bluuebunny/crossref_metadata_2025 huggingface dataset:
Genetic counseling and ethical issues for autism
Authors: McMahon William M. , Baty Bonnie Jeanne , Botkin Jeffrey
Published: January 2006

Exciting progress is being made in the journey toward discovery of genes conferring risk for autism and autism spectrum disorders. Currently, genetic counseling for idiopathic autism rests on clinical diagnosis and empiric risk estimates. While no genetic test for risk of autism currently exists, it is possible that such a test may emerge in the near future, and that commercial availability may precede adequate understanding of test characteristics. The complexity of multifactorial conditions like autism raises a host of ethical and counseling challenges. For families to benefit from new genetic knowledge about autism, it will be important for their practitioners to be knowledgeable about the issues, utilize appropriate educational interventions and emerging management options, and help families across the cultural spectrum cope with these challenges. © 2006 Wiley‐Liss, Inc.
CPR, on members' behalf, responds to European commission mediation queries
Authors: Bleemer Russ
Published: January 2006

On behalf of seven members, the CPR Institute files a response to nine questions posed by a member of the European Commission's parliament on whether the EC should push for more commercial mediation, and how it should do so if it decides to proceed with a proposed directive. Also, the fourth volume in CPR's new Master Guides series is set for release
Evaluating the information quality of Web sites: A methodology based on fuzzy computing with words
Authors: Herrera‐Viedma Enrique , Pasi Gabriella , Lopez‐Herrera Antonio G. , Porcel Carlos
Published: January 2006

An evaluation methodology based on fuzzy computing with words aimed at measuring the information quality of Web sites containing documents is presented. This methodology is qualitative and user oriented because it generates linguistic recommendations on the information quality of the content‐based Web sites based on users' perceptions. It is composed of two main components, an evaluation scheme to analyze the information quality of Web sites and a measurement method to generate the linguistic recommendations. The evaluation scheme is based on both technical criteria related to the Web site structure and criteria related to the content of information on the Web sites. It is user driven because the chosen criteria are easily understandable by the users, in such a way that Web visitors can assess them by means of linguistic evaluation judgments. The measurement method is user centered because it generates linguistic recommendations of the Web sites based on the visitors' linguistic evaluation judgments. To combine the linguistic evaluation judgments we introduce two new majority guided linguistic aggregation operators, the Majority guided Linguistic Induced Ordered Weighted Averaging (MLIOWA) and weighted MLIOWA operators, which generate the linguistic recommendations according to the majority of the evaluation judgments provided by different visitors. The use of this methodology could improve tasks such as information filtering and evaluation on the World Wide Web.
Characterization of bacterial growth and the influence of antibiotics by means of UV resonance Raman spectroscopy
Authors: Neugebauer U. , Schmid U. , Baumann K. , Holzgrabe U. , Ziebuhr W. , Kozitskaya S. , Kiefer W. , Schmitt M. , Popp J.
Published: January 2006

In this work we monitor the bacterial growth of a Bacillus pumilus batch culture by means of UV resonance Raman spectroscopy. Excitation with a wavelength of 244 nm especially enhances the Raman scattering of the aromatic amino acids and the nucleic acid bases and therefore is a good method to track the metabolic changes that occur during bacterial growth. Furthermore, a drug from the fluoroquinolone group is added to the bacterial suspension at the beginning of the exponential growth phase. With the help of chemometrical methods such as hierarchical cluster analysis (HCA) and principal component analysis (PCA) it is possible to visualize the small changes that occur in the UV resonance Raman spectra due to the interaction of the drug with its biological targets DNA and the enzyme gyrase within the bacterial cell. © 2006 Wiley Periodicals, Inc. Biopolymers 82: 306–311, 2006

This article was originally published online as an accepted preprint. The “Published Online” date corresponds to the preprint version. You can request a copy of the preprint by emailing the Biopolymers editorial office at biopolymers@wiley.com
Surface‐enhanced Raman scattering study of the interaction of red dye alizarin with ovalbumin
Authors: Cañamares M. V. , Sevilla P. , Sanchez‐Cortes S. , Garcia‐Ramos J. V.
Published: January 2006

Surface‐enhanced Raman spectroscopy and UV–vis absorption spectroscopy were employed to study the interaction between the red dye alizarin and ovalbumin (OA), to check the effect of binding media usually employed when applying this pigment in painting practices based on egg tempera. The protein/alizarin interaction is rather weak and takes place through the alizarin neutral form, which interacts with exposed hydrophobic moieties of OA. This effect is of great interest from an artistic point of view because the dye color can be modified. Furthermore, the interaction with alizarin could induce a change in the protein structure, leading to a denaturation and subsequent aggregation. © 2006 Wiley Periodicals, Inc. Biopolymers 82: 405–409, 2006

This article was originally published online as an accepted preprint. The “Published Online” date corresponds to the preprint version. You can request a copy of the preprint by emailing the Biopolymers editorial office at biopolymers@wiley.com
Bis(calixcrown)tetrathiafulvalene Receptors
Authors: Blesa María‐Jesús , Zhao Bang‐Tun , Allain Magali , Le Derf Franck , Sallé Marc
Published: January 2006

A new class of electroactive receptors has been synthesized, built by covalent association of five subunits: two calixarene platforms for spatial organization, two polyether 3D cavities for cation binding, and one electroactive TTF unit to probe the complexation event. Sodium complexation induces rigidification of the molecular assembly, as shown by 1H NMR titration and single‐crystal X‐ray crystallographic studies on free receptor 14 and a corresponding complex with two bound sodium atoms per receptor (15‐(NaPF6)2). The calixarene units in these receptors change from a pinched cone conformation in the free ligand to a symmetrical cone in the complex. Cyclovoltammetric studies validated the electrochemical recognition concept of these five‐member assemblies.
New Cyanine–Oligonucleotide Conjugates: Relationships between Chemical Structures and Properties
Authors: Lartia Rémy , Asseline Ulysse
Published: January 2006

Because the influence of the chemical structure of monomethine cyanine–oligo‐2′‐deoxyribonucleotide (ODN) conjugates on their binding and fluorescence properties has remained largely undetermined, we synthesized and studied a wide range of conjugates with various structural patterns. Different cyanine dyes such as thiocyanine, quinocyanine, and thiazole orange isomers were obtained. In the case of unsymmetrical cyanines, the linker was attached to either the quinoline or the benzothiazole nucleus. The influence of the ODN counterpart was evaluated by linking the cyanines to the 5′‐end or to an internucleotidic phosphate. In the first case, the influence of neighboring nucleic bases was studied, whereas in the second, the stereochemical configuration at the phosphorus atom bearing the cyanine was investigated. We report here on relationships between the structures of the dyes and conjugates and some of their properties, such as the stability and fluorescence changes observed on their hybridization with the target sequence. This study provides useful information towards the design of ODN–cyanine conjugates.
Self‐organized and highly ordered domain structures within swarms of Myxococcus xanthus
Authors: Pelling Andrew E. , Li Yinuo , Cross Sarah E. , Castaneda Schryl , Shi Wenyuan , Gimzewski James K.
Published: January 2006

Coordinated group movement (swarming) is a key aspect of Myxococcus xanthus' social behavior. Here we report observation of domain structures formed by multiple cells within large three‐dimensional swarming groups grown on amorphous glass substrates, using the atomic force microscope (AFM). Novel analyses revealed that ˜90% of the wild type swarms displayed some form of preferential cell alignment. In contrast, cells with mutations in the social and adventurous motility systems displayed a distinct lack of cell alignment. Video microscopy observations of domain features of in vivo swarming M. xanthus cells were also consistent with the AFM data. The results presented here reveal that unique domain formation within swarms of wild type cells is a biologically driven process requiring the social and adventurous motility systems and is not a statistical phenomenon or thermodynamic process arising from liquid crystal behavior. Cell Motil. Cytoskeleton 63, 2006. © 2006 Wiley‐Liss, Inc.
A critical role for the type V myosin, Myo52, in septum deposition and cell fission during cytokinesis in Schizosaccharomyces pombe
Authors: Mulvihill Daniel P. , Edwards Suzanne R. , Hyams Jeremy S.
Published: January 2006

Cytokinesis in fission yeast involves the coordination of septum deposition with the contraction of a cytokinetic actomyosin ring. We have examined the role of the type V myosin Myo52 in the coupling of these two events by the construction of a series of deletion mutants of the Myo52 tail and a further mutant within the ATP binding domain of the head. Each mutant protein was ectopically expressed in fission yeast cells. Each truncation was assayed for the ability to localize to the cell poles and septum (the normal cellular locations of Myo52) and to rescue the morphology defects and temperature sensitivity of a myo52Δ strain. A region within the Myo52 tail (amino acids 1320–1503), with a high degree of similarity to the vesicle‐binding domain of the budding yeast type V myosin Myo2p, was essential for Myo52's role in the maintenance of growth polarity and cell division. A separate region (amino acids 1180–1320) was required for Myo52 foci to move throughout the cytoplasm; however, constructs lacking this region, but which retained the ability to dimerize still associated with actin at sites of cell growth. Not all of the Myo52 truncations which localized rescued the morphological defects of myo52Δ, demonstrating that loss of function was not simply brought about by an inability of mutant proteins to target the correct cellular location. By contrast, Myo52 motor activity was required for both localization and cellular function. myo52Δ cells were unable to efficiently localize the β‐1,3‐glucan synthase, Bgs1, either at the cell poles or at the division septum, regions of cell wall deposition. Bgs1 and Myo52 localized to vesicle‐like dots at the poles in interphase and these moved together to the septum at division. These data have led to the formulation of a model in which Myo52 is responsible for the delivery of Bgs1 and associated molecules to polar cell growth regions during interphase. On the commencement of septum formation, Myo52 transports Bgs1 to the cell equator, thus ensuring the accurate deposition of β‐1,3‐glucan at the leading edge of the primary septum. Cell Motil. Cytoskeleton 2006. © 2006 Wiley‐Liss, Inc.
In utero exposure to female hormones and germ cell tumors in children
Authors: Shankar Sadhna , Davies Stella , Giller Roger , Krailo Mark , Davis Mary , Gardner Kathleen , Cai Hui , Robison Leslie , Shu Xiao‐Ou
Published: January 2006

BACKGROUND

Maternal exposure to exogenous female hormones during pregnancy has been implicated as a risk factor for malignant germ cell tumors (GCTs) in the offspring in some epidemiologic studies of testicular and ovarian carcinoma in adults.

METHODS

From 1996 to 2002, 278 children younger than 15 years of age with malignant GCTs and 423 healthy controls, frequency‐matched for geographic location, age, and sex were enrolled in a case–control study to investigate whether in utero exposure to female hormones is associated with the risk of malignant GCT in children. Cases were recruited from 84 institutions in the U.S. and controls were enrolled through random digit dialing. Information was obtained through telephone interview with the biological mothers of the subjects and through blinded review of the mothers' medical records.

RESULTS

Neither self‐reported (odds ratio [OR] = 1.15; 95% confidence interval [CI], 0.63, 2.12) nor medical chart based (OR = 1.14; 95% CI, 0.75, 1.73) maternal exposure to exogenous female hormones was related to malignant GCT risk. Pregnancy‐related conditions that may have altered serum levels of circulating female hormones were also unrelated to the risk of GCT in the offspring.

CONCLUSION

This study failed to provide strong evidence to support the hypothesis that maternal exposure to exogenous female hormones during pregnancy increases the risk of GCT in the offspring. Cancer 2006. © 2006 American Cancer Society.
Are all melanomas the same?
Authors: Lee David A. , Cohen Jason A. , Twaddell William S. , Palacios Gustavo , Gill Melissa , Levit Eyal , Halperin Alan J. , Mones Joan , Busam Klaus J. , Silvers David N. , Celebi Julide Tok
Published: January 2006

BACKGROUND

Although the majority of melanomas demonstrate high rates of mutations in B‐RAF or N‐RAS that result in constitutive activation of the mitogen‐activated protein kinase‐signaling pathway, emerging data suggest molecular differences among melanoma subtypes. In this study, the authors evaluated the contribution of B‐RAF and N‐RAS mutations to the pathogenesis of Spitzoid melanomas.

METHODS

In total, 33 Spitzoid melanomas were analyzed for clinical and pathologic characteristics as well as for hot‐spot mutations in the B‐RAF and N‐RAS genes. In the majority of patients (28 of 33 melanomas), the tumors were confined to the skin with no evidence of metastasis (average follow‐up, 32.5 mos). There were five metastasizing melanomas (5 of 33 tumors) with regional or systemic spread.

RESULTS

Of 33 Spitzoid melanomas, only 1 showed the V600E mutation in the B‐RAF gene (1 of 33 tumors; 3%). It was noteworthy that none of the metastatic Spitzoid melanomas (0 of 5 tumors; 0%), of which 2 resulted in fatal outcomes, demonstrated mutations in B‐RAF or N‐RAS.

CONCLUSIONS

In contrast to the majority of cutaneous melanomas, activating hot‐spot mutations in B‐RAF or N‐RAS were not involved in the pathogenesis of Spitzoid melanoma. These data suggested that Spitzoid melanoma is a distinct form of melanoma with unknown genes and/or signaling pathways involved in its development. Cancer 2006. © 2006 American Cancer Society.
Prognostic factors for osteosarcoma of the extremity treated with neoadjuvant chemotherapy
Authors: Bacci Gaetano , Longhi Alessandra , Versari Michela , Mercuri Mario , Briccoli Antonio , Picci Piero
Published: January 2006

BACKGROUND

The evaluation variables influencing systemic and local recurrence and final outcome are extremely important in defining risk‐adapted treatments for patients with nonmetastatic osteosarcoma of the extremity.

METHODS

A homogeneous group of 789 patients treated at a single institution between March 1983 and March 1999 with different protocols of neoadjuvant chemotherapy, with a minimum followup of 5 years, were retrospectively evaluated in relation to gender, age, serum levels of alkaline phosphatase, tumor site and size of the pathologic fracture, type of surgery, protocol of chemotherapy, surgical margins, and histologic response to preoperative treatment.

RESULTS

The 5‐year event‐free survival (EFS) and overall survival rates were 60.1% and 67.5%, respectively. Upon univariate analysis, EFS was significantly related to the age of patients, serum value of alkaline phosphatase, tumor volume, histologic subtype, type of surgery, surgical margins, histologic response to preoperative treatment, and chemotherapy protocol. Local recurrences (4.8%) were significantly correlated with surgical margins. The 5‐year postrecurrence EFS survival was 17% and was significantly lower for patients who had a local recurrence and metastases than for those with metastases only. Patients who had a recurrence only in the lung had a postrecurrence survival rate significantly better than others, correlated with the number of metastatic nodules and the length of the disease‐free interval.

CONCLUSIONS

Upon multivariate analysis, age ≤ 14 years, high serum levels of alkaline phosphatase, tumor volume > 200 mL, a two‐drug regimen chemotherapy, inadequate surgical margins, and poor histologic response to treatment maintained independent prognostic values on the outcome of nonmetastatic osteosarcoma of the extremities. These factors must be considered when deciding risk‐adapted treatments for osteosarcoma patients. Cancer 2006. © 2006 American Cancer Society.
A developmental fMRI study of self‐regulatory control
Authors: Marsh Rachel , Zhu Hongtu , Schultz Robert T. , Quackenbush Georgette , Royal Jason , Skudlarski Pawel , Peterson Bradley S.
Published: January 2006

We used functional magnetic resonance imaging (fMRI) to investigate the neural correlates of self‐regulatory control across development in healthy individuals performing the Stroop interference task. Proper performance of the task requires the engagement of self‐regulatory control to inhibit an automatized response (reading) in favor of another, less automatic response (color naming). Functional MRI scans were acquired from a sample of 70 healthy individuals ranging in age from 7 to 57 years. We measured task‐related regional signal changes across the entire cerebrum and conducted correlation analyses to assess the associations of signal activation with age and with behavioral performance. The magnitude of fMRI signal change increased with age in the right inferolateral prefrontal cortex (Brodmann area [BA] 44/45) and right lenticular nucleus. Greater activation of the right inferolateral prefrontal cortex also accompanied better performance. Activity in the right frontostriatal systems increased with age and with better response inhibition, consistent with the known functions of frontostriatal circuits in self‐regulatory control. Age‐related deactivations in the mesial prefrontal cortex (BA 10), subgenual anterior cingulate cortex (BA 24), and posterior cingulate cortex (BA 31) likely represented the greater engagement of adults in self‐monitoring and free associative thought processes during the easier baseline task, consistent with the improved performance on this task in adults compared with children. Although we cannot exclude the possibility that age‐related changes in reading ability or in the strategies used to optimize task performance were responsible for our findings, the correlations of brain activation with performance suggest that changes in frontostriatal activity with age underlie the improvement in self‐regulatory control that characterizes normal human development. Hum Brain Mapp, 2006. © 2006 Wiley‐Liss, Inc.
Automatic detection and verification of solar features
Authors: Qahwaji R. , Colak T.
Published: January 2006

A fast hybrid system for the automated detection and verification of active regions (plages) and filaments in solar images is presented in this paper. The system combines automated image processing with machine learning. The imaging part consists of five major stages. The solar disk is detected in the first stage, using a morphological hit‐miss transform, watershed transform and Filling algorithm. An image‐enhancement technique is introduced to remove the limb‐darkening effect and intensity filtering is implemented followed by a modified region‐growing technique to detect the regions of interest (RoI). The algorithms are tested on H‐α and CA II K3‐line solar images that are obtained from Meudon Observatory, covering the period from July 2, 2001 till August 4, 2001. The detection algorithm is fast and it achieves false acceptance rate (FAR) error rate of 67% and false rejection rate (FRR) error rate of 3% for active regions, and FAR error rate of 19% and FRR error rate of 14% for filaments, when compared with the manually detected filaments in the synoptic maps. The detection performance is enhanced further using a neural network (NN), which is trained on statistical features extracted from the RoI and non‐RoI. With the use of this combination the FAR has dropped to 2% for active regions and 4% for filaments.© 2006 Wiley Periodicals, Inc. Int J Imaging Syst Technol, 15, 199–210, 2005
A system for matching moving vehicles across different camera sites in outdoor environments
Authors: Lao Y. , Leung C. H. , Hung Y. S.
Published: January 2006

A method for identifying the same running vehicle from images captured at different camera sites is proposed. This is achieved through an image matching process. With cameras installed at the inlets and exits of highways and at crossroads in a road network, the system can be used for tracking the routes of individual vehicles and computing the times of traveling from one site to another. The system has the advantages of being low cost and not requiring sophisticated imaging hardware. Contributions include (i) a novel background removal method that employs the robust RANSAC algorithm for estimation, (ii) an elaborate shadow removal algorithm, and (iii) an effective license plate matching method applicable to poor quality images.© 2006 Wiley Periodicals, Inc. Int J Imaging Syst Technol, 15, 211–219, 2005
Optimization and integration of high‐performance ground penetrating imaging radar system: A research prototype
Authors: Lee Michael , Ono Sashi
Published: January 2006

This paper reports the design, development, and field experimentation of a new ground penetrating imaging radar system. This research prototype unit features full system optimization, which successfully integrates the key components of antenna sensitivity, data‐acquisition waveforms, synthetic‐aperture scan, and image reconstruction algorithms, for optimal system performance.© 2006 Wiley Periodicals, Inc. Int J Imaging Syst Technol, 15, 220–223, 2005
Warfarin resistance in a French strain of rats
Authors: Lasseur Romain , Longin‐Sauvageon Christiane , Videmann Bernadette , Billeret Mikaëline , Berny Philippe , Benoit Etienne
Published: January 2006

A warfarin‐resistant strain and a warfarin‐susceptible strain of wild rats (Rattus norvegicus) maintained in enclosures of the National Veterinary School of Lyon (France) were studied to determine the mechanism of the resistance to anticoagulant rodenticides. A low vitamin K epoxide reductase (VKOR) activity has been reported for many resistant rat strains. As recently suggested, mutations in the vitamin K epoxide reductase subunit 1 (VKORC1) gene are the genetic basis of anticoagulant resistance in wild populations of rats from various locations in Europe. Here we report, for our strain, one of the seven described mutations (Tyr139Phe) for VKORC1 in rats. In addition, a low expression of mRNA encoding VKORC1 gene is observed in resistant rats, which could explain their low VKOR activity. We calculated kinetic parameters of VKOR in the warfarin‐resistant and warfarin‐susceptible rats. The Vmax and the Km of the VKOR obtained in resistant rats were lowered by 57 and 77%, respectively, compared to those obtained in susceptible rats. As a consequence, the enzymatic efficiency (Vm/Km) of the VKOR was similar between resistant and susceptible rats. This result could be a good explanation to the observation that no clinical signs of vitamin K deficiency was observed in the warfarin‐resistant strain, while a low VKOR activity was found. VKOR activity in warfarin‐resistant rats was poorly inhibited by warfarin (Ki for warfarin is 29 μM and 0.72 μM for resistant and susceptible rats, respectively). © 2005 Wiley Periodicals, Inc. J Biochem Mol Toxicol 19:379‐385, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/jbt.20104
Chemopreventive activity of selenocysteine prodrugs against tobacco‐derived nitrosamine (NNK) induced lung tumors in the A/J mouse
Authors: Li Liang , Xie Yang , El‐Sayed Wael M. , Szakacs Juliana G. , Franklin Michael R. , Roberts Jeanette C.
Published: January 2006

Prodrugs of L‐selenocysteine have potential utility in cancer chemoprevention. This study reports the efficacy of three selenazolidine‐4(R)‐carboxylic acids, (2‐unsubstituted, 2‐oxo, and 2‐methyl derivatives; SCA, OSCA, and MSCA, respectively) against tobacco‐related lung tumorigenesis in a mouse model. Seven days after initiation of an AIN‐76A diet supplemented with sodium selenite (5 ppm Se), L‐selenomethionine (3.75 ppm Se), Se‐methyl‐L‐selenocysteine (3 ppm Se), L‐selenocystine (15 ppm Se), SCA (15 ppm Se), OSCA (15 ppm Se), or MSCA (15 ppm Se), mice received 4‐(methylnitrosamino)‐1‐(3‐pyridyl)‐1‐butanone (NNK; 10 μmol, i.p.). After an additional 16 weeks on the diets, two compounds, OSCA and selenocystine, significantly reduced lung adenoma multiplicity from 7.2 tumors per mouse in the NNK group to 4.5 and 4.6 tumors per mouse, respectively. Neither selenium concentration nor glutathione peroxidase activity in either RBCs or liver served as surrogate indicators of tumor reduction. Hepatic selenium levels were significantly elevated by all selenium‐containing compounds except Se‐methyl‐L‐selenocysteine and SCA; RBC selenium levels by all except sodium selenite and MSCA. With the exception of L‐selenomethionine, RBC glutathione peroxidase activity was increased along with the elevated selenium levels. Hepatic glutathione peroxidase activity was elevated by all Se‐compounds except SCA. The two compounds showing significant tumor reduction (OSCA and selenocystine) were the only two compounds that showed ubiquity of changes, elevating both selenium levels and GPx activity in both liver and RBC. © 2005 Wiley Periodicals, Inc. J Biochem Mol Toxicol 19:396‐405, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/jbt.20105
New force field for calcium binding sites in annexin–membrane complexes
Authors: Merzel Franci , Hodošček Milan , Janežič Dušanka , Sanson Alain
Published: January 2006

For accurate classical molecular dynamics (MD) simulations of the calcium mediated bound complexes of annexin and membrane we have developed new force‐field parameters correctly describing the interaction of the Ca ion with its environment. We have used quantum chemical calculations to investigate the potential energy surface experienced by the Ca ion within the three different binding sites found in domain 1 of annexin V (ANX V/1). Based on these calculations we were able to quantify the charge polarization of atoms within the binding sites, and to determine the geometry and force constants of harmonic restraints between the Ca ion and its coordinating oxygen atoms. Harmonic restraints were introduced to compensate for the deviations between the quantum mechanical potential energy surface and that of the classical force field. Our analysis has shown that using the refined force field for the Ca binding sites enables long‐time MD simulations that conserve the initial structure of ANX V/1 significantly better than MD simulations using the standard force field. © 2006 Wiley Periodicals, Inc. J Comput Chem 27: 446–452, 2006
Relativistic correlating basis sets for lanthanide atoms from Ce to Lu
Authors: Sekiya Masahiro , Noro Takeshi , Miyoshi Eisaku , Osanai You , Koga Toshikatsu
Published: January 2006

Contracted Gaussian‐type function (CGTF) sets for the description of the 4f subshell correlation and of the 6s and 5d subshell correlation are developed for lanthanide atoms from Ce to Yb. Also prepared are basis sets for the 5d orbitals, which are vacant in the ground states of most lanthanide atoms but are essential in molecular environments. In addition, correlating CGTF sets for the 4f subshell correlation are supplemented for the Lu atom. A segmented contraction scheme is employed for their compactness and efficiency. Contraction coefficients and exponents are determined by minimizing the deviation from accurate natural orbitals generated from configuration interaction calculations that include relativistic effects through the third‐order Douglas–Kroll approximation. All‐electron and model core potential calculations with the present correlating sets are performed on the ground state of the diatomic CeO molecule. The calculated spectroscopic constants are in good agreement with experimental values. © 2006 Wiley Periodicals, Inc. J Comput Chem 27:463–470, 2006
Characterization of host–guest complexes of cucurbit[n]uril (n = 6, 7) by electrospray ionization mass spectrometry
Authors: Osaka Issey , Kondou Masanobu , Selvapalam Narayanan , Samal Shashadhar , Kim Kimoon , Rekharsky Mikhail V. , Inoue Yoshihisa , Arakawa Ryuichi
Published: January 2006

When an intramolecular cavity exists in a molecule, it can trap another chemical species to form a host–guest complex. We examine the formation of such an inclusion complex with cucurbit[n]uril (CBn, n = 6, 7) as the host to trap alkali metal or ammonium ions as the guest, by electrospray ionization mass spectrometry (ESI‐MS). The results show that the inclusion complexes are formed between the three‐dimensional cylinder of CBn hosts and the guest cations. Selectivity of the complex formation is dependent both on (1) ion–dipole interactions between the cylindrical portal of the CBn hosts and the guest cations and (2) the hydrophobic interactions at the inner cavity of CBn. Copyright © 2006 John Wiley & Sons, Ltd.
Reactions of a modified lysine with aldehydic and diketonic dicarbonyl compounds: an electrospray mass spectrometry structure/activity study
Authors: Saraiva Marco A. , Borges Carlos M. , Florêncio M. Helena
Published: January 2006

The phenomenon known as non‐enzymatic glycation is described as the reaction of reducing sugars with basic amino groups of proteins and nucleic acids, as well as with simple amines, without enzyme mediation. Non‐enzymatic model glycation reactions that make use of low‐molecular‐weight compounds make an important contribution in the elucidation of glicated processes in vitro and in vivo. Four α‐dicarbonyl compounds, aldehydic (glyoxal, methylglyoxal and phenylglyoxal) and ketonic (diacetyl), were reacted with the modified amino acid Nα‐acetyl‐L‐lysine (AcLys) in an attempt to establish structure/activity relationships for the reactivity of α‐dicarbonyls with the amine compound. Electrospray ionization mass spectrometry (ESI‐MS) combined with tandem mass spectrometry (MS/MS) and collision‐induced dissociation (CID) was used to identify and characterize reagents, intermediates and reaction products. The formation of dicarbonyl‐derived lysine dimers was observed exclusively. Especially, attention is drawn to alkyl‐ (asymmetrical dicarbonyl systems) and carboxyl‐ (glyoxal system) substituted imidazolium ions, at ring position 2.

The main differences observed in the reactions studied were related to the reactivity with the diimine intermediate. This intermediate can react either with a non‐hydrated dicarbonyl molecule at the aldehydic carbonyl, or with a mono‐hydrated one at the ketonic carbonyl, particularly for asymmetrical dicarbonyls. For 2‐carboxyl‐substituted imidazolium ion (glyoxal reaction), besides the usual keto–enol rearrangement from the diol group, an alternative reaction pathway (proton abstraction) appears to contribute also for the imidazolium ring‐closure process. Moreover, the formation of imidazolium ring structures can depend on several factors, namely, the presence (or absence) of electron donor substituents at the formed diol, the degree of stability of the new electrophile generated and/or the equilibrium concentration of the non‐ and mono‐hydrated dicarbonyl forms in solution, the last being particularly important for asymmetrical dicarbonyls.

The results reported reveal the complexity of reactivity as well as the diversity of imidazolium molecular structures. Copyright © 2006 John Wiley & Sons, Ltd.
Mass spectrometric characterization of lipid‐modified peptides for the analysis of acylated proteins
Authors: Hoffman Michael D. , Kast Juergen
Published: January 2006

The analysis of acylated proteins by mass spectrometry (MS) has largely been overshadowed in proteomics by the analysis of glycosylated and phosphorylated proteins; however, lipid modifications on proteins are proving to be of increasing importance in biomedical research. In order to identify the marker ions and/or neutral loss fragments that are produced upon collision‐induced dissociation, providing a means to identify the common lipid modifications on proteins, peptides containing an N‐terminally myristoylated glycine, a palmitoylated cysteine and a farnesylated cysteine were chemically synthesized. Matrix‐assisted laser desorption/ionization time‐of‐flight time‐of‐flight (MALDI‐TOF‐TOF), electrospray ionization quadrupole time‐of‐flight (ESI Q‐TOF), and electrospray ionization hybrid triple‐quadrupole/linear ion trap (ESI QqQLIT) mass spectrometers were used for the analysis. The peptide containing the N‐terminally myristoylated glycine, upon CID, produced the characteristic fragments a1 (240.4 Th) and b1 (268.4 Th) ions as well as a low‐intensity neutral loss of 210 Da (C14H26O). The peptides containing a farnesylated cysteine residue fragmented to produce a marker ion at a m/z of 205 Th (C15H25) as well as other intense farnesyl fragment ions, and a neutral loss of 204 Da (C15H24). The peptides containing a palmitoylated cysteine moiety generated neutral losses of 238 Da (C16H30O) and 272 Da (C16H32OS); however, no marker ions were produced. The neutral losses were more prominent in the MALDI‐TOF‐TOF spectra, whereas the marker ions were more abundant in the ESI QqQLIT and Q‐TOF mass spectra. Copyright © 2006 John Wiley & Sons, Ltd.
Collision‐induced dissociation studies of protonated ether—(H2O)n (n = 1–3) clusters
Authors: Goebbert Daniel J. , Chen Hao , Wenthold Paul G.
Published: January 2006

We have studied the protonated ether—(H2O)n (n = 1–3) complexes containing tetrahydrofuran, dimethyl, diethyl, dibutyl, and butylmethyl ethers using a flowing afterglow triple‐quadrupole mass spectrometer. Collision‐induced dissociation, CID, of all clusters with n = 1, 2 shows sequential water loss. The n = 3 cluster of dimethyl ether shows sequential water loss, while all other ether clusters display selective product formation. The CID spectra are interpreted based on known energetics, and theoretical studies of the dimethyl and diethyl ether systems. Copyright © 2006 John Wiley & Sons, Ltd.
Deuterium isotope effects observed during competitive binding chiral recognition electrospray ionization—mass spectrometry of cinchona alkaloid‐based systems
Authors: Schug Kevin A. , Maier Norbert M. , Lindner Wolfgang
Published: January 2006

Deuterium isotope effects are reported for binding between tert‐butylcarbamoyl‐quinine/quinidine chiral selectors and isotopomeric quasienantiomers of N‐(3,5‐dinitrobenzoyl)leucine measured using electrospray ionization‐mass spectrometry (ESI‐MS) and competitive binding. Evaluation of mixtures of each selector with one labeled and one unlabeled enantiomeric selectand of identical configuration showed a significant difference in measured ion abundances of diastereomeric complexes between the selector and each selectand. It was found that in some cases, the complex containing the nondeuterated selectand was 15% more abundant than its deuterated counterpart. On the basis of an assessment of solution‐ and gas‐phase isotope effects reported in the literature, a series of control experiments were performed to study the origin of the effects. On the basis of these measurements, our preliminary conclusion is that the differing gas‐phase physicochemical nature of the deuterated versus nondeuterated selectand represents the strongest contribution to the observed effect in this chiral molecular recognition system. Copyright © 2006 John Wiley & Sons, Ltd.
Fragmentation and skeletal rearrangements of 2‐arylylamino‐5‐aryl‐1,3,4‐oxadiazoles and their noncovalent complexes with cobalt cation and cyclodextrin studied by mass spectrometry
Authors: Frański Rafał , Gierczyk Błażej , Schroeder Grzegorz
Published: January 2006

Mass spectrometric fragmentation pathways of title compounds were studied by electron ionization (EI) and electrospray ionization (ESI) as methods of ion generation. To explain the observed complex skeletal rearrangements, tandem mass spectrometry, accurate mass measurement and isotope labeling (compounds containing one 13C atom in oxadiazole ring) were used. Loss of CO, N2 and H atoms under EI conditions led to the formation of 9,10‐dihydroacridine‐type ions, loss of NH3 under ESI conditions yielded the 4‐phenylphthalazinone‐type ions and the loss of HNCO under ESI conditions produced N‐arylamino‐benzonitrilium ions; however, this process can be affected by the electron‐donor/electron‐withdrawing properties of groups substituted at the phenyl rings. The ESI was used to study the complexes of the compounds with cobalt as well as with cyclodextrin. It was found that the compounds studied tend to form inclusion complexes with cyclodextrin of stoichiometry 1 : 1 and complexes of different stoichiometries with cobalt, although those of stoichiometry 6 : 1 and 4 : 1 are favored and the attachment of counter ion may stabilize the complexes 3 : 1 and 2 : 1. Copyright © 2006 John Wiley & Sons, Ltd.
Raman and IR spectral studies of L‐phenylalanine L‐phenylalaninium dihydrogenphosphate and DL‐phenylalaninium dihydrogenphosphate
Authors: Ravikumar B. , Rajaram R. K. , Ramakrishnan V.
Published: January 2006

The infrared (IR) and Raman spectra were recorded at room temperature for L‐phenylalanine, L‐phenylalaninium dihydrogenphosphate, and DL‐phenylalaninium dihydrogenphosphate, and the observed bands were assigned. In the first compound, a phenylalaninium cation and a zwitterionic L‐phenylalanine and in the latter compound two protonated DL‐phenylalaninium cations have been identified. Presence of NH···O and OH···O hydrogen bonds are revealed from the spectra. The symmetry of the dihydrogenphosphate anion is found to be retaining C2v symmetry in both crystals. Copyright © 2006 John Wiley & Sons, Ltd.
A novel ‘optimal’ exponential‐based integration algorithm for von‐Mises plasticity with linear hardening: Theoretical analysis on yield consistency, accuracy, convergence and numerical investigations
Authors: Artioli E. , Auricchio F. , Beirão da Veiga L.
Published: January 2006

In this communication we propose a new exponential‐based integration algorithm for associative von‐Mises plasticity with linear isotropic and kinematic hardening, which follows the ones presented by the authors in previous papers. In the first part of the work we develop a theoretical analysis on the numerical properties of the developed exponential‐based schemes and, in particular, we address the yield consistency, exactness under proportional loading, accuracy and stability of the methods. In the second part of the contribution, we show a detailed numerical comparison between the new exponential‐based method and two classical radial return map methods, based on backward Euler and midpoint integration rules, respectively. The developed tests include pointwise stress–strain loading histories, iso‐error maps and global boundary value problems. The theoretical and numerical results reveal the optimal properties of the proposed scheme. Copyright © 2006 John Wiley & Sons, Ltd.
Childhood acute lymphoblastic leukaemia in relation to population mixing around the time of birth in South Hungary
Authors: Nyári Tibor A. , Kajtár Pál , Bartyik Katalin , Thurzó László , Parker Louise
Published: January 2006

In a retrospective epidemiological study of 481,984 live births in South Hungary, we investigated whether higher levels of population mixing around the time of birth is a risk factor for acute lymphoblastic leukemia (ALL) under age 5 years. Poisson regression was used to investigate the relationship between risk of ALL and the population‐mixing index based on the number of incomers in each county district for each year, standardized to have a range of 0–1. Among all children, the risk of ALL increased significantly with increasing population mixing around the time of birth (trend across the range of 0–1 RR = 2.1 95% CI: 1.02–4.44). This effect was more marked for boys (RR = 3.1 95% CI: 1.13–8.51), which supports a sex‐specific effect of exposures on risk of ALL. Pediatric Blood Cancer © 2006 Wiley‐Liss, Inc.
Long‐lasting partial remission by Interferon‐alpha treatment in a child with essential thrombocythemia
Authors: Szegedi István , Benkő Ilona , Merő Gabriella , Prinzinger Ágota , Kappelmayer János , Kiss Csongor
Published: January 2006

Essential thrombocythemia (ET) is a clonal myeloproliferative disorder characterized by sustained thrombocytosis, isolated hyperplasia of megakaryocytic lineage, and association with thrombotic or bleeding episodes. It is extremely rare in childhood and frequently presents without evident clinical signs. We describe a 3‐year‐old girl with severe headache and dizziness suffering from ET, who was treated with Interferon‐alpha‐2a (IFN) based on the potent effect of this agent to inhibit myeloid colonies induced by phytohemagglutinin A stimulated leukocyte conditioned medium (PHA‐LCM). Bone‐marrow‐derived mononuclear cells of this patient did not exhibit spontaneous colony formation but responded to recombinant human (rh) erythropoietin (EPO), rh granulocyte‐colony stimulating factor (G‐CSF), granulocyte‐macrophage (GM)‐CSF, and stem‐cell factor in addition to PHA‐LCM. After 65 months of in vivo IFN treatment, the patient experienced a sustained partial remission with platelet counts varying between 400 and 600 × 103/µl. Pediatr Blood Cancer 2007;49:744–747. © 2006 Wiley‐Liss, Inc.
Adolescents with acute lymphoblastic leukaemia: Outcome on UK national paediatric (ALL97) and adult (UKALLXII/E2993) trials
Authors: Ramanujachar Ramya , Richards Sue , Hann Ian , Goldstone Anthony , Mitchell Christopher , Vora Ajay , Rowe Jacob , Webb David
Published: January 2006

Background

Adolescents with acute lymphoblastic leukaemia (ALL) have languished in the shadow of success of the outcome of therapy in childhood ALL. Their treatment has always been incorporated into either paediatric or adult clinical trials depending on the mode of referral and hence there is a need to address an age and risk specific strategy for improving the outcome of this neglected group of patients. This article has summarised the recent and updated retrospective comparative analysis of adolescents treated on the Medical Research Council (MRC) trials. This analysis adds further emphasis to the treatment approach and the merits and limitations of treatment of adolescents on paediatric and adult trials.

Methods

A retrospective comparative analysis of adolescents aged 15–17 years, treated on either MRC ALL97/revised 99 (n = 61), a randomised paediatric trial or UKALLXII/E2993 (n = 67), an adult trial, between 1997 and 2002 was undertaken.

Result

Results suggest a trend towards a superior outcome on paediatric trials. The 5‐year EFS on ALL97 was 65% (95% CI = 52–78%) and on UKALLXII/E2993 was 49% (95% CI = 37–61%;P = 0.01). Multivariate analysis allowing for age and Ph status, diminished the EFS difference, but confirmed a reduced rate of death in remission in patients managed on the paediatric protocol.

Conclusions

Despite limitations in the methodology, comparative studies including our MRC study suggest a consistent advantage for adolescents managed intensively on paediatric trials. Redefining age limits with risk‐based strategy and multi‐centre collaboration should be considered to improve the survival of young adults. Pediatr Blood Cancer 2007;48:254–261. © 2006 Wiley‐Liss, Inc.
Steady‐state and time‐resolved fluorescence studies of the intestinal fatty acid binding protein
Authors: Chattopadhyay Krishnananda , Frieden Carl
Published: January 2006

The intestinal fatty acid binding protein contains two tryptophan residues (Trp6 and Trp82) both of which have been shown by X‐ray and NMR methods to be buried in hydrophobic clusters. By using a combination of steady‐state and time‐resolved fluorescence experiments, we have deconvoluted the lifetime weighted contribution of each of the tryptophans to the steady‐state fluorescence quantum yield. While Trp82 has been implicated in an intermediate that appears at relatively high denaturant concentrations, the variation of the lifetime weighted contribution of Trp6 with urea or guanidium hydrochloride shows formation of an intermediate state at low concentrations of the denaturant before the actual unfolding starts. Trp82 did not show similar behavior. Fluorescence quenching experiments by acrylamide show that while Trp6 in the native protein is less solvent‐exposed, its accessibility is increased significantly at low urea concentration indicating that the early intermediate state is partially unfolded. Time‐resolved anisotropy experiments indicate that the volume of the partially unfolded intermediates is larger than the native protein and lead to the speculation that the last step of the protein folding might be the removal of solvent molecules from the protein. Proteins 2006. © 2006 Wiley‐Liss, Inc.
Estimation of survival functions in interval and right censored data using STD behavioural diaries
Authors: Harezlak Jaroslaw , Tu Wanzhu
Published: January 2006

In investigations of sexually transmitted diseases (STDs), true infection times are often either interval censored or right censored. For such data, reliable estimation of the survival function is difficult to obtain. In this research, we propose a resampling based method for the estimation of the survival function using auxiliary behavioural information provided by daily diaries. By imputing the unknown infection time from a list of sexual encounter times recorded in the diaries, the proposed procedure can be easily implemented using existing estimation procedures for right censored data. Our simulations show that the proposed procedure consistently outperforms the existingad hocestimation methods and produces smaller mean integrated squared errors (MISE). We illustrate this method by analysing infection data obtained from an ongoing STD investigation of adolescent females. Copyright © 2006 John Wiley & Sons, Ltd.
The age-dependent decline of attention deficit hyperactivity disorder: a meta-analysis of follow-up studies
Authors: FARAONE STEPHEN V. , BIEDERMAN JOSEPH , MICK ERIC
Published: January 2006

Background. This study examined the persistence of attention deficit hyperactivity disorder (ADHD) into adulthood.

Method. We analyzed data from published follow-up studies of ADHD. To be included in the analysis, these additional studies had to meet the following criteria: the study included a control group and it was clear from the methods if the diagnosis of ADHD included subjects who did not meet full criteria but showed residual and impairing signs of the disorder. We used a meta-analysis regression model to separately assess the syndromatic and symptomatic persistence of ADHD.

Results. When we define only those meeting full criteria for ADHD as having ‘persistent ADHD’, the rate of persistence is low, ~15% at age 25 years. But when we include cases consistent with DSM-IV's definition of ADHD in partial remission, the rate of persistence is much higher, ~65%.

Conclusions. Our results show that estimates of ADHD's persistence rely heavily on how one defines persistence. Yet, regardless of definition, our analyses show that evidence for ADHD lessens with age. More work is needed to determine if this reflects true remission of ADHD symptoms or is due to the developmental insensitivity of diagnostic criteria for the disorder.