Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 20
Filter
Add more filters










Publication year range
1.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-993716

ABSTRACT

COVID-19 is caused by a novel coronavirus-severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2), which has being spreading around the world, posing a serious threat to human health and lives. Neutralizing antibodies and small molecule inhibitors for virus replication cycle are the main antiviral treatment for novel coronavirus recommended in China. To further promote the rational use of antiviral therapy in clinical practice, the National Center for Infectious Diseases (Beijing Ditan Hospital Capital Medical University and the First Affiliated Hospital, Zhejiang University School of Medicine) invited experts in fields of infectious diseases, respiratory and intensive care to develop an Expert Consensus on Antiviral Therapy of COVID-19 based on the Diagnosis and Treatment Guideline for COVID-19 ( trial version 10) and experiences in the diagnosis and treatment of COVID-19 in China. The consensus is concise, practical and highly operable, hopefully it would improve the understanding of antiviral therapy for clinicians and provide suggestions for standardized medication in treatment of COVID-19.

2.
Preprint in English | bioRxiv | ID: ppbiorxiv-507787

ABSTRACT

Continuous evolution of Omicron has led to a rapid and simultaneous emergence of numerous variants that display growth advantages over BA. 5. Despite their divergent evolutionary courses, mutations on their receptor-binding domain (RBD) converge on several hotspots. The driving force and destination of such convergent evolution and its impact on humoral immunity remain unclear. Here, we demonstrate that these convergent mutations can cause striking evasion of neutralizing antibody (NAb) drugs and convalescent plasma, including those from BA.5 breakthrough infection, while maintaining sufficient ACE2 binding capability. BQ.1.1.10, BA.4.6.3, XBB, and CH. 1.1 are the most antibody-evasive strain tested, even exceeding SARS-CoV-1 level. To delineate the origin of the convergent evolution, we determined the escape mutation profiles and neutralization activity of monoclonal antibodies (mAbs) isolated from BA.2 and BA.5 breakthrough-infection convalescents. Importantly, due to humoral immune imprinting, BA.2 and especially BA.5 breakthrough infection caused significant reductions in the epitope diversity of NAbs and increased proportion of non-neutralizing mAbs, which in turn concentrated humoral immune pressure and promoted convergent evolution. Moreover, we showed that the convergent RBD mutations could be accurately inferred by integrated deep mutational scanning (DMS) profiles, and the evolution trends of BA.2.75/BA.5 subvariants could be well-simulated through constructed convergent pseudovirus mutants. Together, our results suggest current herd immunity and BA.5 vaccine boosters may not provide good protection against infection. Broad-spectrum SARS-CoV-2 vaccines and NAb drugs development should be highly prioritized, and the constructed mutants could help to examine their effectiveness in advance.

3.
Preprint in English | bioRxiv | ID: ppbiorxiv-503384

ABSTRACT

Multiple BA.4 and BA.5 subvariants with R346 mutations on the spike glycoprotein have been identified in various countries, such as BA.4.6/BF.7 harboring R346T, BA.4.7 harboring R346S, and BA.5.9 harboring R346I. These subvariants, especially BA.4.6, exhibit substantial growth advantages compared to BA.4/BA.5. In this study, we showed that BA.4.6, BA.4.7, and BA.5.9 displayed higher humoral immunity evasion capability than BA.4/BA.5, causing 1.5 to 1.9-fold decrease in NT50 of the plasma from BA.1 and BA.2 breakthrough-infection convalescents compared to BA.4/BA.5. Importantly, plasma from BA.5 breakthrough-infection convalescents also exhibits significant neutralization activity decrease against BA.4.6, BA.4.7, and BA.5.9 than BA.4/BA.5, showing on average 2.4 to 2.6-fold decrease in NT50. For neutralizing antibody drugs, Bebtelovimab remains potent, while Evusheld is completely escaped by these subvariants. Together, our results rationalize the prevailing advantages of the R346 mutated BA.4/BA.5 subvariants and urge the close monitoring of these mutants, which could lead to the next wave of the pandemic.

4.
Preprint in English | bioRxiv | ID: ppbiorxiv-499114

ABSTRACT

SARS-CoV-2 Omicron sublineages have escaped most RBD-targeting therapeutic neutralizing antibodies (NAbs), which proves the previous NAb drug screening strategies deficient against the fast-evolving SARS-CoV-2. Better broad NAb drug candidate selection methods are needed. Here, we describe a rational approach for identifying RBD-targeting broad SARS-CoV-2 NAb cocktails. Based on high-throughput epitope determination, we propose that broad NAb drugs should target non-immunodominant RBD epitopes to avoid herd immunity-directed escape mutations. Also, their interacting antigen residues should focus on sarbecovirus conserved sites and associate with critical viral functions, making the antibody-escaping mutations less likely to appear. Following the criteria, a featured non-competing antibody cocktail, SA55+SA58, is identified from a large collection of broad sarbecovirus NAbs isolated from SARS convalescents. SA55+SA58 potently neutralizes ACE2-utilizing sarbecoviruses, including circulating Omicron variants, and could serve as broad SARS-CoV-2 prophylactics to offer long-term protection. Our screening strategy can also be applied to identify broad-spectrum NAb drugs against other fast-evolving viruses, such as influenza viruses.

5.
Preprint in English | bioRxiv | ID: ppbiorxiv-500332

ABSTRACT

Recently emerged SARS-CoV-2 Omicron subvariant, BA.2.75, displayed a local growth advantage over BA.2.38, BA.2.76 and BA.5 in India. The underlying mechanism of BA.2.75s enhanced infectivity, especially compared to BA.5, remains unclear. Here, we show that BA.2.75 exhibits substantially higher ACE2-binding affinity than BA.5. Also, BA.2.75 spike shows decreased thermostability and increased "up" RBD conformation in acidic conditions, suggesting enhanced low-pH-endosomal cell-entry pathway utilization. BA.2.75 is less humoral immune evasive than BA.4/BA.5 in BA.1/BA.2 breakthrough-infection convalescents; however, BA.2.75 shows heavier neutralization evasion in Delta breakthrough-infection convalescents. Importantly, plasma from BA.5 breakthrough infection exhibit significantly weaker neutralization against BA.2.75 than BA.5, mainly due to BA.2.75s distinct RBD and NTD-targeting antibody escaping pattern from BA.4/BA.5. Additionally, Evusheld and Bebtelovimab remain effective against BA.2.75, and Sotrovimab recovered RBD-binding affinity. Together, our results suggest BA.2.75 may prevail after the global BA.4/BA.5 wave, and its increased receptor-binding capability could allow further incorporation of immune-evasive mutations.

6.
Preprint in English | bioRxiv | ID: ppbiorxiv-492903

ABSTRACT

Recent studies found that Omicron variant escapes vaccine-elicited immunity. Interestingly, potent cross-clade pan-sarbecovirus neutralizing antibodies were found in survivors of the infection by SARS-CoV-1 after BNT162b2 mRNA vaccination (N Engl J Med. 2021 Oct 7;385(15):1401-1406). These pan-sarbecovirus neutralizing antibodies were observed to efficiently neutralize the infection driven by the S protein from both SARS-CoV and multiple SARS-CoV-2 variants of concern (VOC) including B.1.1.7 (Alpha), B.1.351 (Beta), and B.1.617.2 (Delta). However, whether these cross-reactive antibodies could neutralize the Omicron variant is still unknown. Based on the data collected from a cohort of SARS-CoV-1 survivors received 3-dose of immunization, our studies reported herein showed that a high level of neutralizing antibodies against both SARS-CoV-1 and SARS-CoV-2 were elicited by a 3rd-dose of booster vaccination of protein subunit vaccine ZF2001. However, a dramatically reduced neutralization of SARS-CoV-2 Omicron Variant (B.1.1.529) is observed in sera from these SARS-CoV-1 survivors received 3-dose of Vaccination. Our results indicates that the rapid development of pan-variant adapted vaccines is warranted.

7.
Preprint in English | bioRxiv | ID: ppbiorxiv-489997

ABSTRACT

SARS-CoV-2 Omicron sublineages BA.2.12.1, BA.4 and BA.5 exhibit higher transmissibility over BA.21. The new variants receptor binding and immune evasion capability require immediate investigation. Here, coupled with Spike structural comparisons, we show that BA.2.12.1 and BA.4/BA.5 exhibit comparable ACE2-binding affinities to BA.2. Importantly, BA.2.12.1 and BA.4/BA.5 display stronger neutralization evasion than BA.2 against the plasma from 3-dose vaccination and, most strikingly, from post-vaccination BA.1 infections. To delineate the underlying antibody evasion mechanism, we determined the escaping mutation profiles2, epitope distribution3 and Omicron neutralization efficacy of 1640 RBD-directed neutralizing antibodies (NAbs), including 614 isolated from BA.1 convalescents. Interestingly, post-vaccination BA.1 infection mainly recalls wildtype-induced humoral memory. The resulting elicited antibodies could neutralize both wildtype and BA.1 and are enriched on non-ACE2-competing epitopes. However, most of these cross-reactive NAbs are heavily escaped by L452Q, L452R and F486V. BA.1 infection can also induce new clones of BA.1-specific antibodies that potently neutralize BA.1; nevertheless, these NAbs are largely escaped by BA.2/BA.4/BA.5 due to D405N and F486V, and react weakly to pre-Omicron variants, exhibiting poor neutralization breadths. As for therapeutic NAbs, Bebtelovimab4 and Cilgavimab5 can effectively neutralize BA.2.12.1 and BA.4/BA.5, while the S371F, D405N and R408S mutations would undermine most broad sarbecovirus NAbs. Together, our results indicate that Omicron may evolve mutations to evade the humoral immunity elicited by BA.1 infection, suggesting that BA.1-derived vaccine boosters may not achieve broad-spectrum protection against new Omicron variants.

8.
Preprint in English | bioRxiv | ID: ppbiorxiv-479349

ABSTRACT

Omicron sub-lineage BA.2 has rapidly surged globally, accounting for over 60% of recent SARS-CoV-2 infections. Newly acquired RBD mutations and high transmission advantage over BA.1 urge the investigation of BA.2s immune evasion capability. Here, we show that BA.2 causes strong neutralization resistance, comparable to BA.1, in vaccinated individuals plasma. However, BA.2 displays more severe antibody evasion in BA.1 convalescents, and most prominently, in vaccinated SARS convalescents plasma, suggesting a substantial antigenicity difference between BA.2 and BA.1. To specify, we determined the escaping mutation profiles1,2 of 714 SARS-CoV-2 RBD neutralizing antibodies, including 241 broad sarbecovirus neutralizing antibodies isolated from SARS convalescents, and measured their neutralization efficacy against BA.1, BA.1.1, BA.2. Importantly, BA.2 specifically induces large-scale escape of BA.1/BA.1.1-effective broad sarbecovirus neutralizing antibodies via novel mutations T376A, D405N, and R408S. These sites were highly conserved across sarbecoviruses, suggesting that Omicron BA.2 arose from immune pressure selection instead of zoonotic spillover. Moreover, BA.2 reduces the efficacy of S309 (Sotrovimab)3,4 and broad sarbecovirus neutralizing antibodies targeting the similar epitope region, including BD55-5840. Structural comparisons of BD55-5840 in complexes with BA.1 and BA.2 spike suggest that BA.2 could hinder antibody binding through S371F-induced N343-glycan displacement. Intriguingly, the absence of G446S mutation in BA.2 enabled a proportion of 440-449 linear epitope targeting antibodies to retain neutralizing efficacy, including COV2-2130 (Cilgavimab)5. Together, we showed that BA.2 exhibits distinct antigenicity compared to BA.1 and provided a comprehensive profile of SARS-CoV-2 antibody escaping mutations. Our study offers critical insights into the humoral immune evading mechanism of current and future variants.

9.
Preprint in English | bioRxiv | ID: ppbiorxiv-476850

ABSTRACT

Since the first report on November 24, 2021, the Omicron SARS-CoV-2 variant is now overwhelmingly spreading across the world. Two SARS-CoV-2 inactivated vaccines (IAVs), one recombinant protein subunit vaccine (PRV), and one adenovirus-vectored vaccine (AdV) have been widely administrated in many countries including China to pursue herd immunity. Here we investigated cross-neutralizing activities in 341 human serum specimens elicited by full-course vaccinations with IAV, PRV and AdV, and by various vaccine boosters following prime IAV and AdV vaccinations. We found that all types of vaccines induced significantly lower neutralizing antibody titers against the Omicron variant than against the prototype strain. For prime vaccinations with IAV and AdV, heterologous boosters with AdV and PRV, respectively, elevated serum Omicron-neutralizing activities to the highest degrees. In a mouse model, we further demonstrated that among a series of variant-derived RBD-encoding mRNA vaccine boosters, it is only the Omicron booster that significantly enhanced Omicron neutralizing antibody titers compared with the prototype booster following a prime immunization with a prototype S-encoding mRNA vaccine candidate. In summary, our systematical investigations of various vaccine boosters inform potential booster administrations in the future to combat the Omicron variant.

10.
Preprint in English | bioRxiv | ID: ppbiorxiv-470392

ABSTRACT

The SARS-CoV-2 B.1.1.529 variant (Omicron) contains 15 mutations on the receptor-binding domain (RBD). How Omicron would evade RBD neutralizing antibodies (NAbs) requires immediate investigation. Here, we used high-throughput yeast display screening1,2 to determine the RBD escaping mutation profiles for 247 human anti-RBD NAbs and showed that the NAbs could be unsupervised clustered into six epitope groups (A-F), which is highly concordant with knowledge-based structural classifications3-5. Strikingly, various single mutations of Omicron could impair NAbs of different epitope groups. Specifically, NAbs in Group A-D, whose epitope overlap with ACE2-binding motif, are largely escaped by K417N, G446S, E484A, and Q493R. Group E (S309 site)6 and F (CR3022 site)7 NAbs, which often exhibit broad sarbecovirus neutralizing activity, are less affected by Omicron, but still, a subset of NAbs are escaped by G339D, N440K, and S371L. Furthermore, Omicron pseudovirus neutralization showed that single mutation tolerating NAbs could also be escaped due to multiple synergetic mutations on their epitopes. In total, over 85% of the tested NAbs are escaped by Omicron. Regarding NAb drugs, the neutralization potency of LY-CoV016/LY-CoV555, REGN10933/REGN10987, AZD1061/AZD8895, and BRII-196 were greatly reduced by Omicron, while VIR-7831 and DXP-604 still function at reduced efficacy. Together, data suggest Omicron would cause significant humoral immune evasion, while NAbs targeting the sarbecovirus conserved region remain most effective. Our results offer instructions for developing NAb drugs and vaccines against Omicron and future variants.

11.
Preprint in English | medRxiv | ID: ppmedrxiv-20218990

ABSTRACT

To discover new drugs to combat coronavirus disease 2019 (COVID-19), an understanding of the molecular basis of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection is urgently needed. Here, for the first time, we report the crucial role of cathepsin L (CTSL) in patients with COVID-19. The circulating level of CTSL was elevated and was positively correlated with disease course and severity in COVID-19 patients. Correspondingly, SARS-CoV-2 pseudovirus infection increased CTSL expression in human cell lines and human ACE2 transgenic mice, while CTSL overexpression, in turn, enhanced pseudovirus infection. CTSL functionally cleaved the SARS-CoV-2 spike protein and enhanced virus entry, as evidenced by CTSL overexpression and knockdown in vitro and application of CTSL inhibitor drugs in vivo. Furthermore, amantadine, a licensed anti-influenza drug, significantly inhibited CTSL activity and prevented SARS-CoV-2 pseudovirus infection. Therefore, CTSL is a promising target for new anti-COVID-19 drug development.

12.
Preprint in English | bioRxiv | ID: ppbiorxiv-360479

ABSTRACT

Dysfunctional immune response in the COVID-19 patients is a recurrent theme impacting symptoms and mortality, yet the detailed understanding of pertinent immune cells is not complete. We applied single-cell RNA sequencing to 284 samples from 205 COVID-19 patients and controls to create a comprehensive immune landscape. Lymphopenia and active T and B cell responses were found to coexist and associated with age, sex and their interactions with COVID-19. Diverse epithelial and immune cell types were observed to be virus-positive and showed dramatic transcriptomic changes. Elevation of ANXA1 and S100A9 in virus-positive squamous epithelial cells may enable the initiation of neutrophil and macrophage responses via the ANXA1-FPR1 and S100A8/9-TLR4 axes. Systemic upregulation of S100A8/A9, mainly by megakaryocytes and monocytes in the peripheral blood, may contribute to the cytokine storms frequently observed in severe patients. Our data provide a rich resource for understanding the pathogenesis and designing effective therapeutic strategies for COVID-19. HIGHLIGHTSO_LILarge-scale scRNA-seq analysis depicts the immune landscape of COVID-19 C_LIO_LILymphopenia and active T and B cell responses coexist and are shaped by age and sex C_LIO_LISARS-CoV-2 infects diverse epithelial and immune cells, inducing distinct responses C_LIO_LICytokine storms with systemic S100A8/A9 are associated with COVID-19 severity C_LI

13.
Cathrine Axfors; Andreas M Schmitt; Perrine Janiaud; Janneke van 't Hooft; Sherief Abd-Elsalam; Ehab F Abdo; Benjamin S Abella; Javed Akram; Ravi K Amaravadi; Derek C Angus; Yaseen M Arabi; Shehnoor Azhar; Lindsey R Baden; Arthur W Baker; Leila Belkhir; Thomas Benfield; Marvin A H Berrevoets; Cheng-Pin Chen; Tsung-Chia Chen; Shu-Hsing Cheng; Chien-Yu Cheng; Wei-Sheng Chung; Yehuda Z Cohen; Lisa N Cowan; Olav Dalgard; Fernando F de Almeida e Val; Marcus V G de Lacerda; Gisely C de Melo; Lennie Derde; Vincent Dubee; Anissa Elfakir; Anthony C Gordon; Carmen M Hernandez-Cardenas; Thomas Hills; Andy I M Hoepelman; Yi-Wen Huang; Bruno Igau; Ronghua Jin; Felipe Jurado-Camacho; Khalid S Khan; Peter G Kremsner; Benno Kreuels; Cheng-Yu Kuo; Thuy Le; Yi-Chun Lin; Wu-Pu Lin; Tse-Hung Lin; Magnus Nakrem Lyngbakken; Colin McArthur; Bryan McVerry; Patricia Meza-Meneses; Wuelton M Monteiro; Susan C Morpeth; Ahmad Mourad; Mark J Mulligan; Srinivas Murthy; Susanna Naggie; Shanti Narayanasamy; Alistair Nichol; Lewis A Novack; Sean M O'Brien; Nwora Lance Okeke; Lena Perez; Rogelio Perez-Padilla; Laurent Perrin; Arantxa Remigio-Luna; Norma E Rivera-Martinez; Frank W Rockhold; Sebastian Rodriguez-Llamazares; Robert Rolfe; Rossana Rosa; Helge Rosjo; Vanderson S Sampaio; Todd B Seto; Muhammad Shehzad; Shaimaa Soliman; Jason E Stout; Ireri Thirion-Romero; Andrea B Troxel; Ting-Yu Tseng; Nicholas A Turner; Robert J Ulrich; Stephen R Walsh; Steve A Webb; Jesper M Weehuizen; Maria Velinova; Hon-Lai Wong; Rebekah Wrenn; Fernando G Zampieri; Wu Zhong; David Moher; Steven N Goodman; John P A Ioannidis; Lars G Hemkens.
Preprint in English | medRxiv | ID: ppmedrxiv-20194571

ABSTRACT

Substantial COVID-19 research investment has been allocated to randomized clinical trials (RCTs) on hydroxychloroquine/chloroquine, which currently face recruitment challenges or early discontinuation. We aimed to estimate the effects of hydroxychloroquine and chloroquine on survival in COVID-19 from all currently available RCT evidence, published and unpublished. We conducted a rapid meta-analysis of ongoing, completed, or discontinued RCTs on hydroxychloroquine or chloroquine treatment for any COVID-19 patients (protocol: https://osf.io/QESV4/). We systematically identified unpublished RCTs (ClinicalTrials.gov, WHO International Clinical Trials Registry Platform, Cochrane COVID-registry up to June 11, 2020), and published RCTs (PubMed, medRxiv and bioRxiv up to October 16, 2020). All-cause mortality was extracted (publications/preprints) or requested from investigators and combined in random-effects meta-analyses, calculating odds ratios (ORs) with 95% confidence intervals (CIs), separately for hydroxychloroquine and chloroquine. Prespecified subgroup analyses included patient setting, diagnostic confirmation, control type, and publication status. Sixty-three trials were potentially eligible. We included 14 unpublished trials (1308 patients) and 14 publications/preprints (9011 patients). Results for hydroxychloroquine are dominated by RECOVERY and WHO SOLIDARITY, two highly pragmatic trials, which employed relatively high doses and included 4716 and 1853 patients, respectively (67% of the total sample size). The combined OR on all-cause mortality for hydroxychloroquine was 1.11 (95% CI: 1.02, 1.20; I2=0%; 26 trials; 10,012 patients) and for chloroquine 1.77 (95%CI: 0.15, 21.13, I2=0%; 4 trials; 307 patients). We identified no subgroup effects. We found that treatment with hydroxychloroquine was associated with increased mortality in COVID-19 patients, and there was no benefit of chloroquine. Findings have unclear generalizability to outpatients, children, pregnant women, and people with comorbidities.

14.
Preprint in English | medRxiv | ID: ppmedrxiv-20099754

ABSTRACT

BackgroundAcute respiratory infection (ARI) caused by RNA viruses is still one of the main diseases all over the world such as SARS-CoV-2 and Influenza A virus. mNGS was a powerful tool for ethological diagnosis. But there were some challenges during mNGS implementation in clinical settings such as time-consuming manipulation and lack of comprehensive analytical validation. MethodsWe set up CATCH that was a mNGS method based on RNA and DNA hybrid tagmentation via Tn5 transposon. Seven respiratory RNA viruses and three subtypes of Influenza A virus had been used to test CATCHs capabilities of detection and semiquantification. Analytical performance of SARS-CoV-2 and Influenza A virus had been determined with reference standards. We compared accuracy of CATCH with quantitative real time PCR by using clinical 98 samples from 64 COVID-19 patients. ResultsWe minimized the library preparation process to 3 hours and handling time to 35 minutes. Duplicate filtered RPM of 7 respiratory viruses and 3 Influenza A virus subtypes were highly correlated with viral concentration (r=0.60, p<0.001, Spearman correlation test). LOD of SARS-CoV-2 was 39.2 copies/test and of Influenza A virus was 278.1 copies/mL Comparing with qR-TPCR, the overall accuracy of CATCH was 91.4%. Sensitivity was 84.5% and specificity was 100%. Meanwhile, there were significant difference of microbial profile in oropharyngeal swabs among critical, moderate patients and healthy controls (p<0.001, PERMANOVA test). ConclusionAlthough further optimization is needed before CATCH can be rolled out as a routine diagnostic test, we highlight the potential impact of it advancing molecular diagnostics for respiratory pathogens.

15.
Preprint in English | medRxiv | ID: ppmedrxiv-20042184

ABSTRACT

WHO has declared COVID-19 a pandemic with more than 300,000 confirmed cases and more than 14,000 deaths. There is urgent need for accurate and rapid diagnostic kits. Here we report the development and validation of a COVID-19/SARS-CoV-2 S1 serology ELISA kit for the detection of total anti-virus antibody (IgG+IgM) titers in sera from either the general population or patients suspected to be infected. For indirect ELISA, CHO-expressed recombinant full length SARS-CoV-2-S1 protein with 6* His tag was used as the coating antigen to capture the SARS-CoV-2-S1 antibodies specifically. The specificity of the ELISA kit was determined to be 97.5%, as examined against total 412 normal human sera including 257 samples collected prior to the outbreak and 155 collected during the outbreak. The sensitivity of the ELISA kit was determined to be 97.5% by testing against 69 samples from hospitalized and/or recovered COVID-19 patients. The overall accuracy rate reached 97.3%. Most importantly, in one case study, the ELISA test kit was able to identify an infected person who had previously been quarantined for 14 days after coming into contact with a confirmed COVID-19 patient, and discharged after testing negative twice by nucleic acid test. With the assays developed here, we can screen millions of medical staffs in the hospitals and people in residential complex, schools, public transportations, and business parks in the epidemic centers of the outbreaks to fish out the "innocent viral spreaders", and help to stop the further spreading of the virus.

16.
Preprint in English | medRxiv | ID: ppmedrxiv-20025999

ABSTRACT

The COVID-19 China coronavirus started in Dec 2019 was challenged by the lack of accurate serological diagnostic tool for this deadly disease to quickly identify and isolate the infected patients. The generation of COVID-19-specific antibodies is essential for such tasks. Here we report that polyclonal and monoclonal antibodies were generated by immunizing animals with synthetic peptides corresponding to different areas of Nucleoprotein (N) of COVID-19. The specificities of the COVID-19 antibodies were assessed by Western Blot analysis against NPs from COVID-19, MERS and SARS. Antibodies were used for immunohistochemistry staining of the tissue sections from COVID-19 infected patient, as a potential diagnostic tool. A Sandwich ELISA kit was quickly assembled for quantitation of the virus/NP of COVID-19 concentrations in the vaccine preparations. Development of POCT is also aggressively undergoing.

17.
Chinese Journal of Burns ; (6): 629-633, 2017.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-809396

ABSTRACT

Objective@#To investigate the situations of on-site rescue and traumatic features of victims involved in gas explosion accident in Hangzhou, so as to provide more data support for emergency medical rescues of the similar incidents of massive casualty.@*Methods@#Two medical workers with a certain clinical experience were sent to Hangzhou 120 emergency medical centers to collect data of the on-site rescue on 21st July, 2017, including ambulance call-outs, on-site command and traffic conditions, and on-site triage and evacuation of the victims. They were then sent to the hospitals receiving the victims to investigate the situations of these victims including the general information (such as gender, age, admitted hospitals, and number of admission, discharge, and transferring in the first two weeks after the accident) and injury assessment [such as injury position and type, injury severity evaluation by New Injury Severity Scoring (NISS), and burn severity evaluation for victims with burns].@*Results@#(1) A total of 15 ambulances reached the accident site for rescue. The traffic and transportation were jammed and interrupted after this accident. On-site triage and distribution were disorderly conducted. (2) Clinical data of 53 victims were collected, including 24 males and 29 females, with the age of 8 to 70 (34±14) years old. They were sent into 6 hospitals in Hangzhou. Two victims died on the day of accident. Up to two weeks after this accident, 28 (52.8%) victims were discharged from the hospitals and received follow-up in outpatient department. Five victims with severe injuries were transferred to the other hospitals. (3) Based on the results of NISS, the injury severities were mild in 29 (54.7%) cases, moderate in 9 (17.0%) cases, serious in 3 (5.7%) cases, and severe in 12 (22.6%) cases. Those 2 dead victims were classified into the severe category due to the highest NISS score of 75. For all of the victims, skin and soft tissue defects were most common. Six (11.3%) victims were combined with burns. According to the classification of burn severity, there were one case of mild, one case of serious, and 4 cases of severe.@*Conclusions@#The gas explosion accident in Hangzhou caused massive casualties with complex injuries. The local emergency medical rescue responded quickly, but during the rescue process, lots of aspects should be further improved.

18.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-476435

ABSTRACT

Combined antiretroviral therapy ( cART) is widely used for infections of human immune deficiency virus ( HIV) .However , some antiviral drugs can not reach the effective concentrations in central nervous system due to the hinder of blood-brain barrier ( BBB) , resulting in the formation of viral reservoir in central nervous system .BBB is formed by human brain microvascular endothelial cells ( HBMVECs ) , which are connected by tight junction and a thick basement membrane , and astrocytic end-feet.This paper reviews possible mechanisms of BBB hindrance and anti-HIV drug efflux by transport proteins , as well as effective methods to deliver antiretroviral drugs into brain , including the application of nano technology .

19.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-438864

ABSTRACT

Great difficulties were existed in clinical teaching in hospitals for infectious diseases. Therefore,a centralized hospital teaching rounds,a new clinical teaching practice was taken in a hospital for infectious diseases. During seven years' practice,a basic mode of centralized hospital teaching rounds was established,which contains many aspects such as organizational form,time arrangement,case se-lection and operation procedures. Its effectiveness was evaluated accoding to the following aspects:number of people attending hospital teaching rounds,composition of these people,satisfaction of these people, comparison of ward rounds data recorded nowadays and 7 years before and assembling all the rounds records into a book. Results indicated that this measure overcame the limitations of the specialized hospi-tals to some extent and played an important role in improving clinical teaching quality.

20.
Chinese Journal of Hepatology ; (12): 52-54, 2002.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-257887

ABSTRACT

<p><b>OBJECTIVE</b>To raise the accuracy of clinical diagnosis of chronic hepatitis B.</p><p><b>METHODS</b>The correlation between the clinical features, biochemical tests (the serum total bilirubin-TBil, albumin-ALB, prothrobin activity-PTA, alanine aminotransferase-ALT, albumin/globulin-A/G, and r-globulin-r-G) and histopathological data in 202 patients with chronic hepatitis B (CHB) were studied.</p><p><b>RESULTS</b>Some of presenting symptoms and signs were obviously associated with histological grade and stage. The grade of necroinflammatory activity of CHB was associated with the rising TBil, ALT, GGT and the declining ALB, A/G and PTA. The coincidence of clinical diagnosis and pathology was highest in mild chronic hepatitis, 63.8%~79.0%; then was in marked chronic hepatitis, 40.0%~62.5%. The coincidence was lowest in moderate chronic hepatitis, 10.0%~28.2%.</p><p><b>CONCLUSIONS</b>Great attention should be paid to the significance of symptoms and signs, meanwhile the standard of clinical diagnosis for moderate chronic hepatitis might be relaxed somewhat.</p>


Subject(s)
Adolescent , Adult , Aged , Female , Humans , Male , Middle Aged , Alanine Transaminase , Blood , Bilirubin , Blood , Biomarkers , Blood , Clinical Medicine , Hepatitis B, Chronic , Blood , Diagnosis , Pathology , Histological Techniques , Prothrombin
SELECTION OF CITATIONS
SEARCH DETAIL
...