Dynamic Changes in DNA Damage and Repair Biomarkers with Employment Length among Nickel Smelting Workers

Our study explored the dynamic changes in andthe relationship between the DNA damage marker8-hydroxy-2＇-deoxyguanosine （8-OHdG） and theDNA repair marker 8-hydroxyguanine DNAglycosidase 1 （hOGG1） according to the length ofoccupational employment in nickel smeltingworkers. One hundred forty nickel-exposedsmelting workers and 140 age-matched unexposedoffice workers were selected from the Jinchangcohort. The 8-OHdG levels in smelting workers wassignificantly higher than in office workers （Z=-8.688,P〈0.05） and the 8-OHdG levels among nickelsmelting workers in the 10-14 y employment lengthcategory was significantly higher than among allpeers. The hOGG1 levels among smelting workerswere significantly lower than those of non-exposedworkers （Z=-8.948, P〈0.05）. There were significantdifferences between employment length andhOGG1 levels, with subjects employed in nickelsmelting for 10-14 y showing the highest levels ofhOGG1. Correlation analysis showed positivecorrelations between 8-OHdG and hOGG1 levels（r=0.413; P〈0.01）. DNA damage was increased withemployment length among nickel smelting workersand was related to the inhibition of hOGG1 repaircapacity.

Design and Verification of Selected Technological Procedures for the Repairs of Land Vehicles Combat Damage

The paper deals with temporary repairs. Applying a different technology, using a reproduction part, or performing a repair by a serviceman without the competence is typical features of temporary repairs. Temporary repair makes possible for an object to fulfil its function for a limited time, until regular repairs can be made. The complexity perplex modern vehicles their reparability. It is necessary to look for the new procedures of the implementation so-called temporary repairs. The authors suggested procedure battle damage assessment and repair, which they expressed in the form of diagrams. There is also description of new technological procedures, which could be possibly applied in field of temporary repairs. These new procedures are applied on land (wheeled and tracked) vehicles parts and their sufficiency for Czech Army conditions is tested. The main purpose of the thesis is defining operating procedures of the most useful methods, including their verifications and proposal of tools needed for repairs. These tools should be included in equipment of vehicles operated in Czech Army. The thesis is primarily focused on repairs of mechanical parts and units and also of reparation of fuel, hydraulic and high pressure systems.

DNA plasticity and damage in amyotrophic lateral sclerosis

The pathophysiology of amyotrophic lateral sclerosis （ALS） is particularly challenging due to the heteroge- neity of its clinical presentation and the diversity of cellular, molecular and genetic peculiarities involved. Molecular insights unveiled several novel genetic factors to be inherent in both familial and sporadic dis- ease entities, whose characterizations in terms of phenotype prediction, pathophysiological impact and putative prognostic value are a topic of current researches. However, apart from genetically well-defined high-confidence and other susceptibility loci, the role of DNA damage and repair strategies of the genome as a whole, either elicited as a direct consequence of the underlying genetic mutation or seen as an autono- mous parameter, in the initiation and progression of ALS, and the different cues involved in either process are still incompletely understood. This mini review summarizes current knowledge on DNA alterations and counteracting DNA repair strategies in ALS pathology and discusses the putative role of unconventional DNA entities including transposable elements and extrachromosomal circular DNA in the disease process. Focus is set on SODl-related pathophysiology, with extension to FUS, TDP-43 and C90RF72 mutations. Advancing our knowledge in the field will contribute to an improved understanding of this relentless dis- ease, for which therapeutic options others than symptomatic approaches are almost unavailable.

The interplay of cell cycle and DNA repair gene alterations in upper tract urothelial carcinoma:predictive and prognostic implications

Upper tract urothelial carcinoma(UTUC)is rare but can occur sporadically outside the context of Lynch syndrome.In these cases,knowing whether non-mismatch repair(MMR),DNA damage response and repair(DDR),and cell cycle gene alterationsmay predict responses to chemotherapy orimmunotherapy and survival is of clinical importance.This study examined the germline and somatic mutational landscape of two UTUC patients with differential responses to programmed death 1(PD-1)/PD-ligand 1(PD-L1)immune checkpoint inhibitors and queried three independent UTUC cohort studies for co-occurrence of key cell cycle and DDR genes,as well as for their associations with overall survival(OS).TP53 and RB1 emerged as potential determinants of shorter OS in UTUC cohort patients,regardless of concurrent DDR alterations,and if prospectively assessed in larger studies they might also explain resistance to PD-1/PD-L1 blockade despite PD-L1 expression.

Emerging role of nuclear factor erythroid 2-related factor 2 in the mechanism of action and resistance to anticancer therapies

Nuclear factor E2-related factor 2(NRF2),a transcription factor,is a master regulator of an array of genes related to oxidative and electrophilic stress that promote and maintain redox homeostasis.NRF2 function is well studied in in vitro,animal and general physiology models.However,emerging data has uncovered novel functionality of this transcription factor in human diseases such as cancer,autism,anxiety disorders and diabetes.A key finding in these emerging roles has been its constitutive upregulation in multiple cancers promoting pro-survival phenotypes.The survivability pathways in these studies were mostly explained by classical NRF2 activation involving KEAP-1 relief and transcriptional induction of reactive oxygen species(ROS)neutralizing and cytoprotective drug-metabolizing enzymes(phase I,II,III and 0).Further,NRF2 status and activation is associated with lowered cancer therapeutic efficacy and the eventual emergence of therapeutic resistance.Interestingly,we and others have provided further evidence of direct NRF2 regulation of anticancer drug targets like receptor tyrosine kinases and DNA damage and repair proteins and kinases with implications for therapy outcome.This novel finding demonstrates a renewed role of NRF2 as a key modulatory factor informing anticancer therapeutic outcomes,which extends beyond its described classical role as a ROS regulator.This review will provide a knowledge base for these emerging roles of NRF2 in anticancer therapies involving feedback and feed forward models and will consolidate and present such findings in a systematic manner.This places NRF2 as a key determinant of action,effectiveness and resistance to anticancer therapy.