In a comprehensive study to decipher the multi-layered response to the chemotherapeutic agent temozolomide (TMZ), we analyzed 427 genomes and determined mutational patterns in a collection of ∼40 isogenic DNA repair-deficient human TK6 lymphoblast cell lines. We first demonstrate that the spontaneous mutational background is very similar to the aging-associated mutational signature SBS40 and mainly caused by polymerase zeta-mediated translesion synthesis (TLS). MSH2-/- mismatch repair (MMR) knockout in conjunction with additional repair deficiencies uncovers cryptic mutational patterns.
View Article and Find Full Text PDFHuntington's disease (HD) arises from a CAG expansion in the () gene beyond a critical threshold. A major thrust of current HD therapeutic development is lowering levels of mutant mRNA (m) and protein (mHTT) with the aim of reducing the toxicity of these product(s). Human genetic data also support a key role for somatic instability (SI) in 's CAG repeat - whereby it lengthens with age in specific somatic cell types - as a key driver of age of motor dysfunction onset.
View Article and Find Full Text PDFBackground: The purpose of this study was to determine the clinical outcomes of mucous cystectomy and osteophytectomy using a random nonadvancement flap technique.
Methods: This was a therapeutic outcomes study of patients who underwent mucous cystectomy under local anesthesia by 1 of 2 hand fellowship-trained surgeons between 2012 and 2022. The key features of the surgical technique include designing a random nonadvancement flap with the cyst at its base; transecting the cyst pedicle as the flap is elevated; resecting the cyst wall from the undersurface of the reflected flap; decompressing the distal joint by removing marginal osteophytes; and insetting the flap without advancement.
Background: This study aimed to explore the disparities in PD-1 and PD-L1 expression among oral squamous cell carcinomas (OSCCs) in individuals categorized as never-smokers/never-drinkers versus smokers/drinkers.
Methods: Immunohistochemical staining for PD-1 and PD-L1, along with PDCD1LG2/cen9 dual color probe analysis, was conducted on 130 OSCC specimens from both smoker/drinker and never-smoker/never-drinker cohorts. Associations between smoking/drinking status, clinicopathologic data, immunohistochemical antibody expression, fluorescence in situ hybridization, and survival outcomes were assessed.
Front Cell Dev Biol
July 2024
Temozolomide (TMZ) is a methylating agent used as the first-line drug in the chemotherapy of glioblastomas. However, cancer cells eventually acquire resistance, necessitating the development of TMZ-potentiating therapy agents. TMZ induces several DNA base adducts, including -meG, 3-meA, and 7-meG.
View Article and Find Full Text PDFBackground: In recent years data-driven population segmentation using cluster analyses of mainly health care utilisation data has been used as a proxy of future health care need. Chronic conditions patterns tended to be examined after segmentation but may be useful as a segmentation variable which, in combination with utilisation could indicate severity. These could further be of practical use to target specific clinical groups including for prevention.
View Article and Find Full Text PDFTardigrades withstand ionizing irradiation levels ∼500 times higher than humans can tolerate. Two recent papers shed light on how this might be achieved - via the transcriptional induction of DNA repair genes, the induction of a radioprotective DNA-binding protein, and possibly also the heightened capacity of repair proteins.
View Article and Find Full Text PDFPhilos Trans A Math Phys Eng Sci
June 2024
The origin of micrometeorites (MMs) from asteroids and comets is well-established, but the relative contribution from these two classes remains poorly resolved. Likewise, determining the precise origin of individual MMs is an open challenge. Here, cosmic-ray exposure ages are used to resolve the spatial origins of 12 MMs collected from urban areas and Antarctica.
View Article and Find Full Text PDFHuman peptidylarginine deiminase isoform VI (PAD6), which is predominantly limited to cytoplasmic lattices in the mammalian oocytes in ovarian tissue, is essential for female fertility. It belongs to the peptidylarginine deiminase (PAD) enzyme family that catalyzes the conversion of arginine residues to citrulline in proteins. In contrast to other members of the family, recombinant PAD6 was previously found to be catalytically inactive.
View Article and Find Full Text PDFBackground: Secondary preventive outpatient diagnostic services for patients with pain and risk factors for chronification have not yet been sufficiently established. In the PAIN2020 project (Innovation Fund, 01NVF17049) an outpatient interdisciplinary multimodal assessment (IMA) was introduced for the first time early in the course of the disease.
Objective: For the implementation of the IMA procedures for team cooperation and decision criteria were developed, which were implemented by a team of medical, physiotherapeutic and psychological therapists.
The SMC5/6 complex is evolutionarily conserved across all eukaryotes and plays a pivotal role in preserving genomic stability. Mutations in genes encoding SMC5/6 complex subunits have been associated with human lung disease, immunodeficiency, and chromosome breakage syndrome. Despite its critical importance, much about the SMC5/6 complex remains to be elucidated.
View Article and Find Full Text PDFPolycyclic aromatic hydrocarbons (PAHs) are ubiquitous pollutants formed during the incomplete combustion of organic matter such as tobacco. Among these, benzo[a]pyrene (BaP) has been classified as a known carcinogen to humans. It unfolds its effect through metabolic activation to BaP-(7R,8S)-diol-(9S,10R)-epoxide (BPDE), the ultimate carcinogen of BaP.
View Article and Find Full Text PDFAccurate chromosome segregation during meiosis requires the establishment of at least one crossover (CO) between each pair of homologous chromosomes. CO formation depends on a group of conserved pro-CO proteins, which colocalize at CO-designated sites during late meiotic prophase I. However, it remains unclear whether these pro-CO proteins form a functional complex and how they promote meiotic CO formation in vivo.
View Article and Find Full Text PDFResearchers would be more willing to prioritize research quality over quantity if the incentive structure of the academic system aligned with this goal. The winner of a 2023 Einstein Foundation Award for Promoting Quality in Research explains how they rose to this challenge.
View Article and Find Full Text PDFBackground: Up to 27% of the German population suffers from recurrent or persistent pain (lasting more than three months). Therefore, prevention of chronic pain is one major object of pain management interventions. The aim of this nationwide, multicentre, randomised controlled trial is to evaluate the efficacy of a 10-week ambulatory (outpatient) interdisciplinary multimodal pain therapy (A-IMPT) for patients with recurrent pain and at risk of developing chronic pain.
View Article and Find Full Text PDFHistone chaperones control nucleosome density and chromatin structure. In yeast, the H3-H4 chaperone Spt2 controls histone deposition at active genes but its roles in metazoan chromatin structure and organismal physiology are not known. Here we identify the Caenorhabditis elegans ortholog of SPT2 (CeSPT-2) and show that its ability to bind histones H3-H4 is important for germline development and transgenerational epigenetic gene silencing, and that spt-2 null mutants display signatures of a global stress response.
View Article and Find Full Text PDFReproducible research and open science practices have the potential to accelerate scientific progress by allowing others to reuse research outputs, and by promoting rigorous research that is more likely to yield trustworthy results. However, these practices are uncommon in many fields, so there is a clear need for training that helps and encourages researchers to integrate reproducible research and open science practices into their daily work. Here, we outline eleven strategies for making training in these practices the norm at research institutions.
View Article and Find Full Text PDFHomologous recombination (HR) requires bidirectional end resection initiated by a nick formed close to a DNA double-strand break (DSB), dysregulation favoring error-prone DNA end-joining pathways. Here we investigate the role of the ATAD5, a PCNA unloading protein, in short-range end resection, long-range resection not being affected by ATAD5 deficiency. Rapid PCNA loading onto DNA at DSB sites depends on the RFC PCNA loader complex and MRE11-RAD50-NBS1 nuclease complexes bound to CtIP.
View Article and Find Full Text PDFIndividuals have a repertoire of emotion regulation (ER) strategies at their disposal, which they can use more or less flexibly. In ER flexibility research, strategies that facilitate goal achievement are considered adaptive and therefore are subjectively valuable. Individuals are motivated to reduce their emotional arousal effectively and to avoid cognitive effort.
View Article and Find Full Text PDFMelanoma antigen (MAGE) genes encode for a family of proteins that share a common MAGE homology domain. These genes are conserved in eukaryotes and have been linked to a variety of cellular and developmental processes including ubiquitination and oncogenesis in cancer. Current knowledge on the MAGE family of proteins mainly comes from the analysis of yeast and human cell lines, and their functions have not been reported at an organismal level in animals.
View Article and Find Full Text PDFHuman neuroscience has always been pushing the boundary of what is measurable. During the last decade, concerns about statistical power and replicability - in science in general, but also specifically in human neuroscience - have fueled an extensive debate. One important insight from this discourse is the need for larger samples, which naturally increases statistical power.
View Article and Find Full Text PDFRAD54 family DNA translocases partner with RAD51 recombinases to ensure stable genome inheritance, exhibiting biochemical activities both in promoting recombinase removal and in stabilizing recombinase association with DNA. Understanding how such disparate activities of RAD54 paralogs align with their biological roles is an ongoing challenge. Here we investigate the in vivo functions of Caenorhabditis elegans RAD54 paralogs RAD-54.
View Article and Find Full Text PDFThis combined experimental and theoretical study examines the influence of acene elongation, boron atom position, and acene substitution pattern on the structure and electronics of cyclic alkyl(amino)carbene (CAAC)-stabilized diboraacenes and presents the first syntheses of neutral diboranaphthalene (DBN) and diborapentacene (DBP). Whereas 2,3-diethyl-substituted 1,4-(CAAC)-DBN is isolated as a mixture of a planar (structurally characterized) NMR-active conformer and a presumably bent EPR-active conformer, 6,13-(CAAC)-DBP resembles 9,10-(CAAC)-DBA (DBA = diboraanthracene), with a highly puckered 6,13-DBP core and a typical biradical EPR signal. Both species are easily reduced to their puckered dianions.
View Article and Find Full Text PDFCells constantly accumulate mutations, which are caused by replication errors, as well as through the action of endogenous and exogenous DNA-damaging agents. Mutational patterns reflect the status of DNA repair machinery and the history of genotoxin exposure of a given cellular clone. Computationally derived mutational signatures can shed light on the origins of cancer.
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