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Abstract Histone H2AX plays a key role in DNA damage signalling in the surrounding regions of DNA double-strand breaks (DSBs). In response to DNA damage, H2AX becomes phosphorylated on serine residue 139 (known as γH2AX), resulting in the recruitment of the DNA repair effectors 53BP1 and BRCA1. Here, by studying resistance to poly(ADP-ribose) polymerase (PARP) inhibitors in BRCA1/2-deficient mammary tumours, we identify a function for γH2AX in orchestrating drug-induced replication fork degradation. Mechanistically, γH2AX-driven replication fork degradation is elicited by suppressing CtIP-mediated fork protection. As a result, H2AX loss restores replication fork stability and increases chemoresistance in BRCA1/2-deficient tumour cells without restoring homology-directed DNA repair, as highlighted by the lack of DNA damage-induced RAD51 foci. Furthermore, in the attempt to discover acquired genetic vulnerabilities, we find that ATM but not ATR inhibition overcomes PARP inhibitor (PARPi) resistance in H2AX-deficient tumours by interfering with CtIP-mediated fork protection. In summary, our results demonstrate a role for H2AX in replication fork biology in BRCA-deficient tumours and establish a function of H2AX separable from its classical role in DNA damage signalling and DSB repair.

YBa2Cu3Ox (YBCO) thin films were deposited on 14°–22° tilted-axes NdGaO3 (NGO) substrates with pulsed laser deposition. Two orientations of the film are possible due to the presence of symmetrically equivalent (110) and (1 − 1 0) facets on the substrate surface. At high deposition rates, the pseudo-a grains, (100)YBCO||(110)NGO, gradually overgrow the pseudo-c grains, (001)YBCO||(110)NGO, forming high-tilted (tilt angle of the c axis 69°–74°) YBCO films. The substrate tilt angles in the vicinity of 18.43° promote formation of high-tilted films as a result of graphoepitaxial seeding of the pseudo-a grains on the (110) facets on the substrate surface due to the matching of the c lattice constant of the film with the length of the (110) terraces on the substrate surface. The effect of graphoepitaxial seeding was observed for the substrate tilt angles in the range 16°–21°, probably due to undulating edges of steps on the substrate surface. An increase of the deposition rate above a threshold level of ~ 3 nm/s results in a change of the growth mode with the formation of films with smooth surface morphology. The probable reason is a transition from vapor phase epitaxy to vapor–liquid–solid crystallization mechanism. The tilted-axes YBCO films demonstrate superconducting transition temperature superior to standard samples fabricated on (110) NGO substrates. The width of the superconducting transition for tilted-axes films increases due to the suppression of the critical current in the direction normal to the tilt axis. [ABSTRACT FROM AUTHOR]

Objective: The study analyses the number, characteristics and reasons for a length of stay of patients in German psychiatric clinics in excess of 6 months., Methods: The study was implemented in the form of a nationwide online survey, which was addressed to chief physicians of psychiatric clinics., Results: In the sample, 174 patients in 80 psychiatric clinics were identified who could not be discharged because no suitable follow-up services were available in the region. The majority of patients are male, often have an F2 diagnosis and exhibit aggressive behaviour during their hospital stay., Conclusion: To avoid inappropriate health care and prevent prolonged stays for a subgroup of mentally ill people, individual complex services should be implemented in community psychiatry., Competing Interests: Die Autorinnen/Autoren geben an, dass kein Interessenkonflikt besteht., (Thieme. All rights reserved.)

Homologous recombination (HR) is a highly conserved tool for the removal of DNA double-strand breaks (DSBs) and the preservation of stalled and damaged DNA replication forks. Successful completion of HR requires the tumor suppressor BRCA2. Germline mutations in BRCA2 lead to familial breast, ovarian, and other cancers, underscoring the importance of this protein for maintaining genome stability. BRCA2 harbors two distinct DNA binding domains, one that possesses three oligonucleotide/oligosaccharide binding (OB) folds (known as the OB-DBD), and with the other residing in the C-terminal recombinase binding domain (termed the CTRB-DBD) encoded by the last gene exon. Here, we employ a combination of genetic, biochemical, and cellular approaches to delineate contributions of these two DNA binding domains toward HR and the maintenance of stressed DNA replication forks. We show that OB-DBD and CTRB-DBD confer ssDNA and dsDNA binding capabilities to BRCA2, respectively, and that BRCA2 variants mutated in either DNA binding domain are impaired in the ability to load the recombinase RAD51 onto ssDNA pre-occupied by RPA. While the CTRB-DBD mutant is modestly affected for HR, it exhibits a strong defect in the protection of stressed replication forks. In contrast, the OB-DBD is indispensable for both BRCA2 functions. Our study thus defines the unique contributions of the two BRCA2 DNA binding domains in genome maintenance.

Caspase activated DNase (CAD) induced DNA breaks promote cell differentiation and therapy-induced cancer cell resistance. CAD targeting activity is assumed to be unique to each condition, as differentiation and cancer genesis are divergent cell fates. Here, we made the surprising discovery that a subset of CAD-bound targets in differentiating muscle cells are the same genes involved in the genesis of cancer-causing translocations. In muscle cells, a prominent CAD-bound gene pair is Pax7 and Foxo1a, the mismatched reciprocal loci that give rise to alveolar rhabdomyosarcoma. We show that CAD-targeted breaks in the Pax7 gene are physiologic to reduce Pax7 expression, a prerequisite for muscle cell differentiation. A cohort of these CAD gene targets are also conserved in early differentiating T cells and include genes that spur leukemia/lymphoma translocations. Our results suggest the CAD targeting of translocation prone oncogenic genes is non-pathologic biology and aligns with initiation of cell fate transitions.

Facing increasing economization in the health care sector, clinicians have to adapt not only to the ever-growing economic challenges, but also to a patient-oriented health care. Treatment costs are the most important variable for optimizing success when facing scarce human resources, increasing material- and infrastructure costs in general, as well as low revenue flexibility due to flat rates per case in Germany, the so-called Diagnosis-Related Groups (DRG). University hospitals treat many patients with particularly serious illnesses. Therefore, their share of complex and expensive treatments, such as liver cirrhosis, is significantly higher. The resulting costs are not adequately reflected in the DRG flat rate per case, which is based on an average calculation across all hospitals, which increases this economic pressure. Thus, the aim of this manuscript is to review cost and revenue structures of the management of varices in patients with cirrhosis at a university center with a focus on hepatology. For this monocentric study, the data of 851 patients, treated at the Gastroenterology Department of a University Hospital between 2016 and 2020, were evaluated retrospectively and anonymously. Medical services (e.g., endoscopy, radiology, laboratory diagnostics) were analyzed within the framework of activity-based-costing. As part of the cost unit accounting, the individual steps of the treatment pathways of the 851 patients were monetarily evaluated with corresponding applicable service catalogs and compared with the revenue shares of the cost center and cost element matrix of the German (G-) DRG system. This study examines whether university-based high-performance medicine is efficient and cost-covering within the framework of the G-DRG system. We demonstrate a dramatic underfunding of the management of varicose veins in cirrhosis in our university center. It is therefore generally questionable whether and to what extent an adequate care for this patient collective is reflected in the G-DRG system., (Copyright © 2024. Published by Elsevier GmbH.)

The fate of selected UV filters (UVFs) was investigated in two soil aquifer treatment (SAT) systems, one supplemented with a reactive barrier containing clay and vegetable compost and the other as a traditional SAT reference system. We monitored benzophenone-3 (BP-3) and its transformation products (TPs), including benzophenone-1 (BP-1), 4,4'-dihydroxybenzophenone (4DHB), 4-hydroxybenzophenone (4HB), and 2,2'-dihydroxy-4-methoxybenzophenone (DHMB), along with benzophenone-4 (BP-4) and avobenzone (AVO) in all involved compartments (water, aquifer sediments, and biofilm). The reactive barrier, which enhances biochemical activity and biofilm development, improved the removal of all detected UVFs in water samples. Among monitored UVFs, only 4HB, BP-4, and AVO were detected in sediment and biofilm samples. But the overall retained amounts were several orders of magnitude larger than those dissolved. These amounts were quantitatively reproduced with a specifically developed simple analytical model that consists of a mobile compartment and an immobile compartment. Retention and degradation are restricted to the immobile water compartment, where biofilm absorption was simulated with well-known compound-specific K ow values. The fact that the model reproduced observations, including metabolites detected in the biofilm but not in the (mobile) water samples, supports its validity. The results imply that accumulation ensures significant biodegradation even if the degradation rates are very low and suggest that our experimental findings for UVFs and TPs can be extended to other hydrophobic compounds. Biofilms act as accumulators and biodegraders of hydrophobic compounds.