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Cardiac malformations (CVMs) are a leading cause of infant morbidity and mortality. CVMs are particularly prevalent when the developing fetus is exposed to high levels of phenylalanine in-utero in mothers with Phenylketonuria. Yet, elucidating the underlying molecular mechanism leading to CVMs has proven difficult. In this study we used RNA-Seq to investigate an avian model of MPKU and establish differential gene expression (DEG) characteristics of the early developmental stages HH10, 12, and 14. In total, we identified 633 significantly differentially expressed genes across stages HH10, 12, and 14. As expected, functional annotation of significant DEGs identified associations seen in clinical phenotypes of MPKU including CVMs, congenital heart defects, craniofacial anomalies, central nervous system defects, and growth anomalies. Additionally, there was an overrepresentation of genes involved in cardiac muscle contraction, adrenergic signaling in cardiomyocytes, migration, proliferation, metabolism, and cell survival. Strikingly, we identified significant changes in expression with multiple genes involved in Retinoic Acid (RA) metabolism and downstream targets. Using qRTPCR, we validated these findings and identified a total of 42 genes within the RA pathway that are differentially expressed. Here, we report the first elucidation of the molecular mechanisms of cardiovascular malformations in MPKU conducted at early developmental timepoints. We provide evidence suggesting a link between PHE exposure and the alteration of RA pathway. These results are promising and offer novel findings associated with congenital heart defects in MPKU. 相似文献
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Bronwyn Louise Pearse Claire M. Rickard Samantha Keogh Yoke Lin Fung 《Australian critical care》2019,32(2):92-99
Background
Bleeding management in cardiac surgery is challenging. Many guidelines exist to support bleeding management; however, literature demonstrates wide variation in practice. In 2012, a quality initiative was undertaken at The Prince Charles Hospital, Australia to improve bleeding management for cardiac surgery patients. The implementation of the quality initiative resulted in significant reductions in the incidence of blood transfusion, re-exploration for bleeding; superficial leg and chest wound infections; length of hospital stay, and cost. Given the success of the initiative, we sought to answer the question; “How and why was the process of implementing a bleeding management quality initiative in the cardiac surgery unit successful, and sustainable?”Methods
A retrospective explanatory case study design was chosen to explore the quality initiative. Analysis of the evidence was reviewed through phases of the ‘Knowledgeto Action’ planned change model. Data was derived from: (1) document analysis, (2) direct observation of the local environment, (3) clinical narratives from interviews, and analysed with a triangulation approach. The study period extended from 10/2011 to 6/2013.Results
Results demonstrated the complexity of changing practice, as well as the significant amount of dedicated time and effort required to support individual, department and system wide change. Results suggest that while many clinicians were aware of the potential to apply improved practice, numerous barriers and challenges needed to be overcome to implement change across multiple disciplines and departments.Conclusions
The key successful components of the QI were revealed through the case study analysis as: (1) an appropriately skilled project manager to facilitate the implementation process; (2) tools to support changes in workflow and decision making including a bleeding management treatment algorithm with POCCTs; (3) strong clinical leadership from the multidisciplinary team and; (4) the evolution of the project manager position into a perpetual clinical position to support sustainability. 相似文献7.
Jason Saliba Nikki A. Evensen Julia A. Meyer Daniel Newman Jacob Nersting Sonali Narang Xiaotu Ma Kjeld Schmiegelow William L. Carroll 《Pediatric blood & cancer》2020,67(7)
Relapse‐enriched somatic variants drive drug resistance in childhood acute lymphoblastic leukemia. We used digital droplet‐based polymerase chain reaction to establish whether relapse‐enriched mutations in emerging subclones could be detected in peripheral blood samples before frank relapse. Although limitations in sensitivity for some probes hindered detection of certain variants, we successfully detected variants in NT5C2 and PRPS1 at a fractional abundance of 0.005% to 0.3%, 41 to 116 days before relapse. As mutations in both these genes confer resistance to thiopurines, early detection protocols using peripheral blood could be implemented to preemptively alter maintenance therapy to extinguish resistant clones before overt relapse. 相似文献
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Suzanne Rainsford Nikki Johnston Wai-Man Liu Nicholas Glasgow Liz Forbat 《Progress in Palliative Care》2020,28(5):308-317
New approaches are needed to assist residential aged care (RAC) staff increase their skills and confidence in identifying when residents are nearing the dying phase and managing symptoms. One new evidence-based approach to improve palliative and end-of-life care in RAC is outreach Specialist Palliative Care Needs Rounds (monthly triage and risk stratification meetings – hereafter Needs Rounds); as yet untried in rural settings which may face unique enablers or challenges. Needs Rounds were introduced into two RAC facilities in the rural Snowy Monaro region of New South Wales, Australia. This study explored staff and general practitioners’(GPs’) experiences and perceptions of palliative and end-of-life care in rural RAC, and staff confidence and capability in providing such care, prior to, and after the introduction of Needs Rounds. A mixed-methods, pre- and post-intervention approach was taken, utilizing a Likert-scale written questionnaire and face-to-face semi-structured interviews. Between March and November 2018, 61 questionnaires were completed by 48 RAC staff (33 pre-, 28 post-intervention); eight staff and three GPs were interviewed. Despite system and site-specific barriers, staff self-reported that Needs Rounds increased their capability in providing end-of-life care (p?=?0.04; 95% CI 0.20–7.66), and improved staff: (1) awareness of end of life, reflective practice, and critical thinking; (2) end-of-life decision making and planning; and (3) pain management. Needs Rounds are acceptable and feasible in rural RAC. Palliative and end-of-life care for residents may be improved through education, collaboration, communication, and planning. Further studies should explore running Needs Rounds via telehealth and/or utilizing a multidisciplinary approach. 相似文献
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Nikki H. Stricker Jenna E. Keller Diane T. Castillo Kathleen Y. Haaland 《Journal of traumatic stress》2015,28(2):102-109
Neurocognitive problems are common with posttraumatic stress disorder (PTSD) and are important to understand because of their association with the success of PTSD treatment and its potential neural correlates. To our knowledge, this is the first neurocognitive study in an all‐female U.S. veteran sample, some of whom had PTSD. We examined neurocognitive performance and assessed whether learning deficits, common in PTSD, were associated with executive functioning. Veterans with PTSD (n = 56) and without (n = 53) were evaluated for psychiatric and neurocognitive status. The PTSD group had a lower estimated IQ (d = 0.53) and performed more poorly on all neurocognitive domains (d range = 0.57–0.88), except verbal retention (d = 0.04). A subset of the 2 groups that were matched on IQ and demographics similarly demonstrated poorer performance for the PTSD group on all neurocognitive domains (d range = 0.52–0.79), except verbal retention (d = 0.15). Within the PTSD group, executive functioning accounted for significant variance in verbal learning over and above IQ and processing speed (ΔR2 = .06), as well as depression (ΔR2 = .07) and PTSD severity (ΔR2 = .06). This study demonstrated that female veterans with PTSD performed more poorly than females without PTSD on several neurocognitive domains, including verbal learning, processing speed, and executive functioning. Replication of these results using a control group of veterans with more similar trauma exposure, history of mild traumatic brain injury, and psychiatric comorbidities would solidify these findings. 相似文献