Association between population density and infection rate suggests the importance of social distancing and travel restriction in reducing the COVID-19 pandemic.

Currently, 2019-nCoV has spread to most countries of the world. Understanding the environmental factors that affect the spread of the disease COVID-19 infection is critical to stop the spread of the disease. The purpose of this study is to investigate whether population density is associated with the infection rate of the COVID-19. We collected data from official webpages of cities in China and in the USA. The data were organized on Excel spreadsheets for statistical analyses. We calculated the morbidity and population density of cities and regions in these two countries. We then examined the relationship between morbidity and other factors. Our analysis indicated that the population density in cities in Hubei province where the COVID-19 was severe was associated with a higher percentage of morbidity, with an r value of 0.62. Similarly, in the USA, the density of 51 states and territories is also associated with morbidity from COVID-19 with an r value of 0.55. In contrast, as a control group, there is no association between the morbidity and population density in 33 other regions of China, where the COVID-19 epidemic is well under control. Interestingly, our study also indicated that these associations were not influenced by the first case of COVID-19. The rate of morbidity and the number of days from the first case in the USA have no association, with an r value of - 0.1288. Population density is positively associated with the percentage of patients with COVID-19 infection in the population. Our data support the importance of such as social distancing and travel restriction in the prevention of COVID-19 spread.

The Network of Interactions between the Porcine Epidemic Diarrhea Virus Nucleocapsid and Host Cellular Proteins.

Host-virus protein interactions are critical for intracellular viral propagation. Understanding the interactions between cellular and viral proteins may help us develop new antiviral strategies. Porcine epidemic diarrhea virus (PEDV) is a highly contagious coronavirus that causes severe damage to the global swine industry. Here, we employed co-immunoprecipitation and liquid chromatography-mass spectrometry to characterize 426 unique PEDV nucleocapsid (N) protein-binding proteins in infected Vero cells. A protein-protein interaction network (PPI) was created, and gene ontology (GO) annotation and Kyoto Encyclopedia of Genes and Genomes (KEGG) database analyses revealed that the PEDV N-bound proteins belong to different cellular pathways, such as nucleic acid binding, ribonucleoprotein complex binding, RNA methyltransferase, and polymerase activities. Interactions of the PEDV N protein with 11 putative proteins: tripartite motif containing 21, DEAD-box RNA helicase 24, G3BP stress granule assembly factor 1, heat shock protein family A member 8, heat shock protein 90 alpha family class B member 1, YTH domain containing 1, nucleolin, Y-box binding protein 1, vimentin, heterogeneous nuclear ribonucleoprotein A2/B1, and karyopherin subunit alpha 1, were further confirmed by in vitro co-immunoprecipitation assay. In summary, studying an interaction network can facilitate the identification of antiviral therapeutic strategies and novel targets for PEDV infection.

Bead-Based Multiplexed Droplet Digital Polymerase Chain Reaction in a Single Tube Using Universal Sequences: An Ultrasensitive, Cross-Reaction-Free, and High-Throughput Strategy.

The multiplexed digital polymerase chain reaction (PCR) is widely used in molecular diagnosis owing to its high sensitivity and throughput for multiple target detection compared with the single-plexed digital PCR; however, current multiplexed digital PCR technologies lack efficient coding strategies that do not compromise the sensitivity and signal-to-noise (S/N) ratio. Hence, we propose a fluorescent-encoded bead-based multiplexed droplet digital PCR method for ultra-high coding capacity, along with the creative design of universal sequences (primer and fluorescent TaqMan probe) for ultra-sensitivity and high S/N ratios. First, pre-amplification is used to introduce universal primers and universal fluorescent TaqMan probes to reduce primer interference and background noise, as well as to enrich regions of interest in targeted analytes. Second, fluorescent-encoded beads (FEBs), coupled with the corresponding target sequence-specific capture probes through streptavidin-biotin conjugation, are used to partition amplicons via hybridization according to the Poisson distribution. Finally, FEBs mixed with digital PCR mixes are isolated into droplets generated via Sapphire chips (Naica Crystal Digital PCR system) to complete the digital PCR and result analysis. For proof of concept, we demonstrate that this method achieves high S/N ratios in a 5-plexed assay for influenza viruses and SARS-CoV-2 at concentrations below 10 copies and even close to a single molecule per reaction without cross-reaction, further verifying the possibility of clinical actual sample detection with 100% accuracy, which paves the way for the realization of digital PCR with ultrahigh coding capacity and ultra-sensitivity.

Reconstruction of the Evolutionary Origin, Phylodynamics, and Phylogeography of the Porcine Circovirus Type 3.

Porcine circovirus type 3 (PCV3) is a newly identified virus associated with porcine dermatitis and nephropathy syndrome (PDNS) and multisystemic inflammatory responses in pigs. Recent studies suggests that PCV3 originated from bat circoviruses; however, the origin time, mode of spread, and geographic distribution of PCV3 remain unclear. In this study, the evolutionary origin, phylodynamics, and phylogeography of PCV3 were reconstructed based on the available complete genome sequences. PCV3 showed a closer relationship with bird circovirus than with bat circovirus, but their common ancestor was bat circovirus, indicating that birds may be intermediate hosts for the spread of circoviruses in pigs. Using the BEAST and phylogenetic analyses, three different clades of PCV3 (PCV3a, PCV3b, and PCV3c) were identified, with PCV3a being the most prevalent PCV3 clade. Further studies indicated that the earliest origin of PCV3 can be traced back to 1907.53-1923.44, with a substitution rate of 3.104 × 10-4 to 6.8524 × 10-4 substitution/site/year. A phylogeographic analysis highlighted Malaysia as the earliest location of the original PCV3, which migrated to Asia, America, and Europe. Overall, this study provides novel insights into the evolutionary origin, spread mode, and geographic distribution of PCV3, which will facilitate the prevention and control of PCV3 epidemics in the future.

Effectiveness of a Game-Based Phone Application in Educating Health Care Workers on the Proper Use of Personal Protective Equipment.

Objective This study explored the feasibility and effects of a game-based phone application for training health care workers to use personal protective equipment. Method A single-blind randomized controlled trial was conducted. All participants in the experimental group (n = 123) and the control group (n = 125) received 75 minutes of training and were provided with a video and a paper copy of the procedures. Participants in the experimental group used an additional game-based phone application to simulate the procedures. Results Participants in the experimental group practiced a median of 15 times (range, 14-19 times). The learning curve indicated that they needed at least 12 repetitions to master the skill. Score improvements (Z = -2.257, p = .024) in the experimental group were significantly superior to those in the control group, as were the incidences of procedural errors of hand hygiene (χ2 = 4.085, p = .043) and protective clothing (χ2 = 5.394, p = .02). Conclusion The game-based phone application simulation guided participants to practice enough times to master the skill, enhance their skill performance, and reduce the incidence of procedural errors. [J Contin Educ Nurs. 2022;53(5):212-220.].

Potential Use of Serum Proteomics for Monitoring COVID-19 Progression to Complement RT-PCR Detection.

RT-PCR is the primary method to diagnose COVID-19 and is also used to monitor the disease course. This approach, however, suffers from false negatives due to RNA instability and poses a high risk to medical practitioners. Here, we investigated the potential of using serum proteomics to predict viral nucleic acid positivity during COVID-19. We analyzed the proteome of 275 inactivated serum samples from 54 out of 144 COVID-19 patients and shortlisted 42 regulated proteins in the severe group and 12 in the non-severe group. Using these regulated proteins and several key clinical indexes, including days after symptoms onset, platelet counts, and magnesium, we developed two machine learning models to predict nucleic acid positivity, with an AUC of 0.94 in severe cases and 0.89 in non-severe cases, respectively. Our data suggest the potential of using a serum protein-based machine learning model to monitor COVID-19 progression, thus complementing swab RT-PCR tests. More efforts are required to promote this approach into clinical practice since mass spectrometry-based protein measurement is not currently widely accessible in clinic.

Metformin in Patients With COVID-19: A Systematic Review and Meta-Analysis.

Importance/Background: The coronavirus disease (COVID-19) pandemic is a critical public health issue. Evidence has shown that metformin favorably influences COVID-19 outcomes. This study aimed to assess the benefits and risks of metformin in COVID-19 patients. Methods: We searched the PubMed, Embase, Cochrane Library, and Chinese Biomedical Literature Database from inception to February 18, 2021. Observational studies assessing the association between metformin use and the outcomes of COVID-19 patients were included. The primary outcome was mortality, and the secondary outcomes included intubation, deterioration, and hospitalization. Random-effects weighted models were used to pool the specific effect sizes. Subgroup analyses were conducted by stratifying the meta-analysis by region, diabetic status, the adoption of multivariate model, age, risk of bias, and timing for adding metformin. Results: We identified 28 studies with 2,910,462 participants. Meta-analysis of 19 studies showed that metformin is associated with 34% lower COVID-19 mortality [odds ratio (OR), 0.66; 95% confidence interval (CI), 0.56-0.78; I 2 = 67.9%] and 27% lower hospitalization rate (pooled OR, 0.73; 95% CI, 0.53-1.00; I 2 = 16.8%). However, we did not identify any subgroup effects. The meta-analysis did not identify statistically significant association between metformin and intubation and deterioration of COVID-19 (OR, 0.94; 95% CI, 0.77-1.16; I 2 = 0.0% for intubation and OR, 2.04; 95% CI, 0.65-6.34; I 2 = 79.4% for deterioration of COVID-19), respectively. Conclusions: Metformin use among COVID-19 patients was associated with a reduced risk of mortality and hospitalization. Our findings suggest a relative benefit for metformin use in nursing home and hospitalized COVID-19 patients. However, randomized controlled trials are warranted to confirm the association between metformin use and COVID-19 outcomes. Study Registration: The study was registered on the PROSPERO on Feb 23, 2021 (CRD42021238722).

Management of early-stage breast cancer patients during the coronavirus disease 2019 (COVID-19) pandemic: The experience in China from a surgical standpoint.

Breast cancer is the most common malignant tumor in women globally. Currently, due to limited data, there are no international guidelines for addressing the management of a large group of patients during infectious disease pandemics. Coronavirus disease 2019 (COVID-19), declared as a pandemic by the World Health Organization (WHO), has rapidly spread globally. The COVID-19 pandemic changed our daily routines and forced us to rethink the management of breast cancer patients. Clinicians need to take into account multiple factors such as the timing and delivery of cancer care, epidemic prevention and control, and the allocation of medical resources. Determining ways to reasonably adjust the treatment strategy is a real challenge. In this review, we aim to discuss particular challenges associated with managing breast cancer patients during the COVID-19 pandemic, share experience from Chinese oncologists and surgeons and propose some practical approaches to the management of early-stage breast cancer patients from a surgical standpoint.

Complications and Pathophysiology of COVID-19 in the Nervous System.

The coronavirus disease (COVID-19) pandemic, caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has become a global public health threat. Majority of the patients with COVID-19 have fever, cough, and fatigue. Critically ill patients can develop dyspnea and acute respiratory distress syndrome. In addition to respiratory symptoms, neurological damage also occurs in some patients. However, the mechanisms by which SARS-CoV-2 invades the nervous system have not been elucidated yet. In order to provide some reference for designing optimal therapeutic strategies, we have discussed the complications and potential mechanisms of COVID-19 in the nervous system in this review.