bluuebunny/crossref_metadata_2025_split huggingface dataset:
Assessment of fraction of radiobiologically hypoxic cells in human melanoma xenografts by dynamic contrast‐enhanced MRI
Authors: Egeland Tormod A. M. , Gaustad Jon‐Vidar , Vestvik Ida K. , Benjaminsen Ilana C. , Mathiesen Berit , Rofstad Einar K. 
Published: February 2006

AbstractA noninvasive method for assessment of the extent of hypoxia in experimental and human tumors is highly needed. In this study, the potential usefulness of dynamic contrast‐enhanced magnetic resonance imaging (DCE‐MRI) was investigated, using gadopentetate dimeglumine (Gd‐DTPA) as contrast agent and A‐07 human melanoma xenografts as tumor model. DCE‐MRI was performed at a voxel size of 0.3 × 0.6 × 2.0 mm3 with spoiled gradient‐recalled sequences. Images of E · F (E is the initial extraction fraction of Gd‐DTPA and F is perfusion) and λ (the partition coefficient of Gd‐DTPA, which is proportional to extracellular volume fraction) were obtained by Kety analysis of DCE‐MRI data. The study was based on the hypothesis that hypoxic tissue would have low E · F (i.e., poor oxygen supply) and/or low λ (i.e., high cell density and, hence, high oxygen consumption rate). Twenty‐two tumors were first subjected to DCE‐MRI and then to measurement of fraction of hypoxic cells, using a radiobiological assay. E · F was found to be strongly correlated to fraction of hypoxic cells (P < 0.000001), whereas significant correlation between λ and fraction of hypoxic cells could not be detected. It is thus possible that E · F may be a useful parameter for the extent of hypoxia in experimental and human tumors with physiologic properties similar to those of A‐07 tumors. This possibility warrants further studies involving experimental tumors of several lines, as well as human tumors. Magn Reson Med, 2006. © 2006 Wiley‐Liss, Inc.
Electrophysiological subtypes and prognosis of childhood Guillain–Barré syndrome in Japan
Authors: Nagasawa Kasumi , Kuwabara Satoshi , Misawa Sonoko , Fujii Katsunori , Tanabe Yuzo , Yuki Nobuhiro , Hattori Takamichi , Kohno Yoichi 
Published: February 2006

AbstractGuillain–Barré syndrome (GBS) is classified into acute inflammatory demyelinating polyneuropathy (AIDP) and acute motor axonal neuropathy (AMAN), but little is known about the incidence of the subtypes and the prognosis of childhood GBS. To elucidate the features and long‐term prognosis, clinical and electrophysiological data for 31 Japanese GBS children were reviewed. By electrodiagnostic criteria, children were classified as having AIDP (35%) or AMAN (48%), or were unclassified (16%). The AMAN children invariably had normal sensory nerve potentials. Between the two groups, age, sex, and clinical disability did not differ significantly, but the AIDP children more frequently had cranial and sensory nerve involvement, and the AMAN children more frequently had preceding gastroenteritis. By 6 months after onset, all the AIDP and 80% of the AMAN children had regained the ability to walk; by 2 years, all but one of the AMAN children could walk. In Japanese childhood GBS, the proportion of AIDP and AMAN appears to be similar. Recovery is generally favorable in both subtypes, but some of the AMAN children experienced delayed recovery. Muscle Nerve, 2006
Effects of fiber compression and length distribution on the flexural properties of short kenaf fiber‐reinforced biodegradable composites
Authors: Shibata Shinichi , Fukumoto Isao , Cao Yong 
Published: February 2006

AbstractThe effects of the fiber compression and the length distribution on the flexural properties of short kenaf fiber‐reinforced biodegradable composites were investigated. Two types of kenaf (KU and KT) that were different in the density and the length distribution were used as reinforcements. These fibers were mixed with a corn–starch‐based resin, and the composite specimens were fabricated by a hot press forming. The flexural modulus in the KU specimens was not different from that in the KT, despite the difference of the fiber Young's modulus (KU 14.5 GPa and KT 22.1 GPa). This was because the KU was compressed more than the KT in the composite specimen because of the lower density structure. However, in the longest fiber (10.5 mm), the flexural strength in the KT specimens was considerably higher by 67% than that in the KU. The reason was that the KT did not include the fibers below the critical length (4.2 mm) because of the narrower fiber distribution than the KU. In fact, the flexural strength in the KT specimen significantly decreased with decrease in the average fiber length, which included the fibers below the critical length. Moreover, the flexural modulus agreed well with the calculated values by Cox's model that incorporated the effect of the fiber compression. POLYM. COMPOS. 27:170–176, 2006. © 2006 Society of Plastics Engineers
Accuracy of sequence alignment and fold assessment using reduced amino acid alphabets
Authors: Melo Francisco , Marti‐Renom Marc A. 
Published: February 2006

AbstractReduced or simplified amino acid alphabets group the 20 naturally occurring amino acids into a smaller number of representative protein residues. To date, several reduced amino acid alphabets have been proposed, which have been derived and optimized by a variety of methods. The resulting reduced amino acid alphabets have been applied to pattern recognition, generation of consensus sequences from multiple alignments, protein folding, and protein structure prediction. In this work, amino acid substitution matrices and statistical potentials were derived based on several reduced amino acid alphabets and their performance assessed in a large benchmark for the tasks of sequence alignment and fold assessment of protein structure models, using as a reference frame the standard alphabet of 20 amino acids. The results showed that a large reduction in the total number of residue types does not necessarily translate into a significant loss of discriminative power for sequence alignment and fold assessment. Therefore, some definitions of a few residue types are able to encode most of the relevant sequence/structure information that is present in the 20 standard amino acids. Based on these results, we suggest that the use of reduced amino acid alphabets may allow to increasing the accuracy of current substitution matrices and statistical potentials for the prediction of protein structure of remote homologs. Proteins 2006. © 2006 Wiley‐Liss, Inc.
Dynamics of pesticide residues in the autumn Chinese cabbage (Brassica chinensis L.) grown in open fields
Authors: Zhang Zhi‐Yong , Zhang Cun‐Zheng , Liu Xian‐Jin , Hong Xiao‐Yue 
Published: February 2006

AbstractResidues of the pesticides chlorpyrifos, dimethoate, cyhalothrin, cypermethrin, fenvalerate, deltamethrin and chlorothalonil in the autumn Chinese cabbage (Brassica chinensis L.) were studied using gas chromatography. The results indicated that the residues were dependent on the frequency and rate of pesticide application and on the weather conditions immediately following spraying. When the Chinese cabbages were treated once at normal rates, the half‐lives of the seven pesticides in the vegetable were 4.7, 5.3, 2.9, 3.5, 5.4, 4.3 and 4.0 days respectively. Thus, based on the recommended preharvest intervals, the residual levels of all pesticides were within the national standards. When the Chinese cabbages were treated four times at maximal rates at 5 day intervals, the half‐lives of chlorpyrifos, cypermethrin and chlorothalonil in the vegetable were 3.6, 2.9 and 5.9 days respectively, so that, based on the recommended preharvest intervals, the residual levels of chlorpyrifos and chlorothalonil exceeded the national standards for pollution‐free vegetables, but the residual level of cypermethrin was within the national standard. Effects of rain on pesticide final residues in plants treated four times were more significant than in those treated once. Copyright © 2006 Society of Chemical Industry
Ultra‐low flow nanospray for the normalization of conventional liquid chromatography/mass spectrometry through equimolar response: standard‐free quantitative estimation of metabolite levels in drug discovery
Authors: Valaskovic Gary A. , Utley Lucas , Lee Mike S. , Wu Jing‐Tao 
Published: February 2006

AbstractNanospray experiments were performed on an ensemble of drug molecules and their commonly known metabolites to compare performance with conventional electrospray ionization (ESI) and to evaluate equimolar response capabilities. Codeine, dextromethorphan, tolbutamide, phenobarbital, cocaine, and morphine were analyzed along with their well‐known metabolites that were formed via hydroxylation, dealkylation, hydrolysis, and glucuronidation. Nanospray exhibited a distinct trend toward equimolar response when flow rate was reduced from 25 nL/min to less than 10 nL/min. A more uniform response between the parent drug and the corresponding metabolites was obtained at flow rates of 10 nL/min or lower. The largest discrepancy was within ±50% for plasma samples. Nanospray was used as a calibrator for conventional ESI liquid chromatography/tandem mass spectrometry (LC/MS/MS) and normalization factors were applied to the quantitation of an acyl‐glucuronide metabolite of a proprietary compound in rat plasma. A nanospray calibration method was developed with the standard curve of the parent drug to generate quantitative results for drug metabolites within ±20% of that obtained with reference standards and conventional ESI. The nanospray method provides a practical solution for the quantitative estimation of drug metabolites in drug discovery when reference standards are not available. Copyright © 2006 John Wiley & Sons, Ltd.
Reactive Gas Pressure Syntheses of Nitride‐Diazenides and Hydridometalates
Authors: Auffermann Gudrun , Kniep Rüdiger , Bronger Welf 
Published: February 2006

AbstractNitride‐diazenides and hydridometalates (exemplified by the chemical systems Sr (Ba)‐N2 and Rb‐Pt‐H2) are obtained by reactive gas pressure syntheses in autoclaves starting from the elements and binary precursors, respectively. The formation of the nitride‐diazenides can be described in terms of reversible redox‐intercalation processes and that of the hydridometalates as reversible solid‐gas redox reactions. Phase formation and stability regions of the intermediate compounds of the chemical systems under consideration are particularly controlled by the level of the applied gas pressure.
Zu Grundfragen Anorganischer Festkörperchemie: Sind NaFeF3 [1] und CsFeF3 [2] ‚Perowskite’︁?
Authors: Hoppe Rudolf 
Published: February 2006

AbstractOn fundametal Questions of Inorganic Solid State Chemistry: Are NaFeF3 [1] and CsFeF3 [2] ‘Perovskites’?Even with simple molecules like C6H6 or C6H5CH3 ‘gross formulas’ like CH or C7H8 are nonsense. In the case of inorganic solids such procedures are even worse. For example by writing ‘K2Si4O9’ no hint is given concerning the specific characteristics of the structure. ‘CsFeF3’ hides the true composition, which in fact corresponds to 1Cs2iCs21iFe22Fe1iF32iF6. Therefore, it is essential that the correct formulas have to be added, which are based on point groups (PGr) of particles with exactly the same magnitude of infinitude of the partial lattice (PL). In addition, the connectivity of the PL must be indicated, e.g. [PtCl6]K2 or K2[Cl6Pt] instead of K2[PtCl6]. Therefore, the values of d(X‐M), C.P.(X/M), nECoN(X/M) (with n = 0, 1, n) of the anions have to be added to those of the cations M in the description of crystal structures. The ‘emancipation’ of the anions is urgent, since in most cases their connectivity reigns the utmost important structural features! Sometimes ‘on‐line‐formulas’ could be used indicating steric arrangements as shown here.
Synthesis and Crystal Structure of Two Lanthanide Complexes with Benzenecarboxylic Derivatives
Authors: Zhang Zheng‐Hua , Wan Shuang‐Yi , Okamura Taka‐aki , Sun Wei‐Yin , Ueyama Norikazu 
Published: February 2006

AbstractTwo novel lanthanide coordination polymers, [La(tpaa)3(H2O)2] (1) and [Eu2(BDC)3(DMF)2(H2O)2] (2) (Htpaa = terephthalamic acid, H2BDC = 1,4‐benzenedicarboxylic acid, DMF = N,N‐dimethylformamide), were hydro(solvo)thermally synthesized by reactions of the corresponding lanthanide nitrate salts with 1,3,5‐triazine‐2,4,6‐tri(4‐benzenecarboxylate) (L), in which a simultaneous hydrolysis of the ligand L occurred. Single‐crystal X‐ray analysis revealed that complex 1 comprises one‐dimensional chains that are further interlinked via hydrogen bonds, resulting in a two‐dimensional network; while complex 2 is a three‐dimensional interpenetrated coordination architecture.
Computational Magnetochemistry: Complementary Quantum Mechanical Tools
Authors: Eifert Thomas , Handrick Klaus , Hüning Felix , Neuhausen Ulrich , Schilder Helmut , Lueken Heiko 
Published: February 2006

AbstractMagnetic behaviour of condensed magnetic d and f systems with localised ‘magnetic electrons’ is essentially controlled by both single ion effects (interelectronic and spin‐orbit coupling, ligand field potential) and interionic exchange interactions. The latter act according to the spin dimensionality forced upon the magnetic centre via the single ion effects. For a complete understanding of magnetic behaviour on the basis of quantum mechanical models a two‐step procedure presents itself that determines in a complementary way first the ‘easy’ direction of the centres' magnetic dipoles connected with the single ion ground state. Subsequently, the relevant isotropic/anisotropic spin‐spin coupling model is applied (Heisenberg, XY, Ising). With the help of the textbook compounds CrBr3 and Cs3 CoCl5 as well as β‐RuCl3 the way of acting is pointed out.
Multivalent Complex Salts of Copper: Synthesis and X‐Ray Structural Analysis of [CuII(en)3][CuI4{(NNNPh)2C6H4}3] (en = ethylendiamine), an anionic Tris‐1,3‐bis(phenyltriazenide)benzene Complex of Tetrakis‐Copper(I)
Authors: Hörner Manfredo , Manzoni de Oliveira Gelson , Bortoluzzi Adailton João 
Published: February 2006

AbstractAn ethanolic solution of CuCl / ethylendiamine reacts with 1.3‐bis‐ (phenyltriazene)benzene in THF leading to the deprotonation of the bis triazene ligand to give orange crystals of [CuII(en)3][CuI4{(NNN‐Ph)2C6H4}3], an example of a rare complex salt of copper with mixed valence states. In the anion complex [CuI4{(NNNPh)2C6H4}3]2− the copper(I) ions are disposed linearly as single, bridged pairs in the two extremes of an axis, each of them presenting a trigonal bipyramidal alike coordination arrangement.
Kristallstruktur von Natrium‐Dihydrogencyamelurat‐Tetrahydrat Na[H2(C6N7)O3] · 4 H2O
Authors: Sattler Andreas , Schnick Wolfgang 
Published: February 2006

AbstractCrystal Structure of Sodium Dihydrogencyamelurate Tetrahydrate Na[H2(C6N7)O3] · 4 H2OSodium dihydrogencyamelurate‐tetrahydrate Na[H2(C6N7)O3]·4 H2O was obtained by neutralisation of an aqueous solution, previously prepared by hydrolysis of the polymer melon with sodium hydroxide. The crystal structure was solved by single‐crystal X‐ray diffraction ($P{\bar 1}$ a = 6.6345(13), b = 8.7107(17), c = 11.632(2) Å, α = 68.96(3), β = 87.57(3), γ = 68.24(3)°, V = 579.5(2) Å3, Z = 2, R1 = 0.0535, 2095 observed reflections, 230 parameters). Both hydrogen atoms of the dihydrogencyamelurate anion are directly bound to nitrogen atoms of the cyameluric nucleus, thus proving the preference of the keto‐tautomere in salts of cyameluric acid in the solid‐state. The compound forms a layer‐like structure with an extensive hydrogen bonding network.
Oxidative C‐C Coupling of Dilithium (2‐Pyridylmethanidyl)(tert‐butyldimethylsilyl)amide with White Phosphorus
Authors: Westerhausen Matthias , Kneifel Alexander N. , Mayer Peter 
Published: February 2006

Abstract(2‐Pyridylmethyl)(tert‐butyldimethylsilyl)amine (1) can be lithiated once or twice yielding lithium (2‐pyridylmethyl)(tert‐butyldimethylsilyl)amide (2) and dilithium (2‐pyridylmethanidyl)(tert‐butyldimethylsilyl)amide (3), respectively. The oxidation of 3 with white phosphorus yields dilithium 1,2‐dipyridyl‐1,2‐bis(tert‐butyldimethylsilylamido)ethane (4) which crystallizes after partial hydrolysis as an adduct of the form 2 · 4.
Knowledge, Wisdom, and the Philosopher
Authors: Kaufman Daniel A. 
Published: February 2006

The overarching thesis of this essay is that despite the etymological relationship between the word ‘philosophy’ and wisdom—the word ‘philosophos’, in Greek, means ‘lover of wisdom’—and irrespective of the longstanding tradition of identifying philosophers with ‘wise men’—mainline philosophy, historically, has had little interest in wisdom and has been preoccupied primarily with knowledge. Philosophy, if we are speaking of the mainline tradition, has had and continues to have more in common with the natural and social sciences than it does with the humanities and liberal arts.	In advancing this thesis, I divide the history of philosophy into three competing traditions: the mainline tradition of philosophy and two philosophical ‘countercultures,’ one conservative the other radical. At issue between these rival traditions is precisely the relative significance of knowledge and wisdom and their respective places in inquiry. I also provide an account of the distinction between knowledge and wisdom—which I argue is greater than has perhaps been appreciated—and between the natural and applied sciences, on the one hand, and the humanities and liberal arts on the other.
Developmental Differences in Spinal Cyclooxygenase 1 Expression after Surgical Incision
Authors: Ririe Douglas G. , Prout Heather D. , Barclay David , Tong Chuanyo , Lin Marina , Eisenach James C. 
Published: February 2006

Background
Systemic administration of a cyclooxygenase 1 (COX-1) inhibitor reduces hypersensitivity to mechanical stimuli after incisional paw surgery in 4-week-old, but not 2-week-old, animals. The purpose of the current study was to test whether this developmental difference was reflected by differences in COX-1 expression in the spinal cord after surgery.

Methods
Rats 2 and 4 weeks of age, paralleling infant and child human neurologic developmental stages, were used. A paw incision was made under general anesthesia and the withdrawal thresholds were measured before and after systemic and intrathecal administration of a COX-1 selective inhibitor (SC560). Immunohistochemistry was used to assess COX-1 protein in the spinal cord, and real-time polymerase chain reaction was used to quantify gene expression of COX-1 mRNA.

Results
Systemic and intrathecal administration of SC560 produced an increase in withdrawal threshold in the 4-week-old, but not in the 2-week-old, animals. Intrathecal SC560 increased withdrawal thresholds in the 4-week-old animals at a dose 100-fold less than with systemic administration. Cyclooxygenase 1 protein in the spinal cord was increased ipsilateral to surgery in the 4-week-old, but not in the 2-week-old, animals. Cyclooxygenase 1 mRNA was increased in the 4-week-old animals in the spinal cord ipsilateral to surgery relative to the contralateral side of the spinal cord, but not in the 2-week-old animals.

Conclusions
These results suggest that developmental differences in COX-1 expression in the spinal cord likely explain the lack of efficacy of COX-1 inhibitors in the 2-week-old rats. Whether this reflects a deficit in factors that stimulate COX-1 expression or a difference in response to these factors is not addressed, but should similar deficits occur in humans, COX-1 inhibitors may exhibit reduced efficacy in infants.
Obesity in Diabetic Patients Undergoing Coronary Artery Bypass Graft Surgery Is Associated with Increased Postoperative Morbidity
Authors: Pan Wei , Hindler Katja , Lee Vei-Vei , Vaughn William K. , Collard Charles D. 
Published: February 2006

Background
Despite the fact that obesity is a known risk factor for cardiovascular disease, many studies have failed to demonstrate that obesity is independently associated with an increased risk of cardiovascular morbidity and mortality in nondiabetic patients undergoing coronary artery bypass graft surgery. The authors investigated the influence of obesity on adverse postoperative outcomes in diabetic and nondiabetic patients after primary coronary artery bypass surgery.

Methods
A retrospective cohort study of patients undergoing primary coronary artery bypass surgery (n = 9,862) between January 1995 and December 2004 at the Texas Heart Institute was performed. Diabetic (n = 3,374) and nondiabetic patients (n = 6,488) were classified into five groups, according to their body mass index: normal weight (n = 2,148), overweight (n = 4,257), mild obesity (n = 2,298), moderate obesity (n = 785), or morbid obesity (n = 338). Multivariate, stepwise logistic regression was performed controlling for patient demographics, medical history, and preoperative medications to determine whether obesity was independently associated with an increased risk of adverse postoperative outcomes.

Results
Obesity in nondiabetic patients was not independently associated with an increased risk of adverse postoperative outcomes. In contrast, obesity in diabetic patients was independently associated with a significantly increased risk of postoperative respiratory failure (odds ratio [OR], 2.26; 95% confidence interval [CI], 1.41-3.61; P < 0.001), ventricular tachycardia (OR, 2.27; 95% CI, 1.18-4.35; P < 0.02), atrial fibrillation (OR, 1.56; 95% CI, 1.03-2.38; P < 0.04), atrial flutter (OR, 2.38; 95% CI, 1.29-4.40; P < 0.01), renal insufficiency (OR, 1.66; 95% CI, 1.10-3.41; P < 0.03), and leg wound infection (OR, 5.34; 95% CI, 2.27-12.54; P < 0.001). Obesity in diabetic patients was not independently associated with an increased risk of mortality, stroke, myocardial infarction, sepsis, or sternal wound infection.

Conclusion
Obesity in diabetic patients is an independent predictor of worsened postoperative outcomes after primary coronary artery bypass graft surgery.
Safety and Efficacy of the Cyclooxygenase-2 Inhibitors Parecoxib and Valdecoxib after Noncardiac Surgery
Authors: Nussmeier Nancy A. , Whelton Andrew A. , Brown Mark T. , Joshi Girish P. , Langford Richard M. , Singla Neil K. , Boye Mark E. , Verburg Kenneth M. 
Published: February 2006

Background
Valdecoxib and its intravenous prodrug parecoxib are reported to increase thromboembolic risk after coronary artery bypass grafting. The authors conducted a randomized trial to examine their safety and analgesic efficacy in patients recovering from major noncardiac surgical procedures.

Methods
The trial was randomized and double-blind, with 10 days of treatment and 30 days of follow-up. Patients (n = 1,062) received either parenteral parecoxib for 3 days and oral valdecoxib for the rest of the treatment period or placebo medications throughout. The frequency of predefined adjudicated postrandomization adverse events, including cardiovascular thromboembolism, renal dysfunction, gastroduodenal ulceration, and wound-healing complications, was assessed in each group. Secondary efficacy endpoints included patients' pain ratings, opioid analgesic consumption (recorded as morphine equivalents), and reports of opioid-related adverse effects.

Results
Predefined adjudicated adverse events had similar frequencies among patients who received parecoxib and valdecoxib (2.7%) and placebo patients (3.2%) (P = 0.58), including cardiovascular thromboembolic events (1.0% in each group; P = 1.0). Placebo patients consumed more morphine equivalents (66.2 +/- 92.4 mg) than did patients receiving parecoxib and valdecoxib (43.2 +/- 65.7 mg) (P < 0.001). Placebo patients had higher mean pain ratings on each of study days 2-10 (P < 0.01) and reported more opioid-related symptom distress on days 2-6 (P < 0.01).

Conclusions
Parecoxib and valdecoxib are useful adjuncts to opioids for the treatment of postoperative pain in noncardiac surgical patients. Further study will be required to determine the safety profile of parecoxib and valdecoxib administered to patients with known atherosclerotic disease after noncardiac surgery.