Radiomic Phenotype of Periatrial Adipose Tissue in the Prognosis of Late Postablation Recurrence of Idiopathic Atrial Fibrillation.

The aim of the study is to find new predictors of postablation atrial fibrillation (AF) recurrence in patients with lone AF using a texture analysis of the periatrial adipose tissue (PAAT) of the left atrium. Materials and Methods: Forty-three patients admitted for lone AF catheter ablation, who had undergone multispiral coronary angiography, were enrolled in the study. PAAT segmentation was performed using 3D Slicer application followed by extraction of 93 radiomic features. At the end of the follow-up period, patients were divided into 2 groups depending on the presence or absence of AF recurrence. Results: 12 months of follow-up after catheter ablation, postablation AF recurrence was reported in 19 out of 43 patients. Of 93 extracted radiomic features of PAAT, statistically significant differences were observed for 3 features of the Gray Level Size Zone matrix. At the same time, only one radiomic feature of PAAT, Size Zone Non Uniformity Normalized, was an independent predictor of postablative recurrence of AF after catheter ablation and 12 months of follow-up (McFadden's R2=0.451, OR - 0.506, 95% CI: 0.331‒0.776, p<0.001). Conclusion: The radiomic analysis of periatrial adipose tissue may be considered as a promising non-invasive method for predicting adverse outcomes of the catheter treatment, which opens the possibilities for planning and correction of patient management tactics after intervention.

Subacute myocardial infarction detected by technetium-99m-labeled somatostatin analog scintigraphy.

Recently, the applicability of somatostatin receptor-targeted (SSTR-t) radiotracers for post-ischemic myocardial inflammation imaging has been shown using PET. Currently, there are no studies which demonstrate ability of SPECT and technetium-99m SSTR-t radiotracers to detect inflammation, which appears in response to acute myocardial infarction (AMI). A case of 51-year-old male with acute anterior myocardial infarction (AMI) with ST elevation has been presented. This patient on 7th day after AMI onset underwent SPECT/CT (by cardiac cadmium-zinc-telluride gamma-camera) with 99mTc-Tectrotide, cardiac MRI with gadolinium and, on 9th day after AMI, myocardial perfusion scintigraphy (MPS) at rest. Clear myocardial uptake of 99mTc-Tectrotide, predominantly in apical and intermediate anterior wall of left ventricle was detected. The uptake matched with areas of hypoperfusion (by SPECT) and myocardial injury (by MRI). This case demonstrated the applicability of technetium-99m-labeled SSTR-t radiotracers for post-infarction inflammation imaging. Currently assumed, that SSTR-t radiotracers reflect an increased number of activated macrophages infiltrating infarcted myocardium, which is not possible using any other imaging technique. Thus, potentially, SSTR scintigraphy may be useful for diagnosis and monitoring of myocardial post-infarction inflammation as well as for anti-inflammatory image-guide therapy assessment.

A simplified cluster model and a tool adapted for collaborative labeling of lung cancer CT scans.

BACKGROUND AND OBJECTIVE: Lung cancer is the most common type of cancer with a high mortality rate. Early detection using medical imaging is critically important for the long-term survival of the patients. Computer-aided diagnosis (CAD) tools can potentially reduce the number of incorrect interpretations of medical image data by radiologists. Datasets with adequate sample size, annotation, and truth are the dominant factors in developing and training effective CAD algorithms. The objective of this study was to produce a practical approach and a tool for the creation of medical image datasets. METHODS: The proposed model uses the modified maximum transverse diameter approach to mark a putative lung nodule. The modification involves the possibility to use a set of overlapping spheres of appropriate size to approximate the shape of the nodule. The algorithm embedded in the model also groups the marks made by different readers for the same lesion. We used the data of 536 randomly selected patients of Moscow outpatient clinics to create a dataset of standard-dose chest computed tomography (CT) scans utilizing the double-reading approach with arbitration. Six volunteer radiologists independently produced a report for each scan using the proposed model with the main focus on the detection of lesions with sizes ranging from 3 to 30 mm. After this, an arbitrator reviewed their marks and annotations. RESULTS: The maximum transverse diameter approach outperformed the alternative methods (3D box, ellipsoid, and complete outline construction) in a study of 10,000 computer-generated tumor models of different shapes in terms of accuracy and speed of nodule shape approximation. The markup and annotation of the CTLungCa-500 dataset revealed 72 studies containing no lung nodules. The remaining 464 CT scans contained 3151 lesions marked by at least one radiologist: 56%, 14%, and 29% of the lesions were malignant, benign, and non-nodular, respectively. 2887 lesions have the target size of 3-30 mm. Only 70 nodules were uniformly identified by all the six readers. An increase in the number of independent readers providing CT scans interpretations led to an accuracy increase associated with a decrease in agreement. The dataset markup process took three working weeks. CONCLUSIONS: The developed cluster model simplifies the collaborative and crowdsourced creation of image repositories and makes it time-efficient. Our proof-of-concept dataset provides a valuable source of annotated medical imaging data for training CAD algorithms aimed at early detection of lung nodules. The tool and the dataset are publicly available at https://github.com/Center-of-Diagnostics-and-Telemedicine/FAnTom.git and https://mosmed.ai/en/datasets/ct_lungcancer_500/, respectively.

Deglycosylation of apo B-containing lipoproteins increase their ability to aggregate and to promote intracellular cholesterol accumulation in vitro.

Sub-fractions of all apo B-100 containing lipoproteins (low density lipoproteins, very low density lipoproteins and intermediate density lipoproteins) with reduced contents of sialic acid were found in vivo in human blood. These lipoproteins were inclined to spontaneously form aggregates and were able to stimulate accumulation of cholesterol in cells cultured from human aortic intima. In vitro treatment of apo B-containing lipoproteins with 2,6- and 2,3-specific sialidases, alpha-mannosidase, endoglycosidases F1 or F2 or peptide-N-glycanase F also stimulated aggregation and increased the ability of these particles to potentiate cholesterol accumulation in cells of the intact human aortic intima. So, deglycosylation of various apo B-containing lipoproteins possibly occurs in the blood, decreases their resistance to aggregation and increases the ability of these particles to stimulate accumulation of cholesterol in human aortic intima cells, thereby increasing their atherogenic potential.

[Comparison of systemic manifestations of inflammation in torpid pulmonary tuberculosis and respiratory sarcoidosis].

The authors determined acute-phase protein spectrum, monocytic and neutrophilic functions by the values of spontaneous and stimulated HCT-tests, platelet function under basal conditions and their varying stimulation, the state of the hemostatic system, and the parameters of intravascular blood coagulation in 66 patients with torpid pulmonary tuberculosis and 84 patients with respiratory sarcoidosis (RS). The changes found in both diseases were fundamentally unilateral; however, they were more frequently detected in RS and they were more pronounced. In tuberculosis, all detected changes may give the impression that they are secondary to tuberculous infection and, in RS, act as primary triggers in the development ofgranulomatous inflammation.

Desialylation decreases the resistance of apo B-containing lipoproteins to aggregation and increases their atherogenic potential.

Subfractions of apo B-containing lipoproteins (VLDL and intermediate-density lipoproteins) with reduced content of sialic acid were found in human blood. These lipoproteins are characterized by high capacity to spontaneous association (aggregation) and stimulated accumulation of cholesterol in smooth muscle cells of human aortic intima. In vitro treatment of apo B-containing lipoproteins with alpha-2,6-sialidase and alpha-2,3-sialidase stimulated aggregation and increased the ability of these particles to potentiate cholesterol accumulation in smooth muscle cells of the intact human aortic intima. Probably, desialylation of various apo B-containing lipoproteins can occur in the blood; this process decreases their resistance to aggregation, and increases the ability of these particles to stimulate accumulation of cholesterol in human aortic intima cells, i.e. increases their atherogenic potential.

[Atypical and unfavorable variants in the course of sarcoidosis]. / Atipichnye i neblagopriiatnye varianty techeniia sarkoidoza.

Sarcoidosis with atypical clinical manifestations and a poor course accounts for 5.6% (78 individuals per 1400 patients). The paper describes the atypical manifestations of sarcoidosis (fever, hypereosinophilia, lymphocytosis, etc.) and its poor course, which are similar to those of lymphoproliferative diseases, fibrosing alveolitis-type sarcoidosis, infiltrative pneumonic forms). Each of the above manifestations has complex differentially diagnostic aspects.

[Modification of the lipid membrane matrix with magnesium]. / Modifikatsiia magneziei lipidnogo matriksa membrany.

The influence of sulphuric magnesium on the molecular regulation processes in lecithin-water systems was investigated by the optical methods of polarized microscopy, refractometry and infrared spectroscopy. The obtained changes of structure parameters are interpreted by the modification role of Mg2+ cations and SO4(2-) groups.