Holistic sleep improvement strategies for frontline nurses served during a public health emergency (COVID-19) in Wuhan, China: A quasi-experimental study.

AIM: To examine effects of holistic sleep improvement strategies on frontline nurses who served in Wuhan, China, during a public health emergency (COVID-19). DESIGN: A pre-post-test design with single group was conducted with a convenience sample applied the Transparent Reporting of Evaluations with Non-randomized Designs statement. METHODS: Fifty-two nurses were recruited from a COVID-19 designated hospital, receiving holistic sleep improvement intervention, which concentrated on scientific human resource management, comfortable sleep environment establishment, self-relaxation and self-adjustment training and humanistic care. Data was collected at baseline and 4-week follow-up post intervention using self-reported questionnaires. RESULTS: The total score of Pittsburgh Sleep Quality Index scale was 8.69 ± 4.346 at baseline. After 4 weeks of follow-up, the score statistically significantly decreased to 7.48 ± 3.691. Subjective sleep quality (p = .016), sleep efficiency (p = .015), sleep disturbances (p = .007) were statistically significantly improved after the intervention, while there were no statistically significant differences in sleep latency (p = .205), sleep duration (p = .375), sleep medication (p = .723) or daytime dysfunction (p = .747).

DEAD-box RNA helicase 21 negatively regulates cytosolic RNA-mediated innate immune signaling.

DEAD-box RNA helicase 21 (DDX21), also known as RHII/Gu, is an ATP-dependent RNA helicase. In addition to playing a vital role in regulating cellular RNA splicing, transcription, and translation, accumulated evidence has suggested that DDX21 is also involved in the regulation of innate immunity. However, whether DDX21 induces or antagonizes type I interferon (IFN-I) production has not been clear and most studies have been performed through ectopic overexpression or RNA interference-mediated knockdown. In this study, we generated DDX21 knockout cell lines and found that knockout of DDX21 enhanced Sendai virus (SeV)-induced IFN-ß production and IFN-stimulated gene (ISG) expression, suggesting that DDX21 is a negative regulator of IFN-ß. Mechanistically, DDX21 competes with retinoic acid-inducible gene I (RIG-I) for binding to double-stranded RNA (dsRNA), thereby attenuating RIG-I-mediated IFN-ß production. We also identified that the 217-784 amino acid region of DDX21 is essential for binding dsRNA and associated with its ability to antagonize IFN production. Taken together, our results clearly demonstrated that DDX21 negatively regulates IFN-ß production and functions to maintain immune homeostasis.

Norovirus 3C-Like protease antagonizes interferon-ß production by cleaving NEMO.

An epidemic owing to Norovirus (NoV) has recently been occurring worldwide. Severe cases of NoV can lead to patient death, resulting in significant public health problems. In the early stages of infection, antagonizing the production of host interferon (IFN) is an important strategy for viruses to establish infection. However, the relationship between NoV and interferon and its mechanism remains unclear. In this study, the 3C-like protease encoded by NoV was found to effectively suppress Sendai virus (SEV)-mediated IFN-ß production by cleaving the NF-κB essential modulator (NEMO). Glutamine 205 is the site of NoV3CLpro-mediated cleavage of NEMO and this cleavage suppresses the ability of NEMO to activate downstream IFN production. These findings demonstrate that NoV3CLpro-induced cleavage limits NEMO to the activation of type I IFN signaling. In summary, our findings indicate that NoV3CLpro is a new interferon antagonist, and enhances our understanding of the escape of innate immunity mediated by NoV3CLpro.

Cholesterol 25-hydroxylase suppresses porcine deltacoronavirus infection by inhibiting viral entry.

Cholesterol 25-hydroxylase (CH25 H) is a key enzyme regulating cholesterol metabolism and also acts as a broad antiviral host restriction factor. Porcine deltacoronavirus (PDCoV) is an emerging swine enteropathogenic coronavirus that can cause vomiting, diarrhea, dehydration and even death in newborn piglets. In this study, we found that PDCoV infection significantly upregulated the expression of CH25H in IPI-FX cells, a cell line of porcine ileum epithelium. Overexpression of CH25H inhibited PDCoV replication, whereas CH25H silencing using RNA interference promoted PDCoV infection. Treatment with 25-hydroxycholesterol (25HC), the catalysate of cholesterol via CH25H, inhibited PDCoV proliferation by impairing viral invasion of IPI-FX cells. Furthermore, a mutant CH25H (CH25H-M) lacking hydroxylase activity also inhibited PDCoV infection to a lesser extent. Taken together, our data suggest that CH25H acts as a host restriction factor to inhibit the proliferation of PDCoV but this inhibitory effect is not completely dependent on its enzymatic activity.

GSH-ZnS Nanoparticles Exhibit High-Efficiency and Broad-Spectrum Antiviral Activities via Multistep Inhibition Mechanisms.

Despite the good biocompatibility and antibacterial activity of zinc sulfide nanoparticles (ZnS NPs), whether they possess antiviral activity is still unclear. Here, GSH-modified ZnS NPs (GSH-ZnS NPs) were synthesized and their significant antiviral activity was demonstrated using the Arteriviridae family RNA virus, porcine reproductive and respiratory syndrome virus (PRRSV), as a model. Mechanistically, GSH-ZnS NPs were shown to reduce PRRSV-induced ROS production to prevent PRRSV multiplication, with no activating effect on the interferon (IFN) signal pathway, the first defense line against virus infection. Furthermore, isobaric tags for relative and absolute quantification (iTRAQ)-based quantitative proteomic analysis of GSH-ZnS NP-treated cells revealed the involvement of numerous crucial proteins in virus proliferation, with vitronectin (VTN) being confirmed as an efficient PRRSV antagonist here. Furthermore, GSH-ZnS NPs were found to have potent antiviral effects on the Herpesviridae family DNA virus, pseudorabies virus (PRV), the Coronaviridae family positive-sense RNA virus, porcine epidemic diarrhea virus (PEDV), and the Rhabdoviridae family negative-stranded RNA virus, vesicular stomatitis virus (VSV), indicating their broad-spectrum antiviral activity against viruses from different families with various genome types. Overall, GSH-ZnS NP is a prospective candidate for the development of antiviral nanomaterials and may serve as a model for investigation of potential host restriction factors in combination with proteomics.

High antiviral activity of mercaptoethane sulfonate functionalized Te/BSA nanostars against arterivirus and coronavirus.

Heparan sulfate (HS) is a kind of cellular adhesion receptor that mediates the attachment and internalization of virus infection. Herein, to mimic the cell surface receptor, mercaptoethane sulfonate (MES), an analogue of HS, was used as the surface modifier to synthesize bovine serum albumin (BSA)-coated tellurium nanoparticles (Te/BSA NPs) with a unique triangular star shape (Te/BSA nanostars). Using porcine reproductive and respiratory syndrome virus (PRRSV), which utilizes HS as a cellular receptor, as a model of arterivirus, we found that Te/BSA nanostars suppressed virus infection mainly by inhibiting the virus internalization process. Interestingly, Te/BSA nanostars exhibited much higher antiviral activity than the spherical Te/BSA NPs (Te/BSA nanospheres), the Te/BSA NPs were synthesized with GSH as a substitute of MES, suggesting that both MES modification and the novel shapes of Te/BSA NPs enhance their antiviral activity. Finally, the antiviral effect of Te/BSA nanostars on porcine epidemic diarrhea virus (PEDV), a model of coronavirus, was also demonstrated, indicating the potential broad-spectrum antiviral property of Te/BSA nanostars.

CD163 and pAPN double-knockout pigs are resistant to PRRSV and TGEV and exhibit decreased susceptibility to PDCoV while maintaining normal production performance.

Porcine reproductive and respiratory syndrome virus (PRRSV) and transmissible gastroenteritis virus (TGEV) are two highly infectious and lethal viruses causing major economic losses to pig production. Here, we report generation of double-gene-knockout (DKO) pigs harboring edited knockout alleles for known receptor proteins CD163 and pAPN and show that DKO pigs are completely resistant to genotype 2 PRRSV and TGEV. We found no differences in meat-production or reproductive-performance traits between wild-type and DKO pigs, but detected increased iron in DKO muscle. Additional infection challenge experiments showed that DKO pigs exhibited decreased susceptibility to porcine deltacoronavirus (PDCoV), thus offering unprecedented in vivo evidence of pAPN as one of PDCoV receptors. Beyond showing that multiple gene edits can be combined in a livestock animal to achieve simultaneous resistance to two major viruses, our study introduces a valuable model for investigating infection mechanisms of porcine pathogenic viruses that exploit pAPN or CD163 for entry.

Pig epidemics are the biggest threat to the pork industry. In 2019 alone, hundreds of billions of dollars worldwide were lost due to various pig diseases, many of them caused by viruses. The porcine reproductive and respiratory virus (PRRS virus for short), for instance, leads to reproductive disorders such as stillbirths and premature labor. Two coronaviruses ­ the transmissible gastroenteritis virus (or TGEV) and the porcine delta coronavirus ­ cause deadly diarrhea and could potentially cross over into humans. Unfortunately, there are still no safe and effective methods to prevent or control these pig illnesses, but growing disease-resistant pigs could reduce both financial and animal losses. Traditionally, breeding pigs to have a particular trait is a slow process that can take many years. But with gene editing technology, it is possible to change or remove specific genes in a single generation of animals. When viruses infect a host, they use certain proteins on the surface of the host's cells to find their inside: the PRRS virus relies a protein called CD163, and TGEV uses pAPN. Xu, Zhou, Mu et al. used gene editing technology to delete the genes that encode the CD163 and pAPN proteins in pigs. When the animals were infected with PRRS virus or TGEV, the non-edited pigs got sick but the gene-edited animals remained healthy. Unexpectedly, pigs without CD163 and pAPN also coped better with porcine delta coronavirus infections, suggesting that CD163 and pAPN may also help this coronavirus infect cells. Finally, the gene-edited pigs reproduced and produced meat as well as the control pigs. These experiments show that gene editing can be a powerful technology for producing animals with desirable traits. The gene-edited pigs also provide new knowledge about how porcine viruses infect pigs, and may offer a starting point to breed disease-resistant animals on a larger scale.

Porcine Deltacoronavirus nsp5 Cleaves DCP1A To Decrease Its Antiviral Activity.

Porcine deltacoronavirus (PDCoV) is an emerging swine enteropathogenic coronavirus. The nonstructural protein nsp5, also called 3C-like protease, is responsible for processing viral polyprotein precursors in coronavirus (CoV) replication. Previous studies have shown that PDCoV nsp5 cleaves the NF-κB essential modulator and the signal transducer and activator of transcription 2 to disrupt interferon (IFN) production and signaling, respectively. Whether PDCoV nsp5 also cleaves IFN-stimulated genes (ISGs), IFN-induced antiviral effector molecules, remains unclear. In this study, we screened 14 classical ISGs and found that PDCoV nsp5 cleaved the porcine mRNA-decapping enzyme 1a (pDCP1A) through its protease activity. Similar cleavage of endogenous pDCP1A was also observed in PDCoV-infected cells. PDCoV nsp5 cleaved pDCP1A at glutamine 343 (Q343), and the cleaved pDCP1A fragments, pDCP1A1-343 and pDCP1A344-580, were unable to inhibit PDCoV infection. Mutant pDCP1A-Q343A, which resists nsp5-mediated cleavage, exhibited a stronger ability to inhibit PDCoV infection than wild-type pDCP1A. Interestingly, the Q343 cleavage site is highly conserved in DCP1A homologs from other mammalian species. Further analyses demonstrated that nsp5 encoded by seven tested CoVs that can infect human or pig also cleaved pDCP1A and human DCP1A, suggesting that DCP1A may be the common target for cleavage by nsp5 of mammalian CoVs.IMPORTANCE Interferon (IFN)-stimulated gene (ISG) induction through IFN signaling is important to create an antiviral state and usually directly inhibits virus infection. The present study first demonstrated that PDCoV nsp5 can cleave mRNA-decapping enzyme 1a (DCP1A) to attenuate its antiviral activity. Furthermore, cleaving DCP1A is a common characteristic of nsp5 proteins from different coronaviruses (CoVs), which represents a common immune evasion mechanism of CoVs. Previous evidence showed that CoV nsp5 cleaves the NF-κB essential modulator and signal transducer and activator of transcription 2. Taken together, CoV nsp5 is a potent IFN antagonist because it can simultaneously target different aspects of the host IFN system, including IFN production and signaling and effector molecules.