Contribution of DNA repair and cell cycle checkpoint arrest to the maintenance of genomic stability

DNA damage response mechanisms encompass pathways of DNA repair, cell cycle checkpoint arrest and apoptosis. Together, these mechanisms function to maintain genomic stability in the face of exogenous and endogenous DNA damage. ATM is activated in response to double strand breaks and initiates cell cycle checkpoint arrest. Recent studies in human fibroblasts have shown that ATM also regulates a mechanism of end-processing that is required for a component of double strand break repair. Human fibroblasts rarely undergo apoptosis after ionising radiation and, therefore, apoptosis is not considered in our review. The dual function of ATM raises the question as to how the two processes, DNA repair and checkpoint arrest, interplay to maintain genomic stability. In this review, we consider the impact of ATM's repair and checkpoint functions to the maintenance of genomic stability following irradiation in G2. We discuss evidence that ATM's repair function plays little role in the maintenance of genomic stability following exposure to ionising radiation. ATM's checkpoint function has a bigger impact on genomic stability but strikingly the two damage response pathways co-operate in a more than additive manner. In contrast, ATM's repair function is important for survival post irradiation

Impact of a hypomorphic Artemis disease allele on lymphocyte development, DNA end processing, and genome stability

Artemis was initially discovered as the gene inactivated in human radiosensitive T−B− severe combined immunodeficiency, a syndrome characterized by the absence of B and T lymphocytes and cellular hypersensitivity to ionizing radiation. Hypomorphic Artemis alleles have also been identified in patients and are associated with combined immunodeficiencies of varying severity. We examine the molecular mechanisms underlying a syndrome of partial immunodeficiency caused by a hypomorphic Artemis allele using the mouse as a model system. This mutation, P70, leads to premature translation termination that deletes a large portion of a nonconserved C terminus. We find that homozygous Artemis-P70 mice exhibit reduced numbers of B and T lymphocytes, thereby recapitulating the patient phenotypes. The hypomorphic mutation results in impaired end processing during the lymphoid-specific DNA rearrangement known as V(D)J recombination, defective double-strand break repair, and increased chromosomal instability. Biochemical analyses reveal that the Artemis-P70 mutant protein interacts with the DNA-dependent protein kinase catalytic subunit and retains significant, albeit reduced, exo- and endonuclease activities but does not undergo phosphorylation. Together, our findings indicate that the Artemis C terminus has critical in vivo functions in ensuring efficient V(D)J rearrangements and maintaining genome integrity

Prevention and management of excessive gestational weight gain: a survey of overweight and obese pregnant women

Background - Excessive gestational weight gain is associated with adverse infant, childhood and maternal outcomes and research to develop interventions to address this issue is ongoing. The views of women on gestational weight gain and the resources they would consider helpful in addressing this are however largely unknown. This survey aimed to determine the views of newly pregnant women, living in areas of social disadvantage, on 1) their current body weight and potential gestational weight gain and 2) the resources or interventions they would consider helpful in preventing excessive gestational weight gain. Methods - A convenience sample of overweight and obese pregnant women living in Fife, UK, were invited to complete a short anonymised questionnaire at their 12 week booking visit. Results - 428 women, BMI>25 kg/m2, completed the questionnaire. Fifty-four per cent of respondents were obese (231) and 62% were living in areas of mild to moderate deprivation. Over three-quarters of participants felt dissatisfied with their current weight (81%). The majority of women (60%) expressed some concern about potential weight gain. Thirty-nine percent were unconcerned about weight gain during their pregnancy, including 34 women (19%) who reported having retained weight gained in earlier pregnancies. Amongst those concerned about weight gain advice on physical activity (41%) and access to sports/leisure facilities were favoured resources (36%). Fewer women (12%) felt that group sessions on healthy eating or attending a clinic for individualised advice (14%) would be helpful. "Getting time off work" was the most frequently cited barrier (48%) to uptake of resources other than leaflets. Conclusions- These data suggest a lack of awareness amongst overweight and obese women regarding excessive gestational weight gain. Monitoring of gestational weight gain, and approaches for its management, should be formally integrated into routine antenatal care. Barriers to the uptake of resources to address weight gain are numerous and must be considered in the design of future interventions and services

An empirical approach to assessing pediatric residents\u27 attitudes, knowledge, and skills in primary care behavioral health

This paper describes an empirical approach to assessing pediatric residents\u27 attitudes, knowledge and skills in primary care behavioral health. Outcomes from that assessment approach are presented from two pediatric residency training programs in the northeastern United States. Thirty-six pediatric residents completed attitudes, knowledge and skills surveys. The survey was developed to align with the American Academy of Pediatrics’ Policy Statement in 2009 citing aspirational competencies for pediatricians in primary care behavioral health. This alignment addressed both learner variables (attitudes, knowledge, and skills) as well as clinical presentations (ADHD, anxiety, depression, and suicide) highlighted in the policy statement. The survey specifically inquired about self-reported confidence and comfort in managing behavioral health concerns using evidence-based practice parameters (attitudes and knowledge) and their measured ability to deliver evidence-based care in response to clinical vignettes (skills). Findings largely revealed no statistically significant differences in attitudes, knowledge or skills between interns and upper-level residents. Training programs can use the approach described in this paper and the assessment instrument with some possible modifications to monitor annual progress and evaluate any changes in didactic and clinical training

Adapting and developing an academic and community practice collaborative care model for metastatic breast cancer care (Project ADAPT): Protocol for an implementation science-based study

BACKGROUND: Metastatic breast cancer (MBC) remains incurable despite significant treatment advances. Coordinating care for patients with MBC can be challenging given the various treatment options, available clinical trials, and frequent need for ancillary services. To optimize MBC care, we designed a project for adapting and developing an academic and community practice collaborative care model for MBC care (Project ADAPT), based on the Ending Metastatic Breast Cancer for Everyone (EMBRACE) program developed at Dana Farber Cancer Institute. OBJECTIVE: We aim to describe the implementation science-based study design and innovative components of Project ADAPT. METHODS: Project ADAPT uses the Dynamic Adaptation Process informed by the Exploration, Preparation, Implementation, Sustainment framework. Washington University School of Medicine (WUSM) partnered with 3 community hospitals in the St. Louis region covering rural and urban settings. The exploration and preparation phases provide patient and provider feedback on current referral practices to finalize the approach for the implementation phase. At the implementation phase, we will enroll patients with MBC at these 3 community sites to evaluate potential collaborative care at WUSM and assess the impact of this collaborative care model on referral satisfaction and acceptability for patients with MBC and their providers. Patients may then return to their community site for care or continue to receive part of their care at WUSM. We are incorporating virtual and digital health strategies to improve MBC care coordination in order to minimize patient burden. RESULTS: The exploration phase is ongoing. As of August 2021, we have recruited 21 patient and provider participants to complete surveys of the current collaborative care process at WUSM. Using a 2-tailed paired t test, 44 patients (including 10 patients from the exploration phase) and 32 oncologists are required to detect an effect size of 0.5 with 80% power at a level of significance of .05. Throughout this phase and in preparation for the implementation phase, we have iteratively updated and refined our surveys for the implementation phase based on testing of our data collection instruments. Our partner sites are in various stages of the single institutional review board (IRB) approval process. We have ongoing engagement with all partner sites, which has helped solidify our participant recruitment strategies and design patient-friendly recruitment materials. In addition, we have included a patient advocate on the research team. Members of the research team have launched a single IRB Support Network at WUSM to create a repository of the single IRB procedures in order to streamline the partner site onboarding process and facilitate enhanced collaboration across institutions. CONCLUSIONS: With this robust model, we expect that patients with MBC will receive optimal care regardless of geographical location and the model will improve patient and provider experiences when navigating the health system. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/35736

Right cranial lung lobe torsion after a diaphragmatic rupture repair in a Jack Russell terrier

A seven-year-old male Jack Russell terrier was presented with a history of coughing, generalised weakness and lethargy 10 days after an abdominal coeliotomy to repair a large diaphragmatic rupture. Thoracic radiographs demonstrated a soft tissue mass in the midcaudal right thoracic cavity. Ultrasonographic studies, bronchoscopy and subsequent exploratory thoracotomy confirmed a diagnosis of a right cranial lung lobe torsion (LLT), with an anomalous caudodorsal displacement of the affected lobe. LLT should be considered as a differential diagnosis for respiratory tract disease following diaphragmatic rupture repair

Sacrocolpopexy without concomitant posterior repair improves posterior compartment defects

The aim of this study is to determine posterior compartment topography 1-year after sacrocolpopexy (SC). Women who had SC without concomitant anterior or posterior repairs for symptomatic pelvic organ prolapse (POP) were included. Vaginal topography was assessed at baseline and 1-year postoperatively using POP quantification (POPQ). At baseline, 24% had stage IV POP, 68% stage III, and 8% stage II. One year after surgery, 75% had stage 0/I POP, 24% stage II, and 1% stage III. 112 (75%) were objectively cured (stage 0 or I POP). Anterior compartment was the most common site of POP persistence or recurrence (Ba ≥ stage II in 23 women) followed by posterior compartment (Bp ≥ stage II in 12 women) and apex (C ≥ stage II in 2 women). In 1-year follow-up, SC without concomitant posterior repair restores posterior vaginal topography in the majority of women with undergoing SC