Accelerating Cell-Free Biosensors by Entropy-Driven Assembly of Transcription Templates.

Due to its high efficiency and selectivity, cell-free biosynthesis has found broad utility in the fields of bioproduction, environment monitoring, and disease diagnostics. However, the practical application is limited by its low productivity. Here, we introduce the entropy-driven assembly of transcription templates as dynamic amplifying modules to accelerate the cell-free transcription process. The catalytic DNA circuit with high sensitivity and enzyme-free format contributes to the production of large amounts of transcription templates, drastically accelerating the as-designed cell-free transcription system without interference from multiple enzymes. The proposed approach was successfully applied to the ultrasensitive detection of SARS-CoV-2, improving the sensitivity by 3 orders of magnitude. Thanks to the high programmability and diverse light-up RNA pairs, the method can be adapted to multiplexing detection, successfully demonstrated by the analysis of two different sites of the SARS-CoV-2 gene in parallel. Further, the flexibility of the entropy-driven circuit enables a dynamic responding range by tuning the circuit layers, which is beneficial for responding to targets with different concentration ranges. The strategy was also applied to the analysis of clinical samples, providing an alternative for sensitively detecting the current SARS-CoV-2 RNA that quickly mutates.

SARS-CoV-2 epitope-specific T cells: Immunity response feature, TCR repertoire characteristics and cross-reactivity.

The devastating COVID-19 pandemic caused by SARS-CoV-2 and multiple variants or subvariants remains an ongoing global challenge. SARS-CoV-2-specific T cell responses play a critical role in early virus clearance, disease severity control, limiting the viral transmission and underpinning COVID-19 vaccine efficacy. Studies estimated broad and robust T cell responses in each individual recognized at least 30 to 40 SARS-CoV-2 antigen epitopes and associated with COVID-19 clinical outcome. Several key immunodominant viral proteome epitopes, including S protein- and non-S protein-derived epitopes, may primarily induce potent and long-lasting antiviral protective effects. In this review, we summarized the immune response features of immunodominant epitope-specific T cells targeting different SRAS-CoV-2 proteome structures after infection and vaccination, including abundance, magnitude, frequency, phenotypic features and response kinetics. Further, we analyzed the epitopes immunodominance hierarchy in combination with multiple epitope-specific T cell attributes and TCR repertoires characteristics, and discussed the significant implications of cross-reactive T cells toward HCoVs, SRAS-CoV-2 and variants of concern, especially Omicron. This review may be essential for mapping the landscape of T cell responses toward SARS-CoV-2 and optimizing the current vaccine strategy.

Effectiveness and safety of Qingfei Dayuan granules for treating influenza and upper respiratory tract infections manifested by the pulmonary heat-toxin syndrome: A multicenter, randomized, double-blind, placebo-controlled trial.

Background: Patients diagnosed with influenza and upper respiratory tract infections (URTIs) have similar clinical manifestations and biochemical indices and a low detection rate of viral pathogens, mixed infection with diverse respiratory viruses, and targeted antiviral treatment difficulty in the early stage. According to the treatment strategy of "homotherapy for heteropathy" in traditional Chinese medicine (TCM), different diseases with the same clinical symptoms can be treated with the same medicines. Qingfei Dayuan granules (QFDY), a type of Chinese herbal preparation included in the TCM Diagnosis and Treatment Protocol for COVID-19 of Hubei Province issued by the Health Commission of Hubei Province in 2021, are recommended for patients suffering from COVID-19 with symptoms of fever, cough, and fatigue, among others. Additionally, recent studies have shown that QFDY effectively alleviates fever, cough, and other clinical symptoms in patients with influenza and URTIs. Materials and methods: The study was designed as a multicenter, randomized, double-blind, placebo-controlled clinical trial for treatment for influenza and URTIs manifested by pulmonary heat-toxin syndrome (PHTS) with QFDY. A total of 220 eligible patients were enrolled from eight first-class hospitals in five cities of Hubei Province in China and randomly assigned to receive either 15 g of QFDY or a placebo three times a day for 5 days. The primary outcome was the complete fever relief time. Secondary outcomes included efficacy evaluation of TCM syndromes, scores of TCM syndromes, cure rate of each single symptom, incidence of comorbidities and progression to severe conditions, combined medications, and laboratory tests. Safety evaluations mainly involved adverse events (AEs) and changes in vital signs during the study. Results: Compared with the placebo group, the complete fever relief time was shorter in the QFDY group, 24 h (12.0, 48.0) in the full analysis set (FAS) and 24 h (12.0, 49.5) in the per-protocol set (PPS) (p ≤ 0.001). After a 3-day treatment, the clinical recovery rate (22.3% in the FAS and 21.6% in the PPS) and cure rate of cough (38.6% in the FAS and 37.9% in the PPS), a stuffy and running nose, and sneezing (60.0% in the FAS and 59.5% in the PPS) in the QFDY group were higher than those in the placebo group (p < 0.05). The number of patients taking antibiotics for more than 24 h in the placebo group (nine cases) was significantly higher than that in the QFDY group (one case) (p < 0.05). There were no significant differences between the two groups in terms of scores of TCM syndromes, incidence of comorbidities or progression to severe conditions, combined use of acetaminophen tablets or phlegm-resolving medicines, and laboratory tests (p > 0.05). Meanwhile, no significant difference was found in the incidence of AEs and vital signs between the two groups (p > 0.05). Conclusion: The trial showed that QFDY was an effective and safe treatment modality for influenza and URTIs manifested by PHTS because it shortened the complete fever relief time, accelerated clinical recovery, and alleviated symptoms such as cough, a stuffy and running nose, and sneezing during the course of treatment. Clinical trial registration: https://www.chictr.org.cn/showproj.aspx?proj=131702, identifier ChiCTR2100049695.

Effect of Direct Bilirubin Level on Clinical Outcome and Prognoses in Severely/Critically Ill Patients With COVID-19.

Objectives: We aimed to investigate how changes in direct bilirubin (DBiL) levels in severely/critically ill the coronavirus disease (COVID-19) patients during their first week of hospital admission affect their subsequent prognoses and mortality. Methods: We retrospectively enrolled 337 severely/critically ill COVID-19 patients with two consecutive blood tests at hospital admission and about 7 days after. Based on the trend of the two consecutive tests, we categorized patients into the normal direct bilirubin (DBiL) group (224), declined DBiL group (44) and elevated DBiL group (79). Results: The elevated DBiL group had a significantly larger proportion of critically ill patients (χ2-test, p < 0.001), a higher risk of ICU admission, respiratory failure, and shock at hospital admission (χ2-test, all p < 0.001). During hospitalization, the elevated DBiL group had significantly higher risks of shock, acute respiratory distress syndrome (ARDS), and respiratory failure (χ2-test, all p < 0.001). The same findings were observed for heart damage (χ2-test, p = 0.002) and acute renal injury (χ2-test, p = 0.009). Cox regression analysis showed the risk of mortality in the elevated DBiL group was 2.27 (95% CI: 1.50-3.43, p < 0.001) times higher than that in the normal DBiL group after adjusted age, initial symptom, and laboratory markers. The Receiver Operating Characteristic curve (ROC) analysis demonstrated that the second test of DBiL was consistently a better indicator of the occurrence of complications (except shock) and mortality than the first test in severely/critically ill COVID-19 patients. The area under the ROC curve (AUC) combined with two consecutive DBiL levels for respiratory failure and death was the largest. Conclusion: Elevated DBiL levels are an independent indicator for complication and mortality in COVID-19 patients. Compared with the DBiL levels at admission, DBiL levels on days 7 days of hospitalization are more advantageous in predicting the prognoses of COVID-19 in severely/critically ill patients.

Efficient Targeted Delivery of Bifunctional Circular Aptamer-ASO Chimera to Suppress the SARS-CoV-2 Proliferation and Inflammation.

Inhibition of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and excessive inflammation is the current task in the prevention and treatment of corona vireus disease 2019 (COVID-19). Here, a dual-function circular aptamer-ASO chimera (circSApt-NASO) is designed to suppress SARS-CoV-2 replication and inflammation. The chemically unmodified circSApt-NASO exhibits high serum stability by artificial cyclization. It is also demonstrated that the SApt binding to spike protein enables the chimera to be efficiently delivered into the host cells expressing ACE2 along with the infection of SARS-CoV-2. Among them, the SApt potently inhibits spike-induced inflammation. The NASO targeting to silence N genes not only display robust anti-N-induced inflammatory activity, but also achieve efficient inhibition of SARS-CoV-2 replication. Overall, benefiting from the high stability of the cyclization, antispike aptamer-dependent, and viral infection-mediate targeted delivery, the circSApt-NASO displays robust potential against authentic SARS-CoV-2 and Omicron, providing a promising specific anti-inflammatory and antiproliferative reagent for therapeutic COVID-19.

A functional RNA/DNA circuit for one-pot detection of SARS-CoV-2 RNA.

A simple method is proposed in this work for the detection of SARS-CoV-2 RNA based on a functional RNA/DNA circuit. By ingeniously integrating the nucleic acid circuit technology and CRISPR/cas12a system, this method can achieve femtomolar detection of the target RNA in one step and successfully distinguish COVID-19 positive cases from clinical samples, proving its great potential for clinical application.

Clinical characteristics of COVID-19 and analysis of the outcomes in 31 cases

Objective: To describe the clinical characteristics of COVID-I9, and analyze the factors affecting prognosis as well as outcomes of patients for summarizing the clinical experience in diagnosis and treatment of this infection.

Allosteric aptasensor-initiated target cycling and transcription amplification of light-up RNA aptamer for sensitive detection of protein.

The early detection of biomarker proteins in clinical samples is of great significance for the diagnosis of diseases. However, it is still a challenge to detect low-concentration protein. Herein, a label-free aptamer-based amplification assay, termed the ATC-TA system, that allows fluorescence detection of very low numbers of protein without time-consuming washing steps and pre-treatment was developed. The target induces a conformational change in the allosteric aptasensor, triggers the target cycling and transcription amplification, and ultimately converts the input of the target protein into the output of the light-up aptamer (R-Pepper). It exhibits ultrahigh sensitivity with a detection limit of 5.62 fM at 37 â„ƒ and the accuracy is comparable to conventional ELISA. ATC-TA has potential application for the detection of endogenous PDGF-BB in serum samples to distinguish tumor mice from healthy mice at an early stage. It also successfully detects exogenous SARS-CoV-2 spike proteins in human serum. Therefore, this high-sensitive, universality, easy-to-operate and cost-effective biosensing platform holds great clinical application potential in early clinical diagnosis.

Improving antibody affinity through in vitro mutagenesis in complementarity determining regions.

High-affinity antibodies are widely used in diagnostics and for the treatment of human diseases. However, most antibodies are isolated from semi-synthetic libraries by phage display and do not possess in vivo affinity maturation, which is triggered by antigen immunization. It is therefore necessary to engineer the affinity of these antibodies by way of in vitro assaying. In this study, we optimized the affinity of two human monoclonal antibodies which were isolated by phage display in a previous related study. For the 42A1 antibody, which targets the liver cancer antigen glypican-3, the variant T57H in the second complementarity-determining region of the heavy chain (CDR-H2) exhibited a 2.6-fold improvement in affinity, as well as enhanced cell-binding activity. For the I4A3 antibody to severe acute respiratory syndrome coronavirus 2, beneficial single mutations in CDR-H2 and CDR-H3 were randomly combined to select the best synergistic mutations. Among these, the mutation S53P-S98T improved binding affinity (about 3.7 fold) and the neutralizing activity (about 12 fold) compared to the parent antibody. Taken together, single mutations of key residues in antibody CDRs were enough to increase binding affinity with improved antibody functions. The mutagenic combination of key residues in different CDRs creates additive enhancements. Therefore, this study provides a safe and effective in vitro strategy for optimizing antibody affinity.

Effect of Direct Bilirubin Level on Clinical Outcome and Prognoses in Severely/Critically Ill Patients With COVID-19

Objectives We aimed to investigate how changes in direct bilirubin (DBiL) levels in severely/critically ill the coronavirus disease (COVID-19) patients during their first week of hospital admission affect their subsequent prognoses and mortality. Methods We retrospectively enrolled 337 severely/critically ill COVID-19 patients with two consecutive blood tests at hospital admission and about 7 days after. Based on the trend of the two consecutive tests, we categorized patients into the normal direct bilirubin (DBiL) group (224), declined DBiL group (44) and elevated DBiL group (79). Results The elevated DBiL group had a significantly larger proportion of critically ill patients (χ2-test, p < 0.001), a higher risk of ICU admission, respiratory failure, and shock at hospital admission (χ2-test, all p < 0.001). During hospitalization, the elevated DBiL group had significantly higher risks of shock, acute respiratory distress syndrome (ARDS), and respiratory failure (χ2-test, all p < 0.001). The same findings were observed for heart damage (χ2-test, p = 0.002) and acute renal injury (χ2-test, p = 0.009). Cox regression analysis showed the risk of mortality in the elevated DBiL group was 2.27 (95% CI: 1.50–3.43, p < 0.001) times higher than that in the normal DBiL group after adjusted age, initial symptom, and laboratory markers. The Receiver Operating Characteristic curve (ROC) analysis demonstrated that the second test of DBiL was consistently a better indicator of the occurrence of complications (except shock) and mortality than the first test in severely/critically ill COVID-19 patients. The area under the ROC curve (AUC) combined with two consecutive DBiL levels for respiratory failure and death was the largest. Conclusion Elevated DBiL levels are an independent indicator for complication and mortality in COVID-19 patients. Compared with the DBiL levels at admission, DBiL levels on days 7 days of hospitalization are more advantageous in predicting the prognoses of COVID-19 in severely/critically ill patients.

Dynamic changes of IgM and IgG antibodies in asymptomatic patients as an effective way to detect SARS-CoV-2 infection.

BACKGROUND: COVID-19 has become a global pandemic, and close contacts and asymptomatic patients are worthy of attention. METHODS: A total of 1844 people in close contacts with 76 COVID-19 patients were investigated, and nasopharyngeal swabs and venous blood were collected for centralized medical quarantine observation. Real-time fluorescence was used to detect SARS-CoV-2 nucleic acid in nasopharyngeal swabs of all close contacts, and the colloidal gold method was used to detect serum-specific antibodies. Levels of IgM- and IgG-specific antibodies were detected quantitatively through chemiluminescence from the first nucleic acid turned negative date (0 week) and on weekly intervals of ≤1 week, 1-2 weeks, 2-3 weeks, 3-4 weeks, 4-5 weeks, 5-6 weeks, and 6-7 weeks. RESULTS: The total positive rate of the colloidal gold method (88.5%, 23/26) was significantly higher (χ2  = 59.182, p < 0.001) than that of the healthy control group (2.0%, 1/50). There was significant difference in IgG concentration at different time points (0-7 weeks) after negative nucleic acid conversion (χ2  = 14.034, p = 0.029). Serum IgG levels were significantly higher at weekly time points of 4-5 weeks (Z = -2.399, p = 0.016), 5-6 weeks (Z = -2.049, p = 0.040), and 6-7 weeks (Z = -2.197, p = 0.028) compared with 1-2 weeks after negative nucleic acid conversion. However, there was no significant difference (χ2  = 4.936, p = 0.552) in IgM concentration between time points tested (0-7 weeks) after negative nucleic acid conversion. The positive rates of IgM and IgG in asymptomatic patients (χ2  = 84.660, p < 0.001) were significantly higher than those in the healthy control group (χ2  = 9.201, p = 0.002) within 7 weeks of negative nucleic acid conversion. CONCLUSIONS: The IgG concentration in asymptomatic cases remained at a high level after nucleic acid turned negative. Nucleic acid detection combined with IgM and IgG antibody detection is an effective way to screen asymptomatic infections.

Changes of serum IL-10, IL-1ß, IL-6, MCP-1, TNF-α, IP-10 and IL-4 in COVID-19 patients.

BACKGROUND AND PURPOSE: Studies have shown that some cytokines in COVID-19 patients were elevated. This study aims to assess whether IL-10, IL-1ß, IL-6, MCP-1, TNF-α, IP-10 and IL-4 serve as potential diagnostic biomarkers of COVID-19. METHODS: The above serum cytokines in COVID-19 patients and non-COVID-19 patients were detected by ELISA and SARS-CoV-2 IgM and IgG were detected by the chemiluminescence method. The independent-sample Mann-Whitney U test was utilised to compare cytokine levels in different groups and courses, the Levene T-test and T'-test were utilised to compare they in different genders and the Spearman correlation test was utilised to analyse the correlation between the cytokine levels with ages and SARS-CoV-2 IgG and IgM. RESULTS: Serum levels of IL-10, IL-1ß, MCP-1, TNF-α and IL-4 in COVID-19 patients were significantly higher than those in non-COVID-19 patients, while IL-6 were only significantly higher than in healthy people, IP-10 were significantly lower than in other diseases patients. AUCs of COVID-19 diagnosed by IL-10, IL-1ß, IL-6, MCP-1, TNF-α, IP-10 and IL-4 were 0.735, 0.775, 0.595, 0.821, 0.848, 0.38 and 0.682, respectively. In the COVID-19 patients' serum, the levels of IL-10 and MCP-1 of male were noticeably higher than those of female, and all cytokines were significantly positively correlated with age, IL-1ß and IL-4 were significantly negatively correlated with SARS-CoV-2 IgM, while IL-10, IL-1ß, IL-6, TNF- and IP-10 were significantly negatively correlated with SARS-CoV-2 IgG. IL-10 on 43-56 days was significantly lower than at 29-42 days, TNF-α at 15-42 days was significantly higher than at 0-14 days, IP-10 at 0-14 days was the highest and IL-4 at 29-42 days was significantly higher than at 0-14 days. CONCLUSIONS: The detection of IL-10, IL-1 ß, IL-6, MCP-1, TNF-α and IL-4 would assist the clinical study of COVID-19, and IP-10 may be the cytokine of early elevation in COVID-19 patients.

Coronavirus disease 2019 in pregnancy

Objectives: This study aimed to compare clinical courses and outcomes between pregnant and reproductive-aged non-pregnant women with COVID-19, and to assess the vertical transmission potential of COVID-19 in pregnancy.

Delayed SARS-CoV-2 Clearance in Patients with Obesity.

OBJECTIVE: The present study aimed to investigate the correlation between obesity and virus persistence in patients with COVID-19. DESIGN AND METHODS: A total of 57 patients with laboratory-confirmed COVID-19 were admitted to two clinical centers, and data were analyzed retrospectively. Among them, 18 patients with body mass index (BMI) ≥ 25 kg/m2 were diagnosed with obesity, and dynamics of viral replication were compared. RESULTS: Eighteen patients were diagnosed with obesity. The correlations between BMI and white blood cell, C-reactive protein, and cycle threshold (Ct) values of ORF1ab were not significant (all P > 0.05). On day 7 after admission, virus clearance was achieved in 13 (33.3%) patients with BMI < 25 kg/m2 and 5 (27.8%) patients with BMI ≥ 25 kg/m2 (χ2 = 0.176, P =0.68). On day 14, the RNA tests were negative in 37 (94.9%) patients with BMI < 25 kg/m2 and 13 (72.2%) patients with BMI ≥ 25 kg/m2 (χ2 = 5.865, P = 0.03). Multivariable analysis showed that only BMI ≥ 25 kg/m2 (P = 0.02) was the independent risk factor for virus clearance on day 14. CONCLUSION: Obesity may affect the clearance of SARS-CoV-2, and BMI should be assessed in patients with COVID-19, although they are not seriously ill.

Sleep quality and mental health status of healthcare professionals during the outbreak of coronavirus disease 2019 (COVID-19).

To investigate the sleep quality and mental health status of healthcare professionals during the outbreak of coronavirus disease 2019 (COVID-19) in order to promote timely intervention and treatment. An Questionnaire Star of WeChat online survey was conducted at Hwamei Hospital, University of Chinese Academy of Sciences, NingBo, China. The questionnaire consisted of two parts including sociodemographic characteristics, and the Pittsburgh Sleep Quality Index (PSQI), the Generalized Anxiety Disorder (GAD-7) scale, a depression screening scale (Patient Health Questionnaire-9 [PHQ-9]) so as to investigate the sleep quality and mental health status of healthcare professionals during the outbreak of COVID-19.The data were analyzed with the t-test, χ2 test, one-way analysis of variance (ANOVA) and Pearson correlation, P < 0.05 was considered statistically significant. The mean score of PSQI is 5.8 ± 3.7 and the incidence of sleep disorders was 28.8% among the healthcare professionals and was related to occupation, title, education level, role and some underlying diseases. The positive rates for anxiety and depression among the healthcare professionals were 33.2% and 39.4% according to the GAD-7 and PHQ-9. Mental health status was related to occupation, education level, role and some underlying diseases. During the COVID-19 outbreak, sleep quality was significantly correlated with anxiety and depression among the healthcare professionals. The incidences of sleep disorder, anxiety and depression among healthcare professionals have been high. Furthermore, these disorders are interrelated and require timely intervention and treatment.

The Impact of Intolerance of Uncertainty on Test Anxiety: Student Athletes During the COVID-19 Pandemic.

Test anxiety caused by intolerance of uncertainty has a negative impact on the physical and mental health of student athletes, especially in the context of the coronavirus disease 2019 (COVID-19) pandemic. A total of 556 grade three high school student athletes in Chongqing, China, were investigated using the Test Anxiety Scale (TAS), Intolerance of Uncertainty Scale-12 (IUS-12), Perceived Social Support Scale, and Coping Style Scale for Middle School Students. Results reveal that more than half the student athletes experienced test anxiety, and the severity was above average during the COVID-19 pandemic. There was a significant correlation between intolerance of uncertainty, perceived social support, coping style, and test anxiety. A positive correlation was found between test anxiety, intolerance of uncertainty, and coping style toward emotions, and a negative correlation between test anxiety, perceived social support, and coping style toward problems. Intolerance of uncertainty has a direct predictive effect on test anxiety, and perceived social support and coping style play a chain mediator role between intolerance of uncertainty and test anxiety. By constructing the mediating effect model, we can, to some extent, reveal the mechanism of the influence of intolerance of uncertainty on test anxiety. This study has a certain reference value for the prevention of test anxiety in student athletes in the context of the COVID-19 pandemic.