The ability of the flavan kazinol Q (KQ) to induce DNA breakage in the presence of Cu(II) was examined by agarose gel electrophoresis using supercoiled plasmid DNA. In KQ-mediated DNA breakage reaction, the involvement of reactive oxygen species (ROS), H(2)O(2) and O(2)- was established by the inhibition of DNA breakage by catalase and revealed DNA breakage by superoxide dismutase (SOD). The ce...

BACKGROUND Condoms are effective in preventing the transmission of HIV and other sexually transmitted infections, when properly used. However, recent data from surveys of female sex workers (FSWs) in Karnataka in south India, suggest that condom breakage rates may be quite high. It is important therefore to quantify condom breakage rates, and examine what factors might precipitate condom breaka...

In this paper we study breakage rate statistics of small colloidal aggregates in nonhomogeneous anisotropic turbulence. We use pseudospectral direct numerical simulation of turbulent channel flow and Lagrangian tracking to follow the motion of the aggregates, modeled as sub-Kolmogorov massless particles. We focus specifically on the effects produced by ductile rupture: This rupture is initially...

PATIENT A 74-year-old woman visited our hospital with a chief complaint of masticatory dysfunction due to upper left molar denture breakage and poor retention of upper and lower dentures. The cause of the denture breakage was a lack of clearance, and that of denture instability was the unilateral design in the upper jaw, and breakage of the indirect retainer in the lower jaw. The treatment plan...

Breakage-fusion-bridge cycles in cancer arise when a broken segment of DNA is duplicated and an end from each copy joined together. This structure then 'unfolds' into a new piece of palindromic DNA. This is one mechanism responsible for the localised amplicons observed in cancer genome data. Here we study the evolution space of breakage-fusion-bridge structures in detail. We firstly consider di...

We extend the McPherson model for Si-O bond-breakage energetics, which considers only a single SiO4 tetrahedron, in a way to capture the effect of the whole crystal. No ledge in the direction assumed in the McPherson model was revealed. Instead, potential profiles feature a saddle point in a different direction. The activation energy for bond-breakage is found to be rather high (~ 6 eV). This s...

ATR, activated by replication stress, protects replication forks locally and suppresses origin firing globally. Here, we show that these functions of ATR are mechanistically coupled. Although initially stable, stalled forks in ATR-deficient cells undergo nucleus-wide breakage after unscheduled origin firing generates an excess of single-stranded DNA that exhausts the nuclear pool of RPA. Partia...

INTRODUCTION Breakage of the screws which may cause non-union or collapse of vertebral structures has been a complication of the pedicle screw fixation at a rate of 3-7 % [1-2]. Recently, flexible rods have been used for dynamic stabilization to avoid complications such as adjacent segment degeneration due to excessive stiffness of the spinal fusion by allowing intersegmental motion at the surg...

Breakage of overhead transmission lines and distribution will lead to severe power outage problems, clarifying the breakage mechanism is great importance value for reliability stability system. Taking ground wire example, this paper presents its study under lighting stoke based on finite element analysis. A multi-physics analysis model built first, which includes contact points. The current den...