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The COVID-19 pandemic urgently needs therapeutic and prophylactic interventions. Here, we report the rapid identification of SARS-CoV-2-neutralizing antibodies by high-throughput single-cell RNA and VDJ sequencing of antigen-enriched B cells from 60 convalescent patients. From 8,558 antigen-binding IgG1+ clonotypes, 14 potent neutralizing antibodies were identified, with the most potent one, BD-368-2, exhibiting an IC50 of 1.2 and 15 ng/mL against pseudotyped and authentic SARS-CoV-2, respectively. BD-368-2 also displayed strong therapeutic and prophylactic efficacy in SARS-CoV-2-infected hACE2-transgenic mice. Additionally, the 3.8 Å cryo-EM structure of a neutralizing antibody in complex with the spike-ectodomain trimer revealed the antibody's epitope overlaps with the ACE2 binding site. Moreover, we demonstrated that SARS-CoV-2-neutralizing antibodies could be directly selected based on similarities of their predicted CDR3H structures to those of SARS-CoV-neutralizing antibodies. Altogether, we showed that human neutralizing antibodies could be efficiently discovered by high-throughput single B cell sequencing in response to pandemic infectious diseases.
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Anticuerpos Monoclonales/aislamiento & purificación , Anticuerpos Neutralizantes/aislamiento & purificación , Linfocitos B/inmunología , Infecciones por Coronavirus/inmunología , Neumonía Viral/inmunología , Análisis de la Célula Individual , Animales , Anticuerpos Monoclonales/administración & dosificación , Anticuerpos Monoclonales/química , Anticuerpos Monoclonales/metabolismo , Anticuerpos Neutralizantes/administración & dosificación , Anticuerpos Neutralizantes/química , Anticuerpos Neutralizantes/metabolismo , COVID-19 , Convalecencia , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Ratones , Pandemias , Análisis de Secuencia de ARN , Glicoproteína de la Espiga del Coronavirus/química , Glicoproteína de la Espiga del Coronavirus/metabolismo , Exones VDJRESUMEN
The continuing emergence of SARS-CoV-2 variants highlights the need to update COVID-19 vaccine compositions. However, immune imprinting induced by vaccination based on the ancestral (hereafter referred to as WT) strain would compromise the antibody response to Omicron-based boosters1-5. Vaccination strategies to counter immune imprinting are critically needed. Here we investigated the degree and dynamics of immune imprinting in mouse models and human cohorts, especially focusing on the role of repeated Omicron stimulation. In mice, the efficacy of single Omicron boosting is heavily limited when using variants that are antigenically distinct from WT-such as the XBB variant-and this concerning situation could be mitigated by a second Omicron booster. Similarly, in humans, repeated Omicron infections could alleviate WT vaccination-induced immune imprinting and generate broad neutralization responses in both plasma and nasal mucosa. Notably, deep mutational scanning-based epitope characterization of 781 receptor-binding domain (RBD)-targeting monoclonal antibodies isolated from repeated Omicron infection revealed that double Omicron exposure could induce a large proportion of matured Omicron-specific antibodies that have distinct RBD epitopes to WT-induced antibodies. Consequently, immune imprinting was largely mitigated, and the bias towards non-neutralizing epitopes observed in single Omicron exposures was restored. On the basis of the deep mutational scanning profiles, we identified evolution hotspots of XBB.1.5 RBD and demonstrated that these mutations could further boost the immune-evasion capability of XBB.1.5 while maintaining high ACE2-binding affinity. Our findings suggest that the WT component should be abandoned when updating COVID-19 vaccines, and individuals without prior Omicron exposure should receive two updated vaccine boosters.
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Anticuerpos Antivirales , Vacunas contra la COVID-19 , COVID-19 , Inmunización Secundaria , Memoria Inmunológica , SARS-CoV-2 , Animales , Humanos , Ratones , Anticuerpos Monoclonales/inmunología , Anticuerpos Neutralizantes/inmunología , Anticuerpos Antivirales/inmunología , COVID-19/inmunología , COVID-19/prevención & control , COVID-19/virología , Vacunas contra la COVID-19/administración & dosificación , Vacunas contra la COVID-19/inmunología , Epítopos de Linfocito B/inmunología , Memoria Inmunológica/inmunología , SARS-CoV-2/clasificación , SARS-CoV-2/genética , SARS-CoV-2/inmunología , MutaciónRESUMEN
Extreme precipitation is a considerable contributor to meteorological disasters and there is a great need to mitigate its socioeconomic effects through skilful nowcasting that has high resolution, long lead times and local details1-3. Current methods are subject to blur, dissipation, intensity or location errors, with physics-based numerical methods struggling to capture pivotal chaotic dynamics such as convective initiation4 and data-driven learning methods failing to obey intrinsic physical laws such as advective conservation5. We present NowcastNet, a nonlinear nowcasting model for extreme precipitation that unifies physical-evolution schemes and conditional-learning methods into a neural-network framework with end-to-end forecast error optimization. On the basis of radar observations from the USA and China, our model produces physically plausible precipitation nowcasts with sharp multiscale patterns over regions of 2,048 km × 2,048 km and with lead times of up to 3 h. In a systematic evaluation by 62 professional meteorologists from across China, our model ranks first in 71% of cases against the leading methods. NowcastNet provides skilful forecasts at light-to-heavy rain rates, particularly for extreme-precipitation events accompanied by advective or convective processes that were previously considered intractable.
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Continuous evolution of Omicron has led to a rapid and simultaneous emergence of numerous variants that display growth advantages over BA.5 (ref. 1). Despite their divergent evolutionary courses, mutations on their receptor-binding domain (RBD) converge on several hotspots. The driving force and destination of such sudden convergent evolution and its effect on humoral immunity remain unclear. Here we demonstrate that these convergent mutations can cause evasion of neutralizing antibody drugs and convalescent plasma, including those from BA.5 breakthrough infection, while maintaining sufficient ACE2-binding capability. BQ.1.1.10 (BQ.1.1 + Y144del), BA.4.6.3, XBB and CH.1.1 are the most antibody-evasive strains tested. To delineate the origin of the convergent evolution, we determined the escape mutation profiles and neutralization activity of monoclonal antibodies isolated from individuals who had BA.2 and BA.5 breakthrough infections2,3. Owing to humoral immune imprinting, BA.2 and especially BA.5 breakthrough infection reduced the diversity of the neutralizing antibody binding sites and increased proportions of non-neutralizing antibody clones, which, in turn, focused humoral immune pressure and promoted convergent evolution in the RBD. Moreover, we show that the convergent RBD mutations could be accurately inferred by deep mutational scanning profiles4,5, and the evolution trends of BA.2.75 and BA.5 subvariants could be well foreseen through constructed convergent pseudovirus mutants. These results suggest that current herd immunity and BA.5 vaccine boosters may not efficiently prevent the infection of Omicron convergent variants.
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Anticuerpos Antivirales , Deriva y Cambio Antigénico , COVID-19 , Evolución Molecular , Inmunidad Humoral , SARS-CoV-2 , Glicoproteína de la Espiga del Coronavirus , Humanos , Anticuerpos Monoclonales/inmunología , Anticuerpos Neutralizantes/inmunología , Anticuerpos Antivirales/inmunología , Infección Irruptiva/inmunología , Infección Irruptiva/virología , COVID-19/inmunología , COVID-19/virología , Sueroterapia para COVID-19 , SARS-CoV-2/química , SARS-CoV-2/genética , SARS-CoV-2/inmunología , Glicoproteína de la Espiga del Coronavirus/química , Glicoproteína de la Espiga del Coronavirus/genética , Glicoproteína de la Espiga del Coronavirus/inmunología , Dominios Proteicos/genética , Dominios Proteicos/inmunología , Deriva y Cambio Antigénico/inmunología , MutaciónRESUMEN
The SARS-CoV-2 B.1.1.529 (Omicron) variant contains 15 mutations of the receptor-binding domain (RBD). How Omicron evades RBD-targeted neutralizing antibodies requires immediate investigation. Here we use high-throughput yeast display screening1,2 to determine the profiles of RBD escaping mutations for 247 human anti-RBD neutralizing antibodies and show that the neutralizing antibodies can be classified by unsupervised clustering into six epitope groups (A-F)-a grouping that is highly concordant with knowledge-based structural classifications3-5. Various single mutations of Omicron can impair neutralizing antibodies of different epitope groups. Specifically, neutralizing antibodies in groups A-D, the epitopes of which overlap with the ACE2-binding motif, are largely escaped by K417N, G446S, E484A and Q493R. Antibodies in group E (for example, S309)6 and group F (for example, CR3022)7, which often exhibit broad sarbecovirus neutralizing activity, are less affected by Omicron, but a subset of neutralizing antibodies are still escaped by G339D, N440K and S371L. Furthermore, Omicron pseudovirus neutralization showed that neutralizing antibodies that sustained single mutations could also be escaped, owing to multiple synergetic mutations on their epitopes. In total, over 85% of the tested neutralizing antibodies were escaped by Omicron. With regard to neutralizing-antibody-based drugs, the neutralization potency of LY-CoV016, LY-CoV555, REGN10933, REGN10987, AZD1061, AZD8895 and BRII-196 was greatly undermined by Omicron, whereas VIR-7831 and DXP-604 still functioned at a reduced efficacy. Together, our data suggest that infection with Omicron would result in considerable humoral immune evasion, and that neutralizing antibodies targeting the sarbecovirus conserved region will remain most effective. Our results inform the development of antibody-based drugs and vaccines against Omicron and future variants.
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Anticuerpos Neutralizantes/inmunología , Anticuerpos Antivirales/inmunología , Evasión Inmune/inmunología , Pruebas de Neutralización , SARS-CoV-2/inmunología , Enzima Convertidora de Angiotensina 2/metabolismo , Anticuerpos Monoclonales/inmunología , Anticuerpos Monoclonales/uso terapéutico , Anticuerpos Neutralizantes/clasificación , Anticuerpos Antivirales/clasificación , COVID-19/inmunología , COVID-19/virología , Vacunas contra la COVID-19/inmunología , Células Cultivadas , Convalecencia , Epítopos de Linfocito B/química , Epítopos de Linfocito B/inmunología , Humanos , Sueros Inmunes/inmunología , Modelos Moleculares , Mutación , SARS-CoV-2/química , SARS-CoV-2/genética , Glicoproteína de la Espiga del Coronavirus/química , Glicoproteína de la Espiga del Coronavirus/genética , Glicoproteína de la Espiga del Coronavirus/inmunología , Glicoproteína de la Espiga del Coronavirus/metabolismoRESUMEN
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Omicron sublineages BA.2.12.1, BA.4 and BA.5 exhibit higher transmissibility than the BA.2 lineage1. The receptor binding and immune-evasion capability of these recently emerged variants require immediate investigation. Here, coupled with structural comparisons of the spike proteins, we show that BA.2.12.1, BA.4 and BA.5 (BA.4 and BA.5 are hereafter referred collectively to as BA.4/BA.5) exhibit similar binding affinities to BA.2 for the angiotensin-converting enzyme 2 (ACE2) receptor. Of note, BA.2.12.1 and BA.4/BA.5 display increased evasion of neutralizing antibodies compared with BA.2 against plasma from triple-vaccinated individuals or from individuals who developed a BA.1 infection after vaccination. To delineate the underlying antibody-evasion mechanism, we determined the escape mutation profiles2, epitope distribution3 and Omicron-neutralization efficiency of 1,640 neutralizing antibodies directed against the receptor-binding domain of the viral spike protein, including 614 antibodies isolated from people who had recovered from BA.1 infection. BA.1 infection after vaccination predominantly recalls humoral immune memory directed against ancestral (hereafter referred to as wild-type (WT)) SARS-CoV-2 spike protein. The resulting elicited antibodies could neutralize both WT SARS-CoV-2 and BA.1 and are enriched on epitopes on spike that do not bind ACE2. However, most of these cross-reactive neutralizing antibodies are evaded by spike mutants L452Q, L452R and F486V. BA.1 infection can also induce new clones of BA.1-specific antibodies that potently neutralize BA.1. Nevertheless, these neutralizing antibodies are largely evaded by BA.2 and BA.4/BA.5 owing to D405N and F486V mutations, and react weakly to pre-Omicron variants, exhibiting narrow neutralization breadths. The therapeutic neutralizing antibodies bebtelovimab4 and cilgavimab5 can effectively neutralize BA.2.12.1 and BA.4/BA.5, whereas the S371F, D405N and R408S mutations undermine most broadly sarbecovirus-neutralizing antibodies. 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.
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Anticuerpos Antivirales , Deriva y Cambio Antigénico , COVID-19 , Epítopos de Linfocito B , Tolerancia Inmunológica , Mutación , SARS-CoV-2 , Enzima Convertidora de Angiotensina 2/metabolismo , Anticuerpos Monoclonales/inmunología , Anticuerpos Neutralizantes/inmunología , Anticuerpos Antivirales/inmunología , Deriva y Cambio Antigénico/genética , Deriva y Cambio Antigénico/inmunología , COVID-19/inmunología , COVID-19/transmisión , COVID-19/virología , Vacunas contra la COVID-19/inmunología , Epítopos de Linfocito B/química , Epítopos de Linfocito B/genética , Epítopos de Linfocito B/inmunología , Humanos , Inmunidad Humoral , Inmunización Secundaria , Pruebas de Neutralización , SARS-CoV-2/clasificación , SARS-CoV-2/genética , SARS-CoV-2/inmunología , SARS-CoV-2/metabolismo , Glicoproteína de la Espiga del Coronavirus/genética , Glicoproteína de la Espiga del Coronavirus/inmunología , Glicoproteína de la Espiga del Coronavirus/metabolismoRESUMEN
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) XBB lineages have achieved dominance worldwide and keep on evolving. Convergent evolution of XBB lineages on the receptor-binding domain (RBD) L455F and F456L is observed, resulting in variants with substantial growth advantages, such as EG.5, FL.1.5.1, XBB.1.5.70, and HK.3. Here, we show that neutralizing antibody (NAb) evasion drives the convergent evolution of F456L, while the epistatic shift caused by F456L enables the subsequent convergence of L455F through ACE2 binding enhancement and further immune evasion. L455F and F456L evade RBD-targeting Class 1 public NAbs, reducing the neutralization efficacy of XBB breakthrough infection (BTI) and reinfection convalescent plasma. Importantly, L455F single substitution significantly dampens receptor binding; however, the combination of L455F and F456L forms an adjacent residue flipping, which leads to enhanced NAbs resistance and ACE2 binding affinity. The perturbed receptor-binding mode leads to the exceptional ACE2 binding and NAb evasion, as revealed by structural analyses. Our results indicate the evolution flexibility contributed by epistasis cannot be underestimated, and the evolution potential of SARS-CoV-2 RBD remains high.
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Enzima Convertidora de Angiotensina 2 , COVID-19 , Humanos , Enzima Convertidora de Angiotensina 2/genética , SARS-CoV-2/genética , COVID-19/genética , Sueroterapia para COVID-19 , Anticuerpos NeutralizantesRESUMEN
The mpox outbreak has subdued with fewer reported cases at the present in high-income countries. It is known that mpox virus (MPXV) infection has been epidemic for more than 50 years in African countries. The ancestral MPXV strain has changed into multiple clades, indicating the ongoing evolution of MPXV, which reflects the historical neglect of mpox in Africa, especially after smallpox eradication, and bestows the danger of more severe mpox epidemics in the future. It is thus imperative to continue the development of mpox diagnostics and treatments so we can be prepared in the event of a new mpox epidemic. In this study, we have developed an MPXV detection tool that leverages the recombinase-aid amplification assay by integrating lateral flow strips (RAA-LF) and one-step sample DNA preparation, with visible readout, no need of laboratory instrument, and ready for field deployment. The detection limit reaches 10 copies per reaction. The performance of our RAA-FL assay in diagnosing mpox clinical samples is on par with that of the quantitative polymerase chain reaction (PCR) assay. Taken together, we have developed a point-of-care RAA-LF method of high accuracy and sensitivity, readily deployable for field detection of MPXV. This diagnostic tool is expected to improve and accelerate field- and self-diagnosis, allow timely isolation and treatment, reduce the spread of MPXV, thus effectively mitigate MPXV outbreak in the future.
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Monkeypox virus , Mpox , Humanos , África , Bioensayo , Brotes de EnfermedadesRESUMEN
Epithelial-mesenchymal transition (EMT) is a crucial biologic process for breast cancer metastasis, and inhibition of EMT could be an effective approach to suppress metastatic potential of mammary cancer. High expression of low-density lipoprotein receptor-related protein 6 (LRP6) is usually observed in breast carcinoma and predicts poor prognosis. In the present study, we investigated whether chlorogenic acid (CA) can inhibit the EMT of breast cancer cells and underlying molecular mechanism. We found that CA treatment transformed MCF-7 cell morphology from spindle shape (mesenchymal phenotype) to spherical shape (epithelial phenotype). CA clearly increased epithelial biomarkers' expression (E-cadherin and ZO-1) but decreased mesenchymal proteins' expression (ZEB1, N-cadherin, vimentin, snail, and slug). In addition, CA attenuated MMP-2 and MMP-9 activities and inhibited cell migration and invasion. CA downregulated the expression of LRP6 in MCF-7 cells. Knockdown LRP6 with siRNA repressed cell mobility and invasion, wheras overexpression of LRP6 promoted EMT and antagonized the EMT inhibitory effect of CA on MCF-7 cells. Furthermore, CA directly interacted with Wnt/ß-catenin signaling coreceptor LRP6 and reduced LRP6, p-LRP6, and ß-catenin expression levels in MCF-7 cells. In vivo study revealed that CA notably reduced tumor volume and tumor weight. CA decreased the expression of LRP6, N-cadherin, ZEB1, vimentin, MMP2, MMP9, and increased the expression of E-cadherin and ZO-1. In conclusion, CA inhibited EMT and invasion of breast cancer by targeting LRP6. SIGNIFICANCE STATEMENT: CA, the familiar polyphenol compound in traditional Chinese medicine, repressed EMT and weakened cellular mobility and invasion in MCF-7 cells. The mechanism studies demonstrated that CA could inhibit EMT and invasion of MCF-7 cells via targeting LRP6. Additionally, CA restrained tumor growth and xenograft tumor EMT in vivo. The EMT inhibitory property of CA warrants further studies of CA as a drug candidate for the therapy of metastatic breast carcinoma.
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Neoplasias de la Mama , beta Catenina , Humanos , Femenino , beta Catenina/metabolismo , beta Catenina/farmacología , Vimentina/farmacología , Ácido Clorogénico/farmacología , Ácido Clorogénico/uso terapéutico , Línea Celular Tumoral , Transición Epitelial-Mesenquimal/genética , Proteína-6 Relacionada a Receptor de Lipoproteína de Baja Densidad , Neoplasias de la Mama/genética , Movimiento Celular , CadherinasRESUMEN
HH-120, a recently developed IgM-like ACE2 fusion protein with broad-spectrum neutralizing activity against all ACE2-utilizing coronaviruses, has been developed as a nasal spray for use as an early treatment agent to reduce disease progression and airborne transmission. The objective of this study was to evaluate the safety and efficacy of the HH-120 nasal spray in SARS-CoV-2-infected subjects. Eligible symptomatic or asymptomatic SARS-CoV-2-infected participants were enrolled in a single-arm trial to receive the HH-120 nasal spray for no longer than 6 days or until viral clearance at a single hospital between August 3 and October 7, 2022. An external control was built from real-world data of SARS-CoV-2-infected subjects contemporaneously hospitalized in the same hospital using a propensity score matching (PSM) method. After PSM, 65 participants in the HH-120 group and 103 subjects with comparable baseline characteristics in the external control group were identified. The viral clearance time was significantly shorter in participants receiving the HH-120 nasal spray than that in subjects of the control group (median 8 days vs. 10 days, p < 0.001); the difference was more prominent in those subgroup subjects with higher baseline viral load (median 7.5 days vs. 10.5 days, p < 0.001). The incidence of treatment-emergent adverse events and treatment-related adverse events of HH-120 group were 35.1% (27/77) and 3.9% (3/77), respectively. All the adverse events observed were mild, being of CTCAE grade 1 or 2, and transient. The HH-120 nasal spray showed a favorable safety profile and promising antiviral efficacy in SARS-CoV-2-infected subjects. The results from this study warrant further assessment of the efficacy and safety of the HH-120 nasal spray in large-scale randomized controlled clinical trials.
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Enzima Convertidora de Angiotensina 2 , COVID-19 , Humanos , Rociadores Nasales , SARS-CoV-2 , Estudios de Cohortes , Puntaje de Propensión , Inmunoglobulina MRESUMEN
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Omicron harbors more than 30 mutations of the spike protein and exhibits substantial immune evasion. Although previous study indicated that BNT162b2 messenger RNA vaccine induces potent cross-clade pan-sarbecovirus neutralizing antibodies in survivors of the infection by SARS-CoV-1, the neutralization activity and Fc-mediated effector functions of these cross-reactive antibodies elicited in SARS-CoV-1 survivors to Omicron subvariants still remain largely unknown. In this study, the neutralization activity and Fc-mediated effector functions of antibodies boosted by a third dose vaccination were characterized in SARS-CoV-1 convalescents and healthy individuals. Potent cross-clade broadly neutralizing antibodies were observed in SARS-CoV-1 survivors who received a three-dose vaccination regimen consisting of two priming doses of CoronaVac followed by one booster dose of the protein subunit vaccine ZF2001. However, the induced antibodies exhibited both reduced neutralization and impaired Fc effector functions targeting multiple Omicron subvariants. Importantly, the data also support the notion that immune imprints resulted from SARS-CoV-1 infection may exacerbate the impairment of neutralization activity and Fc-mediated effector functions to Omicron subvariants and provided invaluable information to vaccination strategy in future.
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Vacuna BNT162 , Coronavirus Relacionado al Síndrome Respiratorio Agudo Severo , Humanos , Vacunas de Subunidad , SARS-CoV-2 , Sobrevivientes , Anticuerpos Neutralizantes , Anticuerpos AntiviralesRESUMEN
HH-120, an IgM-like angiotensin converting enzyme 2 (ACE2) fusion protein, has been developed as a nasal spray against Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and is currently undergoing human trials. HH-120 nasal spray was assessed for postexposure prophylaxis (PEP) in two investigator-initiated (NS01 and NS02) trials with different risk levels of SARS-CoV-2 exposure. NS01 enrolled family caregiver participants who had continuous contacts with laboratory-confirmed index cases; NS02 enrolled participants who had general contacts (Part 1) or close contacts (Part 2) with index cases. The primary endpoints were safety and laboratory-confirmed and/or symptomatic SARS-CoV-2 infection. In NS01 trial (14 participants), the SARS-CoV-2 infection rates were 25% in the HH-120 group and 83.3% in the external control group (relative risk reduction [RRR]: 70.0%). In NS02-Part 1 (193 participants), the infection rates were 4% (HH-120) versus 11.3% (placebo), symptomatic infection rates were 0.8% versus 3.5%, hence with a RRR of 64.6% and 77.1%, respectively. In Part 2 (76 participants), the infection rates were 17.1% (HH-120) versus 30.4% (placebo), symptomatic infection rates were 7.5% versus 27.3%, with a RRR of 43.8% and 72.5%, respectively. No HH-120-related serious adverse effects were observed. The HH-120 nasal spray used as PEP was safe and effective in preventing laboratory-confirmed and symptomatic SARS-CoV-2 infection.
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Enzima Convertidora de Angiotensina 2 , COVID-19 , Proteínas Recombinantes de Fusión , Humanos , Enzima Convertidora de Angiotensina 2/uso terapéutico , COVID-19/prevención & control , Inmunoglobulina M , Rociadores Nasales , SARS-CoV-2 , Proteínas Recombinantes de Fusión/uso terapéutico , Profilaxis PosexposiciónRESUMEN
OBJECTIVES: To describe a high-sensitivity SARS-CoV-2 antigen test that is based on the fully automated light-initiated chemiluminescent immunoassay (LiCA®), and to validate its analytical characteristics and clinical agreement on detecting SARS-CoV-2 infection against the reference molecular test. METHODS: Analytical performance was validated and detection limits were determined using different types of nucleocapsid protein samples. 798-pair anterior nasal swab specimens were collected from hospitalized patients and asymptomatic screening individuals. Agreement between LiCA® antigen and real-time reverse transcription polymerase chain reaction (rRT-PCR) was evaluated. RESULTS: Repeatability and within-lab precision were 1.6-2.3%. The C5â¼C95 interval was -5.1-4.6% away from C50. Detection limits in average (SD) were 325 (±141) U/mL on the national reference panel, 0.07 (±0.04) TCID50/mL on active viral cultures, 0.27 (±0.09) pg/mL on recombinant nucleocapsid proteins and 1.07 (±1.01) TCID50/mL on inactivated viral suspensions, respectively. LiCA detected a median of 374-fold (IQR 137-643) lower levels of the viral antigen than comparative rapid tests. As reference to the rRT-PCR method, overall sensitivity and specificity were determined to be 97.5% (91.4-99.7%) and 99.9% (99.2-100%), respectively. Total agreement between both methods was 99.6% (98.7-99.9%) with Cohen's kappa 0.98 (0.96-1). A positive detection rate of 100% (95.4-100%) was obtained as Ct≤37.8. CONCLUSIONS: The LiCA® system provides an exceptionally high-sensitivity and fully automated platform for the detection of the SARS-CoV-2 antigen in nasal swabs. The assay may have high potential use for large-scale population screening and surveillance of COVID-19 as an alternative to the rRT-PCR test.
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COVID-19 , SARS-CoV-2 , Humanos , COVID-19/diagnóstico , Prueba de COVID-19/métodos , Sensibilidad y Especificidad , Proteínas de la Nucleocápside/genética , Reacción en Cadena en Tiempo Real de la Polimerasa/métodos , Inmunoensayo/métodosRESUMEN
OBJECTIVE: The outbreak of coronavirus disease (COVID-19) coincided with the season of influenza A pneumonia, a common respiratory infectious disease. Therefore, this study compared ultrasonography and computed tomography (CT) for the diagnosis of the two diseases. METHODS: Patients with COVID-19 or influenza A infection hospitalized at our hospital were included. The patients were examined by ultrasonography every day. The CT examination results within 1 day before and after the day of the highest ultrasonography score were selected as the controls. The similarities and differences between the ultrasonography and CT results in the two groups were compared. RESULTS: There was no difference between the ultrasonography and CT scores (P = .307) for COVID-19, while there was a difference between ultrasonography and CT scores for influenza A pneumonia (P = .024). The ultrasonography score for COVID-19 was higher than that for influenza A pneumonia (P = .000), but there was no difference between the CT scores (P = .830). For both diseases, there was no difference in ultrasonography and CT scores between the left and right lungs; there were differences between the CT scores of the upper and middle lobes, as well as between the upper and lower lobes of the lungs; however, there was no difference between the lower and middle lobes of the lungs. CONCLUSION: Ultrasonography is equivalent to the gold standard CT for diagnosing and monitoring the progression of COVID-19. Because of its convenience, ultrasonography has important application value. Furthermore, the diagnostic value of ultrasonography for COVID-19 is higher than that for influenza A pneumonia.
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COVID-19 , Gripe Humana , Neumonía , Humanos , COVID-19/diagnóstico por imagen , SARS-CoV-2 , Gripe Humana/diagnóstico por imagen , Neumonía/diagnóstico por imagen , Pulmón/diagnóstico por imagen , Tomografía Computarizada por Rayos X/métodos , Ultrasonografía , Estudios Retrospectivos , Prueba de COVID-19RESUMEN
BACKGROUND Mass burn casualties impose an enormous burden on triage systems. The triage capacity of the Braden Scale for detecting injury severity has not been evaluated in mass burn casualties. MATERIAL AND METHODS The New Injury Severity Score (NISS) was used to dichotomize the injury severity of patients. The Braden Scale and other potentially indicative measurement tools were evaluated using univariate analysis and multivariate logistic regression. The relationships between the Braden Scale and other continuous variables with injury severity were further explored by correlation analysis and fitted with regression models. Receiver operating characteristic (ROC) curve analysis was used to validate triage capacity and compare prognostic accuracy. RESULTS A total of 160 hospitalized patients were included in our study; 37 were severely injured, and 123 were not. Injury severity was independently associated with the Numerical Rating Scale (adjusted OR, 1.816; 95% CI, 1.035-3.187) and Braden Scale (adjusted OR, 0.693; 95% CI, 0.564-0.851). The ROC curve of the fitted quadratic model of the Braden Scale was 0.896 (0.840-0.953), and the cut-off value was 17. The sensitivity was 81.08% (64.29-91.44%) and the specificity was 82.93% (74.85-88.89%). Comparison of ROC curves demonstrated an infinitesimal difference between the Braden Scale and NISS for predicting 30-day hospital discharge (Z=0.291, P=0.771) and Intensive Care Unit admission (Z=2.016, P=0.044). CONCLUSIONS The Braden Scale is a suitable triage tool for predicting injury severity and forecasting disability-related outcomes in patients affected by mass burn casualty incidents.
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Quemaduras/diagnóstico , Puntaje de Gravedad del Traumatismo , Incidentes con Víctimas en Masa/estadística & datos numéricos , Triaje/métodos , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pronóstico , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Adulto JovenRESUMEN
BACKGROUND: This study aimed to investigate the relationship between echocardiography results and lung ultrasound score (LUS) in coronavirus disease 2019 (COVID-19) pneumonia patients and evaluate the impact of the combined application of these techniques in the evaluation of COVID-19 pneumonia. METHODS: Hospitalized COVID-19 pneumonia patients who underwent daily lung ultrasound and echocardiography were included in this study. Patients with tricuspid regurgitation within three days of admission were enrolled. Moreover, the correlation and differences between their pulmonary artery pressure (PAP) and LUS on days 3, 8, and 13 were analyzed. The inner diameter of the pulmonary artery root as well as the size of the atria and ventricles were also considered. RESULTS: The PAP on days 3, 8, and 13 of hospitalization was positively correlated with the LUS (r = 0.448, p = 0.003; r = 0.738, p < 0.001; r = 0.325, p = 0.036, respectively). On day 8, the values of both PAP and LUS were higher than on days 3 and 13 (p < 0.01). Similarly, PAP and LUS were significantly increased in 92.9% (39/42) and 90.5% (38/42) of patients, respectively, and at least one of these two values was positive in 97.6% (41/42) of cases. The inner diameters of the right atrium, right ventricle, and pulmonary artery also differed significantly from their corresponding values on days 3 and 13 (p < 0.05). CONCLUSIONS: PAP is positively correlated with LUS in COVID-19 pneumonia. The two values could be combined for a more precise assessment of disease progression and recovery status.
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COVID-19 , Neumonía , Ecocardiografía , Humanos , Pulmón/diagnóstico por imagen , Proyectos Piloto , Neumonía/diagnóstico por imagen , SARS-CoV-2 , UltrasonografíaRESUMEN
BACKGROUND: Infectious disease outbreaks such as the COVID-19 (coronavirus disease 2019) pandemic call for rapid response and complete screening of the suspected community population to identify potential carriers of pathogens. Central laboratories rely on time-consuming sample collection methods that are rarely available in resource-limited settings. METHODS: We present a highly automated and fully integrated mobile laboratory for fast deployment in response to infectious disease outbreaks. The mobile laboratory was equipped with a 6-axis robot arm for automated oropharyngeal swab specimen collection; virus in the collected specimen was inactivated rapidly using an infrared heating module. Nucleic acid extraction and nested isothermal amplification were performed by a "sample in, answer out" laboratory-on-a-chip system, and the result was automatically reported by the onboard information platform. Each module was evaluated using pseudovirus or clinical samples. RESULTS: The mobile laboratory was stand-alone and self-sustaining and capable of on-site specimen collection, inactivation, analysis, and reporting. The automated sampling robot arm achieved sampling efficiency comparable to manual collection. The collected samples were inactivated in as short as 12 min with efficiency comparable to a water bath without damage to nucleic acid integrity. The limit of detection of the integrated microfluidic nucleic acid analyzer reached 150 copies/mL within 45 min. Clinical evaluation of the onboard microfluidic nucleic acid analyzer demonstrated good consistency with reverse transcription quantitative PCR with a κ coefficient of 0.979. CONCLUSIONS: The mobile laboratory provides a promising solution for fast deployment of medical diagnostic resources at critical junctions of infectious disease outbreaks and facilitates local containment of SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) transmission.
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Prueba de Ácido Nucleico para COVID-19/métodos , COVID-19/diagnóstico , Laboratorios , Unidades Móviles de Salud , Patología Molecular/métodos , ARN Viral/análisis , Adulto , Automóviles , COVID-19/epidemiología , Prueba de Ácido Nucleico para COVID-19/instrumentación , Femenino , Humanos , Dispositivos Laboratorio en un Chip , Masculino , Técnicas Analíticas Microfluídicas/instrumentación , Técnicas Analíticas Microfluídicas/métodos , Coronavirus del Síndrome Respiratorio de Oriente Medio/química , Técnicas de Diagnóstico Molecular/instrumentación , Técnicas de Diagnóstico Molecular/métodos , Pandemias , Patología Molecular/instrumentación , Robótica , SARS-CoV-2/químicaRESUMEN
BACKGROUND: There is still no clinical evidence available to support or to oppose corticosteroid treatment for coronavirus disease 2019 (COVID-19) pneumonia. OBJECTIVE: To investigate the efficacy and safety of corticosteroid given to the hospitalized patients with COVID-19 pneumonia. METHODS: This was a prospective, multicenter, single-blind, randomized control trial. Adult patients with COVID-19 pneumonia who were admitted to the general ward were randomly assigned to either receive methylprednisolone or not for 7 days. The primary end point was the incidence of clinical deterioration 14 days after randomization. RESULTS: We terminated this trial early because the number of patients with COVID-19 pneumonia in all the centers decreased in late March. Finally, a total of 86 COVID-19 patients underwent randomization. There was no difference of the incidence of clinical deterioration between the methylprednisolone group and control group (4.8 vs. 4.8%, p = 1.000). The duration of throat viral RNA detectability in the methylprednisolone group was 11 days (interquartile range, 6-16 days), which was significantly longer than that in the control group (8 days [2-12 days], p = 0.030). There were no significant differences between the 2 groups in other secondary outcomes. Mass cytometry discovered CD3+ T cells, CD8+ T cells, and NK cells in the methylprednisolone group which were significantly lower than those in the control group after randomization (p < 0.05). CONCLUSIONS: From this prematurely closed trial, we found that the short-term early use of corticosteroid could suppress the immune cells, which may prolong severe acute respiratory syndrome coronavirus 2 shedding in patients with COVID-19 pneumonia. TRIAL REGISTRATION: ClinicalTrials.gov, NCT04273321.
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Tratamiento Farmacológico de COVID-19 , Glucocorticoides/uso terapéutico , Hospitalización , Metilprednisolona/uso terapéutico , Faringe/química , ARN Viral/aislamiento & purificación , Esparcimiento de Virus , Adulto , Anciano , Antibacterianos/uso terapéutico , Antivirales/uso terapéutico , Complejo CD3 , Linfocitos T CD8-positivos , COVID-19/sangre , COVID-19/terapia , COVID-19/transmisión , Prueba de Ácido Nucleico para COVID-19 , Progresión de la Enfermedad , Intervención Médica Temprana , Oxigenación por Membrana Extracorpórea , Femenino , Humanos , Células Asesinas Naturales , Recuento de Linfocitos , Masculino , Persona de Mediana Edad , Terapia por Inhalación de Oxígeno , Habitaciones de Pacientes , Faringe/virología , Modelos de Riesgos Proporcionales , Respiración Artificial , SARS-CoV-2 , Método Simple Ciego , Subgrupos de Linfocitos T , Linfocitos T , Factores de Tiempo , Resultado del TratamientoRESUMEN
PURPOSE: It has been reported widely on various methods of repairing scalp avulsion/defect, including anastomotic vessels for total scalp avulsion and dermal grafts (skin grafting, latissimus dorsi or anterior serratus flap, "visor flap" repair.). The long-term retrospective study, however, with large sample size remains rare; and there is no report on decision-making tree for repairing emergency scalp avulsion/defects under critical conditions. METHODS: The decision-making model is provided for surgeons to design the scalp reconstruction based on the retrospective analysis of 175 cases of scalp avulsion/scalp defect. In this 10-year retrospective study, 175 cases of the repair of scalp avulsion and scalp defects in a single center were analyzed. The clinical decision model was generated based on representative cases. RESULTS: For patients with scalp avulsion/defects, a comprehensive examination and evaluation on systemic injury and complication should be conducted first for saving lives and reducing trauma effects. To make more reasonable clinical decisions, it is also required to determine the location, size, depth of scalp defect the injury area of cranial periosteum, injury of blood vessel or other adjacent organs, and whether the scalp can be reused. Meanwhile, it is necessary to evaluate whether the patient can tolerate long-term anastomotic vascular surgery according to the vital signs and physical status. CONCLUSION: The primary treatment goal is to decrease traumatic effects and save patient's life while repairing and reconstructing scalp avulsions and scalp defects. In addition, it is necessary to comprehensively consider the anatomical, functional and cosmetic characteristics of scalp, surgical equipment, team technical skillsets and patient's own pursuit to optimize a reasonable surgical solution.
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Toma de Decisiones Clínicas , Lesiones por Desenguantamiento/cirugía , Servicios Médicos de Urgencia/métodos , Modelos Teóricos , Procedimientos de Cirugía Plástica/métodos , Cuero Cabelludo/lesiones , Cuero Cabelludo/cirugía , Anastomosis Quirúrgica , Femenino , Colgajos Tisulares Libres/irrigación sanguínea , Humanos , Masculino , Terapia de Presión Negativa para Heridas , Estudios Retrospectivos , Trasplante de Piel/métodos , Procedimientos Quirúrgicos VascularesRESUMEN
A major unanswered question in the current global coronavirus disease 2019 (COVID-19) outbreak is why severe disease develops in a small minority of infected individuals. In the current article, we report that homozygosity for the C allele of rs12252 in the interferon-induced transmembrane protein 3 (IFITM3) gene is associated with more severe disease in an age-dependent manner. This supports a role for IFITM3 in disease pathogenesis and the opportunity for early targeted intervention in at-risk individuals.