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2.
J Oncol ; 2019: 5879616, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31827511

RESUMO

The recent introduction of the "precision medicine" concept in oncology pushed cancer research to focus on dynamic measurable biomarkers able to predict responses to novel anticancer therapies in order to improve clinical outcomes. Recently, the involvement of extracellular vesicles (EVs) in cancer pathophysiology has been described, and given their release from all cell types under specific stimuli, EVs have also been proposed as potential biomarkers in cancer. Among the techniques used to study EVs, flow cytometry has a high clinical potential. Here, we have applied a recently developed and simplified flow cytometry method for circulating EV enumeration, subtyping, and isolation from a large cohort of metastatic and locally advanced nonhaematological cancer patients (N = 106); samples from gender- and age-matched healthy volunteers were also analysed. A large spectrum of cancer-related markers was used to analyse differences in terms of peripheral blood circulating EV phenotypes between patients and healthy volunteers, as well as their correlation to clinical outcomes. Finally, EVs from patients and controls were isolated by fluorescence-activated cell sorting, and their protein cargoes were analysed by proteomics. Results demonstrated that EV counts were significantly higher in cancer patients than in healthy volunteers, as previously reported. More interestingly, results also demonstrated that cancer patients presented higher concentrations of circulating CD31+ endothelial-derived and tumour cancer stem cell-derived CD133 + CD326- EVs, when compared to healthy volunteers. Furthermore, higher levels of CD133 + CD326- EVs showed a significant correlation with a poor overall survival. Additionally, proteomics analysis of EV cargoes demonstrated disparities in terms of protein content and function between circulating EVs in cancer patients and healthy controls. Overall, our data strongly suggest that blood circulating cancer stem cell-derived EVs may have a role as a diagnostic and prognostic biomarker in cancer.

3.
Stem Cell Rev Rep ; 10(3): 429-46, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24619862

RESUMO

Cryopreservation is the only method for long-term storage of viable cells and tissues used for cellular therapy, stem cell transplantation and/or tissue engineering. However, the freeze-thaw process strongly contributes to cell and tissue damage through several mechanisms, including oxidative stress, cell injury from intracellular ice formation and altered physical cellular properties. Our previous proteomics investigation was carried out on Wharton's Jelly Stem Cells (WJSCs) having similar properties to adult mesenchymal stem cells and thus representing a rich source of primitive cells to be potentially used in regenerative medicine. The aim of the present work was to investigate molecular changes that occur in WJSCs proteome in different experimental conditions: fresh primary cell culture and frozen cell. To analyze changes in protein expression of WJSCs undergoing different culturing procedures, we performed a comparative proteomic analysis (2DE followed by MALDI-TOF MS/MS nanoESI-Q-TOF MS coupled with nanoLC) between WJSCs from fresh and frozen cell culturing, respectively. Frozen WJSCs showed qualitative and quantitative changes compared to cells from fresh preparation, expressing proteins involved in replication, cellular defence mechanism and metabolism, that could ensure freeze-thaw survival. The results of this study could play a key role in elucidating possible mechanisms related to maintaining active proliferation and maximal cellular plasticity and thus making the use of WJSCs in cell therapy safe following bio-banking.


Assuntos
Criopreservação , Células-Tronco Mesenquimais , Proteoma/metabolismo , Adipogenia , Antígenos CD/metabolismo , Separação Celular , Células Cultivadas , Humanos , Osteogênese , Mapas de Interação de Proteínas , Telômero/genética , Cordão Umbilical/citologia
4.
Artif Intell Med ; 28(2): 141-63, 2003 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12893117

RESUMO

The inherent black-box nature of neural networks is an important drawback with respect to the problem of explanation of neural network responses. Although several articles have tackled the problem of rule extraction from a single neural network, just a few papers have investigated rule extraction from several combined neural networks. In this article we describe how to translate symbolic rules into the Discretized Interpretable Multi-Layer Perceptron (DIMLP) and how to extract rules from one or several combined neural networks. Our approach consists of characterizing discriminant hyperplane frontiers. Unordered rules are extracted in polynomial time with respect to the size of the problem and the size of the network. Moreover, the degree of matching between extracted rules and neural network responses is 100% on training examples. We applied single DIMLP networks to 17 data sets related to medical diagnosis and medical prognosis problems. Results based on 10-fold cross-validation showed that the DIMLP model was on average as accurate as standard multi-layer perceptrons (MLP). Furthermore, DIMLP networks were significantly more accurate than CN2 on eight problems, whereas only on one problem CN2 was better than DIMLP. Finally, a non-Hodgkin lymphoma diagnosis problem based on classification of electrophoresis gels was defined. It turned out that ensembles of DIMLP networks were significantly more accurate than CN2 (96.1% +/- 1.4 versus 82.7% +/- 4.0). Finally, symbolic rules revealed the presence of five important spots for the discrimination of the class of Lymphocyte Leukemia/Chronic Lymphoid Leukemia (Lc/LLc), and the class of Centrocytic Lymphoma (Cc).


Assuntos
Modelos Teóricos , Redes Neurais de Computação , Algoritmos , Árvores de Decisões , Diagnóstico Diferencial , Eletroforese em Gel Bidimensional , Humanos , Leucemia Linfoide/diagnóstico , Linfoma de Célula do Manto/diagnóstico , Reprodutibilidade dos Testes , Software
5.
Ann Ital Chir ; 70(2): 259-62; discussion 262-3, 1999.
Artigo em Italiano | MEDLINE | ID: mdl-10434460

RESUMO

Multiple symmetric lipomatosis (MSL) is a rare condition of the fatty tissue affecting mostly white men between 20 and 65 years old especially in the mediterranean region. The disease is characterized by a massive development of large unencapsulated lipomas mainly located on the subcutaneous tissue of the cervical, deltoid, thoracic, abdominal and lumbar areas and it is often accompanied by hyperuricemia, dyslipemia, macrocytic anaemia, peripheral neuropathy, impaired glucose tolerance and alcohol consumption. Alcohol could both promote the development of lipomas through changes in the number and function of beta-adrenergic receptors and because of its lipogenic and antilipolytic action. Other authors have hypothesized that the defective lipolysis is due to a disorder in the mitochondria of brown fat whose distribution is similar to the peculiar position of the lipomas in the MSL. In this report the authors describe an atypical clinical picture of MSL in a 65-years-old white man.


Assuntos
Lipomatose Simétrica Múltipla/diagnóstico , Idoso , Doença Crônica , Diagnóstico Diferencial , Humanos , Lipomatose Simétrica Múltipla/etiologia , Masculino
6.
Immunology ; 88(4): 501-7, 1996 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-8881749

RESUMO

Ageing is associated with complex remodelling in the phenotypic and functional profiles of T lymphocytes. We investigated whether expression of CD28 antigen on T cells is conserved throughout adulthood and ageing in humans. For this purpose we analysed T cells obtained from peripheral blood of 102 healthy people of ages ranging from 20 to 105 years. We found an age-related increase of CD28- T cells in percentage and absolute number, predominantly among CD8+ T cells. CD28- T cells from aged donors analysed by flow cytometry appeared as resting cells (not expressing CD25, CD38, CD69, CD71, DR), bearing markers of cytotoxic activity (CD 11b and CD 57) and with a phenotype compatible with 'memory' cells (up-regulated CD2 and CD11a; CD62L absent). At the functional level, freshly isolated purified CD28- CD8+ T cells showed high anti-CD3 redirected cytotoxic activity against Fc-bearing P815 cells. The same activity tested on freshly isolated bulk T lymphocytes was significantly augmented with age. We found a positive correlation between age, number of CD8+ CD28- T cells and anti-CD3 redirected cytotoxicity by freshly isolated T cells. These data suggest that an activation of unknown nature within the cytotoxic arm of the immune system occurs with age. We speculate that these cytotoxic T lymphocytes (CTL) in vivo may constitute armed effector cells for immediate killing of targets bearing peptides from pathogens of intracellular origin.


Assuntos
Envelhecimento/imunologia , Antígenos CD28/sangue , Linfócitos T CD8-Positivos/imunologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Complexo CD3/sangue , Separação Celular , Citotoxicidade Imunológica , Citometria de Fluxo , Humanos , Contagem de Linfócitos , Pessoa de Meia-Idade
7.
Cell Immunol ; 128(1): 118-29, 1990 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-1971527

RESUMO

We examined morphometric as well as functional characteristics of CD16-positive human peripheral blood lymphocytes on the basis of the coexpression of the CD2 antigen. For morphometric analyses, nuclear area and cellular area were determined by counting line cross-points of a superimposed quadratic lattice test system overlying nuclei and the whole cell, respectively. Moreover, to evaluate the cellular villousity degree, the maximum inscrible circle and an irregular polygon were inscribed within cell profiles. The cytoplasm fraction included between the plasmalemma and the traced irregular polygon was considered as the villous portion of the cell. Finally, the NK capability was measured in a 6-hr 51Cr-release assay with human K-562 myeloid cells as targets. Within the CD16-positive cell population, the CD16-positive/CD2-negative cells seem to represent the most efficient NK cell subset. To the higher NK capability correspond a higher villousity degree and a lower nuclear area/cellular area ratio of the CD2-negative/CD16-positive subset, when compared with CD2-positive/CD16-positive cells.


Assuntos
Antígenos CD/análise , Antígenos de Diferenciação de Linfócitos T/análise , Antígenos de Diferenciação/análise , Células Matadoras Naturais/citologia , Receptores Fc/análise , Receptores Imunológicos/análise , Anticorpos Monoclonais , Antígenos CD2 , Núcleo Celular/ultraestrutura , Separação Celular , Citoplasma/ultraestrutura , Citotoxicidade Imunológica , Humanos , Imunidade Celular , Imunidade Inata , Imuno-Histoquímica , Células Matadoras Naturais/imunologia , Células Matadoras Naturais/ultraestrutura , Receptores de IgG
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