bluuebunny/crossref_metadata_2025 huggingface dataset:
Molecular dynamics (MD) simulations of VIP and PACAP27
Authors: Corcho Francesc J. , Mokoena Paul , Bisetty Krishna , Perez Juan J.
Published: January 2009

Vasoactive intestinal peptide (VIP) and pituitary adenylate cyclase‐activating polypeptide‐27 (PACAP27) are members of the secretin‐glucagon family containing 28 and 27 residues, respectively. NMR spectroscopy studies suggest that the N‐terminus exhibit consecutive β‐turns whereas the central and C‐terminal parts of the VIP molecule have been characterized as being two α‐helices. In contrast, similar studies carried out on PACAP suggest that the shortest active peptide segment PACAP27 in the presence of trifluoroethanol (TFE) exhibits a disordered N‐terminal domain followed by a α‐helix expanding residues 9–26 with a discontinuity between residues 20 and 21. In the present study, a series of MD trajectories of VIP and PACAP27 were carried out using two different implicit models of the solvent: the Generalized Born that use an effective Born radii described by Onufriev, Bashford, and Case (GBOBC) and the Hawkins, Cramer, and Truhlar approximation (GBHCT) and two different force fields: AMBER ff99 and a modified version of the latter described by Sorin and Pande (Biophys J 2005, 88, 2472‐2493), ff99SP. Comparison of the structures obtained from the MD trajectories and those derived from the NMR studies in the literature indicates that the GBOBCmethod is more efficient in the exploration of the conformational space and presents a higher agreement with the experimental structure of VIP and PACAP27 in TFE. © 2009 Wiley Periodicals, Inc. Biopolymers 91: 391–400, 2009.

This 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
Maltreated children's understanding of and emotional reactions to dependency court involvement
Authors: Quas Jodi A. , Wallin Allison R. , Horwitz Briana , Davis Elizabeth , Lyon Thomas D.
Published: January 2009

Little is known about the extent to which maltreated children understand what is happening during their participation in court proceedings, despite large numbers of children coming into contact with the legal system as victims of maltreatment. In the present study, maltreated 4‐ to 15‐year‐olds were interviewed about their understanding of dependency court on the day of their scheduled court visit. Their feelings about attending their hearings were also assessed, and after their hearing, their understanding of the decisions was examined. Age‐related improvements in children's understanding emerged. Also, children who were more knowledgeable about the legal system were less distressed about attending their hearings, as were younger children who had been in the system a longer time. Finally, a majority of children lacked full or accurate understanding of what actually happened during their hearings. Findings have implications for children's participation in legal proceedings and the development of interventions to facilitate children's legal understanding. Copyright © 2009 John Wiley & Sons, Ltd.
Violent offenses associated with co‐occurring substance use and mental health problems: Evidence from CJDATS
Authors: Sacks Stanley , Cleland Charles M. , Melnick Gerald , Flynn Patrick M. , Knight Kevin , Friedmann Peter D. , Prendergast Michael L. , Coen Carrie
Published: January 2009

The present study examines the relationship between substance use, mental health problems, and violence in a sample of offenders released from prison and referred to substance abuse treatment programs. Data from 34 sites (n = 1,349) in a federally funded cooperative, the Criminal Justice Drug Abuse Treatment Studies (CJDATS), were analyzed. Among parolees referred to substance abuse treatment, self‐reports for the six‐month period before the arrest resulting in their incarceration revealed frequent problems with both substance use and mental health. For most offenders with substance use problems, the quantity of alcohol consumed and the frequency of drug use were associated with a greater probability of self‐reported violence. Mental health problems were not indicative of increases in violent behavior, with the exception of antisocial personality problems, which were associated with violence. The paper emphasizes the importance of providing substance abuse treatment in relation to violent behavior among offenders with mental health problems being discharged to the community. Copyright © 2009 John Wiley & Sons, Ltd.
The Structural Diversity of Acidic Lipopeptide Antibiotics
Authors: Strieker Matthias , Marahiel Mohamed A.
Published: January 2009

Resisting resistance: Acidic lipopeptide antibiotics are very effective in fighting multidrug‐resistant Gram‐positive bacteria, including methicillin‐resistant Staphylococcus aureus and vancomycin‐resistant enterococci. The structural diversity of these lipopeptides, including daptomycin, which is already in clinical use, is depicted in this review. Engineering approaches to yield novel lipopeptides and tailoring events facilitating structural variety are presented.

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Acidic lipopeptide antibiotics are a new class of potent antibiotics, which includes daptomycin, A54145, calcium‐dependent antibiotics (CDAs), friulimicins/amphomycins, laspartomycin/glycinocins and others. The importance of this novel class is exemplified by the success story of the clinically approved daptomycin, which is used for the treatment of skin infections and bacteremia caused by multidrug‐resistant bacteria, including methicillin‐resistant Staphylococcus aureus and vancomycin‐resistant enterococci. The potency of acidic lipopeptides is inherent in their chemical structure. The nonribosomally synthesized peptide cores consist of eleven to 13 amino acids, which are rigidified by the formation of a ten‐membered ring. An N‐terminal fatty acid, which facilitates insertion into the lipid bilayer of bacterial membranes, completes the structure. All these antibiotics contain multiple nonproteinogenic amino acids as well as different lipid tails; this yields remarkable structural diversity. This review summarizes the observed structural variety through a detailed description of the composition of the acidic lipopeptides. Furthermore, engineering approaches towards novel lipopeptides are presented. Recent discoveries in the field of tailoring enzymes, which enable structural plurality mainly by amino and fatty acid precursor biosynthesis, are highlighted.
Residual Dipolar Couplings in Short Peptidic Foldamers: Combined Analyses of Backbone and Side‐Chain Conformations and Evaluation of Structure Coordinates of Rigid Unnatural Amino Acids
Authors: Schmid Markus B. , Fleischmann Matthias , D'Elia Valerio , Reiser Oliver , Gronwald Wolfram , Gschwind Ruth M.
Published: January 2009

A flexible tool for rigid systems. Residual dipolar couplings (RDCs) have proven to be valuable NMR structural parameters that provide insights into the backbone conformations of short linear peptidic foldamers, as illustrated here. This study demonstrates that RDCs at natural abundance can provide essential structural information even in the case of short linear peptides with unnatural amino acids. In addition, they allow for the detection of proline side‐chain conformations and are used as a quality check for the parameterizations of rigid unnatural amino acids.

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Automated left ventricular delineation in X‐ray angiograms: A validation study
Authors: Oost Elco , Oemrawsingh Pranobe , Reiber Johan H. , Lelieveldt Boudewijn
Published: January 2009

Objectives:

Recently an automated analysis approach for left ventricular (LV) X‐ray angiographic studies was proposed. This particular study aims to assess the clinical potential of this approach.

Background:

Over the past 30 years much research has been carried out to develop a technique with automated contour detection of the LV outline in the end‐diastolic (ED) and end‐systolic (ES) phases. Very few have made it into clinical practice. Our latest approach is based on innovative model‐based image processing techniques.

Methods:

Two expert cardiologists analyzed 30 patient studies both by contouring the LV manually and by using the proposed automated methodology. In the latter procedure the experts were allowed to edit the automatically generated contours manually. The manual, automatic, and edited automatic contours were compared, focusing on accuracy, workflow efficiency, and inter‐ and intra‐observer variabilities.

Results:

No significant differences between the automatically derived and manual LV volumes were observed. The average patient study analysis time was reduced by 26%, from 4.2 to 3.1 min. When editing was required, 19% of the ED and 25% of the ES contour length needed manual correction. Furthermore, a reduction in inter‐observer variability of 12.4% was observed.

Conclusions:

Using the proposed automated methodology for X‐ray LV angiographic study analysis, a considerable reduction in required analysis time and manual effort is achieved. Because the acquired results are of clinically acceptable quality and the inter‐ and intra‐observer variabilities are reduced, this automated approach has the potential to optimize the analysis workflow for LV X‐ray angiography in clinical practice. © 2009 Wiley‐Liss, Inc.
The Effect of a Complexed Lithium Cation on a Norcarane‐Based Radical Clock
Authors: Jäger Christof M. , Hennemann Matthias , Clark Timothy
Published: January 2009

Making radical clocks run faster: Complexation of the 2‐norcaranyl radical to the “naked” lithium cation lowers the barrier to the “radical‐clock” rearrangement (see picture). However, model calculations on the mechanism of the hydroxylation of norcarane with cytochrome P450 suggest that no such electrostatic catalysis can be expected at the active site of the enzyme.

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Density‐functional theory (DFT) and ab initio calculations have been used to investigate the effect of a complexed lithium cation on the radical‐clock rearrangement of the 2‐norcaranyl radical to the 3‐cyclohexenylmethyl radical. As found earlier for ring‐closing radical clocks, complexation with a metal ion leads to a significant lowering of the barrier to rearrangement. DFT calculations on a model for the norcaranyl clock in cytochrome P450 confirm the two‐state reactivity proposal of Shaik et al. and indicate that the porphyrin exerts little or no electrostatic effect on the rearrangement barrier.
Synthesis and Optoelectronic Properties of Nanometer‐Sized and Highly Soluble Homocoupled Oligodiacetylenes
Authors: Pilzak Gregor S. , Baggerman Jacob , van Lagen Barend , Posthumus Maarten A. , Sudhölter Ernst J. R. , Zuilhof Han
Published: January 2009

Color and shape of oligodiacetylenes: We synthesized a series of highly soluble homocoupled oligodiacetylenes (HODAs). The color of these oligomers is dependent on the molecular length and aggregation state (see picture). The optical properties of these materials were studied by using both steady‐state and time‐resolved spectroscopic techniques.

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A new series of pure, nanometer‐sized and highly‐soluble homocoupled oligodiacetylenes (HODA) consisting of two symmetrical oligodiacetylene units was synthesized with high yield and on a multi‐milligram scale under mild, catalytic Sonogashira conditions. The λmax and the εmax of absorption for these HODAs show an increase with the chain elongation. The λmax converges to 450 nm for the longest members of the series at micromolar concentration and to 462 nm for thin drop‐casted films. An additional red‐shifted absorption is observed in the solid state and in solution at low temperatures, which is caused by aggregation. The λmax of the fluorescence emission increases with the chain length and reaches 492 nm for the longest oligomer. The fluorescence quantum yield has its maximum for the shortest oligomer and decreases rapidly for the longer ones. A similar trend is found for the fluorescence lifetime with a maximum of 100 ps for the homocoupled monomer. The rotational correlation time shows a linear increase with the oligomer length. This reveals a significant persistence length and indicates that the HODA molecules are fully stretched molecular rods (up to 8.2 nm).
Stereoselective Synthesis of the Functionalized C2–C10 Fragment of Clavulactone
Authors: ZHOU Zuozhong , SUO Dong , YANG Zhenyu , CHEN Lin , HU Taishan , YAO Zhujun
Published: January 2009

A stereoselective synthesis of all functionalized C2–C10 fragment 13 of the antitumor marine natural product clavulactone was accomplished, starting from the commercially available 3‐methylglutaric acid anhydride. Desymmetrization of 3‐methylglutaric acid anhydride with (S)‐α‐phenylethanamine was successfully employed as a key step to embed the isolated C8‐methyl group with the correct absolute configuration (99% de). The C3–C4 cis‐double bond was stereospecifically furnished by an RCM (ring‐closing metathesis) approach. Fragment 13 contains all preset functionalities and will be a useful precursor for the convergent total synthesis of clavulactone.
Metal‐mediated gem‐Difluoroallylation of N‐Acylhydrazones: Highly Efficient Synthesis of α,α‐Difluorohomoallylic Amines
Authors: YUE Xuyi , QIU Xiaolong , QING Fengling
Published: January 2009

Indium‐mediated gem‐difluoroallylation of aldehyde‐derived N‐acylhydrazones 1a–1q and 4a–4g with 3‐bromo‐3,3‐difluoropropene 2 afforded α,α‐difluorohomoallylic hydrazides 3a–3q and 5a–5g in high yields, respectively. Functional groups such as nitro, phenolic hydroxyl, benzyloxy and even C=C bonds of α,β‐unsaturated aldehydes were compatible under this mild and operationally simple gem‐difluoroallylic reaction condition. By means of substitution of Zn powder for indium, gem‐difluoroallylation of ketone‐derived N‐acylhydrazones 6a–6d also provided the corresponding α,α‐difluorohomoallylic hydrazides 7a–7d in medium yields. The N–N bond cleavage of the hydrazide 3a proceeded smoothly to give the corresponding primary gem‐difluorohomoallylic amine 8, which could be converted to gem‐difluoro‐δ‐substituted α,β‐unsaturated lactam 11 via acryloylation followed by ring closing metathesis (RCM) reaction.
Enantioselective Fluorescent Sensor Based on Calix[4]arene and S‐Binol for the Recognition of N‐Boc‐glutamate
Authors: HU Chenguang , HUANG Xiaohuan , CHEN Zhihong , HE Yongbing
Published: January 2009

A new chiral macrocyclic receptor 4 based on calix[4]arene and S‐binol units was synthesized. The binding properties for anions were examined by fluorescence and 1H NMR spectra. The results of non‐linear curve fitting indicated that the receptor 4 formed a 1:1 stoichiometry complex with N‐Boc‐L‐ or D‐glutamate by multiple hydrogen bonding interactions, exhibiting a good enantioselective fluorescent recognition for the enantiomers of N‐Boc‐glutamate. The enantioselectivity: Kass(L)/Kass(D)=4.65. The different fluorescent response indicates that the receptor 4 could be used as a fluorescent chemosensor for N‐Boc‐glutamate.
Asymmetric Conjugate Addition of Unmodified Cyclic Ketones to Nitroolefins Using Aminophosphonate as the Organocatalyst
Authors: CHEN Gang , WANG Zheng , DING Kuiling
Published: January 2009

α‐Aminophosphonates are an important class of compounds with diverse and useful biological activities. Despite that their structues are similar to that of proline, however, chiral cyclic α‐aminophosphonates have found little applications in catalytic asymmetric synthesis. In this paper, an enantiopure α‐aminophosphonate has been synthesized and was found to be effective as a chiral organocatalyst for the asymmetric conjugate addition of cycloketones to β‐nitrostyrenes. With a catalyst loading of 20 mol% and in the presence of 10 mol% of CF3COOH as a cocatalyst, the Michael adducts could be obtained with varying degrees of diastereo‐ and enantioselectivities (up to 97:3 and 90% ee respectively) under solvent‐free conditions.
Stereocontrolled Synthesis of (E)‐β,γ‐Unsaturated Esters via Palladium‐Catalyzed Cross‐Coupling of (E)‐Alkenylboronic Acids with α ‐Bromoacetic Esters
Authors: DUAN Yazhen , ZHANG Jianshe , YANG Jun , DENG Minzhi
Published: January 2009

The cross‐coupling reaction of trans‐alkenylboronic acids with ???α????‐bromoacetic esters was firstly studied. It was found that using Pd(OAc)2 as catalyst, a bulky electron‐rich phospine, (2‐dicyclohexylphospino‐biphenyl) as ligand, the reaction can be readily accomplished to give specific (E)‐???β???????? γ????‐unsaturated esters in high yields.
An Efficient Guanylation of Aromatic Amines Catalyzed by Samarium Diiodide
Authors: ZHU Xuehua , XU Fan , SHEN Qi
Published: January 2009

An efficient guanylation of aromatic amine with carbodiimide in the presence of a catalytic amount of samarium diiodide, a Lewis‐acid type precatalyst readily accessible, was developed. The reaction was carried out under mild conditions giving a variety of guanidines in good to excellent yields.
Automatic Identification of Antibodies in the Protein Data Bank
Authors: LI Xun , WANG Renxiao
Published: January 2009

An automatic method has been developed for identifying antibody entries in the protein data bank (PDB). Our method, called KIAb (Keyword‐based Identification of Antibodies), parses PDB‐format files to search for particular keywords relevant to antibodies, and makes judgment accordingly. Our method identified 780 entries as antibodies on the entire PDB. Among them, 767 entries were confirmed by manual inspection, indicating a high success rate of 98.3%. Our method recovered basically all of the entries compiled in the Summary of Antibody Crystal Structures (SACS) database. It also identified a number of entries missed by SACS. Our method thus provides a more complete mining of antibody entries in PDB with a very low false positive rate.
Synthesis, QSAR Study and Optimization of Propiophenone Oxime Derivatives
Authors: CHEN Liang , HUANG Ying , XIE Wei , CAO Jin , NI Changchun , SHEN Zhou , LI Xiuli , ZHANG Yibin , SHEN Tianxiang , YU Fei , LIU Bin , YUAN Liping , YAO Jianhua
Published: January 2009

A method combining chemical and biological experiments and computer‐aided molecular design was used to optimize lead compounds with inhibiting activity against Sphaerotheca fuliginea. 44 propiophenone oxime derivatives were synthesized by 3‐amino‐1‐arylpropan‐1‐one oxime and halohydrocarbon. The results of biological test showed that most of these compounds had inhibiting activity against Sphaerotheca fuliginea. QSAR study was done based on the experimental data of the 44 compounds. CoMFA (rCV2, S and r2 are 0.577, 0.258 and 0.962, respectively) and CoMSIA (rCV2, S and r2 are 0.583, 0.343 and 0.932 respectively) models were contributed and employed to design three new lead compounds whose prediction carcinogenic and mutagenic toxicities show impossibility. The performances of the two models are satisfied because the test results showed that their prediction activity and observed activity are corresponding.
Xanthones from the Bark of Garcinia xanthochymus and Their 1,1‐Diphenyl‐2‐picrylhydrazyl Radical‐Scavenging Activity
Authors: ZHONG Fangfang , CHEN Yu , WANG Ping , FENG Huijin , YANG Guangzhong
Published: January 2009

Five new xanthones, garcinenone A (1), B (3), C (4), D (7) and E (8), along with 7 known compounds were isolated from the EtOAc‐soluble extract of the bark of Garcinia xanthochymus, and their structures were elucidated by spectroscopic methods, especially 2D‐NMR techniques. Jacareubin (2), 1,4,6‐trihydroxy‐5‐methoxy‐7‐(3‐methyl‐2‐butenyl)xanthone (6), subeliptenone B (11) and symphoxanthone (12) were obtained from this plant for the first time. The isolated compounds exhibited potent antioxidant activity in the 1,1‐diphenyl‐2‐picrylhydrazyl (DPPH) radical scavenging test with IC50 values in the 6.0–23.2 µmol/L. These results suggested that G. xanthochymus could be a promising rich source of natural antioxidant.
Photocatalytic Degradation of Dicofol and Pyrethrum with Boric and Cerous Co‐doped TiO2 under Light Irradiation
Authors: GONG Lifen , ZOU Jing , ZENG Jinbin , CHEN Wenfeng , CHEN Xi , WANG Xiaoru
Published: January 2009

Boric and cerous co‐doped nano titanium dioxide (B/Ce co‐doped TiO2) was synthesized using a sol‐gel technique, which involved the hydrolyzation of tetrabutyl titanate with the addition of boric acid and cerous nitrate. The B/Ce co‐doped TiO2 was employed for the photocatalytic degradation of dicofol, cyfluthrin and fenvalerate under light irradiation. XRD, TEM, FT‐IR and UV‐Vis DRS methods were used to characterize the crystalline structure. Experimental results showed that only the anatase signal phase was found for B/Ce co‐doped TiO2, but multiplicate phases, including anatase, rutile and less brookite phases, were identified both in the pure TiO2 nanoparticles and Ce‐doped TiO2 nanoparticles. The band gap value of B/Ce co‐doped nano TiO2 was narrower than that of undoped nano TiO2. Compared to undoped TiO2, a stronger absorption in the range of 420 to 850 nm was found for B/Ce co‐doped nano TiO2, which presented a higher photocatalytic activity in the degradation of dicofol, cyfluthrin and fenvalerate than both Ce doped nano TiO2 and pure nano TiO2 under the same light irradiation.
Vanillezucker oder Vanillinzucker?
Authors: Sommer Katrin , Andreß Stefan , Kakoschke Annette , Wieczorek Robert , Hanisch Simone , Hanss Jan
Published: January 2009

Jedes Jahr werden weltweit ca. 2.000 Tonnen Vanillefrucht und ca. 12.000 Tonnen Vanillin produziert, um den Bedarf an dieser Aromanote zu decken ‐ sei es für Vanille‐Eis, Vanillin‐Zucker oder Cola. Der vorliegende Beitrag bietet sowohl fachliche Hintergrundinformationen als auch schulpraktische Möglichkeiten der experimentellen Erschließung des Themas „Vanille vs. Vanillin”︁ für die unterrichtliche Umsetzung. Es wird dabei die erfolgreiche Synthese von Vanillin aus Ligninsulfonsäure ebenso beschrieben wie Möglichkeiten der experimentellen Erschließung der Struktur von Vanillin. Anhand der Produkte „Vanillezucker”︁ und „Vanillinzucker”︁ erfolgt sowohl ein qualitativer Nachweis von Vanillin durch dünnschichtchromatographische Untersuchung als auch die quantitative Bestimmung von Vanillin im Vanillinzucker mittels Säure‐Base‐Titration.
The prognostic value of pretreatment CA 125 in patients with advanced ovarian carcinoma
Authors: Zorn Kristin K. , Tian Chunqiao , McGuire William P. , Hoskins William J. , Markman Maurie , Muggia Franco M. , Rose Peter G. , Ozols Robert F. , Spriggs David , Armstrong Deborah K.
Published: January 2009

BACKGROUND:

The objective of the current study was to determine the prognostic significance of a pretreatment serum CA 125 level in patients with advanced epithelial ovarian carcinoma (EOC) who received treatment with a standard chemotherapy regimen.

METHODS:

Patients with International Federation of Gynecology and Obstetrics stage III/IV ovarian carcinoma who were on 1 of 7 Gynecologic Oncology Group (GOG) phase 3 trials and received treatment with a standard regimen of intravenous cisplatin and paclitaxel were included. A Cox regression model was used to assess the impact of CA 125 levels drawn before the initiation of chemotherapy on progression‐free survival (PFS) both overall and by subgroup, including surgical debulking status, disease stage, and histologic subtype.

RESULTS:

In total, 1299 patients who were on the cisplatin/paclitaxel arms of the GOG trials were eligible. The median CA 125 level was 246 U/mL. Only 7.6% of patients had a normal CA 125 level (≤35 U/mL). The lowest median CA 125 level was observed in the group with mucinous tumors; however, 69% of women who had mucinous tumors had abnormal CA 125 levels. Shorter PFS was observed with increasing CA 125 and persisted in multivariate analysis. Overall and in the serous subgroup, a 1‐fold increase in CA 125 level was associated with a 7% increase in the hazard of disease progression (P < .001). This association was even more pronounced in patients who had stage III disease that was debulked to microscopic disease (15%; P = .003) and in patients who had endometrioid tumors (17%; P = .001).

CONCLUSIONS:

A normal CA 125 level in the setting of advanced EOC was rare even after surgical debulking. The pretreatment CA 125 level was an independent predictor of PFS in patients with advanced EOC who received a standard chemotherapy regimen, particularly in the setting of disease that was debulked to a microscopic residual and in the serous or endometrioid subtypes. Cancer 2009. © 2009 American Cancer Society.
Genetic polymorphisms of CYP2D6*10 and CYP2C19*2,*3 are not associated with prognosis, endometrial thickness, or bone mineral density in Japanese breast cancer patients treated with adjuvant tamoxifen
Authors: Okishiro Masatsugu , Taguchi Tetsuya , Jin Kim Seung , Shimazu Kenzo , Tamaki Yasuhiro , Noguchi Shinzaburo
Published: January 2009

BACKGROUND:

The authors investigated the impact of the genetic polymorphisms cytochrome P450 (CYP) family 2, subfamily D, polypeptide 6, allele *10 (CYP2D6*10) and CYP family 2, subfamily C, polypeptide 19, allele *2,*3 (CYP2C19*2,*3) on disease recurrence in patients with breast cancer who received adjuvant tamoxifen and evaluated the impact of those polymorphisms on endometrial thickness, bone mineral density (BMD), and serum total cholesterol levels.

METHODS:

Patients with primary breast cancer (n=173) who had hormone receptor‐positive tumors and who also received adjuvant tamoxifen were included in the current study. Genetic polymorphisms of CYP2D6*10 and CYP2C19*2,*3 were analyzed.

RESULTS:

Recurrence‐free survival (RFS) rates did not differ significantly between patients with the CYP2D6 *10/*10 genotype (n=40) and patients with the CYP2D6 wild‐type (wt)/wt or wt/*10 genotype (n=133) or between patients with the CYP2C19 *2/*2, *2/*3, or *3/*3 genotypes (n=41) and patients with the CYP2C19 wt/wt, wt/*2, or wt/*3 genotype (n=132). Multivariate analysis indicated that, even after adjustment for well established prognostic factors, these CYP2D6 or CYP2C19 genotypes were not associated significantly with the RFS rate. Moreover, these genotypes did not affect endometrial thickness, BMD, or total cholesterol levels 1 year after the start of tamoxifen treatment.

CONCLUSIONS:

Neither the CYP2D6 *10/*10 genotype nor the CYP2C19 genotype is likely to have a clinically significant impact on prognosis, endometrial thickness, BMD, or total cholesterol levels in Japanese patients with breast cancer who are treated with adjuvant tamoxifen. Cancer 2009. © 2009 American Cancer Society.
Carbon ion radiotherapy for pediatric patients and young adults treated for tumors of the skull base
Authors: Combs Stephanie E. , Nikoghosyan Anna , Jaekel Oliver , Karger Christian P. , Haberer Thomas , Münter Marc W. , Huber Peter E. , Debus Jürgen , Schulz‐Ertner Daniela
Published: January 2009

BACKGROUND:

The current study was conducted to evaluate the outcome of carbon ion radiotherapy (RT) in children and young adults with skull base chordomas and chondrosarcomas.

METHODS:

Between 1997 and 2007, 394 patients were treated with carbon ion RT at Gesellschaft für Schwerionenforschung in Darmstadt, Germany. Of these patients, 17 patients were aged ≤21 years. Seventeen of these young patients were treated for chordoma or low‐grade chondrosarcoma of the skull base and were analyzed in this study. Irradiation was performed after primary diagnosis in 14 patients (82%) and for recurrent tumors in 3 patients (18%). The authors applied a median total dose of 60 gray equivalents (Gy E) (range, 60‐66.6 Gy E) in a fractionation of 7 × 3 Gy E per week of carbon ion RT using the raster scan technique. All patients were observed prospectively on a regular basis after carbon ion RT.

RESULTS:

The median follow‐up time was 49 months. Treatment was well tolerated without severe side effects and could be completed on an outpatient basis in all patients without interruptions. One patient with chordoma developed tumor progression at 60 months after carbon ion RT. All other patients demonstrated no signs of tumor progression during follow‐up.

CONCLUSIONS:

Despite its promising outcome in children and young adults with chordomas and chondrosarcomas, further evaluation in a larger patient collective is required. Randomized studies comparing the outcome after carbon ion RT with proton RT are especially needed to evaluate the role of particle beams in the treatment of skull base tumors in children and young adults. Cancer 2009. © 2009 American Cancer Society.
Accuracy of clinical evaluation of locally advanced breast cancer in patients receiving neoadjuvant chemotherapy
Authors: Prati Raquel , Minami Christina A. , Gornbein Jeff A. , Debruhl Nanette , Chung Debbie , Chang Helena R.
Published: January 2009

BACKGROUND:

Physical examination (PE), mammography (MG), breast magnetic resonance imaging (MRI), fluorodeoxyglucose positron emission tomography (PET), and pathologic evaluation are used to assess primary breast cancer. To the authors' knowledge, their accuracy has not been well studied in patients receiving neoadjuvant chemotherapy. Accuracies of each modality in tumor and lymph node assessment in patients with T3/T4 tumors receiving neoadjuvant chemotherapy were compared.

METHODS:

Forty‐five patients of a prospective clinical trial studying T3‐T4M0 tumors were included. Patients received neoadjuvant chemotherapy: docetaxel/carboplatin with or without trastuzumab before and/or after surgery (depending on HER‐2/neu status and randomization). Tumor measurements by PE, MG, and MRI and lymph node status by PE and PET were obtained before and after neoadjuvant chemotherapy. Concordance among different clinical measurements was assessed and compared with the tumor and lymph node staging by pathology. Spearman correlation (r) and root mean square error (RMSE) were used to measure the accuracy of measurements among all modalities and between modalities and pathologic tumor size.

RESULTS:

Compared with the tumor size measured by PE, MRI was more accurate than MG at baseline (r = 0.559, RMSE = 35.4% vs r = 0.046, RMSE = 66.1%). After neoadjuvant chemotherapy, PE correlated better with pathology than MG or MRI (r = 0.655, RMSE = 88.6% vs r = 0.146, RMSE = 147.1% and r = 0.364, RMSE = 92.6%). Axillary lymph node assessment after neoadjuvant chemotherapy demonstrated high specificity but low sensitivity by PET and PE.

CONCLUSIONS:

Findings suggested that MRI was a more accurate imaging study at baseline for T3/T4 tumor, and PE correlated best with pathology finding. PET and PE both correctly predicted positive axillary lymph nodes but not negative lymph nodes. Cancer 2009. © 2009 American Cancer Society.
Decoupling 2D Inter‐ and Intrachain Energy Transfer in Conjugated Polymers
Authors: Shekhar Shashank , Aharon Eyal , Tian Nan , Galbrecht Frank , Scherf Ullrich , Holder Elisabeth , Frey Gitti L.
Published: January 2009

Intercalation in layered SnS2 of blue‐emitting polyfluorene chains with known concentrations of fluorenone sterically hinders 3D polymer aggregation and π–π interchain interactions. Monitoring the fluorene‐to‐fluorenone energy transfer in quasi‐2D polymer monolayers (see schematic diagram) reveals that 2D energy transfer in conjugated polymers is mainly an interchain process.

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The dimensionality of conjugated polymer systems plays an important role in energy‐transfer processes, and 1D and 2D energy transfer of excitations are typically much slower than that between π‐stacked chains within a 3D polymeric solid. However, whether 2D energy transfer in conjugated polymers occurs mainly along polymer chains (intrachain), or between in‐plain‐adjacent polymer chains (interchain), has yet to be determined due to the difficulty of experimentally decoupling inter‐ and intrachain interaction in a 2D polymer system. This can be achieved by incorporating conjugated polymer chains into the planar galleries of layered matrices which sterically hinder polymer aggregation and π–π interchain interactions. Here, pristine blue‐emitting polyfluorene chains and polyfluorene chains with known concentrations of green‐emitting on‐chain fluorenone defects are either separately or collectively incorporated into layered SnS2. X‐ray powder diffraction of the composite films confirms incorporation of the polymer chains into the layered galleries. Monitoring the fluorene‐to‐fluorenone energy transfer as a function of fluorenone concentration and distribution in the layered galleries allows differentiation between inter‐ and intrachain fluorene–fluorenone energy transfer. It is found that, 2D energy transfer in conjugated polymers follows mainly an interchain process, despite the absence of π–π interchain interactions.
Group IV Coordination Chemistry of a Tetradentate Redox‐Active Ligand in Two Oxidation States
Authors: Blackmore Karen J. , Lal Neetu , Ziller Joseph W. , Heyduk Alan F.
Published: January 2009

The redox‐active ligand N,N′‐bis(3,5‐di‐tert‐butyl‐2‐phenoxy)‐1,2‐phenylenediamide [N2O2red]4– reacts with group IV metal salts to form six‐ and seven‐coordinate complexes [N2O2red]MLn (M = Ti, L = py, n = 2; M = Zr, Hf, L = thf, n = 3). The redox‐active ligand occupies four equatorial coordination sites in these complexes. In the case of the zirconium and hafnium complexes, two axial solvent molecules coordinate to the metal center with a third solvent molecule coordinating in the equatorial plane. In the case of the smaller titanium metal center, only two pyridine solvent molecules coordinate to the metal atom, leaving an open coordination site. All three complexes react with halogen oxidants to afford oxidative addition products [N2O2ox]MCl2Ln (M = Ti, n = 0; M = Zr, Hf, L = thf, n = 1), in which the redox‐active ligand is oxidized by two electrons to the cyclohexadienediimine state. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)
Effect of SatSatSat and SatOSat on crystallization of model fat blends
Authors: Vereecken Jeroen , Foubert Imogen , Smith Kevin W. , Dewettinck Koen
Published: January 2009

In this study, the crystallization and melting properties of six different fat blends with the same saturated fat content (30%) but with a varying content of trisaturated and disaturated triacylglycerols were investigated using pulsed NMR, DSC and polarized light microscopy. Blends were either palmitic (P) or stearic (S) based, and were combinations of SatSatSat‐rich (Sat = saturated) and SatOSat‐rich (O = oleic) vegetable oils with high‐oleic sunflower oil. The DSC results suggested that PPP forms mixed crystals with POP, leading to a better seeding of the crystallization process than did SSS with SOS. Some blends showed a two‐step crystallization, which can be explained by polymorphism. Stop‐and‐return DSC results suggested an initial crystallization into an unstable polymorph followed by polymorphic transformation during the crystallization for those blends with significant amounts of SatSatSat. Polymorphic transformation was not seen for the blends with low SatSatSat. However, the microstructure of such blends changed dramatically during storage, while the microstructure of the blends with the higher SatSatSat content did not.
On the quality control of ‘olive paste’, a specialty based on olives and olive oil
Authors: Anniva Christina , Tsimidou Maria Z.
Published: January 2009

‘Olive paste’ is a preserved food gaining popularity as a gourmet product. Its quality depends on that of the major ingredients, table olives (green or black) and virgin olive oil, as well as on the changes occurring to the constituents of the latter during preparation and storage. In this view, our attention was focused on the characteristics of the lipid fraction (l.f.) of a great number of commercial products after a careful search in retail markets and the web. Ultraviolet absorbance values (K232, K270) of the l.f., a criterion set for edible and non‐edible olive oil oxidative status due to paste heat treatment during pasteurization, could not support the label information regarding the quality of the oil used. On the contrary, the content of α‐tocopherol (˜250 mg/kg l.f. or ˜50 mg/kg paste) was a strong indication of good‐quality major ingredients. Within each brand, consistency with labeling was checked through squalene (higher content in products containing higher amounts of olive oil) or β‐carotene determination (higher levels in preparations containing red pepper). For green olive paste samples, the values of the ratio pheophytin a/pyropheophytin a may be used to monitor the shelf life of the product. The findings support routine quality control of the new product.
Effect of ingredients on oxidative stability of fish oil‐enriched drinking yoghurt
Authors: Nielsen Nina Skall , Klein Anna , Jacobsen Charlotte
Published: January 2009

The oxidative stabilities of fish oil‐enriched milk and fish oil‐enriched drinking yoghurt were compared by following the development of lipid oxidation in plain milk, plain yoghurt and yoghurt to which ingredients present in drinking yoghurt were added one by one. All samples were enriched with 1 wt‐% fish oil. After 3 weeks of storage, development of peroxide values, volatile secondary oxidation products and fishy off‐flavors were much more pronounced in the milk compared to any of the yoghurt samples, irrespective of any added ingredients used to prepare flavored drinking yoghurt. Thus, pectin, citric acid or glucono‐delta‐lactone did not affect the oxidative stability of fish oil‐enriched yoghurt emulsions. Furthermore, the fruit preparation and added sugar did not lead to increased antioxidative activity. It is concluded that yoghurt as the dairy component in the fish oil‐enriched emulsion was responsible for the remarkably high oxidative stability and was able to protect the n‐3 PUFA against oxidative deterioration. It should be considered that this strong antioxidative effect of yoghurt might mask potential antioxidative effects of the other ingredients in the drinking yoghurt.
DFT Studies on Double Hydrogen Bond Catalysis of Reactions of Distinct Polarity
Authors: Gómez‐Bengoa Enrique
Published: January 2009

The Diels–Alder cycloaddition and the enamine‐aldol reactions catalyzed by double‐site hydrogen‐bond donors were computationally studied at the B3LYP and MP2/6‐311++G** levels. The comparison of bifurcated and cooperative H‐bonding activation of the electrophile in both reactions with 1,3‐propanediol, 1,4‐butanediol, glycolic acid and two molecules of methanol strongly suggests that the activation mode depends on the electronic features of the carbonyl oxygen atom in the H‐bond acceptor. The bifurcated arrangement of the hydrogen‐bond donors is predicted to be favoured as the polarity of the reaction increases. Consequently, the transition states of the Diels–Alder reaction are better stabilized by a cooperative interaction with the diols and those of the more polar enamine‐aldol reaction by a bifurcated interaction. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)
Integrated microdevice for preconcentration and separation of a wide variety of compounds by electrochromatography
Authors: Proczek Gaelle , Augustin Violaine , Descroix Stephanie , Hennion Marie‐Claire
Published: January 2009

An integrated microdevice was developed to couple on‐chip SPE to separation by channel electrochromatography. An acrylate‐based monolith was synthesized within a glass microdevice by photoinitiated polymerization. It was used for both separation and preconcentration by direct injection on the head of the stationary phase or by confining the preconcentration step in a given zone of the stationary phase. The composition of the polymerization mixture was chosen to achieve a monolithic material containing both hydrophobic and charged moieties to ensure an electroosmotic flow for separation. As a consequence the extraction procedure occurs via hydrophobic and ionic interactions. Neutral, ionizable and charged compounds were successfully preconcentrated and separated within the microdevice through electrochromatographic mechanisms, highlighting the versatility of this device. The performance of the integrated microdevice was demonstrated with the preconcentration and separation of a mixture of PAHs for which a signal enhancement factor (SEF) of 270 was achieved within 120 s of preconcentration. In the case of charged and ionizable compounds, according to the electrolyte composition, contributions of both reverse‐phase and ion‐exchange mechanisms were used to perform effective electrochromatographic preconcentration. A SEF of 250 was obtained for the model‐charged compound within 20 s of preconcentration. Finally, the potentials of on‐chip preconcentrate and separate both neutral and ionized compounds have been demonstrated using a mixture of model compounds.
CE‐based detection of methicillin‐resistant Staphylococcus aureus
Authors: Naikare Hemant , Ramachandran Akhilesh , Goad David , Clarke Jean , Clarke Cyril
Published: January 2009

Rapid and sensitive detection of methicillin‐resistant Staphylococcus aureus is crucial for effective treatment and control of clinical infections caused by this bacterium. The goal of this study is to develop a CE‐based detection method for multiplexed identification of a femA sequence specific for S. aureus and a unique mecA sequence encoding methicillin resistance. Blood samples spiked with known concentrations of bacteria were used for testing. Crude cell lysates were prepared by treating the spiked blood samples with DNazol Direct reagent and used as the template for isothermal amplification of mecA and femA genes. The amplified gene products then underwent a cycling probe reaction (CPR)‐based assay to generate a short fluorophore‐labeled oligonucleotide for detection in a CZE‐LIF system. The assay enables a gene‐specific fluorophore‐labeled DNA–RNA–DNA chimeric probe to hybridize with complementary target in the presence of RNase H enzyme. The RNase H enzyme specifically cleaves probe RNA residues of the duplex, releasing a fluorophore fragment for detection and the target for recycling and hybridization with another chimeric probe. Intact and cleaved probe fragments were separated and detected using a CZE‐LIF system. The limit of detection for isothermal amplification and CPR‐CZE‐LIF was ∼104 colony‐forming units of bacteria/mL of blood. This method accurately detects methicillin‐resistant S. aureus within 3 h.
Selective enrichment of albumin in biological samples by CE using segmental filling with sodium octyl sulfate in the background electrolyte
Authors: Lin Chin‐Yu , Tseng Wei‐Lung
Published: January 2009

This paper shows that in CE, the peak efficiency and effective electrophoretic mobility of HSA and BSA were significantly enhanced by using a short plug (8 nL) of 1% w/w sodium octyl sulfate (SOS) and 1% w/v dextran sulfate as the additive. However, under identical conditions, other proteins did not exhibit the same phenomena. When the concentration of SOS was increased to 1.0% w/w SOS, a broad peak that corresponded to HSA transformed to a sharp peak. When the SOS concentration was more than 3.0% w/w, there was no shift in the effective electrophoretic mobility of HSA (10 μM), indicating that the binding of SOS to HSA is saturated. Through the specific interaction between SOS and HSA, the selective sweeping of HSA was accomplished using a short plug (24 nL) of 1% w/w SOS, followed by the injection of 190 nL of the sample. The excellent peak efficiency was still obtained for HSA and BSA upon the injection of a large‐volume sample. As a result, the LOD for HSA (S/N=3)was 0.1 nM. In contrast to the normal injection without the SOS plug, approximately, a 4000‐fold increase in the sensitivity of HSA was obtained by using the sweeping method. The proposed method has been successfully applied for the quantification of HSA in urine and erythrocytes as well as the quantification of BSA in milk.
The combination of flow injection with electrophoresis using capillaries and chips
Authors: Lü Wen‐juan , Chen Yong‐lei , Zhu Jin‐hua , Chen Xing‐guo
Published: January 2009

The technique of combined flow injection CE (FI‐CE) integrates the essential favorable merits of FI and CE. It utilizes the various excellent on‐line sample pretreatments and preconcentration (such as cloud point extraction, SPE, ion‐exchange, dynamic pH junction and head‐column field‐amplified sample stacking technique) of FI, which has the advantages of high speed, accuracy, precision and avoiding manual handling of sample and reagents. Therefore, the coupling of FI‐CE is an attractive technique; it can significantly expand the application of CE and has achieved many publications since its first appearance. The basic principles, instrumental developments and applications of FI‐CE system from 2006 to 2008 are reviewed.
Development of an in‐capillary derivatization method by CE for the determination of chiral amino acids in dietary supplements and wines
Authors: Martínez‐Girón Ana Belén , García‐Ruiz Carmen , Crego Antonio L. , Marina Maria Luisa
Published: January 2009

A fast in‐capillary derivatization method by CE with 6‐aminoquinolyl‐N‐hydroxysuccinimidyl carbamate was developed for the first time for the determination of amino acid enantiomers (arginine, lysine, and ornithine) in dietary supplements and wines. Because of the initial current problems due to the formation of precipitates into the capillary during the derivatization reaction, a washing step with an organic solvent as DMSO between injections was necessary. Different approaches were also investigated to enhance the sensitivity of detection. A derivatization procedure, where plugs of ACN, derivatizing agent (10 mM 6‐aminoquinolyl‐N‐hydroxysuccinimidyl carbamate), and sample in borate (1:1 v/v) were injected in tandem (2, 3, and 6 s, respectively, at 50 mbar), was selected because it enabled to obtain the most sensitive and reproducible results. Appropriate analytical characteristics (linearity, LOD and LOQ, precision, absence of matrix interferences, and accuracy) were obtained for this method. Finally, the optimized method was successfully applied to the determination of the enantiomers of arginine, lysine, and ornithine in food samples of different complexities (dietary supplements and wines).
Separation and detection of isoquinoline alkaloids using MEEKC coupled with field‐amplified sample injection induced by ACN
Authors: Yu Li‐Shuang , Xu Xue‐Qin , Huang Lu , Lin Jin‐Ming , Chen Guo‐Nan
Published: January 2009

New methods based on MEEKC coupling with field‐amplified sample injection (FASI) induced by ACN were proposed for five isoquinoline alkaloids (berberine, palmatine, jatrorrhizine, sinomenine and homoharringtonine) in no salt and high salt sample solution (HS). For the separation of five isoquinoline alkaloids, a running buffer composed of 18 mM sodium cholate, 2.4% v/v butan‐1‐ol, 0.6% v/v ethyl acetate, 10% v/v (or 30% v/v) methanol and 87.0% v/v (or 67% v/v) 5 mM Na2B4O7∼10 mM NaH2PO4 buffer (pH 7.5) was developed. In order to improve the sensitivity, FASI induced by ACN was applied to increase the detection sensitivity. The detection limit was found to be as low as 0.0002 μg/mL in no salt sample solution and 0.062 μg/mL in HS. The method has been applied for the analysis of human urine spiked with analytes, and the assay results were proved to be satisfactory, and also the determination of berberine in urine sample after oral administration berberine.