Multiple Cardiac Rhabdomyomas Visualised Using Micro-CT in a Case of Tuberous Sclerosis

Cardiac rhabdomyoma is the most common tumour of the heart in infancy and childhood, representing approximately 60% of all primary cardiac tumours in these age groups. Though they have a tendency to regress with advancing age and are histologically benign, rhabdomyomas may cause mechanical obstruction to blood flow, arrhythmia, congestive cardiac failure and death and may be associated with underlying genetic syndromes such as tuberous sclerosis. We present the case of a primigravida in her early 20s with no significant medical history who was referred to the Fetal Medicine Unit at 34 weeks' gestation following the detection of an irregular fetal heartbeat. An anomaly scan at 20 weeks had been reported as normal

Post-mortem micro-CT for non-invasive autopsies: Experience in > 250 human fetuses

BACKGROUND: Non-invasive 'imaging' autopsy alternatives for fetuses weighing <500g are limited. Micro-CT has been reported as a viable option in small case series with the potential to avoid an invasive autopsy. Implementation of post-mortem micro-CT in a large cohort, as part of routine clinical service has yet been unreported and realistic 'autopsy prevention rates' are unknown. OBJECTIVE: To describe the range of abnormalities detectable on fetal micro-CT in a clinical setting, additional findings identified over the antenatal ultrasound, and to estimate the invasive 'autopsy avoidance rate' (i.e. cases where imaging was sufficient to deem autopsy unnecessary). STUDY DESIGN: A prospective observational case series was conducted over 3 years (2016 - 2019), of all fetuses referred for micro-CT imaging at a single institution. Imaging was reported by two paediatric radiologists prior to autopsy, with "decision to proceed" based on specialist perinatal pathologists' judgement and parental consent. Agreement rates between micro-CT and antenatal ultrasound were evaluated, and where feasible, diagnostic accuracy for micro-CT was calculated using autopsy as reference standard. RESULTS: 268 fetuses were included (2-350g weight; 11 - 24 weeks gestation), with cause for demise in 122/268 (45.5%). Of these, 64/122 (52.5%) demonstrated fetal anomalies. Although 221/268 (82.5%) had consent for invasive autopsy, only 29/221 (13.1%) underwent this procedure giving an 'autopsy avoidance rate' of 192/221 (86.9%). Complete agreement was present for all brain, thoracic and abdominal pathologies, whilst sensitivity and specificity for cardiac anomalies were 66.7% and 91.7% respectively. Micro-CT and antenatal ultrasound agreement was found in 219/266 (81.9%) cases, with partial agreement in 21/266 (7.9%) and disagreement in 26/266 (10.5%), mostly due to additional cardiac, soft tissue or genito-urinary findings by micro-CT, not seen at ultrasound. CONCLUSIONS: Fetal micro-CT imaging is a viable and useful tool for imaging early gestational fetuses, and can avoid the need for invasive autopsy. Confirmation of antenatal diagnoses are achieved in the majority, and additional anomalies may also be detected

Micro-CT of tracheal stenosis in trisomy 21

A male infant with trisomy 21, born at 36 weeks' gestation, had care withdrawn at 2 months of age and was referred for postmortem investigations. The child had been ventilator dependent since the first week of life following surgery for intestinal perforation from necrotising enterocolitis. A CT thorax at 1 month of age demonstrated a tight tracheal stenosis, inferior to the tip of the endotracheal tube, with a luminal diameter of 1.2 mm over a length of 1 cm (figure 1). There were no associated cardiovascular or bronchial tree anomalies. Despite efforts to optimise the child’s condition for tracheal reconstruction, he was subsequently found to have an underlying immune deficit disorder with profound lymphopenia and continued to require iontropic support for haemodynamic compromise. After a further month of expectant clinical management without improvement, care was withdrawn

Evolution of context dependent regulation by expansion of feast/famine regulatory proteins

BACKGROUND: Expansion of transcription factors is believed to have played a crucial role in evolution of all organisms by enabling them to deal with dynamic environments and colonize new environments. We investigated how the expansion of the Feast/Famine Regulatory Protein (FFRP) or Lrp-like proteins into an eight-member family in Halobacterium salinarum NRC-1 has aided in niche-adaptation of this archaeon to a complex and dynamically changing hypersaline environment.RESULTS: We mapped genome-wide binding locations for all eight FFRPs, investigated their preference for binding different effector molecules, and identified the contexts in which they act by analyzing transcriptional responses across 35 growth conditions that mimic different environmental and nutritional conditions this organism is likely to encounter in the wild. Integrative analysis of these data constructed an FFRP regulatory network with conditionally active states that reveal how interrelated variations in DNA-binding domains, effector-molecule preferences, and binding sites in target gene promoters have tuned the functions of each FFRP to the environments in which they act. We demonstrate how conditional regulation of similar genes by two FFRPs, AsnC (an activator) and VNG1237C (a repressor), have striking environment-specific fitness consequences for oxidative stress management and growth, respectively.CONCLUSIONS: This study provides a systems perspective into the evolutionary process by which gene duplication within a transcription factor family contributes to environment-specific adaptation of an organism

Reference ranges for organ weights of infants at autopsy: results of >1,000 consecutive cases from a single centre.

Infancy is the most common period for childhood death, including both neonatal deaths from obstetric or medical complications and sudden unexpected infant deaths. The weighing of organs at autopsy is an established process and is recommended in current protocols. However, minimal contemporary data is available regarding reference ranges for organ weights of infants

Reappraising myocardial fibrosis in severe aortic stenosis: an invasive and non-invasive study in 133 patients

Aims: To investigate myocardial fibrosis (MF) in a large series of severe aortic stenosis (AS) patients using invasive biopsy and non-invasive imaging. Methods and results: One hundred thirty-three patients with severe, symptomatic AS accepted for surgical aortic valve replacement underwent cardiovascular magnetic resonance (CMR) with late gadolinium enhancement (LGE) and extracellular volume fraction (ECV) quantification. Intra-operative left ventricular (LV) biopsies were performed by needle or scalpel, yielding tissue with (n = 53) and without endocardium (n = 80), and compared with 10 controls. Myocardial fibrosis occurred in three patterns: (i) thickened endocardium with a fibrotic layer; (ii) microscopic scars, with a subendomyocardial predominance; and (iii) diffuse interstitial fibrosis. Collagen volume fraction (CVF) was elevated (P < 0.001) compared with controls, and higher (P < 0.001) in endocardium-containing samples with a decreasing CVF gradient from the subendocardium (P = 0.001). Late gadolinium enhancement correlated with CVF (P < 0.001) but not ECV. Both LGE and ECV correlated independently (P < 0.001) with N-terminal pro-brain natriuretic peptide and high-sensitivity-troponin T. High ECV was also associated with worse LV remodelling, left ventricular ejection fraction and functional capacity. Combining high ECV and LGE better identified patients with more adverse LV remodelling, blood biomarkers and histological parameters, and worse functional capacity than each parameter alone. Conclusion: Myocardial fibrosis in severe AS is complex, but three main patterns exist: endocardial fibrosis, microscars (mainly in the subendomyocardium), and diffuse interstitial fibrosis. Neither histological CVF nor the CMR parameters ECV and LGE capture fibrosis in its totality. A combined, multi-parametric approach with ECV and LGE allows best stratification of AS patients according to the response of the myocardial collagen matrix

Filamin A (FLNA) mutation—A newcomer to the childhood interstitial lung disease (ChILD) classification

AIM: Interstitial lung disease (ILD) in infants represents a rare and heterogenous group of disorders, distinct from those occurring in adults. In recent years a new entity within this category is being recognized, namely filamin A (FLNA) mutation related lung disease. Our aims are to describe the clinical and radiological course of patients with this disease entity to aid clinicians in the prognostic counseling and management of similar patients they may encounter. METHOD: A retrospective case note review was conducted of all patients treated at our institution (a specialist tertiary referral childrens’ center) for genetically confirmed FLNA mutation related lung disease. The clinical presentation, evolution, management and radiological features were recorded and a medical literature review of Medline indexed articles was conducted. RESULTS: We present a case series of four patients with interstitial lung disease and genetically confirmed abnormalities within the FLNA gene. Their imaging findings all reveal a pattern of predominantly upper lobe overinflation, coarse pulmonary lobular septal thickening and diffuse patchy atelectasis. The clinical outcomes of our patients have been variable ranging from infant death, lobar resection and need for supplemental oxygen and bronchodilators. CONCLUSION: The progressive nature of the pulmonary aspect of this disorder and need for early aggressive supportive treatment make identification crucial to patient management and prognostic counseling

Parallel RNA interference screens identify EGFR activation as an escape mechanism in FGFR3-mutant cancer.

Activation of fibroblast growth factor receptors (FGFR) is a common oncogenic event. Little is known about the determinants of sensitivity to FGFR inhibition and how these may vary between different oncogenic FGFRs. Using parallel RNA interference (RNAi) genetic screens, we show that the EGF receptor (EGFR) limits sensitivity to FGFR inhibition in FGFR3-mutant and -translocated cell lines, but not in other FGFR-driven cell lines. We also identify two distinct mechanisms through which EGFR limits sensitivity. In partially FGFR3-dependent lines, inhibition of FGFR3 results in transient downregulation of mitogen-activated protein kinase signaling that is rescued by rapid upregulation of EGFR signaling. In cell lines that are intrinsically resistant to FGFR inhibition, EGFR dominates signaling via repression of FGFR3, with EGFR inhibition rescued by delayed upregulation of FGFR3 expression. Importantly, combinations of FGFR and EGFR inhibitors overcome these resistance mechanisms in vitro and in vivo. Our results illustrate the power of parallel RNAi screens in identifying common resistance mechanisms to targeted therapies. SIGNIFICANCE: Our data identify a novel therapeutic approach to the treatment of FGFR3-mutant cancer, emphasizing the potential of combination approaches targeting both FGFR3 and EGFR. Our data extend the role of EGFR in mediating resistance to inhibitors targeting a mutant oncogene, showing that EGFR signaling can repress mutant FGFR3 to induce intrinsic resistance to FGFR targeting

Preclinical Optimization and Safety Studies of a New Lentiviral Gene Therapy for p47phox-Deficient Chronic Granulomatous Disease

Chronic granulomatous disease (CGD) is an inherited blood disorder that renders patients susceptible to infections and inflammation. A recent clinical trial of lentiviral gene therapy for the most frequent form of CGD, X-linked, has demonstrated stable correction over time, with no adverse events related to the gene therapy procedure. We have recently developed a parallel lentiviral vector for p47-deficient CGD (p47phoxCGD), the second most common form of this disease. Using this vector, we have observed biochemical correction of CGD in a mouse model of the disease. In preparation for clinical trial approval, we have performed standardised pre-clinical studies following Good Laboratory Practice (GLP) principles, to assess the safety of the gene therapy procedure. We report no evidence of adverse events, including mutagenesis and tumourigenesis, in human haematopoietic stem cells transduced with the lentiviral vector. Biodistribution studies of transduced human CD34+ cells indicate that the homing properties or engraftment ability of the stem cells is not negatively affected. CD34+ cells derived from a p47phoxCGD patient were subjected to an optimised transduction protocol and transplanted into immunocompromised mice. After the procedure, patient-derived neutrophils resumed NADPH oxidase production in vivo, suggesting that gene correction was successful. These studies pave the way to a first-in-man clinical trial of lentiviral gene therapy for the treatment of p47phoxCGD

Difference in expression between AQP1 and AQP5 in porcine endometrium and myometrium in response to steroid hormones, oxytocin, arachidonic acid, forskolin and cAMP during the mid-luteal phase of the estrous cycle and luteolysis

BACKGROUND: Recently, we demonstrated in vitro that AQP1 and AQP5 in the porcine uterus are regulated by steroid hormones (P4, E2), arachidonic acid (AA), forskolin (FSK) and cAMP during the estrous cycle. However, the potential of the porcine separated uterine tissues, the endometrium and myometrium, to express these AQPs remains unknown. Thus, in this study, the responses of AQP1 and AQP5 to P4, E2 oxytocin (OT), AA, FSK and cAMP in the porcine endometrium and myometrium were examined during the mid-luteal phase of the estrous cycle and luteolysis.METHODS: Real-time PCR and western blot analysis.RESULTS: Progesterone up-regulated the expression of AQP1/AQP5 mRNAs and proteins in the endometrium and myometrium, especially during luteolysis. Similarly, E2 also stimulated the expression of both AQPs, but only in the endometrium. AA led to the upregulation of AQP1/AQP5 in the endometrium during luteolysis. In turn, OT increased the expression of AQP1/AQP5 mRNAs and proteins in the myometrium during mid-luteal phase. Moreover, a stimulatory effect of forskolin and cAMP on the expression of AQP1/AQP5 mRNAs and proteins in the endometrium and myometrium dominated during luteolysis, but during the mid-luteal phase their influence on the expression of these AQPs was differentiated depending on the type of tissue and the incubation duration.CONCLUSIONS: These results seem to indicate that uterine tissues; endometrium and myometrium, exhibit their own AQP expression profiles in response to examined factors. Moreover, the responses of AQP1/AQP5 at mRNA and protein levels to the studied factors in the endometrium and myometrium are more pronounced during luteolysis. This suggests that the above effects of the studied factors are connected with morphological and physiological changes taking place in the pig uterus during the estrous cycle.</p