Proteomica e metabolomica nella medicina trasfusionale: nuove tecnologie per il miglioramento della conservazione dei globuli

Despite decades of significant technological improvements, red blood cells can be stored under standard blood bank conditions for a limited span of life because RBC undergo a series of biochemical and physical changes, the so-called “storage lesions” that are related to the promotion of apoptosis-like phenomena. These anomalies compromise red cell survival upon transfusion and in turn transfusion efficacy in the recipient. In the first section, this PhD thesis would evaluate new technologies to improve red cell storage quality, in term of safety and efficacy. To this end it was performed a biochemical and mass spectrometry-based analysis of: (i) high-glycerol frozen RBCs (i.e., stored with a final concentration of 40% glycerol at -80°C for about 10 years); (ii) RBCs stored under standard blood banking with the supplementation of antioxidants (N-acetyl-L-cysteine and ascorbic acid). In the second section, the thesis would describe an innovative method to evaluate red cell storage quality through an extensive investigation of RBC cytosolic multi-protein complexes. In the light of this, it was performed a proteomic analysis in order to identify multimeric protein complexes that play a critical role in the maintenance of red blood cell functionality and survival in vivo. Future investigations should expand the existing knowledge and determine whether and how these complexes might influence red cell ageing in vivo and in vitro, other than the insurgence of specific pathologies.Nonostante gli innumerevoli miglioramenti tecnologici degli ultimi decenni, i globuli rossi possono essere conservati in sacca trasfusionale per un periodo di tempo limitato. Ciò a causa delle cosiddette “storage lesions”, ossia modificazioni di natura biochimica e fisica che sono correlate alla promozione di fenomeni apoptotici. Tali alterazioni cellulari compromettono la sopravvivenza delle cellule trasfuse nel ricevente e, quindi, l’efficacia della trasfusione stessa. Nella prima sezione, questa tesi intende affrontare nuove tecnologie che sono state introdotte per promuovere il miglioramento della conservazione dei concentrati eritrocitari in sacca trasfusionale. Per questo scopo è stata eseguita un’analisi biochimica e basata sulla spettrometria di massa di: (i) high-glycerol frozen RBCs (globuli rossi conservati in 40% di glicerolo a -80°C per circa 10 anni); (ii) globuli rossi conservati secondo gli standard (CPD-SAGM a 4°C) con l’aggiunta di antiossidanti (N-acetil-L-cisteina e acido ascorbico). Nella seconda sezione, la tesi intende descrivere un metodo innovativo e utile per la valutazione della qualità di conservazione dei concentrati eritrocitari. Questo è consentito mediante un’approfondita analisi dei complessi multi-proteici presenti nel citoplasma eritrocitario. Alla luce di ciò, è stata eseguita un’analisi proteomica con lo scopo di indentificare i complessi proteici multimerici che giocano un ruolo cruciale nel mantenimento della funzionalità e della sopravvivenza cellulare in vivo. Indagini future potrebbero determinare se e come tali complessi proteici possano influenzare l’invecchiamento cellulare in vivo e in vitro, oltre che lo sviluppo di determinate patologie.Dottorato di ricerca in Genetica e biologia cellular

Estrogen receptor β and epidermal growth factor receptor as early-stage prognostic biomarkers of non-small cell lung cancer

As 20% of stage I NSCLC patients develop recurrent and often incurable cancer, the identification of prognostic markers has a meaningful clinical application. The biological significance of steroid hormone and EGF receptors, able to regulate key physiological functions, remains elusive in NSCLC. Our aim was to investigate the prognostic input of estrogen receptors (ER·, ERß), progesterone receptors (PR) and EGFR in tumors from 58 stage I NSCLC patients. Antigen expression was analyzed by immunohistochemistry. Prognostic evaluation was performed with the multivariate Cox model. We found that about 70 and 40% of samples expressed ER· or ERß at cytoplasmic or nuclear level, respectively. Besides, only 12.1% of samples weakly expressed nuclear PR and 62.7% showed membrane EGFR staining. Correlation studies indicated an inverse association between EGFR expression and smoking status (p<0.01). Multivariate studies showed that the lack of nuclear ERß or the loss of EGFR expression were independent prognosis markers associated with shorter overall survival. We also found that patients whose tumors were negative for these two biomarkers presented the worst outcome. In conclusion, our findings could be useful for selecting stage I NSCLC patients with poor prognosis to apply an earlier treatment that impacts on survival.Fil: Mauro, Laura Valeria. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Oncología "Ángel H. Roffo"; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Dalurzo, Mercedes. Hospital Italiano; ArgentinaFil: Carlini, María José. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Oncología "Ángel H. Roffo"; ArgentinaFil: Smith, David. Hospital Italiano; ArgentinaFil: Núñez, Myriam Carmen. Hospital Italiano; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Simian, Marina. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Oncología "Ángel H. Roffo"; ArgentinaFil: Lastiri, José. Hospital Italiano; ArgentinaFil: Vasallo, Bartolomé. Hospital Italiano; ArgentinaFil: Bal, Elisa Dora. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Oncología "Ángel H. Roffo"; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Pallotta, María Guadalupe. Hospital Italiano; ArgentinaFil: Puricelli, Lydia Ines. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Oncología "Ángel H. Roffo"; Argentin

Prognostic value of E-cadherin, beta-catenin, MMPs (7 and 9), and TIMPs (1 and 2) in patients with colorectal carcinoma

BACKGROUND AND OBJECTIVES: Therapy of colorectal tumors (CRC) based on histology and clinical factors is insufficient to predict the evolution of each patient. The finding of molecular abnormalities able to differentiate subgroups of patients with bad prognosis will improve our ability to treat them successfully. Our purpose was to analyze retrospectively the prognostic input of E-cadherin, beta-catenin, metalloproteinases (MMPs) (7 and 9), and tissue inhibitors of metalloproteinases (TIMPs) (1 and 2) in patients with a follow-up period of 5 years. METHODS: Antigen expression was analyzed by immunohistochemistry. Prognostic evaluation was performed with the multivariate proportional hazards model. RESULTS: We demonstrated a concomitant loss of E-cadherin and beta-catenin at membranous level and an abnormal accumulation of nuclear beta-catenin. Besides, we found that all MMPs and TIMPs studied were overexpressed in CRC tissue. There was no association between the expression of any of these molecules and the known clinical-pathological parameters employed in CRC pathology. A multivariate analysis demonstrated that the overall survival could be independently predicted by the loss of E-cadherin and the overexpression of TIMP-2. CONCLUSIONS: The expression of E-cadherin and TIMP-2 could be relevant in determining the prognosis of CRC patients and providing a more accurate mechanism for their classification. (c) 2006 Wiley-Liss, Inc.Fil: Bravo Roca, María Fernanda. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Oncología "Ángel H. Roffo"; ArgentinaFil: Mauro, Laura Valeria. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Oncología "Ángel H. Roffo"; ArgentinaFil: Morandi, Ana. Hospital Italiano; ArgentinaFil: Bonadeo, Fernando. Hospital Italiano; ArgentinaFil: Vaccaro, Carlos Alberto. Hospital Italiano; ArgentinaFil: Quintana, Guillermo Ojea. Hospital Italiano; ArgentinaFil: Specterman, Sergio. Hospital Italiano; ArgentinaFil: Bal, Elisa Dora. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Ministerio de Ciencia. Tecnología e Innovación Productiva. Agencia Nacional de Promoción Científica y Tecnológica; ArgentinaFil: Pallotta, María Guadalupe. Hospital Italiano; ArgentinaFil: Puricelli, Lydia Ines. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Oncología; ArgentinaFil: Lastiri, José. Hospital Italiano; Argentin

Monte Carlo evaluation of the Filtered Back Projection method for image reconstruction in proton computed tomography

In this paper the use of the Filtered Back Projection (FBP) Algorithm, in order to reconstruct tomographic images using the high energy (200–250 MeV) proton beams, is investigated. The algorithm has been studied in detail with a Monte Carlo approach and image quality has been analysed and compared with the total absorbed dose. A proton Computed Tomography (pCT) apparatus, developed by our group, has been fully simulated to exploit the power of the Geant4 Monte Carlo toolkit. From the simulation of the apparatus, a set of tomographic images of a test phantom has been reconstructed using the FBP at different absorbed dose values. The images have been evaluated in terms of homogeneity, noise, contrast, spatial and density resolution

Empty vector (false positive).

<p>Empty vector (false positive).</p

p70 fragment interactors.

<p>p70 fragment interactors.</p