Evaluating adult cor triatriatum with total anomalous pulmonary venous connections by multidetector computed tomography angiography

A 19-year-old female patient was admitted to our hospital with dyspnea, chest pain, and shortness of breath. A chest radiograph showed mild cardiomegaly. Echocardiography revealed an extra chamber in the heart. To evaluate this abnormality, ECG-gated 16-detector-row computed tomography angiography was performed. Multidetector computed tomography (MDCT), showing cor triatriatum with total anomalous pulmonary venous connections (TAPVC), clearly revealed cardiac and vascular anatomy. ECG-gated cardiac MDCT is a useful tool for detection and characterisation of cor triatriatum and related anomalies. (Folia Morphol 2011; 70, 4: 312–314

Determination of anomalous pulmonary venous return with high-pitch low-dose computed tomography in paediatric patients

Background: In this study, we aimed to image pulmonary venous return anomalies and associated cardiovascular and pulmonary abnormalities by high-pitch low-dose computed tomography (CT) in children. Materials and methods: Forty-one patients with total or partial anomalous pulmonary venous return anomalous between May 2012 and June 2019 were retrospectively reviewed. The anomalies were determined using high-pitch low-dose CT. The patients’ mean age was 3 years (6 months to 15 years), and 24 of them were female. Results: There were 10 patients with total pulmonary venous return anomalies (TPVRA) and 31 patients with partial pulmonary venous return anomalies (PPVRA). Six (60%) patients with TPVRA had the supracardiac type, 2 (20%) had the cardiac type, and 2 (20%) had the mixed type. All patients with TPVRA had a large atrial septal defect (ASD), 1 patient also had patent ductus arteriosus, and 1 patient had right cardiac hypertrophy. Forty cases of PPVRA were found in 31 patients. Twenty-seven (67%) of them were right-sided, and 13 were left-sided (33%). Twenty (65%) patients also had an additional cardiovascular anomaly (ASD in 12 patients, persistent superior vena cava in 4 patients, patent ductus arteriosus in 3 patients, and aortic coarctation in 2 patients). Of the 27 patients with right-sided PPVRA, it drained into the superior vena cava in 19 patients, the right atrium in 5 patients, and the inferior vena cava in 3 patients. In left-sided cases, the anomalous pulmonary vein drained into the left innominate vein in 9 patients, and in 4 patients, there were accessory pulmonary veins that drained into the left innominate vein. Many of the patients had additional lung anomalies, including pneumonic infiltration (n = 12), atelectasis (n = 8), and lobar emphysema (n = 5), and some of these findings coexisted. Conclusions: Anomalous pulmonary venous drains and associated cardiac and extra-cardiac anomalies can be detected reliably and quickly with high-pitch low-dose CT without sedation in paediatric patients

Pruning Edge Research with Latency Shears

Edge computing has gained attention from both academia and industry by pursuing two significant challenges: 1) moving latency critical services closer to the users, 2) saving network bandwidth by aggregating large flows before sending them to the cloud. While the rationale appeared sound at its inception almost a decade ago, several current trends are impacting it. Clouds have spread geographically reducing end-user latency, mobile phones? computing capabilities are improving, and network bandwidth at the core keeps increasing. In this paper, we scrutinize edge computing, examining its outlook and future in the context of these trends. We perform extensive client-to-cloud measurements using RIPE Atlas, and show that latency reduction as motivation for edge is not as persuasive as once believed; for most applications the cloud is already 'close enough' for majority of the world's population. This implies that edge computing may only be applicable for certain application niches, as opposed to a general-purpose solution.Peer reviewe

Brain MR Spectroscopy Changes Precede Frontotemporal Lobar Degeneration Phenoconversion in Mapt Mutation Carriers.

Background and purposeThe objective of this study was to longitudinally investigate the trajectory of change in 1 H MRS measurements in asymptomatic MAPT mutation carriers who became symptomatic during follow-up, and to determine the time at which the neurochemical alterations accelerated during disease progression.MethodsWe identified eight MAPT mutations carriers who transitioned from asymptomatic to symptomatic disease during follow-up. All participants were longitudinally followed with an average of 7.75 years (range 4-11 years) and underwent two or more single voxel 1 H MRS examinations from the posterior cingulate voxel, with a total of 60 examinations. The rate of longitudinal change for each metabolite was estimated using linear mixed models. A flex point model was used to estimate the flex time point of the change in slope.ResultsThe decrease in the NAA/mI ratio accelerated 2.09 years prior to symptom onset, and continued to decline. A similar trajectory was observed in the presumed glial marker mI/Cr ratio accelerating 1.86 years prior to symptom onset.ConclusionsOur findings support the potential use of longitudinal 1 H MRS for monitoring the neurodegenerative progression in MAPT mutation carriers starting from the asymptomatic stage

Rates of lobar atrophy in asymptomatic MAPT mutation carriers.

IntroductionThe aim of this study was to investigate the rates of lobar atrophy in the asymptomatic microtubule-associated protein tau (MAPT) mutation carriers.MethodsMAPT mutation carriers (n = 14; 10 asymptomatic, 4 converters from asymptomatic to symptomatic) and noncarriers (n = 13) underwent structural magnetic resonance imaging and were followed annually with a median of 9.2 years. Longitudinal changes in lobar atrophy were analyzed using the tensor-based morphometry with symmetric normalization algorithm.ResultsThe rate of temporal lobe atrophy in asymptomatic MAPT mutation carriers was faster than that in noncarriers. Although the greatest rate of atrophy was observed in the temporal lobe in converters, they also had increased atrophy rates in the frontal and parietal lobes compared to noncarriers.DiscussionAccelerated decline in temporal lobe volume occurs in asymptomatic MAPT mutation carriers followed by the frontal and parietal lobe in those who have become symptomatic. The findings have implications for monitoring the progression of neurodegeneration during clinical trials in asymptomatic MAPT mutation carriers

Midlife and Late-Life Vascular Risk Factors and White Matter Microstructural Integrity: The Atherosclerosis Risk in Communities Neurocognitive Study.

BACKGROUND: Diffusion tensor imaging measures of white matter (WM) microstructural integrity appear to provide earlier indication of WM injury than WM hyperintensities; however, risk factors for poor WM microstructural integrity have not been established. Our study quantifies the association between vascular risk factors in midlife and late life with measures of late-life WM microstructural integrity. METHODS AND RESULTS: We used data from 1851 participants in ARIC (Atherosclerosis Risk in Communities Study) who completed 3-T magnetic resonance imaging, including diffusion tensor imaging, as part of the ARIC Neurocognitive Study (ARIC-NCS). We quantified the association among lipids, glucose, and blood pressure from the baseline ARIC visit (1987-1989, ages 44-65, midlife) and visit 5 of ARIC (2011-2013, ages 67-90, late life, concurrent with ARIC-NCS) with regional and overall WM mean diffusivity and fractional anisotropy obtained at ARIC visit 5 for ARIC participants. We also considered whether these associations were independent of or modified by WM hyperintensity volumes. We found that elevated blood pressure in midlife and late life and elevated glucose in midlife, but not late life, were associated with worse late-life WM microstructural integrity. These associations were independent of the degree of WM hyperintensity, and the association between glucose and WM microstructural integrity appeared stronger for those with the least WM hyperintensity. There was little support for an adverse association between lipids and WM microstructural integrity. CONCLUSIONS: Hypertension in both midlife and late life and elevated glucose in midlife are related to worse WM microstructural integrity in late life

Spontaneous Formation and Rearrangement of Artificial Lipid Nanotube Networks as a Bottom-Up Model for Endoplasmic Reticulum

We present a convenient method to form a bottom-up structural organelle model for the endoplasmic reticulum (ER). The model consists of highly dense lipidic nanotubes that are, in terms of morphology and dynamics, reminiscent of ER. The networks are derived from phospholipid double bilayer membrane patches adhering to a transparent Al2O3 substrate. The adhesion is mediated by Ca2+ in the ambient buffer. Subsequent depletion of Ca2+ by means of BAPTA/EDTA causes retraction of the membrane, resulting in spontaneous lipid nanotube network formation. The method only comprises phospholipids and microfabricated surfaces for simple formation of an ER model and does not require the addition of proteins or chemical energy (e.g., GTP or ATP). In contrast to the 3D morphology of the cellular endoplasmic reticulum, the model is two-dimensional (albeit the nanotube dimensions, geometry, structure, and dynamics are maintained). This unique in vitro ER model consists of only a few components, is easy to construct, and can be observed under a light microscope. The resulting structure can be further decorated for additional functionality, such as the addition of ER-associated proteins or particles to study transport phenomena among the tubes. The artificial networks described here are suitable structural models for the cellular ER, whose unique characteristic morphology has been shown to be related to its biological function, whereas details regarding formation of the tubular domain and rearrangements within are still not completely understood. We note that this method uses Al2O3 thin-film-coated microscopy coverslips, which are commercially available but require special orders. Therefore, it is advisable to have access to a microfabrication facility for preparation

Frequency and topography of cerebral microbleeds in dementia with Lewy bodies compared to Alzheimer's disease

AbstractAimTo determine the frequency and topographic distribution of cerebral microbleeds (CMBs) in dementia with Lewy bodies (DLB) in comparison to CMBs in Alzheimer disease dementia (AD).MethodsConsecutive probable DLB (n = 23) patients who underwent 3-T T2* weighted gradient-recalled-echo MRI, and age and gender matched probable Alzheimer's disease patients (n = 46) were compared for the frequency and location of CMBs.ResultsThe frequency of one or more CMBs was similar among patients with DLB (30%) and AD (24%). Highest densities of CMBs were found in the occipital lobes of patients with both DLB and AD. Patients with AD had greater densities of CMBs in the parietal, temporal lobes and infratentorial regions compared to DLB (p < 0.05).ConclusionCMBs are as common in patients with DLB as in patients with AD, with highest densities observed in the occipital lobes, suggesting common pathophysiologic mechanisms underlying CMBs in both diseases

Efficacy of ivabradin to reduce heart rate prior to coronary CT angiography: Comparison with beta-blocker

PURPOSE: The objective of our study was to assess the effect of ivabra-dine on image quality of ECG-gated multidetector computed tomography (MDCT) coronary angiography. MATERIALS AND METHODS: Computed tomography coronary angiography (CTCA) was performed on two groups. In Group 1 (n=54), an intravenous beta-blocker was administered to patients with a heart rate >70 beats per minute (bpm) just before CTCA. In Group 2 (n=56), oral ivabradine 5 mg was administered twice a day for three days prior to CTCA examination to patients with a heart rate >70 bpm and contraindication to beta-blockers. Images acquired on two different MDCT scanners were scored in terms of image quality of the coronary artery segments using a 5-point grading scale (Grade 1, unreadable; Grade 5, excellent). RESULTS: The mean heart rates during CTCA were 64±6.7 bpm for Group 1 and 59±4.1 bpm for Group 2 (P < 0.05). Mean heart rate reduction was 9±5% and 14±8% for Groups 1 and 2, respectively (P < 0.001). A total of 880 segments were evaluated in 110 patients. When the best reconstruction interval was used, 89.8% and 95.5% of all the coronary segments showed acceptable image quality in Groups 1 and 2, respectively. Acceptable image quality of the middle right coronary artery was obtained in 78.3% of Group 1 and 92.4% of Group 2. These ratios for the other segments were 88.4% for Group 1 and 95.2% for Group 2. CONCLUSION: Reduction of heart rates with ivabradine premedication improves the image quality of CTCA. It should be considered as an alternative drug, particularly in patients with contraindications to beta-blockers. © Turkish Society of Radiology 2012

Discovering Communities for Microgrids with Spatial-Temporal Net Energy

Smart grid has integrated an increasing number of distributed energy resources to improve the efficiency and flexibility of power generation and consumption as well as the resilience of the power grid. The energy consumers on the power grid, e.g., households, equipped with distributed energy resources can be considered as “microgrids” that both generate and consume electricity. In this paper, we study the energy community discovery problems which identify energy communities for the microgrids to facilitate energy management, e.g., load balancing, energy sharing and trading on the grid. Specifically, we present efficient algorithms to discover such communities of microgrids considering both their geo-locations and net energy (NE) over any period. Finally, we experimentally validate the performance of the algorithms using both synthetic and real datasets