Clinical Characteristics, Diagnosis, and Therapeutics of COVID-19: A Review.

The novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) that suddenly emerged at the end of December 2019 and caused coronavirus disease 2019 (COVID-19) continues to afflict humanity, not only seriously affecting healthcare systems but also leading to global social and economic imbalances. As of August 2022, there were approximately 580 million confirmed cases of COVID-19 and approximately 6.4 million confirmed deaths due to this disease. The data are sufficient to highlight the seriousness of SARS-CoV-2 infection. Although most patients with COVID-19 present primarily with respiratory symptoms, an increasing number of extrapulmonary systemic symptoms and manifestations have been associated with COVID-19. Since the outbreak of COVID-19, much has been learned about the disease and its causative agent. Therefore, great effort has been aimed at developing treatments and drug interventions to treat and reduce the incidence of COVID-19. In this narrative review, we provide a brief overview of the epidemiology, mechanisms, clinical manifestations, diagnosis, and therapeutics of COVID-19.

[Effects of Combination of Organic and Inorganic Nitrogen on Nitrification and Denitrification in Two Salinized Soils].

Focusing on typical mildly saline soil, S1 (EC, 0.62 dS·m-1), and moderately saline soil, S2 (EC, 1.17 dS·m-1), in Hetao Irrigation District of Inner Mongolia, the response of nitrification and denitrification process to salinization degree and the proportion of organic and inorganic nitrogen application were studied. The experimental treatments consisted of(1) no nitrogen(CK), (2) only inorganic nitrogen(U1), and(3) organic nitrogen(U3O1, U1O1, U1O3, and O1) compared to 25%, 50%, 75%, and 100% inorganic nitrogen. The results showed that increasing salinity reduced the soil nitrification potential and increased the soil denitrification capacity. The soil nitrification potential of the S1 soil was 28.81%-69.67% higher than that of the S2 soil, while the denitrification capacity was reduced by 17.16%-88.91%. With an increase in salinity, the AOB abundance and nitrification contribution rate were reduced, but the AOA abundance and nitrification contribution rate were increased. Furthermore, an increase in salinity increased the abundance of nirK and nirS bacteria, and increased N2O/(N2O+N2) production, but reduced the abundance of nosZ. In the S1 soil, the nitrification potential and denitrification capacity of U1O1 were highest, increasing by as much as 18.59% and 15.87%, respectively, compared to the U1 treatment. In the S2 soil, the difference in the soil nitrification potential between the various fertilization treatments was not significant, and the denitrification capacity of the O1 treatment was highest. The S1 and S2 saline soils treated with U1O1 and O1, respectively, had higher AOB gene abundance and nitrification contribution rates, increased nirS and nosZ gene abundances, and significantly reduced N2O/(N2O+N2) product ratios. Our findings suggested that mildly saline soils(120 kg·hm-2 urea+120 kg·hm-2 organic fertilizer) and moderately saline soils(240 kg·hm-2 organic fertilizer) are more conducive to soil nitrification and denitrification processes compared to soils to which inorganic nitrogen is applied alone.

[Effects of the Combined Application of Organic and Inorganic fertilizers on N2 O Emissions from Saline Soil].

Combining organic fertilizer with chemical fertilizer may affect the microbial processes related to nitrous oxide (N2O) emissions under different degrees of soil salinization. A mild saline soil (S1; electrical conductivity (EC) 0.46 dS·m-1) and moderate saline soil (S2; EC 1.07 dS·m-1) in the Hetao irrigation district of Inner Mongolia were selected. Under equal N rates, the study involved five treatments:U1 (240 kg·hm-2 of chemical fertilizer), U3O1 (180 kg·hm-2 of chemical fertilizer+60 kg·hm-2 of organic fertilizer), U1O1 (120 kg·hm-2 of chemical fertilizer+120 kg·hm-2 of organic fertilizer), U1O3 (60 kg·hm-2 of chemical fertilizer+180 kg·hm-2 of organic fertilizer), and O1 (240 kg·hm-2 of organic fertilizer). In addition, a blank control treatment (CK) was employed to investigate the effects of different fertilization treatments on the N2O emissions from the two saline soils. The results showed that the total N2O emissions from the S2 soil in the same treatment were between 11.86% and 47.23% higher than those from the S1 soil (P<0.05). the dynamic trend of the soil N2O fluxes among the different treatments were similar. The peak N2O emissions occurred after fertilization, and the N2O cumulative emission fluxes accounted for nearly 60% of the emissions during the entire growth period. The proper application of organic fertilizer could significantly reduce the soil N2O emission; the S1 and S2 saline soils treated with U1O1 and O1, respectively, had the lowest N2O emissions, whereby there were significant reductions of 33.62% and 28.51% in comparison to the U1 treatment (P<0.05). Moreover, higher maize yields could be obtained and the N2O flux was significantly positively correlated with the NH4+-N content (P<0.01) but negatively correlated with the NO3--N content. The results demonstrated that nitrification was the main way to produce N2O in the studied salinized maize farmland, and that the addition of organic fertilizer could reduce the N2O production by decreasing the soil NH4+-N content. Based on the changes in the corn yield and a reduction in the greenhouse effect, suitable organic and inorganic fertilizer management models for the Hetao irrigation area were the mild saline soil:120 kg·hm-2 of urea +120 kg·hm-2 of organic fertilizer), and the moderate saline soil:240 kg·hm-2 of organic fertilizer.

Vascular endothelial injury in severe fever with thrombocytopenia syndrome caused by the novel bunyavirus.

Severe fever with thrombocytopenia syndrome virus (SFTSV) infection typically causes acute fever, thrombocytopenia and leucopenia, presenting with a high case fatality rate. The pathogenesis of SFTSV infection, however, is not well described. It was hypothesized that endothelial dysfunction might play part in the disease process. In current study, we retrospectively analyzed the clinical manifestations among a large group of confirmed SFTS cases and found evidence of plasma leakage and vascular endothelial injury. Then we established a SFTSV infection cell model and determined the infectivity and stimulation of SFTSV on vascular endothelial cells in vitro. The hyperpermeability of endothelial cells directly induced by SFTSV was confirmed by electrical resistance and dextran diffusion assay. The virus induced alterations of cell junctions and cytoskeleton was also revealed. It's suggested that vascular endothelial cell injury and barrier function damage were induced after SFTSV infection, which is a vital but neglected pathogenesis of SFTS.