ABSTRACT
COVID-19 is a severe acute respiratory syndrome caused by a novel coronavirus, SARS-CoV- 2.COVID-19 is now a pandemic, and is not yet fully under control.As the surface spike protein (S) mediates the recognition between the virus and cell membrane and the process of cell entry, it plays an important role in the course of disease transmission.The study on the S protein not only elucidates the structure and function of virus-related proteins and explains their cellular entry mechanism, but also provides valuable information for the prevention, diagnosis and treatment of COVII)-19.Concentrated on the S protein of SARS-CoV-2, this review covers four aspects: (1 ) The structure of the S protein and its binding with angiotensin converting enzyme II (ACE2) , the specific receptor of SARS-CoV-2, is introduced in detail.Compared with SARS-CoV, the receptor binding domain (RBD) of the SARS-CoV- 2 S protein has a higher affinity with ACE2, while the affinity of the entire S protein is on the contrary.(2) Currently, the cell entry mechanism of SARS-CoV-2 meditated by the S protein is proposed to include endosomal and non-endosomal pathways.With the recognition and binding between the S protein and ACE2 or after cell entry, transmembrane protease serine 2(TMPRSS2) , lysosomal cathepsin or the furin enzyme can cleave S protein at S1/S2 cleavage site, facilitating the fusion between the virus and target membrane.(3) For the progress in SARS-CoV-2 S protein antibodies, a collection of significant antibodies are introduced and compared in the fields of the target, source and type.(4) Mechanisms of therapeutic treatments for SARS-CoV-2 varied.Though the antibody and medicine treatments related to the SARS-CoV-2 S protein are of high specificity and great efficacy, the mechanism, safety, applicability and stability of some agents are still unclear and need further assessment.Therefore, to curb the pandemic, researchers in all fields need more cooperation in the development of SARS-CoV-2 antibodies and medicines to face the great challenge.Copyright © Palaeogeography (Chinese Edition).All right reserved.
ABSTRACT
One of the symptoms of a new coronavirus infection (COVID-19) is a complete or partial violation of the sense of smell. The aim of the work is to analyze the published results of scientific research on the mechanisms of olfactory impairment in COVID-19. Material and methods. Research was conducted for publications in Pubmed on the problem of olfactory impairment in COVID-19 using terms indexed by MeSH. The systematic review was compiled in accordance with the checklist Preferred Reporting Items for Systematic Reviews and Meta-Analyses Statement (PRISMA). Results. Publication's analysis has shown that the existing ideas about conductive anosmia are insufficient to explain the causes of olfactory impairment caused by SARS-CoV-2. It has been established that ACE2 and TMPRSS2 receptors located on the surface of target cells are necessary for the penetration of a new coronavirus. It is known that these receptors are mainly located on the cells of the olfactory epithelium. The main hypothesis of olfactory impairment in COVID-19 is that anosmia/hyposmia is caused by damage not to neuronal cells (as previously assumed), but to the olfactory epithelium. There is no confirmation of the point of view about the damage of SARS-CoV-2 olfactory bulbs and olfactory neurons, since they do not express receptor proteins for the virus on their surface.Copyright © 2022 by the authors.
ABSTRACT
Coronavirus disease 2019 (Covid 19) is caused by the severe acute respiratory syndrome coronavirus-2 (SARS CoV 2) and causes lymphopenia, immunosuppression, inefficient T and B cell immunity, cytokine storm, and destructive tissue inflammation. Since COVID 19 is a multi-system disease predominantly affecting the lungs, there is doubt on whether chronic lung diseases place patients at higher risk and SARS CoV2 leads to asthma exacerbation. None of the studies have reported asthma or recurrent wheezing as a comorbidity or risk factor for Covid 19 in children up to now. Notably, further studies are needed to explore the relationship between Covid 19 and asthma to improve clinical practice and decrease morbidity and mortality.Copyright © 2020 Bilimsel Tip Yayinevi. All rights reserved.
ABSTRACT
Severe course of cOVID-19 among men compared to the female led to a detailed study of the hormonal status of men with cOVID-19. The earliest works about this focused on the incidence and severity of cOVID-19 depending on the intake of androgen deprivation therapy. At the same time, different classes of androgen deprivation therapy have different effects on androgen concentration that was not always considered in the analysis. In this regard, we conducted a review of the available literature data with a targeted study of works that included androgen deprivation therapy with a unidirectional effect on the concentration of male sex hormones. In addition, we conducted a review of studies focused on the relationship between cOVID-19 and androgens (testosterone and dihydrotestosterone).Copyright © 2022 Authors. All rights reserved.
ABSTRACT
The decline in vaccine efficacy and the risk of reinfection by SARS-CoV-2 make new studies important to better characterize the immune response against the virus and its components. Here, we investigated the pattern of activation of T-cells and the expression of inflammatory factors by PBMCs obtained from naive and previously infected subjects following COVID-19 vaccination, after PBMCs stimulation with S1, RBD, and N-RBD SARS-CoV-2 proteins. PBMCs showed low levels of ACE2 and TMPRSS2 transcripts, which were not modulated by the exposure of these cells to SARS-CoV-2 proteins. Compared to S1 and RBD, N-RBD stimulation showed a greater ability to stimulate T-cell reactivity, according to CD25 and CD69 markers. Interestingly, T-cell reactivity was more pronounced in vaccinated subjects with prior SARS-CoV-2 infection than in vaccinated donors who never had been diagnosed with COVID-19. Finally, N-RBD stimulation promoted greater expression of IL-6 and IFN-gamma in PBMCs, which reinforces the greater immunogenic potential of this protein in the vaccinated subjects. These data suggest that PBMCs from previously infected and vaccinated subjects are more reactive than those derived from just vaccinated donors. Moreover, the N-RBD together viral proteins showed a greater stimulatory capacity than S1 and RBD viral proteins.Copyright © 2022
ABSTRACT
Coronavirus disease 2019 (COVID-19) is now a pandemic and its death toll is rocketing up. Patients with acute kidney injury (AKI) and chronic kidney disease (CKD) are at high risk of developing COVID-19 complications and COVID-19 infection can also lead to renal dysfunction. Considering the importance of kidney function in COVID-19 patients, the present review is aimed to dig into the available evidence about kidney and COVID-19. We summarize the mechanisms underlying the renal injury in COVID-19 patients, and treatment strategies in dialysis and kidney transplant patients. We conclude, it is imperative to highlight the early monitoring of patients with AKI and carefully control kidney function during severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection.Copyright © 2020 The Author(s);.
ABSTRACT
The 2019 novel coronavirus disease (COVID-19) is a newly defined infectious and highly contagious acute disease caused by the severe acute respiratory syndrome coronavirus 2 ( (SARS-CoV-2). COVID-19 is mainly characterized by an acute respiratory disease however it can also affect multiple other organ systems such as the kidney, gastrointestinal tract, heart, vascular system, and the central nervous system. Kidney involvement is frequent in patients with COVID-19 and this review aims to explore the available data on kidney and COVID-19. In conclusion, COVID-19 infection can affect renal function and may cause acute kidney injury (AKI), due to several mechanisms that need to be fully elucidated. As only supportive management strategies are available for treating AKI in COVID-19, it is necessary to identify and preserve renal function during SARS-CoV-2 infection.Copyright © 2021 The Author(s).