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1.
Nature ; 609(7928): 785-792, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35922005

RESUMO

Highly pathogenic coronaviruses, including severe acute respiratory syndrome coronavirus 2 (refs. 1,2) (SARS-CoV-2), Middle East respiratory syndrome coronavirus3 (MERS-CoV) and SARS-CoV-1 (ref. 4), vary in their transmissibility and pathogenicity. However, infection by all three viruses results in substantial apoptosis in cell culture5-7 and in patient tissues8-10, suggesting a potential link between apoptosis and pathogenesis of coronaviruses. Here we show that caspase-6, a cysteine-aspartic protease of the apoptosis cascade, serves as an important host factor for efficient coronavirus replication. We demonstrate that caspase-6 cleaves coronavirus nucleocapsid proteins, generating fragments that serve as interferon antagonists, thus facilitating virus replication. Inhibition of caspase-6 substantially attenuates lung pathology and body weight loss in golden Syrian hamsters infected with SARS-CoV-2 and improves the survival of mice expressing human DPP4 that are infected with mouse-adapted MERS-CoV. Our study reveals how coronaviruses exploit a component of the host apoptosis cascade to facilitate virus replication.


Assuntos
Ácido Aspártico , Caspase 6 , Infecções por Coronavirus , Coronavirus , Cisteína , Interações Hospedeiro-Patógeno , Replicação Viral , Animais , Apoptose , Ácido Aspártico/metabolismo , Caspase 6/metabolismo , Coronavirus/crescimento & desenvolvimento , Coronavirus/patogenicidade , Infecções por Coronavirus/enzimologia , Infecções por Coronavirus/virologia , Proteínas do Nucleocapsídeo de Coronavírus/imunologia , Proteínas do Nucleocapsídeo de Coronavírus/metabolismo , Cricetinae , Cisteína/metabolismo , Dipeptidil Peptidase 4/genética , Dipeptidil Peptidase 4/metabolismo , Humanos , Interferons/antagonistas & inibidores , Interferons/imunologia , Pulmão/patologia , Mesocricetus , Camundongos , Coronavírus da Síndrome Respiratória do Oriente Médio , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave , SARS-CoV-2 , Taxa de Sobrevida , Redução de Peso
2.
Plant J ; 118(3): 802-822, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38305492

RESUMO

Floral patterns are unique to rice and contribute significantly to its reproductive success. SL1 encodes a C2H2 transcription factor that plays a critical role in flower development in rice, but the molecular mechanism regulated by it remains poorly understood. Here, we describe interactions of the SL1 with floral homeotic genes, SPW1, and DL in specifying floral organ identities and floral meristem fate. First, the sl1 spw1 double mutant exhibited a stamen-to-pistil transition similar to that of sl1, spw1, suggesting that SL1 and SPW1 may located in the same pathway regulating stamen development. Expression analysis revealed that SL1 is located upstream of SPW1 to maintain its high level of expression and that SPW1, in turn, activates the B-class genes OsMADS2 and OsMADS4 to suppress DL expression indirectly. Secondly, sl1 dl displayed a severe loss of floral meristem determinacy and produced amorphous tissues in the third/fourth whorl. Expression analysis revealed that the meristem identity gene OSH1 was ectopically expressed in sl1 dl in the fourth whorl, suggesting that SL1 and DL synergistically terminate the floral meristem fate. Another meristem identity gene, FON1, was significantly decreased in expression in sl1 background mutants, suggesting that SL1 may directly activate its expression to regulate floral meristem fate. Finally, molecular evidence supported the direct genomic binding of SL1 to SPW1 and FON1 and the subsequent activation of their expression. In conclusion, we present a model to illustrate the roles of SL1, SPW1, and DL in floral organ specification and regulation of floral meristem fate in rice.


Assuntos
Flores , Regulação da Expressão Gênica de Plantas , Meristema , Oryza , Proteínas de Plantas , Oryza/genética , Oryza/crescimento & desenvolvimento , Oryza/metabolismo , Meristema/genética , Meristema/crescimento & desenvolvimento , Meristema/metabolismo , Flores/genética , Flores/crescimento & desenvolvimento , Flores/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética , Plantas Geneticamente Modificadas , Mutação
3.
Genome Res ; 2022 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-35858749

RESUMO

Assembling RNA-seq reads into full-length transcripts is crucial in transcriptomic studies and poses computational challenges. Here we present TransMeta, a simple and robust algorithm that simultaneously assembles RNA-seq reads from multiple samples. TransMeta is designed based on the newly introduced vector-weighted splicing graph model, which enables accurate reconstruction of the consensus transcriptome via incorporating a cosine similarity-based combing strategy and a newly designed label-setting path-searching strategy. Tests on both simulated and real data sets show that TransMeta consistently outperforms PsiCLASS, StringTie2 plus its merge mode, and Scallop plus TACO, the most popular tools, in terms of precision and recall under a wide range of coverage thresholds at the meta-assembly level. Additionally, TransMeta consistently shows superior performance at the individual sample level.

4.
J Virol ; : e0112924, 2024 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-39287389

RESUMO

Because host kinases are key regulators of multiple signaling pathways in response to viral infections, we previously screened a kinase inhibitor library using rhabdomyosarcoma cells and human intestinal organoids in parallel to identify potent inhibitors against EV-A71 infection. We found that Rho-associated coiled-coil-containing protein kinase (Rock) inhibitor efficiently suppressed the EV-A71 replication and further revealed Rock1 as a novel EV-A71 host factor. In this study, subsequent analysis found that a variety of vascular endothelial growth factor receptor (VEGFR) inhibitors also had potent antiviral effects. Among the hits, Pazopanib, with a selectivity index as high as 254, which was even higher than that of Pirodavir, a potent broad-spectrum picornavirus inhibitor targeting viral capsid protein VP1, was selected for further analysis. We demonstrated that Pazopanib not only efficiently suppressed the replication of EV-A71 in a dose-dependent manner, but also exhibited broad-spectrum anti-enterovirus activity. Mechanistically, Pazopanib probably induces alterations in host cells, thereby impeding viral genome replication and transcription. Notably, VEGFR2 knockdown and overexpression suppressed and facilitated EV-A71 replication, respectively, indicating that VEGFR2 is a novel host dependency factor for EV-A71 replication. Transcriptome analysis further proved that VEGFR2 potentially plays a crucial role in combating EV-A71 infection through the TSAd-Src-PI3K-Akt pathway. These findings expand the range of potential antiviral candidates of anti-enterovirus therapeutics and suggest that VEGFR2 may be a key host factor involved in EV-A71 replication, making it a potential target for the development of anti-enterovirus therapeutics. IMPORTANCE: As the first clinical case was identified in the United States, EV-A71, a significant neurotropic enterovirus, has been a common cause of hand, foot, and mouth disease (HFMD) in infants and young children. Developing an effective antiviral agent for EV-A71 and other human enteroviruses is crucial, as these viral pathogens consistently cause outbreaks in humans. In this study, we demonstrated that multiple inhibitors against VEGFRs effectively reduced EV-A71 replication, with Pazopanib emerging as the top candidate. Furthermore, Pazopanib also attenuated the replication of other enteroviruses, including CVA10, CVB1, EV-D70, and HRV-A, displaying broad-spectrum anti-enterovirus activity. Given that Pazopanib targets various VEGFRs, we narrowed the focus to VEGFR2 using knockdown and overexpression experiments. Transcriptomic analysis suggests that Pazopanib's potential downstream targets involve the TSAd-Src-PI3K-Akt pathway. Our work may contribute to identifying targets for antiviral inhibitors and advancing treatments for human enterovirus infections.

5.
Bioinformatics ; 40(2)2024 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-38310330

RESUMO

MOTIVATION: The advancement of long-read RNA sequencing technologies leads to a bright future for transcriptome analysis, in which clustering long reads according to their gene family of origin is of great importance. However, existing de novo clustering algorithms require plenty of computing resources. RESULTS: We developed a new algorithm GeLuster for clustering long RNA-seq reads. Based on our tests on one simulated dataset and nine real datasets, GeLuster exhibited superior performance. On the tested Nanopore datasets it ran 2.9-17.5 times as fast as the second-fastest method with less than one-seventh of memory consumption, while achieving higher clustering accuracy. And on the PacBio data, GeLuster also had a similar performance. It sets the stage for large-scale transcriptome study in future. AVAILABILITY AND IMPLEMENTATION: GeLuster is freely available at https://github.com/yutingsdu/GeLuster.


Assuntos
Perfilação da Expressão Gênica , Transcriptoma , Perfilação da Expressão Gênica/métodos , Algoritmos , RNA-Seq , Análise por Conglomerados , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Software , Análise de Sequência de DNA/métodos
6.
Cancer ; 130(6): 913-926, 2024 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-38055287

RESUMO

BACKGROUND: Although the associations between genetic variations and lung cancer risk have been explored, the epigenetic consequences of DNA methylation in lung cancer development are largely unknown. Here, the genetically predicted DNA methylation markers associated with non-small cell lung cancer (NSCLC) risk by a two-stage case-control design were investigated. METHODS: The genetic prediction models for methylation levels based on genetic and methylation data of 1595 subjects from the Framingham Heart Study were established. The prediction models were applied to a fixed-effect meta-analysis of screening data sets with 27,120 NSCLC cases and 27,355 controls to identify the methylation markers, which were then replicated in independent data sets with 7844 lung cancer cases and 421,224 controls. Also performed was a multi-omics functional annotation for the identified CpGs by integrating genomics, epigenomics, and transcriptomics and investigation of the potential regulation pathways. RESULTS: Of the 29,894 CpG sites passing the quality control, 39 CpGs associated with NSCLC risk (Bonferroni-corrected p ≤ 1.67 × 10-6 ) were originally identified. Of these, 16 CpGs remained significant in the validation stage (Bonferroni-corrected p ≤ 1.28 × 10-3 ), including four novel CpGs. Multi-omics functional annotation showed nine of 16 CpGs were potentially functional biomarkers for NSCLC risk. Thirty-five genes within a 1-Mb window of 12 CpGs that might be involved in regulatory pathways of NSCLC risk were identified. CONCLUSIONS: Sixteen promising DNA methylation markers associated with NSCLC were identified. Changes of the methylation level at these CpGs might influence the development of NSCLC by regulating the expression of genes nearby. PLAIN LANGUAGE SUMMARY: The epigenetic consequences of DNA methylation in lung cancer development are still largely unknown. This study used summary data of large-scale genome-wide association studies to investigate the associations between genetically predicted levels of methylation biomarkers and non-small cell lung cancer risk at the first time. This study looked at how well larotrectinib worked in adult patients with sarcomas caused by TRK fusion proteins. These findings will provide a unique insight into the epigenetic susceptibility mechanisms of lung cancer.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Adulto , Humanos , Carcinoma Pulmonar de Células não Pequenas/genética , Metilação de DNA , Neoplasias Pulmonares/genética , Estudo de Associação Genômica Ampla , Epigênese Genética , Biomarcadores , Ilhas de CpG
7.
Anal Chem ; 96(1): 554-563, 2024 01 09.
Artigo em Inglês | MEDLINE | ID: mdl-38112727

RESUMO

The efficiency of the enzyme-free toehold-mediated strand displacement (TMSD) technique is often insufficient to detect single-nucleotide polymorphism (SNP) that possesses only single base pair mismatch discrimination. Here, we report a novel dual base pair mismatch strategy enabling TMSD biosensing for SNP detection under enzyme-free conditions when coupled with catalytic hairpin assembly (CHA) and fluorescence resonance energy transfer (FRET). The strategy is based on a competitive strand displacement reaction mechanism, affected by the thermodynamic stability originating from rationally designed dual base pair mismatch, for the specific recognition of mutant-type DNA. In particular, enzyme-free nucleic acid circuits, such as CHA, emerge as a powerful method for signal amplification. Eventually, the signal transduction of this proposed biosensor was determined by FRET between streptavidin-coated 605 nm emission quantum dots (605QDs, donor) and Cy5/biotin hybridization (acceptor, from CHA) when incubated with each other. The proposed biosensor displayed high sensitivity to the mutant target (MT) with a detection concentration down to 4.3 fM and led to high discrimination factors for all types of mismatches in multiple sequence contexts. As such, the application of this proposed biosensor to investigate mechanisms of the competitive strand displacement reaction further illustrates the versatility of our dual base pair mismatch strategy, which can be utilized for the creation of a new class of biosensors.


Assuntos
Técnicas Biossensoriais , Polimorfismo de Nucleotídeo Único , Pareamento Incorreto de Bases , Hibridização de Ácido Nucleico , Transferência Ressonante de Energia de Fluorescência , Biotina , Técnicas Biossensoriais/métodos
8.
Small ; 20(28): e2310009, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38295155

RESUMO

Magnetic soft actuators and robots have attracted considerable attention in biomedical applications due to their speedy response, programmability, and biocompatibility. Despite recent advancements, the fabrication process of magnetic actuators and the reprogramming approach of their magnetization profiles continue to pose challenges. Here, a facile fabrication strategy is reported based on arrangements and distributions of reusable magnetic pixels on silicone substrates, allowing for various magnetic actuators with customizable architectures, arbitrary magnetization profiles, and integration of microfluidic technology. This approach enables intricate configurations with decent deformability and programmability, as well as biomimetic movements involving grasping, swimming, and wriggling in response to magnetic actuation. Moreover, microfluidic functional modules are integrated for various purposes, such as on/off valve control, curvature adjustment, fluid mixing, dynamic microfluidic architecture, and liquid delivery robot. The proposed method fulfills the requirements of low-cost, rapid, and simplified preparation of magnetic actuators, since it eliminates the need to sustain pre-defined deformations during the magnetization process or to employ laser heating or other stimulation for reprogramming the magnetization profile. Consequently, it is envisioned that magnetic actuators fabricated via pixel-assembly will have broad prospects in microfluidics and biomedical applications.

9.
J Med Virol ; 96(9): e29917, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39279390

RESUMO

In the landscape of infectious diseases, human coronaviruses such as SARS-CoV, MERS-CoV, and SARS-CoV-2 pose significant threats, characterized by severe respiratory illnesses and notable resistance to conventional treatments due to their rapid evolution and the emergence of diverse variants, particularly within SARS-CoV-2. This study investigated the development of broad-spectrum coronavirus vaccines using heterodimeric RBD-Fc proteins engineered through the "Knob-into-Hole" technique. We constructed various recombinant proteins incorporating the receptor-binding domains (RBDs) of different coronaviruses. Heterodimers combining RBDs from SARS-CoV-2 with those of SARS-CoV or MERS-CoV elicited superior neutralizing responses compared to homodimeric proteins in murine models. Additionally, heterotetrameric proteins, specifically D614G_Delta/BA.1_XBB.1.5-RBD and MERS_D614G/BA.1_XBB.1.5-RBD, elicited remarkable breadth and potency in neutralizing all known SARS-CoV-2 variants, SARS-CoV, related sarbecoviruses like GD-Pangolin and WIV1, and even MERS-CoV pseudoviruses. Furthermore, these heterotetrameric proteins also demonstrated enhanced cellular immune responses. These findings underscore the potential of recombinant hetero proteins as a universal vaccine strategy against current and future coronavirus threats.


Assuntos
Anticorpos Neutralizantes , Anticorpos Antivirais , Vacinas contra COVID-19 , Coronavírus da Síndrome Respiratória do Oriente Médio , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus , Animais , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Camundongos , SARS-CoV-2/imunologia , SARS-CoV-2/genética , Glicoproteína da Espícula de Coronavírus/imunologia , Glicoproteína da Espícula de Coronavírus/genética , Glicoproteína da Espícula de Coronavírus/química , Vacinas contra COVID-19/imunologia , Humanos , Coronavírus da Síndrome Respiratória do Oriente Médio/imunologia , Coronavírus da Síndrome Respiratória do Oriente Médio/genética , Fragmentos Fc das Imunoglobulinas/imunologia , Fragmentos Fc das Imunoglobulinas/genética , Fragmentos Fc das Imunoglobulinas/química , COVID-19/prevenção & controle , COVID-19/imunologia , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave/imunologia , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave/genética , Camundongos Endogâmicos BALB C , Feminino , Domínios Proteicos , Testes de Neutralização , Proteínas Recombinantes/imunologia , Proteínas Recombinantes/genética
10.
PLoS Biol ; 19(4): e3001197, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33905408

RESUMO

Renal cell carcinoma (RCC) is responsible for most cases of the kidney cancer. Previous research showed that low serum levels of cholesterol level positively correlate with poorer RCC-specific survival outcomes. However, the underlying mechanisms and functional significance of the role of cholesterol in the development of RCC remain obscure. 3-Hydroxy-3-methylglutaryl coenzyme A reductase (HMGCR) plays a pivotal role in RCC development as it is the key rate-limiting enzyme of the cholesterol biosynthetic pathway. In this study, we demonstrated that the inhibition of HMGCR could accelerate the development of RCC tumors by lactate accumulation and angiogenesis in animal models. We identified that the inhibition of HMGCR led to an increase in glycolysis via the regulated HSP90 expression levels, thus maintaining the levels of a glycolysis rate-limiting enzyme, pyruvate kinase M2 (PKM2). Based on these findings, we reversed the HMGCR inhibition-induced tumor growth acceleration in RCC xenograft mice by suppressing glycolysis. Furthermore, the coadministration of Shikonin, a potent PKM2 inhibitor, reverted the tumor development induced by the HMGCR signaling pathway.


Assuntos
Carcinoma de Células Renais/patologia , Proteínas de Transporte/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Hidroximetilglutaril-CoA Redutases/efeitos dos fármacos , Neoplasias Renais/patologia , Proteínas de Membrana/efeitos dos fármacos , Animais , Antineoplásicos/farmacologia , Carcinoma de Células Renais/genética , Carcinoma de Células Renais/metabolismo , Proteínas de Transporte/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Feminino , Glicólise/efeitos dos fármacos , Humanos , Hidroximetilglutaril-CoA Redutases/metabolismo , Neoplasias Renais/genética , Neoplasias Renais/metabolismo , Ácido Láctico/metabolismo , Proteínas de Membrana/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Neovascularização Patológica/metabolismo , Neovascularização Patológica/patologia , Neovascularização Patológica/prevenção & controle , Estabilidade Proteica/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Hormônios Tireóideos/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto , Proteínas de Ligação a Hormônio da Tireoide
11.
Environ Sci Technol ; 58(2): 1022-1035, 2024 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-38165294

RESUMO

There is epidemiological evidence in humans that exposure to endocrine-disrupting chemicals such as bisphenol A (BPA) is tied to abnormal neuroendocrine function with both behavioral and intestinal symptoms. However, the underlying mechanism of this effect, particularly the role of gut-brain regulation, is poorly understood. We exposed zebrafish embryos to a concentration series (including environmentally relevant levels) of BPA and its analogues. The analogue bisphenol G (BPG) yielded the strongest behavioral impact on zebrafish larvae and inhibited the largest number of neurotransmitters, with an effective concentration of 0.5 µg/L, followed by bisphenol AF (BPAF) and BPA. In neurod1:EGFP transgenic zebrafish, BPG and BPAF inhibited the distribution of enteroendocrine cells (EECs), which is associated with decreased neurotransmitters level and behavioral activity. Immune staining of ace-α-tubulin suggested that BPAF inhibited vagal neural development at 50 and 500 µg/L. Single-cell RNA-Seq demonstrated that BPG disrupted the neuroendocrine system by inducing inflammatory responses in intestinal epithelial cells via TNFα-trypsin-EEC signaling. BPAF exposure activated apoptosis and inhibited neural developmental pathways in vagal neurons, consistent with immunofluorescence imaging studies. These findings show that both BPG and BPAF affect the neuroendocrine system through the gut-brain axis but by different mechanisms, revealing new insights into the modes of bisphenol-mediated neuroendocrine disruption.


Assuntos
Sistemas Neurossecretores , Fenóis , Peixe-Zebra , Animais , Humanos , Compostos Benzidrílicos/toxicidade , Encéfalo , Neurotransmissores/metabolismo
12.
Epilepsy Behav ; 151: 109636, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38232560

RESUMO

Atypical absence seizures are generalized non-convulsive seizures that often occur in children with cognitive impairment. They are common in refractory epilepsy and have been recognized as one of the hallmarks of developmental epileptic encephalopathies. Notably, pathogenic variants associated with AAS, such as GABRG2, GABRG3, SLC6A1, CACNB4, SCN8A, and SYNGAP1, are also linked to developmental epileptic encephalopathies. Atypical absences differ from typical absences in that they are frequently drug-resistant and the prognosis is dependent on the etiology or related epileptic syndromes. To improve clinicians' understanding of atypical absences and provide novel perspectives for clinical treatment, we have reviewed the electro-clinical characteristics, etiologies, treatment, and prognosis of atypical absences, with a focus on the etiology of advancements in gene variants, shedding light on potential avenues for improved clinical management.


Assuntos
Epilepsia Resistente a Medicamentos , Epilepsia Tipo Ausência , Epilepsia Generalizada , Humanos , Criança , Epilepsia Tipo Ausência/genética , Epilepsia Tipo Ausência/tratamento farmacológico , Convulsões , Proteínas Ativadoras de ras GTPase/genética , Eletroencefalografia
13.
Phys Chem Chem Phys ; 26(15): 11414-11428, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38591159

RESUMO

The ongoing evolution of the Omicron lineage of SARS-CoV-2 has led to the emergence of subvariants that pose challenges to antibody neutralization. Understanding the binding dynamics between the receptor-binding domains (RBD) of these subvariants spike and monoclonal antibodies (mAbs) is pivotal for elucidating the mechanisms of immune escape and for advancing the development of therapeutic antibodies. This study focused on the RBD regions of Omicron subvariants BA.2, BA.5, BF.7, and XBB.1.5, employing molecular dynamics simulations to unravel their binding mechanisms with a panel of six mAbs, and subsequently analyzing the origins of immune escape from energetic and structural perspectives. Our results indicated that the antibody LY-COV1404 maintained binding affinities across all studied systems, suggesting the resilience of certain antibodies against variant-induced immune escape, as seen with the mAb 1D1-Fab. The newly identified mAb 002-S21F2 showed a similar efficacy profile to LY-COV1404, though with a slightly reduced binding to BF.7. In parallel, mAb REGN-10933 emerged as a potential therapeutic candidate against BF.7 and XBB.1.5, reflecting the importance of identifying variant-specific antibody interactions, akin to the binding optimization observed in BA.4/5 and XBB.1.5. And key residues that facilitate RBD-mAb binding were identified (T345, L441, K444, V445, and T500), alongside residues that hinder protein-protein interactions (D420, L455, K440, and S446). Particularly noteworthy was the inhibited binding of V445 and R509 with mAbs in the presence of mAb 002-S21F2, suggesting a mechanism for immune escape, especially through the reduction of V445 hydrophobicity. These findings enhance our comprehension of the binding interactions between mAbs and RBDs, contributing to the understanding of immune escape mechanisms. They also lay the groundwork for the design and optimization of antiviral drugs and have significant implications for the development of treatments against current and future coronaviruses.


Assuntos
Anticorpos Monoclonais , Anticorpos Neutralizantes , Antivirais , Simulação de Dinâmica Molecular , SARS-CoV-2
14.
Environ Res ; 260: 119604, 2024 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-39002636

RESUMO

Fluoride pollution and water scarcity are urgent issues. Reducing fluoride concentration in water is crucial. Kaolinite has been used to study adsorption and fluoride removal in water and to characterize material properties. The experimental results showed that the adsorption capacity of kaolinite decreased with increasing pH. The highest adsorption of fluoride occurred at pH 2, with a capacity of 11.1 mg/g. The fluoride removal efficiency remained high after four regeneration cycles. The fitting results with the Freundlich isotherm model and the external diffusion model showed that the non-homogeneous adsorption of kaolinite fit the adsorption behavior better. Finally, the adsorption mechanism was analyzed by FT-IR and XPS. The binding energies of various adsorption sites and the chemical adsorption properties of atomic states were discussed in relation to DFT calculations. The results showed that Al and H sites were the main binding sites, and the bonding stability for different forms of fluoride varies, with the size of Al-F (-7.498 eV) > H-F (-6.04 eV) > H-HF (-3.439 eV) > Al-HF (-3.283 eV). Furthermore, the density of states and Mulliken charge distribution revealed that the 2p orbital of F was found to be active in the adsorption process and was the main orbital for charge transfer.


Assuntos
Fluoretos , Caulim , Águas Residuárias , Poluentes Químicos da Água , Fluoretos/química , Fluoretos/análise , Caulim/química , Águas Residuárias/química , Adsorção , Poluentes Químicos da Água/química , Poluentes Químicos da Água/análise , Metalurgia , Teoria da Densidade Funcional , Eliminação de Resíduos Líquidos/métodos , Purificação da Água/métodos , Concentração de Íons de Hidrogênio
15.
Appl Opt ; 63(3): 865-873, 2024 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-38294403

RESUMO

In this paper, a high-quality germanene-polyvinyl alcohol (PVA) saturable absorber (SA) with a modulation depth of 3.05% and a saturation intensity of 17.95M W/c m 2 was prepared. Stable conventional mode-locking and harmonic mode-locking (HML) were achieved in germanene-based Er-doped fiber lasers (EDFL) using dispersion management techniques. In a cavity with a net dispersion value of -0.22p s 2, the conventional soliton had a center wavelength of 1558.2 nm, a repetition frequency of 19.09 MHz, and a maximum 3 dB spectrum bandwidth of 3.5 nm. The highest repetition frequencies achieved in cavities with net dispersion values of -2.81p s 2, -1.73p s 2, and -1.09p s 2 were 9.48 MHz, 12.75 MHz, and 12.10 MHz for HML, respectively. Furthermore, the effects of dispersion, power, and the polarization state on HML were systematically investigated. Our research results fully demonstrate the capability of germanene as an optical modulator in generating conventional mode-locked and harmonic mode-locked solitons. This provides meaningful references for promoting its application in ultrafast fiber lasers.

16.
Aging Clin Exp Res ; 36(1): 128, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38856860

RESUMO

BACKGROUND: Balance disorders can give rise to sensations of instability, lightheadedness, vertigo, disequilibrium, or syncope, ultimately leading to grave medical, physical, emotional, and societal ramifications. These conditions are highly prevalent among individuals aged 40 and above. Screen time encompasses activities associated with television viewing, video game playing, and non-work-related computer usage. Prolonged screen exposure may engender a spectrum of health issues and even elevate overall mortality rates. However, the available evidence on the potential link between excessive screen time and balance dysfunction remains limited. AIMS: The primary aim of this study was to explore the possible association between prolonged screen exposure and impaired balance function. METHODS: This cross-sectional study utilized data from participants who completed a comprehensive questionnaire in the NHANES database between 1999 and 2002, all of whom were aged over 40 and under 85 years. Participants' screen time was categorized into two groups (< 4 h/d and ≥4 h/d) for subsequent data analysis. Logistic regression, combined with propensity score matching (PSM), was employed to investigate the correlation between screen time and balance disorders. RESULTS: A total of 5176 participants were enrolled in this study, comprising 2,586 men and 2,590 women, with a prevalence rate of balance disorders at 25.7% (1331/5176). The incidence of balance disorders was found to be significantly higher among individuals who spent 4 hours or more per day on screen time compared to those with less screen time (P<0.001). Multivariate logistic analysis conducted on the unmatched cohort revealed a significant association between screen time and balance disorders, with an odds ratio (OR) 1.8 (95%CI 1.57 ∼ 2.05). These findings remained consistent even after adjusting for confounding factors, yielding an OR 1.43 (95%CI 1.24 ∼ 1.66). Moreover, the association persisted when employing various multivariate analyses such as propensity score matching adjusted model, standardized mortality ratio weighting model and pairwise algorithmic model; all resulting in ORs ranging from 1.38 to 1.43 and p-values < 0.001. CONCLUSIONS: After controlling for all covariates, screen time (watching TV, playing video games, and using computers outside of work) was associated with balance dysfunction among middle-aged and older adults. This finding may offer a possible idea for the prevention of dizziness and balance disorders. Nevertheless, additional research is imperative to further validate these results.


Assuntos
Inquéritos Nutricionais , Equilíbrio Postural , Tempo de Tela , Autorrelato , Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Estudos Transversais , Equilíbrio Postural/fisiologia , Adulto , Idoso de 80 Anos ou mais , Transtornos de Sensação/epidemiologia , Prevalência , Jogos de Vídeo , Estados Unidos/epidemiologia
17.
Ecotoxicol Environ Saf ; 284: 116905, 2024 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-39191133

RESUMO

Lanthanide-doped upconversion nanoparticles (Ln-UCNPs) have been considered promising materials for various fields, such as biomedical and industrial applications. However, data and reports regarding its toxicity and environmental risks are scarce. Under these circumstances, data must be obtained to fully understand potential toxicity and adverse outcome pathways. In the present study, the toxicity of uncoated Ln-UCNP cores (NaYF4:Yb, Er) was systematically assessed in zebrafish embryos during early developmental stages. Ln-UCNPs were found to have multiple toxic effects, such as effects on survival rates, delayed hatching times, shorter body lengths, altered heart rates and blood circulation (significantly reduced), and neurobehavioral impairments in response to photoperiod stimulation. Bioimaging showed that Ln-UCNPs were distributed on the chorion, eyes, and skin at 72 hpf. However, it accumulates in the pharynx, esophagus, and intestine after oral administration. Ln-UCNPs disrupt the diversity and abundance of host-associated microorganisms (gut microbiota) leading to an increase in the prevalence of harmful bacteria in zebrafish. Transcriptomic and Ingenuity Pathway Analysis (IPA) predicted Interleukin-8 (IL-8) signaling, neuroinflammation, cardiac hypertrophy signaling pathways, immune and inflammation-related response interferon-gamma (ifnγ), and miR-155 as key mediators in regulatory effects. Based on this, a causal network was built showing the strong links between the induced gene expression of differentially expressed genes (DEGs), such as nitric oxide synthase 2 (nos2) and tumor necrosis factor (tnf) upon Ln-UCNPs treatment, and with the downstream adverse outcomes, in particular, the promotion of apoptosis, liver damage, and inflammatory response. Finally, RT-qPCR analysis confirmed the up-regulated expression of nos2 and tnf in the exposed larvae, consistent with the observation of an increased number of fluorescence-labelled neutrophils and macrophages in lyz: DsRed transgenic zebrafish until 120 hpf exposure, which together demonstrated the proinflammatory effects of Ln-UCNPs on organisms. In conclusion, we illustrated the developmental toxicity, disruption of gut-microbiome, and proinflammatory effects of Ln-UCNP cores on zebrafish, and the causal network from IPA analysis may help further elucidate the adverse outcome pathway of Ln-UCNPs.

18.
Int J Mol Sci ; 25(17)2024 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-39273344

RESUMO

A major factor limiting the development of somatic cell nuclear transfer (SCNT) technology is the low success rate of pregnancy, mainly due to placental abnormalities disrupting the maternal-fetal balance during pregnancy. Although there has been some progress in research on the abnormal enlargement of cloned bovine placenta, there are still few reports on the direct regulatory mechanisms of enlarged cloned bovine placenta tissue. In this study, we conducted sequencing and analysis of transcriptomics, proteomics, and metabolomics of placental tissues from SCNT cattle (n = 3) and control (CON) cattle (n = 3). The omics analysis results indicate abnormalities in biological functions such as protein digestion and absorption, glycolysis/gluconeogenesis, the regulation of lipid breakdown, as well as glycerolipid metabolism, and arginine and proline metabolism in the placenta of SCNT cattle. Integrating these analyses highlights critical metabolic pathways affecting SCNT cattle placenta, including choline metabolism and unsaturated fatty acid biosynthesis. These findings suggest that aberrant expressions of genes, proteins, and metabolites in SCNT placentas affect key pathways in protein digestion, growth hormone function, and energy metabolism. Our results suggest that abnormal protein synthesis, growth hormone function, and energy metabolism in SCNT bovine placental tissues contribute to placental hypertrophy. These findings offer valuable insights for further investigation into the mechanisms underlying SCNT bovine placental abnormalities.


Assuntos
Metabolômica , Técnicas de Transferência Nuclear , Placenta , Proteômica , Transcriptoma , Animais , Bovinos , Feminino , Gravidez , Placenta/metabolismo , Proteômica/métodos , Metabolômica/métodos , Clonagem de Organismos , Perfilação da Expressão Gênica
19.
J Environ Manage ; 356: 120655, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38513589

RESUMO

High boron (B) stress degrades the soil environment and reduces plant productivity. Sugar beet has a high B demand and potential for remediation of B-toxic soils. However, the mechanism regarding the response of sugar beet plants and rhizosphere soil microbiome to high B stress is not clear. In the potted soil experiment, we set different soil effective B environments (0.5, 5, 10, 30, 50, and 100 mg kg-1) to study the growth status of sugar beets under different B concentrations, as well as the characteristics of soil enzyme activity and microbial community changes. The results showed that sugar beet growth was optimal at 5 mg kg-1 of B. Exceeding this concentration the tolerance index decreased. The injury threshold EC20 was reached at an available B concentration of 35.8 mg kg-1. Under the treatment of 100 mg kg-1, the B accumulation of sugar beet reached 0.22 mg plant-1, and the tolerance index was still higher than 60%, which had not yet reached the lethal concentration of sugar beet. The abundance of Acidobacteriota, Chloroflexi and Patescibacteria increased, which was beneficial to the resistance of sugar beet to high B stress. In summary, under high B stress sugar beet had strong tolerance, enhanced capacity for B uptake and enrichment, and changes in soil microbial community structure. This study provides a theoretical basis for clarifying the mechanism of sugar beet resistance to high B stress and soil remediation.


Assuntos
Beta vulgaris , Solo , Solo/química , Beta vulgaris/metabolismo , Beta vulgaris/microbiologia , Boro , Rizosfera , Verduras , Açúcares/metabolismo
20.
J Environ Manage ; 353: 120159, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38310797

RESUMO

Nicosulfuron is a common herbicide used to control weeds in maize fields. In northeast China, sugar beet is often grown as a subsequent crop after maize, and its frequently suffers from soil nicosulfuron residue damage, but the related toxicity evaluation and photosynthetic physiological mechanisms are not clear. Therefore, we experimented to evaluate the impacts of nicosulfuron residues on beet growth, photochemical properties, and antioxidant defense system. The results showed that when the nicosulfuron residue content reached 0.3 µg kg-1, it inhibited the growth of sugar beet. When it reached 36 µg kg-1 (GR50), the growth stagnated. Compared to the control group, a nicosulfuron residue of 36 µg kg-1 significantly decreased beet plant height (70.93 %), leaf area (91.85 %), dry weights of shoot (70.34 %) and root (32.70 %). It also notably reduced the potential photochemical activity (Fv/Fo) by 12.41 %, the light energy absorption performance index (PIabs) by 46.09 %, and light energy absorption (ABS/CSm) by 6.56 %. It decreased the capture (TRo/CSm) by 9.30 % and transferred energy (ETo/CSm) by 16.13 % per unit leaf cross-section while increasing the energy flux of heat dissipation (DIo/CSm) by 22.85 %. This ultimately impaired the photochemical capabilities of PSI and PSII, leading to a reduction in photosynthetic performance. Furthermore, nicosulfuron increased malondialdehyde (MDA) content while decreasing superoxide dismutase (SOD) and catalase (CAT) activities. In conclusion, this research clarified the toxicity risk level, lethal dose, and harm mechanism of the herbicide nicosulfuron residue. It provides a theoretical foundation for the rational use of herbicides in agricultural production and sugar beet planting management.


Assuntos
Beta vulgaris , Herbicidas , Piridinas , Compostos de Sulfonilureia , Beta vulgaris/metabolismo , Fotossíntese/fisiologia , Antioxidantes/metabolismo , Zea mays , Herbicidas/toxicidade , Açúcares
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