Symptomatic and silent cerebral ischemia (detected on MRI) in patients with type 2 diabetes mellitus after carotid revascularization procedures

Background: Type 2 diabetes mellitus (T2DM) is a significant independent risk factor for ischaemic stroke. Carotid revascularisation procedures are an effective method of primary and secondary stroke prevention. However, patients developed postoperative acute ischaemic lesions (AILs), which were identified via magnetic resonance imaging (MRI) of the brains. Most of the patients with these AILs lack clinically overt symptoms. Aims: To assess the risk of ischaemic brain damage in patients with T2DM in the setting of carotid angioplasty with stenting (CAS) or carotid endarterectomy (CAE). Materials and methods: This open prospective study comprised of 164 patients with carotid atherosclerosis, who have undergone either CAS or CAE. Patients with T2DM were included in Group 1: 38 patients and 28 patients with CAE. Group 2 included patients without T2DM: 62 patients with CAS and 36 patients with CAE. All patients underwent a thorough neurological examination and diffusion-weighted brain MRI. In patients with T2DM, plasma glucose levels and glycated haemoglobin (HbA1c) were determined and their relationships to brain damage were evaluated. Results: In CAS, there were no statistically significant differences in the AIL frequency in patients with and without T2DM. AILs were found in 15 patients with T2DM (39.8%) and 29 patients without T2DM (46.8%, р = 0.24); three patients without T2DM were diagnosed with stroke. Of the 28 patients with T2DM who underwent CAE, 13 had AIL (46.4%); three had stroke (10.7%). In patients without T2DM, AILs were less prevalent in seven cases (19.4%, р = 0.012) and appeared asymptomatic. Following CAS, the baseline HbA1c levels were higher in patients with T2DM who developed AILs compared to those who did not develop AIL, 7.8% ± 1.4% vs 7.1 ± 1.1% (р = 0.0469). Negative impact of hyperglycaemia on the risk of cerebral ischaemia was observed in patients who underwent CAE, the baseline fasting plasma glucose level was 8.5 ± 1.9 mmol/l vs 7.0 ± 1.5 mmol/l in patients without AIL (р = 0.014). The baseline HbA1c levels in patients with and without AILs were 8.0% ± 1.7% and 6.9% ± 0.9% respectively (р = 0.023). Conclusions: Carotid revascularisation procedure for patients with carotid atherosclerosis may be associated with risk of stroke and asymptomatic acute cerebral ischaemic lesions, which are more prevalent in patients with T2DM. Also, increased HbA1c levels is a risk factor for AIL

Navigated repetitive transcranial magnetic stimulation to correct eating behavior in obesity (clinical cases)

Obesity is a pathological condition caused by overweight and requiring medical intervention. The clinical and scientific experience gained over the past decades has allowed researchers to consider this problem as an independent disease with its own pathophysiological features, prevalence, incidence, approaches to therapy and prevention. One of the most important factors in the pathogenesis of obesity is disordered eating behavior, the central regulation of which is carried out with the active participation of the prefrontal cortex. Impact on this area (for example, using non-invasive brain stimulation) may be one of the promising ways to modulate eating behavior. The article describes clinical cases of treatment of morbid obesity using navigated rhythmic transcranial magnetic stimulation (rTMS). Different patterns of dorsolateral prefrontal cortex (DLPFC) activation before and after rTMS are demonstrated. Possible mechanisms of the influence of DLPFC on the formation of eating behavior are also considered. These data underline the important role of DLPFC dysregulation in obesity, as well as show potentially effective neuromodulation techniques

Neurological aspects of COVID-19

The novel coronavirus pandemic presents one of the most significant challenges to modern healthcare, which involves all medical specialties. The current review encompasses the neurologic manifestations of COVID-19 - a yet to be defined problem. L. Mao et al. (2020) have found a third of COVID-19 patients to exhibit neurological symptoms the latter divided into three categories: Central nervous system involvement (vertigo, headache, altered consciousness, acute cerebrovascular pathology, ataxia, and seizures) in 24.8% of patients, peripheral nervous system involvement (smell and taste disorders, neuropathy) - 8.9%, and muscle pathology (muscle pain, associated with creatine kinase increase) - 10,7%. Cerebrovascular pathology in 221 patients, described by Y. Li et al. (2020) occurred in 5.9% of cases - the majority was comprised by ischemic stroke, and as a whole it was associated with a more severe disease course. T. Oxley et al. (2020) described 5 patients (less than 50 years of age) with a large-vessel stroke occurring as a result of COVID-19. It has been shown that meningoencephalitis may be linked to COVID-19 - this review addresses several described cases. A case series of Guillain-Barré syndrome n patients with SARS-CoV-2 infection is also described. Apart from that, it is well established that COVID-19 may lead to deterioration of concurrent somatic and (or) neurological diseases, worsening the prognosis

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 p p 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 p 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

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 (p p 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

Type 2 diabetes mellitus and the clinical course of acute stroke

We carried out a comparative analysis of the clinical course of acute stroke in patients with and without type 2 diabetes mellitus (T2DM). The prevalence of carotid atherosclerosis (incl. those with plaques and hemodynamically significant [≥60%] carotid stenosis) was higher in patients with T2DM. With relatively similar baseline brain damage and neurological deficits patients with T2DM had a higher rate of symptom worsening, which leads to poorer outcome. A less favourable post-stroke prognosis was found to be associated with the presence of T2DM, but not with transient changes in glycemic levels. Most patients with T2DM presented with acute stroke showing elevated levels of both plasma glucose and glycated haemoglobin, the latter indicating a long period of hyperglycemia preceding the acute cerebrovascular event

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 −1, p p 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

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

Modern concepts of the pathogenesis of obesity and new approaches to its correction

The present review considers modern concepts of the physiological mechanisms of the formation of food behavior in a norm at several levels, beginning with the cellular level and ending with the level of functional systems. Neuroimaging methods used for both the study of the pathophysiological foundations of eating disorders and for determining the target for neurostimulation techniques are described. Methods of non-invasive brain stimulation such as transcranial magnetic stimulation and transcranial electrical stimulation, the mechanisms of their influence and aspects of safety of application are reviewed, the latest data on the results of studies on the use of the above methods in the therapy of obesity are summarized