Prognostic significance of human pituitary tumor-transforming gene immunohistochemical expression in differentiated thyroid cancer

Context: Human securin pituitary tumor-transforming gene (hPTTG) is overexpressed in a variety of primary neoplasias, including differentiated thyroid cancer (DTC). Objective: The objective of this study was to examine the immunohistochemical expression of hPTTG in DTC and its association with known prognostic factors. Design: hPTTG expression was analyzed by immunostaining on paraffin-embedded tissues. Clinical data were used to determine any associations between the expression of hPTTG and prognostic variables of DTC. A median follow-up of 43 months allowed us to analyze the persistence of disease and the response to radioiodine therapy. Setting: The study was conducted at a tertiary university hospital. Patients: Ninety-five patients undergoing surgical resection for DTC (n = 60) or benign nodular thyroid disease (n = 35) were studied. Main Outcome Measure: The main outcome measure was the association between hPTTG expression and prognostic factors in DTC. Results: Among DTC cases, 21 (35%) had low and 39 (65%) had high hPTTG immunostaining. Adjacent nonneoplastic thyroid tissue was largely unstained. Among benign nodular thyroid disease cases, immunostaining was detected focally in eight (22.8%). A significant association was found between hPTTG expression and the presence of nodal (P < 0.01) or distant metastases (P < 0.05). A significant association with TNM was also found, because 83.3% of advanced TNM stages showed elevated hPTTG (P < 0.05). The association between hPTTG overexpression and decreased radioiodine uptake during follow-up was also significant (P < 0.05). The expression levels of hPTTG were confirmed as an independent prognostic factor for persistent disease (relative risk, 3.0; 95% confidence interval, 1.1-8.7; P < 0.05). Conclusions: Immunohistochemical analysis of hPTTG is of potential value in the determination of tumor aggressiveness in DTC.Peer Reviewe

Piezoelectric characterization of ain thin films on silicon substrates

The electric field induced deformations of thin piezoelectric, aluminium nitride (AlN) layers, on top ofa silicon substrate, were studied by numerical calculations and interferometric measurements. Our calculationby finite element method demonstrates that substrate deformation under the top electrode may be comparableto the deformation in the thin AlN layer, for a given applied voltage. Simulations also show the effect of aclamped or free substrate condition and the relative contributions of d33 and d31 piezoelectric constants. ALaser scanning vibrometry technique was used to measure deformations in the top surface with sub-picometervertical resolution. By comparing calculations and experimental data, quantitative information about both d31and d33 constants can be obtained

Simulation and laser vibrometry characterization of piezoelectric AlN thin films

In this paper, the electric field induced deformations of sputter-deposited piezoelectric aluminum nitride thin films sandwiched between electrodes on top of a silicon substrate are studied by numerical calculations and scanning laser interferometric measurements. In our calculations based on the finite element method, the results show the displacement of the top and bottom surfaces of both the thin film and the substrate, for either a free or a perfectly clamped structure. The confirmation that the bottom surface of the film is deformed reveals the limitations of techniques that only access the top surface, as well as the double-beam interferometric configuration, under specific conditions. In addition, the simulations demonstrate the dependence of the displacements on the size of the upper electrode and the contribution of the transverse piezoelectric coefficient d31 to the features of the displacement profiles. A laser scanning vibrometry technique was used to measure deformations on the top surface with subpicometer vertical resolution. By comparing the calculated and the experimental displacement profiles, an advanced approach is discussed to obtain accurate quantitative information of both coefficients d31 and d33

On the soliton width in the incommensurate phase of spin-Peierls systems

We study using bosonization techniques the effects of frustration due to competing interactions and of the interchain elastic couplings on the soliton width and soliton structure in spin-Peierls systems. We compare the predictions of this study with numerical results obtained by exact diagonalization of finite chains. We conclude that frustration produces in general a reduction of the soliton width while the interchain elastic coupling increases it. We discuss these results in connection with recent measurements of the soliton width in the incommensurate phase of CuGeO_3.Comment: 4 pages, latex, 2 figures embedded in the tex

Downregulation of protein tyrosine phosphatase PTPL1 alters cell cycle and upregulates invasion-related genes in prostate cancer cells

The final publication is available at link.springer.comPTPL1, a non-receptor type protein tyrosine phosphatase, has been involved in the regulation of apoptosis and invasiveness of various tumour cell types, but its role in prostate cancer remained to be investigated. We report here that downregulation of PTPL1 by small interfering RNA in PC3 cells decreases cell proliferation and concomitantly reduces the expression of cell cycle-related proteins such as cyclins E and B1, PCNA, PTTG1 and phospho-histone H3. PTPL1 downregulation also increases the invasion ability of PC3 cells through Matrigel coated membranes. cDNA array of PTPL1-silenced PC3 cells versus control cells showed an upregulation of invasion-related genes such as uPA, uPAR, tPA, PAI-1, integrin α6 and osteopontin. This increased expression was also confirmed in PTPL1-silenced DU145 prostate cancer cells by quantitative real time PCR and western blot. These findings suggest that PTPL1 is an important mediator of central cellular processes such as proliferation and invasion. © 2012 Springer Science+Business Media B.V.This work was supported by Grants from the Ministerio de Ciencia e Innovación, Instituto de Salud Carlos III, Spain (FIS PI10/02026 and SAF2008-05046-C02-02), ISCIIIRETIC-RD06/0020-FEDER, Consejería de Salud (PI-2009-0589, AI-2010-003 to M.A.J.), and Consejería de Innovación, Ciencia y Empresa (CTS-6243), Junta de Andalucía (06/189, PI-2009-0589, and AI-2010-003 to M. A. J.). C. C. was supported by a pre-doctoral Grant from the Spanish Ministerio de Educación (F.P.I.: BES200612419) co-financiated by Fondo Social Europeo. C. S. was supported by a contract from Instituto de Salud Carlos III/FIS and Fundación Progreso y Salud, Consejería de Salud, Junta de Andalucía, Miguel Servet Program.Peer Reviewe

Development of solar radiation prediction models using machine learning techniques

[Resumen] La creciente demanda de paneles solares en los últimos años ha hecho que cada vez más empresas se dediquen por completo a la instalación de paneles fotovoltaicos o captadores solares con el fin de aprovechar al máximo la energía solar. Ya sea para un huerto solar o para conseguir edificios más eficientes energéticamente, el disponer de predicciones de radiación solar y, por tanto, de la producción de electricidad o de calor, facilita la toma de decisiones y permite realizar una gestión óptima de la producción y demanda de energía. Sin embargo, la predicción de la radiación solar es un desafío importante debido, entre otros factores, a su alta variabilidad espacial y temporal y a la influencia de las condiciones atmosféricas. Este trabajo presenta una comparación de modelos de predicción de radiación solar desarrollados mediante técnicas de aprendizaje automático utilizando datos históricos de la Plataforma Solar de Almería. Los resultados obtenidos resultan prometedores ya que, en la mayoría de los casos, se han obtenido errores inferiores al 12 %.[Abstract] In recent years, the growing demand for solar panels has led an increasing number of companies to focus on installing both photovoltaic panels and solar collectors in order to take advantage of solar energy. Whether it is a solar farm or an energy-efficient building, the availability of predictions of solar radiation, and therefore of electricity and heat production, facilitates decision making and allows the development of optimal management strategies for energy production and demand. However, the prediction of solar radiation is a major challenge due to, among other factors, its high spatial and temporal variability and the influence of atmospheric conditions. This paper presents a comparison of solar radiation prediction models developed using machine learning techniques and historical data from the Solar Platform of Almería. The results obtained are promising since, in most cases, an error less than 12% has been obtained.Ministerio de Ciencia e Innovación; TED2021-131655B-I0

Methylation alterations are not a major cause of PTTG1 missregulation

Background: On its physiological cellular context, PTTG1 controls sister chromatid segregation during mitosis. Within its crosstalk to the cellular arrest machinery, relies a checkpoint of integrity for which gained the over name of securin. PTTG1 was found to promote malignant transformation in 3T3 fibroblasts, and further found to be overexpressed in different tumor types. More recently, PTTG1 has been also related to different processes such as DNA repair and found to trans-activate different cellular pathways involving c-myc, bax or p53, among others. PTTG1 over-expression has been correlated to a worse prognosis in thyroid, lung, colorectal cancer patients, and it can not be excluded that this effect may also occur in other tumor types. Despite the clinical relevance and the increasing molecular characterization of PTTG1, the reason for its up-regulation remains unclear. Method: We analysed PTTG1 differential expression in PC-3, DU-145 and LNCaP tumor cell lines, cultured in the presence of the methyl-transferase inhibitor 5-Aza-2'-deoxycytidine. We also tested whether the CpG island mapping PTTG1 proximal promoter evidenced a differential methylation pattern in differentiated thyroid cancer biopsies concordant to their PTTG1 immunohistochemistry status. Finally, we performed whole-genome LOH studies using Affymetix 50 K microarray technology and FRET analysis to search for allelic imbalances comprising the PTTG1 locus. Conclusion: Our data suggest that neither methylation alterations nor LOH are involved in PTTG1 over-expression. These data, together with those previously reported, point towards a post-transcriptional level of missregulation associated to PTTG1 over-expression.This project was funded by The Fundación de Investigación Biomédica Mutua Madrileña Automovilista. Neocodex have been partially funded by the Ministerio de Educación y Ciencia of Spain (FIT-010000-2004-69, PTQ04-1-0006, PTQ2003-0549, PTQ2003-0546 and PTQ2003-0783). MAJ was also supported by SAF2005- 07713-C03-03 and CS by FIS 06/757

Rapid Suppression of the Spin Gap in Zn-doped CuGeO_3 and SrCu_2O_3

The influence of non-magnetic impurities on the spectrum and dynamical spin structure factor of a model for CuGeO$_3$ is studied. A simple extension to Zn-doped ${\rm Sr Cu_2 O_3}$ is also discussed. Using Exact Diagonalization techniques and intuitive arguments we show that Zn-doping introduces states in the Spin-Peierls gap of CuGeO$_3$. This effect can beunderstood easily in the large dimerization limit where doping by Zn creates ``loose'' S=1/2 spins, which interact with each other through very weak effective antiferromagnetic couplings. When the dimerization is small, a similar effect is observed but now with the free S=1/2 spins being the resulting S=1/2 ground state of severed chains with an odd number of sites. Experimental consequences of these results are discussed. It is interesting to observe that the spin correlations along the chains are enhanced by Zn-doping according to the numerical data presented here. As recent numerical calculations have shown, similar arguments apply to ladders with non-magnetic impurities simply replacing the tendency to dimerization in CuGeO$_3$ by the tendency to form spin-singlets along the rungs in SrCu$_2$O$_3$.Comment: 7 pages, 8 postscript figures, revtex, addition of figure 8 and a section with experimental predictions, submmited to Phys. Rev. B in May 199

Transitions from small to large Fermi momenta in a one-dimensional Kondo lattice model

We study a one-dimensional system that consists of an electron gas coupled to a spin-1/2 chain by Kondo interaction away from half-filling. We show that zero-temperature transitions between phases with "small" and "large" Fermi momenta can be continuous. Such a continuous but Fermi-momentum-changing transition arises in the presence of spin anisotropy, from a Luttinger liquid with a small Fermi momentum to a Kondo-dimer phase with a large Fermi momentum. We have also added a frustrating next-nearest-neighbor interaction in the spin chain to show the possibility of a similar Fermi-momentum-changing transition, between the Kondo phase and a spin-Peierls phase, in the spin isotropic case. This transition, however, appears to involve a region in which the two phases coexist.Comment: The updated version clarifies the definitions of small and large Fermi momenta, the role of anisotropy, and how Kondo interaction affects Luttinger liquid phase. 12 pages, 5 figure

Prediction of sustained remission of chronic hepatitis C after a 12-month course of alfa interferon

alpha-Interferon therapy normalizes aminotransferase levels in approximately 50% of the patients with chronic hepatitis C, but post-therapy relapses are common and predictive factors of sustained response remain largely unknown. We retrospectively assessed several parameters as predictors of sustained remission after a 12-month course of lymphoblastoid alpha-interferon: the Knodell histological activity index, serum levels of procollagen type III peptide, serum HCV-RNA, anti-alpha-interferon antibodies, and anti-HCV antibodies (C-100-3), all at month 12. Thirty-seven patients were studied. Fourteen patients were non-responders (38%), 15 patients experienced a sustained response (40.5%) and eight patients responded similarly but relapsed after alpha-interferon withdrawal (21.5%). A decrease in the histological activity index above 5, normalization of procollagen type III peptide levels (< 12 ng/ml) and the absence of viremia after treatment were all significantly associated with a sustained response (p = 0.008, p = 0.007 and p = 0.037, respectively). Anti-interferon antibodies were detected in only one non-responder patient. Anti-C-100-3 antibodies became undetectable at month 12 in 5 of the 15 sustained responders. The best prediction of sustained response was obtained from the three variables independent of multivariate analysis according to the following equation: F = 0.872 + 0.067 x K (decrease of histological index) -0.052 x P (procollagen type III peptide levels at month 12) -0.28 x R (HCV-RNA at month 12; R = 2 when present and R = 1 when absent). A score higher than 0 predicted sustained remission with a 100% sensitivity and specificity in this series of patients