INTRODUCTION Proton radiation offers physical advantages over conventional radiation. Radiosensitivity of human 59M ovarian cancer and HTB140 melanoma cells was investigated after exposure to γ-rays and protons. MATERIAL AND METHODS Irradiations were performed in the middle of a 62 MeV therapeutic proton spread out Bragg peak with doses ranging from 2 to 16 Gy. The mean energy of protons was ...

The binding of the anti-cancer drug pixantrone to three oligonucleotide sequences, d(TCATATGA)2, d(CCGAGAATTCCGG)2 {double bulge = DB} and the non-self complementary d(TACGATGAGTA) : d(TACCATCGTA) {single bulge = SB}, has been studied by NMR spectroscopy and molecular modelling. The upfield shifts observed for the aromatic resonances of pixantrone upon addition of the drug to each oligonucleoti...

Protons from hydrogen or water vapour may dissolve in oxides and other corrosion products, and may affect, and in some cases, dominate their defect structures. Defect-dependent properties like scale growth and plastic deformation then become dependent on the ambient hydrogen or water vapour pressure. Small concentrations of protons may enhance the transport of oxygen in the form of hydroxide io...

1. Space Radiation Environment and Modeling • The Earth’s geomagnetic field and its effect on high-energy, ionizing particles including electrons, protons, and some heavy ions • The Earth's trapped radiation environment and Trapped radiation models, the characteristics of the Van Allen belts and South Atlantic Anomaly • Effects of trapped radiation on spacecraft and components • Space Weather c...

We show that the rising total photoproduction cross section recently observed at HERA is entirely consistant with the impact-picture in the theory of expanding protons which was proposed more than twenty years ago. More accurate data, which is expected to be forthcoming soon, will give this prediction a stringent test. Key-Words : Total photon cross section, impact-picture. Number of figures : ...

There will be a review of the history of polarized proton beams, and a discussion of the unexpected and still unexplained large transverse spin effects found in several high energy proton-proton spin experiments at the ZGS, AGS and Fermilab. Next, there will be a discussion of present and possible future experiments on the violent elastic collisions of polarized protons at IHEP-Protvino’s 70 Ge...

The anti-ulcer drugs that act as covalent inhibitors of the gastric acid pump are targeted to the gastric H+/K+ ATPase by virtue of accumulation in acid and conversion to the active sulfenamide. This results in extremely effective inhibition of acid secretion. Appropriate dosage is able to optimize acid control therapy for reflux and peptic ulcer disease as compared to H2 receptor antagonists. ...

Introduction: High-energy beams of protons offer significant advantages for the treatment of deepseated local tumors. Their physical depth-dose distribution in tissue is characterized by a small entrance dose and a distinct maximum -Bragg peak- near the end of range with a sharp fall-off at the distal edge. Alongside its advantages there are some point that they need to meticul...

Using the tritium Sephadex method, the number of exchangeable protons in E. coli 5S RNA and the kinetics of their exchange reactions have been measured at two different Mg++ concentrations (10(-2) M and 10(-3) M). A quantitative analysis of these results indicates the presence of two classes of protons exchanging with very different rates. The protons of the slow class, not seen in linear molec...

The rates of H-D exchange for imino and amino protons in adenosine, calf thymus DNA, poly (dA-dT), poly(dG-dC), and poly (dG-me5dC) were determined using stopped flow kinetic methods in the presence of various concentrations of Tris, imidazole, Mg2+, and spermine in citrate buffer (pH 7, 25 degrees C). CD spectroscopic studies showed that all polynucleotides always remain in the B-form under th...