V-Pods: Rapid, Sensitive Detection of Intact SARS-CoV-2 using DNA Nets and a Smartphone-Linked Fluorimeter

Rapid, simple, inexpensive, and sensitive self-testing for SARS-CoV-2 is expected to be an important element of controlling the ongoing COVID pandemic. We report a novel approach in which saliva is mixed at room temperature with a Designer DNA Nanostructure (DDN) engineered to create a net-like structure that positions an array of highly specific nucleic acid aptamer-quencher locks at the locations of the trimeric spike proteins. When the spike proteins selectively unlock aptamers on the DDN, fluorescent reporter molecules are unquenched, generating an intense and easily measured optical signal. The fluorescence intensity, proportional to the virus concentration, is detected by a battery-powered palmsized fluorimeter, whose functions are managed wirelessly with a Bluetooth-linked smartphone. Because the single-step, room temperature, test is performed in a conventional 0.2 mL PCR tube that is inserted into the fluorimeter, which resembles an Apple AirPodsT headphone case, we call the technology (DDN+fluorimeter+App) a "V-Pod." We show that DDNs are highly specific only for detection of SARS-CoV-2 in both its initial form as well as common variants. The approach achieves a detection limit of 10,000 genome copies/mL, consistent with laboratory-based PCR, while requiring only one reagent and a 5-10 minute incubation time with saliva. Because DDNs are inexpensively synthesized, structurally stable nucleic acid constructs, and the V-Pod instrument is comprised of inexpensive electronic and photonic components, the approach offers potential for rapid self-monitoring of viral infection with integrated capability for contact tracing and interaction with health services.

Impact of COVID-19 on acute ischemic stroke presentation and prognosis in a county-level stroke center.

OBJECTIVE: The COVID-19 pandemic has influenced regular medical procedures and health-seeking behaviors. In this study, we aimed to investigate the influence of the COVID-19 pandemic on the presentation and prognosis of acute ischemic stroke (AIS) patients in county-level stroke centers. PATIENTS AND METHODS: We retrospectively collected AIS patients during the strict lockdown period (January 24, 2020, to March 27, 2020) and the corresponding "new normal" period (2021) of the COVID-19 pandemic. Patients seen during the same timeframe in 2019 were enrolled as controls. Statistical analysis was conducted to compare the clinical characteristics of AIS patients who presented during the lockdown and new normal periods and those who presented during the pre-COVID-19 pandemic period. RESULTS: A total of 134 AIS patients presented during the lockdown period (the 2020 group), 207 patients in the pre-COVID-19 period (the 2019 group) and 201 patients in the "new normal" period (the 2021 group). Compared to the 2019 group, there was approximately 1/3 reduction in the number of patients who presented during the lockdown period, while the number of patients who received IVT or EVT was similar between the two groups. The number of patients, baseline characteristics, workflow intervals and clinical outcomes presented during the "new normal" period were similar between the 2019 and 2021 groups. Logistic regression showed that lockdown or new normal status were not risk factors associated with a poor outcome at 90 days. CONCLUSIONS: In county-level city stroke centers, the COVID-19 lockdown resulted in a reduction in the number of patients with AIS admitted to the hospital but had no effect on patients treated with IVT or EVT. Lockdown or new normal status did not influence the prognosis of AIS patients.

Disulfiram blocked cell entry of SARS-CoV-2 via inhibiting the interaction of spike protein and ACE2

Disulfiram is an FDA-approved drug that has been used to treat alcoholism and has demonstrated a wide range of anti-cancer, anti-bacterial, and anti-viral effects. In the global COVID-19 pandemic, there is an urgent need for effective therapeutics and vaccine development. According to recent studies, disulfiram can act as a potent SARS-CoV-2 replication inhibitor by targeting multiple SARS-CoV-2 non-structural proteins to inhibit viral polyprotein cleavage and RNA replication. Currently, disulfiram is under evaluation in phase II clinical trials to treat COVID-19. With more and more variants of the SARS-CoV-2 worldwide, it becomes critical to know whether disulfiram can also inhibit viral entry into host cells for various variants and replication inhibition. Here, molecular and cellular biology assays demonstrated that disulfiram could interrupt viral spike protein binding with its receptor ACE2. By using the viral pseudo-particles (Vpps) of SARS-CoV-2, disulfiram also showed the potent activity to block viral entry in a cell-based assay against Vpps of different SARS-CoV-2 variants. We further established a live virus model system to support the anti-viral entry activity of disulfiram with the SARS-CoV-2 virus. Molecular docking revealed how disulfiram hindered the binding between the ACE2 and wild-type or mutated spike proteins. Thus, our results indicate that disulfiram has the capability to block viral entry activity of different SARS-CoV-2 variants. Together with its known anti-replication of SARS-CoV-2, disulfiram may serve as an effective therapy against different SARS-CoV-2 variants.

[Psychological and behavioral functioning of children and adolescents during long-term home-schooling].

Objective: To study the characteristics and risk factors of psychological and behavioral problems of children and adolescents of different ages and genders in long-term home-schooling during the coronavirus disease-2019 pandemic. Further, to provide scientific basis for more targeted psychological intervention and coping strategies in the future. Methods: A cross-sectional survey using an online questionnaire was conducted on students aged 6-16 years old in five representative cities of North (Beijing), East (Shanghai), West (Chongqing), South (Guangzhou) and Middle (Wuhan) in China. In this study, the social behavior and psychological abnormalities which was defined as the positive of any dimension were investigated in multiple dimensions during long-term home-schooling. The influencing factors of psycho-behavioral problems were analyzed by Logistic regression, and the confounding factors were corrected with graded multivariable adjustment. Results: A total of 6 906 valid questionnaires were collected including 3 592 boys and 3 314 girls, of whom 3 626 were children (6-11 years old) and 3 280 were adolescents (12-16 years old). The positive detection rate of psychosocial-behavioral problems were 13.0% (900/6 906) totally, 9.6% (344/3 592) in boys and 16.8% (556/3 314) in girls respectively, and 7.3%(142/1 946) in boys aged 6-11, 14.0%(235/1 680) in girls aged 6-11, 12.3%(202/1 646) in boys aged 12-16, 19.6%(321/1 634) in girls aged 12-16 respectively. There were significant differences between the psychological problems group and the non-psychological problems group in gender, parent-offspring conflict, number of close friends, family income change, sedentary time, homework time, screen exposure time, physical activity, dietary problems (χ²=78.851, 285.264, 52.839, 26.284, 22.778, 11.024, 10.688, 36.814, 70.982, all P<0.01). The most common symptoms in boys aged 6-11 years were compulsive activity, schizoid and depression, in girls aged 6-11 years were schizoid/compulsive activity, hyperactivity and social withdrawal, in boys aged 12-16 years were hyperactivity, compulsive activity and aggressive behavior, and in girls aged 12-16 years were schizoid, anxiety/compulsive activity and depression/withdrawal, respectively. After graded multivariable adjustment, besides the common risk factors, homework time and online study time were the risk factors of 6-11 years old groups [boys OR(95%CI): 1.750 (1.32-2.32), 1.214(1.00-1.47), girls: 1.579(1.25-1.99), 1.222(1.05-1.42), all P<0.05], videogames time were the risk factors of 12-16 years old groups [ boys: 2.237 (1.60-3.13), girls: 1.272 (1.00-1.61), all P<0.05]. Conclusions: Some children and adolescents may have psychological and behavioral problems during long-term home-schooling. The psychological and behavioral manifestations differed in age and gender subgroups, which deserve special attention in each subgroups. Schools, families and specialists should actively provide precise psychological support and comprehensive intervention strategies according to special features and risk factors.

Airway management in a critically ill patient with novel coronavirus pneumonia undergoing extracorporeal membrane oxygenation

This article summarizes the nursing experience in a critically ill patient with novel coronavirus pneumonia after extracorporeal membrane oxygenation (ECMO) treatment for lung function improvement. After oral intubation-assisted ventilation, anti-infection, and other symptomatic support treatments, the patient was still unable to breathe without the ventilator. For the sustained carbon dioxide retention and severe gas exchange impairment, he was treated with tracheotomy and ECMO. During the treatment, a series of nursing measures to improve lung function were adopted, such as sputum suction care, atomized inhalation therapy, bronchial irrigation, and lateral ventilation combined with postural drainage. After 7 days of ECMO treatment and nursing, the patient's lung function improved and then he was weaned from the machine.

[Laboratory testing, prevention and control of asymptomatic carriers of coronavirus disease 2019].

With many hard efforts, the epidemic prevention and control work in China has borne successful, accelerating the gradual restoration of production, living order and routine medical work. However, there is increasing evidence that many patients with COVID-19 are asymptomatic, but they are potential transmitter of the virus. There are difficulties in screening for asymptomatic infections, which makes it more difficult for national prevention and control of this epidemic. Therefore, it is urgent to develop better screening and laboratory testing for asymptomatic infections with COVID-19 with high speed, sensitivity and specificity. It is also important to improve our risk assessment, prevention and control strategies to further prevent the spread of the epidemic.

[Exploration and application of a novel attempt to recruit participants in clinical trials of vaccines under the emergency].

Objective: To evaluate and share the novel method for recruiting participants in clinical trials of vaccines in emergency situations. Methods: To publish recruitment notice in local areas of Wuhan through websites and medium, and guide interested persons to log in to the"Clinical Trials of SARS-CoV-2 Vaccine Reservation and Health Declaration System"to appoint and register their health information. The "Health Declaration System" provides each volunteer evaluation and risk levels to preliminarily exclude those who do not meet the inclusion criteria. Researchers review the qualified volunteers by telephone, organize them to go to the vaccination site, and finally conduct a strict medical screening to determine the final subjects. Results: A total of 4 819 people and 5 132 people registered in the Phase Ⅰ and Phase Ⅱ recruitment system respectively, with men 2 912 (60.43%) and 2 887 (56.25%) more than women 1 907 (39.57%) and 2 245 (43.75%), mostly in the 20-39 age group, with 3 211 (66.63%) and 3 966 (77.28%). All 13 districts in Wuhan have interested residents to participate clinical research.The initial qualified rate of the Phase Ⅱ recruitment system was higher than that of Phase Ⅰ, with men 2 047 (70.28%) and 2 135(73.95%), higher than women 1 083 (56.80%) and 1 472 (65.57%); 440 and 689 people were reviewed by telephone in Phase Ⅰ and Phase Ⅱ respectively, and the number of verified volunteers was about 440 (35.00%) and 689 (67.20%); Of the 201 603 people who arrived at the vaccination site, 12 and 26 of them were positive for the SARS-CoV-2 antibody with an antibody positive rate of 6.00% and 4.31% respectively. Conclusion: The novel method for recruiting subjects in this clinical study is efficient and reliable, and the recruitment situation of Phase Ⅰ had set a good example for Phase Ⅱ but the medium-and long-term compliance of subjects and the separation of willingness and behaviors still need to be further studied.