bluuebunny/crossref_metadata_2025_split huggingface dataset:
ATP‐binding to P‐type ATPases as revealed by biochemical, spectroscopic, and crystallographic experiments
Authors: Kubala Martin 
Published: April 2006

AbstractP‐type ATPases form a large family of cation translocating ATPases. Recent progress in crystallography yielded several high‐resolution structures of Ca2+‐ATPase from sarco(endo)plasmic reticulum (SERCA) in various conformations. They could elucidate the conformational changes of the enzyme, which are necessary for the translocation of cations, or the mechanism that explains how the nucleotide binding is coupled to the cation transport. However, crystals of proteins are usually obtained only under conditions that significantly differ from the physiological ones and with ligands that are incompatible with the enzyme function, and both of these factors can inevitably influence the enzyme structure. Biochemical (such as mutagenesis, cleavage, and labeling) or spectroscopic experiments can yield only limited structural information, but this information could be considered relevant, because measurement can be performed under physiological conditions and with true ligands. However, interpretation of some biochemical or spectroscopic data could be difficult without precise knowledge of the structure. Thus, only a combination of both these approaches can extract the relevant information and identify artifacts. Briefly, there is good agreement between crystallographic and other experimental data concerning the overall shape of the molecule and the movement of cytoplasmic domains. On the contrary, the E1‐AMPPCP crystallographic structure is, in details, in severe conflict with numerous spectroscopic experiments and probably does not represent the physiological state. Notably, the E1‐ADP‐AlF4 structure is almost identical to the E1‐AMPPCP, again suggesting that the structure is primarily determined by the crystal‐growth conditions. The physiological relevance of the E2 and E2‐P structures is also questionable, because the crystals were prepared in the presence of thapsigargin, which is known to be a very efficient inhibitor of SERCA. Thus, probably only crystals of E1‐2Ca conformation could reflect some physiological state. Combination of biochemical, spectroscopic, and crystallographic data revealed amino acids that are responsible for the interaction with the nucleotide. High sequence homology of the P‐type ATPases in the cytoplasmic domains enables prediction of the ATP‐interacting amino acids also for other P‐type ATPases. Proteins 2006. © 2006 Wiley‐Liss, Inc.
Susceptibility of adult Coccinella septempunctata (Coleoptera: Coccinellidae) to insecticides with different modes of action
Authors: Bozsik András 
Published: April 2006

AbstractFive insecticides (pyriproxifen, imidacloprid, deltamethrin + heptenophos, lambda‐cyhalothrin and Bacillus thuringiensis Berliner subsp. tenebrionis) were examined in the laboratory for their acute detrimental side‐effects at field rates on adult seven‐spot ladybird beetle, Coccinella septempunctata L. The toxicity of the preparations was determined by measuring the acute surface contact effects (dried spray on leaves of Philadelphus coronarius L.), except for B. thuringiensis where mixed pollen was treated. Four to six concentrations were tested (pyriproxifen 12.5, 25, 50, 100, 200, 400 mg AI litre−1; imidacloprid 62.4, 125, 250, 500 mg AI litre−1; deltamethrin + heptenophos 26.4, 53.1, 106.3, 212.5 mg AI litre−1; lambda‐cyhalothrin 1.1, 3.4, 10, 30 mg AI litre−1; B. thuringiensis 1.5, 3.0, 12.0, 48, 192, 768 mg AI litre−1), with 22 adults exposed per concentration. All tests were conducted in the laboratory of the Plant Protection Department (University of Debrecen, Hungary) at 22–25 °C, 40–60% RH, under a 16:8 h light:dark photoperiod in 1998–1999. Data were analyzed by probit analysis, probit transformation and analysis of variance. According to different categories of evaluation, pyriproxifen, imidacloprid and B. thuringiensis subsp. tenebrionis seem to be safe for C. septempunctata adults but the other two preparations were moderately harmful to them, which requires further semi‐field or field tests to measure their real effect under field conditions. Copyright © 2006 Society of Chemical Industry
XPS characterization of nitrogen‐doped carbon nanotubes
Authors: Morant C. , Andrey J. , Prieto P. , Mendiola D. , Sanz J. M. , Elizalde E. 
Published: April 2006

AbstractIn this work, CNTs have been bombarded with low energy N ions. X‐ray photoelectron spectroscopy have been used to determine the binding configuration of the N‐doped CNTs. AFM was also used to determine their morphology and mechanical properties. The same morphology is maintained after the N2+ bombardment. XPS analysis shows that the N 1s core level spectra for N‐doped CNTs can be deconvoluted in terms of two peaks related to sp2 (C–N=C) and sp3 hybridization (C–N configuration). This interpretation is in concordance with the increase of the hardness observed by AFM nanoindentations when the sp3 contributions increase. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
3rd order nonlinear optical properties of Au:SiO2 nanocomposite films with varying Au particle size
Authors: Jun H.‐S. , Lee K.‐S. , Yoon S.‐H. , Lee T. S. , Kim I. H. , Jeong J.‐H. , Cheong B. , Kim D. S. , Cho K. M. , Kim W. M. 
Published: April 2006

AbstractFour Au:SiO2 composite films with varying Au particle size at fixed volume fraction were fabricated by alternate sputtering, and their 3rd order nonlinear optical properties were investigated by the z ‐scan technique using picosecond pulse laser. TEM analysis was used to estimate the particle size for samples with varying Au nominal thickness, and size dependent linear absorption spectra were examined. Particle size dependence on the imaginary part of 3rd order susceptibility at surface plasmon wavelength together with the dispersion of the real and the imaginary components around surface plasmon wavelength were resolved and compared with the theoretical values. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Towards the application of nanocrystalline metals in MEMS
Authors: Baghbanan Mohammadreza , Erb Uwe , Palumbo Gino 
Published: April 2006

AbstractA comparison is presented of the cross‐sectional mechanical properties (i.e. hardness and Young's modulus) for electrodeposited microsystem components with conventional polycrystalline and nanocrystalline structures. It is shown that nanocrystalline electrodeposits exhibit considerabily improved cross‐sectional properties both in terms of uniformity (hardness and Young's modulus) and overall hardness level. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Carbon nanotubes and nucleic acids: tools and targets
Authors: Onoa Bibiana , Zheng Ming , Dresselhaus Mildred S. , Diner Bruce A. 
Published: April 2006

AbstractNucleic acids, with their intrinsic structural properties as well as their high specificity, are playing an important role in the rapid development of nano‐technologies. In turn, these new technologies and their efficient performance enable fast and precise methods for detection of nucleic acids, improving the diagnosis of diseases and identification of pathogens. We discuss the use of nucleic acids to disperse and sort single walled carbon nanotubes (SWNTs), and carbon nanotube‐based field effect transistors (CNT‐FETs) to electrically detect specific nucleic acid sequences. Both DNA and RNA are efficient agents for dispersion and separation of SWNTs by diameter and chirality. Fractions enriched in a narrow band gap distribution of DNA:SWNT hybrids do not alter the electronic performance of field effect transistors. A CNT‐FET fulfills the requirements for a nanosensing device that can greatly exceed the existing technologies. Electrical detection of specific nucleic acid sequence could potentially overcome the current limitations of optical detection, by increasing sensitivity and speed, while reducing sample manipulation, size, and cost. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Coupling carbon nanotubes through DNA linker using a biological recognition complex
Authors: Goux‐Capes L. , Filoramo A. , Cote D. , Bourgoin J.‐Ph. , Patillon J.‐N. 
Published: April 2006

AbstractWe present a simple and versatile method for linking single wall carbon nanotubes (SWNT) together through DNA by non‐covalent chemistry using streptavidin‐biotin recognition complex. Streptavidin coated SWNTs are reacted with biotin or bis‐biotin ended DNA double strands leading to SWNT‐DNA and SWNT‐DNA‐SWNT adducts in high yield. This method avoids strong acidic treatment of SWNTs prior to functionalization as usually required in covalent routes. Complementary characterizations by gel electrophoresis and AFM demonstrated the efficiency of the present binding method. In addition, SWNTs bound to DNA can be aligned on a substrate using the combing properties of DNA strands, bringing a new tool into the toolkit for self‐assembling SWNTs onto surfaces. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Analysis of the cross-reactivity and of the 1.5 Å crystal structure of the Malassezia sympodialis Mala s 6 allergen, a member of the cyclophilin pan-allergen family
Authors: Glaser Andreas G. , Limacher Andreas , Flückiger Sabine , Scheynius Annika , Scapozza Leonardo , Crameri Reto 
Published: April 2006

Cyclophilins constitute a family of proteins involved in many essential cellular functions. They have also been identified as a panallergen family able to elicit IgE-mediated hypersensitivity reactions. Moreover, it has been shown that human cyclophilins are recognized by serum IgE from patients sensitized to environmental cyclophilins. IgE-mediated autoreactivity to self-antigens that have similarity to environmental allergens is often observed in atopic disorders. Therefore comparison of the crystal structure of human proteins with similarity to allergens should allow the identification of structural similarities to rationally explain autoreactivity. A new cyclophilin from Aspergillus fumigatus (Asp f 27) has been cloned, expressed and showed to exhibit cross-reactivity in vitro and in vivo. The three-dimensional structure of cyclophilin from the yeast Malassezia sympodialis (Mala s 6) has been determined at 1.5 Å (1 Å=0.1 nm) by X-ray diffraction. Crystals belong to space group P41212 with unit cell dimensions of a=b=71.99 Å and c=106.18 Å. The structure was solved by molecular replacement using the structure of human cyclophilin A as the search model. The refined structure includes all 162 amino acids of Mala s 6, an active-site-bound Ala-Pro dipeptide and 173 water molecules, with a crystallographic R- and free R-factor of 14.3% and 14.9% respectively. The overall structure consists of an eight-stranded antiparallel β-barrel and two α-helices covering the top and bottom of the barrel, typical for cyclophilins. We identified conserved solvent-exposed residues in the fungal and human structures that are potentially involved in the IgE-mediated cross-reactivity.
Three‐Dimensional Reconstruction and Modeling of Middle Ear Biomechanics by High‐Resolution Computed Tomography and Finite Element Analysis
Authors: Lee Chia‐Fone , Chen Peir‐Rong , Lee Wen‐Jeng , Chen Jyh‐Horng , Liu Tien‐Chen 
Published: April 2006

AbstractObjective: To present a systematic and practical approach that uses high‐resolution computed tomography to derive models of the middle ear for finite element analysis.Study Design: This prospective study included 31 subjects with normal hearing and no previous otologic disorders. Temporal bone images obtained from 15 right ears and 16 left ears were used for evaluation and reconstruction.Methods: High‐resolution computed tomography of temporal bone was performed using simultaneous acquisition of 16 sections with a collimated slice thickness of 0.625 mm. All images were transferred to an Amira visualization system for three‐dimensional reconstruction. The created three‐dimensional model was translated into two commercial modeling packages, Patran and ANSYS, for finite element analysis.Result: The characteristic dimensions of the model were measured and compared with previously published histologic section data. This result confirms that the geometric model created by the proposed method is accurate except that the tympanic membrane is thicker than when measured by the histologic section method. No obvious difference in the geometrical dimension between right and left ossicles was found (P > .05). The three‐dimensional model created by finite element method and predicted umbo and stapes displacements are close to the bounds of the experimental curves of Nishihara's, Huber's, Gan's, and Sun's data across the frequency range of 100 to 8000 Hz.Conclusion: The model includes a description of the geometry of the middle ear components and dynamic equations of vibration. The proposed method is quick, practical, low‐cost, and, most importantly, noninvasive as compared with histologic section methods.
Vestibular Evoked Myogenic Potential (VEMP) in Patients With Ménière's Disease With Drop Attacks
Authors: Timmer Ferdinand C. A. , Zhou Guangwei , Guinan John J. , Kujawa Sharon G. , Herrmann Barbara S. , Rauch Steven D. 
Published: April 2006

AbstractObjective: In this retrospective study, we tested the hypothesis that vestibular evoked myogenic potential (VEMP) thresholds are more often elevated or absent in patients with Ménière's disease experiencing Tumarkin drop attacks than in other patients with Ménière's disease.Methods: Subjects included normal subjects (n = 14) and patients with unilateral Ménière's disease by AAO‐HNS (1995) diagnostic criteria with (n = 12) and without (n = 82) Tumarkin drop attacks at a large specialty hospital otology service. VEMP threshold testing was conducted using 250, 500, and 1,000 Hz tone burst stimuli.Results: VEMP responses were present in at all frequencies in both ears of all normal subjects. In unaffected ears of patients with unilateral Ménière's disease, VEMPs were undetectable in 13% of measurements attempted. This number rose to 18% in affected ears of patients with unilateral Ménière's disease and to 41% in Meniere ears with Tumarkin drop attacks. Frequency tuning of the VEMP response in normal subjects showed lowest thresholds at 500 Hz. In Meniere ears, the tuning was altered such that the 500‐Hz thresholds were higher than the 1,000‐Hz thresholds. There was a gradient of threshold elevation and altered tuning that corresponded to the gradient of worsening disease.Conclusion: Our findings support the hypothesis that Tumarkin drop attacks arise from advanced disease involving the saccule and that VEMP may be a clinically valuable metric of disease severity or progression in patients with Ménière's disease.
Audiologic Performance and Benefit of Cochlear Implantation in Usher Syndrome Type I
Authors: Pennings Ronald J. E. , Damen Godelieve W. J. A. , Snik Ad F. M. , Hoefsloot Lies , Cremers Cor W. R. J. , Mylanus Emmanuel A. M. 
Published: April 2006

AbstractObjective: The objective of this retrospective study was to evaluate the benefit and performance of cochlear implantation in patients with Usher syndrome type 1 (USH1).Methods: Fourteen patients with a clinical diagnosis of USH1 were included. Mutation analysis of USH1 genes was performed in all of them. All patients filled in the G(C)BI questionnaire, which measures the benefit of implantation. In addition, equivalent hearing level scores (EHL) were calculated to measure performance. Correlations between the mentioned parameters were studied.Results: One or two pathogenic mutations were identified in seven of the 14 examined patients. Similar to previous studies, it was demonstrated that implantation at an earlier age results in better performance than implantation at higher age. Cochlear implantation performed within the first 2 decades of life was beneficial to 13 of 14 (93%) of the patients with USH1. Finally, the EHL score and the G(C)BI score showed a significant correlation; the benefit of implantation increases with a decreasing EHL score.Conclusions: Cochlear implantation in patients with USH1 improves the audiologic performance when patients are implanted at an earlier age and is beneficial according to the G(C)BI when performed within the first 2 decades of life.
A Short Course of Oral Prednisone Followed by Intranasal Budesonide Is an Effective Treatment of Severe Nasal Polyps
Authors: Benítez Pedro , Alobid Isam , de Haro Josep , Berenguer Joan , Bernal‐Sprekelsen Manuel , Pujols Laura , Picado Cesar , Mullol Joaquim 
Published: April 2006

AbstractBackground: Nasal polyposis is an inflammatory disease of unknown etiology. This study aimed to evaluate the effect of a short course of oral prednisone followed by intranasal budesonide on nasal symptoms, polyp size, nasal flow, and computed tomography scan.Methods: Eighty‐four patients with severe nasal polyps were included. After a steroid washout period, patients were randomized into two groups: group A (n = 63) received oral prednisone for 2 weeks and group B (n = 21) did not receive any steroid treatment. Patients from group A received intranasal budesonide for 12 weeks.Results: Atopy was positive in 36.8% of patients. Blood eosinophilia was higher in asthmatic (7.2 ± 0.7%, P < .05) than in nonasthmatic (3.0 ± 0.4%) patients. Asthmatic patients showed higher scores on nasal obstruction and loss of smell than nonasthmatics. Oral steroids caused a significant improvement in all nasal symptoms and improved polyp size (2.1 ± 0.1, P < .05) and nasal flow (560 ± 35 cm3/s, P < .05) compared with nontreated patients (2.8 ± 0.1 and 270 ± 34 cm3/s, respectively). Intranasal budesonide maintained the improvement on nasal symptoms, polyp size, and nasal flow. Steroid treatment reduced the computed tomography scan score (15.4 ± 1, P < .05) compared with before treatment (18.2 ± 0.8).Conclusion: A short course of oral steroids improved all nasal symptoms, polyp size, and nasal flow, whereas intranasal steroid maintain this effect.
Soft‐Tissue Sarcomas of the Head and Neck: A Retrospective Analysis of the Alberta Experience 1974 to 1999
Authors: Huber Gerhard Frank , Matthews T Wayne , Dort Joseph C. 
Published: April 2006

AbstractBackground: Soft‐tissue sarcomas (STS) of the head and neck constitute a heterogeneous group of rare malignant tumors occurring in an uncommon site. The most common subtypes of STS in the head and neck are malignant fibrous histiocytoma, dermatofibrosarcoma protuberans, and fibrosarcoma. Evidence based subtype‐specific treatment decisions are often not possible.Methods: The medical records of 110 patients diagnosed with head and neck sarcomas were reviewed. All were treated at one of the two major Cancer Centers in Alberta, Canada, between 1974 and 1999. Potential prognostic factors including age, sex, tumor size, histology, grade, tumor location (superficial or deep), and use of adjuvant treatment were evaluated. Cox proportional hazards models were developed to study the impact of these covariates on survival.Results: The median duration of follow‐up was 61.5 months. Five year overall, disease specific, and relapse free survival were 65.8%, 83.4%, and 74.2%, respectively. With use of a Cox proportional‐hazards model, tumor stage and grade were important prognostic factors affecting survival.Conclusions: Tumor size and grade were important prognostic factors affecting survival. Tumor location in relation to the superficial fascia (depth) was the best predictor of outcome. The overall and disease‐free survival in this patient group was excellent. However, this likely caused by the high proportion of patients with low‐grade tumors in our study.
Merkel Cell Carcinoma: Does Tumor Size or Depth of Invasion Correlate With Recurrence, Metastasis, or Patient Survival?
Authors: Sandel Henry D. , Day Terry , Richardson Mary S. , Scarlett Matthew , Gutman Katharine A. 
Published: April 2006

AbstractObjective: The objective of this retrospective study and literature review was to compare the clinical and histologic criteria including tumor size and depth of invasion with outcomes in patients with Merkel cell carcinoma.Methods: The state cancer registry provided patients (n = 46) diagnosed with Merkel cell carcinoma from 1992 through 2002. Pathology slides were reviewed by the author for tumor size, depth of invasion, Clark level, and margin status. Further clinical information and survival data were gathered from patient records. Statistical analysis was performed using t tests and Kaplan‐Meier survival curves. Patients were excluded from specific analysis based on misdiagnosis, unavailability of pathology slides, absent medical records, or those lost to follow up.Results: Disease‐free survival rates were 52%, 39%, and 9% at 1, 2, and 5 years, respectively. The average disease‐free interval was 18.4 months (range, 1–80 months). No correlation was found between tumor size (P = .49), depth (P = .41), or Clark level (P = .82) to overall survival. A trend was found comparing tumor size or depth of invasion with local recurrence (P = .07) but with no correlation to regional recurrence (P = .93 and P = .60) or distant metastasis (P = .16 and P = .24). Overall recurrence was found in 60.7% of patients with local recurrence occurring in 18.1%, regional recurrence 40.9%, and distant recurrence 47.8%. Comparing patients with positive versus negative margins at initial excision, local recurrence was found in 33.3% versus 9.09% (P = .19), regional recurrence 66.6% versus 27.2% (P = .08), and distant metastasis 66.6% versus 45.4% (P = .36), respectively.Conclusions: No correlation was found between tumor size or depth of invasion to patient survival or metastasis. However, there was a trend toward increased local and regional recurrence rates when comparing size and depth and in specimens with positive tumor margins. These outcomes are consistent with those reported in recent literature and further characterize the unpredictable nature of this disease. An aggressive approach should be taken, including wide local excision with negative tumor margins and lymph node dissection; however, larger multistate reviews are needed for additional support.
Utility of Positron Emission Tomography‐Computed Tomography in Identification of Residual Nodal Disease after Chemoradiation for Advanced Head and Neck Cancer
Authors: Gourin Christine G. , Williams Haydn T. , Seabolt Wesley N. , Herdman Anne V. , Howington Jed W. , Terris David J. 
Published: April 2006

AbstractObjectives: Planned neck dissection after chemoradiation (CR) is often advocated in patients with head and neck squamous cell cancer (HNSCC) with advanced nodal disease who demonstrate a clinical complete response to CR because identification of residual occult nodal disease is difficult. We sought to investigate the utility of positron emission tomography‐computed tomography (PET‐CT) in identifying patients with occult nodal disease after CR.Study Design: Nonrandomized retrospective cohort analysis.Materials and Methods: The medical records of all patients treated with primary CR for advanced HNSCC with N2 or N3 disease from December 2003 to June 2005 were reviewed. Patients with a clinical complete response were eligible for inclusion if PET‐CT performed at 8 to 10 weeks after CR showed no evidence of distant disease and they were treated with a planned neck dissection.Results: Seventeen patients met study criteria. PET‐CT was positive for residual nodal disease in 11 (64.7%) patients, with a standardized uptake value (SUV) range of 1.7 to 3.8. Pathologic examination revealed residual viable carcinoma in five (29.4%) patients, with tumor size ranging from 2.0 to 9.5 mm. Carcinoma was present in 2 of 11 (18.2%) patients with positive PET‐CT scans and 3 of 6 (50%) patients with negative PET‐CT scans. The sensitivity and specificity of PET‐CT in predicting occult nodal disease was 40% and 25%, respectively. There was no correlation between PET‐CT findings and histologic findings (P = .26) or between SUV and size of viable tumor (P = .67).Conclusions: A significant proportion of HNSCC patients with advanced neck disease harbor residual occult metastases after CR. PET‐CT is not sufficiently specific or sensitive to reliably predict the need for posttreatment neck dissection.