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Through experimental study of carefully crystallized via long-term thermal annealing alloys using powder X-ray diffraction and differential thermal analysis methods, as well as considering the evidence from the literature, a comprehensive picture of phase equilibria in the Cu2Se-Cu3AsSe4-As2Se3 system was obtained. The projection of the liquidus surface, the isothermal section at 500 K, and three vertical sections of the phase diagram are presented and discussed. The fields of primary crystallization of phases, types, and coordinates of invariant and monovariant phase equilibria are determined. The side Cu2Se-As2Se3 system was re-investigated and its refined phase diagram was constructed. It is shown that this system is quasi-binary and is characterized by the formation of ternary Cu3AsSe3 and CuAsSe2 compounds. [ABSTRACT FROM AUTHOR]

Objectives: We aimed to examine kidney transplant graft survival over 10 years using retrospective analysis., Materials and Methods: Deidentified data of 429 patients extracted from the institution's statistical database were analyzed using descriptive statistics methods and analysis of variance., Results: Graft survival rates at 3, 5, and 10 years were 89.8%, 84.1%, and 81.3%, respectively. Main causes of graft loss were death with a functioning kidney graft and chronic graft nephropathy., Conclusions: In this study, 3-, 5-, and 10-year graft survival rates were satisfactory and similar to the results of other single-center studies in the world. The best survival was observed 3 years after the transplant procedure.

Prolonged pausing of the transcription machinery may lead to the formation of three-stranded nucleic acid structures, called R-loops, typically resulting from the annealing of the nascent RNA with the template DNA. Unscheduled persistence of R-loops and RNA polymerases may interfere with transcription itself and other essential processes such as DNA replication and repair. Senataxin (SETX) is a putative helicase, mutated in two neurodegenerative disorders, which has been implicated in the control of R-loop accumulation and in transcription termination. However, understanding the precise role of SETX in these processes has been precluded by the absence of a direct characterisation of SETX biochemical activities. Here, we purify and characterise the helicase domain of SETX in parallel with its yeast orthologue, Sen1. Importantly, we show that SETX is a bona fide helicase with the ability to resolve R-loops. Furthermore, SETX has retained the transcription termination activity of Sen1 but functions in a species-specific manner. Finally, subsequent characterisation of two SETX variants harbouring disease-associated mutations shed light into the effect of such mutations on SETX folding and biochemical properties. Altogether, these results broaden our understanding of SETX function in gene expression and the maintenance of genome integrity and provide clues to elucidate the molecular basis of SETX-associated neurodegenerative diseases., (© The Author(s) 2023. Published by Oxford University Press on behalf of Nucleic Acids Research.)

R-loops are three-stranded nucleic acid structures composed of an RNA:DNA hybrid and displaced DNA strand. These structures can halt DNA replication when formed co-transcriptionally in the opposite orientation to replication fork progression. A recent study has shown that replication forks stalled by co-transcriptional R-loops can be restarted by a mechanism involving fork cleavage by MUS81 endonuclease, followed by ELL-dependent reactivation of transcription, and fork religation by the DNA ligase IV (LIG4)/XRCC4 complex. However, how R-loops are eliminated to allow the sequential restart of transcription and replication in this pathway remains elusive. Here, we identified the human DDX17 helicase as a factor that associates with R-loops and counteracts R-loop-mediated replication stress to preserve genome stability. We show that DDX17 unwinds R-loops in vitro and promotes MUS81-dependent restart of R-loop-stalled forks in human cells in a manner dependent on its helicase activity. Loss of DDX17 helicase induces accumulation of R-loops and the formation of R-loop-dependent anaphase bridges and micronuclei. These findings establish DDX17 as a component of the MUS81-LIG4-ELL pathway for resolution of R-loop-mediated transcription-replication conflicts, which may be involved in R-loop unwinding., (© The Author(s) 2022. Published by Oxford University Press on behalf of Nucleic Acids Research.)

RECQ5 belongs to the RecQ family of DNA helicases. It is conserved from Drosophila to humans and its deficiency results in genomic instability and cancer susceptibility in mice. Human RECQ5 is known for its ability to regulate homologous recombination by disrupting RAD51 nucleoprotein filaments. It also binds to RNA polymerase II (RNAPII) and negatively regulates transcript elongation by RNAPII. Here, we summarize recent studies implicating RECQ5 in the prevention and resolution of transcription-replication conflicts, a major intrinsic source of genomic instability during cancer development.

The MUS81-EME1 endonuclease cleaves late replication intermediates at common fragile sites (CFSs) during early mitosis to trigger DNA-repair synthesis that ensures faithful chromosome segregation. Here, we show that these DNA transactions are promoted by RECQ5 DNA helicase in a manner dependent on its Ser727 phosphorylation by CDK1. Upon replication stress, RECQ5 associates with CFSs in early mitosis through its physical interaction with MUS81 and promotes MUS81-dependent mitotic DNA synthesis. RECQ5 depletion or mutational inactivation of its ATP-binding site, RAD51-interacting domain, or phosphorylation site causes excessive binding of RAD51 to CFS loci and impairs CFS expression. This leads to defective chromosome segregation and accumulation of CFS-associated DNA damage in G1 cells. Biochemically, RECQ5 alleviates the inhibitory effect of RAD51 on 3'-flap DNA cleavage by MUS81-EME1 through its RAD51 filament disruption activity. These data suggest that RECQ5 removes RAD51 filaments stabilizing stalled replication forks at CFSs and hence facilitates CFS cleavage by MUS81-EME1., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Objectives: Hepatitis B virus remains a serious problem, particularly for patients with end-stage renal disease on maintenance hemodialysis. This study sought to investigate the levels of serum cholestasis markers in hepatitis B virus-positive patients on maintenance hemodialysis., Materials and Methods: This study included 50 hepatitis B virus-positive hemodialysis patients (aged 45.4 ± 4.1 years). All patients had been receiving hemodialysis (because of end-stage renal disease) from 2008 to 2009 at the "MedServis" Private Medical Center in Baku, Azerbaijan. We studied serum gamma-glutamyl transpeptidase and alkaline phosphatase levels after the admission (baseline levels) and after 1, 3, and 6 months of beginning of hemodialysis (or observation for control groups-2). The control groups consisted of hepatitis B virus-negative hemodialysis patients (control group-1) and hepatitis B virus-positive patients with end-stage renal disease not requiring hemodialysis (control group-2)., Results: After 1 and 3 months of hemodialysis, serum gamma-glutamyl transpeptidase and alkaline phosphatase levels gradually declined but remained elevated in hepatitis B virus-positive hemodialysis patients compared to control group-1 and control group-2 patients. After 1 month gamma-glutamyl transpeptidase levels in hepatitis B virus-positive hemodialysis patients were 67.9% lower than baseline levels (P0 < .05), were 51.6% higher compared to control group-2 patients (P1 < .05) and did not differ from control group-1 patients (at the same time points). By month 6, serum alkaline phosphatase levels in hepatitis B virus-positive hemodialysis patients had become 53.9% lower than baseline (P < .01), and did not differ from control group-1 and control group-2 patients., Conclusions: The data obtained in this study suggest that hemodialysis may have a positive effect on cholestasis in end-stage renal disease patients with hepatitis B virus infection, and may increase immune response and improve liver function in this group of patients.

The antihypertensive effects and tolerance of a fixed low-dose combination of the angiotensin-converting enzyme (ACE) inhibitor perindopril (2 mg) and the diuretic indapamide (0.625 mg) were studied in patients with mild and moderate arterial hypertension. The patients' mean age was 51.35 +/- 5.02 years. The antihypertensive effects were evaluated from the results of daily blood pressure monitoring following 12 weeks of therapy. It was found that low-dose combination of perindopril and the indapamide exerted a multidirectional corrective effect on the daily blood pressure (BP): it provided a significant optimal BP lowering during a day on a long-term basis and significantly diminished the baseline increased systolic and diastolic BP variability during a day.