410 research outputs found

    Granulomatosis with polyangiitis mimicking infective endocarditis in an adolescent male

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    Granulomatosis with polyangiitis (GPA) is a rare but serious small vessel vasculitis with heterogeneous clinical presentation ranging from mainly localised disease with a chronic course, to a florid, acute small vessel vasculitic form characterised by severe pulmonary haemorrhage and/or rapidly progressive vasculitis or other severe systemic vasculitic manifestations. Cardiac involvement is, however, uncommon in the paediatric population. We report a case of a 16-year-old male who presented with peripheral gangrene and vegetation with unusual location on the supporting apparatus of the tricuspid valve, initially considered to have infective endocarditis but ultimately diagnosed with GPA. We provide an overview of the limited literature relating to cardiac involvement in GPA, and the diagnostic challenge relating to infective endocarditis in this context, especially focusing on the interpretation of the antineutrophil cytoplasmic antibody (ANCA) and the characteristic clinical features to identify in order to promptly recognise GPA, since timely diagnosis and treatment are essential for this potentially life-threatening condition

    Micro-CT yields high image quality in human fetal post-mortem imaging despite maceration

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    Background Current clinical post-mortem imaging techniques do not provide sufficiently high-resolution imaging for smaller fetuses after pregnancy loss. Post-mortem micro-CT is a non-invasive technique that can deliver high diagnostic accuracy for these smaller fetuses. The purpose of the study is to identify the main predictors of image quality for human fetal post-mortem micro-CT imaging. Methods Human fetuses were imaged using micro-CT following potassium tri-iodide tissue preparation, and axial head and chest views were assessed for image quality on a Likert scale by two blinded radiologists. Simple and multivariable linear regression models were performed with demographic details, iodination, tissue maceration score and imaging parameters as predictor variables. Results 258 fetuses were assessed, with median weight 41.7 g (2.6–350 g) and mean gestational age 16 weeks (11–24 weeks). A high image quality score (> 6.5) was achieved in 95% of micro-CT studies, higher for the head (median = 9) than chest (median = 8.5) imaging. The strongest negative predictors of image quality were increasing maceration and body weight (p < 0.001), with number of projections being the best positive imaging predictor. Conclusions High micro-CT image quality score is achievable following early pregnancy loss despite fetal maceration, particularly in smaller fetuses where conventional autopsy may be particularly challenging. These findings will help establish clinical micro-CT imaging services, addressing the need for less invasive fetal autopsy methods

    Ultrastructural features of neuroblastic tumours in relation to morphological, and molecular findings; a retrospective review study.

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    Neuroblastoma is the most common solid tumour of infancy and is responsible for 15% of childhood cancer deaths. Presence of amplified MYCN in neuroblastoma is associated with poor prognosis and rapid tumour progression. The aim of this study was to examine and compare the ultrastructural features of high-risk MYCN amplified neuroblastomas, with lower-risk non-MYCN amplified tumours

    Unsupervised phenotypic clustering for determining clinical status in children with cystic fibrosis

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    BACKGROUND: Cystic Fibrosis (CF) is a multisystem disease in which assessing disease severity based on lung function alone may not be appropriate. The aim of the study was to develop a comprehensive machine-learning algorithm to assess clinical status independent of lung function in children. METHODS: A comprehensive prospectively collected clinical database (Toronto, Canada) was used to apply unsupervised cluster analysis. The defined clusters were then compared by current and future lung function, risk of future hospitalisation, and risk of future pulmonary exacerbation (PEx) treated with oral antibiotics. A K-Nearest Neighbours (KNN) algorithm was used to prospectively assign clusters. The methods were validated in a paediatric clinical CF dataset from Great Ormond Street Hospital (GOSH). RESULTS: The optimal cluster model identified four (A-D) phenotypic clusters based on 12 200 encounters from 530 individuals. Two clusters (A,B) consistent with mild disease were identified with high FEV1, and low risk of both hospitalisation and PEx treated with oral antibiotics. Two clusters (C,D) consistent with severe disease were also identified with low FEV1. Cluster D had the shortest time to both hospitalisation and PEx treated with oral antibiotics. The outcomes were consistent in 3124 encounters from 171 children at GOSH. The KNN cluster allocation error rate was low, at 2.5% (Toronto), and 3.5% (GOSH). CONCLUSION: Machine learning derived phenotypic clusters can predict disease severity independent of lung function and could be used in conjunction with functional measures to predict future disease trajectories in CF patients

    Importance of Magnetic Resonance Imaging With Diffusion-weighted Imaging in Guiding Biopsy of Nodular Ganglioneuroblastoma: A Case Report

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    BACKGROUND: Nodular ganglioneuroblastoma is a rare peripheral neuroblastic tumor of variable prognosis. Accurate diagnosis, staging, and risk categorization can be particularly challenging in patients with nodular ganglioneuroblastoma due to the inherent heterogeneity of these lesions. CASE PRESENTATION: We illustrate the use of diffusion-weighted magnetic resonance imaging to identify tumor nodules and guide tumor biopsy in an almost 5-year-old boy with a large abdominal tumor. CONCLUSIONS: Diffusion-weighted magnetic resonance imaging was successful in detecting and guiding biopsy of a poorly differentiated neuroblastoma nodule within the context of a well-differentiated ganglioneuroma, allowing the diagnosis and characterization of a ganglioneuroblastoma nodular, thus influencing the child's prognosis and treatment

    In the beginning: Role of autonomy support on the motivation, mental health and intentions of participants entering an exercise referral scheme

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    Self-determination theory (Deci & Ryan, 2000, Intrinsic motivation and self-determination in human behaviour. New York: Plenum Publishing) highlights the impact autonomy supportive environments can have on exercise motivation and positive health outcomes. Yet little is known about whether differential effects occur as a function of which significant other is providing this support. Further, no research has examined the relationship between motivation and the social environment with participants’ mental health and intentions to be physically active before entering an exercise intervention. Study participants were 347 British adults who were about to start an exercise referral scheme. Regression analyses revealed that the effects of autonomy support on mental health and physical activity intentions differed as a function of who provided the support (offspring, partner or physician), with the offspring having the weakest effects. A structural model was supported, indicating that autonomy support and more autonomous regulations led to more positive mental health outcomes and stronger intentions to be physically active. Knowledge of the social environmental and personal motivation of those about to commence an exercise programme can provide important insights for professionals supporting such efforts

    The presence of Y674/Y675 phosphorylated NTRK1 via TP53 repression of PTPN6 expression as a potential prognostic marker in neuroblastoma

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    The tumor suppressor TP53 promotes nerve growth factor receptor (NTRK1) -Y674/Y675 phosphorylation (NTRK1-pY674/pY675) via repression of the NTRK1 phosphatase PTPN6 in a ligand-independent manner, resulting in suppression of breast cancer cell proliferation. Moreover, NTRK1-pY674/pY675 together with low levels of PTPN6 and TP53 expression is associated with favorable disease-free survival of breast cancer patients. We determined whether in neuroblastoma this protein expression pattern impacts relapse-free survival (RFS). NTRK1-pY674/pY675, PTPN6, and TP53 expression was assessed in 98 neuroblastoma samples by immunohistochemistry. Association between expression levels and RFS was investigated by multivariate and Kaplan-Meier analysis. Mutant or wild-type TP53 was identified by sequencing tumor DNA. Tumors expressing NTRK1-pY674/pY675 and low or undetectable levels of PTPN6 and TP53 were significantly associated with 5-year RFS (P = .014) when the dataset was stratified by MYCN amplification, segmental chromosomal abnormalities and histology. Similar results were observed with tumors expressing wild-type TP53, NTRK1-pY674/pY675 and low or undetectable levels of PTPN6. Kaplan-Meier analysis demonstrated a significant correlation (P = .004), with a 50% probability of RFS (median survival 4.73 years) when present compared with 19.51% (median survival 11.63 months) when absent. Similar results were seen with non-amplified MYCN or unfavorable/undifferentiating samples and tumors from patients aged 18 months or less. Importantly, NTRK1-pY674/pY675 is an independent predictor of improved RFS. These results strongly suggest that NTRK1-pY674/pY675 together with wild-type TP53 and undetectable or low levels of PTPN6 expression is a potential biomarker of improved RFS of neuroblastoma patients. The predictive value of NTRK1-pY674/pY675 together with wild-type TP53 and low PTPN6 expression could contribute to neuroblastoma patient prognosis

    Identification of bacterial pathogens in sudden unexpected death in infancy and childhood using 16S rRNA gene sequencing

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    Background Sudden unexpected death in infancy (SUDI) is the most common cause of post-neonatal death in the developed world. Following an extensive investigation, the cause of ~40% of deaths remains unknown. It is hypothesized that a proportion of deaths are due to an infection that remains undetected due to limitations in routine techniques. This study aimed to apply 16S rRNA gene sequencing to post-mortem (PM) tissues collected from cases of SUDI, as well as those from the childhood equivalent (collectively known as sudden unexpected death in infancy and childhood or SUDIC), to investigate whether this molecular approach could help identify potential infection-causing bacteria to enhance the diagnosis of infection. Methods In this study, 16S rRNA gene sequencing was applied to de-identified frozen post-mortem (PM) tissues from the diagnostic archive of Great Ormond Street Hospital. The cases were grouped depending on the cause of death: (i) explained non-infectious, (ii) infectious, and (iii) unknown. Results and conclusions In the cases of known bacterial infection, the likely causative pathogen was identified in 3/5 cases using bacterial culture at PM compared to 5/5 cases using 16S rRNA gene sequencing. Where a bacterial infection was identified at routine investigation, the same organism was identified by 16S rRNA gene sequencing. Using these findings, we defined criteria based on sequencing reads and alpha diversity to identify PM tissues with likely infection. Using these criteria, 4/20 (20%) cases of unexplained SUDIC were identified which may be due to bacterial infection that was previously undetected. This study demonstrates the potential feasibility and effectiveness of 16S rRNA gene sequencing in PM tissue investigation to improve the diagnosis of infection, potentially reducing the number of unexplained deaths and improving the understanding of the mechanisms involved
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