miR-33a and Its Association with Lipid Profile in Patients with Carotid Atherosclerosis.

Atherosclerosis is a chronic inflammatory disease with a complex, multifactorial pathogenesis, which includes lipid metabolism alterations. miR-33a is a microRNA that plays a key role in cholesterol efflux and promotes atherosclerosis, yet its relationship with lipid markers in carotid atherosclerosis (CA) remains unclear. The objective is to evaluate possible associations between miR-33a expression and lipid biomarkers in patients with CA. This was a prospective study that included 61 patients (median age 66.0 years, 55.7% male) with evidence of CA. Lipid profile (total cholesterol, triglycerides [TG], high-density lipoprotein [HDL] and low-density lipoprotein [LDL] cholesterol) was analyzed. Extraction and quantification of miR-33a-5p/3p was performed according to protocol. Patients were further divided depending on the target LDL level (<1.8 mmol/L). Patients with CA had relatively favorable LDL levels with a median of 2.0 mmol/L. Both miR-33a-5p and miR-33a-3p levels were lower in patients with less than targeted LDL levels (37.4 and 38.3 vs. 41.8 and 42.5 respectively, p < 0.05). A significant positive correlation between expression levels of miR-33a-5p/3p and degree of carotid stenosis was found (r = 0.44 and r = 0.38 respectively, p < 0.05). In a univariate linear regression model miR-33a-3p/5p was positively associated with LDL cholesterol (p = 0.02). miR-33a up-regulation is associated with CA and may, in fact, be a key player by targeting cholesterol metabolism. A decrease in LDL cholesterol (<1.8 mmol/L) corresponded to lower levels of miR-33a, yet the direction and causality of this association remains unclear.

MicroRNA and Hemostasis Profile of Carotid Atherosclerosis.

Carotid atherosclerosis (CA) is an important risk factor for ischemic stroke. We described the miRNA and hemostasis profile of patients with moderate and advanced stages of carotid atherosclerosis and elucidated potential correlations with hemostatic activation. A prospective case-control study included 61 patients with evidence of carotid atherosclerosis (via ultrasound). The study population was divided into groups depending on the degree of carotid artery stenosis: 60% or more (advanced) and <60% (moderate). All patients underwent the following blood tests: general blood test, hemostatic parameters and microRNA. Extraction of microRNA was performed using Leukocyte RNA Purification Kit (NORGEN Biotec Corp., Thorold, ON, Canada); miRNA quantification was performed via RT-PCR. Statistical analysis was performed in R programming language (v. 4.1.0) using RSudio. MicroRNA expression profile was different depending on CA degree. MiR-33a-5p/3p levels were higher in patients with ≥60% carotid stenosis (42.70 and 42.45 versus 38.50 and 38.50, respectively, p < 0.05). Almost complete separation can be visualized with the levels of miR-126-5p: 9.50 in the moderate CA group versus 5.25 in the advanced CA (p < 0.001). MiR-29-5p was higher in the moderate CA group: 28.60 [25.50;33.05] than in advanced CA group: 25.75 [24.38;29.50] (p = 0.086); miR-29-3p was also higher in the moderate CA group: 10.36 [8.60;14.99] than in advanced CA group: 8.46 [7.47;10.3] (p = 0.001). By-group pairwise correlation analyses revealed at least three clusters with significant positive correlations in the moderate CA group: miR-29-3p with factors V and XII (r = 0.53 and r = 0.37, respectively, p < 0.05); miR-21-5p with ADAMTS13, erythrocyte sedimentation rate and D-dimer (r = 0.42, r = 0.36 and r = 0.44, respectively, p < 0.05); stenosis degree with miR-33a-5p/3p and factor VIII levels (r = 0.43 (both) and r = 0.62, respectively, p < 0.05). Hemostasis parameters did not reveal significant changes in CA patients: the only statistically significant differences concerned factor VIII, plasminogen and (marginally significant) ADAMTS-13 and protein C. Down-regulation of miR-126-5p expression has been identified as a promising biomarker of advanced carotid atherosclerosis with high specificity and sensitivity. Correlation cluster analysis showed potential interplay between miRNAs and hemostatic activation in the setting of carotid atherosclerosis.

Red Blood Cell Morphodynamics in Patients with Polycythemia Vera and Stroke.

Polycythemia vera (PV) is a Ph-negative myeloproliferative neoplasm (MPN) which is characterized by erythrocytosis and a high incidence of thrombotic complications, including stroke. The study aimed to evaluate red blood cell (RBC) morphodynamic properties in PV patients and their possible association with stroke. We enrolled 48 patients with PV in this cross-sectional study, 13 of which have a history of ischemic stroke. The control group consisted of 90 healthy subjects. RBC deformability and aggregation analysis were performed using a laser-assisted optical rotational red cell analyzer. The following parameters were calculated: aggregation amplitude (Amp), RBC rouleaux formation time constant (Tf), time of formation of three-dimensional aggregates (Ts), aggregation index (AI), rate of complete disaggregation (y-dis), and the maximal elongation of RBC (EImax). Statistical analysis was performed with the R programming language. There were significant differences in RBCs morphodynamics features between patients with PV and the control group. Lower EImax (0.47 (0.44; 0.51) vs. 0.51 (0.47; 0.54), p < 0.001) and γ-dis (100 (100; 140) vs. 140 (106; 188) s-1, p < 0.001) along with higher amplitude (10.1 (8.6; 12.2) vs. 7.7 (6.6; 9.2), p < 0.001) was seen in patients with PV compared with control. A statistically significant difference between PV patients with and without stroke in aggregation amplitude was found (p = 0.03). A logistic regression model for stroke was built based on RBC morphodynamics which performed reasonably well (p = 0.01). RBC alterations may be associated with overt cerebrovascular disease in PV, suggesting a possible link between erythrocyte morphodynamics and increased risk of stroke.

Microrheological disorders in patients with polycythemia vera suffered acute ischemic stroke.

The relevance of the study is determined by the fact that the combination of cerebrovascular disorders and myeloproliferative diseases requires the search for a predictive biomarker to improve outcomes. The aim of this article was to explore the meanings of microrheological disorders in patients with polycythemia vera (PV) who suffered an acute ischemic stroke (AIS). The study was carried out at the Research center of Neurology. We studied microrheological properties in 181 patients (aged 42-75 years). From the AIS developed in 68 (38%) patients with PV; 59 (32%) patients with AIS were without PV; 54 (30%) patients with PV did not suffer AIS. Microrheological disorders, first of all, the red blood cells (RBC) deformability correlated to AIS severity and its features in comorbid patients. The RBC deformability was dependent on the allelic load of the V617F mutation in the JAK2 gene. Additionally, it was found that RBC deformability perform diagnostic value in the acute phase of ischemic stroke as well as get predictive value for thrombotic complications development within 2 years after AIS in such patients. We suppose that in patients with PV an ischemic stroke and thrombosis would directly depend on the success of PV treatment. In turn, RBC deformability is applicable for some predictive models to late thrombosis development.

Neuropoly: An Educational Board Game to Facilitate Neurology Learning.

Introduction: Neurology is arguably one of the most difficult subjects to teach and study in the medical curriculum. Educational games (EG) may be a valid option to enhance motivation in neurology residents. Methods: We developed an educational board game (Neuropoly) to assist in teaching neurology. We present here an overview of the game, as well as the results of a pilot study aimed at determining: (a) the efficacy of the game in teaching certain neurological concepts; and (b) student compliance and satisfaction with the EG. Results: The pre- and post-play questionnaire scores differed significantly (3.2 ± 1.7 vs. 7.8 ± 1.6, p < 0.001). Our group of residents, showing an overwhelmingly positive response, very well received the game. The questions were rated as above average regarding difficulty. Conclusion: The "Neuropoly" educational board game has been shown to be interesting, efficient, and motivational among first- and second-year neurology residents. Novel educational methods for complex medical disciplines should be developed, with board games being a viable and inexpensive approach.

Covert Brain Infarcts in Patients with Philadelphia Chromosome-Negative Myeloproliferative Disorders.

BACKGROUNDS AND PURPOSE: Philadelphia chromosome-negative myeloproliferative disorders (Ph-negative MPD) are a rare group of hematological diseases, including three distinct pathologies: essential thrombocythemia (ET), polycythemia vera (PV), and primary myelofibrosis (PMF). They most often manifest with thrombotic complications, including cerebrovascular events. Covert brain infarcts (CBIs) are defin ed as predominantly small ischemic cerebral lesions that are detected using magnetic resonance imaging (MRI) in the absence of clinical stroke events. The relationship between MPD and CBIs remains unclear. METHODS: Included in the study were 103 patients with the diagnosis of Ph-MPD (according to WHO 2016 criteria) (median age-47 (35; 54) years; 67% female). In total, 38 patients had ET, 42 had PV, and 23 had PMF. They underwent clinical examination, routine laboratory analyses (complete blood count), brain MRI, ultrasound carotid artery, flow-mediated dilatation (as a measure of endothelial dysfunction-FMD). RESULTS: Overall, 23 patients experienced an ischemic stroke (as per MRI and/or clinical history), of which 16 (15.5%) could be classified as CBIs. The rate of CBIs per MPD subtype was statistically non-significant between groups (p = 0.35): ET-13.2%, PV-21.4%, and PMF-8.7%. The major vascular risk factors, including arterial hypertension, carotid atherosclerosis, and prior venous thrombosis, were not associated with CBIs (p > 0.05). Age was significantly higher in patients with CBIs compared to patients without MRI ischemic lesions: 50 (43; 57) years vs. 36 (29; 48) (p = 0.002). The frequency of headaches was comparable between the two groups. CBIs were associated with endothelial dysfunction (OR - 0.71 (95% CI: 0.49-0.90; p = 0.02)) and higher hemoglobin levels (OR-1.21 (95% CI: 1.06-1.55); p =0.03). CONCLUSIONS: CBIs are common in patients with Ph-negative MPD. Arterial hypertension and carotid atherosclerosis were not associated with CBIs in this group of patients. The most significant factors in the development of CBIs were endothelial dysfunction (as measured by FMD) and high hemoglobin levels. Patients with Ph-negative MPD and CBIs were older and had more prevalent endothelial dysfunction.

Application of the genetic risk model for the analysis of predisposition to nonlacunar ischemic stroke.

Aim: The purpose of our study was to analyze the predictive ability of the multiplicative model of genetic risk of nonlacunar ischemic stroke (IS) for independent samples from Russia. Patients & methods: A total of 181 patients and 360 healthy controls were included in this study. The discriminative accuracy of model was evaluated by the area under the receiver operating characteristic curve (AUC). Results: Classification model based on 15 single-nucleotide polymorphisms (SNPs), which are associated with a cardioembolic subtype of IS, had an AUC of 0.62 in patients with corresponding subtypes and an AUC of 0.58 for all patients. Conclusion: Risk calculation approach based on IS-associated SNPs had satisfactory performance in predicting the predisposition to the disease.

Clinical Characteristics of Cerebrovascular Pathology with Patients Suffering from Ph-Negative Myeloproliferative Disease.

BACKGROUND: Disturbances of microcirculation play a significant role in the development and progression of both acute and chronic cerebrovascular diseases (CVD) and may be associated with different hemogram abnormalities. One of the reasons of the prothrombogenic state of the endothelium is the increase in the number of blood corpuscles leading to (non-Ph) myeloproliferative disorders (MPD) including essential thrombocythemia (ET), polycythemia vera (PV), and primary myelofibrosis (PM). MATERIALS AND METHODS: The study included 167 patients: 102 patients with Ph-MPD and the control group comprising 65 patients with CVD. According to MPD subtype, the patients were divided into three groups: patients with ET (37%, n = 38, male/female 7/31, age 52 ± 7 years), those with PV (40%, n = 41, male/female 20/21, age 50 ± 6 years) and those with PM (23%, n = 23, male/female 5/18, age 54 ± 4 years). RESULTS: In 79% (n = 81) of cases in the study group (with Ph-MPD), patients had chronic CVD, with the most frequently identified symptoms being asthenia (92%) and headache (72%). Headache in Ph-MPD patients was more frequently (86%) associated with PM, while in patients with PV and ET it was equally distributed (70%). Neurological symptoms in 53% of cases were associated with focal changes of the brain on MRI localized in the subcortical area of the frontal and parietal lobes. Twenty-one (21%) patients suffered an acute cerebrovascular accident, 8 of them had thrombotic occlusion of one of the internal carotid arteries leading to hemispheric infarcts. Endothelial function (as measured by flow-dependent dilation of the brachial artery) was severely impaired in all study groups (median 5% with normal cut-off at 10%), the lowest degree of vasodilator activity being specific for patients with a history of stroke (p = 0.011). CONCLUSION: Patients suffering from MPD had asymptomatic focal changes in the brain in the absence of concomitant vascular disease (hypertension, atherosclerotic vascular disease, heart rhythm disorders) in 50% of cases. MPD, while remaining un- or underdiagnosed, presents a major concern in the cerebrovascular setting. A large number of thrombotic strokes occurring in patients with ET underline the necessity of early diagnostics and preventive therapy in these patients.

New mutations in the Notch3 gene in patients with cerebral autosomal dominant arteriopathy with subcortical infarcts and leucoencephalopathy (CADASIL).

BACKGROUND: Cerebral autosomal dominant arteriopathy with subcortical infarcts and leucoencephalopathy (CADASIL) is a cerebrovascular small-vessel disease caused by stereotyped mutations in the Notch3 gene altering the number of cysteine residues. METHODS: We directly sequenced exons 2-23 of the Notch3 gene in 30 unrelated Russian patients with clinical/neuroimaging picture suggestive of CADASIL. To confirm the pathogenicity of new nucleotide variants, we used the standard bioinformatics tools and screened 200 ethnically matched individuals as controls. RESULTS: We identified 16 different point mutations in the Notch3 gene in 18 unrelated patients, including 4 new missense mutations (C194G, V252M, C338F, and C484G). All but two mutations affected the cysteine residue. The non-cysteine change V322M was shown to be associated with CADASIL-specific deposits of granular osmiophilic material in the vascular smooth-muscle cells, which confirmed the pathogenicity of this Notch3 variant. Two patients were shown to be compound-heterozygotes carrying two pathogenic Notch3 mutations. The disease was characterized by marked clinical variability, without evident phenotype-genotype correlations. CONCLUSIONS: In our sample, 60% of Russian patients with 'clinically suspected' CADASIL received the definitive molecularly proven diagnosis. Careful assessment of genealogical, clinical, and neuroimaging data in patients with lacunar stroke can help selecting patients with a high probability of finding mutations on genetic screening.