All Publications

  • Multi-disciplinary evaluation of a 5-month-old with hypertrophic cardiomyopathy related to a functional adrenocortical tumor. Journal of pediatric endocrinology & metabolism : JPEM Nally, L. M., Conner, E., Paige, S., Mooney, K. L., Naber, U., Richards, R., Wright, G. 2018


    Background Hypertrophic cardiomyopathy (HCM) in childhood is a rare diagnosis, and associations with adrenocortical tumors (ACTs) have been rarely reported in the pediatric literature. Case Presentation We present a case of a 5-month-old who presented with HCM and during the evaluation for hypertension was found to have elevated glucocorticoids, mineralocorticoids, androgens and urine metanephrines. During preoperative evaluation, he developed shock followed by cardiogenic collapse requiring extracorporeal membrane oxygenation (ECMO); however, he did not survive. Pathology revealed an ACT with hormone production that contributed to his demise. Conclusion Adrenocortical tumors associated with hypertrophic cardiomyopathy can be life-threatening. We discuss the complex interplay of unrestricted cortical hormone production in the setting of hypertrophic cardiomyopathy that may lead to rapid decline and poor clinical outcomes.

    View details for DOI 10.1515/jpem-2018-0340

    View details for PubMedID 30352041

  • Rolling-refresher simulation improves performance and retention of paediatric intensive care unit nurse code cart management BMJ SIMULATION & TECHNOLOGY ENHANCED LEARNING Singleton, M. N., Allen, K. F., Li, Z., McNerney, K., Naber, U. H., Braga, M. S. 2018; 4 (2): 77–82


    Paediatric Intensive Care Unit Nurses (PICU RNs) manage the code cart during paediatric emergencies at the Children's Hospital at Dartmouth-Hitchcock. These are low -frequency, high-stakes events.An uncontrolled intervention study with 6-month follow-up. A collaboration of physician and nursing experts developed a rolling-refresher training programme consisting of five simulated scenarios, including 22 code cart skills, to establish nursing code cart competency. The cohort of PICU RNs underwent a competency assessment in training 1. To achieve competence, the participating RN received immediate feedback and instruction and repeated each task until mastery during training 1. The competencies were repeated 6 months later, designated training 2.Thirty-two RNs participated in training 1. Sixteen RNs (50%) completed the second training. Our rolling-refresher training programme resulted in a 43% reduction in the odds of first attempt failures between training 1 and training 2 (p=0.01). Multivariate linear regression evaluating the difference in first attempt failure between training 1 and training 2 revealed that the following covariates were not significantly associated with this improvement: interval Paediatric Advanced Life Support training, interval use of the code cart or defibrillator (either real or simulated) and time between training sessions. Univariate analysis between the two trainings revealed a statistically significant reduction in first attempt failures for: preparing an epinephrine infusion (72% vs 41%, p=0.04) and providing bag-mask ventilation (28% vs 0%, p=0.02).Our rolling-refresher training programme demonstrated significant improvement in performance for low-frequency, high-risk skills required to manage a paediatric code cart with retention after initial training.

    View details for DOI 10.1136/bmjstel-2017-000243

    View details for Web of Science ID 000429732000007

    View details for PubMedID 29670762

    View details for PubMedCentralID PMC5890621

  • Vessel and Mast Cell Densities in Sporadic and Syndrome-associated Peripheral Nerve Sheath Tumors ANTICANCER RESEARCH Friedrich, R. E., Naber, U., Glatzel, M., Hagel, C. 2015; 35 (9): 4713-4722


    Peripheral nerve sheath (PNS) tumors constitute a heterogeneous group of solid tumors. Neurofibroma and schwannoma are the most frequently diagnosed entities. Both tumor types occur sporadically and are associated with syndromes. Current strategies to fight PNS progression by means of pharmaceuticals aim to specifically interfere with vascular growth factors identified in PNS. Furthermore, malignant transformation of PNS tumors is known to be associated with a change in vascularization. The aim of the study was to investigate vascularization of different PNS tumors with respect to sporadic or syndromal state of the entities.One hundred and thirty-two formalin-fixed and paraffin-embedded PNS tissue samples were retrieved from the archives of the Institute of Neuropathology, Eppendorf University Hospital. Lymphatic and blood vessels were immunohistochemically identified and morphometrically analyzed in PNS and controls.Blood vessel density in malignant tumors was significantly higher than in benign lesions (30.8/mm(2) vs. 13.46/mm(2)). In the latter, the vessel density resembled that of control tissue. Lymphatic vessel supply was significantly higher in cutaneous neurofibroma and diffuse plexiform neurofibroma (PNF) than in intra-neural localized tumors (schwannoma, nodular PNF). Lymphatic vessels showed no marked differences with respect to tumor entity. Prevalence of mast cells differed markedly between tumor types.Different vascularization of PNS may contribute to diverging tumor response following application of anti-neoplastic drugs. Mast cells may have an impact during formation and growth of neurofibroma but are unlikely to be involved in the process of de-differentiation.

    View details for Web of Science ID 000359311000019

    View details for PubMedID 26254361

  • The interplay of donor-specific antibodies, allograft C4d deposition, and antibody-mediated rejection PEDIATRIC TRANSPLANTATION Naber, U., Feingold, B. 2013; 17 (5): 409-411

    View details for DOI 10.1111/petr.12097

    View details for Web of Science ID 000321254700005

    View details for PubMedID 23672434

  • Podoplanin and CD34 in peripheral nerve sheath tumours: focus on neurofibromatosis 1-associated atypical neurofibroma JOURNAL OF NEURO-ONCOLOGY Naber, U., Friedrich, R. E., Glatzel, M., Mautner, V. F., Hagel, C. 2011; 103 (2): 239-245


    Patients suffering from neurofibromatosis type 1 and 2 (NF1 and NF2) are the main risk groups to develop peripheral nerve sheath tumours (PNSTs). In the present study, adhesion molecules CD34 and podoplanin were assessed in regard to their value for tumour classification and as indicators for tumour progression. A total of 103 NF1-, NF2- and schwannomatosis-associated neurofibromas, schwannomas and malignant peripheral nerve sheath tumours (MPNST), as well as 20 sporadic vestibular schwannomas and 9 control tissue samples, were labelled immunohistochemically for detection of podoplanin and CD34. CD34 was shown to be expressed in MPNST and all benign PNSTs except for the compact cellular parts of both, schwannomas and atypical neurofibromas. Podoplanin showed an inverse expression pattern to CD34 labelling mainly the compact parts of schwannoma and atypical neurofibroma. MPNSTs were characterized by strong podoplanin staining at the invasive front. NF1-patients who suffered from atypical neurofibromas did not develop MPNST at a higher frequency than other NF1-patients, although these tumours expressed podoplanin. Ki-67 proliferation indices did not differ significantly between neurofibromas, atypical neurofibromas and schwannomas. In accordance with other studies, CD34 was found to be of limited value for classification and grading of PNST due to its ubiquitous expression. Podoplanin expression in schwannoma and atypical neurofibroma adds to other phenotypic and genotypic similarities between these tumours, like nuclear atypia, regressive changes and euploid polyploidisation. Podoplanin expression in atypical neurofibroma was not associated with tumour progression towards MPNST.

    View details for DOI 10.1007/s11060-010-0385-4

    View details for Web of Science ID 000290773100007

    View details for PubMedID 20821344