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1.
J Am Chem Soc ; 146(21): 14422-14426, 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38709624

RESUMO

Here we report a concise and divergent synthesis of scabrolide A and havellockate, representative members of polycyclic marine natural product furano(nor)cembranoids. The synthesis features a highly efficient exo-exo-endo radical cascade. Through the generation of two rings, three C-C bonds, and three contiguous stereocenters in one step, this remarkable transformation not only assembles the bowl-shaped, common 6-5-5 fused ring system from simple building blocks but also precisely installs the functionalities at desired positions and sets the stage for further divergent preparation of both target molecules. Further studies reveal that the robust and unusual 6-endo radical addition in the cascade is likely facilitated by the rigidity of the substrate.

2.
BMC Plant Biol ; 24(1): 390, 2024 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-38730367

RESUMO

Granulation of juice sacs is a physiological disorder, which affects pomelo fruit quality. Here, the transcriptome and ubiquitinome of the granulated juice sacs were analyzed in Guanxi pomelo. We found that lignin accumulation in the granulated juice sacs was regulated at transcription and protein modification levels. In transcriptome data, we found that the genes in lignin biosynthesis pathway and antioxidant enzyme system of the granulated juice sacs were significantly upregulated. However, in ubiquitinome data, we found that ubiquitinated antioxidant enzymes increased in abundance but the enzyme activities decreased after the modification, which gave rise to reactive oxygen species (ROS) contents in granulated juice sacs. This finding suggests that ubiquitination level of the antioxidant enzymes is negatively correlated with the enzyme activities. Increased H2O2 is considered to be a signaling molecule to activate the key gene expressions in lignin biosynthesis pathway, which leads to the lignification in granulated juice sacs of pomelo. This regulatory mechanism in juice sac granulation of pomelo was further confirmed through the verification experiment using tissue culture by adding H2O2 or dimethylthiourea (DMTU). Our findings suggest that scavenging H2O2 and other ROS are important for reducing lignin accumulation, alleviating juice sac granulation and improving pomelo fruit quality.


Assuntos
Citrus , Lignina , Lignina/metabolismo , Citrus/metabolismo , Citrus/genética , Sucos de Frutas e Vegetais/análise , Espécies Reativas de Oxigênio/metabolismo , Transcriptoma , Peróxido de Hidrogênio/metabolismo , Regulação da Expressão Gênica de Plantas , Frutas/metabolismo , Frutas/genética , Antioxidantes/metabolismo
3.
Anal Chem ; 95(39): 14665-14674, 2023 10 03.
Artigo em Inglês | MEDLINE | ID: mdl-37679861

RESUMO

A sandwich immunoassay theoretically exhibits higher sensitivity and specificity compared to a competitive counterpart; however, it is extremely difficult to obtain a pair of antibodies that can bind to a small molecule simultaneously, which is always thought to be a single epitope. In the present study, abamectin (ABM) was selected to prove the effect of hapten design and antibody recognition properties on the development of a sandwich immunoassay for small molecules. First, the epitopes of ABM were roughly located, and epitope distances were determined. Then, two haptens were designed by introducing spacer arms at the C4″-OH and C5-OH of ABM, respectively, aiming to provide the longest epitope distances. A total of seven rabbit polyclonal antibodies (pAbs) and 21 mouse monoclonal antibodies (mAbs) with various recognition properties were obtained. Extensive combinatorial associations of antibody pairs for simultaneously binding to ABM were performed, and only two mAb-mAb pairs were observed to achieve a sandwich immunoassay for ABM with a total success rate of 0.27%. The best mAb pair for sandwich immunoassay was confirmed by surface plasmon resonance, used to develop a sandwich immunoassay, and then evaluated by cross-reactivities and molecular docking with structurally similar analogues and abamectin. Altogether, the study provided a theoretical foundation as well as practical experience and demonstrated the importance of careful hapten design and extensive antibody screening to successfully establish the sandwich immunoassay for small molecules.


Assuntos
Anticorpos Monoclonais , Haptenos , Animais , Camundongos , Coelhos , Simulação de Acoplamento Molecular , Anticorpos Monoclonais/química , Imunoensaio , Epitopos , Ensaio de Imunoadsorção Enzimática
4.
Anal Chem ; 94(51): 17843-17852, 2022 12 27.
Artigo em Inglês | MEDLINE | ID: mdl-36519948

RESUMO

The pursuit of the limit between dimensionalities is a scientific goal with high applicability. Sandwich immunoassay, usually based on two antibodies binding two epitopes, is one of the most popular mainstay tools in both academic and industrial fields. Herein, we determined and evaluated the minimum distance of two epitopes in sandwich immunoassays for small molecules. Briefly, nine model analytes comprising two hapten epitopes, that is, melamine (MEL) and p-nitroaniline (NIA), were designed by increasing the linear chain linkers brick by brick. Two groups of monoclonal antibodies (mAbs) were produced with different recognition properties toward MEL and NIA using 12 new haptens with different spacer arms. The results indicated that two epitopes of the analyte with a distance of only 2.4 Å could be simultaneously bound by two mAbs, which is the known limit of epitope distance in sandwich immunoassays thus far. We further found that an epitope distance of below 8.8 Å for the analyte generally induces noticeable steric hindrance of antibodies, preventing a sandwich immunoassay with high probability. These observations were investigated and evaluated by molecular docking, molecular dynamics, and surface plasmon resonance and using model and real analytes. Altogether, we determined the minimum distance of two epitopes and explored the molecular mechanism of the antibody-analyte-antibody ternary complex in sandwich immunoassays, providing a theoretical basis for hapten design, antibody discovery and development, and sandwich immunoassay establishment for small molecules.


Assuntos
Anticorpos Monoclonais , Haptenos , Epitopos , Simulação de Acoplamento Molecular , Imunoensaio/métodos , Anticorpos Monoclonais/química
5.
Sensors (Basel) ; 22(9)2022 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-35591170

RESUMO

In recent decades, zebrafish have become an increasingly popular laboratory organism in several fields of research due to their ease of reproduction and rapid maturation. In particular, shoaling behavior has attracted the attention of many researchers. This article presents a fully printed robotic model used to sense and stimulate shoaling behavior in zebrafish (Danio rerio). Specifically, we exposed laboratory-fabricated replicated materials to critical acid/base/salt environments and evaluated the mechanical, optical, and surface properties after a three-month immersion period. Focusing on weatherability, these test samples maintained high tensile strength (~45 MPa) and relatively similar transmission (>85%T in the visible region), as determined by UV−vis/FTIR spectroscopy. Three-dimensional (3D) printing technology allowed printing of models with different sizes and appearances. We describe the sense of zebrafish responses to replicas of different sizes and reveal that replicas approximating the true zebrafish size (3 cm) are more attractive than larger replicas (5 cm). This observation suggests that larger replicas appear as predators to the zebrafish and cause fleeing behavior. In this study, we determined the weatherability of a high-transparency resin and used it to fabricate a fully printed driving device to induce shoaling by zebrafish. Finally, we demonstrate a weathering-resistant (for three months) 3D-printed decoy model with potential utility for future studies of outdoor shoaling behavior, and the result has the potential to replace the traditional metal frame devices used in outdoor experiments.


Assuntos
Procedimentos Cirúrgicos Robóticos , Peixe-Zebra , Animais , Comportamento Animal/fisiologia , Impressão Tridimensional , Comportamento Social
6.
Nano Lett ; 20(4): 2857-2864, 2020 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-32163291

RESUMO

Two-dimensional spiral plasmonic structures have emerged as a versatile approach to generate near-field vortex fields with tunable topological charges. We demonstrate here a far-field approach to observe the chiral second-harmonic generation (SHG) at designated visible wavelengths from a single plasmonic vortex metalens. This metalens comprises an Archimedean spiral slit fabricated on atomically flat aluminum epitaxial film, which allows for precise tuning of plasmonic resonances and subsequent transfer of two-dimensional materials on top of the spiral slit. The nonlinear optical measurements show a giant SHG circular dichroism. Furthermore, we have achieved an enhanced chiral SHG conversion efficiency (about an order of magnitude greater than the bare aluminum lens) from monolayer tungsten disulfide (WS2)/aluminum metalens, which is designed at the C-exciton resonance of WS2. Since the C-exciton is not a valley exciton, the enhanced chiral SHG in this hybrid system originates from the plasmonic vortex field-enhanced SHG under the optical spin-orbit interaction.

7.
Int J Mol Sci ; 22(20)2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-34681776

RESUMO

Anthocyanins are natural pigments with antioxidant effects that exist in various fruits and vegetables. The accumulation of anthocyanins is induced by environmental signals and regulated by transcription factors in plants. Numerous evidence has indicated that among the environmental factors, light is one of the most signal regulatory factors involved in the anthocyanin biosynthesis pathway. However, the signal transduction of light and molecular regulation of anthocyanin synthesis remains to be explored. Here, we focus on the research progress of signal transduction factors for positive and negative regulation in light-dependent and light-independent anthocyanin biosynthesis. In particular, we will discuss light-induced regulatory pathways and related specific regulators of anthocyanin biosynthesis in plants. In addition, an integrated regulatory network of anthocyanin biosynthesis controlled by transcription factors is discussed based on the significant progress.


Assuntos
Antocianinas/biossíntese , Luz , Redes e Vias Metabólicas/efeitos da radiação , Regulação da Expressão Gênica de Plantas/efeitos da radiação , Redes e Vias Metabólicas/genética , Desenvolvimento Vegetal/genética , Desenvolvimento Vegetal/efeitos da radiação , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Proteínas de Plantas/efeitos da radiação , Plantas/genética , Plantas/metabolismo , Plantas/efeitos da radiação
8.
Molecules ; 26(18)2021 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-34577037

RESUMO

Theoretically, sandwich immunoassay is more sensitive and has a wider working range than that of competitive format. However, it has been thought that small molecules cannot be detected by the sandwich format due to their limited size. In the present study, we proposed a novel strategy for achieving sandwich immunoassay of ß-lactams with low molecular weights. Firstly, five ß-lactam antibiotics were selected to bind with penicillin binding protein (PBP)2x* to form complexes. Then, monoclonal and polyclonal antibodies against PBP2x*-ß-lactams complexes were produced by animal immunization. Subsequently, the optimal pairing antibodies were utilized to establish sandwich immunoassay for detection of 18 PBP2x*-ß-lactam complexes. Among them, ceftriaxone could be detected at as low as 1.65 ng/mL with working range of 1-1000 ng/mL in milk. To reveal the detection mechanism, computational chemistry and molecular recognition study were carried out. The results showed that ß-lactams with a large size and complex structures maybe conducive to induce conformational changes of PBP2x*, and then exhibit greater possibility of being detected by sandwich immunoassay after combination with PBP2x*. This study provides insights for subsequent investigations of anti-metatype antibody screening and sandwich immunoassay establishment for small-molecule detection.


Assuntos
Proteínas de Ligação às Penicilinas , Streptococcus pneumoniae , beta-Lactamas , Antibacterianos , Testes de Sensibilidade Microbiana
9.
Biochem Biophys Res Commun ; 527(4): 1057-1063, 2020 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-32439176

RESUMO

Salidroside possesses excellent anti-tumor activity in many types of malignant tumor. In present study, we focused on the effects of salidroside on hepatocellular carcinoma (HCC). The viability of human HCC cells was assayed using MTT. Apoptosis in the cells and tissues samples were detected by Annexin V/PI or TUNEL staining assays. The levels of apoptosis and endoplasmic reticulum (ER) stress related proteins were measured by western blotting analysis. We found salidroside significantly suppressed cell viability and promoted apoptosis in HCC cells. Salidroside could activate intrinsic and extrinsic apoptotic pathways, by increasing activities of caspase-3, caspase-8 and caspase-9, up-regulating levels of Bax, Cytochrome c and decreasing level of Bcl-2 in HepG2 cells. Moreover, it was found salidroside induced ER stress and increased expression of p-PERK, eIF2a, p-eIF2a, ATF-6 and CHOP in HepG2 cells. Interestingly, knockdown of CHOP impaired salidroside induced inhibitory effects on HepG2 cells, suggesting the important role of ER stress in cytotoxic effect of salidroside. Finally, we have confirmed salidroside induced ER stress and inhibited development of HepG2 in an xenograft mouse model. In conclusion, our data suggest salidroside inhibits viability and induces apoptosis of HCC both in vitro and vivo, and this effect is partially mediated by activation of ER stress.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Apoptose/efeitos dos fármacos , Carcinoma Hepatocelular/tratamento farmacológico , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Glucosídeos/farmacologia , Neoplasias Hepáticas/tratamento farmacológico , Fenóis/farmacologia , Animais , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/uso terapêutico , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Glucosídeos/química , Glucosídeos/uso terapêutico , Células Hep G2 , Humanos , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Masculino , Camundongos Endogâmicos BALB C , Camundongos Nus , Fenóis/química , Fenóis/uso terapêutico , Rhodiola/química
10.
Mol Cell ; 45(6): 777-89, 2012 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-22364742

RESUMO

Abnormal inflammatory signaling activation occurs commonly in cancer cells. However, how it is initiated and maintained and its roles in early stages of tumorigensis are largely unknown. Here, we report that the monocyte-derived MCP-1-induced transformation of immortal breast epithelial cells is triggered by transient activation of MEK/ERK and IKK/NF-κB pathways and maintained by constitutive activation of a feed-forward inflammatory signaling circuit composed of miR-200c, p65, JNK2, HSF1, and IL6. Suppression of miR-200c by IL6 constitutively activates p65/RelA and JNK2, and the latter phosphorylates and activates HSF1. In turn, HSF1 triggers demethylation of the IL6 promoter that facilitates the binding of p65 and c-Jun, which together drive constitutive IL6 transcription. Importantly, this signaling circuit is manifest in human cancer cells and in a mouse model of ErbB2-driven breast cancer, where IL6 loss significantly impairs tumorigenesis. Therefore, targeting this signaling circuit represents an effective therapeutic avenue for breast cancer prevention and treatment.


Assuntos
Transformação Celular Neoplásica/genética , Inflamação/metabolismo , Interleucina-6/metabolismo , MicroRNAs/metabolismo , Animais , Mama/citologia , Quimiocina CCL2/genética , Quimiocina CCL2/metabolismo , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Receptor alfa de Estrogênio/metabolismo , Feminino , Fatores de Transcrição de Choque Térmico , Humanos , Inflamação/genética , Interleucina-6/genética , Proteínas Quinases JNK Ativadas por Mitógeno/genética , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Camundongos , Camundongos Transgênicos , Proteína Quinase 9 Ativada por Mitógeno/genética , Proteína Quinase 9 Ativada por Mitógeno/metabolismo , Quinases de Proteína Quinase Ativadas por Mitógeno/genética , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , NF-kappa B/genética , NF-kappa B/metabolismo , Regiões Promotoras Genéticas , Fator de Transcrição STAT3/genética , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais/genética , Fator de Transcrição RelA/genética , Fator de Transcrição RelA/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
11.
J Comput Assist Tomogr ; 44(2): 255-261, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32195805

RESUMO

OBJECTIVE: We aimed to determine the effects of recombinant human growth hormone (rhGH) replacement on cognitive function in subjects with poststroke cognitive impairment using resting-state functional magnetic resonance imaging. METHODS: We included 60 patients with a first-ever stroke for 3 months and a diagnosis of cognitive impairment who were randomized 1:1 to receive either rhGH subcutaneously or placebo injection for 6 months. All subjects were required to receive the same rehabilitative therapy program. Both groups were subjected to pretreatment and posttreatment neuropsychological assessment using the Montreal Cognitive Assessment, serum neurotrophic factors, biomarkers of glucose and lipid metabolism, and functional magnetic resonance imaging during 6 months of the study period. The pattern of brain activity was determined by examining the functional connectivity and amplitude of low-frequency fluctuations (ALFF) of blood oxygen level dependent signal. RESULTS: Forty-three (82.7%) completed the study. Treatment with rhGH reduced levels of triglycerides and low-density lipoprotein cholesterol but did not significantly altered plasma concentrations of glucose and glycated hemoglobin. We found a significant increase in serum insulin-like growth factor 1 levels (32.6%; P < 0.001) in the rhGH-treated group compared with that in the controls. After 6 months of rhGH treatment, mean Montreal Cognitive Assessment score improved from 16.31 (5.32) to 21.19 (6.54) (P < 0.001). The rhGH group showed significant increased area of activation with increased ALFF values in the regions of the frontal lobe, putamen, temporal lobe, and thalamus (P < 0.05), relative to the baseline conditions. The correlation analysis revealed that the ALFF and functional connectivity of default mode network was positively correlated with the ΔMoCA score and ΔIGF-1 levels; that is, the more the scale score increased, the higher the functional connection strength. No undesirable adverse effects were observed. CONCLUSIONS: The rhGH replacement has a significant impact on global and domain cognitive functions in poststroke cognitive impairment.


Assuntos
Disfunção Cognitiva/complicações , Disfunção Cognitiva/tratamento farmacológico , Hormônio do Crescimento Humano/uso terapêutico , Imageamento por Ressonância Magnética/métodos , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/tratamento farmacológico , Encéfalo/diagnóstico por imagem , Encéfalo/efeitos dos fármacos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Resultado do Tratamento
12.
Mediators Inflamm ; 2020: 3019378, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32104147

RESUMO

CD19+CD24hiCD38hi B cells are immature transitional B cells that, in normal individuals, exert suppressive effects by IL-10 production but are quantitatively altered and/or functionally impaired in individuals with various autoimmune diseases. Primary biliary cholangitis (PBC), an autoimmune disease, clinically presents as chronic cholestasis and nonsuppurative destructive cholangitis. A role for CD19+CD24hiCD38hi B cells in PBC is unknown. This study investigated the frequency and functional variation of circulating CD19+CD24hiCD38hi B cells in PBC patients. Flow cytometry was employed to quantify the percentage of CD19+CD24hiCD38hi B cells in peripheral blood samples. Correlations between CD19+CD24hiCD38hi B cells and routine laboratory parameters were assessed. Levels of IL-10, TNF-α, IL-6 and IL-12, and Tim-1 in CD19+CD24hiCD38hi B cells from PBC patients were analyzed. The effect of CD19+CD24hiCD38hi B cells on CD4+T cell differentiation was evaluated. The percentage of CD19+CD24hiCD38hi B cells in PBC patients was significantly higher than in healthy controls and was positively correlated with liver cholestasis. After activation by anti-B cell receptor and CpG, the production of IL-10 was decreased and the production of IL-6 and IL-12 was increased in CD19+CD24hiCD38hi B cells from PBC patients. Moreover, Tim-1 levels were significantly downregulated in CD19+CD24hiCD38hi B cells from PBC patients. Coculture showed that PBC-derived CD19+CD24hiCD38hi B cells were less capable of CD4+T cell inhibition, but promoted Th1 cell differentiation. In conclusion, PBC patients have expanded percentages, but impaired CD19+CD24hiCD38hi B cells, which correlate with disease damage. In PBC patients, this B cell subset has a skewed proinflammatory cytokine profile and a decreased capacity to suppress immune function, which may contribute to the pathogenesis of PBC.


Assuntos
ADP-Ribosil Ciclase 1/metabolismo , Antígenos CD19/metabolismo , Linfócitos B/metabolismo , Linfócitos B/patologia , Antígeno CD24/metabolismo , Cirrose Hepática Biliar/imunologia , Cirrose Hepática Biliar/patologia , Idoso , Diferenciação Celular/fisiologia , Feminino , Citometria de Fluxo , Receptor Celular 1 do Vírus da Hepatite A/metabolismo , Humanos , Interleucina-10/metabolismo , Interleucina-12/metabolismo , Interleucina-6/metabolismo , Cirrose Hepática Biliar/metabolismo , Masculino , Pessoa de Meia-Idade , Células-Tronco de Sangue Periférico/imunologia , Células-Tronco de Sangue Periférico/metabolismo , Células-Tronco de Sangue Periférico/patologia , Fator de Necrose Tumoral alfa/metabolismo
13.
J Virol ; 90(4): 1694-704, 2016 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-26581994

RESUMO

UNLABELLED: Vaccine manufacturing costs prevent a significant portion of the world's population from accessing protection from vaccine-preventable diseases. To enhance vaccine production at reduced costs, a genome-wide RNA interference (RNAi) screen was performed to identify gene knockdown events that enhanced poliovirus replication. Primary screen hits were validated in a Vero vaccine manufacturing cell line using attenuated and wild-type poliovirus strains. Multiple single and dual gene silencing events increased poliovirus titers >20-fold and >50-fold, respectively. Host gene knockdown events did not affect virus antigenicity, and clustered regularly interspaced short palindromic repeat (CRISPR)-Cas9-mediated knockout of the top candidates dramatically improved viral vaccine strain production. Interestingly, silencing of several genes that enhanced poliovirus replication also enhanced replication of enterovirus 71, a clinically relevant virus to which vaccines are being targeted. The discovery that host gene modulation can markedly increase virus vaccine production dramatically alters mammalian cell-based vaccine manufacturing possibilities and should facilitate polio eradication using the inactivated poliovirus vaccine. IMPORTANCE: Using a genome-wide RNAi screen, a collection of host virus resistance genes was identified that, upon silencing, increased poliovirus and enterovirus 71 production by from 10-fold to >50-fold in a Vero vaccine manufacturing cell line. This report provides novel insights into enterovirus-host interactions and describes an approach to developing the next generation of vaccine manufacturing through engineered vaccine cell lines. The results show that specific gene silencing and knockout events can enhance viral titers of both attenuated (Sabin strain) and wild-type polioviruses, a finding that should greatly facilitate global implementation of inactivated polio vaccine as well as further reduce costs for live-attenuated oral polio vaccines. This work describes a platform-enabling technology applicable to most vaccine-preventable diseases.


Assuntos
Poliomielite/prevenção & controle , Vacinas contra Poliovirus/isolamento & purificação , Poliovirus/isolamento & purificação , Poliovirus/fisiologia , Tecnologia Farmacêutica/métodos , Replicação Viral , Animais , Vacinas Atenuadas/isolamento & purificação , Células Vero , Cultura de Vírus/métodos
14.
J Gen Virol ; 97(3): 659-668, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26683768

RESUMO

Vaccination with live-attenuated polio vaccine has been the primary reason for the drastic reduction of poliomyelitis worldwide. However, reversion of this attenuated poliovirus vaccine occasionally results in the emergence of vaccine-derived polioviruses that may cause poliomyelitis. Thus, the development of anti-poliovirus agents remains a priority for control and eradication of the disease. MicroRNAs (miRNAs) have been shown to regulate viral infection through targeting the viral genome or reducing host factors required for virus replication. However, the roles of miRNAs in poliovirus (PV) replication have not been fully elucidated. In this study, a library of 1200 miRNA mimics was used to identify miRNAs that govern PV replication. High-throughput screening revealed 29 miRNAs with antiviral properties against Sabin-2, which is one of the oral polio vaccine strains. In particular, miR-555 was found to have the most potent antiviral activity against three different oral polio attenuated vaccine strains tested. The results show that miR-555 reduced the level of heterogeneous nuclear ribonucleoprotein C1/C2 (hnRNP C) required for PV replication in the infected cells, which in turn resulted in reduction of PV positive-strand RNA synthesis and production of infectious progeny. These findings provide the first evidence for the role of miR-555 in PV replication and reveal that miR-555 could contribute to the development of antiviral therapeutic strategies against PV.


Assuntos
MicroRNAs/imunologia , Poliomielite/imunologia , Poliovirus/fisiologia , Replicação Viral , Regulação Viral da Expressão Gênica , Ribonucleoproteínas Nucleares Heterogêneas/genética , Ribonucleoproteínas Nucleares Heterogêneas/imunologia , Interações Hospedeiro-Patógeno , Humanos , MicroRNAs/genética , Poliomielite/genética , Poliomielite/virologia , Poliovirus/genética , RNA Viral/genética , RNA Viral/metabolismo
15.
PLoS One ; 19(6): e0304691, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38833435

RESUMO

With the rapid development of intelligent connected vehicles, there is an increasing demand for hardware facilities and onboard systems of driver assistance systems. Currently, most vehicles are constrained by the hardware resources of onboard systems, which mainly process single-task and single-sensor data. This poses a significant challenge in achieving complex panoramic driving perception technology. While the panoramic driving perception algorithm YOLOP has achieved outstanding performance in multi-task processing, it suffers from poor adaptability of feature map pooling operations and loss of details during downsampling. To address these issues, this paper proposes a panoramic driving perception fusion algorithm based on multi-task learning. The model training involves the introduction of different loss functions and a series of processing steps for lidar point cloud data. Subsequently, the perception information from lidar and vision sensors is fused to achieve synchronized processing of multi-task and multi-sensor data, thereby effectively improving the performance and reliability of the panoramic driving perception system. To evaluate the performance of the proposed algorithm in multi-task processing, the BDD100K dataset is used. The results demonstrate that, compared to the YOLOP model, the multi-task learning network performs better in lane detection, drivable area detection, and vehicle detection tasks. Specifically, the lane detection accuracy improves by 11.6%, the mean Intersection over Union (mIoU) for drivable area detection increases by 2.1%, and the mean Average Precision at 50% IoU (mAP50) for vehicle detection improves by 3.7%.


Assuntos
Algoritmos , Condução de Veículo , Humanos , Condução de Veículo/psicologia , Análise e Desempenho de Tarefas
16.
J Glob Antimicrob Resist ; 38: 1-5, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38777179

RESUMO

BACKGROUND: Enterococcus faecium (E. faecium) stands as a prominent pathogen contributing to Gram-positive bacterial infections in individuals who have undergone liver transplantation. CASE PRESENTATION: A 66-year-old male with a three-year history of treated anxiety disorder was admitted to our hospital due to recurrent abdominal distension and oliguria. He was diagnosed with hepatic veno-occlusive disease (HVOD), hepatic failure, pneumonia, renal insufficiency and abdominal ascites. A liver transplantation procedure was performed, but the patient's infection index increased on the first day after surgery. Empirical antibiotic therapy with ceftriaxone and meropenem and preventive antifungal therapy were applied. Sputum culture, blood culture, ascites culture and bronchoalveolar lavage fluid (BALF) next-generation sequencing (NGS), revealed the presence of E. faecium. Given the application of various nephrotoxic immunosuppressive agents after liver transplantation, pre-existing renal insufficiency, severe bone marrow suppression, and a history of anxiety disorder treated with sertraline, contezolid was added for the treatment of the Gram-positive bacterial infection. Sixteen days after surgery, cultures from ascites and sputum yielded negative results for fungi and bacteria. Contezolid was subsequently discontinued without any reported adverse events during follow-up. CONCLUSION: Treatment with contezolid as the first-line therapy for sepsis and pneumonia caused by E. faecium following liver transplantation has shown satisfactory efficacy and safety. Therefore, contezolid may hold great promise for managing this life-threatening condition.

17.
PLoS One ; 19(2): e0296782, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38306357

RESUMO

Based Correctly handling the creativity of employees who have not been adopted is not only conducive to continuously stimulating employees' creativity and improving individual innovation performance, but also conducive to making the best use of organizational resources. This study integrates conservation of resource theory (COR) and social information processing theory to explore the influence of bootleg innovation behavior in organizations on individual innovation performance, as well as the mediating role of cognitive flexibility and the moderating role of leadership emotional intelligence. A three-stage time-lagged research design is used to obtain a valid sample of 327 employees from China. The PROCESS macro for SPSS was applied to test the hypothesized relationships. Findings demonstrated that bootleg innovation is positively related to individual innovation performance; cognitive flexibility mediates the relationship between bootleg innovation and individual innovation performance. Moreover, leadership emotional intelligence moderates the relationship between bootleg innovation and individual innovation performance and between bootleg innovation and cognitive flexibility and between cognitive flexibility and individual innovation performance respectively. The conclusion of the study not only provides a theoretical basis for individuals and leaders to deal with employees' creative abortion, but also provides a new thinking mode for how to maximize the effectiveness of unaccepted ideas and promote individual innovation performance.


Assuntos
Aborto Induzido , Liderança , Feminino , Gravidez , Humanos , Cognição , China , Inteligência Emocional
18.
PLoS One ; 19(2): e0293454, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38349897

RESUMO

In a dynamic and competitive business environment, managerial ability emerges as a pivotal strategic factor for capitalizing on new opportunities within the technological revolution and digital transformation of enterprises. Based on data from Chinese A-share listed firms spanning from 2009 to 2019, this study integrates insights from the upper echelons theory and the behavioral theory of the firm to investigate the moderating roles of historical aspiration shortfalls and industrial competitiveness on the relationship between managerial ability and enterprise digital transformation from internal and external pressure perspectives. Our findings indicate a positive impact of managerial ability on digital transformation. The relationship between managerial ability and digital transformation is reinforced by historical aspiration shortfalls; nevertheless, industrial competitiveness has attenuated the aforementioned relationship. This study contributes to a better understanding of the strategic implications of managerial ability within the context of organizational innovation strategies. It offers valuable insights into the decision-making processes of firms as they navigate the challenges of digital transformation within an ever-evolving business environment.

19.
Front Psychol ; 15: 1371936, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38840737

RESUMO

Introduction: Career construction theory proposes that adaptivity affects career adapting through career adaptability. However, research on the mechanism of this pathway remains scarce. By applying career construction theory and conservation of resources theory, we hypothesize that career adaptability (concern, control, curiosity, and confidence) mediates the relationship between empathetic leadership (adaptivity) and innovative behavior (career adapting). Moreover, we posit that uncertain avoidance moderates the mediating mechanism. Methods: Our study used SPSS23 and bootstrap methods (PROCESS) to test the proposed model. The sample comprised 301 employees from different firms in various industries. In this study, empathetic leadership-5, career adaptability-24, uncertainty avoidance-5, and innovative behavior-6 scales were used to measure empathetic leadership, career adaptability, and uncertainty avoidance. Results: The results revealed that (1) empathetic leadership is positively related to employees' innovative behavior (2) Concern (H2a), control (H2b), curiosity (H2c), and confidence (H2d) mediate the relations between empathetic leadership and employee's innovative behavior (3) Uncertainty avoidance moderates the relationship between empathetic leadership and concern (H3a), control (H3b), curiosity (H3c), and confidence (H3d), such that this relationship is stronger when uncertainty avoidance is higher (4) Uncertainty avoidance moderates the indirect relationship between empathetic leadership and employee innovative behavior through concern (H4a), control (H4b), curiosity (H4c), and confidence (H4d), such that this indirect relationship will be stronger when uncertainty avoidance is high than when it is low. Conclusion: We investigated how empathetic leadership affects innovative behavior. Based on career construction theory and conservation of resources theory, we also tested the hypothesis that concern, control, curiosity, and confidence play mediating roles in linking empathetic leadership (career adaptivity) to innovative behavior (career adapting). In addition, this study found that uncertainty avoidance does not always have negative effects. People with a high uncertainty avoidance tendency may be dependent more on empathetic leadership to improve their career adaptability, which promotes their innovative behavior.

20.
J Hazard Mater ; 469: 133977, 2024 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-38492395

RESUMO

The immunogenicity of haptens determines the performance of the resultant antibody for small molecules. Rigidity is one of the basic physicochemical properties of haptens. However, few studies have investigated the effect of hapten rigidity on the strength of an immune response and overall antibody performance. Herein, we introduce three molecular descriptors that quantify hapten rigidity. By using of these descriptors, four rifamycin haptens with varied rigidity were designed. The structural and physicochemical feasibility of the designed haptens was then assessed by computational chemistry. Immunization demonstrated that the strength of induced immune responses, i.e., the titer and affinity of antiserum, was significantly increased with increased rigidity of haptens. Furthermore, molecular dynamic simulations demonstrated conformation constraint of rigid haptens contributed to the initial binding and activation of naïve B cells. Finally, a highly sensitive indirect competitive enzyme-linked immunosorbent assay was developed for detection of rifaximin, with an IC50 of 1.1 µg/L in buffer and a limit of detection of 0.2-11.3 µg/L in raw milk, river water, and soil samples. This work provides new insights into the effect of hapten rigidity on immunogenicity and offers new hapten design strategies for antibody discovery and vaccine development of small molecules.


Assuntos
Anticorpos , Rifamicinas , Ensaio de Imunoadsorção Enzimática , Imunoensaio , Haptenos
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