bluuebunny/crossref_metadata_2025_split huggingface dataset:
X-ray Tomographic Characterization of Natural Polymer Composites and Correlation of Bulk Mechanical Properties
Authors: Pakzad Anahita , Mainwaring Paul , Heiden Patricia A. , Shahbazian Yassar Reza 
Published: October 2010

AbstractIn this research, cellulose micro-crystals (CMC) were used to reinforce a bio-polymer, polycaprolactone (PCL). Mechanical properties were tested using nanoindentation. Electron microscopy imaging and a new technique called x-ray ultra microscopy and microtomography (XuM) were used to investigate the distribution of the filler in the matrix. We could demonstrate a clear correlation between the spatial distribution of CMC-PCL composites and their nanomechanical properties.
Quantitative Mechanical Mapping of Biomolecules in Fluid
Authors: Su Chanmin , Hu Shuiqing , Hu Yan , Erina Natalia , Slade Andrea 
Published: October 2010

AbstractThough atomic force microscopy (AFM) interrogates biological materials through mechanical interactions, achieving quantitative mechanical information such as modulus and adhesion at high resolution has been a challenging task. A technology for nanometer scale mechanical property mapping, peak force tapping (PFT), was developed to achieve high resolution imaging and quantitative mechanical measurements simultaneously. PFT controls instantaneous interaction force and record force spectroscopy at each pixel to calculate mechanical properties. A feedback loop maintains a constant peak force, a local maximum point in the force spectroscopy, at the level of Pico Newtons throughout the imaging process. Such high precision force controls enable application of ultra-sharp probe to image biological samples in vitro and achieve molecular resolution in protein membranes. More importantly a full suite of mechanical properties, modulus, adhesion, energy dissipation and deformation are mapped concurrent with topographic imaging. To calculate nanomechanical properties reliably cantilever spring constant and tip shape were calibrated systematically. A method to accurately determine cantilever spring constant, capable of wafer scale cantilever calibration, was developed and tested against traceable force methods. With the knowledge of tip shape, derived from morphological dilation method using a reference sample, mechanical properties measured at the nanometer scale was compared with bench mark materials ranging from 0.7 MPa to 70 GPa. The same method was also applied to OmpG membranes, Lambda DNA strings, as well as live cells. The limitation of the measurement accuracy in biology samples will be discussed.
Statistics of Single Cell Mechanics Investigated by Atomic Force Microscopy
Authors: Hiratsuka Shinichiro , Mizutani Yusuke , Cai PingGen , Tsuchiya Masahiko , Tokumoto Hiroshi , Kawahara Koichi , Okajima Takaharu 
Published: October 2010

AbstractWe have developed the atomic force microsocpy (AFM) to measure the complex shear modulus, G*, of a large number of cells. In the AFM technique, live cells were arranged in a micro-fabricated glass substrate under the physiological conditions, and the AFM force measurement was examined in many different cells automatically. The results shown in the previous studies revealed that the frequency-dependent G* was well fitted to the so-called structural damping model, which consists of a single power-law function with a Newtonian viscous effect. However, the detail relationship has not been understood. The aim of this study was to verify the relationship between the storage and loss moduli. As results, we found that the relation between the hysteresivity (the ratio of the storage and loss moduli) and the power-law exponent was in good agreement with the structural damping model, and the result was the same as that observed in magnetic twisting cytometry (MTC), in which cells were cultured on flat substrates. This result indicated that the AFM technique presented here becomes a useful technique for precisely measuring the statistical behavior of single cell rheology.
A Novel AFM-MEA Platform for Studying the Real Time Mechano-Electrical Behavior of Cardiac Myocytes
Authors: Saenz Cogollo Jose Francisco , Tedesco Mariateresa , Martinoia Sergio , Raiteri Roberto 
Published: October 2010

AbstractWe present a novel experimental platform based on a combined Atomic Force Microscopy (AFM) and Micro-Electrode Array (MEA) set-up. We have used it to measure minimal changes in the morphological/mechanical properties of electrically active cell cultures as well as to measure the changes in the extracellular electrical activity when a single cell is stimulated by means of the AFM tip. In particular, we studied the dynamical changes in cell elasticity of embryonic rat cardiac myocytes along the contraction-relaxation cycle. Applying high load indentations, we also recorded the effects of mechanical stimulations on the cell electrophysiology. The dynamic elastic modulus of the cell related to the contraction-relaxation cycle reveals a temporal behavior that closely follows the changes in cell height. Observed values of dynamic elastic modulus at a maximum indentation depth of 1500nm varied between 8.93 ± 0.78 kPa during systolic (contraction) phase and 4.26 ± 0.47 kPa during diastolic (relaxation) phase. Induced electrophysiological responses were observed when applying loads in the range 40-150 nN. The probability P of recording an induced electrical response (P = 0.16 for a maximum load of 100nN) increased with the maximum applied load. Pulling-like stimulations due to the tip-cell adhesion could also evocate electrical responses.
Long-lifetime All-polymer Artificial Muscle Transducers
Authors: Kornbluh Roy , Wong-Foy Annjoe , Pelrine Ron , Prahlad Harsha , McCoy Brian 
Published: October 2010

AbstractThe dielectric elastomer, a particularly attractive type of electroactive polymer, uses commercial polymers such as acrylic and silicone elastomers. The technology has been limited in application by perceived lifetime issues. By addressing several lifetime issues, lifetimes of more than one million cycles, and in some cases beyond ten million cycles, were achieved with a variety of transducer configurations (including operation in generator mode) under a variety of operating conditions (including high humidity). Dielectric elastomers can produce maximum actuation strains of more than 100% and specific energy density exceeding that of known electric-field induced technology. Performance testing for dielectric elastomer actuators has typically been for peak-performance or “over-driven” conditions with short operational lifetimes (typically 100s or 1000s of cycles), particularly under conditions such as high humidity. By minimizing electric field and mechanical strain concentration factors, long lifetimes (>1 million cycles) with acrylic transducers were achieved with actuation strains as great as 40% areal strain (and up to 100% areal strain in generator mode). Actuators in a dry environment had an almost 20x increase in lifetime over actuators at ambient humidity (about 50% RH) at the same driving field conditions. Long actuation lifetimes were also achieved in a 100% RH environment and when fully submerged in salt water at reduced operating strain and field. In 100% RH, lifetimes of several million cycles were achieved at 4% strain. In underwater operation, 6 out of 11 actuators survived for >10 million cycles with an electric field limited to 32 MV/m and approximately 2% strain. The demonstrated lifecycle improvements are applicable to a variety of uses of dielectric elastomers, including haptic interface devices, pumps (implantable and external), optical positioners, and “artificial muscles” to replace small damaged muscles. Continued improvements in materials, actuator design, and packaging, combined with management of operational conditions as described here, should support new practical application of this promising technology.
Maintenance Requirements Associated With Mandibular Implant Overdentures: Clinical Results After First Year of Service
Authors: Bilhan Hakan , Geckili Onur , Mumcu Emre , Bilmenoglu Caglar 
Published: October 2010

The aim of this clinical study was to evaluate the prosthodontic maintenance requirements during the first year of service of mandibular overdentures supported by interforaminal implants and to assess the influence of attachment type, implant number, and bite force on these requirements. Fifty-nine patients treated with mandibular implant overdentures between the years 2004 and 2009 and appearing in the 12th-month recall were included in this study. The overdentures constituted 4 groups: 2 single interforaminal implants (1 group with locator and 1 group with ball attachments), 3 single interforaminal implants, 3 splinted interforaminal implants (bar), and 4 splinted interforaminal implants (bar). During the examination, prosthetic parameters such as occlusion, tissue adaptation, condition of the retentive mechanism (matrice and patrice), and the condition of the denture-bearing tissues were evaluated and recorded. No statistically significant relation was found between attachment type, bite force values, implant number, and the occurring complications except the need for relining, which was found significantly more in the ball attachments than in other attachment groups (P  =  .03). After 12 months following the overdenture insertion, there seems to be no relation between occurring complications and patient-related factors, such as maximum bite force, age, and gender, as well as factors related to the overdentures such as number and type of attachments.
Effects of Mannose-Binding Lectin Polymorphisms on Irinotecan-Induced Febrile Neutropenia
Authors: Bol Jessica M. , Jong Floris A. , Schaik Ron H. , Sparreboom Alex , Fessem Marianne A. , Geijn Fleur E. , Daele Paul L. , Verweij Jaap , Sleijfer Stefan , Mathijssen Ron H. 
Published: October 2010

AbstractObjective.Mannose-binding lectin (MBL) is important in the innate immune response. MBL2 gene polymorphisms affect MBL expression, and genotypes yielding low MBL levels have been associated with an elevated risk for infections in hematological cancer patients undergoing chemotherapy. However, these reported associations are inconsistent, and data on patients with solid tumors are lacking. Here, we investigated the effects of MBL2 genotypes on irinotecan-induced febrile neutropenia in patients with solid tumors.Patients and Methods.Irinotecan-treated patients were genotyped for the MBL2 gene. Two promoter (−550 H/L and −221 X/Y) and three exon polymorphisms (52 A/D, 54 A/B, and 57 A/C) were determined, together with known risk factors for irinotecan-induced toxicity. Neutropenia and febrile neutropenia were recorded during the first course.Results.Of the 133 patients, 28% experienced severe neutropenia and 10% experienced febrile neutropenia. No associations were found between exon polymorphisms and febrile neutropenia. However, patients with the H/H promoter genotype, associated with high MBL levels, experienced significantly more febrile neutropenia than patients with the H/L and L/L genotypes (20% versus 13% versus 5%). Moreover, patients with the HYA haplotype encountered significantly more febrile neutropenia than patients without this high MBL-producing haplotype (16% versus 4%). In the subgroup with wild-type exon polymorphisms (A/A), patients with the high MBL promoter phenotype had the highest incidence of febrile neutropenia, regardless of known risk factors.Conclusion.Patients with high MBL2 promoter genotypes and haplotypes seem more at risk for developing febrile neutropenia. If confirmed, these preliminary findings may contribute to more individualized approaches of irinotecan treatment.
Hepatitis B Reactivation and Rituximab in the Oncology Practice
Authors: Villadolid Jeryl , LaPlant Kourtney D. , Markham Merry Jennifer , Nelson David R. , George Thomas J. 
Published: October 2010

Abstract

Learning Objectives
After completing this course, the reader will be able to: Perform screening for prior hepatitis B viral exposure in all patients with hematologic malignancies who will receive rituximab as part of their therapy.Implement prophylactic antiviral therapy in patients who are positive for hepatitis B and who are being treated with rituximab.Monitor serum viral load and clinical signs of hepatic injury for at least six months following the completion of rituximab treatment in patients who are hepatitis B-sAg positive.
This article is available for continuing medical education credit at CME.TheOncologist.com
Rituximab use in hematology and oncology practice has significantly and positively improved the clinical outcomes in patients with a wide variety of B-cell lymphoproliferative disorders. However, emerging data reveal that there is a risk of viral hepatitis B reactivation in some patients treated with rituximab. Many of these cases result in treatment delays, inferior oncologic outcomes, increased morbidity, and more rarely fulminant hepatic decompensation and death. Indeed, the rituximab package insert and many clinical practice guidelines have been modified to reflect these concerns. The true incidence and mechanism of reactivation are still being elucidated. This article focuses on the current evidence that supports these recently revised clinical recommendations along with a review of the risk factors for reactivation, suggested monitoring, and preventative interventions.
Subantimicrobial‐Dose Doxycycline and Cytokine‐Chemokine Levels in Gingival Crevicular Fluid
Authors: Emingil Gülnur , Gürkan Ali , Atilla Gül , Kantarci Alpdoğan 
Published: October 2010

Background: The present randomized, double‐masked, placebo‐controlled, parallel‐arm study examines the impact of adjunctive subantimicrobial‐dose doxycycline (SDD) on the local inflammatory response through cytokine and chemokine levels in gingival crevicular fluid (GCF) samples from patients with chronic periodontitis.Methods: Forty‐six patients with chronic periodontitis received scaling and root planing with or without adjunctive SDD. GCF samples were collected and clinical parameters including probing depth, clinical attachment level, gingival index, and plaque index were recorded every 3 months for 12 months. GCF tumor necrosis factor‐α, interleukin (IL)‐6, IL‐4, IL‐10, IL‐13, IL‐17, macrophage inhibitory protein 1α, macrophage inhibitory protein 1β, monocyte chemoattractant protein 1, and regulated on activated normal T‐cell expressed and secreted protein levels were determined by xMAP multiplex immunoassay.Results: Significant improvements were observed in all clinical parameters in both groups over 12 months (P <0.0125), whereas the SDD group showed significantly better reduction in gingival index, probing depth, and gain in clinical attachment compared to the placebo group (P <0.05). Decrease in IL‐6 in the SDD group was significantly higher compared to the placebo group at 6 and 9 months in deep pockets (P <0.05), whereas tumor necrosis factor‐α was significantly reduced in moderately deep pockets (P <0.05). SDD resulted in a stable IL‐4 and IL‐10 response while reducing the monocyte chemoattractant protein 1 levels at 3 months (P <0.05).Conclusions: These results show that SDD, as an adjunct to non‐surgical periodontal therapy, stabilizes the inflammatory response by promoting the suppression of proinflammatory cytokines and increasing the anti‐inflammatory cytokines. The chemokine activity would account for the regulation of the inflammatory response to SDD therapy.
The Welfare Implications of Rent Control: A Rent-Seeking Contest Approach
Authors: Chang Yang-Ming , Sanders Shane D. 
Published: October 2010

Abstract
This paper uses a contest approach to characterize a probabilistic, non-price contest between potential consumers of rent-controlled apartments. The model extends upon the rent control model of Glaeser and Luttmer (2003) as well as the rent-seeking contributions of Hurley (1998), Dixit (1987), and Hirshleifer (1989) to consider the roles of chance and endogenously-chosen efforts in the allocation of rent-controlled apartments. Nash equilibrium effort levels for each consumer-type imply that the effort-inducing cost of rent control is greater than the misallocative cost. Further, misallocative costs are lower under the effort contest interpretation than under random allocation, as high willingness to pay consumers allocates more effort. The relationship between effort contest and misallocation influences the policys overall social cost.
Direct Recruitment of Insulin Receptor and ERK Signaling Cascade to Insulin-Inducible Gene Loci
Authors: Nelson Joel D. , LeBoeuf Renée C. , Bomsztyk Karol 
Published: October 2010

OBJECTIVE
Insulin receptor (IR) translocates to the nucleus, but its recruitment to gene loci has not been demonstrated. Here, we tested the hypothesis that IR and its downstream mitogenic transducers are corecruited to two prototypic insulin-inducible genes: early growth response 1 (egr-1), involved in mitogenic response, and glucokinase (Gck), encoding a key metabolic enzyme.

RESEARCH DESIGN AND METHODS
We used RNA and chromatin from insulin-treated rat hepatic tumor cell line expressing human insulin receptor (HTC-IR) and livers from lean and insulin-resistant ob/ob glucose-fed mice in quantitative RT-PCR and chromatin immunoprecipitation studies to determine gene expression levels and associated recruitment of RNA polymerase II (Pol II), insulin receptor, and cognate signaling proteins to gene loci, respectively.

RESULTS
Insulin-induced egr-1 mRNA in HTC-IR cells was associated with corecruitment of IR signaling cascade (IR, SOS, Grb2, B-Raf, MEK, and ERK) to this gene. Recruitment profiles of phosphorylated IR, B-Raf, MEK, and Erk along egr-1 transcribed region were similar to those of elongating Pol II. Glucose-feeding increased Gck mRNA expression in livers of lean but not ob/ob mice. In lean mice, there was glucose feeding-induced recruitment of IR and its transducers to Gck gene synchronized with elongating Pol II. In sharp contrast, in glucose-fed ob/ob mice, the Gck recruitment patterns of active MEK/Erk, IR, and Pol II were asynchronous.

CONCLUSIONS
IR and its signal transducers recruited to genes coupled to elongating Pol II may play a role in maintaining productive mRNA synthesis of target genes. These studies suggest a possibility that impaired Pol II processivity along genes bearing aberrant levels of IR/signal transducers is a previously unrecognized facet of insulin resistance.
Pharmacological Treatment of the Pathogenetic Defects in Type 2 Diabetes
Authors: Gram Jeppe , Henriksen Jan Erik , Grodum Ellen , Juhl Henning , Hansen Tony Bill , Christiansen Christian , Yderstræde Knud , Gjessing Hans , Hansen Henrik M. , Vestergaard Vibe , Hangaard Jørgen , Beck-Nielsen Henning 
Published: October 2010

OBJECTIVETo determine the effect of treatment with insulin aspart compared with NPH insulin, together with metformin/placebo and rosiglitazone/placebo. The hypothesis was that combined correction of major pathogenetic defects in type 2 diabetes would result in optimal glycemic control.RESEARCH DESIGN AND METHODSThis study was a 2-year investigator-driven randomized partly placebo-controlled multicenter trial in 371 patients with type 2 diabetes on at least oral antiglycemic treatment. Patients were assigned to one of eight treatment groups in a factorial design with insulin aspart at mealtimes versus NPH insulin once daily at bedtime, metformin twice daily versus placebo, and rosiglitazone twice daily versus placebo. The main outcome measurement was change in A1C.RESULTSA1C decreased more in patients treated with insulin aspart compared with NPH (−0.41 ± 0.10%, P &lt; 0.001). Metformin decreased A1C compared with placebo (−0.60 ± 0.10%, P &lt; 0.001), as did rosiglitazone (−0.55 ± 0.10%, P &lt; 0.001). Triple therapy (rosiglitazone, metformin, and any insulin) resulted in a greater reduction in A1C than rosiglitazone plus insulin (−0.50 ± 0.14%, P &lt; 0.001) and metformin plus insulin (−0.45 ± 0.14%, P &lt; 0.001). Aspart was associated with a higher increase in body weight (1.6 ± 0.6 kg, P &lt; 0.01) and higher incidence of mild daytime hypoglycemia (4.9 ± 7.5 vs. 1.7 ± 5.4 number/person/year, P &lt; 0.001) compared with NPH.CONCLUSIONSInsulin treatment of postprandial hyperglycemia results in lower A1C than treatment of fasting hyperglycemia, at the expense of higher body weight and hypoglycemic episodes. However, insulin therapy has to be combined with treatment of both peripheral and liver insulin resistance to normalize blood glucose, and in this case, the insulin regimen is less important.
Improving Epinephrine Responses in Hypoglycemia Unawareness With Real-Time Continuous Glucose Monitoring in Adolescents With Type 1 Diabetes
Authors: Ly Trang T. , Hewitt Jacqueline , Davey Raymond J. , Lim Ee Mun , Davis Elizabeth A. , Jones Timothy W. 
Published: October 2010

OBJECTIVE
To determine whether real-time continuous glucose monitoring (CGM) with preset alarms at specific glucose levels would prove a useful tool to achieve avoidance of hypoglycemia and improve the counterregulatory response to hypoglycemia in adolescents with type 1 diabetes with hypoglycemia unawareness.

RESEARCH DESIGN AND METHODS
Adolescents with type 1 diabetes with hypoglycemia unawareness underwent hyperinsulinemic hypoglycemic clamp studies at baseline to determine their counterregulatory hormone responses to hypoglycemia. Subjects were then randomized to either standard therapy or real-time CGM for 4 weeks. The clamp study was then repeated.

RESULTS
The epinephrine response during hypoglycemia after the intervention was greater in the CGM group than in the standard therapy group.

CONCLUSIONS
A greater epinephrine response during hypoglycemia suggests that real-time CGM is a useful clinical tool to improve hypoglycemia unawareness in adolescents with type 1 diabetes.
Schwannomatosis, sporadic schwannomatosis, and familial schwannomatosis: a surgical series with long-term follow-up
Authors: Gonzalvo Augusto , Fowler Adam , Cook Raymond John , Little Nicholas Scott , Wheeler Helen , McDonald Kerrie L. , Biggs Michael Thomas 
Published: October 2010

Object
The aim of this study was to provide disease-specific information about schwannomatosis in its different forms and to present 2 particular cases of malignant schwannomas in the context of familial schwannomatosis (FS).

Methods
The authors analyzed patients with pathologically defined schwannomas and identified those with varied forms of schwannomatosis. Each case was retrospectively analyzed for patient sex and age, number of operations and tumors excised, symptoms, location and size of tumors, extent of resection, nerve function pre- and postoperatively, complications, other nonsurgically treated tumors, malignancy, results of brain MR imaging, and follow-up data.

Results
One hundred fifty-eight patients underwent the excision of 216 schwannomas. One hundred forty-two patients presented with solitary schwannomas, 2 had neurofibromatosis Type 2 (NF2), and 14 presented with schwannomatosis. The average follow-up was 52 months. Six individuals had sporadic schwannomatosis, whereas 8 had the familial form of the disease. These 14 patients had an average age of 28.3 years at the time of disease onset (median 27.5 years) and 35.4 years at the time of the first operation (median 37 years) Thirteen of the 14 patients with schwannomatosis experienced pain as the first symptom. Eight (57%) of the 14 patients presented with at least 1 tumor in the spinal canal or attached to the spinal nerve roots. Malignant schwannomas developed in 2 patients from the same family during the follow-up.

Conclusions
Patients suffering from schwannomatosis tend to be younger than those presenting with solitary schwannomas. Therefore, individuals presenting at a young age with multiple schwannomas but not meeting the criteria for NF2 should prompt the physician to suspect schwannomatosis. Patients with schwannomatosis who report pain should be exhaustively examined. The spine is affected in the majority of patients, and MR imaging of the spine should be part of the routine evaluation. Rapid enlargement of schwannomas in the context of FS should raise suspicion of malignant transformation.