bluuebunny/crossref_metadata_2025 huggingface dataset:
Endoscopic ligation of the patulous eustachian tube as treatment for autophony
Authors: Rotenberg Brian W. , Busato Gian‐Marco , Agrawal Sumit K.
Published: October 2012

Objectives/Hypothesis:

Patulous eustachian tube remains a challenging management problem in otolaryngology. The autophony experienced by this patient population can be severe, and as yet no reliable surgical method exists to reduce or eliminate this annoying symptom. Our objective was to develop a novel endoscopic technique to assist these patients.

Study Design:

Longitudinal case series.

Methods:

A prospective longitudinal study was conducted of a series of consecutive patients undergoing surgery for patulous eustachian tube. Under transnasal endoscopic guidance, using a combination of fat plugging, endoluminal cauterization, and suture ligation, 14 ears underwent surgical treatment during a 4‐year period. The main outcome measure assessed was the level of autophony present after surgery as compared to baseline. Audiometric outcomes, surgical time, and complications were also recorded.

Results:

There was sustained satisfactory subjective improvement in the autophony in 12 of the 14 ears (85.7%) at primary surgery, with nine of these 12 ears (75%) demonstrating full autophony cessation. Wilcoxon signed rank test showed a significant improvement in autophony in the study population compared to baseline (z = 3.16, P < .001). The mean operating length of time per ear over the full duration of our series was approximately 45 minutes. Postoperative audiometry showed that surgery had no impact on hearing.

Conclusions:

Multilayer endoscopic ligation of the patulous eustachian tube resulted in a high autophony improvement rate. The procedure is technically straightforward, and results were sustained at 6‐month follow‐up. Laryngoscope, 2013
Treatment modalities and outcomes of olfactory neuroblastoma
Authors: Song Chang Myeon , Won Tae‐Bin , Lee Chul Hee , Kim Dong‐Young , Rhee Chae‐Seo
Published: October 2012

Objectives/Hypothesis:

To analyze the clinical features of olfactory neuroblastoma (ONB) and compare the treatment results according to various treatment modalities, and to validate various staging systems.

Study Design:

Retrospective analysis.

Methods:

This study included 35 patients with ONB. Treatment consisted of neoadjuvant chemotherapy and radiation therapy (seven patients), traditional craniofacial resection (TCFR, 12 patients), endoscopic craniofacial resection with craniotomy (ECFR, 11 patients), and transnasal endoscopic resection without craniotomy (five patients). The overall mean follow‐up period was 64.9 months and mean disease‐free survival (DFS) was 50.2 months.

Results:

Five‐year overall survival and 5‐year DFS rates were 76.0% and 61.8%, respectively. Five‐year DFS rates for nonsurgical treatment, TCFR, ECFR, and transnasal endoscopic resection without craniotomy group were 35.7%, 41.7%, 80.8%, and 100%, respectively (P = .01). Neck metastasis negatively affected survival (P = .03). DFS rate of patients in the endoscopic surgery group was higher than the nonendoscopic surgery group on Cox multivariate regression analysis (P = .02). The modified Kadish classification system predicted DFS more accurately than the Biller and Dulguerov classification system (P = .04). Locoregional recurrence occurred in 23% (period of recurrence after treatment, mean 49 months; range, 3–143) of patients with ONB, and distant metastasis in 26%. ECRF group showed lesser perioperative bleeding amount and shorter operation time compared with TCFR. However, the admission period was not statistically different.

Conclusions:

Endoscopic surgery for advanced ONB showed successful survival results compared with nonendoscopic surgery on multivariate analysis, and limited morbidities. Modified Kadish classification best predicted DFS for ONB. Long‐term follow‐up is necessary due to its late recurrence. Laryngoscope, 2012
Surgical resection of endolymphatic sac tumors in von Hippel‐Lindau disease: Findings, results, and indications
Authors: Kim H. Jeffrey , Hagan Marygrace , Butman John A. , Baggenstos Martin , Brewer Carmen , Zalewski Christopher , Linehan W. Marston , Lonser Russell R.
Published: October 2012

Objectives/Hypothesis:

To define the surgical treatment and outcomes of von Hippel‐Lindau (VHL) disease‐associated endolymphatic sac tumors (ELSTs), we analyzed consecutive VHL patients who underwent ELST resection.

Study Design:

Retrospective investigation of consecutive VHL patients who underwent resection of ELSTs at a clinical research center between 1999 and 2010.

Methods:

Analysis of serial clinical examinations, audiograms, imaging studies, and operative findings were analyzed.

Results:

Thirty‐one consecutive patients with ELSTs (15 males, 16 females) underwent resection of 33 tumors (mean follow‐up, 49.9 ± 48.0 months; range, 1.0–116 months). One patient had bilateral ELST resections and one patient underwent reoperation for recurrence. Mean age at surgery was 38.2 ± 10.2 years (range, 12–67 years). Whereas 29 ears (88%) had direct radiographic evidence of an ELST, four ears (12%) did not. Mean tumor size was 1.3 ± 1.1 cm (range, 0.2–5.2 cm). Whereas two patients (two ears, 6%) were asymptomatic, 29 patients (31 ears, 94% of ears) had associated audiovestibular symptoms, including sensorineural hearing loss (28 ears, 84%), tinnitus (24 ears,73%), and vertigo (21 patients, 68%). Postoperatively, hearing was stabilized (27) or improved (three) in 97% of 31 ears. Complete tumor resection was achieved in 30 ears (91% of 33 ears). Complications included cerebrospinal fluid leak in two ears (6%) and transient lower cranial nerve palsy in one ear (3%).

Conclusions:

Surgical resection of ELSTs can be performed with hearing preservation and a reduction in audiovestibular dysfunction. Early surgical resection can prevent or decrease disabling audiovestibular symptoms, enhance the opportunity for complete resection, and preserve hearing. Laryngoscope, 2012
The role of upper and lower airway patency in chronic rhinosinusitis with nasal polyps and asthma
Authors: Huang Zhenxiao , Zhou Bing , Zhang Qi , Huang Qian , Sun Yan , Wang Mingjie , Wang Xiangdong , Wang Chengshuo , Li Yunchuan , Cui Shunjiu
Published: October 2012

Objectives/Hypothesis:

To investigate the role of airway patency and factors associated with airway patency in patients with chronic rhinosinusitis with nasal polyps (CRSwNP) and asthma.

Study Design:

Retrospective study.

Methods:

The upper and lower airway patency of 140 patients with CRSwNP and asthma (asthma group) and 42 patients with CRSwNP without asthma (nonasthma control group) was measured using acoustic rhinometry, rhinomanometry, and spirometry. Total serum immunoglobulin E and eosinophil counts were also compared. The severity of nasal diseases in these patients was assessed via the Lund–Mackay score (LMS) and Lund–Kennedy score (LKS).

Results:

There was no difference between the asthma and nonasthma groups in terms of total nasal resistance at 75 Pa (R75T), bilateral minimum cross‐sectional area (MCAR+L), or bilateral nasal cavity volume between 0 and 7.0 cm3 (V7R+L). Forced expiratory volume in 1 second (FEV1) and forced expiratory flow between 25% and 75% of forced vital capacity (FEF25–75) of the asthma group were significantly lower than those of the nonasthma group. FEV1 and FEF25–75 were not correlated with R75T, MCAR+L, V7R+L, or severity of nasal disease. For the patients with asthma, LMS and serum eosinophil counts were independent predictors of MCAR+L.

Conclusions:

The presence of asthma may not influence upper airway patency in CRSwNP patients. In CRSwNP patients with asthma, impairment of upper airway patency was associated with changes in LMS and eosinophilia, and in these patients lower airway patency was significantly lower than that of the control group (without asthma). In CRSwNP patients with asthma, there was little or no association between upper and lower airway patency. Laryngoscope, 2013
Artificial neural network classification of pharyngeal high‐resolution manometry with impedance data
Authors: Hoffman Matthew R. , Mielens Jason D. , Omari Taher I. , Rommel Nathalie , Jiang Jack J. , McCulloch Timothy M.
Published: October 2012

Objectives/Hypothesis:

To use classification algorithms to classify swallows as safe, penetration, or aspiration based on measurements obtained from pharyngeal high‐resolution manometry (HRM) with impedance.

Study Design:

Case series evaluating new method of data analysis.

Methods:

Multilayer perceptron, an artificial neural network (ANN), was evaluated for its ability to classify swallows as safe, penetration, or aspiration. Data were collected from 25 disordered subjects swallowing 5‐ or 10‐mL boluses. Following extraction of relevant parameters, a subset of the data was used to train the models, and the remaining swallows were then independently classified by the ANN.

Results:

A classification accuracy of 89.4 ± 2.4% was achieved when including all parameters. Including only manometry‐related parameters yielded a classification accuracy of 85.0 ± 6.0%, whereas including only impedance‐related parameters yielded a classification accuracy of 76.0 ± 4.9%. Receiver operating characteristic analysis yielded areas under the curve of 0.8912 for safe, 0.8187 for aspiration, and 0.8014 for penetration.

Conclusions:

Classification models show high accuracy in classifying swallows from dysphagic patients as safe or unsafe. HRM‐impedance with ANN represents one method that could be used clinically to screen for patients at risk for penetration or aspiration. Laryngoscope, 2013
Resource utilization in primary repair of cleft palate
Authors: Owusu James A. , Liu Meixia , Sidman James D. , Scott Andrew R.
Published: October 2012

Objectives/Hypothesis:

To estimate the current incidence of cleft palate in the United States and to determine national variations in resource utilization for primary repair of cleft palate.

Study Design:

Retrospective analysis of a national, pediatric database (2009 Kids Inpatient Database).

Methods:

Patients aged 3 and below admitted for cleft palate repair were selected, using ICD‐9 codes for cleft palate and procedure code for primary (initial) repair of cleft palate. A number of demographic variables were analyzed, and hospital charges were considered as a measure of resource utilization.

Results:

Primary repair of cleft palate was performed on 1,943 patients. The estimated incidence was 0.11% with male to female ratio of 1.2:1. Regional incidence ranged from 0.09% (Northeast) to 0.12% (Midwest). The mean age at surgery was 13.4 months. The average length of stay was 1.9 days. The average total charge nationwide was $22,982, ranging from $17,972 (South) to $25,671 (Northeast). Average charge in a teaching institution was $4,925 higher than for nonteaching institutions. The strongest predictor of charge was length of stay, increasing charge by $7,663 for every additional hospital day (P < 0.01).

Conclusions:

National variations exist in resource utilization for primary repair of cleft palate, with higher charges in Northeastern states and teaching hospitals. The strongest predictor of increased resource use was length of stay, which was significantly higher at teaching institutions. Laryngoscope, 2013
Growth kinetics of candida biofilm on medical polymers: A long‐term in vitro study
Authors: Leonhard Matthias , Tobudic Selma , Moser Doris , Zatorska Beata , Bigenzahn Wolfgang , Schneider‐Stickler Berit
Published: October 2012

Objectives/Hypothesis:

Recent in vitro models simulating biofilm formation on medical polymers are restricted to only short‐term observation periods of 2 hours to 12 days.

Study Design:

The goal of this study was to develop an in vitro model to generate a long‐term polymicrobial biofilm with Candida albicans (C albicans) and Streptococcus salivarius (S salivarius) on thermoplastic medical grade silicone (TPS) and polyurethane (TPU) and continuous documentation of growth kinetics.

Methods:

Test platelets of TPS and TPU were incubated in well plates in RPMI agar at 37°C. Both microbial specimen were isolated from explanted voice prostheses and added every second day for 28 days. Afterward, only the nutrition solution has been changed regularly. Biofilm kinetics were monitored using a specially designed image analysis software to calculate the percentual surface covering of each platelet. Biofilm architecture was investigated by scanning electron microscopy (SEM). Microbial infiltration was examined by crystal violet staining and thin section microscopy.

Results:

On both materials tested, a cover of living candida biofilm could be generated over 140 days. Colonization was permanent with at least 10% surface coverage. Initially, both materials showed coverage of up to 80% followed by biofilm detachment, which could be reduced by adding planktonic microbes. SEM confirmed three‐dimensional biofilm architecture with dimorphic candida growth. Microbial material infiltration of nonhypheal types was proved in 2 TPU platelets, but not in TPS.

Conclusions:

The in vitro model presented in this study mimics in vivo events of biofilm formation on medical polymers with continuous monitoring of living biofilm kinetics. Laryngoscope, 2013
Impact of fellowship training on research productivity in academic otolaryngology
Authors: Eloy Jean Anderson , Svider Peter F. , Mauro Kevin M. , Setzen Michael , Baredes Soly
Published: October 2012

Objectives/Hypothesis:

Assessment of scholarly productivity as measured by research output is a key component of decisions regarding appointment and advancement in academic otolaryngology. An increasing number of graduating residents are pursuing postresidency fellowships, and evaluation of research productivity among these subspecialists is important in determining their role in academic otolaryngology departments. The h‐index is a reliable indicator of research productivity, as it takes into account both quantity and relevance of research contributions. Our objective was to evaluate and compare trends in research productivity among the various otolaryngology subspecialties.

Study Design:

Analysis of research productivity trends among otolaryngology subspecialties using the h‐index.

Methods:

Faculty members from 92 academic otolaryngology departments were organized by subspecialty and academic rank, and their research productivity, as measured by the h‐index, was calculated using the Scopus database.

Results:

Fellowship‐trained otolaryngologists in academic programs had higher h‐indices than non–fellowship‐trained otolaryngologists. Head and neck surgeons and otologists had significantly higher research productivity than their peers in other otolaryngology subspecialties. Analysis of the subspecialties of chairpersons indicated that 62% were either head and neck surgeons or otologists.

Conclusions:

Fellowship‐trained otolaryngologists had higher h‐indices, and faculty members trained in the subspecialties with the highest research productivity were disproportionately represented in positions of leadership within academic otolaryngology, probably reflecting the importance of research contributions in the academic advancement process, although other factors, such as educational contributions and clinical performance, may also be important factors. Laryngoscope, 2012
Hybrid Scaffolds Built From PET and Collagen as a Model For Vascular Graft Architecture
Authors: Burrows Mariana C. , Zamarion Vitor M. , Filippin‐Monteiro Fabíola B. , Schuck Desirèe C. , Toma Henrique E. , Campa Ana , Garcia Célia R. S. , Catalani Luiz H.
Published: October 2012

A hybrid material with excellent mechanical and biological properties is produced by electrospinning a co‐solution of PET and collagen. The fibers are mapped using SEM, confocal Raman microscopy and collagenase digestion assays. Fibers of different compositions and morphologies are intermingled within the same membrane, resulting in a heterogeneous scaffold. The collagen distribution and exposure are found to depend on the PET/collagen ratio. The materials are chemically and mechanically characterized and biologically tested with fibroblasts (3T3‐L1) and a HUVEC culture in vitro. All of the hybrid scaffolds show better cell attachment and proliferation than PET. These materials are potential candidates to be used as vascular grafts.

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Patterned Silk Film Scaffolds for Aligned Lamellar Bone Tissue Engineering
Authors: Tien Lee W. , Gil Eun Seok , Park Sang‐Hyug , Mandal Biman B. , Kaplan David L.
Published: October 2012

The alignment and osteogenic differentiation of MSCs on patterned silk films (PF) is investigated as a bottom‐up approach toward engineering bone lamellae. Screening PF with various groove dimensions shows that cell alignment is mediated by both the pattern width and depth. MSCs are differentiated in osteogenic medium for four weeks on flat films and on the PF that produce the best alignment. The PF support osteogenic differentiation while also inducing lamellar alignment of cells and matrix deposition. A secondary alignment effect is noted on the PF where a new layer of aligned cells grows over the first layer, but rotated obliquely to the underlying pattern. This layering and rotation of the MSCs resembles the cellular organization observed in native lamellar bone.

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Robust and Semi‐Interpenetrating Hydrogels from Poly(ethylene glycol) and Collagen for Elastomeric Tissue Scaffolds
Authors: Chan Burke K. , Wippich Caitlin C. , Wu Chia‐Jung , Sivasankar Preeti M. , Schmidt Gudrun
Published: October 2012

Here we present an injectable PEG/collagen hydrogel system with robust networks for use as elastomeric tissue scaffolds. Covalently crosslinked PEG and physically crosslinked collagen form semi‐interpenetrating networks. The mechanical strength of the hydrogels depends predominantely on the PEG concentration but the incorporation of collagen into the PEG network enhances hydrogel viscoelasticity, elongation, and also cell adhesion properties. Experimental data show that this hydrogel system exhibits tunable mechanical properties that can be further developed. The hydrogels allow cell adhesion and proliferation in vitro. The results support the prospect of a robust and semi‐interpenetrating biomaterial for elastomeric tissue scaffolds applications.

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Some identities of Green's function for the polyharmonic operator with the Navier boundary conditions and its applications
Authors: Takahashi Futoshi
Published: October 2012

We prove several integral identities for Green's function of the polyharmonic operator \documentclass{article}\usepackage{amssymb}\begin{document}\pagestyle{empty}$(-\Delta )^p, p \in \mathbb {N}$\end{document}, under the Navier boundary conditions. As an application, we prove the nondegeneracy of the critical point of the Robin function associated to the Green function on some symmetric domains.
Fast homoclinic solutions for a class of damped vibration problems with subquadratic potentials
Authors: Chen Peng , Tang X. H.
Published: October 2012

In this paper, we deal with the existence and multiplicity of homoclinic solutions of the following damped vibration problems

where L(t) and W(t, x) are neither autonomous nor periodic in t. Our approach is variational and it is based on the critical point theory. We prove existence and multiplicity results of fast homoclinic solutions under general growth conditions on the potential function. Our theorems appear to be the first such result and our results extend some recent works.
Atomic representations in function spaces and applications to pointwise multipliers and diffeomorphisms, a new approach
Authors: Scharf Benjamin
Published: October 2012

In Chapter 4 of 28 Triebel proved two theorems concerning pointwise multipliers and diffeomorphisms in function spaces \documentclass{article}\usepackage{amssymb}\begin{document}\pagestyle{empty}$B^s_{p,q}(\mathbb {R}^n)$\end{document} and \documentclass{article}\usepackage{amssymb}\begin{document}\pagestyle{empty}$F^{s}_{p,q}(\mathbb {R}^n)$\end{document}. In each case he presented two approaches, one via atoms and one via local means. While the approach via atoms was very satisfactory concerning the length and simplicity, only the rather technical approach via local means proved the theorems in full generality.

In this paper we generalize two extensions of these atomic decompositions, one by Skrzypczak (see 25) and one by Triebel and Winkelvoss (see 33) so that we are able to give a short proof using atomic representations getting an even more general result than in the two theorems in 28.
Progress in Renewable Polymers from Natural Terpenes, Terpenoids, and Rosin
Authors: Wilbon Perry A. , Chu Fuxiang , Tang Chuanbing
Published: October 2012

The development of sustainable renewable polymers from natural resources has increasingly gained attention from scientists, engineers as well as the general public and government agencies. This review covers recent progress in the field of renewable bio‐based monomers and polymers from natural resources: terpenes, terpenoids, and rosin, which are a class of hydrocarbon‐rich biomass with abundance and low cost, holding much potential for utilization as organic feedstocks for green plastics and composites. This review details polymerization and copolymerization of terpenes such as pinene, limonene, and myrcene and their derivatives, terpenoids including carvone and menthol, and rosin‐derived monomers. The future direction on the utilization of these natural resources is discussed.
Comparison between models with constant and variable diffusivity to describe water absorption by composite materials
Authors: da Silva W. P. , e Silva C. M.D.P.S. , da Silva L. D. , Lins M. A. A.
Published: October 2012

An important property of composite material is related with its water absorption characteristic. Several articles present studies about this property and, in general, in these articles an analytical solution of the diffusion equation is used to describe the process. In this case, the effective water diffusivity is considered with a constant value. However, the water penetration modifies the internal structure of the material and this can modify the effective mass diffusivity of the product. In this article, a one‐dimensional numerical solution of the diffusion equation in Cartesian coordinates is presented, enabling to consider a constant value or a variable expression for the effective water diffusivity. A comparison between the models with constant and variable diffusivity was performed and the results indicate that the model with variable diffusivity as a decreasing function of the local moisture content describes better the process than the model with constant diffusivity.
A low‐cost and reliable optical inspection system for rapid surface roughness measurements of polycrystalline thin films
Authors: Kuo C.‐C. , Huang P.‐J.
Published: October 2012

Excimer laser crystallization is a well‐known industrially used technique to produce high‐performance polycrystalline silicon thin films on the commercially available inexpensive glass substrates for the development of high‐performance low temperature polycrystalline silicon thin‐film transistors in active matrix flat panel displays. A rapid optical measurement system for rapid surface roughness measurement of polycrystalline silicon thin films was developed in this study. Two kinds of thicknesses of polycrystalline silicon thin films were used to study rapid surface roughness measurements. Six different incident angles were employed for measuring surface roughness of polycrystalline silicon thin films. The results reveal that the incident angle of 20° was found to be a good candidate for measuring surface roughness of polycrystalline silicon thin films. Surface roughness (y) of polycrystalline silicon thin films can be determined rapidly from the average value of reflected direct current voltage (x) measured by the optical system developed using the trend equation of y = –8.9854x + 91.496. The maximum measurement error rate of the optical measurement system developed was less than 5.72%. The savings in measurement time was up to 83%.
Tribological investigations of high‐performance coatings for internal combustion engines used in motor vehicles
Authors: Radu S. , Gümpel P.
Published: October 2012

The goal of this study is to investigate the tribological properties of a high‐performance coating, intended to be used for internal combustion engine components, in comparison to conventional materials. By applying the performance material, the manufacturer's objective is to extend the lifetime of the specific component of the engine. In order to highlight the benefits of using performance coatings, a direct comparison between the conventional material used in the engine (named reference material) and the performance material, was necessary. The manufacturer provided four different types of performance material, and the reference material. The study was structured in several investigation phases. First, all investigated materials underwent an optical investigation of the surface, by using a scanning electron‐microscope (SEM). In the second phase, the mechanical properties were determined, by using a roughness‐meter and hardness tester. In the third phase, the friction properties of the materials were studied on a rotating tribometer, using two lubrication types. In the last phase, by replacing the rotating tribometer with an oscillating tribometer, the friction properties of the materials, in the case of boundary lubrication, were investigated. The final objective of this study was to determine the best performance material, among the four provided by the manufacturer and to quantify the benefits of using advanced materials in comparison to classic, conventional materials.
Secondary‐Emission signal for weld formation monitoring and control in eletron beam welding (EBW)
Authors: Trushnikov D. N. , Belenki'y V. Ya. , Mladenov G. M. , Portnov N. S.
Published: October 2012

The process of emission of term electrons from the zone of effect of the electron beam are analyzed. During the experiments, the samples of stainless steel and titanium alloy were welded. Experiments were conducted to examine the spectrum of oscillations of the secondary current at various values of the specific power of the electron beam. The conducted research showed that the signal spectrum of the secondary current in electron beam welding contains a characteristic high‐frequency (15…︁25 kHz) component. It was established that the described frequency spectrum is not created by some control system in the electron beam machine and reflects the oscillations in the system – «keyhole‐plasma». Empirical density distribution of the high‐frequency signal was constructed in the amplitude range. It was shown that the parameters of the density distribution is closely linked with the nature of interaction between the beam with the metal and can be used for remote control of technology process.
An improvement of fatigue lifetime estimation by taking into account the life ratio of spectrum vs. constant amplitude loading
Authors: Hinkelmann K. , Esderts A. , Zenner H.
Published: October 2012

Betriebsfestigkeitsnachweise von Bauteilen werden häufig nach dem Nennspannungskonzept geführt. Einen zentralen Punkt bildet dabei die lineare Schadensakkumulation nach Palmgren und Miner. Statistische Auswertungen zeigen, dass diese Lebensdauerabschätzung im Mittel auf der unsicheren Seite liegt und ihre Treffsicherheit gering ist. Eine höhere Treffsicherheit ist wünschenswert. Die bisherige Verwendung von effektiven Schadenssummen stellt nur eine Anpassung des Mittelwertes dar, ohne die Treffsicherheit zu verbessern. Verbesserungen von Palmgren‐Miner original, die sich in den vergangenen Jahrzehnten in der Praxis durchgesetzt haben, sind vor allem durch Modifikationen erzielt worden, die den Amplituden unterhalb der Dauerfestigkeit eine zusätzliche Schädigung beimessen. In der vorliegenden Arbeit wird ein anderer Weg beschritten. Der in statistischen Vergleichen von rechnerischer und experimenteller Lebensdauer erkennbare Einfluss der Kollektivform und Wöhlerlinienneigung auf den Verlauf der Gaßnerlinie soll durch eine Korrekturfunktion erfasst werden. Die Überprüfung der Verbesserung der Lebensdauerabschätzung kann anhand vorliegender Versuchsreihen mit Proben aus Stahl vorgenommen werden. Weiterhin wird mithilfe von Variationsrechnungen untersucht inwieweit die bei zwei Palmgren‐Miner‐Modifikationen verwendeten Festlegungen (Haibach, Liu/Zenner) optimale Anpassungen darstellen.
Asymptotic formulations of the eigenvalues and eigenfunctions for a boundary value problem
Authors: Şen Erdoğan , Bayramov Azad
Published: October 2012

In this work, a discontinuous boundary‐value problem with retarded argument that contains a spectral parameter in the transmission conditions at the point of discontinuity is investigated. We obtained asymptotic formulas for the eigenvalues and eigenfunctions. Copyright © 2012 John Wiley & Sons, Ltd.
Continuity of the scattering function and Levinson‐type formula of Klein–Gordon equation
Authors: Karaman Özkan , Kosar Nida P.
Published: October 2012

We considered the inverse problem of scattering theory for a boundary value problem on the half line generated by Klein–Gordon differential equation with a nonlinear spectral parameter‐dependent boundary condition. We defined the scattering data, and we proved the continuity of the scattering function S(λ); in a special case, the relation for the difference of the logarithm of the scattering function, which is called the Levinson‐type formula, was obtained. Copyright © 2012 John Wiley & Sons, Ltd.
Critical extinction exponents for a polytropic filtration equation with absorption and source
Authors: Wang Yifu , Yin Jingxue
Published: October 2012

In this paper, instead of energy methods, we apply the supersolution and subsolution methods to investigate the critical extinction exponents for a polytropic filtration equation with absorption and source, and improve the results of Mu et al. (J. Math. Anal. Appl. 2012; 391:429–440). Copyright © 2012 John Wiley & Sons, Ltd.
Dietary intake and biological measurement of folate: A qualitative review of validation studies
Authors: Park Jin Young , Vollset Stein Emil , Melse‐Boonstra Alida , Chajès Véronique , Ueland Per Magne , Slimani Nadia
Published: October 2012

Folate is a nutrient of major health significance, but its dietary intake assessment is particularly complex to quantify through traditional approaches. Attempts have been made to validate dietary instruments for assessing folate intake against circulating concentration biomarkers. However, this requires careful attention on various methodological issues. We conducted a qualitative review of 17 recently published validation studies to identify these issues. The majority of the tested instruments were self‐administered food frequency questionnaires while the biomarker most frequently used was serum/plasma folate. Seasonality was not considered in most studies. Little attention was given to using updated food composition databases based on reliable chemical methods and including fortified foods and dietary supplements. Time sequence of the test instrument and the reference biomarker used was often ambiguous, and reference periods did not always match. Correlation coefficient was the metric most commonly used, and correlations between dietary folate intake and blood folate concentration varied from weak to moderate (r= 0.05–0.54). The correlations were stronger when dietary supplement use was considered, and when serum/plasma rather than red blood cell folate was used. This review summarises issues that need to be considered in future studies intending to validate instruments for dietary folate assessment against concentration biomarkers.
Structural changes and allergenic properties of β‐lactoglobulin upon exposure to high‐intensity ultrasound
Authors: Stanic‐Vucinic Dragana , Stojadinovic Marija , Atanaskovic‐Markovic Marina , Ognjenovic Jana , Grönlund Hans , van Hage Marianne , Lantto Raija , Sancho Ana I. , Velickovic Tanja Cirkovic
Published: October 2012

Scope

The aim of this work was to investigate the effects of high‐intensity ultrasound (sonication), on the structure and allergenicity of the major cow's milk allergen, beta‐lactoglobulin (BLG).

Methods and results

Structural changes upon sonication of BLG were monitored by circular dichroism spectroscopy, tryptophan emission fluorescence, hydrophobic dye and retinol binding, as well as digestibility and phenol‐oxidase cross‐linking capacity. Allergenicity was monitored in individual patients’ sera, basophil activation test, and skin prick testing in 41 cow's milk allergy patients. Uncontrolled local temperature changes induced modifications in BLG secondary structure accompanied by formation of dimers, trimers, and oligomers of BLG that were more digestible by pepsin and had reduced retinol binding. Controlled temperature conditions induced changes in secondary structure of BLG without causing formation of oligomers, or changing protein's capacity to bind retinol. Both sonicated forms of BLG had more exposed hydrophobic surfaces than native BLG and underwent facilitated cross‐linking reaction with phenol‐oxidase. Sonication had a minor effect on IgE‐binding properties of BLG.

Conclusion

Sonication‐induced structural changes in major whey allergen were not clinically significant in cow's milk allergy patients. Ultrasound can be a safe procedure for dairy processing as it maintains the nutritional value and does not increase allergenic potential of BLG.
Genome‐wide transcriptomic responses of a human isolate of Lactobacillus plantarum exposed to p‐coumaric acid stress
Authors: Reverón Inés , de las Rivas Blanca , Muñoz Rosario , López de Felipe Félix
Published: October 2012

Scope

To advance knowledge of the stress tolerance mechanisms of a probiotic Lactobacillus plantarum strain to dietary hydroxycinnamic acids and the role of gut commensal microorganisms in the bioactivation of polyphenols.

Methods and results

To understand how gut commensal microorganisms tolerate toxicity of hydroxycinnamic acids and bioactivate these compounds, we used whole genome transcriptional profiling to characterize the response of a L. plantarum human isolate during challenge with p‐coumaric acid (p‐CA). The transcriptional profile reveals a massive induction of genes involved in stress resistance and detoxification‐related functions and a global shutdown of growth‐associated processes. A specific oxidative stress response, including a large reshape of nitrogen metabolism toward methionine production, was induced, probably to counteract a p‐CA‐induced oxidative protein stress. The transcriptional datasets revealed overlapping behaviors with the response of L. plantarum to the gut environment.

Conclusion

Contact with p‐CA triggers responses that would be potentially beneficial for the intestinal function such as detoxification of dietary hydroxycinnamic acids and induction of a marked antioxidant response. Elicited responses indicated that contact with p‐CA could provide preparedness to L. plantarum for adaptation to the gut environment. This knowledge facilitates the way to design methods to improve probiotic cell survival in this habitat.
Deciphering the molecular basis of uterine receptivity
Authors: Zhang Shuang , Kong Shuangbo , Lu Jinhua , Wang Qiang , Chen Yongjie , Wang Weixiang , Wang Bingyan , Wang Haibin
Published: October 2012

Uterine receptivity is defined as a limited time period during which the uterus enters into an appropriately differentiated state that is ready for the initiation of implantation by competent blastocysts. Although various cellular aspects and molecular pathways involved in uterine receptivity have been identified by gene expression studies and genetically engineered mouse models, a comprehensive understanding of the window of uterine receptivity is still missing. This review focuses on the recent progress in this area, with particular focus on the molecular basis of stromal‐epithelial dialogue and crosstalk between the blastocyst and the uterus during implantation. A better understanding of the underlying mechanisms governing the window of uterine receptivity is hoped to generate new strategies to correct implantation failure and to improve pregnancy rates in women. Mol. Reprod. Dev. 80: 8–21, 2013. © 2012 Wiley Periodicals, Inc.
Epididymal protease inhibitor (EPPIN) is differentially expressed in the male rat reproductive tract and immunolocalized in maturing spermatozoa
Authors: Silva Erick J.R. , Patrão Marília T.C.C. , Tsuruta James K. , O'Rand Michael G. , Avellar Maria Christina W.
Published: October 2012

EPPIN (epididymal protease inhibitor; SPINLW1), an antimicrobial cysteine‐rich protein containing both Kunitz and whey acidic protein (WAP)‐type four disulfide core protease inhibitor consensus sequences, is a target for male contraception because of its critical role in sperm motility. Here, we characterized EPPIN's expression and cellular distribution in rat tissues and its in vivo regulation by androgens in the epididymis. EPPIN (mRNA and protein) was abundantly expressed in the rat testis and epididymis; we also found that the vas deferens, seminal vesicles, and brain were novel sites of EPPIN expression. PCR studies demonstrated that in addition to Sertoli cells, spermatogenic cells expressed Eppin mRNA. EPPIN was immunolocalized in Sertoli cells and spermatogenic cells (pachytene spermatocytes and round and elongated spermatids) and in epithelial cells and spermatozoa from efferent ductules and epididymis. EPPIN staining was observed on the middle and principal pieces of the flagellum of testicular spermatozoa. Epididymal spermatozoa had more intense EPPIN staining on the flagellum, and the EPPIN staining became apparent on the head and neck regions. This suggested that the EPPIN found on maturing spermatozoa was secreted primarily by the epithelial cells of the epididymis. Surgical castration down‐regulated EPPIN expression levels (mRNA and protein) in the caput and cauda epididymis, an effect reversed by testosterone replacement. Altogether, our data suggested that EPPIN expression in rats is more widespread than in humans and mice, and is androgen‐dependent in the epididymis. This species could be used as an experimental model to further study EPPIN's role in male fertility. Mol. Reprod. Dev. 79: 832–842, 2012. © 2012 Wiley Periodicals, Inc.
DNA uptake in swine sperm: Effect of plasmid topology and methyl‐beta‐cyclodextrin‐mediated cholesterol depletion
Authors: Oddi Sergio , Bernabò Nicola , Di Tommaso Monia , Angelucci Clotilde Beatrice , Bisicchia Elisa , Mattioli Mauro , Maccarrone Mauro
Published: October 2012

Sperm‐mediated gene transfer (SMGT), the ability of sperm cells to spontaneously incorporate exogenous DNA and to deliver it to oocytes during fertilization, has been proposed as an easy and efficient method for producing transgenic animals. SMGT is still undergoing development and optimization to improve the uptake efficiency of foreign DNA by sperm cells, which is a preliminary, yet critical, step for successful SMGT. Towards this aim, we developed a quantitative, real‐time PCR‐based assay to assess the absolute number of exogenous plasmids internalized into the spermatozoon. Using this technique, we found that the circular form of the DNA is more efficiently taken up than the linearized form. We also found that DNA internalization into the nucleus of porcine sperm cells is better under specific methyl‐β‐cyclodextrin (MCD)‐treated conditions, where the plasma membrane properties were altered without significantly compromising sperm physiology. These results provide the first evidence that membrane cholesterol depletion by MCD might represent a novel strategy for enhancing the ability of sperm to take up heterologous DNA. Mol. Reprod. Dev. 79: 853–860, 2012. © 2012 Wiley Periodicals, Inc.
Involvement of ABCB1 and ABCC1 transporters in sea urchin Echinometra lucunter fertilization
Authors: Silva‐Neta Helena Lima , Torrezan Elis , de Araújo Leite Jocelmo Cássio , Santi‐Gadelha Tatiane , Marques‐Santos Luis Fernando
Published: October 2012

Fertilization is an ordered sequence of cellular interactions that promotes gamete fusion to form a new individual. Since the pioneering work of Oskar Hertwig conducted on sea urchins, echinoderms have contributed to the understanding of cellular and molecular aspects of the fertilization processes. Studies on sea urchin spermatozoa reported the involvement of a plasma membrane protein that belongs to the ABC proteins superfamily in the acrosome reaction. ABC transporters are expressed in membranes of eukaryotic and prokaryotic cells, and are associated with the transport of several compounds or ions across biomembranes. We aimed to investigate ABCB1 and ABCC1 transporter activity in sea urchin spermatozoa and their involvement in fertilization. Our results indicate that Echinometra lucunter spermatozoa exhibit a low intracellular calcein accumulation (18.5% stained cells); however, the ABC blockers reversin205, verapamil, and MK571 increased dye accumulation (93.0–96.6% stained cells). We also demonstrated that pharmacologically blocking ABCB1 and ABCC1 decreased spermatozoa fertilizing capacity (70% inhibition), and this phenotype was independent of extracellular calcium. These data suggest that functional spermatozoa ABCB1 and ABCC1 transporters are crucial for a successful fertilization. Additional studies must be performed to investigate the involvement of membrane lipid homeostasis in the fertilization process. Mol. Reprod. Dev. 79: 861–869, 2012. © 2012 Wiley Periodicals, Inc.
The Educational Needs of Nurses and Allied Healthcare Professionals Caring for People with Arthritis: Results from a Cross‐Sectional Survey
Authors: Lillie Kate , Ryan Sarah , Adams Jo
Published: October 2012

Aim

The purpose of the present study was to identify the educational needs of rheumatology nurses and allied healthcare professionals (AHPs) working with people with osteoarthritis (OA) and rheumatoid arthritis (RA).

Methods

A cross‐sectional national online survey was carried out.

Results

The survey was completed by 162 health care practitioners. Seventy‐one per cent of respondents had the knowledge and skills to manage the care of a person with RA. The elements of care for which the respondents were either unsure or did not have the necessary knowledge and skills related to providing advice on exercise (37%) and pain medication (30%) to people with RA. There was a consistent tendency for respondents to be less confident in their knowledge and skills when caring for people with OA, with respondents reporting that they were either unsure or did not have the necessary knowledge and skills to advise on appropriate exercise (61%), or medication for the management of pain (45%) or the management of ongoing care (51%).

Conclusions

Current and future educational programmes on RA and OA management should provide nurses and AHPs with the opportunity to develop knowledge and skills in providing advice on exercise and pain medication. Copyright © 2012 John Wiley & Sons, Ltd.
Urgent‐SQ implant in treatment of overactive bladder syndrome: 9‐year follow‐up study
Authors: Janssen Dick A. , Farag Fawzy , Heesakkers John P.
Published: October 2012

Aims

Electrical stimulation of the posterior tibial nerve (PTN) is an established therapy for the treatment of refractory overactive bladder syndrome (OAB). The Urgent‐SQ™ is an implant that is surgically placed near the PTN and activated by an external pulse generator, allowing for “on demand” PTN stimulation, without the need for needle insertion. The current study presents results of a 9‐year, open‐label, follow‐up of eight patients to address the long term safety and efficacy of the implant.

Methods

In 2003, eight patients with refractory OAB received a Urgent‐SQ™ implant and were systematically followed up for 1 year. After that, the follow up continued as open‐label study. The seven patients who still had the implant were contacted after 9 years and evaluated with an interview, physical exam, ankle X‐ray, voiding diaries, and completed questionnaires about adverse events, performance, efficacy, safety, and quality of life (validated iQoL).

Results

Six of the seven patients still had sensory and loco‐motor responses on stimulation at 9‐year follow‐up. Three of four patients who had a successful treatment response at 1 year, still use the device. The fourth patient restarted therapy. The implants are intact with no migration and/or displacement. All patients reported easy handling of the Urgent‐SQ™. One patient reported sporadic spontaneous sensory responses. One patient reported occasional localized ankle discomfort.

Conclusions

After 9 years of clinical experience, we demonstrated that implant driven PTNS with the Urgent‐SQ™ is a safe therapy for OAB. The implant has a long lifespan and is well tolerated by patients. Neurourol. Urodynam. 32: 472–475, 2013. © 2012 Wiley Periodicals, Inc.
Multimodal iron oxide nanoparticles for hybrid biomedical imaging
Authors: Heidt Timo , Nahrendorf Matthias
Published: October 2012

Iron oxide core nanoparticles are attractive imaging agents because their material properties allow the tuning of pharmacokinetics as well as the attachment of multiple moieties to their surface. In addition to affinity ligands, these include fluorochromes and radioisotopes for detection with optical and nuclear imaging. As the iron oxide core can be detected by MRI, options for combining imaging modalities are manifold. Already, preclinical imaging strategies have combined noninvasive imaging with higher resolution techniques, such as intravital microscopy, to gain unprecedented insight into steady‐state biology and disease. Going forward, hybrid iron oxide nanoparticles will help to merge modalities, creating a synergy that will enable imaging in basic research and, potentially, also in the clinic. Copyright © 2012 John Wiley & Sons, Ltd.
Dielectric elastomers – numerical modeling of nonlinear visco‐electroelasticity
Authors: Büschel A. , Klinkel S. , Wagner W.
Published: October 2012

Dielectric elastomer actuators that can directly turn electrical energy into mechanical energy belong to the group of electroactive polymers. This type of electroelastic material exhibits large displacement characteristics and is able to change its mechanical behavior in response to the application of an electric field. Dielectric actuators are made out of elastomers which in general show viscoelastic behavior. To take this time dependent effect into account, the deformation gradient is multiplicatively decomposed. The paper is focused on the numerical modeling of soft dielectric elastomers. The theoretical foundation and the consistent finite element implementation is outlined based on the laws of electricity and elasticity. Furthermore, numerical examples of the nonlinear visco‐electroelasticity model are shown. Copyright © 2012 John Wiley & Sons, Ltd.
Older homebound women's perceived risk of being unable to reach help quickly: Influence of situations involving age‐peers
Authors: Porter Eileen J. , Lasiter Sue
Published: October 2012

The purpose of this facet of a longitudinal descriptive phenomenological study of the experience of reaching help quickly for older homebound women was to explore the personal–social context (life‐world) of situations when age‐peers had needed to reach help quickly (RHQ). Twenty‐five women aged 85–95 (13 subscribers to a personal emergency response system and 12 non‐subscribers) reported 80 peer situations. Life‐world was characterized by sharing with peers the risk of being unable to RHQ. Knowledge of peer situations had varying degrees of influence on participants' decisions to adopt and use RHQ devices. Findings support the need for healthcare professionals to explore the influences of age‐peer RHQ situations upon adoption and use of devices to RHQ by older homebound women. © 2012 Wiley Periodicals, Inc. Res Nurs Health 35:624–633, 2012