bluuebunny/crossref_metadata_2025_split huggingface dataset:
Cardiac CT—basic principles
Authors: Pontone Gianluca , Cademartiri Filippo 
Published: June 2021

Abstract
Computed tomography (CT) was introduced for clinical diagnostic radiology in 1971, and it was used as neuro and body scanner for about 20 years. Spatial and temporal resolution required to evaluate a dynamic structure such as the heart was not sufficient until 1998. Thanks to the technical developments in CT technology over the past 20 years cardiac CT (CCT) developed from an investigative tool into an established clinical tool primarily used as non-invasive clinical diagnostic test for coronary artery imaging. The key technical development occurred in the late 1990s with the introduction of multidetector CT (4 slices) scanners able to synchronize image acquisition and reconstruction with an electrocardiographic (ECG) track. However, 4-slice and also the following 16-slice CT technology had technical limitations, such as limited coverage and temporal resolution, but which allowed diagnostic image quality in selected patients with low and stable heart rate. Moreover, relatively high radiation exposure was required to obtain clinically valid image quality. For this reason, different technical strategies were developed in the following years and advances were also provided in the field of reconstruction algorithm with the introduction of iterative algorithms that allowed an image noise reduction and in the field of tissue characterization with the use of dual-energy CT. All these advances allowed CCT to become a pivotal tool in the cardiology daily practice to image the coronary arteries and beyond.
Tricuspid and pulmonary valve disease
Authors: Muraru Denisa , Sade Elif Leyla 
Published: June 2021

Abstract
Right heart valves have gained significant interest in the context of a plethora of new emerging percutaneous transcatheter interventions for treating tricuspid and pulmonary valve diseases. Multimodality imaging is pivotal for patient diagnosis, management, and prognosis, as well as for planning interventional and surgical valve procedures. Echocardiography is the primary imaging modality for initial diagnosis and longitudinal follow-up of patients with right-sided valvular heart disease. Cardiovascular magnetic resonance has emerged as a complementary or alternative modality for providing diagnostic information on the tricuspid and pulmonary valve anatomy, and particularly on the pulmonary artery and the consequences on the right ventricle. This chapter highlights the current use of various imaging modalities for the state-of-the-art assessment of right-sided valvular heart diseases, with emphasis on the main clinical indications, as well as on the strengths and limitations of each modality.
Multiple and mixed valvular heart disease
Authors: Unger Philippe , Garbi Madalina 
Published: June 2021

Abstract
Multiple and mixed valvular heart disease are highly prevalent. Multiple valvular heart disease is the combination of stenotic and/or regurgitant lesions occurring on two or more cardiac valves. Mixed valvular heart disease is the combination of stenotic and regurgitant lesions on the same valve. Several haemodynamic interactions may impact their clinical expression and may result in diagnostic pitfalls. Accurate quantification of the valve lesions requires the use of methods that are less dependent on loading conditions, such as planimetry for stenotic lesions, and assessment of the effective regurgitant orifice area and vena contracta for regurgitant lesions. The assessment should address the diagnosis and severity of each single valve lesion as well as the overall consequences resulting from the combination of all lesions. Clinical decision-making should be based on an integrative approach including echocardiography and other imaging modalities.
Evaluation of systolic LV function and LV mechanics
Authors: Hoffmann Rainer , Flachskampf Frank A. 
Published: June 2021

Abstract
Analysis of global and regional left ventricular (LV) function is the most frequent indication to perform echocardiography. While visual assessment based on 2D images is the basis for analysis of LV function, it may be supplemented by quantitative techniques to obtain parameters of global or regional function. 2D echocardiography tends to underestimate LV volumes compared to cardiac magnetic resonance (CMR), 3D echocardiography results in less volume underestimation and high accuracy in the analysis of ejection fraction. Visual analysis of regional function is limited by significant interobserver variability. Another approach to systolic LV function is the assessment of LV mechanics, typically by measuring global longitudinal deformation (strain) by speckle-tracking echocardiography. Alternatively, information on deformation can be obtained from CMR (currently, mostly by feature tracking). Deformation parameters detect early impairment of LV systolic function with higher sensitivity than ejection fraction. While echocardiography continues to be the first-choice modality for ejection fraction, CMR has become the gold standard for quantification of LV volumes and ejection fraction. Nuclear imaging should be applied to assess LV function only if simultaneous assessment of myocardial perfusion is requested.
Imaging of the right heart
Authors: Rudski Lawrence , Nihoyannopoulos Petros , Blissett Sarah 
Published: June 2021

Abstract
The right ventricle has lost its designation as the ‘forgotten ventricle’ over the past decade. Clinicians recognize its prognostic significance in a wide array of disease processes and imagers are now providing an assessment of right ventricular size and function in most studies. Despite this recognition, imaging the right heart presents numerous challenges to the imager. The shape of the chamber, the unique structure, and its coupling to the pulmonary circulation mandate a different approach to its evaluation as compared to the left ventricle. Imaging may be done by several modalities, each with their own strengths and limitations. Even more so than with the left ventricle, the findings must be interpreted in the context of loading conditions and clinical setting. This chapter will focus on the two main right heart imaging modalities—echocardiography and cardiac MRI.
Echocardiography evaluation in extracorporeal support
Authors: Price Susanna , Gambaro Alessia 
Published: June 2021

Abstract
Extracorporeal circuits are increasingly used to support critically ill patients with severe cardiac and/or respiratory failure. They may be used as a bridge to recovery, transplantation, decision for further intervention, or as destination therapy. When undertaking echocardiography for extracorporeal support, certain key principles apply. First, as extracorporeal support is not a treatment per se, but rather a supportive therapy while awaiting resolution of the underlying pathological process echocardiography has a vital role in diagnosing/excluding any potentially treatable underlying cause for cardiorespiratory failure. Second, echocardiography is required to determine the requirement for right and/or left ventricular support, the level of support required, and assessing the ability of the right and left ventricles to support the extracorporeal circuit. This demands that the practitioner understands the different types of circuit, and the load that each will place on the heart. Third, echocardiography is mandatory to exclude cardiovascular contraindications to initiation of support. Echocardiography subsequently has a vital role in its successful implementation, including confirming/guiding correct cannula placement, ensuring the goals of support are met, detecting complications, and assessing tolerance to assistance. Finally, in patients requiring extracorporeal cardiac support, various echocardiographic parameters have been proposed to be used in conjunction with clinical and haemodynamic assessment in order to attempt to predict those patients who can be successfully weaned.
Dilated cardiomyopathy
Authors: Tayal Upasana , Prasad Sanjay , Germans Tjeerd , van Rossum Albert C. 
Published: June 2021

Abstract
Dilated cardiomyopathy (DCM) is characterized by enlargement of the heart with associated reduced left ventricular function. From an imaging perspective, important requirements are to exclude other pathologies, assess disease severity, guide therapeutic management, and identify complications. Establishing the imaging diagnosis of DCM is key to guiding the management of DCM. In this chapter we discuss how to use imaging to make an accurate diagnosis of DCM, and review how to exclude coronary artery disease (CAD) and valvular disease as these are two important differentials with differing management strategies. We then review the diagnostic and prognostic capabilities of echocardiography, cardiovascular magnetic resonance imaging (CMR) and nuclear techniques including single-photon emission computed tomography (SPECT) and positron emission tomography (PET) in DCM, with a focus on where imaging can identify particular causes of DCM.
Aortic disease: Aneurysm and dissection—role of CMR
Authors: Rodriguez-Palomares Jose F. , Evangelista Arturo 
Published: June 2021

Abstract
Cardiovascular magnetic resonance (CMR) is a non-invasive imaging technique that permits the most comprehensive study of aortic diseases since it offers morphological, functional, and biochemical information. Technological advances which have implied faster gradients, newer sequences, and ultrafast angiography, have made CMR the modality of choice for imaging aortic diseases. CMR can be used to define the location and extent of aneurysms, dissections, and aortic wall ulceration. This is the best technique to demonstrate areas of wall thickening related to aortitis or intramural haematoma. Furthermore, CMR may be used as a tool to study aortic physiology by assessment of elastic aortic properties, stiffness, and aortic wall shear stress. This information is obtained without the use of ionizing radiation, and in some instances, without the need of contrast. Thus, CMR is particularly useful in patients with either contraindications to iodinated contrast or in those with aortic diseases that require sequential follow-up.
Correia, Diamond and the Chester Exception: Vindicating Patient Autonomy?
Authors: Austin Louise 
Published: June 2021

Abstract
In Chester v Afshar [2004], the House of Lords stated they were departing from the traditional rules of causation in order to vindicate the patient’s right of autonomy. Subsequent judgments in the Court of Appeal expressed concerns over the lack of clarity of the legal principles to be derived from that judgment. In Correia v University Hospital of North Staffordshire NHS Trust [2017] and Diamond v Royal Devon and Exeter NHS Foundation Trust [2019], however, the Court of Appeal sought to clarify the scope and limits of Chester. This commentary sets out the scope and limits of Chester in light of those judgments and considers the extent to which they can be said to be vindicating patient autonomy. Drawing upon Coggon’s typology of autonomy, it concludes that future judgments should utilise that typology to explicate which understanding of autonomy they are seeking to protect.
Single-round deoxyribozyme discovery
Authors: Streckerová Tereza , Kurfürst Jaroslav , Curtis Edward A 
Published: May 2021

Abstract
Artificial evolution experiments typically use libraries of ∼1015 sequences and require multiple rounds of selection to identify rare variants with a desired activity. Based on the simple structures of some aptamers and nucleic acid enzymes, we hypothesized that functional motifs could be isolated from significantly smaller libraries in a single round of selection followed by high-throughput sequencing. To test this idea, we investigated the catalytic potential of DNA architectures in which twelve or fifteen randomized positions were embedded in a scaffold present in all library members. After incubating in either the presence or absence of lead (which promotes the nonenzymatic cleavage of RNA), library members that cleaved themselves at an RNA linkage were purified by PAGE and characterized by high-throughput sequencing. These selections yielded deoxyribozymes with activities 8- to 30-fold lower than those previously isolated under similar conditions from libraries containing 1014 different sequences, indicating that the disadvantage of using a less diverse pool can be surprisingly small. It was also possible to elucidate the sequence requirements and secondary structures of deoxyribozymes without performing additional experiments. Due to its relative simplicity, we anticipate that this approach will accelerate the discovery of new catalytic DNA and RNA motifs.
ATRT-05. REPURPOSED ANTI-MALARIAL QUINACRINE ACTIVATES P53 AND INHIBITS ATRT TUMORIGENICITY
Authors: Kaur Harpreet , Parthasarathy Akhila , Guo Huizi , Green Peter C , Akhtarkhavari Sepehr , Eberhart Charles G , Raabe Eric H 
Published: June 2021

Abstract
Atypical teratoid rhabdoid tumors (ATRTs) are fatal pediatric brain tumors that warrant improved therapies urgently. ATRTs are characterized by loss of INI1, a subunit of the SWI/SNF chromatin-remodeling complex. ATRTs grow aggressively despite majority of primary tumors expressing p53, suggesting inactivation of this tumor suppressor pathway. Reactivation of p53 could be a potential therapeutic strategy for inhibiting ATRT growth. Our laboratory specializes in researching mechanisms contributing to ATRT pathogenesis and potential therapies. In line with this, we investigated an anti-malarial drug called quinacrine that has been safely used in children for decades and can induce p53 in renal cell carcinoma. We used 5 patient-derived ATRT cell lines (BT-37, BT-12, CHLA-06, CHLA-266, CHLA-05) for our studies. We show that ATRT cell lines treated with quinacrine for 6 hours show increased expression of p53, suggesting its activation. Treatment of ATRT cell lines with increasing doses of quinacrine for 24 hours showed dose-dependent decrease in cell growth and proliferation (assessed by MTS assay and BrdU incorporation, P&lt;0.05) and increase in apoptotic cell death (CC-3 and cleaved PARP expression). Nude mice harboring flank tumors of ATRT cell lines and treated with quinacrine for 3 weeks showed significant reduction in tumor growth compared to control animals (P&lt;0.05). Since quinacrine is a substrate for the drug-efflux proteins P-gp/BCRP, we used quinacrine in combination with elacridar (Pgp/BCRP inhibitor) in our intracranial xenograft experiments to increase quinacrine’s retention in the brain. Mice harboring intracranial xenografts of ATRT cells showed increased survival when treated with quinacrine and elacridar (median survival 46 days) compared to control animals (median survival 25 days). These results suggest that quinacrine inhibits ATRT growth, partly by activating p53. Our studies are the first to show quinacrine’s effect on ATRTs and our current experiments include further investigation of quinacrine’s mechanism.
LGG-02. PEDIATRIC LOW-GRADE GLIOMA RISK STRATIFICATION IN THE MOLECULAR ERA
Authors: Hata Jessica , Barbour Mustafa , Huang Michael Angelo 
Published: June 2021

Abstract

Background
Pediatric low-grade gliomas (LGG), in particular those not amenable to surgical resection, are a therapeutic challenge owing to their heterogeneity in clinical behavior. Identification of the RAS/MAPK pathway as a universal feature of these tumors has led to an improved understanding and the development of targeted therapeutics. We examined the impact of known biological and novel molecular risk factors on patient outcomes at our institution.

Methods
We retrospectively reviewed risk factors and clinical outcomes in 38 LGG cases diagnosed by histopathology at Norton Children’s Hospital in Louisville, KY, USA from March 2015 to Jan 2019. Progression free survival (PFS) rates were generated using the Kaplan-Meier method. Log-rank tests and hazard ratios were used to identify prognostic factors by univariable analysis.

Results
Among previously described biological risk factors, subtotal resection/biopsy only (HR 3.67, p=0.0257), non-WHO Grade I histology (HR 3.34, p=0.0101), and infant age (&lt; 3 years) (HR 4.19, p=0.0031) were associated with shorter PFS. Brainstem location had no significant impact on PFS. (HR 0.86, p=0.8071). H3K27M mutant status was predictably associated with worse PFS (HR 5.86, p=0.0012). BRAF v600e mutant status, however, was not associated with inferior outcomes. On the contrary, in our study population, BRAF v600e mutant status had a suggested protective effect (HR 0.14, p=0.0247). Patients with 2 or more oncogenic driver mutations demonstrated worsened PFS (HR 4.78, p=0.0059). We utilized the following scoring system for risk stratification: 1 point was allocated for each of the above biological and molecular risk factors except for H3K27M, which was allocated 3 points. A score of &lt; 3 was designated low risk. Non-low risk classification was associated with significantly inferior PFS (median PFS 13 vs. 62 mos, HR 4.26, p=0.0012).

Conclusion
We herein demonstrate the utility of a combined biological and molecular risk classification for pediatric LGG.
Comparing the acute effects of shiftwork on mothers and fathers
Authors: Tucker P , Leineweber C , Kecklund G 
Published: May 2021

Abstract

Background
Shift work may impact women more negatively than men due to the increased burden of coping with demanding work schedules while also undertaking more of the domestic chores, including childcare.

Aims
To examine whether the combination of shift working and caring for children affects the sleep, fatigue and work–family conflict experienced by women more than it affects men.

Methods
Using data from a survey of the Swedish working population, mixed linear regression models examined work schedule (daywork, shift work with nights, shift work without nights), gender and presence of children &lt;13 years at home as predictors of sleep insufficiency, sleep disturbance, fatigue and work–family conflict, over up to three successive measurement occasions. Adjustments were made for age, education, full/part-time working and baseline year.

Results
In fully adjusted models (N = 8938), shift work was associated with insufficient sleep (P &lt; 0.01), disturbed sleep (P &lt; 0.01), fatigue (P &lt; 0.05) and work–family conflict (P &lt; 0.001). Interactions in the analyses of sleep disturbance (P &lt; 0.001) and work–family interference (P &lt; 0.05) indicated that among participants with no children, females reported more disturbed sleep and more work–family conflict than their male counterparts, irrespective of schedule; while among participants with children, female dayworkers reported more disturbed sleep than their male counterparts, and females working shifts without nights reported more work–family interference.

Conclusions
Having young children did not exacerbate negative effects of shift work, in either men or women. This may reflect high levels of gender equality and childcare provision in Sweden.
Rice Putative Pectin Methyltransferase Gene OsPMT10 Is Required for Maintaining the Cell Wall Properties of Pistil Transmitting Tissues via Pectin Modification
Authors: Hasegawa Kazuya , Kamada Shihomi , Takehara Shohei , Takeuchi Haruki , Nakamura Atsuko , Satoh Shinobu , Iwai Hiroaki 
Published: May 2021

Abstract
Precise directional control of pollen tube growth via mechanical guidance by pistil tissue is critical for the successful fertilization of flowering plants and requires active cell-to-cell communication and maintenance of softness in the transmitting tissue. However, the regulation of transmitting tissue softness as controlled by cell wall properties, especially pectin, has not been reported. Here we report that regulation of pectin methylesterification supports pollen elongation through pistil transmitting tissues in Oryza sativa. The rice pectin methylesterase gene OsPMT10 was strongly expressed in reproductive tissues, especially the pistil. The ospmt10 mutant did not have a significant effect on vegetative growth, but the fertility rate was reduced by approximately half. In the ospmt10 mutant, pollen tube elongation was observed in the transmitting tissue of the style, but approximately half of the pollen tubes did not extend all the way to the ovule. Tissue cross-sections of the upper ovary were prepared, and immunohistochemical staining using LM19 and LM20 showed that methylesterified pectin distribution was decreased in ospmt10 compared with the wild type. The decreased expression of methylesterified pectins in ospmt10 may have resulted in loss of fluidity in the apoplast space of the transmitting tissue, rendering it difficult for the pollen tube to elongate in the transmitting tissue and thereby preventing it from reaching the ovule.
Pandemic Policymaking in Presidential Federations: Explaining Subnational Responses to Covid-19 in Brazil, Mexico, and the United States
Authors: Bennouna Cyril , Giraudy Agustina , Moncada Eduardo , Rios Eva , Snyder Richard , Testa Paul 
Published: June 2021

AbstractWhy do COVID-19 social distancing policies vary so widely across states in federal countries? This mixed-methods study of Brazil, Mexico, and the United States finds that state-level variation in the stringency of social distancing policies is driven not by the epidemiological, demographic, or socioeconomic factors commonly emphasized in previous research, but largely by political factors. Introducing a novel framework for explaining pandemic policymaking, the study shows the central importance of political parties, presidential power, and governors’ coalitions in determining state-level policy stringency. In the United States and Mexico, statistical and qualitative evidence indicates that interstate collaboration among governors, combined with top-down pressures from national party elites and presidents, led to greater policy alignment among coordinated states. In Brazil, in contrast, where there is little evidence of either policy coordination or alignment, state-level policies resulted instead from intrastate factors and diffusion. Together, these findings highlight how a multilevel framework attuned to varied combinations of intra-unit, cross-unit, and cross-level causal factors strengthens our understanding of pandemic policymaking.
The Upper And Lower Central Series In Linear Groups
Authors: de Giovanni F , Trombetti M , Wehrfritz B A F 
Published: June 2021

Abstract
A classical theorem of Reinhold Baer shows that any group which is finite over its k-th centre has a finite (k + 1)-th term of its lower central series. Although the converse statement is false in general, Philip Hall proved that for any group G the finiteness of γk + 1(G) implies that the index $|G:\zeta_{2k}(G)|$ is finite. Similar situations have been investigated when finiteness is replaced by suitable weaker conditions. Moreover, it was proved by Yuri${\text{\u{\i}}}$ Merzljakov that Baer’s theorem and its potential converse do hold for linear groups. The aim of this paper is to obtain results of the latter type for several other finiteness conditions.
Finally, although a result of Baer type does not hold for the class of soluble-by-finite reduced minimax groups, we prove that for this class a theorem of Hall type is true in arbitrary groups.
Repair calvarial defect of osteoporotic rats by berberine functionalized porous calcium phosphate scaffold
Authors: Wang Dahao , Zhang Peng , Mei Xifan , Chen Zhenhua 
Published: June 2021

Abstract
In this article, we propose a simple scheme of using berberine (BBR) to modify porous calcium phosphate ceramics (named PCPC). These BBR molecules regulate the crystallization of hydroxyapatite nanorods on PCPC. We found that these nanorods and the adsorbed BBR changed the interface micro-environment of PCPC by SEM images. The microenvironment of PCPC surface is essential for promoting BMSCs’ proliferation and differentiation. These results demonstrated that PCPC/BBR markedly improved the bone regeneration of osteoporosis rats. Moreover, PCPC/BBR had significantly increased the expression levels of ALP, osteocalcin and bone morphogenetic protein2 and RUNX2 in BMSCs originated from osteoporosis rats.