Project description:BackgroundDuring paediatric cardiac Cine-MRI, data acquired during cycles of different lengths must be combined. Most of the time, Feinstein's model is used to project multiple cardiac cycles of variable lengths into a mean cycle.ObjectiveTo assess the effect of Feinstein projection on temporal resolution of Cine-MRI.Methods1/The temporal errors during Feinstein's projection were computed in 306 cardiac cycles fully characterized by tissue Doppler imaging with 6-phase analysis (from a population of 7 children and young adults). 2/The effects of these temporal errors on tissue velocities were assessed by simulating typical tissue phase mapping acquisitions and reconstructions. 3/Myocardial velocities curves, extracted from high-resolution phase-contrast cine images, were compared for the 6 volunteers with lowest and highest heart rate variability, within a population of 36 young adults.Results1/The mean of temporal misalignments was 30 ms over the cardiac cycle but reached 60 ms during early diastole. 2/During phase contrast MRI simulation, early diastole velocity peaks were diminished by 6.1 cm/s leading to virtual disappearance of isovolumic relaxation peaks. 3/The smoothing and erasing of isovolumic relaxation peaks was confirmed on tissue phase mapping velocity curves, between subjects with low and high heart rate variability (p = 0.05).ConclusionsFeinstein cardiac model creates temporal misalignments that impair high temporal resolution phase contrast cine imaging when beat-to-beat heart rate is changing.
Project description:We describe the case of an antenatally diagnosed massive cardiac tumor in a fetus requiring cardiorespiratory support immediately following birth. We further discuss the successful management of this case and highlight the importance of a multidisciplinary team in managing such complicated cases. (Level of Difficulty: Advanced.).
Project description:Cardiac rhabdomyomas are described as sporadic as well as associated with tuberous sclerosis. Association with LVOT obstruction with anorectal malformation or imperforate anus has not been reported so far in published literature. In this case report we describe one such case.
Project description:The long-term prognosis of a fetus with cardiac rhabdomyoma (CR) depends on the correlation with tuberous sclerosis complex (TSC). In recent years, the numerous variations of uncertain significance (VUS) of TSC genes produced by high-throughput sequencing have made counseling challenging, studies until now have tended to side-step the tricky topics. Here, we integrated detailed parental phenotype, echocardiography, neuro MRI, and genetic information to conduct a comprehensive evaluation of 61 CR fetuses. As a result, multiple CRs and cerebral lesions appeared in 90 and 80%, respectively of fetuses with pathogenic (P)/likely pathogenic (LP) TSC1/TSC2 variations. Overall, 85.7% of the live-born infants with P/LP presented with TSC-associated signs. While, 85.7% of VUS without nervous findings had good prognoses. Genetic evidence and cerebral MRI findings are the most sensitive index to assess long-term prognosis, which complement and confirm each other for a TSC diagnosis. In total, 68.9% of fetuses with CR could benefit from this multidisciplinary approach, which turned out to be potentially clinically actionable with precise clinical/genetic diagnosis or had a foreseeable outcome. Our practice provides a practical and feasible solution for perinatal management and prognostic guidance for fetuses with CR.
Project description:The brightness of aurorae in Earth's polar region often beats with periods ranging from sub-second to a few tens of a second. Past observations showed that the beat of the aurora is composed of a superposition of two independent periodicities that co-exist hierarchically. However, the origin of such multiple time-scale beats in aurora remains poorly understood due to a lack of measurements with sufficiently high temporal resolution. By coordinating experiments using ultrafast auroral imagers deployed in the Arctic with the newly-launched magnetospheric satellite Arase, we succeeded in identifying an excellent agreement between the beats in aurorae and intensity modulations of natural electromagnetic waves in space called "chorus". In particular, sub-second scintillations of aurorae are precisely controlled by fine-scale chirping rhythms in chorus. The observation of this striking correlation demonstrates that resonant interaction between energetic electrons and chorus waves in magnetospheres orchestrates the complex behavior of aurora on Earth and other magnetized planets.
Project description:Rhabdomyoma is a well characterised entity in a neonate. Herein, we report a massive biventricular rhabdomyoma in a neonate presenting with cyanosis and congestive heart failure which was confirmed on autopsy. The report is for documentation of an unusually large tumour.
Project description:Introduction Rhabdomyoma is a rare benign tumor derived from skeletal muscles. Laryngeal rhabdomyomas are even rarer, with only approximately 40 reported cases in world literature. Laryngeal rhabdomyomas usually are seen as masses covered by mucosa. They are often solitary asymptomatic tumors, but symptoms such as hoarseness can occur. The radiologic features are usually those typical of benign neoplasms, showing well-delineated borders. The differential diagnoses for laryngeal masses include cysts, laryngoceles, and benign and malignant neoplasms. The diagnosis is usually made using histopathologic findings, but in some cases some difficulties can be found. Immunohistochemical staining is of great value in the differentiation of similar tumors. Treatment of rhabdomyoma is surgical excision. Objective To describe a case of rhabdomyoma of the larynx attended at Santa Casa de Misericórdia do Rio de Janeiro. Case Report A 35-year-old man presented with progressive hoarseness in the preceding year. Laryngoscopy showed a large submucosal tumor at the supraglottic region of the larynx. The neck computed tomography scan confirmed the submucosal mass, with distinct borders. The patient was taken to the operating suite, where endoscopic extirpation of the mass was performed. Initial histologic diagnosis was suggestive of paraganglioma, which was not confirmed by studies with immunohistochemical markers, and diagnosis was changed to adult-type rhabdomyoma. The patient recovered well. His voice returned to normal after 3 months. Discussion Although muscle tumors of the larynx are very rare, rhabdomyoma should be considered when there is a submucosal mass in the larynx.
Project description:Dermatomyositis (DM), a myopathy associated with inflammation and muscle weakness, has historically been difficult to diagnose. Recently, nuclear matrix protein (NXP-2) antibodies have been described as a myositis-specific antibody that may aid in the diagnostic evaluation. We present the case of a 21-year-old, previously healthy, African American male with DM. He presented to our outpatient clinic with periorbital swelling and a rash, for which he was started on prednisone by an ophthalmologist. Towards the end of the prednisone taper, he began to experience muscle weakness, a worsening rash, and dysphagia to solids with a resultant loss of 60 pounds within a month. He was transferred to a tertiary care hospital where he was further evaluated and ultimately diagnosed with dermatomyositis, supported by skin and muscle biopsies, and was found to be positive for NXP-2. He was given intravenous immunoglobulin (IVIG) and high-dose steroids with improvement.
Project description:Identification of genomic regions that control tissue-specific gene expression is currently problematic. ChIP and high-throughput sequencing (ChIP-seq) of enhancer-associated proteins such as p300 identifies some but not all enhancers active in a tissue. Here we show that co-occupancy of a chromatin region by multiple transcription factors (TFs) identifies a distinct set of enhancers. GATA-binding protein 4 (GATA4), NK2 transcription factor-related, locus 5 (NKX2-5), T-box 5 (TBX5), serum response factor (SRF), and myocyte-enhancer factor 2A (MEF2A), here referred to as "cardiac TFs," have been hypothesized to collaborate to direct cardiac gene expression. Using a modified ChIP-seq procedure, we defined chromatin occupancy by these TFs and p300 genome wide and provided unbiased support for this hypothesis. We used this principle to show that co-occupancy of a chromatin region by multiple TFs can be used to identify cardiac enhancers. Of 13 such regions tested in transient transgenic embryos, seven (54%) drove cardiac gene expression. Among these regions were three cardiac-specific enhancers of Gata4, Srf, and swItch/sucrose nonfermentable-related, matrix-associated, actin-dependent regulator of chromatin, subfamily d, member 3 (Smarcd3), an epigenetic regulator of cardiac gene expression. Multiple cardiac TFs and p300-bound regions were associated with cardiac-enriched genes and with functional annotations related to heart development. Importantly, the large majority (1,375/1,715) of loci bound by multiple cardiac TFs did not overlap loci bound by p300. Our data identify thousands of prospective cardiac regulatory sequences and indicate that multiple TF co-occupancy of a genomic region identifies developmentally relevant enhancers that are largely distinct from p300-associated enhancers.
Project description:Heart failure (HF) is a serious condition in which the support of blood pumped by the heart is insufficient to meet the demands of body at a normal cardiac filling pressure. Approximately 26 million patients worldwide are suffering from heart failure and about 17-45% of patients with heart failure die within 1-year, and the majority die within 5-years admitted to a hospital. The molecular mechanisms underlying the progression of heart failure have been poorly studied. We compared the gene expression profiles between patients with heart failure (n = 177) and without heart failure (n = 136) using multiple feature selection strategies and identified 38 HF signature genes. The support vector machine (SVM) classifier based on these 38 genes evaluated with leave-one-out cross validation (LOOCV) achieved great performance with sensitivity of 0.983 and specificity of 0.963. The network analysis suggested that the hub gene SMOC2 may play important roles in HF. Other genes, such as FCN3, HMGN2, and SERPINA3, also showed great promises. Our results can facilitate the early detection of heart failure and can reveal its molecular mechanisms.