Search results for " Radiation."
showing 10 items of 2788 documents
Radioprotection and Radiomitigation: From the Bench to Clinical Practice.
2020
The development of protective agents against harmful radiations has been a subject of investigation for decades. However, effective (ideal) radioprotectors and radiomitigators remain an unsolved problem. Because ionizing radiation-induced cellular damage is primarily attributed to free radicals, radical scavengers are promising as potential radioprotectors. Early development of such agents focused on thiol synthetic compounds, e.g., amifostine (2-(3-aminopropylamino) ethylsulfanylphosphonic acid), approved as a radioprotector by the Food and Drug Administration (FDA, USA) but for limited clinical indications and not for nonclinical uses. To date, no new chemical entity has been approved by …
Large area conductive nanoaperture arrays with strong optical resonances and spectrally flat terahertz transmission
2017
Using simple and inexpensive nanosphere lithography, we produce large, centimeter-squared sized thin golden films patterned with a hexagonal array of nanoapertures with controllable dimensions on the order of 100–300 nm, spaced by a 350–375 nm pitch distance. The optical transmission spectra of our samples are dominated by the resonant plasmonic features in the spectral range 500–700 nm, caused by the nanostructure in the film. At the same time, the transmission at terahertz (THz) radiation is as high as ∼10% and is spectrally flat. Our measurements are in agreement with finite difference time domain simulations. Such thin metal hole array films allow for very efficient injection of optical…
Depleted uranium induces human carcinogenesis involving the immune and chaperoning systems: Realities and working hypotheses
2019
Abstract Cancer is caused by a combination of factors, genetic, epigenetics and environmental. Among the latter, environmental pollutants absorbed by contact, inhalation, or ingestion are major proven or suspected culprits. Depleted uranium (DU) is one of them directly pertinent to the military and civilians working in militarized areas. It is considered a weak carcinogen but its implication in cancer development in exposed individuals is supported by various data. Since not all subjects exposed to DU develop cancer, it is likely that DU-dependent carcinogenesis requires cofactors, such as genetic predisposition and deficiencies of the chaperoning and immune systems. It is of the essence to…
A study of PD-L1 expression in KRAS mutant non-small cell lung cancer cell lines exposed to relevant targeted treatments.
2017
We investigated PD-L1 changes in response to MEK and AKT inhibitors in KRAS mutant lung adenocarcinoma (adeno-NSCLC). PD-L1 expression was quantified using immunofluorescence and co-culture with a jurkat cell-line transfected with NFAT-luciferase was used to study if changes in PD-L1 expression in cancer cell lines were functionally relevant. Five KRAS mutant cell lines with high PD-L1 expression (H441, H2291, H23, H2030 and A549) were exposed to GI50 inhibitor concentrations of a MEK inhibitor (trametinib) and an AKT inhibitor (AZD5363) for 3 weeks. Only 3/5 (H23, H2030 and A549) and 2/5 cell lines (H441 and H23) showed functionally significant increases in PD-L1 expression when exposed to…
Radiotherapy prolongs the survival of advanced non-smallcell lung cancer patients undergone to an immune-modulating treatment with dose-fractioned ci…
2017
// Pierpaolo Pastina 1 , Valerio Nardone 1 , Cirino Botta 2 , Stefania Croci 1 , Paolo Tini 1 , Giuseppe Battaglia 1 , Veronica Ricci 3 , Maria Grazia Cusi 4 , Claudia Gandolfo 4 , Gabriella Misso 5 , Silvia Zappavigna 5 , Michele Caraglia 5,6 , Antonio Giordano 6,7 , Donatella Aldinucci 8 , Pierfrancesco Tassone 2,6 , Pierosandro Tagliaferri 2 , Luigi Pirtoli 1 and Pierpaolo Correale 1,9 1 Radiotherapy Unit, Department of Medicine, Surgery, and Neuroscience, Siena University Hospital, Siena, Italy 2 Medical Oncology Unit, AUO “Mater Domini”, “Magna Graecia” University, Catanzaro, Italy 3 Radiology Unit,Department of Medicine, Surgery, and Neuroscience, Siena University Hospital, Siena, Ita…
High-Intensity Focused Ultrasound- and Radiation Therapy-Induced Immuno-modulation: Comparison and Potential Opportunities
2017
In recent years, high-intensity focused ultrasound (HIFU) has emerged as a new and promising non-invasive and non-ionizing ablative technique for the treatment of localized solid tumors. Extensive pre-clinical and clinical studies have evidenced that, in addition to direct destruction of the primary tumor, HIFU-thermoablation may elicit long-term systemic host anti-tumor immunity. In particular, an important consequence of HIFU treatment includes the release of tumor-associated antigens (TAAs), the secretion of immuno-suppressing factors by cancer cells and the induction of cytotoxic T lymphocyte (CTL) activity. Radiation therapy (RT) is the main treatment modality used for many types of tu…
Transcriptional Upregulation of DNA Damage Response Genes in Bank Voles (Myodes glareolus) Inhabiting the Chernobyl Exclusion Zone
2018
Exposure to ionizing radiation (IR) from radionuclides released into the environment can damage DNA. An expected response to exposure to environmental radionuclides, therefore, is initiation of DNA damage response (DDR) pathways. Increased DNA damage is a characteristic of many organisms exposed to radionuclides but expression of DDR genes of wildlife inhabiting an area contaminated by radionuclides is poorly understood. We quantified expression of five central DDR genes Atm, Mre11, p53, Brca1, and p21 in the livers of the bank vole Myodes glareolus that inhabited areas within the Chernobyl Exclusion Zone (CEZ) that differed in levels of ambient radioactivity, and also from control areas ou…
Contribution of Excited Ozone and Oxygen Molecules to the Formation of the Stratospheric Ozone Layer
2019
The absorption of UV, visible and near IR radiation by O3 produces transient, electronically excited O3. The absorption of thermal IR radiation ( = 9.065, 9.596 and 14.267 µm) produces vibrationally excited O3 molecules. Thermal absorption is likely the main factor in the self-decay of O3. Photoexcitation of ground state by IR and red light radiation produces singlet oxygens and . Chemical reactions in the stratosphere produce them as well. When reacting with ozone, singlet oxygen produces O (3P) and . By doing so, they tend to maintain the prevailing ozone concentration and are thereby important for the stability of the ozone layer. During the daytime, O(1D), and reach their maximum concen…
Nonlinear femtosecond pulse propagation in an all-solid photonic bandgap fiber
2009
Nonlinear femtosecond pulse propagation in an all-solid photonic bandgap fiber is experimentally and numerically investigated. Guiding light in such fiber occurs via two mechanisms: photonic bandgap in the central silica core or total internal reflection in the germanium doped inclusions. By properly combining spectral filtering, dispersion tailoring and pump coupling into the fiber modes, we experimentally demonstrate efficient supercontinuum generation with controllable spectral bandwidth.
Angular Trapping of Anisometric Nano-Objects in a Fluid
2012
We demonstrate the ability to trap, levitate, and orient single anisometric nanoscale objects with high angular precision in a fluid. An electrostatic fluidic trap confines a spherical object at a spatial location defined by the minimum of the electrostatic system free energy. For an anisometric object and a potential well lacking angular symmetry, the system free energy can further strongly depend on the object's orientation in the trap. Engineering the morphology of the trap thus enables precise spatial and angular confinement of a single levitating nano-object, and the process can be massively parallelized. Since the physics of the trap depends strongly on the surface charge of the objec…