bluuebunny/crossref_metadata_2025_split huggingface dataset:
Snipe: highly sensitive pathogen detection from metagenomic sequencing data
Authors: Huang Lihong , Hong Bin , Yang Wenxian , Wang Liansheng , Yu Rongshan 
Published: February 2021

Abstract
Metagenomics data provide rich information for the detection of foodborne pathogens from food and environmental samples that are mixed with complex background bacteria strains. While pathogen detection from metagenomic sequencing data has become an activity of increasing interest, shotgun sequencing of uncultured food samples typically produces data that contain reads from many different organisms, making accurate strain typing a challenging task. Particularly, as many pathogens may contain a common set of genes that are highly similar to those from normal bacteria in food samples, traditional strain-level abundance profiling approaches do not perform well at detecting pathogens of very low abundance levels. To overcome this limitation, we propose an abundance correction method based on species-specific genomic regions to achieve high sensitivity and high specificity in target pathogen detection at low abundance.
Morphometrical Brain Markers of Sex Difference
Authors: Brennan Daniel , Wu Tingting , Fan Jin 
Published: February 2021

Abstract
Many major neuropsychiatric pathologies, some of which appear in adolescence, show differentiated prevalence, onset, and symptomatology across the biological sexes. Therefore, mapping differences in brain structure between males and females during this critical developmental period may provide information about the neural mechanisms underlying the dimorphism of these pathologies. Utilizing a large dataset collected through the Adolescent Brain Cognitive Development study, we investigated the differences of adolescent (9–10 years old) male and female brains (n = 8325) by using a linear Support-Vector Machine Classifier to predict sex based on morphometry and image intensity values of structural brain imaging data. The classifier correctly classified the sex of 86% individuals with the insula, the precentral and postcentral gyri, and the pericallosal sulcus as the most discernable features. These results demonstrate the existence of complex, yet robustly measurable morphometrical brain markers of sex difference.
Provably Secure Online/Offline Identity-Based Signature Scheme Based on SM9
Authors: Lai Jianchang , Huang Xinyi , He Debiao , Wu Wei 
Published: February 2021

Abstract
SM9 is a Chinese cryptography standard, which includes a set of identity-based cryptographic schemes over pairings. SM9 identity-based signature scheme (SM9-IBS) was standardized by ISO/IEC and has been widely used in many real-world applications such as blockchain. Nevertheless, the signing algorithm of SM9-IBS suffers from several heavy calculations (e.g. pairings, scalar multiplications in groups), which might be a bottleneck for lightweight devices such as sensors. In this paper, we modify the SM9-IBS scheme slightly to support fast signing. In order to achieve this, we make the use of online/offline methodology and propose a new online/offline IBS scheme based on SM9. The proposed scheme is proved to be EUF-sID-CMA secure and is about 99% faster than SM9-IBS in terms of signature generation. Precisely, the time cost of online signing is &lt;1 ms. Our scheme is appropriate for the Internet of Things. The theoretical analysis and demonstration show that the proposed scheme is comparable to existing efficient online/offline IBS schemes.
Smart ultrasound device for real-time myocardial stiffness quantification of the human heart
Authors: Pedreira O , Papadacci C , Chatelin S , Correia M , Tanter M , Goudot G , Messas E , Pernot M 
Published: February 2021

Abstract

Funding Acknowledgements
Type of funding sources: Public grant(s) – EU funding. Main funding source(s): ERC

Introduction
Myocardial stiffness (MS) is crucial to understand cardiac biomechanics and evaluate cardiac function. We recently demonstrated that shear wave imaging using acoustic radiation force can provide quantitative end-diastolic MS in human patients [1] . However, the dependence of shear wave velocity with myofiber orientation remained a limitation and required to perform Shear Wave Velocity (SWV) estimations from different probe orientations which is challenging in clinical practice. We propose a new approach to provide real-time quantitative assessment of MS without dependence of the probe orientation based on a dedicated smart ultrasound (US) device.

Methods
A new US probe was designed and manufactured to generate acoustic radiation force along the central axis and track the SWV simultaneously along three different orientations to obtain an elliptic profile of SWS. The probe was connected to dedicated electronics and software to provide real-time end-diastolic MS with ECG gating. Validation was performed on 4 in-vitro calibrated phantoms (0.92 – 1.49 – 2.58 – 3.49 m/s) and on ex vivo porcine hearts. MS along and across the fibers were compared to the values measured by conventional shear wave imaging with a linear probe mounted on a rotation motor (angular step of 10°) (Aixplorer, Supersonic imaging). Finally, the in vivo feasibility and reproducibility of measuring MS of the antero-septal wall and of the right ventricular (RV) wall was assessed transthoracically on four human volunteer .

Results
In vitro results on phantoms showed a good agreement with calibrated value (r2 = 0.98, std = 4.8%). Elliptic profiles on ex-vivo porcine heart showed good agreement with Aixplorer measurements acquired at different angles, with a relative difference along the long axis (LA) of: Δ=7.0%, Δ=7.1%, Δ=9% respectively for left ventricle (LV), right ventricle (RV) and septum. Finally, myocardial SWV assessment in human volunteers was obtained successfully on the RV and on the septum in late diastole. The mean MS was 1.79+/- 0.15 m/s along the fiber direction, the fractional anisotropy (FA) was 0.25 +/- 0.06 on septal wall in good agreement with previous results [1] and 1.06 +/- 0.11 m/s along fibers orientation and a FA of 0.27 +/- 0.08 on RV. Finally the beat to beat reproducibility of MS measurement was estimated to be 8.22%.

Conclusion
The new smart US device allowed non-invasive quantification of anisotropic myocardial tissues in real time. Results showed the accuracy of the methods. This approach could offer a new clinical tool for the evaluation of the myocardium in cardiomyopathies and in heart failure patients.
Abstract Figure. SWV on myocardium human volonteer
Alterations in cardiac function in women with severe preeclampsia: return to normal in one year after delivery?
Authors: Ambrozic J , Lucovnik M , Cvijic M 
Published: February 2021

Abstract

Funding Acknowledgements
Type of funding sources: None.
Introduction. In peri-partum period women with preeclampsia have demonstrated signs of subtle left ventricular (LV) dysfunction. However, there is still controversy if these changes persist or improve late after delivery.
Purpose. To evaluate LV dimensions and function in severe preeclamptic women and healthy controls immediately post-delivery and 1 year postpartum.
Methods. The study population comprised 24 women with severe preeclampsia and 15 healthy term controls. All women underwent standard and speckle-tracking echocardiography to assess myocardial function and deformation parameters 1 day after delivery and 1 year postpartum. To examine the impact of preload and afterload on myocardial function LV end-diastolic volume and systolic blood pressure were used accordingly.
Results. On day 1 post-delivery women with severe preeclampsia were exposed to increased afterload with significantly higher systolic blood pressure compared to controls (147 [136-157] in preeclamptic vs. 112 [102-118] mmHg in control group, p &lt; 0.001). Similarly, preeclamptic women had also higher preload demonstrated with larger LV end-diastolic volume (114 [100-128] vs. 95 [92-102] ml, p = 0.003) and left atrial volume index (36 [33-38] vs. 32 [29-36] ml/m2, p = 0.02) than control group. Among other geometric parameters difference in LV mass index was observed between groups (preeclamptic group: (81 [70-96] vs. control group: 66 [61-74] g/m2, p = 0.01).
Global systolic parameters (LV ejection fraction and global longitudinal strain) did not differ between groups; however, peak systolic myocardial velocity (s’) was significantly lower in preeclamptic compared to control group (7.6 [6.5-8.1] vs. 8.0 [7.5-8.9] cm/s, p = 0.02) immediately post-delivery. Diastolic function differed between groups with significantly higher E/e’ ratio in preeclamptic women than controls (8.7 [7.6-10.0] vs. 6.9 [6.4-7.8] p = 0.01) one day post-delivery.
One year after delivery both groups had normal and similar arterial blood pressure and there were no differences in geometric, systolic and diastolic function parameters between groups (Figure A-D).
Conclusions. Our results showed that women with severe preeclampsia had subtle cardiac dysfunction immediately post-delivery compared to healthy controls and recovered completely in one year after delivery. Subtle cardiac dysfunction in preeclampsia immediately post-delivery seemed to be related or unmasked by pronounced changes in loading conditions, which resolved in mid-term postpartum period. Long-term follow-up with larger study population is needed to identify subgroup of women who have persistent subclinical cardiac alterations and experience cardiovascular events later in life.
Abstract Figure
Rest NT-proBNP but not MR-proANP predicts positive diastolic stress echocardiography test result in patients with preserved left ventricle ejection fraction and heart failure symptoms
Authors: Kubicius A , Balys M , Gasior Z , Haberka M 
Published: February 2021

Abstract

Funding Acknowledgements
Type of funding sources: Public Institution(s). Main funding source(s): Medical University of Silesia

Introduction
Diastolic dysfunction and heart failure (HF) with preserved ejection fraction are diagnostic challenges in rest transthoracic echocardiography (TTE) and clinical practice. The aim of our study was to evaluate the clinical value of diastolic stress echocardiography (DSE) and its corelation with NT-proBNP and MR-proANP testing in patients with preserved left ventricle ejection fraction (LVEF) and HF symptoms. Methods: All the consecutive patients with HF symptoms, preserved LVEF and suspected diastolic dysfunction were examined with DSE with the protocol according to the EACVI 2016 recommendations. Patients with cardiomyopahties, significant valve defects or extracardiac diseases causing similar symptoms were excluded. The assessment of diastolic function was obtained at rest transthoracic echocardiography (TTE) and at peak exertion in DSE: left atrium volume index (LAVI), average E/e’ &gt;14, peak tricuspid regurgitation velocity &gt;2,8 m/s, septal e’ velocity &lt;7 cm/s or lateral e’&lt; 10cm/s (&gt;50% positive – diastolic dysfunction). Moreover, blood samples for NT-proBNP and MR-proANP were taken just before and 30 minutes after DSE.

Results
The study group included 80 patients (age: 69 ± 8.3 years; 24% males) with dyspnea (NYHA IIa – 53pts; IIb – 17pts; III – 10pts) and risk factors: hypertension (77pts), diabetes (33pts), known coronary artery disease (8pts) and chronic kidney disease (21pts). The rest TTE showed preserved systolic function (LVEF 61.6 ± 8.8%) and normal or indeterminate diastolic function in all patients. DSE revealed positive result for diastolic dysfunction in 17 patients (21%). The levels of NT-proBNP :267(160-518) vs 310(172-522) (p = 0.46) and MR-proANP: 16,2(7,8-542) vs 14,7(6,1-646) p = 0,38 did not significantly change before and after DSE. The ROC analysis showed that age (AUC = 0.720; p &lt; 0.001), LAVI rest (AUC = 0.722, p &lt; 0.01), E/e’ rest (AUC 0.790;p &lt; 0.001) and baseline NT-proBNP (AUC 0.770; p = 0.002) predicted positive DSE. Other parameters, including BMI, baseline E/A, DT or e’ and MR-proANP were not predictive for DSE result. There was a positive correlation between stress NTproBNP and stress LAVI (r = 0.3;p &lt; 0.05) and stress E/e’ (r = 0.5; p &lt; 0.05) There wasn’t such correlation between MRproANP and stress LAVI and stress E/e’.

Conclusions
Diastolic stress echocardiography revealed diastolic dysfunction in 21% of study patients and improved the diagnostic value of echocardiography. Rest NT-proBNP but not rest MR-proANP predicted positive DSE.
Risk factors of persistent ventricular arrhythmias after mitral valve repair in Barlow disease patients: six-year follow-up
Authors: Malev E , Omelchenko M , Mitrofanova L , Gordeev M , Bondarenko B , Reeva S , Timofeev E 
Published: February 2021

Abstract

Funding Acknowledgements
Type of funding sources: None.

Introduction
Improvement in malignant ventricular arrhythmias (VA) has been reported after mitral valve surgery in some mitral valve prolapse patients (MVP) with severe degenerative mitral regurgitation. Mitral annular disjunction, posterior systolic curling, and mitral annular abnormal contractility are associated with arrhythmic MVP and underwent correction during the mitral valve repair. However, mitral valve disease progression and ventricular arrhythmic substrates (left ventricular fibrosis of papillary muscles and basal posterior wall) could be potential substrates for persistent malignant arrhythmias even after surgical correction.
Our aim was to evaluate the risk factors of persistent VA after mitral valve repair in Barlow’s disease patients in six-year follow-up.

Methods
30 consecutive patients (mean age 53.1 ± 9.4, 47% male) who underwent mitral valve repair for severe mitral regurgitation (MR) due to mitral valve prolapse were enrolled in our observational, prospective, single-center study. Resected abnormal segments of the mitral leaflets were examined by experienced pathologists for signs of myxomatous degeneration. Transthoracic echocardiography and 24-hour Holter monitoring were performed pre- and postoperatively annually. PVCs and nonsustained ventricular tachycardia (VT) runs were reviewed.

Results
All patients survived the operation. There was only one sudden cardiac death on sixth year of follow-up. During 173 person-years of follow-up 3 patients (10%) had developed recurrent moderate to severe (≥2) MR. The total number of PVCs and non-sustained ventricular tachycardia runs dropped significantly in 1st (p=.04, Wilcoxon matched pairs test) and 2nd (p=.03), years of postoperative follow-up.
Postoperative incidence of PVCs and VT correlated strongly with postoperative end-diastolic LV diameter (EDD rs=.69; p=.005), moderate negatively with LV ejection fraction (EF rs=-.55; p=.001).
Advanced myxomatous degeneration assessed by pathologists and MV posterior leaflet’s thickness ≥5 mm after repair assessed by echocardiographer associated with postoperative PVCs and VT (rτ=.58; p=.045 and rs=.62; p=.002, respectively). Recurrent MR also strongly associated with postoperative PVCs and VT (rs=.76; p=.0018).
In univariate analysis, advanced myxomatous degeneration (p=.008), postoperative end-diastolic LV diameter (p=.001), and low EF (p=.003) were identified as risk factors of persistent PVCs/VT after surgery.

Conclusions
Advanced myxomatous degeneration assessed by pathologists or echocardiographer and postoperative left ventricular remodeling are associated with persistent malignant ventricular arrhythmias. Further investigation in larger cohorts to evaluate the association between degenerative mitral valve disease and ventricular arrhythmias is needed.
Long-term outcome after transcatheter mitral annuloplasty for secondary mitral regurgitation
Authors: Lavall D , Bruns J , Stoebe S , Hagendorff A , Laufs U 
Published: February 2021

Abstract

Funding Acknowledgements
Type of funding sources: None.

Background
The long-term effects of transcatheter mitral valve annuloplasty (TMVA) for secondary mitral regurgitation is unknown.

Purpose
We studied the clinical outcome and the effects on left ventricular (LV) function and remodeling and on mitral regurgitation (MR) severity after TMVA using the Carillon annuloplasty device.

Methods
We analyzed 33 consecutive patients with symptomatic MR who were treated with TMVA at Leipzig University Hospital between 2012 and 2018. Echocardiography was performed before TMVA and at follow-up. MR severity was quantitatively assessed by regurgitant volume (calculated as LV total stroke volume – LV forward stroke volume) and regurgitant fraction (calculated as regurgitant volume / LV total stroke volume).

Results
Mean age was 80 ± 10 years, 19 patients were women. A Society of Thoracic Surgeons (STS) score of 8.1 ± 7.2% indicated high risk status for mitral valve surgery. In 26 patients, mitral regurgitation resulted from LV remodeling and LV dysfunction, 7 suffered from left atrial dilatation. LV ejection fraction at baseline was 38% (30-49%; median, interquartile range). During a mean follow-up time of 45 ± 20 months, 17 patients died, 2 patients withdraw consent, and 4 patients were lost. Of the remaining patients, 4 were hospitalized for decompensated heart failure, and 2 underwent additional transcatheter edge-to-edge mitral valve repair. At follow-up, NYHA functional class improved from 95% in class III/IV at baseline to 70% in class I/II with no patients in NYHA class IV (p &lt; 0.0001). Mitral regurgitant volume was reduced from 27mL (25-42mL) to 8mL (3-17mL) (p = 0.035) and regurgitant fraction from 43% (32-54%) to 11% (8-24%) (p = 0.020). LV end-diastolic volume index (92mL/m2 (71-107mL/m2) vs. 67mL/m2 (46-101mL/m2), p = 0.084) and end-systolic volumes index (51mL/m2 (44-69mL/m2) vs. 32mL/m2 (20-53mL/m2), p = 0.037) decreased. Thus, total stroke volume remained similar (38mL/m2 (33-43mL/m2) vs. 33mL/m2 (26-44mL/m2), p = 0.695) while LV ejection fraction increased (43% (31-49%) vs. 54% (46-57%), p = 0.032). Forward stroke volume, heart rate and forward cardiac output remained unchanged. Blood pressure was similar at baseline and at follow-up.
Conclusion. Among high risk patients undergoing transcatheter mitral valve annuloplasty for symptomatic secondary MR, mortality was about 50% at 4 years. In the surviving patients, reduced MR severity was associated with fewer heart failure symptoms, reverse LV remodeling and improved LV function.
Regurgitant volume to left ventricular end-diastolic volume ratio: another step to risk stratification in patients with secondary mitral regurgitation?
Authors: Lopes P , Albuquerque F , Freitas P , Horta E , Reis C , Abecasis J , Trabulo M , Ferreira A , Canada M , Ribeiras R , Mendes M , Andrade MJ 
Published: February 2021

Abstract

Funding Acknowledgements
Type of funding sources: None.

Background
Quantitative evaluation of secondary mitral valve regurgitation (MR) remains an important yet challenging step in the evaluation of this entity. Its severity can be underestimated when using the proximal isovelocity surface area (PISA) method, which does not take left ventricular (LV) volume into account. Normalizing mitral regurgitant volume (Rvol) for the LV end-diastolic volume (EDV) might overcome this key limitation. This study aimed to investigate the prognostic implication of Rvol/EDV ratio in patients with secondary MR.

Methods
Patients with at least mild secondary MR and reduced left ventricular ejection fraction (&lt;50%) under optimal guidelines-directed medical therapy were retrospectively identified at a single-center. The cohort was divided into terciles according to the RVol/EDV ratio. The primary endpoint was all-cause mortality.

Results
A total of 572 patients (median age 70 years; 76% male) were included. Median LVEF was 35% (IQR 28-40) and LVEDV was 169 ml (IQR 132-215). Median measures of secondary MR were EROA 14 mm2 (IQR 8-22) and RegVol 23 ml (12-34). During a median follow-up of 3.8 years (interquartile range 1.8 to 6.2 years) there were 254 deaths (44%). The unadjusted mortality incidence increases across terciles distribution. Patients at the 2nd and 3rd terciles of the RVol/EDV ratio showed significantly higher mortality when compared to those at the 1st one (baseline reference) (figure 1). After multivariable analysis, terciles of the Rvol/EDV ratio remained independently associated with increased all-cause mortality (considering the 1st tercile as the reference; adjusted HR for the 2nd tercile 1.46 [95% CI 1.05- 2.02] p = 0.023; adjusted HR for 3rd tercile 1.56 [95% CI 1.09 – 2.22], p = 0.015).

Conclusion
In patients with secondary MR, Rvol/EDV ratio is independently associated with all-cause mortality. However, the appropriate cut-off to determine any kind of clinical decision remains to be determined.
Abstract Figure.
Does age at aortic coarctation repair have an impact on left ventricle size and function?
Authors: Cardoso Torres S , Resende CX , Diogo PG , Araujo P , Pinto RA , Proenca T , Carvalho JM , Amador AF , Costa C , Calvao J , Ribeiro V , Cruz C , Macedo F 
Published: February 2021

Abstract

Funding Acknowledgements
Type of funding sources: None.

Introduction
Adults with repaired aortic coarctation (CoA) require lifelong follow-up due to late complications, including left ventricular (LV) myocardial dysfunction. Age at the time of CoA repair is an important prognostic factor in these patients (pts).

Purpose
To evaluate LV size, ejection fraction (EF) and global longitudinal strain (GLS) values using 2D speckle tracking echocardiography (STE) in a population of adult pts with repaired CoA and to assess the relationship between these echocardiographic parameters and age at the time of CoA repair.

Methods
Retrospective analysis of adult pts with repaired CoA, followed in a Grown Up Congenital Heart Disease Centre. Pts with hemodynamically significant concomitant cardiac lesions were ruled out. Epidemiologic and clinical data were obtained from clinical records. Transthoracic echocardiograms were reviewed in order to assess GLS using 2DSTE (Echopac Software, GE).

Results
The study population consisted of 63 pts (61.9% male), with a mean age of 35.3 years at the time of the echocardiographic evaluation. The mean age at the time of the CoA repair was 117 months (95% CI 89.8-144.1 months).
Surgical repair was performed in 46 pts (73%): resection with subclavian artery flap aortoplasty (n = 21); patch aortoplasty (n = 15) and head-to-head anastomosis (n = 10). In 10 pts there was no data regarding the type of surgical repair. Seven pts (11.1%) were submitted to percutaneous intervention (6 with aortic stent implantation and 1 with balloon aortic angioplasty).
Mean LVEF was 63.4% (CI 95% 55.6 – 71.2%) and mean LV end-diastolic diameter (LVEDD) was 50mm (CI 95% 43-57mm). Mean GLS was - 17.3 (CI 95% 14.8- 19.8), which is inferior to the mean normal values reported for the software used.
Age at the time of CoA repair had a statistically significant positive linear relationship with LVEDD (r= 0.282; p= 0.026) and a linear negative relationship with both GLS (r= -0,29; p= 0.022) and LVEF (r= -0.33; p= 0.05).

Conclusion
Older age at the time of CoA repair was associated with increased LVEDD and decreased GLS and LVEF. Also, GLS may be an important tool for the identification of subclinical LV dysfunction in adult pts with repaired CoA.