Maria Alessandra Ragusa

Cellular and molecular effects of protons: Apoptosis induction and potential implications for cancer therapy

Due to their ballistic precision, apoptosis induction by protons could be a strategy to specifically eliminate neoplastic cells. To characterize the cellular and molecular effects of these hadrons, we performed dose-response and time-course experiments by exposing different cell lines (PC3, Ca301D, MCF7) to increasing doses of protons and examining them with FACS, RT-PCR, and electron spin resonance (ESR). Irradiation with a dose of 10 Gy of a 26,7 Mev proton beam altered cell structures such as membranes, caused DNA double strand breaks, and significantly increased intracellular levels of hydroxyl ions, are active oxygen species (ROS). This modified the transcriptome of irradiated cells, activated the mitochondrial (intrinsic) pathway of apoptosis, and resulted in cycle arrest at the G2/M boundary. The number of necrotic cells within the irradiated cell population did not significantly increase with respect to the controls. The effects of irradiation with 20 Gy were qualitatively as well as quantitatively similar, but exposure to 40 Gy caused massive necrosis. Similar experiments with photons demonstrated that they induce apoptosis in a significantly lower number of cells and in a temporally delayed manner. These data advance our knowledge on the cellular and molecular effects of proton irradiation and could be useful for improving current hadrontherapy protocols.

Commutators of fractional integral operators on Vanishing-Morrey spaces

In this note we prove a sufficient condition for commutators of fractional integral operators to belong to Vanishing Morrey spaces VLp,λ. In doing this we use an extension on Morrey spaces of an inequality by Fefferman and Stein concerning the sharp maximal function and the fractional maximal function and related Morrey inequalities.

Immune System Network and Cancer Vaccine

This paper deals with the mathematical modelling of the immune system response to cancer disease, and specifically with the treatment of the mammary carcinoma in presence of an immunoprevenction vaccine. The innate action of the immune system network, the external stimulus represented by repeated vaccine administrations and the competition with cancer are described by an ordinary differential equations‐based model.The mathematical model is able to depict preclinical experiments on transgenic mice. The results are of great interest both in the applied and theoretical sciences.

Partial regularity of p(x)-harmonic maps

Let

Necessary and sufficient condition for a VMO function

(g^{alphabeta}(x))

Hölder Regularity for Solutions of Ultraparabolic Equations in Divergence Form

and

Regularity of solutions of divergence form elliptic equations

(h_{ij}(u))

Commutators of Hardy operators in vanishing Morrey spaces

be uniformly elliptic symmetric matrices, and assume that

Regularity of Minimizers of some Variational Integrals with Discontinuity

h_{ij}(u)

CAUCHY–DIRICHLET PROBLEM ASSOCIATED TO DIVERGENCE FORM PARABOLIC EQUATIONS

and