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Could an acute respiratory distress syndrome in COVID-19 infected patients be calmed down simply by iron withdrawal from lung tissues?
No full textAnalytical features of the SIR model and their applications to COVID-19
No full textA classic two-parameter epidemiological SIR-model of the coronavirus propagation is considered. The first integrals of the system of non-linear equations are obtained. The Painlevé test shows that the system of equations is not integrable in the general case. However, the general solution is obtained in quadrature as an inverse time-function. Using the first integrals of the system of equations, analytical dependencies for the number of infected patients I(t) and that of recovered patients R(t) on the number of susceptible to infection S(t) are obtained. A particular attention is paid to interrelation of I(t) and R(t) both depending on α/β, where α is the contact rate in the community and β is the intensity of recovery/decease of patients. It is demonstrated that the data on particular morbidity waves in Hubei (China), Italy, Austria, South Korea, Moscow (Russia) as well some Australian territories are satisfactorily described by the expressions obtained for I(R). The variability of parameter N having been traditionally considered as a static population size is discussed
First-passage problem for stochastic differential equations with combined parametric Gaussian and Lévy white noises via path integral method
No full textWe study the first-passage problem for a process governed by a stochastic differential equation (SDE) driven simultaneously by both parametric Gaussian and Lévy white noises. We extend the path integral (PI) method to solve the SDE with this combined noise input and the corresponding fractional Fokker-Planck-Kolmogorov equations. Then, the PI solutions are modified to analyze the first-passage problem. Finally, numerical examples based on Monte Carlo simulations verify the extension of the PI method and the modification of the PI solutions. The detailed effects of the system parameters on the first-passage problem are analyzed
Impact of renin-angiotensin system inhibitors on mortality during the COVID Pandemic among STEMI patients undergoing mechanical reperfusion: Insight from an international STEMI registry
No full textBackground: Concerns have been raised on a potential interaction between renin-angiotensin system inhibitors (RASI) and the susceptibility to coronavirus disease 2019 (COVID-19). No data have been so far reported on the prognostic impact of RASI in patients suffering from ST-elevation myocardial infarction (STEMI) during COVID-19 pandemic, which was the aim of the present study. Methods: STEMI patients treated with primary percutaneous coronary intervention (PPCI) and enrolled in the ISACS-STEMI COVID-19 registry were included in the present sub-analysis and divided according to RASI therapy at admission. Results: Our population is represented by 6095 patients, of whom 3654 admitted in 2019 and 2441 in 2020. No difference in the prevalence of SARSCoV2 infection was observed according to RASI therapy at admission (2.5% vs 2.1%, p = 0.5), which was associated with a significantly lower mortality (adjusted OR [95% CI]=0.68 [0.51–0.90], P = 0.006), confirmed in the analysis restricted to 2020 (adjusted OR [95% CI]=0.5[0.33–0.74], P = 0.001). Among the 5388 patients in whom data on in-hospital medication were available, in-hospital RASI therapy was associated with a significantly lower mortality (2.1% vs 16.7%, OR [95% CI]=0.11 [0.084–0.14], p < 0.0001), confirmed after adjustment in both periods. Among the 62 SARSCoV-2 positive patients, RASI therapy, both at admission or in-hospital, showed no prognostic effect. Conclusions: This is the first study to investigate the impact of RASI therapy on the prognosis and SARSCoV2 infection of STEMI patients undergoing PPCI during the COVID-19 pandemic. Both pre-admission and in-hospital RASI were associated with lower mortality. Among SARSCoV2-positive patients, both chronic and in-hospital RASI therapy showed no impact on survival
Media Influence on Anxiety, Health Utility, and Health Beliefs Early in the SARS-CoV-2 Pandemic—a Survey Study
No full textBackground: The psychological effects from the COVID-19 pandemic and response are poorly understood. Objective: To understand the effects of the pandemic and response on anxiety and health utility in a nationally representative sample of US adults. Design: A de-identified, cross-sectional survey was administered at the end of April 2020. Probability weights were assigned using estimates from the 2018 American Community Survey and Integrated Public Use Microdata Series Estimates. Participants: US adults 18–85 years of age with landline, texting-enabled cellphone, or internet access. Intervention: Seven split-half survey blocks of 30 questions, assessing demographics, COVID-19-related health attitudes, and standardized measures of generalized self-efficacy, anxiety, depression, personality, and generic health utility. Main Measures: State/Trait anxiety scores, EQ-5D-3L Visual Analog Scale (VAS) score, and demographic predictors of these scores. Key Results: Among 4855 respondents, 56.7% checked COVID-19-related news several times daily, and 84.4% at least once daily. Only 65.7% desired SARS-CoV-2 vaccination for themselves, and 70.1% for their child. Mean state anxiety (S-anxiety) score was significantly higher than mean trait anxiety (T-anxiety) score (44.9, 95%CI 43.5–46.3 vs. 41.6, 95%CI 38.7–44.5; p = 0.03), with both scores significantly higher than previously published norms. In an adjusted regression model, less frequent news viewing was associated with significantly lower S-anxiety score. Mean EQ-5D-3L VAS score for the population was significantly lower vs. established US normative data (71.4 CI 67.4–75.5, std. error 2 vs. societal mean 80, std. error 0.1; p < 0.001). EQ-5D-3L VAS score was bimodal (highest with hourly and no viewing) and significantly reduced with less media viewership in an adjusted model. Conclusions: Among a nationally representative sample, there were higher S-anxiety and lower EQ-5D-3L VAS scores compared to non-pandemic normative data, indicative of a potential detrimental acute effect of the pandemic. More frequent daily media viewership was significantly associated with higher S-anxiety but also predictive of higher health utility, as measured by EQ-5D-3L VAS scores
COVID-19 in Russia: Clinical and Immunological Features of the First-Wave Patients
No full textThe coronavirus disease outbreak in 2019 (COVID-19) has now achieved the level of a global pandemic and affected more than 100 million people on all five continents and caused over 2 million deaths. Russia is, needless to say, among the countries affected by SARS-CoV-2, and its health authorities have mobilized significant efforts and resources to fight the disease. The paper presents the result of a functional analysis of 155 patients in the Moscow Region who were examined at the Central Clinical Hospital of the Russian Academy of Sciences during the first wave of the pandemic (February–July, 2020). The inclusion criteria were a positive PCR test and typical, computed tomographic findings of viral pneumonia in the form of ground-glass opacities. A clinical correlation analysis was performed in four groups of patients: (1) those who were not on mechanical ventilation, (2) those who were on mechanical ventilation, and (3) those who subsequently recovered or (4) died. The correlation analysis also considered confounding comorbidities (diabetes, metabolic syndrome, hypertension, etc.). The immunological status of the patients was examined (levels of immunoglobulins of the M, A, G classes and their subclasses, as well as the total immunoglobulin level) using an original SARS-CoV-2 antibody ELISA kit. The ELISA kit was developed using linear S-protein RBD-SD1 and NTD fragments, as well as the N-protein, as antigens. These antigens were produced in the prokaryotic E. coli system. Recombinant RBD produced in the eukaryotic CHO system (RBD CHO) was used as an antigen representing conformational RBD epitopes. The immunoglobulin A level was found to be the earliest serological criterion for the development of a SARS-CoV-2 infection and it yielded the best sensitivity and diagnostic significance of ELISA compared to that of class M immunoglobulin. We demonstrated that the seroconversion rate of “early” N-protein-specific IgM and IgA antibodies is comparable to that of antibodies specific to RBD conformational epitopes. At the same time, seroconversion of SARS-CoV-2 N-protein-specific class G immunoglobulins was significantly faster compared to that of other specific antibodies. Our findings suggest that the strong immunogenicity of the RBD fragment is for the most part associated with its conformational epitopes, while the linear RBD and NTD epitopes have the least immunogenicity. An analysis of the occurrence rate of SARS-CoV-2-specific immunoglobulins of different classes revealed that RBD-and N-specific antibodies should be evaluated in parallel to improve the sensitivity of ELISA. An analysis of the immunoglobulin subclass distribution in sera of seropositive patients revealed uniform induction of N-protein-specific IgG subclasses G1–G4 and IgA subclasses A1–A2 in groups of patients with varying severity of COVID-19. In the case of the S-protein, G1, G3, and A1 were the main subclasses of antibodies involved in the immune response
The balance between two branches of ras can protect from severe COVID-19 course
No full textThe COVID-19 pandemic has spread all over the world and required the mobilization of the efforts of scientists and doctors to develop new methods of treatment this serious disease. Along with research of the SARS- C6V-2 virology, understanding of the fundamental physiological processes, molecular cell mechanisms and intracellular signaling pathways underlying the clinical manifestations of COVID-19 is important for the rational design of effective therapy. The review describes in details the interaction of the components of the renin-angiotensin system (RAS) and receptor for advanced glycation end products (RAGE), which plays a special role in normal lung physiology and pathology in COVID-19, up to the development of acute respiratory distress syndrome and cytokine storm. A separate section presents modern approaches for correcting RAS dysfunction caused by binding the virus to angiotensin converting enzyme 2(ACE2), a central component of this system. Analysis of published theoretical, clinical, and experimental data suggests the need for complex treatment to prevent severe COVID-19 course using MasR agonists, blockers of AT1R and NF-κB signaling pathway, as well as compounds with neuroprotective and regenerative effects
Modern opportunities of interferons in treatment of children with COVID-19
No full textIntroduction. In 2020, most doctors were at the frontlines in the fight against the novel coronavirus infection (COVID-19). In the process of searching for effective etiotropic drugs, news came in that type I interferons had been successfully used for the treatment of COVID-19. Choosing the optimal COVID-19 treatment strategy is of pivotal importance for vulnerable populations such as children. Objective of the study. To show our own experience in providing medical care to children with COVID-19 and present the results of a comparative study of the efficacy and safety of interferon alfa-2b drugs combined with highly active antioxidants in the complex COVID-19 therapy in children. Materials and methods. A comparative study of the efficacy and safety of interferon alfa-2b drugs combined with highly active antioxidants in the complex COVID-19 therapy in children was conducted. The study included children with a laboratoryconfirmed diagnosis of COVID-19 aged 1 - 17 years (n = 85). In the treatment group (n = 45), children received interferon alfa-2b drugs such as VIFERON® rectal suppositories and VIFERON® gel for topical administration according to the dosage regimen and standard therapy. In the control group (n = 40), children only received standard therapy in accordance with the recommendations of the Ministry of Health of Russia. Results and discussion. 3,696 patients, including 3,507 children, received medical care in the City Children’s Hospital No. 1 in Kazan since April 2020. The share of laboratory-confirmed COVID-19 cases among admitted children was 21% (n = 736), of which 85 were enrolled in the study to assess the efficacy of complex therapy with interferon alpha-2b drugs combined with highly active antioxidants. The interferon alfa-2b therapy of COVID-19 children reduced the duration of the key clinical symptoms of the disease by 1.5-4 days and the virus elimination time by 6 days. Conclusions. The use of interferon alfa-2b VIFERON® rectal suppositories and VIFERON® gel for topical administration according to the dose regimen in combination with the standard therapy in COVID-19 children contributed to faster elimination of clinical symptoms of the disease and virus elimination compared to the standard therapy
A tale of company fundamentals vs sentiment driven pricing: The case of GameStop
No full textBy means of the wavelet coherence approach, we study the relationship between the GameStop returns and the sentiment driven pricing, as described by the following indicators: twitter publication count, news publication count excluding twitter, put–call ratio, and short-sale volume. The documented impacts of media-driven sentiment suggest that regulators and policymakers should continuously monitor the investing groups on social media platforms as they can create inefficiency in the market. The put–call ratio strongly and positively affects the GameStop returns prior to the peak of the GameStop saga, being one of the drivers of the January skyrocketing prices. Our results also reveal a positive relationship between the GameStop returns and the short sales volume during the GameStop episode, confirming the short squeeze phenomenon. We highlight the importance for the regulators to consider limiting some predatory short-selling practices, namely “naked” short selling, as excessive short selling may move the market towards inefficiency
Bacterial pneumonia complicating SARS-COV-2: Computed tomography aspects
No full textPurpose. To determine computed tomography diagnostic criteria for early identification of bacterial infection complicating SARS-CoV-2 viral pneumonia, to provide detection and timely treat the secondary bacterial lung complications in patients with COVID-19 infection. Materials and methods. This study was designed as a retrospective cohort clinical trial. The total of 58 patients was enrolled. All of them had received medical treatment in Pirogov National Medical and Surgical Center, Moscow from 01.03.2020 to 15.06.2020 due to the SARS-CoV-2 infection. The cohort was subdivided into two groups that included 26 and 32 patients, respectively. In the first group (n = 26) was made based on clinical course of the disease and laboratory findings, the secondary bacterial infection on top of the preexisting viral lesions was detect and treated. The patients that showed no clinical or laboratory signs of secondary infection (n = 32) were included in the second control group. All of the radiographic (CT) findings in both groups were listed and subsequently thoroughly analyzed by means of statistics. Results. The most informative CT features of associated secondary bacterial pneumonia in our study were: areas of consolidation corresponding to the segmental structure of the lungs; the border of consolidation, mostly following the interlobar pleura; consolidation that occurs during the last 5-7 days in the area with unchanged parenchyma on initial scan. It was also noted specific subtype of air bronchogram, which included easily traceable bronchi from central areas to periphery. Conclusion. Computed tomography can be efficiently used with clinical and laboratory criteria to determine the secondary bacterial infection complicating SARS-CoV-2 viral pneumonia