bluuebunny/crossref_metadata_2025 huggingface dataset:
Effects of a startle on heart rate in patients with multiple system atrophy
Authors: Valls‐Solé Josep , Veciana Misericordia , Leon Lucia , Valldeoriola Francesc
Published: October 2002

The patient cooperation usually required for neurophysiological assessment of autonomic cardioregulatory function is difficult to obtain from patients with bradykinesia. A particularly interesting condition occurs in multiple system atrophy (MSA), which features both bradykinesia and autonomic dysfunction. Another characteristic of patients with MSA is their normal motor reaction to a startling stimulus. We used startle as a stimulus for testing autonomic cardioregulatory function in patients with MSA, thus avoiding the need for patient cooperation. In 10 healthy volunteers and 8 MSA patients, we recorded the electrocardiographic QRS complex with surface electrodes attached over the chest and delivered an acoustic startle stimulus after 8 seconds of baseline recording. We calculated the ratio between the pre‐stimulus and the post‐stimulus heart beat intervals (R–R ratio) by dividing the mean prestimulus R–R interval by the shortest R–R interval obtained within 10 seconds poststimulus. Healthy volunteers had a significant shortening of the R–R interval. The peak of the effect occurred after 2 to 5 seconds, with a mean R–R ratio of 1.14 (S.D. = 0.09). In contrast, R–R shortening was markedly reduced in patients, even though they had a normal motor response. The mean R–R ratio in patients was 1.03 (S.D. = 0.03), significantly lower than in healthy volunteers (P < 0.01). Our results demonstrate an abnormally reduced modulation of the heart beat frequency in patients with MSA, compatible with a dysfunction on pathways responsible for autonomic regulation. The method described here may be useful in the assessment of cardioregulatory function in poorly cooperative patients with normal startle responses. © 2002 Movement Disorder Society
Health‐Related quality of life in patients with advanced Parkinson's disease treated with deep brain stimulation of the subthalamic nuclei
Authors: Just Helle , Ostergaard Karen
Published: October 2002

Parkinson's disease (PD) is a progressive neurodegenerative disorder for which there is as yet no cure. It affects many aspects of patients' lives, only some of which can be monitored by available clinical rating scales. In the past decade, there has been a new emphasis on the use of health‐related quality of life (HRQOL) measures to describe patient response to treatment. We describe patient‐reported HRQOL in subjects who underwent bilateral deep brain stimulation (DBS) of the subthalamic nuclei (STN) for the treatment of PD, compared with a similar group of subjects who did not receive surgical treatment. A consecutive series of patients (n = 11) with advanced idiopathic PD were treated with DBS of the STN. This surgically treated group was compared prospectively with a similar group of patients (n =13) awaiting surgery. Self‐reported HRQOL, measured by the Parkinson's Disease Questionnaire (PDQ‐39) was evaluated at three time periods T0, T3, and T6. The surgery group was evaluated according to the Unified Parkinson's Disease Rating Sale (UPDRS) before (T0), 3 (T3), and 6 months (T6) after surgery. HRQOL, UPDRS part II and III, duration of off periods, and dyskinesias improved significantly from T0 to T3 and from T0 to T6 for the surgery group but not for the nonsurgery group. Ten of the 11 patients treated with DBS of the STN reported a lower summary score (indicating better HRQOL) 6 months after surgery. The results of this prospective controlled study suggest that patients with advanced idiopathic PD treated with DBS of the STN obtain significant improvements in patient reported HRQOL and in clinical outcomes 3 and 6 months after surgery. © 2002 Movement Disorder Society
Friedreich's ataxia with chorea and myoclonus caused by a compound heterozygosity for a novel deletion and the trinucleotide GAA expansion
Authors: Zhu Danqing , Burke Christopher , Leslie Anthony , Nicholson Garth A.
Published: October 2002

Friedreich's ataxia (FRDA) is the most common hereditary ataxia, affecting about 1 in 50,000 individuals. It is caused by mutations in the frataxin gene; 98% of cases have homozygous expansions of a GAA trinucleotide in intron 1 of the frataxin gene. The remaining 2% of patients are compound heterozygotes, who have a GAA repeat expansion in one allele and a point mutation in the other allele. FRDA patients with point mutation have been suggested to have atypical clinical features. We present a case of compound heterozygotes in a FRDA patient who has a deletion of one T in the start codon (ATG) of the frataxin gene and a GAA repeat expansion in the other allele. The patient presented with chorea and subsequently developed FRDA symptoms. The disease in this case is the result of both a failure of initiation of translation and the effect of the expansion. This novel mutation extends the range of point mutations seen in FRDA patients, and also broadens the spectrum of FRDA genotype associated with chorea. © 2002 Movement Disorder Society
Prevalence of stroke in Parkinson's disease: A postmortem study
Authors: Mastaglia Frank L. , Johnsen Russell D. , Kakulas Byron A.
Published: October 2002

The results of previous epidemiological studies of the relationship between Parkinson's disease and stroke have been conflicting; some showing a reduced risk of ischaemic and haemorrhagic stroke during life, and others indicating an increased likelihood of stroke‐related death. We compared the frequency of cerebral infarcts and haemorrhages at postmortem in 100 cases of pathologically verified idiopathic Parkinson's disease and 100 age‐matched control brains. No significant differences were found in the numbers of infarcts or haemorrhages or stroke‐related deaths between the two groups. Our findings do not indicate either a protective effect against stroke, or a greater susceptibility to death from stroke, in the population studied. © 2002 Movement Disorder Society
Lower limb replantations: Indications and a new scoring system
Authors: Battiston Bruno , Tos Pierluigi , Pontini Italo , Ferrero Sebastiano
Published: October 2002

The need for reconstruction of lower limb amputations is increasing, due to high‐energy trauma in road accidents and work‐related injuries. The indication for lower limb replantation is still controversial. Compared with upper limb replantations, indications are more select due to the frequent complications in lower limb salvage procedures, such as severe general complications or local complications such as necrosis, infections, nonunions, the need for secondary lengthening, or other reconstructive procedures. The satisfactory results given by artificial prosthesis, such as quicker recovery time and fewer secondary procedures, also contribute to the higher degree of selection for lower limb replantation candidates. Since 1993, we have replanted 14 amputations of the lower limb in 12 patients, including 2 bilateral cases. Although survival of the replanted segment was obtained in all patients, 5 cases were subsequently amputated for severe secondary complications. Of the remaining 9 cases, evaluated by means of Chen criteria, 7 had good results (3 Chen I and 4 Chen II), 1 sufficient (Chen III), and 1 poor (Chen IV). The best results were obtained in young patients. Our experience led us to examine the necessity for careful, objective patient selection. We developed a score evaluation system by modifying the international classifying method for severe limb traumas (mangled extremity severity score, or MESS system). This relatively simple system, based on the retrospective study of our cases, considers several parameters (patient's age, general conditions, level and type of lesion, time of injury, and associated lesions), giving each one a score. The total score gives the indication for replantation, predicts the functional outcome, and facilitates decision‐making. © 2002 Wiley Liss, Inc. MICROSURGERY 22:187–192 2002
Tilted beam slot loop antenna
Authors: Subbarao B. , Fusco V. F.
Published: October 2002

This Letter describes a slot loop antenna that is partially short circuited in order to create beam tilt in the far‐field radiation for the purpose of reduced SAR. Here the characteristics of a partly shorted slot loop constructed on low‐dielectric‐constant PCB material, εr = 2.33 designed to operate at 2400 MHz are illustrated. The loop is fed from a microstrip line, removing the requirement for the balun feed arrangement normally required for loop antennas. The resulting antenna exhibits a 30° beam tilt and has an estimated gain of 6 dBi. © 2002 Wiley Periodicals, Inc. Microwave Opt Technol Lett 34: 332–333, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.10453
Parasitic suppression in high‐Q‐factor dielectric loaded cavity filters
Authors: Simeoni Massimiliano , Verdeyme Serge , Guillon Pierre , Sorrentino Roberto
Published: October 2002

A principle to suppress parasitic transmission peak occurrence in high‐Q‐factor dielectric‐loaded cavity filters is presented in this Letter. As an example a two–pole filter, using an original structure, is presented and realized. Experimental results fully confirm the predicted behavior of the cavity. © 2002 Wiley Periodicals, Inc. Microwave Opt Technol Lett 34: 344–347, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.10458
On the calculation of safety distances for human exposure to electromagnetic fields from base‐station antennas
Authors: Martínez‐Búrdalo M. , Nonídez L. , Martín A. , Villar R.
Published: October 2002

The validity of simple formulas based on cylindrical and far‐field approximation models for calculating minimum safety distances for the assessment of human exposure to electromagnetic fields from base station antennas is analyzed by comparing with FDTD computations. Results for different actual antenna models show the suitability of each formulation. © 2002 Wiley Periodicals, Inc. Microwave Opt Technol Lett 34: 364–367, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.10463
CAD model analysis of the air‐gap type TFBAR
Authors: Kim Kun‐Wook , Yook Jong‐Gwan , Park Han‐Kyu
Published: October 2002

A CAD model for an air‐gap‐type TFBAR is presented. Aluminum nitride is used as the piezoelectric material with platinum electrodes. To verify the model, simulated and measured results are compared for various top electrode thicknesses, and the agreement is within 0.5% for the parallel resonance frequency. © 2002 Wiley Periodicals, Inc. Microwave Opt Technol Lett 34: 384–385, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.10469
A CPWG‐fed dual‐frequency rectangular patch antenna
Authors: Chen Jin‐Sen
Published: October 2002

Design of a rectangular coplanar patch antenna for obtaining dual‐frequency operation using a coplanar waveguide with ground (CPWG) feed is presented. This is achieved by introducing an CPWG feed line attaching on the diagonal of the patch. Details of the proposed designs are described, and experimental and theoretical results are presented and discussed. © 2002 Wiley Periodicals, Inc. Microwave Opt Technol Lett 34: 397–398, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.10473
17O, 13C and 1H NMR and IR spectral study of crowded ketones: possible intramolecular C—H···O interactions
Authors: Qin Xu‐rong , Ishizuka Yasuko , Lomas John S. , Tezuka Takahiro , Nakanishi Hiroshi
Published: October 2002

Unusual behaviour was observed in the study of the 17O, 13C and 1H NMR and IR spectra of crowded (1‐adamantyl)alkyl ketones. As the size of the alkyl substituent is increased, abnormal upfield chemical shifts in the 13C NMR and downfield shifts in the 17O NMR of the carbonyl group, as well as downfield shifts in the 1H NMR of the adamantyl γ'‐protons, are found. In the IR spectrum, the νCO stretching frequencies of the ketones with bulky substituents show considerable red shifts. Correlation of the NMR shifts with the number of γ‐carbon atoms of the alkyl substituents and comparison with the IR results indicated that there is an intramolecular through‐space CH···O interaction in crowded ketones. This was supported by the results of ab initio calculations. Copyright © 2002 John Wiley & Sons, Ltd.
The phenotypic consequences of MECP2 mutations extend beyond rett syndrome
Authors: Hammer Sara , Dorrani Naghmeh , Dragich Joanna , Kudo Shinichi , Schanen Carolyn
Published: October 2002

Although MECP2 was initially identified as the causative gene in classic Rett syndrome (RTT), the gene has now been implicated in several phenotypes that extend well beyond the clinically defined disorder. MECP2 mutations have been found in people with various disorders, including neonatal onset encephalopathy, X‐linked recessive mental retardation (MRX), classic and atypical RTT, autism, and Angelman syndrome, as well as mildly affected females and normal carrier females. To make matters more complex, in approximately 20% of classic sporadic RTT cases and more than 50% of affected sister pairs, no mutation in MECP2 has been found. X‐chromosome inactivation patterns can clearly affect the phenotypic expression in females, while the effect of the type and position of the mutation is more apparent in the broader phenotype than in RTT. Both males and females are at risk, although an excess of paternally derived mutations are found in most cases of classic RTT. Thus, because of the range of disparate phenotypes, the gene may account for a relatively large portion of mental retardation in the population. MRDD Research Reviews 2002;8:94–98. © 2002 Wiley‐Liss, Inc.
Direct reconstruction of MR images from data acquired on a non‐Cartesian grid using an equal‐phase‐line algorithm
Authors: Qian Yongxian , Lin Jiarui , Jin Deqin
Published: October 2002

The equal‐phase line (EPL) algorithm is proposed as a means of allowing rapid Fourier transform (FT) reconstruction of MR image data acquired on a non‐Cartesian grid. The pixels on the image are grouped according to their positions. The pixels in a group have the same phase in the complex exponential function −exp[j2π(xu + yv)] and receive the same contribution from a data point. Each group is related to an EPL in the image space. The contribution of a data point can then be distributed to the pixels along the EPLs. The described EPL algorithm enables a decrease of the reconstruction time to about 40% of the direct FT (DrFT) for the non‐Cartesian data. A numerical phantom and two sets of in vivo spiral data were used to investigate an optimal number of the EPLs and to measure the reconstruction time. The EPL algorithm runs nearly as fast as the look‐up table (LUT) method (Dale et al. IEEE Trans Med Imaging 2001;20:207–217), but it does not require a large memory to store the coefficients in advance, as is required in the LUT method. Thus, the EPL algorithm can be used to reconstruct images up to 512 × 512 pixels in size in a PC of limited memory, and may be more conveniently applied to a multiprocessor system. Magn Reson Med 47:1228–1233, 2002. © 2002 Wiley‐Liss, Inc.
Perfusion quantification using Gaussian process deconvolution
Authors: Andersen I.K. , Szymkowiak A. , Rasmussen C.E. , Hanson L.G. , Marstrand J.R. , Larsson H.B.W. , Hansen L.K.
Published: October 2002

The quantification of perfusion using dynamic susceptibility contrast MRI (DSC‐MRI) requires deconvolution to obtain the residual impulse response function (IRF). In this work, a method using the Gaussian process for deconvolution (GPD) is proposed. The fact that the IRF is smooth is incorporated as a constraint in the method. The GPD method, which automatically estimates the noise level in each voxel, has the advantage that model parameters are optimized automatically. The GPD is compared to singular value decomposition (SVD) using a common threshold for the singular values, and to SVD using a threshold optimized according to the noise level in each voxel. The comparison is carried out using artificial data as well as data from healthy volunteers. It is shown that GPD is comparable to SVD with a variable optimized threshold when determining the maximum of the IRF, which is directly related to the perfusion. GPD provides a better estimate of the entire IRF. As the signal‐to‐noise ratio (SNR) increases or the time resolution of the measurements increases, GPD is shown to be superior to SVD. This is also found for large distribution volumes. Magn Reson Med 48:351–361, 2002. © 2002 Wiley‐Liss, Inc.
Motor unit activation order during electrically evoked contractions of paralyzed or partially paralyzed muscles
Authors: Thomas Christine K. , Nelson Gary , Than Lara , Zijdewind Inge
Published: October 2002

The activation order of motor units during electrically evoked contractions of paralyzed or partially paralyzed thenar muscles was determined in seven subjects with chronic cervical spinal cord injury. The median nerve was stimulated percutaneously with pulses of graded intensity to produce increments in the compound electromyogram (EMG) and force. Each increment corresponded to the activation of another unit. The evoked unit EMG and force was obtained by digital subtraction. The thenar muscles had between 15 and 83 units (26 ± 19) that produced 114.3 ± 127.1 mN force (n = 290). In six subjects, a significant positive correlation was found between activation order and unit force indicating that weaker units were excited before stronger units. These data are contrary to the notion that a reversal of unit activation order occurs during evoked versus voluntary contractions. © 2002 Wiley Periodicals, Inc. Muscle Nerve 25: 000–000, 2002
Relative distribution of three major lactate transporters in frozen human tissues and their localization in unfixed skeletal muscle
Authors: Fishbein William N. , Merezhinskaya Natalya , Foellmer John W.
Published: October 2002

We have prepared affinity‐purified rabbit polyclonal antibodies to the near‐C‐terminal peptides of human monocarboxylate transporters (MCTs) 1, 2, and 4 coupled to keyhole limpet hemocyanin. Each antiserum reacted only with its specific peptide antigen and gave a distinct molecular weight band (blocked by preincubation with antigen) after chemiluminescence reaction on Western blots from sodium dodecyl sulfate–polyacrylamide gel electrophoresis (SDS‐PAGE) of tissue membrane proteins. Densitometry showed distinctive expression patterns for each MCT in a panel of 15 frozen human tissues, with the distribution of MCT1 ≫L:MCT2>MCT4. Fluorescence microscopy of unfixed skeletal muscle using fluorescein‐conjugated secondary antibody was correlated with reverse adenosine triphosphatase (ATPase) stained sequential sections to identify fiber‐type localization. MCT1 expression was high in the sarcolemma of type 1 fibers, modest to low in type 2a fibers, and almost absent in type 2b fibers. In contrast, MCT4 expression was low to absent in the membrane of most type 1 fibers, but high in most 2a and in all 2b fibers, favoring the view that their high lactate levels during work may be channeled in part to neighboring type 1 (and perhaps 2a) fibers for oxidation, thereby delaying fatigue. MCT2 expression was limited to the sarcolemma of a type 1 fiber subset, which varied from <5 to 40%, depending on the specific muscle under study. Quantitative chemiluminescent densitometry of 10 muscle biopsies for their MCT2 and MCT4 content, each normalized to MCT1, confirmed the unique variation of MCT2 expression with biopsy site. The application of these antibodies should add to the understanding of motor unit physiology, and may contribute to the muscle‐biopsy assessment of low‐level denervation. © 2002 Wiley Periodicals, Inc. Muscle Nerve 26: 101–112, 2002
Effect of sympathetic muscle vasoconstrictor activity on capsaicin‐induced muscle pain
Authors: Wasner Gunnar , Bréchôt Alexander , Schattschneider Jörn , Allardt Arne , Binder Andreas , Jensen Troels S. , Baron Ralf
Published: October 2002

Neuropathic pain syndromes with sympathetically maintained pain are often associated with a deep somatic pain component. An adrenergic interaction between sympathetic vasoconstrictor neurons and cutaneous afferents has been demonstrated. To determine whether a sympathetic–afferent interaction exists in deep somatic tissues, we investigated the effect of sympathetic muscle vasoconstrictor activity on experimentally induced pain. In 12 healthy volunteers, capsaicin was infused into the anterior tibial muscle. Intensity and quality of muscle and referred pain were assessed. The analyses were performed during the presence of low sympathetic muscle vasoconstrictor activity induced by breathing 100% O2 gas (normocapnia), and during high activity induced by inspiration of 95% O2 and 5% CO2 (hypercapnia). The degree of sympathetic muscle vasoconstrictor discharge was monitored indirectly by measuring systemic blood pressure and end‐expiratory CO2 and by performing duplex sonography of muscle resistance vessels. The intensity, quality, and spatial distribution of muscle and referred pain were not significantly different during resting and increased sympathetic muscle vasoconstrictor discharge, indicating that such activity does not influence pain after intramuscular infusion of capsaicin. © 2002 Wiley Periodicals, Inc. Muscle Nerve 26: 113–121, 2002
Interactions between endogenous nitric oxide and hypoxemia in activation of group IV muscle afferents
Authors: Arbogast Sandrine , Darques Jean Luc , Jammes Yves
Published: October 2002

It has previously been shown that both hypoxemia and nitric oxide (NO) synthase blockade depress the activation of group IV muscle afferents after muscle stimulation (MS). In the present study, we questioned whether hypoxemia exerts a specific inhibitory influence, independently from its effects on endogenous NO formation. This hypothesis was tested in two groups of anesthetized rabbits in which we examined the effects of hypoxemia, and then of subsequent NO synthase blockade by NG‐nitro‐L‐arginine methyl ester (L‐NAME), and vice versa. In each protocol, group IV afferent activity was recorded from the resting tibialis anterior muscle and after 3‐min periods of MS that elicited a significant decrease in muscle force. NO synthase blockade in normoxemia suppressed the group IV afferent response to MS, and hypoxemia alone significantly reduced the post‐MS activation of these nerve afferents (+18% vs. +28% in normoxemia). In hypoxemic rabbits, further NO synthase blockade abolished the post‐MS activation of group IV afferents. Moreover, when hypoxemia followed the NO synthase blockade, MS significantly reduced the discharge of group IV afferents (−28%). Thus, while these muscle afferents are activated after fatiguing muscle contractions when the endogenous NO production is present, they are deactivated by hypoxemia when NO production is blocked. We conclude that endogenous NO production and hypoxemia exert opposite effects on the activation of the group IV afferents. Our data anticipate the neuromuscular side effects of treatments using exogenous NO or drugs acting on endogenous NO production. © 2002 Wiley Periodicals, Inc. Muscle Nerve 26: 194–200, 2002
An augmented Lagrangian approach to essential boundary conditions in meshless methods
Authors: Ventura G.
Published: October 2002

The problem of boundary conditions enforcement in meshless methods has been solved in the literature by several approaches. In the present paper, the moving least‐squares (MLS) approximation is introduced in the total potential energy functional for the elastic solid problem and an augmented Lagrangian term is added to satisfy essential boundary conditions. The method can be easily extended to any kind of constraint for the approximation variables. The solution is found by iterating alternatively on approximation variables and on Lagrange multipliers. The advantages of the proposed formulation are: (a) the ability to deal with the same approach with any constraint type; (b) the number of the variables is not increased by the Lagrange multipliers; (c) the Hessian of the functional w.r.t. the approximation variables is banded, well conditioned and strictly positive definite and (d) the cost of the augmented Lagrangian iteration is a very small fraction of the global computing time. Therefore, the augmented Lagrangian element‐free (ALEF) approach represents an attractive and very efficient numerical tool, not only for the boundary conditions enforcement, but also for the solution of interface and non‐linear problems. Copyright © 2001 John Wiley & Sons, Ltd.
On configurational forces in the context of the finite element method
Authors: Mueller R. , Kolling S. , Gross D.
Published: October 2002

The theory of configurational forces is briefly recast, together with the underlying balance laws. It is shown, that in the case of a homogeneous body without body forces the additional balance laws are identically satisfied if the standard force balance holds. In approximate solutions, for example obtained by finite elements, the equilibrium is not satisfied exactly, thus configurational forces occur on discretization nodes. An implementation of the configurational force balance into the finite element scheme is presented. The use of configurational forces is discussed with three main aspects. It is demonstrated how configurational forces can be used to check and to improve the finite element solution. Examples from fracture mechanics and problems with material inhomogeneities are discussed. Copyright © 2001 John Wiley & Sons, Ltd.
Time‐discretized variational formulation of non‐smooth frictional contact
Authors: Pandolfi A. , Kane C. , Marsden J. E. , Ortiz M.
Published: October 2002

The present work extends the non‐smooth contact class of algorithms introduced by Kane et al. to the case of friction. The formulation specifically addresses contact geometries, e.g. involving multiple collisions between tightly packed non‐smooth bodies, for which neither normals nor gap functions can be properly defined. A key aspect of the approach is that the incremental displacements follow from a minimum principle. The objective function comprises terms which account for inertia, strain energy, contact, friction and external forcing. The Euler–Lagrange equations corresponding to this extended variational principle are shown to be consistent with the equations of motion of solids in frictional contact. In addition to its value as a basis for formulating numerical algorithms, the variational framework offers theoretical advantages as regards the selection of trajectories in cases of non‐uniqueness. We present numerical and analytical examples which demonstrate the good momentum and energy conservation characteristics of the numerical algorithms, as well as the ability of the approach to account for stick and slip conditions. Copyright © 2001 John Wiley & Sons, Ltd.
A control volume capacitance method for solidification modelling with mass transport
Authors: Davey K. , Rodriguez N. J.
Published: October 2002

Capacitance methods are popular methods used for solidification modelling. Unfortunately, they suffer from a major drawback in that energy is not correctly transported through elements and so provides a source of inaccuracy. This paper is concerned with the development and application of a control volume capacitance method (CVCM) to problems where mass transport and solidification are combined. The approach adopted is founded on theory that describes energy transfer through a control volume (CV) moving relative to the transporting mass. An equivalent governing partial differential equation is established, which is designed to be transformable into a finite element system that is commonly used to model transient heat‐conduction problems. This approach circumvents the need to use the methods of Bubnov–Galerkin and Petrov–Galerkin and thus eliminates many of the stability problems associated with these approaches. An integration scheme is described that accurately caters for enthalpy fluxes generated by mass transport. Shrinkage effects are neglected in this paper as all the problems considered involve magnitudes of velocity that make this assumption reasonable. The CV approach is tested against known analytical solutions and is shown to be accurate, stable and computationally competitive. Copyright © 2002 John Wiley & Sons, Ltd.
A precise computation of stress intensity factor on the front of a convex planar crack
Authors: Ascenzi Oscar , Pareschi Lorenzo , Segala Fausto
Published: October 2002

In this paper, we consider a general integral expression for mode I stress intensity factor along the fronts of convex planar cracks. For this integral approximation, we develop a simple numerical quadrature formula on every convex set Ω which allows a precise estimation of the error. This permits the use of extrapolation techniques for the accurate computation of the integral. Copyright © 2002 John Wiley & Sons, Ltd.
New soybean oil‐Styrene‐Divinylbenzene thermosetting copolymers—IV. Good damping properties
Authors: Li Fengkui , Larock Richard C.
Published: October 2002

New polymeric materials have been prepared by the cationic copolymerization of regular soybean oil, low saturation soybean oil, i.e. LoSatSoy oil, or conjugated LoSatSoy oil with styrene and divinylbenzene, norbornadiene or dicyclopentadiene initiated by boron trifluoride diethyl etherate (BF
3·OEt
2) or related modified initiators. The effects of the stoichiometry, the type of soybean oil and the alkene comonomer on the damping behavior of the resulting polymers have been investigated. The damping properties have been quantitatively evaluated by the loss tangent maximum (tan δ)
max, ­the temperature range ΔT for efficient damping (tan δ > 0.3), and the integrals of the linear tan δ v. temperature curves (tan δ area, TA). These bulk materials are composed primarily of soybean oil‐styrene‐divinylbenzene random copolymers with considerable variability in the backbone compositions. The good damping properties of the soybean oil polymers are presumably determined by the presence of fatty acid ester side groups directly attached to the polymer backbone and the segmental heterogeneities resulting from crosslinking. In general, crosslinking reduces the (tan δ)
max and the TA values, but broadens the region of efficient damping (ΔT). Soybean oil polymeric materials with appropriate compositions and crosslink densities are capable of efficiently damping over a temperature region in excess of 110 °C and provide noise and vibration attenuation over broad temperature and frequency ranges. Copyright © 2002 John Wiley & Sons, Ltd.
Comparative studies of osteoblast and fibroblast type I collagen in a patient with osteogenesis imperfecta type IV
Authors: Galicka Anna , Wolczynski Slawomir , Gindzienski Andrzej
Published: October 2002

The expression of type I collagen has been compared in fibroblast and osteoblast cultures of a patient with moderately severe osteogenesis imperfecta (OI) type IV, with respect to control cells. Electrophoretic analysis of type I collagen showed that both OI osteoblasts and fibroblasts synthesized normal chains and chains with delayed migration. However, the osteoblasts contained a higher proportion of abnormal chains than fibroblasts from the proband. Pulse‐chase experiments showed that the trimers containing abnormal chains were cleared more rapidly from osteoblasts than fibroblasts. Moreover, the collagen secreted by OI osteoblasts had thermal stability 1°C higher than collagen secreted by OI fibroblasts. These results suggest that the abnormal collagen in osteoblasts may be more resistant to intra‐ and extracellular degradation and may thus have better survival than in fibroblasts. This finding could have implications for understanding the clinical phenotype of OI. Copyright © 2001 John Wiley & Sons, Ltd.
Telemicroscopy by the Internet revisited
Authors: Brauchli K. , Christen H. , Haroske G. , Meyer W. , Kunze K. D. , Oberholzer M.
Published: October 2002

This paper reports a fundamentally new concept for internet‐based telemicroscopy. By separating a telemicroscopy application into three tasks – microscope control program, external server, and client application – it is possible to establish a telemicroscopy session between two arbitrary end points on the Internet even if both of the end points are secured by firewall (microscope and client application). The advantages of such a distributed system, compared with the classical point‐to‐point systems, are discussed. The telemicroscopy system is combined with a telepathology database, which is capable of automatically recording telemicroscopy sessions, allowing a convenient combination of interactive remote microscopy and store and forward telepathology. In addition to remote primary diagnosis, it is easily possible to discuss difficult cases within dedicated user groups, no matter whether images originate from a telemicroscopy session, or are manually entered into the database. Copyright © 2001 John Wiley & Sons, Ltd.
Lumican expression in alpha cells of islets in pancreas and pancreatic cancer cells
Authors: Ping Lu Yue , Ishiwata Toshiyuki , Asano Goro
Published: October 2002

Lumican is a member of a small leucine‐rich proteoglycan family, members of which play an important role in cell migration and proliferation during embryonic development, tissue repair, and tumour growth. Lumican is reported to be overexpressed during the wound healing process in the cornea and in human breast cancer tissues, but its expression and localization in normal pancreas and pancreatic cancer tissues are not known. The present study aimed to clarify the expression of lumican protein and its mRNA in human pancreatic cancer cell lines and their localization in normal and cancerous human pancreatic tissues. Reverse transcription‐polymerase chain reaction (RT‐PCR) and western blot analysis revealed lumican mRNA and its protein expression in PK‐8 and MIA‐PaCa‐2 human pancreatic cancer cells. The tumour lumican had non‐ or poorly sulphated polylactosamine side‐chains rather than highly sulphated keratan sulphate chains. Immunoreactivity of the lumican protein was localized in alpha cells of islets and stromal tissues of a normal pancreas. In pancreatic cancer tissues, the lumican protein was strongly localized in cancer cells, and in acinar and islet cells in chronic pancreatitis‐like lesions adjacent to the cancer cells. It was also localized in fibroblasts and collagen fibres close to cancer cells. Lumican mRNA was expressed in cancer cells, in acinar and islet cells in chronic pancreatitis‐like lesions, and in stromal fibroblasts in the pancreatic cancer tissues. This is the first report that lumican is synthesized in endocrine and cancer cells. Lumican protein may play a role in the maintenance of islet cell function in normal pancreas and the lumican protein synthesized by cancer cells, acinar and islet cells, and stromal fibroblasts may play a role in the growth of human pancreatic cancer cells. Copyright © 2001 John Wiley & Sons, Ltd.
Genetic pathways in the evolution of breast ductal carcinoma in situ
Authors: Farabegoli Fulvia , Champeme Marie‐Helene , Bieche Ivan , Santini Donatella , Ceccarelli Claudio , Derenzini Massimo , Lidereau Rosette
Published: October 2002

The patterns of allelic loss in 28 cases of pure ductal carcinoma in situ (DCIS) and 25 cases of DCIS associated with invasive ductal carcinoma (IDC) were compared, in order to define whether pure DCIS represented an earlier stage than DCIS associated with IDC in the progression ofbreast carcinoma. To this aim, the polymerase chain reaction (PCR) was performed on microdissected normal and neoplastic breast tissue, formalin‐fixed and paraffin‐embedded. Fifteen microsatellite markers were examined, on chromosomes 1p, 3p, 7q, 11q, 12p, 13q, 16q and 17q, mostly focused on regions altered in breast cancer. Loss of heterozygosity (LOH) was greater in pure DCIS than in the DCIS component associated with IDC for 11 out of 15 markers. The difference was statistically significant for D13S260 and D17S800 (p=0.008 and p=0.01, respectively). DCIS associated with IDC showed a lesser degree of alteration than the synchronous IDC component for ten out of 15 markers. In contrast, LOH at D11S1816 and D16S318 was lower in pure DCIS than in DCIS associated with IDC and even greater in the IDC component. These results confirm that DCIS is a possible but not an obligate precursor of invasive breast cancer and suggest that pure DCIS and DCIS associated with IDC may be genetically distinct. The evolution from DCIS to IDC may follow multiple pathways and not a linear model. Copyright © 2002 John Wiley & Sons, Ltd.
Identification of loci associated with putative recurrence genes in transitional cell carcinoma of the urinary bladder
Authors: Edwards Joanne , Duncan Pamela , Going James J. , Watters Amanda D. , Grigor Kenneth M. , Bartlett John M. S.
Published: October 2002

Following an earlier study linking monosomy 9 with recurrence of transitional cell carcinomas (TCCs) of the urinary bladder, 109 primary and recurrent TCCs (from 47 patients) were examined to explore genetic alterations at chromosome 9 associated with recurrence. Patient DNA was microdissected and extracted from archival tissue sections and analysed for loss of heterozygosity (LOH) at three regions on chromosome 9 where tumour suppressor genes (TSGs) are known to reside (INK 4A, DBC1, and TSC1). Patients were categorized into two groups, non‐recurrent TCC (NR, n=18) and recurrent TCC (REC, n=29). It was noted that 12% of NR tumours, compared with 54% of REC primary tumours (p=0.01), had LOH at all informative markers spanning the TSC1 region. The risk of recurrence was significantly higher in patients with deleted TSC1 than in those who retained the TSC1 region (p=0.035). Levels of LOH at DBC1 or INK 4A were not significantly different in NR tumours than in REC primary tumours and recurrence‐free survival was not affected by loss of either of these genes. Loss of all informative markers spanning chromosome 9 was observed in 0% of NR tumours compared with 25% of REC primary tumours (p=0.04). The probability of recurrence was also significantly increased in patients who had LOH at all informative markers spanning chromosome 9 (p=0.016), confirming earlier fluorescence in situ hybridization results. This study provides further evidence that recurrence in bladder cancer is a distinct event, with underlying molecular causes. It also identifies the TSC1 locus as a candidate for a TSG, which drives recurrence in a proportion of TCC patients. Loss of all informative markers, including those residing in the TSC1 region, spanning chromosome 9 was also linked to recurrence. Copyright © 2002 John Wiley & Sons, Ltd.
Expression of mucins (MUC1, MUC2, MUC5AC, and MUC6) and type 1 Lewis antigens in cases with and without Helicobacter pylori colonization in metaplastic glands of the human stomach
Authors: Teixeira Ana , David Leonor , Reis Celso A. , Costa Julia , Sobrinho‐Simões Manuel
Published: October 2002

Helicobacter pylori (H. pylori) causes gastritis and intestinal metaplasia (IM) that may evolve to gastric carcinoma. Paradoxically, IM leads to clearing of H. pylori, except for some cases in which it persists in damaging the mucosa. The objective of this study was to compare the profile of mucins and type 1 Lewis antigens in IM cases with and without H. pylori. Gastric biopsies (n=32) were double‐stained using immunohistochemistry (MUC1, MUC2, MUC5AC, MUC6, Lea, sialyl‐Lea, and Leb) and histochemistry for H. pylori. H. pylori was observed in association with IM in 4 of 22 biopsies with IM (complete IM – 6; incomplete IM – 16). The four biopsies with IM and H. pylori displayed a particular pattern of incomplete IM: expression of MUC1 and MUC5AC and little/no expression of MUC2. The 18 biopsies with IM and without H. pylori had high levels of MUC2 expression, regardless of the IM type. The pattern of expression of type 1 Lewis antigens was similar in IM, regardless of the presence or absence of H. pylori. It is concluded that H. pylori is able to colonize incomplete IM whenever it contains foci expressing MUC1 and MUC5AC and no MUC2, independently from Lea, sialyl‐Lea and Leb. The results suggest, furthermore, that MUC2 expression affects the ability of H. pylori to colonize IM areas, regardless of the levels of expression of MUC1 and MUC5AC. Copyright © 2002 John Wiley & Sons, Ltd.
A possible role for complement in the pathogenesis of chronic chagasic cardiomyopathy
Authors: Demarchi Aiello Vera , Martins Reis Márcia , Alberto Benvenuti Luiz , de Lourdes Higuchi Maria , Antonio Franchini Ramires José , Halperin José A.
Published: October 2002

The membrane attack complex (MAC) of complement participates in several inflammatory and proliferative processes by releasing pro‐inflammatory cytokines and growth factors from target cells. Chronic Chagasic cardiomyopathy (CCH) is a parasitic dilated cardiopathy, characterized by severe fibrosis and inflammation, which differs from idiopathic dilated cardiomyopathy (DCM). Trypanosoma cruzi, the pathogenic organism of CCH, is a strong complement activator and can also induce alternative pathway activation by mammalian cells. This study explored whether the myocardium in CCH patients has increased MAC deposition, an expression of complement activation, compared to DCM patients. MAC was semi‐quantified in endomyocardial human samples (29 CCH subjects, 18 DCM subjects, and four controls) by immunohistochemistry. MAC was present in the sarcolemma of 38% of CCH, 5.5% of DCM (p<0.02), and 0% of controls, and in interstitial inflammatory cells of CCH. No difference was observed in the expression of the complement regulatory protein CD59, indicating that increased MAC deposition is likely to be the result of complement activation rather than decreased protection. It is proposed that the increased MAC deposition found in CCH, but not in DCM or controls, may help to explain the diffuse myocardial fibrosis and inflammation characteristic of the disease. Copyright © 2002 John Wiley & Sons, Ltd.
Lung epithelial stem cells
Authors: Otto W. R.
Published: October 2002

This review concentrates on recent evidence about lung stem cell origins and plasticity. The range of potential cells which can repopulate the injured lung, classically the basal and mucous secretory cells of the trachea, the Clara cells of the bronchiole, and the type II pneumocyte of the alveolus, has been extended to include the mucus‐gland duct cells of the trachea and bronchus. Some evidence suggests that there are variant Clara cells that lack cytochrome P‐450 and so are spared toxic activation of xenobiotics, and may aid bronchiolar repopulation after injury, such as with naphthalene. There may even be involvement of the neuroepithelial bodies or cells in this, though the evidence is not yet conclusive. The search for a resident pulmonary multipotent cell for repopulating any lung epithelium has not yet been successful. The picture remains similar to earlier conclusions, in that thelocalstem or precursor cell is the most likely to contribute to local needs in times of tissue damage. There remains a major challenge for lung cancer treatment, where high‐dose chemo‐ or radio‐therapy may be hoped to promote the seeding and repair of lung parenchyma by circulating bone marrow stem cells, as seen in liver models. Patient survival rates do not yet suggest that this occurs to any great extent, but this remains to be shown formally. The effects of prior fibrosis and tumour necrosis are probably confounding factors in this lack of rescue. Copyright © 2002 John Wiley & Sons, Ltd.
Chromosome 14q LOH in localized clear cell renal cell carcinoma
Authors: Mitsumori Kenji , Kittleson John M. , Itoh Noriyuki , Delahunt Brett , Heathcott Rosemary W. , Stewart John H. , McCredie Margaret R. E. , Reeve Anthony E.
Published: October 2002

The progression of a malignant tumour is understood to be the result of the accumulation of multiple genetic aberrations. As up to 14% of organ‐confined renal cell carcinomas will recur after surgery, tumour clones with metastatic potential must already be present in some of these localized tumours. The association of 14q LOH with high‐grade tumours and advanced tumour stage suggests an important role for the gene in tumour progression. Chromosome 14q LOH has been analysed in microdissected specimens from 130 organ‐confined (UICC TNM stage 1 and 2) clear cell renal cell carcinomas using three microsatellite markers (D14S588, D14S617, GATA136B01). Tumours were classified as 14q LOH or not on the basis of LOH at one or more of the markers. The allelic imbalance ratio was used to determine both LOH and LOH proportion and the association between LOH and mortality, tumour size, histological grade and growth kinetics, measured by quantification of nucleolar organizer regions, was analysed. 14q LOH was present in 35.4% of informative cases at marker D14S588, 24.4% at D14S617, 36.4% at GATA136B01 and 39.5% for any one of the three markers. The mean 14q LOH proportion was 0.24 (range 0.009–0.80). LOH proportion correlated significantly with tumour size, AgNOR score and histological grade. It was also significantly associated with disease‐specific mortality; (hazard ratio 1.22; 95% CI 1.02–1.45; p = 0.039). LOH proportion did not remain significant after adjusting for tumour size (hazard ratio 0.98; 95% CI 0.76–1.27; p = 0.90). These results indicate that the proportion of cells with 14q LOH in the tumour is associated with tumour aggressiveness; while this is not an independent predictor of survival, it may have some utility as a marker of latent metastatic potential. Copyright © 2002 John Wiley & Sons, Ltd.
Allotype imbalance or microsatellite mutation in low‐grade soft tissue sarcomas of the extremities in adults
Authors: Hoon Cho Nam , Cordon‐Cardo Carlos , Li G. C. , Hyun Kim See
Published: October 2002

The ability to repair DNA double‐strand breaks is essential to maintain chromosomal stability. Virtually all soft tissue sarcomas contain chromosomal instabilities, including clonal aberrations and cytogenetic aberrations. However, the relevance of DNA‐dependent protein kinase (DNA‐PK) in the pathogenesis of soft tissue sarcoma has not been clarified. The main aim of this work is to compare the prognostic impact of genotypic imbalance in low‐grade soft tissue sarcomas of the extremities, and to correlate this with the translational level of DNA‐PK. This study investigated 28 adult low‐grade malignant spindle cell tumours of the extremities, predominantly fibrosarcomas, for loss of heterozygosity (LOH) and microsatellite mutation on flanking regions of each DNA‐PK subunit, with identical immunophenotypes. Twelve different polymorphic markers flanking the specific loci of three subunits comprise the genetic map of DNA‐PK, at 22q13, 2q35, and 8q11. Translational activity was also analysed by western blot and conventional immunohistochemistry. The overall sarcoma 5‐year survival rate was 61.7%. LOH was identified in the specific coding region of DNA‐PK in 39.29% for the DNA‐PK catalytic subunit (cs), 17.86% for Ku70, and only 7.14% for Ku80. A positive LOH for DNA‐PKcs was shown to be a significant factor for poor survival (log rank test p = 0.0160). Immunoreactivity and immunoblot results correlated with the loss of DNA‐PKcs allotype in soft tissue sarcoma (Fisher's exact test p = 0.0037). Ku70 and DNA‐PKcs were almost identical in terms of immunoreactivity. In conclusion, whereas microsatellite mutation seems an uncommon event during the evolution of low‐grade fibrosarcoma of the extremities in adults, the loss of DNA‐PKcs defines a biologically more aggressive subset. Copyright © 2002 John Wiley & Sons, Ltd.