bluuebunny/crossref_metadata_2025_split huggingface dataset:
Novel heteroplasmic mtDNA mutation in a family with heterogeneous clinical presentations
Authors: Corona P. , Lamantea E. , Greco M. , Carrara F. , Agostino A. , Guidetti D. , Dotti M. T. , Mariotti C. , Zeviani M. 
Published: August 2002

AbstractThe protean manifestations of a novel maternally inherited point mutation of the mitochondrial genome are reported. The proband showed isolated, spastic paraparesis. A brother, who had suffered from a multisystem progressive disorder, ultimately died of cardiomyopathy. Another brother is healthy. The proband's mother showed truncal ataxia, dysarthria, severe hearing loss, mental regression, ptosis, ophthalmoparesis, distal cyclones, and diabetes mellitus. A muscle biopsy performed in the proband failed to show the morphological abnormalities typical of mitochondrial disorders; the activities of respiratory chain complexes were normal. However, complex I and IV activities were low in the muscle homogenate of the affected mother and brother. Sequence analysis of mtDNA showed a heteroplasmic mutation of the tRNAIle gene (G4284A). The mutation load was approximately 55%, 80%, and 90% in the muscle mtDNA of the proband, his mother, and his affected brother, respectively. Mutation was undetected in the healthy brother, as well as in 100 control samples. Several cybrid clones containing homoplasmic mutant mtDNA from the proband showed significant reductions of complex IV activity and maximum oxygen consumption rate, compared with homoplasmic wild‐type clones derived from the same subject.
Destruction of neurons by cytotoxic T cells: A new pathogenic mechanism in rasmussen's encephalitis
Authors: Bien Christian G. , Bauer Jan , Deckwerth Thomas L. , Wiendl Heinz , Deckert Martina , Wiestler Otmar D. , Schramm Johannes , Elger Christian E. , Lassmann Hans 
Published: August 2002

AbstractRasmussen's encephalitis is a progressive epileptic disorder characterized by unihemispheric lymphocytic infiltrates, microglial nodules, and neuronal loss leading to the destruction of the affected hemisphere. In this study, immunohistochemical evaluation of specimens from 11 patients revealed lymphocytic infiltrates that consisted mainly of CD3+CD8+ T cells. Of these cells, 7.0% lay in direct apposition to MHC class I+ neurons. Confocal laser microscopy revealed that these lymphocytes contained granzyme B in a polar orientation toward these perikarya. Single neurons underwent apoptosis. These findings indicate that a T‐cell–mediated cytotoxic reaction induces neuronal death in Rasmussen's encephalitis. This study directly shows, for what we believe is the first time, that a cytotoxic T‐cell mechanism contributes to loss of neurons in human brain disease.
Antibody‐mediated suppression of Vβ5.2/5.3+ T cells in multiple sclerosis: Results from an MRI‐monitored phase II clinical trial
Authors: Killestein Joep , Olsson Tomas , Wallström Erik , Svenningsson Anders , Khademi Mohsen , Blumhardt Lance D. , Fagius Jan , Hillert Jan , Landtblom Anne‐Marie , Edenius Charlotte , Årfors Leopold , Barkhof Frederik , Polman Chris H. 
Published: August 2002

AbstractThe objective of this study was to evaluate the safety and efficacy of the humanized antibody ATM‐027 in a baseline versus treatment magnetic resonance imaging‐monitored study. Expansion of Vβ5.2/5.3+ T cells has been demonstrated in the peripheral blood, cerebrospinal fluid, and brain lesions of MS patients. In a phase I study, ATM‐027 depleted these cells in peripheral blood and, in parallel, T‐cell MBP reactivity and IFN‐γ expression were reduced. We studied 59 patients with relapsing‐remitting MS (47 on ATM‐027 and 12 on placebo) stratified for HLA‐DR2 status. Monthly intravenous injections were given for 6 months. Individual dose titration was employed to obtain depletion of the target T‐cell level and downregulation of antigen receptor density as monitored by flow cytometry. Five monthly magnetic resonance imaging scans were performed before treatment to establish baseline activity, six during treatment, and three during follow‐up. Additional immunological assessments were performed to elucidate the mechanism of action of ATM‐027. The treatment was safe and well tolerated, inducing consistent suppression of the target cell population. During run‐in, active lesions were found in 78.7% (37/47) of patients treated with ATM‐027. During treatment, the median number of lesions was reduced by 33% (p = 0.13) independent of DR2 status. The corresponding volume of enhancement was 221 mm3 at baseline, with a reduction of 10% during treatment. Decreased numbers of cells expressing interferon‐γ messenger RNA, and decreased T‐cell reactivity to several myelin antigens were found in ATM‐027 treated patients. In conclusion, consistent suppression of Vβ 5.2/5.3+ T cells was achieved. However, the effect size on magnetic resonance imaging was considerably less than the targeted 60%.
Age‐related disability in multiple sclerosis
Authors: Trojano Maria , Liguori Maria , Bosco Zimatore Giovanni , Bugarini Roberto , Avolio Carlo , Paolicelli Damiano , Giuliani Fabrizio , De Robertis Francesca , Marrosu Maria Giovanna , Livrea Paolo 
Published: August 2002

AbstractThere is evidence that the clinical course of multiple sclerosis is age related. The present study evaluated the relationship between age and rate of disability progression in a large hospital‐based cohort of definite cases of multiple sclerosis (n= 1,463). Patients were followed every 6 to 12 months for a total period of observation of 11,387.8 person‐years. Expanded Disability Status Scale scores increased significantly with increasing current age and longer duration of disease (p=0.007). Median times to reach Expanded Disability Status Scale scores of 4.0 and 6.0, assessed using an extended Kaplan–Meier method with age as a categorical time‐varying covariate, were significantly longer among patients aged 20 to 35 years compared with patients aged 36 to 50 and 51 to 65 years (p < 0.0001). Significant associations were observed between mean Expanded Disability Status Scale scores and age at disease onset, current age, and the interaction of age at disease onset and current age (p < 0.001). Current age had a greater effect (59% of variability in the model) on disease severity than did age at disease onset. Furthermore, a multiplicative effect on Expanded Disability Status Scale score was observed for age at disease onset and current age combined, indicating a faster rate of disease progression in older patients. In conclusion, the results of the current study demonstrate the impact of age on rate of disability progression in multiple sclerosis and suggest that an age‐adjusted progression index may be a more relevant criterion for defining differences between multiple sclerosis groups.
Human herpesvirus 6 encephalitis associated with hypersensitivity syndrome
Authors: Fujino Yasuhiro , Nakajima Masashi , Inoue Hirosato , Kusuhara Tomohiko , Yamada Tatsuo 
Published: August 2002

AbstractHypersensitivity syndrome, a serious systematic reaction to a limited number of drugs, is associated with the reactivation of human herpesvirus 6. A 56‐year‐old man developed acute limbic encephalitis followed by multiple organ failure during the course of toxic dermatitis induced by aromatic anticonvulsants. The clinical features of skin eruptions, high fever, eosinophilia, and atypical lymphocytosis were compatible with drug hypersensitivity syndrome. The patient showed seroconversion for human herpesvirus 6, and polymerase chain reaction detected human herpesvirus 6 DNA in the cerebrospinal fluid. To our knowledge, this is the first report of human herpesvirus 6 encephalitis associated with hypersensitivity syndrome.
Relapsed and late‐onset Nipah encephalitis
Authors: Tan Chong Tin , Goh Khean Jin , Wong Kum Thong , Sarji Sazilah Ahmad , Chua Kaw Bing , Chew Nee Kong , Murugasu Paramsothy , Loh Yet Lin , Chong Heng Thay , Tan Kay Sin , Thayaparan Tarmizi , Kumar Shalini , Jusoh Mohd Rani 
Published: August 2002

AbstractAn outbreak of infection with the Nipah virus, a novel paramyxovirus, occurred among pig farmers between September 1998 and June 1999 in Malaysia, involving 265 patients with 105 fatalities. This is a follow‐up study 24 months after the outbreak. Twelve survivors (7.5%) of acute encephalitis had recurrent neurological disease (relapsed encephalitis). Of those who initially had acute nonencephalitic or asymptomatic infection, 10 patients (3.4%) had late‐onset encephalitis. The mean interval between the first neurological episode and the time of initial infection was 8.4 months. Three patients had a second neurological episode. The onset of the relapsed or late‐onset encephalitis was usually acute. Common clinical features were fever, headache, seizures, and focal neurological signs. Four of the 22 relapsed and late‐onset encephalitis patients (18%) died. Magnetic resonance imaging typically showed patchy areas of confluent cortical lesions. Serial single‐photon emission computed tomography showed the evolution of focal hyperperfusion to hypoperfusion in the corresponding areas. Necropsy of 2 patients showed changes of focal encephalitis with positive immunolocalization for Nipah virus antigens but no evidence of perivenous demyelination. We concluded that a unique relapsing and remitting encephalitis or late‐onset encephalitis may result as a complication of persistent Nipah virus infection in the central nervous system.
Low cerebrospinal fluid hypocretin (orexin) and altered energy homeostasis in human narcolepsy
Authors: Nishino Seiji , Ripley Beth , Overeem Sebastiaan , Nevsimalova Sona , Lammers Gert Jan , Vankova Jitka , Okun Michele , Rogers William , Brooks Stephen , Mignot Emmanuel 
Published: August 2002

AbstractHypocretins (orexins) are hypothalamic neuropeptides involved in sleep and energy homeostasis. Hypocretin mutations produce narcolepsy in animal models. In humans, narcolepsy is rarely due to hypocretin mutations, but this system is deficient in the cerebrospinal fluid (CSF) and brain of a small number of patients. A recent study also indicates increased body mass index (BMI) in narcolepsy. The sensitivity of low CSF hypocretin was examined in 38 successive narcolepsy–cataplexy cases [36 human leukocyte antigen (HLA)‐DQB1*0602‐positive] and 34 matched controls (15 controls and 19 neurological patients). BMI and CSF leptin levels were also measured. Hypocretin‐1 was measurable (169 to 376pg/ml) in all controls. Levels were unaffected by freezing/thawing or prolonged storage and did not display any concentration gradient. Hypocretin‐1 was dramatically decreased (<100pg/ml) in 32 of 38 patients (all HLA‐positive). Four patients had normal levels (2 HLA‐negative). Two HLA‐positive patients had high levels (609 and 637pg/ml). CSF leptin and adjusted BMI were significantly higher in patients versus controls. We conclude that the hypocretin ligand is deficient in most cases of human narcolepsy, providing possible diagnostic applications. Increased BMI and leptin indicate altered energy homeostasis. Sleep and energy metabolism are likely to be functionally connected through the hypocretin system.
Unexpected regioselectivity in the palladium‐catalyzed reaction of silacyclobutanes with aryl iodides
Authors: Tanaka Yoshifumi , Nishigaki Atsushi , Kimura Yutaka , Yamashita Masakazu 
Published: August 2002

AbstractThe reaction of aryl iodides with 1,1‐diphenyl‐silacyclobutane in the presence of a catalytic amount of Pd(PPh3)4 affords unexpected ring‐opening adducts, 1‐ and 2‐propenyl(triaryl)‐silanes, in good yields. On the other hand, the PdCl2(PhCN)2‐catalyzed reaction of 1,1‐diphenylsilacyclobutanes with aryl halides gives ­unexpected products, triarylsilanols, after ­hydrolysis in moderate yields. The catalysis involves the reaction of aryl–palladium intermediates with silacyclobutanes along with ­regioselective aryl–silicon bond formation. Copyright © 2001 John Wiley & Sons, Ltd.
Synthesis of Si–C–N coatings by thermal Plasmajet chemical vapour deposition applying liquid precursors
Authors: Wilden Johannes , Wank Andreas , Asmann Marcus , Heberlein Joachim V. R. , Boulos Maher I. , Gitzhofer Francois 
Published: August 2002

AbstractMaterials in the system Si–C–N feature excellent properties for wear protection applications, even at elevated temperatures, and an excellent thermal shock resistance. As these materials have no melting point, coatings have to be manufactured via a synthesis. Conventional chemical vapour deposition (CVD) processes have the disadvantage of low deposition rates. Thermal Plasmajet CVD processes with liquid feedstock feature the highest deposition rates among the gas‐phase synthesis processes. Single and triple DC torches and HF torches with supersonic nozzles have successfully been applied to produce Si–C(–N) coatings on different steel, aluminium, titanium and copper alloys, as well as on graphite. Besides chlorosilanes, hexamethyldisiloxane, tetramethyldisiloxane and hexamethyldisilazane have been used as liquid single precursors. Deposition rates up to 1500 μm h−1 have been achieved. The coatings show cauliflower, columnar or dense morphology and an amorphous or nanocrystalline structure. The formation of both α‐ and β‐Si3N4 has been verified by X‐ray diffraction. The application of chlorosilanes always results in chlorine‐containing coatings. The chlorine causes severe corrosion in the interface to mild carbon steel substrates. The processes are compared taking into account their characteristics concerning the injection modes, gas temperature and velocity profiles determined by enthalpy probe measurements. The process conditions are correlated to the coating microstructure and the adhesion to the substrates and guidelines for the optimum production of ­Si–C–N coatings by Plasmajet CVD are deduced. Emission spectroscopy is used to determine the mechanisms of the coating formation. Full dissociation of the liquid feedstock in the plasma jet has been verified. Copyright © 2001 John Wiley & Sons, Ltd.
Poly‐DL‐lactide–poly(ethylene glycol) microspheres as oral and parenteral delivery systems for hepatitis B surface antigen
Authors: Li Xiaohong , Zhou Shaobing , Wu Xiaorong , Yuan Minglong , Liu Li , Jia Wenxiang , Deng Xianmo , Huang Zhitang 
Published: August 2002

AbstractThis project was aimed at illustrating the potential use of poly‐DL‐lactide–poly(ethylene glycol) (PELA) microspheres as a hepatitis B surface antigen (HBsAg) delivery system following subcutaneous (s.c.) or oral immunization over the current injection of an alum‐absorbed antigen. The antigen‐loading microspheres were elaborated by the solvent‐extraction method based on the formation of modified multiple w/o/w emulsion. The microspheres were characterized by their particle size, HBsAg entrapment, and in vitro HBsAg release behavior. Balb/c mice were immunized with an s.c. injection and oral administration of a single dose and two doses of a microsphere formulation. For comparison, the alum‐absorbed HBsAg‐immunized mice had a following intramuscular (i.m.) injection at weeks 0 and 4. At weeks 8, 10, 14, and 24 postadministration, the blood and saliva samples were collected and detected by the enzyme‐linked immunosorbed assay (ELISA) method. A single injection of HBsAg/PELA microspheres could induce a serum lgG antibody level comparable to the two‐injection alum‐absorbed HBsAg at the 14th week and higher than that at the 24th week. The saliva lgA of peroral groups was significantly higher than that of the s.c. injection of a microsphere formulation and i.m. injection of soluble antigen. These preliminary results demonstrated the potential of oral administration of antigen‐loading microspheres in the induction of a secretory immune response, and it is suggested that a single‐dose s.c. injection of antigen‐loading microspheres would be an efficient immunization schedule to elicit a protective response. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 83: 850–856, 2002
Rheological study of eucalyptus tar pitches
Authors: Prauchner Marcos J. , Pasa Vânya M. D. , Otani Choyu , Otani Satika 
Published: August 2002

AbstractThe development of advanced carbonaceous materials (ACMs) from biopitches is important to increase the revenue of the charcoal making industry and to stimulate the use of biomass, thereby attending to the appeals for environmental preservation. A pioneer study on the rheological behavior of eucalyptus tar pitches was carried out in this work. This behavior plays an important part in obtaining ACMs from pitch, particularly in the spinning step of carbon fiber production. Our results showed that biopitches have a strong dependence on the viscosity and temperature/softening point ratio. An Arrhenius‐type law gave the activation energies for viscous flow. Different from conventional polymers, this energy was higher for more polymerized pitches because of their higher molecular stiffness. The results obtained by the Williams–Landel–Ferry equation showed that the viscosity can be associated with the free volume. Lower viscosities correspond to larger free volume. The plot of the apparent viscosity versus the shear time at constant temperature and shear rate showed that the pitches have a purely viscous flow. Experiments that changed the shear rate showed that biopitches behave as Newtonian fluids. Purely viscous and Newtonian behaviors are desirable for more stable spinning. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 84: 900–908, 2002; DOI 10.1002/app.10096
Melt/solution processable conducting polyaniline: Elastomeric blends with EVA
Authors: Paul Raji K. , Pillai C. K. S. 
Published: August 2002

AbstractPolyaniline (PANI) protonated with dopant, the sulfonic acid of 3‐pentadecylphenoxyacetic acid (SPDPAA; synthesized from an inexpensive naturally existing biomonomer, cardanol), was blended with an elastomeric polymer, the ethylene vinyl acetate (EVA) copolymer. Blending was performed either by emulsion polymerization of aniline into the EVA matrix or by the solution‐mixing method. Thin films were prepared by the conventional melt‐processing technique for an emulsion‐polymerized system and by the solution‐casting method for a solution‐mixed system. In the case of the emulsion‐polymerized system, the percolation threshold occurs at a very low weight percentage of PANI, and a maximum conductivity value of 0.85 S cm−1 was obtained for 28.5 wt % of PANI. These elastomeric conducting blends were characterized by elemental analysis, FTIR and UV‐visible spectral analysis, conductivity measurements, SEM, XRD, tensile properties, TGA, and DSC. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 84: 1438–1447, 2002; DOI 10.1002/app.10408
Controlled destruction of residual crosslinker in a silicone elastomer for drug delivery
Authors: Karlsson Anders , Singh Satish K. , Albertsson Ann‐Christine 
Published: August 2002

AbstractIn drug delivery systems that use silicone elastomers as a diffusion matrix for the active drug, it is common to crosslink the material by the hydrosilylation reaction. In this platinum‐catalyzed reaction, vinyl groups on a polymer add to the methyl siloxane hydride (MHS) groups on a low molecular mass crosslinker. With an excess of crosslinker, a fast curing is achieved and a fully crosslinked material is formed. Unreacted MHS groups were shown to remain in the elastomer after curing because of the excess crosslinker. In this work, a simple procedure was developed to eliminate the unreacted MHS groups from the final product. We found that storage of the product at +40°C and 75% relative humidity for a few weeks will effectively destroy the residual MHS groups in the elastomer. The effects of varying levels of humidity, oxygen, and temperature on this postcuring procedure were studied. The amount of MHS groups was measured with NMR and IR spectroscopy. We also found that the hardness of the material increased by approximately 25% as a consequence of this postcuring treatment. This increase is probably due to a secondary crosslinking reaction between MHS and silanol groups. Heat treatment at higher temperatures led to an even further increase in the hardness and compression modulus. Because no MHS groups remained in the elastomer when this heat treatment was started, it is apparent that another secondary crosslinking reaction is occurring, probably silanol condensation. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 84: 2254–2264, 2002
The diffusion and bulk properties of polyurethane (PU) ‐based hydrophilic and hydrophobic membranes
Authors: Pulat Mehlíka , Akdoğan Ayten 
Published: August 2002

AbstractIn this study, the diffusion characteristics of diclofenac‐Na through hydrophobic and hydrophilic polyurethane (PU)‐based membranes are investigated. Hydrophilic polymers are obtained by graft copolymerization of PU with acriylamide (AAm) and itaconic acid (IA). The membranes are prepared by a solvent‐casting method and characterized by Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM) analysis. The diffusion measurements are performed using a diffusion cell for 10 h at 37°C. Permeability coefficients calculated from diffusion experiments are ∼3 times higher in hydrophilic membranes than hydrophobic PU membranes. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 85: 193–198, 2002
Structural change in mercerized cotton fibers on cellulase treatment
Authors: Haga T. , Takagishi T. 
Published: August 2002

AbstractCotton fibers treated with liquid ammonia and sodium hydroxide were hydrolyzed with crude cellulase. The structural change in the fibers due to the cellulase treatment was examined in relation to the apparent affinity of Congo Red. The cellulose III crystalline structure collapsed and generated intermediate‐molecular‐ordered regions on cellulase treatment. Adsorption of Congo Red occurred on the crystallite surfaces of cellulose II and cellulose III that was transformed from cellulose II. The fiber, the dominant crystallite phase of which was cellulose III that was transformed from cellulose II, had a considerably increased apparent affinity after cellulase treatment. The intermediate structure on the crystallite surface was associated with the adsorption of Congo Red in the cases of cellulose II and cellulose III. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 80: 1675–1680, 2001
Novel method for preparation of carboxylated nitrile rubber–natural rubber blends using bis(diisopropyl)thiophosphoryl polysulfides
Authors: Naskar Nityananda , Debnath Subhas Chandra , Basu Dipak Kumar 
Published: August 2002

AbstractBis(diisopropyl)thiophosphoryl trisulfide (DIPTRI) and bis(diisopropyl)thiophosphoryl tetrasulfide (DIPTET) are successfully used as a novel coupling agent and accelerator, respectively, to covulcanize an elastomer blend comprising polar carboxylated nitrile rubber (XNBR) and nonpolar natural rubber (NR). These compounds are capable of forming a chemical link between these dissimilar rubbers to produce a technologically compatible blend as judged by a swelling experiment. The blend vulcanizates thus produced exhibit enhanced physical properties that can further be improved by adopting the two‐stage vulcanization technique and also by judicious selection of the NR:XNBR ratio. The blend morphology assessed by scanning electron microcroscopy micrographs accounts for significant improvement in the physical properties of the blend vulcanizates, particularly in two‐stage vulcanization. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 80: 1725–1736, 2001