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1.
biorxiv; 2022.
Preprint in English | bioRxiv | ID: ppzbmed-10.1101.2022.10.07.511319

ABSTRACT

With the success of mRNA vaccines against coronavirus disease 2019 (COVID-19), strategies can now focus on improving vaccine potency, breadth, and stability. We present the design and preclinical evaluation of domain-based mRNA vaccines encoding the wild-type spike-protein receptor-binding (RBD) and/or N-terminal domains (NTD). An NTD-RBD linked candidate vaccine, mRNA-1283, showed improved antigen expression, antibody responses, and stability at refrigerated temperatures (2-8{degrees}C) compared with the clinically available mRNA-1273, which encodes the full-length spike protein. In mice administered mRNA-1283 as a primary series, booster, or variant-specific booster, similar or greater immune responses and protection from viral challenge were observed against wild-type, beta, delta, or omicron (BA.1) compared with mRNA-1273 immunized mice, especially at lower vaccine dosages. These results support clinical assessment of mRNA-1283 (NCT05137236).


Subject(s)
COVID-19
2.
biorxiv; 2022.
Preprint in English | bioRxiv | ID: ppzbmed-10.1101.2022.09.12.507614

ABSTRACT

The emergence of SARS-CoV-2 variants in the Omicron lineage with large number of substitutions in the spike protein that can evade antibody neutralization has resulted in diminished vaccine efficacy and persistent transmission. One strategy to broaden vaccine-induced immunity is to administer bivalent vaccines that encode for spike proteins from both historical and newly-emerged variant strains. Here, we evaluated the immunogenicity and protective efficacy of two bivalent vaccines that recently were authorized for use in Europe and the United States and contain two mRNAs encoding Wuhan-1 and either BA.1 (mRNA-1273.214) or BA.4/5 (mRNA-1273.222) spike proteins. As a primary immunization series in BALB/c mice, both bivalent vaccines induced broader neutralizing antibody responses than the constituent monovalent vaccines (mRNA-1273 [Wuhan-1], mRNA-1273.529 [BA.1], and mRNA-1273-045 [BA.4/5]). When administered to K18-hACE2 transgenic mice as a booster at 7 months after the primary vaccination series with mRNA-1273, the bivalent vaccines induced greater breadth and magnitude of neutralizing antibodies compared to an mRNA-1273 booster. Moreover, the response in bivalent vaccine-boosted mice was associated with increased protection against BA.5 infection and inflammation in the lung. Thus, boosting with bivalent Omicron-based mRNA-1273.214 or mRNA-1273.222 vaccines enhances immunogenicity and protection against currently circulating SARS-CoV-2 strains.


Subject(s)
Inflammation
3.
biorxiv; 2022.
Preprint in English | bioRxiv | ID: ppzbmed-10.1101.2022.04.12.488075

ABSTRACT

The Omicron BA.2 variant has become a dominant infective strain worldwide. Receptor binding studies reveal that the BA.2 spike trimer have 11-fold and 2-fold higher potency to human ACE2 than the spike trimer from the wildtype and Omicron BA.1 strains. The structure of the BA.2 spike timer reveals that all three receptor-binding domains (RBD) in the spike trimer are in open conformation, ready for high affinity binding to human ACE2, providing the basis for the increased infectivity of the BA.2 strain. JMB2002, a therapeutic antibody that was shown to have efficient inhibition of Omicron BA.1, also shows potent neutralization activities against Omicron BA.2. In addition, both BA.1 and BA.2 spike trimers are able to bind to the mouse ACE2 with high potency. In contrast, the wildtype spike trimer binds well to cat ACE2 but not to mouse ACE2. The structures of both BA.1 and BA.2 spike trimer bound to mouse ACE2 reveal the basis for their high affinity interactions. Together, these results suggest a possible evolution pathway for Omicron BA.1 and BA.2 variants from human-cat-mouse-human circle, which could have important implications in establishing an effective strategy in combating viral infection.


Subject(s)
Virus Diseases
4.
biorxiv; 2022.
Preprint in English | bioRxiv | ID: ppzbmed-10.1101.2022.02.07.479468

ABSTRACT

The emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in 2019 has led to the development of a large number of vaccines, several of which are now approved for use in humans. Understanding vaccine-elicited antibody responses against emerging SARS-CoV-2 variants of concern (VOC) in real time is key to inform public health policies. Serum neutralizing antibody titers are the current best correlate of protection from SARS-CoV-2 challenge in non-human primates and a key metric to understand immune evasion of VOC. We report that vaccinated BALB/c mice do not recapitulate faithfully the breadth and potency of neutralizing antibody responses against VOC, as compared to non-human primates or humans, suggesting caution should be exercised when interpreting data for this animal model.


Subject(s)
Coronavirus Infections
5.
biorxiv; 2022.
Preprint in English | bioRxiv | ID: ppzbmed-10.1101.2022.02.07.479419

ABSTRACT

The B.1.1.529 Omicron variant jeopardizes vaccines designed with early pandemic spike antigens. Here, we evaluated in mice the protective activity of the Moderna mRNA-1273 vaccine against B.1.1.529 before or after boosting with preclinical mRNA-1273 or mRNA-1273.529, an Omicron-matched vaccine. Whereas two doses of mRNA-1273 vaccine induced high levels of serum neutralizing antibodies against historical WA1/2020 strains, levels were lower against B.1.1.529 and associated with infection and inflammation in the lung. A primary vaccination series with mRNA-1273.529 potently neutralized B.1.1.529 but showed limited inhibition of historical or other SARS-CoV-2 variants. However, boosting with mRNA-1273 or mRNA-1273.529 vaccines increased serum neutralizing titers and protection against B.1.1.529 infection. Nonetheless, the levels of inhibitory antibodies were higher and viral burden and cytokines in the lung were slightly lower in mice given the Omicron-matched mRNA booster. Thus, in mice, boosting with mRNA-1273 or mRNA-1273.529 enhances protection against B.1.1.529 infection with limited differences in efficacy measured.


Subject(s)
Inflammation
6.
medrxiv; 2022.
Preprint in English | medRxiv | ID: ppzbmed-10.1101.2022.01.28.21268247

ABSTRACT

The emergence of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) B.1.1.529 (Omicron) variant has led to growing concerns of increased transmissibility and escape of both natural and vaccine-induced immunity. In this analysis, sera from adult participants in a phase 2 clinical study (NCT04405076) were tested for neutralizing activity against B.1.1.529 after a 2-dose (100 g) mRNA-1273 primary vaccination series and after a 50-g mRNA-1273 booster dose. Results from this preliminary analysis show that 1 month after completing the primary series, mRNA-1273-elicited serum neutralization of B.1.1.529 was below the lower limit of quantification; however, neutralization was observed at 2 weeks after the mRNA-1273 booster dose, although at a reduced level relative to wild-type SARS-CoV-2 (D614G) and lower than that observed against D614G at 1 month after the primary series.


Subject(s)
Coronavirus Infections
7.
biorxiv; 2021.
Preprint in English | bioRxiv | ID: ppzbmed-10.1101.2021.12.27.474273

ABSTRACT

The Omicron variant of SARS-CoV-2 has rapidly become the dominant infective strain and the focus efforts against the ongoing COVID-19 pandemic. Here we report an extensive set of structures of the Omicron spike trimer by its own or in complex with ACE2 and an anti-Omicron antibody. These structures reveal that most Omicron mutations are located on the surface of the spike protein, which confer stronger ACE2 binding by nearly 10 folds but become inactive epitopes resistant to many therapeutic antibodies. Importantly, both RBD and the closed conformation of the Omicron spike trimer are thermodynamically unstable, with the melting temperature of the Omicron RBD decreased by as much as 7°C, making the spiker trimer prone to random open conformations. An unusual RBD-RBD interaction in the ACE2-spike complex unique to Omicron is observed to support the open conformation and ACE2 binding, serving the basis for the higher infectivity of Omicron. A broad-spectrum therapeutic antibody JMB2002, which has completed Phase 1 clinical trial, is found to interact with the same two RBDs to inhibit ACE2 binding, in a mode that is distinguished from all previous antibodies, thus providing the structural basis for the potent inhibition of Omicron by this antibody. Together with biochemical data, our structures provide crucial insights into higher infectivity, antibody evasion and inhibition of Omicron.


Subject(s)
COVID-19
8.
researchsquare; 2021.
Preprint in English | PREPRINT-RESEARCHSQUARE | ID: ppzbmed-10.21203.rs.3.rs-1085392.v1

ABSTRACT

Purpose: This study aimed to explore the influences of online support of an Internet plus Shared Care diabetes management model on metabolic indicators and the differences before and after the coronavirus disease 2019 (COVID-19) pandemic. Method: Type 2 diabetes patients who visited the Peking University First Hospital Internet plus Shared Care clinic from May 18, 2020 to June 20, 2020 (after the COVID-19 pandemic subsided) were enrolled in the study. The age, gender, usage of insulin, and duration of diabetes of the patients were collected. The glycosylated hemoglobin (HbA1c), interval between two consecutive visits, communication frequencies with online diabetes educators through an app, online self-monitoring of blood glucose (SMBG) and upload count and SMBG pairing count (before–after meal) were collected before (prior to January 20, 2020) and after (from May 18, 2020 to June 20, 2020) the COVID-19 pandemic for logistic regression analysis. The R-3.4.4 and TWANG programs were used for analysis. The group of patients whose HbA1c did not change during the pandemic was the control group, while the group of patients with improved HbA1c was the dependent variable. Independent variables included age, gender, duration of disease, insulin usage, online communication amount, SMBG count, and SMBG pairing count. Propensity score matching (PSM) was applied with age, duration, gender, body mass index (BMI), HbA1c, low density lipoprotein- cholesterol (LDL-C), and blood pressure (BP) at baseline as the concomitant variable. After the PSM weighting, the average treatment effect (ATE) of post-pandemic BMI, HbA1c, LDL-C, and BP was compared with the baseline. Results: A total of 387 patients were enrolled in the study including 184 female (47.5%). The baseline values were the following: age, 61.7±9.4 year;, duration of diabetes, 11.7±8.2 years; BMI, 25.9±3.8Kg/m 2 ; HbA1c, 7.2±1.3%; LDL-C, 2.49±0.85mmol/L; systolic BP, 130.8±14.9 mmHg; and diastolic BP, 81.1±40.9 mmHg. Among variables, online communication amounted to a statistically significant contribution to the HbA1c improvement after the COVID-19 pandemic (OR=2.178, p=0.003). During the pandemic, each patient received 18 (3, 56) times online communication support per quarter. Patients were divided into four groups by quartiles: Q1 (more than 56 times/quarter, n=95), Q2 (18–56 times/quarter, n=97), Q3 (3–18 times/quarter, n=93), and Q4 (0–3 times/quarter, n=102). After PSM, post-pandemic data showed significant differences. Between-group variance was found in HbA1c (Q1 vs. Q3, -0.42±0.16%, p=0.009; Q1 vs. Q4, -0.53±0.15%, p=0.0009) and BMI (Q1 vs. Q3, -1.2±0.5, p=0.02; Q1 vs. Q4 -1.5±0.7, p=0.01) of patients. Conclusion: During the COVID-19 pandemic, high-quality online support of the Internet plus Shared Care diabetes management model can significantly improve the HbA1c and BMI of type 2 diabetes patients.


Subject(s)
Diabetes Mellitus, Type 2 , Diabetes Mellitus , Disease Models, Animal , Hypotension , COVID-19
9.
biorxiv; 2021.
Preprint in English | bioRxiv | ID: ppzbmed-10.1101.2021.08.11.456015

ABSTRACT

Neutralizing antibody responses gradually wane after vaccination with mRNA-1273 against several variants of concern (VOC), and additional boost vaccinations may be required to sustain immunity and protection. Here, we evaluated the immune responses in nonhuman primates that received 100 {micro}g of mRNA-1273 vaccine at 0 and 4 weeks and were boosted at week 29 with mRNA-1273 (homologous) or mRNA-1273.{beta} (heterologous), which encompasses the spike sequence of the B.1.351 (beta or {beta}) variant. Reciprocal ID50 pseudovirus neutralizing antibody geometric mean titers (GMT) against live SARS-CoV-2 D614G and the {beta} variant, were 4700 and 765, respectively, at week 6, the peak of primary response, and 644 and 553, respectively, at a 5-month post-vaccination memory time point. Two weeks following homologous or heterologous boost {beta}-specific reciprocal ID50 GMT were 5000 and 3000, respectively. At week 38, animals were challenged in the upper and lower airway with the {beta} variant. Two days post-challenge, viral replication was low to undetectable in both BAL and nasal swabs in most of the boosted animals. These data show that boosting with the homologous mRNA-1273 vaccine six months after primary immunization provides up to a 20-fold increase in neutralizing antibody responses across all VOC, which may be required to sustain high-level protection against severe disease, especially for at-risk populations. One-sentence summarymRNA-1273 boosted nonhuman primates have increased immune responses and are protected against SARS-CoV-2 beta infection.


Subject(s)
Severe Acute Respiratory Syndrome
10.
arxiv; 2021.
Preprint in English | PREPRINT-ARXIV | ID: ppzbmed-2108.01514v1

ABSTRACT

With the ongoing global pandemic of coronavirus disease 2019 (COVID-19), there is an increasing quest for more accessible, easy-to-use, rapid, inexpensive, and high accuracy diagnostic tools. Traditional disease diagnostic methods such as qRT-PCR (quantitative reverse transcription-PCR) and ELISA (enzyme-linked immunosorbent assay) require multiple steps, trained technicians, and long turnaround time that may worsen the disease surveillance and pandemic control. In sight of this situation, a rapid, one-step, easy-to-use, and high accuracy diagnostic platform will be valuable for future epidemic control especially for regions with scarce medical resources. Herein, we report a magnetic particle spectroscopy (MPS) platform for detection of SARS-CoV-2 biomarkers: spike and nucleocapsid proteins.


Subject(s)
COVID-19
11.
biorxiv; 2021.
Preprint in English | bioRxiv | ID: ppzbmed-10.1101.2021.06.28.449914

ABSTRACT

The emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants has led to growing concerns over increased transmissibility and the ability of some variants to partially escape immunity. Sera from participants immunized on a prime-boost schedule with the mRNA-1273 COVID-19 vaccine were tested for neutralizing activity against several SARS-CoV-2 variants, including variants of concern (VOCs) and variants of interest (VOIs), compared to neutralization of the wild-type SARS-CoV-2 virus (designated as D614G). Results showed minimal effects on neutralization titers against the B.1.1.7 (Alpha) variant (1.2-fold reduction compared with D614G); other VOCs such as B.1.351 (Beta, including B.1.351-v1, B.1.351-v2, and B.1.351-v3), B.1.617.2 (Delta), and P.1 (Gamma) showed decreased neutralization titers ranging from 2.1-fold to 8.4-fold reductions compared with D614G, although all remained susceptible to mRNA-1273-elicited serum neutralization.


Subject(s)
Coronavirus Infections , COVID-19
12.
biorxiv; 2021.
Preprint in English | bioRxiv | ID: ppzbmed-10.1101.2021.05.21.445189

ABSTRACT

Background: Vaccine efficacy against the B.1.351 variant following mRNA-1273 vaccination in humans has not been determined. Nonhuman primates (NHP) are a useful model for demonstrating whether mRNA-1273 mediates protection against B.1.351. Methods: Nonhuman primates received 30 or 100 microgram of mRNA-1273 as a prime-boost vaccine at 0 and 4 weeks, a single immunization of 30 microgram at week 0, or no vaccine. Antibody and T cell responses were assessed in blood, bronchioalveolar lavages (BAL), and nasal washes. Viral replication in BAL and nasal swabs were determined by qRT-PCR for sgRNA, and histopathology and viral antigen quantification were performed on lung tissue post-challenge. Results: Eight weeks post-boost, 100 microgram x2 of mRNA-1273 induced reciprocal ID50 neutralizing geometric mean titers against live SARS-CoV-2 D614G and B.1.351 of 3300 and 240, respectively, and 430 and 84 for the 30 microgram x2 group. There were no detectable neutralizing antibodies against B.1351 after the single immunization of 30 microgram. On day 2 following B.1.351 challenge, sgRNA in BAL was undetectable in 6 of 8 NHP that received 100 microgram x2 of mRNA-1273, and there was a ~2-log reduction in sgRNA in NHP that received two doses of 30 microgram compared to controls. In nasal swabs, there was a 1-log10 reduction observed in the 100 microgram x2 group. There was limited inflammation or viral antigen in lungs of vaccinated NHP post-challenge. Conclusions: Immunization with two doses of mRNA-1273 achieves effective immunity that rapidly controls lower and upper airway viral replication against the B.1.351 variant in NHP.


Subject(s)
Inflammation
13.
medrxiv; 2021.
Preprint in English | medRxiv | ID: ppzbmed-10.1101.2021.05.05.21256716

ABSTRACT

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the causative agent of a global pandemic of coronavirus disease 2019 (COVID-19) that has led to more than 3 million deaths worldwide. Safe and effective vaccines are now available, including the mRNA-1273 prototype vaccine, which encodes for the Wuhan SARS-CoV-2 Spike protein stabilized in the prefusion conformation by 2 proline substitutions. This vaccine showed 94% efficacy in prevention of symptomatic COVID-19 disease in a phase 3 clinical study. Recently, SARS-CoV-2 variants have emerged, some of which have shown decreased susceptibility to neutralization by vaccine-induced antibody, most notably the B.1.351 variant, although the overall impact on vaccine efficacy remains to be determined. In addition, recent evidence of waning antibody levels after infection or vaccination point to the need for periodic boosting of immunity. Here we present the preliminary evaluation of a clinical study on the use of the prototype mRNA-1273 or modified COVID-19 mRNA vaccines, designed to target emerging SARS-CoV-2 variants as booster vaccines in participants previously vaccinated approximately 6 months earlier with two doses of the prototype vaccine, mRNA-1273. The modified vaccines include a monovalent mRNA-1273.351 encoding for the S protein found in the B.1.351 variant and multivalent mRNA-1273.211 comprising a 1:1 mix of mRNA-1273 and mRNA-1273.351. As single 50 g booster vaccinations, both mRNA-1273 and mRNA-1273.351 had acceptable safety profiles and were immunogenic. Antibody neutralization titers against B.1.351 and P.1 variants measured by SARS-CoV-2 pseudovirus neutralization (PsVN) assays before the booster vaccinations, approximately 6 to 8 months after the primary series, were low or below the assay limit of quantification, although GMTs versus the wild-type strain remained above levels likely to be protective. Two weeks after the booster vaccinations, titers against the wild-type original strain, B.1.351, and P.1 variants increased to levels similar to or higher than peak titers after the primary series vaccinations. Although both mRNA-1273 and mRNA-1273.351 boosted neutralization of the wild-type original strain, and B.1.351 and P.1 variants, mRNA-1273.351 appeared to be more effective at increasing neutralization of the B.1.351 virus versus a boost with mRNA-1273. The vaccine trial is ongoing and boosting of clinical trial participants with the multivalent mRNA-1273.211 is currently being evaluated.


Subject(s)
Severe Acute Respiratory Syndrome , COVID-19
14.
biorxiv; 2021.
Preprint in English | bioRxiv | ID: ppzbmed-10.1101.2021.04.20.440647

ABSTRACT

Immune correlates of protection can be used as surrogate endpoints for vaccine efficacy. The nonhuman primate (NHP) model of SARS-CoV-2 infection replicates key features of human infection and may be used to define immune correlates of protection following vaccination. Here, NHP received either no vaccine or doses ranging from 0.3-100 micrograms of mRNA-1273, a mRNA vaccine encoding the prefusion-stabilized SARS-CoV-2 spike (S-2P) protein encapsulated in a lipid nanoparticle. mRNA-1273 vaccination elicited robust circulating and mucosal antibody responses in a dose-dependent manner. Viral replication was significantly reduced in bronchoalveolar lavages and nasal swabs following SARS-CoV-2 challenge in vaccinated animals and was most strongly correlated with levels of anti-S antibody binding and neutralizing activity. Consistent with antibodies being a correlate of protection, passive transfer of vaccine-induced IgG to naive hamsters was sufficient to mediate protection. Taken together, these data show that mRNA-1273 vaccine-induced humoral immune responses are a mechanistic correlate of protection against SARS-CoV-2 infection in NHP.


Subject(s)
COVID-19
15.
biorxiv; 2021.
Preprint in English | bioRxiv | ID: ppzbmed-10.1101.2021.04.13.439482

ABSTRACT

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the causative agent of a global pandemic that has led to more than 2.8 million deaths worldwide. Safe and effective vaccines are now available, including Moderna's COVID-19 vaccine (mRNA-1273) that showed 94% efficacy in prevention of symptomatic COVID-19 disease in a phase 3 clinical study. mRNA-1273 encodes for a prefusion stabilized full length spike (S) protein of the Wuhan-Hu-1 isolate. However, the emergence of SARS-CoV-2 variants has led to concerns of viral escape from vaccine-induced immunity. Several emerging variants have shown decreased susceptibility to neutralization by vaccine induced immunity, most notably the B.1.351 variant, although the overall impact on vaccine efficacy remains to be determined. Here, we present the initial evaluation in mice of two updated COVID-19 mRNA vaccines designed to target emerging SARS-CoV-2 variants: (1) monovalent mRNA-1273.351 encodes for the S protein found in the B.1.351 lineage and (2) mRNA-1273.211 comprising a 1:1 mix of mRNA-1273 and mRNA-1273.351. Both vaccines were evaluated as a 2-dose primary series in mice; mRNA-1273.351 was also evaluated as a booster dose in animals previously vaccinated with 2-doses of mRNA-1273. The results demonstrated that a primary vaccination series of mRNA-1273.351 was effective at increasing neutralizing antibody titers against the B.1.351 lineage, while mRNA-1273.211 was most effective at providing broad cross-variant neutralization in mice. In addition, these results demonstrated a third dose of mRNA-1273.351 significantly increased both wild-type and B.1.351-specific neutralization titers. Both mRNA-1273.351 and mRNA-1273.211 are currently being evaluated in additional pre-clinical challenge models and in phase 1/2 clinical studies.


Subject(s)
COVID-19 , Severe Acute Respiratory Syndrome
16.
arxiv; 2020.
Preprint in English | PREPRINT-ARXIV | ID: ppzbmed-2011.10211v1

ABSTRACT

Nowadays, there is an increasing demand for more accessible routine diagnostics for patients with respect to high accuracy, ease of use, and low cost. However, the quantitative and high accuracy bioassays in large hospitals and laboratories usually require trained technicians and equipment that is both bulky and expensive. In addition, the multi-step bioassays and long turnaround time could severely affect the disease surveillance and control especially in pandemics such as influenza and COVID-19. In view of this, a portable, quantitative bioassay device will be valuable in regions with scarce medical resources and help relieve burden on local healthcare systems. Herein, we introduce the MagiCoil diagnostic device, an inexpensive, portable, quantitative and rapid bioassay platform based on magnetic particle spectrometer (MPS) technique. MPS detects the dynamic magnetic responses of magnetic nanoparticles (MNPs) and uses the harmonics from oscillating MNPs as metrics for sensitive and quantitative bioassays. This device does not require trained technicians to operate and employs a fully automatic, one-step, wash-free assay with user friendly smartphone interface. Using a streptavidin-biotin binding system as a model, we show that the detection limit of the current portable device for streptavidin is 64 nM (equal to 5.12 pmole). In addition, this MPS technique is very versatile and allows for the detection of different diseases just by changing the surface modifications on MNPs.


Subject(s)
COVID-19
17.
arxiv; 2020.
Preprint in English | PREPRINT-ARXIV | ID: ppzbmed-2007.04809v1

ABSTRACT

The novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which causes coronavirus disease 2019 (COVID-19), is a threat to the global healthcare system and economic security. As of July 2020, no specific drugs or vaccines are yet available for COVID-19, fast and accurate diagnosis for SARS-CoV-2 is essential in slowing down the spread of COVID-19 and for efficient implementation of control and containment strategies. Magnetic immunoassay is a novel and emerging topic representing the frontiers of current biosensing and magnetics areas. The past decade has seen rapid growth in applying magnetic tools for biological and biomedical applications. Recent advances in magnetic materials and nanotechnologies have transformed current diagnostic methods to nanoscale and pushed the detection limit to early stage disease diagnosis. Herein, this review covers the literatures of magnetic immunoassay platforms for virus and pathogen detections, before COVID-19. We reviewed the popular magnetic immunoassay platforms including magnetoresistance (MR) sensors, magnetic particle spectroscopy (MPS), and nuclear magnetic resonance (NMR). Magnetic Point-of-Care (POC) diagnostic kits are also reviewed aiming at developing plug-and-play diagnostics to manage the SARS-CoV-2 outbreak as well as preventing future epidemics. In addition, other platforms that use magnetic materials as auxiliary tools for enhanced pathogen and virus detections are also covered. The goal of this review is to inform the researchers of diagnostic and surveillance platforms for SARS-CoV-2 and their performances.


Subject(s)
COVID-19
18.
researchsquare; 2020.
Preprint in English | PREPRINT-RESEARCHSQUARE | ID: ppzbmed-10.21203.rs.3.rs-36225.v1

ABSTRACT

Background At the end of 2019, the Coronavirus disease 2019 (COVID-19), with highly infectious, transmits rapidly. So it has caused people panic to a certain degree. Methods This cross-sectional study performed via an online survey run from January 30 to March 30, 2020. 1144 people in South China (287 of level 1 population, 121 of level 2 population, 160 of level 3 population, 576 of level 4 population ) were investigated. GAD-7 scale, PHQ-9 scale, and PSS-10 scale were used to evaluate the mental health status of different populations. Results Among 1144 subjects, the average GAD-7 score was 4(1,8), the average PHQ-9 score was 4(1,9), and the average PSS-10 score was 16(11,19). There were statistically significant differences in the scores of GAD-7 (H = 15.235, P <0.01), PHQ-9 (H = 9.265, P = 0.026), and PSS-10 (H = 8.435, P = 0.049) among different levels of population. In the score of GAD-7: The anxiety degree of the level 1 population is higher than that of the level 2 population and the level 4 population. The difference between the two pairs is statistically significant (Z = -2.932, -4.012, -2.949, P <0.005). There are significant differences in items of“becoming easily annoyed or irritable”, "seemingly terrible things will happen"(Z = -3.399 ~ -2.055, P <0.005); Score of PHQ-9: The depression degree of the level 1 population and the level 2 population is higher than that of the level 4 population, and the difference between the two pairs is statistically significant (Z = -3.38, -2.682, P <0.005). There are significant differences in items of "difficult to fall asleep or not awake", "feeling depressed" and other related items (Z = -2.885 ~ -2.003, P <0.005); Score of PSS-10: The stress degree of the level 3 population is higher than that of the level 1 population and the level 4 population (Z = -3.693 ~ -2.702, P <0.005). There are significant differences in items of "feel confident", "life are as expected", "the ability to control anger", "the things are all under control" and other related items (Z = -4.782 ~ -2.102, P <0.005). Conclusion There are differences in the effects of COVID-19 on the mental health of people with different identities. Appropriate psychological interventions should be provided for different populations in combination with their mental health status.


Subject(s)
COVID-19 , Anxiety Disorders , Depressive Disorder
19.
researchsquare; 2020.
Preprint in English | PREPRINT-RESEARCHSQUARE | ID: ppzbmed-10.21203.rs.3.rs-33073.v1

ABSTRACT

Background:The 2019 novel coronavirus disease (COVID-19) spread in many countries.Data about viral shedding duration, particularly the prolonged ones of the pathogen SARS-Coronavirus-2 (SARS-CoV-2) is scarce. The longest viral RNA sheddingduration reported previously was 37 days. Herein, we report the clinical and immunologic features ofrecovered COVID-19cases with a medium viral RNA shedding duration of 44 days. Cases presentation: Nine laboratory-confirmed COVID-19 cases from Wuhan with viral RNA shedding duration more than 30 days were included in our study,5 of them were moderate.Althoughinflammatory markers were significantlyhigher, the medium duration in severepatients was similar to that in moderate patients (44.5days vs. 43.6days). Severepatients showed higher NK cells levels, although the T cells and B cells were lower as compared with moderate patients. Contrary to previous reports in influenza, prolonged viralshedding time did not cause poor prognosis in this study.Conclusions: There could be characteristic immunological dysfunction in COVID-19 patients with prolonged viral shedding durationand interestingly, prolonged viral shedding duration seemed not to be related with poor prognosis.


Subject(s)
COVID-19 , Immune System Diseases
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