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1.
Comput Struct Biotechnol J ; 19: 1976-1985, 2021.
Article in English | MEDLINE | ID: covidwho-2287138

ABSTRACT

With the global epidemic of SARS-CoV-2, it is important to effectively monitor the variation, haplotype subgroup epidemic trends and key mutations of SARS-CoV-2 over time. This is of great significance to the development of new vaccines, the update of therapeutic drugs, and the improvement of detection methods. The AutoVEM tool developed in the present study could complete all mutations detections, haplotypes classification, haplotype subgroup epidemic trends and candidate key mutations analysis for 131,576 SARS-CoV-2 genome sequences in 18 h on a 1 core CPU and 2 GB RAM computer. Through haplotype subgroup epidemic trends analysis of 131,576 genome sequences, the great significance of the previous 4 specific sites (C241T, C3037T, C14408T and A23403G) was further revealed, and 6 new mutation sites of highly linked (T445C, C6286T, C22227T, G25563T, C26801G and G29645T) were discovered for the first time that might be related to the infectivity, pathogenicity or host adaptability of SARS-CoV-2. In brief, we proposed an integrative method and developed an efficient automated tool to monitor haplotype subgroup epidemic trends and screen for the candidate key mutations in the evolution of SARS-CoV-2 over time for the first time, and all data could be updated quickly to track the prevalence of previous key mutations and new candidate key mutations because of high efficiency of the tool. In addition, the idea of combinatorial analysis in the present study can also provide a reference for the mutation monitoring of other viruses.

2.
Comput Struct Biotechnol J ; 19: 5029-5038, 2021.
Article in English | MEDLINE | ID: covidwho-2287137

ABSTRACT

In our previous work, we developed an automated tool, AutoVEM, for real-time monitoring the candidate key mutations and epidemic trends of SARS-CoV-2. In this research, we further developed AutoVEM into AutoVEM2. AutoVEM2 is composed of three modules, including call module, analysis module, and plot module, which can be used modularly or as a whole for any virus, as long as the corresponding reference genome is provided. Therefore, it's much more flexible than AutoVEM. Here, we analyzed three existing viruses by AutoVEM2, including SARS-CoV-2, HBV and HPV-16, to show the functions, effectiveness and flexibility of AutoVEM2. We found that the N501Y locus was almost completely linked to the other 16 loci in SARS-CoV-2 genomes from the UK and Europe. Among the 17 loci, 5 loci were on the S protein and all of the five mutations cause amino acid changes, which may influence the epidemic traits of SARS-CoV-2. And some candidate key mutations of HBV and HPV-16, including T350G of HPV-16 and C659T of HBV, were detected. In brief, we developed a flexible automated tool to analyze candidate key mutations and epidemic trends for any virus, which would become a standard process for virus analysis based on genome sequences in the future.

3.
Front Neurol ; 14: 1037673, 2023.
Article in English | MEDLINE | ID: covidwho-2264698

ABSTRACT

Background: Skull osteosarcoma is relatively rare, and it is difficult to be diagnosed according to medical history and imaging examination due to the complex structure and diverse components of the brain. Consequently, there is only a limited number of patients who can undergo neoadjuvant chemotherapy before the operation. Although neoadjuvant chemotherapy plays an important role in the treatment of osteosarcoma, there is still a "bottleneck" in the current treatment method which when pulmonary metastasis occurs, or surgical treatment is not Enneking appropriate. Under such circumstances, the choice of treatment can be an issue. Case: A 16-year-old male patient with multiple metastases of skull osteosarcoma was reported. The patient suffered not only tinnitus and hearing loss in the right ear but also right facial paralysis and headache. The preoperative brain MRI showed a tumor in the right cerebellopontine angle (CPA) area. He underwent skull tumor resection at another hospital in November 2018, during which process the biopsy revealed epithelioid osteoblastoma-like osteosarcoma. The patient had supplemental radiotherapy 1 month after surgery because of tumor recurrence. 32 months afterward, pulmonary metastases and multiple bone metastases were found. Then the patient underwent multiple conservative treatments which include Denosumab, Anlotinib, and DIA (cisplatin + ifosfamide + doxorubicin) chemotherapy at our hospital. After a series of 6 cycles of treatment, the patient can walk without aid. Lactate dehydrogenase (LDH) and Alkaline phosphatase (AKP) returned to a normal level. Fluorodeoxyglucose (FDG) metabolism in all bone metastases decreased to normal except for the ones in the proximal left femur, and the FDG metabolism in the left femur is significantly lower than that before treatment. Multiple bone metastases showed different extents of high-density calcification, and the volume of the local bone metastases has been reduced significantly. The patient's condition stayed stable at latest follow-up. Conclusion: We found that multiple conservative treatments, which include Denosumab, Anlotinib and DIA chemotherapy, can improve patients' life quality, and help avoid further osteolytic destruction for patients with skull osteosarcoma and multiple metastases. Its specific mechanism and scope of the application still need to be further studied.

4.
Emerg Microbes Infect ; 11(1): 2120-2131, 2022 Dec.
Article in English | MEDLINE | ID: covidwho-1967813

ABSTRACT

Spike (S) glycoprotein is the most significant structural protein of SARS-CoV-2 and a key target for neutralizing antibodies. In light of the on-going SARS-CoV-2 pandemic, identification and screening of epitopes of spike glycoproteins will provide vital progress in the development of sensitive and specific diagnostic tools. In the present study, NTD, RBD, and S2 genes were inserted into the pcDNA3.1(+) vector and designed with N-terminal 6× His-tag for fusion expression in HEK293F cells by transient transfection. Six monoclonal antibodies (4G, 9E, 4B, 7D, 8F, and 3D) were prepared using the expressed proteins by cell fusion technique. The characterization of mAbs was performed by indirect -ELISA, western blot, and IFA. We designed 49 overlapping synthesized peptides that cover the extracellular region of S protein in which 6 amino acid residues were offset between adjacent (S1-S49). Peptides S12, S19, and S49 were identified as the immunodominant epitope regions by the mAbs. These regions were further truncated and the peptides S12.2 286TDAVDCALDPLS297, S19.2 464FERDISTEIYQA475, and S49.4 1202ELGKYEQYIKWP1213 were identified as B- cell linear epitopes for the first time. Alanine scans showed that the D467, I468, E471, Q474, and A475 of the epitope S19.2 and K1205, Q1208, and Y1209 of the epitope S49.4 were the core sites involved in the mAbs binding. The multiple sequence alignment analysis showed that these three epitopes were highly conserved among the variants of concern (VOCs) and variants of interest (VOIs). Taken together, the findings provide a potential material for rapid diagnosis methods of COVID-19.


Subject(s)
Epitopes, B-Lymphocyte , SARS-CoV-2 , Spike Glycoprotein, Coronavirus , Amino Acid Sequence , Antibodies, Monoclonal , Antibodies, Neutralizing , Antibodies, Viral , COVID-19 , Epitopes, B-Lymphocyte/genetics , Humans , Membrane Glycoproteins/genetics , Peptides , SARS-CoV-2/genetics , Spike Glycoprotein, Coronavirus/genetics , Viral Envelope Proteins
5.
Viruses ; 14(3)2022 02 23.
Article in English | MEDLINE | ID: covidwho-1699562

ABSTRACT

The scale of SARS-CoV-2 infection and death is so enormous that further study of the molecular and evolutionary characteristics of SARS-CoV-2 will help us better understand and respond to SARS-CoV-2 outbreaks. The present study analyzed the epidemic and evolutionary characteristics of haplotype subtypes or regions based on 1.8 million high-quality SARS-CoV-2 genomic data. The estimated ratio of the rates of non-synonymous to synonymous changes (Ka/Ks) in North America and the United States were always more than 1.0, while the Ka/Ks in other continents and countries showed a sharp decline, then a slow increase to 1.0, and a dramatic increase over time. H1 (B.1) with the highest substitution rate has become the most dominant haplotype subtype since March 2020 and has evolved into multiple haplotype subtypes with smaller substitution rates. Many evolutionary characteristics of early SARS-CoV-2, such as H3 being the only early haplotype subtype that existed for the shortest time, the global prevalence of H1 and H1-5 (B.1.1) within a month after being detected, and many high divergent genome sequences early in February 2020, indicate the missing of early SARS-CoV-2 genomic data. SARS-CoV-2 experienced dynamic selection from December 2019 to August 2021 and has been under strong positive selection since May 2021. Its transmissibility and the ability of immune escape may be greatly enhanced over time. This will bring greater challenges to the control of the pandemic.


Subject(s)
COVID-19 , SARS-CoV-2 , COVID-19/epidemiology , Haplotypes , Humans , Mutation, Missense , Phylogeny , SARS-CoV-2/genetics
6.
Telemed J E Health ; 28(7): 1064-1069, 2022 07.
Article in English | MEDLINE | ID: covidwho-1569563

ABSTRACT

Introduction: Testing facilities for COVID-19 were stood up around the country during the pandemic, but could not handle the demand. This study aimed to combine a mobile application (App) with an at-home test kit to facilitate home-based testing. Methods: After integrating an App with an at-home testing service, we measured the time between sample collection and notification of results. We recruited 92 volunteers to utilize the platform. Results: Sixty-one percent (55/92) responded to the survey. Median sample collection-to-result time was 2.2 days (IQR = 1.3-3.2). Eighty-two percent (45/55) found the self-test kit and App easy to use. Eighty-four percent agreed that the combined solution is an acceptable way to receive health care services. Discussion: Decreasing testing time and providing timely test results improve care access and decrease the risk of infection. Combining a tailored App with an at-home testing service is a feasible solution to reaching that goal.


Subject(s)
COVID-19 , Mobile Applications , COVID-19/epidemiology , Humans , Pandemics , Surveys and Questionnaires
7.
Int J Infect Dis ; 100: 164-173, 2020 Nov.
Article in English | MEDLINE | ID: covidwho-943165

ABSTRACT

OBJECTIVES: To further reveal the phylogenetic evolution and molecular characteristics of the whole genome of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) based on a large number of genomes and provide a basis for the prevention and treatment of SARS-CoV-2. METHODS: Various evolution analysis methods were employed. RESULTS: The estimated ratio of the rates of non-synonymous to synonymous changes (Ka/Ks) of SARS-CoV-2 was 1.008 or 1.094 based on 622 or 3624 SARS-CoV-2 genomes and nine key specific sites of high linkage, and four major haplotypes were found: H1, H2, H3 and H4. The results of Ka/Ks, detected population size and development trends of each major haplotype showed that H3 and H4 subgroups were going through a purify evolution and almost disappeared after detection, indicating that they might have existed for a long time. The H1 and H2 subgroups were going through a near neutral or neutral evolution and globally increased with time, and the frequency of H1 was generally high in Europe and correlated with the death rate (r >0.37), suggesting that these two haplotypes might relate to the infectivity or pathogenicity of SARS-CoV-2. CONCLUSIONS: Several key specific sites and haplotypes related to the infectivity or pathogenicity of SARS-CoV-2, and the possible earlier origin time and place of SARS-CoV-2 were indicated based on the evolution and epidemiology of 16,373 SARS-CoV-2 genomes.


Subject(s)
COVID-19/epidemiology , Genome, Viral , SARS-CoV-2/genetics , Europe/epidemiology , Evolution, Molecular , Haplotypes , Humans , Pandemics , Phylogeny
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