bluuebunny/crossref_metadata_2025 huggingface dataset:
Special issue on neural repair
Authors: Kordower Jeffrey H.
Published: May 2009

Cover Illustration: Computer inverted image of tyrosine hydroxylase immunoreactive perikarya and fibers from a human fetal transplant case. The cells are vibrant, healthy, and cross from the graft to the host to provide new dopaminergic innervation to the host striatum. This example of plasticity in the human brain is striking and serves to highlight the types of studies undertaken by the membership of the ASNTR. Photo supplied by Jeffrey H. Kordower. J. Comp. Neurol., Volume 515, Number 1. J. Comp. Neurol. 515, 2009. © 2009 Wiley‐Liss, Inc.
Molecular Dynamics Simulations for a Pentacene Monolayer on Amorphous Silica
Authors: Della Valle Raffaele Guido , Venuti Elisabetta , Brillante Aldo , Girlando Alberto
Published: May 2009

Molecular dynamics simulations are presented for “bulklike” and “filmlike” monolayers of pentacene deposited on a slab of amorphous silica. The two simulated systems, which mainly differ in the tilt angle between the pentacene molecules and the silica surface, exhibit structural and energetic properties that match the available measurements. The bulklike monolayer, the structure of which corresponds to that of the low‐temperature polymorph of crystalline pentacene, is stable. The filmlike monolayer, in which the molecules are most closely normal to the surface, is instead thermodynamically metastable, in agreement with the experimental evidence.
Structure of Isolated Xanthone in the T1 State Obtained via Combined UV/IR Spectroscopy
Authors: Bartl Kristina , Funk Andreas , Gerhards Markus
Published: May 2009

In order to extend combined UV/IR spectroscopy to triplet states, xanthone has been chosen as a model system due to its efficient intersystem crossing (ISC). The IR/R2PI (resonant two‐photon ionisation) spectrum of the electronic ground state (S0) as well as the IR spectrum of the T1 state have been recorded in a supersonic jet. We show that the IR spectrum of a triplet state can be recorded subsequent to an ISC. In combination with DFT and TDDFT calculations, structural assignments are performed and geometrical changes are identified.
From research tool to routine test: CD38 monitoring in HIV patients
Authors: Coetzee Lindi M. , Tay Szun Szun , Lawrie Denise , Janossy George , Glencross Deborah K.
Published: May 2009

Background:

CD38 expression on CD8+ T lymphocytes in HIV‐infected patients is monitored by flow cytometry (FCM). There is however no consensus re CD38 protocols, analyses or result reporting within/between laboratories. Internal quality control measures (QC) were established for a standardized CD38 protocol and a system proposed for reporting CD38 fluctuation in longitudinal HIV+ patient monitoring.

Methods:

A single‐platform (SP) CD38/CD8 protocol was “piggy‐backed” onto the standardized “panleucogating” CD45/CD4+ protocol. A weekly QC was established to monitor instrument stability (FlowSET™) and absolute cell count accuracy and reproducibility (stabilized blood product, Immuno‐Trol™). The Mean Fluorescence Intensity (MFI) of CD38 expression on CD8+‐lymphocytes was monitored on both stabilized blood and HIV‐control samples. Linearized MFI values were determined from biological controls, i.e. healthy donor monocytes and granulocytes, and tested as a method of reporting CD38 expression on selected HIV+ patients on ART.

Results:

The CD45/CD4/CD8/CD3 method for lymphocyte enumeration compared well with the CD38 protocol (CD45/CD4/CD8/CD38) with excellent similarity (±100%) and precision for absolute CD4 and CD8 counts (CVs < 5%). Fluorosphere MFI‐ (FlowSet™, FlowCount™) and color compensation values were exceptionally stable over time. CD38 MFI values established on monocytes as biological control was 4.0 and <2.0 for HIV‐control lymphocytes.

Conclusions:

Monitoring FCM with fluorosphere MFI values, color compensation, and biological controls, can ensure that CD38 analyses are technologically stable. Flow cytometry is thus the preferred method to monitor fluctuations in CD38 MFI (CD38 molecules/cell) associated with HIV‐disease progression and/or response to ART and has potential for application across instruments and centers. © 2009 Clinical Cytometry Society
GSK3β affects apical–basal polarity and cell–cell adhesion by regulating aPKC levels
Authors: Colosimo Pamela F. , Liu Xiaoping , Kaplan Nicole A. , Tolwinski Nicholas S.
Published: May 2009

The dynamic rearrangement of cell–cell contacts is required for the establishment of functional epithelial cell sheets. However, the signaling pathways and cellular mechanisms that initiate and maintain this polarity are not well understood. We show that loss of the Wnt signaling component GSK3β results in increased levels of aPKC and leads to defects in apical–basal polarity. We find that GSK3β directly phosphorylates aPKC, which likely promotes its ubiquitin‐mediated proteosomal degradation. aPKC increases the levels of Armadillo and stabilizes adherens junctions. These results suggest that the Wnt pathway component GSK3β regulates the polarity determinant aPKC, which in turn affects cell–cell contacts during the development of polarized tissues. Developmental Dynamics 239:115–125, 2010. © 2009 Wiley‐Liss, Inc.
The non‐conserved C‐terminal segments of Sine Oculis Homeobox (SIX) proteins confer functional specificity
Authors: Weasner Brandon P. , Kumar Justin P.
Published: May 2009

The Sine Oculis Homeobox (SIX) proteins play critical roles in organogenesis and are defined by the presence of two evolutionarily conserved functional motifs: a homeobox DNA binding domain and the SIX protein–protein interaction domain. Members of this transcription factor family can be divided into three subgroups: Six1/2, Six4/5, and Six3/6. This partitioning is based mainly on protein sequence similarity and genomic architecture, and not on specificities of DNA binding or binding partners. In fact, it is well demonstrated that members of the different subgroups can bind to and activate common transcriptional targets as well as form biochemical complexes with communal binding partners. Here we report that the C‐terminal segment, which is not conserved across different SIX subfamilies, may serve to functionally distinguish individual SIX proteins. In particular, we have dissected the C‐terminal region of Optix, the Drosophila ortholog of mammalian Six3/6, and identified three regions that distinguish Optix from Sine Oculis, the fly homolog of Six1/2. Two of these regions have been preserved in all Six3/6 family members while the third section is present only within Optix proteins in the Drosophilids. The activities of these regions are required, in unison, for Optix function. We suggest that biochemical/functional differences between members of large protein families as well as proteins encoded by duplicate genes can, in part, be attributed to the activities of nonconserved segments. Finally, we demonstrate that a subset of vertebrate SIX proteins has retained the ability to function during normal fly eye development but have lost the ability to induce the formation of ectopic eyes. genesis 47:514–523, 2009. © 2009 Wiley‐Liss, Inc.
Characterization of teleost Mdga1 using a gene‐trap approach in medaka (Oryzias latipes)
Authors: Sano Shinya , Takashima Shigeo , Niwa Hitomi , Yokoi Hayato , Shimada Atsuko , Arenz Alexander , Wittbrodt Joachim , Takeda Hiroyuki
Published: May 2009

MAM domain containing glycosilphosphatidilinositol anchor 1 (MDGA1) is an IgCAM protein present in many vertebrate species including humans. In mammals, MDGA1 is expressed by a subset of neurons in the developing brain and thought to function in neural cell migration. We identified a fish ortholog of mdga1 by a gene‐trap screen utilizing the Frog Prince transposon in medaka (Japanese killifish, Oryzias latipes). The gene‐trap vector was inserted into an intronic region of mdga1 to form a chimeric protein with green fluorescent protein, allowing us to monitor mdga1 expression in vivo. Expression of medaka mdga1 was seen in various types of embryonic brain neurons, and specifically in neurons migrating toward their target sites, supporting the proposed function of MDGA1. We also isolated the closely related mdga2 gene, whose expression partially overlapped with that of mdga1. Despite the fact that the gene‐trap event eliminated most of the functional domains of the Mdga1 protein, homozygous embryos developed normally without any morphological abnormality, suggesting a functional redundancy of Mdga1 with other related proteins. High sequential homology of MDGA proteins between medaka and other vertebrate species suggests an essential role of the MDGA gene family in brain development among the vertebrate phylum. genesis 47:505–513, 2009. © 2009 Wiley‐Liss, Inc.
Transgenic analysis of the physiological functions of Mahogunin ring finger‐1 isoforms
Authors: Jiao Jian , Kim Hae Young , Liu Roy R. , Hogan Carolyn A. , Sun Kaihua , Tam Lori Mon , Gunn Teresa M.
Published: May 2009

Mahogunin Ring Finger‐1 (Mgrn1) null mutant mice have a pleiotropic phenotype that includes the absence of yellow hair pigment, abnormal head shape, reduced viability, and adult‐onset spongiform neurodegeneration. Mgrn1 encodes a highly conserved E3 ubiquitin ligase with four different isoforms which are differentially expressed and predicted to localize to different subcellular compartments. To test whether loss of specific isoforms causes different aspects of the mutant phenotype, we generated transgenes for each isoform and bred them onto the null mutant background. Mice expressing only isoform I or III appeared completely normal. Isoform II rescued or partially rescued the mutant phenotypes, whereas isoform IV had little or no effect. Our data show that different Mgrn1 isoforms are not functionally equivalent in vivo and that the presence of only isoform I or III is sufficient for normal development, pigmentation, and neuronal integrity. genesis 47:524–534, 2009. © 2009 Wiley‐Liss, Inc.
Personality dimensions among women with an eating disorder: Towards reconceptualizing DSM
Authors: Tasca Giorgio A. , Demidenko Natasha , Krysanski Valerie , Bissada Hany , Illing Vanessa , Gick Mary , Weekes Kirsti , Balfour Louise
Published: May 2009

Objective

To evaluate the incremental validity of a dimensional assessment of personality, after controlling for diagnostic category, in accounting for meaningful variation in eating disorder attitudes and behaviours and in current affective distress among a clinical sample of eating disordered women.

Methods

244 treatment seeking eating disordered women and 116 non‐eating disordered women were assessed with the NEO five factor inventory (NEO‐FFI), and with measures of eating disorder attitudes and of affective distress using a cross sectional design.

Results

As predicted, differences were found between eating disordered and non‐eating disordered women on several NEO‐FFI scales, which provided a context for subsequent analyses. NEO‐FFI scales accounted for meaningful variation in eating disordered attitudes and behaviours as well as in levels of current affective distress over and above DSM‐IV diagnostic category.

Conclusion

A flexible approach to diagnosis, which includes personality dimensions along with a description of eating disorder symptoms, may result in a more inclusive and useful diagnostic scheme for treating women with eating disorders. Copyright © 2009 John Wiley & Sons, Ltd and Eating Disorders Association.
Influence of a single nucleotide polymorphism in the P1 promoter of the furin gene on transcription activity and hepatitis B virus infection #
Authors: Lei Rui Xiang , Shi Hong , Peng Xiao Mou , Zhu Yin Hong , Cheng Jie , Chen Gui Hua
Published: May 2009

Hepatitis B e antigen (HBeAg) is a viral strategy of immune response evasion associated with hepatitis B virus (HBV) persistence. Spontaneous HBeAg seroconversion is usually accompanied by liver disease remission. Unfortunately, this goal is difficult to achieve and requires expensive and time-consuming treatment. Furin, a proprotein convertase, is involved in HBeAg maturation and is therefore a potential therapeutic target or indicator for predicting disease progression and antiviral response. Here we demonstrate that healthy Han Chinese from southern China (an endemic area of HBV infection) harbor a common single nucleotide polymorphism (SNP; −229 C/T) in a 1268-bp region of the P1 promoter of the furin gene [FES upstream region (Fur)]. A luciferase reporter gene assay showed that transcription activity is about 3 times higher in allele T carriers than in allele C carriers of this SNP. Allele T includes a suboptimal transcription factor NF-E2 [i.e., nuclear factor (erythroid-derived 2)]–binding motif according to bioinformatics and studies using site-directed mutagenesis. We also observed that individuals carrying allele T were more likely to become persistently infected. When persistently infected patients were divided into subgroups according to recent guidelines and HBeAg-defective virus infection was taken into account, patients with allele T or genotype TT had a decreased likelihood of HBeAg seroconversion or an increased likelihood of progressing to HBeAg-negative chronic hepatitis B or liver cirrhosis if accompanied by HBeAg-defective virus infection. Conclusion: The common SNP in the P1 promoter of the Fur gene affects furin transcription activity and HBV infection outcome, possibly by increasing furin messenger RNA expression, and this suggests that furin is a potential therapeutic target and that this SNP is a potential predictor of disease progression or therapeutic response. (Hepatology 2009.)
RETRACTED:ESTIMATION OF IRRIGATION REQUIREMENTS FOR SOME CROPS IN SOUTHERN QUEBEC USING CROPWAT
Authors: Doria R. O. , Madramootoo C. A.
Published: May 2009

The following article from Irrigation and Drainage, Estimation of irrigation requirements for some crops in Southern Quebec using CROPWAT by R. O. Doria and C. A. Madramootoo, published online on 6 May 2009 in Wiley Online Library (wileyonlinelibrary.com), has been retracted by agreement between the authors, the journal Chair of the Editorial Board, Prof. Bart Schultz and John Wiley & Sons Ltd. The retraction has been agreed due to problems with the model simulation that potentially invalidate the conclusions.
Villains or heroes? Farmers' adjustments to water scarcity
Authors: Molle François , Venot Jean‐Philippe , Lannerstad Mats , Hoogesteger Jaime
Published: May 2009

Although farmers are often seen as wasting water and getting a disproportionate share of water, irrigation is losing out in the competition for water with other sectors. In cases of drought, water restrictions are overwhelmingly imposed on irrigation while other activities and domestic supply are only affected in cases of very severe shortage. All over the world, farmers have been responding to the challenge posed by both short‐ and long‐term declining water allocations in many creative ways, but these responses have often been overlooked by policy makers. This paper examines how farmers have adapted to water scarcity in six different river basins of Asia and the Middle East. It inventories the different types of adjustments observed and shows not only their effectiveness in offsetting the drop in supply but also their costs to farmers and to the environment and their contribution to basin closure. The conclusion calls for a better recognition of the efforts made by the irrigation sector to respond to water challenges and of its implications in terms of reduced scope for efficiency gains in the irrigation sector. Copyright © 2009 John Wiley & Sons, Ltd.
In vitro/in vivo biocompatibility and mechanical properties of bioactive glass nanofiber and poly(ε‐caprolactone) composite materials
Authors: Jo Ji‐Hoon , Lee Eun‐Jung , Shin Du‐Sik , Kim Hyoun‐Ee , Kim Hae‐Won , Koh Young‐Hag , Jang Jun‐Hyeog
Published: May 2009

In this study, a poly(ε‐caprolactone) (PCL)/bioactive glass (BG) nanocomposite was fabricated using BG nanofibers (BGNFs) and compared with an established composite fabricated using microscale BG particles. The BGNFs were generated using sol–gel precursors via the electrospinning process, chopped into short fibers and then incorporated into the PCL organic matrix by dissolving them in a tetrahydrofuran solvent. The biological and mechanical properties of the PCL/BGNF composites were evaluated and compared with those of PCL/BG powder (BGP). Because the PCL/BG composite containing 20 wt % BG showed the highest level of alkaline phosphatase (ALP) activity, all evaluations were performed at this concentration except for that of the ALP activity itself. In vitro cell tests using the MC3T3 cell line demonstrated the enhanced biocompatibility of the PCL/BGNF composite compared with the PCL/BGP composite. Furthermore, the PCL/BGNF composite showed a significantly higher level of bioactivity compared with the PCL/BGP composite. In addition, the results of the in vivo animal experiments using Sprague–Dawley albino rats revealed the good bone regeneration capability of the PCL/BGNF composite when implanted in a calvarial bone defect. In the result of the tensile test, the stiffness of the PCL/BG composite was further increased when the BGNFs were incorporated. These results indicate that the PCL/BGNF composite has greater bioactivity and mechanical stability when compared with the PCL/BG composite and great potential as a bone regenerative material. © 2009 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2009
Is ceramic‐on‐ceramic squeaking phenomenon reproducible in vitro? A long‐term simulator study under severe conditions
Authors: Affatato S. , Traina F. , Mazzega‐Fabbro C. , Sergo V. , Viceconti M.
Published: May 2009

Clinical and in vitro studies on ceramic hip prostheses correlate cup implant position with hip noise, ceramic wear, or ceramic liner damage. A ceramic cup malposition could lead to edge load, ceramic head wear, and squeaking. A noise of a ceramic hip could also be correlate with implant instability and liner damage. Aim of this study was to investigate the long‐term wear behavior of 12 commercial alumina‐on‐alumina bearings under severe conditions: different angles of inclination (23°, 45°, and 63°) and the addition of third body particles (titanium and alumina powder) to address the effective role of cup position and ceramic particles on wear and hip noise. The study was performed using a 12‐stations hip joint wear simulator (Shore Western, Monrovia) under bovine calf serum used as lubricant. Wear was evaluated by gravimetric method and the piezo‐spectroscopic technique was used to evaluate the residual stress of the ceramic components and correlate this to the weight loss. After eight million cycles, we found that the inclination of the cup (63° in this study) was the most disadvantaged and it was correlated with a hip noise. Gravimetric measurements showed higher wear than the other configurations and these results were in agreement with the Photoluminescence investigation. In particular, the results obtained in this work revealed a residual stress state greater not only with respect to the other angles of inclination but also to two retrieved alumina acetabular cups with a 10 years follow‐up. © 2009 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2009
Unified QSAR & network‐based computational chemistry approach to antimicrobials. II. Multiple distance and triadic census analysis of antiparasitic drugs complex networks
Authors: Prado‐Prado Francisco J. , Ubeira Florencio M. , Borges Fernanda , González‐Díaz Humberto
Published: May 2009

In the previous work, we reported a multitarget Quantitative Structure‐Activity Relationship (mt‐QSAR) model to predict drug activity against different fungal species. This mt‐QSAR allowed us to construct a drug–drug multispecies Complex Network (msCN) to investigate drug–drug similarity (González‐Díaz and Prado‐Prado, J Comput Chem 2008, 29, 656). However, important methodological points remained unclear, such as follows: (1) the accuracy of the methods when applied to other problems; (2) the effect of the distance type used to construct the msCN; (3) how to perform the inverse procedure to study species–species similarity with multidrug resistance CNs (mdrCN); and (4) the implications and necessary steps to perform a substructural Triadic Census Analysis (TCA) of the msCN. To continue the present series with other important problem, we developed here a mt‐QSAR model for more than 700 drugs tested in the literature against different parasites (predicting antiparasitic drugs). The data were processed by Linear Discriminate Analysis (LDA) and the model classifies correctly 93.62% (1160 out of 1239 cases) in training. The model validation was carried out by means of external predicting series; the model classified 573 out of 607, that is, 94.4% of cases. Next, we carried out the first comparative study of the topology of six different drug–drug msCNs based on six different distances such as Euclidean, Chebychev, Manhattan, etc. Furthermore, we compared the selected drug–drug msCN and species–species mdsCN with random networks. We also introduced here the inverse methodology to construct species–species msCN based on a mt‐QSAR model. Last, we reported the first substructural analysis of drug–drug msCN using Triadic Census Analysis (TCA) algorithm. © 2009 Wiley Periodicals, Inc. J Comput Chem 2010
λ‐Dynamics free energy simulation methods
Authors: Knight Jennifer L. , Brooks Charles L.
Published: May 2009

Free energy calculations are fundamental to obtaining accurate theoretical estimates of many important biological phenomena including hydration energies, protein‐ligand binding affinities and energetics of conformational changes. Unlike traditional free energy perturbation and thermodynamic integration methods, λ‐dynamics treats the conventional “λ” as a dynamic variable in free energy simulations and simultaneously evaluates thermodynamic properties for multiple states in a single simulation. In the present article, we provide an overview of the theory of λ‐dynamics, including the use of biasing and restraining potentials to facilitate conformational sampling. We review how λ‐dynamics has been used to rapidly and reliably compute relative hydration free energies and binding affinities for series of ligands, to accurately identify crystallographically observed binding modes starting from incorrect orientations, and to model the effects of mutations upon protein stability. Finally, we suggest how λ‐dynamics may be extended to facilitate modeling efforts in structure‐based drug design. © 2009 Wiley Periodicals, Inc. J Comput Chem 2009
Exploration of density functional methods for one‐electron reduction potential of nitrobenzenes
Authors: Zubatyuk Roman I. , Gorb Leonid , Shishkin Oleg V. , Qasim Mo , Leszczynski Jerzy
Published: May 2009

Performance of the set of density functional approaches for calculation of one‐electron reduction potentials of nitroaromatic compounds was investigated. To select the most precise and affordable method, we selected a set of model molecules and investigated effects of basis set, density functional, and solvation model on the calculation of reduction potentials. It was found that the mPWB1K/TZVP method provides the most accurate gas phase electron affinity values (RMS error is 0.1 eV). This method in conjunction with the PCM (Bondi) method yields also the most accurate difference in solvation energies of neutral oxidized form and anion‐radical reduced form. The final E0 values were calculated with RMS error of 0.10 V, compared with experimental values. © 2009 Wiley Periodicals, Inc. J Comput Chem 2010
Crystal contacts as nature's docking solutions
Authors: Krissinel Evgeny
Published: May 2009

The assumption that crystal contacts reflect natural macromolecular interactions makes a basis for many studies in structural biology. However, the crystal state may correspond to a global minimum of free energy where biologically relevant interactions are sacrificed in favor to unspecific contacts. A large‐scale docking experiment was performed to assess the extent of misrepresentation of natural (in‐solvent) protein dimers by crystal packing. As found, the failure rate of docking may be quantitatively interpreted if both calculation errors and misrepresentation effects are taken into account. The failure rate analysis is based on the assumption that crystal structures reflect thermodynamic equilibrium between different dimeric configurations. The analysis gives an estimate of misrepresentation probability, which suggests that weakly bound complexes with KD ≥ 100 μM (some 20% of all dimers in the PDB) have higher than 50% chances to be misrepresented by crystals. The developed theoretical framework is applicable in other studies, where experimental results may be viewed as snapshots of systems in thermodynamic equilibrium. © 2009 Wiley Periodicals, Inc. J Comput Chem 2010
Drug efficiency indices for improvement of molecular docking scoring functions
Authors: García‐Sosa Alfonso T. , Hetényi Csaba , Maran Uko
Published: May 2009

A dataset of protein‐drug complexes with experimental binding energy and crystal structure were analyzed and the performance of different docking engines and scoring functions (as well as components of these) for predicting the free energy of binding and several ligand efficiency indices were compared. The aim was not to evaluate the best docking method, but to determine the effect of different efficiency indices on the experimental and predicted free energy. Some ligand efficiency indices, such as ΔG/W (Wiener index), ΔG/NoC (number of carbons), and ΔG/P (partition coefficient), improve the correlation between experimental and calculated values. This effect was shown to be valid across the different scoring functions and docking programs. It also removes the common bias of scoring functions in favor of larger ligands. For all scoring functions, the efficiency indices effectively normalize the free energy derived indices, to give values closer to experiment. Compound collection filtering can be done prior or after docking, using pharmacokinetic as well as pharmacodynamic profiles. Achieving these better correlations with experiment can improve the ability of docking scoring functions to predict active molecules in virtual screening. © 2009 Wiley Periodicals, Inc. J Comput Chem 2010
PAPER—Accelerating parallel evaluations of ROCS
Authors: Haque Imran S. , Pande Vijay S.
Published: May 2009

Modern graphics processing units (GPUs) are flexibly programmable and have peak computational throughput significantly faster than conventional CPUs. Herein, we describe the design and implementation of PAPER, an open‐source implementation of Gaussian molecular shape overlay for NVIDIA GPUs. We demonstrate one to two order‐of‐magnitude speedups on high‐end commodity GPU hardware relative to a reference CPU implementation of the shape overlay algorithm and speedups of over one order of magnitude relative to the commercial OpenEye ROCS package. In addition, we describe errors incurred by approximations used in common implementations of the algorithm. © 2009 Wiley Periodicals, Inc. J Comput Chem 2010
Effluent treatment using a bipolar electrochemical reactor with rotating cylinder electrodes of woven wire meshes
Authors: Grau Javier M , Bisang José M
Published: May 2009

BACKGROUND: The behaviour of a bipolar electrochemical reactor consisting of one or more rotating cylinder electrodes of woven wire meshes is reported using copper and cadmium deposition from dilute solutions as test reactions.

RESULTS: The best performance related to electrode number was determined for copper deposition and was achieved by an arrangement with two bipolar electrodes, for which the conversion in a single pass was approximately 47%. The specific energy consumption was 3.27 kWh kg−1 with a normalised space velocity of 23.05 h−1. The copper powder obtained showed a nodular and dendritic surface morphology. This reactor configuration was also analysed for cadmium deposition, in which hydrogen evolution takes place simultaneously as a side cathodic reaction, considering the effect of flow rate and total current. The maximum conversion per pass for cadmium removal was 38.91%. In this case the reactor with two bipolar electrodes showed a performance similar to that of a monopolar reactor operated at a rotation speed three times higher.

CONCLUSION: A continuous electrochemical reactor with two rotating bipolar electrodes of woven wire meshes presents a good performance for copper or cadmium removal from dilute solutions. Copyright © 2009 Society of Chemical Industry
Microscopic studies of the influence of main exposure time on parameters of flexographic printing plate produced by digital thermal method
Authors: Harri Liliya
Published: May 2009

The digital thermal technology of producing flexographic printing plates from photopolymer plates is one of the newest technologies. This technology allows to develop flexographic plates without the use of any solvent. The process of producing flexographic printing plates by the digital thermal method consists of several main stages: back exposure, laser exposure, main exposure, thermal development, post exposure, and light finishing. The studies carried out with the use of optical stereoscopic microscopy allowed to determine the effect of time of main exposure to ultraviolet radiation on the dot area, diameter, and edge factor of halftone dots reproduced on flexographic printing plate produced by the digital thermal method, as well as on the quality of reproducing the surface and on the profiles of free‐standing printing microelements. The results of the microscopic studies performed have allowed to define the criteria of establishing optimum time of main exposure of photopolymer plates used in the digital thermal technology of producing flexographic printing plates. A precise definition of the criteria for determining the optimum time of main exposure will enable to reduce the time‐consuming control tests and to eliminate errors in both the process of manufacturing flexographic printing plates and in the printing process carried out with the use of such plates. Microsc. Res. Tech., 2009. © 2009 Wiley‐Liss, Inc.
Nitrogen heterocyclic analogs of polyaryls
Authors: Buu‐Hoï N. P. , Périn F. , Jacquignon P.
Published: May 2009

Nitrogen heterocyclic analogs of polyaryls, derived from pyridine, quinoline, benzo[h]‐quinoline, indole, indolizine, and imidazo[1,2‐alpyridine, have been prepared from 1,4‐diacetyl‐ and 1,3,5‐triacetylbenzene and 2,6‐diacetylpyridine, for study of their physical, chemical and biological properties.
Aromaticity in heterocyclic systems III. The structure and proton magnetic resonance spectra of certain imidazo[1,2‐a]pyridines
Authors: Paolini John P. , Robins Roland K.
Published: May 2009

A number of improved laboratory procedures for the synthesis of derivatives ofimidazo‐[1,2‐alpyridines are reported. These methods have been employed for the preparation of 5‐chloroimidazo[1,2‐alpyridine (IX), 5‐aminoimidazo[1,2‐a]pyridine (IV), 2‐methyl and 2,3‐dimethyl‐5‐aminoimidazo[1,2‐a]pyridine. The proton magnetic resonance spectra of imidazo[1,2‐a]pyridine (I) have been studied and the bands assigned by a comparison of spectral patterns of simple derivatives. The proton magnetic resonance spectra were then utilized to assign predominant tautomeric structures to imidazo[1, 2‐a]‐2‐pyridone (IIIb), imidazo[1,2‐a]‐(1H)‐5‐pyridone (VIIb) and 5‐aminoimidazo‐[1, 2‐alpyridine (IV). The synthesis of imidazo[1,2‐a]‐(1H)‐5‐pyridone (VII) was accomplished from 5‐chloro‐imidazo[1, 2‐alpyridine (IX) via 5‐benzyloximidazo[1,2‐a]pyridine (X) which was debeneylated catalytically to yield VII. Bromoacetaldehyde and 2‐amino‐4‐chloropyridine gave 7‐chloroimidazo[1,2‐a]pyridine.
1,2,3‐Thiadiazoles as potential antineoplastic agents. I. Synthesis of novel 4‐monosubstituted and 4,5‐disubstituted derivatives
Authors: Looker J. H. , Wilson Leon W.
Published: May 2009

1,2,3‐Thiadiazole‐4‐carboxylic acid (IV) has been synthesized by oxidation of 5‐(2‐furyl)‐1,2,3‐thiadiazole‐4‐carboxylic acid (IIb), and converted via the acid chloride (V) to the amide (VI), ethyl ester (VII) and azide (IX). Rearrangement of the azide (IX) in ethanol led to ethyl N‐(1,2,3‐thiadiazol‐4‐yl)carbamate (X) and in benzene or toluene to a complex substance, possibly N,N,N‐tris‐(1,2,3‐thiadiazol‐4‐yl)‐isocyanurate (XI). Ethyl 5‐phenoxy‐1,2,3‐thiadiazole‐4‐carboxylate (XIII), prepared from ethyl (phenoxy‐acetyl)diazoacetate (XII), has been converted to ethyl 5‐formyl‐1,2,3‐thiadiazole‐4‐car‐boxylate methyl phenyl acetal (XVI) via the α ‐halo ether (XIV). The acetal (XVI) underwent partial hydrolysis in dilute acid to yield ethyl 5‐formyl‐1,2,3‐thiadiazole‐4‐car‐boxylate phenyl hemiacetal (XVII) as an oil. Vacuum distillation of XVII gave ethyl 5‐formyl‐1,2,3‐thiadiazole‐4‐carboxylate (XVIII) as an oil. The aldehyde XVIII, but not the hemiacetal XVII, formed a crystalline oxime (XIX) with hydroxylamine.
Naphtho[2,3‐a]quinolizinium derivatives
Authors: Doolittle R. E. , Bradsher C. K.
Published: May 2009

The alkylation of 2‐acetonylpyridines with β‐phenylethyl bromides leads to ketones which may be cyclized to 1‐methyl‐2‐(2‐pyridyl)‐3,4‐dihydronaphthalenes. Aromatization of the dihydronaphthalenes followed by quaternization with chloroacetaldoxime affords salts which may be cyclized to yield the title compounds.
5,6‐Dihydro‐4 H,1,3,4‐oxadiazines. IV. Further studies
Authors: Trepanier D. L. , Spracmanis V. , Tharpe D. S. , Krieger P. E.
Published: May 2009

The scope of the acid‐catalyzed cyclodehydration of 2‐(β‐hydroxyalkyl)carboxylic acid hydrazides into 5, 6‐dihydro‐4H‐1, 3, 4‐oxadiazines has been extended through the use of acidic reagents other than concentrated sulfuric and polyphosphoric acids. Additional data are presented which corroborate previously proposed mechanisms of this reaction.
Nuclear magnetic resonance studies of heteroaromatic systems. Methyl coupling of 2‐substituted picolines, 2‐pyridones and 2‐pyridthiones
Authors: Bell Charles L. , Egan Richard S. , Bauer Ludwig
Published: May 2009

The proton magnetic resonance spectra of all the 2‐amino‐, 2‐chloro‐, 2‐nitropicolines were determined. Long‐range coupling of the methyl groups to all available ortho (four bonds) and para (six bonds) ring protons was found in these picolines. The p.m.r. spectra of all of the ring methyl substituted 2‐pyridones and 2‐pyridthiones were analyzed. In 4‐ and 5‐methyl‐2‐pyridones and the corresponding thiones, selective ring coupling was observed to only one ortho ring proton, viz., to H‐3 and H‐6 respectively. However, in 3‐ and 6‐methyl‐2‐pyridones and analogous thiones, long‐range coupling was visible to both ortho and para ring protons. These long‐range spin‐spin interactions are interpreted in terms of the structures of 2‐pyridones and their thione analogs.
A new synthesis of benzimidazoles and aza‐analogs
Authors: Ridley H. F. , Spickett R. G. W. , Timmis G. M.
Published: May 2009

A new procedure for the preparation of benzimidazoles and aza‐analogs from o‐diamines and aldehyde bisulfite adducts is described.
Cinnoline chemistry. XII. The synthesis of 6‐fluoro‐4‐methylcinnoline and other cinnolines as potential antitumor agents
Authors: Castle Raymond N. , Adachi Kikuo , Guither William D.
Published: May 2009

6‐Fluoro‐4‐methylcinnoline (IX) has been synthesized in eight steps from 4‐fluoroaniline. A series of styryl and pyridylethenyl cinnolines have been prepared from 6‐fluoro‐4‐methylcinnoline (IX), 4‐methylcinnoline and 4‐methylcinnoline‐2‐oxide. Furthermore, a series of 4‐substituted benzylthiocinnolines have been prepared.
Thiocyanation of amino‐2‐methylbenzothiazoles
Authors: Grandolini Giuliano , Ricci Adolfo , Martani Alfio , Mezzetti Tarcisio
Published: May 2009

Thiocyanation of the four amino‐2‐methylbenzothiazole isomers has been studied: in three of these the thiocyano group is oriented ortho to the amino group and consequently three new angular benzobisthiazoles have been obtained. The 7‐thiocyano derivative was obtained from 4 ‐ amino ‐ 2 ‐ methylbenzothiazole. The structure of the benzobis‐heterocycles has been confirmed by NMR spectroscopy.
Reaction of the thiolsulfonate group with the aromatic nucleus: A new ring closure
Authors: Dunbar Joseph E. , Tarnowski Betty H.
Published: May 2009

The double ring closure of N,N‐bis[2‐ (alkyl‐ or arylsulfonylthio)ethyl]anilines to form 2,3,5,6‐tetrahydro[1,4]thiazino[4,3,2‐de][1,4]benzothiazines, a new ring system, is reported. The effects of various benzene ring substituents upon the ring closure are described.
New synthesis routes to 2‐halopyridines. III. 2‐fluoropyridine
Authors: Boudakian Max M.
Published: May 2009

The solvent‐free fluorination of 2‐chloropyridine (III) with alkali metal fluorides and bifluorides was investigated. While complete degradation occurred with potassium fluoride at 315°, the use of potassium bifluoride under identical conditions provided a 74% yield of 2‐fluoro‐pyridine (II). Sodium bifluoride gave only a 3.5% yield of the desired product. These results are discussed in the light of: activation of the substrate, properties of the fluorinating agents, and the stability of 2‐fluoropyridine.
Geometrical isomerism and photochemical behaviour of α‐substituted 2 and 4‐styrylpyridines
Authors: Galiazzo G. , Bortolus P. , Cauzzo G. , Mazzucato U.
Published: May 2009

α‐Methyl and α‐phenyl substituted 2 and 4‐styrylpyridines were prepared by classical routes. The geometrical isomers were separated and characterized on the basis of their U.V. absorption spectra and/or of their behaviour under U.V. irradiation which led to photoisomerization and photocyclization products. The last photoreaction, in the case of α‐phenyl derivatives, gave pyridyl‐substituted phenanthrenes and phenyl‐substituted azaphenanthrenes which were isolated and characterized.

Spectral, chromatographic and physical properties of trans and cis derivatives and related photocyclization products are given as well as some kinetic data for the photochemical reactions.
The synthesis of 5,6‐dihydro‐6‐methylthiazolo‐[2,3‐b] [1,3] benzodiazepines, 2,3,10,11‐tetrahydro‐10‐methyl‐1H‐cyclopenta[4,5] thiazolo[2,3‐b] [1,3] benzodiazepine, and 7,8,9,10,12,13‐hexahydro‐13‐methylbenzothiazolo[2,3‐b] [1,3]‐benzodiazepine via 1,3,4,5‐tetrahydro‐5‐methyl‐2H‐1,3‐benzodiazepine‐2‐thione
Authors: Elslager Edward F. , Worth Donald F. , Perricone S. C.
Published: May 2009

Catalytic reductive scission of 4‐methylcinnoline (V) with Raney nickel afforded o‐amino‐β‐methylphenethylamine (IV) in 57% yield. Treatment of IV with carbon disulfide followed by thermal cyclization of the product furnished 1,3,4,5‐tetrahydro‐5‐methyl‐2H‐1,3‐benzodiazepine‐2‐thione (III). Reaction of III with ethyl chloroacetate, ethyl 2‐bromohexanoate, ethyl 2‐chloroacetoacetate, 2‐bromo‐2′‐methoxyacetophenone, and 2‐bromoacetophenone provided a series of substituted 5,6‐dihydro‐6‐methylthiazolo[2,3‐b][1,3]benzodiazepines. Condensation of III with 2‐chlorocyclopentanone and 2‐chlorocyclohexanone gave 2,3,10,11‐tetrahydro‐10‐methyl‐1H‐cyclopenta[4,5]thiazolo[2,3‐b][1,3]benzodiazepine and 7,8,9,10,12,13‐hexahydro‐13‐methylbenzothiazolo[2,3‐b][1,3]benzodiazepine, respectively. Structure assignments are discussed. None of the compounds possessed appreciable biological activity.
Compounds in the pyrrolo[3,4‐d]pyrimidine series. derivatives with 6‐aryl substituents
Authors: Southwick Philip L. , Madhav R. , Fitzgerald James A.
Published: May 2009

Methods are described for the synthesis of 6,7‐dihydro‐5H‐pyrrolo[3,4‐d]pyrimidines having an aryl substituent in the 6‐position. 4‐Hydroxy‐, 4‐amino, 2‐amino‐4‐hydroxy and 2,4‐diamino derivatives were obtained. The synthetic route involved the preparation of 1‐aryl‐4‐cyano‐ or 4‐carboalkoxy‐3‐pyrrolidinones and 1‐aryl‐4‐cyano‐ or 4‐carboalkoxy‐3‐amino‐3‐pyrrolines as key intermediates.
The NMR spectra of some substituted dibenzothiophenes
Authors: Campaigne E. , Ashby John
Published: May 2009

In order to use the NMR spectra of dibenzothiophenes to determine the position of substitution, a series of compounds has been prepared, most of which are new while some represent an improved method of preparation of previously reported compounds. With the exception of one, the structures of the compounds prepared were not in doubt, however the splitting patterns and chemical shifts presented here will facilitate future structure determinations of dibenzothiophenes.
The hydroxyacetylpiperidines and their N‐benzyl derivatives. The 2‐hydroxymethyl‐2‐piperidyl‐ and 2‐hydroxymethyl‐2‐pyridyl‐1,3‐dioxolanes
Authors: Nielsen Arnold T. , Platt Ernest N.
Published: May 2009

The hydroxyacetylpiperidines, their ethylene ketals, and the N‐benzyl derivatives of these new piperidines have been synthesized. Methylolation of 2‐(2‐ and 4‐pyridyl)‐1,3‐dioxolanes by heating with paraformaldehyde at 185° led to 2‐hydroxymethyl‐2‐(2‐ and 4‐pyridyl)‐i,3‐dioxolanes (7,8, respectively). 2‐Hydroxymethyl‐2‐(3‐pyridyl)‐1,3‐dioxolane (13) was obtained by reaction of 2‐bromomethyl‐2‐(3‐pyridyl)‐1,3‐dioxolane with aqueous sodium hydroxide at 190°. Hydrogenation of these pyridine ketals with rhodium‐charcoal catalyst produced the corresponding piperidine ketals (16,17,18). Acid hydrolysis of the piperidine ketals and their N‐benzyl derivatives led to the hydroxyacetylpiperidines (1,2,3) and their N‐benzyl derivatives (25,26,27). The N‐benzylhydroxyacetylpiperidines undergo rapid hydrogenolysis with palladium‐charcoal catalyst to produce the hydroxyacetylpiperidines. Further hydrogenation produces the piperidyl‐1,2‐ethanediols. The hydroxyacetylpiperidines are somewhat unstable, hygroscopic substances which polymerize with dehydration on standing; in solution they are relatively stable. Their N‐benzyl, ketal, and hydrochloride salt derivatives, on the other hand, represent stable, synthetically useful intermediates from which the reactive trifunctional hydroxyacetylpiperidines may readily be prepared.
Some reactions of 5‐methyl‐11H‐isoindolo[2,1‐α] benzimidazolium salts
Authors: Irick Gether
Published: May 2009

5‐Methyl‐11H‐isoindolo[2,1‐α]benzirnidazolium halide (IV), obtained by direct quaternization of the precursor III, underwent facile condensation reactions at its 11‐methylene group similar to those of 11H‐isoindolo[1,2‐b]benzothiazolium cation II. Although the treatment of II with alkali regenerated its precursor I, treatment of IV with alkali caused ring opening to a phthalimidine. Attempted thermal cyclization of 2‐(alkylaminophenyl)phthalimidines, e.g., VII, resulted in dealkylation to produce III.
Chemistry of thienopyridines. VIII. Substitution products derived from thieno[2,3‐b] pyridine 7‐oxide
Authors: Klemm L. H. , Barnish I. T. , Zell Reinhard
Published: May 2009

Thieno[2,3‐b]pyridine (I) was concerted to the N‐oxide (II, 53%) by means of hydrogen peroxide and acetic acid. Nitration of II in sulfuric acid gave 4‐nitrothieno[2,3‐b]pyridine 7‐oxide (III, 50%), while nitration in acetic acid formed the isomeric 5‐nitrothieno[2,3‐b]pyridine 7‐oxide (IV, 54%). Compounds III and IV were reduced to the corresponding 4‐ and 5‐aminothieno[2,3‐b]pyridines, respectively. Treatment of III with acetyl chloride gave 4‐chlorothieno‐[2,3‐b]pyridine 7‐oxide (XI, 81%), convertible in two steps to 4‐(N‐substituted amino)thieno‐[2,3‐b]pyridines (especially of the 4‐dialkylaminoalkylamino type) for screening as potential antimalarial drugs. 4‐Aminothieno[2,3‐b]pyridine reacted with aromatic aldehydes to give Schiff's bases and other products. Mechanisms for some of the reactions are suggested. NMR spectral data are reported for various 4‐substituted thieno[2,3‐b]pyridine compounds.
Chlorination of quinoline
Authors: Tong Y. C.
Published: May 2009

Chlorination of Quinoline at 160–190° without solvent gave a mixture of compounds. The five major components were isolated and identified as 3,4‐dichloro‐, 3,4,6‐, 3,4,8‐trichloro‐, 3,4,6,8‐tetrachloro‐ and 3,4,6,7,8‐pentachloroquinolines.
Synthesis of organic isocyanates. I. Thermal decomposition of substituted 1,3,2,4‐dioxathiazole S‐oxides
Authors: Burk Emmett H. , Carlos Donald D.
Published: May 2009

A new synthesis of aromatic isocyanates from hydroxamic acids is described which involves pyrolysis of the derived 1,3,2,4‐dioxathiazole S‐oxides.
De la synthèse du formyl‐2 hydroxy‐3 sélénophène et de l'acétyl‐2 hydroxy‐3 sélénophène
Authors: Morel J. , Paulmier C. , Pastour P.
Published: May 2009

Le formyl‐2 hydroxy‐3 sélénophène et l'acétyl‐2 hydroxy‐3 sélénophène ont été synthétises par désalkylation d'éthers tert‐butoxylés; pour ces deux composés l'importance des liaisons hydrogènes est mise en évidence.
Synthesis of some derivatives of imidazo[1,2‐a]pyridine, pyrazolo[1,5‐b]imidazole, and 4‐(3H)quinazolinone from α‐ketohydrazidoyl bromides
Authors: Shawali Ahmad S. , Sami M. , Sherif S. Mourad , Párkányi Cyril
Published: May 2009

α‐Aroyl‐N‐arylhydrazidoyl bromides 1 react with 2‐aminopyridine in ethanol and give 2‐aryl‐3‐arylazo‐imidazo[1,2‐α]pyridines 2 in 60‐75% yield. The reaction of 1 with 3‐phenyl‐5‐aminopyrazole in ethanol leads to 2,6‐diaryl‐3‐arylazo‐1H‐pyrazolo[1,5‐b]imidazoles 3 in almost quantitative yield. Also, 1 react with anthran‐ilic acid in the presence of triethylamine giving 3‐arylamino‐2‐aroyl‐4‐(3H)quinazolinones 4 in 80‐85% yield. The structures of the products were assigned and confirmed on the basis of their elemental analysis and electronic absorption, infrared and nmr spectra.
Pulse radiolysis study of the reduction of 1‐phenyl‐1‐cyanonitroethylene. Cyclization leading to 5‐amino‐4‐phenylisoxazole
Authors: Deswarte S. , Bellec C. , Pucheault J. , Ferradini C. , Gilles L.
Published: May 2009

It is known that the electrochemical reduction of the 1‐phenyl‐1‐cyanonitroethylene leads to the formation of a cyclic compound, the 5‐amino‐4‐phenyl isoxazole, but the mechanism of such a cyclization, which is pH dependent, is not clearly established. Pulse radiolytic methods were used to follow the various stages resulting from the reduction of the 1‐phenyl‐l‐cyanonitroethylene by the radical anion COO− in order to obtain a better understanding of the preceding reduction. The transient spectra are studied between 250 and 400 nm for times ranging from 4 microseconds to several minutes after the pulse; one of these spectra concerns the ene hydroxylamine. As expected, the changes and evolution of the spectra are pH dependent and corresponding mechanisms are proposed to explain the cyclization following the formation of the ene hydroxylamine. A general scheme is given taking into account all the results obtained.
Synthesis of 4,7,9‐trimethyl‐2H‐thieno[3,2‐g]‐1‐benzopyran‐2‐one. A psoralen isostere
Authors: Wellman George R.
Published: May 2009

The title compound, an isostere of 4,5′,8‐trimethylpsoralen, was prepared in good yield from 7‐[(2‐bromo‐allyl)thio]‐4,8‐dimethylcoumarin via a thio‐Claisen rearrangement. The structure of the final product was determined by proton nmr decoupling experiments.
Mass spectrometric fragmentation of saturated six membered heterocyclic systems containing two chalcogen family atoms
Authors: Kulkarni P. S. , Khan M. M. , Sturgeon G. D. , Gross M. L.
Published: May 2009

The mass spectra of six‐membered saturated heterocycles containing oxygen, sulphur, selenium and tellurium in the 1,4‐positions have been measured. The differing fragmentation modes have been characterized using high resolution, low voltage and metastable ion scan techniques. The important decomposition reactions of the molecular ions involve elimination of C2H4 and CH2X (X is a chalcogen atom) and formation of [C2H4X]+ and C2H5+. The propensities of these reactions vary systematically as a function of the ability of the chalcogen to stabilize a positive charge.
A new synthesis of methoxalen
Authors: Nore Pentti , Honkanen Erkki
Published: May 2009

A new seven step synthesis of methoxalen, 9‐methoxy‐7H‐furo[3,2‐g][1]benzopyran‐7‐one, starting from 2‐chloro‐2′‐hydroxy‐3′,4′‐dimethoxyacetophenone is described. The yields in every step are good (60‐100%).
Benzo[b]naphtho[2,1‐d]thiophene (thiachrysene) derivatives as potential carcinostatic molecules
Authors: Alunni‐Bistocchi Giovanni , De Meo Giovanni , Pedini Mauro , Ricci Adolfo , Jacquignon Pierre , Croisy Alain
Published: May 2009

About twenty compounds of the benzo[b]naphtho[2,1‐d]thiophene series have been synthesized, namely, 6‐amino derivatives, with the aim of biological testing as possible carcinostatic molecules.