bluuebunny/crossref_metadata_2025_split huggingface dataset:
Alteration in α‐synuclein mRNA expression in Parkinson's disease
Authors: Kingsbury Ann E. , Daniel Susan E. , Sangha Hardev , Eisen Sarah , Lees Andrew J. , Foster Oliver J.F. 
Published: February 2004

AbstractThe presynaptic protein α‐synuclein is considered to play an important role in the pathophysiology of Parkinson's disease (PD). Point mutations in the α‐synuclein gene have been demonstrated in familial PD and α‐synuclein is a major component of Lewy bodies, the pathological hallmark of the sporadic disease. It is not clear whether abnormal accumulation of α‐synuclein is the result of abnormal levels of expression of the gene in neurodegenerative conditions. Expression of α‐synuclein mRNA was therefore studied in control and PD brain using semiquantitative in situ hybridization. α‐synuclein was expressed widely and hybridization signal was seen in most cortical regions, hippocampus, cerebellum, and brain stem. There was little mRNA in the striatum and no hybridization signal was detected in glia. High levels of α‐synuclein mRNA expression in neurons did not seem to be a marker for Lewy body formation. Abundant signal was seen both in regions in which Lewy body deposition occurs commonly in idiopathic PD (PD), such as substantia nigra and frontal and temporal cortex, as well as in less susceptible regions, e.g. visual cortex. Quantitative comparison of mRNA expression in regions of predilection for Lewy body formation showed that mRNA expression was reduced significantly in melanized substantia nigra neurons and frontal cortex neurons in Parkinson's disease. In substantia nigra neurons there seemed to be a negative correlation between cellular mRNA expression and disease duration. These findings are in broad agreement with other studies of the expression of α‐synuclein mRNA in human brain and suggest that Lewy body formation is unlikely to be the result of overexpression of α‐synuclein. © 2003 Movement Disorder Society
Utilization and perceived effectiveness of complementary and alternative medicine in patients with dystonia
Authors: Junker J. , Oberwittler C. , Jackson D. , Berger Klaus 
Published: February 2004

AbstractThe use of complementary and alternative medicine (CAM) is increasing worldwide, especially by patients with chronic diseases. To date, no data are available about utilization and perceived effectiveness of CAM in patients with dystonia. A questionnaire survey on utilization and costs of CAM was completed by 180 members of the German Dystonia Society, a patient advocate group. In total, 131 dystonia patients (73%) were current or former users of CAM, 55 patients used CAM in addition to botulinum toxin A injections, and 86 patients had experience with three or more CAM methods. The options used most widely were acupuncture (56%), relaxation techniques (44%), homeopathy (27%), and massages (26%). Among users of specific CAM methods, breathing therapy, Feldenkrais, massages, and relaxation techniques were perceived as most effective. On average, patients spent
€1,513 on CAM without reimbursement. There was no correlation between costs and perceived effectiveness of different methods. In line with other studies on chronically ill patients, our results show that dystonia patients frequently utilize CAM methods, often in addition to conventional treatment. There is a growing need to evaluate scientifically the effect of CAM methods on symptom severity and quality of life in dystonia, to prevent utilization of costly and ineffective CAM treatments. © 2003 Movement Disorder Society
Anomalies of asymmetry of clinical signs in parkinsonism
Authors: Toth Cory , Rajput Michelle , Rajput Ali H. 
Published: February 2004

AbstractParkinson's disease (PD) is characterized by a minimum of two of three features: tremor, rigidity, and bradykinesia. Asymmetry of these features is often considered to support a diagnosis of PD in contrast to other parkinsonian syndromes. All major manifestations of PD are often more pronounced on the side first manifesting features of PD. Significant dissociation of features on the contralateral side, along with other variants of presentation involving the contralateral side, are rarely observed. To determine the frequency and significance of unusual asymmetry in parkinsonism, we retrospectively examined 613 patients clinically diagnosed as idiopathic PD for presence of unusual asymmetries of clinical features. Three groups of patients with unusual asymmetrical clinical findings were identified. Group 1 comprised 10 patients followed for an average of 6 years presenting with rest tremor most prominent in one lower limb and contralateral upper limb. Group 2 comprised 24 patients followed for an average of 5.5 years with action tremor most prominent on the side contralateral to the side of most prominent rest tremor. Group 3 comprised 33 patients followed for an average of 10 years who had parkinsonian signs of greatest severity on one side but subsequently, over an average of 5.4 years, became gradually more prominent on the opposite side. In Group 3, 15 of 33 patients (45%) demonstrated evolution to a rigid form of parkinsonism with disappearance of rest tremor over an average of 7.1 years after presentation. A small percentage (11%) of Parkinson's patients in our clinic demonstrated anomalous asymmetrical clinical findings, which indicates that (1) the disease process may begin in different topographic sites on each side; (2) rest tremor and action tremor may have different anatomical bases; (3) the disease process may progress at different rates on different sides; and (4) tremor becomes less pronounced with progression of disease in some patients with Parkinsonism. © 2003 Movement Disorder Society
An immersed finite element space and its approximation capability
Authors: Li Z. , Lin T. , Lin Y. , Rogers R. C. 
Published: February 2004

AbstractThis article discusses an immersed finite element (IFE) space introduced for solving a second‐order elliptic boundary value problem with discontinuous coefficients (interface problem). The IFE space is nonconforming and its partition can be independent of the interface. The error estimates for the interpolation of a function in the usual Sobolev space indicate that this IFE space has an approximation capability similar to that of the standard conforming linear finite element space based on body‐fit partitions. Numerical examples of the related finite element method based on this IFE space are provided. © 2004 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq 20: 338–367, 2004
Application of a Mickens finite‐difference scheme to the cylindrical Bratu‐Gelfand problem
Authors: Buckmire Ron 
Published: February 2004

AbstractThe boundary value problem Δu + λeu = 0 where u = 0 on the boundary is often referred to as “the Bratu problem.” The Bratu problem with cylindrical radial operators, also known as the cylindrical Bratu‐Gelfand problem, is considered here. It is a nonlinear eigenvalue problem with two known bifurcated solutions for λ < λc, no solutions for λ > λc and a unique solution when λ = λc. Numerical solutions to the Bratu‐Gelfand problem at the critical value of λc = 2 are computed using nonstandard finite‐difference schemes known as Mickens finite differences. Comparison of numerical results obtained by solving the Bratu‐Gelfand problem using a Mickens discretization with results obtained using standard finite differences for λ < 2 are given, which illustrate the superiority of the nonstandard scheme. © 2004 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq 20: 327–337, 2004
Mechanisms of Calcium Elevation in the Micromeres of Sea Urchin Embryos
Authors: Yazaki Ikuko , Abe Michio , Santella Luigia , Koyama Yumiko 
Published: February 2004

Abstract The micromeres, the first cells to be specified in sea urchin embryos, are generated by unequal cleavage at the fourth cell division. The micromeres differentiate autonomously to form spicules and dispatch signals to induce endomesoderm in the neighbouring macromeres cells in the embryo. Using a calcium indicator Fura‐2/AM and a mixture of dextran conjugated Oregon green‐BAPTA 488 and Rhodamine red, the intracellular calcium ion concentration ([Ca2+]i) was studied in embryos at the 16‐cell stage. [Ca2+]i was characteristically elevated in the micromeres during furrowing at the 4th cleavage. Subsequently, Ca2+oscillated for about 10 min in the micromeres, resulting in episodic high levels of [Ca2+]i. High [Ca2+]i regions were associated with regional localizations of the endoplasmic reticulum (ER), though not with ER accumulated at the vegetal pole of the micromeres during the 4th division. Pharmacological studies, using a blocker of IP3‐mediated Ca2+ release (Xestospongin), a store‐operated Ca2+ entry inhibitor (2 aminoethoxydiphenyl borate (2‐APB)) and an inhibitor of stretch‐dependent ion channels (gadolinium), suggest that the high [Ca2+]i and oscillations in the micromeres are triggered by calcium influx caused by the activation of stretch‐dependent calcium channels, followed by the release of calcium ions from the endoplasmic reticulum. On the basis of these new findings, a possible mechanism for autonomous formation of the micromeres is discussed.
In vivo kinematics of mobile‐bearing knee arthroplasty in deep knee bending motion
Authors: Watanabe Tetsu , Yamazaki Takaharu , Sugamoto Kazuomi , Tomita Tetsuya , Hashimoto Hideo , Maeda Daisuke , Tamura Shinichi , Ochi Takahiro , Yoshikawa Hideki 
Published: February 2004

AbstractThe current study aimed to analyze kinematics during deep knee bending motion by subjects with fully congruent mobile‐bearing total knee arthroplasties allowing axial rotation and anteroposterior (AP) gliding. Twelve subjects were implanted with Dual Bearing Knee prostheses (DBK, slot type: Finsbury Orthopaedics, Surrey, UK). These implants include a mobile‐bearing insert that is fully congruent with the femoral component throughout flexion and allows axial rotation and limited AP translation. Sequential fluoroscopic images were taken in the sagittal plane during loaded knee bending motion. In vivo kinematics were analyzed using a two‐ to three‐dimensional registration technique, which uses computer‐assisted design models to reproduce the spatial position of femoral and tibial components from single‐view fluoroscopic images. The average femoral component demonstrated 13.4° external axial rotation for 0–120° flexion. On average, the medial condyle moved anteriorly 6.2 mm for 0–100° flexion, then posteriorly 4.0 mm for 100–120° flexion. On average, the lateral condyle moved anteriorly 1.0 mm for 0–40° flexion, then posteriorly 8.7 mm for 40–120° flexion. The typical subject exhibited a lateral pivot pattern from extension to 60° flexion and a central pivot pattern from 60° to 100° flexion, patterns that are not usually observed in normal knees. Subsequently from 100° to 120° flexion, a rollback pattern was reproduced in which bilateral condyles moved backward. © 2004 Orthopaedic Research Society. Published by Elsevier Ltd. All rights reserved.
The ‘Mental State’ Theory of Intentions
Authors: Scheer Richard 
Published: February 2004

This theory regards intentions as mental states, e.g., attitudes, which, typically, have causal power. But we do not speak of our intentions as having such powers. Instead, we speak of a person's resolve, determination, or his anxiety, eagerness, and so forth, as the ‘powers’ that move us. Of course, one desires for various reasons to carry out his various intentions but that desire is not a component of the intentions. An intention is, roughly, the course of action that one has adopted, so it has no such components.There are other characteristics of intentions which the mental state idea of intentions does not share. Intentions do not have the temporal characteristics that mental states have, or share the curious context dependency that intentions have. And since, according to the theory, mental states operate causally, it would not be possible for a person to commit himself to a course of action as we ordinarily do when we make a promise or sign an agreement or contract.
Error in shear‐wave polarization and time splitting
Authors: Michaud Gwénola , Snieder Roel 
Published: February 2004

ABSTRACTShear‐wave polarization and time delay are attributes commonly used for fracture detection and characterization. In time‐lapse analysis these parameters can be used as indicators of changes in the fracture orientation and density. Indeed, changes in fracture characteristics provide key information for increased reservoir characterization and exploitation. However, relative to the data uncertainty, is the comparison of these parameters over time statistically meaningful? We present the uncertainty in shear‐wave polarization and time delay as a function of acquisition uncertainties, such as receiver and source misorientation, miscoupling and band‐limited random noise. This study is applied to a time‐lapse borehole seismic survey, recorded in Vacuum Field, New Mexico. From the estimated uncertainties for each survey, the uncertainty in the difference between the two surveys is 31° for the shear‐wave polarization angle and 4 ms for the shear‐wave time delay. Any changes in these parameters greater than these error estimates can be interpreted with confidence. This analysis can be applied to any time‐lapse measurement to provide an interval of confidence in the interpretation of shear‐wave polarization angles and time splitting.
Effect of grain scale alignment on seismic anisotropy and reflectivity of shales
Authors: Arne Johansen Tor , Ole Ruud Bent , Jakobsen Morten 
Published: February 2004

ABSTRACTThe elastic properties and anisotropy of shales are strongly influenced by the degree of alignment of the grain scale texture. In general, an orientation distribution function (ODF) can be used to describe this alignment, which, in practice, can be characterized by two Legendre coefficients. We discuss various statistical ODFs that define the alignment by spreading from a mean value; in particular, the Gaussian, Fisher and Bingham distributions. We compare the statistical models with an ODF resulting from pure vertical compaction (no shear strain) of a sediment. The compaction ODF may be used to estimate how the elastic properties and anisotropy evolve due to burial of clayey sediments.Our study shows that the three statistical ODFs produce almost identical correspondence between the two Legendre coefficients as a function of the spreading parameter, so that the spreading parameter of one ODF can be converted to the spreading parameter of another ODF. In most cases it is then sufficient to apply the spreading parameter for the ODF instead of the two Legendre coefficients. The effect of compaction on the ODF gives a slightly different correspondence between the two Legendre coefficients from that for the other models. In principle, this opens up the possibility of distinguishing anisotropy effects due to compaction from those due to other processes.We also study reflection amplitudes versus angle of incidence (AVA) for all wave modes, where shales having various ODFs overlie an isotropic medium. The AVA responses are modelled using both exact and approximation formulae, and their intercepts and gradients are compared. The modelling shows that the S‐wave velocity is sensitive to any perturbation in the spreading parameter, while the P‐wave velocity becomes increasingly sensitive to a perturbation of a less ordered system. Similar observations are found for the AVA of the P‐P and P‐SV waves. Modelling indicates that a combined use of the amplitude versus offset of P‐P and P‐SV reflected waves may reveal certain grain scale alignment properties of shale‐like rocks.
A comparison of receiver technologies in borehole MMR and EM surveys
Authors: Elders J.A. , Asten M.W. 
Published: February 2004

ABSTRACTA series of downhole magnetometric resistivity (DHMMR) and downhole electromagnetic (DHEM) surveys were conducted near Broken Hill, New South Wales, Australia, and at Zinkgruvan, Sweden, to determine how probe and receiver equipment choices affect the amount of noise visible in borehole MMR and EM data. Noise analyses performed on the data, using the standard deviation to gauge the relative noise levels between different probes and receiver systems, indicate that high noise levels in MMR data result primarily from the use of a three‐component EM probe, which has a reduced effective area and hence a higher noise floor compared with a single‐component EM probe. High noise, attributable to cultural sources such as nearby power lines, in either MMR or EM data can be reduced through the use of full‐waveform, multipurpose receiver systems. These systems allow for the use of tapered stacking, which is a more effective method of eliminating coherent noise associated with power‐line transients than the boxcar‐stacking method used by traditional receiver systems.
Comparison of the virulence of Armillaria cepistipes and Armillaria ostoyae on four Norway spruce provenances
Authors: Prospero S. , Holdenrieder O. , Rigling D. 
Published: February 2004

SummaryThe basidiomycetes Armillaria cepistipes and Armillaria ostoyae frequently occur in the same forest stand. In this study, we determined the virulence of 20 isolates of A. cepistipes and 16 isolates of A. ostoyae on four different provenances of 2‐year‐old Norway spruce (Picea abies). Within 30 months after inoculation, 1.1 and 19.1% of the seedlings inoculated with A. cepistipes and A. ostoyae, respectively, had died or were dying. The incidence of dead and dying seedlings varied between 3 and 49% among the A. ostoyae isolates. The virulence of an isolate was positively correlated to its ability to produce rhizomorphs. One Norway spruce provenance showed significantly lower susceptibility to A. ostoyae than the other three. Rhizomorphs of both Armillaria species were attached to the root surface. The attached rhizomorphs of A. ostoyae, however, were associated with significantly more lesions. The virulence of the isolates was not correlated with their wood‐degrading capability for either of the Armillaria species.
Sphaceloma murrayae Jenk. & Grods., a pathogen new to Europe on Salix spp.
Authors: Butin H. , Kehr R. 
Published: February 2004

SummaryA Sphaceloma species causing greyish‐white leaf spots of several Salix species is described and illustrated. This is the first record for Europe of the mitosporic fungus identified as Sphaceloma murrayae, which was formerly known to occur only in New Zealand, Argentina and the US. In addition to information on symptoms and hosts, similar fungi occurring on willow, which can be confused with the new fungus are also discussed.
Rhizomorph growth habit, saprophytic ability and virulence of 15 Armillaria species
Authors: Morrison D. J. 
Published: February 2004

SummaryThe rhizomorph branching habit in soil, competitive saprophytic ability and virulence were determined for 15 species of Armillaria from Europe, North America and Australia and New Zealand. In soil, rhizomorphs of northern hemisphere species branched either monopodially or dichotomously, whereas all five species from Australia and New Zealand branched dichotomously. The dry weight of rhizomorphs produced in soil by isolates of a species and by species was very variable. Species with monopodially branched rhizomorphs had significantly higher saprophytic colonization scores than dichotomously branched species and scores were significantly higher in Garry oak than Douglas‐fir segments and in fresh than autoclaved segments. The damage to Douglas‐fir seedlings caused by isolates of most dichotomously branched species was significantly greater than that caused by monopodially branched species. Species producing dichotomously branched rhizomorphs were more aggressive than monopodially branched species, killing 80% (vs. 17%) of seedlings that died during the first year of the 2‐year experiment.
Effects of hot water treatment, biocontrol agents, disinfectants and a fungicide on storability of English oak acorns and control of the pathogen,Ciboria batschiana
Authors: Knudsen I. M. B. , Thomsen K. A. , Jensen B. , Poulsen K. M. 
Published: February 2004

SummaryEight biological control agents (BCAs;Clonostachys rosea,Trichoderma harzianum,Trichoderma polysporum,Phlebiopsis gigantea,Bacillus subtilis,Pseudomonas chlororaphis,Streptomyces griseoviridis), five disinfectants and a fungicide (Prochloras‐ManganTM) were evaluated for the control of harmful mycoflora onCiboria batschiana‐infected English oak (Quercus robur) acorns during storage at −1°C. All treatments were tested on both hot water‐treated (HW) and untreated acorns. HW‐treated acorns generally stored better than untreated acorns as a result of elimination ofC. batschiana. The HW treatment increased the germination percentage before storage from 60 to 85%. Germination of HW‐treated acorns decreased from 85 to 40% after 16.5 months of storage, whereas germination of untreated acorns decreased from 60 to 20% after a similar time.Ciboria batschianainfection of untreated acorns increased from 14% before storage to 55% after 16 months of storage. All disinfectants and BCAs had a positive effect on viability and particularly on control ofC. batschianain untreated acorns. Best control ofC. batschianaoccurred withC. rosea, MycostopTM(S. griseoviridis), Binab TFTM(T. polysporum + T. harzianum), andP. chlororaphis. For HW‐treated acorns, there was only a small effect of BCAs on acorn viability while the fungicide and the disinfectants had no effect. Treatments also affected the saprophytic mycoflora with the HW treatment reducing the frequency ofCladosporiumspp. andPapulasporaspp., but enhancingAlternariaspp.,MucoraceaeandPenicilliumspp. However, when combined with HW treatment, several BCAs significantly reduced the prevalence of these fungi. Also,C. roseareduced the growth ofFusariumspp. Significant negative correlations (p < 0.001) were found between acorn germination and certain storage fungi such asAcremoniella atra,Cladosporiumspp. and dematiaceous mycelia.
Intraneuronal amyloid‐β1‐42 production triggered by sustained increase of cytosolic calcium concentration induces neuronal death
Authors: Pierrot Nathalie , Ghisdal Philippe , Caumont Anne‐Sophie , Octave Jean‐Noël 
Published: February 2004

AbstractAlzheimer's disease (AD) is a neurodegenerative disorder characterized by the presence in the brain of senile plaques which contain an amyloid core made of β‐amyloid peptide (Aβ). Aβ is produced by the cleavage of the amyloid precursor protein (APP). Since impairment of neuronal calcium signalling has been causally implicated in ageing and AD, we have investigated the influence of an influx of extracellular calcium on the metabolism of human APP in rat cortical neurones. We report that a high cytosolic calcium concentration, induced by neuronal depolarization, inhibits the α‐secretase cleavage of APP and triggers the accumulation of intraneuronal C‐terminal fragments produced by the β‐cleavage of the protein (CTFβ). Increase in cytosolic calcium concentration specifically induces the production of large amounts of intraneuronal Aβ1‐42, which is inhibited by nimodipine, a specific antagonist of l‐type calcium channels. Moreover, calcium release from endoplasmic reticulum is not sufficient to induce the production of intraneuronal Aβ, which requires influx of extracellular calcium mediated by the capacitative calcium entry mechanism. Therefore, a sustained high concentration of cytosolic calcium is needed to induce the production of intraneuronal Aβ1‐42 from human APP. Our results show that this accumulation of intraneuronal Aβ1‐42 induces neuronal death, which is prevented by a functional γ‐secretase inhibitor.