“Three-bullets” loaded mesoporous silica nanoparticles for combined photo/chemotherapy

This contribution reports the design, preparation, photophysical and photochemical characterization, as well as a preliminary biological evaluation of mesoporous silica nanoparticles (MSNs) covalently integrating a nitric oxide (NO) photodonor (NOPD) and a singlet oxygen (1O2) photosensitizer (PS) and encapsulating the anticancer doxorubicin (DOX) in a noncovalent fashion. These MSNs bind the NOPD mainly in their inner part and the PS in their outer part in order to judiciously exploit the different diffusion radius of the cytotoxic NO and 1O2. Furthermore this silica nanoconstruct has been devised in such a way to permit the selective excitation of the NOPD and the PS with light sources of different energy in the visible window. We demonstrate that the individual photochemical performances of the photoactive components of the MSNs are not mutually affected, and remain unaltered even in the presence of DOX. As a result, the complete nanoconstruct is able to deliver NO and 1O2 under blue and green light, respectively, and to release DOX under physiological conditions. Preliminary biological results performed using A375 cancer cells show a good tolerability of the functionalized MSNs in the dark and a potentiated activity of DOX upon irradiation, due to the effect of the NO photoreleased

LNL irradiation facilities for radiation damage studies on electronic devices

In this paper we will review the wide range of irradiation facilities installed at the INFN Legnaro National Laboratories and routinely used for radiation damage studies on silicon detectors, electronic components and systems. The SIRAD irradiation facility, dedicated to Single Event Effect (SEE) and bulk damage studies, is installed at the 14MV Tandem XTU accelerator and can deliver ion beams from H up to Au in the energy range from 28MeV to 300 MeV. An Ion Electron Emission Microscope, also installed at SIRAD, allows SEE testing with micrometric sensitivity. For total dose tests, two facilities are presently available: an X-rays source and a 60Co γ-ray source. The 7MV Van de Graaff CN accelerator provides 1H beams in the energy range 2–7MeV and currents up to few μA for both total dose and bulk damage studies. At this facility, very high dose rates (up to ∼100 krad/s (SiO2)) can be achieved. Finally, also neutron beams are available, produced at the CN accelerator, by the reaction d + Be ⇒ n+B

Eficácia do fungo Beauveria bassiana no controle de Drosophila suzukii em cultivos de morango.

Drosophila suzukii, conhecida como SWD é um inseto polígafo que ocasiona danos severos em frutos de pele fina

Measurements of the reaction pˉp→ϕη\bar{p}p \to \phi \eta of antiproton annihilation at rest at three hydrogen target densities

The proton-antiproton annihilation at rest into the $\phi\eta$ final state was measured for three different target densities: liquid hydrogen, gaseous hydrogen at NTP and at a low pressure of 5 mbar. The yield of this reaction in the liquid hydrogen target is smaller than in the low-pressure gas target. The branching ratios of the $\phi\eta$ channel were calculated on the basis of simultaneous analysis of the three data samples. The branching ratio for annihilation into $\phi\eta$ from the $^3S_1$ protonium state turns out to be about ten times smaller as compared to the one from the $^1P_1$ state.Comment: 10 pages, 3 Postscript figures. Accepted by Physics Letters

Hypoxia as a stimulus upon neonatal swinemeniscus cells: highway to phenotypic maturation of meniscal fibro-chondrocytes?

Menisci are essential structures in the knee joint where they cover fundamental biomechanical and protective roles (1-3). Menisci are characterized by a peculiar structure that, on one hand, allow them to perform their particular role in the stifle joint, but simultaneously make them a very challenging structure to deal with (2). Immature menisci are featured by numerously elongated cells (fibrocytes-like) in a disorganized matrix composed almost completely of collagen type I and few glycosaminoglycans (GAGs) and have a rich vascularization, on the other hand, mature and functional menisci are characterized by few round-shaped cells,a matrix rich of well ordinated collagen fibres (above all collagen type II) and GAGs, and preserve vascularization only in the outer zone (aka red zone) (1). Great interest, in both human and veterinary medicines, is reserved to the treatment of the injuries of the inner and avascular zone (aka white zone) of the meniscus: until now, there are no perfect solutions for the regeneration or the replacement of this tissue once injured (3). This work is focused on the utilization of an environmental factor like hypoxia in meniscal tissue culture, in order to evaluate if it could be utilized to improve meniscal culture with a view to tissue engineering. Ninety menisci from neonatal pigs (day 0) were harvested and cultured under two different atmospheric conditions (hypoxia with 1% O2 and normoxia) until 14 days. Samples were analysed at 0, 7 and 14 days through histochemical (Safranin-O staining), immunofluorescence and RT-PCR (Sox-9, Hif-1a, Hif-2, Collagen I and II, both methods) and biochemical (DNA, GAGs, DNA/GAGs ratio) techniques to record any possible differences in maturation of meniscal cells. Safranin-O staining allowed to show an increment in matrix deposition and round-shape \u201cfibro-chondrocytic\u201d cells quantity of hypoxia-cultured menisci respect to controls under normal atmospheric conditions. The same maturation shifting was observed by means of immunofluorescence and RT-PCR analysis, characterized by an increment of Sox-9 and collagen II, moving from day zero to 14-days under hypoxic environment, and by biochemical analysis,with an increment of DNA/GAGs ratio typical of mature meniscal tissue (characterized by few cells and much GAGs). This study shows that hypoxia can be considered as a booster to achieve meniscal cells maturation and opens considerably opportunities in the field of meniscus tissue engineering. References 1. Dai Z, et al. J Orthop Res 2013 ;31:1514-9, 2. Fox AJS, et al. Clin Anat 2015 ;28:269-87 3. Sosio C, et al. Tissue Eng Part A 2015 ;21:3-4

New data on OZI rule violation in bar{p}p annihilation at rest

The results of a measurement of the ratio R = Y(phi pi+ pi-) / Y(omega pi+ pi-) for antiproton annihilation at rest in a gaseous and in a liquid hydrogen target are presented. It was found that the value of this ratio increases with the decreasing of the dipion mass, which demonstrates the difference in the phi and omega production mechanisms. An indication on the momentum transfer dependence of the apparent OZI rule violation for phi production from the 3S1 initial state was found.Comment: 11 pages, 3 PostScript figures, submitted to Physics Letter

Meniscus maturation in the swine model: role of endostatin in cellular differentiation

The development of an engineered meniscus derives from the need to regenerate a tissue which is largely unable to self-repair with consequent loss of functionality. Hence a deeper knowledge of the native meniscus morphology and biomechanics in its different regions, including molecules involved in regulation of the maturation process, is essential. The meniscus is a complex tissue, displaying great regional variation in extracellular matrix components and in vascularization, as a result of several biomechanical stimuli. Its biochemical composition is modulated to adapt the tissue to the different functions that are required throughout growth, until a \u201cmature\u201d phase is reached in adulthood. The aim of this work is to evaluate the biological role of Endostatin in the regulation of angiogenesis as in the fibro-chondrogenic differentiation of neonatal meniscal cells in the pig. The swine is an attractive model for meniscal repair studies, as its knee joint is closely comparable to the human one in terms of anatomical structure, vascularization, and healing potential. Our preliminary data show that Endostatin contributes to the acquisition of chondrocyte phenotype in an undifferentiated but committed cellular population. Thus, a better understanding of the role of Endostatin in cell metabolism might lead to a deeper knowledge of the events regulating meniscus maturation. These findings may be crucial for the development of an engineered scaffold able to induce meniscal cell differentiation by releasing Endostatin-rich microspheres

Ultrastructural and matrix evaluation of morpho-functional age-related changes in dog meniscus

Menisci are essential structures for the knee joint. Different attempts were made trying to replace or regenerate the meniscus after its tear, but the perfect solution is still far away. A better knowledge of the physiologic development of this structure through time could be useful to understand its behavior in the light of the tissue bio-engineering. In this study, the changes in canine meniscal morphology were evaluated to assess how it varies among diverse age stages. The fibers arrangement and matrix deposition in canine menisci from neonatal (died at birth), 10-days, 30-days and adult dogs, dead for causes not related to the present study, were evaluated by means of histochemistry (safranin-O and Sirius red staining), polarized light microscopy, immunofluorescence (collagen I and II) and Scanning Electron Microscopy (SEM). Moreover, quantitative measurements of glycosaminoglycans (GAGs), DNA and GAGs/DNA ratio were performed. The \u201cknotty\u201d structure of neonatal meniscus is probably due to balls of collagen fibres that are not completely stretched until the 30-days stage (Fig 1). The stretching of the fibres starts from the inner portion that is probably the first and the most compressed zone. Safranin-O staining shows how matrix composition vary during growth. Neonatal meniscus is characterized by a huge number of elongated cells (fibroblast-like) and GAGs, features that characterized a still afunctional tissue. With growth, more and more cells assumed a rounded shape. The end-point of the maturation process is represented by the adult meniscus: it is characterized by almost only rounded cells (fibro-chondrocyte-like), in small number, and surrounded by matrix (Fig 1). Nevertheless, 10-30 days interval could be considered the starting point of the meniscus specialization and maturation. Fibres arrangement starts like balls of collagen fibres that follow a disorganized pattern in the neonatal meniscus (Fig 1). In 10-days meniscus, these balls of fibres tend to disappear starting from the meniscus\u2019 inner portion, in association with an initial organization of the fibres according to the longitudinal and radial axes of the meniscus. The organization of fibres network is almost complete at 30-days of life, when all the fibres follow the two main axes of the meniscus and show a well-organized disposition, as seen in adult meniscus. Through the double immunofluorescence it is possible to recognized different aspect of maturation (Fig 3). Neonatal meniscus shows almost only collagen type I fibres. Collagen type I and II co-expression starts at 10 days (yellow) and become more evident in 30-days meniscus in which even a differentiation of the inner and the outer zone starts. The same differentiation persist in adult meniscus that is characterized by a frankly fibro-chondrocitic-like cellular phenotype. Biochemical analysis confirmed that cellularity decrease over the time starting from neonatal to adult (Fig 3). The same decreasing trend is observed in GAGs deposition. Even if 30-days meniscus present a lot of common characteristics with the adult one, the GAGs/DNA ratios show how the latter is the only that present a maturely functional tissue in which a small number of cells is able to produce a matrix rich of GAGs. Meniscal structure changes during growth. The starting point is represented by the neonatal tissue, rich of immature cells and with poor expression of matrix components. The end-point is the adult tissue, characterized by phenotypically mature cells, which assure a functional matrix deposition. Ten-thirty days interval seems to be the turning point of this developmental process. This work highlights how dog meniscal structure changes its morphology among different age stages; this fact may suggest a role of the biomechanical forces, physiologically acting on meniscus, in the development of its ultimate shape and functions. The knowledge of the developmental process of a structure has a capital importance to comprehend its physiologic anatomy and function

First Measurement of Chiral Dynamics in \pi^- \gamma -> \pi^- \pi^- \pi^+

The COMPASS collaboration at CERN has investigated the \pi^- \gamma -> \pi^- \pi^- \pi^+ reaction at center-of-momentum energy below five pion masses, sqrt(s) < 5 m(\pi), embedded in the Primakoff reaction of 190 GeV pions impinging on a lead target. Exchange of quasi-real photons is selected by isolating the sharp Coulomb peak observed at smallest momentum transfers, t' < 0.001 (GeV/c)^2. Using partial-wave analysis techniques, the scattering intensity of Coulomb production described in terms of chiral dynamics and its dependence on the 3\pi-invariant mass m(3\pi) = sqrt(s) were extracted. The absolute cross section was determined in seven bins of $\sqrt{s}$ with an overall precision of 20%. At leading order, the result is found to be in good agreement with the prediction of chiral perturbation theory over the whole energy range investigated.Comment: 10 pages, 5 figure