Synthesis and functionalization of casein nanoparticles with aptamers for triple-negative breast cancer targeting

This work shows the synthesis of a drug delivery system made of casein nanoparticles able to host hydrophobic molecules and be functionalized with aptamers targeting the epidermal growth factor receptor. In vitro cell viability and uptake analyses, performed on triple-negative breast cancer cells, confirmed the safety profile and the target selectivity

PO-038 PDGFRβ as a new biomarker for metastatic triple-negative breast cancer: development of a theranostic anti-PDGFRβ aptamer for imaging and suppression of metastases

Introduction Triple-negative breast cancers (TNBCs) are a heterogeneous group of aggressive tumours lacking oestrogen and progesterone receptors and HER2 receptor, thus excluding the possibility of using targeted therapy against these proteins. Mesenchymal-like (ML) subtype, characterised by a stem-like, undifferentiated phenotype, is more invasive and metastatic than other TNBC subtypes and has a strong tendency to form vasculogenic mimicry (VM). Recently, platelet derived growth factor receptor β (PDGFRβ) has been shown to play a role in VM of TNBC. Regrettably, therapies targeting PDGFRβ with tyrosine kinase inhibitors are not effective in treating TNBCs, thus developing new strategies to target PDGFRβ in TNBC patients is crucial to improve their chances of survival. Here, we describe the characterisation of the Gint4.T anti-PDGFRβ nuclease-resistant RNA aptamer as high efficacious theranostic tool for imaging and suppression of ML TNBC metastases. Material and methods Immunohistochemical analyses on a human TNBC tissue microarray was performed to correlate PDGFRβ expression with clinical and molecular features of different subtypes. Functional assays were conducted on PDGFRβ-positive ML BT-549 and MDA-MB-231 cells to investigate the effect of Gint4.T in interfering with cell growth in 3D conditions, migration, invasion and VM formation. Gint4.T was conjugated with near-infrared (NIR) fluorescent VivoTag-S680 and its binding specificity to receptor was confirmed both in vitro (confocal microscopy and flow cytometry analyses of TNBC cells) and in vivo (fluorescence molecular tomography in mice bearing TNBC xenografts). MDA-MB-231 cells were i.v. injected in nude mice and Gint4.T-NIR was used to detect lung metastases in mice untreated or i.v. injected with Gint4.T or a scrambled aptamer. Results and discussions The expression of PDGFRβ was observed in human TNBC samples characterised by higher metastatic behaviour. Treatment of TNBC cell lines with Gint4.T aptamer blocked their invasive growth and vasculogenic properties in 3D culture conditions, and strongly reduced cell migration/invasion in vitro and metastases formation in vivo. The Gint4.T-NIR was able to specifically bind to TNBC xenografts and detect lung metastases in vivo. Therefore, the aptamer revealed a high efficacious theranostic tool for imaging and suppression of TNBC metastases. Conclusion These studies indicate PDGFRβ as a new biomarker for ML and metastatic TNBC subtype and propose a novel targeting agent for the diagnosis and treatment of metastatic TNBCs

Inhibition of Bone Marrow-Derived Mesenchymal Stem Cells Homing Towards Triple-Negative Breast Cancer Microenvironment Using an Anti-PDGFRβ Aptamer

Bone marrow-derived mesenchymal stem cells (BM-MSCs) are shown to participate in tumor progression by establishing a favorable tumor microenvironment (TME) that promote metastasis through a cytokine networks. However, the mechanism of homing and recruitment of BM-MSCs into tumors and their potential role in malignant tissue progression is poorly understood and controversial. Here we show that BM-MSCs increase aggressiveness of triple-negative breast cancer (TNBC) cell lines evaluated as capability to migrate, invade and acquire stemness markers. Importantly, we demonstrate that the treatment of BM-MSCs with a nuclease-resistant RNA aptamer against platelet-derived growth factor receptor β (PDGFRβ) causes the inhibition of receptor-dependent signaling pathways thus drastically hampering BM-MSC recruitment towards TNBC cell lines and BM-MSCs trans-differentiation into carcinoma-associated fibroblast (CAF)-like cells. Moreover, in vivo molecular imaging analysis demonstrated the aptamer ability to prevent BM-MSCs homing to TNBC xenografts. Collectively, our results indicate the anti-PDGFRβ aptamer as a novel therapeutic tool to interfere with BM-MSCs attraction to TNBC providing the rationale to further explore the aptamer in more complex pre-clinical settings

SNOM Imaging of Photoinduced Microstructures in Azo-Polyacrylates

Polymer liquid crystals with a photosensitive azobenzene side chain (azo-scPLC) are interesting materials because of their potential in optical switching and high density optical data storage applications. By illumination with blue linearly polarized light, the azobenzene chromophores undergo repeated trans-cis-trans isomerization cycles, resulting in reorientation of the side chains perpendicular to the electric field direction. We investigate the structural effects due to molecular reorientation in azo-scPLC on the scale of 10-100 nm by using a scanning near-field optical microscope (SNOM). We have selected a SNOM contrast mechanism suitable for domain discrimination by modulating the polarization at the input of the SNOM fiber probe and measuring the sample response with a lock-in technique, since the SNOM optical signal is polarization dependent. We image topographic and optical spontaneous structures of a Langmuir-Schaeffer multilayer of azo-scPLC and photoinduced micron-size patterns previously created by far-field laser illumination. We also present preliminary results in nanowriting, obtained by a pump and probe technique performed through the SNOM probe

Kinematic comparison among players of different level in tennis serve

The tennis serve was studied by many authors (Elliott 1995; Reid 2008). Although, in this previous works, kinetics and kinematics aspects were studied, but they did not analysed the differences of the body displacement as regards the racket and the body angles at the instant of impact, among players of different level. The aim of this study is to compare the ball, racket and body kinematics, in order to find the technical differences among Experts, Intermediates and Beginners players. Methods 18 right-handed subjects performed 16 serves each one, during a training session. The players were divided in 3 groups (based on the national ranking), 8 Experts 5 Intermediates, 5 Beginners. Three 50Hz cameras were located outside the court, with 120\ub0 between the optical axis angles. The serve area was calibrated with a 3D object with known dimensions (1,10 x 1,10 x 2 m.), using 16 points. Simi Motion Analysis System was used for a manual digitalization to obtain 3D coordinate data. 25 points were digitized from the same operator (19 for the body, 5 for the racket and 1 for the ball). Excel, Matlab and Spss softwares were used to analysed the data. The determination of the instant of impact was made by Camorani et al. (2007,P. 173). The variables were compared among the 3 groups of players using the Kruskal Wallis Test (p<0,05). Results Significant differences were found in ball velocities after impact, in all its directions among all groups, except for the lateral velocity between Intermediates and Beginners players. Regarding the racket differences in linear velocity were found only in the net direction among all groups. The racket angular velocity at impact were significant differences between Experts and Beginners and between Intermediates and Beginners players. The height of the ball impact was statistically different among all groups. The ball throw test (200g), used as explosive strength index, gave the same results of the racket angular velocity. Only 4 variables on 16 analyzed showed statistically significant differences among the groups. In particular, the wrist position (dominant arm) respect the racket centre on the sagittal plane at impact, resulted significant different between Experts and Beginners and between Intermediates and Beginners players. The lateral trunk flexion at impact did not show significant differences only between the Experts and Beginners groups. The left knee flexion (anterior knee) resulted significant only when the racket arrive at its lowest point during the cocking phase (RLP), and this significant difference was between Experts and Beginners. The racket longitudinal angle resulted significant only between Experts and Beginners. The sequent variables were not statistically different: the position of the shoulders respect the racket on the frontal and saggital plane, the position of the wrist respect the racket on the frontal plane, the shoulders angles between the frontal and saggital plane, the elbow angle, the wrist angle, the trunk angle between the frontal plane, the trunk torsion angle, the maximum knee flexion angle, the knee angle at impact, the racket trasverse angle. Discussion As expected the performance indexes are significant different among the groups. The anthropometric data and the height of impact of the ball, the muscular strength (ball throw test) can give an important explanation for significant differences showed by the ball and racket velocities. As appears from this study, the 3 groups use different techniques strategies during the cocking phase and at the instant of impact. During the cocking phase the maximum knee flexion is similar among the groups, but at RLP the knee angle shows a significant difference between Experts and Beginners. The up word force is more utilized from the Experts (confirmed by knee angle at impact). The Beginners cannot use the leg cocking, for the up force, in the right time section. Comparing the lateral trunk flexion, th..

Reliability and validity of coordination test battery for scholl age

To date many studies investigated the coordination abilities in school age, but there is a lack information about the validity and reliability of coordination test in the Italian scholar population. The aim of this research was to establish the reliability and the validity of a battery of motor tests used in school age. 295 children (160 male, 135 female) aged between 7 and 11 were tested with 10 motor tests to assess: balance, speed, eye-hand coordination, muscular explosive stength of lower and upper limbs (at 100% and 75% of maximum effort), laterality, kinaestetic differentiation, frequency and precision of movements. Anthropometric data of height and weight were determined in 174 subjects. To value the reliability and the validity were used the statistical correlation cluster analysis and factorial analysis. The reliability was studied through the Test-Retest method calculating the correlation index (R) between the trials of the same test. R was over the 0,80 for all test, except of balance (0,78) and the basketball throw with 75% of the maximum effort (0,76) but this results were still sufficient. Best reliabilities resulted from the sprint (0,93) and the standing broad jump (0,92). Results showed a good correlation between conditional tests, that tended to make homogeneous groups based on cluster an factorial analysis. Coordination tests seemed more independent. Balance and kinaesthetic differentiation test were combined with the other tests resulting in inferior levels of correlation. The conditional and coordination factorial structure results stable dividing the subjects in class age of a year. The used tests are good indicators of the conditional and coordination abilities for all age tested

Mappatura di precisione delle aree di pertinenza del fiume Arno nella Provincia di Firenze

Mappatura Di Precisione Delle Aree Di Pertinenza Del Fiume Arno Nella Provincia Di Firenz

Optical bit stability and relaxation processes in a liquid crystal polymer with a photosensitive azo dye molecule as side group

We present a study of optically-induced molecular relaxation and optical writing processes in a photosensitive liquid crystalline polymer, containing the azobenzene moiety in the side chain. Linear and non linear ESR spectroscopies, thermal analysis and rheology investigations carried on azo polymethacrylate (PMA) samples subjected to different thermal treatments have allowed to single out a suitable procedure to get stable, homogeneous substrates. Optical studies on micrometer length scale, adopting the selected procedure, have confirmed the stability conditions in both unaligned and aligned samples. The temperature dependence of the bit stability has been determined. The writing threshold power and writing rate have been measured. The results are discussed within the perspective of extension to the nanometer length scale