bluuebunny/crossref_metadata_2025 huggingface dataset:
Correlates of current cigarette smoking among in-school adolescents in the Kurdistan region of Iraq
Authors: Siziya Seter , Muula Adamson S , Rudatsikira Emmanuel
Published: December 2007

Background

Many adult cigarette smokers initiated the habit as adolescents. Adolescent tobacco use may be a marker of other unhealthy behaviours. There are limited data on the prevalence and correlates of cigarette smoking among in-school adolescents in Iraq. We aimed to estimate the prevalence of, and assess the socio-demographic correlates of current cigarette smoking among in-school adolescents in Kurdistan region of Iraq.

Methods

Secondary data analysis of the Global Youth Tobacco Survey, conducted in the region of Kurdistan, Iraq in 2006. Logistic regression analysis was conducted to assess the association between current cigarette smoking and explanatory variables.

Results

One thousand nine hundred eighty-nine adolescents participated in the Kurdistan-Iraq Global Youth Tobacco Survey. Of these, 58.1% and 41.9% were boys and girls respectively. The overall prevalence of current cigarette smoking was 15.3%; 25.1% and 2.7% in boys and girls respectively. The factors associated with adolescent smoking were: parents' smoking, smoking in closest friends, male gender, having pocket money and perceptions that boys or girls who smoked were attractive.

Conclusion

We suggest that public health interventions aimed to curb adolescent cigarette smoking should be designed, implemented and evaluated with due recognition to the factors that are associated with the habit.
The proinflammatory cytokines IL-2, IL-15 and IL-21 modulate the repertoire of mature human natural killer cell receptors
Authors: de Rham Casimir , Ferrari-Lacraz Sylvie , Jendly Sabrina , Schneiter Gregory , Dayer Jean-Michel , Villard Jean
Published: December 2007

Natural killer (NK) cells play a crucial role in the immune response to micro-organisms and tumours. Recent evidence suggests that NK cells also regulate the adaptive T-cell response and that it might be possible to exploit this ability to eliminate autoreactive T cells in autoimmune disease and alloreactive T cells in transplantation. Mature NK cells consist of a highly diverse population of cells that expresses different receptors to facilitate recognition of diseased cells and possibly pathogens themselves. Ex vivo culture of NK cells with cytokines such as IL-2 and IL-15 is an approach that permits significant expansion of the NK cell subpopulations, which are likely to have potent antitumour, antiviral, or immunomodulatory effects in autoimmunity. Our data indicate that the addition of IL-21 has a synergistic effect by increasing the numbers of NK cells on a large scale. IL-2 and IL-15 may induce the expression of killer cell immunoglobulin-like receptors (KIRs) in KIR-negative populations, the c-lectin receptor NKG2D and the natural cytotoxic receptor NKp44. The addition of IL-21 to IL-15 or IL-2 can modify the pattern of the KIR receptors and inhibit NKp44 expression by reducing the expression of the adaptor DAP-12. IL-21 also preserved the production of interferon-γ and enhanced the cytotoxic properties of NK cells. Our findings indicate that the proinflammatory cytokines IL-2, IL-15 and IL-21 can modify the peripheral repertoire of NK cells. These properties may be used to endow subpopulations of NK cells with specific phenotypes, which may be used in ex vivo cellular immunotherapy strategies.
Combined Use of Clinical and Pathologic Staging Variables to Define Outcomes for Breast Cancer Patients Treated With Neoadjuvant Therapy
Authors: Jeruss Jacqueline S. , Mittendorf Elizabeth A. , Tucker Susan L. , Gonzalez-Angulo Ana M. , Buchholz Thomas A. , Sahin Aysegul A. , Cormier Janice N. , Buzdar Aman U. , Hortobagyi Gabriel N. , Hunt Kelly K.
Published: December 2007

Purpose

Neoadjuvant chemotherapy is being used with increasing frequency for operable breast cancer. We hypothesized that by using clinical and pathologic staging parameters, in conjunction with biologic tumor markers, a novel means of determining prognosis for patients treated with neoadjuvant chemotherapy could be facilitated.

Patients and Methods

A prospective database of patients treated with neoadjuvant chemotherapy from 1997 to 2003 was reviewed, and 932 patients meeting inclusion criteria were identified. Clinical and pathologic tumor characteristics, treatment regimens, and patient outcomes were recorded. Cox proportional hazards models were used to create two prognostic scoring systems. American Joint Committee on Cancer (AJCC) clinical and pathologic staging parameters and biologic tumor markers were investigated to devise the scoring systems.

Results

Median follow-up time was 5 years (range, 0.4 to 9.4 years). Five-year disease-specific survival rate was 96% for patients who experienced a pathologic complete response (pCR; n = 130) compared with 87% for patients who did not have a pCR (n = 802; P = .001). Two scoring systems, based on summing binary indicators for clinical substages ≥ IIB and ≥ IIIB, pathologic substages ≥ ypIIA and ≥ ypIIIC, negative estrogen receptor status, and grade 3 pathology, were devised to predict 5-year patient outcomes. These scoring systems facilitated separation of the study population into more refined subgroups by outcome than the current AJCC staging system.

Conclusion

The scoring systems derived in this work provide a novel means for evaluating prognosis after neoadjuvant therapy. Future work will focus on prospective validation of these scoring systems and refinement of the scoring systems through addition of new biologic markers.
Stem-Cell Transplantation for Multiple Myeloma in the Era of Novel Drugs
Authors: Bensinger William
Published: December 2007

The treatment of multiple myeloma (MM) is changing rapidly. During the last 10 years, higher rates of complete response (CR) and prolonged progression-free and overall survival have been seen with high-dose chemotherapy plus autologous stem-cell transplantation (HDT-ASCT). Achievement of CR and good partial response have been shown to be key prognostic factors for prolonged survival, with eradication of minimal residual disease seeming crucial to long-term disease-free survival. Until recently, high rates of CR and other major responses were primarily seen with HDT-ASCT, but insights into the biology of MM have led to the development and approval of new drugs with significant activity, and new induction regimens based on these novel agents are offering improved responses. Thalidomide, bortezomib, and lenalidomide have been combined with corticosteroids, alkylators, and anthracyclines in front-line MM treatment. Phase II studies have indicated that high rates of response and CR may be achieved. The substantial activity seen with these new drug combinations has prompted a re-examination of the role of SCT in MM treatment. Will achievement of major responses with these new regimens translate into improved survival after consolidation with transplantation? Will these improved induction regimens reduce the need for tandem transplantation, or does achievement of CR obviate the need for front-line transplantation altogether? To help address these questions, randomized trials are needed, as well as tests with improved sensitivity to better define depth of remission.
Photodissociation Mass Spectrometry of Trinuclear Carbonyl Clusters M3(CO)12 (M = Fe, Ru, Os)
Authors: Chen Hong , Tang Zi-Chao , Huang Rong-Bin , Zheng Lan-Sun
Published: December 2007

Photodissociation of trinuclear carbonyl cluster compounds of Fe, Ru and Os was studied by recording the mass spectra produced from laser ablation of the cluster compounds. Under the experimental conditions, dissociation of the cluster compounds is very extensive, but the dissociation pathway of the osmium cluster is different from those of the iron and ruthenium clusters. The iron and ruthenium clusters not only lost their carbonyl ligands, but their cluster cores were also fragmented. As the osmium cluster dissociated, it ejected three pairs of oxygen atoms, in sequence, before losing the carbonyl ligands, but the trinuclear osmium core did not fragment. This specific dissociation scheme of the osmium cluster reveals its special structural stability. Not only does it have stronger metal-metal bonds, but also a relatively stable coordination bond formed between osmium and carbonyl ligands. In addition, different distributions of positive and negative fragment ions were observed in the experiment. This difference is interpreted as the result of different stabilities of their electronic structures.
Electrospray Studies of a Water Soluble Platinum (II) Phosphine Complex, Chlorotris(1,3,5-Triaza-7-Phosphaadamantane)Platinum (II) Chloride (TPA)3PtCl2
Authors: Fisher Keith J. , Dance Ian G. , Willett Gary D. , Zhang Rui , Alyea Elmer C.
Published: December 2007

The positive- and negative-ion electrospray spectra of methanolic solutions of a water-soluble platinum (II) phosphine complex, chlorotris(1,3,5-triaza-7-phosphaadamantane)platinum (II) chloride, have been shown to contain a series of platinum (II) cations and anions. Mono-platinum ions such as [Pt(TPA)3Cl]+ and [Pt(TPA)2Cl2]Cl− (TPA = 1,3,5-triaza-7-phosphaadamantane) were the most abundant ions but poly-platinum ions were also observed. The ions have been subjected to two different dissociation experiments and the results for skimmer and on-resonance collision-induced dissociations compared. Substitution reactions such as halide exchange and phosphine exchange have been monitored in solution. The gas-phase reactions of hydrogen sulfide with selected ions have been studied.
The Unimolecular Loss of HF by Simple Inorganic Ions: A Computational Dynamic Reaction Path Study
Authors: Aschi Massimiliano , Grandinetti Felice
Published: December 2007

The metastable dissociations of a series of simple inorganic gaseous ions of general formula (H,F,M)+, including NF3H+ (M = NF2), N2F2H+ (M = FN2), F2NOH2+ (M = FNOH) and FNOH+ (M = NO) have been investigated using classical dynamics in order to rationalise their mass-analysed ion kinetic energy (MIKE) spectra which, from earlier experimental studies, showed the systematic loss of neutral hydrofluoric acid, HF, accompanied by a fairly large release of translational energy ( T). All the simulations were initiated in correspondence of the transition structures involved in the above decompositions and expanded on the related Hartree–Fock potential energy surfaces, calculated “on the fly” during the evolution of the trajectories according to the Dynamic Reaction Path methodology. The initial associated momenta were deduced by performing a standard kinetic analysis of the above dissociations taking into account the specific features of the MIKE experiments. For all the above ions, the resulting computed Ts are in reasonable agreement with the experimental values. In addition, from a more accurate analysis of the trajectories, it could be possible to appreciate qualitatively both the specific role of the internal degrees of freedom of the decomposing ions and the dynamic and energetic influence of the HF–M+ ion–neutral complex located between the dissociation products and the tight transition structure involved in the above decompositions.
Rearrangement and Loss of Bromine Radical and CO from Some Bromobenzyl Alcohols following Electron Ionisation
Authors: Kubišta Jiří , Hanuš Vladimír , Havlíček Libor , Hanuš Jan , Halada Petr , Kuzma Marek
Published: December 2007

The electron ionisation spectra of bromine-containing derivatives of benzyl alcohol are often dominated by ions which do not contain bromine. We use the experimental data on a series of selected bromobenzyl alcohols to elucidate the easy loss of bromine atoms. In this process, arene-bonded bromines are displaced by hydrogens which originate from the benzyl group. Thus, we conclude that this reaction occurs during the “hydrogen ring-walk”. The suggested reaction mechanism and structures of intermediates, which can be considered, are discussed and graphically illustrated.
Exchange of Cl+ between Lone-Pair Donors and π-Donors: A Computational Study
Authors: Sølling Theis I. , Radom Leo
Published: December 2007

The chemistry of mono-adducts ([Cl–X]+) between Cl+ and a Lewis base (X = NH3, H2O, HF, PH3, H2S or HCl) has been investigated using ab initio molecular orbital calculations at the G2 level. The reactions of such mono-adducts with additional Lewis bases (Y) are found to give [Y–Cl]+ plus X, generally without an intermediate barrier, via a bis-adduct [Y–Cl–X]+. The binding energies of the bis-adduct and the reaction energies are related to the donor properties of the Lewis bases. The reactions between the mono-adducts [Cl–X]+ and the π-donors ethylene and acetylene yield chloriranium and chlorirenium ions, respectively. These reactions proceed via complexes that resemble either the reactants or products depending on the sign of the reaction energy, the latter in turn being determined by the donor ability of the Lewis base. Results for the chlorine systems are compared with those for the corresponding phosphorus systems investigated previously.
An Electrospray Ionization Fourier Transform Ion Cyclotron Resonance Mass Spectrometry Study of 1,6-Methano[60]Fullerene-61,61-Dicarboxylic Acid
Authors: Zhang Rui , Fisher Keith J. , Smith Derek R. , Willett Gary D. , Peel J. Barrie , Gan Liangbing , Shi Yaru , Gao Zhen
Published: December 2007

1,6-Methano[60]fullerene-61,61-dicarboxylic acid was studied by electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry. The deprotonated molecule, C60C(COOH)COO−, and the decarboxylated molecular anion C60CHCOO− were observed. Gas-phase ion–molecule reactions occurred when the ion accumulation time in an external rf/dc hexapole ion trap was extended. Cluster ions of the type [C60CHCOOH] n[C60CHCOO]− ( n = 1–2) were observed. Multiply-charged anions were observed for the dimer [C60CHCOOH][C60CHCOO]−. Collision-induced dissociation in the ion cyclotron resonance cell showed that C60C(COOH)COO− dissociated through the loss of two CO2 groups, with further fragmentation to produce C60−. A similar fragmentation pathway was also observed with capillary/skimmer collision-induced dissociation during the electrospray process. Semi-empirical calculations using the AM1 approximation with the MOPAC program have been performed on most of the neutral and ionic species related to this compound. Energy differences and charge distributions have been obtained for the possible geometry structures for these species.
Decarboxylation of Carnitine and α-Cyano-4-Hydroxycinnamic Acid under Particle Bombardment
Authors: Bourcier Sophie , Hoppilliard Yannik , Pechiné Jean Marie , Perez Felix
Published: December 2007

Protonated carnitine and α-cyano-4-hydroxycinnamic acid were formed by laser photon irradiation, by MeV-ion bombardment and by electrospray. The spontaneous fragmentations of protonated molecules formed upon particle bombardment are compared with the decompositions induced by low- and high-energy collisions of molecules protonated by electrospray. The determination of fragmentation mechanisms was achieved using labelled compounds and by means of ab initio calculations. The most prominent fragmentation of protonated molecules formed under particle bombardment is an unexpected loss of carbon dioxide. More classical processes dominate the decomposition induced by collisions of electrosprayed species: loss of trimethylamine and 4-hydroxybutyrolactone from protonated carnitine, loss of water from protonated cinnamic acid but no loss of CO2. Decarboxylation occurring before or concomitant with protonation is proposed to interpret these results.
Characterization of Oligosaccharides of the Lactosamine Series Derived from Keratan Sulfates by Tandem Mass Spectrometry
Authors: Kubota Masayuki , Yoshida Keiichi , Tawada Akira , Ohashi Mamoru
Published: December 2007

Positive- and negative-ion fast-atom bombardment tandem mass spectrometry with collision-induced dissociation (FAB-CID-MS/MS) has been used in the characterization of di-and tetra-saccharides of the lactosamine series from keratan sulfates. FAB-CID-MS/MS of Galβ1-4GlcNAc (L1) exhibited strong fragment ions originating from ring cleavage at the reducing-terminal sugar moiety together with glycosidic bond-cleavage ions, whereas GlcNAcβ1-3Gal (K1) showed strong glycosidic bond-cleavage ions but no ring-cleavage ions. A series of ring-cleavage fragment ions was observed with members of the L-series which have free hydroxyl groups at the C1 and C3 positions. CID-MS/MS spectra of the [M + Na – SO3]+ ion ( m/z 406) from L2 and the [M + Na − 2SO3]+ ion ( m/z 406) from L4 were almost identical with the CID-MS/MS spectrum of the [M + Na]+ ion ( m/z 406) from L1, which indicated that the sugar skeletons of L2 and L4 are the same as that of L1. On the other hand, the CID-MS/MS spectrum of the [M + Na – SO3]+ ion ( m/z 508) from L4 did not resemble that of the [M + Na]+ ion ( m/z 508) from L2. The former showed peaks that were additional to the peaks in the latter. Since these extra peaks were accounted for on the basis of the structure of L3 [Galβ1(6S)-4GlcNAc, S = sulfate], the in-source loss of sulfate groups by ester exchange upon FAB ionization takes place in a dual manner; one reaction at the non-reducing terminal sugar to give L2 and the other at the reducing-terminal sugar to give L3. The CID-MS/MS spectra were characteristic for the tetrasaccharides L1-L1, L2-L2 and L4-L4 while in-source fragmentation confirms the component disaccharides of each tetrasaccharide. The structure of a tetrasaccharide trisulfate was confirmed as L2–L4 and not L4–L2 by CID-MS/MS. Negative-ion FAB-CID-MS/MS spectra of the sulfated di-and tetra-saccharides showed a pattern similar to that of the positive-ion spectra. Subtraction of the CID-MS/MS spectrum of the [M – H]− ion of L2 [Galβ1-4GlcNAc(6S)] from that of the [M – H – SO3]− ion of L4 [Gal(6S)β1-4GlcNAc(6S)] gave several specific ions whose origins were nicely explained on the basis of the structure of L3. The structure of a pentasaccharide consisting of N-acetylneuraminic acid and a tetrasaccharide trisulfate was confirmed, on the basis of FAB-CID-MS/MS, as NeuNAcα2-6L2-L4.
Gas-Phase Ion Mobility Studies of Amines and Polyether/Amine Complexes Using Tandem Quadrupole Ion Trap/Ion Mobility Spectrometry
Authors: Creaser Colin S. , Griffiths John R. , Stockton Brian M.
Published: December 2007

The gas-phase positive ion mobility spectra of isomeric amines and polyether/amine complexes have been measured using a tandem quadrupole ion trap/ion mobility spectrometer. Ion mobilities of isomeric amines in helium, determined relative to benzene at pressures in the range 1–2 Torr, vary with the structure of the amine. The ability of quadrupole ion trap/ion mobility spectrometry to differentiate between a pharmacologically-active substance and an associated isomeric amine is demonstrated. Non-covalent complexes of cyclic and acyclic polyethers with protonated amines were generated by ion/molecule reactions in the ion trap and analysed by ion mobility spectrometry. The ion mobilities in helium may be interpreted in terms of the preferred conformations for these complexes. The use of polyether hosts as shift compounds for enhancing the relative mobilities of small amine guest ions is proposed.
Combination of Time-of-Flight Mass Analysers with Magnetic-Sector Instruments: In-Line and Perpendicular Arrangements. Applications to Poly(Ethylene Glycol) with Long-Chain end Groups
Authors: Botrill Andrew R. , Giannakopulos Anastassios E. , Millichope Allen , Lee Ken S. , Derrick Peter J.
Published: December 2007

High-energy collision-induced dissociation has been shown to provide extensive and detailed structural information on poly(ethylene glycol) with palmitoyl end-groups. Fragmentation within the end-groups provides direct information on their structures. Both in-line time-of-flight (TOF) and orthogonal TOF have been used for the measurement of fragment ions. Use of TOF as the second stage of mass spectrometry has facilitated exploitation of the pulsed method of ionisation matrix-assisted laser desorption/ionisation (MALDI). The orthogonal TOF instrument is used with a liquid secondary-ion mass spectrometry source. The laboratory-frame collision energies were different for in-line and orthogonal TOF, being 8–12 keV in the former and 800 eV in the latter. The tandem mass spectra were similar for the in-line experiment with either He or Xe collision gas and the orthogonal experiment with Xe. Mechanisms proposed for the fragmentations involve homolytic cleavage (C–H and backbone bonds) and invoke non-ergodicity.
The Analysis of Conducting Polymers by Electrospray Fourier Transform Mass Spectrometry. Part I: Ionene Polymers
Authors: Dolan Anthony R. , Maziarz E. Peter , Wood Troy D.
Published: December 2007

The analysis of synthetic 6-2, 6-3 and 6-4 ionene polymers by electrospray ionization Fourier transform mass spectrometry (ESIFTMS) is reported here. This is the first in a series of papers on the analysis of conducting polymers utilizing soft ionization techniques, thus allowing for the analysis of intact molecular ions. The syntheses of these individual polymers result in a variety of compounds with different molecular structures which are related to the normal linear ionene polymer. While the mechanisms by which the 6-2 and the 6-3 ionene polymers are synthesized are very similar, the synthesis of 6-4 ionene proceeds differently. In addition, the presence of a gas-phase bromide ion salt-bridged to the backbone of the polymer chain is observed in the resulting mass spectra, as well as the possibility of intramolecular cyclization. The latter has been proposed previously. This cyclization process becomes more possible as the number of methylene groups in the linking chain increases. Finally, we observed that the presence of a bromide ion in the sample helped the interpretation of sustained off-resonance irradiation collisionally-activated dissociation (SORI-CAD). Based on the isotopic pattern provided by the halogens, a “built-in” label which can be traced from the fragment ions back to the parent ion peak is found to be useful in structural assignments.
Sequential Dissociation Kinetics and Fragment Distribution of Cluster Ions
Authors: Huang Rong-Bin , Chen Hong , Zhang Qiang , Zheng Lan-Sun
Published: December 2007

A sequential fragmentation mechanism for production of cluster ions is explored. Based on the mechanism, the kinetic equations were built and analytically solved with and without the constant rate coefficient assumption. Furthermore, the probability of deactivation of the cluster ions was considered, and the kinetic equation with this consideration was also analytically solved. The solutions are able to account for the features of recorded size distribution and magic numbers of C+60 and other cluster ions. The range of time window observing the evaluative yield populations of sequential loss mechanism can also be estimated.
Mass Spectra of Iso-Cinchona- and Halogenated Cinchona Alkaloids
Authors: Bartók Tibor , Felföldi Károly , Szöllösi György , Bartók Mihály , Dega-Szafran Zofia , Thiel Jacek
Published: December 2007

The electron impact ionisation (EI) and electrospray ionisation (ESI) mass spectra using in-source collision-induced dissociation of nine different cinchona alkaloid derivatives [iso-cinchona alkaloids (ethereal isomers) and 10-Br(Cl) containing cinchona compounds] have been studied. In the case of the EI method for iso-cinchona alkaloids the observed fragmentation directions are as follows: isomerisation of the cyclic ethers to the corresponding C9 ketone, the formation of [M − 15]+, [M − 29]+ and [M − 57]+ fragments as a result of the loss of methyl, ethyl and butyl radicals, and the cleavage of the C8–C9 bond. The fragmentation of the compounds containing C10–Br(Cl) bonds started with the scission of this bond. The primary bond rupture is followed by the fragmentation of the primary product into two parts across the C8–C9 bond. In the case of the ESI method at low capillary exit voltage only the peak of the protonated molecule ([M + H]+), and in a significantly lower abundance, the peak of the [M + 2H]2+ ion can be observed. Increasing the capillary exit voltage causes fragmentation to occur. For iso-cinchona alkaloids the main direction is the cleavage of C8–C9 bond. For the C10–Br(Cl) compounds, the primary fragmentations are the cleavage of the C9–O and C10–Br(Cl) bonds. Fragmentation pathways are discussed.
Instrumentation of Kinetic Energy-Resolved Surface-Induced Dissociation in Fourier Transform Mass Spectrometry
Authors: Rakov V. Sergey , Futrell Jean H. , Denisov Edward V. , Nikolaev Eugene N.
Published: December 2007

A Bruker 7 T Fourier transform (FT) mass spectrometer fitted with electron impact (EI) and electrospray ionization (ESI) external ion sources has been modified for surface-induced dissociation (SID) studies utilizing a self-assembled monolayer (SAM) of CF3(CF2)9C2H4SH alkanethiolate chemisorbed on gold. Operational aspects of ion sources, intermediate hexapole ion storage, time-of-flight function of the ion optics and cell trapping mechanisms are discussed for both primary and secondary ions. Different methods of ion trapping in the FT ion cyclotron resonance cell were analyzed theoretically and dynamic voltage trapping (DVT) was chosen as the most suitable. Direct measurements of primary (short time scale) and secondary (delayed) SID fragmentation and kinetic energy distributions of the SID fragments illustrate the capabilities of the instrument as a research tool for investigating SID kinetics. SID of small molecules and model peptides was investigated over a moderate collision energy range and the ion population was sampled at various decomposition delay times. Kinetic energy distributions of SID fragment ions were measured and shown to be quite low over the range of energies investigated. Most of the primary ion kinetic energy is dissipated into surface excitation and internal energy of ions recoiled from the surface.
Characterization of the N-Linked Glycan of Recombinantly-Expressed Corticotropin Releasing Factor Binding Protein
Authors: Sutton Steve W. , Akhtar Mateen , Schmidt Karsten , Fischer Wolfgang H. , Vale Wylie W. , Craig A. Grey
Published: December 2007

The N-linked glycan present on corticotropin releasing factor binding protein (CRFBP) recombinantly expressed in CHO cells has been characterized using a variety of techniques including sequential hydrolysis with specific exoglycosidases monitored with reversed-phase high performance liquid chromatography (RP-HPLC), matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) and electrospray ionization mass spectrometry (ES-MS). Determining the intact glycan mass and comparing possible glycan compositions with entries in the Complex Carbohydrate Database facilitated the choice of enzymes. Tandem mass spectrometry (MS/MS) was used to confirm the structure of the glycan. Using this approach, complementary information could be obtained through specific glycosidase reactions monitored with MS and MS n fragmentation of the intact or enzymatically-modified glycopeptides. No evidence was found for the presence of sites of O-linked glycosylation. In addition, to understand better the role of the glycan on CRFBP, we characterized the in vitro binding affinity of a mutant non-glycosylated [Gln180] CRFBP and an enzymatically deglycosylated form of CRFBP to human corticotropin releasing factor (hCRF).
The Effect of Phenyl Substitution on the Thermochemistry of Gas-Phase Ions and Their Neutral Counterparts
Authors: Aubry Christiane , Holmes John L.
Published: December 2007

The available data for the heats of formation of phenyl-substituted organics have been critically evaluated. Phenyl substitution is always thermochemically destabilizing in that Δ fH0[R–C6H5] – Δ fH0[R–H] is a positive quantity. The magnitude of the effect in neutrals depends on the substitution site, e.g. from + 79 kJ mol−1 for HCOR or HCCR to + 155 kJ mol−1 for RCO2H. Multiple phenyl substitution (where possible) at the same site is generally simply additive. For the corresponding cationic species, the first phenyl substitution is stabilizing when the ionization energy of the substrate is lowered thereby and for even-electron ions resonance-stabilization energies may also come into play. Additional phenyl substitution at the same site is, however, always destabilizing. Phenyl substitutions were compared with vinyl substitution: for neutral species the effects are similar, whereas for even-electron ions, multiple vinyl substitution is only weakly stabilizing or destabilizing.
Location of the Negative Charge(s) on the Backbone of Single-Stranded Deoxyribonucleic Acid in the Gas Phase
Authors: Favre Amélie , Gonnet Florence , Tabet Jean-Claude
Published: December 2007

Multiply-deprotonated, single-strand products of mono and heteronucleotides, prepared in a nanospray external source coupled to an ion trap mass spectrometer, were studied under low-energy collision conditions. Fragmentations enabled the negative charge carried by the selected anions to be located. Comparison of multi-deprotonated 5′-dephosphorylated and 5′-phosphorylated nucleotides showed that the former led to competitive BH and B− losses via isomerization into ion–dipole complexes prior to dissociation, which contrasts with the 5′-phosphorylated nucleoside yielding the competitive HPO3 and nucleobase eliminations. The proposed mechanisms are discussed according to: (i) the charge state of the precursor studied and (ii) the thermochemical gas-phase properties such as the relative acidities of neutrals, which formally constitute the ion–dipole. The formation of various fragment ions from doubly- and triply-deprotonated precursor ions enabled the negative charge to be located, specifically at the terminal phosphodiester groups of the single-strand oligonucleotides. The potential energy is, therefore, minimal for distant charged phosphorylated groups. These findings suggest that a specific conformation is favored in order to minimize coulomb repulsion during the desolvation process. This hypothesis is consistent with the assumed behavior of triply- and quadruply-deprotonated, mono-cationized oligonucleotides, which involves a specific location of the sodium cation, as previously shown.
Biological Detection Using Self-Ionization Optimization in an Ion Trap Mass Spectrometer
Authors: Wind F.L. , Stephan P. , Tabet J.C.
Published: December 2007

For a few years now, mass spectrometry techniques have contributed significantly to the investigation of biomaterials. Characterization of active molecules from biological organisms is one of the areas in which mass spectrometry and tandem mass spectrometry have been applied frequently. Various configurations of mass spectrometry have been used in bacterial taxonomy for the preferential detection of chemical taxonomic markers. Our purpose was to carry out a preliminary study and exploration of a new taxonomic profiling approach: self-ionization for MH+ generation followed by structural determination by collision-induced dissociation investigation. Fatty acid methyl ester profiles from electron impact (EI) mass spectrum analysis have been chosen as specific biomarkers to differentiate different samples. The fragmentation pathways of biological material in the ion trap mass spectrometer are the result of the co-existence of different ionization processes: EI ionization and self-ionization due to the high efficiency of large molecule reactions induced from EI fragment ions. The corresponding neutrals of the ions have a relatively low basicity compared to the analyzed substrate. This will be discussed further.
Accounting for Multiply-Charged Ions in Quantitative Analyses of Solid Materials Using a Laser-Plasma Source
Authors: Kouznetsov Grigori B. , Bikovskii Yurii A. , Gladkov Vladimir P.
Published: December 2007

This paper investigates the relative output of multiply-charged ions created in a laser-plasma source. It shows that output of ions depends on the mode of the laser. Accounting for multiply-charged ions in the analysis reduces errors in the measurements. This method is applied to the design of a new technique for the quantitative analysis of materials.
Estimation of a Nucleoside Proton Affinity Scale from Dissociations of Hydrogen-Bound Heterodimer Constituted with Amino Acid Partners
Authors: Alves S. , Fournier F. , Tabet J.-C. , Quelquejeu M. , Valery J.M.
Published: December 2007

Nucleoside proton affinity was determined using Cooks' kinetic method. An ion trap mass spectrometer coupled with an external electrospray source was used to form proton-bound homo- and heterodimers from modified uridines and amino acids at low effective temperature. The experimental proton affinity ( PA) values obtained show the effects of structural changes in nucleosides on PA values (i.e. U < dU and 5IdU < dU < dT). The calculated values are consistent with those reported by tandem sector instruments. In this way, an hypothesis on the interaction site of the heterodimers is proposed: the amino groups are likely to interact with the proton (in the dimer) as expected from its solution behavior.
Time-of-Flight Analysers with Sector Fields: Advances and Prospects
Authors: Sysoev A.A.
Published: December 2007

This paper is devoted to the problem of using time-of-flight mass spectrometers with axially-symmetric electrostatic sector fields. The general theory of these analysers takes into account both magnetic and electrostatic fields. Time-of-flight mass analysers with electrostatic fields are considered as a particular case. The conditions of triple focusing are given and formulae for their calculation are presented. Some calculated characteristic data for such analysers demonstrate their capabilities. Results of analyser testing are also presented. A resolution of 1000 is demonstrated; this resolution can be increased up to 10,000 by correction of time aberrations.
Novel Linac II Electrode Geometry for Creating An Axial Field in a Multipole Ion Guide
Authors: Loboda Alexander , Krutchinsky Andrew , Loboda Olga , McNabb James , Spicer Victor , Ens Werner , Standing Kenneth
Published: December 2007

Tandem instruments, such as triple-quadrupole or quadrupole-time-of-flight mass spectrometers, often use collisional damping ion guides for the purpose of cooling and focusing the primary ion beam, or as a collision cell for tandem mass spectrometry experiments. A small axial field to reduce the ion residence time in such devices can give considerable improvements in performance. Reduction of the residence time reduces adduct formation caused by unwanted gas-phase reactions and allows multiple reaction monitoring (MRM) and some other types of scan to be carried out more rapidly without the risk of reaction cross-talk. Here we propose a novel electrode arrangement for creation of a suitable axial field in a multipole ion guide without significantly reducing the m/z window. As an example, a second set of four electrodes is added to an existing quadrupole collision cell. The same DC potential is applied to all four extra electrodes, which are shaped in the longitudinal direction to create a suitable axial field inside the device. The potential of these electrodes and the DC bias of the main rods determine the axial field strength. The idea was tested on a modified quadrupole collision cell of a MALDI-QqTOF instrument and experimental results are presented here, as well as a simplified theory of operation.
Content Validation of the Organizational Climate for Research Integrity (OCRI) Survey
Authors: Thrush Carol R. , Putten Jim Vander , Rapp Carla Gene , Pearson L. Carolyn , Berry Katherine Simms , O'Sullivan Patricia S.
Published: December 2007

The purpose of this study was to develop and establish content validity of an instrument designed to measure the organizational climate for research integrity in academic health centers. Twenty-seven research integrity scholars and administrators evaluated 64 survey items for relevance and clarity, as well as overall comprehensiveness of the constructs that are measured (organizational inputs, structures, processes and outcomes). Both quantitative and qualitative methods were used, particularly content validity indices (CVI) and analyses of respondents' comments. The content validity index for the overall survey was initially high (CVI = .83) and improved (CVI = .90) when 17 marginal-to-poor items were removed. This study resulted in the Organizational Climate for Research Integrity (OCRI) survey, a 43-item fixed-response survey with established content validity.
Assessment of Children's Health-Related Quality of Life in the United States With a Multidimensional Index
Authors: Simon Alan E. , Chan Kitty S. , Forrest Christopher B.
Published: December 2007

OBJECTIVE. Using nationally representative data, we examined biological, medical system, and sociodemographic factors that are associated with health-related quality of life as measured by a multidimensional index that accounts for a wide range of child health domains.

METHODS. Children aged ≥6 years (N = 69031) were drawn from the 2003/2004 National Survey of Children's Health. A random 25% sample was used to create a 12-item index of health-related quality of life with a range of 0 to 100, based on the conceptual framework of the Child Health and Illness Profile. Bivariate and multivariable regression analyses were conducted to identify the unadjusted and independent associations of key biological, medical system, and sociodemographic variables with health-related quality of life.

RESULTS. The index mean was 72.3 (SD: 14.5), median value was 73.7, and range was 11.1 to 99.9. Only 0.2% of children had a score at the ceiling. In multivariable regression analysis, the following variables were independently associated with lower health-related quality of life: biological factors (greater disease burden, severe asthma, and overweight status); medical system factors (unmet medical needs, lack of a regular health care provider, Medicaid insurance, or being uninsured previously during the year); and sociodemographic factors (older age groups, lower family education, single-mother family, having a smoker in the household, black race, and poverty).

CONCLUSIONS. Health-related quality of life in the United States is poorest for children and youth in lower socioeconomic status groups, those with access barriers, adolescents compared with children, and individuals with medical conditions. A multidimensional health-related quality-of-life index is an alternative to conventional measures (eg, mortality) for national monitoring of child health.
Quality and quantity of obstetrical care in Baross Street Department of Obstetrics and Gynecology between 1990 and 2006
Authors: Nagy Gyula Richárd , Papp Zoltán
Published: December 2007

Célkitűzés és módszer:
A szerzők a Semmelweis Egyetem I. Szülészeti és Nőgyógyászati Klinikáján 1990. január 1. és 2006. december 31. között a terhesség 24. és 42. hete között befejeződött 48 794 terhesség adatait elemezték olyan számítógépes nyilvántartási rendszerük adataira támaszkodva, mely a szülészeti, genetikai és neonatológiai ellátás komplexitását tükrözi.
Eredmények:
A szülésszám az adott 17 évben folyamatosan emelkedett, 1990-ben 2299, míg 2006-ban 3861 szülést regisztráltak. A korai neonatalis mortalitás fokozatosan csökkent (1990-ben 22/1000 élveszületés, 2006-ban 6/1000 élveszületés). Ha nem vesszük figyelembe az 1000 g súly alatt meghalt, az intézeten kívül intrauterin elhalt és a malformatio miatti szülésindukciók következtében születetteket, a perinatalis mortalitás igen alacsony, az utóbbi 7 évben 6/1000 szülés alatti, 2004-ben 2,8/1000 szülés, 2005-ben és 2006-ban pedig 1,8–1,9/1000 szülés! A neonatalis és csecsemőkori mortalitás adataiban is jelentős csökkenés tapasztalható. A császármetszések száma a vizsgált időszakban fokozatosan emelkedett; gyakoriságuk 1990–1991-ben 15–20%, az utóbbi években pedig 35% körül mozog. A főbb javallatok között szerepel az előzetes császármetszés utáni állapot, a (fenyegető) magzati hypoxia/acidosis, fájásgyengeség/elhúzódó szülés, relatív téraránytalanság, többes terhesség, hipertónia/praeeclampsia/HELLP-szindróma, medencevégű fekvés.
Következtetések:
A progresszív betegellátás következtében a klinikán a szülések kb. ötödrésze koraszülés, valamint számos súlyos terhespatológiai eset fordult elő, ennek ellenére a perinatalis statisztikai mutatókban – az utóbbi 17 év adatait elemezve – kedvező változások mutatkoznak, jelezvén a szülészeti és neonatológiai ellátás folyamatos szakmai fejlődését.
Cerebral Complications of Diabetes Mellitus
Authors: Aszalós Zsuzsa
Published: December 2007

A WHO adatai szerint a világon jelenleg több mint 180 millióan szenvednek diabetes mellitusban, és ez a szám 15 éven belül megduplázódik. Az agy működése a folyamatos glükózellátás függvénye, hypoglykaemiában a homeostasis megtartására irányuló ellenregulációs hormonok (glukagon, adrenalin, növekedési hormon, kortizol) termelődése fokozódik, a szimpatikus idegrendszer aktiválódik, neuroglykopenia tünetei jelennek meg. Az alarmírozó, az életet aktuálisan veszélyeztető állapotnak azonban még ismétlődés esetén sem olyan kifejezettek a hosszú távú szövődményei, mint a hyperglykaemiának. A hyperglykaemiára adott aktív neurális válasz a génexpresszió és génműködés megváltozása. A kezdetben adaptív, hyperosmolalitás elleni lépések a hypothalamicus magnocellularis neurosecretiós sejtek hiperaktivitásához, majd strukturális károsodásához vezetnek. Részben a hippocampalis géntranszkripciós változások állnak a deklaratív memória csökkenése hátterében. A neurológiailag passzív választ a cukorfölösleget elvezető metabolikus kerülőutak jelentik, melyek részben az atherogen, vascularis károsító tényezőkért, részben a szabadgyök-képződésért, leukoencephalopathia és cerebrális atrófia kialakulásáért felelősek, s ezúton okoznak kognitív deficitet. Fiziológiás körülmények között az inzulin neuroprotektív, azonban a perifériás inzulinrezisztenciával korreláló központi idegrendszeri inzulinrezisztencia miatt a protektív hatás csökken, az apoptoticus folyamatok, neurodegeneráció és a következményes kognitív hanyatlás kerül előtérbe. A diabetes mellitus az Alzheimer-kórral számos, még nem tisztázott összefüggést mutat, különösen az APOE-4 gént hordozó diabéteszeseknek nagyobb az esélyük az Alzheimer-kórban való megbetegedésre. Diabetes mellitusban a depresszió prevalenciája megnő, de a depresszió is kockázati tényező diabetes mellitusra nézve. A két kórkép egyidejű fennállása mindkettő kórlefolyását súlyosbítja.
Prediction of Tread Pattern Wear by an Explicit Finite Element Model
Authors: Cho J. C. , Jung B. C.
Published: December 2007

Tread pattern wear is predicted by using an explicit finite element model (FEM) and compared with the indoor drum test results under a set of actual driving conditions. One pattern is used to determine the wear rate equation, which is composed of slip velocity and tangential stress under a single driving condition. Two other patterns with the same size (225/45ZR17) and profile are used to be simulated and compared with the indoor wear test results under the actual driving conditions. As a study on the rubber wear rate equation, trial wear rates are assumed by several constitutive equations and each trial wear rate is integrated along time to yield the total accumulated wear under a selected single cornering condition. The trial constitutive equations are defined by independently varying each exponent of slip velocity and tangential stress. The integrated results are compared with the indoor test results, and the best matching constitutive equation for wear is selected for the following wear simulation of two other patterns under actual driving conditions. Tens of thousands of driving conditions of a tire are categorized into a small number of simplified conditions by a suggested simplification procedure which considers the driving condition frequency and weighting function. Both of these simplified conditions and the original actual conditions are tested on the indoor drum test machines. The two results can be regarded to be in good agreement if the deviation that exists in the data is mainly due to the difference in the test velocity. Therefore, the simplification procedure is justified. By applying the selected wear rate equation and the simplified driving conditions to the explicit FEM simulation, the simulated wear results for the two patterns show good match with the actual indoor wear results.
Primary and secondary limb cellulitis in horses: 44 cases (2000–2006)
Authors: Adam Emma N. , Southwood Louise L.
Published: December 2007

Objective—To determine historical, physical, and microbiologic findings in horses with limb cellulitis and identify factors associated with short- and long-term outcome.

Design—Retrospective case series.

Animals—44 horses with limb cellulitis.

Procedures—Information obtained from medical records included use, history, affected limb, diagnostic procedures, treatment, and short-term outcome. Long-term follow-up information was obtained by means of a telephone survey.

Results—Twenty-four horses had primary cellulitis, and 18 of the 24 (75%) had a hind limb affected. Results of microbiologic culture were positive for all 20 horses with primary cellulitis from which specimens were obtained, with coagulase-positive Staphylococcus spp recovered from 12 of the 20. Short-term survival rate was 67% (16/24) for horses with primary cellulitis; 7 of the 9 horses available for long-term follow-up were being used for their intended use, and 4 had had a recurrence. Results of microbiologic culture were positive for 13 of the 16 (81%) horses with secondary cellulitis from which specimens were obtained. Short-term survival rate for horses with secondary cellulitis was 90% (18/20). Eleven of the 17 horses available for long-term follow-up were being used for their intended use; 2 had had a recurrence.

Conclusions and Clinical Relevance—Results suggested that cellulitis can be a life-threatening condition in horses. Horses that were febrile at admission or that developed laminitis were significantly less likely to survive. The prognosis for return to function was guarded, and recurrence was a potential concern.
Phase II Testing of Sunitinib: The National Cancer Institute of Canada Clinical Trials Group IND Program Trials IND.182–185
Authors: Buckstein R. , Meyer R. M. , Seymour L. , Biagi J. , MacKay H. , Laurie S. , Eisenhauer E.
Published: December 2007

Sunitinib (SU11248) is an orally bioavailable inhibitor that affects the receptor tyrosine kinases involved in tumour proliferation and angiogenesis, including vascular endothelial growth factor (vegf) receptors 1, 2, 3, and platelet-derived growth factor receptors alpha (pdgfra) and beta (pdgfrb). Because angiogenesis is necessary for the growth and metastasis of solid tumours, and vegf is believed to have a pivotal role in that process, sunitinib treatment may have broad-spectrum clinical utility. In the present article, we discuss the biologic and clinical rationales that have recently led the Investigational New Drug Program of the National Cancer Institute of Canada Clinical Trials Group to initiate four phase ii trials testing this agent in the following four different tumour types: relapsed diffuse large cell lymphoma, malignant pleural mesothelioma, locally advanced or metastatic cervical cancer and recurrent epithelial ovarian, fallopian tube, or primary peritoneal carcinoma.
Radiation Oncology: Times of Practice Change
Authors: Freeman Carolyn R. , Podgorsak E. B.
Published: December 2007

Developments in radiotherapy during the past 10–15 years, which have been driven largely by technological advances, have been nothing short of remarkable. Significant advances in tumour imaging, in radiotherapy treatment planning, and in dose delivery techniques have all contributed to improved treatment outcomes and have, in some situations, led to important changes in overall therapeutic approach [...]