bluuebunny/crossref_metadata_2025 huggingface dataset:
Value of fine needle aspiration biopsy in childhood rhabdomyosarcoma: Twenty‐six years of experience in Slovenia
Authors: Pohar‐Marinšek Živa , Anžič Jožica , Jereb Berta
Published: August 2002

Background

Chemotherapy (Cht) for rhabdomyosarcoma (RMS) given before local treatment can prevent mutilating surgery and high‐dose irradiation (RT). Fine needle aspiration biopsy (FNAB) can confirm the diagnosis and neoadjuvant treatment can start without delay. The purpose of our study was to assess the role of FNAB in the management of childhood RMS in Slovenia.

Procedure

A total of 78 children and young adults were included. FNAB provided the pre‐treatment diagnosis in 37 and surgical biopsy in 41 patients. In 61 cases recurrent/metastatic disease was aspirated. Cytological diagnoses were compared to the original histological diagnoses. All case histories, cytological and histological material were reviewed and immunocytochemical staining performed when necessary.

Results

FNAB provided a correct diagnosis of malignancy in all 37 primary tumours, a specific diagnosis of RMS was given in 29 (78%). With the use of immunocytochemistry during the last 15 years, the accuracy has risen to 87%. FNAB provided the diagnosis of recurrence/metastasis in 57/61 cases. No complications of FNAB were noted. Review of histology reclassified five original diagnoses of RMS into one malignant rhabdoid tumour and four sarcomas NOS. In review of cytology we were able to sub classify 80% of RMS.

Conclusions

FNAB is a safe method, which enables us to establish the pre‐treatment diagnosis of RMS, and to some extent even its type, without delay. In our study, FNAB successfully replaced surgical biopsy in 87% of RMS patients during the last 15 years. Neoadjuvant Cht was started immediately, surgery was delayed and more conservative. Consequently, the risk for treatment sequelae was considerably reduced. Med Pediatr Oncol 2002;38:416–420. © 2002 Wiley‐Liss, Inc.
Novel alternatively spliced mRNA (1c) of the protein kinase A RIα subunit is implicated in haploid germ cell specific expression
Authors: Dahle Maria K. , Reinton Nils , Ørstavik Sigurd , Taskén Kristin A. , Taskén Kjetil
Published: August 2002

By using 5′ RACE on rat testis cDNA we identified three alternatively spliced mRNAs of the RIα subunit of cAMP‐dependent protein kinase that differed in their 5′ untranslated regions. Two of these 5′‐regions showed similarity with the human RIα exons 1a and 1b, while the third (1c) constituted a novel mRNA splice variant. Northern blot analysis showed that the 1c mRNA was specifically expressed in testis and only in postmeiotic germ cells. In contrast, the RIα 1b and RIα 1a mRNAs were present both in premeiotic germ cells and somatic cells of the testis, and the expression of both RIα 1a and 1b mRNAs were stimulated by cAMP in Sertoli cells. In sperm, the RIα protein was expressed after meiosis, and targeted to various subcellular structures via anchoring proteins. The RIα 1c haploid‐specific mRNA, therefore, may be important for the regulation of RIα expression in sperm. Mol. Reprod. Dev. 59:11–16, 2001. © 2001 Wiley‐Liss, Inc.
Assessment of metabolism of equine morulae and blastocysts
Authors: Lane M. , O'Donovan M.K. , Squires E.L. , Seidel G.E. , Gardner D.K.
Published: August 2002

Nutrient uptakes and metabolite production by equine morula and blastocyst stage embryos were determined by non‐invasive microfluorometry. Equine morula took up equal amounts of both pyruvate and glucose. However, at the early blastocyst there was a small increase in glucose uptake and, by the expanded blastocyst stage, glucose was the predominant nutrient. Expanded blastocysts took up five times more glucose than pyruvate. Expanded blastocysts exhibited an exponential increase in glucose uptake and lactate production with respect to both diameter and surface area. As less than 50% of the glucose was accounted for by lactate production, the equine blastocyst appears to have a significant capacity to oxidize glucose. Embryos with a higher morphological grade consumed more nutrients than those with a poorer morphology. However, there was a large range in nutrient consumption within the highest grade blastocysts. This suggests that nutrient uptake may be useful as a viability marker of equine blastocysts. Mol. Reprod. Dev. 59:33–37, 2001. © 2001 Wiley‐Liss, Inc.
Stage of the estrous cycle at the time of pregnant mare's serum gonadotropin injection affects the quality of ovulated oocytes in the mouse
Authors: Tarín Juan J. , Pérez‐Albalá Sonia , Cano Antonio
Published: August 2002

The present study aims to analyze the effect of the stage of the estrous cycle at the time of pregnant mare's serum gonadotropin (PMSG) injection on number and quality of mouse oocytes retrieved from oviducts after exogenous ovarian stimulation. Cellular and morphological traits of ovulated oocytes from hybrid (C57Bl/6JIco female X CBA/JIco male) female mice of 12, 40–42, 50–52 or 57–62 weeks of age were analyzed. Superovulation was induced by a priming injection of PMSG at different stages of the estrous cycle followed after a 48‐hr interval by human chrorionic gonadotropin. Injection of PMSG at diestrus‐1 was associated with: (1) increased percentage of cumulus‐free oocytes; (2) raised total percentage of oocytes without polar body; (3) increased total percentage of oocytes with intracytoplasmic mitochondrial aggregates; (4) decreased percentage of oocytes with a normal distribution of chromosomes in the metaphase II plate; and (5) raised percentage of oocytes with chromosome scattering when compared to injection at estrus, diestrus‐2, and proestrus stage. On the contrary, estrus females displayed the highest percentage of oocytes with a normal distribution of chromosomes in the metaphase II plate and the lowest percentage of oocytes denuded of cumulus cells, without polar body, with intracytoplasmic mitochondrial aggregates and/or with chromosome scattering. These data suggest that administration of gonadotropins in mice should be synchronized with the innate estrous cycle of females to optimize the quality of oocytes collected from oviducts.Mol. Reprod. Dev. 61: 398–405, 2002. © 2002 Wiley‐Liss, Inc.
Isolation and characterization of sea urchin egg lipid rafts and their possible function during fertilization
Authors: Belton Robert J. , Adams Nikki L. , Foltz Kathy R.
Published: August 2002

Specialized membrane microdomains called rafts are thought to play a role in many types of cell–cell interactions and signaling. We have investigated the possibility that sea urchin eggs contain these specialized membrane microdomains and if they play a role in signal transduction at fertilization. A low density, TX‐100 insoluble membrane fraction, typical of lipid rafts, was isolated by equilibrium gradient centrifugation. This raft fraction contained proteins distinct from cytoskeletal complexes. The fraction was enriched in tyrosine phosphorylated proteins and contained two proteins known to be involved in signaling during egg activation (an egg Src‐type kinase and PLCγ). This fraction was further characterized as a prototypical raft fraction by the release of proteins in response to in vitro treatment of the rafts with the cholesterol binding drug, methyl‐β‐cyclodextrin (MβCD). Furthermore, treatment of eggs with MβCD inhibited fertilization, suggesting that egg lipid rafts play a physiological role in fertilization. Mol. Reprod. Dev. 59:294–305, 2001. © 2001 Wiley‐Liss, Inc.
Soluble tubulin complexes in oocytes of the common leopard frog, Rana pipiens, contain γ‐tubulin
Authors: Lessman Charles A. , Kim Haekwon
Published: August 2002

Oocytes of the leopard frog, Rana pipiens, contain soluble tubulin which was previously shown to exist predominately in megadalton (MDa) fractions and that fails to readily assemble in vitro. In order to further characterize these tubulin complexes, DEAE Sepharose chromatography, Sephacryl S‐300 size exclusion columns and specific immunoprecipitation were used. The results revealed the presence of α‐, β‐, and γ‐tubulin associated with several other proteins in the soluble fraction of Rana pipiens ovarian oocytes. These Rana oocyte tubulin complexes appear to be analogous to those recently reported in Xenopus ovulated eggs as γ‐tubulin ring complexes. This seems true since both size (estimates, i.e. ∼2MDa) and protein components are similar. Furthermore, both α‐ and γ‐tubulin antibodies immunoprecipitated identical protein bands from Rana oocyte soluble fraction. These putative Rana γ‐tubulin ring proteins include 107, 97, 95, 90 and 75 kDa components which are similar in size to those found in Xenopus and other species. Rana appears to belong to a select group in which γ‐tubulin complexes contain significant α‐ and β‐tubulin (i.e., Xenopus and sheep), while other species such as Drosophila, Aspergillus, Saccharomyces, human cells and many other mammalian cells tested lack the other tubulin components. The heterogeneity in both size and protein components of Rana oocyte γ‐tubulin ring complexes may reflect different states of tubulin complex assembly. The lower vertebrate oocyte is hypothesized to act as a repository and prestaging point for the assembly of γ‐tubulin ring complexes which will become the maternal contribution to the centrosomes of the embryo. While the γ‐tubulin ring complexes of vertebrate eggs have been described previously, this is the first report biochemically characterizing soluble γ‐tubulin complexes in vertebrate ovarian oocytes. Mol. Reprod. Dev. 60: 128–136, 2001. © 2001 Wiley‐Liss, Inc.
Relationships between diffusion tensor andq‐space MRI†
Authors: Basser Peter J.
Published: August 2002

Fundamental relationships between diffusion tensor (DT) and 3Dq‐space MRI are derived which establish conditions when these two complementary MR methods are equivalent. It is shown that the displacement distribution measured byq‐space MRI in both the large displacement (i.e., large r) and the long‐wavelength (i.e., smallq) limits is the same 3D Gaussian displacement distribution assumed in DT‐MRI. In these limiting cases,q‐space MR yields a dispersion tensor that is identical to the effective DT,D, measured in DT‐MRI. An experiment is then proposed to measureDusingq‐space methods. These findings establish that the effective DT, measured in DT‐MRI, characterizes molecule motions on a coarse length‐scale. Finally, the feasibility of and requirements for performing 3Dq‐space MRI on a clinical scanner are considered. Magn Reson Med 47:392–397, 2002. Published 2002 Wiley‐Liss, Inc.
Mohr diagram representation of anisotropic diffusion tensor in MRI
Authors: Bilgen Mehmet , Elshafiey Ibrahim , Narayana Ponnada A.
Published: August 2002

With current approaches, it is difficult to visually comprehend the complete information contained in a diffusion tensor (DT) measured from a microscopically heterogeneous biological tissue. Therefore, in this work the Mohr diagram is introduced to graphically display the key aspects of DTs and to interpret the underlying anisotropy, both qualitatively and quantitatively. Specifically, the mathematical basis for the construction of the Mohr diagram from the elements of DTs is described, the merits of the approach are illustrated with examples of DTs reported for various biological tissues, and the results are discussed in the context of relating the diffusion anisotropy to the tissue structures. Magn Reson Med 47:823–827, 2002. © 2002 Wiley‐Liss, Inc.
Biexponential modeling of multigradient‐echo MRI data of the brain
Authors: Speck O. , Ernst T. , Chang L.
Published: August 2002

Functional MRI (fMRI) using fast multigradient‐echo acquisition methods allows the quantitative determination of the relevant parameter T. Previously, the TE‐dependent signal decay has been modeled with a monoexponential function despite the complex composition of the brain. In this study, biexponential modeling was used to evaluate the relaxation of brain parenchyma and blood separate from that of cerebrospinal fluid. Single‐shot multigradient‐echo data acquired with spiral or EPI techniques were analyzed. In phantom experiments the biexponential method proved to be accurate. Compared to the biexponential procedure, the monoexponential model overestimated T (72.2 msec vs. 65.3 msec) and underestimated ΔT (2.96 msec vs. 3.19 msec) during visual stimulation. The biexponential method may allow intrinsic correction for partial volume effects due to cerebrospinal fluid. The activation‐induced parameter changes are detected with a sensitivity equal to that of a monoexponential method. The resulting T and ΔT values describe the experimental data more accurately. Magn Reson Med 45:1116–1121, 2001. © 2001 Wiley‐Liss, Inc.
Simultaneous acquisition of multiple resolution images for dynamic contrast enhanced imaging of the breast
Authors: Song Hee Kwon , Dougherty Lawrence , Schnall Mitchell D.
Published: August 2002

An imaging technique is described that allows the reconstruction of a series of images at high temporal rates, while simultaneously providing images at high spatial resolution. The method allows one to arbitrarily choose from among several combinations of temporal/spatial resolutions during postprocessing. This flexibility is accomplished by strategically interleaving multiple undersampled projection reconstruction datasets (or subapertures), in which each set can be used to reconstruct a high temporal resolution image. Images with increasingly higher spatial resolutions can subsequently be formed by combining two or more subaperture datasets. The technique is demonstrated in vivo to assess the kinetics of contrast enhancement and to visualize the architectural features of suspicious breast lesions. Magn Reson Med 46:503–509, 2001. © 2001 Wiley‐Liss, Inc.
Parallel expression of neurotrophic factors and their receptors in chronic inflammatory demyelinating polyneuropathy
Authors: Yamamoto Masahiko , Ito Yasuhiro , Mitsuma Norimasa , Li Mei , Hattori Naoki , Sobue Gen
Published: August 2002

The mRNA levels of nerve growth factor (NGF), glial cell line–derived neurotrophic factor (GDNF), ciliary neurotrophic factor (CNTF), leukemia inhibitory factor (LIF), and interleukin‐6 (IL‐6) were examined in sural nerves of 22 patients with chronic inflammatory demyelinating polyneuropathy (CIDP). The mRNAs for NGF, GDNF, LIF, and IL‐6 were upregulated, whereas CNTF mRNA was downregulated significantly in the nerves. The NGF, GDNF, and CNTF, but not LIF mRNA expressions were parallel to those of the cognate receptors, suggesting that these cognate soluble receptors effectively present these factors to maintain and regenerate the axons. Furthermore, IL‐6 mRNA expression was significantly parallel to both binding and signal‐transducing receptor expression, implying a role of the IL‐6 signal for non‐neuronal cells in CIDP. These findings indicate that multiple neurotrophic growth factors and cytokines are expressed cooperatively with their concomitant receptors in the nerve lesions of CIDP and play an important role particularly in nerve repair. © 2002 Wiley Periodicals, Inc. Muscle Nerve 25: 000–000, 2002
Adaptations in maximal motor unit discharge rate to strength training in young and older adults
Authors: Patten Carolynn , Kamen Gary , Rowland Daniel M.
Published: August 2002

Six young (mean = 23 years) and 6 older (mean = 76 years) adults participated in isometric resistance training 5 days/week for 6 weeks. The task involved isometric fifth finger abduction. Maximal motor unit discharge rates (MUDRs) were obtained from the abductor digiti minimi of each hand at 0, 2, 14, and 42 days of training using a quadrifilar needle electrode and automatic spike recognition software. In agreement with previous findings, maximal MUDR at baseline was significantly lower in older adults (P < 0.001), averaging 51.5 (±17.13) HZ in young and 43.3 (±14.88) HZ in older adults. In response to resistance training, maximal voluntary force increased 25% in young and 33% in older subjects (P < 0.001). Maximal MUDR increased significantly (11% young, 23% older) on day 2 [F(3,36) = 2.58, P < 0.05], but in older subjects returned to baseline levels thereafter. These adaptations in abductor digiti minimi MUDR suggest a two‐part response to strengthening fifth finger abduction: early disinhibition followed by altered MU activation.© 2001 John Wiley & Sons, Inc. Muscle Nerve 24:542–550, 2001
More on the search for an infiltrator
Authors: Pavlović Ljiljana
Published: August 2002

We have asymptotically solved a discrete search game on an array of n ordered cells with two players: infiltrator (hider) and searcher, when the probability of survival approaches 1. The infiltrator wishes to reach the last cell in finite time, and the searcher has to defend that cell. When the players occupy the same cell, the searcher captures the infiltrator with probability 1 − z. The payoff to the hider is the probability that the hider reaches the last cell without getting captured. © 2002 John Wiley & Sons, Inc. Naval Research Logistics, 49: 1–14, 2002; DOI 10.1002/nav.1047
Measurement of intravascular Na+ during increased CBF using 23Na NMR with a shift reagent
Authors: Ronen Itamar , Kim Seong‐Gi
Published: August 2002

Sodium ions are intimately involved with neural activity. Thus, it is highly desirable to devise a way of mapping brain activity via sodium imaging. Sodium ions exist in the extravascular and intravascular spaces. To separate the two components, the shift reagent Tm(DOTP)5− was intravenously introduced into rats. Intravascular sodium changes in the rat brain were measured during increased blood flow induced by hypercapnia using volume‐localized 23Na‐NMR. The intravascular sodium changes, equivalent to cerebral blood volume changes, are significant during hypercapnia conditions and correlate well with the increase in arterial pCO2. This suggests that the intravascular sodium change is dominant in total 23Na spectroscopy or imaging of the brain during blood flow increase induced by external perturbation. Copyright © 2001 John Wiley & Sons, Ltd.
The function and the expression of forebrain GABAA receptors change with hormonal state in the adult mouse
Authors: Jorge Juan Carlos , McIntyre Kerry L. , Henderson Leslie P.
Published: August 2002

Neurotransmission mediated by gamma‐aminobutyric acid type A (GABAA) receptors in the mammalian medial preoptic area (mPOA) plays a pivotal role in the expression of hormone‐sensitive behaviors. Hand in hand with GABAergic control of reproduction, hormone treatments that activate gonadal steroid signaling pathways in gonadectomized rats are known to regulate the expression of specific GABAA receptor subunit mRNAs. While the effects of exogenous hormone treatments have been well documented, little information is available as to how GABAA receptor‐mediated transmission in the mPOA is altered by endogenous changes in hormonal state in gonadally‐intact adult animals or if those changes can be ascribed to hormone‐dependent changes in receptor subunit composition. In the present study, we found that both the peak amplitudes of GABAA receptor‐mediated synaptic currents in the mPOA, as well as the ability of the endogenous neurosteroids to modulate those currents, varied as a function of the estrous cycle. Moreover, we found that the degree of neurosteroid modulation was also significantly different between wild‐type and the androgen‐insensitive testicular feminization (Tfm) mutant male mice. Semiquantitative RT‐PCR analysis performed to assess levels of GABAA receptor subunit mRNAs indicated that levels of specific subunits varied over the course of the estrous cycle and between wild‐type and Tfm male mice. The variations in GABAA receptor expression and function in the mPOA that are associated with differences in gonadal steroid signaling may contribute to the dynamic nature of GABAergic control of neuroendocrine pathways. © 2002 Wiley Periodicals, Inc. J Neurobiol 50: 137–149, 2002; DOI 10.1002/neu.10021
Spike‐triggered dendritic calcium transients depend on synaptic activity in the cricket giant interneurons
Authors: Ogawa Hiroto , Baba Yoshichika , Oka Kotaro
Published: August 2002

The relationship between electrical activity and spike‐induced Ca2+ increases in dendrites was investigated in the identified wind‐sensitive giant interneurons in the cricket. We applied a high‐speed Ca2+ imaging technique to the giant interneurons, and succeeded in recording the transient Ca2+ increases (Ca2+ transients) induced by a single action potential, which was evoked by presynaptic stimulus to the sensory neurons. The dendritic Ca2+ transients evoked by a pair of action potentials accumulated when spike intervals were shorter than 100 ms. The amplitude of the Ca2+ transients induced by a train of spikes depended on the number of action potentials. When stimulation pulses evoking the same numbers of action potentials were separately applied to the ipsi‐ or contra‐lateral cercal sensory nerves, the dendritic Ca2+ transients induced by these presynaptic stimuli were different in their amplitude. Furthermore, the side of presynaptic stimulation that evoked larger Ca2+ transients depended on the location of the recorded dendritic regions. This result means that the spike‐triggered Ca2+ transients in dendrites depend on postsynaptic activity. It is proposed that Ca2+ entry through voltage‐dependent Ca2+ channels activated by the action potentials will be enhanced by excitatory synaptic inputs at the dendrites in the cricket giant interneurons. © 2002 Wiley Periodicals, Inc. J Neurobiol 50: 234–244, 2002; DOI 10.1002/neu.10032
Respiratory units of motor production and song imitation in the zebra finch
Authors: Franz Michele , Goller Franz
Published: August 2002

Juvenile male zebra finches (Taeniopygia guttata) learn a stereotyped song by imitating sounds from adult male tutors. Their song is composed of a series of syllables, which are separated by silent periods. How acoustic units of song are translated into respiratory and syringeal motor gestures during the song learning process is not well understood. To learn about the respiratory contribution to the imitation process, we recorded air sac pressure in 38 male zebra finches and compared the acoustic structures and air sac pressure patterns of similar syllables qualitatively and quantitatively. Acoustic syllables correspond to expiratory pressure pulses and most often (74%) entire syllables are copied using similar air sac pressure patterns. Even notes placed within different syllables are generated with similar air sac pressure patterns when only segments of syllables are copied (9%). A few of the similar syllables (17%) are generated with a modified pressure pattern, typically involving addition or deletion of an inspiration. The high similarity of pressure patterns for like syllables indicates that generation of particular sounds is constrained to a narrow range of air sac pressure conditions. Following presentation of stroboscope flashes, song was typically interrupted at the end of an expiratory pressure pulse, confirming that expirations and, therefore, syllables are the smallest unit of motor production of song. Silent periods, which separate syllables acoustically, are generated by switching from expiration to inspiration. Switching between respiratory phases, therefore, appears to play a dominant role in organizing the stereotyped motor program for song production. © 2002 Wiley Periodicals, Inc. J Neurobiol 51: 129–141, 2002
Sex differences in progesterone receptor immunoreactivity in neonatal mouse brain depend on estrogen receptor α expression
Authors: Wagner Christine K. , Pfau Jennifer L. , De Vries Geert J. , Merchenthaler Istvan J.
Published: August 2002

Around the time of birth, male rats express higher levels of progesterone receptors in the medial preoptic nucleus (MPN) than female rats, suggesting that the MPN may be differentially sensitive to maternal hormones in developing males and females. Preliminary evidence suggests that this sex difference depends on the activation of estrogen receptors around birth. To test whether estrogen receptor alpha (ERα) is involved, we compared progesterone receptor immunoreactivity (PRir) in the brains of male and female neonatal mice that lacked a functional ERα gene or were wild type for the disrupted gene. We demonstrate that males express much higher levels of PRir in the MPN and the ventromedial nucleus of the neonatal mouse brain than females, and that PRir expression is dependent on the expression of ERα in these regions. In contrast, PRir levels in neocortex are not altered by ERα gene disruption. The results of this study suggest that the induction of PR via ERα may render specific regions of the developing male brain more sensitive to progesterone than the developing female brain, and may thereby underlie sexual differentiation of these regions. © 2001 John Wiley & Sons, Inc. J Neurobiol 47: 176–182, 2001
Regulation of the pharynx of Caenorhabditis elegans by 5‐HT, octopamine, and FMRFamide‐like neuropeptides
Authors: Rogers Candida M , Franks Christopher J. , Walker Robert J. , Burke Julian F. , Holden‐Dye Lindy
Published: August 2002

More than fifty FMRFamide‐like neuropeptides have been identified in nematodes. We addressed the role of a subset of these in the control of nematode feeding by electrophysiological recording of the activity of C. elegans pharynx. AF1 (KNEFIRFamide), AF2 (KHEYLRFamide), AF8 (KSAYMRFamide), and GAKFIRFamide (encoded by the C. elegans genes flp‐8, flp‐14, flp‐6, and flp‐5, respectively) increased pharyngeal action potential frequency, in a manner similar to 5‐HT. In contrast, SDPNFLRFamide, SADPNFLRFamide, SAEPFGTMRFamide, KPSVRFamide, APEASPFIRFamide, and AQTVRFamide (encoded by the C. elegans genes flp‐1; flp‐1; flp‐3; flp‐9; flp‐13, and flp‐16, respectively) inhibited the pharynx in a manner similar to octopamine. Only three of the neuropeptides had potent effects at low nanomolar concentrations, consistent with a physiological role in pharyngeal regulation. Therefore, we assessed whether these three peptides mediated their actions either directly on the pharynx or indirectly via the neural circuit controlling its activity by comparing actions between wild‐type and mutants with deficits in synaptic signaling. Our data support the conclusion that AF1 and SAEPFGTMRFamide regulate the activity of the pharynx indirectly, whereas APEASPFIRFamide exerts its action directly. These results are in agreement with the expression pattern for the genes encoding the neuropeptides (Kim and Li, 1999) as both flp‐8 and flp‐3 are expressed in extrapharyngeal neurons, whereas flp‐13 is expressed in I5, a neuron with synaptic output to the pharyngeal muscle. These results provide the first, direct, functional information on the action of neuropeptides in C. elegans. Furthermore, we provide evidence for a putative inhibitory peptidergic synapse, which is likely to have a role in the control of feeding. © 2001 John Wiley & Sons, Inc. J Neurobiol 49: 235–244, 2001
A perturbation method for stochastic meshless analysis in elastostatics
Authors: Rahman S. , Rao B. N.
Published: August 2002

A stochastic meshless method is presented for solving boundary‐value problems in linear elasticity that involves random material properties. The material property was modelled as a homogeneous random field. A meshless formulation was developed to predict stochastic structural response. Unlike the finite element method, the meshless method requires no structured mesh, since only a scattered set of nodal points is required in the domain of interest. There is no need for fixed connectivities between nodes. In conjunction with the meshless equations, classical perturbation expansions were derived to predict second‐moment characteristics of response. Numerical examples based on one‐ and two‐dimensional problems are presented to examine the accuracy and convergence of the stochastic meshless method. A good agreement is obtained between the results of the proposed method and Monte Carlo simulation. Since mesh generation of complex structures can be a far more time‐consuming and costly effort than the solution of a discrete set of equations, the meshless method provides an attractive alternative to finite element method for solving stochastic mechanics problems. Copyright © 2001 John Wiley & Sons, Ltd.
Aspects of the computational testing of the mechanical properties of microheterogeneous material samples
Authors: Zohdi T. I. , Wriggers P.
Published: August 2002

In this paper we investigate topics related to the numerical simulation of the testing of mechanical responses of samples of microheterogeneous solid material. Consistent with what is produced in dispersion manufacturing methods, the microstructures considered are generated by randomly distributing aggregates of particulate material throughout an otherwise homogeneous matrix material. Therefore, the resulting microstructures are irregular and non‐periodic. A primary problem in testing such materials is the fact that only finite‐sized samples can be tested, leading to no single response, but a distribution of responses. In this work, a technique employing potential energy principles is presented to interpret the results of testing groups of samples. Three‐dimensional numerical examples employing the finite element method are given to illustrate the overall analysis and computational testing process. Copyright © 2001 John Wiley & Sons, Ltd.
A splitting positive definite mixed element method for miscible displacement of compressible flow in porous media
Authors: Yang Danping
Published: August 2002

A miscible displacement of one compressible fluid by another in a porous medium is governed by a nonlinear parabolic system. A new mixed finite element method, in which the mixed element system is symmetric positive definite and the flux equation is separated from pressure equation, is introduced to solve the pressure equation of parabolic type, and a standard Galerkin method is used to treat the convection‐diffusion equation of concentration of one of the fluids. The convergence of the approximate solution with an optimal accuracy in L2‐norm is proved. © 2001 John Wiley & Sons, Inc. Numer Methods Partial Differential Eq 17: 229–249, 2001
Family survivorship and quality of life following a cancer diagnosis
Authors: Mellon Suzanne , Northouse Laurel L.
Published: August 2002

The objectives of this study were: (a) to examine the quality of life of the family as a unit during the long‐term survivor phase of illness and (b) to test a family model of factors that may influence family quality of life. The family survivorship model, which includes illness survival stressors (family stressors, fear of recurrence, and patient somatic concerns), resources (family hardiness and family social support), appraisal (family meaning of the illness), and the outcome, family quality of life, was used to guide this exploratory cross‐sectional study. A random, stratified sample of 123 families (N = 246 individuals) was interviewed 1–5 years after treatment ended. The model explained 63% of the variance in family quality of life, with the strongest predictors being concurrent family stressors, family social support, family member fear of recurrence, family meaning of the illness, and patient employment status. The study findings suggest the importance of addressing cancer‐related stressors, family resources, and family meaning as key factors related to family quality of life. © 2001 John Wiley & Sons, Inc. Res Nurs Health 24:446–459, 2001
Prevalence, prevention, and treatment of pressure ulcers: Descriptive study in 89 institutions in The Netherlands
Authors: Bours Gerrie J.J.W. , Halfens Ruud J.G. , Abu‐Saad Huda Huijer , Grol Richard T.P.M.
Published: August 2002

The purpose of the present study was to assess the prevalence of pressure ulcers and the use of Dutch guidelines for the prevention and treatment of pressure ulcers. A survey of 16,344 patients in 89 health care institutions on 1 day showed a mean prevalence of pressure ulcers of 23.1%. It was found that Dutch guidelines on some aspects of prevention and treatment of pressure ulcers were not being followed. Only 53% of the patients who should have been positioned on a support surface were positioned on such a device. Fewer than one‐third of the patients who should have been repositioned, should have received nutritional support, or should have been educated received these interventions, and only 33.6% of all pressure ulcers were dressed as recommended. More attention to the dissemination and implementation of the guidelines is needed to reduce this high prevalence of pressure ulcers. © 2002 Wiley Periodicals, Inc. Res Nurs Health 25:99–110, 2002
National and supranational government–NGO relations: anti‐discrimination policy formation in the European Union
Authors: Bouget Denis , Prouteau Lionel
Published: August 2002

This article explores the implications of internationalization for national government–NGO and national‐NGO and international NGO relations, and NGO policy influence at national and international levels. Internationalization is defined as supranational problem solving. Following a brief overview of national and international issues of government–NGO relations, the article describes European Union (EU)‐NGO interactions. A case illustration on the EU's policy directives on equal treatment and anti‐discrimination highlights a mutually supportive relationship between national and international NGO coalitions and their respective lobbying efforts at national and international levels. The case reveals how supranational governing bodies can play a role in galvanizing NGO activities and movements potentially contributing to cost‐effective, technically informed, and publicly supported policy initiatives. It further demonstrates how NGOs can create parallel federation structures to support policy influence at multiple levels. Copyright © 2002 John Wiley & Sons, Ltd.
The expression of Ki‐67, MCM3, and p27 defines distinct subsets of proliferating, resting, and differentiated cells
Authors: Endl Elmar , Kausch Ingo , Baack Martina , Knippers Rolf , Gerdes Johannes , Scholzen Thomas
Published: August 2002

The mini‐chromosome maintenance proteins (MCM), which are involved in the control of DNA replication, and the cyclin‐dependent kinase inhibitors, such as p27/KIP1, represent two groups of proteins that are currently under investigation as diagnostic tumour markers. The expression of p27 and MCM3 was compared with the expression of the Ki‐67 protein, an approved marker for proliferating cells, extensively used in histopathology and cancer research. The expression pattern of all three proteins was assessed on germinal centres and oral mucosa, which display a well‐defined spatio‐temporal organization. The expression of the p27 protein was closely related to differentiated cells, whereas MCM3 and Ki‐67 were predominantly localized to the regions of proliferating cells. However, it is important to note that considerable numbers of cells that were growth‐arrested, as confirmed by the absence of the Ki‐67 protein, stained positive for the MCM3 protein. These results were verified in vitro using growth‐arrested Swiss 3T3. The MCM3 protein is therefore expressed in cells that have ceased to proliferate, but are not terminally differentiated, according to the absence of p27 protein expression. In conclusion, a combined analysis of Ki‐67, MCM3, and p27 protein expression may provide a more detailed insight into the cell proliferation and differentiation processes that determine individual tumour growth. Copyright © 2001 John Wiley & Sons, Ltd.
Expression of basal cell keratins in human prostate cancer metastases and cell lines
Authors: van Leenders Geert J. L. H. , Aalders Tilly W. , Hulsbergen‐van de Kaa Christina A. , Ruiter Dirk J. , Schalken Jack A.
Published: August 2002

Within normal human prostate epithelium, basal and luminal cells can be discriminated by their expression of keratins (K). While basal cells express K5/14, luminal cells show expression of K8/18 and an intermediate cell population can be identified by co‐expression of K5/18. Prostate cancer is predominantly composed of luminal and neuroendocrine cells, while a minority of cells have a basal phenotype. In order to distinguish between basal and intermediate cells, and to assess the effects of androgen deprivation on prostate cancer, 56 human prostate cancer metastases and three cancer cell lines were characterized using antibodies to K5, K14, K18, and the neuroendocrine marker chromogranin A (ChA). The staining was performed on paraffin tissue and visualized by the avidin–biotin–peroxidase complex method. Protein expression was quantified as the number of positive cells in 20 high power fields (HPF; 400×). Keratin expression in the prostate cancer cell lines LNCaP, DU145, and PC3 was analysed by immunofluorescence with triple staining and confocal laser scanning microscopy. Prostate cancer metastases were consistently positive for K18 and negative for K14, irrespective of hormonal therapy. K5 expression was displayed in 28.9% of the tumours without treatment, in 75% after androgen deprivation, and in 57.1% of hormone‐escaped prostate carcinomas. After androgen deprivation, the number of K5‐expressing cells increased significantly. While androgen‐dependent prostate cancer showed a median of 0 cells/20 HPF (range 0–50), regressed tumours displayed 22.5 (range 0–65) and hormone‐escaped tumours 7.5 (range 0–361) positive cells/20 HPF. Expression of ChA was observed in 47.4% of the androgen‐dependent tumours. The number of neuroendocrine cells was not significantly affected in regressed or hormone‐escaped disease. The androgen‐dependent cell line LNCaP stained for K18, while the androgen‐independent lines DU145 and PC3 both expressed K5 and 18. Expression of K5 in the absence of K14 identifies the existence of an intermediate cell population in prostate carcinoma. Accumulation of intermediate cells in regressed and hormone‐escaped prostate cancer indicates that for their survival, these cells are androgen‐independent. Copyright © 2001 John Wiley & Sons, Ltd.
Quantitative determination of ginsenosides by high‐performance liquid chromatography‐tandem mass spectrometry
Authors: Ji Qin C. , Harkey Martha R. , Henderson Gary L. , Eric Gershwin M. , Stern Judith S. , Hackman Robert M.
Published: August 2002

An HPLC‐MS/MS method was developed for the quantitative determination of ginsenosides, which are the marker compounds for herbal products containing Panax ginseng (Korean or Chinese ginseng) and P. quinquefolius (American ginseng). Samples were extracted with BondElut® C18 HF extraction columns and the concentrations of seven major ginsenosides (Rb1, Rb2, Rc, Rd, Re, Rf, and Rg1) were determined by reversed‐phase HPLC‐MS/MS employing a quadrupole‐ion trap mass spectrometer. Both positive and negative electrospray ionisation techniques were evaluated. Positive ionisation spectra of these compounds gave strong sodium adduct molecular and sodium adduct dimer ions. Negative ionisation yielded the molecular ion primarily and was, therefore, used for analysis: quantitative determination was based on the most abundant product ions for each ginsenoside. The method was used to extract and analyse commercial samples of P. ginseng and P. quinquefolius. Copyright © 2001 John Wiley & Sons, Ltd.
Characterisation of soy isoflavones and screening for novel malonyl glycosides using high‐performance liquid chromatography–electrospray ionisation–mass spectrometry
Authors: Gu Liwei , Gu Wenying
Published: August 2002

HPLC combined with electrospray ionisation (ESI)‐MS and photodiode array detection has been employed to study the isoflavone components of soy. All of the known soy isoflavones separated by HPLC were identified and characterised, and three novel isoflavones were detected and screened out. These minor isoflavones were deduced to be isomers of 6″‐O‐malonyl isoflavone glycosides, based on the ESI‐MS and UV data, in which the malonyl group is attached at a position other than the 6″ position of the glycosyl moiety of the molecule. These novel malonyl glycosides are as thermally labile as the 6″‐O‐malonyl glycosides, being converted into known isoflavone glycosides after heating in aqueous ethanol. The advantages of HPLC‐ESI‐MS in detection of novel isoflavones from plant extracts are reviewed. Copyright © 2001 John Wiley & Sons, Ltd.
Comparative differential scanning calorimetric analysis of vegetable oils: II. Effects of cooling rate variation
Authors: Man Y. B. Che , Tan C. P.
Published: August 2002

The effects of scanning rates (1, 5, 10 and 20°C/min) on the DSC cooling profiles of 11 vegetable oils have been determined in order to monitor peak transition temperatures, onset temperatures and crystallisation enthalpies. Triacylglycerol (TAG) profiles and iodine value analyses were used to complement the DSC data. The melted samples exhibited complicated crystallising exotherms. As the cooling rate increased, the crystallisation temperature decreased and the breadth of the crystallisation exotherm on cooling from the melt increased. In addition, the intensity of the exothermic peak increased somewhat when the cooling rate was increased. At slow cooling rates, TAG had more time to interact. It is conceivable that, at a low cooling rate (1°C/min), a prominent exotherm would be observed on crystallisation of vegetable oils and fats. The occurrence of one exotherm upon cooling indicated the co‐crystallisation of the TAG upon slow cooling. On the basis of the corollary results obtained, vegetable oils may be differentiated by their onset temperature (Ton) values in the DSC cooling curves. Generally, there was a shift of Ton toward lower values with increasing cooling rates. Copyright © 2002 John Wiley & Sons, Ltd.
Effect of fetal gender on first trimester markers and on Down syndrome screening
Authors: Yaron Yuval , Wolman Igal , Kupferminc Michael J. , Ochshorn Yifat , Many Ariel , Orr‐Urtreger Avi
Published: August 2002

Objectives

The purpose of the present study was to evaluate whether a gender‐related difference exists in first trimester markers used for Down syndrome screening, namely nuchal translucency (NT), maternal serum pregnancy‐associated plasma protein‐A (PAPP‐A), and free β‐human chorionic gonadotrophin (β‐hCG), and whether this has an influence on screening performance.

Methods

A total of 1325 patients with a singleton pregnancy underwent combined first trimester screening at 10–13 weeks' gestation. Maternal serum PAPP‐A and free β‐hCG were analyzed by fluoroimmunoassay, nuchal translucency (NT) was measured by transvaginal sonography. Only patients with normal outcomes and known fetal gender were included in the study. Data were categorized by gestational age and by fetal gender.

Results

There were no significant gender‐related differences in NT and PAPP‐A levels. However, free β‐hCG was significantly higher (p=0.00004) in the presence of a female fetus than in the presence of a male fetus. Women with female fetuses had a higher median calculated Down syndrome risk (1:5490) compared to those having males (1:6451). This difference was not, however, statistically significant.

Conclusion

First trimester free β‐hCG is significantly higher in pregnancies with a female fetus. Copyright © 2001 John Wiley & Sons, Ltd.
Duplex systems
Authors: M Whitten S. , Wilcox D. T.
Published: August 2002

Duplex kidneys occur in 0.8% of the general population, many of whom are asymptomatic. Children with duplex kidneys may be prone to urinary tract infections because of vesico‐ureteric reflux or obstruction. Surgical management is usually required once symptoms occur. Increasing numbers of duplex kidneys are now prenatally diagnosed by ultrasound, resulting in the development of early postnatal strategies to try and reduce morbidity. Copyright © 2001 John Wiley & Sons, Ltd.
Evaluation of prenatal diagnosis of associated congenital heart diseases by fetal ultrasonographic examination in Europe
Authors: Stoll C. , Garne E. , Clementi M. ,   EUROSCAN Study Group
Published: August 2002

Ultrasound scans in the mid trimester of pregnancy are now a routine part of antenatal care in most European countries. With the assistance of Registries of Congenital Anomalies a study was undertaken in Europe. The objective of the study was to evaluate prenatal detection of congenital heart defects (CHD) by routine ultrasonographic examination of the fetus. All congenital malformations suspected prenatally and all congenital malformations, including chromosome anomalies, confirmed at birth were identified from the Congenital Malformation Registers, including 20 registers from the following European countries: Austria, Croatia, Denmark, France, Germany, Italy, Lithuania, Spain, Switzerland, The Netherlands, UK and Ukrainia. These registries follow the same methodology. The study period was 1996–1998, 709 030 births were covered, and 8126 cases with congenital malformations were registered. If more than one cardiac malformation was present the case was coded as complex cardiac malformation. CHD were subdivided into ‘isolated’ when only a cardiac malformation was present and ‘associated’ when at least one other major extra cardiac malformation was present. The associated CHD were subdivided into chromosomal, syndromic non‐chromosomal and multiple. The study comprised 761 associated CHD including 282 cases with multiple malformations, 375 cases with chromosomal anomalies and 104 cases with non‐chromosomal syndromes. The proportion of prenatal diagnosis of associated CHD varied in relation to the ultrasound screening policies from 17.9% in countries without routine screening (The Netherlands and Denmark) to 46.0% in countries with only one routine fetal scan and 55.6% in countries with two or three routine fetal scans. The prenatal detection rate of chromosomal anomalies was 40.3% (151/375 cases). This rate for recognized syndromes and multiply malformed with CHD was 51.9% (54/104 cases) and 48.6% (137/282 cases), respectively; 150/229 Down syndrome (65.8%) were livebirths. Concerning the syndromic cases, the detection rate of deletion 22q11, situs anomalies and VATER association was 44.4%, 64.7% and 46.6%, respectively. In conclusion, the present study shows large regional variations in the prenatal detection rate of CHD with the highest rates in European regions with three screening scans. Prenatal diagnosis of CHD is significantly higher if associated malformations are present. Cardiac defects affecting the size of the ventricles have the highest detection rate. Mean gestational age at discovery was 20–24 weeks for the majority of associated cardiac defects. Copyright © 2001 John Wiley & Sons, Ltd.
The comorbidities of obesity
Authors: Webber Jonathan
Published: August 2002

Obesity is a major risk factor for a number of diseases. It has direct effects on glucose and lipid metabolism and on blood pressure, leading via these to type 2 diabetes, coronary heart disease and cerebrovascular disease. These comorbidities are particularly associated with excess intra‐abdominal fat. Other important diseases which obesity increases the risks of include obstructive sleep apnoea, osteoarthritis of weight‐bearing joints and a number of types of cancer. In addition to these medical comorbidities obesity has many adverse social and psychological costs. Copyright © 2001 John Wiley & Sons, Ltd.