bluuebunny/crossref_metadata_2025 huggingface dataset:
Kinetics and mechanism of the aminolysis of 4‐nitrophenyl and 2,4‐dinitrophenyl 4‐methylphenyl carbonates in aqueous ethanol
Authors: Castro Enrique A. , Andujar Monica , Campodonico Paola , Santos José G.
Published: August 2002

The reactions of 4‐methylphenyl 4‐nitrophenyl carbonate (MPNPC) and 4‐methylphenyl 2,4‐dinitrophenyl carbonate (MPDNPC) with a series of secondary alicyclic amines are subjected to a kinetic investigation in 44 wt% ethanol–water, at 25.0°C, ionic strength 0.2 M (KCl). Under amine excess over the substrate, pseudo‐first‐order rate coefficients (kobs) are obtained. Plots of kobs against [amine] are linear, with kN as slopes. A biphasic Brönsted‐type plot for kN is obtained for the aminolysis of MPNPC, with slopes β1 = 0.2 (high pKa) and β2 = 0.9 (low pKa). This is in accordance with a stepwise mechanism, through a zwitterionic tetrahedral intermediate (T±), and a change in the rate‐determining step, from formation to breakdown of T± as the amine pKa decreases. For the aminolysis of MPDNPC, a slightly curved Brönsted‐type plot for kN is obtained, with β1 = 0.1 (low pKa) and β2 = 0.55 (high pKa). This is consistent with a concerted mechanism. © 2002 Wiley Periodicals, Inc. Int J Chem Kinet 34: 309–315, 2002
Strategic community management promoted by innovation communities
Authors: Kodama Mitsuru
Published: August 2002

For the last few years, the videoconferencing system and multi‐point connection service market represented by multimedia technology have enjoyed strong growth in Japan. Behind the recent upturn in this market was the strategic alliance of NTT, Japan's largest telecommunications carrier, and PictureTel of the USA, followed by the birth of business communities centered around or outside NTT, thus intensively creating and boosting a new market referred to as interactive video communication. This paper reviews the challenges that faced NTT, one of the big businesses in Japan, followed by PictureTel and other players within and outside NTT, all of which created various strategic business communities. Copyright © 2001 John Wiley & Sons, Ltd.
Photomechanical transdermal delivery: The effect of laser confinement
Authors: Lee Shun , McAuliffe Daniel J. , Flotte Thomas J. , Kollias Nikiforos , Doukas Apostolos G.
Published: August 2002

Background and Objective

Photomechanical waves can transiently permeabilize the stratum corneum and facilitate the delivery of drugs into the epidermis and dermis. The present study was undertaken to assess the effect of pulse characteristics to the penetration depth of macromolecules delivered into the skin.

Study Design/Materials and Methods

Photomechanical waves were generated by confined ablation with a Q‐switched ruby laser. Fluorescence microscopy of frozen biopsies was used to assay the delivery of macromolecules through the stratum corneum and determine the depth of penetration.

Results

Photomechanical waves generated by confined ablation of the target have a longer rise time and duration than those generated by direct ablation. Confined ablation required a lower radiant exposure (from ∼7 J/cm2 to ∼5 J/cm2) for an increase in the depth of delivery (from ∼50μm to ∼400μm).

Conclusions

Control of the characteristics of the photomechanical waves is important for transdermal delivery as they can affect the depth of drug penetration into the dermis. Lasers Surg. Med. 28:344–347, 2001. © 2001 Wiley‐Liss, Inc.
Monitoring 2‐D gel‐induced modifications of proteins by MALDI‐TOF mass spectrometry
Authors: Hamdan Mahmoud , Galvani Marina , Righetti Pier Giorgio
Published: August 2002

I.
Introduction
121

II.
Protein Alkylation by Acrylamide and Its N‐Substituted Monomers
122

III.
Protein Alkylation by Free Immobiline Chemicals
125

IV.
Site of Reaction
127

V.
Probing Protein Unfolding Through the Monitoring of Cys Alkylation
129

VI.
Protein Reactions with a Number of Gel Electrophoresis Crosslinkers
130

VII.
Do Such Modifications Manifest Themselves in Real‐Life Analyses?
134

VIII.
How Does Sample Preparation for 2‐D Gels Influence Certain Modifications?
136

IX.
What Are the Consequences of a Poor Sample Alkylation?
136

X.
Conclusions
138

Acknowledgments
139

References
139

In addition to more than 200 endogenously produced post‐translational modifications, a detailed analysis of 2‐D gel‐separated proteins must also consider other modifications that a protein can experience during various steps of its separation. This review describes the use of matrix‐assisted laser desorption/ionization time‐of‐flight (MALDI‐TOF) mass spectrometry to investigate some of these modifications, which can originate during sample preparation and/or during the separation phase. The analyses described were mostly conducted at pH 9–9.5, and yielded reliable information on stable adduct formation that involved protein‐bound amino acids and a number of gel components, including acrylamide derivatives, gel cross‐linkers, and Immobiline chemicals. The –SH group of Cys was found to be the prime target of such adducts; however, longer reaction times revealed the involvement of the ε‐NH2 of Lys. The same analysis revealed that the failure to achieve full reduction/alkylation prior to any electrophoretic step could result in protein–protein interaction, which could lead to a number of spurious spots in the final 2‐D map. The implications of these modifications on the MS analysis in particular and on proteome research in general are discussed. © 2001 John Wiley & Sons, Inc., Mass Spec Rev 20:121–141, 2001
Protease inhibitor–induced stabilization of p21waf1/cip1 and cell‐cycle arrest in chemical carcinogen–exposed mammary and lung cells†
Authors: Khan Qasim A. , Dipple Anthony , Anderson Lucy M.
Published: August 2002

In previous studies, we have shown that human breast and lung carcinoma cells and mouse nontransformed type II lung cells fail to undergo cell‐cycle arrest in G1 phase in response to treatment with hydrocarbon carcinogens but rather accumulate in the S phase with damaged DNA. This situation may lead to replication of DNA on a damaged template and enhance frequency of mutations. The mechanism of this G1 arrest failure was examined. Western immunoblot analyses of MCF7 human mammary cancer cells exposed to actinomycin D (used as a positive control for G1 cell‐cycle arrest) or hydrocarbon carcinogens revealed that while all of these chemicals caused an increase in p53, only trace levels of p21waf1/cip1 protein were observed in the hydrocarbon carcinogen‐treated samples. Similarly, in murine lung E10 type II cells, p53 but not p21waf1/cip1 protein increased in response to benzo[a]pyrene dihydrodiol epoxide. Treatment of either MCF7 mammary or E10 lung cells with the protease inhibitor calpain I resulted in increased levels of p21waf1/cip1 protein and enhancement of arrest of the cells in early phases of the cell cycle (G1 and early S phase). The results suggest that failure of cell‐cycle arrest in carcinogen‐treated mammary and lung cells is related to increased protease‐mediated degradation of p21waf1/cip1 and/or related regulatory proteins. Published 2002 Wiley‐Liss, Inc.
Inhibitory effect of glycolic acid on ultraviolet‐induced skin tumorigenesis in SKH‐1 hairless mice and its mechanism of action
Authors: Hong Jin Tae , Kim Eun Joung , Ahn Kwang Soo , Jung Kyoung Mi , Yun Yeo Pyo , Park Yong Keun , Lee Sun Hee
Published: August 2002

Glycolic acid, an alpha‐hydroxy acid derived from fruit and milk sugars, has been used commonly as a cosmetic ingredient since it was discovered to have photoprotective and anti‐inflammatory effects and antioxidant effects on ultraviolet (UV)B–irradiated skin. Little is known, however, about the functional role of glycolic acid on UV‐induced skin tumorigenesis. In the present study, we examined the effect of glycolic acid on UV (UVA + UVB)–induced skin tumorigenesis and assessed several significant contributing factors in SKH‐1 hairless mice. Inbred hairless female mice (15 animals/group) were irradiated for 5 d/wk at a total dose of 74.85 J/cm2 UVA and 2.44 J/cm2 UVB for 22 wk. Glycolic acid was applied topically twice a week at a dose of 8 mg/cm2 immediately after UV irradiation. Glycolic acid reduced UV‐induced skin tumor development. The protective effect of glycolic acid was a 20% reduction of skin tumor incidence, a 55% reduction of tumor multiplicity (average number of tumors/mouse), and a 47% decrease in the number of large tumors (larger than 2 mm). Glycolic acid also delayed the first appearance of tumor formation by about 3 wk. The inhibitory effect of glycolic acid on UV‐induced tumor development was accompanied by decreased expression of the following UV‐induced cell‐cycle regulatory proteins: proliferating cell nuclear antigen (PCNA), cyclin D1, cyclin E, and the associated subunits cyclin‐dependent kinase 2 (cdk2) and cdk4. In addition, the expression of p38 kinase, jun N‐terminal kinase (JNK), and mitogen‐activated protein kinase kinase (MEK) also was lower in UV + glycolic acid–treated skin compared with expression in UV‐irradiated skin. Moreover, transcription factors activator protein 1 (AP‐1) and nuclear factor κB (NF‐κB) activation was significantly lower in UV + glycolic acid–treated skin compared with activation in UV‐irradiated skin. These results show that glycolic acid reduced UV‐induced skin tumor development. The decreased expression of the cell‐cycle regulatory proteins PCNA, cyclin D1, cyclin E, cdk2, and cdk4 and the signal mediators JNK, p38 kinase, and MEK may play a significant role in the inhibitory effect of glycolic acid on UV‐induced skin tumor development. In addition, the inhibition of activation of transcription factors AP‐1 and NF‐κB could contribute significantly to the inhibitory effect of glycolic acid. © 2001 Wiley‐Liss, Inc.
Case report of pallido‐pyramidal disease with supplementary motor area involvement
Authors: Pradat Pierre‐François , Dupel‐Pottier Corinne , Lacomblez Lucette , Salachas François , Meininger Vincent , Lacomblez Lucette , Spelle Laurent , Bonnaud Isabelle , Ribeiro Marie Joao , Remy Philippe , Samson Yves
Published: August 2002

An C‐flumazenil positron emission tomography (PET) study in a patient with pallido‐pyramidal disease revealed a marked decrease in benzodiazepine‐receptor density in the precentral gyrus cortex and the mesial frontal cortex. We suggest that, in addition to dysfunction of basal ganglia‐dependent systems, degeneration of the supplementary motor area could also be involved in the patient's bradykinesia. © 2001 Movement Disorder Society.
Focal myopathy as a cause of anterocollis in Parkinsonism
Authors: Lava Neil S. , Factor Stewart A.
Published: August 2002

We present a patient with levodopa‐responsive Parkinsonism who developed disproportionate anterocollis over a period of 4 to 5 weeks. A neurological evaluation, including EMG and muscle biopsy, demonstrated the presence of a focal myopathy typical of the so‐called “dropped head syndrome” or “isolated neck extensor myopathy.” Parkinsonian patients presenting with disproportionate anterocollis should be evaluated for focal myopathy, as this may represent one possible cause.
Nonlinear sensory cortex response to simultaneous tactile stimuli in writer's cramp
Authors: Sanger Terence D. , Pascual‐Leone Alvaro , Tarsy Daniel , Schlaug Gottfried
Published: August 2002

Writer's cramp is a task‐specific dystonia that leads to involuntary hand postures during writing. Abnormalities of sensory processing may play a pathophysiological role in this disorder. Electrophysiology studies in a monkey model of focal dystonia have revealed de‐differentiation of sensory maps and the existence of single cells in hand regions of area 3b with enlarged receptive fields that extend to the surfaces of more than one digit. These changes may lead to abnormal processing of simultaneous sensory inputs. To study abnormal processing of simultaneous sensory information in adult humans with writer's cramp, we used functional magnetic resonance imaging to compare the response in primary sensory cortex with simultaneous tactile stimulation of the index and middle finger, with the response to stimulation of each finger alone. We tested five patients with writer's cramp and seven unaffected (normal) subjects. In the normal subjects, a linear combination of the activation patterns for individual finger stimulation predicts the pattern of activity for combined stimulation with 12% error. In writer's cramp patients, the linear combination predicted the combined stimulation pattern with 30% error. Results indicate a nonlinear interaction between the sensory cortical response to individual finger stimulation in writer's cramp. This altered interaction may contribute to the motor abnormalities. © 2001 Movement Disorder Society
Binding interactions between peptides and proteins of the class II Major Histocompatibility Complex
Authors: McFarland Benjamin J. , Beeson Craig
Published: August 2002

The activation of helper T cells by peptides bound to proteins of the class II Major Histocompatibility Complex (MHC II) is pivotal to the initiation of an immune response. The primary functional requirement imposed on MHC II proteins is the ability to efficiently bind thousands of different peptides. Structurally, this is reflected in a unique architecture of binding interactions. The peptide is bound in an extended conformation within a groove on the membrane distal surface of the protein that is lined with several pockets that can accommodate peptide side‐chains. Conserved MHC II protein residues also form hydrogen bonds along the length of the peptide main‐chain. Here we review recent advances in the study of peptide‐MHC II protein reactions that have led to an enhanced understanding of binding energetics. These results demonstrate that peptide‐MHC II protein complexes achieve high affinity binding from the array of hydrogen bonds that are energetically segregated from the pocket interactions, which can then add to an intrinsic hydrogen bond‐mediated affinity. Thus, MHC II proteins are unlike antibodies, which utilize cooperativity among binding interactions to achieve high affinity and specificity. The significance of these observations is discussed within the context of possible mechanisms for the HLA‐DM protein that regulates peptide presentation in vivo and the design of non‐peptide molecules that can bind MHC II proteins and act as vaccines or immune modulators. © 2002 John Wiley & Sons, Inc. Med Res Rev, 22, No. 2, 168–203, 2002; DOI 10.1002/med.10006
Re‐animation of muscle flaps for improved function in dynamic myoplasty
Authors: Stremel Richard W. , Zonnevijlle Erik D.H.
Published: August 2002

The authors report on a series of experiments designed to produce a skeletal muscle contraction functional for dynamic myoplasties. Conventional stimulation techniques recruit all or most of the muscle fibers simultaneously and with maximal strength. This approach has limitations in free dynamic muscle flap transfers that require the muscle to contract immediately after transfer and before re‐innervation. Sequential stimulation of segments of the transferred muscle provides a means of producing non‐fatiguing contractions of the muscle in the presence or absence of innervation. The muscles studied were the canine gracilis, and all experiments were acute studies in anesthetized animals. Comparison of conventional and sequential segmental neuromuscular stimulation revealed an increase in muscle fatigue resistance and muscle blood flow with the new approach. This approach offers the opportunity for development of physiologically animated tissue and broadening the abilities of reconstructive surgeons in the repair of functional defects. © 2001 Wiley‐Liss, Inc. MICROSURGERY 21:281‐286 2001
Partial differential equations of chemotaxis and angiogenesis
Authors: Sleeman B. D. , Levine H. A.
Published: August 2002

The topic of this paper is concerned with an investigation of the qualitative properties of solutions to the following problem.

Let Ω⊂Rn be a bounded domain with boundary ∂Ω.

We seek solutions P,ω∈Rm+1 of the system

subject to the ‘no‐flux’ boundary condition

where n denotes the inward pointing normal to ∂Ω. To close the system we prescribe the initial conditions

In this system D is a constant diffusion coefficient, P is a population density and ω is a vector of nutrients or chemicals whose dynamics influences the movement of P.

Notice here that the substances ω do not diffuse. If they do then the second equation of (1) is modified to

where d is a positive semi‐definite diagonal matrix. This more general system includes the so‐called Keller–Segel model of Biology ([1] Keller EF, Segel LA. Initiation of slime mold aggregation viewed as an instability. Journal of Theoretical Biology 1970; 26: 339–415). To motivate our study of system (1)–(3) we begin by outlining two themes. One basic to developmental biology and the other from angiogenesis. Copyright © 2001 John Wiley & Sons, Ltd.
Patch antenna size reduction by combining inductive loading and short‐points technique
Authors: Desclos L. , Mahe Y. , Reed S. , Poilasne G. , Toutain S.
Published: August 2002

The present letter concerns the reduction of the size of a patch antenna by combining two techniques. Inserting slots as inductive loading and making some short points in the middle of a patch excited originally in the TM001 mode permits us to obtain an overall reduction of 75%. This enables the development of antennas for several applications, especially in portable communication systems requiring small footprint devices. © 2001 John Wiley & Sons, Inc. Microwave Opt Technol Lett 30: 385–386, 2001.
Multinuclear magnetic resonance study of the structure and tautomerism of azide and iminophosphorane derivatives of chloropyridazines
Authors: Cmoch Piotr
Published: August 2002

Some azido‐ and iminophosphorane derivatives of 3,6‐dichloro‐ and 3,4,5,6‐tetrachloropyridazine were synthesized and studied by means of NMR measurements. Based on multinuclear data (chemical shifts, coupling constants) for compounds containing the azide group, no potentially possible tetrazole–azide equilibrium can be observed, even under acidic conditions. An unusual substitution of a chlorine atom (in position 4) of tetrachloropyridazine in the reaction with hydrazine was demonstrated by NMR measurements of two newly synthesized compounds containing azido‐ and iminophosphorane groups. Using multinuclear magnetic resonance data, the sites of ethylation and protonation of azido‐ and iminophosphorane derivatives of chloropyridazines were established. In the case of the tetrazolopyridazines, ethylation occurs at the N1′ and N2′ atoms, whereas for monocyclic compounds it takes place at the N1 and/or N2 atoms of the pyridazine ring. Preferred sites of protonation are the N1′ atom of the tetrazole ring and the N1 atom of the pyridazine ring. Moreover, the structures of potassium salts of 6‐(3‐cyano‐1‐triazeno)tetrazolo[1,5‐b] pyridazine and its amido derivative were established using NMR data, especially 15N NMR chemical shifts. Copyright © 2002 John Wiley & Sons, Ltd.
An improved DEPT–HMQC sequence for high‐throughput NMR analysis
Authors: Spitzer Timothy , Sefler Andrea M. , Rutkowske Randy
Published: August 2002

Two new pulse sequences are presented for the acquisition of DEPT–HMQC spectra, based on the original experiment of Kessler et al. The new sequences employ modifications intended to make the experiment well suited for high‐throughput acquisition and automated analysis. The sequences use coherence selection with gradients to reduce artifacts and constant‐time evolution to suppress unwanted F1 modulation. In addition, the new sequences require fewer pulses than the original experiment, and perform well even when pulse lengths are slightly mis‐set. Copyright © 2001 John Wiley & Sons, Ltd.
Uterine‐embryonic interaction in pig: Activin, follistatin, and activin receptor II in uterus and embryo during early gestation
Authors: van de Pavert S.A. , Boerjan M.L. , Stroband H.W.J. , Taverne M.A.M. , van den Hurk R.
Published: August 2002

The mRNA expression patterns of activin βA and follistatin in the uterus and embryo, the mRNA expression of the activin receptor II in the embryo, and the localization in the uterus of the immunoreactive activin βA and the receptor II proteins in the uterus were examined at gestation days 7–12 after ovulation in pig. Activin was located predominantly at the mesometrial side of the uterus during all stages of pregnancy studied. Follistatin mRNA was absent in the uterus during these stages, suggesting that activin of uterine origin is not inhibited by intra‐uterine follistatin. The receptor was localized throughout the glandular and luminal epithelium of the uterus. In the embryo, activin was expressed predominantly in the epiblast before unfolding, but after unfolding of the epiblast activin expression shifted to the trophoblast. The expression pattern of follistatin mRNA was contrarily to that of activin, i.e., before unfolding predominantly in the trophoblast (days 8–9), and shifted to the epiblast at day 10. During streak stages, follistatin was detected in the node and primitive streak. Activin receptor II mRNA was first detected at day 8 in the embryoblast. At day 11, it was expressed in trophoblast cells near the epiblast, and in the first ingressing mesoderm cells. During the streak stages, it was expressed predominantly in the trophoblast. The presence of activin and its receptor in uterine epithelium and early embryonic tissues indicate that both embryonic and uterine activin are involved in intra‐uterine processes, such as attachment and early embryonic development. Mol. Reprod. Dev. 59: 390–399, 2001. © 2001 Wiley‐Liss, Inc.
Supporting positive sibling relationships during childhood
Authors: Stoneman Zolinda
Published: August 2002

This paper reviews the research literature focusing on the interpersonal relationships between siblings when one child has a disability. Descriptive findings are presented that compare and contrast sibling warmth and positivity, engagement, and conflict in sibling pairs with and without a child with a disability. The social roles assumed by siblings are examined, as are developmental changes in role relationships. Research on the development of the sibling relationship in the family context is reviewed, as are findings concerning the effects of parent differential attention on the quality of the sibling relationship. MRDD Research Reviews 7:134–142, 2001. © 2001 Wiley‐Liss, Inc.
In vivo GABA editing using a novel doubly selective multiple quantum filter
Authors: Shen Jun , Rothman Douglas L. , Brown Peter
Published: August 2002

A novel multiple quantum filtering method is proposed that uses a doubly selective pulse termed Delays Alternating with Nutations for Tailored Excitation (DANTE) for multiple quantum preparation. This method selectively prepares GABA‐3 and GABA‐4 into a multiple quantum state and suppresses all other resonances at 3.0 ppm in each single scan. Phantom tests demonstrated excellent GABA signal retention and complete suppression of overlapping metabolites. It is shown using numerical simulations that overlapping macromolecules are suppressed because the frequency of the first upfield 2π rotation of the doubly selective DANTE pulse coincides with that of the macromolecules at 1.72 ppm. Excellent suppression of overlapping macromolecules was demonstrated in vivo. Using this method the concentration of GABA in the occipital lobe of healthy volunteers was measured to be 1.21 ± 0.28 μmol/mL (mean ± SD, N = 9). Magn Reson Med 47:447–454, 2002. © 2002 Wiley‐Liss, Inc.
Inverse T2 contrast at 1.5 Tesla between gray matter and white matter in the occipital lobe of normal adult human brain
Authors: Zhou Jinyuan , Golay Xavier , van Zijl Peter C.M. , Silvennoinen M. Johanna , Kauppinen Risto , Pekar James , Kraut Michael
Published: August 2002

T2 of cortical gray matter is generally assumed to be longer than that of white matter. It is shown here that this is not the case in the occipital lobe, but that this effect is often obscured at lower resolution and concealed in standard T2‐weighted images. Using a high‐resolution (1 × 1.3 × 2 mm3) segmented EPI Carr‐Purcell‐Meiboom‐Gill sequence, T2 relaxation times of the brain were measured at 1.5 T for eight healthy adult volunteers. The average T2 values of cortical gray and white matter were found to be 88± 2 and 84± 3 msec in the frontal lobe, 84± 2 and 83± 3 msec in the parietal lobe, and 79± 1 and 87 ± 3 msec in the occipital lobe, respectively. This unexpected occipital T2 contrast between gray and white matter is attributed to regional differences in iron concentration. Magn Reson Med 46:401–406, 2001. © 2001 Wiley‐Liss, Inc.
Obturator neuropathy: Causes and outcome
Authors: Sorenson Eric J. , Chen Joseph J. , Daube Jasper R.
Published: August 2002

To study causes of obturator neuropathy and to correlate them with outcome, we retrospectively studied patients seen at the Mayo Clinic electromyography (EMG) laboratory from 1975 through 1999 with a diagnosis of obturator neuropathy. Twenty‐two patients with obturator neuropathy were identified. The clinical outcome of patients with acute obturator neuropathy treated conservatively was good regardless of etiology or severity. © 2002 Wiley Periodicals, Inc. Muscle Nerve 25: 000–000, 2002
Longitudinal study of functional spinal alpha motor neuron loss in amyotrophic lateral sclerosis
Authors: Arasaki K. , Kato Y. , Hyodo A. , Ushijima R. , Tamaki M.
Published: August 2002

Using a microstimulation technique for obtaining motor unit number estimates (MUNEs) of the hypothenar and extensor digitorum brevis (EDB) muscles, we performed a longitudinal study on the natural course of change in the clinical rating scale (Appel score) and of loss of functional spinal alpha motor neurons in amyotrophic lateral sclerosis. The Appel score increased to about 150% of normal at 12 months after onset, about 225% at 18 months after onset, and about 370% at 24 months after onset. By contrast, MUNEs decreased to about 27% of normal at 12 months after onset, about 12% at 18 months after onset, and about 5% at 24 months after onset. The relative merits of these different approaches in detecting changes in the disease process in its early phase are discussed. © 2002 Wiley Periodicals, Inc. Muscle Nerve 25: 000–000, 2002
The action of Lambert–Eaton myasthenic syndrome immunoglobulin G on cloned human voltage‐gated calcium channels
Authors: Pinto Ashwin , Iwasa Kazuo , Newland Claire , Newsom‐Davis John , Lang Bethan
Published: August 2002

In the Lambert–Eaton myasthenic syndrome (LEMS), immunoglobulin G (IgG) autoantibodies to presynaptic voltage‐gated calcium channels (VGCCs) at the neuromuscular junction lead to a reduction in nerve‐evoked release of neurotransmitter and muscle weakness. We have examined the action of LEMS IgGs on cloned human VGCCs stably expressed in transfected human embryonic kidney (HEK293) cell lines: 10–13 (α1A‐2, α2bδ, β4a) and C2D7 (α1B‐1 , α2bδ, β1b). All LEMS IgGs studied showed surface binding to [125I]‐ω‐CTx‐MVIIC‐labeled VGCCs in the α1A cell line and two of six IgGs showed surface binding to [125I]‐ω‐CTx‐GVIA‐labeled VGCCs in the α1B cell line. We next studied the effect of LEMS IgGs (2 mg/ml) on whole‐cell calcium currents in the α1A and α1B cell lines. Overnight treatment of α1A (10–13) cells with LEMS IgGs led to a significant reduction in peak current density without alteration of the current–voltage relationship or the voltage dependence of steady‐state inactivation. In contrast, LEMS IgGs did not reduce peak current density in the α1B cell line. Overall these data demonstrate the specificity of LEMS IgGs for the α1A cell line and suggest that LEMS IgGs bind to and downregulate VGCCs in this cell line. Although several LEMS IgGs can be shown to bind to the α1B (C2D7) cell line, no functional effects were seen on this channel. © 2002 Wiley Periodicals, Inc. Muscle Nerve 25: 000–000, 2002
Recovery from fatigue in fast and slow single intact skeletal muscle fibers from aging mouse
Authors: González Estela , Delbono Osvaldo
Published: August 2002

In the present work, we studied the recovery from fatigue (RF) of single intact fast‐ and slow‐twitch muscle fibers from young (age 5–7 months) and old (age 22–24 months) mice. To examine whether differences in RF underlie decreases in muscle strength and endurance with aging, we performed in vitro experiments in manually dissected extensor digitorum longus (EDL) and soleus muscle fibers. We measured the recovery of the maximum force every 5 min for a total period of 30 min after inducing fiber fatigue. Fibers were classified, according to the fatigue index, into the following three groups: 0.75–0.99, 0.5–0.74, and <0.5. Although the tetanic tension of EDL and soleus fibers from young and old mice recovered significantly, no statistically significant difference in tension or recovery time was observed between age groups. These data support the concept that the reported decline in muscle force and endurance with aging is not related to changes in RF of individual muscles fibers. © 2001 John Wiley & Sons, Inc. Muscle Nerve 24: 1219–1224
Painful sensory polyneuropathy associated with impaired glucose tolerance
Authors: Singleton J. Robinson , Smith A. Gordon , Bromberg Mark B.
Published: August 2002

We examined records of 121 patients coded as idiopathic polyneuropathy, extracting neuropathy symptoms, electromyographic data, and diagnostic blood work. Of 89 patients screened for glucose handling, 28 demonstrated frank diabetes mellitus. Of the remaining 61 patients, 15 (25%) had impaired glucose tolerance (IGT) by American Diabetes Association criteria (serum glucose 140–200 mg/dl 2 h after a 75‐g glucose load). Excluding those with diabetes mellitus, 35% of patients with neuropathic pain had IGT, more than twice the prevalence found in large, unselected population studies. No other common etiology of polyneuropathy was identified. Two‐hour oral glucose tolerance test results were often abnormal, whereas fasting glucose or hemoglobin A1c was normal. Bias due to referral pattern, body weight, or genetics might affect the comparison of our polyneuropathy cohort with a broader, population‐based control. However, our results corroborate an association between IGT and painful sensory polyneuropathy and link these patients syndromically to the typical painful polyneuropathy of diabetes mellitus. © 2001 John Wiley & Sons, Inc. Muscle Nerve 24: 1225–1228, 2001
The frequency of undiagnosed diabetes and impaired glucose tolerance in patients with idiopathic sensory neuropathy
Authors: Novella Steven P. , Inzucchi Silvio E. , Goldstein Jonathan M.
Published: August 2002

The aim of the study was to determine the frequency of undiagnosed abnormal glucose metabolism in patients with idiopathic sensory neuropathy. Patients were separated into two groups depending on presence or absence of painful symptoms, and an oral glucose tolerance test was performed. Of the 48 patients studied, those with painful symptoms had a higher frequency of abnormal glucose metabolism than literature‐based controls, whereas patients without painful symptoms showed no difference. Comparison of patients with and without painful symptoms had a P‐value of 0.02. The results indicate the need to consider undiagnosed abnormal glucose metabolism in patients with idiopathic sensory neuropathy. © 2001 John Wiley & Sons, Inc. Muscle Nerve 24: 1229–1231, 2001
Latency of compound muscle action potentials of the anal sphincter after magnetic sacral stimulation
Authors: Morren G.L. , Walter S. , Lindehammar H. , Hallböök O. , Sjödahl R.
Published: August 2002

The aim of this study was to present the failure rate and normal values for motor latency of the anal sphincter after magnetic sacral stimulation (LMSS) using a modified recording technique. A bipolar sponge electrode was placed in the anal canal for recording. A ground electrode was placed in the rectum to reduce stimulus artifact. Magnetic stimulation was induced through a twin coil energized by a Maglite‐r25 generator. Two groups were examined: 14 healthy volunteers and 14 patients with a spinal cord injury (SCI) above the conus. Nine of 56 studies (16%) failed. There were no significant differences in latency between right‐ and left‐sided stimulation or between the healthy group and the SCI patients. As described, LMSS measurements are minimally invasive and have a low failure rate. They may be used to test the integrity of the distal motor pathway in patients with bladder or bowel dysfunction who may benefit from continuous electrical sacral root stimulation. © 2001 John Wiley & Sons, Inc. Muscle Nerve 24: 1232–1235, 2001
Subjective and objective incontinence 5 to 10 years after Burch colposuspension
Authors: Kulseng‐Hanssen Sigurd , Berild Grete H.
Published: August 2002

The outcome of incontinence surgery was studied using a questionnaire, a 24‐hour pad test (24hPT), and a stress test (ST). Five to 10 years after a Burch colposuspension, 111 patients were asked to complete the Bristol Female Urinary Tract Symptom Questionnaire (BFLUTS) and to perform a 24hPT and a ST. Eighty‐two patients completed the questionnaire and 71 and 69 patients performed the stress and pad tests, respectively. Seventy‐three percent of the patients did not leak during the ST and 75% of the patients were not leaking during the 24hPT. Seventy‐three percent of the patients stated that they were at least occasionally stress or urge incontinent and 62% stated that they were both stress and urge incontinent. However, only 24% of the stress incontinent and 28% of the urge incontinent patients found their incontinence to be “quite a problem” or “a serious problem.” Patients leaking urine only “occasionally,” “once a week,” leaking “drops,” and finding the leakage to be “a bit of a problem” had median leakage 0g during ST and 24hPT. Patients who reported the leakage to occur “sometimes” “most or all of the time” and who found the leakage to be “a bit, quite, or a serious problem” accounted for 20 to 30% of all patients, as did patients leaking during objective tests. Objective tests revealed leakage to occur less frequently compared with self‐reported leakage. The BFLUTS questionnaire revealed leakage to occur with varying frequency, amount, and bother. Leakage occurring seldom, of small amount and bother may be of minor clinical importance. Neurourol. Urodynam. 21:100–105, 2002. © 2002 Wiley‐Liss, Inc.
Does post‐voiding residual volume get less as mobility improves in a rehabilitation ward for older adults?
Authors: Weatherall Mark
Published: August 2002

Impaired bladder emptying is common in frail older adults. This study tests the hypothesis that more complete bladder emptying is associated with better mobility in a rehabilitation ward for older adults. Consecutive admissions to a rehabilitation ward for older adults were considered for inclusion in the study in the week after admission to the ward. Exclusion criteria were cognitive impairment such that consent could not be obtained, non‐English speaking, or presence of an indwelling urinary catheter. A post‐voiding residual (PVR) bladder volume and Rivermead Mobility Index (RMI) were completed for subjects who gave consent, on a weekly basis until discharge. The BladderScan BVI 3000, Diagnostic Ultrasound, instrument was used. Statistical analysis was by a general linear mixed model. In the study period, 114 people were admitted and 57 approached for consent. Twenty‐four people gave consent. Fifty percent of participants had at least one PVR greater than 100 mL. One person was found to be in urinary retention, with a PVR of greater than 700 mL, and was excluded from further analysis. The PVR increased by 1.2 mL (95% CI − 4.6 to 7) for each unit improvement in the RMI. This study suggests that PVR does not decline with improvement in mobility in older adults receiving inpatient rehabilitation. Neurourol. Urodynam. 21:132–135, 2002. © 2002 Wiley‐Liss, Inc.
Actions of the new antimuscarinic compound lu 25‐109 on isolated human and pig detrusor
Authors: Waldeck K. , Larsson B. , Sandberg B. , Andersson K.‐E.
Published: August 2002

The aim of this study was to evaluate the effects of a novel antimuscarinic agent, Lu 25‐109, a partial M1 receptor agonist, and M2/M3 receptor antagonist in human and pig detrusor to establish its affinity for muscarinic receptors in human detrusor and parotid gland and to compare the results with those obtained with oxybutynin. Effects on the detrusor were determined as regards the ability to inhibit carbachol‐induced contractions and contractions induced by electrical field stimulation (EFS). Radioligand binding studies were performed to assess the ability to displace quinuclidinyl benzilate (3H‐QNB) from muscarinic receptors in the detrusor and parotid gland. Lu 25‐109 produced a concentration‐dependent rightward shift of the concentration‐response curves for carbachol in both human and pig detrusor, the pKb values being 6.2 ± 0.1 (n = 6) and 5.8 ± 0.3 (n = 6). Corresponding values for oxybutynin were 7.9 ± 0.1 (n = 7) and 7.8 ± 0.1 (n = 6). Contractions induced by EFS in human detrusor were almost completely inhibited by 100 μmol/L Lu 25‐109 (84 ± 4%; n = 4). In contrast, EFS‐induced contractions in pig detrusor were less sensitive to Lu 25‐109, resulting in a final inhibition of 32 ± 6% (n = 9) with the highest concentration used (100 μmol/L). This difference in effect between human and pig detrusor was not observed with oxybutynin. Radioligand binding experiments demonstrated a small difference in affinity for Lu 25‐109 in the parotid gland compared with the bladder, the pKi values being 6.2 ± 0.1 versus 6.5 ± 0.1 (n = 4). Corresponding values for oxybutynin were 8.5 ± 0.1 versus 8.2 ± 0.1 (n = 4). The results show that Lu 25‐109 competitively and effectively antagonizes carbachol‐induced contractions and contractions induced by EFS in human detrusor muscle. Even if Lu 25‐109 were less potent than oxybutynin, it has an effect profile that makes it of interest to test its ability to counteract bladder overactivity in humans. Neurourol. Urodynam. 21:92–98, 2002. © 2002 Wiley‐Liss, Inc.
Detection of BOLD changes by means of a frequency‐sensitive trueFISP technique: preliminary results
Authors: Scheffler Klaus , Seifritz Erich , Bilecen Deniz , Venkatesan Ramesh , Hennig Jürgen , Deimling Michael , Haacke E. Mark
Published: August 2002

A new method is introduced to detect magnetic field modulation arising from brain activation‐induced BOLD effects. This approach uses a two‐dimensional high‐bandwidth, high‐resolution conventional gradient‐echo steady‐state imaging sequence known as TrueFISP. The ability to visualize changes in oxygen saturation comes from the fact that the method is sensitive to the local field. As is well known, as the oxygen saturation changes so does the local field associated with the venous blood. We demonstrate that it is possible to visualize not only venous blood with this approach on a macroscopic level for major veins, but also to measure conventional oscillatory like signal changes during activated and resting states. Unfortunately, the method has two major drawbacks. First, a long TR is needed to maximize signal changes and, second, the field must be very well shimmed or numerous experiments need to be run to find the activation, as the signal response is sensitive to the starting frequency in the resting state. Nevertheless, these images can be compared directly with anatomical images collected with the same method without the need for distortion correction. Copyright © 2001 John Wiley & Sons, Ltd.
Phosphorus‐31 MR spectroscopy of normal adult human brain and brain tumours
Authors: Maintz David , Heindel Walter , Kugel Harald , Jaeger Richard , Lackner Klaus J.
Published: August 2002

Localized phosphorus‐31 MR spectra were obtained in vivo in a large series of normal human brain tissue specimens of healthy volunteers (n = 36) and various brain tumours (n = 52). Tumour types examined included grade II and grade III gliomas (n = 15 and n = 1, respectively), glioblastomas (n = 16) and meningeomas (n = 12). An additional eight tumours were analysed during chemo‐ or radiotherapy. Spectra were acquired using a modified ISIS pulse sequence with a repetition time of 3 s. Voxel sizes ranged from 56 to 129 ml. The spectra were evaluated using a least‐square variable projection (VARPRO) fitting procedure in the time domain, which allows semi‐quantitative determination of relative metabolite concentrations.

The measurements in normal cerebrum of healthy volunteers revealed the following results of metabolite signal intensity ratios: pH 7.04 (± 0.01), PCr/α‐ATP 0.51 (± 0.03), Pi/α‐ATP 0.17 (± 0.02), PCr/Pi 2.09 (± 0.12), PDE/α‐ATP 3.65 (± 0.13) and PME/α‐ATP 0.41 (± 0.04).

Meningiomas showed the most obvious changes when compared with normal brain tissue. They are characterized by an alkaline environment (pH 7.16 ± 0.03; p < 0.005), a decrease in the phosphocreatine peak (p < 0.0001) and significantly decreased phosphodiesters (p < 0.0001).

Glioblastomas also showed alkalization (pH 7.12 ± 0.02; p < 0.001) and a decrease in PDE/α‐NTP (p < 0.05), but no significant changes in PCr/α‐NTP or PCr/Pi. In gliomas with low malignancy, less distinct changes could be detected with slight alkalization (pH 7.09 ± 0.02; p < 0.05) and more than a two‐fold reduction in the PDE/α‐NTP ratio (p < 0.05). The spectra of brain tumours during chemo‐ and radiotherapy indicated clear but inconsistent influence of the therapy. Copyright © 2002 John Wiley & Sons, Ltd.
The center function on trees
Authors: McMorris F. R. , Roberts Fred S. , Wang Chi
Published: August 2002

When (X, d) is a finite metric space and π = (x1, …, xk) ∈ Xk, a central element for π is an element x of X for which max{d (x, xi): i = 1, …, k} is minimum. The function that returns the set of all central elements for any tuple π is called the center function on X. In this article, the center function on finite trees is characterized. © John Wiley & Sons, Inc.
The fates of cells generated at the end of neurogenesis in developing mouse cortex
Authors: Levers Teresa E. , Edgar Julia M. , Price David J.
Published: August 2002

Most cerebral cortical neurons are generated between embryonic days 11 and 17 (E11–17) in the mouse. Radial glial cells also proliferate during this time; they can give rise to neurons and many later transform into astrocytes. It is thought that most glial cells comprising the mature cortex, including additional astrocytes, are generated after neurogenesis is complete. Little is known about the cellular events that occur during the transition from the phase dominated by neurogenesis to that of gliogenesis. We labeled cells generated on E18 and E19 and the day of birth (P0) with bromodeoxyuridine and followed their fates over the following 20 days. Our results showed that, on E18–P0, cells divide throughout the ventricular zone, subventricular zone, intermediate zone, and to a lesser extent, the developing cortical plate, whereas neuronal precursors generated prior to E18 divide in the ventricular zone. Our results indicated that 30–40% of cells dividing on E18 give rise to neurons that migrate to the most superficial part of the cortex. The rest of the cells dividing on E18 and 76–94% of cells generated on E19 and P0 express the QKI RNA‐binding protein, indicating that they either remain as multipotential progenitors or develop into glial cells. Nine to fifteen percent of cells generated on E18–P0 become glial fibrillary acidic protein‐positive astrocytes. Many E19 and P0 labeled cells disappear between 2 and 20 days postlabeling, probably because they continue to divide. We conclude that the population of cells produced at the end of cortical neurogenesis is heterogeneous and comprises postmitotic neurons, glia (including astrocytes), and possibly multipotential progenitors. © 2001 John Wiley & Sons, Inc. J Neurobiol 48: 265–277, 2001
Transneuronal tracing from sympathectomized lumbar epaxial muscle in female rats
Authors: Daniels Derek , Miselis Richard R. , Flanagan‐Cato Loretta M.
Published: August 2002

Pseudorabies virus (PRV) has been used as a transneuronal tracer to study central neural networks, including the central control of the lordosis‐producing, lumbar epaxial muscles. Within muscles, however, the sympathetic innervation of blood vessels poses a confounding source of tracer labeling in the CNS. The present study destroyed sympathetic nerves before injection of PRV, thereby allowing for a more selective uptake by somatic motoneurons. Specifically, a focal sympathectomy was created by the injection of dopamine‐β‐hydroxylase immunotoxin (DHIT). When PRV was injected into control rats, both somatic motoneurons within the ventral horn of the spinal cord and sympathetic preganglionic neurons within the intermediolateral column (IML) of the spinal cord became labeled. Additionally, labeled neurons were observed in many brain regions, including those previously implicated in the control of the lordosis reflex (e.g., the medullary reticular formation; MRF) and those previously implicated in the control of vasomotor tone (e.g., the rostral ventrolateral medulla; RVLM). When injected into DHIT‐pretreated animals, PRV labeling in ventral horn neurons persisted in many animals; however, labeling in IML was eliminated in almost every case. In these animals, PRV labeling was absent in brain areas traditionally associated with vasomotor tone, such as RVLM, whereas labeling persisted in brain areas previously implicated in the control of the lordosis response, such as MRF. The results support the connectivity of spinal and medullary structures with the somatic control of the lordosis‐producing muscles and provide a more detailed description of these portions of the putative lordosis‐relevant neurocircuitry. © 2001 John Wiley & Sons, Inc. J Neurobiol 48: 278–290, 2001
Membrane formation mechanism and permeation properties of a novel porous polyimide membrane
Authors: Shimizu Hideyuki , Kawakami Hiroyoshi , Nagaoka Shoji
Published: August 2002

The transport properties of a novel porous fluorinated polyimide membrane fabricated by a wet phase inversion process were studied with a stirred dead‐end filtration cell. The porous membrane‐forming solvents were tetrahydrofuran (THF), acetone, N,N‐dimethylacetamide (DMAc), N‐methylpyrrolidone (NMP), N,N‐dimethylformamide (DMF), and dimethylsulfoxide (DMSO). The phase separation phenomena in a ternary system of polyimide/solvent/water were investigated from cloud point curves by a titration method and binary interaction parameters. Solvent–water demixing in the system has been found to play very important roles in determining the structure and surface morphology of the polyimide membrane. The porous fluorinated polyimide membranes showed pore sizes from 4 to 500 nm and permeation properties from ultrafiltration to a microfiltration range. In this study, we particularly focused on fouling of the polyimide membranes, because fouling decreases the flux and increases the resistance. Interestingly, the porous polyimide membrane showed excellent water flux recovery after water cleaning compared with that of the polyethersulfone (PSf) membrane, which suggest that for a 6FDA‐6FAP membrane, the protein–membrane and protein–protein interaction was not so strong compared with those in a PSf membrane. Copyright © 2002 John Wiley & Sons, Ltd.