Zirconium-Based Metal-Organic Frameworks as Reusable Antibacterial Peroxide Carriers for Protective Textiles

Countries around the world have sought efficient protective coverings, including masks, gowns, and fabrics, for air purification to protect people against infectious diseases. However, the demand for significant quantities of disposable protective textiles poses a global challenge, especially when the production of protective gear is suspended due to COVID-19 outbreaks in factories and along supply lines. Therefore, the development of reusable, self-decontaminating protective masks and coverings loaded with disinfectants, such as antibacterial peroxide species, presents an attractive strategy to fight against bacteria risks. In this work, we incorporated persulfate ions, which serve as stable active peroxide precursors, into two porous zirconium-based metal-organic frameworks (Zr-MOFs), enabling these materials to act as regenerable reservoirs for the slow release of biocidal hydrogen peroxide upon hydrolysis by contact with humid air. Single-crystal X-ray diffraction studies reveal the two different coordination motifs for the persulfate ions, which can either bridge between two adjacent nodes or coordinate to a single node depending on both the node connectivity and the distances between open metal sites. The active peroxide precursors within the porous Zr-MOF carriers are stable during storage and easily regenerated once consumed. Importantly, these persulfate-loaded Zr-MOFs can be integrated onto textiles using a facile aqueous in-situ growth procedure, and these composites demonstrate potent and reusable biocidal activity against both Gram-negative bacteria and Gram-positive bacteria. Overall, this approach presents a viable strategy to develop robust protective textiles capable of rapidly deactivating pathogens.

Protection against Chemical Warfare Agents and Biological Threats Using Metal-Organic Frameworks as Active Layers

The SARS-CoV-2 pandemic outbreak and the unfortunate misuse of toxic chemical warfare agents (CWAs) highlight the importance of developing functional materials to protect against these chemical and pathogen threats. Metal-organic frameworks (MOFs), which comprise a tunable class of crystalline porous materials built from inorganic nodes and organic linkers, have emerged as a class of heterogeneous catalysts capable of rapid detoxification of multiple classes of these harmful chemical or biological hazards. In particular, zirconium-based MOFs (Zr-MOFs) feature Lewis acidic nodes that serve as active sites for a wide range of catalytic reactions, including the hydrolysis of organophosphorus nerve agents within seconds in basic aqueous solutions. In addition, postsynthetic modification of Zr-MOFs enables the release of active species capable of reacting with and deactivating harmful pathogens. Despite this impressive performance, utilizing Zr-MOFs in powder form is not practical for application in masks or protective uniforms. To address this challenge, our team sought to develop MOF/fiber composite systems that could be adapted for use under realistic operating conditions to protect civilians, military personnel, and first responders from harmful pathogens and chemical warfare agents. Over the last several years, our group has designed and fabricated reactive and biocidal MOF/fiber composites that effectively capture and deactivate these toxic species. In this Account, we describe the evolution of these porous and reactive MOF/fiber composites and focus on key design challenges and considerations. First, we devised a scalable method for the integration of Zr-MOFs onto textile substrates using aqueous precursor solutions and without using pretreated textiles, highlighting the potential scalability of this method. Moving beyond standard textiles, we also developed a microbial synthesis strategy to prepare hierarchically porous MOF/bacterial cellulose nanofiber composite sponges that can both capture and detoxify nerve agents when exposed to contaminated gas flows. The mass loading of the MOF in the nanofibrous composite sponge is up to 90%, affording higher work capacities compared to those of textile-fiber-based composites with relatively lower MOF loadings. Next, we demonstrated that heterogeneous polymeric bases are suitable replacements for volatile liquid bases typically used in solution-phase reactions, and we showed that these composite systems are capable of effectively hydrolyzing nerve agents in the solid state by using only water that is present as humidity. Moreover, incorporating a reactive dye precursor into the composite affords a dual function sensing and detoxifying material that changes color from white to orange upon reaction with the byproduct following nerve agent hydrolysis, demonstrating the versatility of this platform for use in decontamination applications. We then created chlorine-loaded MOF/fiber composites that act as biocidal and reactive textiles that are capable of not only detoxifying sulfur-mustard-based chemical warfare agents and simulants but also deactivating both bacteria and the SARS-CoV-2 virus within minutes of exposure. Finally, we synthesized a mixed-metal Ti/Zr-MOF coating on cotton fibers to afford a photoactive biocidal cloth that shows fast and broad-spectrum biocidal performance against viruses and Gram-positive and Gram-negative bacteria under visible light irradiation. Given the tunable, multifunctional nature of these MOF/fiber composites, we believe that this Account will offer new insights for the rational design and preparation of functional MOF/fiber composites and pave the way toward the development of next-generation reactive and protective textiles.

Study on pathogen spectrum of 1,046 hospitalized children with respiratory tract infections during COVID-19

Objectives: This study aimed to describe the pathogen spectrum of bacteria and viruses of RTIs in hospitalized children during the Coronavirus disease 2019 (COVID-19) epidemic in Shenzhen. Method(s): From October 2020 to October 2021, the results of pathogenic tests causing RTIs were retrospectively analyzed in hospitalized children in Shenzhen Luohu Hospital Group. Result(s): 829 sputum samples for bacterial isolation and 1,037 nasopharyngeal swabs for virus detection in total. The positive detection rate (PDR) of bacteria was 42.1%. Staphylococcus aureus (18.8%) was the predominant bacteria detected in positive cases, with Moraxella catarrhalis (10.9%), Streptococcus pneumoniae (9.5%) following. The PDR of the virus was 65.6%. The viruses ranking first to third were Human Rhinovirus (HRV), Respiratory syncytial virus (RSV), and Human Parainfluenza (HPIV), with rates of 28.0, 18.1, and 13.5%, respectively. Children under 3 years were the most susceptible population to RTIs. The pathogens of S. aureus, M. catarrhalis, S. pneumoniae, HRV, and HPIV were more prevalent in autumn. Meanwhile, RSV had a high rate of infection in summer and autumn. S. aureus and HRV had higher co-infection rates. Conclusion(s): Our findings demonstrate the pathogen spectrum of 1,046 hospitalized children with RTIs in Shenzhen, China, during the COVID-19 outbreak.Copyright © 2022 the author(s), published by De Gruyter, Berlin/Boston.

Clinical characteristics and serum IgG, IgM antibody manifestations of patients infected with SARS-CoV-2 B.1.1.529 (Omicron) variant strain

Objective To analyze the clinical characteristics and changes of serum IgG, IgM antibodies in patients infected with the SARS-CoV-2 B.1.1.529 (Omicron) variant. Methods The clinical data of 82 patients with SARS-CoV-2 B.1.1.529 variant was analyzed retrospectively. Based on the presence of pneumonia on chest CT, the patients were divided into pneumonia group and non-pneumonia group. Serum IgG, IgM antibodies were observed at 5 time points T1 (1~<4 d), T2 (4~<8 d), T3 (8~<15 d), T4 (15~<22 d) and T5 (22~<30 d) after admission. Results Among the 82 patients infected with the SARSCoV-2 B.1.1.529 variant strain, there were 62 cases of cough, 31 cases of fever, 33 cases of throat discomfort, 5 cases of muscle soreness and 3 cases of diarrhea. The serum IgG antibody levels at 5 time points were 50.22 (142.20) AU/mL, 326.50 (220.63) AU / mL, 368.23 (76.21) AU / mL, 368.65 (79) AU / mL, and 385.26 (113.10) AU / mL, respectively. The level of serum IgG antibody in the pneumonia group was lower than that of the non-pneumonia group at T1 and T4 time points, and the differences were statistically significant (P<0.05), the positive rate of serum IgG antibody in the pneumonia group was lower than that of the non-pneumonia group at the T1 time point, and the difference was statistically significant (P<0.05) . The serum IgM antibody levels at 5 time points were 0.41 (0.81) AU/mL, 0.95 (1.62) AU/mL, 1.09 (2.42) AU/mL, 0.74 (3) AU/mL, and 0.81 (3.10) AU / mL respectively, and there was no significant difference between the two groups. Conclusion The clinical symptoms of patients infected with the SARS-CoV-2 B.1.1.529 variant strain are mild. Serum IgG antibodies increased after infection, but there are some differences between the pneumonia group and the non-pneumonia group, whether serum IgG has a protective effect needs further research;the serum IgM antibodies do not increase highly after infection, there are some differences between individuals. © 2022 Editorial Office of Chinese Journal of Schistosomiasis Control. All rights reserved.

Will Oil Price Volatility Cause Market Panic?

It is generally known that violent oil price volatility will cause market panic;however, the extent to which is worthy of empirical test. Firstly, this paper employs the TVP-VAR model to analyze the time-varying impacts of oil price volatility on the panic index using monthly data from January 1990 to November 2021. Then, after using the SVAR model to decompose the oil price volatility, this paper uses the PDL model to analyze the heterogeneous impacts of oil price volatility from different sources. Finally, based on the results of oil decomposition, this paper uses the TARCH model to analyze the asymmetric impacts of oil price volatility in different directions. The results show that: (1) oil price volatility can indeed cause market panic, and these impacts exhibit time-varying characteristics;(2) oil price volatility from different sources has different impacts on the panic index, and the order from high to low is oil-specific demand shocks, supply shocks, and aggregate demand shocks;and (3) oil price volatility has asymmetric impacts on the panic index, and positive shocks have greater impacts than negative.

[Clinical characteristics and vaccination status of SARS-CoV-2 Omicron variant infected children].

Objective: To investigate the clinical characteristics and vaccination status of SARS-CoV-2 Omicron variant infected children. Methods: A total of 105 children infected with Omicron variant admitted to Tianjin Haihe Hospital (designated referral hospital for SARS-CoV-2 infection in Tianjin) from January 8, 2022 to February 3 were included for a retrospective study. The cases were divided into pneumonia group and non-pneumonia group according to chest imaging. Based on the doses of inactivated SARS-CoV-2 vaccine, the children who completed SARS-CoV-2 antibody test within 3 days after hospitalization were divided into 2 dose group and<2 dose group.Rank sum test and Chi-square test were used for the comparison between the groups. Results: The age of these 105 children was 10 (8, 11) years on admission, 53 children were males and 52 were females. Eighty-seven cases (82.9%) had mild symptoms, 13 cases (12.4%) had common symptoms and 5 cases (4.8%) were asymptomatic. Ninety-one cases (86.7%) completed 2 doses vaccination. The clinical symptoms were characterized by cough (74 cases, 70.5%), fever (58 cases, 55.2%), sore or dry throat (34 cases, 32.4%), nasal congestion (28 cases, 26.7%), rhinorrhea (23 cases, 21.9%). None of the children received antivirals, steroids, immunosuppressant or oxygen therapy. Seventy-six cases(72.4%) received traditional Chinese medicine treatment. The pneumonia group had a higher rate of positive SARS-CoV-2 IgG within 1 day after admission (13/13 vs. 87.0% (80/92), χ2=42.81, P<0.001) than the non-pneumonia group. Among the 62 children who had serial SARS-CoV-2 antibody tests within 3 days after hospitalization, Compared to the<2 dose group, the 2 dose group had a higher rate of nucleic acid conversion within 16 days after onset and a higher rate of positive SARS-CoV-2 IgG 1 day after admission and 3 days after hospitalization (96.4% (54/56) vs. 4/6, 100.0% (56/56) vs. 2/6, 100.0% (56/56) vs. 3/6, all P<0.05). Conclusions: Most children infected with Omicron variant have mild symptoms, mainly respiratory infection symptoms. The proportion of SARS-CoV-2 antibody IgG positive in children who have received 2 doses of inactivated SARS-CoV-2 vaccines is higher,and the time of whose nucleic acid conversion may be shortened.

Interpreting the B-cell receptor repertoire with single-cell gene expression using Benisse

B-cell receptors (BCRs) and their impact on B cells play a vital role in our immune system;however, the manner in which B cells are activated by BCRs are still poorly understood. Ze Zhang and colleagues present a graph-based method that connects BCR and single B-cell RNA sequencing data and identifies notable coupling between BCR and B-cell expression in COVID-19. B-cell receptors (BCRs) are a crucial player in the development and activation of B cells, and their mature forms are secreted as antibodies, which execute functions such as the neutralization of invading pathogens. All current analytical approaches for BCRs solely investigate the BCR sequences and ignore their correlations with the transcriptomics of the B cells, yielding conclusions of unknown functional relevance regarding the roles of BCRs and B cells, and could generate biased interpretation. Many single-cell RNA-sequencing (scRNA-seq) techniques can now capture both the gene expression and BCR of each B cell, which could potentially address this issue. Here, we investigated 43,938 B cells from 13 scRNA-seq datasets with matched scBCR sequencing, and we observed an association between the BCRs and the B cells' transcriptomics. Motivated by this, we developed the Benisse model (BCR embedding graphical network informed by scRNA-seq) to provide refined analyses of BCRs guided by single-cell gene expression. Benisse revealed a gradient of B-cell activation along BCR trajectories. We discovered a stronger coupling between BCRs and B-cell gene expression during COVID-19 infections. We found that BCRs form a directed pattern of continuous and linear evolution to achieve the highest antigen targeting efficiency, compared with the convergent evolution pattern of T-cell receptors. Overall, a simultaneous digestion of the BCR and gene expression of B cells, viewed through the lens of Benisse, will lead to a more insightful interpretation of the functional relevance of the BCR repertoire in different biological contexts.

[Epidemiological characteristics of imported COVID-19 cases in Beijing].

Objective: To analyze the epidemiological characteristics of imported COVID-19 cases and the effect of vaccination on virus load and disease severity of the cases in Beijing. Methods: The data of the imported COVID-19 cases in Beijing were collected from the National Notifiable Infectious Disease Reporting System of China Information for Disease Control and Prevention and Epidemiology investigation. The data were processed and analyzed by Excel 2010 and SPSS 22.0. Results: From June 1 to September 30, 2021, a total of 171 imported COVID-19 cases were reported in Beijing, of which 66.67% (114/171) were asymptomatic. The cases were mainly from the Philippines, the United Arab Emirates, the United Kingdom and the Russian Federation, accounting for 67.84% (116/171). The male to female ratio of the cases was 2∶1 (114∶57). The median age M (Q1, Q3) of the cases was 28 (23, 36) years. The cases of Chinese accounted for 80.12% (137/171). The sequencing of the whole genome of the virus in 47 imported COVID-19 cases showed that the proportion of Delta variant was 76.60% (36/47). The COVID-19 vaccination coverage rate in the cases was 60.82% (104/171), but the full vaccination coverage rate was 53.80% (92/171). In the imported COVID-19 cases, 13.53% (23/170) were screened to be SARS-CoV-2 nucleic acid positive on the day when they arrived in Beijing, and all the cases were positive for 2019-nCoV nucleic acid within 28 days. The severity of the disease was higher in the unvaccinated group than in the partially vaccinated group and fully vaccinated group (P<0.001). In the unvaccinated group, there were 1 severe case and 1 critical case. The median Ct values M (Q1, Q3) of N gene and ORFlab gene in unvaccinated group were 32.51 (23.23, 36.06) and 32.78 (24.00, 36.38), respectively. There was no significant difference in the median of double-gene Ct value between the partially vaccinated group and the fully vaccinated group. Conclusions: During the study period, most of the imported COVID-19 cases in Beijing were asymptomatic. No matter vaccinated or not, the viral loads in the COVID-19 cases were similar, but the vaccination could reduce the severity of the disease.

Reactive force field-based molecular dynamics simulation of the interaction between plasma reactive oxygen species and the receptor-binding domain of the spike protein in the capsid protein of SARS-CoV-2

Under the pressures of the current global pandemic, researchers have been working hard to find a reliable way to suppress infection by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and prevent the spread of COVID-19. Studies have shown that the recognition and binding of human angiotensin-converting enzyme 2 by the receptor-binding domain (RBD) of the spike protein on the surface of SARS-CoV-2 is a crucial step in viral invasion of human receptor cells, and blocking this process could inhibit the virus from invading normal human cells. Plasma treatment can disrupt the structure of the RBD and effectively block the binding process. However, the mechanism by which plasma blocks recognition and binding is not clear. In this study, the reaction between reactive oxygen species (ROS) in plasma and a molecular model of the RBD was simulated using a reactive molecular dynamics method. The results showed that the destruction of the RBD by ROS was triggered by hydrogen ion reactions: O and OH ed H atoms from the RBD, while the H atoms of H2O2 and HO2 were ed by the RBD. This hydrogen ion resulted in the breakage of C-H, N-H, O-H and C=O bonds and the formation of C=C and C=N bonds. The addition reaction of OH increased the number of O-H bonds and caused the formation of C-O, N-O and O-H bonds. The dissociation of N-H bonds led to the destruction of the original peptide bond structure and amino acid residues, changed the type of amino acid residues and caused the conversion of N-C and N=C and C=O and C-O. The simulation partially elucidated the microscopic mechanism of the interaction between ROS in plasma and the capsid protein of SARS-CoV-2, providing theoretical support for the control of SARS-CoV-2 infection by plasma, a contribution to overcoming the global pandemic.

[Survey on source of infection of the first local outbreak caused by SARS-CoV-2 Alpha variant in China].

Objective: To investigate the epidemiological characteristics and the chain of infection of a local outbreak, which was the first outbreak caused by severe acute respiratory syndrome corona virus 2 Alpha variant in China and occurred in Daxing district, Beijing. Methods: Epidemiological investigation and big data technology were used to verify the exposure points of the cases. Close contacts were traced from the exposure points, and their human and environmental samples were collected for nucleic acid tests. Serum samples were collected from key persons for antibody detection. Results: A total of 33 corona virus disease 2019(COVID-19) cases were reported in the local outbreak, from January 17, 2021 to January 29, 2021 in Daxing district, Beijing, and there was epidemiological association in 32 cases. Except for one case who was infected in the workplace, other cases were all infected in the community and family. All cases involved 14 families, of which 6 families were all infected. The attack rate of all family members was 69%(33/48), and the secondary attack rate was 56%(19/34). There was no obvious source of infection found after the investigation of entry-exit personnel and goods. Conclusion: The first outbreak caused by severe acute respiratory syndrome corona virus 2 Alpha variant in China is found and handled in time, and thus the scope of influence is limited, but the family clustering characteristics are more obvious than previous outbreaks.

Physical activity and sedentary behaviour among children and adolescents with intellectual disabilities during the COVID-19 lockdown in China.

BACKGROUND: In the wake of the COVID-19 pandemic, preliminary research has reported a significant decline in physical activity (PA) and an increase in sedentary behaviour (SB) among typically developed children and adolescents. Limited research has looked at the current situation of PA and SB during this pandemic among children and adolescents with intellectual disabilities (ID). This study investigated the situations about PA and SB among school-aged children and adolescents with ID on China's mainland during the COVID-19 outbreak. METHODS: In total, 837 parents of children and adolescents (ages 6-18 years) with ID from 15 special education schools of Shandong Province in China were recruited through convenience sampling in the study. Parents reported PA and SB among children and adolescents with ID through the Children's Leisure Activities Study Survey-Chinese version (CLASS-C) online questionnaires. RESULTS: From parents' reports, Chinese children and adolescents with ID during the COVID-19 pandemic participated in approximately 10 min of moderate-to-vigorous physical activity, and engaged in approximately 530 min of SB every day. Meanwhile, only 17.4% of children and adolescents with ID were able to achieve the recommendation of 60 min of daily moderate-to-vigorous physical activity and 76.1% of children and adolescents with ID spent more than 2 h on SB per day. Additionally, the problems of decrease PA and excessive SB were more prominent in older adolescents with ID compared with younger children with ID. CONCLUSION: In China, the low level of PA and high level of SB is particularly evident in children and adolescents with ID during the outbreak of COVID-19. The great majority of children and adolescents with ID did not meet the recommended amount of PA while undergoing excessive SB under the long-term home quarantine environment. Therefore, immediate attention and great effort should be made to deal with this severe situation among this vulnerable population in the mainland of China.

[Epidemiological characteristics of COVID-19 cases in outbreak in Xinfadi market in Beijing].

Objective: To understand the epidemiological characteristics of COVID-19 cases, including asymptomatic cases and symptomatic cases, in the outbreak in Xinfadi market in Beijing. Methods: Data and epidemiological survey reports of COVID-19 cases in Xinfadi market in Beijing were extracted from China's Infectious Disease Information System. Epidemiological characteristics of symptomatic cases and asymptomatic cases were analyzed and compared by using software SPSS 19.0. Results: From June 11 to July 10, 2020, a total of 368 laboratory-confirmed COVID-19 cases reported in Xinfadi market, in which, 335 (91.03%) were symptomatic and 33 (8.97%) were asymptomatic. The cases were distributed in 11 districts, and most cases (252/368, 68.48%) were reported in Fengtai district. The incidence curve of the cases showed a typical outbreak pattern, the case number peaked on 13 June. The median age of the cases were 43 years (QR: 31-51). The asymptomatic cases (M=32, QR: 29-46) were younger than the symptomatic cases (M=43, QR: 31-52), the difference was significant (Z=2.416, P=0.016). The ratio of male to female was 1.26∶1. Most cases (236/368, 64.13%) were engaged in catering service and public place service. 73.91% (272/368) of the cases had historg of direct exposures in the Xinfadi market. 54.08%(199/368) of cases were detected through nucleic acid testing and screening. Mild and moderate cases accounted for 99.10% (332/335) and no death occurred. Conclusion: The COVID-19 cases in the outbreak in Xinfadi market were mainly engaged in catering service and public place service. The asymptomatic cases were younger than the symptomatic cases.