradiation
Authors: Chen Peter Y. , Vicini Frank A. , Benitez Pamela , Kestin Larry L. , Wallace Michelle , Mitchell Christina , Pettinga Jane , Martinez Alvaro A. 
Published: January 2006

AbstractBACKGROUNDThe objective of this study was to assess the cosmesis and toxicities in patients with early‐stage breast carcinoma who received treatment with accelerated partial breast irradiation (APBI) using interstitial brachytherapy.METHODSFrom April 1993 to December 2001, 199 patients with Stage I–II breast carcinoma received breast‐conserving therapy with APBI to the tumor bed alone through a low‐dose‐rate (LDR) or high‐dose‐rate (HDR) implant. A template guide was used. The LDR dose was 50 Gray (Gy) over 96 hours; the outpatient HDR implant delivered 32 Gy in 8‐Gy or 34 Gy in 10‐Gy twice‐daily fractions. Cosmesis (Harvard criteria) and toxicities (Radiation Therapy Oncology Group guidelines) were assessed at ≤ 6 months, 2 years, and 5 years.RESULTSThe median follow up was 6.4 years. Breast pain, edema, erythema, and hyperpigmentation all diminished over time. Breast fibrosis and hypopigmentation increased until the 2‐year mark and then stabilized. Fat necrosis and telangiectasia increased over time, with a fat necrosis rate of 11% at 5 years. Nearly all telangiectasias (34% at 5 yrs) were Grade 1 (< 2 mm). The remaining toxicities were Grade 1 at all follow‐up intervals. Infections (11%) occurred predominantly within the first month after treatment. Good‐to‐excellent cosmetic outcomes were noted in 95–99% of patients over time; cosmetic results stabilized at 2 years with excellent results increased out to 5 years.CONCLUSIONSAPBI with interstitial brachytherapy resulted in mild chronic toxicities, the majority of which diminished or reached a plateau over time. Long‐term cosmesis was good to excellent in 95–99% of patients and stabilized at 2 years. Cancer 2006. © 2006 American Cancer Society.
Ethanol‐induced alterations of the antioxidant defense system in rat kidney
Authors: Dinu Diana , Nechifor Marina T. , Movileanu Liviu 
Published: January 2006

AbstractWe report here the effects of chronic ethanol consumption on the antioxidant defense system in rat kidney. Thirty‐two male Wistar rats were randomly divided in two identical groups and were treated as follows: control group (water for fluid) and the ethanol‐fed group (2 g/kg body weight/24 h). The animals were sacrificed after 10 weeks, and respectively 30 weeks of ethanol consumption, and the renal tissue was isolated and analyzed. Results revealed that kidney alcohol dehydrogenase activities increased significantly after ethanol administration, but the electrophoretic pattern of alcohol dehydrogenase isoforms was unmodified. The SDS polyacrylamidegel electrophoretic study of kidney proteins has revealed the appearance of two new protein bands after long‐term ethanol consumption. The kidney reduced glutathione/oxidized glutathione ratio decreased, indicating an oxidative stress response due to ethanol ingestion. The malondialdehyde contents and xanthine oxidase activities were unchanged. The antioxidant enzymatic defense system showed a different response during the two periods of ethanol administration. After 10 weeks, catalase, glutathione peroxidase, glutathione reductase, and glucose‐6‐phosphate dehydrogenase were activated, while superoxide dismutase, glutathione transferase, and γ‐glutamyltranspeptidase levels were stationary. After 30 weeks, superoxide dismutase and glutathione peroxidase activities were unmodified, but catalase, glutathione transferase, γ‐glutamyltranspeptidase, glutathione reductase, and glucose‐6‐phosphate dehydrogenase activities were significantly increased. Remarkable changes have been registered after 30 weeks of ethanol administration for glutathione reductase and glucose‐6‐phosphate dehydrogenase activities, including an increase by 106 and 216' of control values, respectively. These results showed specific changes in rat kidney antioxidant system and glutathione status as a consequence of long‐term ethanol administration. © 2005 Wiley Periodicals, Inc. J Biochem Mol Toxicol 19:386‐395, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/jbt.20101
Tumor necrosis factor α‐mediated activation of c‐Jun NH2‐terminal kinase as a mechanism for fumonisin B1induced apoptosis in murine primary hepatocytes
Authors: Sharma Neelesh , Suzuki Hirofumi , He Quanren , Sharma Raghubir P. 
Published: January 2006

AbstractFumonisin B1is a mycotoxin produced byFusarium verticillioides, frequently associated with corn. It produces species‐specific and organ‐specific toxicity, including equine leukoencephalomalacia, porcine pulmonary edema, and hepatic or renal damage in most animal species. Fumonisin B1perturbs sphingolipid metabolism by inhibiting ceramide synthase. Our previous studies indicated that fumonisin B1caused localized activation of cytokines in liver produced by macrophages and other cell types that modulate fumonisin B1induced hepatic apoptosis in mice. The role of tumor necrosis factor α (TNFα) in fumonisin B1mediated hepatocyte apoptosis has been established; not much is known about the downstream events leading to apoptosis. In the current study, fumonisin B1induced apoptosis in primary culture of liver cells. In consistence with previous reports, fumonisin B1caused accumulation of sphingoid bases and led to increase in TNFα expression. Phosphorylated and total c‐Jun NH2‐terminal kinase (JNK) activities were increased after 24 h fumonisin B1treatment. JNK inhibitor (SP600125) and anti‐TNFα reduced the apoptosis induced by fumonisin B1. The role of JNK signaling in fumonisin B1induced apoptosis is downstream of TNFα production, as fumonisin B1‐mediated activation of JNK was reduced by the presence of anti‐TNFα in the medium, whereas the presence of JNK inhibitor did not change the fumonisin B1induced TNFα expression. Results of this study imply that generation of fumonisin B1induced TNFα results in modulation of mitogen activated protein kinases, particularly of JNK, and provides a possible mechanism for apoptosis in murine hepatocytes. © 2005 Wiley Periodicals, Inc. J Biochem Mol Toxicol 19:359‐367, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/jbt.20102
Malathion detoxification by human hepatic carboxylesterases and its inhibition by isomalathion and other pesticides
Authors: Buratti Franca M. , Testai Emanuela 
Published: January 2006

AbstractThe organophosphorothioate (OPT) pesticide malathion (MAL) in mammals is readily hydrolyzed by mammalian carboxylesterases (CE). The reaction competes with the CYP‐catalyzed formation of malaoxon (MOX), the toxic metabolite. Alterations or individual variations in CE activity may result in increased MOX formation, enhancing MAL toxicity. We have characterized the human hepatic CE activity in a panel of 18 human liver microsomes as well as the inhibitory effect of IsoMAL, a major impurity of MAL commercial formulations, parathion (PAR), chlorpyrifos (CPF), and chlorpyrifos‐oxon (CPFO). CE activity showed a low level of variation among individuals (4‐fold). The reaction consists of two different phases, differing in their affinity for MAL (Km1 = 0.25–0.69 μM; Km2 = 10.3–26.8 μM). The relatively low Km1 values confirmed that human CE efficiently detoxify MAL. IsoMAL was shown to be a potent noncompetitive inhibitor of MAL detoxification (Ki = 0.6 μM), with a higher inhibitory potency than CPF and PAR (Ki = 7.5 μM and 50 μM, respectively). These two latter compounds very likely act as mixed inhibitors. CPFO showed the highest inhibitory potency toward CE‐mediated detoxification, being characterized by a Ki = 22 nM. The present results provide useful information for a better understanding of possible interactions between different OPTs and for assessing the potential cumulative risk for exposure to OPT mixtures. © 2005 Wiley Periodicals, Inc. J Biochem Mol Toxicol 19:406–414, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/jbt.20106
Thermodynamic properties of Ag2OB2O3 glasses by a modified scale‐transformed energy space sampling Monte Carlo method
Authors: Nakamura Hideaki , Aniya Masaru 
Published: January 2006

AbstractThe density of states of Ag2OB2O3 glasses has been calculated by using a modified scale‐transformed energy space sampling algorithm. This algorithm combines the scale‐transformed energy space sampling algorithm and the Wang–Landau method. It is shown how the two algorithms can be combined to improve the efficiency of calculation. The thermodynamic properties, in particular the specific heat CV, of the above‐mentioned glass system is studied. At temperatures above 80 K, the value of specific heat Cv is close to 22 J/mol/K. At low temperatures, the deviations of Cv from a T3 behavior are discernible, that is, Cv/T3 exhibits a hump at T = 7 K, which is in good agreement with the reported experimental behavior. © 2006 Wiley Periodicals, Inc. J Comput Chem 27: 471–477, 2006
A new method to determine electrostatic potential around a macromolecule in solution from molecular wave functions
Authors: Yoshida Norio , Hirata Fumio 
Published: January 2006

AbstractThe three‐dimensional reference interaction site model integral equation theory (3D‐RISM) combined with the ab initio molecular orbital method (3D‐RISM‐SCF) is applied to a solvated macromolecular system. The solvation structure around a solute molecule is obtained from the 3D‐RISM integral equation under the electrostatic potential of the solute molecule, calculated by the ab initio molecular orbital theory. The electrostatic potential should be calculated on each grid point in the three‐dimensional real space. Therefore, the calculation of the electrostatic potential is the most time consuming part in this method. In this article, we propose a new procedure to save the computational cost for calculating the electrostatic potential and the solvated fock matrix. The strategy of this procedure is to evaluate the electrostatic potential and the solvated fock matrix in different ways, depending on the distance between solute and solvent. Inside the repulsive cores of solute atoms, it is possible to avoid the calculation of electrostatic potential and solvated Fock matrix by assuming the potential to be infinity. In the region sufficiently far from solute, they are evaluated classically by putting the effective point charge on each atom. In the intermediate region, the electrostatic potential is evaluated directly by integrating the molecular orbitals of the solute molecule. The electronic structure and the energy gradient of Methionine‐Enkephalin and solvation structure are estimated by using this procedure in aqueous solution, and are compared with the results from other procedures. The results are compared also with those from the continuum model. © 2006 Wiley Periodicals, Inc. J Comput Chem 27: 453–462, 2006
Comparative postnatal ontogeny of the skull in the australidelphian metatherian Dasyurus albopunctatus (Marsupialia: Dasyuromorpha: Dasyuridae)
Authors: Flores David A. , Giannini Norberto , Abdala Fernando 
Published: January 2006

AbstractWe describe the cranial ontogeny of an australidelphian marsupial, Dasyurus albopunctatus, using a combination of qualitative and quantitative approaches. We examined in detail qualitative morphological changes of just‐weaned individuals as compared to old adults; specifically, changes in 31 morphological structures (e.g., processes, foramina) and 38 changes in cranial joints. We also interpreted growth‐invariant structures in terms of their functional relevance. We performed a multivariate allometry analysis based on 14 cranial measurements taken from 31 specimens encompassing the entire postweaning period. Three variables (height of occipital plate, breadth of braincase, and height of mandible) showed the same allometric trends in D. albopunctatus and the three marsupial species studied previously in the same framework (Didelphis albiventris, Lutreolina crassicaudata, and Dromiciops gliroides). In addition, D. albopunctatus shared allometric trends in two variables (length of the upper postcanine row and length of the orbit) with the microbiotheriid D. gliroides. Most of the growth trends observed are interpreted as linked to the predominantly carnivorous dietary habit of adult D. albopunctatus. Because dasyuromorphians are most likely basal to the major Australasian radiation of marsupials, knowledge of ontogenetic changes in D. albopunctatus may shed light on the evolution of ontogeny in the highly diverse Australasian marsupial fauna. J. Morphol. © 2006 Wiley‐Liss, Inc.
An enhanced LC‐MS/MS method for microcystin‐LR in lake water
Authors: Li Chien‐Ming , Chu Ricky Yuan‐Yuan , Hsientang Hsieh Dennis Paul 
Published: January 2006

AbstractA LC‐MS/MS method with enhanced sensitivity and specificity was established for monitoring microcystin‐LR (MC‐LR) in drinking water supplies in southern Taiwan. The enhanced sensitivity was achieved by the selection of a doubly charged MC‐LR as the precursor ion to result in an multiple reaction monitoring (MRM) pair ions ofm/z498.6 → 135.0. Using this ion pair, a record low detection limit of 2 pg was achieved on column, found in the available literature. A sample preparation method involving C8 solid‐phase extraction gave satisfactory recoveries of the analyte. Nodularin, with structural similarity to MC‐LR, was used as an internal standard to minimize matrix effects of water samples collected from six different water reservoirs in southern Taiwan, where MC‐LR was detected at sub‐ppb levels in all the reservoirs. The best precision and accuracy of this method were found with samples prepared to contain MC‐LR at 0.1 and 1 µg l−1. This new method requires considerably smaller water sample volumes because of enhanced quantification sensitivity and hence reduces the time needed for analysis. It should serve as a useful example for method development for monitoring other members of the microcystin family in drinking water supplies. Copyright © 2006 John Wiley & Sons, Ltd.
The detection of red pigment‐concentrating hormone (RPCH) in crustacean eyestalk tissues using matrix‐assisted laser desorption/ionization–Fourier transform mass spectrometry: [M + Na]+ ion formation in dried droplet tissue preparations
Authors: Stemmler Elizabeth A. , Gardner Noah P. , Guiney Maureen E. , Bruns Emily A. , Dickinson Patsy S. 
Published: January 2006

AbstractRed pigment‐concentrating hormone (RPCH), an octapeptide found in crustaceans and insects with the sequence pGlu‐Leu‐Asn‐Phe‐Ser‐Pro‐Gly‐Trp‐NH2, is an N‐ and C‐terminally blocked uncharged peptide. These structural features are shared with many members of the larger adipokinetic hormone (AKH)/RPCH peptide family in insects. We have applied vacuum UV matrix‐assisted laser desorption/ionization (MALDI)‐Fourier transform ion cyclotron mass spectrometry (FTMS) to the direct analysis of crustacean sinus gland tissues, using 2,5‐dihydroxybenzoic acid (DHB) as the MALDI matrix, and have found that RPCH is detected in the cationized, [M + Na]+, form under conditions where other peptides in the direct tissue spectra are protonated without accompanying [M + Na]+ or [M + K]+ satellite peaks. The [M + H]+ ion for RPCH is not detected in tissue samples or for an RPCH standard, even when care is taken to eliminate metal ions. This behavior is not unprecedented; however, both direct tissue spectra and SORI‐CID spectra provide no clues to suggest that the ionizing agent is a metal cation. In this communication, we characterize the MALDI‐FTMS ionization and SORI‐CID mass spectra of the [M + Na]+ and [M + K]+ ions from RPCH, and report on the detection of this neuropeptide in sinus gland tissues from the lobster Homarus americanus and the kelp crab Pugettia producta. We describe two strategies, an on‐probe extraction procedure and a salt‐doping approach, that can be applied to previously analyzed MALDI tissue samples to enhance and unmask sodiated peptides that may otherwise be mistaken for novel neuropeptides. Copyright © 2006 John Wiley & Sons, Ltd.
Automated software‐guided identification of new buspirone metabolites using capillary LC coupled to ion trap and TOF mass spectrometry
Authors: Fandiño Anabel S. , Nägele Edgar , Perkins Patrick D. 
Published: January 2006

AbstractThe identification and structure elucidation of drug metabolites is one of the main objectives in in vitro ADME studies. Typical modern methodologies involve incubation of the drug with subcellular fractions to simulate metabolism followed by LC‐MS/MS or LC‐MSn analysis and chemometric approaches for the extraction of the metabolites. The objective of this work was the software‐guided identification and structure elucidation of major and minor buspirone metabolites using capillary LC as a separation technique and ion trap MSn as well as electrospray ionization orthogonal acceleration time‐of‐flight (ESI oaTOF) mass spectrometry as detection techniques.Buspirone mainly underwent hydroxylation, dihydroxylation and N‐oxidation in S9 fractions in the presence of phase I co‐factors and the corresponding glucuronides were detected in the presence of phase II co‐factors. The use of automated ion trap MS/MS data‐dependent acquisition combined with a chemometric tool allowed the detection of five small chromatographic peaks of unexpected metabolites that co‐eluted with the larger chromatographic peaks of expected metabolites. Using automatic assignment of ion trap MS/MS fragments as well as accurate mass measurements from an ESI oaTOF mass spectrometer, possible structures were postulated for these metabolites that were previously not reported in the literature. Copyright © 2006 John Wiley & Sons, Ltd.