ABSTRACT
COVID-19 is a viral respiratory infection caused by SARS-CoV-2. The immune system plays a pivotal role in disease resolution but can also be detrimental to the clinical outcome in case of unbalanced immune activation. In this study, we have focused on the parallel expression of IL-6, a potent pro-inflammatory cytokine, and IL-10, an important regulator of the immune response, in COVID-19 patients. Using bead-based multiplex immunoassay technology we compared the serum levels of IL-6 and IL-10 in 47 COVID-19 patients with mild, moderate, or severe disease. The serum concentrations of both cytokines were significantly elevated in patients with severe COVID-19, and there was a significant positive correlation between IL-6 and IL-10 in the moderate and severe groups (R=0.6;p< 0.001). Our observations support that IL-6 is one of the driving forces for the cytokine release syndrome in COVID-19 while the immunosuppressive properties of IL-10 in severe disease act as a hindrance to viral clearance.
ABSTRACT
Non-SARS coronaviruses (HCoVs) contribute substantially to seasonal common colds. Their structural homology with SARS-CoV-2 suggests a possible cross-reactivity and cross-protection. The presence of IgG to the most common HCoVs (NL63, 229E, OC43, HKU1) in correlation with RBD-specific IgG and IgA, and the susceptibility to SARS-CoV-2 infection was evaluated in 48 individuals with recently diagnosed moderate SARS-CoV-2 infection (A, n=24) or intensive exposure to SARS-CoV-2 (B, n=24). Anti-S1 IgG for each of the four HCoVs, alongside with RBD-IgG and RBD-IgA were evaluated using ELISA (Creative Diagnostics, USA;Euroimmune, Germany). RBD-specific IgG and IgA were detected in 37% and 71% of group A (average levels 8.5 and 6.8) and 42% and 29% of group B (average levels 3.4 and 4.6 respectively, p < 0.05). IgG specific for NL63, 229E, and OC43 was present in 100.0%, and for HKU-1 - in 94% of tested samples (average index 7.4, 3.9, 4.1, and 2.6, respectively). The levels of IgG to NL63 and 229E did not differ significantly between the groups (7.6 vs.7.2;3.7 vs. 4.1, p > 0.05), nor did correlate with anti-SARS-CoV-2 response. HKU-1-specific IgG was significantly decreased in COVID-19 patients (A) as compared to SARS-CoV-2 resistant donors (B): 1.98vs.3.2, p < 0.01. Curiously, OC43-specific IgG was lower in the group with intensive exposure to SARS-CoV-2 (3.5vs.4.7, p < 0.01), and correlated with RBD-specific IgA (R=0.42, p < 0.05). IgG to seasonal coronaviruses is commonly detected, but only HKU-1-specific IgG was associated with resistance to SARS-CoV-2 infection. OC43-specific IgG may be induced simultaneously with RBD-specific IgA and interfere with SARS-CoV-2 neutralization.
ABSTRACT
In December 2019 a newly described single-stranded coronavirus, later named SARS-CoV-2, started its expansion around the world and subsequently caused a global pandemic, affecting the lives of millions of people worldwide. SARS-CoV-2 can bind multiple receptors on different cells and thus invade many target organs, including the respiratory and gastrointestinal mucous membranes, lungs, central nervous system, heart, etc. This virus can affect the kidney tissue both directly and as a consequence of other organ involvement or of the treatment administered, causing acute kidney injury and leaving long term squeals that worsen the prognosis. We describe three patients with acute kidney injury and subsequent acute renal failure at the background of coronaviral infection. Copyright © 2022 M. Nikolova et al., published by Sciendo.
ABSTRACT
The rural development policy in Bulgaria is aimed at achieving sustainable development of the economic sectors, as the rural area is a place for development not only for agricultural activities, but also it offers good prospects for economic development on a regional scale, through adequate business support, job creation and tourism development. Therefore, the interconnection and interdependence between the two economic sectors is especially important to find opportunities for the development of alternative tourism with the formation of unique tourism products and the application of environmentally-friendly agricultural practices in order to achieve higher living standards and economic benefits for local communities. The problem is that the current pandemic conditions of last year and this year impose a number of restrictions to a greater or lesser extent on each of the economic sectors. The aim of our research is related to the study of interconnection and interdependence of key economic sectors - agriculture and tourism in crisis conditions. The research methods used in the study include: basic scientific research methods, questionnaire survey, summary and synthesis, logical method, tabular and graphical presentation of characteristics and trends. The results of the research can be systematized in several directions: analysis of the connections and interdependence of the sectors through the opportunities for creation of unique tourist products and through diversification of the activities in the rural areas. In conclusion, the pandemic inevitably affects the economic sectors, with greater constraints on the tourism business, where the preferences of potential tourists are focused on domestic alternative tourism. In the construction of unique and specific tourist products in rural areas, the relationship agriculture - tourism is strongly emphasized in terms of requirements for clean and healthy foods, incl. organic food or the purchase of local food products from the region. The diversification of activities in rural areas through the development of tourism provides an opportunity for the development of entrepreneurial initiatives. The strong connection and interdependence between the economic subjects in the indicated economic branches of key importance is fully manifested in a good combination of the interests of all participants concerned in the process of development of the specific territory/region.