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1.
J Immunol ; 212(7): 1081-1093, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38380993

RESUMO

Arthritis causes Fos-like 2 (Fosl2) inactivation, and various immune cells contribute to its pathogenesis. However, little is known about the role of Fosl2 in hematopoiesis and the possible pathological role of Fosl2 inactivation in the hematopoietic system in arthritis. In this study, we show that Fosl2 maintains hematopoietic stem cell (HSC) quiescence and differentiation while controlling the inflammatory response via macrophages. Fosl2-specific deletion in the hematopoietic system caused the expansion of HSCs and myeloid cell growth while affecting erythroid and B cell differentiation. Fosl2 inactivation enhanced macrophage M1 polarization and stimulated proinflammatory cytokines and myeloid growth factors, skewing HSCs toward myeloid cell differentiation, similar to hematopoietic alterations in arthritic mice. Loss of Fosl2 mediated by Vav-iCre also displays an unexpected deletion in embryonic erythro-myeloid progenitor-derived osteoclasts, leading to osteopetrosis and anemia. The reduced bone marrow cellularity in Vav-iCreFosl2f/f mice is a consequence of the reduced bone marrow space in osteopetrotic mice rather than a direct role of Fosl2 in hematopoiesis. Thus, Fosl2 is indispensable for erythro-myeloid progenitor-derived osteoclasts to maintain the medullary cavity to ensure normal hematopoiesis. These findings improve our understanding of the pathogenesis of bone-destructive diseases and provide important implications for developing therapeutic approaches for these diseases.


Assuntos
Antígeno 2 Relacionado a Fos , Células-Tronco Hematopoéticas , Osteopetrose , Animais , Camundongos , Artrite/patologia , Transtornos da Insuficiência da Medula Óssea/patologia , Diferenciação Celular , Hematopoese/genética , Osteopetrose/genética , Osteopetrose/patologia , Antígeno 2 Relacionado a Fos/genética
2.
BMC Plant Biol ; 24(1): 494, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38831264

RESUMO

BACKGROUND ACMELLA RADICANS: (Jacquin) R.K. Jansen is a new invasive species record for Yunnan Province, China. Native to Central America, it has also been recently recorded invading other parts of Asia. To prevent this weed from becoming a serious issue, an assessment of its ecological impacts and potential distribution is needed. We predicted the potential distribution of A. radicans in China using the MaxEnt model and its ecological impacts on local plant communities and soil nutrients were explored. RESULTS: Simulated training using model parameters produced an area under curve value of 0.974, providing a high degree of confidence in model predictions. Environmental variables with the greatest predictive power were precipitation of wettest month, isothermality, topsoil TEB (total exchangeable bases), and precipitation seasonality, with a cumulative contribution of more than 72.70% and a cumulative permutation importance of more than 69.20%. The predicted potential suitable area of A. radicans in China is concentrated in the southern region. Projected areas of A. radicans ranked as high and moderately suitable comprised 5425 and 26,338 km2, accounting for 0.06 and 0.27% of the Chinese mainland area, respectively. Over the 5 years of monitoring, the population density of A. radicans increased while at the same time the population density and importance values of most other plant species declined markedly. Community species richness, diversity, and evenness values significantly declined. Soil organic matter, total N, total P, available N, and available P concentrations decreased significantly with increasing plant cover of A. radicans, whereas pH, total K and available K increased. CONCLUSION: Our study was the first to show that A. radicans is predicted to expand its range in China and may profoundly affect plant communities, species diversity, and the soil environment. Early warning and monitoring of A. radicans must be pursued with greater vigilance in southern China to prevent its further spread.


Assuntos
Espécies Introduzidas , China , Solo/química , Ecossistema
3.
Molecules ; 29(13)2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38998989

RESUMO

Cholesteric liquid crystal microcapsules (CLCMs) are used to improve the stability of liquid crystals while ensuring their stimulus response performance and versatility, with representative applications such as sensing, anticounterfeiting, and smart fabrics. However, the reflectivity and angular anisotropy decrease because of the anchoring effect of the polymer shell matrix, and the influence of particle size on this has not been thoroughly studied. In this study, the effect of synthesis technology on microcapsule particle size was investigated using a complex coalescence method, and the effect of particle size on the reflectivity and angular anisotropy of CLCMs was investigated in detail. A particle size of approximately 66 µm with polyvinyl alcohol (PVA, 1:1) exhibited a relative reflectivity of 16.6% and a bandwidth of 20 nm, as well as a narrow particle size distribution of 22 µm. The thermosetting of microcapsules coated with PVA was adjusted and systematically investigated by controlling the mass ratio. The optimized mass ratio of microcapsules (66 µm) to PVA was 2:1, increasing the relative reflectivity from 16.6% (1:1) to 32.0% (2:1) because of both the higher CLCM content and the matching between the birefringence of the gelatin-arabic shell system and PVA. Furthermore, color based on Bragg reflections was observed in the CLCM-coated ortho-axis and blue-shifted off-axis, and this change was correlated with the CLCM particle size. Such materials are promising for anticounterfeiting and color-based applications with bright colors and angular anisotropy in reflection.

4.
Small ; 19(40): e2301545, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37287408

RESUMO

Practical applications of lithium-sulfur (Li-S) batteries have been hindered by sluggish reaction kinetics and severe capacity decay during charge-discharge cycling due to the notorious shuttle effect of polysulfide and the unfavored deposition and dissolution of Li2 S. Herein, to address these issues, a double-defect engineering strategy is developed for preparing Co-doped FeP catalyst containing P vacancies on MXene, which effectively improves the bidirectional redox of Li2 S. Mechanism analysis indicates that P vacancy accelerates Li2 S nucleation via increased unsaturated sites, and Co doping generates local electric field to reduce the reaction energy barrier and accelerate Li2 S dissolution. MXene provides highly conductive channels for electron transport, and effectively captures polysulfide. The double-defect catalyst enables an impressive reversible specific capacity of 1297.9 mAh g-1 at 0.2 C, and excellent rate capability of 726.5 mAh g-1 at 4 C. Remarkably, it demonstrates excellent cycling stability with capacity retention of 533.3 mAh g-1 after 500 cycles at 2 C. The results can unlock the double-defect engineering of vacancy induction and heteroatomic doping towards practical Li-S batteries.

5.
Angew Chem Int Ed Engl ; 62(41): e202310419, 2023 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-37615859

RESUMO

Zeolites with uniform micropores are important shape-selective catalysts. However, the external acid sites of zeolites have a negative impact on shape-selective catalysis, and the microporosity may lead to serious diffusion limitation. Herein, we report on the direct synthesis of hierarchical hollow STW-type zeolite single crystals with a siliceous exterior. In an alkalinous fluoride medium, the nucleation of highly siliceous STW zeolites takes place first, and the nanocrystals are preferentially aligned on the outer surface of the gel agglomerates to grow into single crystalline shells upon crystallization. The lagged crystallization of the internal Al-rich amorphous gels onto the inner surface of nanocrystalline zeolite shells leads to the formation of hollow cavities in the core of the zeolite crystals. The hollow zeolite single crystals possess a low-to-high aluminum gradient from the surface to the core, resulting in an intrinsic inert external surface, and exhibit superior catalytic performance in toluene methylation reactions.

6.
Phys Chem Chem Phys ; 24(45): 27915-27922, 2022 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-36367389

RESUMO

Although the d-band correlations within metastable rare-earth ferrites (ReFe2O4) enable charge ordering transition functionalities beyond conventional semiconductors, their material synthesis yet requires a reducing atmosphere that is toxic and explosive. Herein, we demonstrate a reactive spark plasma sintering (RSPS) strategy to effectively synthesize metastable ReFe2O4 (Re = Er, Tm, Yb, Lu) simply in coarse vacuum within a greatly shortened reaction period. High flexibility is gained in adjusting their rare-earth composition and thereby the charge ordering transition temperature within 218-330 K. Assisted by the temperature-dependent near edge X-ray absorption fine structure (NEXAFS) analysis, an elevation in the Fe3+/Fe2+ orbital configuration within ReFe2O4 was observed compared to previous reports, and it is consistent with their higher Mott temperature and activation energy observed in their electrical transportations. This work elucidates stabilization of the metastable phase (e.g., ReFe2O4) via the non-equilibrium processes of RSPS beyond the thermodynamic restrictions.

7.
BMC Microbiol ; 20(1): 270, 2020 08 28.
Artigo em Inglês | MEDLINE | ID: mdl-32859152

RESUMO

BACKGROUND: The experimental materials were a 60-year-old tea tree (Camellia sinensis cv. Shu Cha Zao; SCZ) (the mother plant) and 1-year-old and 20-year-old plants of SCZ that originated as mother plant cuttings. The aim of this study was to use high-throughput sequencing to study the spatial and dynamic distribution of endophytic fungi in different leaf niches (upper leaves, middle leaves, lower leaves) and rhizosphere soil on tea plants of different ages in the same garden. RESULTS: Ascomycota (83.77%), Basidiomycota (11.71%), and Zygomycota (3.45%) were the dominant fungal phyla in all samples. Cladosporium (12.73%), Zymoseptoria (9.18%), and Strelitziana (13.11%) were the dominant genera in the leaf. Alpha diversity analysis revealed that endophytic communities in leaves differed from those in rhizosphere soil and different leaf niches had similar fungal diversity. Shannon's indices and NMDS analysis indicated significant differences in fungal diversity and composition among the SCZ trees of different ages (p ≤ 0.01). The abundance of Cladosporium and Zymoseptoria decreased with increasing SCZ age, whereas the abundance of Strelitziana increased. CONCLUSIONS: The results illustrate variation in endophytic fungi among different niches on tea plants of different ages. The distribution of endophytic fungi in leaves of C. sinensis shows spatiotemporal variation.


Assuntos
Camellia sinensis/microbiologia , Endófitos/fisiologia , Fungos , Biodiversidade , Camellia sinensis/crescimento & desenvolvimento , Endófitos/genética , Fungos/genética , Sequenciamento de Nucleotídeos em Larga Escala , Folhas de Planta/microbiologia , Rizosfera , Microbiologia do Solo , Análise Espaço-Temporal
8.
PLoS Comput Biol ; 14(10): e1006518, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30359364

RESUMO

Although a standard reinforcement learning model can capture many aspects of reward-seeking behaviors, it may not be practical for modeling human natural behaviors because of the richness of dynamic environments and limitations in cognitive resources. We propose a modular reinforcement learning model that addresses these factors. Based on this model, a modular inverse reinforcement learning algorithm is developed to estimate both the rewards and discount factors from human behavioral data, which allows predictions of human navigation behaviors in virtual reality with high accuracy across different subjects and with different tasks. Complex human navigation trajectories in novel environments can be reproduced by an artificial agent that is based on the modular model. This model provides a strategy for estimating the subjective value of actions and how they influence sensory-motor decisions in natural behavior.


Assuntos
Tomada de Decisões/fisiologia , Desempenho Psicomotor/fisiologia , Reforço Psicológico , Algoritmos , Biologia Computacional , Humanos , Modelos Biológicos , Recompensa
9.
Sensors (Basel) ; 19(13)2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-31266169

RESUMO

In order to obtain accurate and optimized navigation sensor information, it is necessary to study information fusion and fault diagnosis with high reliability, high precision and high autonomy, and then to propose a rapid and accurate intelligent decision-making scheme based on multi-source and heterogeneous navigation information. In view of the existing fault-tolerant navigation federated filter structure, the method of assuming the reference system (inertial navigation system) to be fault-free and then diagnosing the measuring sensor fault is generally adopted. Considering that the structure of the filter can't detect and isolate the faults of the inertial navigation system, the performance of the MEMS inertial navigation system declines due to complex environments resulting from vibrations and temperature changes; additionally, external interference may lead to the direct failure of the MEMS inertial device. Therefore, this paper studies a fault-tolerant navigation method based on a no-reference system. For the sensor sub-system of a custom micro air vehicle (MAV), a fault detection method based on a reference-free system is proposed. Based on the fault type analysis, some improvements have been made to the existing residual chi-square detection method, and an interactive residual fault detection method with distributed states is proposed. On this basis, aiming at the characteristics of a reference-free system, the weight distribution scheme of the reference system and the tested systems are studied, and a self-regulation filter fusion and fault detection method based on reference-free system is designed.

11.
Appetite ; 101: 23-30, 2016 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-26850309

RESUMO

Hispanic children are disproportionally affected by obesity-related risk of metabolic disease. We used the structural equation modeling to examine the associations between specific diet and physical activity (PA) behaviors at home and Hispanic children's metabolic health. A total of 187 Hispanic children and their parents from an urban community in Wisconsin participated in the study. Exposure variables included, children's daily intake of sugar-sweetened beverages (SSB) and PA; home availability of SSB and PA areas/equipment; and parents' intake of SSB and PA, assessed through self-administered questionnaires. Outcome variables for children's metabolic health included, measured anthropometrics; cardiovascular fitness assessed using the Progressive Aerobic Cardiovascular Endurance Run (PACER); and insulin resistance determined with the homeostasis model assessment of insulin resistance (HOMAIR). We found that children's daily intake of SSB was positively associated with BMI z-score, which in turn, was positively associated with HOMAIR (P < 0.05). Specific diet behaviors at home associated with children's intake of SSB, included home availability of SSB, which mediated the association between parents' and children's intake of SSB (P < 0.05). Children's PA was positively associated with PACER z-score, which in turn, was inversely associated with HOMAIR (P < 0.05). Specific PA behaviors at home associated with children's PA, included home availability of PA areas/equipment, which mediated the association between parents' and children's PA (P < 0.05). The structural equation model indices suggested a satisfactory model fit (Chi-square, X(2) = 53.1, comparative fix index = 0.92, root-mean-squared error associated = 0.04). The findings confirm the need for interventions at the family level that promotes healthier home environments by targeting poor diet and low levels of PA in all family members.


Assuntos
Dieta , Meio Ambiente , Teste de Esforço , Hispânico ou Latino , Resistência à Insulina , Adolescente , Bebidas/análise , Índice de Massa Corporal , Criança , Estudos Transversais , Ingestão de Energia , Exercício Físico , Características da Família , Feminino , Humanos , Masculino , Adoçantes Calóricos/administração & dosagem , Adoçantes Calóricos/análise , Obesidade , Relações Pais-Filho , Pais/psicologia , Inquéritos e Questionários , Wisconsin
12.
ACS Appl Mater Interfaces ; 16(28): 36354-36362, 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-38955841

RESUMO

Sodium-ion batteries (SIBs), owing to their abundant resources and cost-effectiveness, have garnered considerable interest in the realm of large-scale energy storage. The properties of cathode materials profoundly affect the cycle stability and specific capacity of batteries. Herein, a series of Cu-doped spherical P2-type Na0.7Fe0.23-xCuxMn0.77O2 (x = 0, 0.05, 0.09, and 0.14, x-NFCMO) was fabricated using a convenient hydrothermal method. The successful doping of Cu efficaciously mitigated the Jahn-Teller effect, augmented the electrical conductivity of the material, and diminished the resistance to charge transfer. The distinctive spherical structure remained stable and withstood considerable volumetric strain, thereby improving the cyclic stability of the material. The optimized 0.09-NFCMO cathode exhibited a high specific capacity of 168.6 mAh g-1 at 100 mA g-1, a superior rate capability (90.9 mAh g-1 at 2000 mA g-1), and a good cycling stability. This unique structure design and doping approach provides new insights into the design of advanced electrode materials for sodium-ion batteries.

13.
J Phys Chem Lett ; : 7716-7723, 2024 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-39041920

RESUMO

The multiple magneto-/electrical quantum transitions discovered with d-band correlated metastable perovskite oxides, such as rare-earth nickelate (ReNiO3), enable applications in artificial intelligence and multifunctional sensors. Nevertheless, to date such investigation merely focuses on ReNiO3 with light or middle rare-earth composition, while the analogous explorations toward heavy rare-earth (ReHNiO3, ReH after Gd) are impeded by their ineffective material synthesis relying on GPa pressure. Herein, for the first time we synthesized the powder of ReHNiO3 in grams/batch with ∼1000 times lower pressure and ∼300 °C lower temperature in comparison to the previous ∼101 milligram/batch results, assisted by their eutectic precipitation and heterogeneous growth within alkali-metal halide molten salt at MPa oxygen pressures. Further in situ characterizations under high pressures within a diamond anvil cell reveal a distinguishing pressure predominated bad metal transport within the nonequilibrium state of ReHNiO3 showing high-pressure sensitivity up to 10 GPa, and the temperature dependences in electrical transportations are effectively frozen.

14.
Thyroid ; 34(7): 912-919, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38666684

RESUMO

Objective: To clarify the association between levothyroxine (LT4) treatment and various adverse pregnancy outcomes in pregnant women with thyrotropin (TSH) levels ranging between 2.5 and 10.0 mIU/L in the first trimester, stratified according to thyroid peroxidase antibody (TPOAb) positivity and TSH level. Methods: This retrospective analysis of retrospectively and prospectively collected cohort data included Chinese pregnant women with TSH levels of 2.5-10 mIU/L and normal free thyroxine levels (11.8-18.4 pmol/L) in the first trimester. All participants were followed up until the completion of pregnancy, and information on LT4 treatment, pregnancy complications, and pregnancy outcomes was recorded. A 1:1 nearest-neighbor propensity score matching (PSM) between the LT4-treated and - untreated groups with a caliper distance of 0.02 was performed using a multivariable logistic regression model. Multivariable-adjusted modified Poisson regression was used to estimate the relative risk (RR) and 95% confidence interval (CI) of LT4 treatment for adverse pregnancy outcomes. Subgroup analyses were also performed in four subgroups simultaneously stratified by TPOAb status (negative or positive) and TSH levels (2.5-4.0 mIU/L as high-normal group and 4.0-10.0 mIU/L as SCH group). The study was registered in the Chinese Clinical Trial Registry (ChiCTR2100047394). Results: Among the 4,370 pregnant women in the study, 1,342 received LT4 treatment and 3,028 did not. The 1:1 PSM yielded 668 pairs of individuals and revealed that LT4 treatment was significantly associated with a decreased risk of pregnancy loss (RR = 0.528, 95% CI: 0.344-0.812) and an increased risk of small-for-gestational-age infants (RR = 1.595, 95% CI: 1.023-2.485). Subgroup analyses suggested that the above effects of LT4 treatment were mainly from TPOAb-negative participants. LT4 treatment was associated with an increased risk of preterm birth (RR = 2.214, 95% CI: 1.016-4.825) in TPOAb-positive pregnant women with high-normal TSH levels. Conclusion: LT4 treatment was significantly associated with a lower risk of pregnancy loss and a higher risk of small-for-gestational-age infants in pregnant women with TSH levels of 2.5-10 mIU/L. An increased risk of preterm birth was observed in the LT4-treated group among TPOAb-positive participants with TSH levels of 2.5-4.0 mIU/L.


Assuntos
Hipotireoidismo , Complicações na Gravidez , Resultado da Gravidez , Pontuação de Propensão , Tireotropina , Tiroxina , Humanos , Feminino , Gravidez , Tiroxina/uso terapêutico , Tiroxina/sangue , Tireotropina/sangue , Adulto , Estudos Retrospectivos , Complicações na Gravidez/tratamento farmacológico , Complicações na Gravidez/sangue , Hipotireoidismo/sangue , Hipotireoidismo/tratamento farmacológico , China , Primeiro Trimestre da Gravidez , Autoanticorpos/sangue , Iodeto Peroxidase/imunologia , Nascimento Prematuro
15.
Vaccines (Basel) ; 12(5)2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38793715

RESUMO

The rapid mutation of SARS-CoV-2 has led to multiple rounds of large-scale breakthrough infection and reinfection worldwide. However, the dynamic changes of humoral and cellular immunity responses to several subvariants after infection remain unclear. In our study, a 6-month longitudinal immune response evaluation was conducted on 118 sera and 50 PBMC samples from 49 healthy individuals who experienced BA.5/BF.7/XBB breakthrough infection or BA.5/BF.7-XBB reinfection. By studying antibody response, memory B cell, and IFN-γ secreting CD4+/CD8+ T cell response to several SARS-CoV-2 variants, we observed that each component of immune response exhibited distinct kinetics. Either BA.5/BF.7/XBB breakthrough infection or BA.5/BF.7-XBB reinfection induces relatively high level of binding and neutralizing antibody titers against Omicron subvariants at an early time point, which rapidly decreases over time. Most of the individuals at 6 months post-breakthrough infection completely lost their neutralizing activities against BQ.1.1, CH.1.1, BA.2.86, JN.1 and XBB subvariants. Individuals with BA.5/BF.7-XBB reinfection exhibit immune imprinting shifting and recall pre-existing BA.5/BF.7 neutralization antibodies. In the BA.5 breakthrough infection group, the frequency of BA.5 and XBB.1.16-RBD specific memory B cells, resting memory B cells, and intermediate memory B cells gradually increased over time. On the other hand, the frequency of IFN-γ secreting CD4+/CD8+ T cells induced by WT/BA.5/XBB.1.16 spike trimer remains stable over time. Overall, our research indicates that individuals with breakthrough infection have rapidly declining antibody levels but have a relatively stable cellular immunity that can provide some degree of protection from future exposure to new antigens.

16.
J Agric Food Chem ; 72(29): 16334-16346, 2024 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-38994810

RESUMO

Boletus aereus Fr. ex Bull. stands out as a delectable edible mushroom with high nutritional and medicinal values, featuring polysaccharides as its primary nutrient composition. In our continuous exploration of its beneficial substances, a novel polysaccharide (BAPN-1) with a molecular weight of 2279 kDa was prepared. It was identified as a glucan with a backbone composed of the residues →4)-α-Glcp-(1→ and →4,6)-α-Glcp-(1→ connected in a proportion of 5:1 and a ß-Glcp-(1→ side residue attached at C6 of the →4,6)-α-Glcp-(1→ residue. Biologically, BAPN-1 exhibited broad-spectrum antiproliferative activities against various NHL cells, including HuT-78, OCI-LY1, OCI-LY18, Jurkat, RL, and Karpas-299, with IC50 values of 0.73, 1.21, 3.18, 1.52, 3.34, and 4.25 mg/mL, respectively. Additionally, BAPN-1 significantly induced cell cycle arrest in the G2/M phase and caused apoptosis of NHL cells. Mechanistically, bulk RNA sequencing and Western blot analysis revealed that BAPN-1 could upregulate cyclin B1 and enhance cleaved caspase-9 expression through the inhibition of FGFR3 and RAF-MEK-ERK signaling pathways. This work supports the improved utilization of B. aereus in high-value health products.


Assuntos
Antineoplásicos , Apoptose , Proliferação de Células , Linfoma não Hodgkin , Polissacarídeos , Humanos , Proliferação de Células/efeitos dos fármacos , Linhagem Celular Tumoral , Apoptose/efeitos dos fármacos , Antineoplásicos/farmacologia , Antineoplásicos/química , Linfoma não Hodgkin/tratamento farmacológico , Polissacarídeos/química , Polissacarídeos/farmacologia , Polissacarídeos/isolamento & purificação , Peso Molecular , Basidiomycota/química
17.
Cell Host Microbe ; 32(1): 25-34.e5, 2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-38029742

RESUMO

Emerging SARS-CoV-2 sub-lineages like XBB.1.5, XBB.1.16, EG.5, HK.3 (FLip), and XBB.2.3 and the variant BA.2.86 have recently been identified. Understanding the efficacy of current vaccines on these emerging variants is critical. We evaluate the serum neutralization activities of participants who received COVID-19 inactivated vaccine (CoronaVac), those who received the recently approved tetravalent protein vaccine (SCTV01E), or those who had contracted a breakthrough infection with BA.5/BF.7/XBB virus. Neutralization profiles against a broad panel of 30 sub-lineages reveal that BQ.1.1, CH.1.1, and all the XBB sub-lineages exhibit heightened resistance to neutralization compared to previous variants. However, despite their extra mutations, BA.2.86 and the emerging XBB sub-lineages do not demonstrate significantly increased resistance to neutralization over XBB.1.5. Encouragingly, the SCTV01E booster consistently induces higher neutralizing titers against all these variants than breakthrough infection does. Cellular immunity assays also show that the SCTV01E booster elicits a higher frequency of virus-specific memory B cells. Our findings support the development of multivalent vaccines to combat future variants.


Assuntos
Infecções Irruptivas , Vacinas contra COVID-19 , COVID-19 , Imunização Secundária , Humanos , COVID-19/prevenção & controle , SARS-CoV-2/genética , Anticorpos Neutralizantes , Anticorpos Antivirais
18.
Cell Discov ; 10(1): 14, 2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38320990

RESUMO

The current SARS-CoV-2 variants strikingly evade all authorized monoclonal antibodies and threaten the efficacy of serum-neutralizing activity elicited by vaccination or prior infection, urging the need to develop antivirals against SARS-CoV-2 and related sarbecoviruses. Here, we identified both potent and broadly neutralizing antibodies from a five-dose vaccinated donor who exhibited cross-reactive serum-neutralizing activity against diverse coronaviruses. Through single B-cell sorting and sequencing followed by a tailor-made computational pipeline, we successfully selected 86 antibodies with potential cross-neutralizing ability from 684 antibody sequences. Among them, PW5-570 potently neutralized all SARS-CoV-2 variants that arose prior to Omicron BA.5, and the other three could broadly neutralize all current SARS-CoV-2 variants of concern, SARS-CoV and their related sarbecoviruses (Pangolin-GD, RaTG13, WIV-1, and SHC014). Cryo-EM analysis demonstrates that these antibodies have diverse neutralization mechanisms, such as disassembling spike trimers, or binding to RBM or SD1 to affect ACE2 binding. In addition, prophylactic administration of these antibodies significantly protects nasal turbinate and lung infections against BA.1, XBB.1, and SARS-CoV viral challenge in golden Syrian hamsters, respectively. Importantly, post-exposure treatment with PW5-5 and PW5-535 also markedly protects against XBB.1 challenge in these models. This study reveals the potential utility of computational process to assist screening cross-reactive antibodies, as well as the potency of vaccine-induced broadly neutralizing antibodies against current SARS-CoV-2 variants and related sarbecoviruses, offering promising avenues for the development of broad therapeutic antibody drugs.

19.
ACS Appl Mater Interfaces ; 15(42): 49223-49232, 2023 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-37838949

RESUMO

Currently, severe shuttle effects and sluggish conversion kinetics are the main obstacles to the advancement of lithium-sulfur (Li-S) batteries. Modification of the battery separator by a catalyst is a promising approach to tackle these problems, but simultaneously obtaining rich catalytic active sites, high conductivity, and remarkable stability remains a great challenge. Herein, a flower-like MXene/MoS2/SnS@C heterostructure as the functional intercalation of Li-S batteries was prepared for accelerating the synergistic adsorption-electrocatalysis of sulfur conversion. The MXene skeleton constructs a three-dimensional conductive network that anchors polysulfides and enhances charge transfer. Meanwhile, the MoS2/SnS has rich active sites for accelerating polysulfide conversion, leading to excellent electrochemical performances. A battery with MXene/MoS2/SnS@C displays an extraordinary capacity of 836.1 mAh g-1 over 200 cycles at 0.5C and demonstrates a remarkable cycling stability with a capacity attenuation of approximately 0.051% per cycle during 1000 cycles at 2C. When the sulfur loading reaches 5.1 mg cm-2, the capacity still maintains 722.4 mAh g-1 over 50 cycles. This research proposes a novel strategy to design stable catalysts for Li-S batteries with an extended lifespan.

20.
Micromachines (Basel) ; 14(5)2023 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-37241593

RESUMO

In order to remove noise generated during the accelerometer calibration process, an accelerometer denoising method based on empirical mode decomposition (EMD) and time-frequency peak filtering (TFPF) is proposed in this paper. Firstly, a new design of the accelerometer structure is introduced and analyzed by finite element analysis software. Then, an algorithm combining EMD and TFPF is proposed for the first time to deal with the noise of the accelerometer calibration process. Specific steps taken are to remove the intrinsic mode function (IMF) component of the high frequency band after the EMD decomposition, and then to use the TFPF algorithm to process the IMF component of the medium frequency band; meanwhile, the IMF component of the low frequency band is reserved, and finally the signal is reconstructed. The reconstruction results show that the algorithm can effectively suppress the random noise generated during the calibration process. The results of spectrum analysis show that EMD + TFPF can effectively protect the characteristics of the original signal and that the error can be controlled within 0.5%. Finally, Allan variance is used to analyze the results of the three methods to verify the filtering effect. The results show that the filtering effect of EMD + TFPF is the most obvious, being 97.4% higher than the original data.

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