bluuebunny/crossref_metadata_2025_split huggingface dataset:
Does sentinel lymph node biopsy in cutaneous head and neck melanoma alter disease outcome?
Authors: Doting Edwina H. , de Vries Mattijs , Plukker John Th.M. , Jager Piet L. , Post Wendy J. , Suurmeijer Albert J.H. , Hoekstra Harald J. 
Published: May 2006

AbstractBackground and ObjectivesIn the head and neck region, value, reliability, and safety of sentinel lymph node biopsy (SLNB) have not yet been determined conclusively. The aim of study was to assess impact of SLNB on disease outcome in cutaneous head and neck melanoma.MethodsThirty‐six patients with a clinically node‐negative head and neck melanoma, ≥1.0 mm Breslow thickness, participated in a prospective study from 1995 to 2005. Sentinel lymph node (SLN) tumor‐positive patients underwent completion lymphadenectomy. SLN tumor‐negative patients underwent clinical monitoring. Median follow‐up was 54 (range 10–114) months. Recurrence‐free and overall survival curves were constructed by Kaplan–Meier.ResultsSLNs could be identified in 33 patients (92%). In 7 patients (21%) the SLN was tumor‐positive. In 1 patient (13%) the SLNB was false‐negative. In 17 patients (47%) SLNs could be identified in the parotid region (success rate parotid region 100%). This study showed no significant difference in recurrence‐free and overall survival between patients with tumor‐positive and tumor‐negative SLN.ConclusionsThe safety and accuracy of SLNB in the neck and parotid nodal basins were similar to those in non‐head and neck sites. However, the technique is technically demanding in this region. In this small series SLNB did not alter disease outcome. J. Surg. Oncol. 2006;93:564–570. © 2006 Wiley‐Liss, Inc.
Rapid identification of Escherichia coli and Helicobacter pylori in biological samples by capillary zone electrophoresis
Authors: Kłodzińska Ewa , Dahm Hanna , Róźycki Henryk , Szeliga Jacek , Jackowski Marek , Buszewski Bogusław 
Published: May 2006

AbstractThe differences in surface charge of different bacteria can be exploited for their separation by capillary electrophoresis. However, this method of separation of microorganisms is beset with various drawbacks such as adhesion of bacteria to the fused silica surface or cluster formation. To overcome these phenomena we investigated the addition of poly(ethylene oxide) as a focusing agent to the running buffer and used calcium and myoinositol hexakisphosphate as specific ions that interact with the bacterial surface, changing its electrical properties and electrophoretic mobilities. In the present work, we applied CZE to identification of E. coli in infected urine (direct injection) from patients with urinary tract infections and to identification of Helicobacter pylori, which is a gram‐negative bacillus responsible for one of the most common infections found in humans worldwide. Helicobacter pylori colonize the stomach and are responsible for severe diseases of the gastric tract, ranging from chronic gastric ulcer to gastric cancer.
Influence of stationary phase properties on the separation of ionic liquid cations by RP‐HPLC
Authors: Buszewski Bogusław , Kowalska Sylwia , Stepnowski Piotr 
Published: May 2006

AbstractDifferent types of columns with specific structural properties were used for the separation of mixtures of ionic liquid cations. Two of them were home‐made packings and the other two were commercial stationary phases. One of the home‐made packings contained cholesterol ligands bonded chemically to silica (SG‐CHOL) whereas the other one was a mixed stationary phase (SG‐MIX) with cyanopropyl, aminopropyl, phenyl, octyl, and octadecyl ligands. RP‐18e Innovation ChromolithTM Performance and Macrosphere 300 C4 packings were also used. A comparison of the separation possibilities offered by these columns for the substances in question revealed significant differences in performance. Packings containing surface‐bonded functional groups that are able to undergo protonation are not suitable for separation of such compounds under the given analysis conditions (pH = 4). The best results were obtained for two alkyl stationary phases: butyl and octadecyl. Cluster analysis has also been performed for comparison of the ionic liquid cation properties.
Road construction impacts on stream suspended sediment loads in a nested catchment system in Nepal
Authors: Merz J. , Dangol P. M. , Dhakal M. P. , Dongol B. S. , Nakarmi G. , Weingartner R. 
Published: May 2006

AbstractIn terms of erosion and elevated suspended sediment concentrations, road construction has a major impact on the environment, which is described in this paper. In the Andheri Khola catchment, Nepal, the sediment regime of a stream at different locations within the catchment suddenly changed between 1999 and 2000. The only explanation for this change was the construction of the Bardibas‐Dhulikhel highway, which was initiated in this area in January 2000 and completed in March 2000. The changes in suspended sediment concentration could be shown both visually as well as statistically at three different locations in the catchment with a catchment without any impact of the road as a control. Other possible reasons for the change could be excluded by using the available data from the catchment. The impact of the road was estimated to range from 300 to 500 per cent in terms of change in sediment yield per annum. Copyright © 2006 John Wiley & Sons, Ltd.
An Er:YAG laser endoscopic fiber delivery system for lithotripsy of salivary stones
Authors: Raif Joshua , Vardi Michael , Nahlieli Oded , Gannot Israel 
Published: May 2006

AbstractBackground and ObjectivesEndoscopic applications of Erbium:YAG lasers are still very limited due to lack of appropriate fiber delivery capabilities. Recent reports on potential advantages of this laser for lithotripsy of ureteral stones prompted us to develop an Er:YAG fiber delivery system for endoscopic lithotripsy of salivary stones. We report on the development of this system and its clinical use on 17 patients.Study Design/Materials and MethodsHo:YAG and Er:YAG laser fragmentation performances were initially compared. Optimal laser parameters for lithotripsy of salivary stones were then established ex vivo using a commercial dental Er:YAG laser (Lumenis Opusdent 20). Metal hollow waveguides optimized for Er:YAG laser transmission were end sealed with a polished sapphire rod of 0.63 mm diameter and designed to adapt to the Opusdent laser and to a Storz sialoendoscope. The system was tested ex vivo for durability and clinical compatibility at input energies up to 700 mJ, 10–20 Hz. Following Helsinki approval the system was clinically tested on 17 patients with sialolithiasis.ResultsLithotripsy threshold was around 80 mJ/pulse (26 J/cm2) while efficient fragmentation, with microscopic fragments, was observed at an output energy range of 150–300 mJ/pulse. At 10 Hz, fragmentation rates of about 1.8 mm3/second were achieved enabling lithotripsy of a 6 mm stone in about 2 minutes. Front surface damage to the sapphire rod occurred but did not contribute to significant loss in fragmentation efficiency. Of the 21 stones treated clinically, 5 were fully fragmented, 7 were prepared for extraction by mini forceps, and 9 were released from surrounding soft tissues for subsequent removal. Fifteen of the 18 treated glands returned to normal function without any symptoms.ConclusionsThe Er:YAG endoscopic delivery system described is a clinically viable and cost‐effective device for a range of hard and soft tissue wet field applications accessible through rigid or semi‐rigid endoscopes. Further improvements in the waveguide may allow access also through fully flexible endoscopes. Lasers Surg. Med. 38:580–587, 2006. © 2006 Wiley‐Liss, Inc.
Analysis of pesticides in water by liquid chromatography‐tandem mass spectrometric techniques
Authors: Kuster Marina , de Alda Maria López , Barceló Damià 
Published: May 2006

AbstractPesticide residues continue to be the focus of many environmental studies, and the number of articles describing the development of more advanced, multiresidue analytical methodologies does not decline. The use of liquid chromatography‐mass spectrometry based on single quadrupole or ion trap analyzers is consolidated for this purpose. The implementation, in the near future, of more sophisticated mass analyzers, such as triple quadrupole and hybrid quadrupole‐time‐of‐flight is anticipated for routine analysis. This article reviews the various works published so far in the literature for the determination of pesticides and transformation products (TPs) in water by means of liquid chromatography (LC) coupled to tandem mass spectrometry. It discusses the various ionization sources and analyzers used for this purpose, as well as the extraction procedures employed for previous sample preconcentration. Because of the widespread use of triple quadrupole analyzers for the generation of pesticides levels in water using tandem mass spectrometry, a table compiling the transitions monitored for ca. 70 compounds is also included. © 2006 Wiley Periodicals, Inc.
Association between amantadine and the onset of dementia in Parkinson's disease
Authors: Inzelberg Rivka , Bonuccelli Ubaldo , Schechtman Edna , Miniowich Ala , Strugatsky Rosa , Ceravolo Roberto , Logi Chiara , Rossi Carlo , Klein Colin , Rabey J. Martin 
Published: May 2006

AbstractThe objective of this study is to compare the occurrence of dementia among Parkinson's disease (PD) patients treated with amantadine (AM group) with those never exposed to it (NoAM group). PD dementia shares neuroanatomical and biochemical similarities with Alzheimer's disease (AD). Memantine, an N‐methyl‐D‐aspartate (NMDA) receptor antagonist has been shown to be beneficial in AD. Memantine is a dimethyl derivative of amantadine, which also possesses NMDA receptor blocking properties. We hypothesized that amantadine could have a beneficial effect on the occurrence of PD dementia. PD patients attending the Movement Disorders Clinics in Hillel Yaffe, Asaf Harofe Medical Centers (Israel) and Pisa (Italy) were included. Taking the onset of dementia as the endpoint, survival curves for AM and NoAM patients were estimated by the Kaplan–Meier method. The study population consisted of 593 patients (age, 69.5 ± 9.9 years; PD duration, 9.2 ± 6.0 years; 263 patients (44%) amantadine treated). The endpoint of dementia was reached by 116 patients (20%). PD duration until dementia was significantly longer for AM patients (9.1 ± 5.7 years) than for NoAM patients (5.9 ± 4.6 years, P = 0.006). The duration of amantadine exposure positively correlated with PD duration until dementia (P = 0.0001). Survival analysis, taking dementia onset as endpoint, showed slower mental decline in AM patients (Log rank P = 0.0049, Wilcoxon P = 0.0024). Mini‐Mental State Examination scores were significantly higher for AM patients than for the NoAM group (P = 0.01). Age of PD onset also significantly influenced the duration of PD until dementia. Amantadine use may delay the onset of dementia in PD patients and may attenuate its severity. © 2006 Movement Disorder Society
Methylphenidate fails to improve gait and muscle tone in patients with sporadic and hereditary spastic paraplegia
Authors: Klebe Stephan , Deuschl Günther , Stolze Henning 
Published: May 2006

AbstractBased on its action on multiple neurotransmitters, including dopamine, methylphenidate (MPH) is of growing interest as a possible treatment option for several movement disorders. Of special interest are diseases that share gait disturbance and cognitive decline. Based on a single case observation in a patient with hereditary spastic spinal paraplegia (HSP) in which gait was improved with MPH, we performed an open‐label study with a longitudinal follow‐up in 22 patients with HSP and its sporadic form (SSP). The patients were treated for 6 months with 60 mg of MPH per day. Computerized gait analysis and different scores were performed at baseline, after 6 weeks, and after 6 months of treatment. Although at 6 weeks, the gait velocity was somewhat improved, the drug failed to show any effect on other gait parameters and had no beneficial effect at all after 6 months. Although MPH is of interest for several movement disorders, our study did not show a beneficial effect. © 2006 Movement Disorder Society
Structure and intramolecular flexibility of β‐cyclodextrin complex with (−)‐epigallocatechin gallate in aqueous solvent
Authors: Ishizu Takashi , Hirata Chikako , Yamamoto Hideji , Harano Kazunobu 
Published: May 2006

AbstractThe probable structure of the inclusion complex of β‐cyclodextrin (β‐CD) and (−)‐epigallocatechin gallate (EGCg) in D2O was investigated using several NMR techniques. EGCg formed a 1:1 complex with β‐CD, in which the A ring and a portion of the C ring of EGCg were included at the head of the phenolic hydroxyl group attached to C7 of EGCg in the β‐CD cavity from the wide secondary hydroxyl group side. In the 1:1 complex with β‐CD, EGCg maintained the conformation in which the B and B′ rings of EGCg took pseudoequatorial and pseudoaxial positions with respect to the C ring, respectively. The structure of the inclusion complexes of β‐CD and EGCg obtained from NMR experiments supported those determined from AM1 semiempirical SCF MO calculations well. Copyright © 2006 John Wiley & Sons, Ltd.
Capillary morphogenesis gene (CMG)‐1 is among the genes differentially expressed in mouse male germ line stem cells and embryonic stem cells
Authors: Fujino Ryu‐Suke , Ishikawa Yu‐Ichiro , Tanaka Kiyoko , Kanatsu‐Shinohara Mito , Tamura Kazuhiro , Kogo Hiroshi , Shinohara Takashi , Hara Takahiko 
Published: May 2006

AbstractWe recently established a technique to expand male germ line stem (GS) cells in long‐term culture without losing their spermatogenic capacity. To gain insight into the genetic program of these cells, we compared the mRNA expression profile of GS cells with that of embryonic stem (ES) cells using DNA microarrays. We found 79 genes that were upregulated in GS cells compared to ES cells, including synaptonemal complex protein‐1, deleted in azoospermia‐like, ubiquitin‐conjugating enzyme E2B, and ubiquitin carboxy‐terminal hydrolase L1, all of which are functionally important for spermatogenesis. In addition, we identified a cDNA encoding the mouse ortholog of capillary morphogenesis gene (CMG)‐1. CMG‐1 transcripts were predominantly produced in spermatogonia and spermatocytes in mouse testis. When CMG‐1 expression was attenuated in a mouse spermatocyte‐derived cell line, GC‐2spd(ts), by a target‐specific short interfering RNA, the morphology of the cells was changed and the expression of cyclin D2 was abrogated. A reporter assay using a genomic region upstream of the mouse cyclin D2 gene revealed that this downmodulation occurs at the transcriptional level. We detected FLAG‐tagged CMG‐1 protein in the nuclei of transfected COS7 cells, suggesting that CMG‐1 may play a unique role in the transcriptional regulation of the cyclin D2 gene. The upregulated GS genes identified in this study will provide useful information for the future investigation of spermatogonial stem cells and the early phase of male germ cell differentiation. Mol. Reprod. Dev. 955–966, 2006. © 2006 Wiley‐Liss, Inc.
Object‐oriented finite element analysis of thermo‐hydro‐mechanical (THM) problems in porous media
Authors: Wang Wenqing , Kolditz Olaf 
Published: May 2006

AbstractThe design, implementation and application of a concept for object‐oriented in finite element analysis of multi‐field problems is presented in this paper. The basic idea of this concept is that the underlying governing equations of porous media mechanics can be classified into different types of partial differential equations (PDEs). In principle, similar types of PDEs for diverse physical problems differ only in material coefficients. Local element matrices and vectors arising from the finite element discretization of the PDEs are categorized into several types, regardless of which physical problem they belong to (i.e. fluid flow, mass and heat transport or deformation processes). Element (ELE) objects are introduced to carry out the local assembly of the algebraic equations. The object‐orientation includes a strict encapsulation of geometrical (GEO), topological (MSH), process‐related (FEM) data and methods of element objects. Geometric entities of an element such as nodes, edges, faces and neighbours are abstracted into corresponding geometric element objects (ELE–GEO). The relationships among these geometric entities form the topology of element meshes (ELE–MSH). Finite element objects (ELE–FEM) are presented for the local element calculations, in which each classification type of the matrices and vectors is computed by a unique function. These element functions are able to deal with different element types (lines, triangles, quadrilaterals, tetrahedra, prisms, hexahedra) by automatically choosing the related element interpolation functions. For each process of a multi‐field problem, only a single instance of the finite element object is required. The element objects provide a flexible coding environment for multi‐field problems with different element types. Here, the C++ implementations of the objects are given and described in detail. The efficiency of the new element objects is demonstrated by several test cases dealing with thermo‐hydro‐mechanical (THM) coupled problems for geotechnical applications. Copyright © 2006 John Wiley & Sons, Ltd.
On the physics of block copolymers
Authors: Lecommandoux S , Borsali R 
Published: May 2006

AbstractThis article highlights some original block copolymer properties that have been studied in recent years at the Physico‐Chemistry group at the LCPO, giving our view on the physics of block copolymers in solutions (disordered state and self‐assembly) and in the bulk (nano‐organized films). In particular, we show that beyond the classical results on flexible–flexible block copolymer chains, the architecture (rigidity of the blocks, cyclization, etc) as well as external parameters (temperature, pH, ionic strength) play an important role in the different phases of a material made from block copolymers with controlled architectures. The properties of the various block copolymer systems investigated, in aqueous or organic media, are discussed in terms of free block copolymer chains, self‐assemblies and nano‐structured/nano‐organized films with the aid of techniques such as scattering (light, X‐rays, neutrons) and imaging (AFM, TEM). Copyright © 2006 Society of Chemical Industry
Origin of the methylene bonds in poly[2‐methoxy‐5‐(2′‐ethyl‐hexyloxy)‐1,4‐phenylenevinylene] prepared according to Gilch's method: novel applications
Authors: Lin King‐Fu , Fan Yang‐Liang , Chow Hsuan‐Liang 
Published: May 2006

AbstractImpurities containing methylene bridges between 2‐((2′‐ethylhexyl)oxy)‐5‐methoxy‐benzene molecules are inevitably formed during the synthesis of 1,4‐bis(chloromethyl)‐2‐((2′‐ethylhexyl)oxy)‐5‐methoxy‐benzene, the monomer used in the preparation of poly[2‐methoxy‐5‐(2′‐ethyl‐hexyloxy)‐1,4‐phenylenevinylene] (MEH‐PPV), but they can be removed by double recrystallization of the monomer prior to polymerization. When impurities containing methylene bridges participate in a Gilch polymerization, the methylene bonds formed in the main chains are prone to break at 200 °C, that is, at least 150 °C below the major degradation temperature of defect‐free MEH‐PPV. Interestingly, the thermal treatment used to break the methylene bonds present reduces the chain aggregation of MEH‐PPV during film formation and induces its blends with poly(2,3‐diphenyl‐5‐octyl‐p‐phenylene‐vinylene) (DPO‐PPV) to form a morphology similar to that of block copolymers. Both significantly enhance the luminescence properties. Copyright © 2006 Society of Chemical Industry
Small angle neutron scattering study of the structure and hydration of polyoxyethylene‐block‐polyoxybutylene in aqueous solution
Authors: Fairclough J Patrick A , Norman Alexander Iain , Shaw Benjamin , Nace V Mark , Heenan Richard K 
Published: May 2006

AbstractThe micellar structure of a polyoxyethylene‐block‐polyoxybutylene diblock copolymer (E18B10; E = (OCH2CH2); B = OCH2CH(CH2CH3)) in water was studied by small angle neutron scattering. Results show a polydisperse spherical micelles at temperatures below 45 °C, a possible mixed phase at 45 °C and flexible worm‐like micelles at 65 °C. The spherical micelles at 25 and 35 °C have radii of 39 and 40 Å and degrees of hydration of 28% and 26%, respectively. The worm‐like micelles have a total length of approximately 1850 Å, with segment lengths of 123 Å, a core radius, Rax = 30 Å and hydration of 23%, at 65 °C. Copyright © 2006 Society of Chemical Industry
Bi‐axial self‐reinforcement of high‐density polyethylene induced by high‐molecular weight polyethylene through dynamic packing injection molding
Authors: Lei Jun , Zhang Zhenjun , Jiang Chaodong , Shen Kaizhi 
Published: May 2006

AbstractPreviously, bi‐axial self‐reinforcement of high‐density polyethylene (HDPE) was achieved through a uni‐axial shear stress field introduced by dynamic packing injection molding technology. Here, further improvement of tensile strength along the flow direction (MD) was achieved by blending a small amount of high‐molecular‐weight polyethylene (HMWPE) with HDPE, while the tensile strength along the transverse direction (TD) still substantially exceeded that of conventional moldings. Tensile strengths in both flow and transverse directions were considerably enhanced, with improvements from 23 MPa to 76 MPa in MD and from 23 MPa to 31 MPa in TD. The effect of HMWPE content and molding parameters on tensile properties was also investigated. The tensile strength along MD was highly dependent on HMWPE content, oscillating cycle, mold temperature, melt temperature and packing pressure, while that along TD was insensitive to composition and processing parameters within the selected design space. According to the stress–strain curves, samples with HMWPE produced by dynamic packing injection molding had a special tensile failure mode in MD, different from both typical plastic and brittle failure modes. There were no yielding and necking phenomena, which are characteristic during tensile testing of plastic materials, but there was still a considerably higher elongation compared to those of brittle materials. However, in TD, all dynamic injection molding samples exhibited plastic failure as did typical conventional injection molding samples. Copyright © 2006 Society of Chemical Industry
Preparation and characterization of polydiphenylamine/multi‐walled carbon nanotube composites
Authors: Lu Xiaofeng , Chao Danming , Zheng Jiani , Chen Jingyu , Zhang Wanjin , Wei Yen 
Published: May 2006

AbstractWe describe the synthesis of methane sulfonic acid (MeSA)‐doped poly(diphenylamine) (PDPA) with carboxylic groups containing multi‐walled carbon nanotubes (c‐MWNTs) via in situ polymerization. Diphenylamine monomers were adsorbed on to the surface of c‐MWNTs and polymerized to form PDPA/c‐MWNT composites. SEM and TEM images indicated two different types of materials: the thinner fibrous phase and the larger globular phase. The individual fibrous phase had a diameter around 100–130 nm, which should be the carbon nanotubes (diameter 20–30 nm) coated with a PDPA layer. The structure of PDPA/c‐MWNT composites was characterized by FTIR, UV‐visible spectroscopy and X‐ray diffraction patterns. The electrical conductivities of PDPA/c‐MWNT composites were much higher than that of PDPA without c‐MWNTs. Copyright © 2006 Society of Chemical Industry