bluuebunny/crossref_metadata_2025_split huggingface dataset:
Expression of the LIM‐homeodomain protein Isl1 in the developing and mature mouse retina
Authors: Elshatory Yasser , Deng Min , Xie Xiaoling , Gan Lin 
Published: May 2007

AbstractThe mammalian retina is comprised of six major neuronal cell types and is subdivided into more morphological and physiological subtypes. The transcriptional machinery underlying these subtype fate choices is largely unknown. The LIM‐homeodomain protein, Isl1, plays an essential role in central nervous system (CNS) differentiation but its relationship to retinal neurogenesis remains unknown. We report here its dynamic spatiotemporal expression in the mouse retina. Among bipolar interneurons, Isl1 expression commences at postnatal day (P)5 and is later restricted to ON‐bipolar cells. The intensity of Isl1 expression is found to segregate the pool of ON‐bipolar cells into rod and ON‐cone bipolar cells with higher expression in rod bipolar cells. As bipolar cell development proceeds from P5–10 the colocalization of Isl1 and the pan‐bipolar cell marker Chx10 reveals the organization of ON‐center bipolar cell nuclei to the upper portion of the inner nuclear layer. Further, whereas Isl1 is predominantly a ganglion cell marker prior to embryonic day (E)15.5, at E15.5 and later its expression in nonganglion cells expands. We demonstrate that these Isl1‐positive, nonganglion cells acquire the expression of amacrine cell markers embryonically, likely representing nascent cholinergic amacrine cells. Taken together, Isl1 is expressed during the maturation of and is later maintained in retinal ganglion cells and subtypes of amacrine and bipolar cells where it may function in the maintenance of these cells into adulthood. J. Comp. Neurol. 503:182–197, 2007. © 2007 Wiley‐Liss, Inc.
Secondary Metabolites Isolated from an Endophytic Phoma sp. – Absolute Configuration of Tetrahydropyrenophorol Using the Solid‐State TDDFT CD Methodology
Authors: Krohn Karsten , Farooq Umar , Flörke Ulrich , Schulz Barbara , Draeger Siegfried , Pescitelli Gennaro , Salvadori Piero , Antus Sándor , Kurtán Tibor 
Published: May 2007

AbstractThe known macrolide pyrenophorol (synonym helmidiol) (1), the new 2,3,10,11‐tetrahydropyrenophorol (3), and (4S,7R)‐4,7‐dihydroxyoctanoic acid (4), the monomeric acid of the sixteen‐membered cyclic diolide 1, were isolated from an endophytic Phoma sp. The relative configuration of tetrahydropyrenophorol (3) was confirmed by X‐ray single crystal analysis and its absolute configuration determined by the solid‐state TDDFT CD methodology. Compounds 1 and 4 show antifungal activity and the acid 4 is also an algicide. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
Voltammetric Determination of 3‐Nitrofluoranthene and 3‐Aminofluoranthene at Boron Doped Diamond Thin‐Film Electrode
Authors: Cizek Karel , Barek Jiri , Fischer Jan , Peckova Karolina , Zima Jiri 
Published: May 2007

AbstractThe voltammetric behavior of 3‐nitrofluoranthene and 3‐aminofluoranthene was investigated in mixed methanol‐water solutions by differential pulse voltammetry (DPV) at boron doped diamond thin‐film electrode (BDDE). Optimum conditions have been found for determination of 3‐nitrofluoranthene in the concentration range of 2×10−8–1×10−6 mol L−1, and for determination 3‐aminofluorathnene in the concentration range of 2×10−7–1×10−5 mol L−1, respectively. Limits of determination were 3×10−8 mol L−1 (3‐nitrofluoranthene) and 2×10−7 mol L−1 (3‐aminofluoranthene).
Carbon Paste Electrode Modified with Functionalized Nanoporous Silica Gel as a New Sensor for Determination of Silver Ion
Authors: Javanbakht Mehran , Ganjali Mohammad Reza , Norouzi Parviz , Badiei Alireza , Hasheminasab Abed , Abdouss Majid 
Published: May 2007

AbstractA new dipyridyl‐functionalized silica gel (DPSG) was synthesized. The potentiometric response of silver ion was investigated at a carbon paste electrode chemically modified with functionalized nanoporous silica gel. The electrodes with a DPSG proportions of 10.1% (w/w), showed very stable potential. Calibration plots with Nernstian slopes for Ag+ were observed, 58.7 (±0.9) mV decade−1, over a wide linear range of concentration (5.0×10−7 to 1.0×10−1 M). The electrode has a detection limit of 1.0×10−7 M. The selectivity coefficients measured by the match potential method in acetate buffer, pH 5.5, were investigated. The electrode has fast response time, high performance, high sensitivity in wide cation activity ranges, and good long term stability (more than 6 months). The method was satisfactory and used to determine the concentration of silver ion in waste waters contaminated by this metal.
DNA Determination in the Presence of Copper in Diluted Alkaline Electrolyte by Adsorptive Stripping Voltammetry at the Mercury Film Electrode
Authors: Farias Percio Augusto Mardini , Castro Arnaldo Aguiar , de Luca Rebello Wagener Angela , Junqueira Astrid Altamirano 
Published: May 2007

AbstractA stripping method for the determination of single‐stranded DNA in presence of copper at the submicromolar concentration levels is described. The method is based on controlled adsorptive accumulation of adenine (from acid‐treated DNA) at thin‐film mercury electrode followed by linear scan voltammetry measurement of the surface species. Optimum experimental conditions were found to be the use of a 5.0×10−3 M NaOH solution, an accumulation potential of −0.40 V and a scan rate of 200 mV s−1. The response of adenine–copper is linear over the concentration range 50–250 ppb. For an accumulation time of 15 minutes, the detection limit was found to be 4 ppb. The more convenient relation to measuring the ssDNA in presence of metals and nitrogenated bases were also investigated. The utility of the method is demonstrated by the presence of adenosine‐triphosphate (ATP) and amino acids.
A Calibration‐Base Method for the Evaluation of the Detection Limit of an Electrochemical Biosensor
Authors: Lavagnini Irma , Antiochia Riccarda , Magno Franco 
Published: May 2007

AbstractThe method based on the confidence limits of a regression straight line is applied to the linear portion of the calibration curve of a biosensor in order to determine the limit of detection. A practical application gives a detection limit of an ethanol biosensor greater than that calculated by using the method of the signal‐to‐noise‐ratio, S/N=3, but the value is more reliable because it accounts for the variability in the response at analyte additions. A simple approximation of the method is also presented.
Voltammetry of Osmium End‐Labeled Oligodeoxynucleotides at Carbon, Mercury, and Gold Electrodes
Authors: Trefulka Mojmír , Ferreyra Nancy , Ostatná Veronika , Fojta Miroslav , Rivas Gustavo , Paleček Emil 
Published: May 2007

AbstractVoltammetric behavior of oligodeoxynucleotide (ODN) 5′‐T40 (GAA)7–3′ end‐labeled with osmium tetroxide,2,2‐bipyridine [Os(VIII)bipy] was compared with Os(VIII)bipy‐base‐ and with Os(VI)bipy‐sugar‐modified thymine ribosides. Cyclic voltammograms of Os(VIII)bipy‐modified ODN at mercury and carbon electrodes were similar but not identical to those of Os(VIII)bipy‐modified thymine riboside. Treatment of the ODN with Os(VI)bipy did not result in the ODN modification, in agreement with the known specificity of the reagent to the sugar cis‐diols. We show that in addition to mercury and carbon electrodes, the gold electrode can be used to detect Os(VIII)bipy‐labeled ODN. Comparison of voltammetric behavior of end‐labeled ODN using three types of electrodes most frequently used in DNA analysis may help to optimize electrochemical DNA sensors.
Electrochemical Detection of 2‐Naphthol at a Glassy Carbon Electrode Modified with Tosflex Film
Authors: Tsai Ming‐Chih , Chen Po‐Yu 
Published: May 2007

AbstractIn this study, a Tosflex (a perfluoro‐anion‐exchange membrane) modified glassy carbon electrode has been used to detect 2‐naphthalenol (2‐naphthol) in aqueous solutions in order to demonstrate the electroanalytical application of Tosflex. 2‐naphthol polymerizes upon electrochemical oxidation at a glassy carbon electrode; however, the current related to this oxidation is too small for analytical purpose at low concentration level. A Tosflex polymer modified glassy carbon electrode (TFGCE) was found of having capability to improve the detection limit because 2‐naphthol molecules deprotonated in basic solutions to form 2‐naphtholate anions that were accumulated to TFGCE by the anion‐exchange characteristic of Tosflex. The accumulated 2‐naphtholate anions were determined with the following differential pulse voltammetry. With 3 minutes accumulation at +0.05 V, the dependence of oxidation current versus concentration was linear from 8×10−7 M to 1×10−5 M with a regression coefficient of 0.999 and a detection limit of 2×10−7 M. Unlike many other anion‐exchange polymer modified electrodes, the TFGCE is stable at highly basic condition.
Evaluation of Bayesian models for focused clustering in health data
Authors: Ma Bo , Lawson Andrew B. , Liu Yuan 
Published: May 2007

AbstractThis paper examines the ability of Bayesian hierarchical models to recover evidence of disease risk excess around a fixed location. This location can be a putative source of health hazard, such as an incinerator, mobile phone mast or dump site. While Bayesian models are convenient to use for modeling, it is useful to consider how well these models perform in the true risk scenarios. In what follows, we evaluate the ability of these models to recover the true risk under simulation. It is surprising that the resulting posterior parameters estimates are heavily biased. Using the credible intervals for distance decline parameter to assess ‘coverage or power’ of detecting distance effect, the ‘power’ decreases with increasing correlation in the background population effect. The inclusion of correlated heterogeneity in models does affect the ability of the models to detect the stronger distance decline scenarios. The uncorrelated heterogeneity seems little affect this ability however. Copyright © 2007 John Wiley & Sons, Ltd.
Male gender is associated with greater cerebral hypometabolism in frontotemporal dementia: evidence for sex‐related cognitive reserve
Authors: Perneczky Robert , Diehl‐Schmid Janine , Förstl Hans , Drzezga Alexander , Kurz Alexander 
Published: May 2007

AbstractBackgroundNeuropathological studies suggest that the association between neurodegenerative brain damage and clinical symptoms may be stronger in women than in men; therefore women are more likely to express neurodegeneration as clinical dementia. Furthermore, a recent 18F‐FDG PET study explored gender differences in the regional cerebral metabolic rate of glucose (rCMRglc) in patients with Alzheimer's disease and found that, at the same level of severity of cognitive impairment, men showed a significantly greater hypometabolism than women. This suggests that men can compensate more pathology than women.ObjectiveTo test the hypothesis that cerebral metabolic deficits due to neurodegeneration are more pronounced in men than in women with frontotemporal dementia (FTD), controlling for cognitive impairment.MethodsTwenty‐nine patients with FTD (20 men, nine women) underwent an extensive clinical examination and 18F‐FDG PET imaging at a university‐based outpatient unit for cognitive disorders. An analysis of covariance (with age, total score of the CERAD neuropsychological battery, and years of school education as co‐variates) was conducted to identify gender differences in glucose metabolism.ResultsFrontal cortical regions were identified where rCMRglc was significantly reduced in men as compared with women. These regions were located in the left middle, superior, and inferior frontal gyri and the right anterior cingulate, and superior frontal gyri (p < 0.001 uncorrected for multiple comparisons).ConclusionThe same level of severity of cognitive symptoms is associated with a more pronounced functional brain damage in male than in female patients with FTD, suggesting a greater degree of cognitive reserve in men. Copyright © 2007 John Wiley & Sons, Ltd.
Evaluation of the effect of a life review group program on self‐esteem and life satisfaction in the elderly
Authors: Chiang Kai‐Jo , Lu Ru‐Band , Chu Hsin , Chang Yue‐Cune , Chou Kuei‐Ru 
Published: May 2007

AbstractObjectiveThis study was aimed at evaluating whether a Life Review Group Program (LRGP) improved the self‐esteem and life satisfaction in the elderly.MethodsThis randomized, controlled trial consisted of 75 elderly males from a Veterans' Home in Northern Taiwan, 36 of whom were in the experimental group and 39 of whom were in the control group. The subjects in the experimental group participated in an 8‐week LRGP. Data were collected before and after the LRGP and again 1 month after the end of the program.ResultsThe study subjects had a mean age of 78.13 years. The generalized estimating equation was used to compare alterations in the self‐esteem and life satisfaction of the elderly before and after the intervention. The alterations in self‐esteem and life satisfaction in the experimental group after the LRGP were significantly improved compared to the control group. One month after the LRGP was completed, the self‐esteem and life satisfaction of the experimental group continued to improve when compared with pre‐intervention levels.ConclusionsBased on these results, the LRGP can potentially improve the self‐affirmation, confidence, and self‐esteem of the elderly and promote short‐term life satisfaction. The results of this study provide a model for clinical evidence‐based therapy, serving as a reference for related studies and evaluation of health‐promoting programs, as well as improving the health and quality of care of the elderly. Copyright © 2007 John Wiley & Sons, Ltd.
Genetic research into Alzheimer's Disease: a European focus group study on ethical issues
Authors: van der Vorm Anco , Rikkert Marcel Olde , Vernooij‐Dassen Myrra , Dekkers Wim 
Published: May 2007

AbstractBackgroundNowadays, there is an increasing interest in the heritable aspects of Alzheimer's Disease (AD). The ethical implications of this kind of research are also attracting attention. However, relatively few open‐ended qualitative studies have been carried out to study these aspects.ObjectiveTo explore and analyse ethical issues raised by genetic research into AD.MethodsA modified focus group technique.ResultsParticipants stressed the importance of relatives in genetic research and suggested a family consent procedure. The consent procedure ought to be more uniform within Europe and should allow for variation in the types of research being done. The long‐term results of genetic research into AD are expected to be positive while the short‐term results seem likely to be negative. The perception of AD as a disease could be changed by the results from genetic research into AD, and this could have effects at the individual level (feelings of guilt and responsibility for one's own health).Conclusions(1) The role of the family in genetic AD research differs from its role in other biomedical research into AD. The development of a family consent procedure might solve some informed consent problems. (2) Negative social consequences of genetic AD research are expected in the short term, but there are hopes of positive consequences in the long term. Copyright © 2007 John Wiley & Sons, Ltd.
Ginkgo biloba is not a smart drug: an updated systematic review of randomised clinical trials testing the nootropic effects of G. biloba extracts in healthy people
Authors: Canter PH , Ernst E. 
Published: May 2007

AbstractHere, we update our earlier systematic review of 2001, which critically evaluated the data from clinical trials to determine whether Ginkgo biloba enhances cognitive function in healthy subjects. Literatures searches of six computerised databases, updated to January 2007, were made for randomised, placebo‐controlled, double‐blind clinical trials of the effects of standardised Ginkgo biloba (G. biloba) extracts on cognitive function in healthy subjects under the age of 60 years. Trials published in any language were included, and data were extracted independently by the two authors following a standardised protocol.We include 15 randomised clinical trials of which 7 are single‐dose studies and 8 are longer term studies with treatment periods ranging from 2 days to 13 weeks. Three single dose studies and 4 longer term studies are newly included. Several of the studies have methodological flaws. A number of the acute studies used multiple outcomes and report positive effects on one or more of these at particular time points with particular doses but these findings are either not replicated, or are directly contradicted by other studies. The evidence from longer term studies is largely negative. Of those studies which measured subjective effects, only one of five acute studies and one of six longer term studies reported any significant positive results. Overall, and in line with our previous conclusions, we have found no convincing evidence from randomised clinical trials for a robust positive effect of G. biloba ingestion upon any aspect of cognitive function in healthy young people, after either acute or longer term administration. Copyright © 2007 John Wiley & Sons, Ltd.
Coffee price volatility in Ethiopia: effects of market reform programmes
Authors: Gemech Firdu , Struthers John 
Published: May 2007

AbstractThis study presents the results of an empirical investigation into the effects of market reform programmes in Ethiopia and their impact on the volatility of coffee prices. The study covers the period from 1982 to the end of 2001, though its main focus is on the period after the commencement of the reforms in 1992. Using the Generalised Autoregressive Conditional Heteroskedasticity (GARCH) techniques, we argue that there is evidence that Ethiopia experienced a significant increase in coffee price volatility after the adoption of the market‐oriented reform programmes. This is consistent with much of the literature. The econometric evidence presented in the paper, suggests that the market reform programmes were a significant cause of the increased volatility after 1992. The authors also suggest a number of possible policy responses to the price volatility, including strengthening the role of smallholder producer associations; and the possibility of adopting appropriate risk‐management strategies. However, the institutional and structural characteristics of coffee production in Ethiopia within the global market for coffee may mitigate against the successful implementation of such policies. The fact that Ethiopia is a price‐taker in this market and is therefore prone to external shocks in coffee prices over which it has little control or influence means that the country will continue to be highly vulnerable to the natural cycles that are endemic in the production of such primary commodities as coffee. Copyright © 2007 John Wiley & Sons, Ltd.
Understanding the Performance of Biomaterials through Molecular Modeling: Crossing the Bridge between their Intrinsic Properties and the Surface Adsorption of Proteins
Authors: Raffaini Giuseppina , Ganazzoli Fabio 
Published: May 2007

AbstractMolecular modeling and computer simulations can yield significant new insight at the atomistic level about the performance of biomaterials in a biological environment. In this paper, we review our approach to a consistent theoretical picture of the bulk and surface properties of biomaterials. The predicted properties do encompass in particular the mechanical behavior and the surface hydration of these materials, and the surface physisorption of proteins, or polypeptides in general. The behavior of nanomaterials such as the carbon allotropes, nanotubes and fullerenes, in a biological environment is also briefly considered.magnified image
Evaluating the In Vitro and In Vivo Efficacy of Nano‐Structured Polymers for Bladder Tissue Replacement Applications
Authors: Pattison Megan , Webster Thomas J. , Leslie Jeffrey , Kaefer Martin , Haberstroh Karen M. 
Published: May 2007

AbstractBladder cancers requiring radical cystectomy, along with congenital and acquired disorders which result in obstruction of the bladder, necessitate surgical measures (including augmentation); such diagnoses bring a clinical need for effective bladder replacement implant designs. Many recent approaches for the design of soft tissue replacement materials have relied on the use of synthetic polymeric substances; unfortunately, the optimal soft tissue implant material is yet to be found. This may, in part, be because current polymeric formulations fail to sufficiently biomimic the neighboring bladder tissue. This study took a brand new approach in designing the next generation of tissue‐engineered bladder constructs through the use of nanotechnology, or materials with nanometer (less than 100 nm) surface features. Results provided evidence that nano‐structured polymeric scaffolds (specifically, PLGA and PU) created using chemical etching techniques are capable of enhancing the human bladder smooth muscle cell adhesion, proliferation, and the production of extracellular matrix (ECM) proteins. Preliminary in vivo results also speak to the usefulness of such nano‐structured materials. In combination, these findings suggest that nano‐dimensional PLGA and PU scaffolds are promising replacement materials for the human bladder wall.magnified image
Designer Self‐Assembling Peptide Scaffolds for 3‐D Tissue Cell Cultures and Regenerative Medicine
Authors: Gelain Fabrizio , Horii Akihiro , Zhang Shuguang 
Published: May 2007

AbstractBiomaterial science has made enormous progress in the last few decades. Nonetheless, innovative biomaterials are still urgently needed to providein vitrocell‐culture models that more closely resemble three‐dimensional (3‐D) cell interactions and cyto‐architectures in bodies and tissues. In this review, the recent advances toward this goal through molecular engineering of various designer self‐assembling peptide scaffolds are discussed. These peptide scaffolds can be commercially and custom‐tailor synthesized materials with high purity and may be not only useful for specific 3‐D tissue cell cultures but also for tissue repair and regenerative therapies. Furthermore, these designer self‐assembling peptide scaffolds have recently become powerful tools for regenerative medicine to repair nervous tissue, to stop bleeding in seconds, to repair infarctuated myocardia, as well as being useful medical devices for slow drug release.magnified image
New Photocurable Acrylic/Silsesquioxane Hybrid Optical Materials: Synthesis, Properties, and Patterning
Authors: Su Hung‐Wen , Chen Wen‐Chang , Lee Wen‐Chin , King Jinn‐Shing 
Published: May 2007

AbstractSynthesis, properties, and patterning of new acrylic/silsesquioxane hybrid materials are reported. PMA‐functionalized PHSSQ was synthesized by hydrosilylation and then formulated with acrylate monomer mixtures to yield the photocurable materials. Experiments suggest that the thermal/mechanical properties of the parent acrylic polymers could be significantly enhanced by incorporating nano‐sized silsesquioxane moieties. The refractive index and optical loss were reduced by increasing the silsesquioxane content. The hybrid materials could be photocured and developed a Y‐shape channel pattern; potential applications include uses in patterned electronic and optoelectronic devices.magnified image