bluuebunny/crossref_metadata_2025 huggingface dataset:
Selective effect of age, Apo e4, and Alzheimer's disease on hippocampal subfields
Authors: Mueller Susanne G. , Weiner Michael W.
Published: April 2009

Histopathological studies and animal models suggest that different physiological and pathophysiological processes exert different subfield specific effects on the hippocampus. High‐resolution images at 4T depict details of the internal structure of the hippocampus allowing for in vivo volumetry of hippocampal subfields. The aims of this study were (1) to determine patterns of hippocampal subfield volume loss due to normal aging and Apo e4 carrier state, (2) to determine subfield specific volume losses due to preclinical (MCI) and clinical Alzheimer's disease (AD) and their modification due to age and Apo e4 carrier state. One hundred fifty seven subjects (119 cognitively healthy elderly controls, 20 MCI and 18 AD) were studied with a high resolution T2 weighted imaging sequence obtained at 4T aimed at the hippocampus. Apo e4 carrier state was known in 95 subjects (66 controls, 14 MCI, 15 AD). Subiculum (SUB), CA1, CA1‐CA2 transition zone (CA1‐2 transition), CA3‐ dentate gyrus (CA3&DG) were manually marked. Multiple linear regression analysis was used to test for effects of age, Apo e4 carrier state and effects of MCI and AD on different hippocampal subfields. Age had a significant negative effect on CA1 and CA3&DG volumes in controls (P < 0.05). AD had significantly smaller volumes of SUB, CA1, CA1‐2 transition, and MCI had smaller CA1‐2 transition volumes than controls (P < 0.05). Apo e4 carrier state was associated with volume loss in CA3&DG compared to non‐Apo e4 carriers in healthy controls and AD. Based on these findings, we conclude that subfield volumetry provides regional selective information that allows to distinguish between different normal and pathological processes affecting the hippocampus and thus for an improved differential diagnosis of neurodegenerative diseases affecting the hippocampus. © 2009 Wiley‐Liss, Inc.
Automated segmentation of hippocampal subfields from ultra‐high resolution in vivo MRI
Authors: Van Leemput Koen , Bakkour Akram , Benner Thomas , Wiggins Graham , Wald Lawrence L. , Augustinack Jean , Dickerson Bradford C. , Golland Polina , Fischl Bruce
Published: April 2009

Recent developments in MRI data acquisition technology are starting to yield images that show anatomical features of the hippocampal formation at an unprecedented level of detail, providing the basis for hippocampal subfield measurement. However, a fundamental bottleneck in MRI studies of the hippocampus at the subfield level is that they currently depend on manual segmentation, a laborious process that severely limits the amount of data that can be analyzed. In this article, we present a computational method for segmenting the hippocampal subfields in ultra‐high resolution MRI data in a fully automated fashion. Using Bayesian inference, we use a statistical model of image formation around the hippocampal area to obtain automated segmentations. We validate the proposed technique by comparing its segmentations to corresponding manual delineations in ultra‐high resolution MRI scans of 10 individuals, and show that automated volume measurements of the larger subfields correlate well with manual volume estimates. Unlike manual segmentations, our automated technique is fully reproducible, and fast enough to enable routine analysis of the hippocampal subfields in large imaging studies. © 2009 Wiley‐Liss, Inc.
Prolonged voluntary wheel‐running stimulates neural precursors in the hippocampus and forebrain of adult CD1 mice
Authors: Bednarczyk Matthew R. , Aumont Anne , Décary Simon , Bergeron Raynald , Fernandes Karl J.L.
Published: April 2009

Voluntary wheel‐running induces a rapid increase in proliferation and neurogenesis by neural precursors present in the adult rodent hippocampus. In contrast, the responses of hippocampal and other central nervous system neural precursors following longer periods of voluntary physical activity are unclear and are an issue of potential relevance to physical rehabilitation programs. We investigated the effects of a prolonged, 6‐week voluntary wheel‐running paradigm on neural precursors of the CD1 mouse hippocampus and forebrain. Examination of the hippocampus following 6 weeks of running revealed two to three times as many newly born neurons and 60% more proliferating cells when compared with standard‐housed control mice. Among running mice, the number of newly born neurons correlated with the total running distance. To establish the effects of wheel‐running on hippocampal precursors dividing during later stages of the prolonged running regime, BrdU was administered after 3 weeks of running and the BrdU‐retaining cells were analyzed 18 days later. Quantifications revealed that the effects of wheel‐running were maintained in late‐stage proliferating cells, as running mice had two to three times as many BrdU‐retaining cells within the hippocampal dentate gyrus, and these yielded greater proportions of both mature neurons and proliferative cells. The effects of prolonged wheel‐running were also detected beyond the hippocampus. Unlike short‐term wheel‐running, prolonged wheel‐running was associated with higher numbers of proliferating cells within the ventral forebrain subventricular region, a site of age‐associated decreases in neural precursor proliferation and neurogenesis. Collectively, these findings indicate that (i) prolonged voluntary wheel‐running maintains an increased level of hippocampal neurogenesis whose magnitude is linked to total running performance, and (ii) that it influences multiple neural precursor populations of the adult mouse brain. © 2009 Wiley‐Liss, Inc.
Improving the term structure of interest rates: two‐factor models
Authors: Gómez‐Valle Lourdes , Martínez‐Rodríguez Julia
Published: April 2009

We consider a new approach for estimating the coefficients of the term structure equation in two‐factor models. This approach is based on the fact that the risk‐neutral drifts of the factors are directly estimated. Therefore, the market prices of risk and the physical drifts do not have to be either identified or estimated.

In order to study the finite properties of this approach, we generate trajectories in a stochastic volatility model. We find that the risk‐neutral drifts and the yield curves are more accurately estimated. Finally, we show the supremacy of this approach by means of US Treasury Bill data. Copyright © 2009 John Wiley & Sons, Ltd.
Costs associated with mutual funds in Spain
Authors: Toledo Isabel , Marco Rocío
Published: April 2009

This study examines the mutual fund market in Spain from the point of view of management and custodial costs. For this purpose it estimates functions explaining these fees using ordinary least squares and panel data. The results confirm that the most relevant factors in determining the management fee are the risk incurred by the managed portfolio, the level of its cash holding, and the number of shareholders in relation to the size of the fund. In addition, it highlights two aspects of the Spanish market with respect to the results obtained by similar studies in the North American market and in some European countries (Finland, Italy): first, the lack of a learning curve reducing operational costs, and, second, the lack of economies of scale in the management costs. Copyright © 2009 John Wiley & Sons, Ltd.
Probing for local activity‐related modulation of the infrared backscattering of the brain cortex
Authors: Biella Gabriele E. M. , Trevisan Stefano , Giardini Mario E.
Published: April 2009

The possibility to measure the metabolic activity of the brain cortex, with submillimeter spatial and subsecond temporal resolution, would open up enticing scenarios in addressing basic issues on the relation between different structural components of brain signal processing, and in providing an operational pathway to interaction with (dis)functional signal patterns. In the present article, we report the description of a simple system that allows the detection of the minute changes that occur in the optical backscattering of the cortex as a metabolic response to external stimuli. The simplicity of the system is compatible with scalability to an implantable probe. We validate the system on an animal model, and we propose an algorithm to extract meaningful data from the measured signal. We thus show the detection of individual haemodynamic cortical responses to individual stimulation events, and we provide operational considerations on the signal structure. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Hematological responses of the grey carpet shark (Chiloscyllium punctatum) and the epaulette shark (Hemiscyllium ocellatum) to anoxia and re‐oxygenation
Authors: Chapman Clint A. , Renshaw Gillian M.C.
Published: April 2009

We compared the hematological responses of wild and captive populations of two closely related sharks to a standardized anoxic challenge and during a 12 hr recovery period in normoxia: the epaulette shark (Hemiscyllium ocellatum, Bonnaterre, 1788) and the grey carpet shark (Chiloscyllium punctatum, Müller and Henle, 1838). Compared to normoxic controls, a significant increase in hematocrit (captive 22.3%; wild 35.9%) coupled with a decline in mean corpuscular hemoglobin concentration occurred in epaulette sharks indicating erythrocyte swelling in response to anoxia. However, the grey carpet shark had a significantly increased hematocrit (captive 27.2%; wild 29.3%), erythrocyte count (captive 37.6%; wild 46.3%) and hemoglobin concentration (captive 31.9%; wild 31.5%), suggesting a release of erythrocytes into the circulation and/or hemoconcentration in response to anoxia. Plasma glucose concentrations were maintained in both wild and captive epaulette sharks and in wild grey carpet sharks during anoxia but increased significantly after 2 hr of re‐oxygenation (epaulette: captive 55.8%; wild 50.1%; grey carpet shark: wild 70.3%) and remained elevated for 12 hr. Captive grey carpet sharks had an immediate increase in plasma glucose concentrations after anoxia (96.4%), which was sustained for 12 hr of re‐oxygenation. Lactate concentrations significantly increased in captive and wild animals of both species after anoxia, reaching a peak at 2 hr of re‐oxygenation. Both species showed significant, yet divergent, hematological changes in response to anoxia and re‐oxygenation, which may not only prolong their survival and assist in recovery but also reflect their respective ecophysiological adaptations to the extreme environments that they inhabit. J. Exp. Zool. 311A:422–438, 2009. © 2009 Wiley‐Liss, Inc.
ZOONET: perspectives on the evolution of animal form. Meeting report
Authors: Fischer Antje H. L. , Arboleda Enrique , Egger Bernhard , Hilbrant Maarten , McGregor Alistair P. , Cole Alison G. , Daley Allison C.
Published: April 2009

What drives evolution? This was one of the main questions raised at the final ZOONET meeting in Budapest, Hungary, in November 2008. The meeting marked the conclusion of ZOONET, an EU‐funded Marie‐Curie Research Training Network comprising nine research groups from all over Europe (Max Telford, University College London; Michael Akam, University of Cambridge; Detlev Arendt, EMBL Heidelberg; Maria Ina Arnone, Stazione Zoologica Anton Dohrn Napoli; Michalis Averof, IMBB Heraklion; Graham Budd, Uppsala University; Richard Copley, University of Oxford; Wim Damen, University of Cologne; Ernst Wimmer, University of Göttingen). ZOONET meetings and practical courses held during the past four years provided researchers from diverse backgrounds—bioinformatics, phylogenetics, embryology, palaeontology, and developmental and molecular biology—the opportunity to discuss their work under a common umbrella of evolutionary developmental biology (Evo Devo). The Budapest meeting emphasized in‐depth discussions of the key concepts defining Evo Devo, and bringing together ZOONET researchers with external speakers who were invited to present their views on the evolution of animal form. The discussion sessions addressed four main topics: the driving forces of evolution, segmentation, fossils and phylogeny, and the future of Evo Devo. J. Exp. Zool. (Mol. Dev. Evol.) 312B:679–685, 2009. © 2009 Wiley‐Liss, Inc.
Cycle‐minors and subdivisions of wheels
Authors: Turner Galen E.
Published: April 2009

In this paper we prove two results. The first is an extension of a result of Dirac which says that any set of n vertices of an n‐connected graph lies in a cycle. We prove that if V′ is a set of at most 2n vertices in an n‐connected graph G, then G has, as a minor, a cycle using all of the vertices of V′. The second result says that if G is an n+1‐connected graph with maximum vertex degree Δ then G contains a subgraph that is a subdivision of W2n if and only if Δ≥2n. © 2009 Wiley Periodicals, Inc. J Graph Theory 62: 100–108, 2009
Constructing isospectral non‐isomorphic digraphs from hypergraphs
Authors: Balof Barry , Storm Christopher
Published: April 2009

We explore the “oriented line graph” construction associated with a hypergraph, leading to a construction of pairs of strongly connected directed graphs whose adjacency operators have the same spectra. We give conditions on a hypergraph so that a hypergraph and its dual give rise to isospectral, but non‐isomorphic, directed graphs. The proof of isospectrality comes from an argument centered around hypergraph zeta functions as defined by Storm. To prove non‐isomorphism, we establish a Whitney‐type result by showing that the oriented line graphs are isomorphic if and only if the hypergraphs are. © 2009 Wiley Periodicals, Inc. J Graph Theory 63: 231–242, 2010
Pyrimidines. XV. (Amino Acids. II.) DL‐β‐(dihydroxypyrimidinyl) alanines
Authors: Springer Roberr H. , Haggerty William J. , Cheng C. C.
Published: April 2009

The Prepration of two uracil derivatives of alanine, DL‐β‐(5‐uracilyl)alanine and DL‐β(6‐uracilyl)alanine, are reported. A structural analog, dl‐4,6‐dihydroxy‐β‐(2‐(pyrimidinyl)alanine, which was reported to be labile to acid hydrolysis, has now been successfully prepared in our laboratories.

The relationship between the relative position of an alanine moity on some nitrogen hetrocyclic ring systems and their color formation with ninhydrin are discussed.
Mitochondrial inhibitor 3‐nitroproprionic acid enhances oxidative modification of alpha‐synuclein in a transgenic mouse model of multiple system atrophy
Authors: Ubhi Kiren , Lee Phil Hyu , Adame Anthony , Inglis Chandra , Mante Michael , Rockenstein Edward , Stefanova Nadia , Wenning Gregor K. , Masliah Eliezer
Published: April 2009

Multiple system atrophy (MSA) is a progressive neurodegenerative disease characterized by autonomic failure, parkinsonism, cerebellar ataxia, and oligodendrocytic accumulation of alpha‐synuclein (αsyn). Oxidative stress has been linked to neuronal death in MSA and the mitochondrial toxin 3‐nitropropionic acid (3NP) is known to enhance the motor deficits and neurodegeneration in transgenic mice models of MSA. However, the effect of 3NP administration on αsyn itself has not been studied. In this context, we examined the neuropathological effects of 3NP administration in αsyn transgenic mice expressing human αsyn (hαsyn) under the control of the myelin basic protein (MBP) promoter and the effect of this administration on posttranslational modifications of αsyn, on levels of total αsyn, and on its solubility. We demonstrate that 3NP administration altered levels of nitrated and oxidized αsyn in the MBP‐hαsyn tg while not affecting global levels of phosphorylated or total αsyn. 3NP administration also exaggerated neurological deficits in the MBP‐hαsyn tg mice, resulting in widespread neuronal degeneration and behavioral impairment. © 2009 Wiley‐Liss, Inc.
Stereological investigation of age‐related changes of myelinated fibers in the rat cortex
Authors: Zhang Wei , Yang Shu , Li Chen , Chen Lin , Tang Yong
Published: April 2009

In the present study, the cortex volume, total volume, total length and mean diameter of the myelinated fibers in the cortices of young, middle‐aged, and aged Long‐Evans rats were quantitatively investigated by using stereological methods and electron microscopy techniques. There were no significant differences in the myelinated fibers between young and middle‐aged rat cortex. The cortex volume and the total length of the myelinated fibers in the cortex of aged rats were significantly lower than those of young and middle‐aged rats. However, no significant difference was found in the total volume of the myelinated fibers among three groups. The disproportional changes in the total length and total volume of the myelinated fibers in the cortex of aged rats and the absolute distribution of the total length of the myelinated fibers in the cortex of the three groups suggested that the age‐induced decrease of the myelinated fibers might be due mainly to a loss of the myelinated fibers with smaller diameters. The present results together with our previous findings indicated that the age‐related changes of the myelinated fibers occurred widely in the central nervous system and that the age‐related changes of the myelinated fibers in cortex occurred later than those in white matter. © 2009 Wiley‐Liss, Inc.
Acetylcholine synthesis and release in NIH3T3 cells coexpressing the high‐affinity choline transporter and choline acetyltransferase
Authors: Fujii Takeshi , Masai Manabu , Misawa Hidemi , Okuda Takashi , Takada‐Takatori Yuki , Moriwaki Yasuhiro , Haga Tatsuya , Kawashima Koichiro
Published: April 2009

Acetylcholine (ACh) is known to be a key neurotransmitter in the central and peripheral nervous systems, but it is also produced in a variety of non‐neuronal tissues and cells, including lymphocytes, placenta, amniotic membrane, vascular endothelial cells, keratinocytes, and epithelial cells in the digestive and respiratory tracts. To investigate contribution made by the high‐affinity choline transporter (CHT1) to ACh synthesis in both cholinergic neurons and nonneuronal cells, we transfected rat CHT1 cDNA into NIH3T3ChAT cells, a mouse fibroblast line expressing mouse choline acetyltransferase (ChAT), to establish the NIH3T3ChAT 112‐1 cell line, which stably expresses both CHT1 and ChAT. NIH3T3ChAT 112‐1 cells showed increased binding of the CHT1 inhibitor [3H]hemicholinium‐3 (HC‐3) and greater [3H]choline uptake and ACh synthesis than NIH3T3ChAT 103‐1 cells, a CHT1‐negative control cell line. HC‐3 significantly inhibited ACh synthesis in NIH3T3ChAT 112‐1 cells but did not affect synthesis in NIH3T3ChAT 103‐1 cells. ACh synthesis in NIH3T3ChAT 112‐1 cells was also reduced by amiloride, an inhibitor of organic cation transporters (OCTs) involved in low‐affinity choline uptake, and by procaine and lidocaine, two local anesthetics that inhibit plasma membrane phospholipid metabolism. These results suggest that CHT1 plays a key role in ACh synthesis in NIH3T3ChAT 112‐1 cells and that choline taken up by OCTs or derived from the plasma membrane is also utilized for ACh synthesis in both cholinergic neurons and nonneuronal cholinergic cells, such as lymphocytes. © 2009 Wiley‐Liss, Inc.
Intraneuronal signaling pathways of metallothionein
Authors: Asmussen Johanne Wirenfeldt , Von Sperling Marie Louise , Penkowa Milena
Published: April 2009

Metallothionein (MT) belongs to a family of metal‐binding cysteine‐rich proteins comprising several structurally related proteins implicated in tissue protection and regeneration after injuries and functioning as antiapoptotic antioxidants in neurological disorders. This has been demonstrated in animals receiving MT treatment and in mice with endogenous MT overexpression or null mutation during various experimental models of neuropathology, and also in patients with Alzheimer's disease and amyotrophic lateral sclerosis. Exogenously applied MT increases neurite outgrowth and neuronal survival in rat cerebellar, hippocampal, dopaminergic, and cortical neurons in vitro. In this study, the intraneuronal signaling involved in MT‐mediated neuritogenesis was examined. The MT‐induced neurite outgrowth in cultures of cerebellar granule neurons was dependent on activation of a heterotrimeric G‐protein‐coupled pathway but not on protein tyrosine kinases or on receptor tyrosine kinases. Activation of phospholipase C was necessary for MT‐induced neurite outgrowth, and furthermore it was shown that inhibition of several intracellular protein kinases, such as protein kinase A, protein kinase C, phosphatidylinositol 3‐kinase, Ca2+/calmodulin kinase‐II, and mitogen‐activated protein kinase kinase, abrogated the MT‐mediated neuritogenic response. In addition, exogenously applied MT resulted in a decrease in phosphorylation of intraneuronal kinases implicated in proinflammatory reactions and apoptotic cell death, such as glycogen synthase‐serine kinase 3α, Jun, and signal transducer and activator of transcription 3. This paper elucidates the intraneuronal molecular signaling involved in neuroprotective effects of MT. © 2009 Wiley‐Liss, Inc.
Mice lacking adenylyl cyclase‐5 cope badly with repeated restraint stress
Authors: Kim Kyoung‐Shim , Han Pyung‐Lim
Published: April 2009

Physiological responses to acute stress proceed with the activation of the hypothalamus‐pituitary‐adrenal gland (HPA) system. Many brain regions are known to modulate the HPA axis activation in stress responses, but the detailed neural circuits and signaling system in the upstream of the HPA axis have to be explored further. Type 5 adenylyl cyclase (AC5) is highly concentrated in the dorsal striatum and nucleus accumbens, which are implicated in reward and stress‐related behavior.AC5–/–mice exposed to daily 2‐hr restraint stress for only 3–5 days showed poor stress‐coping responses, including severe body weight loss, poor coat condition, respiratory difficulties, and freezing behavior. Plasma corticosterone levels during 2‐hr stress sessions increased inAC5–/–mice compared with those ofAC5+/+mice. However, neither the corticosterone receptor antagonist RU486 nor the CRH receptor antagonist NBI27914 blocked their poor stress coping, whereas the administration of the GABAAreceptor allosteric modulator diazepam or the D1 dopamine receptor antagonist SCH23390 prior to restraint stress sessions changed their stress‐coping response to the stressedAC5+/+mouse level. Stress‐triggered c‐Fos expression was completely blunted in the dorsal striatum ofAC5–/–. These results suggest that the AC5‐associated signal system and neural network are involved in the regulation of anxiety and stress‐coping response. © 2009 Wiley‐Liss, Inc.
Novel three‐dimensional MRI technique for study of cartilaginous hip surfaces in Legg‐Calvé‐Perthes disease
Authors: Pienkowski David , Resig JoAnne , Talwalkar Vishwas , Tylkowski Chester
Published: April 2009

Treatment of Legg‐Calvé‐Perthes disease (LCPD) may improve if new knowledge can be obtained regarding how articular cartilage changes shape during the course of this disorder. A new technique is presented showing how analyses of magnetic resonance images can be used to quantify the three‐dimensional changes in the femoral and acetabular articulating cartilage surfaces of children with LCPD. Ten male subjects (8 ± 1 years) with unilateral LCPD were enrolled in this IRB approved study. Sets of magnetic resonance images of both hips were obtained at three different times. Three‐dimensional virtual models of the cartilage were created from these images, and mathematical spheres were fit to the articulating surfaces. Five parameters (size, shape deformity (sphericity error), radial growth rate, joint fit, and joint incongruity) were used to quantify cartilage surface shape. Data were analyzed by using a linear mixed‐model. Joint incongruity, i.e., the distance between the centers of the femoral and acetabular spheres, was slightly more than 2.5 times larger (p = 0.001) in LCPD hips than the contralateral normal hips. Cartilage shape deformity was 65% larger in hips with LCPD than in normal hips. Growth rates of the femoral head and the opposing acetabular surface showed that distortion of the femoral surface occurred first and the opposing acetabular surface followed. Mean radial difference (acetabular surface radius minus femoral surface radius) in LCPD hips was less than half (p < 0.01) the value of normal hips. Interobserver variability was ∼10% of the value attributable to LCPD. This is the first known report presenting a technique that quantifies the three‐dimensional size, deformity, growth, fit. and incongruity of the femoral and acetabular articulating cartilaginous surfaces of LCPD and contralateral normal hips. The data obtained support the use of this technique and provide pilot data for a future clinical study of LCPD. Objective assessment of cartilage shape enabled by this technique may aid future diagnoses, enable monitoring of three‐dimensional femoral and acetabular remodeling, and permit quantitative assessment of treatment efficacy. © 2009 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 27: 981–988, 2009
Effect of supplementary manganese on the sporulation of Bacillus endospores analysed by Raman spectroscopy
Authors: Stöckel S. , Meisel S. , Böhme R. , Elschner M. , Rösch P. , Popp J.
Published: April 2009

It is a common practice in microbiology to induce and accelerate sporulation of spore‐forming bacteria by adding small amounts of divalent manganese to the cultivation medium. By micro‐Raman spectroscopy the effect of supplementary divalent manganese during the growth and sporulation of Bacillus spp. bacteria was studied. The spectral alterations in the Raman spectra of single endospores due to this cultivation parameter comprised slight alterations of the bands attributed to intracellular, abundantly present calcium dipicolinate (CaDPA). Those signals suffered a loss of intensity or partial band broadening because of the appearance of new weak signals next to them. Exclusively in Raman spectra of single B. sphaericuss endospores, the band at 1485 cm−1 vanished. The theoretical spectra of CaDPA and manganese dipicolinate (MnDPA) were calculated and compared with the experimental spectra to prove the hypothesis that, while the overall intracellular DPA content decreased, an intracellular assembly of MnDPA in the endospores might also occur. Band shifts of the COO− vibrations in the salt's spectra as well as in the endospore's spectra, and the decrease of the two CaDPA bands, confirmed this proposal. The appearance of the 1030 cm−1 band in all Bacillus spectra as well as the disappearance of the 1485 cm−1 band in the B. sphaericus spectra still needs to be clarified. With the help of two multivariate chemometric methods, these spectral alterations allowed discrimination between single endospores of different Bacillus strains cultivated on normal nutrient agar (NA) and those grown on NA with MnSO4 · xH2O addition. With these investigations, a possible strategy is shown to trace back the cultivation environment of matured single endospores. Utilizing the joint concept of micro‐Raman spectroscopy and chemometric analysis, the differentiation between natively grown endospores and those cultivated in a laboratory with the help of manganous salts as a common sporulation accelerator seems accomplishable. Copyright © 2009 John Wiley & Sons, Ltd.
Monitoring the synthesis of new polymer nanocomposites based on different polyhedral oligomeric silsesquioxanes using Raman spectroscopy
Authors: Sulca Nicoleta Mihaela , Lungu Adriana , Garea Sorina Alexandra , Iovu Horia
Published: April 2009

The kinetic behavior of the urethane dimethacrylate (UDMA) copolymerized and reinforced by different concentrations of polyhedral oligomeric silsesquioxane (POSS) with methacrylic groups was studied through Raman spectroscopy. UDMA‐POSS networks have been synthesized with three different types of POSS, two monofunctional POSS (1‐propylmethacrylate)‐heptaisobutyl substituted (HISO‐POSS) and heptacyclopentyl‐octasiloxan‐1‐yloxy) dimethylsilyl] propyl methacrylate (CPENTYL‐POSS) and one octafunctional POSS‐methacryl substituted (MA‐POSS). In order to show the influence of POSS on the final conversion, the hybrid systems were cured using three types of initiators which decompose at different temperatures: azobisisobutyronitrile (AIBN) (65 °C), benzoyl peroxide (BP) (80 °C) and di‐tert‐butyl peroxide (DTBP) (120 °C). The structure of the hybrid's surface was investigated by X‐ray photoelectron spectroscopy (XPS) and the Tg values were calculated from dynamic mechanical analysis (DMA) tests. Copyright © 2009 John Wiley & Sons, Ltd.
Low humidity after harvest changes the abscission site in bunch cherry tomatoes
Authors: Dvir Orit , Farber Inon , Rom Moran , Rachman Anna , Beno‐Moualem Delila , Meir Shimon , Lichter Amnon
Published: April 2009

BACKGROUND: In bunch cherry tomatoes (BCTs) abscission of the fruit from the bunch, rather than deterioration of fruit determines the life‐span of the produce. Two abscission sites have been characterised: the joint (AJ) in the middle of the pedicel, and at the receptacle (AR) at the fruit‐pedicel interphase. The type of abscission is sensitive to growth conditions; joint abscission is typical of winter harvests whereas receptacle abscission is dominant in summer harvests. The aim of the present study was to determine the effect of relative humidity (RH) in terms of water vapour pressure deficit (WVPD) during storage and shelf life on the course and site of abscission of BCTs.

RESULTS: The rachis composes only about 2% of the bunch weight, and therefore most of the water loss originated from the fruit. When the bunch lost almost 10% of its weight under low humidity, the relative weight of the rachis was reduced to one‐quarter of its original value. Storage at low WVPD resulted in dominance of AJ whereas storage at high WVPD resulted in dominance of AR. BCTs that exhibited primarily AJ after cold storage was prone to either AJ or AR in high or low shelf‐life RH, respectively. BCTs subjected to elevated temperature and high WVPD after harvest developed receptacle abscission.

CONCLUSION: Dehydration of the receptacle abscission zone makes it prone to abscission and this process can be prevented by high‐RH storage. Copyright © 2009 Society of Chemical Industry
α‐Glucosidase and α‐amylase inhibitory activities of phloroglucinal derivatives from edible marine brown alga, Ecklonia cava
Authors: Lee Sang‐Hoon , Yong‐Li  , Karadeniz Fatih , Kim Moon‐Moo , Kim Se‐Kwon
Published: April 2009

BACKGROUND: Diabetes mellitus (DM) is a chronic metabolic disorder characterized by defects in insulin secretion and action, which can lead to damaged blood vessels and nerves. With respect to effective therapeutic approaches to treatment of DM, much effort has being made to investigate potential inhibitors against α‐glucosidase and α‐amylase from natural products. The edible marine brown alga Ecklonia cava has been reported to possess various interesting bioactivities, which are studied here.

RESULTS: In this study, five phloroglucinal derivatives were isolated from Ecklonia cava: fucodiphloroethol G (1), dieckol (2), 6,6′‐bieckol (3), 7‐phloroeckol (4) and phlorofucofuroeckol A (5); compounds 1, 3 and 4 were obtained from this genus for the first time and with higher yield. The structural elucidation of these derivatives was completely assigned by comprehensive analysis of nuclear magnetic spectral data. The anti‐diabetic activities of these derivatives were also assessed using an enzymatic inhibitory assay against rat intestinal α‐glucosidase and porcine pancreatic α‐amylase. Most of these phlorotannins showed significant inhibitory activities in a dose‐dependent manner, responding to both enzymes, especially compound 2, with the lowest IC50 values at 10.8 µmol L−1 (α‐glucosidase) and 124.9 µmol L−1 (α‐amylase), respectively. Further study of compound 2 revealed a non‐competitive inhibitory activity against α‐glucosidase using Lineweaver‐Burk plots.

CONCLUSION: These results suggested that Ecklonia cava can be used for nutritious, nutraceutical and functional foods in diabetes as well as for related symptoms. Copyright © 2009 Society of Chemical Industry
Clustering and compatibility between tourism attractions
Authors: Weidenfeld Adi , Butler Richard W. , Williams Allan M.
Published: April 2009

Cumulative attraction or compatibility is a powerful factor in locational decisions of retail outlets, but it has received little attention in the tourism literature. Existing studies largely ignore the impact of spatial and thematic clustering on compatibility between tourism businesses. This research questions whether and how spatial and thematic clustering are related to tourist movements between visitor attractions. The study in Cornwall, England, is based on in‐depth interviews with tourist attraction managers and key informants, complemented by a survey of 435 tourists. It provides insights into the relationship between the nature of the tourism product, spatial clustering and tourism behaviour. Copyright © 2009 John Wiley & Sons, Ltd.
Genetic polymorphisms in chronic hyperplastic sinusitis with nasal polyposis
Authors: Bernstein Joel M. , Anon Jack B. , Rontal Michael , Conroy Jeffrey , Wang Chong , Sucheston Lara
Published: April 2009

Objectives/Hypothesis:

Although many proinflammatory cytokines have been identified in nasal polyp tissue, the initial trigger that causes this inflammation characterized by edema, lymphocytosis, and eosinophilia, is still unknown. The purpose of the present study is to identify the presence of genetic polymorphisms in proinflammatory, anti‐inflammatory, and chemokine genes that might contribute to genetic susceptibility to chronic hyperplastic sinusitis with nasal polyposis (CHSwNP).

Study Design:

Case control study.

Methods:

Buccal swabs were taken from the left and right oral mucosal surfaces from 179 patients with CHSwNP and 153 nonpolyposis controls with the Purgene DNA purification protocol (Gentra). Genotyping assays for cytokine gene loci were performed on 14 cytokine genes using the iPlex Gold and the Mass Array Compact system (Sequenom, San Diego, CA). Tests of Hardy‐Weinberg equilibrium proportions were performed separately in the cases and controls. Tests for evidence of association between alleles at each single‐nucleotide polymorphism (SNP) and case‐control status were performed using unconditional logistic regression.

Results:

The frequency of the A allele in a SNP located in tumor necrosis factor (TNF)‐α (rs1800629) is significantly different in patients with nasal polyposis versus controls without nasal polyposis, 18.6% and 11.5%, respectively with an individuals' odds of susceptibility to nasal polyps increasing almost two‐fold (odds ratio, 1.86; confidence interval, 1.4–3.09) given at least one copy of the A allele at this SNP. All other cytokine gene polymorphisms of both inflammatory, anti‐inflammatory, and chemokine genes were not statistically different between the two groups.

Conclusions:

TNF‐α‐308, a SNP in the promoter region of this cytokine gene is associated with increased odds of developing nasal polyposis. TNF‐α is a potent immuno‐mediator and proinflammatory cytokine that has been implicated in the pathogenesis of a large number of human diseases. The location of this gene on the short arm of chromosome 6, with the major histocompatibility complex genes and complement, has raised the probability that polymorphism within this locus may contribute to a genetic association of this region of the genome with a wide variety of infectious and autoimmune diseases. Laryngoscope, 2009
Efficacy of microdebrider intracapsular adenotonsillectomy as validated by polysomnography
Authors: Reilly Brian K. , Levin Joshua , Sheldon Stephen , Harsanyi Krisztina , Gerber Mark E.
Published: April 2009

Objectives/Hypothesis:

To evaluate the efficacy of microdebrider intracapsular tonsillectomy (MT) as a treatment for pediatric obstructive sleep apnea (OSA) and sleep disordered breathing.

Study Design:

A retrospective study evaluating polysomnogram outcomes for 26 patients who had undergone MT by a sole surgeon (M.G.) for OSA.

Methods:

Chart review of patients who underwent polysomnograms pre‐ and post‐adenotonsillectomy. This study represents a single pediatric otolaryngologist's experience at two tertiary care medical centers (Children's Memorial Hospital and Evanston Hospital) in the greater Chicago area.

Results:

Statistically significant improvement of both the apnea‐hypopnea index (AHI) and apnea index with P < .0001. All 26 children in the cohort had improved AHI scores following intracapsular tonsillectomy. Statistical analysis was performed using a P value < .05, which was significant.

Conclusions:

MT is an effective means of treating obstructive sleep apnea. Because of its favorable surgical outcomes and minimal morbidity, an increasing number of studies have found MT to be an excellent option for the surgical management of adenotonsillar hypertrophy in pediatric patients with OSA. Laryngoscope, 2009
Macromol. Chem. Phys. 9/2009
Authors: Hadano Shingo , Kishimoto Takuya , Hattori Tomonori , Tanioka Daisuke , Teraguchi Masahiro , Aoki Toshiki , Kaneko Takashi , Namikoshi Takeshi , Marwanta Edy
Published: April 2009

Cover: Four new phenylacetylenes having two hydroxyl groups and an alkyl group with more than six C atoms were found to be suitable for helix‐sense‐selective polymerization. Other phenylacetylenes with shorter alkyl groups gave only insoluble polymers. The longer alkyl chains could stabilize a one‐handed helical structure in solution by effectively forming intramolecular hydrogen bonds. Further details can be found in the article by S. Hadano, T. Kishimoto, T. Hattori, D. Tanioka, M. Teraguchi, T. Aoki,* T. Kaneko, T. Namikoshi, and E. Marwanta on page 717.
Hip flexor fatigue limits walking in Charcot–Marie–Tooth disease
Authors: Ramdharry Gita M. , Day Brian L. , Reilly Mary M. , Marsden Jonathan F.
Published: April 2009

Charcot–Marie–Tooth (CMT) disease results in distal lower limb weakness that affects walking. In this study we assess the role of the hip flexors in compensating for distal weakness while walking and the effects of prolonged walking on these putative compensatory strategies. Eighteen subjects with CMT disease were compared with 14 matched controls while they walked on a treadmill to a predetermined point of perceived effort. A significant reduction was observed in peak hip flexor velocity during walking and hip flexor maximal voluntary contraction. In a second session following selective fatigue of the hip flexors, hip flexor velocity decreased immediately on walking, and walking duration was greatly reduced. This study suggests that hip flexors compensate for distal weakness and that fatigue in the hip flexors can limit walking duration. Treatments directed toward improving proximal muscle strength may therefore help to delay onset of hip flexor fatigue and thus prolong walking duration. Muscle Nerve, 2009
Perceptions of bed days for individuals with chronic illness in extended care facilities
Authors: Fox Mary T. , Sidani Souraya , Brooks Dina
Published: April 2009

We explored perceptions of bed days (defined as staying in bed for 1 or more days per week) in 46 patients receiving extended in‐patient services for chronic illness management. Illness onset or exacerbation (35%), limited mobility (22%), and tiredness (15%) were the most prevalent reasons for initiating bed days. Tiredness (44%), limited mobility (26%), pain (24%), bowel treatment (22), and conserving energy for future activities (20%) were the most prevalent current reasons. Most participants (74%) noted having been involved in decisions concerning bed days and preferred to continue bed days. The results suggest patients schedule bed days to manage several health related symptoms. Based on our findings, nurses could help patients to alternate daily upright activity with rest to mitigate the known consequences of bed days. © 2009 Wiley Periodicals, Inc. Res Nurs Health 32:335–344, 2009
Diagnostic morphometric applicability of confocal laser scanning microscopy in Osteoarchaeology
Authors: Papageorgopoulou C. , Kuhn G. , Ziegler U. , Rühli F. J.
Published: April 2009

The confocal laser scanning microscope (CLSM) has become an essential tool for a wide range of biological and clinical studies and imaging applications. The major imaging modes of the CLSM include single and serial optical sections from thick specimens (100 µm), multiple wavelength images and three‐dimensional reconstruction. Such images provide measurement of length, surface or volume of objects. Surprisingly, this advanced microscopic method has been very rarely used in anthropological research, although numerous clinical and basic science research projects showed its value to study, bone growth, bone micro‐architecture and 3D bone morphometry. We present the basic principles and advantages of CLSM and outline practical aspects of specimen preparation, image collection and digital image processing specifically appropriate for historical bone and hair material. Copyright © 2009 John Wiley & Sons, Ltd.
Boundary value problems in the theory of thermomicrostretch elastic solids
Authors: Svanadze Lika
Published: April 2009

In this paper the linear theory of thermomicrostretch elastic solids is considered. The basic properties of wave numbers of the longitudinal and transverse plane waves are established.The existence of eigenfrequencies of the interior homogeneous boundary value problem (BVP) of steady oscillations is studied. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Survival outcome in childhood ALL: Experience from a tertiary care centre in North India
Authors: Kulkarni K.P. , Marwaha R.K. , Trehan A. , Bansal D.
Published: April 2009

Background

Survival of children with ALL, in developing nations has not kept pace with cure rates in developed countries. Our study was designed to assess survival data and identify risk factors.

Procedure

Data of 762 patients with ALL were analyzed. Information regarding the clinical‐demographic profile, therapy and course of illness were recorded. Status and duration at last follow‐up were utilized to generate Kaplan–Meier survival curves.

Results

The mean age was 5.7 ± 0.23 years (M/F, 3.2:1). Parents of 230 (30.2%) patients opted for no therapy. There were 68 and 60 deaths in induction and remission phases respectively. Besides these, 111 children either defaulted therapy or were lost to follow up. Relapsed disease was documented in 125 cases. The 5‐year OS and EFS was 46% and 43% respectively. Survival analysis, using the Cox multivariate regression, for gender (P = 0.659, CI: 0.852–1.161), age (P = 0.943, CI: 0.725–1.225), symptom‐diagnosis interval (P = 0.002, CI: 1.116–1.668), WCC (P < 0.001, CI: 1.353–1.814) and platelet count (P = 0.001, CI: 0.546–0.849) was performed. Bulk disease (P = 0.049, CI: 0.428–0.986), mediastinal adenopathy (P = 0.045, CI: 1.040–3.697), WCC (P = 0.016, CI: 1.395–2.691), platelet count (P = 0.031, CI: 0.431–0.967) and administration of 2 intensification blocks (P = 0.012, CI: 0.624–0.940) were found to be significant predictors of outcome by multivariate analysis.

Conclusions

The management of ALL requires financial resources and access to quality supportive care. One third of our patients opted for no therapy. The other problem areas were a high proportion of therapy defaulters, lost to follow up and infection related deaths during induction and remission phases. The introduction of remedial measures for resolving the difficulties identified would hopefully improve cure rates in ALL in developing nations. Pediatr Blood Cancer 2009;53:168–173. © 2009 Wiley‐Liss, Inc.
Initial presentation of unscreened children with sickle cell disease: The Toronto experience
Authors: Lieberman Lani , Kirby Melanie , Ozolins Laura , Mosko Jeffrey , Friedman Jeremy
Published: April 2009

Background

The morbidity and mortality related to sickle cell disease (SCD) has decreased since the introduction of newborn screening in the United States. Given the multicultural nature of the Canadian population and the growing African Canadian population, it is concerning that there is no national neonatal screening program for SCD in Canada. The objective of this study was to evaluate the most common manner in which SCD is diagnosed in children when neonatal screening is not available routinely.

Procedure

The study design was a retrospective chart review. All children aged from birth to 18 years with SCD and an admission to the Hospital for Sick Children in Toronto, Canada, between 1978 and 2004 were eligible for inclusion.

Results

Fifty‐two percent of the children with SCD were diagnosed through some form of screening while 48% were diagnosed with symptoms suggestive of their disease. The median age at time of diagnosis was 0.75 years in the “screened” group, and 2 years in the “symptom” group (P < 0.05). The most common symptomatic presentation was with a vaso‐occlusive crisis. Fifteen percent presented with more severe symptoms including acute chest syndrome (5.5%), acute splenic sequestration (5%), sepsis (3.3%), aplastic crisis (1%), priapism (0.5%), meningitis (0.5%), stroke (0.5%), and death (1%).

Conclusions

Fifteen percent of children with undiagnosed SCD presented initially with severe complications of the disease. The morbidity and mortality related to undiagnosed SCD underscores the need for a national neonatal screening program in Canada. Pediatr Blood Cancer 2009;53:397–400. © 2009 Wiley‐Liss, Inc.
Neonatal acute myeloid leukemia in an infant whose mother was exposed to diethylstilboestrol in utero
Authors: Chantrain C.F. , Sauvage D. , Brichard B. , Dupont S. , Poirel H.A. , Ameye G. , De Weer A. , Vandenberghe P. , Detaille T. , Anslot C. , de Cléty S. Clément , Vermylen C.
Published: April 2009

We report on an acute myeloid leukemia in a neonate whose mother was exposed to diethylstilboestrol in utero. The newborn presented with leukemia cutis, hemorrhagic skin lesions, hyperleucocytosis and disseminated intravascular coagulation. A bone marrow examination confirmed the diagnosis of acute monocytic leukemia with a t(11;19) MLL‐ELL fusion transcript. Chemotherapy was initiated but the child developed a bilateral pulmonary infection that led to fatal respiratory distress. This case shows acute myeloid leukemia and the third pediatric leukemia reported after maternal diethylstilboestrol exposure. Pediatr Blood Cancer 2009;53:220–222. © 2009 Wiley‐Liss, Inc.
Clinical course and outcome in children with acute lymphoblastic leukemia and asparaginase‐associated pancreatitis
Authors: Kearney Susan L. , Dahlberg Suzanne E. , Levy Donna E. , Voss Stephan D. , Sallan Stephen E. , Silverman Lewis B.
Published: April 2009

Background

Asparaginase, an agent used in the treatment of acute lymphoblastic leukemia (ALL), is associated with the development of pancreatitis. The clinical course and long‐term outcome of patients experiencing this complication has not been extensively detailed.

Procedure

We reviewed the clinical course for all children with ALL diagnosed with pancreatitis at the Dana‐Farber Cancer Institute/Children's Hospital Boston between 1987 and 2003. The outcome of these patients was compared with that of patients with ALL who did not experience pancreatitis.

Results

Twenty‐eight of 403 children (7%) were diagnosed with pancreatitis. Patients 10–18 years old at diagnosis had 2.4 times the risk of developing pancreatitis compared with younger patients. Pancreatitis typically occurred early in the course of therapy (median 4 weeks after first dose of asparaginase). Ninety‐three percent of affected patients were hospitalized and 57% received parenteral nutrition. No patient developed chronic sequelae or died as a result of pancreatitis. Sixteen (57%) patients were re‐treated with asparaginase, 10 of whom had another episode of pancreatitis. No significant differences in event‐free survival were observed when comparing patients with and without a history of pancreatitis.

Conclusion

Asparaginase‐associated pancreatitis was more common in older children, and caused significant acute morbidity. It tended to occur after the first few doses of asparaginase, suggesting a predisposition to this complication rather than a cumulative drug effect. Re‐treatment with asparaginase after an episode of pancreatitis was associated with a high risk of recurrent pancreatitis. Pediatr Blood Cancer 2009;53:162–167. © 2009 Wiley‐Liss, Inc.