16 research outputs found
Comparison of [18F] fluorocholine PET/CT with [99mTc] sestamibi and ultrasonography to detect parathyroid lesions in primary hyperparathyroidism: a prospective study.
Background: Primary hyperparathyroidism is a common endocrine disorder produced by the increase of parathyroid hormone (PTH) due to a benign adenoma of a single parathyroid gland, or as multiple gland hyperplasia, or as a rare malignant tumor. Preoperative imaging scans are frequently necessary for the minimally invasive parathyroidectomies to identify the location of enlarged parathyroid glands and to design the procedure. Methods: The diagnostic reliability of [18F]fluorocholine positron emission tomography/computed tomography (FCH PET/CT), [99mTc]sestamibi [multiplexed ion beam imaging (MIBI)] and cervical ultrasonography was analyzed in 37 patients diagnosed with primary hyperparathyroidism undergoing minimally invasive parathyroidectomy. The three preoperative imaging techniques were correlated with intraoperative and histopathological findings as well as changes in biochemical parameters (serum PTH and calcium levels). Statistical analysis was carried out with SPSS version 24.0. Results: In 30 of 37 patients (81.1%), FCH PET/CT correctly localized the pathological gland. In 3 cases of ectopic adenomas, the accuracy of the techniques was 100% (3/3) for FCH PET/CT, 66.7% (2/3) for MIBI, and 33.3% (1/3) for neck ultrasonography. Neither neck ultrasonography nor MIBI were able to locate pathological parathyroid glands in those patients with multiglandular disease, while FCH PET/CT correctly located one patient (1/3, 33.3%) with two adenomas and 3 patients (3/6, 50.0%) with hyperplasia. The three imaging techniques, FCH PET/CT, MIBI and neck ultrasound yielded a sensitivity of 92.1%, 57.9% and 32.4%, a positive predictive value of 94.6%, 84.6% and 78.6%, and a diagnostic accuracy of 96.4%, 85.7% and 79.0%, respectively. Conclusions: In this group of patients diagnosed with primary hyperparathyroidism, FCH PET/CT was superior to MIBI and neck ultrasound in detecting adenomas, particularly in the presence of ectopic glands or multiglandular disease
Prognostic value of hematogenous dissemination and biological profile of the tumor in early breast cancer patients: A prospective observational study
<p>Abstract</p> <p>Background</p> <p>The aim of this study was to investigate the incidence and prognostic value of disseminated tumor cells in bone marrow of breast carcinoma patients with early disease, and to analyze this finding in relation to lymph node involvement, determined by sentinel lymph node (SLN) biopsy analysis, and to prognostic factors of interest.</p> <p>Methods</p> <p>104 patients with operable (T < 3 cm) breast cancer and clinically- and sonographically-negative axillary lymph nodes were scheduled for SLN biopsy. Bone marrow aspirates were collected before the start of surgery from both iliac crests, and mononuclear cell layers were separated by density centrifugation (Lymphoprep). Slide preparations were then examined for the presence of disseminated tumor cells by immunocytochemistry with anti-cytokeratin antibodies (A45-B/B3). Lymphoscintigraphy was performed 2 hours after intratumor administration of 2 mCi (74 MBq) of 99mTc colloidal albumin. The SLN was evaluated for the presence of tumor cells by hematoxylin-eosin staining and, when negative, by immunocytochemistry using anti-cytokeratin antibody (CAM 5.2). Survival analyses and comparative analyses were performed on the results of bone marrow determinations, SLN biopsy, and known prognostic factors, including breast cancer subtypes according to the simplified classification based on ER, PR and HER2.</p> <p>Results</p> <p>Lymph node and hematogenous dissemination occur in one-third of patients with early-stage breast cancer, although not necessarily simultaneously. In our study, disseminated tumor cells were identified in 22% of bone marrow aspirates, whereas 28% of patients had axillary lymph node involvement. Simultaneous lymph node and bone marrow involvement was found in only 5 patients (nonsignificant). In the survival study (60 months), a higher, although nonsignificant rate of disease-related events (13%) was seen in patients with disseminated tumor cells in bone marrow, and a significant association of events was documented with the known, more aggressive tumor subtypes: triple negative receptor status (21%) and positive ERBB2 status (29%).</p> <p>Conclusions</p> <p>Tumor cell detection in bone marrow can be considered a valid prognostic parameter in patients with early disease. However, the classic prognostic factors remain highly relevant, and the newer breast cancer subtypes are also useful for this purpose.</p
The reactions of SO3 with HO2 radical and H2O...HO2 radical complex. Theoretical study on the atmospheric formation of HSO5 and H2SO4
10 pages, 6 figures, 2 tables.-- PMID: 20165760 [PubMed].-- Available online Jan 14, 2010.-- Supporting information available at: http://dx.doi.org/10.1039/b916659aThe influence of a single water molecule on the gas-phase reactivity of the HO2 radical has been investigated by studying the reactions of SO3 with the HO2 radical and with the H2OHO2 radical complex. The naked reaction leads to the formation of the HSO5 radical, with a computed binding energy of 13.81 kcal mol−1. The reaction with the H2OHO2 radical complex can give two different products, namely (a) HSO5 + H2O, which has a binding energy that is computed to be 4.76 kcal mol−1 more stable than the SO3 + H2OHO2 reactants ((E + ZPE) at 0K) and an estimated branching ratio of about 34% at 298K and (b) sulfuric acid and the hydroperoxyl radical, which is computed to be 10.51 kcal mol−1 below the energy of the reactants ((E + ZPE) at 0K), with an estimated branching ratio of about 66% at 298K. The fact that one of the products is H2SO4 may have relevance in the chemistry of the atmosphere. Interestingly, the water molecule acts as a catalyst, [as it occurs in (a)] or as a reactant [as it occurs in (b)]. For a sake of completeness we have also calculated the anharmonic vibrational frequencies for HO2, HSO5, the HSO5H2O hydrogen bonded complex, H2SO4, and two H2SO4H2O complexes, in order to help with the possible experimental identification of some of these species.This research has been supported by the Spanish Dirección General de Investigación Científica y Técnica (DGYCIT, grant CTQ2008-06536/BQU) and by the Generalitat de Catalunya (Grant 2009SGR01472).Peer reviewe
Role of vibrational anharmonicity in atmospheric radical hydrogen-bonded complexes
12 pages, 2 figures, 8 tables.-- PMID: 19809669 [PubMed].-- Available online Jun 19, 2009.Harmonic and anharmonic vibrational frequency calculations are reported for the most stable hydrogen bonded complexes formed between the hydroperoxyl radical and formic, acetic, nitric, and sulfuric acids which are of atmospheric interest. A comparison between the calculated IR spectra of the hydrogen bonded complexes with the corresponding separate monomers is also reported with the aim to facilitate a possible experimental identification of these complexes. The calculations have been carried out using the second-order vibrational perturbative treatment implemented by Barone applied to the PES obtained with the B3LYP functional using the 6-31+G(d,p) and 6-311+G(2d,2p) basis sets. Our calculations for the separate monomers predict vibrational frequencies with quite a good agreement with the experimental values. The anharmonic contribution results in differences of around 40 cm-1 with respect to the harmonic values; although in some cases involving highly anharmonic modes, these differences can rise up to 300 and 450 cm-1.M.T. acknowledges the European Community for financial help through postdoctoral grant MEIF-CT-2006-025362. The financial support of the Spanish MEC and the Catalan Departament d’Universitats, Recerca i Societat de la Informació (DURSI), respectively, is acknowledged according to the following programmes: CTQ2008-06696/BQU and 2005SGR- 00238 (J.M.L.); and CTQ2005-07790 and 2005SGR00111 (J.M.A.).Peer reviewe
Theoretical study of the switching between Hückel and Möbius topologies for expanded porphyrins
The expanded porphyrins have become a useful tool to synthesize new Hückel-to-Möbius topological switches. Only applying small changes in the external conditions (temperature, solvent, redox potential) or in the structure of the ring allows the expanded porphyrins to achieve Hückel and Möbius topologies with distinct aromaticities and magnetic and electric properties. In this work, we report a theoretical investigation of the reaction mechanism of the conformational switch between the Hückel planar and the singly twisted Möbius structures for two different meso-substituted [28]hexaphyrins(1.1.1.1.1.1); that is, the meso-substituents are the hydrogen atoms and pentafluorophenyls. Calculations are performed with the B3LYP, BH&HLYP, CAM-B3LYP, M05-2X, and MP2 methodologies along with the 6-31G and 6-311G(d,p) basis sets. For benchmarking purposes, single-point energies are calculated at the CCSD(T)/6-31G level. Our results conclude that, in overall, CAM-B3LYP and M05-2X are the methods that provide the most equilibrated results for the different steps of the topological switch. In addition, we point out that the ring strain and the steric effect of the meso-substituents play a relevant role in the thermochemistry and kinetics of the Hückel-to-Möbius topological switches.This research has been supported by the Research Executive Agency (Grant Agreement no. PERG05-GA-2009-249310) and by the Generalitat de Catalunya (Grant 2009SGR01472). The calculations described in this work were carried out at the Centre de Supercomputació de Catalunya (CESCA). M.T-S. acknowledges the CSIC for the JAE-DOC contract, and E.M. acknowledges a contract under the PERG05-GA-2009-249310 grant. We are grateful to Ramon Crehuet for his help in the NEB calculationsPeer Reviewe
Sulfuric acid as autocatalyst in the formation of sulfuric acid
Sulfuric acid can act as a catalyst of its own formation. We have carried out a computational investigation on the gas-phase formation of H 2SO4 by hydrolysis of SO3 involving one and two water molecules, and also in the presence of sulfuric acid and its complexes with one and two water molecules. The hydrolysis of SO3 requires the concurrence of two water molecules, one of them acting as a catalyzer, and our results predict an important catalytic effect, ranging between 3 and 11 kcal·mol-1 when the catalytic water molecule is substituted by a sulfuric acid molecule or one of its hydrates. In these cases, the reaction products are either bare sulfuric acid dimer or sulfuric acid dimer complexed with a water molecule. There are broad implications from these new findings. The results of the present investigation show that the catalytic effect of sulfuric acid in the SO3 hydrolysis can be important in the Earth's stratosphere, in the heterogeneous formation of sulfuric acid and in the formation of aerosols, in H2SO4 formation by aircraft engines, and also in understanding the formation of sulfuric acid in the atmosphere of Venus. © 2012 American Chemical Society.This work was supported by the Spanish DGYCIT (CTQ2011-27812) and the Generalitat de Catalunya (Grant 2009SGR01472). The calculations described in this work were carried out at the Centre de Supercomputació de Catalunya (CESCA) and at CTI-CSIC. M.T.-S. acknowledges the CSIC for a JAE-Doc contract. We also thank the reviewers for their comments and suggestions regarding this work.Peer Reviewe
Upper Extremity Deep Venous Thrombosis in Cancer Patients with Venous Access Devices - Prophylaxis with a Low Molecular Weight Heparin (Fragmin)
Relevance of the DFT method to study expanded porphyrins with different topologies
Meso‐aryl expanded porphyrins present a structural versatility that allows them to achieve different topologies with distinct aromaticities. Several studies appeared in the literature studying these topological switches from an experimental and theoretical point of view. Most of these publications include density functional theory calculations, being the B3LYP the most used methodology. In this work, we show that the selection of the functional has a critical role on the geometric, energetic, and magnetic results of these expanded porphyrins, and that the use of an inadequate methodology can even generate spurious stationary points on the potential energy surface. To illustrate these aspects, in this article we have studied different molecular distortions of two expanded porphyrins, [32]‐heptaphyrin and [26]‐hexaphyrin using 11 DFT functionals and performing single point energy calculations at the local pair natural orbital coupled cluster DLPNO‐CCSD(T) method, which have been carried out for benchmarking purposes. For some selected functionals, the dispersion effects have also been evaluated using the D3‐Grimme's dispersion correction with Becke–Johnson damping. Our results let us to conclude that the CAM‐B3LYP, M05‐2X, and M06‐2X functionals are the methodologies that provide a more consistent description of these topological switches, while other methods, such as B3LYP, BPE, and BP86, show a biased description.-Ministerio de Economía y Competitividad of Spain . Grant Numbers: CTQ2016‐80375‐P , CTQ2014‐52525‐P , CTQ2014‐51912‐REDC
-Universidad del País Vasco ‐ Euskal Herriko Unibertsitatea (UPV/EHU) . Grant Number: UFI11/22 QOSYC
-Basque Government . Grant Number: IT673‐13
-Generalitat de Catalunya . Grant Number: 2014SGR139Peer reviewe
Necrologia y dos articulos doctrinales: el miedo al peritoneo, la operación de Alexander-Adams
Conté: Necrología del doctor D. Santiago de Rull y Artós leída en sesión extraordinaria de la Academia y Laboratorio de Ciencias Médicas de Cataluña la noche del 22 de Diciembre de 1887 / por Miguel A. Farga