bluuebunny/crossref_metadata_2025_split huggingface dataset:
Selective induction of gene expression in rat lung by hexavalent chromium
Authors: Izzotti Alberto , Cartiglia Cristina , Balansky Roumen , D'Agostini Francesco , Longobardi Mariagrazia , De Flora Silvio 
Published: October 2002

AbstractMultigene‐expression analysis provides a formidable tool for evaluating cellular functions, under either physiological or pathological conditions, and for assessing their modulation by exogenous agents. We investigated multigene expression in the liver and lung of rats receiving intratracheal instillations of sodium dichromate for 3 consecutive days. Nylon membrane cDNA arrays were hybridized with standardized amounts of 32P‐labeled probes, and the results were normalized by making reference to housekeeping genes. The basal expression of 52 of 216 tested genes was 2.1–11.1 times higher in the liver than in the lung of control rats. No alteration of gene expression occurred in the liver of chromium(VI)‐treated rats, consistent with the fact that this metal species, being reduced upstream, can exert effects only locally but not at a distance from the respiratory tract. In contrast, the expression of 56 genes was increased 2.1 to 3.0 times in the lung as an early response to chromium(VI) administration. The altered genes are involved in the metabolic reduction of chromium(VI) and in a variety of interconnected functions, such as multidrug resistance and stress response, protein and DNA repair mechanisms, signal transduction pathways, apoptosis, and cell‐cycle modulation. Thus, short‐term treatment with chromium(VI) by intratracheal administration triggered a variety of defense processes in the lung. Although the use of selected genes does not provide an exhaustive picture of overall gene expression, these findings contribute to our understanding of chromium toxicology and provide a further mechanistic support to the involvement of thresholds in chromium(VI) carcinogenesis. © 2002 Wiley‐Liss, Inc.
Executive and emotional dysfunction in Machado‐Joseph disease
Authors: Zawacki Tricia M. , Grace Janet , Friedman Joseph H. , Sudarsky Lewis 
Published: October 2002

AbstractMachado‐Joseph disease (MJD) is an autosomal dominant spinocerebellar ataxia. Few studies have examined the neuropsychological and neurobehavioral profiles of patients with MJD. In this study, six individuals with MJD were given a battery of neuropsychological tests. Relative impairments on timed verbal attention tasks and verbal fluency (Stroop, Oral Symbol Digit Modalities, and Controlled Oral Word Association Test) were found. Other executive impairments also were seen on the Wisconsin Card Sorting Test, independent of motor dysfunction severity. Moderate‐ to severe levels of depressive symptoms were endorsed by four of the six patients, and caregivers observed increased apathy in the patients. Impaired executive and emotional functioning in MJD does not appear to be related to ataxia severity. These patients did not meet the criteria for dementia. General cognitive abilities, language, list learning, story recall, and untimed tasks of attention were within normal limits. Impaired executive abilities and emotional functioning in MJD patients is consistent with disruption of frontal‐subcortical systems. © 2002 Movement Disorder Society.
Olanzapine treatment for dopaminergic‐induced hallucinations
Authors: Ondo William G. , Levy Joel K. , Vuong Kevin Dat , Hunter Christine , Jankovic Joseph 
Published: October 2002

AbstractAtypical antipsychotic medications with lower affinities for D2 receptors are considered useful alternatives to treat drug‐induced hallucinations in Parkinson's disease (PD). We conducted a double‐blind, placebo‐controlled, unforced titration, parallel design study (2:1 drug to placebo randomization ratio) using olanzapine (2.5–10 mg/day to effect) in 30 PD patients with drug‐induced hallucinations. We performed an extensive battery of neuropsychological tests, the Unified Parkinson's Disease Rating Scale (UPDRS), assessments of on and off time at baseline and at 9 weeks after starting the medication. Sixteen patients on olanzapine (mean dose, 4.6 mg/night) and 11 on placebo completed the study. Compared with placebo, performance on the UPDRS item 2 (thought disorder), and a structured interview for hallucinations, both tended to improve on drug but neither reached statistical significance. A neuropsychological test battery did not show any significant differences. Total on UPDRS motor scores (P < 0.05) and timed tapping (P < 0.01) worsened while on drug compared to placebo. Bradykinesia (P < 0.01) and gait (P < 0.001) items on the UPDRS largely accounted for this deterioration. After completion of the study, 8 of 16 patients randomly assigned to drug continued olanzapine at a mean dose of 2.4 mg/day. However, at the last recorded visit only 5 of 24 (20.8%) of all patients exposed to drug (including those originally randomly assigned to placebo) remained on olanzapine. In patients with PD, low‐dose olanzapine did not significantly improve hallucinations but did worsen motor function. © 2002 Movement Disorder Society
Rev response elements (RRE) in lentiviruses: An RNAMotif algorithm‐based strategy for RRE prediction
Authors: Lesnik Elena A. , Sampath Ranga , Ecker David J. 
Published: October 2002

AbstractLentiviruses (a sub‐family of the retroviridae family) include primate and non‐primate viruses associated with chronic diseases of the immune system and the central nervous system. All lentiviruses encode a regulatory protein Rev that is essential for post‐transcriptional transport of the unspliced and incompletely spliced viral mRNAs from nuclei to cytoplasm. The Rev protein acts via binding to an RNA structural element known as the Rev responsive element (RRE). The RRE location and structure and the mechanism of the Rev‐RRE interaction in primate and non‐primate lentiviruses have been analyzed and compared. Based on structural data available for RRE of HIV‐1, a two step computational strategy for prediction of putative RRE regions in lentivirus genomes has been developed. First, the RNAMotif algorithm was used to search genomic sequence for highly structured regions (HSR). Then the program RNAstructure, version 3.6 was used to calculate the structure and thermodynamic stability of the region of ∼ 350 nucleotides encompassing the HSR. Our strategy correctly predicted the locations of all previously reported lentivirus RREs. We were able also to predict the locations and structures of potential RREs in four additional lentiviruses. © 2002 Wiley Periodicals, Inc. Med Res Rev, 22, No. 6, 617–636, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/med.10027
Input impedance of rectangular microstrip antennas on nonradiating edges
Authors: Kundu T. R. , Kar R. , Chatterjee S. , Hazra N. , Chakraborty H. , Kesh A. , Chakraborty J. , Sengupta T. , Roy S. , Bhattacharjee A. K. 
Published: October 2002

AbstractClosed‐form expressions for the input impedance of half‐wavelength rectangular microstrip antennas fed by a coaxial line at any point on any one of the nonradiating edges and open‐circuited at the ends are derived. Good agreement between computed and measured data is obtained. © 2002 Wiley Periodicals, Inc. Microwave Opt Technol Lett 33: 28–31, 2002; DOI 10.1002/mop.10221
J‐modulated 1D directed COSY for precise measurement of proton–proton residual dipolar coupling constants of oligosaccharides
Authors: Pham Tran N. , Liptaj Tibor , Barlow Paul N. , Uhrín Dušan 
Published: October 2002

AbstractA simple selective 1D experiment for the accurate and precise determination of residual proton–proton dipolar coupling constants of oligosaccharides is proposed. The technique is based on the concept of J‐modulated spectroscopy and provides coupling constants by fitting the peak intensities from a series of spectra to known transfer functions with a precision of ±0.02 Hz for splittings >0.3 Hz. This level of precision is possible owing to limiting the number of sites for polarization transfer. Selective pulses and pulsed field gradients are used for selective excitation and coherence selection, yielding clean, artefact‐free spectra. The technique is illustrated using trisaccharide samples in Pf1 phage. Copyright © 2002 John Wiley & Sons, Ltd.
Cerebral venous and arterial blood volumes can be estimated separately in humans using magnetic resonance imaging
Authors: An Hongyu , Lin Weili 
Published: October 2002

AbstractApproaches to obtain quantitative, noninvasive estimates of total cerebral blood volume (tCBV) and cerebral venous blood volume (vCBV) separately in humans are proposed. Two sequences were utilized, including a 3D high‐resolution gradient‐echo (GE) sequence and a 2D multi‐echo GE/spin‐echo (MEGESE) sequence. Images acquired by the former sequence provided an estimate of background magnetic field variations (ΔB), while images obtained by the latter sequence were utilized to obtain separate measures of tCBV and vCBV with and without contrast agent. Prior to the calculation of vCBV and tCBV, the acquired images were corrected for signal loss induced by the presence of ΔB. vCBV and tCBV were estimated to be 2.46% ± 0.28% and 3.20% ± 0.41%, respectively, after the ΔB correction, which in turn provided a vCBV/tCBV ratio of 0.77 ± 0.04, in excellent agreement with results reported in the literature. Our results demonstrate that quantitative estimates of vCBV and tCBV can be obtained in vivo. Magn Reson Med 48:583–588, 2002. © 2002 Wiley‐Liss, Inc.
Asymmetrical gradient coil for head imaging
Authors: Tomasi D. , Xavier R.F. , Foerster B. , Panepucci H. , Tannús A. , Vidoto E.L. 
Published: October 2002

AbstractThis work presents a novel approach to develop dedicated transverse gradient coils for head imaging. The proposed coil design is based on the stochastic optimization of an asymmetrical stream function and improves the matching between the region‐of‐interest and the homogeneous gradient volume. Additionally, the electric field produced by these asymmetrical coils is 30% lower than that produced by standard symmetrical designs, which minimizes the risk of magnetostimulation of nerves in fast imaging techniques. A prototype of the asymmetrical gradient coil was built to test the method and magnetic field produced by the prototype was measured. Magnetic field measurements and electrical parameters of coils are in good agreement with theoretical calculations. Magn Reson Med 48:707–714, 2002. © 2002 Wiley‐Liss, Inc.
Increased choline levels coincide with enhanced proliferative activity of human neuroepithelial brain tumors
Authors: Herminghaus Sebastian , Pilatus Ulrich , Möller‐Hartmann Walter , Raab Peter , Lanfermann Heinrich , Schlote Wolfgang , Zanella Friedhelm E. 
Published: October 2002

AbstractProton MR spectroscopy (1H MRS)‐visible total choline‐containing compounds (tCho‐compounds) are derivatives of membrane phospholipids and, in part, may act as a long‐term second‐messenger system for cellular proliferation. Experimental evidence suggests increasing concentrations of tCho‐compounds during cellular proliferation. The present study was conducted in order to test the hypothesis that in vivo measurements of tCho‐concentrations using 1H MRS allow assessment of the proliferative activity of neuroepithelial brain tumors presurgically. Single‐voxel 1H MRS (PRESS, TR 1500 ms, TE 135 ms) was performed in 101 patients with neuroepithelial brain tumors prior to surgery and 19 healthy volunteers. Histological diagnoses were confirmed postsurgically according to the WHO classification. Measured tCho‐compound signal intensities were corrected for coil loading, numbers of acquisitions and voxel size, and tCho concentrations calculated as institutional arbitrary units. They were matched with the mean immunohistochemical marker of cell proliferation, the Ki‐67 (MIB.1) labeling index, using correlation analysis according to Spearman. Compared with low‐grade tumors (i.e. WHO grade I/II) and normal white brain matter, high‐grade tumors (i.e. WHO grade III/IV) revealed significantly (p < 0.05) elevated labeling indices paralleled by increasingly elevated tCho‐concentrations. In contrast tCho‐concentrations in low‐grade tumor did not differ significantly from physiological values. A highly significant positive correlation (p < 0.0001, r2 = 0.81) was found between the tCho‐concentration and the labeling index. It was concluded that the determination of tCho‐concentrations using in vivo 1H MRS could provide a novel and noninvasive assessment of the proliferative activity of neuroepithelial brain tumors, pointing at 1H MRS as a useful method for differentiating proliferating from non‐proliferating tissues. Hence, potential indications for the clinical application of 1H MRS are grading tumors presurgically, early detection of anaplastic transformation, and monitoring treatment. Copyright­© 2002 John Wiley & Sons, Ltd.
Node‐disjoint paths and related problems on hierarchical cubic networks
Authors: Fu Jung‐Sheng , Chen Gen‐Huey , Duh Dyi‐Rong 
Published: October 2002

AbstractAnn‐dimensional hierarchical cubic network [denoted by HCN(n)] contains 2nn‐dimensional hypercubes. The diameter of the HCN(n), which is equal ton+ ⌊(n+ 1)/3⌋ + 1, is about two‐thirds the diameter of a comparable hypercube, even though it uses about half as many links per node. In this paper, a maximal number of node‐disjoint paths are constructed between every two distinct nodes of the HCN(n). Their maximal length is bounded above byn+ ⌊n/3⌋ + 4, which is nearly optimal. The (n+ 1)‐wide diameter andn‐fault diameter of the HCN(n) are shown to ben+ ⌊n/3⌋ + 3 orn+ ⌊n/3⌋ + 4, which are about two‐thirds those of a comparable hypercube. Our results reveal that the HCN(n) has a smaller wide diameter and fault diameter than those of a comparable hypercube. © 2002 Wiley Periodicals, Inc.
Overexpression of Parkinson's disease‐associated α‐SynucleinA53T by recombinant adeno‐associated virus in mice does not increase the vulnerability of dopaminergic neurons to MPTP
Authors: Dong Zhizhong , Ferger Boris , Feldon Joram , Büeler Hansruedi 
Published: October 2002

AbstractMutations in the α‐synuclein gene are linked to a rare dominant form of familial Parkinson's disease, and α‐synuclein is aggregated in Lewy bodies of both sporadic and dominant Parkinson's disease. It has been proposed that mutated α‐synuclein causes dopaminergic neuron loss by enhancing the vulnerability of these neurons to a variety of insults, including oxidative stress, apoptotic stimuli, and selective dopaminergic neurotoxins, such as 1‐methyl‐4‐phenyl‐1,2,3,6‐tetrahydropyridine (MPTP). To test this hypothesis in vivo, we overexpressed human α‐synucleinA53T in the substantia nigra of normal and MPTP‐treated mice by rAAV‐mediated gene transfer. Determination of dopaminergic neuron survival, striatal tyrosine hydroxylase fiber density, and striatal content of dopamine and its metabolites in rAAV‐injected and uninjected hemispheres demonstrated that α‐synucleinA53T does not increase the susceptibility of dopaminergic neurons to MPTP. Our findings argue against a direct detrimental role for (mutant) α‐synuclein in oxidative stress and/or apoptotic pathways triggered by MPTP, but do not rule out the possibility that α‐synuclein aggregation in neurons exposed to oxidative stress for long periods of time may be neurotoxic. © 2002 Wiley Periodicals, Inc. J Neurobiol 53: 1–10, 2002
Application of the three‐way decomposition for matrix compression
Authors: Ibraghimov Ilghiz 
Published: October 2002

AbstractWe present a new method to compress and invert 3D integral operators on rectangular non‐regular grids. This method requires a small amount of memory to store the compressed matrix and in most cases can provide a good preconditioner for the solution of linear systems with this matrix. We demonstrate efficiency of this method for the solution of some model discrete problems associated with
∫A(x̄,ȳ)f(x̄)dx̄=u(ȳ), x̄,ȳϵℝ3
, where A(x̄,ȳ) such as 1/∣x̄−ȳ∣ is considered on a non‐regular grid. The arithmetical complexity of matrix–vector and preconditioner–vector multiplications are about N4/3 operations and there are only about N2/3 words of memory to store. Copyright © 2002 John Wiley & Sons, Ltd.
Directional bilateral asymmetry in human sacral morphology
Authors: Plochocki Jeffrey H. 
Published: October 2002

AbstractDirectional bilateral asymmetries in human gross skeletal morphology are largely attributable to differential mechanical loading from handedness during endochondral bone growth. While much has been done in the way of identifying directional asymmetries of the upper limb in relation to handedness, comparatively little research has focused on asymmetry in the lower body. The present paper analyses asymmetry in the human sacrum in a sample of 238 modern individuals. Measurements of right and left sides of the lateral and posterior breadths of the alae and the maximum height of the auricular surface were used. Asymmetry was calculated as: [(left side − right side) ÷ right side] * 100. Directional asymmetry was identified using a one‐sample t‐test against a hypothesized mean of zero. Significant directional asymmetry (P < 0.05) was found in all three dimensions. The pattern of asymmetry is consistent with models describing the influence of right‐handedness on the lower body, which predicts that left side dimensions will be larger. Copyright © 2002 John Wiley & Sons, Ltd.
The effect of child support on welfare exits and re‐entries
Authors: Huang Chien‐Chung , Kunz James , Garfinkel Irwin 
Published: October 2002

AbstractMuch of the literature on welfare dynamics has focused on the effects of recipient characteristics and state‐level characteristics such as welfare benefits and economic conditions; there has been very little analysis on the effects of child support. This paper, using the 1979‐1996 National Longitudinal Survey of Youth, examines whether child support affects the likelihood of leaving and re‐entering welfare. The results indicate that strong child support enforcement is important in helping young mothers exit and stay off welfare. Women with $1000 child support payments in the previous year were 18 percent more likely to exit welfare and 12 percent less likely to re‐enter welfare. Compared with women in states that pursued child support least vigorously, women in states that had passed extensive child support enforcement legislation and that spent more money on child support enforcement were 79 percent more likely to exit welfare and about 60 percent less likely to re‐enter welfare. © 2002 by the Association for Public Policy Analysis and Management.
Does it pay to move from welfare to work?
Authors: Danziger Sheldon , Heflin Colleen M. , Corcoran Mary E. , Oltmans Elizabeth , Wang Hui‐Chen 
Published: October 2002

AbstractThe 1996 Personal Responsibility and Work Opportunity Reconciliation Act requires welfare recipients to look
for work and has made it more difficult for nonworking recipients to remain on the welfare rolls. In addition,
the economic boom of the 1990s and changes in federal and state policies have raised the net income gain
associated with moving from welfare to work. This paper analyzes data from a panel survey of single mothers, all
of whom received welfare in February 1997. In 1999, those who left welfare and were working had a higher
household income and lower poverty rate, experienced a similar level of material hardship, engaged in fewer
activities to make ends meet, and had lower expectations of experiencing hardship in the near future than did
nonworking welfare recipients. Estimations of fixed‐effect regressions of income that control for both
observable and unobservable time‐invariant characteristics show that monthly net income increases by
$2.63 for every additional hour of work effort. About 60 percent of the observed monthly income
difference between wage‐reliant and welfare‐reliant mothers can be attributed to differences in
their work effort. Thus, after welfare reform, it does pay to move from welfare to work. © 2002 by the
Association for Public Policy Analysis and Management.
Transcription factor E2F‐1 acts as a growth‐promoting factor and is associated with adverse prognosis in non‐small cell lung carcinomas
Authors: Gorgoulis Vassilis G. , Zacharatos Panayotis , Mariatos George , Kotsinas Athanassios , Bouda Martha , Kletsas Dimitris , Asimacopoulos Panayiotis J. , Agnantis Niki , Kittas Christos , Papavassiliou Athanasios G. 
Published: October 2002

AbstractNumerous upstream stimulatory and inhibitory signals converge to the pRb/E2F pathway, which governs cell‐cycle progression, but the information concerning alterations of E2F‐1 in primary malignancies is very limited. Several in vitro studies report that E2F‐1 can act either as an oncoprotein or as a tumour suppressor protein. In view of this dichotomy in its functions and its critical role in cell cycle control, this study examined the following four aspects of E2F‐1 in a panel of 87 non‐small cell lung carcinomas (NSCLCs), previously analysed for defects in the pRb‐p53‐MDM2 network: firstly, the status of E2F‐1 at the protein, mRNA and DNA levels; secondly, its relationship with the kinetic parameters and genomic instability of the tumours; thirdly, its association with the status of its transcriptional co‐activator CBP, downstream target PCNA and main cell cycle regulatory and E2F‐1‐interacting molecules pRb, p53 and MDM2; and fourthly, its impact on clinical outcome. The protein levels of E2F‐1 and its co‐activator CBP were significantly higher in the tumour area than in the corresponding normal epithelium (p<0.001). E2F‐1 overexpression was associated with increased E2F‐1 mRNA levels in 82% of the cases examined. The latter finding, along with the low frequency of E2F‐1 gene amplification observed (9%), suggests that the main mechanism of E2F‐1 protein overexpression in NSCLCs is deregulation at the transcriptional level. Mutational analysis revealed only one sample with asomatic mutation at codon 371 (Glu→Asp) and one carrying a polymorphism at codon 393 (Gly→Ser). Carcinomas with increased E2F‐1 positivity demonstrated a significant increase in their growth indexes (r=0.402, p=0.001) and were associated with adverse prognosis (p=0.033 by Cox regression analysis). The main determinant of the positive association with growth was the parallel increase between E2F‐1 staining and proliferation (r=0.746, p<0.001), whereas apoptosis was not influenced by the status of E2F‐1. Moreover, correlation with the status of the pRb–p53–MDM2 network showed that the cases with aberrant pRb expression displayed significantly higher E2F‐1 indexes (p=0.033), while a similar association was noticed in the group of carcinomas with deregulation of the p53–MDM2 feedback loop. In conclusion, the results suggest that E2F‐1 overexpression may contribute to the development of NSCLCs by promoting proliferation and provide evidence that this role is further enhanced in a genetic background with deregulated pRb–p53–MDM2 circuitry. Copyright © 2002 John Wiley & Sons, Ltd.