Electrospray-on-Electrospun Breathable, Biodegradable, and Robust Nanofibrous Membranes with Photocatalytic Bactericidal Activity

The increasing emergence of infectious diseases like COVID-19 has created an urgent need for filtration/purification materials coupled with multifunctional features such as mechanical integrity, excellent airflow/filtration, and antibacterial/antimicrobial properties. Polymer membranes and metal-organic frameworks (MOFs) have demonstrated high effectiveness in air filtration and purification. MOF nanoparticles have been introduced into electrospun polymer nanofibrous membranes through embedding or postsolution growth. However, the derived hybrids are still facing the issue of (1) limited MOF exposure, which leads to low efficacy;and (2) uncontrollable growth, which leads to pore blocking and low breathability. In this work, we customized an electrospray-on-electrospinning in situ process to dynamically integrate MOF nanoparticles into a robust and elastic continuous nanofibrous membrane for advanced properties including high mechanical strength and flexibility, excellent breathability, particle filtration, and good antimicrobial performance. Biodegradable polylactic acid was reinforced by the poly(hydroxybutyrate)-di-poly(DLA-CL)x copolymer (PHBR) and used as an electrospinning matrix, while MOF nanoparticles were simultaneously electrically sprayed onto the nanofibers with easily controllable MOF loading. The MOF nanoparticles were homogeneously deposited onto nanofibers without clogging the pores in the membrane. The collision of PLA and MOF under the wet status during electrospinning and the hydrogen bonding through C=O and N-H bonds strengthen the affinity between PLA nanofibers and MOF nanoparticles. Because of these factors, the MOF-incorporated PLA/PHBR nanofibrous membrane achieved over 95% particle filtration efficiency with enhanced mechanical properties while maintaining high breathability. Meanwhile, it exhibits excellent photocatalytic antibacterial performance, which is necessary to kill microbes. The electrospray-on-electrospinning in situ process provides an efficient and straightforward way to hybridize one-dimensional (1D) or two-dimensional (2D) nanomaterials into a continuous nanofibrous membrane with strong interaction and controllable loading. Upon integrating proper functionalities from the materials, the obtained hybrids are able to achieve multifunctionalities for various applications.

A discrete state-structured model on networks with two transmission modes: Global dynamics analysis

In this paper, we formulate and analyze a class of discrete state structured epidemic models that spread through both horizontal and vertical transmissions on networks, where infected individuals can move from one infected state to any other state so that our models include all possible state transfers (disease deterioration and amelioration) among different states. Many epidemic transmissions with or without vertical transmission in nature can be analyzed by referring to our models, such as HIV-1, viral hepatitis, and Covid19. We derive the basic reproduction number R0= Rh+ Rv, and prove that the global dynamics are completely determined by the basic reproduction number: if R0 <= 1, the disease-free equilibrium is globally asymptotically stable and the disease always dies out;if R0 > 1, the disease-free equilibrium is unstable, and there exists a unique endemic equilibrium that is globally asymptotically stable, and the disease persists at a positive level in the population. It also implies that vertical transmission has an impact on maintaining infectious diseases when horizontal transmission cannot sustain the disease on its own. The proof of global stability is based on the graph-theoretic approach and answer the open problem left in [1]. Finally, numerical simulations are performed to illustrate the theoretical results.

Neutralizing Antibody Response to SARS-CoV-2 Vaccination in Multiple Sclerosis

Objective: To investigate the humoral immune response following SARS-CoV-2 vaccination in patients with multiple sclerosis (pwMS) and to determine the effect of disease modifying therapies (DMT) on the vaccination response. Background: Coronavirus disease 19 (COVD-19), a highly transmissible and potentially fatal illness caused by SARS-CoV-2, emerged as a global pandemic in early 2020. Several vaccines, including 2 innovative mRNA vaccines, were developed against this virus. To reduce relapse rates and slow disability accumulation, pwMS are often treated with DMTs which have anti-inflammatory properties and regulate adaptive immunity. An important clinical issue concerns the impact of DMTs on the efficacy of SARS-CoV-2 vaccination, and the eventual need for booster doses. In this study, we measured the titers of anti-SARS-CoV-2 neutralizing antibodies (nAbs) in pwMS following SARS-CoV-2 vaccination. Design/Methods: We conducted a prospective longitudinal study in pwMS at the Ohio State University (OSU) MS Center. Longitudinal serum samples were obtained from pwMS prior to and after the administration of the SARS-CoV-2 vaccine. These samples were analyzed for nAbs against SARS-CoV-2 spike protein using a novel pseudotyped-lentivirus-based virus neutralization assay. OSU health care workers (HCWs) served as healthy controls. Results: Of eighty-three consented subjects, fifty-two had post vaccination serum samples analyzed. Although pwMS did not exhibit drastically different nAb titers compared to HCWs, 21% (n=11) did not have detectable nAb titers post-vaccination (NT50 < 40)-including 9 patients on B-cell depleting therapies, 1 on sphingosine 1-phosphate modulator, and 1 on no DMT. Compared to patients not on DMT, pwMS on B-cell depleting therapies exhibited 7-fold lower nAb titers, while those on fumarates or beta-interferon exhibited no significant difference to patients not on DMT. Conclusions: Humoral immune response to the SARS-CoV-2 vaccine may be attenuated by certain DMTs, most notably B-cell depleting drugs. Further studies are underway to determine the effect of booster vaccine on nAb levels.

Expressions of SAA, CRP, and FERR in different severities of COVID-19.

OBJECTIVE: To explore the expression and significance of SAA, CRP and FERR in patients diagnosed with COVID-19. PATIENTS AND METHODS: A total of 225 patients diagnosed with COVID-19 who were admitted to the North Hospital of First Hospital in Changsha, China, from 9th February 2020 to 7th March 2020 were enrolled. Their general data, laboratory test results and levels of SAA, CRP and FERR were extracted from electronic medical records. RESULTS: Age was an important risk factor for the severity of COVID-19 in the patients. Compared with the non-severe group, the severe group showed statistical significance in the levels of total protein, albumin, ALT and AST in liver function, UA in renal function, myocardial enzyme CK-MB and LDH, and immunoglobulin IgG and IgM. The levels of SAA, CRP, and FERR were significantly increased in patients with severe COVID-19. ROC curve analysis results showed that the AUC, from small to large, was as follows: SAA+CRP+FERR, CRP + FERR, SAA + CRP, SAA + FERR, SAA, FERR, and CRP, which indicated the benefit of the combination of the three indicators. The sensitivity and specificity of the combined detection of the three indicators were higher than those of the detection of any single indicator or two combined indicators. A Spearman correlation analysis of the data showed that the initial CRP/SAA, SAA/FERR, and CRP/FERR were positively correlated. The continuous results of SAA, CRP and FERR throughout the study period showed that the values of the severe group on a given day were higher than those of the non-severe group; the values of the two groups peaked on the 5th or 7th day and then decreased, and the decreasing trend of the severe group was more evident. CONCLUSIONS: SAA, CRP and FERR are sensitive serological indicators used to evaluate the severity of COVID-19. The combined detection of serum SAA, FERR, and CRP, which are positively related to COVID-19 infection, offers guiding significance for the occurrence of COVID-19 infection and the severity of the disease. Such detection provides effective detection indicators for the progress and prognosis of COVID-19; these indicators will enable effective intervention measures to be implemented in time and the rates of severe illness and mortality to be reduced.

[Epidemiological characteristics of COVID-19 family clustering in Zhejiang Province].

Objective: To investigate the epidemiological characteristics for family clusters of COVID-19 in Zhejiang Province. Methods: The data including cases information of asymptomatic infected cases of family clusters of COVID-19 in Zhejiang Province were collected from Public Health Emergencies Reporting System of China Center for Disease Control and Prevention. Calculate the case number of subsequent cases, index cases, asymptomatic infected cases, exposure cases, and then, compute family secondary attack rate (SIR) and serial interval. Results: A total of 389 cases comprised 149 family index cases and 240 subsequent cases. The clinical symptoms between family index cases and subsequent cases (exclude asymptomatic infected cases ) were similar, fever was the most common symptoms in the two groups 115 (77.18%) and 110（48.67%）respectively, the cases with diarrhea symptoms accounted for the least proportion, which were 7 (4.70%) and 6 (2.65%) respectively. The serial interval between the family index cases and the subsequent cases [M (P25, P75)] was 4.00 (2.00, 6.00) days. Family secondary attack rate for subsequent cases was 34.43%, subsequent cases aged between 14 and 60 have the highest SIR (43.42%) compared with other two age groups, the difference was statistically (P<0.001); the family SIR of the spouses of the family index cases is 68.57%, and are higher than that of parents (29.03%), children (25.00%) and other family members (24.21%), the difference was also statistically (P<0.001). Conclusion: 2019 novel coronavirus has shorter serial interval and higher family SIR, the SIR of spouses is higher than other family members.