bluuebunny/crossref_metadata_2025 huggingface dataset:
Nonperturbative solutions for one‐dimensional Schrödinger equation with position‐dependent mass
Authors: Solimannejad Mohammad , Moayedi Seyed Kamran , Tavakoli Majid
Published: November 2005

In this article, we discuss the relationship between exact solvability of the position‐dependent mass Schrödinger equation with analytical solutions of an ordinary Schrödinger equation in quantum mechanics. Furthermore, it is demonstrated that nonperturbative solutions of ordinary Schrödinger equation for a sextic potential leads to a large class of exact solutions for the position‐dependent mass Schrödinger equation. © 2005 Wiley Periodicals, Inc. Int J Quantum Chem, 2006
Proton affinity of five‐membered heterocyclic amines: Assessment of computational procedures
Authors: Rao J. Srinivasa , Sastry G. Narahari
Published: November 2005

Ab initio quantum chemical calculations, G3B3, second‐order Møller–Plesset (MP2), and the hybrid density functional method B3LYP were employed to compute the proton affinities of 24 heterocyclic amines. A range of basis sets are employed, starting from double‐ζ polarization quality to triple‐ζ quality basis set with augmented diffuse and polarization function. Experimental values were used to calibrate the performance of various theoretical models. The regioselectivity for the protonation has been unambiguously established by performing B3LYP/6‐31G* calculations on the possible putative sites of attack. For the given series of compounds the performance of B3LYP/6‐31++G** and G3B3 levels of theory have been in excellent agreement with the experimental results with the deviations are of the order comparable with the experimental error. © 2005 Wiley Periodicals, Inc. Int J Quantum Chem, 2006
Theoretical study of initiated reaction mechanism of polymerization of maleic anhydride catalyzed by OH−1 anion
Authors: Xiao Hua , Feng‐Li Bei , Xin Wang , Xu‐Jie Yang , Lu‐De Lu
Published: November 2005

A theoretical study of the polymerization reaction mechanism of maleic anhydride (MA) initiated by hydrate is presented. The reaction pathway has been studied with the density functional theory (DFT) method at the B3LYP/6‐311G** level. The geometrical parameters of transition states (TS) are optimized; intrinsic reaction coordinate (IRC) calculations have also been performed to obtain further credible features. Frequency analyses of all the stationary points are calculated at the same basis sets. The total energies of all geometries are corrected at second‐order Møller–Plesset (MP2)/6‐311G**. Calculation results reveal that the reaction mechanism is attributable to anion polymerization. © 2005 Wiley Periodicals, Inc. Int J Quantum Chem, 2006
Semiclassical path integral theory of a double‐well potential in an electric field
Authors: Douvropoulos Theodosios G. , Nicolaides Cleanthes A.
Published: November 2005

A recently published methodology based on semiclassical path integral (SCPI) theory was implemented in the case of a model of a double‐well potential perturbed by a static electric field, with application to the inversion frequency of NH3. This model was chosen as an idealized case for testing of the present approach, as well as for quantum mechanical models that might be applied in the future. The calculations were concerned with the variation of the frequency of inversion as a function of field strength, F, and of distance, xf (from the symmetric point xo = 0), where the field is “felt.” It is found that this variation occurs sharply in very small regions of values of these parameters, and the system switches from internal oscillation to diffusion to the continuum. The fact that the theory is in analytic form allows the extraction of results and conclusions not only at the full SCPI level, but also at the Jeffreys–Wentzel–Kramers–Brillouin (JWKB) level. Comparison shows that the discrepancy sets in as the field strength increases, in accordance with the well‐known limitations of the JWKB method regarding its dependence on the degree of variation of the potential as a function of position. © 2005 Wiley Periodicals, Inc. Int J Quantum Chem, 2006
Energy levels of the hydrogen atom in a cylindrical cavity
Authors: Yurenev P. V. , Scherbinin A. V. , Pupyshev V. I.
Published: November 2005

Electronic states of the cylindrically confined hydrogen atom are studied numerically by the finite difference (FD) approach. Energies of the low‐lying states of the system are estimated vs. the radius R and length Z of the cylinder, as well as the position of the nucleus at the axis. Under the isotropic stretch of the cylinder with the constant ratio R = Z/2, the energy level picture reminds us that in the spherically confined atom: the energies of all states regularly grow up when decreasing the size of the cavity, and the states with the same principal n, but higher values of the angular l quantum number correspond to lower energies almost everywhere. Anisotropic stretch of the cylinder from prolate to the oblate one with constant volume causes numerous level intersections and avoided crossings, with the levels ordered as 1σ, 2π, 3δ, 2σ,…, in the prolate limit case, and as 1σ, 2π, 2σ, 3δ, 3π, 3σ,…, in the oblate limit case. The results of numerical calculations are in excellent agreement with qualitative consideration of the one‐electron system in the impenetrable cavity by using both variational and perturbative approaches. © 2005 Wiley Periodicals, Inc. Int J Quantum Chem, 2006
Large‐scale identification of human biliary proteins from a cholesterol stone patient using a proteomic approach
Authors: Zhou Hu , Chen Bin , Li Rong‐Xia , Sheng Quan‐Hu , Li Su‐Jun , Zhang Lei , Li Long , Xia Qi‐Chang , Wang Hong‐Yang , Zeng Rong
Published: November 2005

Gallbladder bile, one of the most important body fluids, is composed of water, inorganic ions, conjugated bile salts, phospholipids, cholesterol, bilirubin, mucin and proteins. The separation and identification of bile proteins remain difficult due to the complexity of this matrix. In the present study, human gallbladder bile was obtained from a cholesterol stone patient, and the proteins were isolated and purified by dialysis, precipitation and delipidation procedures. The resulting proteins were divided into several aliquots. One aliquot was subjected to two‐dimensional gel electrophoresis (2DE). The protein spots were then in‐gel digested and analyzed by liquid chromatography coupled with tandem mass spectrometry (LC/MS/MS). Another aliquot was directly digested and analyzed by a combination of strong cation‐exchange (SCX) and reversed‐phase (RP) chromatography prior to tandem mass spectrometry (2D‐LC/MS/MS). Eventually, 48 and 218 unique proteins were identified from 2DE/MS and 2D‐LC/MS/MS, respectively, resulting in a total of 222 unique identified proteins. Of the 218 proteins identified by 2D‐LC/MS/MS, 92 were identified based on more than one unique tryptic peptide, and, of the total 222 proteins, 98 were identified based on more than one unique tryptic peptide. Copyright © 2005 John Wiley & Sons, Ltd.
Characterization of intact Penicillium spores by matrix‐assisted laser desorption/ionization mass spectrometry
Authors: Chen Hun‐Yun , Chen Yu‐Chie
Published: November 2005

The fungal spores of Penicillium expansum, P. chrysogenum, P. citrinum, P. digitatum, P. italicum, and P. pinophilum were characterized by using matrix‐assisted laser desorption/ionization with time‐of‐flight mass spectrometry (MALDI‐TOFMS). These fungal spores are frequently found in grain and fruit. The mass spectra of these six species were directly obtained from the intact spores without any pretreatment. The results obtained indicate that 2,5‐dihydroxybenzoic acid and sinapinic acid are suitable matrices for the analysis of Penicillium spores. Characteristic ions representing the different species were obtained with sufficiently high reproducibility that these ions can be employed to identify the different fungal species. On the basis of these characteristic ions obtained from these authentic Penicillium spores, the approach was applied to characterize the fungal species contaminating the surfaces of fruit. It was demonstrated that the fungal spores directly scratched from the surfaces of fruit contaminated by unknown fungi can be rapidly identified using MALDI‐TOFMS analysis without any tedious pretreatment. Copyright © 2005 John Wiley & Sons, Ltd.
Use of electrospray ionization mass spectrometry for profiling of crude oil effects on the phospholipid molecular species of two marine bacteria
Authors: Mazzella Nicolas , Molinet Josiane , Syakti Agung Dhamar , Dodi Alain , Bertrand Jean‐Claude , Doumenq Pierre
Published: November 2005

We investigated the membrane lipid composition of two hydrocarbon‐degrading gram‐negative bacterial strains (Pseudomonas nautica IP 617 and Marinobacter hydrocarbonoclasticus) initially cultured on a soluble substrate, then on petroleum hydrocarbons, and finally taken back onto the soluble substrate. For the two strains, the growth on petroleum and the return to the initial medium showed major, but comparable, qualitative and quantitative modifications of the intact phospholipid molecular species (IPMS) composition. Furthermore, since bacterial membranes are mainly made up of phospholipids, these modifications reflected hydrocarbon assimilation, restoration abilities and membrane fluidity adaptation. The electrospray ionization mass spectrometry (ESI‐MS) analysis of intact phospholipid provided some new information (e.g. sn fatty acyl chain distribution) that could not be assessed by the classical fatty acid analysis. Moreover, such information should be particularly helpful with regards to bacterial taxonomy and xenobiotic toxicity studies. Copyright © 2005 John Wiley & Sons, Ltd.
Electrospray tandem mass spectrometry of underivatised acetylated xylo‐oligosaccharides
Authors: Reis Ana , Pinto Paula , Evtuguin D. V. , Neto Carlos P. , Domingues P. , Ferrer‐Correia A. J. , Domingues M. Rosário M.
Published: November 2005

Acetylated neutral (XylnAcm) and acidic xylo‐oligosaccharides (XylnAcmMeGlcA, and XylnAcmMeGlcAHex) obtained by partial acid hydrolysis of Eucalyptus globulus wood glucuronoxylans and fractionated by preparative ligand exchange/size‐exclusion chromatography were identified by electrospray ionisation mass spectrometry (ESI‐MS). Low molecular weight acetylated xylo‐oligosaccharides were studied by ESI‐tandem mass spectrometry (MS/MS). All the acetylated xylo‐oligosaccharides showed an abundant ion due to the neutral loss of 60 Da (CH3CO2H) in the MS/MS spectra. The presence of diacetylated xylo‐oligosaccharides was confirmed by the ions formed by loss of two molecules of acetic acid. Furthermore, characteristic [XylresAc2+Na]+ and [XylAc2+Na]+ ions, and ions due to loss of XylAc2, indicate that both acetyl groups are located in the same Xyl residue. On the other hand, losses of XylresAc and XylAc are also observed as well as [XylresAc+Na]+ and [XylAc+Na]+ , indicating the location of both acetyl groups in different Xyl residues, in some cases even in adjacent xyloses. The MS/MS spectra of triacetylated xylo‐oligosaccharides were complex due to the presence of different isobaric xylo‐oligosaccharides containing the acetyl groups at different locations in the xylo‐oligosaccharide backbone. In the MS/MS spectra of acidic xylo‐oligosaccharides, the ion at m/z 387, [XylresAcMeGlcA+Na]+, indicates that the acetyl groups are preferentially linked to Xyl substituted with MeGlcA. However, acidic xylo‐oligosaccharides with the acetyl and 4‐O‐methylglucuronic acid groups in different Xyl residues were also identified. In neutral and in acidic xylo‐oligosaccharides several possible locations of the acetyl groups were identified, namely at terminal positions. In summary, ESI‐MS/MS is shown to be a powerful tool for the characterisation of acetylated patterns in complex mixtures of oligosaccharides. Copyright © 2005 John Wiley & Sons, Ltd.
Analysis of proteins from a glioma cell line by using micro‐scale solution isoelectric focusing in combination with liquid chromatography/tandem mass spectrometry
Authors: Westman‐Brinkmalm Ann , Karlsson Gösta , Brive Lena M. , Hedberg‐Fogel Kristina , Persson Rita , Karlsson Hasse , Ekman Rolf , Blennow Kaj
Published: November 2005

In this study we have investigated whether micro‐solution isoelectric focusing (µsol‐IEF) can be used as a pre‐fractionation step prior to liquid chromatography/tandem mass spectrometry (LC/MS/MS) and if extensive sample purification of the different fractions is required. We found that, in spite of the high concentrations of buffer and detergents, no clean up of the digested µsol‐IEF fractions was necessary before analysis by LC/MS/MS. We also concluded that it is possible to identify at least twice as many proteins in a glioma cell lysate with the combination of µsol‐IEF and LC/MS/MS than with LC/MS/MS alone. Furthermore, most of the proteins that were identified from one µsol‐IEF fraction by using analytical narrow‐range two‐dimensional polyacrylamide gel electrophoresis (2D‐PAGE) and peptide mass fingerprinting with matrix‐assisted laser desorption/ionization time‐of‐flight mass spectrometry (MALDI‐TOFMS) were also identified by LC/MS/MS. Finally, we used the combination of µsol‐IEF and LC/MS/MS to compare two sample preparation methods for glioma cells and found that several nuclear, mitochondria, and endoplasmic reticulum proteins were only present in the sample that had been subjected to lipid extraction by incubating the homogenized cells in chloroform/methanol/water. Copyright © 2005 John Wiley & Sons, Ltd.
Characterisation and proposed origin of mass spectrometric ions observed 30 Th above the ionised molecules of per‐O‐methylated carbohydrates
Authors: Robinson Sarah , Routledge Anne , Thomas‐Oates Jane
Published: November 2005

Derivatisation of carbohydrates by permethylation significantly improves the mass spectrometric intensity of carbohydrate‐derived ions and allows more readily interpretable fragmentation; in addition, samples are conveniently separated from salts, and larger oligosaccharides are more readily ionised. It has previously been recognised that, in the mass spectra of permethylated carbohydrates, a series of ions indicating species 30 Da larger than the fully methylated carbohydrate molecules are also observed. These species have not been characterised in the literature despite their apparently ubiquitous occurrence in the mass spectra of permethylated carbohydrates. Tandem mass spectrometry (MS/MS) experiments were performed on permethylated carbohydrates and reduced permethylated carbohydrates that exhibit the artefact, demonstrating that the artefact is not reducing terminal specific, and that the artefact can be introduced at any hydroxyl residue. It was further demonstrated through the use of different alkylation reagents that the origin of this artefact group is the alkylating reagent itself. It is proposed that side reactions that occur between the permethylation reagents allow the production of small amounts of iodomethyl methyl ether. This reagent can then compete with methyl iodide for reaction with the carbohydrate OH groups. The result is partial incorporation of a methoxymethyl moiety instead of a methyl group, detected as ‘+30’ artefact ions. Copyright © 2005 John Wiley & Sons, Ltd.
Threshold values of random K‐SAT from the cavity method
Authors: Mertens Stephan , Mézard Marc , Zecchina Riccardo
Published: November 2005

Using the cavity equations of Mézard, Parisi, and Zecchina Science 297 (2002), 812; Mézard and Zecchina, Phys Rev E 66 (2002), 056126 we derive the various threshold values for the number of clauses per variable of the random K‐satisfiability problem, generalizing the previous results to K ≥ 4. We also give an analytic solution of the equations, and some closed expressions for these thresholds, in an expansion around large K. The stability of the solution is also computed. For any K, the satisfiability threshold is found to be in the stable region of the solution, which adds further credit to the conjecture that this computation gives the exact satisfiability threshold.© 2005 Wiley Periodicals, Inc. Random Struct. Alg., 2006
The impact of endogenous demand on push–pull production systems
Authors: Gonçalves Paulo , Hines Jim , Sterman John
Published: November 2005

Though often analyzed separately, supply chain instability and customer demand interact through product availability. We investigate the feedback between supply chain performance and demand variability in a model grounded in a first‐hand study of the hybrid push–pull production system used by a major semiconductor manufacturer. While customers' response to variable service levels represents an important concern in industry, with sizeable impacts on company profitability, previous models exploring supply chain instability do not account for it. This research incorporates two effects of customer responses to availability. The sales effect captures the negative feedback whereby product shortages cause customers to seek alternative sources of supply, reducing demand and easing the shortage. The production effect captures the delayed impact of changes in demand on the manufacturer's production decisions: lower demand leads to reduced production, prolonging shortages that depress demand, a destabilizing positive feedback. We show how the sales and production effects interact to destabilize the supply chain and lower average performance. Supply chain models that assume exogenous demand may therefore underestimate the amplification in the chain and the value of inventory buffers. In addition, incorporating the customer response leads to different inventory and utilization policies from those in use by the company. The model yields insights into the costs of lean inventory and responsive utilization policies in the context of hybrid production systems and endogenous demand. Copyright © 2005 John Wiley & Sons, Ltd.
Upstream versus downstream information and its impact on the bullwhip effect
Authors: Croson Rachel , Donohue Karen
Published: November 2005

This paper reports the results of an experiment to examine whether giving supply chain partners access to downstream inventory information is more effective at reducing bullwhip behavior, and its associated costs, than similar access to upstream inventory information. Bullwhip behavior refers to the tendency of orders to increase in variation as they are passed upstream in a supply chain (i.e., away from the final consumer). We use a controlled version of the Beer Distribution Game as the setting for our experiment, and vary the amount and location of inventory information shared across treatments. We first independently test whether sharing upstream or downstream inventory information helps reduce bullwhip behavior, and find that only downstream information sharing leads to significantly lower order oscillations throughout the supply chain. We then compare the reduction in order oscillations experienced by supply chain level and find that upstream supply chain members benefit the most from downstream information sharing. Copyright © 2005 John Wiley & Sons, Ltd.
Studies of carbon behaviour on GaN surface in ultra high vacuum (UHV)
Authors: Diale M. , Auret F. D. , Odendaal R. Q. , Roos W. D.
Published: November 2005

In this study, AES was used to thermally clean GaN surfaces, and analysis was done as the temperature was gradually increased. Heating samples to 1010 °C resulted in nearly stoichiometric and contamination‐free surfaces. The behaviour of carbon on the GaN surface was studied with sputtering in AES. It was found that C was a surface issue than a crystal problem. XPS was used to identify the chemical state of the contaminants on the surface of as‐grown GaN. These were found to be in the form of gallium oxides, hydroxides, graphite and carbides. Copyright © 2005 John Wiley & Sons, Ltd.
Rh2[MTPA]4, a dirhodium complex as NMR auxiliary for chiral recognition
Authors: Duddeck Helmut
Published: November 2005

The dirhodium complex Rh(+II)2[(+)‐MTPA]4 is introduced as an NMR auxiliary for enantiodifferentiation. As a soft Lewis acid, it is particularly useful for the recognition of soft Lewis base molecules. The donor properties of ligands can be divided into several categories and are exemplified by various classes of phosphorus‐containing functionalities. In addition, the thermodynamics of the underlying ligand–complex equilibria are discussed and stereochemical implications demonstrated. The extension of the dirhodium method to absolute configuration determination is evaluated. The outlook for future applications with further non‐phosphorus ligands is presented. © 2005 The Japan Chemical Journal Forum and Wiley Periodicals, Inc. Chem Rec 5: 396–409; 2005: Published online in Wiley InterScience (www.interscience.wiley.com) DOI 10.1002/tcr.20059
Natural and edible biopolymer poly‐γ‐glutamic acid: synthesis, production, and applications
Authors: Sung Moon‐Hee , Park Chung , Kim Chul‐Joong , Poo Haryoung , Soda Kenji , Ashiuchi Makoto
Published: November 2005

Poly‐γ‐glutamic acid (γ‐PGA) is a very promising biodegradable polymer that is produced by Bacillus subtilis. γ‐PGA is water‐soluble, anionic, biodegradable, and edible. This paper reviews the production of a strain of γ‐PGA and recent developments with respect to applications in terms of Ca absorption, moisturizing properties, γ‐PGA conjugation, super absorbent polymer, and so on. Our recent research shows that γ‐PGA can be used as an immune‐stimulating and anti‐tumor agent, especially at high molecular weight. © 2005 The Japan Chemical Journal Forum and Wiley Periodicals, Inc. Chem Rec 5: 352–366; 2005: Published online in Wiley InterScience (www.interscience.wiley.com) DOI 10.1002/tcr.20061
Cervical assessment at 22 and 27 weeks for the prediction of spontaneous birth before 34 weeks in twin pregnancies: is transvaginal sonography more accurate than digital examination?
Authors: Vayssière C. , Favre R. , Audibert F. , Chauvet M. P. , Gaucherand P. , Tardif D. , Grangé G. , Novoa A. , Descamps P. , Perdu M. , Andrini E. , Janse‐Marec J. , Maillard F. , Nisand I.
Published: November 2005

Objectives

This study compared the accuracy of ultrasound cervical assessment (cervical length and cervical index) and digital examination (Bishop score and cervical score) in the prediction of spontaneous birth before 34 weeks in twin pregnancies.

Methods

In a prospective multicenter study, digital examination and transvaginal sonography were performed consecutively in twin pregnancies attending for routine sonography at either 22 weeks (175 women) or 27 weeks (153 women). The digital examination took place first, and the Bishop score and cervical score (cervical length minus cervical dilatation) were calculated. Ultrasound measurements were then made of cervical length and funnel length to yield the cervical index (1 + funnel length/cervical length). The association between each variable and delivery before 34 weeks was tested by the Mann–Whitney U‐test. The receiver–operating characteristics (ROC) curves of the ultrasound and digital indicators were determined for both gestational age periods, and the areas under the ROC curves compared. The best cut‐off values for each indicator were used to determine predictive values for delivery before 34 weeks.

Results

The median gestational age at delivery among the women included in the 22‐week examination period was 36.0 (range, 21–40) weeks; 10.9% (19) gave birth spontaneously before 34 weeks. The median cervical length was 40 (range, 6–65) mm. All four parameters were predictors of delivery before 34 weeks. The areas under the ROC curves for cervical index, cervical length, Bishop score and cervical score did not differ significantly. The median gestational age at delivery among the women in the 27‐week examination period was 36.0 (range, 27–40) weeks; 9.2% (14) gave birth spontaneously before 34 weeks. The median cervical length was 35 (range, 1–57) mm. All parameters except the Bishop score were predictors of delivery before 34 weeks. The likelihood ratio of the positive and negative tests for cervical length ≤ 25 mm was 5.4 (range, 3.2–9.0) and 0.3 (range, 0.1–0.7), respectively, compared with 2.3 (range, 1.3–4.2) and 0.6 (range, 0.3–1.1), respectively, for cervical score ≤ 1. The area under the curve for the cervical index was significantly larger than that for the Bishop score (P = 0.008) or cervical score (P = 0.02).

Conclusion

Transvaginal sonography predicted spontaneous delivery before 34 weeks better than digital examination at the 27‐week but not the 22‐week examination. Copyright © 2005 ISUOG. Published by John Wiley & Sons, Ltd.
Sonographic characteristics of linear nevus sebaceous sequence
Authors: Neis A. E. , Johansen K. L. , Harms R. W. , Watson W. J. , Brost B. C.
Published: November 2005

Linear nevus sebaceous is a hamartomatous lesion most commonly seen on the face and head of infants and diagnosed after birth. We describe a patient with sonographic findings of linear nevus sebaceous seen initially at 30 weeks' gestation. Other associated sonographic findings include macrocephaly and polyhydramnios. When associated with a midline soft tissue mass, these findings are highly suggestive of the presence of congenital linear nevus sebaceous sequence. Copyright © 2005 ISUOG. Published by John Wiley & Sons, Ltd.
Dissection of the molecular basis of mycophenolate resistance in Saccharomyces cerevisiae
Authors: Harley Jenks M. , Reines Daniel
Published: November 2005

IMP dehydrogenase (IMPDH) is required for the de novo synthesis of guanine nucleotides. While most invertebrates have one IMPDH gene and humans and mice have two, Saccharomyces cerevisiae contains four, IMD1–IMD4. Although Imd2 is 92% identical to Imd3, it is the only S. cerevisiae IMPDH that is resistant to mycophenolic acid in vitro and is the only one of the four that supports drug‐resistant growth. Thus, S. cerevisiae is unique in possessing two classes of IMPDH enzymes with very different drug susceptibilities. The mycophenolate‐sensitive growth phenotype has become an important genetic tool in yeast, particularly as an indicator for mutations in the transcription elongation machinery. Here we exploit the distinct drug sensitivity of these two closely related IMPDH genes to identify the naturally occurring determinants of drug‐resistant growth. Using chimeric IMD2–IMD3 genes in a strain null for IMD genes, we show that one of the 39 amino acid differences between these enzymes is responsible for much of its drug resistance. The IMP dehydrogenase activity of purified chimeric Imd3 containing the Imd2 residue at position 253 was eight‐fold more resistant than native Imd3. The reciprocal change in Imd2 resulted in a 23‐fold loss of resistance. Hence, acquisition of a hydroxyl side‐chain at 523 is sufficient to confer a drug‐resistant phenotype upon this organism. We identified the major determinant of the functional distinction between IMD genes in this yeast and suggest that selective pressure on this species forced divergence of one member of this gene family toward drug resistance. Copyright © 2005 John Wiley & Sons, Ltd.
Physiological role of D‐aspartate oxidase in the assimilation and detoxification of D‐aspartate in the yeast Cryptococcus humicola
Authors: Takahashi Shouji , Kakuichi Taiki , Fujii Kazuhito , Kera Yoshio , Yamada Ryo‐hei
Published: November 2005

The physiological role of D‐aspartate oxidase (ChDASPO) in the yeast Cryptococcus humicola was analysed through the growth characteristics of a ChDASPO gene‐disrupted strain (daspoΔ) and the expression profile of ChDASPO on various combinations of carbon and nitrogen sources. The daspoΔ strain, constructed by homologous integration of the yeast URA3 marker, grew as well as the wild‐type strain on ammonium chloride, L‐aspartate or D‐alanine as the sole nitrogen source. In contrast, the daspoΔ strain did not grow at all on D‐aspartate, not only as the sole nitrogen source but also as the sole carbon source or as the sole nitrogen and carbon source, and grew more slowly than the wild‐type strain on D‐glutamate as the sole nitrogen source. In the wild‐type strain, the induction of ChDASPO activity strictly depended on the presence of D‐aspartate and was little affected by the co‐presence of ammonium chloride, but it was significantly reduced by the co‐presence of both glucose and ammonium chloride, which, however, did not abolish the induction, allowing considerable expression of ChDASPO. This expression pattern was consistent with that shown by Northern blot analysis. The daspoΔ strain was more sensitive than the wild‐type to the growth retardation by acidic D‐amino acids, but not to that by the corresponding L‐isomers or D‐alanine. These results clearly show that in the yeast, DASPO plays an essential role in the assimilation of D‐aspartate and acts as a detoxifying agent for D‐aspartate. Copyright © 2005 John Wiley & Sons, Ltd.
Body weight as an effective tool for determination of onset of puberty in captive female Nile hippopotami (Hippopotamus amphibious)
Authors: Wheaton Catharine J. , Joseph Sharon , Reid Kelly , Webster Tricia , Richards Mary , Savage Anne
Published: November 2005

Profiles of fecal progestogens and body weight from the early juvenile to the peri‐pubertal period are presented for eight captive female Nile hippopotami housed at Disney's Animal Kingdom in Florida. Average growth rate in juveniles was 0.85±0.03 kg/day (r2=0.913). Progestogen elevations were detectable as early as 16.8 months of age, and elevations indicative of ovulation and luteal activity were identified in seven of eight females by 30.3±1.6 months of age and body weight of 829.3±49.4 kg. Progestogen patterns before the onset of puberty were highly variable within and between females. Some females remained at baseline concentrations, whereas in others the progestogen pattern was characterized by infrequent, transient elevations of low amplitude and shortened duration. Four females were monitored through onset of puberty, conception, and first pregnancy. Onset of puberty was defined as the first luteal phase from the series of consecutive ovarian cycles culminating in conception and was observed at 34.9±2.2 months of age and 963.6±39.4 kg, however, the quality and number of cycles varied among females before conception. Females conceived between 2.7–3.9 years of age after attaining an approximate threshold body weight of 1,000 kg (1,070.5±39.5 kg). The age at first conception in captivity occurs at a younger age than has been reported for wild populations. Body weight may be an effective tool for approximating the state of reproductive maturity and facilitate collection management in zoos. Zoo Biol. 0:1–13, 2005. © 2005 Wiley‐Liss, Inc.
Anuran gender identification by fecal steroid analysis
Authors: Szymanski D.C. , Gist D.H. , Roth T.L.
Published: November 2005

This study tested the hypothesis that steroid hormone metabolites can be measured in anuran feces and their concentrations used to identify the sex of adults. Fecal samples from American toads, Bufo americanus, and boreal toads, B. boreas boreas, were extracted using ethyl acetate, and the concentrations of estradiol, progesterone and testosterone metabolites were measured by enzyme immunoassays with antibodies commonly used to evaluate steroid hormone concentrations in mammalian species. In American toads, mean testosterone metabolite concentrations (P<0.05) between males (224.3±15.5 ng/g feces) and females (80.7±10.6 ng/g), but estradiol and progesterone metabolite concentrations did not. In contrast, estradiol immunoreactivity differed (P<0.05) between male (19.0±1.8 ng/g) and female (48.3±6.3 ng/g) boreal toads. Progesterone and testosterone metabolite concentrations did not differ. Fecal hormone metabolite analysis offers a promising noninvasive approach to gender identification in anuran amphibians. However, the group of metabolites differentiating gender may not be consistent among species. Zoo Biol 0:1–12, 2005. © 2005 Wiley‐Liss, Inc.
Gastro‐Intestinal transit time in South American deer
Authors: de Oliveira Luciana Domingues , Duarte José Maurício Barbanti
Published: November 2005

The study of diet and physiological peculiarities of the digestive system of neotropical deer is not well known and the literature shows inconsistencies. To better understand the digestive system of these mammals the difference in the gastro‐intestinal transit time of four species of neotropical deer (Mazama americana, Mazama gouazoubira, Mazama nana, Blastocerus dichotomus), kept in captivity, was evaluated. Four plants (Neonotonia wightii, Morus albans, Medicago sativa, Leucaena leucocephala) were utilized and two variables were measured, mean time of the beginning of the elimination (BE) and mean time of permanence (TP). The results obtained for BE indicated similarity among the deer species, with significant differences between M. gouazoubira (mean=13.62 hr) and M. Americana (mean=19.25 hr). For the plants, the BE was faster with N. wightii and L. leucocephala, and slower for M. sativa. The TP results for B. dichotomus showed longer time when compared to the other species, whereas M. gouazoubira had a lower permanence. Overall, N. wightii had the highest retention time in the digestive tract of all the deer species studied. Associated with this observation, N. wightii had the highest quantity of plant fiber of the plants tested. In a similar fashion M. sativa showed the lowest TP in the digestive tract of the deer and had the lowest quantity of acid detergent fiber. The data from this study showed that, within species, the shape of the excretion curve of the plants was similar when the animals consumed N. wightii or M. sativa. Blastocerus dichotomus and M. gouazoubira had the highest and the lowest gastro‐intestinal transit time, respectively. This suggests that these species characterize different abilities to digest high fiber food, and consequently, represent the two extremities in the morphophysiological adaptation within the deer species evaluated. This information is vital because it is important to know the digestive physiology to define the diet of captive animals, particularly regarding the quantity and quality of fiber. Zoo Biol 0:1–11, 2005. © 2005 Wiley‐Liss, Inc.
Air Gun Pellet Injuries of the Hand
Authors: AL-QATTAN M. M.
Published: November 2005

The purpose of this paper is to report our experience in a group of patients who suffered injuries by air gun pellets to the hand. There were 22 males and 2 females, with a mean age of 12 years. The pellet was embedded in the hand in 18 patients and it went through and through in the remaining six. There were no vascular injuries. Associated injuries to tendon, nerve or bone occurred in six patients. There was little soft-tissue devitalization and none of the fractures required fixation or splinting. Immediate postoperative mobilization resulted in full range of motion in all patients. In conclusion, pellets produce a different injury pattern, with a more benign course, than other types of bullet injury.
Results of Tri-Ligament Tenodesis: A Modified Brunelli Procedure in the Management of Scapholunate Instability
Authors: TALWALKAR S. C. , EDWARDS A. T. J. , HAYTON M. J. , STILWELL JOHN H. , TRAIL I. A. , STANLEY J. K.
Published: November 2005

One hundred and sixty-two patients with a diagnosis of scapholunate instability underwent a modified Brunelli procedure over a 7-year period. One hundred and seventeen were assessed with the help of a questionnaire and, of these, 55 patients attended for clinical evaluation. The mean follow-up was 4 (1–8) years. There were 72 patients with dynamic scapholunate instability and 45 patients with static instability. The average age was 38 years. There were 50 males and 67 females. A total of 77 (62%) patients had no to mild pain with a mean visual analogue score of 3.67 (SD = 2.5). The loss in the arc of flexion–extension was due to a reduced range of flexion (mean loss 31%), while 80% of extension was maintained, compared with the contralateral side. The grip strength on the operated side was reduced by 20% of the non-operated side. There was no statistically significant difference ( P>0.05). in the range of movement or the grip strength between the static and dynamic group and patients with or without legal claims. Ninety (79%) patients were satisfied with the result of the surgery (good to excellent) and 88% of the patients felt that they would have the same surgery again. We feel that these results compare favourably with the early results published from this unit and recommend this procedure for dynamic and static scapholunate instability.
Dorsal Fracture Dislocations of the Proximal Interphalangeal Joint Treated by Open Reduction and Interfragmentary Screw Fixation: Indications, Approaches and Results
Authors: LEE J. Y. L. , TEOH L. C.
Published: November 2005

Many operative and non-operative treatments of dorsal fracture dislocations of the proximal interphalageal (PIP) joint have been described. Return of good joint function requires anatomical reduction of the articular fragments and restoration of joint congruity and a stable functional arc of motion, with the fixation construct stable enough for early mobilization. To prevent recurrent dorsal subluxation, the attachments of the ligamentous palmar restraints and the bony buttress provided by the palmar lip of the middle phalanx base must be restored. Open reduction and internal interfragmentary screw fixation using 1.5 or 1.3 mm screws was employed in 12 fingers in 10 patients with unstable dorsal fracture dislocations of the PIP joints of Schenck grades III and IV. At an average follow-up of 8.7 months, all patients in this series achieved good to excellent results and an average total active interphalangeal motion of 132° (range 105°–165°). Additional benefits over non-operative techniques included improved patient comfort and simplified nursing care and therapy supervision.
The Significance of Extensor Tendon Tethering and Dorsal Joint Capsule Tightening After Injury to the Hand
Authors: KULKARNI M. , HARRIS S. B. , ELLIOT D.
Published: November 2005

This paper examines the clinical problem of extensor tendon tethering and/or dorsal joint capsule tightening secondary to hand injury. One hundred and forty-one patients were examined 13 to 51 months after hand injuries of varying severity. Fifty-six patients (40%) had suffered simple and eighty-five patients (60%) complex injuries. Seventy-four (52%) of the 141 patients had no extensor tendon tethering and/or dorsal joint capsule tightening. In 30 (21%), the extensor tendon tethering and/or dorsal joint capsule tightening was considered to be “obvious” in that it was easily seen on examination using various commonly used clinical tests of finger flexion and extension. In 37 (26%), the extensor tendon tethering and/or dorsal joint capsule tightening was considered to be of “lesser degree” because it was only evident on application of specific tests which are described in this paper. Of the 37, 21 (56%) described themselves as being unable to make a “proper” fist with the injured hand, 33 (89%) had pain or discomfort on the dorsum of the injured hand and/or fingers on gripping ( P < 0.01) and 25 (70%) had weakness of power of gripping ( P < 0.01). Thirty-two (87%) complained of functional problems at work, with activities of daily living or with the pursuit of their hobbies.
Carpal Tunnel Syndrome and Flexion Contracture of the Digits in a Child with Familial Hypercholesterolaemia
Authors: YENSEL U. , KARALEZLI N.
Published: November 2005

This paper presents a 9 year-old girl who had flexion contracture of digits, carpal tunnel syndrome and multiple xanthomas covering the extremities.
Normal audiologic presentations in patients with acoustic neuroma: An evaluation using strict audiologic parameters
Authors: Magdziarz Daniel D. , Wiet Richard J. , Dinces Elizabeth A. , Adamiec Lois C.
Published: November 2005

Although several studies have previously reported on patients presenting with “normal” audiologic parameters in acoustic neuroma, the present study is, to our knowledge, the first to exclusively examine in detail cases involving exceptionally stringent objective audiometric features. Of 369 patients with acoustic neuroma who were operated on between April 1980 and April 1997 by our group, 10 had strictly normal hearing, defined as follows: (1) pure‐tone average < 20 dB; (2) speech discrimination score > 90%; and (3) interaural differences < 10 dB at every hertz level. A high level of audiologic functioning was found to significantly lower the sensitivity of auditory brainstem response in the detection of acoustic neuroma. Magnetic resonance imaging was the only preoperative test exhibiting 100% sensitivity in this setting. Thus, a high level of clinical suspicion appears warranted in any case involving unexplained unilateral audio‐vestibular symptoms—including those instances in which strictly normal hearing parameters exist and are associated with negative auditory brainstem response findings.
Vestibular autorotation testing in patients with benign paroxysmal positional vertigo
Authors: Belafsky Peter , Gianoli Gerard , Soileau James , Moore David , Davidowitz Sheri
Published: November 2005

OBJECTIVES

The current gold standard for diagnosis of benign paroxysmal positional vertigo (BPPV) is the Dix‐Hallpike maneuver. However, because of fatigability, the Dix‐Hallpike is often falsely normal. The objective of this study was to evaluate the utility of vestibular autorotation testing in the diagnosis of BPPV.

METHODS

The charts of 210 patients at a tertiary referral center for vertiginous disorders were reviewed. All patients underwent clinical evaluation, Dix‐Hallpike testing, audiometry, electronystag‐mography, and vestibular autorotation testing. The vestibular autorotation results of patients with BPPV were compared with the findings in patients with non‐BPPV vestibular disorders. The sensitivity and specificity of vestibular autorotation testing in diagnosing BPPV were calculated.

RESULTS

Ninety‐one patients (42.9%) had BPPV, 76 patients (36.2%) had vertigo of uncertain cause, 28 (13.3%) had unilateral vestibular hypofunction, 9 patients (4.3%) had Meniere's disease, and 2 patients (1.0%) had perilymphatic fistula. Patients with BPPV were 3.32 times more likely to have a normal horizontal gain (95% CI = 1.54‐7.19). A normal horizontal gain is 85% sensitive but only 36% specific for BPPV. Patients with BPPV were 1.9 times more likely to have vertical phase lead (95% CI = 0.953.93). Patients with BPPV were 2.20 times more likely to have both normal horizontal gain and vertical phase lead (95% CI = 1.03‐4.69) The sensitivity of the combination of normal horizontal gain and vertical phase lead on vestibular autorotation testing is 87% specific but only 25% sensitive in the diagnosis of BPPV.

CONCLUSION

A normal horizontal gain or vertical phase lead on vestibular autorotation testing in a vertiginous patient is suggestive of but not exclusive to a diagnosis of BPPV. The combination of a normal horizontal gain and vertical phase lead on vestibular autorotation testing is highly suggestive of the diagnosis of BPPV. Adjuvant use of these parameters in vestibular autorotation testing may prove to be helpful in the diagnosis of BPPV.
Postmeningitic ossification in pediatric cochlear implantation
Authors: Young Nancy M. , Hughes C. Anthony , Byrd Sharon E. , Darling Crystal
Published: November 2005

OBJECTIVE

The goals of this study were to retrospectively review high‐resolution CTs (HRCTs) of pediatric postmeningitic cochlear implant recipients and to correlate results with surgical findings.

METHODS

HRCTs of 20 children (11 months to 12 years old) who underwent implantation with multichannel devices were reviewed. Results were correlated with the degree of ossification observed at surgery.

RESULTS

Ninety percent of subjects required drilling of ossified bone within the basal turn at surgery. HRCT of the cochleas suggested ossification within the basal turn in 45% (50% sensitivity). Ossification of the lateral semicircular canal on HRCT was present in 72% (77% sensitivity). Five of 6 cases without radiographic evidence of ossification had positive findings at surgery.

CONCLUSION

Ossification is a common occurrence in postmeningitic deaf children. Ossification of the lateral semicircular canal on HRCT is a more sensitive measure for predicting ossification than evidence of cochlear involvement. Absence of ossification on HRCT is no guarantee of cochlear patency at the time of implantation.
Evaluation of a new procedure for nasal alar rim and valve collapse: Nasal alar rim reconstruction
Authors: Troell Robert J. , Powell Nelson B. , Riley Robert W. , Li Kasey K.
Published: November 2005

OBJECTIVE

A new operative technique to improve nasal valve collapse by placement of cartilage struts along the alar rim was compared with the standard nasal valve cartilage graft (NVG) technique.

METHODS AND PATIENTS

A retrospective study of consecutive patients with nasal valve collapse was performed at Stanford University Medical Center. Seventy‐nine patients with nasal valve collapse underwent reconstruction with either the classic NVG technique or a newly developed nasal alar rim reconstructive (NARR) procedure. The mean age of the NARR group was 50.13 years (SD ± 9.40), with 36 men (92.3%) and 3 women (7.7%). The mean age of the NVG group was 52.14 years (SD ± 10.83), with 36 men (90%) and 4 women (10%).

MAIN OUTCOME MEASURES

These included functional and subjective evaluation of nasal valve collapse.

RESULTS

Forty patients (50.6%) underwent the NVG technique, and 39 (49.4%) received the NARR procedure. The NVG technique revealed 0% worsened, 15.0% (6/40) unchanged, 25.0% (10/40) improved, and 60% (24/40) free of obstruction. The NARR procedure revealed 2.6% worsened, 2.6% unchanged, 7.7% improved, and 87.1% free of obstruction.

CONCLUSIONS

Nasal alar cartilage struts placed along the caudal alar rim offers sufficient support to the alar rim and valve area. This procedure appears to be as effective as currently available reconstructive alternatives, while being technically uncomplicated.
Postoperative treatment of the patient with obstructive sleep apnea
Authors: Ulnick Keith M. , Debo Richard F.
Published: November 2005

>OBJECTIVE

The postoperative management of patients with obstructive sleep apnea syndrome (OSAS) has been based primarily on the potential loss of the airway. Our hypothesis is that not all patients with OSAS require placement in the intensive care unit after surgery.

METHODS

We undertook a prospective, nonrandomized study (N = 38). Data included demographics, polysomnograms, body mass index (BMI), and postoperative course, including any complications within 72 hours.

RESULTS

The average respiratory disturbance index was 66, and the average BMI was 29. The average preoperative and postoperative maximal arterial oxygen desaturation values were 82% and 94%, respectively. Patients with BMIs less than 35 did not have desaturation values below 90%. No complications occurred.

DISCUSSION

Within the first 72 hours after surgery, no complications were observed in our study groups. Patients with BMIs greater than 35 were at increased risk for postoperative desaturations. The uncomplicated OSAS patient, one without significant comorbid factors, can be treated in a safe and prudent fashion outside of an intensive care unit.