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1.
Chaos, Solitons & Fractals ; : 113159, 2023.
Article in English | ScienceDirect | ID: covidwho-2177282

ABSTRACT

In this paper, we investigate the effectiveness of COVID-19 vaccination in controlling the infectivity and mortality of the SARS-CoV-2. Two major variants Delta and Omicron are investigated respectively. The main method used in the research is the multifractal detrended fluctuation analysis (MF-DFA). We use Δα as the evaluation of control effectiveness. In the transmission stages of Delta and Omicron, we observe whether Δα shows a downward trend by gradually expanding the length of time series. Vaccine effectiveness is evaluated using a time series of newly diagnosed patients and newly reported deaths. Data samples are taken from 9 different countries. According to the obtained results, the vaccine controls infectivity and mortality of the virus in the Delta transmission stage, but infectivity control is less effective than mortality. In the Omicron transmission stage, the immune effect of the vaccine is not obvious, which may be related to the high infectivity of Omicron. However, the vaccine is still effective in controlling mortality. We also find that the immune effect of vaccine on Omicron was lower than that of Delta. Finally, we observe that the immune effect of the vaccine in ‘Poland' was abnormal. By analyzing the vaccination curve, we conclude that in ‘Poland', when the growth rate of vaccination rate slowed down, the immune effect of the vaccine was very poor in terms of pathogenicity and lethality. Therefore, we suggest that all countries should continue to strengthen the vaccination rate. A higher or faster growth rate of vaccination rate will help control the infectivity and mortality rate, especially in the effectiveness of controlling mortality. Our research can be used to evaluate the effectiveness of vaccines for epidemic prevention and control, the formulation of epidemic prevention measures and vaccination policies for different countries with respect to their current pandemic situation accordingly.

2.
International Journal of Environmental Research and Public Health ; 20(3):1676, 2023.
Article in English | MDPI | ID: covidwho-2200148

ABSTRACT

This study established a comprehensive evaluation indicator model for the safety culture among residents during COVID-19 and an obstacle degree model for the identification of the major factors affecting the residents' safety culture. The results show that the overall level of the safety culture among residents was 0.6059. Safety education, channels for learning knowledge regarding safety, and implementation of safety management systems are currently the major obstacles affecting safety culture among residents, but there is still space for improvement in the future. Furthermore, the level of safety culture was strongly related to the distance from the infected, because this changes the risk of viral infection. There are also differences in obstacle factors in different regions. Therefore, it is necessary to implement measures targeting the improvement of safety culture in accordance with the risk of viral infection. Strategies for strengthening the safety culture are also given in this study for consideration in strategic decision making with the aim of promoting the improvement of safety culture among residents, which may help to reduce the risk of infection with COVID-19 for residents.

3.
Computers & Industrial Engineering ; : 108893, 2022.
Article in English | ScienceDirect | ID: covidwho-2149480

ABSTRACT

Amid the epidemic outbreaks such as COVID-19, a large number of patients occupy inpatient and intensive care unit (ICU) beds, thereby making the availability of beds uncertain and scarce. Thus, elective surgery scheduling not only needs to deal with the uncertainty of the surgery duration and length of stay in the ward, but also the uncertainty in demand for ICU and inpatient beds. We model this surgery scheduling problem with uncertainty and propose an effective algorithm that minimizes the operating room overtime cost, bed shortage cost, and patient waiting cost. Our model is developed using fuzzy sets whereas the proposed algorithm is based on the differential evolution algorithm and heuristic rules. We set up experiments based on data and expert experience respectively. A comparison between the fuzzy model and the crisp (non-fuzzy) model proves the usefulness of the fuzzy model when the data is not sufficient or available. We further compare the proposed model and algorithm with several extant models and algorithms, and demonstrate the computational efficacy, robustness, and adaptability of the proposed framework.

4.
BMC Pediatr ; 22(1): 452, 2022 Jul 27.
Article in English | MEDLINE | ID: covidwho-1965734

ABSTRACT

BACKGROUND: Pneumonia is a serious problem that threatens the health of newborns. This study aimed to investigate the clinical characteristics of hospitalized term and preterm infants with community-acquired viral pneumonia. METHODS: This was a retrospective analysis of cases of community-acquired viral pneumonia in the Neonatal Department. Nasopharyngeal aspirate (NPA) samples were collected for pathogen detection, and clinical data were collected. We analysed pathogenic species and clinical characteristics among these infants. RESULTS: RSV is the main virus in term infants, and parainfluenza virus (PIV) 3 is the main virus in preterm infants. Patients infected with PIV3 were more susceptible to coinfection with bacteria than those with respiratory syncytial virus (RSV) infection (p < 0.05). Preterm infants infected with PIV3 were more likely to be coinfected with bacteria than term infants (p < 0.05), mainly gram-negative bacteria (especially Klebsiella pneumonia). Term infants with bacterial infection were more prone to fever, cyanosis, moist rales, three concave signs, elevated C-reactive protein (CRP) levels, respiratory failure and the need for higher level of oxygen support and mechanical ventilation than those with simple viral infection (p < 0.05). The incidence of hyponatremia in neonatal community-acquired pneumonia (CAP) was high. CONCLUSIONS: RSV and PIV3 were the leading causes of neonatal viral CAP. PIV3 infection is the main cause of viral CAP in preterm infants, and these individuals are more likely to be coinfected with bacteria than term infants, mainly gram-negative bacteria. Term infants with CAP coinfected with bacteria were more likely to have greater disease severity than those with single viral infections.


Subject(s)
Community-Acquired Infections , Pneumonia, Viral , Respiratory Syncytial Virus Infections , Virus Diseases , Community-Acquired Infections/epidemiology , Humans , Infant , Infant, Newborn , Infant, Premature , Pneumonia, Viral/complications , Pneumonia, Viral/diagnosis , Pneumonia, Viral/epidemiology , Respiratory Syncytial Virus Infections/complications , Respiratory Syncytial Virus Infections/diagnosis , Respiratory Syncytial Virus Infections/epidemiology , Retrospective Studies
5.
BMJ Open ; 12(11): e061803, 2022 11 22.
Article in English | MEDLINE | ID: covidwho-2137722

ABSTRACT

OBJECTIVES: To understand the knowledge, attitude and behaviour of general practitioners (GPs) towards COVID-19 and to provide evidence for improved prevention and control measures against the pandemic. STUDY DESIGN: A cross-sectional study was conducted with 1018 GPs in Shanghai from 21 February to 2 March 2020 using the WeChat platform. METHODS: Stratified random cluster sampling was performed according to the regional division of urban, urban-rural fringe and rural areas. This study used a self-designed mobile questionnaire. The questionnaire collected information on knowledge, attitudes and behaviours regarding COVID-19 prevention and control. RESULTS: A total of 989 questionnaires were declared valid. The average scores of GPs' knowledge, attitude and behaviour towards COVID-19 were 6.14±1.42 (range 0-10), 13.59±4.42 (range 0-25) and 7.82±1.53 (range 0-10), respectively. Multiple linear regression analysis showed that the knowledge score of male GPs was lower than that of female GPs (p=0.002). In addition, the 'attitude' score of female GPs was higher than that of male GPs (p=0.004). The 'behaviour' score of GPs in urban areas was lower than that of GPs in urban-rural fringe areas (p<0.001). The higher the knowledge score, the higher the behavioural score was observed to be (p<0.001). CONCLUSIONS: The scores of knowledge, attitude and behaviour of Shanghai GPs towards COVID-19 were limited at the beginning of the COVID-19 outbreak. As a hopeful measure, the early implementation of proper training programmes for GPs in times of crisis will contribute to disease control and prevention. Lessons learnt from the current pandemic will hopefully help GPs handle similar future challenges and potential novel pandemics.


Subject(s)
COVID-19 , General Practitioners , Male , Female , Humans , Cross-Sectional Studies , Pandemics/prevention & control , COVID-19/epidemiology , COVID-19/prevention & control , Health Knowledge, Attitudes, Practice , China/epidemiology
6.
International Journal of Environmental Research and Public Health ; 19(23):15705, 2022.
Article in English | MDPI | ID: covidwho-2123663

ABSTRACT

Transportation is the main carrier of population movement, so it is significant to clarify how different transportation modes influence epidemic transmission. This paper verified the relationship between different levels of facilities and epidemic transmission by use of the K-means clustering method and the Mann-Whitney U test. Next, quantile regression and negative binomial regression were adopted to evaluate the relationship between transportation modes and transmission patterns. Finally, this paper proposed a control efficiency indicator to assess the differentiated strategies. The results indicated that the epidemic appeared 2-3 days earlier in cities with strong hubs, and the diagnoses were nearly fourfold than in other cities. In addition, air and road transportation were strongly associated with transmission speed, while railway and road transportation were more correlated with severity. A prevention strategy that considered transportation facility levels resulted in a reduction of the diagnoses of about 6%, for the same cost. The results of different strategies may provide valuable insights for cities to develop more efficient control measures and an orderly restoration of public transportation during the steady phase of the epidemic.

7.
Nucleic Acids Res ; 2022 Nov 09.
Article in English | MEDLINE | ID: covidwho-2103098

ABSTRACT

Mitochondrial translation is of high significance for cellular energy homeostasis. Aminoacyl-tRNA synthetases (aaRSs) are crucial translational components. Mitochondrial aaRS variants cause various human diseases. However, the pathogenesis of the vast majority of these diseases remains unknown. Here, we identified two novel SARS2 (encoding mitochondrial seryl-tRNA synthetase) variants that cause a multisystem disorder. c.654-14T > A mutation induced mRNA mis-splicing, generating a peptide insertion in the active site; c.1519dupC swapped a critical tRNA-binding motif in the C-terminus due to stop codon readthrough. Both mutants exhibited severely diminished tRNA binding and aminoacylation capacities. A marked reduction in mitochondrial tRNASer(AGY) was observed due to RNA degradation in patient-derived induced pluripotent stem cells (iPSCs), causing impaired translation and comprehensive mitochondrial function deficiencies. These impairments were efficiently rescued by wild-type SARS2 overexpression. Either mutation caused early embryonic fatality in mice. Heterozygous mice displayed reduced muscle tissue-specific levels of tRNASers. Our findings elucidated the biochemical and cellular consequences of impaired translation mediated by SARS2, suggesting that reduced abundance of tRNASer(AGY) is a key determinant for development of SARS2-related diseases.

8.
Frontiers in public health ; 10, 2022.
Article in English | EuropePMC | ID: covidwho-2073351

ABSTRACT

Background The reinfection rate of SARS-CoV-2 Omicron variant is high;thus, exploring the risk factors for reinfection is important for the effective control of the epidemic. This study aimed to explore the effects of psychological and sleep factors on re-positivity with Omicron. Methods Through a prospective cohort study, 933 adult patients diagnosed with Omicron BA.2.2 infection and testing negative after treatment were included for screening and follow-up. We collected data on patients' demographic characteristics, SARS-CoV-2 Omicron vaccination status, anxiety, depression, and sleep status. Patients underwent nucleic acid testing for SARS-CoV-2 Omicron for 30 days. Regression and Kaplan-Meier analyses were used to determine the risk factors for re-positivity of Omicron. Results Ultimately, 683 patients were included in the analysis. Logistic regression analysis showed that older age (P = 0.006) and depressive status (P = 0.006) were two independent risk factors for Omicron re-positivity. The odds ratios of re-positivity in patients aged ≥60 years and with a Patient Health Questionnaire-9 (PHQ-9) score ≥5 was 1.82 (95% confidence interval:1.18–2.78) and 2.22 (1.27–3.85), respectively. In addition, the time from infection to recovery was significantly longer in patients aged ≥60 years (17.2 ± 4.5 vs. 16.0 ± 4.4, P = 0.003) and in patients with PHQ-9≥5 (17.5 ± 4.2vs. 16.2 ± 4.5, P = 0.026). Kaplan–Meier analysis showed that there was a significantly higher primary re-positivity rate in patients aged ≥60 years (P = 0.004) and PHQ-9 ≥ 5 (P = 0.007). Conclusion This study demonstrated that age of ≥60 years and depressive status were two independent risk factors for re-positivity with Omicron and that these factors could prolong the time from infection to recovery. Thus, it is necessary to pay particular attention to older adults and patients in a depressive state.

9.
Chin J Acad Radiol ; : 1-9, 2022 Oct 11.
Article in English | MEDLINE | ID: covidwho-2060154

ABSTRACT

Purpose: This study aimed to investigate manifestations of the gastric wall and related risk factors in COVID-19 patients with gastrointestinal symptoms by CT. Materials and methods: Two hundred and forty patients diagnosed with COVID-19 by RT-PCR were enrolled from January 2020 to April 2020. Patients showed gastrointestinal symptoms, including nausea, vomiting, or diarrhea. Results of the initial laboratory examination were performed after admission. Chest CT was performed for all patients, with the lower bound including the gastric antrum. The volume of COVID-19 and lungs was segmented, and the ratio was calculated as follows: PV/LV = Volumepneumonia/Volumelungs. Results: Among the 240 patients, 109 presented with gastric wall edema (edema group), and 131 showed no gastric wall edema (non-edema group); the PV/LV values between the two groups were significantly different (P = 0.002). Univariate analysis revealed the following: fibrinogen (Fib), thrombin time (TT), activated partial thromboplastin time (APTT), and albumin (ALB) significantly differed between the two groups (P < 0.05). Binary logistic regression analysis showed that only APTT had a negative effect on gastric wall edema (P = 0.003). Conclusions: SARS-CoV-2 invades the gastrointestinal tract, gastric wall edema is the primary CT manifestation, and gastric wall edema is more likely to occur with a shorter APTT and severe pneumonia, with a slightly longer hospitalization time. Patients with gastric wall edema observed by CT should intervene early, which may improve digestive function, and further strengthen immune potency against COVID-19.

10.
Advanced Functional Materials ; : 1, 2022.
Article in English | Academic Search Complete | ID: covidwho-2047420

ABSTRACT

Severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) surface spike glycoprotein—a major antibody target—is critical for virus entry via engagement of human angiotensin‐converting enzyme 2 (ACE2) receptor. Despite successes with existing vaccines and therapies that primarily target the receptor binding domain (RBD) of the spike protein, the susceptibility of RBD to mutations provides escape routes for the SARS‐CoV‐2 from neutralizing antibodies. On the other hand, structural conservation in the spike protein can be targeted to reduce escape mutations and achieve broad protection. Here, candidate stable immunogens are designed that mimic surface features of selected conserved regions of spike protein through “epitope grafting,” in which the target epitope topology is presented on diverse heterologous scaffolds that can structurally accommodate the spike epitopes. Structural characterization of the epitope‐scaffolds showed stark agreement with computational models and target epitopes. The sera from mice immunized with engineered designs display epitope‐scaffolds and spike binding activity. The utility of the designed epitope‐scaffolds in diagnostic applications is also demonstrated. Taken all together, this study provides an important methodology for targeting the conserved, non‐RBD structural motifs of spike protein for SARS‐CoV‐2 epitope vaccine design and demonstrates the potential utility of “epitope grafting” in rational vaccine design. [ FROM AUTHOR] Copyright of Advanced Functional Materials is the property of John Wiley & Sons, Inc. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full . (Copyright applies to all s.)

11.
Frontiers in cardiovascular medicine ; 9, 2022.
Article in English | EuropePMC | ID: covidwho-2047093

ABSTRACT

While new variants of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) constantly emerge to prolong the pandemic of COVID-19, robust and safe therapeutics are in urgent need. During the previous and ongoing fight against the pandemic in China, Traditional Chinese Medicine (TCM) has proven to be markedly effective in treating COVID-19. Among active ingredients of TCM recipes, small molecules such as quercetin, glabridin, gallic acid, and chrysoeriol have been predicted to target viral receptor angiotensin-converting enzyme 2 (ACE2) via system pharmacology/molecular docking/visualization analyses. Of note, endothelial dysfunction induced by oxidative stress and inflammation represents a critical mediator of acute respiratory distress syndrome (ARDS) and multi-organ injuries in patients with COVID-19. Hence, in the present study, we examined whether quercetin, glabridin, gallic acide and chrysoeriol regulate viral receptors of ACE2 and transmembrane serine protease 2 (TMPRSS2), redox modulator NADPH oxidase isoform 2 (NOX2), and inflammatory protein of monocyte chemoattractant protein-1 (MCP-1) in endothelial cells to mediate therapeutic protection against COVID-19. Indeed, quercetin, glabridin, gallic acide and chrysoeriol completely attenuated SARS-CoV-2 spike protein (S protein)-induced upregulation in ACE2 protein expression in endothelial cells. In addition, these small molecules abolished S protein upregulation of cleaved/active form of TMPRSS2, while native TMPRSS2 was not significantly regulated. Moreover, these small molecules completely abrogated S protein-induced upregulation in NOX2 protein expression, which resulted in alleviated superoxide production, confirming their preventive efficacies against S protein-induced oxidative stress in endothelial cells. In addition, treatment with these small molecules abolished S protein induction of MCP-1 expression. Collectively, our findings for the first time demonstrate that these novel small molecules may be used as novel and robust therapeutic options for the treatment of patients with COVID-19, via effective attenuation of S protein induction of endothelial oxidative stress and inflammation.

12.
Pulm Circ ; 12(3): e12130, 2022 Jul.
Article in English | MEDLINE | ID: covidwho-2047923

ABSTRACT

The Coronavirus disease 2019 (COVID-19) pandemic has severely affected the lives of people around the world, especially some patients with severe chronic diseases. This study aims to evaluate the impact of the COVID-19 outbreak from December 2019 to April 2020 on treating patients with PH. A questionnaire regarding the medical condition of PH patients during the COVID-19 pandemic was designed by PH diagnostic experts in The First Affiliated Hospital of Guangzhou Medical University, China Respiratory Center. One hundred and fifty-six subjects with PH from non-Hubei regions in China were invited to participate in this survey online. 63.4% (n = 99) of them had difficulty seeing a doctor, and the main reason was fear of contracting severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in the hospital. Medical treatment was affected in 25% (n = 39) of patients, and who lived in rural areas, and discontinued medical therapy for financial reasons were at a higher risk of medical treatment being affected. Patients who reduced nutrition, and had difficulty seeing a doctor were more likely to get deteriorated. During the epidemic, the hospitalization rate of PH patients was 33.33%. Patients with aggravated PH had a high risk of hospitalization (odds ratio [OR] = 2.844), while patients who visited a doctor during the epidemic reduced the risk of hospitalization (OR = 0.33). In conclusion, during the COVID-19 pandemic, PH patients had difficulty seeing a doctor, and their medical treatment was affected, even worsened, and increased the risk of hospitalization.

13.
Pulmonary circulation ; 12(3), 2022.
Article in English | EuropePMC | ID: covidwho-2045191

ABSTRACT

The Coronavirus disease 2019 (COVID‐19) pandemic has severely affected the lives of people around the world, especially some patients with severe chronic diseases. This study aims to evaluate the impact of the COVID‐19 outbreak from December 2019 to April 2020 on treating patients with PH. A questionnaire regarding the medical condition of PH patients during the COVID‐19 pandemic was designed by PH diagnostic experts in The First Affiliated Hospital of Guangzhou Medical University, China Respiratory Center. One hundred and fifty‐six subjects with PH from non‐Hubei regions in China were invited to participate in this survey online. 63.4% (n = 99) of them had difficulty seeing a doctor, and the main reason was fear of contracting severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) in the hospital. Medical treatment was affected in 25% (n = 39) of patients, and who lived in rural areas, and discontinued medical therapy for financial reasons were at a higher risk of medical treatment being affected. Patients who reduced nutrition, and had difficulty seeing a doctor were more likely to get deteriorated. During the epidemic, the hospitalization rate of PH patients was 33.33%. Patients with aggravated PH had a high risk of hospitalization (odds ratio [OR] = 2.844), while patients who visited a doctor during the epidemic reduced the risk of hospitalization (OR = 0.33). In conclusion, during the COVID‐19 pandemic, PH patients had difficulty seeing a doctor, and their medical treatment was affected, even worsened, and increased the risk of hospitalization.

14.
Front Pharmacol ; 13: 936925, 2022.
Article in English | MEDLINE | ID: covidwho-2022836

ABSTRACT

Background: Coronavirus disease 2019 (COVID-19) was declared a global pandemic in March 2020 by the World Health Organization (WHO). As of July 2, 2022, COVID-19 has caused more than 545 million infections and 6.3 million deaths worldwide, posing a significant threat to human health. Currently, there is still a lack of effective prevention and control strategies for the variation and transmission of SARS-CoV-2. Traditional Chinese medicine (TCM), which has a unique theoretical system, has treated various conditions for thousands of years. Importantly, recent studies have revealed that TCM contributed significantly to COVID-19. SanHanHuaShi (SHHS) granules, a Chinese herbal medicine, which has been included in Protocol for the Diagnosis and Treatment of Novel Coronavirus Disease 2019 (6th to 9th editions) issued by the National Health Commission of China and used to prevent and treat COVID-19 disease. A previous retrospective cohort study showed that SHHS could significantly reduce the severity of mild and moderate COVID-19. However, there is an absence of high-quality randomized controlled clinical studies to confirm the clinical effectiveness of SHHS. Therefore, a clinical study protocol and a statistical analysis plan were designed to investigate the efficacy and safety of SHHS for the prevention and treatment of COVID-19. This study will increase the integrity and data transparency of the clinical research process, which is of great significance for improving the practical application of SHHS granules in the future. Methods and analysis: The study was designed as a 7-day, randomized, parallel controlled, open-label, noninferiority clinical trial of positive drugs. A total of 240 patients with mild and moderate COVID-19 will be enrolled and randomly assigned to receive SanHanHuaShi granules or LianHuaQingWen granules treatment in a 1:1 ratio. Disease classification, vital signs, SARS-CoV-2 nucleic acid testing, symptoms, medications, adverse events, and safety evaluations will be recorded at each visit. The primary outcome will be the clinical symptom recovery rate. Secondary outcomes will include the recovery time of clinical symptoms, negative conversion time of SARS-CoV-2 nucleic acid test negative conversion rate, hospitalization time, antipyretic time, rate of conversion to severe patients, and time and rate of single symptom recovery. Adverse incidents and safety assessments will be documented. All data will be analyzed using a predetermined statistical analysis plan, including our method for imputation of missing data, primary and secondary outcome analyses, and safety outcomes. Discussion: The results of this study will provide robust evidence to confirm the effectiveness and safety of SHHS in the treatment of COVID-19. Clinical Trial Registration: http://www.chictr.org.cn. Trial number: ChiCTR2200058080. Registered on 29 March 2022.

15.
Front Immunol ; 13: 917141, 2022.
Article in English | MEDLINE | ID: covidwho-2022706

ABSTRACT

COVID-19 caused by SARS-CoV-2 can cause various systemic diseases such as acute pneumonia with cytokine storm. Constituted of necroptosis, pyroptosis, and ferroptosis, regulated necrosis constitutes the cell death patterns under the low apoptosis condition commonly observed in COVID-19. Regulated necrosis is involved in the release of cytokines like TNF-α, IL-1 ß, and IL-6 and cell contents such as alarmins, PAMPs, and DAMPs, leading to more severe inflammation. Uncontrolled regulated necrosis may explain the poor prognosis and cytokine storm observed in COVID-19. In this review, the pathophysiology and mechanism of regulated necrosis with the double-edged sword effect in COVID-19 are thoroughly discussed in detail. Furthermore, this review also focuses on the biomarkers and potential therapeutic targets of the regulated necrosis pathway in COVID-19, providing practical guidance to judge the severity, prognosis, and clinical treatment of COVID-19 and guiding the development of clinical anti-SARS-CoV-2 drugs.


Subject(s)
COVID-19 , Apoptosis/physiology , Cytokine Release Syndrome , Humans , Necrosis , SARS-CoV-2
16.
Fluctuation & Noise Letters ; : 1, 2022.
Article in English | Academic Search Complete | ID: covidwho-2001918

ABSTRACT

This paper investigates the presence and asymmetry of cross-correlations between agricultural futures markets in China and the US as well as the impact of price support policies and public emergencies (Sino–US trade conflict and COVID-19 pandemic) on the cross-correlations by the multifractal methods. The results show that the fluctuation characteristics and conduction directions of cross-correlations are asymmetric. The price fluctuations of soybean and corn futures in China are easier to be affected by the US soybean and corn futures. We find that the cross-correlations are multifractal under different price support policies and pubic emergencies. The price support policies with greater interventions on soybean and corn prices have aggravated the complexity of cross-correlations between the two futures markets in China and the US. The soybean and corn futures in China are hardly correlated to the US futures under the dual effect of the Sino–US trade conflict and the COVID-19 pandemic. The Sino–US trade conflict strengthens the complexity of cross-correlation for soybean futures and weakens it for corn futures, while the COVID-19 pandemic enhances the complexity of cross-correlations for soybean and corn futures. In addition, the fat-tailed probability distributions in different price support policy and public emergency periods have a dominant influence on the multifractality of cross-correlations. [ FROM AUTHOR] Copyright of Fluctuation & Noise Letters is the property of World Scientific Publishing Company and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full . (Copyright applies to all s.)

17.
PLoS Pathog ; 18(7): e1010660, 2022 07.
Article in English | MEDLINE | ID: covidwho-1993526

ABSTRACT

Coxiella burnetii is the etiological agent of the zoonotic disease Q fever, which is featured by its ability to replicate in acid vacuoles resembling the lysosomal network. One key virulence determinant of C. burnetii is the Dot/Icm system that transfers more than 150 effector proteins into host cells. These effectors function to construct the lysosome-like compartment permissive for bacterial replication, but the functions of most of these effectors remain elusive. In this study, we used an affinity tag purification mass spectrometry (AP-MS) approach to generate a C. burnetii-human protein-protein interaction (PPI) map involving 53 C. burnetii effectors and 3480 host proteins. This PPI map revealed that the C. burnetii effector CBU0425 (designated CirB) interacts with most subunits of the 20S core proteasome. We found that ectopically expressed CirB inhibits hydrolytic activity of the proteasome. In addition, overexpression of CirB in C. burnetii caused dramatic inhibition of proteasome activity in host cells, while knocking down CirB expression alleviated such inhibitory effects. Moreover, we showed that a region of CirB that spans residues 91-120 binds to the proteasome subunit PSMB5 (beta 5). Finally, PSMB5 knockdown promotes C. burnetii virulence, highlighting the importance of proteasome activity modulation during the course of C. burnetii infection.


Subject(s)
Coxiella burnetii , Q Fever , Bacterial Proteins/genetics , Bacterial Proteins/metabolism , Host-Pathogen Interactions , Humans , Proteasome Endopeptidase Complex/genetics , Proteasome Endopeptidase Complex/metabolism , Protein Interaction Maps , Q Fever/metabolism , Vacuoles/metabolism
18.
Autophagy ; : 1-10, 2022 Aug 11.
Article in English | MEDLINE | ID: covidwho-1984891

ABSTRACT

The COVID-19 pandemic has caused substantial losses worldwide in people's lives, health, and property. Currently, COVID-19 is still prominent worldwide without any specific drug treatment. The SARS-CoV-2 pathogen is the cause of various systemic diseases, mainly acute pneumonia. Within the pathological process, neutrophils are recruited to infected sites, especially in the lungs, for the first stage of removing invading SARS-CoV-2 through a range of mechanisms. Macroautophagy/autophagy, a conserved autodegradation process in neutrophils, plays a crucial role in the neutrophil phagocytosis of pathogens. NETosis refers to neutrophil cell death, while auto-inflammatory factors and antigens release NETs. This review summarizes the latest research progress and provides an in-depth explanation of the underlying mechanisms of autophagy and NETosis in COVID-19. Furthermore, after exploring the relationship between autophagy and NETosis, we discuss potential targets and treatment options. This review keeps up with the latest research on COVID-19 from neutrophil autophagy and NETosis with a new perspective, which can guide the urgent development of antiviral drugs and provide guidance for the clinical treatment of COVID-19.Abbreviations: AKT1: AKT serine/threonine kinase 1; AMPK: AMP-activated protein kinase; AP: autophagosome; ARDS: acute respiratory distress syndrome; ATG: autophagy related; BECN1: beclin 1; cfDNA: cell-free DNA; COVID-19: coronavirus disease 2019; CQ: chloroquine; DMVs: double-membrane vesicles; ELANE/NE: elastase, neutrophil expressed; F3: coagulation factor III, tissue factor; HCQ: hydroxychloroquine; MAP1LC3/LC3: microtubule associated protein 1 light chain of 3; MPO: myeloperoxidase; MTORC1: mechanistic target of rapamycin kinase complex 1; NETs: neutrophil traps; NSP: nonstructural protein; PI3K: class I phosphoinositide 3-kinase; PtdIns3K: class III phosphatidylinositol 3-kinase; PtdIns3P: phosphatidylinositol-3-phosphate; ROS: reactive oxygen species; SARS-CoV-2: severe acute respiratory syndrome coronavirus 2; SKP2: S-phase kinase associated protein 2; TCC: terminal complement complex; ULK1: unc-51 like.

19.
J Mol Graph Model ; 117: 108306, 2022 Dec.
Article in English | MEDLINE | ID: covidwho-1983500

ABSTRACT

The Coronavirus Disease 2019 (COVID-19), caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, has created unprecedented public health and economic crises around the world. SARS-CoV-2 2'-O-methyltransferase (nsp16) adds a "cap" to viral RNA to maintain the stability of viral RNA, and inhibition of nsp16 activity may reduce viral proliferation, making this protein an attractive drug target. Here, we report the identification of several small molecule inhibitors of nsp16 by virtual screening. First, the nsp16-sinefungin complex (PDB ID: 6WKQ) was selected from the protein data bank. Asp6912, Cys6913, Asp6897 and Asp6928 were determined to be the key amino acids for sinefungin binding in the crystal structure of nsp16-sinefungin complex by molecular dynamics simulation. The complex structures in the stable binding trajectory of nsp16-sinefungin were than clustered through molecular dynamics RMSD analysis. Six clusters were generated, and six representative structures were selected to construct the pharmacophore based on the structure. These six pharmacophores were superimposed on the binding pocket to simplify and pick the common characteristics. The compounds obtained by the pharmacophore screening from Bionet and Chembiv databases were docked into the nsp16 active pocket. The candidate compounds were selected according to the molecular docking score and then screened by MM/GBSA. Finally, four candidate compounds were obtained. Four sets of 150ns molecular dynamics simulations were performed to determine whether candidate compounds could maintain stable interactions with key amino acids. The results of MD and MM/PBSA energy decomposition indicated that C1 and C2 could form a stable complex system with nsp16, and could form strong hydrogen bonds and salt bridges with the key amino acid Asp6897 and Asp6928. This study thus identifies and attempts to validate for the first time the potential inhibitory activities of C1 and C2 against nsp16, allowing the development of potent anti-COVID-19 drugs and unique treatment strategies.


Subject(s)
COVID-19 , SARS-CoV-2 , Amino Acids , COVID-19/drug therapy , Humans , Methyltransferases , Molecular Docking Simulation , Molecular Dynamics Simulation , RNA, Viral , Viral Nonstructural Proteins/chemistry
20.
Shanghai Journal of Preventive Medicine ; 33(12):1116-1120, 2021.
Article in Chinese | CAB Abstracts | ID: covidwho-1975561

ABSTRACT

Objective: To analyze the timeliness of health science popularization during the outbreak of coronavirus disease 2019 (COVID-19) and its correlation with the epidemic situation and policies.

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