bluuebunny/crossref_metadata_2025_split huggingface dataset:
Capillary zone electrophoresis (CZE) coupled to time‐of‐flight mass spectrometry (TOF‐MS) applied to the analysis of illicit and controlled drugs in blood
Authors: Gottardo Rossella , Polettini Aldo , Sorio Daniela , Pascali Jennifer Paola , Bortolotti Federica , Liotta Eloisa , Tagliaro Franco 
Published: October 2008

AbstractA new method for the determination of illicit and abused drugs in blood by capillary zone electrophoresis–electrospray ionization–time‐of‐flight mass spectrometry is proposed, in view of its application in clinical and forensic toxicology. The analytes (methamphetamine, methylenedioxyamphetamine, methylenedioxyethylamphetamine, methylenedioxymethamphetamine, methadone, cocaine, morphine, codeine, 6‐acethylmorphine, benzoylecgonine) were separated with capillary zone electrophoresis by applying 15 kV within 25 min, in an uncoated fused‐silica capillary (75 μm × 100 cm) using a 25 mM ammonium formate electrolyte solution (pH 9.5). The capillary electropherograph was coupled to time‐of‐flight mass spectrometry through an orthogonal electrospray ionization source, with a coaxial sheath liquid interface. The sheath liquid was composed of isopropanol‐water (1:1 v/v) containing 0.5% formic acid delivered at 4 μL/min. Forensic drugs were identified by exact mass determination (mass accuracy typically ≤5 ppm) and by matching of the isotopic pattern.Under optimized conditions, linearity was assessed in the range 10–2000 ng/mL, with correlation coefficients between 0.9744 and 0.9982 for all the analytes. LODs were in the range of 2–10 ng/mL (S/N ≥3) and LOQs of 10–30 ng/mL. The CVs (tested at 40 and 800 ng/mL in biological matrix) were below 2.97% for migration times and below 14.61% for peak area ratios (analyte/internal standard). Blood samples were extracted by using a liquid–liquid extraction procedure and injected under field‐amplified sample stacking conditions. The method was successfully applied to real cases.
The role of cysteine and cysteine–S conjugates as odour precursors in the flavour and fragrance industry
Authors: Starkenmann Christian , Troccaz Myriam , Howell Kate 
Published: October 2008

AbstractVolatile sulphur compounds are important odorants in the flavour and fragrance industries. Recent developments in the field have reinvigorated sulphur compound research, particularly with regard to the precursor compounds of volatile thiols. The present review concentrates on the role of cysteine and cysteine–S conjugates as precursor compounds for a variety of aromas and examines the chemical and enzymatic pathways of degradation and biotransformation. Cysteine is an important source of sulphur in flavour chemistry and may be degraded into hydrogen sulphide, which can further participate in other reactions. Direct reactions of cysteine and the pathways particular to various flavours and fragrances are discussed, with an emphasis on the precursor compounds cysteine–S conjugates. The importance of cysteine precursors in plants, including onion, wine, passion fruit, bitter orange, asparagus and bell pepper and the formation of natural scents in cats and humans are discussed. Copyright © 2008 John Wiley & Sons, Ltd.
Forgetting the learning curve for a moment: how much performance is unrelated to own experience?
Authors: Huesch Marco D. , Sakakibara Mariko 
Published: October 2008

AbstractVolume–outcome relationships are of clear importance for most participants in the health‐care industry; research and appropriate policy implications are of critical importance. In this letter we critique the prevailing ‘learning‐by‐doing’ view in cardiac surgery. We illustrate the very wide disparity in empirical findings on volume–outcome relationships there, in the context of broader open issues in ‘learning curves’ in general. Potential complementary mechanisms, e.g. ‘social learning by knowledge spillovers’ are introduced; these cast into doubt the prevailing policy recommendations of simple regionalization and volume smoothing. Copyright © 2008 John Wiley & Sons, Ltd.
First‐year quality of life assessment of an intra‐arterial (RADPLAT) versus intravenous chemoradiation phase III trial
Authors: Ackerstaff Annemieke H. , Balm Alfons J. M. , Rasch Coen R. N. , de Boer Jan Paul , Wiggenraad Ruud , Rietveld Derk H. F. , Gregor R. Theo , Kröger Robert , Hilgers Frans J. M. 
Published: October 2008

AbstractBackground.We report the results of a multicenter randomized phase III study, assessing quality of life (QOL) in intra‐arterial (IA) versus standard intravenous (IV) chemoradiation in advanced head and neck cancer.Methods.Two hundred seven patients with inoperable stage IV disease—152 men and 55 women; mean age, 55 years—were included in this study. The patients were treated with standard radiotherapy with 4 weekly IA or 3 weekly IV cisplatin infusions. The QOL assessments carried out were EORTC‐C30, H&N35, and trial‐specific questionnaires.Results.Overall QOL deteriorated in all patients during treatment, is gradually improving over 1 year. IA patients showed significantly less nausea and vomiting at week 7 (p <.001). IV patients were significantly more fatigued (p <.006). At 1 year, no significant difference in tube feeding was found. Voice quality slightly exceeded the pretreatment values at 1 year. Forty‐two of 62 employed patients returned to work.Conclusion.During treatment, significantly fewer problems with nausea and vomiting occurred in IA than in IV patients. Both groups showed improved voicing and oral intake during follow‐up, often exceeding pretreatment values at 1 year. © 2008 Wiley Periodicals, Inc. Head Neck, 2009
Validation of the EORTC QLQ‐C30 and EORTC QLQ‐H&N35 in patients with laryngeal cancer after surgery
Authors: Singer Susanne , Wollbrück Dorit , Wulke Cornelia , Dietz Andreas , Klemm Eckart , Oeken Jens , Meister Eberhard F. , Gudziol Hilmar , Bindewald Julian , Schwarz Reinhold 
Published: October 2008

AbstractBackground.The aim of this study was to test the validity of the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire, Core Module (QLQ‐C30) and Head and Neck Module (QLQ‐H&N35) for patients who have undergone surgery due to laryngeal cancer.Methods.A total of 323 patients from 6 different centers in Germany who had been operated on completed the QLQ‐C30 and the QLQ‐H&N35 in addition to being surveyed in a personal interview.Results.Multitrait scaling analysis confirmed the proposed scale structure of both questionnaires. Cronbach's alpha of the QLQ‐C30 scales ranged from 0.64 (Cognitive Functioning) to 0.94 (Global Health Status); the alpha of the QLQ‐H&N35 ranged from 0.55 (Speech) to 0.90 (Sexuality). Known‐groups comparisons showed multiple differences in sociodemographic and clinical variables.Conclusion.It can be concluded that the QLQ‐H&N35, in conjunction with the QLQ‐C30, is a reliable instrument that is able to differentiate between diverse groups of patients with laryngeal cancer after surgery. © 2008 Wiley Periodicals, Inc. Head Neck, 2009
Diphenyl diselenide protects against hematological and immunological alterations induced by mercury in mice
Authors: Brandão Ricardo , Borges Lysandro Pinto , Oliveira Renata de , Rocha João B. T. , Nogueira Cristina W. 
Published: October 2008

AbstractMercury is a heavy metal that can cause a variety of toxic effects on the organism, such as hematological and immunological alterations. In the present investigation, deleterious effects of mercury‐intoxication in mice and a possible protective effect of diphenyl diselenide (PhSe)2 were studied. Male adult Swiss albino mice received daily a pretreatment with (PhSe)2 (15.6 mg/kg, orally) for 1 week. After this week, mice received daily mercuric chloride (1 mg/kg, subcutaneously) for 2 weeks. A number of hematological (erythrocytes, leukocytes, platelets, hemoglobin, hematocrit, reticulocytes, and leukocytes differential) and immunological (immunoglobulin G and M plasma concentration) parameters were evaluated. Another biomarker of tissue damage, lactate dehydrogenase (LDH), was also determined. The results demonstrated that mercury exposure caused a reduction in the erythrocyte, hematocrit, hemoglobin, leukocyte, and platelet counts and an increase in the reticulocyte percentages. (PhSe)2 was effective in protecting against the reduction in hematocrit, hemoglobin, and leukocyte levels. (PhSe)2 ameliorated reticulocyte percentages increased by mercury. However, (PhSe)2 was partially effective in preventing against the decrease in erythrocyte and platelet counts. Immunoglobulin G and M concentrations and LDH activity were increased by mercury exposure, and (PhSe)2 was effective in protecting against these effects. In conclusion, (PhSe)2 was effective in protecting against hematological and immunological alterations induced by mercury in mice. © 2008 Wiley Periodicals, Inc. J Biochem Mol Toxicol 22:311–319, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/jbt.20242
Proteomic analysis of Latrodectus tredecimguttatus venom for uncovering potential latrodectism‐related proteins
Authors: Duan Zhigui , Yan Xiaojun , Cao Rui , Liu Zhen , Wang Xianchun , Liang Songping 
Published: October 2008

AbstractBlack widow spider is one of the most poisonous spiders in the world. Up to now, there have been few systematic analyses of the spider venom components, and the mechanism of action of the venom has not been completely understood. In this work, we employed combinative proteomic strategy to analyze the venom collected from living adult spider Latrodectus tredecimguttatus by electrical stimulation. The experiments demonstrated that the venom is primarily composed of high molecular weight proteins and has high abundance proteins around 100 kDa. The content of peptides and proteins with low molecular weight is low. A total of 75 nonredundant venom proteins with distinct function were unambiguously identified. Besides the known black widow spider venom proteins including latrotoxins, a variety of hydrolases and other proteins with special activity were found in the venom, such as proteinase, phospholipase, phosphatase, nuclease, fucolectin, venom allergen antigen 5‐like protein and trypsin inhibitor, and so on. Their possible biological actions and relationship with latrodectism were discussed. The results help to understand the complexity and action mechanism of L. tredecimguttatus venom. © 2008 Wiley Periodicals, Inc. J Biochem Mol Toxicol 22:328–336, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/jbt.20244
Biochemical effects of gestational coexposure to lead and cadmium on reproductive performance, placenta, and ovary
Authors: Nampoothiri Laxmipriya P. , Gupta Sarita 
Published: October 2008

AbstractAdult virgin 4‐day cycling synchronized Charles foster females were treated subcutaneously (0.05 mg/kg body wt/day) with sodium acetate (control), lead acetate or cadmium acetate alone, or both during gestational period, with pretreatment of 5 days prior to mating. There were no alterations in reproductive performance in all metal‐treated groups. Implantation enzymes, cathepsin‐D and alkaline phosphatase, activity were altered, but no change in the reproductive performance was observed. The key steroidogenic enzymes of ovary and placenta (3β‐HSD and 17β‐HSD), along with gonadal steroids, were affected the most in cadmium and combined treated animals whereas lead‐treated animals showed a minimum change compared to the control group. Maximum displacement of zinc bound to metallothionein was more in cadmium and combined treated rats when compared to other metal‐treated groups. Biomolecules such as glycogen, protein, RNA, DNA, and protein content were affected in all metal‐treated groups, whereas cadmium‐treated animals showed greater effect. General parameters of toxicity such as alkaline phosphatase, serum glutamate pyruvate transaminase, and creatinine were altered but were within the normal range. Biochemical effects are correlated with metals accumulated in blood, reproductive tissue such as placenta and ovary. © 2008 Wiley Periodicals, Inc. J Biochem Mol Toxicol 22:337–344, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/jbt.20246
Effect of copper intoxication on rat liver proteasome activity: Relationship with oxidative stress
Authors: Alexandrova Albena , Petrov Lubomir , Georgieva Almira , Kessiova Mila , Tzvetanova Elina , Kirkova Margarita , Kukan Marian 
Published: October 2008

AbstractCopper toxicity is associated with formation of reactive oxygen species, which are capable to oxidize proteins. The selective removal of the latter by the 20S proteasome is considered an essential part of the cell antioxidant defense system. The aim of the present study was to investigate whether peptidase activities of rat liver proteasomes were affected by chronic (40 mg CuSO4/rat/daily with the drinking water for 2 weeks) and acute (20 mg/kg CuSO4, s.c.) copper treatment. To evaluate the role of proteasome, its inhibitor MG132 was also used. The degree of copper‐induced oxidative stress (OS), established by measuring lipid peroxidation, protein oxidation, and cellular glutathione level, as well as activities of antioxidant enzymes—catalase, superoxide dismutase, and gultathionine peroxidase, depended on the mode of copper administration. Chronic copper administration (mild oxidative stress) did not affect proteasome activities, whereas acute copper treatment (severe oxidative stress) caused a decline in chymotryptic‐ and tryptic‐like activities. The treatment of copper‐loaded animals with MG132 did not change copper‐induced alterations in the tested indices, except an additional increase in protein oxidation and inhibition of glutathionine peroxidase activity. The results suggested that the in vivo copper‐induced oxidative stress was associated with changes in the catalytic activity of proteasome. © 2008 Wiley Periodicals, Inc. J Biochem Mol Toxicol 22:354–362, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/jbt.20248
Atrazine‐induced alterations in rat erythrocyte membranes: Ameliorating effect of vitamin E
Authors: Singh Mohan , Sandhir Rajat , Kiran Ravi 
Published: October 2008

AbstractErythrocytes are a convenient model to understand oxidative damage to the membranes induced by various xenobiotics. The objective of the present study was to investigate the propensity of atrazine to induce oxidative stress and its possible attenuation by vitamin E. Experimental animals were orally administered atrazine (300 mg kg−1 body weight, daily) and vitamin E (100 mg kg−1 body weight, daily) for a period of 7, 14, and 21 days. Erythrocyte membranes were prepared and analyzed for acetylcholinesterase (AChE) activity, lipid peroxidation (LPO), and lipid composition. Susceptibility of erythrocytes to atrazine exposure was further investigated in terms of morphological alterations by scanning electron microscopy (SEM). Results indicate that atrazine exposure caused a significant inhibition of AChE activity and induction of oxidative stress in terms of increased malondialdehyde (MDA) levels. Atrazine treatment significantly decreased total lipid, cholesterol, and phospholipid content of erythrocyte membranes. SEM revealed varying degrees of distortion depending on duration of atrazine exposure. However, administration of vitamin E ameliorated the oxidative stress and changes in the erythrocyte membranes induced by atrazine. © 2008 Wiley Periodicals, Inc. J Biochem Mol Toxicol 22:363–369, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/jbt.20249
Synthesis of 2‐(5Z,8Z,11Z,14Z)‐Icosa‐5,8,11,14‐tetraenamidoethyl‐d4 dihydrogen phosphate, tetra‐deuterated pAEA
Authors: Cheng Kejun , Saha Bijali , Mahadevan A. , Razdan Raj K. , Kunos George , Jacobson Arthur E. , Rice Kenner C. 
Published: October 2008

AbstractA labile intermediate phospho‐anandamide (2‐(5Z,8Z,11Z,14Z)‐icosa‐5,8,11,14‐tetraenamidoethyl dihydrogen phosphate, pAEA) has been identified in mouse brain and macrophages, but its precise quantitation was difficult because of its low concentration and chemical instability. We report the synthesis of tetra‐deuterated pAEA from 2‐aminoethyl dihydrogen phosphate‐1,1,2,2‐d4 and (5Z,8Z,11Z,14Z)‐2,5‐dioxopyrrolidin‐1‐yl icosa‐5,8,11,14‐tetraenoate. The compound will be used to quantitate the pAEA necessary for a novel biosynthetic pathway. Published in 2008 by John Wiley & Sons, Ltd.
Inflow quantification in three‐dimensional cardiovascular MR imaging
Authors: Nezafat Reza , Herzka Daniel , Stehning Christian , Peters Dana C. , Nehrke Kay , Manning Warren J. 
Published: October 2008

AbstractPurposeTo investigate blood inflow enhancement (or lack thereof) in three‐dimensional (3D) cardiovascular MR for both single phase whole‐heart and cine biventricular functions.Materials and MethodsA 3D imaging sequence is proposed in which radiofrequency excitation gradient is changed without modifying image acquisition or phase/slice encoding. This imaging sequence enables direct inflow measurement while retaining static voxel signal‐to‐noise ratio. Inflow measurements were performed for both spoiled gradient‐echo (GRE) imaging and balanced steady‐state free precession (SSFP) in 18 healthy subjects.ResultsFor single phase imaging, increasing slab thickness from 3 to 10 cm lead to 73% and 59% reductions in contrast‐to‐noise ratio (CNR) with GRE and SSFP, respectively. For cine acquisitions, systolic CNR was reduced by 85% and 50% for the GRE and SSFP acquisitions, respectively, while diastolic CNR was reduced by 64% and 42%.ConclusionThere is significant loss of CNR between blood and myocardium when using larger 3D slabs due to saturation of inflowing spins. The loss of contrast is less pronounced for SSFP than for GRE, though both acquisition techniques suffer. J. Magn. Reson. Imaging 2008;28:1273–1279. © 2008 Wiley‐Liss, Inc.
Flow in porous metallic materials: A magnetic resonance imaging study
Authors: Xu Shoujun , Harel Elad , Michalak David J. , Crawford Charles W. , Budker Dmitry , Pines Alexander 
Published: October 2008

AbstractPurposeTo visualize flow dynamics of analytes inside porous metallic materials with laser‐detected magnetic resonance imaging (MRI).Materials and MethodsWe examine the flow of nuclear‐polarized water in a porous stainless steel cylinder. Laser‐detected MRI utilizes a sensitive optical atomic magnetometer as the detector. Imaging was performed in a remote‐detection mode: the encoding was conducted in the Earth's magnetic field, and detection is conducted downstream of the encoding location. Conventional MRI (7T) was also performed for comparison.ResultsLaser‐detected MRI clearly showed MR images of water flowing through the sample, whereas conventional MRI provided no image.ConclusionWe demonstrated the viability of laser‐detected MRI at low‐field for studying porous metallic materials, extending MRI techniques to a new group of systems that is normally not accessible to conventional MRI. J. Magn. Reson. Imaging 2008;28:1299–1302. © 2008 Wiley‐Liss, Inc.
k‐t‐space accelerated myocardial perfusion
Authors: Jung Bernd , Honal Matthias , Hennig Jürgen , Markl Michael 
Published: October 2008

AbstractPurposeTo investigate the performance of the recently introduced spatiotemporal parallel imaging technique called parallel MRI with extended and averaged generalized autocalibrating partially parallel acquisitions (GRAPPA) kernels (PEAK‐GRAPPA) for myocardial perfusion measurements.Materials and MethodsA study with 11 patients with myocardial infarction was performed to compare nonaccelerated perfusion imaging, i.e., fully acquired k‐space data, with the results of conventional GRAPPA and PEAK‐GRAPPA with a net acceleration factor of 2.4 to 3.4. Signal time courses reflecting the passage of the contrast agent bolus in different regions of the heart were evaluated for these different reconstruction methods.ResultsReconstruction with PEAK‐GRAPPA demonstrated considerably improved image quality compared to conventional GRAPPA. In addition, signal time courses for PEAK‐GRAPPA demonstrated an excellent agreement compared to full k‐space data, which is necessary for an accurate qualitative and quantitative assessment of myocardial perfusion.ConclusionQualitative and quantitative results of patient measurements illustrate that the temporal fidelity of nonperiodic processes such as myocardial perfusion are preserved with PEAK‐GRAPPA up to net acceleration factors of more than 3 while showing a superior image quality compared to conventional GRAPPA and a sliding‐window reconstruction. J. Magn. Reson. Imaging 2008;28:1080–1085. © 2008 Wiley‐Liss, Inc.
Pulmonary artery size and function after Fontan operation at a young age
Authors: Robbers‐Visser Daniëlle , Helderman Frank , Strengers Jan L. , van Osch‐Gevers Lennie , Kapusta Livia , Pattynama Peter M. , Bogers Ad J. , Krams Rob , Helbing Willem A. 
Published: October 2008

AbstractPurposeTo assess pulmonary artery (PA) size, flow variables, and wall shear stress (WSS) in patients after Fontan operation at a young age.Materials and MethodsFlow in the branch PA was obtained with phase contrast velocity‐encoded cardiovascular magnetic resonance imaging in 14 patients before and after low‐dose dobutamine stress (7.5 μg/kg/min) and in 17 healthy controls at rest.ResultsAt rest, stroke index, total flow, average, and peak flow rate were all statistically significantly lower in patients than in controls (P < 0.001). With stress‐testing, all variables increased in patients (P < 0.001), apart from stroke index, which did not change. At rest, branch PA area did not differ between patients and controls. Distensibility was lower in patients than in controls (P < 0.001). With stress‐testing, area and distensibility did not change. At rest, WSS was lower in patients than in controls (P < 0.001). WSS increased with stress‐testing (P < 0.001), but not to the same levels as during resting conditions of the control group.ConclusionPA size is normal long‐term after Fontan operation at a young age. Flow variables, distensibility, and WSS are significantly lower compared to healthy controls, and do not show adequate reactions with stress‐testing, which is suggestive of pulmonary artery endothelial and/or vascular dysfunction. J. Magn. Reson. Imaging 2008;28:1101–1107. © 2008 Wiley‐Liss, Inc.
Consideration of physiological response in numerical models of temperature during MRI of the human head
Authors: Wang Zhangwei , Lin James C. , Vaughan J. Thomas , Collins Christopher M. 
Published: October 2008

AbstractPurposeTo examine the thermal effects of the physiological response to heating during exposure to radiofrequency (RF) electromagnetic fields in magnetic resonance imaging (MRI) with a head‐specific volume coil.Materials and MethodsNumerical methods were used to calculate the temperature elevation in MRI of the human head within volume coils from 64–400 MHz at different power levels both with and without consideration of temperature‐induced changes in rates of metabolism, perspiration, radiation, and perfusion.ResultsAt the highest power levels currently allowed in MRI for head volume coils, there is little effect from the physiological response as predicted with existing methods. This study does not rule out the possibility that at higher power levels or in different types of coils (such as extremity or whole‐body coils) the physiological response may have more significant effects.ConclusionIn modeling temperature increase during MRI of the human head in a head‐sized volume coil at up to 3.0 W/kg head‐average specific energy absorption rates, it may not be necessary to consider thermally induced changes in rates of metabolism, perfusion, perspiration, and radiation. J. Magn. Reson. Imaging 2008;28:1303–1308. © 2008 Wiley‐Liss, Inc.