44 research outputs found
The Hidden Quantum Groups Symmetry of Super-renormalizable Gravity
In this paper we consider the relation between the super-renormalizable
theories of quantum gravity (SRQG) studied in [arXiv:1110.5249v2,
arXiv:1202.0008] and an underlying non-commutativity of spacetime. For one
particular super-renormalizable theory we show that at linear level (quadratic
in the Lagrangian) the propagator of the theory is the same we obtain starting
from a theory of gravity endowed with {\theta}-Poincar\'e quantum groups of
symmetry. Such a theory is over the so called {\theta}-Minkowski non-commuative
spacetime. We shed new light on this link and show that among the theories
considered in [arXiv:1110.5249v2, arXiv:1202.0008], there exist only one
non-local and Lorentz invariant super-renormalizable theory of quantum gravity
that can be described in terms of a quantum group symmetry structure. We also
emphasize contact with pre-existent works in the literature and discuss
preservation of the equivalence principle in our framework.Comment: 10 page
Fock space, quantum fields and kappa-Poincar\'e symmetries
We study the quantization of a linear scalar field, whose symmetries are
described by the kappa-Poincare' Hopf-algebra, via deformed Fock space
construction. The one-particle sector of the theory exhibits a natural
(planckian) cut-off for the field modes. At the multi-particle level the
non-trivial co-algebra structure of kappa-Poincare' leads to a deformed
bosonization in the construction of Fock space states. These physical states
carry energy-momentum charges which are divergenceless and obey a deformed
dispersion relation.Comment: RevTeX, 17 pages, 5 figure
Medium-Term Culture of Primary Oral Squamous Cell Carcinoma in a Three-Dimensional Model: Effects on Cell Survival Following Topical 5-Fluororacile Delivery by Drug-Loaded Matrix Tablets
Since the activity of several conventional anticancer drugs is restricted by resistance mechanisms and dose-limiting side-effects, the design of formulations for local application on malignant lesions seems to be an efficient and promising drug delivery approach. In this study, the effect of locally applied 5-FU on cell death was evaluated both in a SCC4/HEK001 model and in a newly proposed 3D outgrowth model of oral squamous cell carcinoma (OSCC). Initially, the optimal drug dose was established by delivery of solutions containing different amounts of 5-FU. The solution containing 1% (w/v) of 5-FU resulted effective in inducing cell death with complete eradication of cell colonies. Buccal tablets were designed to deliver 5-FU locoregionally to the cancer lesions of the oral cavity. Tablets were prepared using a drug loaded matrix of acrylic/methacrylic acid copolymer containing 1% (w/w) of 5-FU and applied on 3D outgrowths. The drug release from tablets appeared to be sufficient to induce cell death as confirmed by transmission electron microscopy and enzymatic assay (TUNEL). After 120 h of treatment, when about 90% of the drug had been discharged from the tablets into the culture environment, 5-FU caused loss of cell-cell communications and apoptotic cell death. After 192 h, a complete disaggregation of the 3D oral outgrowths and the death of all the cells was observed. Buccal matrix tablets could be considered a promising new approach to the locoregional treatment of OSCC. Risks of systemic toxicity are avoided since very low drug doses are delivered
Prevalence of Use and Cost of Biological Drugs for Cancer Treatment: A 5-Year Picture from Southern Italy
Background and Objectives: Considering the clinical and economic burden of biological drugs in cancer treatment, it is necessary to explore how these drugs are used in routine care in Italy and how they affect the sustainability of the National Health Services. This study aimed to investigate the prevalence of use and costs of biological drugs for cancer treatment in a general population of Southern Italy in the years 2010â2014. Methods: This was a retrospective, observational study using data from the healthcare administrative databases of Messina Province for the years 2010â2014. In this study, users of biological drugs for cancer treatment were characterized and the prevalence of use and costs were calculated over time. The potential impact of biosimilars on the expenditure was also estimated. Results: Of a population of 653,810 residents in the Messina area during the study years, 2491 (0.4%) patients received at least one study drug. The most frequently used were monoclonal antibodies (mAbs) (n = 1607; 64.5%) and tyrosine kinase inhibitors (TKIs) (n = 609; 24.4%). mAbs were mainly used by females (60.3%) for metastasis due to an unspecified primary tumor, lymphomas, or breast cancer (24.2, 16.7, and 13.7%, respectively). Most users of small molecules were males (56.3%) being treated for multiple myeloma, metastasis due to unspecified primary tumor, leukemia, and lung cancer (13.1, 12.6, 9.5, and 8.9%, respectively). During the study years, the prevalence of use doubled from 0.9 to 1.8 per 1000 inhabitants; likewise, the related expenditure grew from âŹ6.6 to âŹ13.6 million. Based on our forecasts, this expenditure will grow to âŹ25 million in 2020. Assuming a 50% biosimilar uptake (trastuzumab and rituximab), a potential yearly saving of almost âŹ1 million may be achieved. Conclusions: In recent years, the use and costs of biological drugs in cancer patients have increased dramatically in a large population from Southern Italy. This trend may be counterbalanced by adopting biosimilars once they are available. Claims databases represent a valid tool to monitor the uptake of newly marketed biological drugs and biosimilars
Comparative Effectiveness of Biosimilar, Reference Product and Other Erythropoiesis-Stimulating Agents (ESAs) Still Covered by Patent in Chronic Kidney Disease and Cancer Patients: An Italian Population-Based Study
Background Since 2007 biosimilars of erythropoiesis-stimulating agents (ESAs) are available on the Italian market. Very limited post-marketing data exist on the comparative effectiveness of biosimilar and originator ESAs. Aim This population-based study was aimed to compare the effects of biosimilars, reference product and other ESAs still covered by patent on hemoglobinemia in chronic kidney disease (CKD) and cancer patients in a Local Health Unit (LHU) from Northern Italy. Methods A retrospective cohort study was conducted during the years 2009-2014 using data from Treviso LHU administrative database. Incident ESA users (no ESA dispensing within 6 months prior to treatment start, i.e. index date (ID)) with at least one hemoglobin measurement within one month prior to ID (baseline Hb value) and another measurement between 2nd and 3rd month after ID (follow-up Hb value) were identified. The strength of the consumption (as total number of defined daily dose (DDD) dispensed during the follow-up divided by days of follow-up) and the difference between follow-up and baseline Hb values [delta Hb (ÎHb)] were evaluated. Based on Hb changes, ESA users were classified as non-responders (ÎHbâ¤0 g/dl), responders (0Delta;Hbâ¤2 g/dl), and highly responders (ÎHb>2 g/ dl). A multivariate ordinal logistic regression model to identify predictors for responsiveness to treatment was performed. All analyses were stratified by indication for use and type of dispensed ESA at ID. Results Overall, 1,003 incident ESA users (reference product: 252, 25.1%; other ESAs covered by patent: 303, 30.2%; biosimilars: 448, 44.7%) with CKD or cancer were eligible for the study. No statistically significant difference in the amount of dose dispensed during the follow-up among biosimilars, reference product and other ESAs covered by patent was found in both CKD and cancer. After three months from treatment start, all ESAs increased Hb values on average by 2g/dl. No differences in ÎHb as well as in frequency of non-responders, responders and highly responders among different types of ESAs were observed in both indications of use. Overall, around 15-20% of ESA users were non-responders. Strength of treatment, but no type of dispensed ESAs was found to be predictor of responsiveness to treatment. Conclusions No difference on the effects on hemoglobinemia among users of either biosimilars or reference product or ESAs covered by patent was observed in a general population from Northern Italy, despite a comparable dispensed dose of the different ESAs during the first three months of treatment
Author Correction to: Prevalence of Use and Cost of Biological Drugs for Cancer Treatment: A 5-Year Picture from Southern Italy
Unfortunately, many errors were identified in the published article. The original article was corrected
Hsp60 Is Actively Secreted by Human Tumor Cells
Background: Hsp60, a Group I mitochondrial chaperonin, is classically considered an intracellular chaperone with residence in the mitochondria; nonetheless, in the last few years it has been found extracellularly as well as in the cell membrane. Important questions remain pertaining to extracellular Hsp60 such as how generalized is its occurrence outside cells, what are its extracellular functions and the translocation mechanisms that transport the chaperone outside of the cell. These questions are particularly relevant for cancer biology since it is believed that extracellular chaperones, like Hsp70, may play an active role in tumor growth and dissemination. Methodology/Principal Findings: Since cancer cells may undergo necrosis and apoptosis, it could be possible that extracellular Hsps are chiefly the result of cell destruction but not the product of an active, physiological process. In this work, we studied three tumor cells lines and found that they all release Hsp60 into the culture media by an active mechanism independently of cell death. Biochemical analyses of one of the cell lines revealed that Hsp60 secretion was significantly reduced, by inhibitors of exosomes and lipid rafts. Conclusions/Significance: Our data suggest that Hsp60 release is the result of an active secretion mechanism and, since extracellular release of the chaperone was demonstrated in all tumor cell lines investigated, our observations most likel
Quantum gravity phenomenology at the dawn of the multi-messenger eraâA review
The exploration of the universe has recently entered a new era thanks to the multi-messenger paradigm, characterized by a continuous increase in the quantity and quality of experimental data that is obtained by the detection of the various cosmic messengers (photons, neutrinos, cosmic rays and gravitational waves) from numerous origins. They give us information about their sources in the universe and the properties of the intergalactic medium. Moreover, multi-messenger astronomy opens up the possibility to search for phenomenological signatures of quantum gravity. On the one hand, the most energetic events allow us to test our physical theories at energy regimes which are not directly accessible in accelerators; on the other hand, tiny effects in the propagation of very high energy particles could be amplified by cosmological distances. After decades of merely theoretical investigations, the possibility of obtaining phenomenological indications of Planck-scale effects is a revolutionary step in the quest for a quantum theory of gravity, but it requires cooperation between different communities of physicists (both theoretical and experimental). This review, prepared within the COST Action CA18108 âQuantum gravity phenomenology in the multi-messenger approachâ, is aimed at promoting this cooperation by giving a state-of-the art account of the interdisciplinary expertise that is needed in the effective search of quantum gravity footprints in the production, propagation and detection of cosmic messengers.publishedVersio
Quantum gravity phenomenology at the dawn of the multi-messenger era -- A review
The exploration of the universe has recently entered a new era thanks to the
multi-messenger paradigm, characterized by a continuous increase in the
quantity and quality of experimental data that is obtained by the detection of
the various cosmic messengers (photons, neutrinos, cosmic rays and
gravitational waves) from numerous origins. They give us information about
their sources in the universe and the properties of the intergalactic medium.
Moreover, multi-messenger astronomy opens up the possibility to search for
phenomenological signatures of quantum gravity. On the one hand, the most
energetic events allow us to test our physical theories at energy regimes which
are not directly accessible in accelerators; on the other hand, tiny effects in
the propagation of very high energy particles could be amplified by
cosmological distances. After decades of merely theoretical investigations, the
possibility of obtaining phenomenological indications of Planck-scale effects
is a revolutionary step in the quest for a quantum theory of gravity, but it
requires cooperation between different communities of physicists (both
theoretical and experimental). This review is aimed at promoting this
cooperation by giving a state-of-the art account of the interdisciplinary
expertise that is needed in the effective search of quantum gravity footprints
in the production, propagation and detection of cosmic messengers