bluuebunny/crossref_metadata_2025 huggingface dataset:
Tessellation Analysis of Glomerular Spatial Arrangement in Mice with Heritable Renal Hypoplasia
Authors: Wong Brittany , Farrell Michael L. , Yang Shiming , Freitas Tracey , Lozanoff Scott
Published: November 2009

Renal hypoplasia results from an insufficient kidney volume caused, in part, by a deficient number of glomeruli. The purpose of this study was to apply tessellation analysis to determine whether glomerular point patterns differed between adult normal (WT) and mutant (Br) mice with heritable renal hypoplasia and to delineate a spatial distribution accounting for the observed patterns. Kidneys from adult WT and Br mice were collected, processed with routine light histology and representative transverse sections were photographed. Cortical area and perimeter were calculated from traced tissue contours and glomeruli were identified and digitized. Voronoi tessellations were constructed and average parameters for Voronoi polygon number, area, perimeter and edge counts as well as spatial metrics comprising nearest neighbor and centroidal distances were calculated and compared. Point distributions were simulated by randomizing glomerular coordinates from each section and plotting the new points utilizing uniform random, Gaussian random, or isotropic functions. Average nearest neighbor distances were generated for each specimen and ranked with respect to corresponding values generated from 1,000 iterations for each simulated set. Results showed that WT and Br were significantly different for each parameter suggesting that WT kidneys possessed more glomeruli, but these were less clustered compared to Br. Simulations suggested that WT and Br demonstrated similar, but not identical, underlying glomerular spatial distributions. Defective gene expression in Br is important for determining glomerular number and the defective pattern likely results from a heterochronic disturbance consisting of a truncated growth trajectory during embryonic kidney development. Anat Rec, 2010. © 2009 Wiley‐Liss, Inc.
The Circumorbital Bones of the Gekkota (Reptilia: Squamata)
Authors: Daza Juan Diego , Bauer Aaron Matthew
Published: November 2009

The enormous variation of the orbit in lepidosaurs is better conceptualized in terms of composition and configuration. Broadly, the orbit varies from having totally closed rim to being open posteriorly. Two processes are responsible for changes in the components of the circumorbital series, element loss and fusion. The resulting contacts among elements are the main factors determining orbital configuration. Here, we present a revision of the gekkotan circumorbital bones in the general context of the Lepidosauria. From observations of a sample of 105 species of gekkotans prepared using different techniques, we describe the main changes in the orbit and corroborate the presence or absence of some of the ambiguous elements such as the lacrimal and the jugal. The supraorbital bones of squamates are reviewed and some problems of homology are evaluated using recent phylogenenetic hypothesis. Anat Rec, 2010. © 2009 Wiley‐Liss, Inc.
Testing reported associations of genetic risk factors for oral clefts in a large Irish study population
Authors: Carter Tonia C. , Molloy Anne M. , Pangilinan Faith , Troendle James F. , Kirke Peadar N. , Conley Mary R. , Orr David J. A. , Earley Michael , McKiernan Eamon , Lynn Ena C. , Doyle Anne , Scott John M. , Brody Lawrence C. , Mills James L.
Published: November 2009

BACKGROUND:

Suggestive, but not conclusive, studies implicate many genetic variants in oral cleft etiology. We used a large, ethnically homogenous study population to test whether reported associations between nonsyndromic oral clefts and 12 genes (CLPTM1, CRISPLD2, FGFR2, GABRB3, GLI2, IRF6, PTCH1, RARA, RYK, SATB2, SUMO1, TGFA) could be confirmed.

METHODS:

Thirty‐one single nucleotide polymorphisms (SNPs) in exons, splice sites, and conserved non‐coding regions were studied in 509 patients with cleft lip with or without cleft palate (CLP), 383 with cleft palate only (CP), 838 mothers and 719 fathers of patients with oral clefts, and 902 controls from Ireland. Case‐control and family‐based statistical tests were performed using isolated oral clefts for the main analyses.

RESULTS:

In case‐control comparisons, the minor allele of PTCH1 A562A (rs2066836) was associated with reduced odds of CLP (odds ratios [OR], 0.29; 95% confidence interval [CI], 0.13–0.64 for homozygotes), whereas the minor allele of PTCH1 L1315P (rs357564) was associated with increased odds of CLP (OR, 1.36; 95% CI, 1.07–1.74 for heterozygotes; and OR, 1.56; 95% CI, 1.09–2.24 for homozygotes). The minor allele of one SUMO1 SNP, rs3769817 located in intron 2, was associated with increased odds of CP (OR, 1.45; 95% CI, 1.06–1.99 for heterozygotes). Transmission disequilibrium was observed for the minor allele of TGFA V159V (rs2166975) which was over‐transmitted to CP cases (p = 0.041).

CONCLUSIONS:

For 10 of the 12 genes, this is the largest candidate gene study of nonsyndromic oral clefts to date. The findings provide further evidence that PTCH1, SUMO1, and TGFA contribute to nonsyndromic oral clefts. Birth Defects Research (Part A) 2010. © 2009 Wiley‐Liss, Inc.
Contrasting Effects of Axial Ligands on Electron‐Transfer Versus Proton‐Coupled Electron‐Transfer Reactions of Nonheme Oxoiron(IV) Complexes
Authors: Fukuzumi Shunichi , Kotani Hiroaki , Suenobu Tomoyoshi , Hong Seungwoo , Lee Yong‐Min , Nam Wonwoo
Published: November 2009

The effects of axial ligands on electron‐transfer and proton‐coupled electron‐transfer reactions of mononuclear nonheme oxoiron(IV) complexes were investigated by using [FeIV(O)(tmc)(X)]n+ (1‐X) with various axial ligands, in which tmc is 1,4,8,11‐tetramethyl‐1,4,8,11‐tetraazacyclotetradecane and X is CH3CN (1‐NCCH3), CF3COO− (1‐OOCCF3), or N3− (1‐N3), and ferrocene derivatives as electron donors. As the binding strength of the axial ligands increases, the one‐electron reduction potentials of 1‐X (Ered, V vs. saturated calomel electrode (SCE)) are more negatively shifted by the binding of the more electron‐donating axial ligands in the order of 1‐NCCH3 (0.39) > 1‐OOCCF3 (0.13) > 1‐N3 (−0.05 V). Rate constants of electron transfer from ferrocene derivatives to 1‐X were analyzed in light of the Marcus theory of electron transfer to determine reorganization energies (λ) of electron transfer. The λ values decrease in the order of 1‐NCCH3 (2.37) > 1‐OOCCF3 (2.12) > 1‐N3 (1.97 eV). Thus, the electron‐transfer reduction becomes less favorable thermodynamically but more favorable kinetically with increasing donor ability of the axial ligands. The net effect of the axial ligands is the deceleration of the electron‐transfer rate in the order of 1‐NCCH3 > 1‐OOCCF3 > 1‐N3. In sharp contrast to this, the rates of the proton‐coupled electron‐transfer reactions of 1‐X are markedly accelerated in the presence of an acid in the opposite order: 1‐NCCH3 < 1‐OOCCF3 < 1‐N3. Such contrasting effects of the axial ligands on the electron‐transfer and proton‐coupled electron‐transfer reactions of nonheme oxoiron(IV) complexes are discussed in light of the counterintuitive reactivity patterns observed in the oxo transfer and hydrogen‐atom abstraction reactions by nonheme oxoiron(IV) complexes (Sastri et al. Proc. Natl. Acad. Sci. U.S.A. 2007, 104, 19 181–19 186).
On the Mechanism of Urea‐Induced Titania Modification
Authors: Mitoraj Dariusz , Kisch Horst
Published: November 2009

The mechanism of surface modification of titania by calcination with urea at 400 °C was investigated by substituting urea by its thermal decomposition products. It was found that during the urea‐induced process titania acts as a thermal catalyst for the conversion of intermediate isocyanic acid to cyanamide. Trimerization of the latter produces melamine followed by polycondensation to melem‐ and melon‐based poly(aminotri‐s‐triazine) derivatives. Subsequently, amino groups of the latter finish the process by formation of TiN bonds through condensation with the OH‐terminated titania surface. When the density of these groups is too low, like in substoichiometric titania, no corresponding modification occurs. The mechanistic role of the polytriazine component depends on its concentration. If present in only a small amount, it acts as a molecular photosensitizer. At higher amounts it forms a crystalline semiconducting organic layer, chemically bound to titania. In this case the system represents a unique example of a covalently coupled inorganic–organic semiconductor photocatalyst. Both types of material exhibit the quasi‐Fermi level of electrons slightly anodically shifted relative to that of titania. They are all active in the visible‐light mineralization of formic acid, whereas nitrogen‐modified titania prepared from ammonia is inactive.
Gold‐Catalyzed Transannular [4+3] Cycloaddition Reactions
Authors: Gung Benjamin W. , Craft Derek T. , Bailey Lauren N. , Kirschbaum Kristin
Published: November 2009

Macrocyclic propargyl acetates containing a furan ring were prepared by using a CrCl2‐promoted reaction. In the presence of either a AuI or AuIII catalyst, a tandem 3,3‐rearrangement/transannular [4+3] cycloaddition reaction occurred to give propargyl acetates that are regio‐ and diastereospecific. The regiochemistry of the product is controlled by the position of the acetoxy group in the starting material and the stereochemistry of the reaction depends on the ring size.
Chiral and structural analysis of biomolecules using mass spectrometry and ion mobility‐mass spectrometry
Authors: Enders Jeffrey R. , Mclean John A.
Published: November 2009

This report describes the strategies for gas‐phase chiral and structural characterization of biomolecules using mass spectrometry (MS) and ion mobility‐MS (IM‐MS) techniques. Because both MS and IM‐MS do not directly provide chiral selectivity, methodologies for adding a chiral selector are discussed in the context of (i) host–guest (H–G) associations, (ii) diastereomeric collision‐induced dissociation (CID) methods, (iii) ion–molecule reactions, and (iv) the kinetic method. MS techniques for the analysis of proteins and protein complexes are briefly described. New advances in performing rapid 2D gas‐phase separations on the basis of IM‐MS are reviewed with a particular emphasis on the different forms of IM instrumentation and how they are used for chiral and/or structural biomolecular studies. This report is not intended to be a comprehensive review of the field, but rather to underscore the contemporary techniques that are commonly or increasingly being used to complement measurements performed by chiroptical methodologies. Chirality 21:E253–E264, 2009. © 2009 Wiley‐Liss, Inc.
Anticancer Therapeutics That Target Selenoenzymes: Synthesis, Characterization, in vitro Cytotoxicity, and Thioredoxin Reductase Inhibition of a Series of Gold(I) Complexes Containing Hydrophilic Phosphine Ligands
Authors: Vergara Elena , Casini Angela , Sorrentino Francesca , Zava Olivier , Cerrada Elena , Rigobello Maria Pia , Bindoli Alberto , Laguna Mariano , Dyson Paul J.
Published: November 2009

Gold(I) complexes bearing water‐soluble phosphine ligands, including 1,3,5‐triaza‐7‐phosphaadamantane (PTA), 3,7‐diacetyl‐1,3,7‐triaza‐5‐phosphabicyclo[3.3.1]nonane (DAPTA), and sodium triphenylphosphine trisulfonate (TPPTS), in combination with thionate ligands, were screened for their antiproliferative activities against human ovarian cancer cell lines A2780 either sensitive or resistant to cisplatin. In addition, the compounds were screened for their inhibition of mammalian thioredoxin reductases (TrxR), enzymes that are overexpressed in many tumor cells and contribute to drug resistance. The gold(I)–phosphine complexes efficiently inhibited cytosolic and mitochondrial TrxRs at concentrations that did not affect the related oxidoreductase glutathione reductase (GR). Additional complementary information on the enzyme metallation process and potential gold binding sites was obtained through the application of a specific biochemical assay using a thiol‐tagging reagent, BIAM (biotin‐conjugated iodoacetamide).
Major histocompatability complex class I expression and glial reaction influence spinal motoneuron synaptic plasticity during the course of experimental autoimmune encephalomyelitis
Authors: Freria C.M. , Zanon R.G. , Santos L.M.B. , Oliveira A.L.R.
Published: November 2009

Recent studies have shown that major histocompatibility complex class I (MHC I) expression directly influences the stability of nerve terminals. Also, the acute phase of experimental autoimmune encephalomyelitis (EAE) has shown a significant impact on inputs within the spinal cord. Therefore, the present work investigated the synaptic covering of motoneurons during the induction phase of disease and progressive remissions of EAE. EAE was induced in C57BL/6J mice, which were divided into four groups: normal, peak disease, first remission, and second remission. The animals were killed and their lumbar spinal cords processed for in situ hybridization (IH), immunohistochemistry, and transmission electron microscopy (TEM). The results indicated an increase in glial reaction during the peak disease. During this period, the TEM analysis showed a reduction in the synaptic covering of the motoneurons, corresponding to a reduction in synaptophysin immunolabeling and an increase in the MHC I expression. The IH analysis reinforced the immunolabeling results, revealing an increased expression of MHC I mRNA by motoneurons and nonneuronal cells during the peak disease and first remission. The results observed in both remission groups indicated a return of the terminals to make contact with the motoneuron surface. The ratio between excitatory and inhibitory inputs increased, indicating the potential for development of an excitotoxic process. In conclusion, the results presented here indicate that MHC I up‐regulation during the course of EAE correlates with the periods of synaptic plasticity induced by the infiltration of autoreactive immune cells and that synaptic plasticity decreases after recurrent peaks of inflammation. J. Comp. Neurol. 518:990–1007, 2010. © 2009 Wiley‐Liss, Inc.
Synaptic plasticity after chemical deafening and electrical stimulation of the auditory nerve in cats
Authors: Ryugo D.K. , Baker C.A. , Montey K.L. , Chang L.Y. , Coco A. , Fallon J.B. , Shepherd R.K.
Published: November 2009

The effects of deafness on brain structure and function have been studied using animal models of congenital deafness that include surgical ablation of the organ of Corti, acoustic trauma, ototoxic drugs, and hereditary deafness. This report describes the morphologic plasticity of auditory nerve synapses in response to ototoxic deafening and chronic electrical stimulation of the auditory nerve. Normal kittens were deafened by neonatal administration of neomycin that eliminated auditory receptor cells. Some of these cats were raised deaf, whereas others were chronically implanted with cochlear electrodes at 2 months of age and electrically stimulated for up to 12 months. The large endings of the auditory nerve, endbulbs of Held, were studied because they hold a key position in the timing pathway for sound localization, are readily identifiable, and exhibit deafness‐associated abnormalities. Compared with those of normal hearing cats, synapses of ototoxically deafened cats displayed expanded postsynaptic densities, a 35.4% decrease in synaptic vesicle (SV) density, and a reduction in the somatic size of spherical bushy cells (SBCs). In comparison with normal hearing cats, ototoxically deafened cats that received cochlear stimulation had endbulbs that expressed postsynaptic densities (PSDs) that were statistically identical in size, showed a 48.1% reduction in SV density, and whose target SBCs had a 25.5% reduction in soma area. These results demonstrate that electrical stimulation via a cochlear implant in chemically deafened cats preserves PSD size but not other aspects of synapse morphology. This determination further suggests that the effects of ototoxic deafness are not identical to those of hereditary deafness. J. Comp. Neurol. 518:1046–1063, 2010. © 2009 Wiley‐Liss, Inc.
Immunocytochemical localization of synaptic proteins to photoreceptor synapses of Drosophila melanogaster
Authors: Hamanaka Yoshitaka , Meinertzhagen Ian A.
Published: November 2009

The location of proteins that contribute to synaptic function has been widely studied in vertebrate synapses, far more than at model synapses of the genetically manipulable fruit fly, Drosophila melanogaster. Drosophila photoreceptor terminals have been extensively exploited to characterize the actions of synaptic genes, and their distinct and repetitive synaptic ultrastructure is anatomically well suited for such studies. Synaptic release sites include a bipartite T‐bar ribbon, comprising a platform surmounting a pedestal. So far, little is known about the composition and precise location of proteins at either the T‐bar ribbon or its associated synaptic organelles, knowledge of which is required to understand many details of synaptic function. We studied the localization of candidate proteins to pre‐ or postsynaptic organelles, by using immuno‐electron microscopy with the pre‐embedding method, after first validating immunolabeling by confocal microscopy. We used monoclonal antibodies against Bruchpilot, epidermal growth factor receptor pathway substrate clone 15 (EPS‐15), and cysteine string protein (CSP), all raised against a fly head homogenate, as well as sea urchin kinesin (antibody SUK4) and Discs large (DLG). All these antibodies labeled distinct synaptic structures in photoreceptor terminals in the first optic neuropil, the lamina, as did rabbit anti‐DPAK (Drosophila p21 activated kinase) and anti‐Dynamin. Validating reports from light microscopy, immunoreactivity to Bruchpilot localized to the edge of the platform, and immunoreactivity to SUK4 localized to the pedestal of the T‐bar ribbon. Anti‐DLG recognized the photoreceptor head of capitate projections, invaginating organelles from surrounding glia. For synaptic vesicles, immunoreactivity to EPS‐15 localized to sites of endocytosis, and anti‐CSP labeled vesicles lying close to the T‐bar ribbon. These results provide markers for synaptic sites, and a basis for further functional studies. J. Comp. Neurol. 518:1133–1155, 2010. © 2009 Wiley‐Liss, Inc.
Specializations of gastrin‐releasing peptide cells of the mouse suprachiasmatic nucleus
Authors: Drouyer Elise , LeSauter Joseph , Hernandez Amanda L. , Silver Rae
Published: November 2009

The suprachiasmatic nucleus (SCN) of the hypothalamus regulates daily rhythms in physiology and behavior. It is composed of a heterogeneous population of cells that together form the circuits underlying its master clock function. Numerous studies suggest the existence of two regions that have been termed core and shell. At a gross level, differences between these regions map to distinct functional differences, although the specific role(s) of various peptidergic cellular phenotypes remains unknown. In mouse, gastrin‐releasing peptide (GRP) cells lie in the core, are directly retinorecipient, and lack detectable rhythmicity in clock gene expression, raising interest in their role in the SCN. Here, we provide evidence that calbindin‐expressing cells of perinatal mouse SCN express GRP, identified by a green fluorescent protein (GFP+), but lack detectable calbindin later in development. To explore the intra‐SCN network in which GRP neurons participate, individual GFP+ cells were filled with tracer and their morphological characteristics, processes, and connections, as well as those of their non‐GFP‐containing immediate neighbors, were compared. The results show that GFP+ neurons form a dense network of local circuits within the core, revealed by appositions on other GFP+ cells and by the presence of dye‐coupled cells. Dendrites and axons of GFP+ cells make appositions on arginine vasopressin neurons, whereas non‐GFP cells have a less extensive fiber network, largely confined to the region of GFP+ cells. The results point to specialized circuitry within the SCN, presumably supporting synchronization of neural activity and reciprocal communication between core and shell regions. J. Comp. Neurol. 518:1249–1263, 2010. © 2009 Wiley‐Liss, Inc.
Regional distribution and cellular localization of β2‐adrenoceptors in the adult zebrafish brain (Danio rerio)
Authors: Ampatzis Konstantinos , Dermon Catherine R.
Published: November 2009

The β2‐adrenergic receptors (ARs) are G‐protein‐coupled receptors that mediate the physiological responses to adrenaline and noradrenaline. The present study aimed to determine the regional distribution of β2‐ARs in the adult zebrafish (Danio rerio) brain by means of in vitro autoradiographic and immunohistochemical methods. The immunohistochemical localization of β2‐ARs, in agreement with the quantitative β‐adrenoceptor autoradiography, showed a wide distribution of β2‐ARs in the adult zebrafish brain. The cerebellum and the dorsal zone of periventricular hypothalamus exhibited the highest density of [3H]CGP‐12177 binding sites and β2‐AR immunoreactivity. Neuronal cells strongly stained for β2‐ARs were found in the periventricular ventral telencephalic area, magnocellular and parvocellular superficial pretectal nuclei (PSm, PSp), occulomotor nucleus (NIII), locus coeruleus (LC), medial octavolateral nucleus (MON), magnocellular octaval nucleus (MaON) reticular formation (SRF, IMRF, IRF), and ganglionic cell layer of cerebellum. Interestingly, in most cases (NIII, LC, MON, MaON, SRF, IMRF, ganglionic cerebellar layer) β2‐ARs were colocalized with α2A‐ARs in the same neuron, suggesting their interaction for mediating the physiological functions of nor/adrenaline. Moderate to low labeling of β2‐ARs was found in neurons in dorsal telencephalic area, optic tectum (TeO), torus semicircularis (TS), and periventricular gray zone of optic tectum (PGZ). In addition to neuronal, glial expression of β2‐ARs was found in astrocytic fibers located in the central gray and dorsal rhombencephalic midline, in close relation to the ventricle. The autoradiographic and immunohistochemical distribution pattern of β2‐ARs in the adult zebrafish brain further support the conserved profile of adrenergic/noradrenergic system through vertebrate brain evolution. J. Comp. Neurol. 518:1418–1441, 2010. © 2009 Wiley‐Liss, Inc.
Density Functional Theory Calculations of 95Mo NMR Parameters in Solid‐State Compounds
Authors: Cuny Jérôme , Furet Eric , Gautier Régis , Le Pollès Laurent , Pickard Chris J. , d'Espinose de Lacaillerie Jean‐Baptiste
Published: November 2009

The application of periodic density functional theory‐based methods to the calculation of 95Mo electric field gradient (EFG) and chemical shift (CS) tensors in solid‐state molybdenum compounds is presented. Calculations of EFG tensors are performed using the projector augmented‐wave (PAW) method. Comparison of the results with those obtained using the augmented plane wave + local orbitals (APW+lo) method and with available experimental values shows the reliability of the approach for 95Mo EFG tensor calculation. CS tensors are calculated using the recently developed gauge‐including projector augmented‐wave (GIPAW) method. This work is the first application of the GIPAW method to a 4d transition‐metal nucleus. The effects of ultra‐soft pseudo‐potential parameters, exchange‐correlation functionals and structural parameters are precisely examined. Comparison with experimental results allows the validation of this computational formalism.
Light‐Induced Stored Information in Nanoparticles
Authors: Neville Suzanne M. , Etrillard Céline , Asthana Saket , Létard Jean‐François
Published: November 2009

We investigate here the consequence on light‐induced and thermally induced spin‐crossover (SCO) properties with particle size reduction from the macroscopic to microscale to nanoscale domains. Three samples with distinct particle sizes of the SCO coordination polymer [Fe(NCS)2(bpe)2] [bpe = 1,2‐bis(4′‐pyridyl)ethane] have been prepared by water‐in‐oil reverse micelle methods. Comparison of the magnetic properties with particle size reduction of these and the original macroscale slow‐grown crystals revealed that the spin transition becomes more gradual, more incomplete and concomitantly the transition temperature (T1/2) decreases – much like what is observed in metal dilution studies. Importantly, here, in the first photoinduced magnetic studies on a nanoparticle SCO system, we see that even on the nanoscale photoconversion of the low spin species to a metastable high‐spin state is possible. Furthermore, particle size reduction appears to have little effect on the temperature at which the stored photomagnetic information is erased. These results highlight that light‐induced SCO properties are governed by direct metal coordination environment (i.e., on the molecular scale), whereas, thermally induced magnetic properties rely more on crystal packing and ligand field effects.
Enantioselective Fujiwara–Moritani Indole and Pyrrole Annulations Catalyzed by Chiral Palladium(II)–NicOx Complexes
Authors: Schiffner Julia A. , Wöste Thorsten H. , Oestreich Martin
Published: November 2009

The catalytic asymmetric Fujiwara–Moritani ring closures of several indole‐ and pyrrole‐based cyclization precursors are reported. These unprecedented oxidative palladium(II)‐catalyzed annulations allow for the formation of a stereogenic quaternary carbon atom, and decent levels of enantiocontrol are seen in 5‐exo‐trig cyclizations (54 % ee for an indole and 76 % ee for a pyrrole) while 6‐exo‐trig ring closures afford essentially racemic material. Novel oxazoline ligands with a nicotine platform (NicOx) are pivotal for good catalytic turnover as conventional PyOx ligands failed to produce acceptable chemical yields. The preparation of these NicOx ligands as well as the syntheses of the cyclization precursors are described in detail.
An Asymmetric Tandem Conjugative Addition‐Intramolecular Cyclisation Process to Provide Functionalised 3,6‐Dihydropyrans and 4,5‐Epoxytetrahydropyrans
Authors: Catalán‐Muñoz Silvia , Müller Constanze A. , Ley Steven V.
Published: November 2009

The synthesis of 3,6‐dihydropyrans and 4,5‐epoxytetrahydropyrans starting from enantiomerically pure β‐hydroxy aldehyde (prepared by an organocatalytic aldol reaction) is described. The key step is a tandem sequence, which consists of a base‐promoted conjugative addition to a vinyl onium salt, followed by either an intramolecular Wittig process to provide 3,6‐dihydropyran derivatives or an intramolecular cyclisation/epoxidation process to afford 4,5‐epoxytetrahydropyran scaffolds. The products obtained by this method are common substructures in polyketide natural products.
Bridging the gap: health equality and the deficit framing of health
Authors: Morton Alec
Published: November 2009

The analyst tasked with measuring population health, with appraising healthcare investments, or allocating healthcare resources, may frame their task in one of two possible ways: either as being concerned with health assets (e.g. health expectancy or stock of QALYs), or with health deficits (a ‘health gap’, analogous to the poverty gap). In this paper, we discuss the consequences of taking the asset or the deficit concept as one's basic building block in developing a health measurement system when one has concerns about equitable distribution. We conclude that building metrics from a primitive health gap concept is possible and indeed may offer insights not otherwise easily accessible. Copyright © 2009 John Wiley & Sons, Ltd.
Effects of state‐level public spending on health on the mortality probability in India
Authors: Farahani Mansour , Subramanian S. V. , Canning David
Published: November 2009

This study uses the second National Family Health Survey of India to estimate the effect of state‐level public health spending on mortality across all age groups, controlling for individual, household, and state‐level covariates. We use a state's gross fiscal deficit as an instrument for its health spending. Our study shows a 10% increase in public spending on health in India decreases the average probability of death by about 2%, with effects mainly on the young, the elderly, and women. Other major factors affecting mortality are rural residence, household poverty, and access to toilet facilities. Copyright © 2009 John Wiley & Sons, Ltd.
A two‐stage estimation of hospital quality using mortality outcome measures: an application using hospital administrative data
Authors: Chua Chew Lian , Palangkaraya Alfons , Yong Jongsay
Published: November 2009

This paper proposes a method of deriving a quality indicator for hospitals using mortality outcome measures. The method aggregates any number of mortality outcomes into a single indicator via a two‐stage procedure. In the first stage, mortality outcomes are risk‐adjusted using a system of seemingly unrelated regression equations. These risk‐adjusted mortality rates are then aggregated into a single quality indicator in the second stage via weighted least squares. This method addresses the dimensionality problem in measuring hospital quality, which is multifaceted in nature. In addition, our method also facilitates further analyses of determinants of hospital quality by allowing the resulting quality estimates be associated with hospital characteristics. The method is applied to a sample of heart‐disease episodes extracted from hospital administrative data from the state of Victoria, Australia. Using the quality estimates, we show that teaching hospitals and large regional hospitals provide higher quality of care than other hospitals and this superior performance is related to hospital case‐load volume. Copyright © 2009 John Wiley & Sons, Ltd.
Marijuana use and high school dropout: the influence of unobservables
Authors: McCaffrey Daniel F. , Liccardo Pacula Rosalie , Han Bing , Ellickson Phyllis
Published: November 2009

In this study, we reconsider the relationship between heavy and persistent marijuana use and high school dropout status. Using a unique prospective panel study of over 4500 7th grade students from South Dakota who are followed through high school, we developed propensity score weights to adjust for baseline differences found to exist before marijuana initiation occurs for most students (7th grade). We then used weighted logistic regression that incorporates these propensity score weights to examine the extent to which time‐varying factors, including substance use, also influence the likelihood of dropping out of school. We found a positive association between marijuana use and dropping out (OR=5.6, RR=3.8), over half of which was explained by prior differences in observational characteristics and behaviors. The remaining association (OR=2.4, RR=1.7) became statistically insignificant when measures of cigarette smoking were included in the analysis. Because cigarette smoking is unlikely to seriously impair cognition, we interpret this result as evidence that the association between marijuana use and high school dropout is unlikely to be due to its adverse effects on cognition. We then explored which constructs drive this result, determining that they are time‐varying parental and peer influences. Copyright © 2009 John Wiley & Sons, Ltd.
Increased soluble serum markers caspase‐cleaved cytokeratin‐18, histones, and ST2 indicate apoptotic turnover and chronic immune response in COPD
Authors: Hacker Stefan , Lambers Christopher , Pollreisz Andreas , Hoetzenecker Konrad , Lichtenauer Michael , Mangold Andreas , Niederpold Tina , Hacker Andreas , Lang György , Dworschak Martin , Vukovich Thomas , Gerner Christopher , Klepetko Walter , Ankersmit Hendrik Jan
Published: November 2009

Introduction: Chronic obstructive pulmonary disease (COPD) is a worldwide burden and a major cause of death. The disease is accompanied by chronic inflammation and increased cellular turnover that is partly due to an overwhelming induction of apoptosis. In this study, we hypothesized that systemic markers of apoptosis are altered in patients with mild‐to‐severe COPD.

Materials and Methods: A total number of 64 patients and controls were enrolled in the study. Lung function parameters of all groups (nonsmoker, healthy smoker, COPD GOLD I&II, COPD GOLD III&IV) were evaluated at the time of inclusion. Enzyme‐linked immunosorbent assays were used to quantify protein levels in serum samples.

Results: Serum contents of apoptotic end‐products caspase‐cleaved cytokeratin‐18 and histone‐associated‐DNA‐fragments were increased in patients with COPD, whereas anti‐inflammatory soluble ST2 showed a peak in patients with COPD I&II (P=0.031) compared to healthy smokers. Levels of pro‐inflammatory caspase‐1/ ICE correlated significantly with the number of pack years (R=0.337; P=0.007).

Discussion: Our results indicate a systemic release of apoptosis‐specific proteins as markers for increased cellular turnover accompanied by progression of COPD. Furthermore, soluble ST2 seems to have a critical role in the anti‐inflammatory regulatory mechanism at early stages of the disease. J. Clin. Lab. Anal. 23:372–379, 2009. © 2009 Wiley‐Liss, Inc.
Gene diagnosis for nine Chinese patients with DMD/BMD by multiplex ligation‐dependent probe amplification and prenatal diagnosis for one of them
Authors: Wu Yupeng , Yin Gengxin , Fu Keqin , Wu De , Zhai Qian , Du Huarong , Huang Zhongjun , Niu Yuhua
Published: November 2009

This study aims to perform gene diagnosis for nine patients with Duchenne/Becker muscular dystrophy (DMD/BMD) and their parents with multiplex ligation‐dependent probe amplification (MLPA), and to carry out prenatal gene diagnosis for one of them. Genomic DNA of the peripheral blood and fetal amniotic fluid cell was extracted from the pedigrees' members with DMD/BMD. Gene diagnosis was performed for theses pedigrees' members using a SALSA KIT. Short tandem repeats (STR) genotyping and X‐linkage analysis were performed for the pedigree members of the fetus, which was used in the prenatal diagnosis. MLPA analysis results show that five of nine patients (DMD‐1, DMD‐2, DMD‐4, DMD‐8, and DMD‐9) with DMD/BMD were found to have several hemizygous exon deletions in the dystrophin gene. The other patients and the fetus did not have any hemizygous deletion or duplication of any exons. The genomic DNA of the fetus was not contaminated by his mother's DNA as identified by STR genotyping. In addition, X‐linkage analysis results show that the only X chromosome of the fetus comes from one of his mother's normal X chromosomes. Combined with STR genotyping and X‐linkage analysis, MLPA is a convenient, highly effective and reliable gene diagnosis technique for congenital genetic disease. J. Clin. Lab. Anal. 23:380–386, 2009. © 2009 Wiley‐Liss, Inc.
Prevalence characterization of extended‐spectrum β‐lactamases among Escherichia coli isolates collected in Zhengzhou
Authors: Zhang Zhijian , Guo Xiaobing , Zhang Qinxian
Published: November 2009

Objectives: To determine the prevalence and the diversity of extended‐spectrum β‐lactamases (ESBLs) among Escherichia coli isolates in Zhengzhou, China.

Methods: Clinical isolates were collected and investigated from the first affiliated hospital of Zhengzhou University and its associated health‐care facilities in Zhengzhou, China, during the period from January 2006 to June 2008. Antibiograms were performed on Mueller–Hinton agar plates with the disc‐diffusion method and MICs were determined by the agar‐dilution method. Total DNA was extracted with a Qiagen mini kit and screened by PCR.

Results: Of 94 nonduplicate ESBL‐positive isolates, TEM‐type was encoded in 74 and 79% of the ESBL isolates. Fifty‐six isolates were SHV type ESBLs. CTX‐M‐1, CTX‐M‐14, CTX‐M‐25, and CTX‐M‐38 types were encoded in 30, 54, 6, and 4, respectively. OXA‐1‐type β‐lactamases were encoded in six and OXA‐20‐type was encoded in two isolates.

Conclusions: We describe a complex ESBL epidemiology. The study revealed a high rate of ESBL‐producing E. coli isolates. TEM and CTX‐M enzymes dominated in ESBL‐positive E. coli isolates in Zhengzhou, China. J. Clin. Lab. Anal. 23:404–407, 2009. © 2009 Wiley‐Liss, Inc.
Spatio‐temporal patterns of pressure over the North Atlantic
Authors: Antunes Sílvia , Pires Oliveira , Rocha Alfredo
Published: November 2009

The North Atlantic mean sea level pressure field variability is analysed. A space–time study is performed using multichannel singular spectral analysis, allowing the detection of significant space–time modes of variability with periodicity behaviour. It is shown that there is a space variability associated with the time variability of the pressure field. The oscillation is not quasi‐meridional but has different orientations, rotating in a cycle, with a periodicity of about 9 years, from the positive North Atlantic oscillation (NAO) phase through the negative NAO phase and again to the positive phase. This periodicity behaviour was previously detected in the temporal principal components extracted from a principal component analysis but, in the time domain, it was found as not significant. Furthermore, the analysis of a long series of an NAO index had already revealed similar periodicity behaviour. Copyright © 2009 Royal Meteorological Society
Influence of Nanoparticles on the Rheological Behaviour and Initial Stages of Crystal Growth in Linear Polyethylene
Authors: Patil Nilesh , Balzano Luigi , Portale Giuseppe , Rastogi Sanjay
Published: November 2009

We demonstrate the role of broad molecular weight distribution (MWD) polyethylene (PE), in the presence of nanoparticles of different aspect ratios and binding efficiency with the polymer, in the formation of shish‐kebab structures under a shear protocol using time‐resolved small‐angle X‐ray scattering (SAXS). The results indicate a scattered intensity in the form of streaks at the equator while maxima in the meridian confirm the presence of an oriented structure in the polymer. The SAXS facilitated the probing of the steady growth of the obtained shish‐kebab structures at an isothermal crystallization temperature (136 °C). The study reveals the influence of nanoparticles (single walled carbon nanotubes (SWNTs) and zirconia) in chain orientation. The presence of nanoparticles promotes the high degree of orientation, where shish is formed along the flow direction and kebab perpendicular to it. A higher degree of chain orientation is observed in the presence of SWNTs compared to zirconia nanoparticles. The SWNTs present in a small concentration (< 0.6 wt.‐%) are aligned in the flow direction, which leads to an increase in shish length as estimated from Ruland's streak analysis. The stable shishes in the early stages of crystallization suppress the nucleation barrier for further crystallization. Compared to the polymer without nanoparticles the shish length increases in the presence of zirconia, however, the increase in shish length is much more pronounced in the presence of SWNTs compared to zirconia nanoparticles. The nanoparticles favor the orientation fraction as deduced from the integrated intensity of scattering at the equator and meridian in the patterns. Absence of a plateau in the low frequency region of the polymer–SWNT composites suggests the non‐existence of network formation. Nevertheless, comparing the storage modulus at two different temperatures (142 and 160 °C), suggests a strong temperature dependence and difference in adsorption energy of the two nanoparticles.

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Synthesis and Characterization of Soluble Poly(p‐phenylene) Derivatives for PLED Applications
Authors: Saikia Gunin , Singh Ranbir , Sarmah Pranjol Jyoti , Akhtar Mohammad Waseem , Sinha Jasmine , Katiyar Monica , Iyer Parameswar Krishnan
Published: November 2009

PPP derivatives with high molecular weights were synthesized and characterized by FT‐IR, 1H, 13C NMR and GPC. The decomposition temperatures of 2a–2c were above 300–400 °C. DSC analysis indicated their nature to be crystalline as all of them exhibited a melt temperature on controlled heating. Optical and electrochemical band gaps was determined using UV/Vis spectroscopy and CV. Single‐layer PLEDs fabricated with 2a–2c displayed high threshold voltages due to high potential barrier for holes. Their EL spectra reveal a small shift in blue peak and the emission form higher wavelength shoulder peak is enhanced.

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Recent Developments Concerning the Dispersion of Carbon Nanotubes in Polymers
Authors: Grady Brian P.
Published: November 2009

The ability to control the dispersion of carbon nanotubes in polymers is key to most applications of nanotube‐polymer composites. This feature article describes recent advances in methods used to disperse carbon nanotubes and considers how these methods affect dispersion on different length scales. It is becoming increasing clear that perfect dispersion is not desired for many applications, in particular for electrical conductivity, and controlling the dispersion is key for proper function of the composite in its intended application.

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A Study of Particle‐Surface Interactions During Olefin Polymerisation in Gas Phase Reactors
Authors: Eriksson Erik J. G. , McKenna Timothy F. L.
Published: November 2009

This work focuses on the heat exchange between a polymer particle and the reactor wall, especially for cases with low gas velocity. The role of different wall materials (or heat transfer conditions) is investigated with an eye to understanding how this influences the likelihood of particle melting, and, indirectly, wall sheeting. The main focus of this work was to simulate the temperature profiles inside growing polymer particles in the vicinity of the reactor wall when it is clean (steel) or covered with a layer of non reactive polymer. As a comparison, we have also simulated the reactor wall as being glass to represent bench scale polymerization equipment. The results from this work can help to understand how for instance wall sheeting can be accelerated if the reactor walls are not clean and how we can compare results from bench scale experiments to industrial scale units.
Modern Analytical Tools essential for Studying Olefin Polymerization
Authors: Hoffmann Michael S. , Nenov Svetlin , Diesing Till , Naundorf Corinna , Fink Gerhard , Klapper Markus , Müllen Klaus
Published: November 2009

As an alternative to inorganic supports, emulsions and organic carriers were developed for metallocene‐catalyzed polyolefin synthesis in the last years. Oil‐in‐oil emulsions based on a perfluorinated solvent provide the possibility to synthesize polymer particles on the nanometer length scale, while the latex particles consisting of polystyrene with different surface functionalities yield particles on the micrometer range. To obtain a deeper insight to the reaction course of both techniques and to the product morphology and fragmentation behavior of the organic carriers, substantial information concerning the kinetics of these reactions is crucial. Thus, standard analytical methods were combined with real‐time video microscopy and laser scanning fluorescence microscopy (LSCFM) of perylene labeled particles for improving these methods for polyolefin synthesis.
Heat Transfer in Gas Phase Olefin Polymerisation
Authors: Tioni Estevan , Broyer Jean Pierre , Spitz Roger , Monteil Vincent , McKenna Timothy F. L.
Published: November 2009

A fixed bed microreactor has been used to study heat transfer during the initial transient state of gas phase olefin polymerization on a supported catalyst. It has been shown that heat transfer during this stage of the polymerisation is critical, and under conditions found commercially problems can arise with hot spots and polymer melting. It is proven how the thermal properties of the gas mixture flowing on the catalytic bed exert great influence on heat dissipation reducing the sudden increase in temperature by as much as a factor of 5. Flow rate and especially the process gas composition are the key factors in controlling the bed temperature.
CRYSTAF Analysis of Polyethylene Synthesized with Phillips Catalyst
Authors: Xia Wei , Taniike Toshiaki , Terano Minoru , Fujitani Tadahiro , Liu Boping , Soares João B. P.
Published: November 2009

Crystallization analysis fractionation (CRYSTAF) was used for the first time to investigate the solution crystallization behavior of ethylene homopolymers and copolymers made with Phillips CrOx/SiO2 catalyst. Interestingly, the crystallization peak temperatures (Tp) of copolymers of ethylene and cyclopentene increased with increasing cyclopentene molar fraction in the copolymer. Comparing two factors (short chain branches (SCBs) and cyclopentene incorporation), decreasing SCB frequency is proposed as the dominant factor to explain the increase of crystallization peak temperatures with increasing cyclopentene incorporation. In addition, SCB frequency and molecular weight might be the two significant factors determining the crystallization temperature of polyethylene made with Phillips CrOx/SiO2 catalyst with different cocatalysts (triethylaluminum and diethylaluminum ethoxide).
Influence of Metallocene Type on the Order of Ethylene Polymerization and Catalyst Deactivation Rate in a Solution Reactor
Authors: Mehdiabadi Saeid , Soares João B.P.
Published: November 2009

The solution polymerization of ethylene using rac‐Et(Ind)2ZrCl2/MAO and (Dimethylsilyl(tert‐butylamido)(tetramethyl‐ cyclopentadienyl)titanium Dichloride)(CGC‐Ti)/MAO was studied in a semi‐batch reactor at 120 °C under different monomer pressures and catalyst concentrations. The kinetics of ethylene polymerization with rac‐Et(Ind)2ZrCl2/MAO can be described with first order reactions for polymerization and catalyst deactivation. When (CGC‐Ti)/MAO is used, however, second order kinetics are observed for catalyst decay and the order of polymerization changes from 2 to 1 with increasing ethylene pressure.
15N and 13C NMR chemical shifts of 6‐(fluoro, chloro, bromo, and iodo)purine 2′‐deoxynucleosides: measurements and calculations
Authors: Bai Shi , Dmitrenko Olga , Dybowski Cecil
Published: November 2009

The 15N and 13C chemical shifts of 6‐(fluoro, chloro, bromo, and iodo)purine 2′‐deoxynucleoside derivatives in deuterated chloroform were measured. The 15N chemical shifts were determined by the 1H15N HMBC method, and complete 15N chemical‐shift assignments were made with the aid of density functional theory (DFT) calculations. Inclusion of solvation effects significantly improved the precision of the calculations of 15N chemical shifts. Halogen‐substitution effects on the 15N and 13C chemical shifts of purine rings are discussed in the context of DFT results. The experimental coupling constants for 19F interacting with 15N and 13C of the 6‐fluoropurine 2‐deoxynuleoside are compared with those from DFT calculations. Copyright © 2009 John Wiley & Sons, Ltd.
Structural determination of aspericins AC, new furan and pyran derivates from the marine‐derived fungus Rhizopus sp. 2‐PDA‐61, by 1D and 2D NMR spectroscopy
Authors: Wang Fazuo , Zhu Tianjiao , Zhang Min , Lin Aiqun , Zhu Weiming , Gu Qianqun
Published: November 2009

Three new furan and pyran derivatives named aspericins AC (1–3), as well as a known asperic acid (4), have been isolated from the marine‐derived fungus Rhizopus sp. 2‐PDA‐61. The complete 1H and 13C NMR assignments for the new compounds were carried out using 1H, 13C, DEPT, COSY, HMQC, HMBC, and NOESY NMR experiments. Compounds 1–3 were evaluated for their cytotoxic activities on P388, A549, HL‐60, and BEL‐7420 cell lines by the MTT and SRB methods. Copyright © 2009 John Wiley & Sons, Ltd.