bluuebunny/crossref_metadata_2025_split huggingface dataset:
Spermine induces cell death in cultured human embryonic cerebral cortical neurons through N‐methyl‐D‐aspartate receptor activation
Authors: de Vera Nuria , Martínez Emili , Sanfeliu Coral 
Published: October 2007

AbstractThe polyamines putrescine, spermidine, and spermine play important roles in cell proliferation, differentiation, and modulation of ion channel receptors. However, the function of increased concentrations of these compounds in brain injury and disease is unclear, in that they have been proposed as being both neuroprotective and neurotoxic. The effects of spermine and putrescine were studied in human primary cerebral cortical cultures containing both neurons and glia. No toxic effects were induced at 8 days in vitro (DIV) by either of the two polyamines at concentrations ranging from 0.3 μM to 2 mM. However, when the oxidative metabolism of spermine that generates toxic byproducts was induced by the presence of fetal calf serum, spermine caused cellular death with an LC50 of approximately 50 μM. At 14 DIV, the coapplication of spermine 2 mM and glutamate 5 mM induced neuron cell death, but the effect of applying both components separately was null. Both spermine and glutamate were toxic to older neurons (26–42 DIV cultures), and here the coapplication of glutamate was found always to intensify the effect of spermine. Spermine showed greater toxicity than glutamate in neurons. Another effect observed is that glutamate, but not spermine, induced astrocyte swelling. Spermine toxicity was inhibited by both MK801 and ifenprodil, indicating a mechanism involving N‐methyl‐D‐aspartate (NMDA) receptor activation. Moreover, a strong spermine modulation of the NMDA receptor was demonstrated by the inhibition of glutamate toxicity by ifenprodil. Putrescine induced minor effects also as a neurotoxic agent. In conclusion, neuronal death by spermine can be induced by its toxic byproducts as well as through NMDA receptor action. The present results confirm the potentially harmful role of the polyamines in excitotoxicity‐related human disorders. © 2007 Wiley‐Liss, Inc.
Ethanol promotes endoplasmic reticulum stress‐induced neuronal death: Involvement of oxidative stress
Authors: Chen Gang , Ma Cuiling , Bower Kimberly A. , Shi Xianglin , Ke Zunji , Luo Jia 
Published: October 2007

AbstractOne of the most devastating effects of ethanol exposure during development is the loss of neurons in selected brain areas. The underlying cellular/molecular mechanisms remain unclear. The endoplasmic reticulum (ER) is involved in posttranslational protein processing and transport. The accumulation of unfolded or misfolded proteins in the ER lumen triggers ER stress, which is characterized by translational attenuation, synthesis of ER chaperone proteins such as GRP78, and activation of transcription factors such as ATF4, ATF6, and CHOP. Sustained ER stress ultimately leads to cell death. ER stress response can be induced experimentally by treatment with tunicamycin and thapsigargin. Using SH‐SY5Y neuroblastoma cells and primary cerebellar granule neurons as in vitro models, we demonstrated that exposure to ethanol alone had little effect on the expression of markers for ER stress; however, ethanol drastically enhanced the expression of GRP78, CHOP, ATF4, ATF6, and phosphorylated PERK and eIF2α when induced by tunicamycin and thapsigargin. Consistently, ethanol promoted tunicamycin‐ and thapsigargin‐induced cell death. Ethanol rapidly caused oxidative stress in cultured neuronal cells; antioxidants blocked ethanol's potentiation of ER stress and cell death, suggesting that the ethanol‐promoted ER stress response is mediated by oxidative stress. CHOP is a proapoptotic transcription factor. We further demonstrated that CHOP played an important role in ethanol‐promoted cell death. Thus, the effect of ethanol may be mediated by the interaction between oxidative stress and ER stress. © 2007 Wiley‐Liss, Inc.
Dye coupling in developing vestibular nuclei
Authors: Shao M. , Gottesman‐Davis A. , Popratiloff A. , Peusner K.D. 
Published: October 2007

AbstractThe chick tangential nucleus is a major vestibular nucleus whose principal cells participate in the vestibular reflexes. During development, most mature vestibular nucleus neurons must acquire repetitive firing of action potentials on depolarization and spontaneous spike activity to process signals effectively. In the chicken, these properties emerge gradually in the embryo, starting the week before (E13, E16) and continuing through the first week after hatching (H7). Since gap junction‐mediated cell coupling may influence the emergence of neuronal excitability, we investigated whether neuron–neuron and neuron–glia coupling are present in this morphologically distinctive vestibular nucleus during the period for establishing signal processing. In brain slices, principal cells were injected with biocytin in the whole‐cell configuration and visualized via confocal imaging at E13, E16, and H7. The incidence of dye coupling between the injected principal cell and neurons was 42% at E13, 75% at E16, and 7% at H7, whereas the incidence of dye coupling with glia was 100% at both embryonic ages but decreased to 27% by H7. For each injected principal cell at E13, one coupled neuron and 35 coupled glia were detected, whereas three coupled neurons and 12 coupled glia were observed at E16, and few if any coupled neurons and glia were detected at H7. These results suggest that neuron–neuron and neuron–glia coupling are developmentally regulated and present before, but not after, the onset of mature signal processing by these neurons. Thus, transient neuron–neuron and neuron–glia coupling may both play roles in establishing excitability in vestibular nucleus neurons during development. © 2007 Wiley‐Liss, Inc.
Increasing gamma‐ and delta‐tocopherols in oils improves oxidative stability
Authors: Warner Kathleen 
Published: October 2007

AbstractOver the past two decades, plant geneticists have revolutionized how fatty acid compositions of vegetable oils are optimized to improve oxidative stability and functionality. Now, the expertise of plant geneticists is reaching beyond altering fatty acids to changing other oil components such as tocopherols. Basic lipid research on optimizing tocopherol profiles and ratios in vegetable oils is providing information for geneticists to breed the next generation of oxidatively stable vegetable oils. This review will discuss three studies; first, a basic study to determine the oxidative stability provided by the addition of pure gamma and delta tocopherols to oils treated to remove natural tocopherols; second, a practical study to evaluate the oxidative stability of mid‐oleic sunflower oil from seeds modified by plant breeding to contain high amounts of γ‐ and δ‐tocopherols; and third, a frying test to determine the effects of gamma tocopherol addition.
3D CT angiography of abdominal wall vascular perforators to plan DIEAP flaps
Authors: Rosson Gedge D. , Williams Christopher G. , Fishman Elliot K. , Singh Navin K. 
Published: October 2007

AbstractPurpose: Since the first report of TRAM flap reconstruction, there have been numerous studies to reduce complications of elective breast reconstruction. Current methods of preoperative perforator localization can be time‐consuming, inaccurate, and imprecise. Thus, we sought to evaluate ultra‐high resolution 3D CT angiography for the preoperative mapping of DIEAP flap perforating vessels. Methods: We reviewed all perforator‐based breast reconstructions performed over a 5‐month period. Candidates for DIEAP flap reconstruction were sent for a focused CT scan of the abdominal wall, using the 64 slice multi‐detector CT scanner. Results: This article presents our first 23 flaps in 17 patients with preoperative ultra‐high resolution 3D CT angiography. The reconstruction plan changed in three patients (18%). There was one take‐back for venous congestion, but no partial or total flap loss. Conclusions: Preoperative perforator flap planning for breast reconstruction utilizing 3D CT angiogram is safe, easy to read, and can change the operative plan. © 2007 Wiley‐Liss, Inc. Microsurgery, 2007.
Fat cell invasion in long‐term denervated skeletal muscle
Authors: Rodrigues Antonio de Castro , Andreo Jesus Carlos , Júnior Geraldo Marco Rosa , dos Santos Nícolas Bertolaccini , Moraes Luis Henrique Rapucci , Lauris José Roberto P. 
Published: October 2007

AbstractThere are several differences between red and white muscles submitted to different experimental conditions, especially following denervation: a) denervation atrophy is more pronounced in red than white muscles; b) the size of the fibers in the red muscles does not vary between different parts of the muscle before and after denervation, when compared to white muscles; c) the regional difference in the white muscles initially more pronounced after denervation than red muscle; d) red muscle fibers and fibers of the deep white muscle present degenerative changes such as disordered myofibrils and sarcolemmal folds after long‐term denervation; e) myotube‐like fibers with central nuclei occur in the red muscle more rapidly than white after denervation. Denervation of skeletal muscles causes, in addition to fibers atrophy, loss of fibers with subsequent regeneration, but the extent of fat cell percentage invasion is currently unknown. The present article describes a quantitative study on fat cell invasion percentage in red m. soleus and white m. extensor digitorum longus (EDL) rat muscles at 7 weeks for up to 32 weeks postdenervation. The results indicate that the percentage of fat cells increase after denervation and it is steeper than the age‐related fat invasion in normal muscles. The fat percentage invasion is more pronounced in red compared with white muscle. All experimental groups present a statistically significant difference as regard fat cell percentage invasion. © 2007 Wiley‐Liss, Inc. Microsurgery, 2007.
Polycondensation Kinetics of Lactic Acid
Authors: Harshe Yogesh M. , Storti Giuseppe , Morbidelli Massimo , Gelosa Simone , Moscatelli Davide 
Published: October 2007

AbstractThe direct polycondensation of D,L‐lactic acid in the absence and presence of different catalysts at various temperatures has been studied experimentally. Two types of reactions were carried out, one under closed conditions to estimate the equilibrium constant and the other under flow of nitrogen to estimate the polymerization rate constant. A mathematical model was developed based on a suitable kinetic scheme for polycondensation reaction accounting for the rate of water removal. The effects of different operating conditions (temperature and pressure) on the average molecular weight of the polymer have been explored through experiments and model simulations.magnified image
“Living” Free Radical Polymerization in Tubular Reactors. I. Modeling of the Complete Molecular Weight Distribution Using Probability Generating Functions
Authors: Asteasuain Mariano , Soares Matheus , Lenzi Marcelo K. , Cunningham Michael , Sarmoria Claudia , Pinto José Carlos , Brandolin Adriana 
Published: October 2007

AbstractThis is the first of a series of works aiming at developing a tool for designing “living” free radical polymerization processes in tubular reactors, in order to achieve tailor‐made MWDs. A mathematical model of the nitroxide‐mediated controlled free radical polymerization is built and implemented to predict the complete MWD. It is shown that this objective may be achieved accurately and efficiently by means of the probability generating function (pgf) transformation. Comparison with experimental data is good. The potential of the resulting model for optimization activities involving the complete MWD is also shown.magnified image
Normal axonal ion channel function in large peripheral nerve fibers following chronic ciguatera sensitization
Authors: Vucic Steve , Kiernan Matthew C. 
Published: October 2007

AbstractAlthough the acute clinical effects of ciguatera poisoning, due to ingestion of ciguatoxin, are mediated by activation of transient Na+ channels, the mechanisms underlying ciguatera sensitization remain undefined. Axonal excitability studies were performed by stimulating the median motor and sensory nerves in two patients with ciguatera sensitization. Excitability parameters were all within normal limits, thereby arguing against dysfunction of axonal membrane ion channels in large‐diameter fibers in ciguatera sensitization. Muscle Nerve, 2007
Three‐dimensional mapping of lingual myoarchitecture by diffusion tensor MRI
Authors: Kim Sungheon , Barnett Alan S. , Pierpaoli Carlo , Chi‐Fishman Gloria 
Published: October 2007

AbstractThis study was performed to assess the feasibility of investigating the complex lingual myoarchitecture through segmentation of muscles from diffusion tensor imaging (DTI) data. The primary eigenvectors were found to be adequate for delineating the superior and inferior longitudinalis, genioglossus, and hyoglossus. The tertiary eigenvector orientations effectively revealed the homogeneous and systematic change of muscle orientation in the tongue core. In the longitudinalis near the tongue tip, the secondary eigenvectors were oriented in the radial direction. Lingual muscles were segmented using two methods: modified directional correlation (DC) and tensor coherence (TC) methods. The DC method, based on one eigenvector, was found to be inadequate for lingual muscle segmentation, whereas the TC method, based on the tensor shape and orientation, was used successfully to segment most lingual muscles. The segmentation result was used to report the diffusion tensor properties of individual lingual muscles. Also found was a continuous change in skewness of the intrinsic tongue core from negative in the anterior region to positive in the posterior region. DTI and the proposed segmentation method provide an adequate means of imaging and visualizing the complex, compartmentalized musculature of the tongue. The potential for in vivo research and clinical applications is demonstrated. Copyright © 2007 John Wiley & Sons, Ltd.
A Hamiltonian particle method for non‐linear elastodynamics
Authors: Suzuki Yukihito , Koshizuka Seiichi 
Published: October 2007

AbstractParticle methods are meshless simulation techniques in which motion of continua is approximated by discrete dynamics of a finite number of particles. They have a great degree of flexibility, for instance, in dealing with complex large deformations or the fragmentation of solids. In this paper, a particle method for non‐linear elastodynamics of compressible and incompressible materials is developed based on a discretization of the Lagrangian from which the governing equations of elastodynamics are derived using the principle of least action. The discretized Lagrangian leads to a finite‐dimensional Hamiltonian system via the Legendre transformation. If the material is incompressible, the Hamiltonian system is accompanied by holonomic constraints. Depending on whether the material is compressible or incompressible, the symplectic scheme adopted for numerical time integration is either the Störmer/Verlet scheme or the RATTLE method, respectively. The resulting particle method inherits the symplectic structure possessed by the governing equations of elastodynamics. In the case of incompressible materials, incompressibility is strictly enforced at each time step. Some numerical tests indicate the excellence of the method for conservation of mechanical energy besides that of linear and angular momenta. Copyright © 2007 John Wiley & Sons, Ltd.
The theologies of transparency in Europe: the limits and possibilities of ‘fusion’ in the EU transparency regime
Authors: Billet Steven 
Published: October 2007

Abstract

The consideration of a transparency regime for the European Union has stimulated considerable response from the Brussels lobbying community. Somewhat predictably, the responses have congregated about two poles: one represented by a strident group of reform activists calling for complete openness with a strong legal component, the other taking a minimalist self‐regulatory approach to the most fundamental issues. The basic positions of the competing sides seem to be immovable; embraced with all the fervour of religious ‘true believers’. At first blush the possibility for a meaningful compromise seems remote. However, the submissions may offer a limited way forward based on a fusion of principles held by many on both sides of the issue.
Copyright © 2007 John Wiley & Sons, Ltd.
The determinants of corporate political strategy in Chinese transition
Authors: Tian Zhilong , Deng Xinming 
Published: October 2007

AbstractCorporate political strategy (CPS) formulation in Chinese transition is an area with little empirical work. We fill this gap validly and the primary focus of this study is to examine the firm‐ and industry‐level factors influencing Chinese firms' political strategy choice. Empirical support is found for the taxonomy of corporate political strategies in Chinese transition—that is direct participation strategy, financial incentive strategy, prolocutor strategy, institution innovation strategy, government association strategy and government involvement strategy. The results indicate that there is no consistently significant firm‐ and industry‐level predictor of all six political strategies and we explore what determinants are related to each specific decision independently. We also verify the random effects of industry‐level variables and our hypotheses are tested through using general evaluation equations (GEEs). Our study aims to be helpful to point managers toward both industrial environments and internal resources to consider when making appropriate political strategy choices and thus improve Chinese firms' strategy management level. Some implications of findings are also discussed finally.Copyright © 2007 John Wiley & Sons, Ltd.
Managed Care in the USA: origins, HMO strategies and the marketing of health services
Authors: Simonet Daniel 
Published: October 2007

Abstract

HMOs appeared in the 1970s in a context of increasing health‐care expenditure. These organizations now provide care to an increasing share of the general population, offering cost/effectiveness studies and sophisticated cost‐control mechanisms directed at care providers and patients. The following article reviews the history of Managed Care organizations, details the service they offer, discusses the current difficulties that have forced them to withdraw from some market segments and considers what prompted the government to intervene to protect patients' interests. The paper also describes the growing hostility of patients and physicians to Managed Care.
Copyright © 2007 John Wiley & Sons, Ltd.
But what do they really think? Identifying consumers' values relevant to adopting biotechnologically produced foods
Authors: Grantham Susan 
Published: October 2007

Abstract

Much has been written about the media's importance in the formation of attitudes toward new technologies such as biotechnology. However, little has been published regarding consumer‐held values that play such an important role in forming these attitudes and which ultimately play a role in whether a product is adopted. Understanding how the product will complement, or clash, with, the publics' values is crucial in developing strategic communication plans. Developing Means‐End Chains via Laddering Theory to document users' values has been a useful research method in understanding the attributes and consequences associated with a product that may lead to acceptance by the general public. The purpose of this exploratory research was to identify the values consumers held toward foods created through biotechnological methods and the supporting attributes and consequences that supported those values. The findings indicate that, in this study, consumers felt no differently toward products developed using traditional agricultural methods versus biotechnological methods because the participants overwhelmingly relied on government agencies to ensure that their food was safe. The values identified in this study may provide a common ground for communicating about biotechnologically produced foods.
Copyright © 2007 John Wiley & Sons, Ltd.
Liver expression of proteins controlling interferon‐mediated signalling as predictive factors in the response to therapy in patients with hepatitis C virus infection
Authors: Bautista D , Bermúdez‐Silva FJ , Lasarte JJ , Rodriguez‐Fonseca F , Baixeras E 
Published: October 2007

AbstractCombination therapy with interferon‐alpha (IFNα) and ribavirin is the current treatment of choice for hepatitis C virus (HCV) infection. However, an important number of patients fail to respond to this therapeutic strategy. Factors determining IFN responsiveness are not well understood, and assessment of biomarkers that predict the response to IFN therapy in HCV patients is necessary. Several studies show that particular HCV proteins are able to block IFN function through interaction with important IFN‐signal mediators, such as signal transducers and activators of transcription (STATs). We performed immunostaining analysis of STATs in liver tissue from IFN‐responder vs. non‐responder HCV patients in order to compare the expression profile of these proteins between both groups. Tissue arrays of liver biopsies were used to study the expression of STAT1, STAT2, STAT5 and PIAS1 (protein inhibitor of activated STAT1). Robust and higher expression levels of STAT1, STAT2 and STAT5 in liver tissue from HCV patients were found when compared with samples from healthy donors. However, no significant differences were observed between IFN‐responder and ‐non‐responder groups, but rather increasing levels of STAT1, STAT2 and STAT5 paralleled the degree of liver injury. Importantly, PIAS1 expression in the nucleus of most hepatocytes in HCV tissue biopsy sections, particularly of non‐responder HCV patients, strongly indicated a regulatory effect on STAT1–DNA binding, likely affecting the IFN late signalling. In conclusion, our evidence indicates that intense PIAS1 nuclear staining, widely distributed in hepatocytes of infected livers, could be a good predictive factor of a defective response to IFN treatment, and a biomarker that is easily detectable by immunostaining during standard histopathological liver biopsy analysis. Copyright © 2007 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.