Surface Physicochemical and Structural Analysis of Functionalized Titanium Dioxide Films

Titanium and its alloys are recognized as acceptable materials for many applications. The properties of titanium dioxide (TiO2) thin films are directly related to the structural characteristics of the material, which can be modified with tailor-made functional groups. Reactive bifunctional groups can be bound with hydroxyl-terminated TiO2, leading to the formation of self-assembled monolayers or multilayer films. The understanding of such interactions is necessary to design functional oxide coatings for a large variety of applications. In this study, nanosized TiO2 films were synthesized by the sol-gel method and deposited by spin coating technique upon titanium substrate. Subsequently, TiO2 thin films were functionalized with (3-aminopropyl)trimethoxysilane (APTMS), 3-(4-aminophenyl)propionic acid (APPA), 3-mercaptopropionic acid (MPA) or polyethylene glycol (PEG). Surface characterization by XPS, surface roughness, and contact angle indicated successful functionalization and allowed for identification of the preferential conformation of each molecule. APPA and APTMS presented free amine groups indicating the attachment to the surface by carboxyl and silane groups, respectively. Mercapto coupling from MPA showed the formation of S-Ti bonds. PEG-coated surface revealed polymerization of several hydroxyl groups that crosslinked with each other. Analyzing the mode of attachment at the interface of the metal oxide and functional group may help in the development of improved functional materials

Characterization and prognostic relevance of circulating microvesicles in chronic lymphocytic leukemia

Microvescicles (MV) are shedding particles released by normal and neoplastic cells, whose levels in biological fluids highlight their potential role as disease biomarkers and therapeutic targets. By analyzing 131 newly diagnosed chronic lymphocytic leukemia (CLL), we found that the absolute number of serum CLL MV was significantly higher than in controls, in particular in advanced stages of disease. In addition, CD19\u2009+\u2009and CD37+, B-cell derived MV, significantly correlated with high tumor burden. Absolute MV number cutoff selected by ROC analysis distinguished Rai stage 0 patients with shorter time to treatment (TTT) from those with more stable disease. Likewise, in the entire cohort, two groups of patients with different overall survival (OS) and different TTT were identified. At multivariate analysis, serum MV independently predicted for OS (along with Rai stage) and TTT (along with Rai stage, lymphocytes and CD38). In conclusion, circulating MV represent a new potential prognostic biomarker in CLL

MicroRNA-155 in serum-derived extracellular vesicles as a potential biomarker for hematologic malignancies - a short report

The use of extracellular vesicles (EVs) from body fluids as "liquid biopsies" is emerging as a promising approach for the diagnosis, prognosis and therapeutic monitoring of cancer patients. MicroRNA-155 (miR155), a non-coding transcript of the B-cell integration cluster (BIC) gene, has been reported to play a critical role in the pathogenesis of several types of hematologic malignancies (HMs) in which high miR155 levels have been found. At yet, however, the EV miR155 level and its putative clinical relevance in sera of HM patients have not been reported. METHODS: EVs from sera of representative patients with eight different HMs and healthy subjects (controls) were isolated using differential centrifugation. The identity and quality of the EVs were verified by atomic force and transmission electron microscopy. The EV miR155 levels were measured by quantitative RT-PCR. The sensitivity, specificity and area under the curve (AUC) of differences in EV miR155 levels were determined using ROC curve analyses. RESULTS: We found that the EV miR155 levels were significantly higher in chronic lymphocytic leukemia (CLL), acute myeloid leukemia (AML) and Waldenstr\uf6m's macroglobulinemia (WM) cases compared to controls. Conversely, we found that the EV miR155 levels were significantly lower in myelodysplastic syndrome (MDS) and multiple myeloma (MM) cases. No differences were found in follicular lymphoma (FL), diffuse large B-cell lymphoma (DLBCL) or Hodgkin's Lymphoma (HL) cases compared to controls. EV miR155 ROC curve analyses revealed significantly different patterns in CLL and AML cases compared to controls, and in AML cases compared to MDS cases (p = 0.004, p = 0.01 and p = 0.04, respectively). In addition, we found that high EV miR155 levels correlated with high white blood cell counts in AML patients. CONCLUSION: Our data indicate that EV miR155 may serve as an attractive new, non-invasive diagnostic biomarker in human hematologic malignancies