Post-covid-19 neurological syndromes

Treg Cells in Ischemic Stroke: A Small Key to a Great Orchestrion

Ischemic stroke is a global medical problem and one of the leading causes of death or disability worldwide. The main approach of ischemic stroke therapy in the most acute period, which can prevent or minimize the development of a neurological deficit, is the restoration of the blood flow in the ischemic brain tissue using enzymatic thrombolysis or endovascular thromboextraction. When the therapeutic window is missed, the modulation of the acute inflammatory response may play an important role in determining the fate of neurons in the penumbra. The key players in this process are T-regulatory cells (Tregs) an immunosuppressive population of CD4+ T-cells with the CD4+, CD25+ CD127low, FoxP3+ phenotype. Despite the existing reports that Tregs (or certain Treg subpopulations) can exacerbate microcirculatory disorders in the ischemic tissue, many stadies convincingly suggest the positive role of Tregs in ischemic stroke. Resident CD69+ Tregs found in the normal mammalian brain have neuroprotective activity, produce IL-10 and other anti-inflammatory cytokines, control astrogliosis, and downregulate cytotoxic subpopulations of T cells and microglia. Systemic administration of Treg in stroke is accompained by a decrease in the volume of cerebral infarction and decreased levels of secondary neuronal death. Thus, the methods allowing Treg activation and expansion ex vivo open up several new avenues for the immunocorrection not only in systemic and autoimmune diseases, but, potentially, in the neuroprotective therapy for ischemic stroke. The relationship between Treg, inflammation, and cerebrovascular pathology is of particular interest in the case of ischemic stroke and COVID-19 as a comorbidity. It has been demonstrated that systemic inflammation caused by SARS-CoV-2 infection leads to a significant suppression of Treg, which is accompanied by an increased risk for the development of ischemic stroke and other neurological complications. Overall, the information summarized herein about the possible therapeutic potential of Treg in cerebrovascular pathology may be of practical interest not only for researchers, but also for clinicians.

Comparative study of quality of life 9 months post-COVID-19 infection with SARS-CoV-2 of varying degrees of severity: impact of hospitalization vs. outpatient treatment

Purpose

This experimental study was conducted during the post-COVID-19 period to investigate the relationship between the quality of life 9 months after and the severity of the SARS-CoV-2 infection in two scenarios: hospitalization (with/without medical oxygen) and outpatient treatment.

Methods

We employed the EQ-5D-5L Quality of Life tests and the PSQI as a survey to evaluate respondents' quality of life 9 months after a previous SARS-CoV-2 infection of varying severity.

Results

We identified a clear difference in the quality of life of respondents, as measured on the 100-point scale of the EQ-5D-5L test, which was significantly lower 9 months after a previous SARS-CoV-2 infection for Group 1 (n = 14), respondents who had received medical attention for SARS-CoV-2 infection in a hospital with oxygen treatment, compared to those with the SARS-CoV-2 infection who were treated without oxygen treatment (Group 2) (n = 12) and those who were treated on an outpatient basis (Group 3) (n = 13) (H = 7.08 p = 0.029). There were no intergroup differences in quality of life indicators between hospitalized patients (Group 2) and groups 1 and 3. PSQI survey results showed that "mobility," "self-care," "daily activities," "pain/discomfort," and "anxiety/ depression" did not differ significantly between the groups, indicating that these factors were not associated with the severity of the SARS-CoV-2 infection. On the contrary, the respondents demonstrated significant inter-group differences (H = 7.51 p = 0.023) and the interdependence of respiratory difficulties with the severity of clinically diagnosed SARS-CoV-2 infection. This study also demonstrated significant differences in the values of sleep duration, sleep disorders, and daytime sleepiness indicators between the three groups of respondents, which indicate the influence of the severity of the infection. The PSQI test results revealed significant differences in "bedtime" (H = 6.00 p = 0.050) and "wake-up time" (H = 11.17 p = 0.004) between Groups 1 and 3 of respondents. At 9 months after COVID-19, respondents in Group 1 went to bed at a later time (pp = 0.02727) and woke up later (p = 0.003) than the respondents in Group 3.

Conclusion

This study is the first of its kind in the current literature to report on the quality of life of respondents 9 months after being diagnosed with COVID-19 and to draw comparisons between cohorts of hospitalized patients who were treated with medical oxygen vs. the cohorts of outpatient patients. The study's findings regarding post-COVID-19 quality of life indicators and their correlation with the severity of the SARS-CoV-2 infection can be used to categorize patients for targeted post-COVID-19 rehabilitation programs.

Morphological features of brain damage in severe COVID-19

Background: The damage to the nervous system in COVID-19 reflects the systemic nature of the infection. The question of the neuroinvasive potential of SARS-CoV-2 remains open, the role of "pseudovirions" in the development of the endothelial dysfunction, as well as of the S1 subunit in the TLR activation, and the importance of the blood-brain barrier are discussed. The immunological, non-immunological, and cytopathic mechanisms of the virus's action are described; there is no clear understanding of the genesis of neuropathological changes caused by SARS-CoV-2. In this tragic pandemic, the lessons of the dead should help save lives and health. Aim: to study and explain the features of brain damage in COVID-19. Methods: Brain fragments from 20 patients who died due to severe COVID-19 were studied, the sections were stained with hematoxylin and eosin, according to van Gieson and Nissl, IHC reactions were performed with antibodies to the S-protein, CD68 and CD8, the changes were compared with those related to the lethal outcomes of pancreatic necrosis and ruptured aortic aneurysm. Results: The following changes in the olfactory analyzer were revealed: sharp edema, dystrophic changes in neurons, gliosis, accumulations of starchy bodies, which explains the neuronal pathway of SARS-CoV-2 invasion; vascular plethora, erythrostasis and thrombosis, perivenular hemorrhages, diffuse edema, macroglia proliferation, perivascular astrocytosis and satellite. A positive reaction with the antibodies to the S1 and S2 subunits of the spike protein was detected, while the result of the reaction with antibodies to the N-protein of the virus, confirming the active replication of the virus, was doubtful. The S-protein expression in individual endotheliocytes makes the transendothelial route of the virus entry unlikely, in contrast to the hematogenous and neuronal pathways. The viral DNA was not detected by PCR. A weak inflammatory reaction was revealed in the form of perivascular accumulations of lymphocytes, scattered T-lymphocytes. Conclusions: 2 groups of changes were identified, the first group included circulatory disorders with a tendency to thrombosis, edema, dystrophic-necrotic changes in neurons, glial proliferation, the second group included inflammatory-degenerative changes, a weak inflammatory reaction and amyloid-like bodies. Further morphometric and statistical studies are needed to obtain the reliable conclusions.

[Medical rehabilitation features of patients suffered from new coronavirus infection]

Despite the development and implementation of preventive measures, new coronavirus infection (COVID-19) cases are still being registered among the population.

OBJECTIVE

To describe the methods of recovery treatment, used at different rehabilitation stages of patients suffered from COVID-19.

MATERIAL AND METHODS

An analytical review of rehabilitation methods of patients after COVID-19 was conducted. The literature reviews and original researches from Scopus, Web of Science, PubMed, CyberLeninka and eLibrary electronic databases were studied.

RESULTS AND CONCLUSION

Lungs, heart and vessels, gastrointestinal tract and central nervous system are most commonly affected by COVID-19. Due to this, the article considers key aspect of rehabilitation of patients with revealed disorders. Multidisciplinary approach is the main treatment type of patient with COVID-19. The effective result of comprehensive and multidisciplinary approach can be achieved only by the work of a team of specialists from different disciplines. The early onset, consistency and continuity of rehabilitation activities are important factors in the recovery of patients with post-COVID syndrome.

A rational strategy for the maintenance of antiviral immunity to new SARS-CoV-2 strains

New variants of SARS-CoV-2 such as Omicron BA.2, BA.4/5, BA.2.12.1 and BA 2.75 are characterized by higher infectivity and the ability to escape virus-neutralizing antibodies against previous coronavirus variants. The S-trimer of BA.2 and its phylogenetic derivatives are characterized by a predominant Up-conformation, which facilitates the interaction with ACE2 on target cells and promotes the resistance to neutralizing antibodies. The immunity acquired from the infection with earlier strains is non-sterile for both early and later strains; the booster systemic immunization does not significantly affect the effectiveness of antiviral immunity, and its feasibility is currently being questioned. Studies of the mucosal immune response have shown that intranasal immunization with adenovirus vaccines provides more pronounced protective immunity than systemic reimmunization does. A promising approach is the creation of multivalent inhaled next generation vaccines containing immunoadjuvants that activate B- and T-cell mucosal immunity. Currently, a large number of intranasal vaccines are undergoing phase I/II trials, while the preclinical and preliminary clinical results indicate that this method of vaccination provides a better mucosal immune response at the entry site of the virus than systemic immunization does. This strategy may provide a long-term immune protection against the currently existing and yet unknown new strains of SARS-CoV-2.