Four new eudesmane-type and one new eremophilane-type sesquiterpenes from the whole plant of Carpesium abrotanoides L.

The extract of the whole plant of Carpesium abrotanoides L. yielded five new sesquiterpenes including four eudesmanes (1-4) and one eremophilane (5). The new compounds were characterized by spectroscopic analysis especially 1D and 2D NMR spectroscopy and HRESIMS data. Structurally, both compounds 1 and 2 were sesquiterpene epoxides and 2 owned an epoxy group at C-4/C-15 position to form a spiro skeleton. Compounds 4 and 5 were two sesquiterpenes without lactones and 5 possessed a carboxy group in the molecule. Additionally, all the isolated compounds were preliminarily evaluated for the inhibitory activity against SARS-CoV-2 main protease. As a result, compound 2 showed moderate activity with an IC50 value of 18.79 µM, while other compounds were devoid of noticeable activity (IC50 > 50 µM).

Culturing Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) for Diagnosis and Genome Sequencing.

OBJECTIVE: The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) nucleic acid detection "re-positive" phenomenon is encountered clinically. The accuracy of a viral nucleic acid test is crucial to prevent reintroduction of the virus into the community. This study evaluated the effect of virus culturing on increasing the sensitivity and specificity of real-time polymerase chain reaction (RT-PCR) detection and viral genomic sequencing. METHODS: A series of tenfold dilutions of a SARS-CoV-2 viral stock were conducted and cultured for either 24 or 48 hours. The viral load of cultured samples was determined by RT-PCR. The cultured and non-cultured samples of 1x 50% tissue culture infectious dose (TCID50) were sequenced using metagenomic next-generation sequencing. The depth and coverage of SARS-CoV-2 genome were measured. RESULTS: The lowest viral load detectable in a sample with RT-PCR was 0.01 TCID50. After a 24-h culture, the viral ORF 1ab and N-gene cycle threshold (CT) values were reduced by 4.4 points and 1 point, respectively. One TCID50 viral load of post 24-h culture revealed the sequence depth reached an average of 752 reads, compared with 0.15 in the nonculture; furthermore, the coverage was 99.99% while 6.42% in the nonculture. CONCLUSION: These results indicate that virus culturing can significantly increase the viral load, which can increase the certainty of true-positive detection of the viral nucleic acids, and improve the quality of virus genomic sequencing.

Study on the clinical features and prognosis of second and third generations of COVID-19.

Background: There have been no studies examining differences in clinical manifestations and prognosis between second and third generation coronavirus disease 2019 (COVID-19) patients. Our object was to analyze the epidemiological data and correlation between clinical types and COVID-19 generations. Methods: Older than 18 years COVID-19 patients who met two of the three items listed in COVID-19 Diagnosis Protocol were enrolled and divided into two groups based on epidemiological history. Clinical characteristics (age, gender, body mass index, course), disease severity, laboratory results (platelets, white blood cells, lymphocytes, inflammatory biomarkers, alanine aminotransferase, lactate dehydrogenase, creatine kinase, myoglobin, troponin, D-dimer blood biochemical indexes), clinical types were analyzed. Two groups were compared by chi-square test, group means were compared by t test, correlation between COVID-19 generations and clinical severity and clinical types were examined by Spearman correlation analysis. Results: There were no significant differences in gender composition (P=0.488), A-DROP scores (P=0.079) nor BMI (P=0.532) between the two generations. The number of second generation patients over 60 years was significantly greater than that in third generation (P<0.001). Creatine kinase levels of third generation patients were significantly higher than those of second generation patients at admission (P=0.009) and during hospitalization (P=0.023). The troponin levels of third generation patients were significantly higher than those of second generation patients at admission (P=0.020). At discharged, the creatine kinase and troponin levels were not significantly different between the two generations. Rate of severe (P=0.130) and critical cases (P=0.314) in second generation COVID-19 patients was not significantly different from that of third generation patients. Age (ρ=0.224, P<0.001), duration (ρ=0.317, P<0.001), transmission generation (ρ=0.269, P<0.001), serum creatine kinase (ρ=0.240, P<0.001), troponin (ρ=0.296, P<0.001), C-reaction protein (ρ=0.278, P<0.001), procalcitonin levels (ρ=0.221, P=0.001), lymphocyte count (ρ=-0.245, P<0.001), and platelet count (ρ=-0.265, P<0.001) of COVID-19 patients were significantly s correlated with clinical types. Conclusions: Increased virulence may occur in specific tissues and organs during intergenerational transmission of COVID-19 virus. COVID-19 virus virulence in different regions is different. The clinical prognosis of COVID-19 patients is closely related to age, course, transmission generations, and some laboratory indicators. Transmission generation, regional differences, and laboratory indicators may have certain potential value in predicting prognosis and treatment.

Contribution of CD4+ T cell-mediated inflammation to diarrhea in patients with COVID-19.

OBJECTIVES: This study aimed to explore the role of CD4+ T cells in the mechanisms of COVID-19 related diarrhea. METHODS: We analyzed lymphocyte subsets in patients with COVID-19 and the expression of angiotensin-converting enzyme 2 (ACE2), the transmembrane protease serine 2, and CD4+ T cell-related indicators in the colon were compared between patients with and without diarrhea. Correlation analyses were performed for ACE2 and other indicators to identify the relationship between SARS-CoV-2 infection and CD4+ mediated inflammation. The expression and distribution of CD4+ T cell-associated chemokines and their receptors were detected to determine the possibility of migration of CD4+ T cells to inflammation sites. RESULTS: The CD4+ T cell counts and percentages and CD4/CD8 ratio showed the most significant differences between the 2 groups. The diarrhea group expressed higher levels of ACE2, T-box expressed in T cells (Tbet), and tumor necrosis factor-alpha (TNFα) at both the mRNA and protein levels, with no difference from the nondiarrhea group for the percentage of ACE2+TNFα+ cells, indicating an indirect association between ACE2 and TNFα. The mRNA expression of CXCL10, CXCL11, and CXCR3 and the number of CD4+CXCR3+T cells were increased in the diarrhea group. CONCLUSIONS: CD4+ T cell-mediated inflammation may contribute to COVID-19 related diarrhea. CXCR3+ mediated migration of CD4+ T cells into the gut may perpetuate inflammation.

Co-infecting pathogens can contribute to inflammatory responses and severe symptoms in COVID-19.

Background: The current COVID-19 pandemic is posing a major challenge to public health on a global scale. While it is generally believed that severe COVID-19 results from over-expression of inflammatory mediators (i.e., a "cytokine storm"), it is still unclear whether and how co-infecting pathogens contribute to disease pathogenesis. To address this, we followed the entire course of the disease in cases with severe or critical COVID-19 to determine the presence and abundance of all potential pathogens present-the total "infectome"-and how they interact with the host immune system in the context of severe COVID-19. Methods: We examined one severe and three critical cases of COVID-19, as well as a set of healthy controls, with longitudinal samples (throat swab, whole blood, and serum) collected from each case. Total RNA sequencing (meta-transcriptomics) was performed to simultaneously investigate pathogen diversity and abundance, as well as host immune responses, in each sample. A Bio-Plex method was used to measure serum cytokine and chemokine levels. Results: Eight pathogens, SARS-CoV-2, Aspergillus fumigatus (A. fumigatus), Mycoplasma orale (M. orale), Myroides odoratus (M. odoratus), Acinetobacter baumannii (A. baumannii), Candida tropicalis, herpes simplex virus (HSV) and human cytomegalovirus (CMV), identified in patients with COVID-19 appeared at different stages of the disease. The dynamics of inflammatory mediators in serum and the respiratory tract were more strongly associated with the dynamics of the infectome compared with SARS-CoV-2 alone. Correlation analysis revealed that pulmonary injury was directly associated with cytokine levels, which in turn were associated with the proliferation of SARS-CoV-2 and co-infecting pathogens. Conclusions: For each patient, the cytokine storm that resulted in acute lung injury and death involved a dynamic and highly complex infectome, of which SARS-CoV-2 was a component. These results indicate the need for a precision medicine approach to investigate both the infection and host response as a standard means of infectious disease characterization.

Challenges and Opportunities of Teaching Online in an Iranian EFL High School Context during the COVID-19 Pandemic

With the COVID-19 pandemic sweeping the globe and the transition of education to fully online teaching in Iran, high school English teachers who were accustomed to teaching offline had to face a lot of challenges during this shift. In this paper, we describe the major challenges or dilemmas the first author had to surmount during his online English teaching to a group of senior high school students in the 2020-2021 academic year, how he managed to resolve those dilemmas (e.g., in teaching reading) under the second author's expert guidance, and the opportunities afforded to him by this experience. The paper has implications for teachers who teach in similar English as a foreign language (EFL) contexts and who are confronted with similar challenges.

Should people with chronic liver diseases be vaccinated against COVID-19?

Hepatic impairment in coronavirus disease 2019 (COVID-19) may derive from cholangiocyte damage in the beginning, but not from direct infection of hepatocytes. Chronic liver disease patients co-infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) exhibited overexpression of angiotensin-converting enzyme 2 receptors and overwhelming cytokine storm. Consensus has been reached that we should encourage as many people as possible to be vaccinated in order to achieve herd immunity. SARS-CoV-2 vaccines can prevent or alleviate severe infection and cytokine storm. It is recommended that all adult patients with chronic liver diseases and liver transplant recipients should receive COVID-19 vaccines using the standard dose and schedule. Data is not yet sufficient to compare the efficacy of different types of vaccines used in chronic liver disease patients.

Associations of immunological features with COVID-19 severity: a systematic review and meta-analysis.

BACKGROUND: COVID-19 has spread widely worldwide, causing millions of deaths. We aim to explore the association of immunological features with COVID-19 severity. METHODS: We conducted a meta-analysis to estimate mean difference (MD) of immune cells and cytokines levels with COVID-19 severity in PubMed, Web of Science, Scopus, the Cochrane Library and the grey literature. RESULTS: A total of 21 studies with 2033 COVID-19 patients were included. Compared with mild cases, severe cases showed significantly lower levels of immune cells including CD3+ T cell (× 106, MD, - 413.87; 95%CI, - 611.39 to - 216.34), CD4+ T cell (× 106, MD, - 203.56; 95%CI, - 277.94 to - 129.18), CD8+ T cell (× 106, MD, - 128.88; 95%CI, - 163.97 to - 93.79), B cell (× 106/L; MD, - 23.87; 95%CI, - 43.97 to - 3.78) and NK cell (× 106/L; MD, - 57.12; 95%CI, - 81.18 to - 33.06), and significantly higher levels of cytokines including TNF-α (pg/ml; MD, 0.34; 95%CI, 0.09 to 0.59), IL-5 (pg/ml; MD, 14.2; 95%CI, 3.99 to 24.4), IL-6 (pg/ml; MD, 13.07; 95%CI, 9.80 to 16.35), and IL-10 (pg/ml; MD, 2.04; 95%CI, 1.32 to 2.75), and significantly higher levels of chemokines as MCP-1 (SMD, 3.41; 95%CI, 2.42 to 4.40), IP-10 (SMD, 2.82; 95%CI, 1.20 to 4.45) and eotaxin (SMD, 1.55; 95%CI, 0.05 to 3.05). However, no significant difference was found in other indicators such as Treg cell (× 106, MD, - 0.13; 95%CI, - 1.40 to 1.14), CD4+/CD8+ ratio (MD, 0.26; 95%CI, - 0.02 to 0.55), IFN-γ (pg/ml; MD, 0.26; 95%CI, - 0.05 to 0.56), IL-2 (pg/ml; MD, 0.05; 95%CI, - 0.49 to 0.60), IL-4 (pg/ml; MD, - 0.03; 95%CI, - 0.68 to 0.62), GM-CSF (SMD, 0.44; 95%CI, - 0.46 to 1.35), and RANTES (SMD, 0.94; 95%CI, - 2.88 to 4.75). CONCLUSION: Our meta-analysis revealed significantly lower levels of immune cells (CD3+ T, CD4+ T, CD8+ T, B and NK cells), higher levels of cytokines (TNF-α, IL-5, IL-6 and IL-10) and higher levels of chemokines (MCP-1, IP-10 and eotaxin) in severe cases in comparison to mild cases of COVID-19. Measurement of immunological features could help assess disease severity for effective triage of COVID-19 patients.

A New Optimal Diagnosis System for Coronavirus (COVID-19) Diagnosis Based on Archimedes Optimization Algorithm on Chest X-Ray Images.

The new coronavirus, COVID-19, has affected people all over the world. Coronaviruses are a large group of viruses that can infect animals and humans and cause respiratory distress; these discomforts may be as mild as a cold or as severe as pneumonia. Correct detection of this disease can help to avoid its spreading increasingly. In this paper, a new CAD-based approach is suggested for the optimal diagnosis of this disease from chest X-ray images. The proposed method starts with a min-max normalization to scale all data into a normal scale, and then, histogram equalization is performed to improve the quality of the image before main processing. Afterward, 18 different features are extracted from the image. To decrease the method difficulty, the minimum features are selected based on a metaheuristic called Archimedes optimization algorithm (AOA). The model is then implemented on three datasets, and its results are compared with four other state-of-the-art methods. The final results indicated that the proposed method with 86% accuracy and 96% precision has the highest balance between accuracy and reliability with the compared methods as a diagnostic system for COVID-19.

Positive virus detection in patients who recovered from COVID-19 during quarantine period between discharge and home: a two-center experience in Wuhan, China.

The incidence of re-positive virus detection in patients who recovered from COVID-19 during quarantine was 6.2% in two designated locations, in Wuhan, indicating that suggestions for patients after discharge to be quarantined before leaving for home might be necessary. This experience might be referred to by other countries with epidemic outbreak.

Absolute Eosinophil Count Predicts Intensive Care Unit Transfer Among Elderly COVID-19 Patients From General Isolation Wards.

Objectives: As of June 1, 2020, coronavirus disease 2019 (COVID-19) has caused a global pandemic and resulted in over 370,000 deaths worldwide. Early identification of COVID-19 patients who need to be admitted to the intensive care unit (ICU) helps to improve the outcomes. We aim to investigate whether absolute eosinophil count (AEC) can predict ICU transfer among elderly COVID-19 patients from general isolation wards. Methods: A retrospective study of 94 elderly patients older than 60 years old with COVID-19 was conducted. We compared the basic clinical characteristics and levels of inflammation markers on admission to general isolation wards and the needs for ICU transfer between the eosinopenia (AEC on admission <20 cells/µl) and non-eosinopenia (AEC ≥20 cells/µl) groups. Results: There was a significantly higher ICU transfer rate in the eosinopenia group than in the non-eosinopenia group (51 vs. 9%, P < 0.001). Multivariate analysis revealed that eosinopenia was associated with an increased risk of ICU transfer in elderly COVID-19 patients [adjusted odds ratio (OR) 6.12 (95% CI, 1.23-30.33), P = 0.027] after adjustment of age, lymphocyte count, neutrophil count, C-reactive protein (CRP), and ferritin levels. The eosinopenia group had higher levels of CRP, ferritin, and cytokines [interleukin-2 receptor (IL-2R), interleukin-6 (IL-6), interleukin-8 (IL-8), interleukin-10 (IL-10), and tumor necrosis factor-α (TNF-α)] than the non-eosinophil group (P < 0.001). The area under the curve of AEC on admission for predicting ICU transfer among elderly COVID-19 patients was 0.828 (95% CI, 0.732-0.923). The best cut-off value of AEC was 25 cells/µl with a sensitivity of 91% and a specificity of 71%, respectively. Conclusion: Absolute eosinophil count on admission is a valid predictive marker for ICU transfer among elderly COVID-19 patients from general isolation wards and, therefore, can help case triage and optimize ICU utilization, especially for health care facilities with limited ICU capacity.

Human post-infection serological response to the spike and nucleocapsid proteins of SARS-CoV-2.

To inform seroepidemiological studies, we characterized the IgG- responses in COVID-19 patients against the two major SARS-CoV-2 viral proteins, spike (S) and nucleocapsid (N). We tested 70 COVID-19 sera collected up to 85 days post-symptom onset and 230 non-COVID-19 sera, including 27 SARS sera from 2003. Although the average SARS-CoV-2 S and N-IgG titers were comparable, N-responses were more variable among individuals. S- and N-assay specificity tested with non-COVID-19 sera were comparable at 97.5% and 97.0%, respectively. Therefore, S will make a better target due to its lower cross-reactive potential and its' more consistent frequency of detection compared to N.

Clinical characteristics in patients with SARS-CoV-2/HBV co-infection.

COVID-19 has become a global pandemic and garnered international attention. Although the clinical features of COVID-19-related liver injury have been investigated, there have been no reports and studies on the clinical characteristics of COVID-19 patients co-infected with hepatitis B virus (HBV). This study aimed to evaluate whether SARS-CoV-2/HBV co-infection could influence liver function and the disease outcome. All 326 confirmed COVID-19 cases in Shanghai Public Health Clinical Center (The COVID-19 designated hospital in Shanghai, China) from 20 January 2020 to 24 February 2020 were enrolled and followed up until February 29 in this study. The clinical, laboratory data and the length of stay were collected and analysed retrospectively. 20 patients with HBV co-infection (6.1%) and 306 patients (93.9%) without HBV infection showed no differences in the level of liver function parameters. However, compared with HBsAg- patients [145.4 mg/L (103.9-179.2)], HBsAg + patients had a lower level of prealbumin [(102.3 mg/L (76.22-160.2), P = .0367]. There were also no significant differences for the discharge rate and the length of stay between two groups. Taken together, we found no evidence that SARS-CoV-2/HBV co-infection could aggravate liver injury or extend duration of hospitalization.

Clinical Features of COVID-19-Related Liver Functional Abnormality.

BACKGROUND & AIMS: Some patients with SARS-CoV-2 infection have abnormal liver function. We aimed to clarify the features of COVID-19-related liver damage to provide references for clinical treatment. METHODS: We performed a retrospective, single-center study of 148 consecutive patients with confirmed COVID-19 (73 female, 75 male; mean age, 50 years) at the Shanghai Public Health Clinical Center from January 20 through January 31, 2020. Patient outcomes were followed until February 19, 2020. Patients were analyzed for clinical features, laboratory parameters (including liver function tests), medications, and length of hospital stay. Abnormal liver function was defined as increased levels of alanine and aspartate aminotransferase, gamma glutamyltransferase, alkaline phosphatase, and total bilirubin. RESULTS: Fifty-five patients (37.2%) had abnormal liver function at hospital admission; 14.5% of these patients had high fever (14.5%), compared with 4.3% of patients with normal liver function (P = .027). Patients with abnormal liver function were more likely to be male, and had higher levels of procalcitonin and C-reactive protein. There was no statistical difference between groups in medications taken before hospitalization; a significantly higher proportion of patients with abnormal liver function (57.8%) had received lopinavir/ritonavir after admission compared to patients with normal liver function (31.3%). Patients with abnormal liver function had longer mean hospital stays (15.09 ± 4.79 days) than patients with normal liver function (12.76 ± 4.14 days) (P = .021). CONCLUSIONS: More than one third of patients admitted to the hospital with SARS-CoV-2 infection have abnormal liver function, and this is associated with longer hospital stay. A significantly higher proportion of patients with abnormal liver function had received lopinavir/ritonavir after admission; these drugs should be given with caution.