Coronary microthrombi in the failing human heart: the role of von Willebrand factor and PECAM-1

The recognition of microthrombi in the heart microcirculation has recently emerged from studies in COVID-19 decedents. The present study investigated the ultrastructure of coronary microthrombi in heart failure (HF) due to cardiomyopathies that are unrelated to COVID-19 infection. In addition, we have investigated the role of von Willebrand factor (VWF) and PECAM-1 in microthrombus formation. We used electron microscopy to investigate the occurrence of microthrombi in patients with HF due to dilated (DCM, n = 7), inflammatory (MYO, n = 6) and ischemic (ICM, n = 7) cardiomyopathy and 4 control patients. VWF and PECAM-1 was studied by quantitative immunohistochemistry and Western blot. In comparison to control, the number of microthrombi was increased 7-9 times in HF. This was associated with a 3.5-fold increase in the number of Weibel-Palade bodies (WPb) in DCM and MYO compared to control. A fivefold increase in WPb in ICM was significantly different from control, DCM and MYO. In Western blot, VWF was increased twofold in DCM and MYO, and more than threefold in ICM. The difference between ICM and DCM and MYO was statistically significant. These results were confirmed by quantitative immunohistochemistry. Compared to control, PECAM-1 was by approximatively threefold increased in all groups of patients. This is the first study to demonstrate the occurrence of microthrombi in the failing human heart. The occurrence of microthrombi is associated with increased expression of VWF and the number of WPb, being more pronounced in ICM. These changes are likely not compensated by increases in PECAM-1 expression.

Atrial fibrillation in human patients is associated with increased collagen type V and TGFbeta1

Background and aim

Atrial fibrosis is an important factor in initiating and maintaining atrial fibrillation (AF). Collagen V belongs to fibrillar collagens. There are, however no data on collagen V in AF. The aim of this work was to study the quantity of collagen V and its relationship with the number of fibroblasts and TGF- b 1 expression in patients in sinus rhythm (SR) and in patients with atrial fibrillation (AF).

Methods

We used quantitative immuhistochemistry to study collagen V in right and left atrial biopsies obtained from 35 patients in SR, 35 patients with paroxysmal AF (pAF) and 27 patients with chronic, long-standing persistent AF (cAF). In addition, we have quantified the number of vimentin-positive fibroblasts and expression levels of TGF-β1.

Results

Compared to patients in SR, collagen V was increased 1.8- and 3.1-fold in patients with pAF and cAF, respectively. In comparison with SR patients, the number of vimentin-positive cells increased significantly 1.46- and 1.8-fold in pAF and cAF patients, respectively.Compared to SR patients, expression levels of TGF-ß1, expressed as fluorescence units per tissue area, was significantly increased by 77 % and 300 % in patients with pAF and cAF, respectively. Similar to intensity measurements, the number of TGFß1-positive cells per 1 mm2 atrial tissue increased significantly from 35.5 ± 5.5 cells in SR patients to 61.9 ± 12.4 cells in pAF and 131.5 ± 23.5 cells in cAF. In both types of measurements, there was a statistically significant difference between pAF and cAF groups.

Conclusions

This is the first study to show that AF is associated with increased expression levels of collagen V and TGF-ß1indicating its role in the pathogenesis of atrial fibrosis. In addition, increases in collagen V correlate with increased number of fibroblasts and TGF-β1 and are more pronounced in cAF patients than those in pAF patients.

Association of plasma propionate concentration with coronary artery disease in a large cross-sectional study

Background

Microbiome has been linked to the pathogenesis of coronary artery disease (CAD) but data providing direct evidence for an association of short-chain fatty acids (SCFA) with CAD are lacking. This study aimed to evaluate the role of propionate, the most important SCFA in patients with CAD.

Methods

We performed a cross-sectional study enrolling patients admitted for invasive coronary angiography in two university hospitals in Germany. Patients with known or suspected CAD and risk factors for cardiovascular disease were prospectively recruited. Blood sampling was performed after overnight fasting and before invasive procedures. Measurement of propionate was performed by liquid chromatography.

Results

The study included 1,253 patients (median [IQR], 67 [58-76] years; 799 men [64%]). A total of 739 had invasively confirmed CAD with at least one coronary artery stenosis ≥50% and 514 had exclusion of CAD. CAD patients had significant lower levels of propionate (median 5.75 μM, IQR, 4.1-7.6) compared to the non-CAD groups 6.53 μM (4.6-8.6, p < 0.001). Multivariate linear regression analysis revealed an odds ratio of 0.94 (CI 0.90-0.98, p = 0.002) for propionate as predictor of CAD. The odds ratio was further decreased to 0.45 (CI 0.31-0.65, p < 0.001) when comparing patients in the lowest quartile of propionate with those with higher levels of propionate.

Conclusion

The study provides large-scale in vivo data for the association of propionate to manifest coronary artery disease, independent of other traditional cardiovascular risk factors.

Detecting the sources of chemicals in the Black Sea using non-target screening and deep learning convolutional neural networks

The Black Sea is an important ecosystem, which is affected by various anthropogenic pressures, such as shipping activities and wastewater inputs from large coastal cities. Significant loads of chemical pollutants are being continuously brought in by major European rivers. This study investigated the spatial distribution of chemicals in the Ukrainian shelf (the northwestern part of the Black Sea) and their main sources. Chemical occurrence data used in the study was generated within the Joint Black Sea Surveys (JBSS), which took place in 2016 and 2017 as a part of the EU/UNDP EMBLAS II project (www.emblasproject.org). During the JBSS, seawater samples were analyzed by a non-target screening workflow using liquid chromatography high-resolution mass spectrometry (LC-HRMS). Open-source algorithms were applied to generate a combined dataset of 30,489 detected chemical signals and their intensities. Out of these, 35 compounds were tentatively identified by the application of a non-target screening identification workflow based on automated matching of their mass spectra against those in available mass spectral libraries. The dataset was used to generate images, representing spatial distribution of each of the signals. These images were then used as an input to a deep learning convolutional neural network classification model. The study resulted in the development of an open-source end-to-end workflow for the estimation of the pollution load by chemicals contributed by the two major inflowing rivers (Danube and Dnieper) and other, so far unidentified, sources. A dedicated dashboard was built to facilitate data visualization per detected signal/compound. The presented model proved to be especially useful at the prioritization of signals of unknown compounds, which is of key importance for the follow up structure elucidation efforts of bulky non-target screening data. The deep learning approach for peak prioritization of unknown chemicals in the environment has been used for the first time.

Recognizing Emotional States Using Speech Information

Emotion recognition plays an important role in several applications, such as human computer interaction and understanding affective state of users in certain tasks, e.g., within a learning process, monitoring of elderly, interactive entertainment etc. It may be based upon several modalities, e.g., by analyzing facial expressions and/or speech, using electroencephalograms, electrocardiograms etc. In certain applications the only available modality is the user's (speaker's) voice. In this paper we aim to analyze speakers' emotions based solely on paralinguistic information, i.e., not depending on the linguistic aspect of speech. We compare two machine learning approaches, namely a Convolutional Neural Network and a Support Vector Machine. The former is trained using raw speech information, while the latter is trained on a set of extracted low-level features. Aiming to provide a multilingual approach, training and testing datasets contain speech from different languages.

pyAudioAnalysis: An Open-Source Python Library for Audio Signal Analysis

Audio information plays a rather important role in the increasing digital content that is available today, resulting in a need for methodologies that automatically analyze such content: audio event recognition for home automations and surveillance systems, speech recognition, music information retrieval, multimodal analysis (e.g. audio-visual analysis of online videos for content-based recommendation), etc. This paper presents pyAudioAnalysis, an open-source Python library that provides a wide range of audio analysis procedures including: feature extraction, classification of audio signals, supervised and unsupervised segmentation and content visualization. pyAudioAnalysis is licensed under the Apache License and is available at GitHub (https://github.com/tyiannak/pyAudioAnalysis/). Here we present the theoretical background behind the wide range of the implemented methodologies, along with evaluation metrics for some of the methods. pyAudioAnalysis has been already used in several audio analysis research applications: smart-home functionalities through audio event detection, speech emotion recognition, depression classification based on audio-visual features, music segmentation, multimodal content-based movie recommendation and health applications (e.g. monitoring eating habits). The feedback provided from all these particular audio applications has led to practical enhancement of the library.

A Low Cost Pupillometry Approach

The need for low-cost health monitoring is increasing with the continuous increase of the elderly population. In this context, unobtrusive audiovisual monitoring methods can be of great importance. More particularly, the diameter of the pupil is a valuable source of information, since, apart from pathological cases, it can reveal the emotional state, the fatigue and the ageing. To allow for unobtrusive monitoring to gain acceptance, one should seek for efficient methods of monitoring using common low-cost hardware. This paper describes a method for monitoring pupil sizes using a common, low-cost web camera in real time. The proposed approach detects the face and the eyes area at first stage. Subsequently, optimal iris and sclera location and radius, modeled as ellipses, are found using efficient spatial filtering. As a final step, the pupil center and radius is estimated by optimal filtering within the area of the iris. Experimental results show both the efficiency and the effectiveness of our approach.

Endostaples: are they the solution to graft migration and Type I endoleaks?

Effective proximal sealing, especially in the long-term, remains a limitation of contemporary endovascular aortic aneurysm repair (EVAR). Endostaples that fixate the proximal stent-graft to the aortic neck wall, aiming for better apposition and proximal sealing have been recently introduced in clinical practice to address this problem. Initial experimental studies have shown that endostaples can increase proximal stent-graft fixation to levels equivalent or superior to that of a hand-sewn anastomosis. Further clinical studies aimed to investigate whether this increased proximal fixation results in reduced migration and better sealing with lower rates of type I endoleak. The present chapter discusses the efficacy of endostaples in reducing migration and type I endoleak after EVAR, based on published clinical data.

Vascular surgery training and its relationship to other surgical specialties

During the last 50 years vascular surgery has met an enormous evolution, paving the way for the development of modern vascular and endovascular surgery. Although, vascular surgery (VS) has emerged from general (GS) and cardiothoracic surgery (CTS), the need for specialized training has been recognized and gradually practice patterns are shifting towards vascular independence, but yet not in all countries. In these countries VS training is either permitted only after prerequisite GS certification, or as a non accredited surgical specialty, VS might be included in GS or CTS training and certification. Such a policy raises two main issues: the efficiency of vascular training within the GS or CTS curricula and the performance of vascular interventions by general or cardiothoracic surgeons. Meanwhile, the explosion of endovascular procedures has brought new disciplines into play, each one wanting to maintain its stake in the future. Interventional radiologists and a significant number of cardiologists become increasingly involved in the treatment of vascular diseases. The question of which specialist among those qualified should carry out medical treatment, open, and endovascular procedures is still suspended. Under this prism, vascular training issues arise as an important component of the future of vascular surgeons.

Current knowledge on E-vita abdominal endograft

The field of endovascular abdominal aortic repair has changed remarkably compared to what it was prior to 1993, the year of the first commercial endograft deployment in the United States. Over the years of endovascular aneurysm repair experience, various companies have attempted to construct an ideal stent-graft for exclusion of an abdominal aortic aneurysm (AAA). However, it has become evident that not all abdominal aortic anatomies are amenable to endovascular treatment and that the rationale "one device fits all AAAs" can lead to disastrous results. Different endografts have dissimilar properties and characteristics. Type of graft material, configuration and type of stent structural support, modularity, type of transrenal fixation, are potentially influential factors of endograft behavior. The self-expanding E-vita abdominal stent-graft (JOTEC, Hechingen, Germany) is a relatively new infrarenal, modular stent-graft with suprarenal fixation designed for AAA reconstruction. The present paper analyzes the technical characteristics and properties of this device. We also analyze our experience with the endoprosthesis and review the current literature.

Urgent CAS for patients in high neurologic risk

Patients with residual carotid stenosis discovered following an acute ischemic insult represent a new subset of patients eligible for early carotid intervention that may decrease the risk of recurrent stroke by new emboli and improve cerebral blood flow. Short-term clinical outcomes of patients undergoing urgent CAS appear favorable, indicating that endovascular management may be a reasonable treatment option, particularly when combined with endovascular interventions for intracranial lesions. Data on indication and complication profiles are still limited. This review focuses on current knowledge, advantages and pitfalls of urgent and/or early (up to 2 weeks) carotid stenting in those presenting with an acute neurologic event or recently symptomatic carotid stenosis.