Dual Nucleosomal Double-Strand Breaks Are the Key Effectors of Curative Radiation Therapy

Most ionizing radiation produces δ-rays of ≈1 keV that can impart MGy doses to 100 nm3 volumes of DNA. These events can produce severe dual double-strand breaks (DDSBs) on nucleosomes, particularly in dense heterochromatic DNA. This is the most common multiply damaged site, and their probabilities determine the biological effectiveness of different types of radiation. We discuss their frequency, effect on cell survival, DNA repair, and imaging by gold nanoparticle tracers and electron microscopy. This new and valuable nanometer resolution information can be used for determining the optimal tumor cure by maximizing therapeutic effects on tumors and minimizing therapeutic effects on normal tissues. The production of DDSBs makes it important to deliver a rather high dose and LET to the tumor (>2.5 Gy/Fr) and at the same time reach approximately 1.8–2.3 Gy of the lowest possible LET per fraction in TP53 intact normal tissues at risk. Therefore, their intrinsic low-dose hyper-sensitivity (LDHS)-related optimal daily fractionation window is utilized. Before full p53 activation of NHEJ and HR repair at ≈½ Gy, the low-dose apoptosis (LDA) and LDHS minimize normal tissue mutation probabilities. Ion therapy should thus ideally produce the lowest possible LET in normal tissues to avoid elevated DDSBs. Helium to boron ions can achieve this with higher-LET Bragg peaks, producing increased tumor DDSB densities. Interestingly, the highest probability of complication-free cure with boron or heavier ions requires a low LET round-up for the last 10–15 GyE, thereby steepening the dose response and further minimizing normal tissue damage. In conclusion, the new high-resolution DSB and DDSB diagnostic methods, and the new more accurate DNA-repair-based radiation biology, have been combined to increase our understanding of what is clinically important in curative radiation therapy. In fact, we must understand that we already passed the region of optimal LET and need to go back one step rather than forward, with oxygen being contemplated. As seen by the high overkill and severely high LET in the distal tumor and the increased LET to normal tissues (reminding of neutrons or neon ions), it is therefore preferable to use lithium–boron ions or combine carbon with an optimal 10–15 GyE photon, electron, or perhaps even a proton round-up, thus allowing optimized, fractionated, curative, almost complication-free treatments with photons, electrons, and light ions, introducing a real paradigm shift in curative radiation therapy with a potential 5 GyE tumor boost, 25% increase in complication-free cure and apoptotic–senescent Bragg Peak molecular light ion radiation therapy

miR-145 suppress the androgen receptor in prostate cancer cells and correlates to prostate cancer prognosis.

Androgen signalling through the androgen receptor (AR) is essential for prostate cancer initiation, progression and transformation to the lethal castration-resistant state. The aim of this study was to characterize the mechanisms by which miR-145 deregulation contribute to prostate cancer progression. The miR-145 levels, measured by quantitative reverse transcription-polymerase chain reaction, were found to inversely correlate with occurrence of metastases, survival and androgen deprivation therapy response in a well-characterized prostate cancer cohort. Introduction of ectopic miR-145 in prostate cancer cells generated an inhibitory effect on the AR at both transcript and protein levels as well as its activity and downstream targets prostate-specific antigen (PSA), kallikrein-related peptidase 2 and TMPRSS2. The regulation was shown to be mediated by direct binding using Ago2-specific immunoprecipitation, but there was also indication of synergetic AR activation. These findings were verified in clinical prostate specimens by demonstrating inverse correlations between miR-145 and AR expression as well as serum PSA levels. In addition, miR-145 was found to regulate androgen-dependent cell growth in vitro. Our findings put forward novel possibilities of therapeutic intervention, as miR-145 potentially could decrease both the stem cells and the AR expressing bulk of the tumour and hence reduce the transformation to the deadly castration-resistant form of prostate cancer

Longitudinal Effects of the Family Support Program Chancenreich on Parental Involvement and the Language Skills of Preschool Children

When they enter primary school children already vary significantly in their language skills, depending at least in part on their family’s social background. In particular, the home learning environment plays a significant role in children’s development. For that reason, early intervention programs have been developed to obviate learning difficulties and to promote health, children’s development, and educational equality. The family support program Chancenreich aims to encourage the interaction and relationship between parents and children through two different course formats. The present study examines the longitudinal effects of attending the Chancenreich program and different course formats on (a) parents attending further educational services for children after completing the program, (b) children’s vocabulary and level of grammar development at the age of 5 and (c) the children’s vocabulary development between the ages of 3 and 5. Furthermore, we examine the relationship between family characteristics and the attendance rates of different course formats of the Chancenreich program at the first and second point of measurement. The study follows a longitudinal design with two points of measurements (T1: Mage = 41 months, T2: Mage = 68 months), and a sample size of 121 parents and their children at T2 in the intervention group and 41 parents and their children in the comparison group. Findings indicate that attendance of the Chancenreich program’s courses is related to child and family characteristics and to later patterns of course participation after completing the program. Further, both children’s level of vocabulary skills (PPVT) at the age of 5 and their development between the ages of 3 and 5 benefit from the parental participation in parenting skills training at the age of 3. Implications and future research on the effectiveness of family support programs are discussed

The importance of migration-related beliefs of preschool teachers for the quality of educational practice

Migrationsbezogene Überzeugungen von frühpädagogischen Fachkräften werden insbesondere in kulturell diversen Kindertageseinrichtungen eine handlungsleitende Bedeutung zugesprochen, obwohl es für diese Annahme kaum empirische Belege gibt. Die vorliegende Studie setzt hier an und untersucht, ob die migrationsbezogenen Überzeugungen von N = 206 frühpädagogischen Fachkräften im Zusammenhang mit der in ihren N = 107 Kindertageseinrichtungen beobachteten sprachspezifischen Prozess- und Strukturqualität stehen. Als migrationsbezogene Überzeugungsfacetten wurden die multikulturellen und assmiliativen Überzeugungen berücksichtigt, die anhand von Selbsteinschätzungen erfragt wurden. Die sprachspezifische Prozess- und Strukturqualität wurde mithilfe verschiedener Subskalen der Skala zum Sustained Shared Thinking und zum emotionalen Wohlbefinden (SSTEW), der Kindergarten-Skala-Erweiterung (KES-E) sowie einer selbst entwickelten Skala „Sprach- und kultursensible Raumgestaltung“ (SKR) in Beobachtungen eingeschätzt. Die multikulturellen und assimilativen Überzeugungen der frühpädagogischen Fachkräfte gingen neben ausgewählten Struktur- und Fachkraftmerkmalen getrennt in Strukturgleichungsmodelle ein. Die Ergebnisse zeigten, dass die multikulturellen Überzeugungen der frühpädagogischen Fachkräfte signifikant positiv mit der Subskala „Sprache“ der KES‑E und der Skala „Sprach- und kultursensible Raumgestaltung“ zusammenhingen. Die assimilativen Überzeugungen waren hingegen mit keiner der drei sprachspezifischen Qualitätsmaße assoziiert.Especially in culturally diverse preschools, migration-related beliefs of preschool teachers are assigned a major importance for pedagogical practice, although so far there has been hardly any research on this relation. The present study explored whether the migration-related beliefs of 206 preschool teachers are related to the language-related process and structural quality observed in their 107 preschools. As facets of migration-related belief, the multicultural and assimilative beliefs based on self-assessments were taken into account. The language-related process and structural quality was rated on the basis of the subscale “Supporting and extending language and communication” of the Sustained Shared Thinking and Emotional Well-being Scale (SSTEW), the subscale “Literacy” of the Early Childhood Rating Scale-Revised (ECERS-R) as well as the scale “Language and Cultural Sensitive Room Formation” (SKR). The multicultural and assimilative beliefs of the preschool teachers were included separately alongside selected structural and teacher characteristics in structural equation models. The results showed that the multicultural beliefs of the preschool teachers were significantly positively related to the subscale “Literacy” of the ECERS‑R and the scale “Language and Cultural Sensitive Room Formation”. In contrast, the assimilative beliefs were not associated with any of the three language-related quality measures

Environmental impacts of high penetration renewable energy scenarios for Europe

The prospect of irreversible environmental alterations and an increasingly volatile climate pressurises societies to reduce greenhouse gas emissions, thereby mitigating climate change impacts. As global electricity demand continues to grow, particularly if considering a future with increased electrification of heat and transport sectors, the imperative to decarbonise our electricity supply becomes more urgent. This letter implements outputs of a detailed power system optimisation model into a prospective life cycle analysis framework in order to present a life cycle analysis of 44 electricity scenarios for Europe in 2050, including analyses of systems based largely on low-carbon fossil energy options (natural gas, and coal with carbon capture and storage (CCS)) as well as systems with high shares of variable renewable energy (VRE) (wind and solar). VRE curtailments and impacts caused by extra energy storage and transmission capabilities necessary in systems based on VRE are taken into account. The results show that systems based largely on VRE perform much better regarding climate change and other impact categories than the investigated systems based on fossil fuels. The climate change impacts from Europe for the year 2050 in a scenario using primarily natural gas are 1400 Tg CO2-eq while in a scenario using mostly coal with CCS the impacts are 480 TgCO2-eq. Systems based on renewables with an even mix of wind and solar capacity generate impacts of 120–140 TgCO2-eq. Impacts arising as a result of wind and solar variability do not significantly compromise the climate benefits of utilising these energy resources. VRE systems require more infrastructure leading to much larger mineral resource depletion impacts than fossil fuel systems, and greater land occupation impacts than systems based on natural gas. Emissions and resource requirements from wind power are smaller than from solar power

A CRISPR Interference Screen of Essential Genes Reveals that Proteasome Regulation Dictates Acetic Acid Tolerance in Saccharomyces cerevisiae

CRISPR interference (CRISPRi) is a powerful tool to study cellular physiology under different growth conditions, and this technology provides a means for screening changed expression of essential genes. In this study, a Saccharomyces cerevisiae CRISPRi library was screened for growth in medium supplemented with acetic acid. Acetic acid is a growth inhibitor challenging the use of yeast for the industrial conversion of lignocellulosic biomasses. Tolerance to acetic acid that is released during biomass hydrolysis is crucial for cell factories to be used in biorefineries. The CRISPRi library screened consists of .9,000 strains, where .98% of all essential and respiratory growth-essential genes were targeted with multiple guide RNAs (gRNAs). The screen was performed using the high-throughput, high-resolution Scan-o-matic platform, where each strain is analyzed separately. Our study identified that CRISPRi targeting of genes involved in vesicle formation or organelle transport processes led to severe growth inhibition during acetic acid stress, emphasizing the importance of these intracellular membrane structures in maintaining cell vitality. In contrast, strains in which genes encoding subunits of the 19S regulatory particle of the 26S proteasome were downregulated had increased tolerance to acetic acid, which we hypothesize is due to ATP salvage through an increased abundance of the 20S core particle that performs ATP-independent protein degradation. This is the first study where high-resolution CRISPRi library screening paves the way to understanding and bioengineering the robustness of yeast against acetic acid stress

CRISPRi screen highlights chromatin regulation to be involved in formic acid tolerance in Saccharomyces cerevisiae

Formic acid is one of the main weak acids in lignocellulosic hydrolysates that is known to be inhibitory to yeast growth even at low concentrations. In this study, we employed a CRISPR interference (CRISPRi) strain library comprising >9000 strains encompassing >98% of all essential and respiratory growth-essential genes, to study formic acid tolerance in Saccharomyces cerevisiae. To provide quantitative growth estimates on formic acid tolerance, the strains were screened individually on solid medium supplemented with 140 mM formic acid using the Scan-o-Matic platform. Selected resistant and sensitive strains were characterized in liquid medium supplemented with formic acid and in synthetic hydrolysate medium containing a combination of inhibitors. Strains with gRNAs targeting genes associated with chromatin remodeling were significantly enriched for strains showing formic acid tolerance. In line with earlier findings on acetic acid tolerance, we found genes encoding proteins involved in intracellular vesicle transport enriched among formic acid sensitive strains. The growth of the strains in synthetic hydrolysate medium followed the same trend as when screened in medium supplemented with formic acid. Strains sensitive to formic acid had decreased growth in the synthetic hydrolysate and all strains that had improved growth in the presence of formic acid also grew better in the hydrolysate medium. Systematic analysis of CRISPRi strains allowed identification of genes involved in tolerance mechanisms and provided novel engineering targets for bioengineering strains with increased resistance to inhibitors in lignocellulosic hydrolysates

Evidence for DNA-mediated nuclear compartmentalization distinct from phase separation.

RNA Polymerase II (Pol II) and transcription factors form concentrated hubs in cells via multivalent protein-protein interactions, often mediated by proteins with intrinsically disordered regions. During Herpes Simplex Virus infection, viral replication compartments (RCs) efficiently enrich host Pol II into membraneless domains, reminiscent of liquid-liquid phase separation. Despite sharing several properties with phase-separated condensates, we show that RCs operate via a distinct mechanism wherein unrestricted nonspecific protein-DNA interactions efficiently outcompete host chromatin, profoundly influencing the way DNA-binding proteins explore RCs. We find that the viral genome remains largely nucleosome-free, and this increase in accessibility allows Pol II and other DNA-binding proteins to repeatedly visit nearby DNA binding sites. This anisotropic behavior creates local accumulations of protein factors despite their unrestricted diffusion across RC boundaries. Our results reveal underappreciated consequences of nonspecific DNA binding in shaping gene activity, and suggest additional roles for chromatin in modulating nuclear function and organization