SARS-CoV-2 NSP13 interacts with host IRF3, blocking antiviral immune responses.

Coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), poses an unprecedented threat to human health since late 2019. Notably, the progression of the disease is associated with impaired antiviral interferon (IFN) responses. Although multiple viral proteins were identified as potential IFN antagonists, the underlying molecular mechanisms remain to be fully elucidated. In this study, we firstly demonstrate that SARS-CoV-2 NSP13 protein robustly antagonizes IFN response induced by the constitutively active form of transcription factor IRF3 (IRF3/5D). This induction of IFN response by IRF3/5D is independent of the upstream kinase, TBK1, a previously reported NSP13 target, thus indicating that NSP13 can act at the level of IRF3 to antagonize IFN production. Consistently, NSP13 exhibits a specific, TBK1-independent interaction with IRF3, which, moreover, is much stronger than that of NSP13 with TBK1. Furthermore, the NSP13-IRF3 interaction was shown to occur between the NSP13 1B domain and IRF3 IRF association domain (IAD). In agreement with the strong targeting of IRF3 by NSP13, we then found that NSP13 blocks IRF3-directed signal transduction and antiviral gene expression, counteracting IRF3-driven anti-SARS-CoV-2 activity. These data suggest that IRF3 is likely to be a major target of NSP13 in antagonizing antiviral IFN responses and provide new insights into the SARS-CoV-2-host interactions that lead to viral immune evasion.

Effectiveness of Meningococcal Vaccines at Reducing Invasive Meningococcal Disease and Pharyngeal Neisseria meningitidis Carriage: A Systematic Review and Meta-analysis.

BACKGROUND: Invasive meningococcal disease (IMD), caused by Neisseria meningitidis, leads to significant morbidity and mortality worldwide. This review aimed to establish the effectiveness of meningococcal vaccines at preventing IMD and N. meningitidis pharyngeal carriage. METHODS: A search within PubMed, Embase, Scopus, and unpublished studies up to 1 February 2020 was conducted. RESULTS: After removal of duplicates, 8565 studies were screened and 27 studies included. Protection was provided by meningococcal C vaccines for group C IMD (odds ratio [OR], 0.13 [95% confidence interval {CI}, .07-.23]), outer membrane vesicle (OMV) vaccines against group B IMD (OR, 0.35 [95% CI, .25-.48]), and meningococcal A, C, W, Y (MenACWY) vaccines against group ACWY IMD (OR, 0.31 [95% CI, .20-.49]). A single time series analysis found a reduction following an infant 4CMenB program (incidence rate ratio, 0.25 [95% CI, .19-.36]). Multivalent MenACWY vaccines did not reduce carriage (relative risk [RR], 0.88 [95% CI, .66-1.18]), unlike monovalent C vaccines (RR, 0.50 [95% CI, .26-.97]). 4CMenB vaccine had no effect on group B carriage (RR, 1.12 [95% CI, .90-1.40]). There was also no reduction in group B carriage following MenB-FHbp vaccination (RR, 0.98 [95% CI, .53-1.79]). CONCLUSIONS: Meningococcal conjugate C, ACWY, and OMV vaccines are effective at reducing IMD. A small number of studies demonstrate that monovalent C conjugate vaccines reduce pharyngeal N. meningitidis carriage. There is no evidence of carriage reduction for multivalent MenACWY, OMV, or recombinant MenB vaccines, which has implications for immunization strategies. CLINICAL TRIALS REGISTRATION: CRD42018082085 (PROSPERO).

Inlet Particle-Sorting Cyclone for the Enhancement of PM2.5 Separation.

Many cities are suffering from severe air pollution from fine particulate matter. Cyclone is an effective separator for particulate pollutant but has low efficiency for those with an aerodynamic diameter of 2.5 µm or less (PM2.5). In this research, four novel inlet particle-sorting cyclones were first developed to enhance the separation of PM2.5. The energy consumption, overall separation efficiency, particle grade efficiency,outlet particle concentration and size distribution were compared with common cyclone (CM-C). It was found that the vertical reverse rotation cyclone (VRR-C), which made the smaller particles enter cyclone from radially outer side and axially lower side at the rectangular inlet, had the best separation performance, especially for PM2.5 separation. The mean diameter of inlet particles was 15.7 µm and the particle concentration was 2000 mg/m3, the overall separation efficiency of the VRR-C reached 98.3%, which was 6.4% higher than that of CM-C. PM2.5 grade efficiency of the VRR-C exceeded 80%, which was 15∼20% higher than that of CM-C. The PM2.5 content at the VRR-C outlet was 30.8 mg/m3, while that of CM-C was still 118.4 mg/m3. The novel inlet particle-sorting cyclone is an effective separation enhancement for PM2.5 source control in the process of industrial production and environment protection.

Modified sphenoidotomy for isolated sphenoid sinus disease: A series of 117 cases.

BACKGROUND: The atresia rate of sphenoid ostium after endoscopic sphenoidotomy for isolated sphenoid disease is 9.4%-10.2%. AIMS: To reduce sphenoid sinus ostium atresia rate after sphenoidotomy surgery. MATERIALS AND METHODS: The data of patients with isolated sphenoid sinus disease at our hospital between 2015 and 2022 were retrospectively analyzed. The age, gender, disease course, pathology, postoperative follow-up time, anatomy data of sphenoid sinus and postoperative sinus ostium atresia rate were compared between the two groups of patients with traditional sphenoidotomy and modified sphenoidotomy. RESULTS: A total of 117 patients with isolated sphenoid sinus disease underwent endoscopic sphenoidotomy. There were 76 cases in the traditional sphenoidotomy group, fungus ball in 59.2% of patients, the postoperative sinus ostium atresia rate was 14.5%. There were 41 cases in the modified sphenoidotomy group, fungus ball in 53.6% of patients, and 0 case of sinus ostium atresia. Statistical analysis showed significant differences in postoperative sinus ostium atresia rate. There was no significant difference in age, pathology, postoperative follow-up time, anatomy data of sphenoid, and other data. CONCLUSIONS AND SIGNIFICANCE: The modified endoscopic sphenoidotomy may reduce the rate of postoperative sinus ostium atresia.

A novel hydrocyclone for use in underground DNAPL phase separation.

Halogenated organic solvents are the most commonly detected pollutants in groundwater and are particularly toxic and harmful. How to separate these dense nonaqueous phase liquid (DNAPL) pollutants efficiently from groundwater has become an important research question. Here, a novel hydrocyclone with annular overflow structure was designed, which eliminated the short-circuit flow of the traditional hydrocyclone and solved the problem of overflow entrainment caused by the enrichment of droplets near the locus of zero vertical velocities (LZVV) into turbulence. The flow field characteristics of this novel hydrocyclone were studied using Computational Fluid Dynamics (CFD) simulation and compared with the traditional hydrocyclone. It was found that the annular gap structure of the novel hydrocyclone increased the tangential velocity of the outer vortex. Moreover, the radius of the LZVV was expanded outward by 0.17 mm, which reduced the possibility of droplets with small particle sizes in the second phase escaping from the overflow pipe. The collective effect was to eliminate the short-circuit flow. This novel hydrocyclone was able to separate DNAPL pollutants with low consumption and high efficiency, across a range of inlet velocity from 4 to 6 m/s. The maximum separation efficiency was 99.91 %. In addition, with trichloroethylene (TCE) as the target pollutant, the maximum volume fraction of the dispersed phase in the hydrocyclone was located on the side wall of the hydrocyclone. Taken together, we believe that this work will provide a low-cost, efficient separation method for the separation of groundwater- contaminated liquid mixtures. Furthermore, it has broad application prospects in the field of heterotopic remediation of groundwater.

Removal of coke powders in coking wastewater using a hydrocyclone optimized by n-value.

Coke powders in the coking wastewater generated by petroleum refining industry needs to be removed to achieve water reuse for lack of water resources. This study developed a decoking hydrocyclone in the closed coking wastewater circulation treatment system to remove coke powders, which was highly efficient and environmentally friendly. Computational Fluid Dynamics (CFD) method was carried out to study the tangential velocity distribution index n-value to guide design of decoking hydrocyclone and experiment was conducted to verify the coke powders removal effect. It was found that the increase of n-value is conducive to the improvement of coke powders separation efficiency. A decoking hydrocyclone with a cone angle of 15° and an inlet size of 4 × 6 mm is the optimum hydrocyclone and the recovery efficiency of coke powders is stable at more than 90%. It is the first time for hydrocyclone successfully applied to the removal of coke powders in coking wastewater in the decoking process of petroleum refining industry, in which the separation efficiency of coke powders is considerably improved.

[Clinical analysis of 10 cases of olfactory neuroblastoma].

OBJECTIVE: To review the diagnosis, treatment and prognosis of olfactory neuroblastoma. METHODS: Clinical data were retrospectively reviewed in 10 cases of olfactory neuroblastoma admitted from 1998 to 2002, including data of transmission electron microscopic (TEM) observation in 4 cases. According to Kadish's classification, 2 cases were in stage A, 4 in stage B and 4 in stage C. Three patients were treated with surgery alone, 7 with combined surgery and radiation. RESULT: Among 10 cases, the overall 5-year survival rate was 60 %(6/10); 3 patients died from local recurrence, 1 lost follow-up. TEM demonstrated granules in the cytoplasm of 3 patients. CONCLUSION: The combined surgery and radiation can achieve excellent local control. Transmission electron microscope is important for its diagnosis.

Preparation and properties of OSA-modified taro starches and their application for stabilizing Pickering emulsions.

In this study, the octenylsuccinylated taro starches (OSTS) with different degree of substitution (DS, from 0.009 to 0.032) were prepared and their structural properties such as granule size, wettability and morphology were studied. The purpose of this work was to elucidate the OSTS with different DS using as particle stabilizers for Pickering emulsions, and the effect of DS on the stability, droplet size, microstructure and rheological properties of OSTS-stabilized emulsions were investigated. Octenylsuccinic anhydride (OSA) modification had slight effects on the morphology or granule size of taro starch, but markedly increased the contact angle from 25.4° to 70.1°. Octenylsuccinylation significantly improved the emulsifying capacity of taro starch granules, and thus OSTS-stabilized emulsions formed at higher DS exhibited better stability. Droplet size distribution results and microscopic observations revealed that OSTS-emulsion prepared at DS of 0.032 had the smallest droplet size and most uniform distribution compared with the other emulsions. The rheological results indicated that both OSTS-emulsions (DS, from 0.009 to 0.032) showed shear-thinning behavior as a non-Newtonian fluid, and the viscosities of emulsions were progressively improved with the increase of DS. Moreover, the G' and G″ values of OSTS-emulsions increased with increasing DS, reflecting the enhanced viscoelastic properties and exhibiting an improved rigidity of the emulsions. The above results suggested that higher-DS favored the formation of superior OSTS-emulsions, and thus OSTS with a high DS (DS ≥ 0.018) can be used for preparing stable Pickering emulsions.

Effects of exposure of adult mice to multi-walled carbon nanotubes on the liver lipid metabolism of their offspring.

Objective: To explore the toxicity of multi-walled carbon nanotubes (MWCNTs) on the liver lipid metabolism of offspring mice and the possible mechanisms involved. Method: Virgin female (16-18 g) and male (18-20 g) C57BL/6 mice were randomly divided into two groups: Control group and Test group. After anesthesia with chloral hydrate, the mice were administered 50 µL saline or dust solution by intratracheal instillation (Control group: 50 µL saline; Test group: 15 mg kg-1 MWCNTs). Mice were injected with these doses once a week for 13 weeks. Then, male and female mice in the same group were allowed to mate to produce offspring. The pups were fed with normal diet until the end of the experiment (12 weeks old). The offspring mice were sacrificed by decapitation to detect the blood biochemistry and the expression of genes and proteins. Results: Compared with the Control group, MWCNTs significantly reduced the weight of offspring mice (male and female) and led to histopathological changes in the liver tissues. The expression of liver fat synthesis gene significantly increased (P < 0.05 or P < 0.01). The expression of genes and proteins involved in the inflammatory reactions appeared to be abnormal (P < 0.05 or P < 0.01). Conclusion: Exposure of adult mice to MWCNTs can affect the expression of fatty acid synthesis genes in the liver tissues of offspring mice, leading to disruption of liver function and accumulation of lipid droplets in the hepatocytes. The imbalance between M1 and M2 liver macrophage phenotypes may be one of the underlying mechanisms of action of MWCNTs leading to disordered fatty acid synthesis in offspring mice.

[Management of sinonasal inverted papilloma: endoscopic approach and lateral rhinotomy].

OBJECTIVE: To compare endoscopic approach with lateral rhinotomy for treatment of the sinonasal inverted papilloma in terms of advantage, indications and limitations of the procedures. METHODS: Eighty-six cases with inverted papilloma were reviewed retrospectively, among which 23 cases underwent transnasal endoscopic procedures including 10 combined with Caldwell-Luc intervention, and 63 cases underwent lateral rhinotomy. The follow-up period ranged from 11 - 36 m (mean 23 m). The data were processed statistically by SPSS 10.0 software. RESULT: Both procedures permitted removal of most sinonasal inverted papilloma. The endoscopic surgery provided an excellent visualization, and preserved a vital anatomic structure and left no facial scar. Lateral rhinotomy was associated with postoperative facial scar or deformity. The recurrence rate in lateral rhinotomy group was 9.5% and in endoscopic approach was 13% (P >0.05). CONCLUSION: Endoscopic approach is favored for the treatment of non-massively extending sinonasal inverted papilloma because of an acceptable recurrence and a better cosmetic results.

[Application of immunofluorescence and sandwich ELISA with double-antibodies in detection of human rabies].

OBJECTIVE: To explore the application of immunofluorescence and sandwich ELISA with double-antibodies in detection of human rabies. METHODS: The cerebrum, cerebellum, brainstem, and hippocampus of four patients died of rabies identified by clinical diagnosis were collected and kept in freezer at -70 degrees C or in formaldehyde solution separately. The rat brain tissue infected by CVS strain of rabies virus was used as a positive control and the brain tissue of a patient died of acute pancreatitis was used as a negative control. RESULTS: Rabies virus was detected in the tissues kept in freezer at -70 degrees C and the positive control but was not detected in the tissues kept in formaldehyde solution and the negative control. CONCLUSION: Immunofluorescence and Sandwich ELISA with double-antibodies could be used in detection of human rabies. The samples should be kept in deep frozen temperature condition instead of in formaldehyde solution.

Liquid-liquid extraction intensification by micro-droplet rotation in a hydrocyclone.

The previous literature reports that using a hydrocyclone as an extractor intensifies the mass transfer and largely reduces the consumption of extractant from 1800-2000 kg h-1 to 30-90 kg h-1. However, the intensification mechanism has not been clear. This paper presents experimental and numerical methods to study the multi-scale motion of particles in hydrocyclones. In addition to the usually considered translational behavior, the high-speed rotation of dispersed micro-spheres caused by the anisotropic swirling shear flow is determined. The rotation speeds of the tested micro-spheres are above 1000 rad s-1, which are much larger than the instantaneous rotation speed in isotropic turbulence. Due to the conical structure of a hydrocyclone, the rotation speed maintains stability along the axial direction. Numerical results show that the particle Reynolds number of micro-droplets in a hydrocyclone is equal to that in conventional extractors, but the particles have high rotation speeds of up to 10,000 rad s-1 and long mixing lengths of more than 1000 mm. Both the rotation of micro-droplets along the spiral trajectories and the intense eddy diffusion in a hydrocyclone contribute to the extraction intensification.

In situ analysis of dynamic laminar flow extraction using surface-enhanced Raman spectroscopy.

In this study, we performed micro-scale dynamic laminar flow extraction and site-specific in situ chloride concentration measurements. Surface-enhanced Raman spectroscopy was utilized to investigate the diffusion process of chloride ions from an oil phase to a water phase under laminar flow. In contrast to common logic, we used SERS intensity gradients of Rhodamine 6G to quantitatively calculate the concentration of chloride ions at specific positions on a microfluidic chip. By varying the fluid flow rates, we achieved different extraction times and therefore different chloride concentrations at specific positions along the microchannel. SERS spectra from the water phase were recorded at these different positions, and the spatial distribution of the SERS signals was used to map the degree of nanoparticle aggregation. The concentration of chloride ions in the channel could therefore be obtained. We conclude that this method can be used to explore the extraction behaviour and efficiency of some ions or molecules that enhance the SERS intensity in water or oil by inducing nanoparticle aggregation.

Microfluidic-based fabrication, characterization and magnetic functionalization of microparticles with novel internal anisotropic structure.

Easy fabrication and independent control of the internal and external morphologies of core-shell microparticles still remain challenging. Core-shell microparticle comprised of a previously unknown internal anisotropic structure and a spherical shell was fabricated by microfluidic-based emulsificaiton and photopolymerization. The interfacial and spatial 3D morphology of the anisotropic structure were observed by SEM and micro-CT respectively. Meanwhile, a series of layer-by-layer scans of the anisotropic structure were obtained via the micro-CT, which enhanced the detail characterization and analysis of micro materials. The formation mechanism of the internal anisotropic structure may be attributed to solution-directed diffusion caused by the semipermeable membrane structure and chemical potential difference between inside and outside of the semipermeable membrane-like polymerized shell. The morphology evolution of the anisotropic structure was influenced and controlled by adjusting reaction parameters including polymerization degree, polymerization speed, and solute concentration difference. The potential applications of these microparticles in microrheological characterization and image enhancement were also proposed by embedding magnetic nanoparticles in the inner core.

Efficient ligase 3-dependent microhomology-mediated end joining repair of DNA double-strand breaks in zebrafish embryos.

DNA double-strand break (DSB) repair is of considerable importance for genomic integrity. Homologous recombination (HR) and non-homologous end joining (NHEJ) are considered as two major mechanistically distinct pathways involved in repairing DSBs. In recent years, another DSB repair pathway, namely, microhomology-mediated end joining (MMEJ), has received increasing attention. MMEJ is generally believed to utilize an alternative mechanism to repair DSBs when NHEJ and other mechanisms fail. In this study, we utilized zebrafish as an in vivo model to study DSB repair and demonstrated that efficient MMEJ repair occurred in the zebrafish genome when DSBs were induced using TALEN (transcription activator-like effector nuclease) or CRISPR (clustered regularly interspaced short palindromic repeats)/Cas9 technologies. The wide existence of MMEJ repair events in zebrafish embryos was further demonstrated via the injection of several in vitro-designed exogenous MMEJ reporters. Interestingly, the inhibition of endogenous ligase 4 activity significantly increased MMEJ frequency, and the inhibition of ligase 3 activity severely decreased MMEJ activity. These results suggest that MMEJ in zebrafish is dependent on ligase 3 but independent of ligase 4. This study will enhance our understanding of the mechanisms of MMEJ in vivo and facilitate inducing desirable mutations via DSB-induced repair.

Developments of subunit and VLP vaccines against influenza A virus.

Influenza virus is a continuous and severe global threat to mankind. The continuously re-emerging disease gives rise to thousands of deaths and enormous economic losses each year, which emphasizes the urgency and necessity to develop high-quality influenza vaccines in a safer, more efficient and economic way. The influenza subunit and VLP vaccines, taking the advantage of recombinant DNA technologies and expression system platforms, can be produced in such an ideal way. This review summarized the recent advancements in the research and development of influenza subunit and VLP vaccines based on the recombinant expression of hemagglutinin antigen (HA), neuraminidase antigen (NA), Matrix 2 protein (M2) and nucleocapsid protein (NP). It would help to get insight into the current stage of influenza vaccines, and suggest the future design and development of novel influenza vaccines.

Genetic modification of baculovirus expression vectors.

As a protein expression vector, the baculovirus demonstrates many advantages over other vectors. With the development of biotechnology, baculoviral vectors have been genetically modified to facilitate high level expression of heterologous proteins in both insect and mammalian cells. These modifications include utilization of different promoters and signal peptides, deletion or replacement of viral genes for increasing protein secretion, integration of polycistronic expression cassette for producing protein complexes, and baculovirus pseudotyping, promoter accommodation or surface display for enhancing mammalian cell targeting gene delivery. This review summarizes the development and the current state of art of the baculovirus expression system. Further development of baculovirus expression systems will make them even more feasible and accessible for advanced applications.

[Human chorionic gonadotrophin on the expression of epidermal growth factor in rat renal tissues].

AIM: To investigate hCG on the expression of epidermal growth factor (EGF) in renal tissues. METHODS: 20 male SD rats weighed 300 - 350 g were injected hCG 200 IU/d for 7 days, and 20 male rats were injected sa-line at equal volume as a control. Kidney tissues were per-formed with immunohistochemical staining to evaluate the distribution of EGF and quantitative PCR (Q-PCR) was used to evaluate the EGF mRNA. RESULTS: Immunohistochemtry showed that the positive rate of EGF in experimental group was significantly higher than that in control group(P<0.01), but Q-PCR results showed no significant difference between two groups ( P > 0. 05). CONCLUSION: hCG increased the concentration of EGF by maturing pre-pro-EGF not expressing EGF from de novo synthesis.

Production of CCHF virus-like particle by a baculovirus-insect cell expression system.

Crimean-Congo Haemorrhagic Fever Virus (CCHFV) is a tick-born virus of the Nairovirus genus within the Bunyaviridae family, which is widespread and causes high fatality. The nucleocapsid of CCHFV is comprised of N proteins that are encoded by the S segment. In this research, the N protein of CCHFV was expressed in insect cells using a recombinant baculovirus. Under an electron microscope, Virus-Like Particles (VLPs) with various size and morphology were observed in cytoplasmic vesicles in the infected cells. Sucrose-gradient purification of the cell lysate indicated that the VLPs were mainly located in the upper fraction after ultracentrifugation, which was confirmed by Western blot analysis and immuno-electron microscopy (IEM).

Serial expression of the truncated fragments of the nucleocapsid protein of CCHFV and identification of the epitope region.

The Crimean-congo hemorrhagic fever virus (CCHFV) is a geographically widespread fatal pathogen. Identification of the epitope regions of the virus is important for the diagnosis and epidemiological studies of CCHFV infections. In this study, expression vectors carrying series truncated fragments of the NP (nucleocapsid protein) gene from the S fragment of CCHFV strain YL04057 were constructed. The recombinant proteins were expressed in E.coli and purified for detection. The antigenic of the truncated fragments of NP was detected with a polyclonal serum (rabbit) and 2 monoclonal (mAbs) (14B7 and 43E5) against CCHFV by Western-blot analyses. The results showed that the three expressed constructs, which all contained the region 235AA to 305AA could be detected by mAbs polyclonal serum. The results suggest that region 235-305 aa of NP is a highly antigenic region and is highly conserved in the NP protein.