Equipment-free, salt-mediated immobilization of nucleic acids for nucleic acid lateral flow assays.

As the world has been facing several deadly virus crises, including Zika virus disease, Ebola virus disease, severe acute respiratory syndrome (SARS), Middle East respiratory syndrome (MERS), and Coronavirus disease 2019 (COVID-19), lateral flow assays (LFAs), which require minimal equipment for point-of-care of viral infectious diseases, are garnering much attention. Accordingly, there is an increasing demand to reduce the time and cost required for manufacturing LFAs. The current study introduces an equipment-free method of salt-mediated immobilization of nucleic acids (SAIoNs) for LFAs. Compared to general DNA immobilization methods such as streptavidin-biotin, UV-irradiation, and heat treatment, our method does not require special equipment (e.g., centrifuge, UV-crosslinker, heating device); therefore, it can be applied in a resource-limited environment with reduced production costs. The immobilization process was streamlined and completed within 30 min. Our method improved the color intensity signal approximately 14 times compared to the method without using SAIoNs and exhibited reproducibility with the long-term storage stability. The proposed method can be used to detect practical targets (e.g., SARS-CoV-2) and facilitates highly sensitive and selective detection of target nucleic acids with multiplexing capability and without any cross-reactivity. This novel immobilization strategy provides a basis for easily and inexpensively developing nucleic acid LFAs combined with various types of nucleic acid amplification.

Caregivers' perceived changes in engaged time with preschool-aged children during COVID-19: Familial correlates and relations to children's learning behavior and emotional distress.

The COVID-19 pandemic and its resulting containment measures have forced many children and their caregivers around the world to spend unprecedented amounts of time at home. Based on a sample of 764 households with preschool-aged children in Wuhan, China, where the pandemic began, this study examined how primary caregivers perceived changes in the amount of time spent engaging with their children (i.e., engaged time) from the start of the pandemic and whether these changes were associated with children's learning behavior and emotional distress. The results showed that primary caregivers generally perceived increases in the amount of engaged time spent on indoor activities with their children but decreases in the amount of engaged time spent playing with their children outdoors. A bigger family size and greater loss of family income during the pandemic were associated with bigger perceived increases in caregivers' engaged time spent on indoor activities, whilst a higher level of parental education was associated with bigger perceived decreases in engaged time spent playing with children outdoors. The family's poorer physical health and higher levels of chaos during the pandemic were related to smaller perceived increases in caregivers' engaged time spent on educational activities. Finally, although bigger perceived increases in caregivers' indoor engaged time (e.g., time spent on educational activities) were associated with higher levels of positive learning behavior and fewer symptoms of anxiety and withdrawal in the children, bigger perceived decreases in outdoor play time were associated with fewer symptoms of anxiety and withdrawal. These findings offer valuable insights into caregivers' allocation of engaged time with their preschool-aged children during the COVID-19 pandemic.

Early chest computed tomography to diagnose COVID-19 from suspected patients: A multicenter retrospective study.

Objective: The purpose of this study was to distinguish the imaging features of COVID-19 from those of other infectious pulmonary diseases and evaluate the diagnostic value of chest CT for suspected COVID-19 patients. Methods: Adult patients suspected of COVID-19 aged >18 years who underwent chest CT scans and reverse-transcription polymerase chain reaction (RT-PCR) tests within 14 days of symptom onset were enrolled. The enrolled patients were confirmed and grouped according to the results of the RT-PCR tests. The basic demographics, single chest CT features, and combined chest CT features were analyzed for the confirmed and nonconfirmed groups. Results: A total of 130 patients were enrolled, with 54 testing positive and 76 testing negative. The typical CT imaging features of the positive group were ground glass opacities (GGOs), the crazy-paving pattern and air bronchogram. The lesions were mostly distributed bilaterally and close to the lower lungs or the pleura. When features were combined, GGOs with bilateral pulmonary distribution and GGOs with pleural distribution were more common among the positive patients, found in 31 (57.4%) and 30 patients (55.6%), respectively. The combinations were almost all statistically significant (P < .05), except for the combination of GGOs with consolidation. Most combinations presented relatively low sensitivity but extremely high specificity. The average specificity of these combinations was approximately 90%. Conclusions: The combinations with GGOs could be useful in the identification and differential diagnosis of COVID-19, alerting clinicians to isolate patients for prompt treatment and repeat RT-PCR tests until the end of incubation.

Novel coronavirus disease (COVID-19) update on epidemiology, pathogenicity, clinical course and treatments.

During the December of 2019, a series of patients with pneumonia caused by novel coronavirus; the severe acute respiratory syndrome (SARS) corona (COV-2), that is, COVID-19. Since the first cluster of cases was reported in China on 31 December 2019 until the 28 April 2020, there were internationally reported 3'000'000 cases, in over 185 countries, and 207'265 deaths. To date, it is still not unanimously clear which effects parameters of virus and host are important for the development of severe disease course. According to the most updated internationally available online cases register, COVID-19 disease has mild symptoms in around 85% of cases, there are 3%-10% of critical cases, and mortality is around 5%-7%. Since currently there is no available vaccine and no well-established specific antiviral therapy, numerous agents are being tested in clinical scenarios. The most common regimens include remdesivir, convalescent plasma. Widely used chloroquine, hydroxychloroquine and azithromycin combinations, as well as lopinavir-ritonavir were shown to have less efficient treatment effects. More severe cases of pneumonia and dyspnoea, or uncontrollable fever are treated as inpatients, and nearly 10% in intensive care units. Oxygen supplementation is indicated to maintain peripheral blood oxygenation over 90%-96%. Advanced support systems include mechanical ventilation and extracorporeal membranous support; however, those without targeted antiviral therapy represent only temporary bridge for scarce potential restitution in patient themselves. The aim of review is to present current state of the art in epidemiology, pathogenesis, clinical course and treatment of COVID-19 patients.

Electrochemical investigations for COVID-19 detection-A comparison with other viral detection methods.

Virus-induced infection such as SARS-CoV-2 is a serious threat to human health and the economic setback of the world. Continued advances in the development of technologies are required before the viruses undergo mutation. The low concentration of viruses in environmental samples makes the detection extremely challenging; simple, accurate and rapid detection methods are in urgent need. Of all the analytical techniques, electrochemical methods have the established capabilities to address the issues. Particularly, the integration of nanotechnology would allow miniature devices to be made available at the point-of-care. This review outlines the capabilities of electrochemical methods in conjunction with nanotechnology for the detection of SARS-CoV-2. Future directions and challenges of the electrochemical biosensors for pathogen detection are covered including wearable and conformal biosensors, detection of plant pathogens, multiplexed detection, and reusable biosensors for on-site monitoring, thereby providing low-cost and disposable biosensors.

Nano-size dependence in the adsorption by the SARS-CoV-2 spike protein over gold colloid.

Gold nano-particles were coated with the spike protein (S protein) of SARS-CoV-2 and exposed to increasingly acidic conditions. Their responses were investigated by monitoring the surface plasmon resonance (SPR) band shift. As the external pH was gradually changed from neutral pH to pH ∼2 the peak of the SPR band showed a significant red-shift, with a sigmoidal feature implying the formation of the gold-protein aggregates. The coating of S protein changed the surface property of the gold enough to extract the coverage fraction of protein over nano particles, Θ, which did not exhibit clear nano-size dependence. The geometrical simulation to explain Θ showed the average axial length to be a = 7. 25 nm and b =8.00 nm when the S-protein was hypothesized as a prolate shape with spiking-out orientation. As the pH value externally hopped between pH∼3 and pH∼10, a behavior of reversible protein folding was observed for particles with diameters >30 nm. It was concluded that S protein adsorption conformation was impacted by the size (diameter, d) of a core nano-gold, where head-to-head dimerized S protein was estimated for d ≤ 80 nm and a parallel in opposite directions formation for d = 100 nm.

Anti-COVID-19 terpenoid from marine sources: A docking, admet and molecular dynamics study.

Traditional medicines contain natural products (NPs) as main ingredient which always give new direction and paths to develop new advanced medicines. In the COVID-19 pandemic, NPs can be used or can help to find new compound against it. The SARS coronavirus-2 main protease (SARS CoV-2 Mpro) enzyme, arbitrate viral replication and transcription, is target here. The study show that, from the electronic features and binding affinity of all the NPs with the enzyme, the compounds with higher hydrophobicity and lower flexibility can be more favorable inhibitor. More than fifty NPs were screened for the target and one terpenoid (T3) from marine sponge Cacospongia mycofijiensis shows excellent SARS CoV-2 Mpro inhibitory activity in comparison with known peptide based inhibitors. The molecular dynamics simulation studies of the terpenoids with the protein indicates that the complex is stable and hydrogen bonds are involved during the complexation. Considering binding affinity, bioavailability, pharmacokinetics and toxicity of the compounds, it is proposed that the NP T3 can act as a potential drug candidate against COVID-19 virus.

Treatment of COVID-19 with pentoxifylline: Could it be a potential adjuvant therapy?

The world is facing a viral pandemic of a new coronavirus called COVID-19. Pentoxifylline is a methyl-xanthine derivative and it inhibits the phosphodiesterase IV (PDE IV). This drug is known for its unique features as an immunomodulatory and anti-inflammatory agent, also it could have antiviral affects. This is a scoping review, in which all related articles on COVID-19 and the probable benefits of Pentoxifylline against COVID-19 pathogenesis, in Medline, Scopus, Web of Sciences, and Google Scholar up to 20 March 2020 with proper keywords including: pentoxifylline, Pentoxil, COVID-19, coronavirus, treatment, anti-inflammatory, immunomodulatory, antifibrosis, oxygenation, circulation, bronchodilator, ARDS, and organ failure. We found many confirmatory data on proper efficacy of pentoxifylline on controlling COVID-19 and its consequences. The antiviral, anti-inflammatory, anti-oxidative, immune-modulatory, bronchodilator and respiratory supportive effects and protective roles in organ failures of PTX, along with its main functions means better circulation-oxygenation properties, low price and safety, make it a promising drug to be considered for COVID-19 treatment, especially as an adjuvant therapy in combination with other drugs.

Predictions for COVID-19 with deep learning models of LSTM, GRU and Bi-LSTM.

COVID-19, responsible of infecting billions of people and economy across the globe, requires detailed study of the trend it follows to develop adequate short-term prediction models for forecasting the number of future cases. In this perspective, it is possible to develop strategic planning in the public health system to avoid deaths as well as managing patients. In this paper, proposed forecast models comprising autoregressive integrated moving average (ARIMA), support vector regression (SVR), long shot term memory (LSTM), bidirectional long short term memory (Bi-LSTM) are assessed for time series prediction of confirmed cases, deaths and recoveries in ten major countries affected due to COVID-19. The performance of models is measured by mean absolute error, root mean square error and r2_score indices. In the majority of cases, Bi-LSTM model outperforms in terms of endorsed indices. Models ranking from good performance to the lowest in entire scenarios is Bi-LSTM, LSTM, GRU, SVR and ARIMA. Bi-LSTM generates lowest MAE and RMSE values of 0.0070 and 0.0077, respectively, for deaths in China. The best r2_score value is 0.9997 for recovered cases in China. On the basis of demonstrated robustness and enhanced prediction accuracy, Bi-LSTM can be exploited for pandemic prediction for better planning and management.

Chloroquine, hydroxychloroquine, and COVID-19: Systematic review and narrative synthesis of efficacy and safety.

The COVID-19 pandemic has required clinicians to urgently identify new treatment options or the re-purposing of existing drugs. Of particular interest are chloroquine (CQ) and hydroxychloroquine (HCQ). The aims of this systematic review are to systematically identify and collate 24 studies describing the use of CQ and HCQ in human clinical trials and to provide a detailed synthesis of evidence of its efficacy and safety. Of clinical trials, 100% showed no significant difference in the probability of viral transmission or clearance in prophylaxis or therapy, respectively, compared to the control group. Among observational studies employing an endpoint specific to efficacy, 58% concurred with the finding of no significant difference in the attainment of outcomes. Three-fifths of clinical trials and half of observational studies examining an indicator unique to drug safety discovered a higher probability of adverse events in those treated patients suspected of, and diagnosed with, COVID-19. Of the total papers focusing on cardiac side-effects, 44% found a greater incidence of QTc prolongation and/or arrhythmias, 44% found no evidence of a significant difference, and 11% mixed results. The strongest available evidence points towards the inefficacy of CQ and HCQ in prophylaxis or in the treatment of hospitalised COVID-19 patients.

Potential mechanisms of Chinese Herbal Medicine that implicated in the treatment of COVID-19 related renal injury.

Clinical studies have shown that renal injury in Corona Virus Disease 2019 (COVID-19) patients has been a real concern, which is associated with high mortality and an inflammation/apoptosis-related causality. Effective target therapy for renal injury has yet been developed. Besides, potential anti-COVID-19 medicines have also been reported to cause adverse side effects to kidney. Chinese Herbal Medicine (CHM), however, has rich experience in treating renal injury and has successfully applied in China in the battle of COVID-19. Nevertheless, the molecular mechanisms of CHM treatment are still unclear. In this study, we searched prescriptions in the treatment of renal injury extensively and the potential mechanisms to treat COVID-19 related renal injury were investigated. The association rules analysis showed that the core herbs includes Huang Qi, Fu Ling, Bai Zhu, Di Huang, Shan Yao. TCM herbs regulate core pathways, such as AGE-RAGE, PI3K-AKT, TNF and apoptosis pathway, etc. The ingredients (quercetin, formononetin, kaempferol, etc.,) from core herbs could modulate targets (PTGS2 (COX2), PTGS1 (COX1), IL6, CASP3, NOS2, and TNF, etc.), and thereby prevent the pharmacological and non-pharmacological renal injury comparable to that from COVID-19 infection. This study provides therapeutic potentials of CHM to combat COVID-19 related renal injury to reduce complications and mortality.

Neurological manifestations of COVID-19 and other coronaviruses: A systematic review.

OBJECTIVE: To describe the main neurological manifestations related to coronavirus infection in humans. METHODOLOGY: A systematic review was conducted regarding clinical studies on cases that had neurological manifestations associated with COVID-19 and other coronaviruses. The search was carried out in the electronic databases PubMed, Scopus, Embase, and LILACS with the following keywords: "coronavirus" or "Sars-CoV-2" or "COVID-19" and "neurologic manifestations" or "neurological symptoms" or "meningitis" or "encephalitis" or "encephalopathy," following the Systematic Reviews and Meta-Analyses (PRISMA) guidelines. RESULTS: Seven studies were included. Neurological alterations after CoV infection may vary from 17.3% to 36.4% and, in the pediatric age range, encephalitis may be as frequent as respiratory disorders, affecting 11 % and 12 % of patients, respectively. The Investigation included 409 patients diagnosed with CoV infection who presented neurological symptoms, with median age range varying from 3 to 62 years. The main neurological alterations were headache (69; 16.8 %), dizziness (57, 13.9 %), altered consciousness (46; 11.2 %), vomiting (26; 6.3 %), epileptic crises (7; 1.7 %), neuralgia (5; 1.2 %), and ataxia (3; 0.7 %). The main presumed diagnoses were acute viral meningitis/encephalitis in 25 (6.1 %) patients, hypoxic encephalopathy in 23 (5.6 %) patients, acute cerebrovascular disease in 6 (1.4 %) patients, 1 (0.2 %) patient with possible acute disseminated encephalomyelitis, 1 (0.2 %) patient with acute necrotizing hemorrhagic encephalopathy, and 2 (1.4 %) patients with CoV related to Guillain-Barré syndrome. CONCLUSION: Coronaviruses have important neurotropic potential and they cause neurological alterations that range from mild to severe. The main neurological manifestations found were headache, dizziness and altered consciousness.

Vanadium: History, chemistry, interactions with α-amino acids and potential therapeutic applications.

In the last 30 years, since the discovery that vanadium is a cofactor found in certain enzymes of tunicates and possibly in mammals, different vanadium-based drugs have been developed targeting to treat different pathologies. So far, the in vitro studies of the insulin mimetic, antitumor and antiparasitic activity of certain compounds of vanadium have resulted in a great boom of its inorganic and bioinorganic chemistry. Chemical speciation studies of vanadium with amino acids under controlled conditions or, even in blood plasma, are essential for the understanding of the biotransformation of e.g. vanadium antidiabetic complexes at the physiological level, providing clues of their mechanism of action. The present article carries out a bibliographical research emphaticizing the chemical speciation of the vanadium with different amino acids and reviewing also some other important aspects such as its chemistry and therapeutical applications of several vanadium complexes.

Contact networks in the emergency department: Effects of time, environment, patient characteristics, and staff role.

Emergency departments play a critical role in the public health system, particularly in times of pandemic. Infectious patients presenting to emergency departments bring a risk of cross-infection to other patients and staff through close proximity interactions or contacts. To understand factors associated with cross-infection risk, we measured close proximity interactions of emergency department staff and patients by radiofrequency identification in a working emergency department. The number of contacts (degree) is not related to patient demographic characteristics. However, the amount of time in close proximity (weighted degree) of patients with ED personnel did differ, with black patients having approximately 15 min more contact with staff than non-white patients. Patients arriving by EMS had fewer contacts with other patients than patients arriving by other means. There are differences in the number of contacts based on staff role and arrival mode. When crowding is low, providers have the most contact time with patients, while administrative staff have the least. However, when crowding is high, this differential is reversed. The effect of arrival mode is modified by the extent of crowding. When crowding is low, patients arriving by EMS had longer contact with administrative staff, compared to patients arriving by other means. However, when crowding is high, patients arriving by EMS had less contact with administrative staff compared to patients arriving by other means. Our findings should help designers of emergency care focus on higher risk situations for transmission of dangerous pathogens in an emergency department. For instance, the effects of arrival and crowding should be considered as targets for engineering or architectural interventions that could artificially increase social distances.

The application of self-assembled nanostructures in peptide-based subunit vaccine development.

Peptide based-vaccines are becoming one of the most widely investigated prophylactic and therapeutic health care interventions against a variety of diseases, including cancer. However, the lack of a safe and highly efficient adjuvant (immune stimulant) is regarded as the biggest obstacle to vaccine development. The incorporation of a peptide antigen in a nanostructure-based delivery system was recently shown to overcome this obstacle. Nanostructures are often formed from antigens conjugated to molecules such as polymers, lipids, and peptide, with the help of self-assembly phenomenon. This review describes the application of self-assembly process for the production of peptide-based vaccine candidates and the ability of these nanostructures to stimulate humoral and cellular immune responses.

Disastrous events and political failures.

Response to the Ebola crisis (ongoing event) has been less than efficient. It has been monitored less than adequately by the international community and has been coordinated poorly in the USA. The event is used as a platform to examine deficiencies in public health infrastructure, the limits of its political and financial support, and how political outcomes can be affected. The need to tease out the political determinants implicit in policy failure and disaster management is argued in this Editorial. Failures mentioned include in the Balkans and in Greece with ongoing austerity. Comments on the real heroes of Ebola on the ground in Africa and the need for a charismatic role for political leaders in public health are also included.

Survey of UK Health Care First Responders' Knowledge of Personal Protective Equipment Requirements.

INTRODUCTION: An adequate level of personal protective equipment (PPE) is necessary when treating patients with highly infectious diseases or those contaminated with hazardous substances. METHODS: Following National Institute for Health Research's Research Centre (London, United Kingdom) approval, the authors of this study conducted a survey of specialist registrars' knowledge of the respiratory and skin protection requirements needed during a resuscitation scenario with Advanced Life Support. Participant responses were compared to UK national recommendations and to a previous survey in 2009. RESULTS: A total of 98 specialist registrars (in Anesthesiology, n=51; in Emergency Medicine (EM), n=21; and in Intensive Care Medicine (ICM) n=26) completed hand-delivered surveys. The best knowledge of PPE requirements (76%) was found for severe acute respiratory syndrome (SARS), with less knowledge about PPE requirements for anthrax, plague, Ebola virus disease (EVD), and smallpox (60%). The results show limited knowledge of PPE requirements (20%-30%) for various chemical warfare agents. Personal protective equipment knowledge regarding treatment of sarin-contaminated casualties was over-rated by 80%, and for patients with EVD, it was over-rated by up to 67% of participants. CONCLUSION: The results of the tested cohort indicate that current knowledge regarding PPE for chemical warfare agents remains very limited.

NMDA Receptor Modulation in COVID-19-Associated Acute Respiratory Syndrome in both In Silico and In Vitro Approach.

The normal function of the N-methyl D-aspartate receptors (NMDAR) in human lungs depends on precisely regulated synaptic glutamate levels. Pathophysiology of the lungs is brought on by the changes in homeostasis of glutamate in the synapsis that leads to abnormal NMDAR activity. Severe acute respiratory syndrome (SARS) primarily results in lung infections, particularly lung muscle stiffening, and NMDA receptor potentiation may increase calcium ion influx and support downstream signaling mechanisms. Hence, NMDAR modulators that depend on glutamate levels could be therapeutically useful medications with fewer unintended side effects. A compound called THP (tetrahydropalmatine) that amplifies Ca2+ influx and potentiates NMDA receptors has been identified in the current study. In asthmatic human airway smooth muscle (HASM) cells, THP regulates the NMDA receptor and helps in asthmatic ASM contraction, and the pharmacological stimulation of ASM depends on both brain and respiratory NMDA receptors. Glutamate potency is altered by this substance without any voltage-dependent side effects. Additionally, a GGPP (geranylgeranyl pyrophosphate)-dependent mechanism of THP reduced the production of pro-inflammatory cytokines in ASM. THP is distinctive in terms of its chemical makeup, functioning, and agonist concentration-dependent and allosteric modulatory activity. To treat COVID-19-related SARS, THP, or any future-related compounds will make good drug-like molecule candidates.

Chinese pregnant women's knowledge, attitude, and practice of self-protection against coronavirus disease 2019 during the post-pandemic period: A structural equation modeling-based survey.

This study aimed to investigate the Chinese pregnant women's levels of knowledge, attitude, and practice (KAP) of self-protection against coronavirus disease 2019 (COVID-19) during the post-pandemic period, to aid the development of targeted health education. An online questionnaire was conducted for 2156 Chinese pregnant women from October 1, 2021, to December 31, 2021, to collect socio-demographic and KAP information. Structural equation modeling (SEM) was used to determine self-protection-related factors. The mean age of the participants was 30 ± 4.1 years. SEM indicated that pregnant women's level of knowledge can directly and indirectly affect the practice of self-protection (r = 0.23) through their belief, with a correlation coefficient of 0.56 and 0.46 between knowledge and belief and belief and practice, respectively. The "basic protection" and "hospital visits after infection" exerted the greatest impact on knowledge formation, with correlation coefficients of 0.85 and 0.89, respectively. Attitude had a direct effect on practice with a correlation coefficient of 0.46. "Awareness of prevention and control" and "family and social support" had the greatest impact on belief formation, with correlation coefficients of 0.77 and 0.73, respectively. Pregnant Chinese women were generally familiar with COVID-19 knowledge, and their levels of knowledge and beliefs particularly affect the practice of self-protection. Health education aimed at improving pregnant women's knowledge and belief toward self-protection against COVID-19 may be an effective way to guide them toward positive practices and promote their health and that of their babies.

Inhibition of SARS-CoV-2 nucleocapsid protein-RNA interaction by guanosine oligomeric RNA.

The interaction of the ß-coronavirus severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) nucleocapsid (N) protein with genomic RNA is initiated by specific RNA regions and subsequently induces the formation of a continuous polymer with characteristic structural units for viral formation. We hypothesized that oligomeric RNAs, whose sequences are absent in the 29.9-kb genome sequence of SARS-CoV-2, might affect RNA-N protein interactions. We identified two such hexameric RNAs, In-1 (CCGGCG) and G6 (GGGGGG), and investigated their effects on the small filamentous/droplet-like structures (< a few µm) of N protein-genomic RNA formed by liquid-liquid phase separation. The small N protein structures were sequence-specifically enhanced by In-1, whereas G6 caused them to coalesce into large droplets. Moreover, we found that a guanosine 12-mer (G12, GGGGGGGGGGGG) expelled preexisting genomic RNA from the small N protein structures. The presence of G12 with the genomic RNA suppressed the formation of the small N protein structures, and alternatively apparently altered phase separation to induce the formation of large droplets with unclear phase boundaries. We showed that the N-terminal RNA-binding domain is required for the stability of the small N protein structures. Our results suggest that G12 may be a strong inhibitor of the RNA-N protein interaction.