Mechanistic investigation of direct photodegradation of chloroquine phosphate under simulated sunlight.

Chloroquine phosphate (CQ) is an antiviral drug for Coronavirus Disease 2019 and an old drug for treatment of malaria, which has been detected in natural waters. Despite its prevalence, the environmental fate of CQ remains unclear. In this study, the direct photodegradation of CQ under simulated sunlight was investigated. The effect of various parameters such as pH, initial concentration and environmental matrix were examined. The photodegradation quantum yield of CQ (4.5 × 10-5-0.025) increased with the increasing pH value in the range of 6.0-10.0. The electron spin resonance (ESR) spectrometry and quenching experiments verified that the direct photodegradation of CQ was primarily associated with excited triplet states of CQ (3CQ*). The common ions had negligible effect and humic substances exhibited a negative effect on CQ photodegradation. The photoproducts were identified using high-resolution mass spectrometry and the photodegradation pathway of CQ was proposed. The direct photodegradation of CQ involved the cleavage of the C-Cl bond and substitution of the hydroxyl group, followed by further oxidation to yield carboxylic products. The photodegradation processes were further confirmed by the density functional theory (DFT) computation for the energy barrier of CQ dichlorination. The findings contribute to the assessment of the ecological risk associated with the overuse of Coronavirus drugs during global public health emergencies.

Paediatric healthcare and hospital worker SARS-CoV-2 IgG antibody: A longitudinal cohort study.

Background: This study sought to determine the prevalence of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) nucleocapsid (N) and spike (S) protein immunoglobulin G (IgG) antibodies in healthcare and hospital workers (HCHWs), and changes in IgG N antibody levels over time. Methods: Longitudinal study of HCHWs at a freestanding, urban paediatric tertiary care hospital. Asymptomatic HCHWs aged ≥18 years working in clinical areas were eligible to enrol. Participants completed four surveys and blood draws over 12 months. Specimens were tested for IgG N at four timepoints and IgG S at 12 months. Results: In total, 531 HCHWs enrolled in this study; of these, 481 (91%), 429 (81%) and 383 (72%) completed follow-up blood draws at 2, 6 and 12 months, respectively. Five of 531 (1%), 5/481 (1%), 6/429 (1%) and 5/383 (1.3%) participants were seropositive for IgG N at baseline, 2, 6 and 12 months, respectively. All (374/374; 100%) participants who received one or two doses of either mRNA COVID-19 vaccine were seropositive for IgG S. One of nine unvaccinated participants was seropositive for IgG S. Conclusions: In this paediatric hospital, IgG N and IgG S were detected in 1.9% and 97.9% of HCHWs, respectively. This study demonstrated low transmission of SARS-CoV-2 among HCHWs with appropriate infection prevention measures.

Rapid detection of intact SARS-CoV-2 using designer DNA nets and a pocket-size smartphone-linked fluorimeter

Rapid, sensitive, and inexpensive point-of-care diagnosis is vital to controlling highly infectious diseases, including COVID-19. Here, we report the design and characterization of a compact fluorimeter called a "Virus Pod” (V-Pod) that enables sensitive self-testing of SARS-CoV-2 viral load in saliva. The rechargeable battery-operated device reads the fluorescence generated by Designer DNA Nanostructures (DDN) when they specifically interact with intact SARS-CoV-2 virions. DDNs are net-shaped self-assembling nucleic acid constructs that provide an array of highly specific aptamer-fluorescent quencher duplexes located at precise positions that match the pattern of spike proteins. The room-temperature assay is performed by mixing the test sample with DNA Net sensor in a conventional PCR tube and placing the tube into the V-Pod. Fluorescent signals are generated when multivalent aptamer-spike binding releases fluorescent quenchers, resulting in rapid (5-min) generation of dose-dependent output. The V-Pod instrument performs laser excitation, fluorescence intensity quantitation, and secure transmission of data to an App via Bluetooth™. We show that the V-Pod and DNA Net assay achieves clinically relevant detection limits of 3.92 × 103 viral-genome-copies/mL for pseudo-typed wild-type SARS-CoV-2 and 1.84 × 104, 9.69 × 104, 6.99 × 104 viral-genome-copies/mL for pathogenic Delta, Omicron, and D614G variants, representing sensitivity similar to laboratory-based PCR. The pocket-sized instrument (∼$294), inexpensive reagent-cost/test ($1.26), single-step, rapid sample-to-answer, and quantitative output represent a capability that is compatible with the needs of frequent self-testing in a consumer-friendly format that can link with medical service systems such as healthcare providers, contact tracing, and infectious disease reporting.

Rapid detection of intact SARS-CoV-2 using designer DNA Nets and a pocket-size smartphone-linked fluorimeter.

Rapid, sensitive, and inexpensive point-of-care diagnosis is vital to controlling highly infectious diseases, including COVID-19. Here, we report the design and characterization of a compact fluorimeter called a "Virus Pod" (V-Pod) that enables sensitive self-testing of SARS-CoV-2 viral load in saliva. The rechargeable battery-operated device reads the fluorescence generated by Designer DNA Nanostructures (DDN) when they specifically interact with intact SARS-CoV-2 virions. DDNs are net-shaped self-assembling nucleic acid constructs that provide an array of highly specific aptamer-fluorescent quencher duplexes located at precise positions that match the pattern of spike proteins. The room-temperature assay is performed by mixing the test sample with DNA Net sensor in a conventional PCR tube and placing the tube into the V-Pod. Fluorescent signals are generated when multivalent aptamer-spike binding releases fluorescent quenchers, resulting in rapid (5-min) generation of dose-dependent output. The V-Pod instrument performs laser excitation, fluorescence intensity quantitation, and secure transmission of data to an App via Bluetooth™. We show that the V-Pod and DNA Net assay achieves clinically relevant detection limits of 3.92 × 103 viral-genome-copies/mL for pseudo-typed wild-type SARS-CoV-2 and 1.84 × 104, 9.69 × 104, 6.99 × 104 viral-genome-copies/mL for pathogenic Delta, Omicron, and D614G variants, representing sensitivity similar to laboratory-based PCR. The pocket-sized instrument (∼$294), inexpensive reagent-cost/test ($1.26), single-step, rapid sample-to-answer, and quantitative output represent a capability that is compatible with the needs of frequent self-testing in a consumer-friendly format that can link with medical service systems such as healthcare providers, contact tracing, and infectious disease reporting.

LitCovid ensemble learning for COVID-19 multi-label classification.

The Coronavirus Disease 2019 (COVID-19) pandemic has shifted the focus of research worldwide, and more than 10 000 new articles per month have concentrated on COVID-19-related topics. Considering this rapidly growing literature, the efficient and precise extraction of the main topics of COVID-19-relevant articles is of great importance. The manual curation of this information for biomedical literature is labor-intensive and time-consuming, and as such the procedure is insufficient and difficult to maintain. In response to these complications, the BioCreative VII community has proposed a challenging task, LitCovid Track, calling for a global effort to automatically extract semantic topics for COVID-19 literature. This article describes our work on the BioCreative VII LitCovid Track. We proposed the LitCovid Ensemble Learning (LCEL) method for the tasks and integrated multiple biomedical pretrained models to address the COVID-19 multi-label classification problem. Specifically, seven different transformer-based pretrained models were ensembled for the initialization and fine-tuning processes independently. To enhance the representation abilities of the deep neural models, diverse additional biomedical knowledge was utilized to facilitate the fruitfulness of the semantic expressions. Simple yet effective data augmentation was also leveraged to address the learning deficiency during the training phase. In addition, given the imbalanced label distribution of the challenging task, a novel asymmetric loss function was applied to the LCEL model, which explicitly adjusted the negative-positive importance by assigning different exponential decay factors and helped the model focus on the positive samples. After the training phase, an ensemble bagging strategy was adopted to merge the outputs from each model for final predictions. The experimental results show the effectiveness of our proposed approach, as LCEL obtains the state-of-the-art performance on the LitCovid dataset. Database URL: https://github.com/JHnlp/LCEL.

A photonic resonator interferometric scattering microscope for label-free detection of nanometer-scale objects with digital precision in point-of-use environments.

Label-free detection and digital counting of nanometer-scaled objects such as nanoparticles, viruses, extracellular vesicles, and protein molecules enable a wide range of applications in cancer diagnostics, pathogen detection, and life science research. Here, we report the design, implementation, and characterization of a compact Photonic Resonator Interferometric Scattering Microscope (PRISM) designed for point-of-use environments and applications. The contrast of interferometric scattering microscopy is amplified through a photonic crystal surface, upon which scattered light from an object combines with illumination from a monochromatic source. The use of a photonic crystal substrate for interferemetric scattering microscopy results in reduced requirements for high-intensity lasers or oil-immersion objectives, thus opening a pathway toward instruments that are more suitable for environments outside the optics laboratory. The instrument incorporates two innovative elements that facilitate operation on a desktop in ordinary laboratory environments by users that do not have optics expertise. First, because scattering microscopes are extremely sensitive to vibration, we incorporated an inexpensive but effective solution of suspending the instrument's main components from a rigid metal framework using elastic bands, resulting in an average of 28.7 dBV reduction in vibration amplitude compared to an office desk. Second, an automated focusing module based on the principle of total internal reflection maintains the stability of image contrast over time and spatial position. In this work, we characterize the system's performance by measuring the contrast from gold nanoparticles with diameters in the 10-40 nm range and by observing various biological analytes, including HIV virus, SARS-CoV-2 virus, exosome, and ferritin protein.

Understanding hispanic patient satisfaction with telehealth during COVID-19.

BACKGROUND: Recent studies have described the use of telehealth for pediatric surgical care during the COVID-19 pandemic. We aimed to evaluate equity in telehealth use by comparing rates of utilization and satisfaction with pediatric surgical telemedicine among Hispanic patients. METHODS: We conducted a retrospective cohort study of patients seen by a surgical subspecialty provider in the outpatient setting at a quaternary pediatric hospital between April 1 and June 30, 2020. Patients evaluated in the same three-month period in 2019 were analyzed as a historic control. Differences in Family Experience Survey (FES) responses based on race and ethnicity and preferred language of care were assessed using univariable and multivariable generalized linear modeling. RESULTS: The pandemic cohort included fewer patients of Hispanic ethnicity and fewer Spanish-speakers. After controlling for visit type, comparison of Spanish-speaking and English-speaking patients revealed that Spanish-speaking families had significantly lower scores for FES items that evaluated healthcare provider explaining (IRR 0.74, 95% CI: 0.61-0.90), listening (IRR 0.76, 95% CI: 0.63-0.92), and time spent with the family (IRR 0.73, 95% CI: 0.60-0.89). There were no differences in FES responses based on insurance status or degree of medical complexity. CONCLUSIONS: Telehealth services were less commonly used among Hispanic and Spanish-speaking patients. Language may differentially affect family satisfaction with healthcare and telehealth solutions. Strategies to mitigate these inequities are needed and may include strengthening interpreter services and providing language-concordant care. LEVEL OF EVIDENCE: Level IV.

Review of HIV Self Testing Technologies and Promising Approaches for the Next Generation.

The ability to self-test for HIV is vital to preventing transmission, particularly when used in concert with HIV biomedical prevention modalities, such as pre-exposure prophylaxis (PrEP). In this paper, we review recent developments in HIV self-testing and self-sampling methods, and the potential future impact of novel materials and methods that emerged through efforts to develop more effective point-of-care (POC) SARS-CoV-2 diagnostics. We address the gaps in existing HIV self-testing technologies, where improvements in test sensitivity, sample-to-answer time, simplicity, and cost are needed to enhance diagnostic accuracy and widespread accessibility. We discuss potential paths toward the next generation of HIV self-testing through sample collection materials, biosensing assay techniques, and miniaturized instrumentation. We discuss the implications for other applications, such as self-monitoring of HIV viral load and other infectious diseases.

The changes in psychological symptoms of COVID-19 patients after "re-positive".

Background: Previous studies have showed that individuals infected with COVID-19 were more likely to report psychological symptoms. However, little is known about the changes from testing positive to negative to positive again. Methods: This survey was conducted through the questionnaires including the 7-item Generalized Anxiety Disorder (GAD-7), the 9-item Patient Health Questionnaire (PHQ-9), as well as the Self-Rating Scale of Sleep (SRSS) to explore the psychological status of COVID-19 and re-positive cases.″re-positive″ is defined as a positive RT-PCR test at any time during the recovery period after testing negative. Results: A total of 94 COVID-19 patients presented the prevalence rates of anxiety, depression, insomnia, and any of the three psychological symptoms being 26.6, 8.6, 12.8, and 31.9%, respectively. Among these, 32 cases were re-tested positive during the recovery period, with the prevalence rates of anxiety, depression, insomnia, and any of the three psychological symptoms being 21.9, 18.7, 31.2, and 37.5%, respectively. The psychological status after re-positive showed a significant decrease in anxiety (P = 0.023), an increase in depression, and a significant rise in insomnia (P = 0.035). For those with no psychological symptoms during initial-positive, after re-positive, 5.88% reported anxiety, 5.88% reported depression, and 11.76% reported insomnia. For those who experienced only anxiety symptoms during initial-positive, after re-positive, 33.3% reported depression, and 33.3% reported insomnia. Conclusions: Our findings encompassed the urgent concern for anxiety in initial-positive COVID-19 patients, depression in re-positive COVID-19 patients, and insomnia in both initial and re-positive patients, hence enabling targeted interventions for appeasing the psychological burden of COVID-19 patients.

Altered gut microbiota composition in children and their caregivers infected with the SARS-CoV-2 Omicron variant.

BACKGROUND: Gut microbiota alterations have been implicated in the pathogenesis of coronavirus disease 2019 (COVID-19). This study aimed to explore gut microbiota changes in a prospective cohort of COVID-19 children and their asymptomatic caregivers infected with the severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2) Omicron variant. METHODS: A total of 186 participants, including 59 COVID-19 children, 50 asymptomatic adult caregivers, 52 healthy children (HC), and 25 healthy adults (HA), were recruited between 15 April and 31 May 2022. The gut microbiota composition was determined by 16S rRNA gene sequencing in fecal samples collected from the participants. Gut microbiota functional profiling was performed by using Phylogenetic Investigation of Communities by Reconstruction of Unobserved States (PICRUSt) software. RESULTS: The gut microbiota analysis of beta diversity revealed that the fecal microbial community of COVID-19 children remained far distantly related to HC. The relative abundances of the phyla Actinobacteria and Firmicutes were decreased, whereas Bacteroidetes, Proteobacteria, and Verrucomicrobiota were increased in COVID-19 children. Feces from COVID-19 children exhibited notably lower abundances of the genera Blautia, Bifidobacterium, Fusicatenibacter, Streptococcus, and Romboutsia and higher abundances of the genera Prevotella, Lachnoclostridium, Escherichia-Shigella, and Bacteroides than those from HC. The enterotype distributions of COVID-19 children were characterized by a high prevalence of enterotype Bacteroides. Similar changes in gut microbiota compositions were observed in asymptomatic caregivers. Furthermore, the microbial metabolic activities of KEGG (Kyoto Encyclopedia of Genes and Genomes) and COG (cluster of orthologous groups of proteins) pathways were perturbed in feces from subjects infected with the SARS-CoV-2 Omicron variant. CONCLUSION: Our data reveal altered gut microbiota compositions in both COVID-19 children and their asymptomatic caregivers infected with the SARS-CoV-2 Omicron variant, which further implicates the critical role of gut microbiota in COVID-19 pathogenesis.

Clinical characteristics of persons infected with imported SARS-CoV-2 omicron variant in Tianjin

Objective: To investigate the epidemiological, clinical and imaging characteristics of SARS-CoV-2 infection caused by Omicron variant.

Effect of corticosteroids in patients with COVID-19: a Bayesian network meta-analysis.

OBJECTIVES: We sought to perform a network meta-analysis to compare the safety and efficacy of the systemic administration of corticosteroids for the treatment of COVID-19. METHODS: A Bayesian network meta-analysis was performed to combine the direct and indirect evidence. The surface under the cumulative ranking curve was obtained to estimate the ranking probability of the treatment agents for each outcome. The efficacy outcome was 28-day all-cause mortality. The safety outcome was serious adverse events. RESULTS: A total of 16 trials with 2992 patients comparing four treatments (dexamethasone, hydrocortisone, methylprednisolone, and placebo) were identified. Direct analysis showed that corticosteroids were associated with a reduced risk of 28-day mortality compared with usual care (risk ratio [RR] 0.83; 95% confidence interval [CrI] 0.70-0.99). Network analysis showed that the pooled RR was 0.63 (95% CrI 0.39-0.93) for all-cause mortality at 28 days comparing methylprednisolone with usual care or placebo (surface under the cumulative ranking curve: 91%). Our analysis demonstrated that patients who received a low dose of corticosteroids (RR 0.80; 95% CrI 0.70-0.91) and a long course of treatment (RR 0.81; 95% CrI 0.71-0.91) had higher survival rates than patients in the placebo group. CONCLUSION: Administration of corticosteroids was associated with a reduced all-cause mortality at 28 days compared with placebo or usual care. Our analysis also confirmed the mortality benefit associated with low-dose and long-term treatment with corticosteroids.

Impact of COVID-19 lockdown on match performances in the National Basketball Association

This study aimed to compare differences in the match performances between home and away games during pre- and post-COVID-19 lockdown and to identify the key factors to match success with and without spectators. The sample consisted of 1,549 basketball matches including 971 games of the 2019–2020 regular season before the COVID-19 lockdown and 578 ghost matches of the 2020–2021 regular season after the COVID-19 pandemic. The independent t-test was used to explore the differences before and after COVID-19 while univariate and multivariable logistic regression models were used to identify the key factors to match success between matches with and without spectators. Our study identified that offensive rebounds were the only indicator differentiating between home and away games after the COVID-19 lockdown. Furthermore, home teams won more matches than away matches before the COVID-19 whereas home advantage had no impact on winning matches after the COVID-19. Our study suggested that crowd support may play a key role in winning games in the NBA. Furthermore, independently of the pre-and post-COVID19 pandemic, free throws made, three-point field goals made, defensive rebounds, assists, steals, personal fouls, and opponent quality were key factors differentiating between win and loss. Coaches and coaching staff can make informed decisions and well prepare for basketball match strategies.

Meet changes with constancy: Defence, antagonism, recovery, and immunity roles of extracellular vesicles in confronting SARS-CoV-2.

Coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has wrought havoc on the world economy and people's daily lives. The inability to comprehensively control COVID-19 is due to the difficulty of early and timely diagnosis, the lack of effective therapeutic drugs, and the limited effectiveness of vaccines. The body contains billions of extracellular vesicles (EVs), which have shown remarkable potential in disease diagnosis, drug development, and vaccine carriers. Recently, increasing evidence has indicated that EVs may participate or assist the body in defence, antagonism, recovery and acquired immunity against SARS-CoV-2. On the one hand, intercepting and decrypting the general intelligence carried in circulating EVs from COVID-19 patients will provide an important hint for diagnosis and treatment; on the other hand, engineered EVs modified by gene editing in the laboratory will amplify the effectiveness of inhibiting infection, replication and destruction of ever-mutating SARS-CoV-2, facilitating tissue repair and making a better vaccine. To comprehensively understand the interaction between EVs and SARS-CoV-2, providing new insights to overcome some difficulties in the diagnosis, prevention and treatment of COVID-19, we conducted a rounded review in this area. We also explain numerous critical challenges that these tactics face before they enter the clinic, and this work will provide previous 'meet change with constancy' lessons for responding to future similar public health disasters. Extracellular vesicles (EVs) provide a 'meet changes with constancy' strategy to combat SARS-CoV-2 that spans defence, antagonism, recovery, and acquired immunity. Targets for COVID-19 diagnosis, therapy, and prevention of progression may be found by capture of the message decoding in circulating EVs. Engineered and biomimetic EVs can boost effects of the natural EVs, especially anti-SARS-CoV-2, targeted repair of damaged tissue, and improvement of vaccine efficacy.

Anxiety, Depression, and PTSD among College Students in the Post-COVID-19 Era: A Cross-Sectional Study.

In the post-COVID-19 era, significant changes have taken place regarding the epidemic, the economy, family and social life. However, it remains unclear how these changes encompass the psychological symptoms of college students. We carried out a cross-sectional study to investigate anxiety, depression, and post-traumatic stress disorder (PTSD) symptoms among college students from 10 November 2020, to 16 November 2020. The questionnaire included a self-designed canvas, Generalized Anxiety Disorder 7 (GAD-7), Patient Health Questionnaire 9 (PHQ-9), and Impact of Event Scale (IES-R). Factors associated with psychological symptoms were estimated by ordered and non-conditional logistic regression analysis. Of 4754 participants, 25.0%, 29.7%, 3.4%, 15.3%, 17.1%, and 2.9% reported anxiety, depression, PTSD symptoms, one, any two, and all three, respectively. In cases with anxiety or depression symptoms, there was a 9.11% comorbidity with PTSD. Factors associated with fears of being infected, social, family, and economic changes increased the risk of psychological symptoms in college students caused by COVID-19. Female college students, identified with anxiety or depression symptoms, were at a lower risk of developing PTSD symptoms (OR, 0.61, 95% CI: 0.43-0.86). Non-medical majors at university, rural residence, higher educational background, fear of taking public transport, and deterioration of family relationships increased the risk for PTSD symptoms among male respondents with anxiety or depression symptoms due to COVID-19. Factors correlated with psychological symptoms had expanded from the fear of being infected to extensive social, family, and economic changes caused by COVID-19. Therefore, screening and interventions for psychological symptoms should be consistently strengthened and more targeted to college students in the post-COVID-19 era.

The changes in psychological symptoms of COVID-19 patients after “re-positive”

Background Previous studies have showed that individuals infected with COVID-19 were more likely to report psychological symptoms. However, little is known about the changes from testing positive to negative to positive again. Methods This survey was conducted through the questionnaires including the 7-item Generalized Anxiety Disorder (GAD-7), the 9-item Patient Health Questionnaire (PHQ-9), as well as the Self-Rating Scale of Sleep (SRSS) to explore the psychological status of COVID-19 and re-positive cases. ″re-positive″ is defined as a positive RT-PCR test at any time during the recovery period after testing negative. Results A total of 94 COVID-19 patients presented the prevalence rates of anxiety, depression, insomnia, and any of the three psychological symptoms being 26.6, 8.6, 12.8, and 31.9%, respectively. Among these, 32 cases were re-tested positive during the recovery period, with the prevalence rates of anxiety, depression, insomnia, and any of the three psychological symptoms being 21.9, 18.7, 31.2, and 37.5%, respectively. The psychological status after re-positive showed a significant decrease in anxiety (P = 0.023), an increase in depression, and a significant rise in insomnia (P = 0.035). For those with no psychological symptoms during initial-positive, after re-positive, 5.88% reported anxiety, 5.88% reported depression, and 11.76% reported insomnia. For those who experienced only anxiety symptoms during initial-positive, after re-positive, 33.3% reported depression, and 33.3% reported insomnia. Conclusions Our findings encompassed the urgent concern for anxiety in initial-positive COVID-19 patients, depression in re-positive COVID-19 patients, and insomnia in both initial and re-positive patients, hence enabling targeted interventions for appeasing the psychological burden of COVID-19 patients.

Net-Shaped DNA Nanostructures Designed for Rapid/Sensitive Detection and Potential Inhibition of the SARS-CoV-2 Virus.

We present a net-shaped DNA nanostructure (called "DNA Net" herein) design strategy for selective recognition and high-affinity capture of intact SARS-CoV-2 virions through spatial pattern-matching and multivalent interactions between the aptamers (targeting wild-type spike-RBD) positioned on the DNA Net and the trimeric spike glycoproteins displayed on the viral outer surface. Carrying a designer nanoswitch, the DNA Net-aptamers release fluorescence signals upon virus binding that are easily read with a handheld fluorimeter for a rapid (in 10 min), simple (mix-and-read), sensitive (PCR equivalent), room temperature compatible, and inexpensive (∼$1.26/test) COVID-19 test assay. The DNA Net-aptamers also impede authentic wild-type SARS-CoV-2 infection in cell culture with a near 1 × 103-fold enhancement of the monomeric aptamer. Furthermore, our DNA Net design principle and strategy can be customized to tackle other life-threatening and economically influential viruses like influenza and HIV, whose surfaces carry class-I viral envelope glycoproteins like the SARS-CoV-2 spikes in trimeric forms.

Multi-probe attention neural network for COVID-19 semantic indexing.

BACKGROUND: The COVID-19 pandemic has increasingly accelerated the publication pace of scientific literature. How to efficiently curate and index this large amount of biomedical literature under the current crisis is of great importance. Previous literature indexing is mainly performed by human experts using Medical Subject Headings (MeSH), which is labor-intensive and time-consuming. Therefore, to alleviate the expensive time consumption and monetary cost, there is an urgent need for automatic semantic indexing technologies for the emerging COVID-19 domain. RESULTS: In this research, to investigate the semantic indexing problem for COVID-19, we first construct the new COVID-19 Semantic Indexing dataset, which consists of more than 80 thousand biomedical articles. We then propose a novel semantic indexing framework based on the multi-probe attention neural network (MPANN) to address the COVID-19 semantic indexing problem. Specifically, we employ a k-nearest neighbour based MeSH masking approach to generate candidate topic terms for each input article. We encode and feed the selected candidate terms as well as other contextual information as probes into the downstream attention-based neural network. Each semantic probe carries specific aspects of biomedical knowledge and provides informatively discriminative features for the input article. After extracting the semantic features at both term-level and document-level through the attention-based neural network, MPANN adopts a linear multi-view classifier to conduct the final topic prediction for COVID-19 semantic indexing. CONCLUSION: The experimental results suggest that MPANN promises to represent the semantic features of biomedical texts and is effective in predicting semantic topics for COVID-19 related biomedical articles.

COVID-19: Presumed Infection Routes and Psychological Impact on Staff in Administrative and Logistics Departments in a Designated Hospital in Wuhan, China.

Objective: Our aim was to explore the presumed infection routes and psychological impact of COVID-19 on staff in administrative and logistics departments (ALDs). Methods: We gathered data from all 18 staff members with COVID-19 in ALDs in Zhongnan Hospital of Wuhan University, China. The baseline, job before diagnosis, presumed infection environment, use of protective equipment, and psychological status before and after diagnosis were collected and analyzed. A total of 18 uninfected staff members working alongside them in the same environment and 18 random matched infected doctors and nurses formed two control groups; the psychological impact of these three groups was then compared. Results: Of the 18 members of staff, 88.89% were infected due to the working environment (hospital), and nine had face-to-face conversations with doctors and nurses in their daily work. Many staff members did not take any protective measures in their routine work. Before they were diagnosed, 12 staff members were aware of the seriousness of the epidemic, and most of the staff maintained a neutral attitude to the COVID-19 outbreak. A total of 77.78% of the staff experienced psychological stress or emotional changes after diagnosis, which were mainly caused by family health and disease related issues. Most of them managed their emotions by self-control and video calls with their families. There was no significant difference in psychological impact among the three groups, but uninfected staff members were fully aware of the seriousness of the epidemic. Conclusions: Effective protective measures should be taken for staff members in ALDs. Psychological interventions are very important to help infected staff members in ALDs cope with psychological distress.

Aptamers for Viral Detection and Inhibition.

Recent times have experienced more than ever the impact of viral infections in humans. Viral infections are known to cause diseases not only in humans but also in plants and animals. Here, we have compiled the literature review of aptamers selected and used for detection and inhibition of viral infections in all three categories: humans, animals, and plants. This review gives an in-depth introduction to aptamers, different types of aptamer selection (SELEX) methodologies, the benefits of using aptamers over commonly used antibody-based strategies, and the structural and functional mechanism of aptasensors for viral detection and therapy. The review is organized based on the different characterization and read-out tools used to detect virus-aptasensor interactions with a detailed index of existing virus-targeting aptamers. Along with addressing recent developments, we also discuss a way forward with aptamers for DNA nanotechnology-based detection and treatment of viral diseases. Overall, this review will serve as a comprehensive resource for aptamer-based strategies in viral diagnostics and treatment.