bluuebunny/crossref_metadata_2025 huggingface dataset:
A scale to measure the cognitive control form of perceived control: Construction and preliminary assessment
Authors: Faranda William T.
Published: August 2002

This article explores the notion that the evaluation process for services may include some variables not typically associated with the evaluation of physical goods. Evidence exists that enhanced perceptions of control may contribute to the pleasantness of service experiences. Although three forms of perceived control—behavioral, decisional, and cognitive—have been utilized as experimental manipulations of individuals' control, established measures exist for the first two forms only. Through two studies, this research develops a measure for perceived cognitive control and reports exploratory modeling with the construct within the disconfirmation paradigm and extensive tests of the measure's validation. The two‐dimensional scale evidences unidimensionality, strong internal consistency, and convergent and discriminant validity. Assessment of relationships between the perceived cognitive control scale and numerous, related constructs supports criterion‐related validity and nomological validity. © 2001 John Wiley & Sons, Inc.
Compound‐specific isotope analysis of the organic constituents in carbonaceous chondrites
Authors: Sephton M. A. , Gilmour I.
Published: August 2002

I.
Introduction
111

II.
Stable Isotopes
112

III.
CSIA
112

IV.
CSIA of Organic Compounds from Carbonaceous Chondrites
115

A.  Carbon
115

B.  Nitrogen
118

C.  Sulfur
118

D.  Hydrogen
118

V.
History of Meteoritic Organic Matter
118

Acknowledgments
118

References
118

The carbonaceous chondrite meteorites contain evidence of the formation of the solar system, part of which is present within organic matter. In recent years, compound‐specific isotope analysis (CSIA) has been useful in deciphering this complex record. The current published data set provides an insight into the source environments and reaction mechanisms that have contributed to the final state of the organic constituents in carbonaceous chondrites. This review summarises the CSIA data and related key interpretations. © 2001 John Wiley & Sons, Inc., Mass Spec Rev 20:111–120, 2001
2‐methoxyestradiol blocks cell‐cycle progression at G2/M phase and inhibits growth of human prostate cancer cells
Authors: Kumar Addanki P. , Garcia Gretchen E. , Slaga Thomas J.
Published: August 2002

2‐Methoxyestradiol (2‐ME), an endogenous metabolite of 17β‐estradiol, is present in human blood and urine. Here we show for the first time that 2‐ME significantly inhibited the growth of normal prostate epithelial cells and androgen‐dependent LNCaP and androgen‐independent DU145 prostate cancer cells. This growth inhibition was accompanied by a twofold increase in the G2/M population, with a concomitant decrease in the G1 population, as shown by cell‐cycle analysis. 2‐ME treatment affected the cell‐cycle progression of prostate cancer cells specifically by blocking cells in the G2 phase. Immunoblot analysis of the key cell‐cycle regulatory proteins in the G2/M phase showed a 14‐fold increase in the expression of p21 and an eightfold increase in the expression of p34 cell division cycle 2 (cdc2). We also found an accumulation of phosphorylated cdc2 after 2‐ME treatment. Furthermore, Wee 1 kinase was detectable after 2‐ME treatment. 2‐ME treatment also led to an increase in the activity of caspase‐3, followed by apoptosis, as shown by terminal deoxynucleotidyl transferase–mediated deoxyuridine 5‐triphosphate–biotin nick end‐labeling and fluorescein isothiocyanate–poly(ADP‐ribose) polymerase assay. Estrogen receptor levels did not change after treatment with 2‐ME. Examination of the signaling pathways that mediate 2‐ME–induced apoptosis showed reduction in the level of p53 expression and its DNA‐binding activity. Given the fact that p53 mutations are common in patients with metastatic prostate cancer, our finding that 2‐ME–mediated growth inhibition of human prostate cancer cells occurred in a p53‐independent manner has considerable clinical significance. These findings, combined with the limited toxicity of 2‐ME, may have significant implications for alternative treatment of advanced prostate cancer. © 2001 Wiley‐Liss, Inc.
Piecewise quadratic approximation of the non‐dominated set for bi‐criteria programs
Authors: Wiecek Margaret M. , Chen Wei , Zhang Jinhuan
Published: August 2002

A procedure to approximate the non‐dominated set for general (continuous) bi‐criteria programs is proposed. The piecewise approximation is composed of quadratic curves, each of which is developed locally in a neighbourhood of a non‐dominated point of interest and based on primal–dual relationships associated with the weighted Tchebycheff scalarization of the original problem. The approximating quadratic functions, in which decision maker's preferences are represented, give a closed‐form description of the non‐dominated set. A numerical example is included. Copyright © 2001 John Wiley & Sons, Ltd.
The extent, motivation, and effect of tying in franchise contracts
Authors: Michael Steven C
Published: August 2002

Tying in franchise contracts has been the subject of considerable antitrust litigation and theoretical analysis. Tying can enhance efficiency by increasing standardization and reducing monitoring costs, or it can be used with market power for price discrimination. In this paper, I report on the extent of tying among restaurant franchisors and test whether it is motivated by efficiency or market power considerations. The results show that the use of tying is not affected by market share or outlet share in various industry sectors, but it is affected by equipment required and by business strategy. The results are weakly supportive of efficiency and not supportive of market power. Copyright © 2000 John Wiley & Sons, Ltd.
Myoclonic status epilepticus: Video presentation
Authors: Badhwar Aman , Siren Auli , Andermann Eva , Andermann Frederick
Published: August 2002

A young woman with juvenile myoclonic epilepsy had recurrent attacks of myoclonic status epilepticus related to a long history of limited compliance and irregular sleep. The diagnosis of this clinical pattern is based mainly on clinical description. A home video captured an attack. © 2002 Movement Disorder Society.
Do unilateral ablative lesions of the subthalamic nucleu in parkinsonian patients lead to hemiballism?
Authors: Barlas Orhan , Hanağası Haşmet A. , İmer Murat , Şahin Hüseyin A. , Sencer Serra , Emre Murat
Published: August 2002

We report the safety results in nine patients with advanced idiopathic Parkinson's disease (PD) who underwent ablative surgery of unilateral subthalamic nucleus (STN). In eight patients, surgical objectives were attained without induction of abnormal involuntary movements or other adverse effects. One patient developed transient hemiballistic movements which improved within 2 weeks after surgery. Assessment at 2 weeks to 20 months postoperatively revealed no long‐term adverse effects. We conclude that hemiballism following unilateral ablation of STN in patients with PD is a rare phenomenon, and unilateral ablative lesions of STN can be performed safely. © 2001 Movement Disorder Society.
Cardiovascular reflex testing contributes to clinical evaluation and differential diagnosis of Parkinsonian syndromes
Authors: Holmberg Björn , Kallio Mika , Johnels Bo , Elam Mikael
Published: August 2002

The differentiation between Parkinson's disease (PD), progressive supranuclear palsy (PSP), and multiple system atrophy (MSA) may be difficult but is important for prognostic and therapeutic purposes. Varying degrees of autonomic failure have been described in PD and MSA, whereas its involvement in PSP remains controversial. The aim of this study was to investigate autonomic function in patients fulfilling strict clinical diagnostic criteria for the disorders above, to evaluate the diagnostic capacity of laboratory autonomic tests. The study group was consecutively recruited among patients referred to a movement disorder unit. Thirty‐four patients with PD, 15 patients with PSP, and 47 patients with MSA were compared with 18 healthy age‐matched controls. Autonomic tests included analysis of heart rate variability (HRV) in temporal domain, at rest and during forced respiration, as well as blood pressure (BP) changes during 75° head‐up tilt.

HRV did not differ between groups during quiet breathing but was significantly reduced during forced respiration in MSA (P < 0.01), while PD and PSP groups did not differ from controls. Hypotensive responses during orthostatic provocation were seen in PD (P < 0.01) and MSA (P < 0.001), whereas BP remained stable in most PSP patients, not differing from the healthy control group. On an individual basis, decreased HRV and severe hypotensive responses were seen in MSA patients regardless of age and disease duration, whereas PD patients showed this combination only at high age and long duration. In PSP, only a few cases with decreased HRV and limited hypotensive responses were found. We conclude that cardiovascular reflex tests can supplement the clinical differentiation of Parkinsonian syndromes. © 2001 Movement Disorder Society.
Persistent chorea triggered by hyperglycemic crisis in diabetics
Authors: Ahlskog J. Eric , Nishino Hiroshi , Evidente V.G.H. , Tulloch John W. , Forbes Glenn S. , Caviness John N. , Gwinn‐Hardy Katrina A.
Published: August 2002

Five female patients developed chorea concurrent with, or shortly after a hyperglycemic episode (admission glucose values 500–1,000 mg/dL). In four of these five patients, there was no prior history of diabetes mellitus. The chorea continued despite correction of blood glucose and persisted to the time of last follow‐up, 6 months to 5 years later. The chorea developed subacutely over 2 days to 1 month and was generalized in one, unilateral in three, and involved right > left lower extremity in the other; the severity initially reached ballistic proportions in two. Associated clinical features were nil in four of these patients, but cognitive impairment and personality change occurred in one. The histories and laboratory studies identified no predisposing factors other than the hyperglycemia. The chorea was sufficiently troublesome to require administration of neuroleptic medication in all five cases. Four of the five cases had high signal intensity within basal ganglia on T1‐weighted magnetic resonance (MR) imaging, as has previously been described; however, this was not seen in one case (who had the most severe clinical condition). Most previously described cases have involved a reversible clinical syndrome, in contrast to our patients. The pathogenic mechanisms remain uncertain. © 2001 Movement Disorder Society.
Single‐stage defect repair with latissimus dorsi free flap after extensive resection of terebrant ulcer of the head: Three case reports
Authors: Koeppe Tobias , Kuipers Thomas , Haug Martin , Greulich Michael , Gubisch Wolfgang
Published: August 2002

Three cases of advanced ulcerating basal cell carcinoma (terebrant ulcer or ulcus terebrans) of the head are reported. Neglected basaliomas had deeply destroyed larger parts of the skull in three women ages 78, 69, and 65 years when the patients were first admitted for treatment. Death due to meningitis, hemorrhage, or brain damage was imminent. Wide resection and coverage by free latissimus dorsi flaps was carried out in single‐stage procedures. The latissimus dorsi, a versatile and very reliable free flap with its constant vascular anatomy and long pedicle, is the ideal flap for the coverage of large defects on the head. The donor site can usually be closed primarily, and the functional deficit is acceptable. All three patients recovered completely. Although only palliative resection could be achieved, the procedures could be justified by the increased survival time and gain in quality of life. © 2001 Wiley‐Liss, Inc. MICROSURGERY 21:333–339 2001
Cortical vein end‐to‐end anastomosis after removal of a parasagittal meningioma
Authors: Menovsky Tomas , De Vries Joost
Published: August 2002

A simple technique is described that facilitates a proper procedure of venous end‐to‐end anastomosis during neurosurgical procedures. This technique, which consists of insertion of a Venflon tube in the vein during anastomosis, results in easier handling and proper apposition of the vein, resulting in an improved quality of the anastomosis. The technique was successfully applied in a patient after parasagittal meningioma resection, and the patency of the cortical vein was confirmed postoperatively on magnetic resonance venography. © 2002 John Wiley & Sons, Inc. MICROSURGERY 22:27–29, 2002 DOI 10.1002/micr.22005
Non‐linear stability in the Bénard problem for a double‐diffusive mixture in a porous medium
Authors: Lombardo S. , Mulone G. , Straughan B.
Published: August 2002

The linear and non‐linear stability of a horizontal layer of a binary fluid mixture in a porous medium heated and salted from below is studied, in the Oberbeck–Boussinesq–Darcy scheme, through the Lyapunov direct method. This is an interesting geophysical case because the salt gradient is stabilizing while heating from below provides a destabilizing effect. The competing effects make an instability analysis difficult. Unconditional non‐linear exponential stability is found in the case where the normalized porosity ϵ is equal to one. For other values of ϵ a conditional stability theorem is proved. In both cases we demonstrate the optimum result that the linear and non‐linear critical stability parameters are the same whenever the Principle of Exchange of Stabilities holds. Copyright © 2001 John Wiley & Sons, Ltd.
Image reconstruction of a three‐dimensional dielectric object using a gradient‐based optimization
Authors: Harada Haruyuki , Tanaka Mitsuru , Takenaka Takashi
Published: August 2002

This paper presents an efficient reconstruction algorithm for three‐dimensional scattering objects. The algorithm is an extension of previous work for the two‐dimensional one, and is based on an optimization procedure. From the computer simulations, the proposed method is shown to yield satisfactory results, and to not be so sensitive to the presence of noise. © 2001 John Wiley & Sons, Inc. Microwave Opt Technol Lett 29: 332–336, 2001.
An experimental study on electromagnetic inverse scattering of a perfectly conducting cylinder by using the real‐coded genetic algorithm
Authors: Qing Anyong
Published: August 2002

Electromagnetic inverse scattering of a perfectly conducting cylinder with real data by using the real‐coded genetic algorithm is presented in this paper. The cylinder is denoted by a local shape function with respect to its local origin. The inverse problem is to locate the cylinder, and to reconstruct its shape given the measured scattered electric field. To guarantee the nonnegative definiteness of the local shape function, it is approximated as cubic B‐splines with N control points instead of a trigonometric series of order N/2. The local origin and the control points are the optimization parameters for the real‐coded genetic algorithm. They are searched in a very wide space. A sample rectangular cylinder which is center located or decenter located is reconstructed. The reconstruction results confirm the strong search ability and the robustness of the real‐coded genetic algorithm. © 2001 John Wiley & Sons, Inc. Microwave Opt Technol Lett 30: 315–320, 2001.
Body composition of long‐term survivors of acute lymphoblastic leukaemia†
Authors: Warner Justin T. , Evans William D. , Webb David K.H. , Gregory John W.
Published: August 2002

Background

Long‐term quality of life is of growing importance in children previously treated for malignancy. Obesity defined indirectly from indices of height and weight, has been described in long‐term survivors of acute lymphoblastic leukaemia (ALL) and hypothesised to be a consequence of previous cranial irradiation.

Procedure

In this study, measures of whole and regional body composition using skinfold and dual energy X‐ray absorptiometry (DEXA) measurements have been made in 35 long‐term survivors of ALL who had received cranial irradiation and chemotherapy. To assess the influence of cranial irradiation, results were compared with those obtained in 21 children treated for other malignancies, who received chemotherapy alone and with 31 healthy sibling controls.

Results

Girls treated for ALL were significantly fatter than those treated for other malignancies or healthy control siblings whether measured by skinfold thickness (median (range) 37.4% (17.9–41.3) vs. 24.6% (19.1–35.0) and 28.8% (19.6–43.1), respectively, P < 0.01) or DEXA (33.5% (20.5–42.8) vs. 25.5% (16.5–31.0) and 24.5% (18.8–53.6), respectively, P < 0.01). Boys treated for ALL were not significantly fatter than boys in the other two groups. Measures of whole body percent fat derived from DEXA were persistently less than those derived from skinfold measurements with a mean (95% CI) difference of 2.4% (1.7–3.1, P < 0.001) for all groups combined. In ALL survivors, using regression equations for skinfold thicknesses derived from controls with DEXA as the ‘gold standard’ method, fat mass was significantly overestimated.

Conclusion

Female survivors of ALL are significantly fatter than those of other malignancies and healthy sibling controls. Caution should be observed in the application of published equations, derived from the normal population, for the calculation of body composition in children treated for ALL. The mechanism of onset of obesity remains unclear, but is probably multifactorial and related to previous cranial irradiation. Med Pediatr Oncol 2002;38:165–172. © 2002 Wiley‐Liss, Inc.
NMR analysis of novel ganglioside GM4 analogues containing de‐N‐acetyl and lactamized sialic acid: probes for searching new ligand structures for human L‐selectin
Authors: Hamada Toshiyuki , Hirota Hiroshi , Yokoyama Shigeyuki , Otsubo Nobumasa , Ishida Hideharu , Kiso Makoto , Kanamori Akiko , Kannagi Reiji
Published: August 2002

Detailed analysis of the 1H and 13C NMR spectra of two novel ganglioside GM4 analogues de‐N‐acetyl sialyl GM4 (1) and cyclic sialyl GM4 (2), which contain de‐N‐acetyl and lactamized sialic acid, respectively, instead of the usual N‐acetylneuraminic acid, was carried out. The combination of NMR data, such as cyclization shifts, coupling pattern, intraresidual NOEs and the appearance of NH proton, provided the 5, 2B conformation for 2. Moreover, the conformation of a glycosidic bond connecting the Neu and Gal residues was determined by some interresidual NOEs in both 1 and 2. Copyright © 2002 John Wiley & Sons, Ltd.
Non‐empirical calculations of NMR indirect carbon–carbon coupling constants: 1. Three‐membered rings
Authors: Krivdin Leonid B. , Sauer Stephan P. A. , Peralta Juan E. , Contreras Rubén H.
Published: August 2002

The carbon–carbon indirect nuclear spin–spin coupling constants in cyclopropane, aziridine and oxirane were investigated by means of ab initio calculations at the RPA, SOPPA and DFT/B3LYP levels. We found that the carbon–carbon couplings are by far dominated by the Fermi contact term. Our best SOPPA and DFT results are in a very good agreement with each other and with the experimental values, whereas calculations at the RPA level of theory strongly overestimate the carbon–carbon couplings. Significant differences in the basis set dependence of the calculated carbon–carbon coupling constants obtained with either wavefunction method, RPA or SOPPA, or the density functional method, DFT/B3LYP, are observed. The SOPPA results depend much more strongly on the quality of the basis set than the results of DFT/B3LYP calculations. The medium‐sized core‐valence basis sets cc‐pCVTZ and even cc‐pCVDZ were found to perform fairly well at the SOPPA level for the one‐bond carbon–carbon couplings investigated here. Copyright © 2002 John Wiley & Sons, Ltd.
Golgi matrix protein gene, Golga3/Mea2, rearranged and re‐expressed in pachytene spermatocytes restores spermatogenesis in the mouse
Authors: Banu Yasmin , Matsuda Miyuki , Yoshihara Mitsuyo , Kondo Masaaki , Sutou Sizuyo , Matsukuma Shoichi
Published: August 2002

In a transgenic mouse, Golga3/Mea2 gene (human homolog: GOLGA3/golgin‐160) was disrupted by a translocation at the site of the transgene integration. Exons 8–24 of the disrupted gene remained intact and formed a fusion gene (ΔMea2) with the antisense strand of E. coli‐derived transgene by means of a cryptic splice signal in there. The protein product of ΔMea2, virtually a form truncated to 2/3 of the normal size, localized to Golgi apparatus of pachytene spermatocytes and round spermatids. ΔMea2 expression was specific to the testis, but varied among separate seminiferous tubules. It also showed variation among homozygous individuals from 0.5 to 4.3% of the wild type (wt) level. At the lowest levels, neither spermatids nor spermatozoa were present in the homozygous testes, but when the expression of ΔMea2 increased to 4.3% of the wt level, high sperm production was restored and a sporadic (1/22) fertile homozygous male was obtained. The earliest apoptotic degeneration of pachytene spermatocytes evidenced at 17 dpp in homozygous testes in some discrete seminiferous tubules was preceded by ΔMea2 expression in a variegated fashion at 16 dpp. These results consistently indicated that in homozygous testes, the pachytene spermatocytes which failed to express ΔMea2 may undergo apoptotic degeneration. Golga3/Mea2, and ΔMea2 in homozygotes, in a certain excessive amount may be important for survival of pachytene spermatocytes in the mouse. Mol. Reprod. Dev. 61: 288–301, 2002. © 2002 Wiley‐Liss, Inc.
Altered levels of mRNA expression and pharmacological reactivity of α1‐adrenergic receptor subtypes in the late‐pregnant rat myometrium
Authors: Ducza Eszter , Gáspár Róbert , Falkay George
Published: August 2002

The adrenergic system plays a major role in the regulation of the uterine contractility during pregnancy. Our previous studies have shown the significance of the α1‐adrenergic receptors (ARs) in the control of pregnant uterine contractility both in vitro and in vivo. Our present aim was to determine the changes in mRNA expression and pharmacological reactivity of the α1‐ARs on days 18, 20, and 22 of pregnancy. To demonstrate the expressions of α1‐AR subtype mRNA, we used a reverse transcription‐polymerase chain reaction (RT‐PCR); the pharmacological reactivity was tested by electric field stimulation (EFS). The expression of α1A‐AR mRNA increased from day 18 to 22, while no α1B‐AR mRNA was detectable. We found a small increase in the expression of α1D‐AR mRNA on day 20, which was not followed by a significant change in pharmacological reactivity. The α1D‐receptor expression and pharmacological reactivity decreased significantly up to day 22. EFS studies revealed that the α1A‐AR antagonist 5‐methylurapidil had EC50 values (1.9 × 10−6–6.3 × 10−6 M) about one order of magnitude lower than those of the α1D‐AR antagonist BMY 7378 (4 × 10−6–3.6 × 10−5 M). However, the α1B‐AR antagonist cyclazosine exerted only a slight effect on the stimulated contractions. Strong correlations were found between the α1A‐mRNA expression and the EC50 of 5‐methylurapidil (r2 =0.9712), and between the α1D‐AR mRNA expression and the EC50 of BMY 7378 (r2 = 0.9937). Our findings suggest that both α1A‐ and α1D‐ARs are involved in the regulation of the pregnant uterine contractility. The density and pharmacological reactivity indicate that the α1A‐AR seems to play the major role in late‐pregnant myometrial contraction. Mol. Reprod. Dev. 62: 343–347, 2002. © 2002 Wiley‐Liss, Inc.
Testicular protein Spag5 has similarity to mitotic spindle protein Deepest and binds outer dense fiber protein Odf1
Authors: Shao Xueping , Xue Jiaping , van der Hoorn Frans A.
Published: August 2002

Outer dense fibers (ODF) and the fibrous sheath (FS) are major cytoskeletal structures in the mammalian sperm tail. The molecular mechanisms underlying their morphogenesis along the axoneme or their function are poorly understood. Recently, we reported the cloning and characterization of Odf2, a major ODF protein, and Spag4, an axoneme‐binding protein, by virtue of their strong interaction with Odf1, the 27 kDa major ODF protein. We proposed a crucial role for leucine zippers in molecular interactions during sperm tail morphogenesis. Here we report the cloning and characterization of a novel gene, Spag5, which encodes a 200 kDa testicular protein that interacts strongly with Odf1. Spag5 is transcribed and translated in pachytene spermatocytes and spermatids. It bears 73% similarity with the mitotic spindle protein Deepest of unknown function. We identified two putative leucine zippers in the C‐terminal part of the Spag5 protein, the downstream one of which is involved in interaction with Odf1. Interestingly, these motifs are present in Deepest. These results highlight the importance of the leucine zipper in sperm tail protein interactions. Mol. Reprod. Dev. 59: 410–416, 2001. © 2001 Wiley‐Liss, Inc.
Fiber‐optic stethoscope: A cardiac monitoring and gating system for magnetic resonance microscopy
Authors: Brau Anja C.S. , Wheeler Charles T. , Hedlund Laurence W. , Johnson G. Allan
Published: August 2002

A fundamental problem associated with using the conventional electrocardiograph (ECG) to monitor a subject's cardiac activity during magnetic resonance imaging (MRI) is the distortion of the ECG due to electromagnetic interference. This problem is particularly pronounced in MR microscopy (MRI of small animals at microscopic resolutions (< 0.03 mm3)) because the strong, rapidly‐switching magnetic field gradients induce artifacts in the animal's ECG that often mimic electrophysiologic activity, impairing the use of the ECG for cardiac monitoring and gating purposes. The fiber‐optic stethoscope system offers a novel approach to measuring cardiac activity that, unlike the ECG, is immune to electromagnetic effects. The fiber‐optic stethoscope is perorally inserted into the esophagus of small animals to optically detect pulsatile compression of the esophageal wall. The optical system is shown to provide a robust cardiac monitoring and gating signal in rats and mice during routine cardiac MR microscopy. Magn Reson Med 47:314–321, 2002. © 2002 Wiley‐Liss, Inc.
Multislice first‐pass cardiac perfusion MRI: Validation in a model of myocardial infarction†
Authors: Epstein Frederick H. , London James F. , Peters Dana C. , Goncalves Lino M. , Agyeman Kwabena , Taylor Joni , Balaban Robert S. , Arai Andrew E.
Published: August 2002

The purpose of this study was to validate a first‐pass MRI method for imaging myocardial perfusion with multislice coverage and relatively small analyzable regions of interest (ROIs). A fast gradient‐echo (FGRE) sequence with an echo‐train (ET) readout was used to achieve multislice coverage, and a high dose of a contrast agent (CA) was used to achieve a high signal‐to‐noise ratio (SNR). Dogs (N = 6) were studied 1 day after reperfused myocardial infarction, and fluorescent microspheres were used as a standard for perfusion. First‐pass MRI correlated well vs. microsphere flow, achieving mean R values of 0.87 (range = 0.82–0.93), 0.71 (range = 0.46–0.85), and 0.72 (range = 0.49–0.95) for subendocardial ROIs, transmural ROIs, and the endocardial‐epicardial ratio, respectively. Additionally, analysis of myocardial time‐intensity curves (TICs) indicated that 15.8 ± 6.6° sectors, corresponding to 260 μl of endocardium, can be analyzed (R2 > 0.95). Magn Reson Med 47:482–491, 2002. Published 2002 Wiley‐Liss, Inc.
MRI of muscular fat
Authors: Schick Fritz , Machann Jürgen , Brechtel Klaus , Strempfer Andrea , Klumpp Bernhard , Stein Daniel T. , Jacob Stephan
Published: August 2002

An MRI technique with high selectivity and sensitivity to the signal components in the chemical shift range of methylene and methyl protons of fatty acids has been developed for noninvasive assessment of muscular fat in vivo. A spoiled gradient‐echo sequence with spatial‐spectral excitation by six equidistant pulses with 2°‐(−9°)‐17°‐(−17°)‐9°‐(−2°) and a multi‐echo train (TE = 16, 36, 56, 76, 96, and 116 ms) allowed a series of images to be recorded with a receiver bandwidth of 78 Hz per pixel. SIs from phantoms with lipid contents between 0.1% and 100% were compared to those from pure water. Thirty healthy volunteers underwent fat‐selective imaging of their lower leg, and parallel localized proton spectroscopy of the tibialis anterior and the soleus muscle by a single‐voxel stimulated echo acquisition mode (STEAM) technique (TR = 2 s, TE = 10 ms, TM = 15 ms). Results show a high correlation (r = 0.91) between fat imaging and the spectroscopic approach in the soleus muscle, considering the percentage total fat content of musculature. The correlation coefficient was clearly lower (r = 0.55) in the tibialis anterior muscle due to signal contaminations from adjacent subcutaneous fat in the images, inhomogeneous fat distribution, and generally lower lipid content in this muscle. Applications of the new imaging technique showed marked intra‐ and interindividual variability in the spatial distribution of lipids in the musculature of the lower leg. No significant correlation of the muscular fat with the thickness of the subcutaneous fat layer was found. In addition, the body mass index does not appear to determine muscular fat content, except in very obese cases. Magn Reson Med 47:720–727, 2002. © 2002 Wiley‐Liss, Inc.
Lactate discrimination incorporated into echo‐planar spectroscopic imaging
Authors: Bito Yoshitaka , Ebisu Toshihiko , Hirata Satoshi , Takegami Tetsuro , Yamamoto Yukari , Tanaka Chuzo , Naruse Shoji
Published: August 2002

A technique for discriminating a lactate signal from overlapping lipid signals in 1H spectroscopic imaging is presented. It is based on J‐coupling between lactate protons and on the broad spectral bandwidth of lipid signal. Measurement parameters used in the technique are determined so that TE is separated from n/J (n: a natural number, J: J‐coupling constant) enough to suppress the lipid signal at the time when the lactate signal is strongest. Data processing is used to calculate the lactate signal intensity from the reconstructed spectra. This technique enables lactate to be discriminated in a single measurement and enables spectra of other metabolites to be acquired simultaneously. However, it necessitates a homogeneous magnetic field, long TE, and supplementary lipid suppression. Discrimination of the lactate signal is demonstrated by applying lactate‐discriminating echo‐planar spectroscopic imaging (EPSI), which combines this discrimination technique with the standard EPSI, to rat focal cerebral ischemia models. Magn Reson Med 45:568–574, 2001. © 2001 Wiley‐Liss, Inc.
MR microscopy of cobalt‐labeled nerve cells and pathways in an invertebrate brain (Sepia officinalis, Cephalopoda)
Authors: Quast Michael J. , Neumeister Heike , Ezell Edward L. , Budelmann Bernd U.
Published: August 2002

This article describes a novel application of contrast‐enhanced MR microscopy to trace nerve cells and pathways through small invertebrate brains. Using the cuttlefish Sepia officinalis (Cephalopoda) as a model, the cells and pathways of one of the brain nerves were labeled with paramagnetic cobalt(II) ions by conventional centripetal cobalt iontophoresis. In MR microscopy, the cobalt‐labeled cell bodies and pathways became hypointense in 9.4 T spin echo images. Their course and distribution were identical with those seen with conventional histological techniques after cobalt sulphide precipitation (with or without subsequent silver intensification). Magn Reson Med 45:575–579, 2001. © 2001 Wiley‐Liss, Inc.
High‐sensitivity single‐shot perfusion‐weighted fMRI†
Authors: Duyn Jeff H. , Tan Charlene X. , Gelderen Peter van , Yongbi Martin N.
Published: August 2002

A method is presented for measurement of perfusion changes during brain activation using a single‐shot pulsed spin labeling technique. By employing a double‐inversion labeling strategy, stationary tissue (background) signal was suppressed while minimally affecting perfusion sensitivity. This allowed omission of the otherwise required reference scan, resulting in twofold‐improved temporal resolution. The method was applied to visual and motor cortex activation studies in humans, and compared to standard FAIR‐type perfusion labeling techniques. Experiments performed at 1.5T and 3.0T indicate a close to 90% suppression of background signal, at a cost of an 11% and 9%, respectively, reduction in perfusion signal. Combined with the twofold increase in signal averaging, and a reduction in background signal fluctuations, this resulted in a 64% (1.5T, N = 3) and a 128% (3T, N = 4) overall improvement in sensitivity for the detection of activation‐related perfusion changes. Magn Reson Med 46:88–94, 2001. Published 2001 Wiley‐Liss, Inc.
Chronic eosinophilic perimyositis with persistent myalgias
Authors: Zivkovic Sasa A. , Lacomis David , Clemens Paula R.
Published: August 2002

A 43‐year‐old man with an 8‐year history of hypereosinophilia was evaluated for persistent muscle pain. Methotrexate and corticosteroids were ineffective. Examination, limited by pain even with passive motion, showed only mild weakness. Electromyography and muscle enzymes were normal. A needle muscle biopsy specimen revealed eosinophilic perimyositis. This case illustrates that the diagnosis of eosinophilic perimyositis requires histopathological evaluation, which should be pursued in patients with eosinophilia and persistent myalgia despite normal electromyography and muscle enzymes. © 2002 Wiley Periodicals, Inc. Muscle Nerve 25: 000–000, 2002
Correlation between nerve conduction studies and clinical scores in diabetic neuropathy
Authors: Feki Imed , Lefaucheur Jean‐Pascal
Published: August 2002

Polyneuropathy, a frequent complication of diabetes, can be assessed clinically and electrophysiologically. Neurological examination can be quantified by validated scores, e.g., the neuropathy symptom score (NSS) or the neuropathy disability score (NDS). Such scores exclude electrophysiological aspects of the neuropathy. A software tool was designed to convert electrophysiological data into one single index of polyneuropathy (IPN). This index was calibrated to grade the severity of a polyneuropathy from 0.00 to 1.00. In a series of 38 diabetic patients, we have calculated NSS, NDS, and IPN. We found correlations between these variables, NDS and IPN exhibiting the more significant association. The use of IPN allowed us to demonstrate that nerve conduction values correlated with clinical scores in diabetic polyneuropathy. Such a software tool, by providing a single electrophysiological index, may facilitate clinico‐electrophysiological assessment in large descriptive studies or therapeutic trials of diabetic polyneuropathy. © 2001 John Wiley & Sons, Inc. Muscle Nerve 24:555–558, 2001
Urinary collagen metabolite excretion in amyotrophic lateral sclerosis
Authors: Ono Seiitsu , Shimizu Natsue , Imai Takashi , Rodriguez Gladys P.
Published: August 2002

Collagen abnormalities of the spinal cord and the skin have been reported in patients with amyotrophic lateral sclerosis (ALS). The urinary concentrations of the hydroxylysine glycosides, i.e., glucosylgalactosyl hydroxylysine (glu‐gal Hyl) and galactosyl hydroxylysine (gal Hyl), indicate the tissue origin of the collagen metabolites and the rate of the degradation of collagen. We measured the urinary levels of glu‐gal Hyl and gal Hyl in 12 ALS patients, 10 diseased control subjects with other neurologic or muscular diseases (Control Group A), and 10 healthy control subjects (Control Group B). The urinary level of glu‐gal Hyl in ALS patients was significantly lower than in the two control groups. In addition, a significant negative relationship between glu‐gal Hyl urinary level and duration of illness was found in ALS patients. There was no marked difference in the urinary level of gal Hyl between ALS patients and the control groups. Our data suggest that the decreased urinary level of glu‐gal Hyl may be useful in assessing the alteration in collagen metabolism in ALS and may have a relationship with the progression of ALS. © 2001 John Wiley & Sons, Inc. Muscle Nerve 24: 821–825, 2001
Incomplete recovery of voluntary isometric force after fatigue is not affected by old age
Authors: Allman Brian L. , Rice Charles L.
Published: August 2002

The 60‐min recovery profiles of voluntary and electrically stimulated force, contractile speed, surface electromyography, muscle activation via twitch interpolation, and muscle compound action potentials (M‐waves) in the elbow flexors of seven young men (24 ± 2 years) and seven men over 80 years of age (84 ± 2 years) were compared following intermittent (3 s on, 2 s off) contractions at 60% of each subject's maximum voluntary contraction (MVC) force. There was no age‐related difference between groups in the average time to fatigue or the rate of voluntary force loss; both groups lost 40% of their force within approximately 5 min. Despite a rapid increase to ∼83% of the prefatigue MVC by the third minute of recovery for both groups, MVC force did not return to the prefatigue value within 60 min (94 ± 4% young, 91 ± 3% old). These results suggest that the incomplete recovery of voluntary force was likely due to a peripheral limitation in the muscle at the level of excitation–contraction coupling, and was not affected by age. Delayed recovery of voluntary force and a greater degree of low‐frequency fatigue in the old men were not observed and there were no age‐related impairments in any parameter normalized to the prefatigue value during fatigue or recovery. We suggest that the specific fatigue task may be more important to recovery than proposed alterations in the aged neuromuscular system when normalization and matching of the fatigue task criteria occurs. © 2001 John Wiley & Sons, Inc. Muscle Nerve 24: 1156–1167, 2001
Disparate dysfunction of skeletal muscles located near and distant from burn site in the rat
Authors: Ibebunjo Chikwendu , Martyn Jeevendra
Published: August 2002

This study tested the hypotheses that burn‐induced change in muscle function varies at sites local and distant from burn and is related to changes in expression of acetylcholine receptors (AChRs) and muscle mass. In anesthetized rats, ∼4% burn was inflicted over the tibialis anterior muscle of one limb. The contralateral leg served as control. In another study, a ∼45% body surface area burn was produced on the trunk; controls were body sham‐burned rats. The evoked twitch tensions of tibialis anterior muscles in both legs were measured together with AChR proteins and their transcripts. Compared with the contralateral leg, absolute tensions in the burned leg declined at days 1, 4, and 7 without loss of muscle mass so that tension per unit wet muscle mass (specific tension) decreased; at day 14, the tension decreased with muscle atrophy so that specific tension was unchanged. Membrane AChRs and/or the immature subunit transcript, AChRγ messenger ribonucleic acid (mRNA) increased at days 4, 7, and 14, and both were inversely related to evoked tension (r = .43, P < .01 and r = .61, P < .0001, respectively). There was a direct correlation between AChR and AChRγ mRNA (r = .82, P < .001), suggesting that the upregulated AChRs may contain the immature γ‐subunit isoform. After ∼45% body burn, AChRs and mRNA did not change and the evoked tensions did not decline, but there was relative loss of muscle mass at days 7 and 14 so that specific tension increased. Burn trauma initially causes weakness of muscles directly under the burn, and this weakness may be partially related to increased expression of immature AChRs and later to muscle atrophy. © 2001 John Wiley & Sons, Inc. Muscle Nerve 24: 1283–1294, 2001
Gentle dorsal root retraction and dissection can cause areflexia: Implications for intraoperative monitoring during “selective” partial dorsal rhizotomy
Authors: Logigian Eric L. , Soriano Sulpicio G. , Herrmann David N. , Madsen Joseph R.
Published: August 2002

During partial dorsal rhizotomy (PDR), intraoperative dorsal rootlet stimulation often evokes nonreflex, rather than reflex, motor responses that are due to costimulation of adjacent ventral roots. Intraoperative areflexia typically predicts that motor responses evoked by dorsal rootlet stimulation are nonreflexive. The cause of areflexia during PDR is in part due to anesthesia, but other mechanisms are likely to play a role as well. In this study of three consecutive patients undergoing lumbosacral neurosurgery, soleus H‐reflexes evoked by tibial nerve stimulation at the popliteal fossa were found to suddenly decline in amplitude following retraction and gentle dissection of the S‐1 dorsal root. In one areflexic patient, dorsal rootlet stimulation proximal to the main site of dissection evoked soleus H‐reflexes, although they could not be evoked by tibial nerve stimulation. We conclude that the gentle retraction and dissection of dorsal rootlets that occurs during PDR can induce conduction block of reflex afferents. High‐intensity dorsal rootlet stimulation distal to the site of conduction block may then evoke not reflex responses, but rather nonreflex motor responses, due to the costimulation of adjacent ventral roots. © 2001 John Wiley & Sons, Inc. Muscle Nerve 24: 1352–1358, 2001
Nerve conduction abnormalities in aging mice deficient for myelin‐associated glycoprotein
Authors: Weiss Michael D. , Luciano Carlos A. , Quarles Richard H.
Published: August 2002

Ultrastructural, biochemical, and electrophysiological analyses were done on 12–14‐month‐old mice deficient for myelin‐associated glycoprotein (MAG) to further characterize the neuropathy that develops as they age. Electron microscopy demonstrated normal myelin compaction and axonal degeneration in a large number of myelinated nerve fibers. Western blots showed that the proteins of compact myelin, P0 glycoprotein, and myelin basic protein were not significantly altered in the mutants; however, the Schwann cell protein, 2′,3′‐cyclic nucleotide 3′‐phosphodiesterase, was reduced to less than half the control level. Also, both total and phosphorylated high‐molecular‐weight neurofilament proteins (TNFH and PNFH, respectively) were significantly decreased, as was the PNFH:TNFH ratio. Electrophysiological evaluation revealed a mild, but statistically significant, reduction of conduction velocity and a nonsignificant mild decrease in compound muscle action potential amplitudes. This constellation of findings in aging MAG‐null mice is consistent with an axonopathy that resembles axonal Charcot–Marie–Tooth (CMT2) disease in many respects. Thus, mutation of a myelin‐associated gene expressed by Schwann cells can induce axonal degeneration and cause a neuropathy with minimal signs of demyelination. © 2001 John Wiley & Sons, Inc. Muscle Nerve 24: 1380–1387, 2001
Patterns of muscle involvement in inclusion body myositis: Clinical and magnetic resonance imaging study
Authors: Phillips Beverley A. , Cala Leslie A. , Thickbroom Gary W. , Melsom Alison , Zilko Paul J. , Mastaglia Frank L.
Published: August 2002

The differential patterns of muscle involvement in the upper and lower limbs in sporadic inclusion body myositis (sIBM) were examined in 18 patients using both quantitative and manual muscle testing as well as magnetic resonance imaging (MRI) in 9 patients. Weakness of the quadriceps femoris and the forearm flexors was present in most patients, but there was considerable variability in the patterns and severity of muscle involvement. MRI disclosed preferential patterns of muscle involvement within functional groups such as the quadriceps femoris, in which there was severe involvement of the vasti with relative sparing of the rectus femoris, and the triceps surae, in which selective involvement of the medial gastrocnemius was common. Involvement of flexor digitorum profundus on MRI was found in only one third of patients. The results emphasize the variability in the clinical phenotype and differential susceptibility of muscles to the disease process in sIBM. © 2001 John Wiley & Sons, Inc. Muscle Nerve 24: 1526–1534, 2001
A comprehensive model of spastic hypertonia derived from the pendulum test of the leg
Authors: Le Cavorzin Philippe , Poudens S. Annick , Chagneau Francis , Carrault Guy , Allain Hervé , Rochcongar Pierre
Published: August 2002

We propose a comprehensive model of spastic hypertonia based on clinical neurophysiology and validated using experimental data obtained from the pendulum test of the leg in 8 healthy volunteers and 15 spastic patients. This nonlinear computational model includes mechanical parameters and a stretch reflex representation involving three neural parameters: a threshold coefficient, the gain of the stretch reflex, and a time lag accounting for the reflex loop latency and the electromechanical coupling delay. Variation of the threshold coefficient alone allowed an overall reproduction of experimental data obtained from spastic and healthy subjects. We propose that this parameter could represent the supraspinal drive, supposed to be preserved in control subjects and decreased in spastic patients. No subsequent variation of the reflex gain was required to simulate spastic traces. Adjustment of the time lag influenced the duration of the swinging phase and oscillatory phenomena possibly occurring during the pendulum test. It could be related to the involvement of either short‐ or long‐latency stretch reflex loops. With respect to current neurophysiological concepts of motor control, this modeling approach may help in understanding mechanisms underlying spastic hypertonia, and in predicting the clinical effect of antispasticity agents. © 2001 John Wiley & Sons, Inc. Muscle Nerve 24: 1612–1621, 2001
Incrementalization of a single hardening constitutive model for frictional materials
Authors: Lade P. V. , Jakobsen K. P.
Published: August 2002

The governing equations for an elasto‐plastic constitutive model for frictional materials such as soil, rock, and concrete are presented, and the incremental form is indicated in preparation for implementation of the model in a user‐defined module for finite element calculations. This isotropic, work‐hardening and ‐softening model employs a single yield surface, it incorporates non‐associated plastic flow, and its capability of capturing the behaviour of different types of frictional materials under various three‐dimensional conditions has been demonstrated by comparison with measured behaviour, as presented in the literature. The incrementalization procedure is indicated and the resulting equations for the single hardening model are presented together with parameters for a dense sand. Following the implementation of the model, these parameters are used for evaluation of different integration schemes as presented in a companion paper by Jakobsen and Lade (Int. J. Numer. Anal. Meth. Geomech. 2002; 26:661). Copyright © 2002 John Wiley & Sons, Ltd.
Implementation algorithm for a single hardening constitutive model for frictional materials
Authors: Jakobsen K. P. , Lade P. V.
Published: August 2002

An advanced elasto‐plastic constitutive model for frictional materials, whose incremental version is presented in a companion paper (Int. J. Numer. Anal. Meth. Geomech., 2002; 26:647), is implemented in a user‐defined material module. The general calculation strategy inside this module is presented and discussed, including the initial intersection of the yield surface and the techniques for updating of stresses and hardening modulus. Several integration schemes are implemented in the module and their capabilities in relation to the advanced, three‐dimensional constitutive model are evaluated. The forward Euler, modified Euler, and Runge–Kutta–Dormand–Prince integration schemes are explained in detail, compared, and evaluated in view of error tolerances and computational efficiency. Copyright © 2002 John Wiley & Sons, Ltd.
Economic ordering quantities for recoverable item inventory systems
Authors: Teunter Ruud H.
Published: August 2002

We study a deterministic EOQ model of an inventory system with items that can be recovered (repaired/refurbished/remanufactured). We use different holding cost rates for manufactured and recovered items, and include disposal. We derive simple square root EOQ formulas for both the manufacturing batch quantity and the recovery batch quantity.