bluuebunny/crossref_metadata_2025 huggingface dataset:
Basic principles and current applications of lung ultrasonography in the intensive care unit
Authors: STEFANIDIS Konstantinos , DIMOPOULOS Stavros , NANAS Serafim
Published: October 2010

Until recently, the sonographic visualization of pulmonary and pleural diseases was considered a poorly accessible method, due to the inability of sound to penetrate air‐filled lung. Despite its limitations, lung ultrasonography is becoming an important diagnostic tool in a growing number of pathological situations such as pneumonia, atelectasis, interstitial‐alveolar syndrome, pulmonary embolism, pneumothorax and pleural effusion. The low sensitivity of CXR and the difficulties of performing CT make this technique invaluable for bedside use in the intensive care unit. Lung ultrasonography is an easily repeatable and radiation‐free technique, and therefore, an attractive imaging tool for use on a daily basis, especially in the management of critically ill patients.
Managing the aging man in Asia: A review
Authors: Tong Seng Fah , Ho Christopher , Tan Hui Meng
Published: October 2010

The aging man is becoming a major burden to Asian countries because of the current poor health status of Asian men and the aging Asian population. Life expectancy at birth for men is shorter than women by an average of 4 years in Asian countries and major causes of death are cardiovascular disease, cancers, injuries and infections. However, there are considerable variations between Asian countries because of great disparity in socioeconomic status. Male‐specific disorders, such as male sexual health and urological conditions, are other major health burdens because they have a great impact on men's quality of life. More importantly, many risk factors to the causes of mortality and morbidities, such as high‐risk behavior and smoking, can be improved with health promotion and early intervention. The current evidence suggests that the poor health status of men is the result of their poor health care utilization, negative health‐seeking behavior, the adverse social environment for men and gender‐insensitive health care delivery. However, much evidence is still needed as Asian countries have great diversity in culture, societal values and men's needs. Asian time‐tested wisdom on a balanced healthy lifestyle to longevity should be explored as potential men's health promotional programs. Taking into account Asian men's health‐care needs, a gender‐streamlined approach and man‐friendly health care delivery should be on the national agenda in managing the aging man.
Comparison of the FreeHand® robotic camera holder with human assistants during endoscopic extraperitoneal radical prostatectomy
Authors: Stolzenburg Jens‐Uwe , Franz Toni , Kallidonis Panagiotis , Minh Do , Dietel Anja , Hicks James , Nicolaus Martin , Al‐Aown Abdulrahman , Liatsikos Evangelos
Published: October 2010

Study Type – Therapy (case series) Level of Evidence 4

What’s known on the subject? and What does the study add?

The use of robotic arms for instrument and camera manipulation has been proposed for more than a decade. The current study provides a direct comparison of robotic camera movement to the conventional human camera holding assistance in real operative room setting.

OBJECTIVE

• To assess, in a prospective randomized study, the efficiency of the FreeHand® (Prosurgics Ltd, Bracknell, UK) compared to manual camera control during the performance of endoscopic extraperitoneal radical prostatectomy (EERPE).

PATIENTS AND METHODS

• Three surgeons performed 50 EERPE for localized prostate cancer. In group A (n= 25), procedures were performed with manual control of the camera by the assistant, whereas group B (n= 25) patients were treated with the assistance of the FreeHand® robotic device.

• The EERPE procedure was divided into several steps.

• Total operation duration, time for each surgical step, number of camera movements, number of movement errors, number of times the lens was cleaned, blood loss and margin status were compared.

RESULTS

• No statistically significant difference was observed in terms of patient age, preoperative prostate‐specific antigen level, Gleason score, positive cores and prostate volume.

• The average operation duration required for the performance of each step did not differ significantly between the two groups.

• Significant differences in favour of the FreeHand® camera holder were observed in case of horizontal and zooming camera movement, camera cleaning and camera errors.

• Vertical camera movements were performed significantly faster by the human assistant compared to the robotic camera holder.

• The average total operation duration was similar for both groups.

• Positive surgical margins were detected in one patient in each group (4% of the patients).

CONCLUSIONS

• A comparison of the FreeHand® robotic camera holder with human camera control during EERPE showed a similar time requirement for the performance of each step of the procedure.

• The robotic system provided accurate and fast movements of the camera without compromising the outcome of the procedure.
CLIOMETRICS AND TIME SERIES ECONOMETRICS: SOME THEORY AND APPLICATIONS
Authors: Greasley David , Oxley Les
Published: October 2010

AbstractThe paper discusses a range of modern time series methods that have become popular in the past 20 years and considers their usefulness for cliometrics research both in theory and via a range of applications. Issues such as, spurious regression, unit roots, cointegration, persistence, causality, structural time series methods, including time varying parameter models, are introduced as are the estimation and testing implications that they involve. Applications include a discussion of the timing and potential causes of the British Industrial Revolution, income ‘convergence’ and the long‐run behaviour of English real wages 1264–1913. Finally some new and potentially useful developments are discussed including the mildly explosive processes; graphical modelling and long memory.
FOR APPROPRIATENESS OR CONSEQUENCES? EXPLAINING ORGANIZATIONAL CHANGE IN ENGLISH LOCAL GOVERNMENT
Authors: ENTWISTLE TOM
Published: October 2010

New institutional theory suggests that radical organizational change is guided by a logic of appropriateness in which organizations change their structures and processes in response to changes in prevailing notions of how best to organize. Contingency theories suggests, by contrast, that organizations pursue a logic of consequentiality, trying to maximize performance by adjusting structures and processes in response to relatively tangible things like the demand for services and the state of technology. Increasingly, commentators acknowledge the importance of both logics, but how do the two fit together? This paper considers this question through an analysis of 15 cases of radical change observed in four English local authorities. While much of the existing literature seeks to theorize the circumstances in which different logics will predominate, the cases considered here suggest a need to acknowledge the intermingling of logics.
Regional Asymmetries in the Impact of Monetary Policy Shocks on Prices: Evidence from US Cities*
Authors: Fielding David , Shields Kalvinder
Published: October 2010

Variations in real exchange rates across US cities are smaller than corresponding international variations, but nevertheless substantial. We find that a proportion of these variations can be explained by asymmetric responses to federal monetary policy shocks, and that a large part of the asymmetry can be explained by city‐specific economic characteristics including the composition of local industry, bank size, house prices and the age distribution of the population.
Coeval thrusting and extension during lower crustal ductile flow – implications for exhumation of high‐grade metamorphic rocks
Authors: JAMIESON R. A. , BEAUMONT C.
Published: October 2010

Numerical models of tectonic processes in large hot orogens offer insight into the styles, controls and consequences of ductile flow of middle and lower orogenic crust. We present results from crustal‐scale thermal‐mechanical models illustrating contrasting styles of syn‐ and post‐convergent ductile flow. Crustal viscosity in the models is controlled by temperature‐dependent flow laws, scaled to represent lithological strength variations. An additional viscosity decrease at high temperature can be imposed to represent weakening during incipient partial melting. Two end‐member tectonic styles, in which lower crustal flow is driven either by gravity or tectonics, develop in response to the initial properties and evolving strength of the model crust. Homogeneous channel flow, driven by the gravitational potential energy difference between a plateau and its foreland, is characteristic of Himalayan–Tibetan (HT‐series) models with relatively weak, laterally homogeneous crust and moderately high heat production. In contrast, Grenville Orogen (GO‐series) models with relatively strong, laterally heterogeneous crust do not reach the low effective viscosity (ηeff≤1019 Pa.s) required for gravity‐driven channel flow. Instead, tectonically driven lateral flow and explusion of lower crust is triggered by underthrusting of a strong indentor. The dominant structures are ductile fold nappes that may be transported hundreds of kilometres towards the foreland. When tectonic convergence is turned off, the model orogens undergo gravitational spreading, in which ductile middle and lower crust flow laterally from the plateau towards the foreland, driving thrusting on the orogenic flanks and ductile thinning in the orogenic core. The resulting geometry can resemble that produced by syn‐convergent ductile flow, except for the development of regional‐scale normal‐sense shear zones in the post‐convergent stage. Model feasibility is tested against data from the western Grenville Orogen in Ontario. The comparison suggests that high‐grade metamorphic rocks in the orogenic core record the effects of protracted syn‐ and post‐convergent ductile flow, whereas those on the flanks record mainly post‐convergent thrusting and extension. The models suggest a number of ways to distinguish among different styles of syn‐ and post‐convergent ductile flow; metamorphic P–T–t paths alone are not diagnostic of tectonic process without additional information on crustal‐scale structure and timing. In combination with erosion, both types of flow may contribute to exhumation of regionally extensive high‐grade gneiss terranes.
Assessing the unmet treatment need in partial‐onset epilepsy: Looking beyond seizure control
Authors: Schmitz Bettina , Montouris Georgia , Schäuble Barbara , Caleo Sue
Published: October 2010

Patients with resistant epilepsy are often coprescribed multiple medications and are more likely to experience drug–drug interactions and adverse events (AEs). A new generation of antiepileptic drugs (AEDs) has been developed with improved safety/tolerability profiles. To evaluate the unmet treatment needs in epilepsy, a comprehensive search of the English‐language literature was conducted on Medline and other databases using the terms “partial epilepsy” and “focal seizure,” focusing on newer AEDs. Sixty‐nine articles were identified. Most patients experienced AEs, which were generally mild–moderate in severity. Drug–drug interactions existed for 6 of 11 AEDs for which data were available. There is evidence for depressive symptoms being associated with zonisamide, and mood‐stabilizing effects were shown for lamotrigine and pregabalin. Levetiracetam and eslicarbazepine improved cognitive function. Vigabatrin may increase the risk of developing psychosis. Health‐related quality of life (HRQoL) was inversely correlated with seizure frequency. Discontinuation rates were often high, although treatment retention improved with slower dose titration. Adjunctive therapy with newer AEDs has the potential to enhance HRQoL and treatment continuation in patients with partial epilepsy. There remains room for improvement in the management of epilepsy, and better treatments and longer‐term trials are needed to meet the special requirements of refractory patients.
Understanding the Death Benefit Switch Option in Universal Life Policies
Authors: Gatzert Nadine , Schmitt‐Hoermann Gudrun
Published: October 2010

Abstract

Universal life policies are the most popular insurance contract design in the United States. They provide either a level death benefit paying a fixed face amount or an increasing death benefit paying a fixed benefit plus the available cash value, and both types include the option to switch from one type to the other. In this article, we investigate the fact that—unlike a switch from level to increasing—a switch from an increasing death benefit to a level death benefit requires neither fees nor evidence of insurability. To assess the impact of the death benefit switch option, we develop a model framework of an increasing universal life insurance policy embedding this option. Consideration of heterogeneity with respect to mortality via a stochastic differential mortality factor enables an investigation of adverse exercise behavior. In a comprehensive simulation analysis, we quantify the net present value of the option from the insurer's perspective using risk‐neutral valuation under stochastic interest rates assuming empirical exercise probabilities. Based on our results, we provide policy recommendations for life insurers.
Risk Aversion and the Value of Risk to Life
Authors: Bommier Antoine , Villeneuve Bertrand
Published: October 2010

Abstract

The standard literature on the value of life relies on Yaari’s (1965) model, which includes an implicit assumption of risk neutrality with respect to life duration. To overpass this limitation, we extend the theory to a simple variety of preferences that are not necessarily additively separable. The enlargement we propose is relevant for the evaluation of life‐saving programs: current practice, we estimate, puts too little weight on mortality risk reduction of the young. Our correction exceeds in magnitude that introduced by the switch from the notion of number of lives saved to the notion of years of life saved.
Immunohistochemical expression of mismatch repair genes (hMSH2 and hMLH1) in hepatocellular carcinoma in Egypt
Authors: HELAL THANAA E.A. , KHAMIS NAHED S. , EL‐SHARKAWY TAREK M. , NADA OLA H. , RADWAN NEHAL A.
Published: October 2010

Helal TEA, Khamis NS, El‐Sharkawy TM, Nada OH, Radwan NA. Immunohistochemical expression of mismatch repair genes (hMSH2 and hMLH1) in hepatocellular carcinoma in Egypt. APMIS 2010; 118: 934–40.

Egypt has the highest prevalence rate of hepatitis C virus (HCV) infection in the world. HCV contributes to the development of about 70% of hepatocellular carcinoma (HCC) cases. Understanding the molecular basis of hepatocarcinogenesis is important for planning the therapeutic regimen for HCC patients. To clarify the possible role of mismatch repair (MMR) genes in HCV‐related HCC, we studied 50 HCV‐related HCC specimens (28 of which were with adjacent non‐cancerous cirrhotic liver tissue, ANCLT) and 30 specimens of chronic liver disease (CLD) with no evidence of HCC. All cases were examined immunohistochemically to demonstrate the protein expression of hMSH2 and hMLH1. Thirty‐two (64%) and 35 (70%) of the HCC cases revealed reduced expression of hMSH2 and hMLH1, respectively. Reduced expression of both the proteins was obtained in 26 (52%) of the HCC cases. The expression of hMSH2 and hMLH1 was reduced in 53.6% and 64.3% of ANCLT cases, respectively, with no significant difference between HCC and ANCLT. All 30 specimens of CLD had preserved expression of hMSH2 and hMLH1. Multivariate analysis showed that the reduced expression of hMSH2 or hMLH1 was significantly associated with higher grades of the tumor (p = 0.002 and 0.02, respectively).The relationships of these MMR genes with other clinicopathologic factors were not significant. Reduced expression of hMSH2 and hMLH1 in both HCC and ANCLT suggests that this event occurs at early stages of HCV‐related hepatocarcinogenesis. Moreover, the significant association between reduced expression of both MMR genes and poor histologic grades of the tumor claims that these proteins are involved in the process of cancer progression.
αβ versus γδ fate choice: counting the T‐cell lineages at the branch point
Authors: Kreslavsky Taras , Gleimer Michael , Garbe Annette I. , Von Boehmer Harald
Published: October 2010

Summary:  Both αβ and γδ T cells develop in the thymus from a common progenitor. Historically distinguished by their T‐cell receptor (TCR), these lineages are now defined on the basis of distinct molecular programs. Intriguingly, in many transgenic and knockout systems these programs are mismatched with the TCR type, leading to the development of γδ lineage cells driven by αβTCR and vice versa. These puzzling observations were recently explained by the demonstration that TCR signal strength, rather than TCR type per se, instructs lineage fate, with stronger TCR signal favoring γδ and weaker signal favoring αβ lineage fates. These studies also highlighted the ERK (extracellular signal regulated kinase)‐Egr (early growth response)‐Id3 (inhibitor of differentiation 3) axis as a potential molecular switch downstream of TCR that determines lineage choice. Indeed, removal of Id3 was sufficient to redirect TCRγδ transgenic cells to the αβ lineage, even in the presence of strong TCR signal. However, in TCR non‐transgenic Id3 knockout mice the overall number of γδ lineage cells was increased due to an outgrowth of a Vγ1Vδ6.3 subset, suggesting that not all γδ T cells depend on this molecular switch for lineage commitment. Thus, the γδ lineage may in fact be a collection of two or more lineages not sharing a common molecular program and thus equipollent to the αβ lineage. TCR signaling is not the only factor that is required for development of αβ and γδ lineage cells; other pathways, such as signaling from Notch and CXCR4 receptors, cooperate with the TCR in this process.
Load and lock: the molecular mechanisms of B‐lymphocyte commitment
Authors: Zandi Sasan , Bryder David , Sigvardsson Mikael
Published: October 2010

Summary:  The maturation of B‐lymphoid cells from hematopoietic stem cells in the bone marrow is a complex process under control of interplay between extrinsic and intrinsic factors. In addition to serving as a model for normal cell differentiation, disturbances in this process results in immunodeficiencies and malignancies, such as leukemia and lymphoma, making the subject of high relevance for modern medicine. Although the process of B lymphopoiesis has been under intense investigation, recent methodological developments within the area of cell sorting, genome‐wide expression, and DNA‐binding analysis has allowed for a rapid development of the understanding of B‐lymphocyte differentiation. This has suggested that the path to B‐lymphoid cell fate may be initiated by lineage priming reflected in the expression of lymphoid associated genes already in multipotent hematopoietic progenitors. Upon differentiation, the gene expression profile is changed to involve an increasing number of B‐lineage‐restricted genes linked to loss of alternative developmental potentials and B‐lineage commitment. This review focuses on the molecular regulation of early B‐lymphoid development and aims to provide an up to date summary of the current status of the research area.
From the cradle to the grave: activities of GATA‐3 throughout T‐cell development and differentiation
Authors: Hosoya Tomonori , Maillard Ivan , Engel James D.
Published: October 2010

Summary:  GATA family transcription factors play multiple vital roles in hematopoiesis in many cell lineages, and in particular, T cells require GATA‐3 for execution of several developmental steps. Transcriptional activation of the Gata3 gene is observed throughout T‐cell development and differentiation in a stage‐specific fashion. GATA‐3 has been described as a master regulator of T‐helper 2 (Th2) cell differentiation in mature CD4+ T cells. During T‐cell development in the thymus, its roles in the CD4 versus CD8 lineage choice and at the β‐selection checkpoint are the best characterized. In contrast, its importance prior to β‐selection has been obscured both by the developmental heterogeneity of double negative (DN) 1 thymocytes and the paucity of early T‐lineage progenitors (ETPs), a subpopulation of DN1 cells that contains the most immature thymic progenitors that retain potent T‐lineage developmental potential. By examining multiple lines of in vivo evidence procured through the analysis of Gata3 mutant mice, we have recently demonstrated that GATA‐3 is additionally required at the earliest stage of thymopoiesis for the development of the ETP population. Here, we review the characterized functions of GATA‐3 at each stage of T‐cell development and discuss hypothetical molecular pathways that mediate these functions.
Expanding roles for ThPOK in thymic development
Authors: Kappes Dietmar J.
Published: October 2010

Summary:  The role of the zinc finger transcription factor ThPOK (T‐helper‐inducing POZ–Kruppel‐like factor) in promoting commitment of αβ T cells to the CD4 lineage is now well established. New results indicate that ThPOK is also important for the development and/or acquisition of effector functions by other T cell subsets, including several not marked by CD4 expression, i.e. double‐negative invariant natural killer T (iNKT) cells, γδ cells, and even memory CD8+ T cells. There is compelling evidence that ThPOK expression in most or all of these cases is dependent on T‐cell receptor signaling and that differences in relative TCR signal strength/length may induce different levels of ThPOK expression. The developmental consequences of ThPOK expression vary according to cell type, which may partly reflect differences in ThPOK levels and/or in transcriptional networks between cell types.
Multilayered specification of the T‐cell lineage fate
Authors: Rothenberg Ellen V. , Zhang Jingli , Li Long
Published: October 2010

Summary:  T‐cell development from stem cells has provided a highly accessible and detailed view of the regulatory processes that can go into the choice of a cell fate in a postembryonic, stem cell‐based system. But it has been a view from the outside. The problems in understanding the regulatory basis for this lineage choice begin with the fact that too many transcription factors are needed to provide crucial input: without any one of them, T‐cell development fails. Furthermore, almost all the factors known to provide crucial functions during the climax of T‐lineage commitment itself are also vital for earlier functions that establish the pool of multilineage precursors that would normally feed into the T‐cell specification process. When the regulatory genes that encode them are mutated, the confounding effects on earlier stages make it difficult to dissect T‐cell specification genetically. Yet both the positive and the negative regulatory events involved in the choice of a T‐cell fate are actually a mosaic of distinct functions. New evidence has emerged recently that finally provides a way to separate the major components that fit together to drive this process. Here, we review insights into T‐cell specification and commitment that emerge from a combination of molecular, cellular, and systems biology approaches. The results reveal the regulatory structure underlying this lineage decision.
Different expression patterns of pAkt, NF‐κB and cyclin D1 proteins during the invasion process of head and neck squamous cell carcinoma: an in vitro approach
Authors: Giudice Fernanda Salgueiredo , Vechio Aluana Maria da Costa Dal , Abrahão Aline Corrêa , Sperandio Felipe Fornias , Pinto‐Junior Décio dos Santos
Published: October 2010

J Oral Pathol Med (2010) 40: 405–411

Background:  Several signaling pathways are involved in the progression of squamous cell carcinoma. Among them, activated PI3K/Akt may result in NF‐κB nuclear translocation, thus leading to the transcription of genes enrolled in cellular invasion and proliferation, such as cyclin D1. This study sought to evaluate the expression of pAkt, NF‐κB and cyclin D1 proteins in head and neck squamous cell carcinoma cell lines and their respective in vitro‐obtained invasive clones.

Methods:  Squamous cell carcinoma cell lines originating from the tongue, pharynx and the metastatic lymph node were submitted to an in vitro invasion assay to select invasive clones. All experimental groups were submitted to immunofluorescence and Western blot assays. Statistical analysis was performed through a Student’s t‐test with a significance level of 5%.

Results:  The pAkt and NF‐κB expression differed from cytoplasm and nucleus depending on the studied cell line. The invasive clone from the tongue presented a network‐like structure of pAkt’s cytoplasmic expression. This lineage as well as the invasive clone from pharynx also showed pAkt and NF‐κB nuclear transportation. Significant pAkt and NF‐κB increases were observed in the tongue and pharynx invasive clones. Cyclin D1 was detected in the nucleus of all studied cells and was significantly enhanced in the invasive clones from tongue and pharynx.

Conclusion:  This study suggests the participation of pAkt, NF‐κB and cyclin D1 in the invasion process of head and neck squamous cell carcinoma. Moreover, cytoplasmic pAkt network‐like structure was probably related to cytoskeleton changes presented during invasion.
Synthesis, Molecular Docking, and Biological Evaluation of Novel Triazole Derivatives as Antifungal Agents
Authors: Guan Zhongjun , Chai Xiaoyun , Yu Shichong , Hu Honggang , Jiang Yuanying , Meng Qingguo , Wu Qiuye
Published: October 2010

Twenty‐eight novel triazole derivatives (compounds 1a‐v, 2a‐f) have been synthesized for structure–activity relationship studies as antifungal agents. The compounds were designed on the basis of the structure of fluconazole and molecular modeling of the active site of the cytochrome P450 14α‐demethylase (CYP51). All of them are reported for the first time. Their chemical structures are characterized by 1H NMR, 13C NMR, LC‐MS, and elemental analysis. The antifungal activities have been evaluated in vitro by measuring the minimal inhibitory concentrations (MICs). Compounds 1a‐v exhibited higher activity against nearly all fungi tested except Aspergillus fumigatus (A. fum) than fluconazole (FCZ). The computational molecular docking experiments indicated that the inhibition of CYP51 involves a coordination bond with iron of the heme group, a hydrophilic H‐bonding region, a hydrophobic region, and a narrow hydrophobic binding cleft.
Bond strength and fracture analysis between resin cements and root canal dentin
Authors: Lopes Guilherme Carpena , Ballarin Andressa , Baratieri Luiz N.
Published: October 2010

The aim of this research is to evaluate bond strength between translucent fibre posts (White Post DC, FGM or FRC Postec Plus, Ivoclar/Vivadent) and intraradicular dentin at three different levels (cervical, middle and apical) using a dual‐cure (AllCem, FGM) or self‐curing (Multilink, Ivoclar/Vivadent) resin cement. Also, the fracture type after push‐out test was analysed under SEM. Thirty‐two extracted single‐root teeth were selected. After undergoing endodontic therapy, they were randomly divided into four groups according to their post type and resin cement. Root canals were etched using 37% phosphoric acid, and Excite DSC adhesive (Ivoclar/Vivadent) was applied in all groups. The root was sectioned to obtain nine 1‐mm‐thick slices (three per third: coronal, middle, apical). All slices were subjected to push‐out tests. Data were analysed using two‐way anova. The mean bond strengths vary from 6.6 (4.6) MPa [apical] to 11.9 (5.9) MPa [cervical]. There were no significant differences between groups. Pearson χ2‐test revealed significant differences in fracture types for all groups (P < 0.0001). The apical third had the lowest bond strengths and it was also shown to be the most critical region for luting fibre posts.
Bacterial leakage of GuttaFlow‐filled root canals compared with Resilon/Epiphany and Gutta‐percha/AH26‐filled root canals
Authors: Kangarlou Ali , Dianat Omid , Esfahrood Zeinab Rezaei , Asharaf Hengameh , Zandi Babak , Eslami Gita
Published: October 2010

The purpose of this study was to assess bacterial apical leakage in root canals obturated with GuttaFlow and compare this with the leakage of root canals obturated with Resilon/Epiphany or Gutta‐percha/AH26. A total of 55 single‐rooted human teeth were divided randomly into three experimental (n = 15) and two control groups (n = 5). Following a standardised preparation, the teeth were obturated with either GuttaFlow, Resilon/Epiphany or Gutta‐percha/AH26. A two‐chamber bacterial model using Enterococcus faecalis was employed to assess bacterial apical leakage for a period of 60 days. A Kruskal–Wallis test showed no significant differences between the seal of root canals obturated with GuttaFlow, Resilon/Ephiphany or Gutta‐percha/AH26.
Bond strength of Resilon/Epiphany compared with Gutta‐percha and sealers Sealer 26 and Endo Fill
Authors: Cecchin Doglas , Souza Matheus , Carlini‐Júnior Bruno , Barbizam Joao V.B.
Published: October 2010

This study evaluated the bond strength of Epiphany®/Resilon® to radicular dentine and compared this with that of Gutta‐percha sealed with Sealer 26 and also Endo Fill®. Fifteen human single‐rooted extracted teeth had their root canals enlarged to a standardised internal root diameter of 1.5 mm. The teeth were filled with: Group I – Epiphany®/Resilon® cones, Group II – Sealer 26®/Gutta‐percha cones and Group III – Endo Fill®/Gutta‐percha cones. Three 2 mm‐thick cross‐sections were obtained from each tooth (n = 15) and subjected to a push‐out test (1 mm min−1). The means (MPa) were compared using anova /Newman–Keuls tests. There were no statistically significant differences between Group I and Group II (P > 0.01). Both bond strengths were significantly higher than that of Group III (P < 0.01). The root canal filling system Epiphany®/Resilon® showed bond strength similar to that of Sealer 26®/Gutta‐percha. Both were higher than that of Endo Fill®/Gutta‐percha.
Effect of post‐space treatments on the push‐out bond strength and failure modes of glass fibre posts
Authors: Arısu Hacer Deniz , Kıvanç Bağdagül Helvacıoğlu , Sağlam Baran C. , Şimşek Eser , Görgül Güliz
Published: October 2010

The aim of this study was to evaluate the effect of different post‐space treatments on the push‐out bond strength and failure modes of glass fibre posts. Forty mandibular premolar roots were cut and endodontically treated. Post spaces were prepared and roots were divided into four groups. In group 1 distilled water irrigation (control), in group 2 2.25% NaOCl irrigation, in group 3 2.25% NaOCl + 17% EDTA irrigation were done and in group 4 diode laser was applied to the prepared post spaces. Scanning electron microscope (SEM) analysis was made for each group. Fibre posts were then luted with resin cement. Each root was prepared for push‐out test. Data were statistically analysed with anova (P = 0.05). After push‐out test, the failure modes were observed but not statistically analysed. There were statistically significant differences between Group 3 and Group 2 in both regions (P < 0.05), also in the middle region of Group 4 and Group 2 (P < 0.05). Cervical root segments showed higher bond strengths than middle ones in all groups (P < 0.05). The highest bond strength values were obtained from NaOCl/EDTA and the lowest bond strength values were obtained from NaOCl for both regions.
Functional activity of Pat‐1 (Slc26a6) Cl−/HCO3− exchange in the lower villus epithelium of murine duodenum
Authors: Walker N. M. , Simpson J. E. , Hoover E. E. , Brazill J. M. , Schweinfest C. W. , Soleimani M. , Clarke L. L.
Published: October 2010

Aims:  The apical membrane anion exchanger putative anion transporter‐1 (Pat‐1) is expressed at significant levels in the lower villus epithelium of murine duodenum. However, previous studies of Cl−/HCO3− exchange in the lower villus have failed to demonstrate Pat‐1 function. Those studies routinely included luminal glucose which induces Na+‐coupled glucose transport and acidifies the villus epithelium. Since Pat‐1 has been proposed to be an electrogenic 1Cl−/2HCO3− exchanger, membrane depolarization or cell acidification during glucose transport may obscure Pat‐1 activity. Therefore, we investigated the effects of luminal glucose on Cl−IN/HCO3−OUT exchange activity in the lower villus epithelium.

Methods:  Cl−IN/HCO3−OUT exchange of villus epithelium in duodenal mucosa from Pat‐1 knockout (KO), Slc26a3 [down‐regulated in adenoma (Dra)] KO, cystic fibrosis transmembrane conductance regulator (Cftr) KO and wild‐type (WT) littermate mice was measured using the pH‐sensitive dye 2′,7′‐bis‐(2‐carboxyethyl)‐5‐(and‐6)‐carboxyfluorescein. Short‐circuit current (Isc) was measured in Ussing chambers.

Results:  During glucose absorption, Cl−IN/HCO3−OUT exchange in the lower villus epithelium was abolished in the Dra KO and unaffected in the Pat‐1 KO relative to WT. However, during electroneutral mannose absorption or electrogenic α‐D‐methyl glucoside absorption, Cl−IN/HCO3−OUT exchange was reduced in both Pat‐1 KO and Dra KO villi. Exposure to high [K+] abolished Cl−IN/HCO3−OUT exchange in the Dra KO but not the Dra/Cftr double KO epithelium, suggesting that Pat‐1 activity is little affected by membrane depolarization except in the presence of Cftr.

Conclusions:  The metabolic and electrogenic activity of glucose transport obscures Cl−IN/HCO3−OUT exchange activity of Pat‐1 in the lower villus. The inhibitory effects of membrane depolarization on Pat‐1 Cl−IN/HCO3−OUT exchange may require concurrent membrane association with Cftr.
Routine calcium measurement is not necessary after most thyroid surgeries: a prospective clinical study
Authors: Quinn E.M. , Neary P.M. , O’Connor O.J. , Shafiq A. , Kelly J. , Redmond H.P.
Published: October 2010

Clin. Otolaryngol. 2010, 35, 468–473

Objectives:  Calcium levels are often measured to diagnose postoperative hypocalcaemia following thyroidectomy. The aims of this study were to (i) prospectively determine the incidence of symptomatic and biochemical hypocalcaemia following thyroidectomy, (ii) to identify if any associations exist between hypocalcaemia, type of surgery, histological diagnosis, specimen size/weight and the presence of histological parathyroid tissue and (iii) to evaluate the necessity of routine measurement of calcium levels following all thyroidectomies.

Design:  Prospective clinical study.

Settings:  University teaching hospital.

Participants:  Eighty‐six patients presenting consecutively for thyroid surgery.

Outcome measures:  Type of surgery, indications, perioperative calcium levels, symptoms of hypocalcaemia and histology were documented.

Results:  Fifty‐four patients underwent thyroid lobectomy and isthmusectomy, 19 underwent total and 13 completion thyroidectomy. Significantly, no patient undergoing thyroid lobectomy developed hypocalcaemia versus 26% of total thyroidectomies (P = 0.001) and 23% of completion thyroidectomies (P = 0.006). All eight patients with hypocalcaemia required treatment. Seven were initially identified clinically. Logistic regression analysis revealed that operation type was the only independent risk factor for developing hypocalcaemia (P = 0.021).

Conclusions:  No patient developed hypocalcaemia following thyroid lobectomy and isthmusectomy. Considering the majority (63%) of thyroid surgeries were lobectomies, most patients tested appear low risk for hypocalcaemia. Definitive prediction of hypocalcaemia postoperatively remains a challenge. However, our results suggest that analysing calcium levels routinely following thyroid lobectomy is unwarranted.
Correlation between acoustic rhinometry and subjective nasal patency during nasal challenge test in subjects with suspected occupational rhinitis; a prospective controlled study
Authors: Castano R. , Trudeau C. , Ghezzo H.
Published: October 2010

Clin. Otolaryngol. 2010, 35, 462–467

Objectives:  To assess the correlation between acoustic rhinometry and visual analogue scale endpoints in the context of nasal challenge with occupational agents.

Design:  Prospective controlled study.

Setting:  University teaching hospital.

Participants:  Sixty‐seven subjects with a history of work‐related rhinitis and asthma symptoms.

Main outcomes measures:  Subjects underwent nasal challenge with control and specific agent on consecutive days. Nasal congestive response to challenge was monitored by acoustic rhinometry and visual analogue scale.

Results:  Results showed no correlation between visual analogue scale and acoustic rhinometry measurements at baseline on the control (r = −0.13, P = 0.3) and active (r = 0.14, P = 0.2) challenge days. No correlation was found between acoustic rhinometry and visual analogue scale when analysing all measurements obtained at all times after challenge with the control and active agent (control: r = 0.09, P = 0.04; active: r = 0.001, P = 0.9). The correlation between acoustic rhinometry and visual analogue scale was good and significant (r = −0.62, P = <0.01) when the analysis was restricted to cases showing a decrease in nasal volume >40% from baseline values.

Conclusions:  We showed that the correlation between acoustic rhinometry and subjective nasal patency was poor on steady conditions. However, a significant correlation was observed in those cases showing a greater nasal congestive response after challenge measured by acoustic rhinometry.
Novel anti‐fatty acid synthase compounds with anti‐cancer activity in HER2+ breast cancer
Authors: Oliveras G. , Blancafort A. , Urruticoechea A. , Campuzano O. , Gómez‐Cabello D. , Brugada R. , López‐Rodríguez M. L. , Colomer R. , Puig T.
Published: October 2010

Fatty acid synthase (FASN) expression and activity has emerged as a common phenotype in most human carcinomas, including breast cancer, and its expression is tightly linked to HER2 signaling pathways. The development of inhibitors of FASN activity has consequently appeared as a novel antitarget modality for treating cancer. However, the clinical use of FASN inhibitors, such as cerulenin, C75, and epigallocatechin 3‐gallate (EGCG), is limited by anorexia and induced body weight loss or by its low in vivo potency and stability. Here, we summarize the design and development of G28UCM, the lead‐compound of a novel family of synthetic FASN inhibitors, with both in vitro and in vivo activity in a human breast cancer model of FASN+ and HER2+.
Primary trastuzumab resistance: new tricks for an old drug
Authors: Wilken Jason A. , Maihle Nita J.
Published: October 2010

Trastuzumab is the first Food and Drug Administration (FDA)‐approved therapeutic targeting a HER‐family receptor tyrosine kinase (HER2/ErbB2/neu). Although trastuzumab is effective in the treatment of HER2‐positive breast cancer, a substantial proportion of patients will not respond to trastuzumab‐based regimens (primary resistance), and those who do respond will often lose clinical benefits (i.e., secondary resistance). Although multiple mechanisms underlying the development of secondary trastuzumab resistance have been identified, few studies have specifically examined the basis of primary trastuzumab resistance. Here, we review these studies, which together demonstrate that trastuzumab induces phenotypic changes in tumor cells, even when they are not growth inhibited by trastuzumab, including changes in gene expression. These changes have important clinical implications, including the sensitization of malignant cells to other therapeutic drugs. In light of these observations, we propose that the conventional definition of resistance as it pertains to trastuzumab and, perhaps, to other targeted therapeutics, may require revision. The results of these studies will be useful in informing the direction of future basic and clinical research focused on overcoming primary trastuzumab resistance.
Breast cancer genomics: normal tissue and cancer markers
Authors: Schummer Michèl , Beatty David , Urban Nicole
Published: October 2010

Mammography is a powerful screening tool for early detection of breast cancer, but it has limitations in terms of both specificity and sensitivity. Imaging tools such as MRI that complement mammography are too costly to serve as first‐line screens. Recently, progress has been made on blood markers, particularly microRNAs and proteins. There are new methods for protein marker discovery directly in blood, but they are limited in the number of patients that can be examined. An alternative is to discover markers as transcripts in tissues, followed by development of blood protein tests for those that perform best. To identify genes that are overexpressed in malignancy it is paramount to include normal control tissues from healthy individuals. Here we report the identification of potential breast cancer markers, including some that are overexpressed in aggressive disease.
MicroRNAs in cancer: personalizing diagnosis and therapy
Authors: Nana‐Sinkam S. Patrick , Fabbri Muller , Croce Carlo M.
Published: October 2010

MicroRNAs (miRNAs) are 19–24nt noncoding RNAs that have been implicated in the pathogenesis of both solid and hematological malignancies. Frequently located in fragile chromosomal regions, miRNAs are essential to key biological functions, such as cellular differentiation, apoptosis, and growth. miRNAs may serve as either tumor suppressors or oncogenes. As a result, they have the potential to serve as both biomarkers and therapeutic agents in cancer. Based on our presentation at the recent Towards Personalized Cancer Medicine conference held in Barcelona, Spain, May 19–21, 2010, we provide an overview of the current knowledge of miRNA deregulation in solid and hematological malignancies and their application as biomarkers of disease.
A Simple Alternative to the Routh-Hurwitz Criterion for Symmetric Systems
Authors: Moran T. J.
Published: November 2010

A necessary and sufficient condition for the asymptotic stability of damped, linear, symmetric, multidegree of freedon systems is given. The condition is easily applied if the principal coordinates for the undamped system are known. The stability properties of such systems which are not asymptotically stable are investigated and the result is extended to gyroscopic systems.
A New Method for Computing Axisymmetric Buckling of Spherical Caps
Authors: Thurston G. A.
Published: November 2010

A modification of Newton’s method is applied to the solution of the nonlinear differential equations for clamped, shallow spherical caps under uniform pressure. The linear form of Newton’s method or quasi-linearization breaks down at limit points of the differential equations. A simplified “quadratic form” is derived in the paper and shown to be satisfactory for continuing the solution past the limit point and into the postbuckling region. Results for the buckling pressures defined by the limit points agree with published results for perfect caps. New results are presented for imperfect caps that check experiment.
On the Nonlinear Vibrations of Free-Free Beams
Authors: Hu Kuo-Kuang , Kirmser Philip G.
Published: November 2010

A nonlinear partial differential equation which describes the natural free-free vibrations of beamlike structures is derived, and then solved approximately by reduction to a nonlinear ordinary differential equation through the use of the Duffing and Ritz-Kantorovich methods. This ordinary differential equation, which is a nonlinear eigenvalue problem, is then solved by perturbation and shooting methods. The solutions show that higher modes of vibration are not possible for the nonlinear vibration.
Flow in a Gas-Operated Rifle
Authors: Spurk J. H.
Published: November 2010

The unsteady gas flow in the actuation system of a gas-operated rifle is treated by perturbation analysis. A uniformly valid solution in time is found by matching the solution for early time with a quasi-steady solution. The predictions of the perturbation analysis are compared with experimental results from two rifles and satisfactory agreement is noted.
Characteristic Exponents and Stability of Hill’s Equation
Authors: Nayfeh Ali Hasan
Published: November 2010

The methods of strained parameters and multiple scales are used to determine a second-order uniform expansion for the solutions of Hill’s equation near the transition curves. Second-order explicit expansions are presented for the characteristic exponents and the transition curves.
Propagation of Stress Gradient Through an Inclusion—Part 1
Authors: Ting T. C. T. , Chou Shun-Chin
Published: November 2010

This is the first of a two-part study on the propagation of stress gradient in composite materials. Both the plane-strain and axisymmetric motions are considered. In this paper, the reflection and transmission coefficients are derived for the stress, the stress gradient, and the higher-order derivatives of stress at an interface between two elastic media. It is shown that while the reflection and transmission of the stress do not depend on the geometries of the incident wave front and the interface boundary, the reflection and transmission of the stress gradient, and the higher-order derivatives of stress do depend on these geometries. Explicit expressions are derived for the reflection and transmission of the stress gradient in terms of the radii of curvatures of the incident wave front and the interface boundary.
Modes and Frequencies of Transversely Isotropic Slightly Curved Timoshenko Beams
Authors: Rossettos J. N. , Squires D. C.
Published: November 2010

An analysis of the vibration of transversely isotropic Timoshenko beams, which have small constant initial curvature, is presented, and a closed-form general solution to the governing equations is derived. Natural modes and frequencies are determined for both clamped and simply supported end conditions, and comparisons are made. The combined effects of initial curvature, transverse shear deformation, and boundary conditions are evaluated and discussed. Specifically, it is shown in what manner the clamped beam tends to be more sensitive to shear deformation than the simply supported beam, and how initial curvature reduces the difference. Calculations also show how, in cases where shear deformation becomes more important, the initial curvature has a correspondingly smaller influence on the results.
Initial-Value Method for a Pseudoplastic Fluid in a Laminar Boundary Layer Over a Porous Flat Plate With Suction
Authors: Nath G.
Published: November 2010

The effect of finite suction velocity on the Blasius boundary-value problem, as generalized for power-law non-Newtonian fluids, has been studied by reducing the problem to an initial-value problem which can then be easily solved numerically. The initial-value method seems to be more efficient than the other known methods and the computer time required for the solution is also much less.
Stresses and Strains in a Disk With Variable Modulus of Elasticity
Authors: Durelli A. J. , Machida S.
Published: November 2010

A transparent material with variable modulus of elasticity has been manufactured. It exhibits good photoelastic properties, and can also be strain analyzed by printing gratings on its surface and producing the moire´ effect. The new material is used to stress and strain analyze a disk of variable E, subjected to diametral compression. The discussion of the results obtained suggests that the stress distribution in the disk of variable E is practically the same as the stress distribution in the homogeneous disk. It also indicates that the strain fields in both cases are very different, but that it is possible, approximately, to obtain the strain field from the stress field for an homogeneous material using the value of E at every point, and Hooke’s law.