bluuebunny/crossref_metadata_2025_split huggingface dataset:
Impact of reduction of therapy on infectious complications in childhood acute lymphoblastic leukemia
Authors: Graubner Ulrike B. , Porzig Simone , Jorch Norbert , Kolb Reinhard , Wessalowski Rüdiger , Escherich Gabriele , Janka Gritta E. 
Published: July 2007

AbstractBackgroundInfections are a major cause of morbidity and mortality in childhood acute lymphoblastic leukemia (ALL) and only limited information is available on infectious complications.Patients and MethodsWe investigated infectious complications in 293 children during different treatment phases of the multicenter protocol COALL‐06‐97. We also evaluated whether therapy reduction in prognostically good risk patients receiving either the low risk or high risk treatment arm would lead to fewer infectious complications.ResultsThirty of 293 patients had no infections; 263 patients had 682 infectious complications (median 2, range 1–9), five of them lethal. Two thirds of the infections occurred during periods of neutropenia. The most frequent infectious episodes were fever of unknown origin (FUO): 483/682 (70.8%), microbiologically documented infections (MDI): 100/682 (14.6%), (61 gram‐positive, 36 gram‐negative, 3 fungal isolates), and clinically documented infections (CDI): 99/682 (14.5%). With standard reinduction, 44% low risk and 57% high risk patients had infections versus 26% low risk and 38% high risk patients with reduced reinduction therapy (P < 0.01).ConclusionsMost patients treated with intensive combination therapy for ALL experience one to several serious infections during treatment. The wide range in number of infectious episodes and the lack of infections in a small subset of patients in spite of uniform treatment suggest genetic as well as possibly environmental factors to have a role. Moderate reduction of chemotherapy may significantly reduce the rate of infectious episodes. Pediatr Blood Cancer 2008;50:259–263. © 2007 Wiley‐Liss, Inc.
Self and proxy‐reported health status and health‐related quality of life in survivors of childhood cancer in Uruguay
Authors: Fluchel Mark , Horsman John R. , Furlong William , Castillo Luis , Alfonz Yasmine , Barr Ronald D. 
Published: July 2007

AbstractBackgroundThe incidence of cancer in children in Uruguay is similar to that in industrialized societies but the survival rate is half as great. This study assesses another important measure of treatment effectiveness: the health‐related quality of life (HRQL) of survivors.MethodsAll new patients diagnosed in a 3‐year period were eligible if free of disease for at least 2 years after therapy and at least 7 years of age at the time of study. A sample of convenient subjects for comparison was obtained from schools and clinics for well children. During a 7‐month period, Spanish language interviewer‐administered questionnaires were used to collect Health Utilities Index data from survivors and the comparison group (self‐reports), and from proxies (parents, physicians, and teachers).ResultsOf 113 eligible survivors, 95 (84%) participated together with 96 “control” subjects. Control subjects have a higher mean HRQL utility score than survivors (P < 0.001). The mean score for survivors of acute lymphoblastic leukemia (ALL): 0.72 (n = 49) is higher than the score for survivors of brain tumors: 0.60 (n = 20), as expected. Inter‐rater agreement is highest between survivors and parents, and lowest between controls and physicians or teachers.ConclusionsThe burden of morbidity in survivors of childhood cancer in Uruguay is considerable and greater than that in a comparative group of healthy children. Survivors of ALL have better HRQL than survivors of brain tumors, mirroring experience elsewhere. The level of inter‐rater agreement is related to the degree of familiarity of the pair‐members of respondents with each other. Pediatr Blood Cancer 2008;50:838–843. © 2007 Wiley‐Liss, Inc.
The ins and outs of lipid domain proteomics
Authors: Sprenger Richard R. , Horrevoets Anton J. G. 
Published: July 2007

AbstractLipid domains, also known as lipid rafts, are segregated from the bulk of the plasma membrane and have been attributed a multitude of important cellular functions in both health and disease. The large number of recent proteomic studies of their composition has produced a stunning list of potential constituents, leading to many contradictory conclusions. The actual methodology used in the different studies therefore seems to be of pivotal importance with regard to the derived lipid domain proteomes. In this review, we attempt to interpret recent findings in light of the methodology used and identify potential artifacts. This integrative view tries to tentatively define the core composition, the associated functions, the topology, as well as the dynamics of lipid domain proteomes. In other words: who's in and who's out.
Preparation of carboxyl‐end‐group polyacrylamide with low polydispersity by ATRP initiated with chloroacetic acid
Authors: Jiang Jianguo , Lu Xiaoyan , Lu Yun 
Published: July 2007

AbstractAtom transfer radical polymerization (ATRP) of acrylamide was successfully carried out with chloroacetic acid as initiator and CuCl/N,N,N′,N′‐tetramethylethylenediamine (TMEDA) as catalyst either in water at 80 °C or in glycerol–water (1:1 v/v) medium at 130 °C. In both cases, carboxyl‐end‐group polyacrylamide was obtained with lower polydispersity ranging from 1.03 to 1.44 depending on the polymerization condition. Polymerization kinetics showed that the polymerizations proceeded with a living/controlled nature and accelerated at a higher temperature. The effect of pH in the reaction system on the polymerizations was further studied, revealing that chloroacetic acid not only served as a functional initiator for the ATRP of acrylamde but also provided the acidic polymerization condition, which effectively protected the ATRP of acrylamide from the unexpected complexation and cyclization side‐reactions. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 3956–3965, 2007
Novel use of mesoporous aluminas as supports for Cp2ZrCl2 and Cp*ZrMe3: Ethylene polymerization and formation of polyethylene nanofibers
Authors: Turunen Jani P. J. , Venäläinen Tapani , Suvanto Sari , Pakkanen Tuula T. 
Published: July 2007

AbstractMesoporous aluminas with average pore sizes of 4.3–7.8 nm were prepared by anodization of an aluminum film (AAO), and by a sol–gel templating method (TPL). In addition to a commercial alumina and sulfated TPL, the aluminas were used as supports for cyclopentadienyl zirconocene dichloride (Cp2ZrCl2) and trimethyl(η5‐pentamethylcyclopentadienyl)zirconium (Cp*ZrMe3) and tested in the polymerization of ethylene. The metallocenes supported on the alumina prepared with the templating method and its sulfated modification exhibited polymerization activities of 440 and 350 kgPE/(molZr × h × bar), respectively, comparable to that obtained with silica‐supported metallocenes (390 kgPE/(molZr × h × bar)). The acid site distribution of the aluminas was studied with FTIR and temperature programmed desorption (TPD) of pyridine, and also the amount of medium and strong acid sites was determined gravimetrically from the adsorption of pyridine. Relative to the surface area, AAO with the highest amount of acid sites (2.10 μmolpy/m) adsorbed Cp2ZrCl2 and Cp*ZrMe3 the most. Study of the polymers' morphology with a scanning electron microscope revealed polyethylene nanofibers in all the polymer samples, also in those obtained from the reference polymerizations with homogeneous Cp2ZrCl2 and Cp*ZrMe3. This finding suggests that a catalyst support with a tubular pore structure is not a prerequisite for the formation of polymer nanofibers. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 4002–4012, 2007
Synthesis of graft copolymers with “V‐shaped” and “Y‐shaped” side chains via controlled radical and anionic polymerizations
Authors: Yu Fengping , He Junpo , Wang Xiaojun , Gao Guangzheng , Yang Yuliang 
Published: July 2007

AbstractA combination of nitroxide‐mediated radical polymerization and living anionic polymerization was used to synthesize a series of well‐defined graft (co)polymers with “V‐shaped” and “Y‐shaped” branches. The polymer main chain is a copolymer of styrene and p‐chloromethylstyrene (PS‐co‐PCMS) prepared via nitroxide‐mediated radical polymerization. The V‐shaped branches were prepared through coupling reaction of polystyrene macromonomer, carrying 1,1‐diphenylethylene terminus, with polystyryllithium or polyisoprenyllithium. The Y‐shaped branches were prepared throughfurther polymerization initiated by the V‐shaped anions. The obtained branches, carrying a living anion at the middle (V‐shaped) or at the end of the third segment (Y‐shaped), were coupled in situ with pendent benzyl chloride of PS‐co‐PCMS to form the target graft (co)polymers. The purified graft (co)polymers were analyzed by size exclusion chromatography equipped with a multiangle light scattering detector and a viscometer. The result shows that the viscosities and radii of gyration of the branched polymers are remarkably smaller than those of linear polystyrene. In addition, V‐shaped product adopts a more compact conformation in dilute solution than the Y‐shaped analogy. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 4013–4025, 2007
Characterization of the chemical composition of a block copolymer by liquid chromatography/mass spectrometry using atmospheric pressure chemical ionization and electrospray ionization
Authors: van Leeuwen Suze M. , Tan BoonHua , Grijpma Dirk W. , Feijen Jan , Karst Uwe 
Published: July 2007

AbstractLiquid chromatography/mass spectrometry (LC/MS) with electrospray ionization (ESI) and atmospheric pressure chemical ionization (APCI) in the positive and negative ion modes was used for the characterization of a block copolymer consisting of methoxy poly(ethylene oxide) (mPEO), an ε‐caprolactone (CL) segment and linoleic acid (LA), used as surfactant in water‐based latex paints. Chromatographic separation was obtained based on the number of CL units in the polymer species and the presence of an mPEO and/or LA tail. Different ionization methods were found to be complementary and only their combination allowed the qualitative profiling of the chemical composition. The LC/MS method has proven valuable for following the reaction in time, as well as for comparison of different polymeric surfactants. Copyright © 2007 John Wiley & Sons, Ltd.
Rapid white truffle headspace analysis by proton transfer reaction mass spectrometry and comparison with solid‐phase microextraction coupled with gas chromatography/mass spectrometry
Authors: Aprea Eugenio , Biasioli Franco , Carlin Silvia , Versini Giuseppe , Märk Tilmann D. , Gasperi Flavia 
Published: July 2007

AbstractThe gastronomic relevance and high price of white truffle are related mainly to its unique aroma. Here we evaluate, for the first time, the possibility of characterizing in a rapid and non‐destructive way the aroma of white truffles based on proton transfer reaction mass spectrometry (PTR‐MS). We indicate that anonymous PTR‐MS fingerprinting allows sample classification and we also compare qualitatively and quantitatively PTR‐MS data with measurements made by solid‐phase microextraction gas chromatography (SPME‐GC) of the same samples under the same conditions. PTR‐MS fragmentation data of truffle‐relevant compounds are also published here for the first time. Most of the sulfur‐containing compounds detected by GC and relevant for white truffle aroma have a high positive correlation with single PTR‐MS peaks. Our work indicates that, after preliminary comparison with GC data, PTR‐MS is a new tool for the rapid, quantitative and non‐invasive characterization of white truffle by direct headspace injection without any pre‐concentration. Copyright © 2007 John Wiley & Sons, Ltd.
‘LC‐electrolyte effects’ improve the bioanalytical performance of liquid chromatography/tandem mass spectrometric assays in supporting pharmacokinetic study for drug discovery
Authors: Wang Li , Sun Yan , Du Feifei , Niu Wei , Lu Tong , Kan Jingmin , Xu Fang , Yuan Kaihong , Qin Tao , Liu Changxiao , Li Chuan 
Published: July 2007

AbstractThe development of rapid and sensitive bioanalytical methods in a short time frame with acceptable levels of precision and accuracy is imperative for successful drug discovery. We previously reported that the use of a mobile phase containing an extremely low concentration of ammonium formate or formic acid increased analyte electrospray ionization (ESI) response and controlled against matrix effects. We designated these favorable effects ‘LC‐electrolyte effects’. In order to support rapid pharmacokinetic (PK) studies for drug discovery, we applied LC‐electrolyte effects to the development of generic procedures that can be used to quickly generate reliable PK data for compound candidates. We herein demonstrate our approach using four model tested compounds (Compd‐A, ‐B, ‐C, and ‐D). The analytical methods involve generic protein precipitation for sample clean‐up, followed by application of fast liquid chromatographic (LC) gradients and the subsequent use of electrospray ionization tandem mass spectrometry (ESI‐MS/MS) for individual measurement of the tested compounds in 20‐µL plasma samples. Good linearity over the concentration range of 1.6 or 8–25000 ng/mL (r2 > 0.99), precision (RSD, 0.45–13.1%), and accuracy (91–112%) were achieved through the use of a low dose of formic acid (0.4 mM or 0.015‰) in the methanol/water‐based LC mobile phase. The analytical method was quite sensitive, providing a lower limit of quantification of 1.6 pg on‐column except for Compd‐C (8 pg), and showed negligible ion suppression caused by matrix components. Finally, the assay suitability was demonstrated in simulated discovery PK studies of the tested compounds with i.v./p.o. dosing of rats. This new assay approach has been adopted with good results in our laboratory for many recent discovery PK studies. Copyright © 2007 John Wiley & Sons, Ltd.
Development and application of stable carbon isotope analysis to the detection of cortisol administration in cattle
Authors: Bichon E. , Kieken F. , Cesbron N. , Monteau F. , Prévost S. , André F. , Le Bizec B. 
Published: July 2007

AbstractThe use of anabolic agents in food‐producing animals has been prohibited within the EU since 1988. The control of the illegal use of natural steroid hormones in cattle is still an exciting analytical challenge as no definitive method and nonambiguous analytical criteria are available. We have used gas chromatography/combustion/isotope ratio mass spectrometry (GC/C/IRMS) to demonstrate the administration of cortisol to cattle. The method consisted of an efficient combination between OASIS HLB solid‐phase extraction (SPE), oxidation, SiOH SPE and semi‐preparative high‐performance liquid chromatography (HPLC) for glucocorticoid purification. By comparison of the 13C/12C isotopic ratio of the oxidised product of cortisol, i.e. 5β‐androstane‐3,11,17‐trione (5βAAT), with an endogenous reference compound (ERC), dehydroepiandrosterone (DHEA), the differentiation of cortisol metabolite origin, either endogenous or exogenous, has been achieved. After treatment of an animal, the δ13CVPDB values of 5βAAT reached −30 to −32‰, whereas the δ13CVPDB values of DHEA remained at −25‰. A significant difference in the δ13CVPDB values between DHEA and 5βAAT was measurable over a period of 3 days after a single administration of cortisol to the animal. Copyright © 2007 John Wiley & Sons, Ltd.
Clustering of polycyclic aromatic hydrocarbons in matrix‐assisted laser desorption/ionization and laser desorption mass spectrometry
Authors: Cristadoro Anna , Räder Hans Joachim , Müllen Klaus 
Published: July 2007

AbstractThe desorption/ionization behaviour of polycyclic aromatic hydrocarbons (PAHs) in matrix‐assisted laser desorption/ionization (MALDI) and laser desorption (LD) mass spectrometry was studied by the solvent‐free sample preparation method. As the understanding of the desorption/ionization mechanism in MALDI is normally hampered by the different ionization and desorption efficiencies of the analytes, this work was focused on the analyses of a homologous series of four hexabenzocoronenes (HBCs) possessing virtually the same ionization efficiency: HBC parent, hexamethyl‐hexabenzocoronene (HBC‐C1), hexapropyl‐hexabenzocoronene (HBC‐C3) and hexakis(dodecyl)‐hexabenzocoronene (HBC‐C12). The different signal intensities obtained in their mass spectra can be related to differences in their desorption efficiencies, which are attributed to the different strengths of the intermolecular interactions between unsubstituted and alkylated HBCs in the solid state. The influence of the aromatic structure of PAHs on their photoionization/desorption probability was investigated. As a model system, an equimolar mixture composed of HBC‐C12 and hexakis(dodecyl)‐hexaphenylbenzene (HPB‐C12) was chosen. The aromatic structures of both molecules and thus their absorption coefficients at the laser wavelength differ substantially and have a huge influence on their photoionization efficiency. The combined effect of laser light absorption and intermolecular interactions on the desorption/ionization behaviour of giant PAHs was further studied by using an equimolar mixture composed of a larger PAH (C222H42) and its dendritic precursor (C222H150). This mixture shows the opposite behaviour to that of the former example, because the balance between desorption and ionization efficiency has changed significantly. The present investigation should be of interest for providing a better understanding of MALDI and LD spectra obtained from natural PAH‐containing samples, such as heavy oils, asphaltenes or pitches, for which our artificial mixtures represent suitable model systems. Copyright © 2007 John Wiley & Sons, Ltd.
Electrospray tandem mass spectroscopic characterisation of 18 antiretroviral drugs and simultaneous quantification of 12 antiretrovirals in plasma
Authors: Gehrig Anne‐Kathrin , Mikus Gerd , Haefeli Walter E. , Burhenne Jürgen 
Published: July 2007

AbstractThe determination of antiretroviral drug concentrations in patients treated with highly active antiretroviral therapy (HAART) is an essential part of optimum patient management because of the multitude of pharmacokinetic drug interactions between these drugs and the risk of treatment failure or viral resistance if therapeutic concentrations are not reached. Currently, 21 different antiretrovirals are used in various combinations rendering therapeutic drug monitoring a laborious task. We therefore aimed to simultaneously determine as many antiretrovirals as possible using triple quadrupole mass spectroscopy with electrospray ionisation. For this purpose, spectra and fragmentation patterns of the protease inhibitors amprenavir, atazanavir, indinavir, lopinavir, nelfinavir, ritonavir, and saquinavir, the non‐nucleoside reverse transcriptase inhibitors delavirdine, efavirenz, and nevirapine, the nucleoside reverse transcription inhibitors abacavir, didanosine, emtricitabine, lamivudine, stavudine, zalcitabine, and zidovudine, and the nucleotide reverse transcriptase inhibitor tenofovir were evaluated. A bioanalytical method to determine all protease and non‐nucleoside reverse transcriptase inhibitors, and zalcitabine and zidovudine concentrations in biological matrices was developed. Samples were prepared by protein precipitation with methanol after addition of three different internal standards. Antiretrovirals were separated by high‐performance liquid chromatography on a Nucleosil C18‐100 Nautilus column using a gradient of 20 mM ammonium acetate including 0.1% aqueous acetic acid and acetonitrile and detected by electrospray ionisation/tandem mass spectrometry in the negative (efavirenz, stavudine, zidovudine) or positive ionisation mode (all other compounds). The bioanalytical method was successfully validated according to FDA guidelines and applied to plasma and cerebrospinal fluid samples of patients treated for acquired immunodeficiency syndrome (AIDS). Copyright © 2007 John Wiley & Sons, Ltd.
Development of a tabletop time‐of‐flight mass spectrometer with an ion attachment ionization technique
Authors: Saito Naoaki , Nanjyo Jyun‐ichi , Taneda Yasuyuki , Shiokawa Yoshiro , Tanimoto Mitsumori 
Published: July 2007

AbstractWe report a new type of mass spectrometry based on a time‐of‐flight mass spectrometer combined with an ion attachment ionization technique (IA‐TOF). In contrast to electron ionization mass spectra, IA‐TOF mass spectra are not complicated by peaks due to fragmentation of the molecular ion; the adduct ion formed in IA does not fragment. We developed a tabletop IA‐TOF system and evaluated its performance by analyzing specimens originally in the gas, liquid, and solid phases. We obtained fragment‐free spectra covering a mass range up to m/z 3400 with a mass resolution of about 4700. Our IA‐TOF system realizes accurate and versatile real‐time mass spectrometry. Copyright © 2007 John Wiley & Sons, Ltd.
Women of Color teaching students of Color: Creating an effective classroom climate through caring, challenging, and consulting
Authors: Saavedra Dora E. , Saavedra Marisa L. 
Published: July 2007

AbstractBeing a Hispanic female faculty member in South Texas can be a challenge. This chapter discusses three pedagogical tools (caring, challenging, and consulting) that we use to create a classroom climate that enhances Hispanic students' success by engaging and motivating them to succeed in one of the poorest areas of the country.
High pressure liquid chromatography for the analysis of soluble carbohydrates in defatted oilseed flours
Authors: Cegla G. F. , Bell K. R. 
Published: July 2007

AbstractThe soluble carbohydrate content of four defatted oilseed flours (cottonseed, soybean, peanut, and sun‐flower) was determined by using high pressure liquid chromatography. The best method of separating the sugars from the other components of water extracted flour was found to be thin layer chromatography. Plates of Silica Gel H with a running solvent of iso‐propanol‐water‐ehtyl acetate (54:26:20) gave good isolation of the sugars. The μ BONDAPAK/ Carbohydrate column was used to analyze the sugars. An eluting solvent of acetonitrile and water (75:25 and 72:28) at a flow rate of 1.5 ml/min gave the best resolution of the carbohydrates. The major carbohy‐drates in the oilseed flours were glucose, sucrose, raffinose, and stachyose. Small amounts of trehalose and an unidentified disaccharide were found in the flour of sunflower.
Chlorinated pesticide residues in meat and fat from animals raised in iran
Authors: Hashemy‐Tonkabony S. E. , Afshar A. , Ghazisaidi K. , Assadi‐Langaroodi F. , Messchi M. , Ahmadi Z. 
Published: July 2007

AbstractMeat and fat samples (310) from carcasses of cattle, sheep, goats and camels from different regions of Iran were analyzed to determine concentrations of chlorinated pesticide residues. DDT, DDE, TDE, lindane, dieldrin and endrin were detected in the adipose tissues and meat of all species. Incidence as well as concentration of most pesticide residues were lowest in the camel and highest in the sheep. External fat samples were satisfactory for pesticide monitoring. The concentration of DDT did not exceed the World Health Organization (WHO) maximum limit for meat and fat.