The ataxia telangiectasia mutated and Rad3-related (ATR)-checkpoint kinase 1 (Chk1) axis is the major signaling pathway activated in response to replication stress and is essential for the intra-S checkpoint. ATR phosphorylates and activates a number of molecules to coordinate cell cycle progression. Chk1 is the major effector downstream from ATR and plays a critical role in intra-S checkpoint ...

Cellular senescence is a phenotype that is likely linked with aging. Recent concepts view different forms of senescence as permanently maintained DNA damage responses partially characterized by the presence of senescence-associated DNA damage foci at dysfunctional telomeres. Irradiation of primary human dermal fibroblasts with the photosensitizer 8-methoxypsoralen and ultraviolet A radiation (P...

The major cytotoxic DNA adduct induced by temozolomide and other methylating agents used in malignant glioma and metastasized melanoma therapy is O-methylguanine (O-MeG). This primary DNA damage is converted by mismatch repair into secondary lesions, which block replication and in turn induce DNA double-strand breaks that trigger the DNA damage response (DDR). Key upstream players in the DDR ar...

purpose : to determine the association between astigmatism and spherical refractive error in a clinical population methods : in this cross-sectional study, 2,000 patients who presented to our optometry clinic were enrolled. all were tested for objective refraction with a nidek ar-310a auto refractometer, and non-cycloplegic refraction. for those under 15 years of age, cycloplegic refraction was...

A sound multi-species vegetation buffer design should incorporate the species that facilitate rapid degradation and sequestration of deposited herbicides in the buffer. A field lysimeter study with six different ground covers (bare ground, orchardgrass, tall fescue, timothy, smooth bromegrass, and switchgrass) was established to assess the bioremediation capacity of five forage species to enhan...

Background: Atrazine (ATR) is used as an agriculture herbicide worldwide. It has been shown that ATR adversely affect the reproductive system in rodents. In this study we aimed to evaluate the impact of chronic exposure to Atrazine (ATR) on male testicular tissue, sperm parameters, serum level of total thiol molecules (TTM) and malodialdehyde (MDA) content of testes. Methods: To follow-up th...

Automatic target recognition (ATR) is a computationally intensive problem that benefits from the abilities of the Connection Machine (CM), a massively parallel computer used for data-level parallel computing. The large computational resources of the CM can efficiently handle an approach to ATR that uses parallel stereo-matching and neural-network algorithms. Such an approach shows promise as an...

The ataxia telangiectasia mutated serine/threonine kinase (ATM)/checkpoint kinase 2 (CHEK2, best known as CHK2) and the ATM and Rad3-related serine/threonine kinase (ATR)/CHEK1 (best known as CHK1) cascades are the 2 major signaling pathways driving the DNA damage response (DDR), a network of processes crucial for the preservation of genomic stability that act as a barrier against tumorigenesis...

We aimed to evaluate the effect of melatonin on myo-cardial cell oncosis in the myocardial ischemia/reperfusion injury rat, and the role of the mitochondrial permeability transition pore (MPTP) therein. Sprague Dawley rats (N = 60) were randomly divided into five groups of 12 rats each: control, ischemia/reperfusion (I/R), melatonin treatment (MT), melatonin treatment + atractyloside (MT+ATR), ...

background and objectives: attenuated total reflectance-inferared (atr-ir) spectra can be used as a non-invasive fingerprinting approach in quality control of herbal samples. methods: twenty versatile herbal samples were subjected to attenuated total reflectance-inferared (atr-ir) spectroscopy followed by different clustering methods in order to determine by which method more reasonable classif...