bluuebunny/crossref_metadata_2025_split huggingface dataset:
Simultaneous characterization of progenitor cell compartments in adult human liver
Authors: Porretti Laura , Cattaneo Alessandra , Colombo Federico , Lopa Raffaella , Rossi Giorgio , Mazzaferro Vincenzo , Battiston Carlo , Svegliati‐Baroni Gianluca , Bertolini Francesco , Rebulla Paolo , Prati Daniele 
Published: December 2009

AbstractThe human liver is a complex tissue consisting of epithelial, endothelial, hematopoietic, and mesenchymal elements that probably derive from multiple lineage‐committed progenitors, but no comprehensive study aimed at identifying and characterizing intrahepatic precursors has yet been published. Cell suspensions for this study were obtained by enzymatic digestion of liver specimens taken from 20 patients with chronic liver disease and 13 multiorgan donors. Stem and progenitor cells were first isolated, amplified, and characterized ex vivo according to previously validated methods, and then optimized flow cytometry was used to assess their relative frequencies and characterize their immunophenotypes in the clinical specimens. Stem and progenitor cells committed to hematopoietic, endothelial, epithelial, and mesenchymal lineages were clearly identifiable in livers from both healthy and diseased subjects. Within the mononuclear liver cell compartment, epithelial progenitors [epithelial cell adhesion molecule (EpCAM)+/CD49f+/CD29+/CD45−] accounted for 2.7–3.5% whereas hematopoietic (CD34+/CD45+), endothelial [vascular endothelial growth factor‐2 (KDR)+/CD146+/CD45−], and mesenchymal [CD73+/CD105+/CD90 (Thy‐1)+/CD45 −] stem cells and progenitors accounted for smaller fractions (0.02–0.6%). The patients' livers had higher percentages of hematopoietic and endothelial precursors than those of the donors. In conclusion, we identified and characterized precursors committed to four different lineages in adult human liver. We also optimized a flow cytometry approach that will be useful in exploring the contribution of these cells to the pathogenesis of liver disease. © 2009 International Society for Advancement of Cytometry
Steroid metabolism in chimeric mice with humanized liver
Authors: Lootens Leen , Van Eenoo Peter , Meuleman Philip , Pozo Oscar J. , Van Renterghem Pieter , Leroux‐Roels Geert , Delbeke Frans T. 
Published: December 2009

AbstractAnabolic androgenic steroids are considered to be doping agents and are prohibited in sports. Their metabolism needs to be elucidated to allow for urinary detection by gas chromatography‐mass spectrometry (GC‐MS) or liquid chromatography‐tandem mass spectrometry (LC‐MS/MS). Steroid metabolism was assessed using uPA+/+ SCID mice with humanized livers (chimeric mice). This study presents the results of 19‐norandrost‐4‐ene‐3,17‐dione (19‐norAD) administration to these in vivo mice. As in humans, 19‐norandrosterone and 19‐noretiocholanolone are the major detectable metabolites of 19‐norAD in the urine of chimeric mice.A summary is given of the metabolic pathways found in chimeric mice after administration of three model steroid compounds (methandienone, androst‐4‐ene‐3,17‐dione and 19‐norandrost‐4‐ene‐3,17‐dione). From these studies we can conclude that all major metabolic pathways for anabolic steroids in humans are present in the chimeric mouse. It is hoped that, in future, this promising chimeric mouse model might assist the discovery of new and possible longer detectable metabolites of (designer) steroids. Copyright © 2009 John Wiley & Sons, Ltd.
Spectrophotometric determination of peptic ulcer sulfur‐containing drugs in bulk form and in tablets
Authors: Mohamed Gehad G. , Nour El‐Dien F. A. , Khalil Shaban M. , El‐Tantawy Aliaa S. M. 
Published: December 2009

AbstractTwo spectrophotometric procedures are suggested for the determination of three irreversible proton pump inhibitors, rabeprazole (RAB), omeprazole (OMP) and pantoprazole (PAN) in pure form and in different pharmaceutical formulations. The first method is based on the oxidation of RAB and PAN with potassium iodate in an acidic medium followed by extracting the liberated iodine with cyclohexane and measurement at λ = 520 nm. Beer's law is valid in the concentration ranges from 10–400 and 5–400 µg ml−1 for RAB and PAN, respectively. The apparent molar absorptivities of the resulting coloured product were found to be 1.34 × 103 and 1.64 × 103 l.mol−1. cm−1 for RAB and PAN, respectively. The second method is based on the interaction of the basic drugs, OMP, RAB and PAN, in 1,2‐dichloroethane with bromophenol blue (BPB), bromocresol green (BCG) and bromocresol purple (BCP) in the same solvent to produce stable coloured ion pairs with maximum absorbance at 385–405 nm. Regression analysis of Beer's plots showed good correlation in the concentration ranges 10–60, 10–60 and 5–40 µg ml−1 for OMP, 10–150, 10–150 and 10–60 µg ml−1 for RAB and 10–250, 10–150 and 10–100 µg ml−1 for PAN with BPB, BCG and BCP reagents, respectively. The limits of detection are 0.46–7.69 µg ml−1 and limits of quantitation range between 1.52–8.53 µg ml−1. The optimum assay conditions were investigated and the recovery of the drugs from their dosage forms ranged from 99.33% to 100.5%. Intraday relative standard deviations (RSD) were 0.029–1.397% and the correlation coefficients ranged from 0.9992 to 1. The two methods can be applied successfully for the determination of these drugs in tablets. The results of analysis were validated statistically through recovery studies. Copyright © 2009 John Wiley & Sons, Ltd.
Ethene Polymerization Behavior of MAO‐Activated Dichloridotitanium Complexes Bearing Bi‐ and Tetradentate Salicylaldimine Derivatives
Authors: Pärssinen Antti , Luhtanen Tommi , Pakkanen Tapani , Leskelä Markku , Repo Timo 
Published: December 2009

AbstractNew chiral bridged tetradentate (N2O2)TiIVCl2‐type complexes bearing dimethylbiphenyl (1‐Ti–3‐Ti) and previously published binaphthyl‐bridged (4‐Ti) complex were synthesized with high yields. This was achieved by treating the corresponding Schiff‐base ligand (H2L) precursors with Ti(NMe2)4, followed by conversion of these diamido complexes to LTiCl2 derivatives by the addition of excess of Me3SiCl. A series of unbridged titanium complexes 5‐Ti–8‐Ti with similar substituents at the phenoxy group were studied and their polymerization properties, after methylaluminoxane (MAO) activation, compared with the above bridged complexes. It was found that the catalysts bearing chiral tetradentate biaryl‐bridged salicylaldimine ligands produce multimodal polyethylene (PE) with low activity [below 10 kgPE/(molTi h bar)] while their unbridged analogues provide activities that are 10–1000 times greater under similar reaction conditions. The reasons for this dramatic difference in polymerization activities are discussed based on the stabilities of the different cationic species configurations.
Enantiopure 2‐(Trifluoromethyl)‐1,2,3,4‐tetrahydronaphthalene‐1,2‐diols from a Tartaric Acid Derived Scaffold
Authors: Massicot Fabien , Nonnenmacher Jean , Grellepois Fabienne , Portella Charles 
Published: December 2009

AbstractThe synthesis of the four stereoisomers of 2‐(trifluoromethyl)tetrahydronaphthalene‐1,2‐diols and/or their 2‐O‐allyl derivatives is reported. Nucleophilic trifluoromethylation of a tartaric acid derived keto amide, and a one‐pot hydrolysis/oxidative cleavage/intramolecular Friedel–Crafts transformation are the main features of this synthesis.
Why mood affects help giving, but not moral courage: Comparing two types of prosocial behaviour
Authors: Niesta Kayser Daniela , Greitemeyer Tobias , Fischer Peter , Frey Dieter 
Published: December 2009

AbstractA long tradition in the help giving literature assumes that mood states determine the level of prosocial behaviour shown by individuals. Most research in this area has been conducted in the context of low cost prosocial behaviour, whereas research has been neglected in which participants were confronted with situations involving potential severe and dangerous negative consequences (i.e., high cost situations) with the help‐giver risking his moral integrity and social disapproval (i.e., moral courage). To address this gap in the literature, the present studies investigate differential effects of positive and negative compared with neutral mood states on help giving versus moral courage. Study 1 shows that in situations requiring low cost helping, participants were more likely to help in positive and negative moods than those in a neutral mood, whereas in situations requiring moral courage (high cost), participants were comparably likely to help in each of the three mood conditions. In Study 2, we find that salience of moral norms mediates the interaction between type of prosocial behaviour and mood. Finally, Study 3 investigates whether the apparent discrepancy between help giving and moral courage as established by the differential impact of mood states can be determined still differently. It reveals that justice sensibility, civil disobedience, resistance to group pressure, moral mandates, and anger lead to moral courage, but not to help giving. Differences between these two types of prosocial behaviour are discussed. Copyright © 2009 John Wiley & Sons, Ltd.
A systematic study in CIEF: Defining and optimizing experimental parameters critical to method reproducibility and robustness
Authors: Mack Scott , Cruzado‐Park Ingrid , Chapman Jeff , Ratnayake Chitra , Vigh Gyula 
Published: December 2009

AbstractA systematic study of two‐step CIEF analysis was completed to identify key components that could be optimized to enhance the performance of mAb analysis by CIEF. Resolution between mAb isoforms was increased by selecting a narrow detector aperture, utilizing chemical rather than pressure mobilization, and improving protein solubility by incorporating urea into the carrier ampholyte (CA) solutions. Loss of the extreme pI CAs and sample components by the bidirectional ITP inherent to IEF was avoided by setting the concentration of the phosphoric acid anolyte to 200 mM and sodium hydroxide catholyte to 300 mM and by adding sufficient amounts of an acidic (pI<3) and basic (10<pI) sacrificial ampholyte to the CIEF sample solution. Optimization of the concentrations of the sacrificial ampholytes, iminodiacetic acid and arginine to 1.7 and 40 mM, respectively, yielded a stable focused CA train that spanned the 4<pH<10 range without sacrificing either mAb isoform resolution or sample throughput. Intermediate precision studies performed on the CIEF method with three basic mAbs yielded 0.04 to 0.09% CVs for the estimated pI values and 0.6−3% CVs for isoform group percent composition, indicating that the two‐step CIEF method developed meets the rigorous demands of therapeutic mAb analysis.
A novel methodology for the analysis of membrane and cytosolic sub‐proteomes of erythrocytes by 2‐DE
Authors: Alvarez‐Llamas Gloria , de la Cuesta Fernando , Barderas Maria G. , Darde Veronica M. , Zubiri Irene , Caramelo Carlos , Vivanco Fernando 
Published: December 2009

AbstractWith the aim of studying a wide cohort of erythrocyte samples in a clinical setting, we propose here a novel approach that allows the analysis of both human cytosolic and membrane sub‐proteomes. Despite their simple structure, the high content of hemoglobin present in the red blood cells (RBCs) makes their proteome analysis enormously difficult. We investigate here different strategies for isolation of the membrane and cytosolic fractions from erythrocytes and their influence on proteome profiling by 2‐DE, paying particular attention to hemoglobin removal. A simple, quick and satisfactory approach for hemoglobin depletion based on HemogloBind™ reagent was satisfactorily applied to erythrocyte cells, allowing the analysis of the cytosolic sub‐proteome by 2‐DE without major interference. For membrane proteome, a novel combined strategy based on hypotonic lysis isolation and further purification on minicolumns is described here, allowing detection of high molecular weight proteins (i.e. spectrin, ankyrin) and well‐resolved 2‐DE patterns. An aliquot of the membrane fraction was also in solution digested and analyzed by nano‐LC coupled to an LTQ‐Orbitrap mass spectrometer. A total of 188 unique proteins were identified by this approach. This study sets the basis for future clinical studies where the erythrocyte cell may be implicated.
Online CIEF‐ESI‐MS in glycerol–water media with a view to hydrophobic protein applications
Authors: Mokaddem Meriem , Gareil Pierre , Varenne Anne 
Published: December 2009

AbstractA new online coupling of CIEF with ESI‐MS has been developed in glycerol–water media. This improved protocol provides: (i) the electric continuity during the whole analysis by a discontinuous filling of the capillary with 60:40 (cm/cm) catholyte/proteins–ampholyte mixture; (ii) the use of an anticonvective medium, i.e. 30:70 glycerol/water, v/v, compatible with MS detection and as an aid to hydrophobic protein solubilization and (iii) the use of unmodified bare fused‐silica capillaries, as the glycerol/water medium strongly reduces EOF. Focusing was performed in positive polarity and cathodic mobilization was achieved by both voltage and pressure application. The setup was optimized with respect to analysis time, sensitivity and precision on pI determination. The optimized anolyte and catholyte were composed of 50 mM formic acid/1 mM glutamic acid (pH 2.35) and 100 mM NH3/1 mM lysine (pH 10.6), respectively. The effects of ampholyte concentration, focusing time and ESI parameters were presented for model proteins and discussed. This new integrated protocol should be an easy and effective additional tool in the field of proteome analysis, providing a means for the characterization of a large number of hydrophilic and hydrophobic proteins.
Microchip isoelectric focusing with monolithic immobilized pH gradient materials for proteins separation
Authors: Liang Yu , Cong Yongzheng , Liang Zhen , Zhang Lihua , Zhang Yukui 
Published: December 2009

AbstractMonolithic immobilized pH gradient (M‐IPG) materials were prepared in microchannles by photoinitiated polymerization of acrylamide, glycidylmethacrylate and Bis, followed by the attachment of focused Ampholine onto the surface of porous monoliths via epoxide groups. With M‐IPG materials as matrix, FITC‐labeled ribonuclease B, myoglobin and α‐casein were well separated by microchip isoelectric focusing (μCIEF) without carrier amphocytes (CAs) added in the buffer. Both chemical and pressure mobilization were applied to drive focused zones for LIF detection. Our experimental results showed that pressure mobilization was preferable with neglectable band broadening, and good peak shape and high detection sensitivity were obtained. All these results demonstrate that μCIEF with M‐IPG materials is not only an efficient mode for protein enrichment and separation but also attractive to couple with other CE modes to achieve multi‐dimensional separation or MS for further identification, without the interference of mobile CAs.
Study of metallothionein oxidation by using of chip CE
Authors: Krizkova Sona , Adam Vojtech , Kizek Rene 
Published: December 2009

AbstractMetallothionein (MT) is a low‐molecular mass protein playing an essential role in homeostasis of heavy metals ions. We used a chip‐based CE for quantitative study of MT oxidation. After oxidation of MT by H2O2 we observed marked decrease in peaks heights and shift of peaks positions to higher molecular mass, which corresponded with the time of the oxidation. Moreover, we observed that the proportion of high‐molecular forms of MT was markedly increased. The oxidative changes were successfully reversed by using of reducing agent prior to electrophoresis. Our method can reveal the stability MT aggregates, of which biological role still remains unclear.
Quantitative protein expression profiling of 14‐3‐3 isoforms in human renal carcinoma shows 14‐3‐3 epsilon is involved in limitedly increasing renal cell proliferation
Authors: Liang Shufang , Xu Yuhuan , Shen Guobo , Liu Qingping , Zhao Xinyu , Xu Zhizhong , Xie Xi , Gong Fengming , Li Ronghui , Wei Yuquan 
Published: December 2009

Abstract14‐3‐3 proteins regulate many cellular processes that are implicated in cancer development, and the seven 14‐3‐3 isoforms have different expression level and isoform‐specific roles in different tumors. However, the biological functions of 14‐3‐3 proteins and their correlations with renal carcinoma have not been investigated so far. In our study, the expression profiles and functional characterization of 14‐3‐3 proteins were discovered by a sensitive stable isotope labeling with amino acids in cell culture based quantitative proteomics analysis in human renal carcinoma tissues. We found that 14‐3‐3ε was up‐regulated with 1.44‐fold changes in renal cancerous tissues compared with that in counterpart kidney tissues, and 14‐3‐3σ was almost not detected in both tissues due to its DNA highly methylated in our previous reports. The other five isoforms almost have similar expression level in two states of renal tissues. The following RT‐PCR, Western blot and immunohistochemistry analysis for specific 14‐3‐3 isoform expression were all consistent with the quantitative proteomic data. Furthermore, the overexpression of 14‐3‐3ε in vitro can limitedly prompt the abnormal growth of renal tumor cells.
Robust features for 2‐DE gel image registration
Authors: Möller Birgit , Posch Stefan 
Published: December 2009

AbstractProteomics is a rapidly growing field of modern biology. Since quantitative data of proteins involved in dynamic processes of living organisms are essential for understanding the basics of life, techniques like 2‐DE and related procedures for automatic data interpretation are at the heart of this research field. They are strongly required to enable analysis and interpretation of the emerging amount of available data. Analyzing and interpreting gel image data usually requires the comparison of gels from different experiments and, thus, a prior registration of gels. This can be accomplished using featureless, feature‐based or hybrid registration approaches combining both techniques. Recently, the latter ones have shown high performance, and it is undoubtful that in general robust and reliable features are an essential ingredient and valuable source of information for high‐quality image registration. In this paper we provide a thorough overview and elaborate analysis of the capabilities of available feature detectors for gel image registration. Particularly, a detailed and extensive comparative study is presented where common spot‐specific detectors are included as well as image‐content independent detectors that were not applied to the task of gel image registration until now. The study incorporates tests on several thousand synthetically deformed images from different experimental conditions. As a result it provides valuable quantitative data allowing for direct objective comparisons of various detectors, and is well suited to guide the design of new registration algorithms.
Analysis of integral membrane proteins by heat gel‐embedment combined with improved in‐gel digestions
Authors: Zhou Jian , Huang Sha , Bi Deng , Zhang Hai , Li Jianglin , Lin Yong , Chen Ping , Wang Xianchun , Liang Songping 
Published: December 2009

AbstractAnalysis of integral membrane proteins (IMPs) presents a special challenge because of their hydrophobic nature and low abundance. Here, a new method was developed, which involved heat gel‐embedment and improved in‐gel digestion of the proteins. Membrane protein lysate containing detergents was mixed with acrylamide solution and the proteins were embedded when the gel polymerized. For comparison, the protein embedment was made at different temperatures (25, 35 or 45°C), and the in‐gel digestions were performed in the presence of 0.1% RapiGest reagent (ALS), 0.1% sodium deoxycholate and 10% ACN, respectively. The resultant peptides were extracted and analyzed by capillary liquid chromatography coupled with tandem mass spectrometry. Compared with that at 25°C, gel‐embedment at 45°C improved the protein embedment and thus protein identification, with the identified IMPs increased by 27%. 0.1% sodium deoxycholate was more efficient than 0.1% ALS and 10% ACN in terms of improving the digestion and tryptic digest recovery of the gel‐embedded proteins particularly the hydrophobic IMPs. Out of the 326 IMPs identified by heat gel‐embedment combined with improved in‐gel digestion strategies, 149 (46%) proteins had at least two mapped transmembrane domains. These results indicate that our newly developed protocol could facilitate the high throughput analysis of integral membrane proteome.
CE‐MALDI interface based on inkjet technology
Authors: Vannatta Michael W. , Whitmore Colin D. , Dovichi Norman J. 
Published: December 2009

AbstractAn ink jet printer valve and a nozzle were used to deliver matrix and sample from an electrophoresis capillary onto a MALDI plate. The system was evaluated by the separation of a set of standard peptides. That separation generated up to 40 000 theoretical plates in less than 3 min. Detection limits were 500 amol for an ABI TOF‐TOF instrument and 2 fmol for an ABI Q‐TOF instrument. Over 70% coverage was obtained for the tryptic digest of α‐lactalbumin in less than 2.5 min.
Optimisation of protein extraction and 2‐DE for metaproteomics of microbial communities from anaerobic wastewater treatment biofilms
Authors: Abram Florence , Gunnigle Eoin , O'Flaherty Vincent 
Published: December 2009

AbstractThe feasibility of metaproteomic analysis of the microbial communities underpinning anaerobic wastewater treatment relies on efficient protein extraction and separation techniques. The microorganisms involved in anaerobic digestion (AD) of wastewater typically aggregate to form tightly organised, spherical granules, from which protein extraction is challenging. Here, we compare two methods of protein extraction, one using a French press previously used successfully to analyse the proteome of an activated sludge [Wilmes, P., Bond, P. L., Environ. Microbiol. 2004, 6, 911–920.] and one using sonication developed in the context of pure culture [Abram, F., Wan‐Lin, S., Wiedmann, M., Boor, K. J., Coote, P., Botting, C., Karatzas, K. A. G., O'Byrne, C. P., Appl. Environ. Microbiol. 2008, 74, 594–604.]. We used 2‐DE to carry out this comparison. The protein extraction using the sonication method resulted in a significant increase in the number of protein spots and higher quality 2‐D gels.