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1.
BMC Infect Dis ; 23(1): 305, 2023 May 08.
Artículo en Inglés | MEDLINE | ID: covidwho-2320310

RESUMEN

BACKGROUND: Although there is increasing understanding of the changes in the laboratory parameters of Coronavirus disease 2019 (COVID-19), the correlation between circulating Mid-regional Proadrenomedullin (MR-proADM) and mortality of patients with COVID-19 is not fully understood. In this study, we conducted a systematic review and meta-analysis to evaluate the prognostic value of MR-proADM in patients with COVID-19. METHODS: The PubMed, Embase, Web of Science, Cochrane Library, Wanfang, SinoMed and Chinese National Knowledge Infrastructure (CNKI) databases were searched from 1 January 2020 to 20 March 2022 for relevant literature. The Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2) was used to assess quality bias, STATA was employed to pool the effect size by a random effects model, and potential publication bias and sensitivity analyses were performed. RESULTS: 14 studies comprising 1822 patients with COVID-19 met the inclusion criteria, there were 1145 (62.8%) males and 677 (31.2%) females, and the mean age was 63.8 ± 16.1 years. The concentration of MR-proADM was compared between the survivors and non-survivors in 9 studies and the difference was significant (P < 0.01), I2 = 46%. The combined sensitivity was 0.86 [0.73-0.92], and the combined specificity was 0.78 [0.68-0.86]. We drew the summary receiver operating characteristic (SROC) curve and calculated the area under curve (AUC) = 0.90 [0.87-0.92]. An increase of 1 nmol/L of MR-proADM was independently associated with a more than threefold increase in mortality (odds ratio (OR) 3.03, 95% confidence interval (CI) 2.26-4.06, I2 = 0.0%, P = 0.633). The predictive value of MR-proADM for mortality was better than many other biomarkers. CONCLUSION: MR-proADM had a very good predictive value for the poor prognosis of COVID-19 patients. Increased levels of MR-proADM were independently associated with mortality in COVID-19 patients and may allow a better risk stratification.


Asunto(s)
COVID-19 , Femenino , Masculino , Humanos , Persona de Mediana Edad , Anciano , Adrenomedulina , Área Bajo la Curva , Pueblo Asiatico
2.
Math Biosci Eng ; 20(5): 9327-9348, 2023 03 16.
Artículo en Inglés | MEDLINE | ID: covidwho-2298959

RESUMEN

The coronavirus disease 2019 (COVID-19) outbreak has resulted in countless infections and deaths worldwide, posing increasing challenges for the health care system. The use of artificial intelligence to assist in diagnosis not only had a high accuracy rate but also saved time and effort in the sudden outbreak phase with the lack of doctors and medical equipment. This study aimed to propose a weakly supervised COVID-19 classification network (W-COVNet). This network was divided into three main modules: weakly supervised feature selection module (W-FS), deep learning bilinear feature fusion module (DBFF) and Grad-CAM++ based network visualization module (Grad-Ⅴ). The first module, W-FS, mainly removed redundant background features from computed tomography (CT) images, performed feature selection and retained core feature regions. The second module, DBFF, mainly used two symmetric networks to extract different features and thus obtain rich complementary features. The third module, Grad-Ⅴ, allowed the visualization of lesions in unlabeled images. A fivefold cross-validation experiment showed an average classification accuracy of 85.3%, and a comparison with seven advanced classification models showed that our proposed network had a better performance.


Asunto(s)
Inteligencia Artificial , COVID-19 , Humanos , COVID-19/epidemiología , Brotes de Enfermedades , Proyectos de Investigación , Tomografía Computarizada por Rayos X
3.
Sci China Life Sci ; 2023 Apr 14.
Artículo en Inglés | MEDLINE | ID: covidwho-2297189

RESUMEN

Protein-biomolecule interactions play pivotal roles in almost all biological processes. For a biomolecule of interest, the identification of the interacting protein(s) is essential. For this need, although many assays are available, highly robust and reliable methods are always desired. By combining a substrate-based proximity labeling activity from the pupylation pathway of Mycobacterium tuberculosis and the streptavidin (SA)-biotin system, we developed the Specific Pupylation as IDEntity Reporter (SPIDER) method for identifying protein-biomolecule interactions. Using SPIDER, we validated the interactions between the known binding proteins of protein, DNA, RNA, and small molecule. We successfully applied SPIDER to construct the global protein interactome for m6A and mRNA, identified a variety of uncharacterized m6A binding proteins, and validated SRSF7 as a potential m6A reader. We globally identified the binding proteins for lenalidomide and CobB. Moreover, we identified SARS-CoV-2-specific receptors on the cell membrane. Overall, SPIDER is powerful and highly accessible for the study of protein-biomolecule interactions.

4.
Pharmaceutics ; 15(3)2023 Feb 26.
Artículo en Inglés | MEDLINE | ID: covidwho-2297179

RESUMEN

Nanomedicine is a branch of medicine using nanotechnology to prevent and treat diseases. Nanotechnology represents one of the most effective approaches in elevating a drug's treatment efficacy and reducing toxicity by improving drug solubility, altering biodistribution, and controlling the release. The development of nanotechnology and materials has brought a profound revolution to medicine, significantly affecting the treatment of various major diseases such as cancer, injection, and cardiovascular diseases. Nanomedicine has experienced explosive growth in the past few years. Although the clinical transition of nanomedicine is not very satisfactory, traditional drugs still occupy a dominant position in formulation development, but increasingly active drugs have adopted nanoscale forms to limit side effects and improve efficacy. The review summarized the approved nanomedicine, its indications, and the properties of commonly used nanocarriers and nanotechnology.

5.
Analyst ; 148(6): 1214-1220, 2023 Mar 13.
Artículo en Inglés | MEDLINE | ID: covidwho-2288540

RESUMEN

Timely and accurate diagnosis of COVID-19 is critical for controlling the pandemic. As the standard method to diagnose SARS-CoV-2, the real-time reverse transcription polymerase chain reaction (RT-qPCR) has good convenience. However, RT-qPCR still has a relatively high false-negative rate, particularly in the case of detecting low viral loads. In this study, using selenium-modified nucleoside triphosphates (dNTPαSe) in the RT-PCR reactions, we successfully increased the detection sensitivity and reduced the false-negative rate in COVID-19 diagnosis. By detecting positive controls, pseudovirus, and clinical samples with the commercial kits, we found that the dNTPαSe supplementation to these kits could generally offer smaller Ct values, permit the viral detection even in single-digit copies, and increase the detection specificity, sensitivity, and accuracy, thereby reducing the false-negative rate. Our experimental results demonstrated that dNTPαSe supplementation can make the commercial kits more specific, sensitive, and accurate, and this method is a convenient and efficient strategy for the disease detection and diagnosis.


Asunto(s)
COVID-19 , Humanos , COVID-19/diagnóstico , SARS-CoV-2/genética , Prueba de COVID-19 , Errores Diagnósticos , Reacción en Cadena en Tiempo Real de la Polimerasa/métodos , Sensibilidad y Especificidad , Suplementos Dietéticos , ARN Viral
6.
J Affect Disord ; 329: 343-349, 2023 05 15.
Artículo en Inglés | MEDLINE | ID: covidwho-2288408

RESUMEN

BACKGROUND: The outbreak of COVID-19 disarranged lives across mainland China. No study has examined changes in psychological symptoms of healthcare professionals in the intensive care unit (ICU) before and after the outbreak of COVID-19. The aim of this study was to estimate changes in psychological symptoms of ICU healthcare professionals before and after the COVID-19 outbreak, and to analyze factors related to psychological symptoms. METHODS: Two waves' administrations were implemented between December 13 and December 14, 2018, and between April 5 and April 7, 2020, respectively. The symptom checklist-90 (SCL-90) were used to evaluate psychological symptoms. Multiple logistical regression was used to reveal the risk of psychological symptoms. RESULTS: A total of 3902 and 3908 ICU healthcare professionals took part in the first and second surveys. The mean total score of the SCL-90 was 179.27 (70.02) at wave 1 and 147.75 (58.40) at wave 2, respectively. The proportion of psychological symptoms was 55.6 % (95%CI = 54.0-57.1) at wave 1. But rates of psychological symptoms decreased to 36.6 % (95%CI = 35.1-38.2) at wave 2. ICU healthcare professionals with western economic belt and 6-10 years of work were more likely to develop psychological symptoms, while ICU healthcare professionals with the later survey and doctoral degree were less likely to develop psychological symptoms. CONCLUSION: Although COVID-19 period benefited psychological symptoms of ICU healthcare professionals, psychological symptoms still had a related high prevalence. Regular screening and appropriate interventions should still be implemented to decrease the risk for psychological symptoms among Chinese ICU healthcare professionals.


Asunto(s)
COVID-19 , Personal de Salud , Unidades de Cuidados Intensivos , Humanos , COVID-19/epidemiología , Estudios Transversales , Atención a la Salud , Brotes de Enfermedades , Pueblos del Este de Asia , Personal de Salud/psicología
8.
Pathogens ; 12(2)2023 Feb 12.
Artículo en Inglés | MEDLINE | ID: covidwho-2257652

RESUMEN

Adenosine diphosphate (ADP)-ribosylation is a reversible post-translational modification catalyzed by ADP-ribosyltransferases (ARTs). ARTs transfer one or more ADP-ribose from nicotinamide adenine dinucleotide (NAD+) to the target substrate and release the nicotinamide (Nam). Accordingly, it comes in two forms: mono-ADP-ribosylation (MARylation) and poly-ADP-ribosylation (PARylation). ADP-ribosylation plays important roles in many biological processes, such as DNA damage repair, gene regulation, and energy metabolism. Emerging evidence demonstrates that ADP-ribosylation is implicated in host antiviral immune activity. Here, we summarize and discuss ADP-ribosylation modifications that occur on both host and viral proteins and their roles in host antiviral response.

9.
Asian J Pharm Sci ; 2022 Nov 17.
Artículo en Inglés | MEDLINE | ID: covidwho-2262541

RESUMEN

The liposome is the first nanomedicine transformed into the market and applied to human patients. Since then, such phospholipid bilayer vesicles have undergone technological advancements in delivering small molecular-weight compounds and biological drugs. Numerous investigations about liposome uses were conducted in different treatment fields, including anti-tumor, anti-fungal, anti-bacterial, and clinical analgesia, owing to liposome's ability to reduce drug cytotoxicity and improve the therapeutic efficacy and combinatorial delivery. In particular, two liposomal vaccines were approved in 2021 to combat COVID-19. Herein, the clinically used liposomes are reviewed by introducing various liposomal preparations in detail that are currently proceeding in the clinic or on the market. Finally, we will discuss the challenges of developing liposomes and cutting-edge liposomal delivery for biological drugs and combination therapy.

10.
Int J Biol Macromol ; 234: 123635, 2023 Apr 15.
Artículo en Inglés | MEDLINE | ID: covidwho-2246765

RESUMEN

Respiratory viral infections, such as coronavirus disease of 2019 (COVID-19) and influenza, cause significant morbidity and mortality and have become a worldwide public health concern with tremendous economic and societal burdens. Vaccination is a major strategy for preventing infections. However, some new vaccines have an unmet need for impairing responses in certain individuals, especially COVID-19 vaccines, despite ongoing vaccine and adjuvant research. Here, we evaluated the effectiveness of Astragalus polysaccharide (APS), a bioactive polysaccharide extracted from the traditional Chinese herb Astragalus membranaceus as an immune adjuvant to regulate the efficacy of influenza split vaccine (ISV) and recombinant severe acute respiratory syndrome (SARS)-Cov-2 vaccine in mice. Our data indicated that APS as an adjuvant can facilitate the induction of high levels of hemagglutination inhibition (HAI) titer and specific antibody immunoglobulin G (IgG) and confer protection against the lethal challenge of influenza A viruses, including increased survival and amelioration of weight loss in mice immunized with the ISV. RNA sequencing (RNA-seq) analysis revealed that the NF-κB and Fc gamma R-mediated phagocytosis signaling pathways are essential for the immune response of mice immunized with the recombinant SARS-Cov-2 vaccine (RSV). Another important finding was that bidirectional immunomodulation of APS on cellular and humoral immunity was observed, and APS-adjuvant-induced antibodies persisted at a high level for at least 20 weeks. These findings suggest that APS is a potent adjuvant for influenza and COVID-19 vaccines, and has the advantages of bidirectional immunoregulation and persistent immunity.


Asunto(s)
COVID-19 , Vacunas contra la Influenza , Gripe Humana , Animales , Ratones , Humanos , Vacunas contra la COVID-19 , Anticuerpos Antivirales , COVID-19/prevención & control , SARS-CoV-2 , Adyuvantes Inmunológicos/farmacología , Adyuvantes Farmacéuticos , Inmunidad Humoral , Polisacáridos/farmacología
11.
Proteomics ; : e2200306, 2022 Oct 07.
Artículo en Inglés | MEDLINE | ID: covidwho-2242447

RESUMEN

The majority of people in China have been immunized with the inactivated viral vaccine BBIBP-CorV. The emergence of the Omicron variant raised the concerns about protection efficacy of the inactivated viral vaccine in China. However, longitudinal neutralization data describing protection efficacy against Omicron variant is still lacking. Here we present one-year longitudinal neutralization data of BBIBP-CorV on authentic Omicron, Delta, and wild-type strains using 224 sera collected from 14 volunteers who have finished three doses BBIBP-CorV. The sera were also subjected for monitoring the SARS-CoV-2 specific IgG, IgA, and IgM responses on protein and peptide microarrays. The neutralization titers showed different protection efficacies against the three strains. By incorporating IgG and IgA signals of proteins and Spike protein derived peptide on microarray, panels as potential surrogate biomarkers for rapid estimation of neutralization titers were established. These data support the necessity of the 3rd dose of BBIBP-CorV vaccination. After further validation and assay development, the panels could be used for reliable, convenient and fast evaluation of the efficacy of vaccination.

12.
Int J Environ Res Public Health ; 20(2)2023 Jan 11.
Artículo en Inglés | MEDLINE | ID: covidwho-2232546

RESUMEN

Background: The psychological status of men who have sex with men (MSM) as a vulnerable population during COVID-19 is worthy of attention. However, studies of Chinese MSM are limited. The aim of this study was to investigate the psychological status and influencing factors of MSM population and to provide a scientific basis for this group to actively respond to public health emergencies. Methods: From June to September 2020, we conducted an online survey. MSMs were recruited through collaboration with non-governmental organizations (NGOs) and peer recommendations. The variables we collected included four aspects: demographic and HIV-related characteristics; COVID-19-related knowledge, attitudes, and behaviors; COVID-19-related risk perception; epidemic exposure. The psychological status was assessed by the Psychological Questionnaire for Emergent Events of Public Health (PQEEPH), which defined the psychological status as five primary disorders: depression, neurasthenia, fear, anxiety, and hypochondria. Multivariate logistic regression was used to explore the influences of COVID-19-related factors on the psychological status. Results: We surveyed 412 MSM online during COVID-19. The five psychological status of high-risk states accounted for 16.99% (depression), 14.08% (neurasthenia), 16.75% (fear), 16.50% (anxiety), and 18.20% (hypochondria), respectively. Not being well-informed about the causes of COVID-19 (p = 0.020) and having experienced epidemic exposure (p = 0.006) were able to promote the occurrence of depression. Lack of knowledge of the curative effect of COVID-19 has a higher risk of occurrence neurasthenia (p < 0.001). Being afraid of the novel coronavirus (p < 0.001) promoted fear. The perceived prevalence of the epidemic (p = 0.003), being more susceptible to COVID-19 (p < 0.001), and not being well-informed about the causes of COVID-19 (p = 0.005) had a positive effect on anxiety. Considering that the epidemic was not effectively controlled (p = 0.017), being more susceptible to COVID-19 (p < 0.001) was a contributing factor to the hypochondria. Conclusions: The incidence of psychological disorders in Chinese MSM was higher than that in other groups during COVID-19. Factors associated with COVID-19 may cause a range of mental health problems in this population. Greater attention should be paid to the mental health status of special populations during the epidemic, and effective preventive education and intervention measures should be taken.


Asunto(s)
COVID-19 , Minorías Sexuales y de Género , Masculino , Humanos , COVID-19/epidemiología , Estudios Transversales , Homosexualidad Masculina/psicología , SARS-CoV-2 , Ansiedad/epidemiología , Ansiedad/psicología , Encuestas y Cuestionarios , China/epidemiología , Depresión/epidemiología
14.
BMC Neurol ; 23(1): 25, 2023 Jan 17.
Artículo en Inglés | MEDLINE | ID: covidwho-2230869

RESUMEN

BACKGROUND: Tolosa-Hunt syndrome (THS) is characterized by painful ophthalmoplegia caused by idiopathic granulomatous inflammation involving the cavernous sinus region. Patients respond well to steroid therapy. THS is included in the differential diagnosis of cavernous sinus syndrome, so it is important to fully exclude other lesions in this area before treatment, otherwise steroid treatment may lead to fatal outcomes. Here we describe a patient who initially presented with symptoms that simulated THS symptoms and developed recurrent alternating painful ophthalmoplegia during follow-up, and the patient was finally diagnosed with cavernous sinusitis caused by bacterial sphenoid sinusitis. CASE PRESENTATION: A 34-year-old woman presented with left painful ophthalmoplegia. Magnetic resonance imaging (MRI) revealed abnormal signals in the left cavernous sinus area, and these abnormal signals were suspected to be THS. After steroid treatment, the patient obtained pain relief and had complete recovery of her ophthalmoplegia. However, right painful ophthalmoplegia appeared during the follow-up period. MRI showed obvious inflammatory signals in the right cavernous sinus and right sphenoid sinus. Then nasal sinus puncture and aspiration culture were performed, and the results showed a coagulase-negative staphylococcus infection. After antibiotic treatment with vancomycin, the painful ophthalmoplegia completely resolved, and the neurological examination and MRI returned to normal. CONCLUSION: Some other causes of painful ophthalmoplegia also fulfill the diagnostic criteria for THS in the International Classification of Headache Disorders third edition (ICHD-3) and respond well to steroid therapy. Early diagnosis of THS may be harmful to patients, and clinicians should exercise great caution when dealing with similar cases without a biopsy. Using "cavernous sinus syndrome" instead of "Tolosa-Hunt syndrome" as a diagnostic category may provide a better clinical thinking for etiological diagnosis.


Asunto(s)
Oftalmoplejía , Sinusitis , Sinusitis del Esfenoides , Humanos , Femenino , Adulto , Sinusitis del Esfenoides/diagnóstico , Sinusitis del Esfenoides/diagnóstico por imagen , Imagen por Resonancia Magnética , Sinusitis/complicaciones , Oftalmoplejía/diagnóstico , Esteroides/uso terapéutico
15.
Disaster Med Public Health Prep ; : 1-24, 2022 Mar 04.
Artículo en Inglés | MEDLINE | ID: covidwho-2230867

RESUMEN

OBJECTIVE: Wearing face masks is believed to mitigate COVID-19 virus transmission by filtering respiratory droplets. This study was to explore the factors influencing wearing face masks in public in China during COVID-19 outbreak. METHODS: This study was a qualitative semi-structured interview research design and was guided by the Protection Motivation Theory. Participants from Jiangxi Province China were interviewed via WeChat video call. Thematic analysis was used to analyze the data. RESULTS: Recruitment efforts were suspended when 21 participants (aged 23 to 72) were successfully enrolled and the data reached thematic saturation. Four themes were identified when participants described factors influencing them to wear face masks: knowledge of disease (subthemes were severity of disease, and individual vulnerability to disease), environmental facilitators and constraints (subthemes were government recommendations, public opinion, and affordability and availability of face masks), understanding of protection effectiveness (subthemes were protection effectiveness of wearing face masks, and selection of protective measures), and past experiences. CONCLUSIONS: Individuals' decision to wear face masks was influenced by the combination of factors identified. Identification of these factors provides guidance for explaining wearing face masks in public and helps policy makers develop feasible recommendations for wearing face masks during COVID-19 outbreak.

16.
Appl Microbiol Biotechnol ; 107(2-3): 651-661, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: covidwho-2174051

RESUMEN

Porcine deltacoronavirus (PDCoV) is an emerging swine enteropathogenic coronavirus that caused diarrhea and/or vomiting in neonatal piglets worldwide. Coronaviruses nucleocapsid (N) protein is the most conserved structural protein for viral replication and possesses good antigenicity. In this study, three monoclonal antibodies (mAbs), 3B4, 4D3, and 4E3 identified as subclass IgG2aκ were prepared using the lymphocytic hybridoma technology against PDCoV N protein. Furthermore, the B-cell epitope recognized by mAb 4D3 was mapped by dozens of overlapping truncated recombinant proteins based on the western blotting. The polypeptide 28QFRGNGVPLNSAIKPVE44 (EP-4D3) in the N-terminal of PDCoV N protein was identified as the minimal linear epitope for binding mAb 4D3. And the EP-4D3 epitope's amino acid sequence homology study revealed that PDCoV strains are substantially conserved, with the exception of the Alanine43 substitution Valine43 in the China lineage, the Early China lineage, and the Thailand, Vietnam, and Laos lineage. The epitope sequences shared high similarity (94.1%) with porcine coronavirus HKU15-155 (PorCoV HKU15), Asian leopard cats coronavirus (ALCCoV), sparrow coronavirus HKU17 (SpCoV HKU17), and sparrow deltacoronavirus. In contrast, the epitope sequences shared a very low homology (11.8 to 29.4%) with other porcine CoVs (PEDV, TGEV, PRCV, SADS-CoV, PHEV). Overall, the study will enrich the biological function of PDCoV N protein and provide foundational data for further development of diagnostic applications. KEY POINTS: • Three monoclonal antibodies against PDCoV N protein were prepared. • Discovery of a novel B-cell liner epitope (28QFRGNGVPLNSAIKPVE44) of PDCoV N protein. • The epitope EP-4D3 was conserved among PDCoV strains.


Asunto(s)
Infecciones por Coronavirus , Coronavirus , Enfermedades de los Porcinos , Porcinos , Animales , Deltacoronavirus/genética , Epítopos de Linfocito B/genética , Proteínas de la Nucleocápside/genética , Proteínas de la Nucleocápside/metabolismo , Coronavirus/genética , Infecciones por Coronavirus/veterinaria , Anticuerpos Monoclonales
17.
Front Public Health ; 10: 979063, 2022.
Artículo en Inglés | MEDLINE | ID: covidwho-2199463

RESUMEN

Introduction: SARS-CoV-2 has ravaged the world and undergone multiple mutations during the course of the COVID-19 pandemic. On 7 April 2022, an epidemic caused by SARS-CoV-2 Omicron (BA.2) variant broke out in Guangzhou, China, one of the largest transportation and logistical hubs of the country. Methods: To fast curtained the Omicron epidemic, based on the routine surveillance on the risk population of SARS-CoV-2 infection, we identify key places of the epidemic and implement enhanced control measures against Omicron. Results: Transmission characteristics of the Omicron variant were analyzed for 273 confirmed cases, and key places involved in this epidemic were fully presented. The median incubation time and the generation time were 3 days, and the reproduction number Rt was sharply increased with a peak of 4.20 within 2 days. We tried an all-out effort to tackle the epidemic in key places, and the proportion of confirmed cases increased from 61.17% at Stage 2 to 88.89% at Stage 4. Through delimited risk area management, 99 cases were found, and the cases were isolated in advance for 2.61 ± 2.76 days in a lockdown zone, 0.44 ± 1.08 days in a controlled zone, and 0.27 ± 0.62 days in a precautionary zone. People assigned with yellow code accounted for 30.32% (84/277) of confirmed COVID-19 cases, and 83.33% of them were detected positive over 3 days since code assignment. For the districts outside the epicenter, the implementation duration of NPIs was much shorter compared with the Delta epidemic last year. Conclusion: By blocking out transmission risks and adjusting measures to local epidemic conditions through the all-out effort to tackle the epidemic in key places, by delimiting risk area management, and by conducting health code management of the at-risk population, the Omicron epidemic could be contained quickly.


Asunto(s)
COVID-19 , Humanos , COVID-19/epidemiología , Control de Enfermedades Transmisibles , Pandemias , SARS-CoV-2
18.
Sci Rep ; 12(1): 21096, 2022 Dec 06.
Artículo en Inglés | MEDLINE | ID: covidwho-2151081

RESUMEN

China detected the first case of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection with Delta variant in May 2021. We assessed control strategies against this variant of concern. We constructed a robust transmission model to assess the effectiveness of interventions against the Delta variant in Guangzhou with initial quarantine/isolation, followed by social distancing. We also assessed the effectiveness of alternative strategies and that against potentially more infectious variants. The effective reproduction number (Rt) fell below 1 when the average daily number of close contacts was reduced to ≤ 7 and quarantine/isolation was implemented on average at the same day of symptom onset in Guangzhou. Simulations showed that the outbreak could still be contained when quarantine is implemented on average 1 day after symptom onset while the average daily number of close contacts was reduced to ≤ 9 per person one week after the outbreak's beginning. Early quarantine and reduction of close contacts were found to be important for containment of the outbreaks. Early implementation of quarantine/isolation along with social distancing measures could effectively suppress spread of the Delta and more infectious variants.

19.
Chinese Journal of Virology ; 37(4):900-909, 2021.
Artículo en Chino | CAB Abstracts | ID: covidwho-2145388

RESUMEN

Preliminary screening and identification of the host proteins interacting with the nucleocapsid(N)protein of the porcine deltacoronavirus(DCoV). Co-immunoprecipitation and liquid chromatography- tandem mass spectrometry were used to screen out the host proteins interacting with the N protein of the porcine DCoV. Bioinformatics analysis was carried out, and then co-immunoprecipitation was used for identification. Sodium dodecyl sulfate - polyacrylamide gel electrophoresis of the immunoprecipitation products revealed different protein bands around 40 kDa and 100 kDa. Sixty-eight host proteins interacting with the N protein of the porcine DCoV were screened by mass spectrometry. Two candidate interacting proteins(ANXA2 and TUBB2 B)were selected by analyses using the Gene Ontology, Clusters of Orthologous Groups, and Kyoto Encyclopedia of Genes and Genomes databases. After co-immunoprecipitation verification, the N protein of the porcine DCoV was found to interact with TUBB2 B. Our study provides a new direction for further exploration of the role of the N protein of the porcine DCoV in infection.

20.
Acta Pharmaceutica Sinica B ; 2022.
Artículo en Inglés | ScienceDirect | ID: covidwho-2130064

RESUMEN

Messenger RNA (mRNA) is the template for protein biosynthesis and is emerging as an essential active molecule to combat various diseases, including viral infection and cancer. Especially, mRNA-based vaccines, as a new type of vaccine, have played a leading role in fighting against the current global pandemic of COVID-19. However, the inherent drawbacks, including large size, negative charge, and instability, hinder its use as a therapeutic agent. Lipid carriers are distinguishable and promising vehicles for mRNA delivery, owning the capacity to encapsulate and deliver negatively charged drugs to the targeted tissues and release cargoes at the desired time. Here, we first summarized the structure and properties of different lipid carriers, such as liposomes, liposome-like nanoparticles, solid lipid nanoparticles, lipid-polymer hybrid nanoparticles, nanoemulsions, exosomes and lipoprotein particles, and their applications in delivering mRNA. Then, the development of lipid-based formulations as vaccine delivery systems was discussed and highlighted. Recent advancements in the mRNA vaccine of COVID-19 were emphasized. Finally, we described our future vision and perspectives in this field.

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