RESUMEN
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
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
The search for new phases is an important direction in materials science. The phase transition of sulfides results in significant changes in catalytic performance, such as MoS2 and WS2. Cubic pentlandite [cPn, (Fe, Ni)9S8] can be a functional material in batteries, solar cells, and catalytic fields. However, no report about the material properties of other phases of pentlandite exists. In this study, the unit-cell parameters of a new phase of pentlandite, sulfur-vacancy enriched hexagonal pentlandite (hPn), and the phase boundary between cPn and hPn are determined for the first time. Compared to cPn, the hPn shows a high coordination number, more sulfur vacancies, and high conductivity, which result in significantly higher hydrogen evolution performance of hPn than that of cPn and make the non-nano rock catalyst hPn superior to other most known nanosulfide catalysts. The increase of sulfur vacancies during phase transition provides a new approach to designing functional materials.
RESUMEN
Three dsRNA segments were detected in Fusarium pseudograminearum strain CF14029, a pathogen causing Fusarium crown rot in China. Characterization and sequence analysis confirmed that these dsRNA sequences originated from the same virus. The viral genome consists of three dsRNA segments: dsRNA1 (3,560 nt in length), encoding an RNA-dependent RNA polymerase (RdRp), dsRNA2 (2,544 nt in length), encoding a hypothetical protein, and dsRNA3 (2,478 nt in length), encoding a putative coat protein (CP). Phylogenetic analysis based on the RdRp and CP amino acid sequences revealed a high degree of similarity of this virus to members of the genus Alternavirus, family Alternaviridae, isolated from other Fusarium fungi. As a novel member of the genus Alternavirus, this virus was provisionally named "Fusarium pseudograminearum alternavirus 1" (FpgAV1). Like other alternaviruses found in Fusarium species, the positive-sense strand of each genomic dsRNA of FpgAV1 possesses a poly(A) tail and a distinctive 5'-terminal octamer sequence (5'-GCT GTG TG-3'). This is the first report of the genomic sequence of an alternavirus identified in F. pseudograminearum.
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Fusarium , Fusarium/genética , Triticum/microbiología , Filogenia , Genoma Viral , ARN Bicatenario/genética , ARN Polimerasa Dependiente del ARN/genética , Enfermedades de las Plantas/microbiologíaRESUMEN
Anesthetic-induced developmental neurotoxicity (AIDN) can arise due to various factors, among which aberrant nerve cell death is a prominent risk factor. Animal studies have reported that repeated or prolonged anesthetic exposure can cause significant neuroapoptosis in the developing brain. Lately, non-apoptotic programmed cell deaths (PCDs), characterized by inflammation and oxidative stress, have gained increasing attention. Substantial evidence suggests that non-apoptotic PCDs are essential for neuronal cell death in AIDN compared to apoptosis. This article examines relevant publications in the PubMed database until April 2024. Only original articles in English that investigated the potential manifestations of non-apoptotic PCD in AIDN were analysed. Specifically, it investigates necroptosis, pyroptosis, ferroptosis, and parthanatos, elucidating the signaling mechanisms associated with each form. Furthermore, this study explores the potential relevance of these non-apoptotic PCDs pathways to the pathological mechanisms underlying AIDN, drawing upon their distinctive characteristics. Despite the considerable challenges involved in translating fundamental scientific knowledge into clinical therapeutic interventions, this comprehensive review offers a theoretical foundation for developing innovative preventive and treatment strategies targeting non-apoptotic PCDs in the context of AIDN.
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Anestésicos , Apoptosis , Síndromes de Neurotoxicidad , Humanos , Síndromes de Neurotoxicidad/patología , Síndromes de Neurotoxicidad/etiología , Animales , Anestésicos/efectos adversos , Anestésicos/toxicidad , Anestésicos/farmacología , Apoptosis/efectos de los fármacos , Neuronas/efectos de los fármacos , Neuronas/patología , Neuronas/metabolismo , Piroptosis/efectos de los fármacos , Estrés Oxidativo/efectos de los fármacos , Necroptosis/efectos de los fármacos , Encéfalo/efectos de los fármacos , Encéfalo/patología , Encéfalo/crecimiento & desarrollo , Ferroptosis/efectos de los fármacos , Transducción de Señal/efectos de los fármacosRESUMEN
OBJECTIVE: This study aimed to evaluate the cost-utility of the addition of vericiguat for treating chronic heart failure (CHF) in China from the healthcare payer's perspective. METHODS: A Markov model was built to estimate the cost and utility of treating CHF using vericiguat plus standard treatment (vericiguat group) vs. standard treatment alone (standard treatment group). The clinical parameters (mortality of cardiovascular and hospitalization rate of HF) were calculated according to the VICTORIA clinical trial. The HF cost and utility data were obtained from the literature published in China. One-way sensitivity analysis and probability sensitivity analysis were performed. RESULTS: According to the 13-year model, vericiguat was more expensive (155599.07 CNY vs. 259396.83 CNY) and more effective (4.41 QALYs vs. 4.54 QALYs). The incremental cost-utility ratio (ICUR) was 802389.27 CNY per QALY. One-way sensitivity analysis revealed that cardiovascular mortality in the two groups was the parameter that had the greatest impact on the results. The GDP per capita in 2022 in China was 85,700 CNY. The probability sensitivity analysis (PSA) showed that the probability of vericiguat being cost-effective was only 41.7% at the willingness-to-pay (WTP) threshold of 3 times GDP per capita (257,100 CNY). CONCLUSIONS: In China, the treatment of CHF with vericiguat is not cost-effective. The drug price could decrease to 145.8 CNY, which could be considered cost-effective.
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Análisis Costo-Beneficio , Insuficiencia Cardíaca , Cadenas de Markov , Pirimidinas , Volumen Sistólico , Humanos , Insuficiencia Cardíaca/tratamiento farmacológico , Insuficiencia Cardíaca/mortalidad , Insuficiencia Cardíaca/economía , China , Pirimidinas/uso terapéutico , Pirimidinas/economía , Enfermedad Crónica/tratamiento farmacológico , Quimioterapia Combinada , Años de Vida Ajustados por Calidad de Vida , Masculino , Femenino , Compuestos Heterocíclicos con 2 AnillosRESUMEN
Cyclobutrifluram (TYMIRIUM® technology), a new succinate dehydrogenase inhibitor (SDHI) fungicide, is currently being registered by SYNGENTA for controlling Fusarium crown rot (FCR) of wheat in China. The application of 15 or 30 g of active ingredient/100 kg seed of cyclobutrifluram significantly reduced pre-emergence damping-off, discoloration on the stem base and formation of whiteheads caused by FCR. The EC50 values of cyclobutrifluram for 60 isolates of F. pseudograminearum, 30 isolates of F. asiaticum and 30 isolates of F. graminearum ranged from 0.016 to 0.142 mg L-1, 0.010 to 0.041 mg L-1 and 0.012 to 0.059 mg L-1, respectively. One hundred and seven cyclobutrifluram-resistant (CR) mutants were obtained from three Fusarium species isolates, with ten types of mutations identified in Sdh genes. Three Fusarium species isolates exhibited similar resistance mechanisms, with the most prevalent mutations, SdhC1A83V and SdhC1R86K, accounting for 61.68% of mutants. The CR mutants possessed comparable or slightly impaired fitness compared to the corresponding parental isolates. The CR mutants carrying FpSdhBH248Y/Q/D exhibited increased sensitivity to fluopyram. An overall moderate risk of resistance development in three Fusarium species was recommended for cyclobutrifluram.
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Fusarium , Fusarium/genética , Triticum , Enfermedades de las Plantas/prevención & control , Mutación , Ácido SuccínicoRESUMEN
Fusarium asiaticum is a destructive phytopathogenic fungus that causes Fusarium head blight of wheat (FHB), leading to serious yield and economic losses to cereal crops worldwide. Our previous studies indicated that target-site mutations (K216R/E, S217P/L, or E420K/G/D) of Type I myosin FaMyo5 conferred high resistance to phenamacril. Here, we first constructed one sensitive strain H1S and three point mutation resistant strains HA, HC and H1R. Then we conducted comparative transcriptome analysis of these F. asiaticum strains after 1 and 10 µg·mL-1 phenamacril treatment. Results indicated that 2135 genes were differentially expressed (DEGs) among the sensitive and resistant strains. The DEGs encoding ammonium transporter MEP1/MEP2, nitrate reductase, copper amine oxidase 1, 4-aminobutyrate aminotransferase, amino-acid permease inda1, succinate-semialdehyde dehydrogenase, 2, 3-dihydroxybenzoic acid decarboxylase, etc., were significantly up-regulated in all the phenamacril-resistant strains. Compared to the control group, a total of 1778 and 2097 DEGs were identified in these strains after 1 and 10 µg·mL-1 phenamacril treatment, respectively. These DEGs involved in 4-aminobutyrate aminotransferase, chitin synthase 1, multiprotein-bridging factor 1, transcriptional regulatory protein pro-1, amino-acid permease inda1, ATP-dependent RNA helicase DED1, acetyl-coenzyme A synthetase, sarcoplasmic/endoplasmic reticulum calcium ATPase 2, etc., showed significantly down-regulated expression in phenamacril-sensitive strain but not in resistant strains after phenamacril treatment. In addition, cyanide hydratase, mating-type protein MAT-1, putative purine nucleoside permease, plasma membrane protein yro2, etc., showed significantly co-down-regulated expression in all the strains after phenamacril treatment. Taken together, This study provides deep insights into the resistance regulation mechanism and the inhibitory effect of fungicide phenamacril and these new annotated proteins or enzymes are worth for the discovery of new fungicide targets.
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Farmacorresistencia Fúngica , Fungicidas Industriales , Fusarium , Fusarium/efectos de los fármacos , Fusarium/genética , Fungicidas Industriales/farmacología , Farmacorresistencia Fúngica/genética , Perfilación de la Expresión Génica , Transcriptoma/efectos de los fármacos , Regulación Fúngica de la Expresión Génica/efectos de los fármacos , Enfermedades de las Plantas/microbiología , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismoRESUMEN
Fusarium crown rot (FCR), caused by Fusarium pseudograminearum, significantly impacts wheat yield and quality in China's Huanghuai region. The rapid F. pseudograminearum epidemic and FCR outbreak within a decade remain unexplained. In this study, two high-quality, chromosome-level genomes of F. pseudograminearum strains producing 3-acetyl-deoxynivalenol (3AcDON) and 15-acetyl-deoxynivalenol (15AcDON) toxins were assembled. Additionally, 38 related strains were resequenced. Genomic differences such as single nucleotide polymorphisms (SNPs), insertions/deletions (indels), and structural variations (SVs) among F. pseudograminearum strains were analyzed. The whole-genome SNP locus-based population classification mirrored the toxin chemotype (3AcDON and 15AcDON)-based classification, indicating the presence of genes associated with the trichothecene toxin gene cluster. Further analysis of differential SNP, indel, and SV loci between the 3AcDON and 15AcDON populations revealed a predominant connection to secondary metabolite synthesis genes. Notably, the majority of the secondary metabolite biosynthesis gene cluster loci were located in SNP-dense genomic regions, suggesting high mutability and a possible contribution to F. pseudograminearum population structure and environmental adaptability. This study provides insightful perspectives on the distribution and evolution of F. pseudograminearum and for forecasting the spread of wheat FCR, thereby aiding in the development of preventive measures and control strategies.
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Fusarium , Genoma Fúngico , Enfermedades de las Plantas , Polimorfismo de Nucleótido Simple , Metabolismo Secundario , Tricotecenos , Triticum , Fusarium/genética , Triticum/microbiología , Enfermedades de las Plantas/microbiología , Tricotecenos/metabolismo , China , Metabolismo Secundario/genética , Micotoxinas/genéticaRESUMEN
BACKGROUND: While previous research has established that resilience is affected by various factors, these studies have primarily focussed on individual variables associated with resilience, without providing insights into how to influence the rate of change in resilience. AIM: To examine the trajectory of resilience and identify the factors associated with changes in resilience among spousal caregivers of patients with newly diagnosed advanced cancer receiving treatment during the first 6 months. DESIGN: An observational longitudinal study. METHODS: A total of 312 spousal caregivers of patients with newly diagnosed advanced cancer were recruited from January 2022 to December 2022 in Yancheng, China. Three data collection points were established, spanning from the first month to 6 months after initial cancer treatment. A latent growth model was employed to depict the resilience trajectory at various time points. A latent growth model with time-invariant covariates was adopted to determine the factors influencing resilience trajectory. The study adhered to the STROBE checklist for proper reporting. RESULTS: Throughout the follow-up period, the participants experienced a significant increase in resilience. Gender, family income, the patient's health status, spirituality and belief in familism were significantly associated with the baseline resilience level. Moreover, family income, the patient's health status, spirituality, caregiver burden and belief in familism were significantly associated with the rate of resilience change over time. CONCLUSIONS: Spousal caregivers demonstrated a linear increase in resilience during the first 6 months after initial treatment. Meanwhile, changes in resilience were influenced by multiple factors during the early phase of cancer treatment. Thus, more attention should be paid to early identification and implementation of targeted interventions. RELEVANCE TO CLINICAL PRACTICE: Healthcare professionals should understand the change in resilience among spousal caregivers and conduct timely mental health interventions to enhance the resilience of families affected by cancer. PATIENT OR PUBLIC CONTRIBUTION: The Guidance for Reporting Involvement of Patients and the Public-Short Form reporting checklists were used to improve patient and public involvement.
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Cuidadores , Neoplasias , Resiliencia Psicológica , Humanos , Neoplasias/enfermería , Neoplasias/psicología , Masculino , Femenino , Cuidadores/psicología , Persona de Mediana Edad , Estudios Longitudinales , China , Esposos/psicología , Adulto , Anciano , Adaptación PsicológicaRESUMEN
BACKGROUND: Leakage of graphene into the environment has resulted from its increasing use. Although the impact of graphene on ecosystems is already in full swing, information regarding its impact on plants is lacking. In particular, the effects of graphene on plant growth and development vary, and basic information on the regulation of carbon and nitrogen metabolism is missing. In the current study, the way in which graphene (0, 25, 50, 100, and 200 g kg-1 ) affects maize seedlings was studied in terms of morphological and biochemical indicators. The purpose of this study was to understand better how graphene regulates plant carbon and nitrogen metabolism and to understand its interactions with leaf structure and plant growth. RESULTS: The results showed that 50 g kg-1 graphene increased plant height, stem diameter, leaf area, and dry weight; however, this was inhibited by the high level of graphene (200 g kg-1 ). Further studies indicated that different concentrations of graphene could increase leaf thickness and vascular bundle area as well as the net photosynthetic rate (Pn) of leaves; 25 and 50 g kg-1 graphene enhanced the leaves stomatal conductance (Cond), transpiration rate (Tr), intercellular carbon dioxide (Ci), and chlorophyll content. Higher concentrations decreased the above indicators. At 50 g kg-1 , graphene increased the activity of carbon/nitrogen metabolism enzymes by increasing carbon metabolites (fructose, sucrose, and soluble sugars) and soluble proteins (nitrogen metabolites). These enzymes included sucrose synthase (SS), sucrose phosphate synthase (SPS), nitrate reductase (NR), glutamine synthase (GS), and glutamate synthase (GOGAT). CONCLUSION: These results indicate that graphene can regulate the activities of key enzymes involved in carbon and nitrogen metabolism effectively and supplement nitrogen metabolism through substances produced by carbon metabolism by improving photosynthetic efficiency, thus maintaining the balance between carbon and nitrogen and promoting plant growth and development. The relationship between these indexes explained the mechanism by which graphene supported the growth of maize seedlings by enhancing photosynthetic carbon metabolism and maintaining metabolic balance. For maize seedling growth, graphene treatment with 50 g kg-1 soil is recommended. © 2023 Society of Chemical Industry.
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Grafito , Zea mays , Zea mays/metabolismo , Ecosistema , Fotosíntesis , Plantas/metabolismo , Plantones/metabolismo , Hojas de la Planta/metabolismo , Nitrógeno/metabolismoRESUMEN
BACKGROUND: Ethanol and osmotic stresses are the major limiting factors for brewing strong beer with high-gravity wort. Breeding of yeast strains with high osmotic and ethanol tolerance and studying very-high-gravity (VHG) brewing technology is of great significance for brewing strong beer. RESULTS: This study used an optimized microbial microdroplet culture (MMC) system for adaptive laboratory evolution (ALE) of Saccharomyces cerevisiae YN81 to improve its tolerance to osmotic and ethanol stress. Meanwhile, we investigated the VHG and VHG with added ethanol (VHGAE) brewing processes for the evolved mutants in brewing strong beer. The results showed that three evolved mutants were obtained; among them, the growth performance of YN81mc-8.3 under 300, 340, 380, 420 and 460 g L-1 sucrose stresses was greater than that of the other strains. The ethanol tolerance of YN81mc-8.3 was 12%, which was 20% higher than that of YN81. During strong-beer brewing in a 100 L cylindrical cone-bottom tank, the sugar utilization and ethanol yield of YN81mc-8.3 outperformed those of YN81 in both the VHG and VHGAE brewing processes. Measurement of the diacetyl concentration showed that YN81mc-8.3 had a stronger diacetyl reduction ability; in particular, the real degree of fermentation of beers brewed by YN81mc-8.3 in VHG and VHGAE brewing processes was 75.35% and 66.71%, respectively - higher than those of the two samples brewed by YN81. Meanwhile, the visual, olfactive and gustative properties of the strong beer produced by YN81mc-8.3 were better than those of the other beers. CONCLUSION: In this study, the mutant YN81mc-8.3 and the VHGAE brewing process were optimal and represented a better alternative strong-beer brewing process. © 2023 Society of Chemical Industry.
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Diacetil , Saccharomyces cerevisiae , Saccharomyces cerevisiae/genética , Fitomejoramiento , Fermentación , Etanol , CervezaRESUMEN
Since the concept of digital twin technology has been put forward, after decades of rapid development and wide application, it has not only made great achievements in many fields, but also brought broader prospects for the development of the medical field. As an important trend in the medical industry, digital twin hospitals play multiple roles by connecting physical hospitals and virtual hospitals and benefit the "patient-medical staff-hospital administrators", highlighting the immeasurable promising application of digital twin technology in smart hospitals. This review takes digital twin technology as an entry point, briefly introduces the progress of its application in various fields, focuses on the characteristics of digital twin technology, practical application cases in hospitals and their limitations, and also looks forward to its future development prospects, aiming to provide certain useful insights and guidance for the future of digital twin hospitals, and also expecting it to play an important role in changing the future of healthcare to a certain extent.
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Atención a la Salud , Humanos , Atención a la Salud/tendencias , Hospitales , Tecnología Digital/tendenciasRESUMEN
Triplex DNA switches are attractive allosteric tools for engineering smart nanodevices, but their poor triplex-forming capacity at physiological conditions limited the practical applications. To address this challenge, we proposed a low-entropy barrier design to facilitate triplex formation by introducing a hairpin duplex linker into the triplex motif, and the resulting triplex switch was termed as CTNSds. Compared to the conventional clamp-like triplex switch, CTNSds increased the triplex-forming ratio from 30 % to 91 % at pHâ 7.4 and stabilized the triple-helix structure in FBS and cell lysate. CTNSds was also less sensitive to free-energy disturbances, such as lengthening linkers or mismatches in the triple-helix stem. The CTNSds design was utilized to reversibly isolate CTCs from whole blood, achieving high capture efficiencies (>86 %) at pHâ 7.4 and release efficiencies (>80 %) at pHâ 8.0. Our approach broadens the potential applications of DNA switches-based switchable nanodevices, showing great promise in biosensing and biomedicine.
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ADN , Concentración de Iones de Hidrógeno , ADN/química , Humanos , Entropía , Conformación de Ácido Nucleico , Técnicas BiosensiblesRESUMEN
137 Cs and 90 Sr are hazardous to ecological environment and human health due to their strong radioactivity, long half-life, and high mobility. However, effective adsorption and separation of Cs+ and Sr2+ from acidic radioactive wastewater is challenging due to stability issues of material and the strong competition of protons. Herein, a K+ -activated niobium germanate (K-NGH-1) presents efficient Cs+ /Sr2+ coadsorption and highly selective Cs+ /Sr2+ separation, respectively, under different acidity conditions. In neutral solution, K-NGH-1 exhibits ultrafast adsorption kinetics and high adsorption capacity for both Cs+ and Sr2+ (qm Cs = 182.91 mg g-1 ; qm Sr = 41.62 mg g-1 ). In 1 M HNO3 solution, K-NGH-1 still possesses qm Cs of 91.40 mg g-1 for Cs+ but almost no adsorption for Sr2+ . Moreover, K-NGH-1 can effectively separate Cs+ from 1 M HNO3 solutions with excess competing Sr2+ and Mn + (Mn + = Na+ , Ca2+ , Mg2+ ) ions. Thus, efficient separation of Cs+ and Sr2+ is realized under acidic conditions. Besides, K-NGH-1 shows excellent acid and radiation resistance and recyclability. All the merits above endow K-NGH-1 with the first example of niobium germanates for radionuclides remediation. This work highlights the facile pH control approach towards bifunctional ion exchangers for efficient Cs+ /Sr2+ coadsorption and selective separation.
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This study describes a novel, neutralizing monoclonal antibody (mAb), 11D7, discovered by mouse immunization and hybridoma generation, against the parental Wuhan-Hu-1 RBD of SARS-CoV-2. We further developed this mAb into a chimeric human IgG and recombinantly expressed it in plants to produce a mAb with human-like, highly homogenous N-linked glycans that has potential to impart greater potency and safety as a therapeutic. The epitope of 11D7 was mapped by competitive binding with well-characterized mAbs, suggesting that it is a Class 4 RBD-binding mAb that binds to the RBD outside the ACE2 binding site. Of note, 11D7 maintains recognition against the B.1.1.529 (Omicron) RBD, as well neutralizing activity. We also provide evidence that this novel mAb may be useful in providing additional synergy to established antibody cocktails, such as Evusheld™ containing the antibodies tixagevimab and cilgavimab, against the Omicron variant. Taken together, 11D7 is a unique mAb that neutralizes SARS-CoV-2 through a mechanism that is not typical among developed therapeutic mAbs and by being produced in ΔXFT Nicotiana benthamiana plants, highlights the potential of plants to be an economic and safety-friendly alternative platform for generating mAbs to address the evolving SARS-CoV-2 crisis.
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COVID-19 , Terapéutica Combinada de Anticuerpos , Humanos , Animales , Ratones , SARS-CoV-2 , Anticuerpos Monoclonales , Anticuerpos Neutralizantes , Anticuerpos AntiviralesRESUMEN
BACKGROUND: Non-small cell cancer (NSCLC) patients with concomitant epidermal growth factor receptor (EGFR) and TP53 mutations have a poor prognosis with the treatment of tyrosine kinase inhibitors (TKIs), and may benefit from a combination regimen preferentially. The present study aims to compare the benefits of EGFR-TKIs and its combination with antiangiogenic drugs or chemotherapy in patients with NSCLC harboring EGFR and TP53 co-mutation in a real-life setting. METHODS: This retrospective analysis included 124 patients with advanced NSCLC having concomitant EGFR and TP53 mutations, who underwent next-generation sequencing prior to treatment. Patients were classified into the EGFR-TKI group and combination therapy group. The primary end point of this study was progression-free survival (PFS). The Kaplan-Meier (KM) curve was drawn to analyze PFS, and the differences between the groups were compared using the logarithmic rank test. Univariate and multivariate cox regression analysis was performed on the risk factors associated with survival. RESULTS: The combination group included 72 patients who received the regimen of EGFR-TKIs combined with antiangiogenic drugs or chemotherapy, while the EGFR-TKI monotherapy group included 52 patients treated with TKI only. The median PFS was significantly longer in the combination group than in the EGFR-TKI group (18.0 months; 95% confidence interval [CI]: 12.1-23.9 vs. 7.0 months; 95% CI: 6.1-7.9; p < 0.001) with greater PFS benefit in TP53 exon 4 or 7 mutations subgroup. Subgroup analysis showed a similar trend. The median duration of response was significantly longer in the combination group than in the EGFR-TKI group. Patients with 19 deletions or L858R mutations both achieved a significant PFS benefit with combination therapy versus EGFR-TKI alone. CONCLUSION: Combination therapy had a higher efficacy than EGFR-TKI alone for patients with NSCLC having concomitant EGFR and TP53 mutations. Future prospective clinical trials are needed to determine the role of combination therapy for this patient population.
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Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Humanos , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/genética , Estudios Retrospectivos , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/genética , Terapia Combinada , Receptores ErbB/genética , Inhibidores de la Angiogénesis , Proteína p53 Supresora de Tumor/genéticaRESUMEN
This study was to explore whether Streptococcus pneumoniae would form biofilms and the formative factors of biofilms, as well as the drug resistance mechanism of S. pneumoniae. In this study, a total of 150 strains of S. pneumoniae were collected from 5 local hospitals in the past two years, and the minimum inhibitory concentrations (MIC) of levofloxacin, moxifloxacin and penicillin were determined by agar double dilution method to select the drug-resistant strains. The polymerase chain reaction (PCR) amplification and sequencing were performed on specific genes of drug-resistant strains. In addition, 5 strains of S. pneumoniae with penicillin MIC ≤ 0.065 µg/mL, 0.5 µg/mL, 2 µg/mL, ≥ 4µg/mL were randomly selected, and the biofilms were cultured on two kinds of well plates for 24 hours. Finally, whether the biofilms were formed was observed. Experimental results revealed that the resistance rate of S. pneumoniae to erythromycin in this area was as high as 90.3%, and the strains that were resistant to penicillin account for only 1.5%. The amplification and sequencing experiment revealed that one (strain 1) of the strains, which was resistant to both drugs, had a GyrA mutation and ParE mutation, and strain 2 had a parC mutation. All strains generated biofilms, and the optical density (OD) value of penicillin MIC ≤ 0.065 µg/mL group (0.235 ± 0.053) was higher than that of 0.5 µg/mL group (0.192 ± 0.073) (P< 0.05) and higher than the OD value of the 4 µg/mL group (0.200 ± 0.041) (P< 0.05), showing statistically great differences. It was confirmed that the resistance rate of S. pneumoniae to erythromycin remained high, the rate of sensitivity to penicillin was relatively high, and the moxifloxacin and levofloxacin-resistant strains had appeared; S. pneumoniae mainly showed QRDR mutations in gyrA, parE, and parC; and it was confirmed that S. pneumoniae can generate biofilms in vitro.