The cytotoxic effects of alkylating agents are strongly attenuated by cellular DNA repair processes, necessitating a clear understanding of the repair mechanisms. Simple methylating agents form adducts at N- and O-atoms. N-methylations are removed by base excision repair, AlkB homologues, or nucleotide excision repair (NER). O(6)-methylguanine (MeG), which can eventually become cytotoxic and mu...

Skin cancer is the most common form of cancer in the United States. The main cause of this cancer is DNA damage induced by the UV component of sunlight. In humans and mice, UV damage is removed by the nucleotide excision repair system. Here, we report that a rate-limiting subunit of excision repair, the xeroderma pigmentosum group A (XPA) protein, and the excision repair rate exhibit daily rhyt...

The global regulator H-NS of Escherichia coli controls genes related to stress response, biofilm formation and virulence by recognizing curved DNA and by silencing acquired genes. Here, we rewired H-NS to control biofilm formation using protein engineering; H-NS variant K57N was obtained that reduces biofilm formation 10-fold compared with wild-type H-NS (wild-type H-NS increases biofilm format...

Heteroduplex deoxyribonucleic acid molecules having a drug resistance marker on one strand and its wild-type allele on the other have been used as donors in pneumococcal transformation. Opposite strands are not equally effective in producing transformants, and this strand bias is not the same, either in direction or magnitude, for various different genetic markers. Selective excision of mismatc...

BACKGROUND Cystic hygroma is a rare benign abnormality of the lymphatic system generally occurring in young children less than 2 years old. The standard transcervical surgical treatment of cystic hygroma may often leave a permanent scar in the neck region. CASE PRESENTATION We report a case of cystic hygroma in a 19-month-old Asian baby girl successfully treated with robot-assisted excision t...

DNA methylation is a primary epigenetic modification regulating gene expression and chromatin structure in many eukaryotes. Plants have a unique DNA demethylation system in that 5-methylcytosine (5mC) is directly removed by DNA demethylases, such as DME/ROS1 family proteins, but little is known about the downstream events. During 5mC excision, DME produces 3'-phosphor-α, β-unsaturated aldehyde ...

An interference excision algorithm in direct-sequence spread spectrum (DS-SS) communication systems is introduced. The proposed excision algorithm is developed for linear frequency modulated (LFM) signals that have broadband frequency characteristics. It is based on the time-frequency analysis of received signals employing short-time Fourier transformation (STFT). To analyze the interference, S...

AIMS To investigate the histopathological reporting of basal cell carcinoma. METHODS Methods of classification and attitudes to excision margins were ascertained from histopathologists in 130 centres; 82 replies were obtained (63% response rate). RESULTS 24% of those replying did not use any classification system for basal cell carcinoma. The remainder (76%) used a wide variety of different...

STUDY DESIGN A new surgical strategy for treatment of patients with spinal metastases was designed, and 61 patients were treated based on this strategy. OBJECTIVES To propose a new surgical strategy for the treatment of patients with spinal metastases. SUMMARY OF BACKGROUND DATA A preoperative score composed of six parameters has been proposed by Tokuhashi et al for the prognostic assessmen...