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Treatment options for Epstein-Barr virus (EBV)-cancers are limited, underscoring the need for new therapeutic approaches. We have previously shown that EBV-transformed cells and cancers lack homologous recombination (HR) repair, a prominent error-free pathway that repairs double-stranded DNA breaks; instead, EBV-transformed cells demonstrate genome-wide scars of the error-prone microhomology-mediated end joining (MMEJ) repair pathway. This suggests that EBV-cancers are vulnerable to synthetic lethal therapeutic approaches that target MMEJ repair. Indeed, we have previously found that targeting PARP, an enzyme that contributes to MMEJ, results in the death of EBV-lymphoma cells. With the emergence of clinical resistance to PARP inhibitors and the recent discovery of inhibitors of Polymerase theta (POLθ), the polymerase essential for MMEJ, we investigated the role of POLθ in EBV-lymphoma cells. We report that EBV-transformed cell lines, EBV-lymphoma cell lines, and EBV-lymphomas in AIDS patients demonstrate greater abundance of POLθ, driven by the EBV protein EBNA1, compared to EBV-uninfected primary lymphocytes and EBV-negative lymphomas from AIDS patients (a group that also abundantly expresses POLθ). We also find POLθ enriched at cellular DNA replication forks and exposure to the POLθ inhibitor Novobiocin impedes replication fork progress, impairs MMEJ-mediated repair of DNA double-stranded breaks, and kills EBV-lymphoma cells. Notably, cell killing is not due to Novobiocin-induced activation of the lytic/replicative phase of EBV. These findings support a role for POLθ not just in DNA repair but also DNA replication and as a therapeutic target in EBV-lymphomas and potentially other EBV-cancers as EBNA1 is expressed in all EBV-cancers. IMPORTANCE Epstein-Barr virus (EBV) contributes to ~2% of the global cancer burden. With a recent estimate of >200,000 deaths a year, identifying molecular vulnerabilities will be key to the management of these frequently aggressive and treatment-resistant cancers. Building on our earlier work demonstrating reliance of EBV-cancers on microhomology-mediated end-joining repair, we now report that EBV lymphomas and transformed B cell lines abundantly express the MMEJ enzyme POLθ that likely protects cellular replication forks and repairs replication-related cellular DNA breaks. Importantly also, we show that a newly identified POLθ inhibitor kills EBV-cancer cells, revealing a novel strategy to block DNA replication and repair of these aggressive cancers. [ABSTRACT FROM AUTHOR]

Mohammed F Rafey,1,2,* Conor F Murphy,1,2,* Razk Abdalgwad,1,2 Katriona Kilkelly,1 Helena Griffin,1 Niamh Beatty,1 Paula M O’Shea,3 Chris Collins,2,4 Robert McGrath,1 Mary Hynes,1 Colin Davenport,1,2 Martin O’Donnell,2 Francis M Finucane1,2 1Bariatric Medicine Service, Centre for Diabetes, Endocrinology and Metabolism, Galway University Hospitals, Galway, Ireland; 2HRB Clinical Research Facility, National University of Ireland, Galway, Ireland; 3Department of Clinical Biochemistry, Galway University Hospitals, Galway, Ireland; 4Department of Surgery, Galway University Hospitals, Galway, Ireland*These authors contributed equally to this workCorrespondence: Francis M FinucaneBariatric Medicine Service, Centre for Diabetes, Endocrinology and Metabolism, Galway University Hospital, Galway, IrelandTel +353 91 542711Email francis.finucane@hse.ieObjective: Low energy meal replacement regimens can induce short-term weight loss in patients with severe obesity, but usually require specially formulated dietary supplements. We sought to determine the effects of a milk-based meal replacement program on anthropometric and metabolic characteristics in adults with severe obesity.Methods: We conducted a retrospective cohort study of patients attending our hospital-based bariatric medicine service who completed a 24-week program consisting of eight weeks of milk-based meal replacement followed by weight stabilisation and maintenance phases. Patients were seen fortnightly by the bariatric physician, nurse and dietitian. We assessed changes in anthropometric and metabolic outcomes in completers at 0, 8, 16 and 24 weeks.Results: Of 105 program completers available for follow-up, 53.3% were female. Mean age was 51.1± 11.2 years. Body weight decreased from 144.0± 27.6 kg at baseline to 121.1± 25.0 kg at 24 weeks (P< 0.001), a mean total body weight loss of 15.9± 6.0%, with a reduction in body mass index from 50.6± 8.0 to 42.6± 7.6 kg m− 2 (P< 0.001). In patients with diabetes, haemoglobin A1c decreased from 66.3± 13.0 to 48.3± 13.5 mmol/mol (P< 0.001) and diabetes medication use decreased significantly. There were significant improvements also in lipid profiles and reductions in antihypertensive medication use.Conclusion: These preliminary findings suggest that completion of a 24-week milk-based meal replacement program has large effects on important outcomes in adults with severe obesity. However, attrition was high. Prospective assessment of the efficacy, safety, durability and cost-effectiveness of this intervention seems warranted.Keywords: hypocaloric diet, milk, lifestyle modification, obesity treatment, type 2 diabetes

Rationale: Routine spontaneous awakening and breathing trial coordination (SAT/SBT) improves outcomes for mechanically ventilated patients, but adherence varies. Understanding barriers to and facilitators of consistent daily use of SAT/SBT (implementation determinants) can guide the development of implementation strategies to increase adherence to these evidence-based interventions. Objectives: We conducted an explanatory, sequential mixedmethods study to measure variation in the routine daily use of SAT/SBT and to identify implementation determinants that might explain variation in SAT/SBT use across 15 intensive care units (ICUs) in urban and rural locations within an integrated, community-based health system. Methods: We described the patient population and measured adherence to daily use of coordinated SAT/SBT from January to June 2021, selecting four sites with varied adherence levels for semistructured field interviews. We conducted key informant interviews with critical care nurses, respiratory therapists, and physicians/advanced practice clinicians (n = 55) from these four sites between October and December 2021 and performed content analysis to identify implementation determinants of SAT/SBT use. Results: The 15 sites had 1,901 ICU admissions receiving invasive mechanical ventilation (IMV) for >24 hours during the measurement period. The mean IMV patient age was 58 years, and the median IMV duration was 5.3 days (interquartile range, 2.5-11.9). Coordinated SAT/SBT adherence (within 2 h) was estimated at 21% systemwide (site range, 9-68%). ICU clinicians were generally familiar with SAT/SBT but varied in their knowledge and beliefs about what constituted an evidence-based SAT/SBT. Clinicians reported that SAT/SBT coordination was difficult in the context of existing ICU workflows, and existing protocols did not explicitly define how coordination should be performed. The lack of an agreed-upon system-level measure for tracking daily use of SAT/SBT led to uncertainty regarding what constituted adherence. The effects of the COVID-19 pandemic increased clinician workloads, impacting performance. Conclusions: Coordinated SAT/SBT adherence varied substantially across 15 ICUs within an integrated, communitybased health system. Implementation strategies that address barriers identified by this study, including knowledge deficits, challenges regarding workflow coordination, and the lack of performance measurement, should be tested in future hybrid implementation-effectiveness trials to increase adherence to daily use of coordinated SAT/SBT and minimize harm related to the prolonged use of mechanical ventilation and sedation. [ABSTRACT FROM AUTHOR]

Shifting dietary protein intakes from animal to plant-based sources is suggested as a path to sustain the world's food consumption and maintain planetary resources (1). However, to facilitate change, it is important to characterise baseline dietary protein patterns. This study aimed to examine dietary protein intakes on the island of Ireland in order to determine population characteristics and food sources influencing protein intake. Analyses were performed on the Northern Ireland sub cohort of the UK National Dietary Nutrition Survey (NDNS 2016-2019) (2) and the Irish National Adult Nutrition Survey (2008-2010) (3). Both surveys used a four-day food diary and a final sample of 1484 adults, aged 18-64 years was extracted (NANS; n =1274 and NI NDNS; n=210). Mean daily intakes for protein (MDI; % total energy, TE) for the total population were calculated and the population was divided into three tertile groups based on low, medium and high protein intake (%TE). Differences in population characteristics, energy MDI, key nutrients (%TE or per 10MJ) and contributing food sources were examined across these tertiles, using chi-square and one-way ANOVA with covariates (age and BMI) and correcting for multiple comparisons as appropriate (P<0.005). Overall, 17.1% of TE was obtained from protein and 77% of participants met their protein DRV based on EFSA recommendations of 0.83g/kg/body weight (4). The difference in protein intakes between the highest and lowest tertiles was 7.8% TE (21.2 % TE vs 13.4% TE) with high protein consumers reporting lower energy intakes (1734 ± 564kcal) compared to low consumers (2185 ± 661 kcal). High protein consumers were older (42.5 ± 12.8 years) and had a higher BMI (27.7 ± 6.0 kg/m2). They also had higher MDI of dietary fibre, calcium, zinc, sodium, iron, folate and vitamins A, C, D and B12 (per 10MJ) (p<0.001) and lower MDI of carbohydrates, fat, saturated fat (%TE) in comparison to low consumers (p<0.001). The % contribution of 'chicken, turkey and dishes' (18.3%), 'beef, veal and dishes' (12.8%) and 'fish and fish products (7.0%) to protein intakes were significantly higher in the high versus the low consumption group (10%, 7.4%, 4.4% TE respectively; P<0.001). In contrast, those in the lowest protein intake group had a significantly higher intakes of protein coming from dietary sources including 'burgers, sausages and meat products (9.9 vs 5.9%), 'white bread and rolls' (6.9 vs 3.9%), 'potatoes (including chips)' (4.1 vs 2.9 %) and 'cakes, pastries, buns and fruit pies' (1.7 vs 0.8%) compared to high consumers. In general, animal protein sources contributed more to total daily protein intakes than plant sources, however, the pattern of protein foods differed according to level of protein intake. These findings will aid in the development of strategies to diversify protein intakes on the Island of Ireland. [ABSTRACT FROM AUTHOR]

A QTL that explained a large proportion of the phenotypic difference between broiler and layer chickens in an experimental cross was evaluated in a commercial broiler line. A three-generation design, consisting of 15 grandsires, 608 half-sib hens, and more than 50,000 third-generation offspring, was implemented within the existing breeding scheme of a broiler breeding company. Four markers from a candidate region on chicken chromosome 4 were selected for their informativeness in the grandsires and used to genotype the first two generations. Using half-sib analyses, linkage was studied between these markers and 13 growth and carcass traits. The QTL analyses confirmed the presence of significant QTL for body weight (P < 0.0]) and residual feed intake (P < 0.05) on chicken chromosome 4. Furthermore, evidence was found for QTL affecting the relative weight of bone and muscle in the thigh. Four more markers were added to increase resolution of the QTL positions. This increased the significance of the QTL for body weight (P < 0.001) and residual feed intake (P < 0.01) and showed evidence (P < 0.05) for additional QTL affecting carcass weight and conformation score. This study showed for the first time that a QTL that explains differences between broilers and layers was segregating in lines that have been selected for body weight over 50 generations. A possible explanation could be a pleiotropic or closely linked effect on fitness-related traits that are not part of the present study. The results demonstrate the feasibility of QTL detection and the potential for marker-assisted selection within a commercial broiler line without altering the existing breeding scheme. Key Words: Body Weight, Broilers, Genomes, Mapping, Poultry, Quantitative Trait Loci