Deregulated expression of aurora kinases is not a prognostic biomarker in papillary thyroid cancer patients.

Abstract A number of reports indicated that Aurora-A or Aurora-B overexpression represented a negative prognostic factor in several human malignancies. In thyroid cancer tissues a deregulated expression of Aurora kinases has been also demonstrated, butno information regarding its possible prognostic role in differentiated thyroid cancer is available. Here, weevaluated Aurora-A and Aurora-B mRNA expression and its prognostic relevance in a series of 87 papillary thyroid cancers (PTC), with a median follow-up of 63 months. The analysis of Aurora-A and Aurora-B mRNA levels in PTC tissues, compared to normal matched tissues, revealed that their expression was either up-or down-regulatedin the majority of cancer tissues. In particular, Aurora-A and Aurora-B mRNA levels were altered, respectively, in 55 (63.2%) and 79 (90.8%) out of the 87 PTC analyzed. A significant positive correlation between Aurora-A and Aurora-B mRNAswas observed (p=0.001). The expression of both Aurora genes was not affected by the BRAF(V600E) mutation. Univariate, multivariate and Kaplan-Mayer analyses documented the lack of association between Aurora-A or Aurora-B expression and clinicopathological parameterssuch as gender, age, tumor size, histology, TNM stage, lymph node metastasis and BRAF status as well asdisease recurrences or disease-free interval. Only Aurora-B mRNA was significantly higher in T(3-4) tissues, with respect to T(1-2) PTC tissues. The data reported here demonstrate that the expression of Aurora kinases is deregulated in the majority of PTC tissues, likely contributing to PTC progression. However, differently from other human solid cancers, detection of Aurora-A or Aurora-B mRNAs is not a prognostic biomarker inPTC patients

Atomic Scale Sliding and Rolling of Carbon Nanotubes

A carbon nanotube is an ideal object for understanding the atomic scale aspects of interface interaction and friction. Using molecular statics and dynamics methods different types of motion of nanotubes on a graphite surface are investigated. We found that each nanotube has unique equilibrium orientations with sharp potential energy minima. This leads to atomic scale locking of the nanotube. The effective contact area and the total interaction energy scale with the square root of the radius. Sliding and rolling of nanotubes have different characters. The potential energy barriers for sliding nanotubes are higher than that for perfect rolling. When the nanotube is pushed, we observe a combination of atomic scale spinning and sliding motion. The result is rolling with the friction force comparable to sliding.Comment: 4 pages (two column) 6 figures - one ep

In Situ Resistance Measurements of Strained Carbon Nanotubes

We investigate the response of multi-walled carbon nanotubes to mechanical strain applied with an Atomic Force Microscope (AFM) probe. We find that in some samples, changes in the contact resistance dominate the measured resistance change. In others, strain large enough to fracture the tube can be applied without a significant change in the contact resistance. In this case we observe that enough force is applied to break the tube without any change in resistance until the tube fails. We have also manipulated the ends of the broken tube back in contact with each other, re-establishing a finite resistance. We observe that in this broken configuration the resistance of the sample is tunable to values 15-350 kW greater than prior to breaking.Comment: Submitted to Applied Physics Letter

Conductance of Distorted Carbon Nanotubes

We have calculated the effects of structural distortions of armchair carbon nanotubes on their electrical transport properties. We found that the bending of the nanotubes decreases their transmission function in certain energy ranges and leads to an increased electrical resistance. Electronic structure calculations show that these energy ranges contain localized states with significant $\sigma$-$\pi$ hybridization resulting from the increased curvature produced by bending. Our calculations of the contact resistance show that the large contact resistances observed for SWNTs are likely due to the weak coupling of the NT to the metal in side bonded NT-metal configurations.Comment: 5 pages RevTeX including 4 figures, submitted to PR

Photoionization spectroscopy of CH3C3N in the vacuum-ultraviolet range

International audienceUsing vacuum-ultraviolet (VUV) synchrotron radiation, threshold and dissociative photoionization of cyanopropyne (CH3C3N) in the gas phase have been studied from 86 000 cm−1 up to 180 000 cm−1 by recording Threshold-PhotoElectron Spectrum (TPES) and PhotoIon Yield (PIY). Ionization energies of the four lowest electronic states X̃+2E,Ã+2A1,B̃+2E and C̃+ of CH3C3N+ are derived from the TPES with a better accuracy than previously reported. The adiabatic ionization potential of CH3C3N is measured as 86872±20 cm−1. A description of the vibrational structure of these states is proposed leading to the first determination of the vibrational frequencies for most modes. The vibrational assignments of the X̃+ state are supported by density functional theory calculations. In addition, dissociative photoionization spectra have been recorded for several cationic fragments in the range 12–15.5 eV (96 790–125 000 cm−1) and they bring new information on the photophysics of CH3C3N+. Threshold energies for the cationic dissociative channels leading to CH2C3N+, CHC3N+, HC3H+, HCNH+ and CH3+ have been measured for the first time and are compared with quantum chemical calculations

Clinical characteristics and outcomes of incidental venous thromboembolism in cancer patients: insights from the Caravaggio study

Background Clinical guidelines advise similar anticoagulant treatment for symptomatic and incidental cancer-associated venous thromboembolism (VTE). We investigated clinical features and outcomes of cancer patients with incidental or symptomatic VTE randomized in the Caravaggio study. Objectives We performed a predefined sub-analysis of the Caravaggio study in order to investigate the clinical features and outcomes of incidental and symptomatic VTE in patients with cancer. The relative efficacy and safety of apixaban and dalteparin in patients with incidental and symptomatic VTE was also assessed. Methods The Caravaggio study compared apixaban to dalteparin for the 6-month treatment of cancer-associated VTE. The primary efficacy and safety outcomes were recurrent VTE and major bleeding. Results Two hundred thirty patients (20%) had incidental and 925 (80%) symptomatic VTE. Pulmonary embolism with or without deep vein thrombosis as index event, colorectal cancer, Eastern Cooperative Oncology Group (ECOG) score of 0, and locally advanced or metastatic cancer were more frequent in patients with incidental VTE. Deep vein thrombosis as index event, hematological cancer, and ECOG score of 2 were more frequent in patients with symptomatic VTE. Ten patients (4.3%) with incidental and 68 (7.4%) with symptomatic VTE had recurrent VTE (hazard ratio [HR] 0.57, 95% confidence interval [CI] 0.29-1.10). Major bleeding occurred in 12 (5.2%) patients with incidental VTE and in 33 (3.6%) patients with symptomatic VTE (HR 1.43, 95% CI 0.74-2.77). When comparing apixaban to dalteparin in patients with symptomatic and incidental VTE, the HR for recurrence was 0.73 (95% CI 0.45-1.19) and 0.41 (95% CI 0.11-1.56), respectively, and the HR for major bleeding 0.93 (95% CI 0.47-1.83) and 0.96 (95% CI 0.31-2.96), respectively. Conclusions Compared to cancer patients with symptomatic VTE, those with incidental VTE have different clinical features at presentation, with a numerically lower incidence of recurrent VTE and a numerically higher incidence of major bleeding.Thrombosis and Hemostasi

SNPs in DNA repair or oxidative stress genes and late subcutaneous fibrosis in patients following single shot partial breast irradiation

<p>Abstract</p> <p>Background</p> <p>The aim of this study was to evaluate the potential association between single nucleotide polymorphisms related response to radiotherapy injury, such as genes related to DNA repair or enzymes involved in anti-oxidative activities. The paper aims to identify marker genes able to predict an increased risk of late toxicity studying our group of patients who underwent a Single Shot 3D-CRT PBI (SSPBI) after BCS (breast conserving surgery).</p> <p>Methods</p> <p>A total of 57 breast cancer patients who underwent SSPBI were genotyped for SNPs (single nucleotide polymorphisms) in XRCC1, XRCC3, GST and RAD51 by Pyrosequencing technology. Univariate analysis (ORs and 95% CI) was performed to correlate SNPs with the risk of developing ≥ G2 fibrosis or fat necrosis.</p> <p>Results</p> <p>A higher significant risk of developing ≥ G2 fibrosis or fat necrosis in patients with: polymorphic variant <it>GSTP1 </it>(Ile105Val) (OR = 2.9; 95%CI, 0.88-10.14, <it>p </it>= 0.047).</p> <p>Conclusions</p> <p>The presence of some SNPs involved in DNA repair or response to oxidative stress seem to be able to predict late toxicity.</p> <p>Trial Registration</p> <p>ClinicalTrials.gov: <a href="http://www.clinicaltrials.gov/ct2/show/NCT01316328">NCT01316328</a></p

Hindered rolling and friction anisotropy in supported carbon nanotubes

Carbon nanotubes (CNTs) are well known for their exceptional thermal, mechanical and electrical properties. For many CNT applications it is of the foremost importance to know their frictional properties. However, very little is known about the frictional forces between an individual nanotube and a substrate or tip. Here, we present a combined theoretical and experimental study of the frictional forces encountered by a nanosize tip sliding on top of a supported multiwall CNT along a direction parallel or transverse to the CNT axis. Surprisingly, we find a higher friction coefficient in the transverse direction compared with the parallel direction. This behaviour is explained by a simulation showing that transverse friction elicits a soft 'hindered rolling' of the tube and a frictional dissipation that is absent, or partially absent for chiral CNTs, when the tip slides parallel to the CNT axis. Our findings can help in developing better strategies for large-scale CNT assembling and sorting on a surface.Comment: 8 pages, 5 figure