bluuebunny/crossref_metadata_2025 huggingface dataset:
Molecular Epidemiology of Tuberculosis: Current Insights
Authors: Mathema Barun , Kurepina Natalia E. , Bifani Pablo J. , Kreiswirth Barry N.
Published: October 2006

Molecular epidemiologic studies of tuberculosis (TB) have focused largely on utilizing molecular techniques to address short- and long-term epidemiologic questions, such as in outbreak investigations and in assessing the global dissemination of strains, respectively. This is done primarily by examining the extent of genetic diversity of clinical strains ofMycobacterium tuberculosis. When molecular methods are used in conjunction with classical epidemiology, their utility for TB control has been realized. For instance, molecular epidemiologic studies have added much-needed accuracy and precision in describing transmission dynamics, and they have facilitated investigation of previously unresolved issues, such as estimates of recent-versus-reactive disease and the extent of exogenous reinfection. In addition, there is mounting evidence to suggest that specific strains ofM. tuberculosisbelonging to discrete phylogenetic clusters (lineages) may differ in virulence, pathogenesis, and epidemiologic characteristics, all of which may significantly impact TB control and vaccine development strategies. Here, we review the current methods, concepts, and applications of molecular approaches used to better understand the epidemiology of TB.
Updated Review of Blood Culture Contamination
Authors: Hall Keri K. , Lyman Jason A.
Published: October 2006

Blood culture contamination represents an ongoing source of frustration for clinicians and microbiologists alike. Ambiguous culture results often lead to diagnostic uncertainty in clinical management and are associated with increased health care costs due to unnecessary treatment and testing. A variety of strategies have been investigated and employed to decrease contamination rates. In addition, numerous approaches to increase our ability to distinguish between clinically significant bacteremia and contamination have been explored. In recent years, there has been an increase in the application of computer-based tools to support infection control activities as well as provide clinical decision support related to the management of infectious diseases. Finally, new approaches for estimating bacteremia risk which have the potential to decrease unnecessary blood culture utilization have been developed and evaluated. In this review, we provide an overview of blood culture contamination and describe the potential utility of a variety of approaches to improve both detection and prevention. While it is clear that progress is being made, fundamental challenges remain.
ON q-EXTENSIONS OF MEHTA'S EIGENVECTORS OF THE FINITE FOURIER TRANSFORM
Authors: ATAKISHIYEV NATIG M.
Published: October 2006

Mehta has shown that eigenvectors [Formula: see text] of the finite Fourier transform with the matrix [Formula: see text], 0 ≤ j, k ≤ N-1, can be defined in terms of the classical Hermite functions [Formula: see text] as [Formula: see text], where [Formula: see text]. We argue that the finite Fourier transform [Formula: see text] does actually govern also some q-extensions of Mehta's eigenvectors [Formula: see text], associated with certain well-known orthogonal q-polynomial families. For the pairs of the continuous q-Hermite and q-1-Hermite polynomials, the Rogers–Szegő and Stieltjes–Wigert polynomials, and the discrete q-Hermite polynomials of types I and II such links are explicitly derived.

In the limit when the base q → 1 these q-extensions coincide with Mehta's eigenvectors [Formula: see text], whereas in the continuous limit (i.e. when the parameter N → ∞) they correspond to the classical Fourier integral transforms between the above-mentioned pairs of q-polynomial families.
NON-ABELIAN TENSOR GAUGE FIELDS II
Authors: SAVVIDY GEORGE
Published: October 2006

In recent papers we suggested an infinite-dimensional extension of gauge transformations which includes non-Abelian tensor gauge fields. Extended gauge transformations of non-Abelian tensor gauge fields form a new large group which has a natural geometrical interpretation in terms of extended current algebra associated with compact Lie group. We shall demonstrate that one can construct two infinite series of gauge invariant quadratic forms, so that a linear combination of them comprises the general Lagrangian. The general Lagrangian exhibits enhanced local gauge invariance with double number of gauge parameters and allows to eliminate all negative norm states of the nonsymmetric second-rank tensor gauge field. Therefore it describes two polarizations of helicity-two massless charged tensor gauge boson and the helicity-zero Kalb–Ramond field. The geometrical interpretation of the enhanced gauge symmetry with double number of gauge parameters is not yet known.
THE GROUND STATE OF QUANTUM RINGS IN A MAGNETIC FIELD
Authors: LIU YI-MIN , HUANG GANG-MING , SHI TING-YUN
Published: October 2006

The ground state of semiconductor quantum rings (QRs) in the presence of an external magnetic field B is theoretically analyzed. By numerically diagonalizing the effective-mass Hamiltonian of the QRs, the energy and wavefunction of the ground state are obtained. It is found that the energy oscillates as B increases. The evolution of the angular momentum L0 and the spin S0 of the ground state in accord with B is revealed. We depict the geometric configuration of the ground state via density functions. Based on an analysis of the wavefunction, it is shown that each configuration is accessible only to a specific group of states having specific L0 and S0.
THEORY OF INTERFACE EXCITON WITH A HOLE CONFINED IN A QUANTUM WELL
Authors: THANH NGO VAN , VIET NGUYEN AI
Published: October 2006

We develop a simple model of the interface exciton with an electron strongly confined in the interface plane and a hole confined in the quantum well. The main parameters of the theory are: the distance d between the interface plane and center of the quantum well, and the parameters of quantum well (the half-width a and the height V0). Using the variational method, we obtained the binding energy and effective optical efficiency of this type of interface exciton. This model can be developed to investigate the properties of two-dimensional excitons in coupled quantum well.1
MODELING OF CYCLIC TOPOLOGY IN SCALE-FREE NETWORKS
Authors: KIM HYUN-JOO , CHOI YEON-MU
Published: October 2006

We introduce a growing network model describing the cyclic topology of scale-free networks. In the model, we add new vertices and attach new edges between already existing vertices. The new edges are added by two different processes which is controlled by a parameter p. One is the neighbor attachment process which makes the network become cyclic, and the other is the preferential attachment process which results in the scale-free property of the network. We measure the cyclic coefficient R for various p and find that it linearly depend on p. Also by measuring the distribution of the local cyclic coefficient we survey the change of cyclic topology in the networks for varing p and compare it to the real networks.
SORTING OF MESOSCOPIC PARTICLES DRIVEN THROUGH PERIODIC POTENTIAL LANDSCAPES
Authors: LACASTA A. M. , KHOURY M. , SANCHO J. M. , LINDENBERG KATJA
Published: October 2006

Sorting of colloidal particles of different sizes is of importance in the transport and delivery of such particles in biological, materials science, and other technological contexts. A successful methodology involves the flow of a mixture of particles over designer surfaces presenting a periodic array of traps (optical tweezers) or microfabricated obstacles. The trajectories of the particles over these surfaces deviate from the direction of flow as the particles are attracted (traps) or repelled (obstacles) by the features of the landscape. The deviation of the particles from that of the flow depends on particle size (or on some other particle characteristic) and hence the particles can be sorted according to trajectory direction. On the basis of extensive numerical simulations, we present a unified view of these methodologies and discuss the effects of system parameters such as the magnitude and direction of the flow on the sorting efficacy.
EFFECTS OF SOCIAL CAPITAL ON THE OPPORTUNITY RECOGNITION PROCESS
Authors: PUHAKKA VESA
Published: October 2006

The study hypothesizes that social capital of entrepreneurs enhances their opportunity recognition process. The study investigated metal- and ICT-ventures established in 1998 in three different regions of Finland. The results showed that entrepreneurs when recognizing opportunities have (1) active social interaction to acquire knowledge, to forecast future trends, and to evaluate information and decisions, (2) personal contacts to acquire knowledge and to analyze markets, and (3) cognitively committed relationships to evaluate and understand the information and to enact proactively future trends.
Signaling interactions of rapamycin combined with erlotinib in cervical carcinoma xenografts
Authors: Birle Diana C. , Hedley David W.
Published: October 2006

Clinical trials using rapamycin analogues or HER1/epidermal growth factor receptor (EGFR) inhibitors show that each class of agent has activity against a range of human solid tumors. Because blockade of mitogen-activated protein kinase signaling occurs following HER1/EGFR inhibition in some cell types, we tested the combination of rapamycin and erlotinib in SiHa, Me180, and CaSki human cervical carcinomas xenografts in severe combined immunodeficient mice. In tissue culture, all three cell lines showed decreased phosphorylated S6 ribosomal protein and decreased phosphorylated extracellular signal-regulated kinase (ERK) following treatment with rapamycin and erlotinib, respectively. In SiHa tumors, suppression of phosphorylated S6 was induced by either drug alone, whereas phosphorylated ERK decreased with erlotinib, and enhancement of these effects was obtained with the combination. Continuous treatment of xenografts for 3 weeks led to significant tumor growth delay compared with vehicle control for rapamycin as single agent (P = 0.003) and greater for the combination (P = 0.04 versus rapamycin). Significant antiangiogenic effect was obtained in SiHa xenografts using the drugs together (measured by microvascular density and vascular endothelial growth factor plasma levels) but not for the single agents. Me180 and CaSki xenografts showed significant growth delay with rapamycin but not with erlotinib. Erlotinib treatment resulted in decreased phosphorylated ERK, associated with enhanced suppression of phosphorylated S6 and improved growth delay in Me180 but not in CaSki tumors. These results support the further clinical investigation of rapamycin and EGFR inhibitor combinations in anticancer therapy but highlight the problem of intertumoral heterogeneity in the prediction of in vivo response. [Mol Cancer Ther 2006;5(10):2494–502]
Quantitative analysis of O6-alkylguanine-DNA alkyltransferase in malignant glioma
Authors: Maxwell Jill A. , Johnson Stewart P. , Quinn Jennifer A. , McLendon Roger E. , Ali-Osman Francis , Friedman Allan H. , Herndon James E. , Bierau Katja , Bigley Joseph , Bigner Darell D. , Friedman Henry S.
Published: October 2006

Promoter hypermethylation of the DNA repair protein O6-alkylguanine-DNA alkyltransferase (AGT) has been associated with an enhanced response to chloroethylating and methylating agents in patients with malignant glioma. The purpose of this study was to compare three distinct yet related indices for measuring AGT to determine if these assays could be used interchangeably when AGT status is to be used to guide chemotherapeutic decisions. Real-time methylation-specific PCR (MSP), assessed as the ratio of methylated AGT copies to internal β-actin control, was used to quantitate AGT hypermethylation in 32 glioma samples. Data were compared with AGT enzyme activity as well as immunohistochemical detection of AGT protein from the same samples. Hypermethylation of the AGT promoter was detected in 19 of 31 (61%) samples evaluable by MSP. Low-level AGT, defined as <20% nuclear AGT staining by immunohistochemistry, was found in 10 of 32 samples (31%), whereas 12 of 32 (38%) had low levels of AGT activity. Correlation of immunohistochemistry to AGT activity was statistically significant (P = 0.014) as was the correlation of immunohistochemistry to MSP (P = 0.043), whereas MSP compared with AGT activity (P = 0.246) was not significant. Cross-tabulation of immunohistochemistry and MSP data based on prognostic groups, where good prognosis was represented by an immunohistochemistry of <20% and an MSP ratio >12, showed no significant relationship (P = 0.214), suggesting that one assay cannot be used interchangeably for another. The observed discordance between respective measures of AGT based on prognosis supports further standardization of AGT assays designed to guide therapeutic practice. The data also suggest that consideration be given to the large population of AGT-expressing cells within samples when therapeutic strategies based on tumor methylation are used. [Mol Cancer Ther 2006;5(10):2531–9]
Inhibition of cell growth and nuclear factor-κB activity in pancreatic cancer cell lines by a tylophorine analogue, DCB-3503
Authors: Shiah Her-Shyong , Gao Wenli , Baker David C. , Cheng Yung-Chi
Published: October 2006

A tylophorine analogue, DCB-3503, has been shown to have potent activity against tumor growth in vitro and in vivo, as well as activity in an autoimmune disease model in vivo. This study focuses on investigating the mechanisms responsible for antitumor activity of DCB-3503. The concentrations for inhibiting 50% growth/colony formation ability are 50/162 and 40/149 nmol/L for PANC-1 and HPAC cells, respectively. The growth inhibition effects are associated with DCB-3503-induced reprogramming of tumor cells. DCB-3503 could interfere with cell cycle progression. Several cell cycle regulatory proteins, including cyclin D1, are down-regulated by DCB-3503. Using several different transcription elements coupled with a reporter gene, it was found that the nuclear factor-κB (NF-κB) signaling pathway is the most sensitive pathway mediator affected by DCB-3503. The inhibition of NF-κB activity is dependent on the down-regulation of nuclear phosphorylated p65, a component of the active form of the NF-κB complex. Such a decrease in nuclear phosphorylated p65 can be reversed by a proteosome inhibitor. Furthermore, the activity and protein expression of nuclear IκB kinase α, which is responsible for p65 phosphorylation, is suppressed and down-regulated in cells treated with DCB-3503. In summary, DCB-3503 could affect cell cycle regulatory proteins and is a potent modulator of NF-κB function. It is a potentially useful compound in the management of cancers in which cyclin D1 overexpression and high NF-κB activity play a pivotal role. [Mol Cancer Ther 2006;5(10):2484–93]
Expression of a suicidal gene under control of the human secreted protein acidic and rich in cysteine (SPARC) promoter in tumor or stromal cells led to the inhibition of tumor cell growth
Authors: Lopez María V. , Blanco Patricia , Viale Diego L. , Cafferata Eduardo G. , Carbone Cecilia , Gould David , Chernajovsky Yuti , Podhajcer Osvaldo L.
Published: October 2006

The successful use of transcriptional targeting for cancer therapy depends on the activity of a given promoter inside the malignant cell. Because solid human tumors evolve as a “cross-talk” between the different cell types within the tumor, we hypothesized that targeting the entire tumor mass might have better therapeutic effect. Secreted protein acidic and rich in cysteine (SPARC) is a matricellular protein overexpressed in different human cancers malignant melanomas both in the malignant cells compartment as in the stromal one (fibroblasts and endothelial cells). We have shown that expression of the herpes simplex virus–thymidine kinase (TK) gene driven by the SPARC promoter in combination with ganciclovir inhibited human melanoma cell growth in monolayer as well as in multicellular spheroids. This inhibitory effect was observed both in homotypic spheroids composed of melanoma cells alone as well as in spheroids made of melanoma cells and stromal cells. Expression of the TK gene was also efficient to inhibit the in vivo tumor growth of established melanomas when TK was expressed either by the malignant cells themselves or by coadministered endothelial cells. Our data suggest that the use of therapeutic genes driven by SPARC promoter could be a valuable strategy for cancer therapy aiming to target all the cellular components of the tumor mass. [Mol Cancer Ther 2006;5(10):2503–11]
A urokinase-activated recombinant anthrax toxin is selectively cytotoxic to many human tumor cell types
Authors: Abi-Habib Ralph J. , Singh Ravibhushan , Liu Shihui , Bugge Thomas H. , Leppla Stephen H. , Frankel Arthur E.
Published: October 2006

Urokinase plasminogen activator (uPA) is a tumor-specific protease highly expressed in several types of solid tumors and rarely present on normal cells under physiologic conditions. Due to its high expression on metastatic tumors, several different strategies have been used to target the urokinase system. These have mostly led to tumor growth inhibition rather than tumor regression. A different approach was adopted by replacing the furin activation site on a recombinant anthrax toxin with a urokinase activation site. The resulting toxin, PrAgU2/FP59, was highly potent against tumors both in vitro and in vivo. In this study, we show that PrAgU2/FP59 is toxic to a wide range of tumor cell lines, including non–small cell lung cancer, pancreatic cancer, and basal-like breast cancer cell lines. Of the few cell lines found to be resistant to PrAgU2/FP59, most became sensitive upon addition of exogenous pro-uPA. PrAgU2/FP59 was much less toxic to normal human cells. The potency of PrAgU2/FP59 was dependent on anthrax toxin receptor, uPA receptor, and uPA levels but not on total plasminogen activator inhibitor-1 levels. In this study, we show that PrAgU2/FP59 is a wide-range, highly potent, and highly selective toxin that is capable of specifically targeting uPA-expressing tumor cells, independently of the tissue of origin of these cells. Furthermore, we identify three molecular markers, anthrax toxin receptor, uPA, and uPA receptor, which can be used as predictors of tumor cell sensitivity to PrAgU2/FP59. [Mol Cancer Ther 2006;5(10):2556–62]
Intratribal Contention Concerning Indian Gaming
Authors: Wetzel Christopher
Published: October 2006

As Indian gaming operations proliferate and public deliberations concerning the propriety of casinos intensify, the academic literature devotes little attention to debates within tribes about Indian gaming. This article interrogates this divergence by examining a specific mode of intratribal contention. Gaming-related occupations staged by factions at the Keweenaw Bay Indian Community and the Kickapoo Traditional Tribe of Texas are described. After locating these practices in the context of approximately half a century of Native American contentious politics, the author considers four questions raised by these cases: (a) Does casino gaming, regardless of the class, have a place on the reservation? (b) How should communities manage the social and economic impacts of casino gaming? (c) Who is, and is not, a member of the community eligible to share in the benefits anticipated to be accrued through gaming? and (d) Who is “traditional” and what does traditional mean?
Activist Research and Student Agency in Universities and Urban Communities
Authors: Mcintyre Alice
Published: October 2006

Unlike school-aged youth attending well-resourced suburban schools, working-class poor students attending inner-city public schools are oftentimes denied the opportunity to develop a sense of agency within their schools and communities. In this article, the author addresses one way that educators and researchers can encourage young people to engage in participatory processes of teaching and learning aimed at developing personal and collective agency. In addition, she describes how a group of university-based students participated in on-the-ground experiences that contributed significantly to their understandings of how individual and collective agency energizes teaching and research processes. The author embeds those discussions within the framework of a participatory action research project she engaged in with a group of middle school adolescents in the northeast region of the United States.
We can Relate
Authors: Stovall David
Published: October 2006

This article seeks to locate hip-hop in the realm of popular culture in education. Through the use of song lyrics, the author suggests the use of rap music to provide context for the humanities and social sciences in secondary curriculum. Using a theoretical and practical lens, the article argues for the use of hip-hop and other elements of popular culture to be utilized to develop relevant curriculum. Although the article highlights one aspect of hip-hop culture, it seeks to advocate for other creative techniques seeking to provide relevance for high school youth.
Urban School Principals and Their Role as Multicultural Leaders
Authors: Gardiner Mary E. , Enomoto Ernestine K.
Published: October 2006

This study focuses on the role of urban school principals as multicultural leaders. Using cross-case analysis, the authors describe what 6 practicing principals do in regard to multicultural leadership. The findings suggest that although multicultural preparation was lacking for these principals, some did engage in work that promoted diversity in their daily activities. All principals dealt with multicultural issues, usually focusing on individual students or specific programs to accommodate immigrants or refugees. Although some principals held high expectations for all, others were less aware of the connection between affirming diversity and student achievement. Recommendations are made to support principals in their work.
Deep mtDNA divergences indicate cryptic species in a fig-pollinating wasp
Authors: Haine Eleanor R , Martin Joanne , Cook James M
Published: October 2006

Background

Figs and fig-pollinating wasps are obligate mutualists that have coevolved for ca 90 million years. They have radiated together, but do not show strict cospeciation. In particular, it is now clear that many fig species host two wasp species, so there is more wasp speciation than fig speciation. However, little is known about how fig wasps speciate.

Results

We studied variation in 71 fig-pollinating wasps from across the large geographic range of Ficus rubiginosa in Australia. All wasps sampled belong to one morphological species (Pleistodontes imperialis), but we found four deep mtDNA clades that differed from each other by 9–17% nucleotides. As these genetic distances exceed those normally found within species and overlap those (10–26%) found between morphologically distinct Pleistodontes species, they strongly suggest cryptic fig wasp species. mtDNA clade diversity declines from all four present in Northern Queensland to just one in Sydney, near the southern range limit. However, at most sites multiple clades coexist and can be found in the same tree or even the same fig fruit and there is no evidence for parallel sub-division of the host fig species. Both mtDNA data and sequences from two nuclear genes support the monophyly of the "P. imperialis complex" relative to other Pleistodontes species, suggesting that fig wasp divergence has occurred without any host plant shift. Wasps in clade 3 were infected by a single strain (W1) of Wolbachia bacteria, while those in other clades carried a double infection (W2+W3) of two other strains.

Conclusion

Our study indicates that cryptic fig-pollinating wasp species have developed on a single host plant species, without the involvement of host plant shifts, or parallel host plant divergence. Despite extensive evidence for coevolution between figs and fig wasps, wasp speciation may not always be linked strongly with fig speciation.
Polarization and orientation of retinal ganglion cells in vivo
Authors: Zolessi Flavio R , Poggi Lucia , Wilkinson Christopher J , Chien Chi-Bin , Harris William A
Published: October 2006

In the absence of external cues, neurons in vitro polarize by using intrinsic mechanisms. For example, cultured hippocampal neurons extend arbitrarily oriented neurites and then one of these, usually the one nearest the centrosome, begins to grow more quickly than the others. This neurite becomes the axon as it accumulates molecular components of the apical junctional complex. All the other neurites become dendrites. It is unclear, however, whether neurons in vivo, which differentiate within a polarized epithelium, break symmetry by using similar intrinsic mechanisms. To investigate this, we use four-dimensional microscopy of developing retinal ganglion cells (RGCs) in live zebrafish embryos. We find that the situation is indeed very different in vivo, where axons emerge directly from uniformly polarized cells in the absence of other neurites. In vivo, moreover, components of the apical complex do not localize to the emerging axon, nor does the centrosome predict the site of axon emergence. Mosaic analysis in four dimensions, using mutants in which neuroepithelial polarity is disrupted, indicates that extrinsic factors such as access to the basal lamina are critical for normal axon emergence from RGCs in vivo.
Independent centromere formation in a capricious, gene-free domain of chromosome 13q21 in Old World monkeys and pigs
Authors: Cardone Maria Francesca , Alonso Alicia , Pazienza Michele , Ventura Mario , Montemurro Gabriella , Carbone Lucia , de Jong Pieter J , Stanyon Roscoe , D'Addabbo Pietro , Archidiacono Nicoletta , She Xinwei , Eichler Evan E , Warburton Peter E , Rocchi Mariano
Published: October 2006

Background

Evolutionary centromere repositioning and human analphoid neocentromeres occurring in clinical cases are, very likely, two stages of the same phenomenon whose properties still remain substantially obscure. Chromosome 13 is the chromosome with the highest number of neocentromeres. We reconstructed the mammalian evolutionary history of this chromosome and characterized two human neocentromeres at 13q21, in search of information that could improve our understanding of the relationship between evolutionarily new centromeres, inactivated centromeres, and clinical neocentromeres.

Results

Chromosome 13 evolution was studied, using FISH experiments, across several diverse superordinal phylogenetic clades spanning >100 million years of evolution. The analysis revealed exceptional conservation among primates (hominoids, Old World monkeys, and New World monkeys), Carnivora (cat), Perissodactyla (horse), and Cetartiodactyla (pig). In contrast, the centromeres in both Old World monkeys and pig have apparently repositioned independently to a central location (13q21). We compared these results to the positions of two human 13q21 neocentromeres using chromatin immunoprecipitation and genomic microarrays.

Conclusion

We show that a gene-desert region at 13q21 of approximately 3.9 Mb in size possesses an inherent potential to form evolutionarily new centromeres over, at least, approximately 95 million years of mammalian evolution. The striking absence of genes may represent an important property, making the region tolerant to the extensive pericentromeric reshuffling during subsequent evolution. Comparison of the pericentromeric organization of chromosome 13 in four Old World monkey species revealed many differences in sequence organization. The region contains clusters of duplicons showing peculiar features.
Fourier Transform Ion Cyclotron Resonance Mass Spectrometry for the Characterisation of Kavalactones in the Kava Plant: Elemental Formulae Confirmation by Dual Spray Accurate Mass Measurement and Structural Confirmation by Infrared Multiphoton Dissociation and Sustained Off-Resonance Irradiation Collision Induced Dissociation
Authors: Warburton Emma , Bristow Tony
Published: October 2006

Roots and extracts of the kava plant have been used in herbal medicine to treat sleep disturbances, stress and anxiety, although reported cases of liver toxicity led to many countries restricting its sale. The detection of the presence of kava in many medicinal products requires the use of methods capable of identifying the kavalactones with high certainty. Here, we describe the use of Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR-MS) for the characterisation of six kavalactones (kavain, dihydrokavain, methysticin, dihydromethysticin, yangonin and desmethoxyyangonin) utilising accurate mass measurement for the determination of their elemental formulae and product ion MS [both sustained off-resonance irradiation collision-induced dissociation and infrared multiphoton dissociation (SORI-CID and IRMPD)] for structural confirmation. High performance liquid chromatography/FT-ICR-MS with a dual spray system for internal calibration of mass spectra was employed for accurate mass measurement and the determination of elemental formulae of the kavalactones in both standards and a root extract to confirm the presence of the kavalactones in the root powder. Mass accuracy of < 1 ppm was achieved. For structural confirmation, the IRMPD and SORI-CID spectra of the kavalactones in standards and a kava root powder extract were compared. Accurate mass measurement of the product ions was also conducted by external calibration and the elemental formula determined to aid with structural confirmation. The presence of the same fragment ions detected in the standards as in the extract further confirmed the presence of the kavalactones in the kava root powder with high certainty.
Fingerprinting of 3, 4-Methylenedioxymethamphetamine Markers by Desorption/Ionization on Porous Silicon
Authors: Kraj Agnieszka , Świst Małgorzta , Strugala Anna , Parczewski Andrzej , Silberringa Jerzy
Published: October 2006

Desorption/ionization on porous silicon (DIOS) is a method which extends the application range of matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. This technique eliminates matrix background in the low mass range; DIOS is especially advantageous in research on small organic molecules and their metabolites in biological samples. DIOS mass spectrometry was applied for 3, 4-methylenedioxymethamphetamine, (MDMA, Ecstasy) impurities identification. Trace component profiling enables the identification of by-product characteristics for the synthesis route of MDMA. Ecstasy, a synthetic psychoactive drug, is highly popular among young people, and often used as a recreational drug, most commonly during disco parties. MDMA enhances feeling of euphoria by increasing the level of neurotransmitters such as serotonin, dopamine and norepinephrine and causes acute behavioral and psychological effects. MDMA is almost exclusively produced illegally, primarily in Western Europe. The new method for MDMA impurities profiling has been developed to trace the origin of MDMA pills. For comparison and classification of the impurity profiles, principal components analysis was used.
A Matrix-Assisted Laser Desorption/Ionization Compatible Reagent for Tagging Tryptophan Residues
Authors: Li Chunyan , Gawandi Vijay , Protos Adam , Phillips Robert S. , Amster I. Jonathan
Published: October 2006

Chemical tagging of amino acids is an important tool in proteomics analysis, and has been used to introduce isotope labels and mass defect labels into proteolytic peptides by derivatization of cysteine or lysine residues. Here, we present a new reagent with chemical specificity for tryptophan residues. Previously, 2-nitrobenzenesulfenyl chloride has been used as a highly specific reagent for labeling tryptophan residues. We show that this tag undergoes UV dissociation during matrix assisted laser desorption/ionization (MALDI). The multiplicity of photofragments increases the difficulty of characterizing the derivatization products. To overcome this problem, we have synthesized a new reagent, 2-(trifluoromethyl)benzenesulfenyl chloride, which is shown to react quantitatively with tryptophan in peptides and proteins. Most significantly, it exhibits high photostability in MALDI-Fourier transform mass spectrometry analyses.
Multi-Stage Collisionally-Activated Decomposition in an Ion Trap for Identification of Sequences, Structures and bn → bn-1 Fragmentation Pathways of Protonated Cyclic Peptides
Authors: Jia Chenxi , Qi Wei , He Zhimin , Qiao Bin
Published: October 2006

Cyclic penta-, hexa- and heptapeptides have been designed, synthesized and their fragmentations induced by multi-stage tandem mass spectrometry have been studied. Under low-energy collisionally-activated decomposition (CAD), the protonated cyclic peptides mainly dissociate via ring opening pathways and the corresponding b n Å b n-1 pathways to form several sets of b ions as oxazolone rings (and b1 ions as aziridinone rings). Through repeated observation of these b ions in multistep CAD experiments, accurate sequencing and head-to-tail ring structure of cyclic peptides can be determined. The mistaken assignments of these b ions can be avoided by this sequencing method. Semi-empirical molecular orbital calculations have been utilized to provide insight into the proposed dissociation mechanism. In addition, for cyclic peptides that include an Asn residue, the nitrogen of the Asn side chain is observed to be preferentially protonated, which can induce a unique ring-opening pathway with a loss of ammonia that competes with the conventional ring opening pathway.
Gas Chromatography/Mass Spectrometric Analysis of N,N-Dialkylaminoethyl-2-Methoxyethyl Ethers as the Decontamination Markers of N,N-Dialkylaminoethyl-2-Chlorides for Verification of the Chemical Weapons Convention
Authors: Gupta Arvinda K. , Pardasani Deepak , Kanaujia Pankaj K. , Tak Vijay , Dubey Devendra K.
Published: October 2006

The detection and identification of markers of scheduled chemicals plays an important role in verification analysis of Chemical Weapons Convention (CWC). This paper describes the gas chromatography electron ionization mass spectrometric (GC/EI-MS) analysis of N,N-dialkylaminoethyl-2-methoxyethyl ethers (DAEMEs), which are identified as characteristic degradation markers of N,N-dialkylaminoethyl-2-chlorides. N,N-dialkylaminoethyl-2-chlorides produced DAEMEs on reacting with the universally used decontamination solution (DS-2). DAEMEs were prepared by condensation of N,N-dialkylaminoethyl-2-chlorides with 2-methoxy ethanol the active ingredient of DS-2. Based on the GC/EI-MS analysis of DAEMEs the generalized fragmentation routes are proposed which rationalize most of the characteristic ions in EI-MS.
Reinventing the Past: Mendelssohn's Antigone and the Creation of an Ancient Greek Musical Language
Authors: GEARY JASON
Published: October 2006

In 1841, Sophocles's Antigone was performed at the Prussian court theater with staging by Ludwig Tieck and music by Felix Mendelssohn. Commissioned by King Friedrich Wilhelm IV, this production aimed to re-create aspects of Greek tragedy by, among other things, using J. J. Donner's 1839 metrical translation and having an all-male chorus sing the odes. Mendelssohn initially experimented with imitating the purported sound of ancient music by composing primarily unison choral recitative and limiting the accompaniment to flutes, tubas, and harps; but he quickly abandoned this approach in favor of a more traditional one. Yet despite his overall adherence to modern convention, he did employ several strategies to evoke ancient Greek practice and thus to meet the unique demands of the Prussian court production.

Highlighting important distinctions between verse-types in the original poetry, Mendelssohn retained a vestige of his initial approach by composing unison choral recitative to indicate the presence of anapestic verse while turning to melodrama for the lyric verse of the play's two main characters. In addition, he reproduced the poetic meter by shaping the rhythm of the vocal line to reflect both the accentual pattern of Donner's translation and, in some cases, the long and short syllables of Sophocles's Greek verse. Owing largely to the irregular line lengths characteristic of Donner's text, the music is marked by conspicuously asymmetrical phrases, which serve to defamiliarize the otherwise straightforward choral styles being employed to convey the various moods of Sophocles's choruses. In the opening chorus, Mendelssohn alludes to the familiar sound of a Männerchor accompanied by a wind band, thereby suggesting the ode's celebratory and martial associations while recalling his own Festgesang written for the 1840 Leipzig festival commemorating the 400th anniversary of Gutenberg's printing press. The listener is thus presented with a thoroughly recognizable musical idiom and yet simultaneously distanced from it in a way that underscores the historical remoteness of ancient Greek tragedy.
The Cantata for the Twentieth Anniversary of October, or How the Specter of Communism Haunted Prokofiev
Authors: MORRISON SIMON , KRAVETZ NELLY
Published: October 2006

Prokofiev composed his Anniversary Cantata for the Twentieth of October in order to win favor with Soviet cultural officials. However, his decision to set authentic texts by Lenin, Marx, and Stalin, together with his decision to edit these texts to ensure musical cohesion, proved to be highly controversial. In 1937, the cantata came in for harsh criticism from the watchdog Committee of Artistic Affairs and was barred from performance. Prokofiev responded to the setback by retooling his creative methods and by composing a Party-line paean to Stalin.
Enthusiasm and Its Discontents: Religion, Prophecy, and Madness in the Music for Sophonisba and The Island Princess
Authors: WINKLER AMANDA EUBANKS
Published: October 2006

Enthusiasm, a state in which the soul is supposedly freed from the body and the human vessel is filled with the divine, troubled the religious mainstream in 17th-century England. During the English Civil War, radical Protestant sects used enthusiastic prophecy to justify rebellion against monarchical tyranny. Such practices drew fire from members of the Church of England who vilified the prophets' “religious enthusiasm” by associating it with madness and melancholy. This strategy pathologized enthusiasm, transforming it into a mental disorder.

Anti-enthusiastic discourses shaped musical and dramatic practices on the Restoration stage, as witnessed in two songs for enthusiastic prophets, Cumana in Nathaniel Lee's Sophonisba (music by Henry Purcell for a 1690s revival) and the elderly Brahmin priest in Peter Motteux's revision of The Island Princess (music by Richard Leveridge, 1699). Purcell's song for Cumana, “Beneath a Poplar's Shadow,” incorporates the standard conventions of musical madness and is even called a “mad song” in Orpheus Britannicus, Book Two (1702). Similarly, the Brahmin priest channels the speech of the false pagan gods in Leveridge's “Enthusiastick Song”—a piece that parallels contemporary political discourses about the “madness” of religious nonconformity and fanaticism. A close reading of the music, dramatic texts, and contemporary political, religious, and medical discourses demonstrates how musical representations of enthusiasm were affected by the critical rhetoric of religious orthodoxy.
Modelling deterioration of structural behaviour of reinforced concrete beams under saline environment corrosion
Authors: Melchers R. E. , Li C. Q. , Lawanwisut W.
Published: October 2006

In the assessment of existing structures the likely future deterioration of strength and stiffness is of interest. For reinforced concrete beams one of the most important influencing factors is the loss of reinforcement cross-sectional area at critical locations. Because corrosion is a long-term process for well-designed structures, there is only limited field experience available on which to draw and with which to make empirical rules. The considerable research effort in corrosion of reinforcement in concrete structures has focused mainly on the rate of migration of chloride ions from the environment through the concrete to the corroding steel surface. This will estimate the time before reinforcement corrosion becomes significant but does not provide the rate of structural deterioration. In the present paper a method is proposed for estimating structural deterioration, based on evidence that (a) reinforcement corrosion causes internal damage to and loss of bond with the surrounding concrete and (b) chloride diffusion is influenced by stresses set up in the concrete by external loading. Both these factors affect the rate of chloride migration locally and hence the amount of corrosion and material strength loss at any point in time. The proposed method is outlined and an example application given. Reasonably good agreement between the results of the proposed procedure and the few experimental results was obtained.
Effect of tensile softening relation on size effect of concrete in bending
Authors: Zhang J.
Published: October 2006

In the current paper, the effect of tensile softening parameters, the tensile strength σt and the initial slope k1 of the stress-crack width curve, on the structural size-effect law in bending of concrete are studied by a bending model. The model results show that the size-effect law in bending strength normally presented by flexural strength and beam height diagram (σf–logH) is strongly dependent on σt and k1. With increase of beam height, the general size-effect law in bending can be characterised as a fast reduction stage followed by a stable decreasing stage and finally converged to the tensile strength of concrete. With increasing tensile strength, the σf–logH curve goes up and the value of dσf/dlogH gradually increases. In the meantime, for a given beam height, bending strength increases with increase of k1. The model predictions are compared with experimental results. Good agreement between model predictions and experiments has been obtained.
A novel G106D alteration of the SDHD gene in a pedigree with familial paraganglioma
Authors: Ogawa Kazumi , Shiga Kiyoto , Saijo Shigeru , Ogawa Takenori , Kimura Noriko , Horii Akira
Published: October 2006

Head and neck paragangliomas are tumors derived from parasympathetic paraganglia. Familial cases account for 10% or more of these tumors, and mutations of the genes encoding subunits for the mitochondrial respiratory chain complex II, SDHD, SDHB, and SDHC, have been reported. We analyzed mutations in the all four SDH genes, SDHA through SDHD, in a Japanese family with cervical paraganglioma that include a father with bilateral tumors and his daughter with a malignant left carotid body tumor with nodal metastasis. This pedigree harbored a germline G106D alteration in exon 4 of the SDHD gene that has not previously been reported to date. The tumors of the father expressed biallelic SDHD, but the SDHD expression was highly suppressed by an unknown mechanism(s) in tumors of his daughter, and the wild‐type allele was predominantly suppressed in the metastatic node. These results suggest that the missense dysfunction of SDHD prepares neoplastic condition and that expressional silencing, particularly of the wild‐type allele, plays an important role in the malignant transformation of the paragangliomas. Our results may lead to a better understanding of this disease and to the development of methods for prevention of this disease. © 2006 Wiley‐Liss, Inc.
RAI1 point mutations, CAG repeat variation, and SNP analysis in non‐deletion Smith–Magenis syndrome
Authors: Bi Weimin , Saifi G. Mustafa , Girirajan Santhosh , Shi Xin , Szomju Barbara , Firth Helen , Magenis R. Ellen , Potocki Lorraine , Elsea Sarah H. , Lupski James R.
Published: October 2006

Smith–Magenis syndrome (SMS) is a multiple congenital anomalies/mental retardation disorder characterized by distinct craniofacial features and neurobehavioral abnormalities usually associated with an interstitial deletion in 17p11.2. Heterozygous point mutations in the retinoic acid induced 1 gene (RAI1) have been reported in nine SMS patients without a deletion detectable by fluorescent in situ hybridization (FISH), implicating RAI1 haploinsufficiency as the cause of the major clinical features in SMS. All of the reported point mutations are unique and de novo. RAI1 contains a polymorphic CAG repeat and encodes a plant homeo domain (PHD) zinc finger‐containing transcriptional regulator. We report a novel RAI1 frameshift mutation, c.3103delC, in a non‐deletion patient with many SMS features. The deletion of a single cytosine occurs in a heptameric C‐tract (CCCCCCC), the longest mononucleotide repeat in the RAI1 coding region. Interestingly, we had previously reported a frameshift mutation, c.3103insC, in the same mononucleotide repeat. Furthermore, all five single base frameshift mutations preferentially occurred in polyC but not polyG tracts. We also investigated the distribution of the polymorphic CAG repeats in both the normal population and the SMS patients as one potential molecular mechanism for variability of clinical expression. In this limited data set, there was no significant association between the length of CAG repeats and the SMS phenotype. However, we identified a 5‐year‐old girl with an apparent SMS phenotype who was a compound heterozygote for an RAI1 missense mutation inherited from her father and a polyglutamine repeat of 18 copies, representing the largest known CAG repeat in this gene, inherited from her mother. © 2006 Wiley‐Liss, Inc.
Antenatal screening tests: Knowledge and practice patterns of obstetricians in Utah
Authors: Fisher Barbra M. , Varner Michael , Rose Nancy C.
Published: October 2006

We sought to assess knowledge and practices of obstetricians regarding antenatal testing and test the efficacy of continuing education via a direct mailing. In June 2004, an educational brochure entitled “New Options for Maternal Serum Screening for Birth Defects” as well as an anonymous survey pertaining to antenatal testing was sent to 241 American College of Obstetricians and Gynecologists (ACOG) Fellows and Junior Fellows residing in Utah. Data from the 85 (35%) respondents were analyzed. The majority of respondents practice obstetrics (81/85, or 95%). Of these, 67% of respondents perform sonograms routinely in their offices. Respondents were distributed evenly across all years of practice. Respondents offer HIV screening routinely (85%), but only 40% follow ACOG cystic fibrosis (CF) screening recommendations. Midtrimester serum screening is offered routinely by 89% of the respondents, but only 54% adequately understood the capabilities and limitations of the test. Questions related to the patient education brochure included in the mailing were answered correctly more often than the other questions. The brochure emphasized the usefulness of combined integrated screening for detecting Down syndrome, and 94% of respondents subsequently understood this concept. We show that in Utah, ACOG recommendations for HIV and maternal serum testing are being followed uniformly, but CF screening is still not being routinely offered. The accurate responses to questions related to an enclosed education brochure suggest that direct mailings may be useful for provider education, especially in regions where many providers practice remote from academic centers. © 2006 Wiley‐Liss, Inc.