bluuebunny/crossref_metadata_2025_split huggingface dataset:
Open three‐dimensional unhindered molecular chains: Partition function
Authors: Alvarez‐Estrada Ramón F. 
Published: April 2003

AbstractAn open molecular chain, formed by N classical particles moving in three dimensions and having N − 1 bonds of constant lengths between successive neighbours, is considered. Hamiltonian methods with manifest rotational invariance allow to characterize all constraints. The classical partition function, Z0, for a large open chain in thermal equilibrium is analyzed in general. Simpler integral representations for Z0 are obtained, with the following advantages: (i) explicit rotational invariance in the integrands, (ii) only tridiagonal matrices appear and, moreover, approximations for their determinants can be obtained. For a two‐dimensional open chain, an approximate factorized formula for Z0 is presented, and its essentials are generalized to the three‐dimensional case. In both cases, the features of the partition functions bear certain similarities to that for a classical ideal gas. The approximate partition functions lead to approximate analytical computations of the correlations between pairs of different bond vectors, of the squared end‐to‐end distance, of the probability distribution for the end‐to‐end vector and of the structure factor, which display some novel features. Some comparisons with the corresponding results for the Gaussian chain are made.
Congenital myopathies at their molecular dawning
Authors: Goebel Hans H. 
Published: April 2003

AbstractThe introduction and application of molecular techniques have commenced to influence and alter the nosology of congenital myopathies. Long‐known entities such as nemaline myopathies, core diseases, and desmin‐related myopathies have now been found to be caused by unequivocal mutations. Several of these mutations and their genes have been identified by analyzing aggregates of proteins within muscle fibers as a morphological hallmark as in desminopathy and actinopathy, the latter a subtype among the nemaline myopathies. Immunohistochemistry has played a crucial role in recognizing this new group of protein aggregate myopathies within the spectrum of congenital myopathies. It is to be expected that other congenital myopathies marked by inclusion bodies may turn out to be such protein aggregate myopathies, depending on analysis of individual proteins within these protein aggregates and their association with putative gene mutations. Muscle Nerve 27: 527–548, 2003
Rituximab in the treatment of polyneuropathy associated with anti‐MAG antibodies
Authors: Renaud Susanne , Gregor Michael , Fuhr Peter , Lorenz Delia , Deuschl Günther , Gratwohl Alois , Steck Andreas J. 
Published: April 2003

AbstractNo causative or curative therapy exists for the polyneuropathy associated with antibodies to myelin‐associated glycoprotein (anti‐MAG). Rituximab is a mouse‐human chimeric antibody that specifically eliminates B‐cells and B‐cell precursors. Preliminary results suggest a beneficial effect on antibody‐dependent autoimmune diseases. Nine patients with an anti‐MAG–associated IgM polyneuropathy received rituximab once weekly for 4 weeks. In all patients, the number of B‐cells in the peripheral blood declined below levels of detection, and the IgM levels decreased between 35% and 82% (median, 58%). In eight patients, lowering of the anti‐MAG antibody titers of more than 52% was observed. Clinical status improved in six patients, remained stable in two, and worsened in one. The motor nerve conduction velocity improved by at least 10% in one ulnar nerve in seven patients and worsened in two. Rituximab was well tolerated and is a promising new drug in the treatment of patients with anti‐MAG–associated polyneuropathy. Muscle Nerve 27:611–615, 2003
S‐protein is expressed in necrotic fibers in Duchenne muscular dystrophy and polymyositis
Authors: Louboutin Jean‐Pierre , Navenot Jean‐Marc , Rouger Karl , Blanchard Dominique 
Published: April 2003

AbstractComplement regulatory proteins (CD55, CD59) and a fluid‐phase complement regulator (S‐protein) expression and distribution were studied in Duchenne muscular dystrophy (DMD) and polymyositis by Western blots and immunocytochemistry. In muscle samples from control subjects, no specific signal was detected for CD55 or S‐protein, and CD59 was present on the sarcolemma of the muscle fibers. In DMD and polymyositis, Western blots demonstrated a 18–20 kDa band corresponding to CD59, as well as a signal corresponding to S‐protein. Immunocytochemistry showed a colocalization between complement membrane attack complex (MAC), a molecule previously demonstrated in necrotic muscle fibers in DMD and polymyositis, and S‐protein in necrotic fibers of DMD and polymyositis. Necrotic muscle fibers were more numerous in muscle biopsies of DMD patients with stronger signals for S‐protein in Western blots. These results suggest that S‐protein is not able to prevent the full assembly of MAC in necrotic fibers of patients with DMD and polymyositis, but might instead inactivate MAC deposits present inside necrotic fibers or participate in the clearance of MAC‐attacked muscle fibers. Muscle Nerve 27: 575–581, 2003
Is quantitation necessary for assessment of sural nerve biopsies?
Authors: Pamphlett Roger , Sjarif Adrian 
Published: April 2003

AbstractIn this study we measured the reliability and accuracy of visual assessment of certain features of sural nerve pathology. Three raters visually assessed 20 sural nerves over two sessions. Four features were categorized: (1) myelinated fiber (MF) density; (2) size loss of MFs; (3) thinly myelinated axons; and (4) axonal clusters. Intra‐ and interrater reliabilities for the categories were determined. Quantitative data were compared with the visual assessments. Percentage agreements for single raters between the two sessions ranged from 35% to 100% and 9 times out of 12 were ≥70%. Interrater reliability, however, showed a kappa‐value range of 0.03 (poor) to 0.49 (medium). In 85% of cases, visual ratings were within one category of the quantitated MF loss. However, visual categorization was poor compared with quantitation for determining size loss of MFs and myelin thickness. Quantitation needs to be considered to aid peripheral nerve pathologists in the assessment of some of the features of sural nerve biopsy specimens. Muscle Nerve 27: 562–569, 2003
Self‐inflicted tourniquet paralysis mimicking acute demyelinating polyneuropathy
Authors: Storm S. , Weiss M. D. 
Published: April 2003

AbstractTourniquet paralysis is an uncommon complication of surgery, and self‐inflicted tourniquet paralysis has never been documented to our knowledge. We report a patient with bilateral self‐induced tourniquet paralysis of the lower extremities, whose symptoms were initially attributed to an acute demyelinating sensorimotor polyneuropathy based on clinical presentation and electrodiagnostic study. After investigations failed to reveal a cause, he was found to have placed tourniquets on his legs because of a rare obsession with limb amputation known as apotemnophilia. Significant spontaneous partial resolution of clinical symptoms was noted after 6 weeks. Electrophysiologic evidence of segmental demyelination of multiple motor nerves localized to the same region may help to distinguish this condition from other forms of acute demyelinating polyneuropathy. Muscle Nerve 27: 631–635
, 2003
Intravesical electrical stimulation in the treatment of micturition dysfunction in children
Authors: Gladh Gunilla , Mattsson Sven , Lindström Sivert 
Published: April 2003

AbstractAimsTo evaluate the results of intravesical electrical stimulation (IVES) in an open prospective study to treat underactive detrusor in children. The treatment was offered as an alternative to clean intermittent catheterization (CIC).MethodsForty‐four children were included, 21 girls and 3 boys (6–16 years, md 10) with idiopathic, 9 girls and 11 boys (4–18 years; md 13) with neurogenic underactive detrusor. IVES was given by a catheter electrode in the bladder (cathode) with the anode attached to the suprapubic abdominal skin. Continuous stimulation at 20 or 25 Hz was delivered by battery powered stimulators giving unipolar square‐wave pulses (0,2 or 0,7 ms). Stimulation intensity was adjusted individually according to the acceptance of the child (12–64 mA). IVES was initially given at the clinic but 18 children had additional treatment at home. Effect of treatment was monitored by micturiton/incontinence diary, reports of bladder sensation, recordings of urinary flow, residual volume and frequency of urinary tract infections.ResultsThe IVES‐treatment was completed by 39/44 children. Long term normalization of the voiding (md 2,5 years follow up) was obtained for 20/24 children with idiopathic problems (83%) and 8/20 with neurogenic problems (40%). Another four had much improved bladder function. The neurogenic group required more stimulation sessions than the idiopathic group. Of those on CIC, 11/15 who completed IVES could discontinue the catheterization. The frequency of urinary tract infections and incontinence decreased significantly (P < 0.01).ConclusionsIt is concluded that IVES is a promising method to treat the underactive detrusor in children. Neurourol. Urodynam. 22:233–242, 2003. © 2003 Wiley‐Liss, Inc.
Changes in bladder neck geometry and closure pressure after midurethral anchoring suggest a musculoelastic mechanism activates closure
Authors: Petros Peter 
Published: April 2003

AbstractAimsThe aim of this study was to investigate the anatomical origins and clinical significance of cough pressure transmission ratio (CTR) by using virtual‐operation (VO) techniques.MethodsThirty‐four patients underwent perineal ultrasound examination, standard urethral pressure cough testing both with and without unilateral midurethral anchoring (VO), all tests being performed without urethral elevation. In eight patients where there was no change in CTR, a one‐sided fold of suburethral vagina (VO) was taken (pinch test) and the CTR repeated.ResultsAfter midurethral anchoring, maximal urethral pressure increased from a mean of 33.25 cm H2O to a mean of 58.06 cm H2O (P < 0.0001) and restoration of anatomy was noted in all 11 patients who had obvious funneling on straining. Conversion of a <100% CTR to >100% CTR in the proximal urethra was observed in 14 of 22 patients (P < 0.005), with no significant change noted in the distal urethra. Further conversion of CTR was noted in six of the remaining eight patients with unilateral plication of suburethral vagina (pinch test).ConclusionsA musculoelastic closure mechanism most likely activates urethral closure. CTR is most likely an index of changed intraurethral area, not necessarily closure, and may be a more sensitive objective test than perineal ultrasound for diagnosing urethral narrowing, especially when used with virtual‐operation techniques. Neurourol. Urodynam. 22:191–197, 2003. © 2003 Wiley‐Liss, Inc.
Bladder pressure monitoring during intermittent catheterization: A comparison of gauges and methods
Authors: Ferguson Corri L. , Walter James S. , Lucero Yuonne , Wheeler John S. , Damaser Margot S. 
Published: April 2003

AbstractAimsWe previously have investigated a technique for serial bladder pressure measurements in patients with spinal cord injury (SCI) using intermittent catheterization. In the current study, we compared an FDA‐approved digital gauge with the previously studied analog gauge and studied the effects of hydrostatic pressure differences.MethodsEither a digital or an analog pressure gauge was attached to each subject's catheter just before bladder catheterization. Both immediate and stable pressures were recorded. The bladder was then drained until nearly empty and pressure was again recorded (almost empty bladder pressure). Detrusor pressure was estimated as full minus almost empty bladder pressure. Bladder pressures greater than 40 cm H2O were presumed to represent bladder contractions. To investigate the effects of hydrostatic pressure, additional measurements, adjusting the level of the air–urine meniscus, were obtained in three subjects.ResultsRecordings were made from nine SCI subjects using both gauges. Estimates of detrusor pressure, with and without bladder contractions, and associated bladder volumes, were not significantly different between digital and analog gauges. In the absence of bladder contractions, detrusor pressure with the meniscus at the end of the catheter (5 ± 1 cm H2O) was significantly lower than that recorded with no adjustment of the urine meniscus (12 ± 1 cm H2O).ConclusionsStandardizing measurement techniques to equalize hydrostatic pressures should facilitate reliable estimates of detrusor pressure. Frequent monitoring of bladder pressure using this technique may assist with the urological care of SCI patients. Neurourol. Urodynam. 22:250–254, 2003. Published 2003 Wiley‐Liss, Inc.
Women's knowledge, practises, and intentions regarding correct pelvic floor exercises
Authors: Chiarelli Pauline , Murphy Barbara , Cockburn Jill 
Published: April 2003

AbstractAimAlthough research has demonstrated the efficacy of pelvic floor exercises (PFXs) for the prevention and treatment of female urinary incontinence (FUI), adherence to PFX regimens is commonly poor. There is some evidence that this finding is in part due to a lack of knowledge about how to perform PFXs correctly and misconceptions about the required frequency and duration of PFX regimens.MethodsBy using a sample of 720 postpartum women, this study investigates women's PFX regimens both before and during pregnancy and postpartum.ResultsFindings demonstrated that most women were aware of the required frequency for PFXs (at least every second day): just over half had done them this often during pregnancy and 91% intended to do so postpartum. However, few had done them at this level before pregnancy and less than half knew that PFXs should be carried out indefinitely throughout the lifetime. Moreover, only two thirds were confident that they were doing PFXs correctly.ConclusionThe findings suggest that, despite good knowledge of the required frequency of PFXs, few women practise them regularly over their lifetime, many apparently perceiving PFXs as relevant only to the childbirth years. Implications for health professionals in addressing these gaps in women's knowledge and practises are discussed. Neurourol. Urodynam. 22:246–249, 2003. © 2003 Wiley‐Liss, Inc.
Ionic miscibility enhancement via microion elimination in sulfonated polystyrene/poly(ethyl‐acrylate‐co‐4‐vinyl pyridine) ionomer blends
Authors: Zhang Xinsheng , Eisenberg Adi 
Published: April 2003

AbstractMiscibility enhancement of ionomer/ionomer and ionomer/polymeric acid systems is studied on the polymer pairs of poly(styrene‐co‐tetramethyl ammonium styrenesulfonate)/poly(ethyl acrylate‐co‐N‐methyl‐4‐vinylpyridinium iodide) and poly(styrene‐co‐styrenesulfonic acid)/poly(ethyl acrylate‐co‐N‐methyl‐4‐vinylpyridinium iodide). NMR and dynamic mechanical results show that in these blends direct macroion–macroion interaction can be achieved with the elimination of microcounterions from the polymer chains. Ion‐ion attraction leads to a miscibility enhancement comparable to that of the previously reported proton transfer blends; a miscible blend is obtained with ca. 5 mol% of ions in the polymers.
High intrinsic conductivity in ladder type polymers: Pyrolyzed BBB
Authors: Davidov D. , Belaish I. , Rettori C. , McLean M. R. , Dalton L. R. 
Published: April 2003

AbstractThrough electrical conductivity and ESR measurements of heat treated BBB‐rigid‐rod ladder polymers, we provide evidence for the existence of an irreversible transformation to another cross‐linked ladder polymer with high intrinsic conductivity. The transformation occurs at a pyrolysis temperature, Tp ≅ 680°C. The results suggest a novel transport mechanism.
Synthesis, polymerization and cation conductive properties of (ω‐carboxy)‐oligo(oxyethylene) methacrylate
Authors: Takeoka Shinji , Maeda Yoshinari , Tsuchida Eishun , Ohno Hiroyuki 
Published: April 2003

AbstractAlkali‐metal salts of (ω‐carboxy)oligo(oxyethylene) methacrylate (CME12M, M = Li or Cs) have been synthesized and polymerized to prepare solid polymer electrolytes. These types of solid polymer electgrolytes provide a homogeneous phase, since these polymers have a flexible main chain, an oligo(oxyethylene) side chain for ion conduction, and a carrier ion source in one repeating unit. The AC conductivity of P(CME12Li) homopolymer is 8.9 × 10−9 S cm−1 at 30°C, while that of P(CME12Cs) is 3.3 × 10−6 S cm−1 at 30°C, which is the highest value among single ion conductors, have been reported as polyelectrolyte “homopolymer” without any additives. High ionic conduction of P(CME12Cs) is due to low glass transition temperature (Tg = −54°C) and weaker ion–ion and ion–dipole interaction of Cs+ than that of Li+.
Phase separation during the chemical blending of polybutadiene/polystyrene blend
Authors: Nam Dong Ki , Kim Sung Chul 
Published: April 2003

AbstractPhase separation behavior of the chemical blending of the polybutadiene (PBD)/polystyrene (PS) was investigated by the light scattering technique. Polybutadiene was dissolved in the styrene monomer and the polymerization of the styrene monomer was carried out thermally in the presence of the dissolved polybutadiene. The effect of the PBD composition, synthesis temperature and the PS crosslink density on the phase separtion behavior were analyzed. The mixture of PBD/PS/styrene monomer showed UCST (upper critical solution temperature) character. It was found that the phase separation was proceeded by the nucleation and growth mechanism in the early stage of polymerization. The time (t) dependence of the domain correlation length (dm) could be represented by a power law in the late stage of the phase separation. The crosslinking of PS hindered phase separation in the coalescence process.
Fluorescence study of polyelectrolyte complex formation I: complexation of anthracene‐loaded poly(methacrylic acid) with polycations
Authors: Itoh Yoshihiro , Negishi Kazuhiko , Lizuka Eisaku , Abe Koji 
Published: April 2003

AbstractPoly(methacrylic acid) containing 0.4 mol% of anthryl groups (PMA‐A) was prepared and its formation of polyelectrolyte complex (PEC) with some polycations in aqueous solution was investigated. The fluorescence intensity of the anthracene (Anth) chromophore increases with the formation of PEC, which may be caused by enhanced hydrophobicity of the microenvironment around the Anth moiety. The intensity depends strongly on the chemical structures and properties of polycations (integral or pendant type, flexibility and hydrophobicity of polymer chains, etc.) and on the experimental conditions (pH and ionic strength).
Ionic conductive polymers based on polymethylsiloxane graft‐crosslinked with oligo(ethylene oxide)
Authors: Mei Henry L. , Okamoto Yoshiyuki , Skotheim Terje 
Published: April 2003

AbstractPolymethylsiloxane graft‐crosslinked with oligo(ethylene oxide) (EO) was synthesized and characterized. The polymer was an elastic solid and stable to hydrolysis. Polymer/salt complexes were formed on mixing with lithium trifluoromethane‐sulfonate(LiCF3SO3). The ionic conductivity of the complexes was measured by complex impedance method and the conductivity reached 6 × 10−5 S cm−1 at 25°C and 1.5 × 10−4 S cm−1 at 40°C. The effect of salt concentration, crosslinking, length of EO units and moisture content on the conductivity were investigated. Glass transition temperature and thermal stability of the polymer and the polymer/salt complexes were determined by differential scanning calorimeter and thermogravimetric analysis measurements.
Water‐soluble polyamides as potential drug carriers, IV: amine‐functionalized copolyaspartamides
Authors: de L. Machado Maria , Neuse Eberhard W. , Perlwitz Axel G. , Schmitt Siegfried 
Published: April 2003

AbstractPoly‐D,L‐succinimide (1) is converted to copolyaspartamides of the general type2by sequential treatment with diamine nucleophiles R′NH2and R″NH2, in which R′ is a group containing a tertiary amine function providing water solubility, and R″ represents a substituent comprising primary or secondary amino groups capable of interaction with suitably carboxyl‐ or carbonyl‐functionalized drug models. The reactions are performed in dimethylformamide medium under mild, yet carefully controlled conditions conducive to aminolytic imide ring opening in the educt polymer without causing crosslink formation through difunctional interaction of the R″NH2co‐nucleophile. The perfectly water‐soluble polymeric products (ηinn, 5–30 ml/g), purified and isolated by dialysis (12,000–14,000 molecular mass cut‐off) and freeze‐drying, are of interest as macromolecular carrier species for pharmaceuticals and other biologically active agents. The drug‐binding potential of the target polymers is demonstrated by the coupling, through active ester intermediacy, of phenylacetic acid as a representative drug model to selected copolyamides.
Solubility of methacrylic acid alkali metal salts in polyethylene oxide and cation conductivity after polymerization
Authors: Ohno Hiroyuki , Ito Yasushi 
Published: April 2003

AbstractMethacrylic acid alkali metal salts (MAAM; M = Li, Na, K, Rb, or Cs) were dissolved in polyethylene oxide, and in situ polymerization was carried out. The solubility of these salt monomers in PEO oligomers increased with the ionic radius of the cation. Their solubility decreased with an increase in the average molecular weight of PEO oligomers, suggesting the considerable contribution of terminal hydroxyl groups of PEO to the solubilization of these salt monomers. The polymerization of MAAM in PEO induced a slight increase of turbidity. The PEO (molecular weight = 200) system containing P(MAAM) shows an ionic conductivity of 1–5 × 10−4 S/cm depending on the cation species. The P(MAAM)/PEO systems having larger cations such as Rb or Cs as the mobile ion show higher ionic conductivity, and a clear relationship was obtained between conductivity and cation radius. This tendency cannot be explained by the ordinary migration model of ions as being either naked or solvated. The fact that the systems having larger cations show higher conductivity can be explained by the following two reasons: the interaction force with the polymer matrix is weaker, and the dissociation energy is lower. The former reason should be dominant, because considerable differences in the ionic conductivity cannot be explained fully by differences in the lattice energy only. Similar experiments were carried out in poly[(oligooxyethylene) methacrylate] (P(MEO)). However, the ionic conductivity of the product remained at around 10−6 S/cm, the observed tendency between the ionic conductivity and the cation radius was quite similar, suggesting the same mechanism as in PEO.
Preparation of photochromic polymers by stereospecific copolymerization of trans‐4‐(2‐methacryloxyethyloxy)azobenzene and (−)‐menthyl methacrylate
Authors: Altomare A. , Ciardelli F. , Lima R. , Solaro R. 
Published: April 2003

AbstractThe synthesis is reported of a new photochromic monomer, trans‐4‐(2‐methacryloxyethyloxy) azobenzene (MEAB), where the azobenzene chromophore is separated from the ester group by an ethylenoxy spacer arm. Comparative experiments show that trans‐4‐methacryloxyazobenzene (MAB), having the azobenzene group directly attached to the ester functionality, does not homopolymerize or copolymerize with (−)‐menthyl methacrylate (MnMA) in the presence of different anionic initiators, whereas isotactic homopolymers and copolymers of MEAB can be obtained: the microstructure is described with reference to analogous atactic macromolecules.