bluuebunny/crossref_metadata_2025_split huggingface dataset:
Preparation and properties of MDA-BAPP-BTDA copolyimide/18-crown ether-6 supramolecular films with inclusion structure and ultralow dielectric constants
Authors: Xiao Chunguang , Li Duxin , Lang Feng , Xiang Yu , Lin Yi , Ou Baoli 
Published: July 2021

Abstract
In order to obtain polyimide composites with ultra-low dielectric constant, a series of MDA-BAPP-BTDA copolyimides/18-crown ether-6 (CPI/18-CE) supramolecular films with inclusion structure were prepared. The effects of 18-CE on CPI’s thermal, mechanical, dielectric and water absorption properties were investigated. The inclusion rate of 18-CE to CPI backbone was ∼50%. The introduction of 18-CE slightly reduced the thermal properties of CPI/18-CE supramolecular films, but greatly improved their mechanical, dielectric and hydrophobic properties. The tensile strength, young’s modulus and elongation at break of CPI/18-CE supramolecular films were maximally increased by 21.8%, 34.1% and 92.9% respectively. Meanwhile their dielectric constant, dielectric loss and water absorption were as low as 2.10, 0.007 and 0.63%, respectively. In summary, CPI/18-CE supramolecular films possess excellent dielectric properties and broad application prospect in the field of microelectronics.
SPOT: a web-tool enabling swift profiling of transcriptomes
Authors: Farr Elias B , Sattler Julia M , Frischknecht Friedrich 
Published: July 2021

Abstract

The increasing number of single cell and bulk RNAseq datasets describing complex gene expression profiles in different organisms, organs or cell types calls for an intuitive tool allowing rapid comparative analysis. Here, we present Swift Profiling Of Transcriptomes (SPOT) as a web tool that allows not only differential expression analysis but also fast ranking of genes fitting transcription profiles of interest. Based on a heuristic approach the spot algorithm ranks the genes according to their proximity to the user-defined gene expression profile of interest. The best hits are visualized as a table, bar chart or dot plot and can be exported as an Excel file. While the tool is generally applicable, we tested it on RNAseq data from malaria parasites that undergo multiple stage transformations during their complex life cycle as well as on data from multiple human organs during development and cell lines infected by SARS-CoV-2. SPOT should enable non-bioinformaticians to easily analyse their own and any available dataset.

Availability and implementation
SPOT is freely available for (academic) use at: https://frischknechtlab.shinyapps.io/SPOT/ and https://github.com/EliasFarr/SPOT.

Supplementary information
Supplementary data are available at Bioinformatics online.
Systematic reporting of medical kidney biopsies
Authors: Leh Sabine , Dendooven Amélie 
Published: July 2021

ABSTRACT
The medical kidney biopsy has an important added value in patient care in nephrology. In order to facilitate communication between the pathologist and the nephrologist and optimize patient care, both the content and form of the medical kidney biopsy report matter. With some exceptions, current guidelines in nephropathology focus on content rather than form and, not surprisingly, medical kidney biopsy reports mostly consist of unformatted and often lengthy free text. In contrast, in oncology, a more systematic reporting called synoptic reporting has become the dominant method. Synoptic formats enable complete, concise and clear reports that comply with agreed upon standards. In this review we discuss the possibilities of systematic reporting in nephropathology (including synoptic reporting). Furthermore, we explore applications of electronic formats with structured data and usage of international terminologies or coding systems. The benefits include the timely collection of high-quality data for benchmarking between centres as well as for epidemiologic and other research studies. Based on these developments, a scenario for future medical kidney biopsy reporting is drafted.
Orientation of the right superior pulmonary vein affects outcome after pulmonary vein isolation
Authors: Vecsey-Nagy M , Szegedi N , Simon J , Szilveszter B , Kolossvary M , Boussoussou M , Vattay B , Delgado V , Jeroen B , Maurovich-Horvat P , Merkely B , Geller L 
Published: July 2021

Abstract

Funding Acknowledgements
Type of funding sources: None.

Aims
Controversial results have been published regarding the influence of pulmonary vein (PV) anatomical variations on outcomes after pulmonary vein isolation (PVI). However, no data is available on the impact of PV orientation on the long-term success rates of point-by-point PVI. We sought to determine the impact of PV anatomy and orientation on atrial fibrillation (AF)-free survival in patients undergoing PVI using the radiofrequency point-by-point technique.

Methods and results
We retrospectively included 448 patients who underwent initial point-by-point radiofrequency ablation for AF at our department. Left atrial CT-angiography (CTA) was performed before each procedure. PV anatomical variations, ostial parameters (area, effective diameter and eccentricity), orientation and their associations with 24-month AF-free survival were analyzed. PV anatomical variations and ostial parameters were not predictive for AF-free survival (all p &gt; 0.05). Univariate analysis showed that female sex (p = 0.025) was associated with higher rates of AF recurrence, ventral-caudal (p = 0.002), dorsal-cranial (p = 0.034) and dorsal-caudal (p = 0.042) orientation of the right superior PV (RSPV), on the other hand, showed an association with lower rates of AF recurrence, as compared to the reference ventral-cranial orientation. On multivariate analysis, both female sex [odds ratio(OR) 1.83, 95% CI 1.15-2.93, p = 0.011] and ventral-caudal RSPV orientation, compared with ventral-cranial orientation, proved to be independent predictors of 24-month AF recurrence (OR 0.37, 95% CI 0.19-0.71, p = 0.003).

Conclusion
Female sex and ventral-caudal RSPV orientation have an impact on long-term arrhythmia-free survival. Assessment of PV orientation may be a useful tool in predicting AF-free survival and may contribute to a more personalized management of AF.
Characterization of apolipoprotein E-deficient rats as novel model for atherosclerosis imaging
Authors: Sijbesma JWA , Van Waarde A , Kristensen S , Kion I , Tietge UJF , Hillebrands JL , Buikema H , Nakladal D , Liu F , Boersma HH , Dierckx RAJO , Slart RHJA 
Published: July 2021

Abstract

Funding Acknowledgements
Type of funding sources: None.

Background
The apolipoprotein E-deficient (apoE-/-) mouse is a well-established atherosclerotic model with impaired lipoprotein clearance and development of vessel plaques. However, the small size of the mouse limits its use as an animal model in longitudinal positron emission tomography (PET) imaging studies of atherosclerosis. Recently, apoE-/- rats have become available. This study addresses the suitability of the apoE-/- rat as model for atherosclerotic PET imaging.

Methods
Ten male apoE-/- rats and ten male control rats (apoE+/+) (age 10+/-1 weeks), each fed with a Western diet, were injected at baseline week 4, 12, 26 and 51, with 60 MBq of [18F]2-fluoro-2-deoxy-D-glucose. Plasma cholesterol, body weight and fat were measured. 3h after injection, a computed tomography (CT) and a 20-min PET scan were made. After the final scan, aortic tissue was collected for histological staining.

Results
Cholesterol levels started to increase after 4 weeks in the apoE-/- rats, whereas in the apoE+/+ rats levels stayed stable. Body weight and body fat increased more rapidly in the apoE-/- rats but were similar in both strains at the end of the study. SUVmean and max in the aortic arch and abdominal aorta were significantly higher (p &lt; 0.001) in apoE-/- versus apoE+/+ rats at weeks 12, 26 and 51. Oil red O staining showed lesions in 20.0 % of the surface of the aortic arch in the apoE-/- rats. Hardly no fatty streaks were detected in the apoE+/+ rats (2.29%). More histology data is being analyzed.

Conclusion
Plasma cholesterol levels were elevated in apoE-/- rats. PET imaging demonstrated differences in [18F]-FDG uptake in the aortic arch and abdominal aorta after 12, 26 and 51 weeks. Combined, these data demonstrate that apoE-/- rats represent a useful preclinical model for the non-invasive assessment of atherosclerosis in longitudinal studies.
Inter-operator reliability of an onsite machine learning-based prototype to estimate CT angiography-derived fractional flow reserve
Authors: Han Y , Ahmed AI , Schwemmer C , Cocker M , Alnabelsi T , Ramirez-Giraldo JC , Al Rifai M , Nabi F , Chang SM , Al-Mallah MH 
Published: July 2021

Abstract

Funding Acknowledgements
Type of funding sources: None.

Background
Advances in computed tomography (CT) and machine learning have enabled on-site non-invasive assessment of fractional flow reserve (ML-FFRCT). However, reproducibility of measurements across operators is not well demonstrated.

Purpose
This study was designed to measure the inter-operator variability and reproducibility of Coronary CT Angiography–derived fractional flow reserve values using a post-processing prototype based on a machine learning algorithm (ML-FFRCT).

Methods
We included 60 symptomatic patients who underwent coronary CT angiography. FFRCT was calculated by 2 independent operators after training using a machine learning based on-site prototype. FFRCT was measured 1 cm distal to the coronary plaque or in the middle of the segments if no coronary lesions were present. Intraclass correlation coefficient (ICC) and Bland-Altman analysis were used to evaluate inter-operator variability effect in FFRCT estimates. Sensitivity analysis was done by cardiac risk factors, degree of stenosis and image quality.

Results
A total of 535 coronary segments in 60 patients were assessed. The overall ICC was 0.986 per patient (95% CI: 0.977 - 0.992) and 0.972 per segment (95% CI: 0.967 - 0.977). The absolute mean difference in FFRCT estimates was 0.012 per patient (95% CI for limits of agreement: -0.035 - 0.039) and 0.02 per segment (95% CI for limits of agreement: -0.077 - 0.080). Tight limits of agreement were seen on Bland-Altman analysis. Distal segments had greater variability compared to proximal/mid segments (absolute mean difference 0.011 vs 0.025, p &lt; 0.001). Sensitivity analysis showed similar results across degrees of stenosis, image quality and those with cardiac risk factors such as hypertension, diabetes and dyslipidemia.

Conclusion
A high degree of inter-operator reproducibility can be achieved by onsite machine learning based ML-FFRCT assessment. Future research is required to evaluate the physiological relevance and prognostic value of ML-FFRCT.
Stress only myocardial perfusion imaging - comparison of hospitalized and outpatient patients
Authors: Stalc M , Dolenc Novak M , Saric S , Strojnik M , Guzic Salobir B 
Published: July 2021

Abstract

Funding Acknowledgements
Type of funding sources: None.

Background
In selected patients, stress-only myocardial perfusion imaging (MPI) has been proposed as an alternative to rest-stress MPI to reduce radiation exposure and enhance laboratory efficiency. The use of attenuation correction improves the diagnostic accuracy of stress-only imaging. However, criteria for selecting appropriate patients for stress-first imaging protocol are not uniform. There is limited data about stress-only MPI in hospitalized patients.
The purpose of this study was to compare the proportion of suitable hospitalized and outpatient patients with normal MPI on a routine two-day protocol for stress-only MPI.

Methods
In a retrospective longitudinal cohort study, stress scintigrams (with and without attenuation correction) of consecutive hospitalized and outpatient patients who underwent MPI at our department by a routine two-day protocol and had a normal MPI were visually and semi-quantitatively re-examined. Patients with summed stress score 0 or 1 were considered as candidates for stress-only MPI. We also obtained data on the patients" clinical characteristics and their treatment.

Results
We studied 178 patients (mean age 68.8 ± 13.4 years, 89 hospitalized, 89 outpatient patients, 55.6 % female). Hospitalized patients were significantly older than outpatient participants (72.4 ± 13.0 vs. 65 ± 12.9 years, p &lt; 0.001) with no significant differences in risk factors and clinical characteristics. Proportion of inpatients and outpatients suitable for stress-only MPI with and without attenuation correction is shown on Figure 1. There was no significant difference in stress-only MPI with and without attenuation correction between hospitalized and outpatient patients (Figure 1). 9.1% of patients in whom stress only MPI was possible had known coronary artery disease, whereas it was present in 25.0% of patients in whom stress-only MPI was not possible (p = 0.004). By using attenuation correction stress-only MPI could be performed in 54% of patients without known coronary artery disease. There was no difference between hospitalized patients and outpatients (52% vs. 56%, p = 0.700). Absence of coronary artery disease turned out as the only independent prognostic factor for application of stress-only MPI (odds ratio 3.433, 95% confidence interval 1.44-8.17, p = 0.003). There was no influence of hospitalization on the application of stress-only MPI.

Conclusions
When we choose the right patients (especially those without a known coronary artery disease) and use modern cameras that enable attenuation correction, we can perform stress-only MPI in 50% of patients with a normal MPI result. The same approach can be used for outpatients and inpatients.
INOCA: Unraveling the pathophysiological mechanisms, non-invasively
Authors: Gobbo MY , Meretta AH , Sciancalepore MA , Rosa D , Corneli M , Blanco N , Retamozo E , Beber E , Coronel DS , Perez Balino NA , Masoli OH 
Published: July 2021

Abstract

Funding Acknowledgements
Type of funding sources: None.

Introduction
INOCA syndrome (Ischemia with Non-Obstructive Coronary Arteries) is an increasingly frequent finding. One of the proposed causes is microvascular dysfunction (MVD). CZT-SPECT systems quantifies myocardial blood flow (MBF) during rest and after hyperemia. Dipyridamole induced hyperemia is considered endothelium independent whereas cold pressor test (CPT) endothelium dependent. Using both stimuli vasomotor response of endothelium can be evaluated through the analysis of MBF relationship (MBFR): MBF during induced hyperemia/MBF rest.

Objectives
To determine the prevalence of microvascular dysfunction in patients with INOCA, through the analysis of non-invasive evaluation MBFR with dipyridamole and CPT.

Methods
Dynamic and myocardial perfusion imaging at rest, after dipyridamole (0,56 mg/kg i.v. in 4 minutes) and CPT (hand immersion during 2 minutes in 4ºC cold water) were performed in 45 patients with INOCA history of using CZT-SPECT system.
A MBFR less than 2 was considered abnormal to dipyridamole induced hyperemia and less than 1.5 to CPT induced hyperemia.
The presence of an abnormal dipyridamole or CPT MBFR was considered as MVD.

Patients with MVD were divided into two groups
Group 1: normal dipyridamole MBFR and abnormal CPT MBFR.
Group 2: abnormal dipyridamole MBFR and abnormal CPT MBFR.
Comparison between variables were made with Wilcoxon signed rank test.

Results
The median age was 59 (32-78) years. Thirty-two patients (71%) were women and the majority (n = 29) were in the menopausal period. The cardiovascular risk factors present were: type 2 diabetes mellitus (n = 4), arterial hypertension (n = 21), smoking (n = 18) and dyslipidemia (n = 25).
All patients had normal myocardial perfusion at rest and with both stresses.
Thirty-nine patients (87%) presented MVD, 24 (54%) were in the group 1 and 15 (33%) in group 2. (Table 1)

Conclusion
The prevalence of MVD was 87 % in patients with INOCA.The use of both stresses made it possible to evaluate different pathophysiological mechanisms of MVD, dependent on smooth muscle and dependent on the endothelium.
Evaluation with CPT should be included in INOCA patients because MVD may be present even with preserved MBFR using dipyridamole.
Scintigraphic and echocardiographic evaluation of patients with cardiac transthyretin amyloidosis and first-degree relatives
Authors: Holcman K , Rubis P , Szot W , Graczyk K , Stepien A , Lesniak-Sobelga A , Hlawaty M , Wisniowska-Smialek S , Dziewiecka E , Karabinowska A , Mroz K , Podolec P , Kostkiewicz M 
Published: July 2021

Abstract

Funding Acknowledgements
Type of funding sources: Other. Main funding source(s): Pfizer Research Grant (ID#57165999)

Background
Misfolding of transthyretin (TTR) is the source of two distinct forms of amyloidosis (ATTR): acquired or wild-type (ATTRwt) and hereditary (ATTRm), which is transmitted in an autosomal dominant inheritance with a variable penetrance. Types of transthyretin (TTR) gene mutations display genetic and ethnic variability.

Purpose
The aim of this prospective study was to assess the TTR gene variants, echocardiographic parameters and regional left ventricle 99mTc-DPD uptake among patients with ATTR and first-degree relatives.

Methods
We present data based on evaluation of first 25 patients (13 (52%) females), including 10 (40%) index patients with ATTR (age 66.4 ± 13 years) and 15 (60%) first-degree relatives who were studied between June 2020 and February 2021. Analysis included clinical data, free light chain blood immunoglobulins and urine immunofixation, transthoracic echocardiography (TTE) with global longitudinal strain (GLS) analysis, single-photon emission computed tomography (SPECT) with 3,3-disphono-1,2-propanodicarboxylic acid (DPD), genetic testing by an amplicon-based next-generation TTR sequencing approach, and in selected cases cardiac or soft tissue biopsy.

Results
Overall, 6 index patients were diagnosed with ATTRm and 4 with ATTRwt presenting mixed, cardiac or neuropathic phenotype. There were detected following types of TTR variants - Phe53Leu, Ala101Val, Glu112Lys, Glu109Lys. Nine out of 10 index patients were diagnosed with amyloid cardiomyopathy (CA) with grade 2-3 tracer uptake in SPECT and symptomatic heart failure (NYHA 2.2 ± 1.1; NT-proBNP value 2224 ± 2799 pg/ml). In both ATTRm and ATTRwt there were patients presenting with either focal or diffuse tracer pattern evaluated by SPECT technique. In TTE there was marked left ventricle (LV) hypertrophy with maximum wall thickness of 22 ± 5 mm and LV mass value index value of 382 ± 111 g/m2. All patients with CA had abnormal global longitudinal strain (GLS, -14.5 ± 5%) and diastolic dysfunction (EA 1.56 ± 0.76, E/E’ 16 ± 11). None of relatives expressed tracer uptake in scintigraphy. Overall, 5 first-degree relatives were diagnosed with Phe53Leu variant, among them two patients presented with decreased GLS value.

Conclusions
Patients with ATTR presented in TTE with LV hypertrophy, decreased GLS value, diastolic dysfunction and grade 2-3 in scintigraphy with either focal or diffuse tracer uptake in SPECT technique. None of first-degree relatives expressed increased tracer uptake in scintigraphy. However, some of relatives who were diagnosed with pathogenic TTR variant presented with decreased GLS value.
A 7-year warranty period for chest pain patients with a non-ischaemic [15O]H2O positron emission tomography: a follow-up of 273 individuals
Authors: Jukema RA , Diemen Van PA , Driessen RS , Stuijfzand J , Raijmakers PG , Winter De RW , Ven Van De PM , Rossum Van AC , Knaapen P , Danad I 
Published: July 2021

Abstract

Funding Acknowledgements
Type of funding sources: None.

Background
A normal perfusion scan is associated with a favourable outcome. The aim of the present study is to determine the warranty period of normal hyperemic myocardial blood flow (MBF) derived with quantitative [15O]H2O positron emission tomography (PET) in symptomatic individuals with cardiovascular risk factors.

Methods
A total of 539 patients referred for baseline adenosine [15O]H2O PET MBF imaging because of suspected coronary artery disease (CAD) were investigated. A PET scan was considered normal if the hyperemic MBF was &gt; 2.3 ml/min/g. The warranty period was predefined as &lt; 2% annual event rate. The primary endpoint was a composite of late revascularizations, myocardial infarction and all-cause mortality.

Results
In a total of 273 patients (mean age 57.2 ± 9.1; 34.4% male) with a normal PET scan, 19 events occurred during a median follow-up of 6.8 years (interquartile range 4.9-7.7). Events included 10 late revascularizations, 2 myocardial infarctions and 7 deaths. The annual event rate exceeded 2% in the 8th year of follow-up, resulting in a warranty period of 7 years (see Figure 1).

Conclusion
In patients referred for suspected CAD a normal hyperemic perfusion derived by [15O]H2O PET confers a 7-year warranty period against late revascularization, myocardial infarction and all-cause mortality.
[18F]FDG hypermetabolisms of the spleen and/or bone marrow: indirect signs of bacteremia
Authors: Zanca R , Bartoli F , Lazzeri E , Sollini M , Slart RHJA , Erba PA 
Published: July 2021

Abstract

Funding Acknowledgements
Type of funding sources: None.

Aim
Recently hypermetabolisms of the spleen and/or bone marrow has been proposed as an indirect sign of infective endocarditis (IE), useful to reinforce the suspicion of IE in the absence of any other infectious, inflammatory, or malignant disease. The purpose of this study is to determine whether hypermetabolisms of the spleen and/or bone marrow are indirect signs of bacteremia rather than of IE, specifically.

Materials and Method
In this work we retrospectively evaluated a series 240 patients who performed between January 2015 to December 2020 [18F]FDG PET/CT (Discovery 710 GE) for suspected infection. In particular, 80 pts had infections from different origin and a positive blood culture (PBC), 80 pts presented localized infection, but negative blood culture (IDBCN) and 80 pts were classified as definite IE (IED) according to the 2015 ESCcriteria. [18F]FDG SUVmax SUVmean in bone marrow, spleen and liver were measured drawind a 14 cm3 regions of interest (ROIs) positioned close to the centers of the spleen and of the right liver lobe, but excluding abscess and/or ischemic lesions., as previously described (Caroline Boursier et al. ; Jordy P.Pijl et al.). BM SUVmax and SUVmean was obtained from ROIs placed on the bodies of each of the five lumbar vertebrae, excluding any damaged vertebra. BM to liver SUV ratios (BLR) and spleen to liver SUV ratios (SLR) were calculated. Kruskal-Wallis tests and the Dunn’s test procedure for multiple comparison were performed using JMP Statistical Discoverytm.

Results
No significant difference among the three groups of SUVmax/mean or in SLR were found. Nevertheless, by grouping patients for the presence of positive blood culture (142 pts) or negative blood culture (98 pts), irrespectively from the final diagnosis a significant associations of SLR was found (p = 0.0070). No significant associations were found with BLR.

Conclusions
Based on our data SLR in seems to represent an indirect signs of bacteremia, rather than IE.