bluuebunny/crossref_metadata_2025_split huggingface dataset:
Local tissue temperature increase of a generic implant compared to the basic restrictions defined in safety guidelines
Authors: Kyriakou Adamos , Christ Andreas , Neufeld Esra , Kuster Niels 
Published: November 2011

AbstractThe objective of this study was to investigate if persons with implantable medical devices are intrinsically protected by the current electromagnetic safety guidelines. For inter‐laboratory comparisons, the U.S. Food and Drug Administration has defined a generic implant as consisting of an insulated wire with noninsulated tips, simulating active implants composed of a metallic case, and insulated wires with electric contacts at the tip. In this study, we determined the amplitude of the uniform electric fields induced in body tissues that cause a local increase in the tissue temperature by 1 °C in the presence of this generic implant for a wide range of frequencies and wire lengths. The field amplitudes were compared to the basic restrictions of the current exposure guidelines for both occupational and uncontrolled exposure. Results showed that a 1 °C temperature increase in the tissues around the tips of the generic implant can be reached for field strengths much smaller than 1% of those in the basic restrictions. The simulated results were validated by experimental evaluations. The impact of perfusion was investigated and was found to lead to a reduction in the local temperature peak by only 1.6–3 times. Additional simulations inside an inhomogeneous anatomical model were performed to ascertain whether similar heating as in the generic model was observed. The significant temperature elevations due to the presence of a generic implant indicate that demonstrating compliance with the basic restrictions might not be sufficient for persons with implants. Special considerations may be required, especially in the case of novel, emerging technologies that feature strong near‐fields at frequencies below 10 MHz (e.g., wireless power‐transfer systems). Bioelectromagnetics 33:366–374, 2012. © 2011 Wiley Periodicals, Inc.
Towards dynamic metabolic flux analysis in CHO cell cultures
Authors: Ahn Woo Suk , Antoniewicz Maciek R. 
Published: November 2011

AbstractChinese hamster ovary (CHO) cells are the most widely used mammalian cell line for biopharmaceutical production, with a total global market approaching $100 billion per year. In the pharmaceutical industry CHO cells are grown in fed‐batch culture, where cellular metabolism is characterized by high glucose and glutamine uptake rates combined with high rates of ammonium and lactate secretion. The metabolism of CHO cells changes dramatically during a fed‐batch culture as the cells adapt to a changing environment and transition from exponential growth phase to stationary phase. Thus far, it has been challenging to study metabolic flux dynamics in CHO cell cultures using conventional metabolic flux analysis techniques that were developed for systems at metabolic steady state. In this paper we review progress on flux analysis in CHO cells and techniques for dynamic metabolic flux analysis. Application of these new tools may allow identification of intracellular metabolic bottlenecks at specific stages in CHO cell cultures and eventually lead to novel strategies for improving CHO cell metabolism and optimizing biopharmaceutical process performance.
Towards automated production and drug sensitivity testing using scaffold‐free spherical tumor microtissues
Authors: Drewitz Maren , Helbling Marianne , Fried Nicole , Bieri Manuela , Moritz Wolfgang , Lichtenberg Jan , Kelm Jens M. 
Published: November 2011

AbstractAlthough the relevance of three‐dimensional (3‐D) culture has been recognized for years and exploited at an academic level, its translation to industrial applications has been slow. The development of reliable high‐throughput technologies is clearly a prerequisite for the industrial implementation of 3‐D models. In this study the robustness of spherical microtissue production and drug testing in a 96‐well hanging‐drop multiwell plate format was assessed on a standard 96‐well channel robotic platform. Microtissue models derived from six different cell lines were produced and characterized according to their growth profile and morphology displaying high‐density tissue‐like reformation and growth over at least 15 days. The colon cancer cell line HCT116 was chosen as a model to assess microtissue‐based assay reproducibility. Within three individual production batches the size variations of the produced microtissues were below 5%. Reliability of the microtissue‐based assay was tested using two reference compounds, staurosporine and chlorambucil. In four independent drug testings the calculated IC50 values were benchmarked against 2‐D multiwell testings displaying similar consistency. The technology presented here for the automated production of a variety of microtissues for efficacy testing in a standard 96‐well format will aid the implementation of more organotypic models at an early time point in the drug discovery process.
Gallionella spp. in trickling filtration of subsurface aerated and natural groundwater
Authors: de Vet W.W.J.M. , Dinkla I.J.T. , Abbas B.A. , Rietveld L.C. , van Loosdrecht M.C.M. 
Published: November 2011

AbstractThe growth of iron‐oxidizing bacteria, generally regarded as obligate microaerophilic at neutral pH conditions, has been reported in a wide range of environments, including engineered systems for drinking water production. This research focused on intensively aerated trickling filters treating deep anaerobic and subsurface aerated groundwater. The two systems, each comprising groundwater abstraction and trickling filtration, were monitored over a period of 9 months. Gallionella spp. were quantified by qPCR with specifically designed 16S rRNA primers and identified directly in the environmental samples using clone libraries with the same primers. In addition, enrichments in gradient tubes were evaluated after DGGE separation with general bacterial primers. No other iron‐oxidizing bacteria than Gallionella spp. were found in the gradient tubes. qPCR provided an effective method to evaluate the growth of Gallionella spp. in these filter systems. The growth of Gallionella spp. was stimulated by subsurface aeration, but these bacteria hardly grew in the trickling filter. In the uninfluenced, natural anaerobic groundwater, Gallionella spp. were only present in low numbers, but they grew extensively in the trickling filter. Identification revealed that Gallionella spp., growing in the trickling filter were phylogenetically distinct from the species found growing during subsurface aeration, indicating that the different conditions in both systems selected for niche organisms, while inhibiting other groups. The results suggest a minor direct significance for inoculation of Gallionella spp. during filtration of subsurface aerated groundwater. Biotechnol. Bioeng. 2012; 109:904–912. © 2011 Wiley Periodicals, Inc.
Multicentre observational study of the natural history of left-sided acute diverticulitis
Authors: Binda G A , Arezzo A , Serventi A , Bonelli L 
Published: November 2011

Abstract

Background
The natural history of acute diverticulitis (AD) is still unclear. This study investigated the recurrence rate, and the risks of emergency surgery, associated stoma and death following initial medical or surgical treatment of AD.

Methods
The Italian Study Group on Complicated Diverticulosis conducted a 4-year multicentre retrospective and prospective database analysis of patients admitted to hospital for medical or surgical treatment of AD and then followed for a minimum of 9 years. The persistence of symptoms, recurrent episodes of AD, new hospital admissions, medical or surgical treatment, and their outcome were recorded during follow-up.

Results
Of 1046 patients enrolled at 17 centres, 743 were eligible for the study (407 recruited retrospectively and 336 prospectively); 242 patients (32·6 per cent) underwent emergency surgery at accrual. After a mean follow-up of 10·7 years, rates of recurrence (17·2 versus 5·8 per cent; P &lt; 0·001) and emergency surgery (6·9 versus 1·3 per cent; P = 0·021) were higher for medically treated patients than for those treated surgically. Among patients who had initial medical treatment, age less than 40 years and a history of at least three episodes of AD were associated with an increased risk of AD recurrence. There was no association between any of the investigated parameters and subsequent emergency surgery. The risk of stoma formation was below 1 per cent and disease-related mortality was zero in this group. The disease-related mortality rate was 0·6 per cent among patients who had surgical treatment.

Conclusion
Long-term risks of recurrent AD or emergency surgery were limited and colectomy did not fully protect against recurrence.
Case-controlled study of critical care or surgical ward care after elective open colorectal surgery
Authors: Swart M , Carlisle J B 
Published: November 2011

Abstract

Background
Evidence for the benefit of critical care after surgery is limited. This study assessed the value of immediate admission to the critical care unit (CCU) after open colorectal surgery.

Methods
Patients aged over 45 years were screened with a cardiopulmonary exercise test to determine their anaerobic threshold. Less fit patients defined by an anaerobic threshold below 11 ml oxygen per kg per min were assigned to either critical care or surgical ward care. Those with an anaerobic threshold of 11 ml oxygen per kg per min or above were assigned to ward care. The outcome measure was the number of cardiac events.

Results
Of 153 patients who underwent exercise testing, 55 had an anaerobic threshold of at least 11 ml oxygen per kg per min (ward care) and 98 had a threshold of less than 11 ml oxygen per kg per min, of whom 39 were allocated to ward care and 51 to critical care. Median length of CCU stay was 31 (range 5–46) h. More cardiac events occurred in patients allocated to ward care (7 of 39) than in those allocated to critical care (0 of 51): absolute difference 18 (95 per cent confidence interval 10 to 26) per cent (P = 0·002). There were no cardiac events in patients with an anaerobic threshold of 11 ml oxygen per kg per min or higher.

Conclusion
Patients with an anaerobic threshold of at least 11 ml oxygen per kg per min and those with a threshold below 11 ml oxygen per kg per min managed in the CCU had fewer cardiac events.
Synthesis of economically viable biodiesel from waste frying oils (WFO)
Authors: Sharma Yogesh C. , Agrawal Shweta , Singh Bhaskar , Frómeta Amado Enrique Navarro 
Published: November 2011

AbstractIn present communication, waste frying oil (WFO) has been used as a feedstock for biodiesel synthesis. WFO, procured from a local Indian restaurant possessed an acid value of 0.84 mg KOH/g, which is low enough for single step transesterification reaction. Biodiesel (fatty acid methyl esters) was washed after transesterification reaction and the yield got lowered substantially (from 96% to 86.36%) after water washing owing to loss of esters. 30:100 vol% (methanol to oil), 0.6 wt% NaOCH3, 60°C temperature and 600 rpm agitation in 1 h reaction time was found to be optimum for transesterification reaction. 1H NMR spectrum showed a high conversion (95.19%) of fatty acids in WFO to biodiesel in 2 h reaction time. Almost complete conversion (99.68%) was attained in 2 h reaction time. © 2011 Canadian Society for Chemical Engineering
Chemical Effects in SERS of Pyrazine Adsorbed on Au–Pd Bimetallic Nanoparticles: A Theoretical Investigation
Authors: Lang Xiu‐Feng , Yin Peng‐Gang , You Ting‐Ting , Guo Lin 
Published: November 2011

AbstractChemical enhancement in surface‐enhanced Raman scattering (SERS) of pyrazine adsorbed on Au–Pd nanoclusters is investigated by using density functional theory. Changing Pd content in the bimetallic clusters enables modulation of the direct chemical interactions between the pyrazine and the clusters. The magnitude of chemical enhancement is correlated well with the induced polarizability for the complexes with low Pd content, which fails for the complexes with high Pd content. Furthermore, the dependence of chemical enhancement on cluster size and coupling is also described by the induced polarizability. Additionally, the chemical enhancement in the cluster–molecule–cluster junction is found to account for as much as 103, which suggests that a chemical mechanism might be more important than previously believed, in particular for Au–Pd bimetallic nanoparticle aggregates.
Slope effects on the spatial variations in duff moisture
Authors: Raaflaub L. D. , Valeo C. , Johnson E. A. 
Published: November 2011

ABSTRACTInvestigations were made on the influence of slope on the spatial variations in duff moisture, the decomposing organic matter of the forest floor. Relationships between duff and soil moisture along hillslopes were identified from field measurements over various moisture conditions. Results indicated that duff moisture is not related to soil moisture, nor is it controlled by a hydraulic gradient. The spatial pattern of duff moisture over a 2 week period was established along two 2 m by 60 m hillslope transects that were sampled every 3 m. Because of interception, tree proximity was found to be the primary factor that significantly influenced the spatial variation in duff moisture. As the duff dried, the influence of tree proximity decreased. The distance from the top of the hillslope was not found to be an important factor in duff moisture variability. The spatial variation in duff moisture is more prominent during periods of wetness because of the exponential nature of the duff drying curve. Copyright © 2011 John Wiley & Sons, Ltd.
IL‐23‐dependent IL‐17 drives Th1‐cell responses following Mycobacterium bovis BCG vaccination
Authors: Gopal Radha , Lin Yinyao , Obermajer Nataša , Slight Samantha , Nuthalapati Nikhil , Ahmed Mushtaq , Kalinski Pawel , Khader Shabaana A. 
Published: November 2011

AbstractThe generation of effective type 1 T helper (Th1)‐cell responses is required for immunity against intracellular bacteria. However, some intracellular bacteria require interleukin (IL)‐17 to drive Th1‐cell immunity and subsequent protective host immunity. Here, in a model of Mycobacterium bovis Bacille Calmette–Guerin (BCG) vaccination in mice, we demonstrate that the dependence on IL‐17 to drive Th1‐cell responses is a host mechanism to overcome bacteria‐induced IL‐10 inhibitory effects. We show that BCG‐induced prostaglandin‐E2 (PGE2) promotes the production of IL‐10 which limits Th1‐cell responses, while simultaneously inducing IL‐23 and Th17‐cell differentiation. The ability of IL‐17 to downregulate IL‐10 and induce IL‐12 production allows the generation of subsequent Th1‐cell responses. Accordingly, BCG‐induced Th17‐cell responses precede the generation of Th1‐cell responses in vivo, whereas the absence of the IL‐23 pathway decreases BCG vaccine‐induced Th17 and Th1‐cell immunity and subsequent vaccine‐induced protection upon M. tuberculosis challenge. Importantly, in the absence of IL‐10, BCG‐induced Th1‐cell responses occur in an IL‐17‐independent manner. These novel data demonstrate a role for the IL‐23/IL‐17 pathway in driving Th1‐cell responses, specifically to overcome IL‐10‐mediated inhibition and, furthermore, show that in the absence of IL‐10, the generation of BCG‐induced Th1‐cell immunity is IL‐17 independent.
Pim1 and Myc reversibly transform murine precursor B lymphocytes but not mature B lymphocytes
Authors: Bouquet Corinne , Melchers Fritz 
Published: November 2011

AbstractThe proto‐oncogenes Myc and Pim1, which are deregulated in many types of cancers, are known to cooperate in B lymphoma development. Here we show that overexpression of retrovirally transduced, doxycycline‐inducible Myc alone in IL‐7‐deprived, growth‐arrested pre‐B cells enhanced cell cycle entry without impairing apoptosis. Overexpression of Pim1 decreased apoptosis, but had no effect on cell cycle entry. Co‐expression of Pim1 and Myc inhibited apoptosis and led to IL‐7‐independent proliferation of the transduced pre‐B cells in vitro, while blocking their differentiation to IgM+ immature cells. Transplantation of Pim1/Myc overexpressing pre‐BI cells into B‐cell‐deficient mice expanded the pre‐B‐cell compartments up to 100‐fold within 4–8 weeks. Transformation remained dependent on the expression of both oncogenes, as removal of doxycycline in vitro and in vivo terminated proliferation and induced differentiation to IgM+ B cells. In contrast, Pim1/Myc‐transduced mature B cells that developed from the oncogene‐transduced pre‐BI cells in the absence of oncogene overexpression in vivo were not capable of long‐term proliferation after induction of Pim and Myc overexpression, neither in vivo nor in vitro, neither with nor without stimulation by polyclonal activators.
Improved sample preparation for CE‐LIF analysis of plant N‐glycans
Authors: Nagels Bieke , Santens Francis , Weterings Koen , Van Damme Els J. M. , Callewaert Nico 
Published: November 2011

AbstractIn view of glycomics studies in plants, it is important to have sensitive tools that allow one to analyze and characterize the N‐glycans present on plant proteins in different species. Earlier methods combined plant‐based sample preparations with CE‐LIF N‐glycan analysis but suffered from background contaminations, often resulting in non‐reproducible results. This publication describes a reproducible and sensitive protocol for the preparation and analysis of plant N‐glycans, based on a combination of the ‘in‐gel release method’ and N‐glycan analysis on a multicapillary DNA sequencer. Our protocol makes it possible to analyze plant N‐glycans starting from low amounts of plant material with highly reproducible results. The developed protocol was validated for different plant species and plant cells.
Isolation of metallothionein from cells derived from aggressive form of high‐grade prostate carcinoma using paramagnetic antibody‐modified microbeads off‐line coupled with electrochemical and electrophoretic analysis
Authors: Masarik Michal , Gumulec Jaromir , Sztalmachova Marketa , Hlavna Marian , Babula Petr , Krizkova Sona , Ryvolova Marketa , Jurajda Michal , Sochor Jiri , Adam Vojtech , Kizek Rene 
Published: November 2011

AbstractProstate cancer with altered zinc(II) cell metabolism is the second most frequently diagnosed cancer in developed countries. The alterations of zinc(II) metabolism can influence metabolism of other metal ions and can also be associated with the expression and translation of metal‐binding proteins including metallothioneins. The aim of this article was to optimize immunoseparation protocol based on paramagnetic beads conjugated with protein G for the isolation of metallothionein. Isolated metallothionein was determined by differential pulse voltammetry Brdicka reaction and SDS‐PAGE. Optimal conditions: antigen‐binding time – 60 min, temperature − 70°C, and buffer composition and pH – acetate buffer, pH 4.3, were determined. Under the optimized conditions, lysates from 22Rv1 prostate cancer cells treated with various concentrations of cadmium(II) and copper(II) ions were analyzed. We observed strong correlation in all experimental groups and all lysate types (r>0.83 at p<0.041) between metallothionein concentration related to viability and concentration of copper(II) ions and cadmium(II) ions in medium. Moreover, the results were compared with standard sample preparation as heat treatment and SDS‐PAGE analysis.
Simulation of flow‐flexible body interactions with large deformation
Authors: Uddin Emad , Sung Hyung Jin 
Published: November 2011

SUMMARYA modified front‐tracking method was proposed for the simulation of fluid‐flexible body interactions with large deformations. A large deformable body was modeled by restructuring the body using a grid adaptation. Discontinuities in the viscosity at the fluid‐structure interface were incorporated by distributing the viscosity across the interface using an indicator function. A viscosity gradient field was created near the interface, and a smooth transition occurred between the structure and the fluid. The fluid motion was defined on the Eulerian domain and was solved using the fractional step method on a staggered Cartesian grid system. The solid motion was described by Lagrangian variables and was solved by the finite element method on an unstructured triangular mesh. The fluid motion and the structure motion were independently solved, and their interaction force was calculated using a feedback law. The interaction force was the restoring force of a stiff spring with damping, and spread from the Lagrangian coordinates to the Eulerian grid by a smoothed approximation of the Dirac delta function. In the numerical simulations, we validated the effect of the grid adaptation on the solid solver using a vibrating circular ring. The effects of the viscosity gradient field were verified by solving the deformation of a circular disk in a linear shear flow, including an elastic ring moving through a channel with constriction, deformation of a suspended catenary, and a swimming jellyfish. A comparison of the numerical results with the theoretical solutions was presented. Copyright © 2011 John Wiley & Sons, Ltd.
Nowcasting with Google Trends in an Emerging Market
Authors: Carrière‐Swallow Yan , Labbé Felipe 
Published: November 2011

ABSTRACTMost economic variables are released with a lag, making it difficult for policy‐makers to make an accurate assessment of current conditions. This paper explores whether observing Internet browsing habits can inform practitioners about aggregate consumer behavior in an emerging market. Using data on Google search queries, we introduce an index of online interest in automobile purchases in Chile and test whether it improves the fit and efficiency of nowcasting models for automobile sales. Despite relatively low rates of Internet usage among the population, we find that models incorporating our Google Trends Automotive Index outperform benchmark specifications in both in‐sample and out‐of‐sample nowcasts, provide substantial gains in information delivery times, and are better at identifying turning points in the sales data. Copyright © 2011 John Wiley & Sons, Ltd.