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1.
Cell ; 149(4): 923-35, 2012 May 11.
Artículo en Inglés | MEDLINE | ID: mdl-22559944

RESUMEN

Structural genomic variations represent a major driving force of evolution, and a burst of large segmental gene duplications occurred in the human lineage during its separation from nonhuman primates. SRGAP2, a gene recently implicated in neocortical development, has undergone two human-specific duplications. Here, we find that both duplications (SRGAP2B and SRGAP2C) are partial and encode a truncated F-BAR domain. SRGAP2C is expressed in the developing and adult human brain and dimerizes with ancestral SRGAP2 to inhibit its function. In the mouse neocortex, SRGAP2 promotes spine maturation and limits spine density. Expression of SRGAP2C phenocopies SRGAP2 deficiency. It underlies sustained radial migration and leads to the emergence of human-specific features, including neoteny during spine maturation and increased density of longer spines. These results suggest that inhibition of SRGAP2 function by its human-specific paralogs has contributed to the evolution of the human neocortex and plays an important role during human brain development.


Asunto(s)
Encéfalo/citología , Encéfalo/embriología , Proteínas Activadoras de GTPasa/genética , Duplicación de Gen , Neuronas/citología , Duplicaciones Segmentarias en el Genoma , Animales , Movimiento Celular , Espinas Dendríticas/metabolismo , Evolución Molecular , Humanos , Ratones , Datos de Secuencia Molecular , Neuronas/metabolismo , Estructura Terciaria de Proteína , Especificidad de la Especie
2.
Nature ; 598(7881): 495-499, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34497423

RESUMEN

Plants deploy cell-surface and intracellular leucine rich-repeat domain (LRR) immune receptors to detect pathogens1. LRR receptor kinases and LRR receptor proteins at the plasma membrane recognize microorganism-derived molecules to elicit pattern-triggered immunity (PTI), whereas nucleotide-binding LRR proteins detect microbial effectors inside cells to confer effector-triggered immunity (ETI). Although PTI and ETI are initiated in different host cell compartments, they rely on the transcriptional activation of similar sets of genes2, suggesting pathway convergence upstream of nuclear events. Here we report that PTI triggered by the Arabidopsis LRR receptor protein RLP23 requires signalling-competent dimers of the lipase-like proteins EDS1 and PAD4, and of ADR1 family helper nucleotide-binding LRRs, which are all components of ETI. The cell-surface LRR receptor kinase SOBIR1 links RLP23 with EDS1, PAD4 and ADR1 proteins, suggesting the formation of supramolecular complexes containing PTI receptors and transducers at the inner side of the plasma membrane. We detected similar evolutionary patterns in LRR receptor protein and nucleotide-binding LRR genes across Arabidopsis accessions; overall higher levels of variation in LRR receptor proteins than in LRR receptor kinases are consistent with distinct roles of these two receptor families in plant immunity. We propose that the EDS1-PAD4-ADR1 node is a convergence point for defence signalling cascades, activated by both surface-resident and intracellular LRR receptors, in conferring pathogen immunity.


Asunto(s)
Proteínas de Arabidopsis/metabolismo , Arabidopsis/inmunología , Hidrolasas de Éster Carboxílico/metabolismo , Proteínas de Unión al ADN/metabolismo , Inmunidad de la Planta , Proteínas Serina-Treonina Quinasas/metabolismo , Proteínas de Arabidopsis/química , Hidrolasas de Éster Carboxílico/química , Proteínas de Unión al ADN/química , Dominios Proteicos , Proteínas Quinasas/química , Proteínas Quinasas/metabolismo , Multimerización de Proteína , Proteínas Serina-Treonina Quinasas/química , Receptores de Superficie Celular/química , Receptores de Superficie Celular/metabolismo
3.
PLoS Pathog ; 20(6): e1012319, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38885290

RESUMEN

Candida albicans is a leading cause of intravascular catheter-related infections. The capacity for biofilm formation has been proposed to contribute to the persistence of this fungal pathogen on catheter surfaces. While efforts have been devoted to identifying microbial factors that modulate C. albicans biofilm formation in vitro, our understanding of the host factors that may shape C. albicans persistence in intravascular catheters is lacking. Here, we used multiphoton microscopy to characterize biofilms in intravascular catheters removed from candidiasis patients. We demonstrated that, NETosis, a type of neutrophil cell death with antimicrobial activity, was implicated in the interaction of immune cells with C. albicans in the catheters. The catheter isolates exhibited reduced filamentation and candidalysin gene expression, specifically in the total parenteral nutrition culture environment. Furthermore, we showed that the ablation of candidalysin expression in C. albicans reduced NETosis and conferred resistance to neutrophil-mediated fungal biofilm elimination. Our findings illustrate the role of neutrophil NETosis in modulating C. albicans biofilm persistence in an intravascular catheter, highlighting that C. albicans can benefit from reduced virulence expression to promote its persistence in an intravascular catheter.


Asunto(s)
Biopelículas , Candida albicans , Candidiasis , Infecciones Relacionadas con Catéteres , Trampas Extracelulares , Proteínas Fúngicas , Neutrófilos , Humanos , Biopelículas/crecimiento & desarrollo , Proteínas Fúngicas/metabolismo , Candidiasis/microbiología , Candidiasis/inmunología , Infecciones Relacionadas con Catéteres/microbiología , Neutrófilos/inmunología , Neutrófilos/metabolismo , Trampas Extracelulares/inmunología , Catéteres/microbiología , Regulación Fúngica de la Expresión Génica
4.
J Biol Chem ; 300(7): 107466, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38876302

RESUMEN

Glycosaminoglycan (GAG) lyases are often strictly substrate specific, and it is especially difficult to simultaneously degrade GAGs with different types of glycosidic bonds. Herein, we found a new class of GAG lyases (GAGases) from different bacteria. These GAGases belong to polysaccharide lyase 35 family and share quite low homology with the identified GAG lyases. The most surprising thing is that GAGases can not only degrade three types of GAGs: hyaluronan, chondroitin sulfate, and heparan sulfate but also even one of them can also degrade alginate. Further investigation of structural preferences revealed that GAGases selectively act on GAG domains composed of non/6-O-/N-sulfated hexosamines and d-glucoronic acids as well as on alginate domains composed of d-mannuronic acids. In addition, GAG lyases were once speculated to have evolved from alginate lyases, but no transitional enzymes have been found. The discovery of GAGases not only broadens the category of GAG lyases, provides new enzymatic tools for the structural and functional studies of GAGs with specific structures, but also provides candidates for the evolution of GAG lyases.


Asunto(s)
Glicosaminoglicanos , Polisacárido Liasas , Especificidad por Sustrato , Glicosaminoglicanos/metabolismo , Glicosaminoglicanos/química , Polisacárido Liasas/metabolismo , Polisacárido Liasas/química , Proteínas Bacterianas/química , Proteínas Bacterianas/metabolismo , Proteínas Bacterianas/genética , Sulfatos de Condroitina/metabolismo , Sulfatos de Condroitina/química
5.
Development ; 149(12)2022 06 15.
Artículo en Inglés | MEDLINE | ID: mdl-35616329

RESUMEN

The perinuclear theca (PT) is a cytoskeletal element encapsulating the sperm nucleus; however, the physiological roles of the PT in sperm are largely uncertain. Here, we reveal that ACTRT1, ACTRT2, ACTL7A and ACTL9 proteins interact to form a multimeric complex and localize to the subacrosomal region of spermatids. Furthermore, we engineered Actrt1-knockout (KO) mice to define the functions of ACTRT1. Despite normal sperm count and motility, Actrt1-KO males were severely subfertile owing to a deficiency in fertilization. Loss of ACTRT1 caused a high incidence of malformed heads and detachment of acrosomes from sperm nuclei, caused by loosened acroplaxome structure during spermiogenesis. Furthermore, Actrt1-KO sperm showed reduced ACTL7A and PLCζ protein content as a potential cause of fertilization defects. Moreover, we reveal that ACTRT1 anchors developing acrosomes to the nucleus, likely by interacting with the inner acrosomal membrane protein SPACA1 and the nuclear envelope proteins PARP11 and SPATA46. Loss of ACTRT1 weakened the interaction between ACTL7A and SPACA1. Our study and recent findings of ACTL7A/ACTL9-deficient sperm together reveal that the sperm PT-specific ARP complex mediates the acrosome-nucleus connection.


Asunto(s)
Acrosoma , Infertilidad Masculina , Acrosoma/metabolismo , Animales , Humanos , Infertilidad Masculina/genética , Infertilidad Masculina/metabolismo , Masculino , Proteínas de la Membrana/metabolismo , Ratones , Ratones Noqueados , Proteínas de Microfilamentos/metabolismo , Espermátides/metabolismo , Espermatogénesis/genética , Espermatozoides/metabolismo
6.
Development ; 149(22)2022 11 15.
Artículo en Inglés | MEDLINE | ID: mdl-36264221

RESUMEN

The evolutionarily conserved Glycogen Synthase Kinase 3ß (GSK3ß), a negative regulator of microtubules, is crucial for neuronal polarization, growth and migration during animal development. However, it remains unknown whether GSK3ß regulates neuronal pruning, which is a regressive process. Here, we report that the Drosophila GSK3ß homologue Shaggy (Sgg) is cell-autonomously required for dendrite pruning of ddaC sensory neurons during metamorphosis. Sgg is necessary and sufficient to promote microtubule depolymerization, turnover and disassembly in the dendrites. Although Sgg is not required for the minus-end-out microtubule orientation in dendrites, hyperactivated Sgg can disturb the dendritic microtubule orientation. Moreover, our pharmacological and genetic data suggest that Sgg is required to promote dendrite pruning at least partly via microtubule disassembly. We show that Sgg and Par-1 kinases act synergistically to promote microtubule disassembly and dendrite pruning. Thus, Sgg and Par-1 might converge on and phosphorylate a common downstream microtubule-associated protein(s) to disassemble microtubules and thereby facilitate dendrite pruning.


Asunto(s)
Proteínas de Drosophila , Drosophila , Animales , Drosophila/genética , Proteínas de Drosophila/genética , Glucógeno Sintasa Quinasa 3 beta/genética , Dendritas/genética , Células Receptoras Sensoriales , Microtúbulos , Plasticidad Neuronal/genética , Drosophila melanogaster/genética
7.
Methods ; 222: 112-121, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38215898

RESUMEN

Design of molecules for candidate compound selection is one of the central challenges in drug discovery due to the complexity of chemical space and requirement of multi-parameter optimization. Here we present an application scenario-oriented platform (ID4Idea) for molecule generation in different scenarios of drug discovery. This platform utilizes both library or rule based and generative based algorithms (VAE, RNN, GAN, etc.), in combination with various AI learning types (pre-training, transfer learning, reinforcement learning, active learning, etc.) and input representations (1D SMILES, 2D graph, 3D shape, binding site, pharmacophore, etc.), to enable customized solutions for a given molecular design scenario. Besides the usual generation followed screening protocol, goal-directed molecule generation can also be conducted towards predefined goals, enhancing the efficiency of hit identification, lead finding, and lead optimization. We demonstrate the effectiveness of ID4Idea platform through case studies, showcasing customized solutions for different design tasks using various input information, such as binding pockets, pharmacophores, and compound representations. In addition, remaining challenges are discussed to unlock the full potential of AI models in drug discovery and pave the way for the development of novel therapeutics.


Asunto(s)
Diseño de Fármacos , Descubrimiento de Drogas , Sitios de Unión , Algoritmos , Biblioteca de Genes
8.
J Biol Chem ; 299(5): 104692, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-37031818

RESUMEN

Chondroitinase ABC-type I (CSase ABC I), which can digest both chondroitin sulfate (CS) and dermatan sulfate (DS) in an endolytic manner, is an essential tool in structural and functional studies of CS/DS. Although a few CSase ABC I have been identified from bacteria, the substrate-degrading pattern and regulatory mechanisms of them have rarely been investigated. Herein, two CSase ABC I, IM3796 and IM1634, were identified from the intestinal metagenome of CS-fed mice. They show high sequence homology (query coverage: 88.00%, percent identity: 90.10%) except for an extra peptide (Met1-His109) at the N-terminus in IM1634, but their enzymatic properties are very different. IM3796 prefers to degrade 6-O-sulfated GalNAc residue-enriched CS into tetra- and disaccharides. In contrast, IM1634 exhibits nearly a thousand times more activity than IM3796 and can completely digest CS/DS with various sulfation patterns to produce disaccharides, unlike most CSase ABC I. Structure modeling showed that IM3796 did not contain an N-terminal domain composed of two ß-sheets, which is found in IM1634 and other CSase ABC I. Furthermore, deletion of the N-terminal domain (Met1-His109) from IM1634 caused the enzymatic properties of the variant IM1634-T109 to be similar to those of IM3796, and conversely, grafting this domain to IM3796 increased the similarity of the variant IM3796-A109 to IM1634. In conclusion, the comparative study of the new CSase ABC I provides two unique tools for CS/DS-related studies and applications and, more importantly, reveals the critical role of the N-terminal domain in regulating the substrate binding and degradation of these enzymes.


Asunto(s)
Condroitina ABC Liasa , Sulfatos de Condroitina , Animales , Ratones , Bacterias/enzimología , Condroitina ABC Liasa/química , Sulfatos de Condroitina/metabolismo , Dermatán Sulfato/química , Disacáridos/química , Péptidos , Especificidad por Sustrato
9.
J Gene Med ; 26(1): e3569, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37533324

RESUMEN

BACKGROUND: Cholangiocarcinoma is a prevalent gastrointestinal tumor with limited effective early diagnostic methods. The role of neutrophils in the context of cholangiocarcinoma remains largely unexplored. METHODS: A comprehensive analysis was performed on a cohort of cholangiocarcinoma samples (TCGA-CHOL) from the TCGA database to investigate the relationship between cholangiocarcinoma and neutrophils. Methodologies included single-sample gene set enrichment analysis (ssGSEA), differential expression analysis, weighted gene co-expression network analysis (WGCNA) and gene set enrichment analysis (GSEA). RESULTS: The study identified a significant decrease of neutrophils in cholangiocarcinoma via ssGSEA. WGCNA and differential expression analysis led to the identification of a neutrophil-related gene module comprised of 1059 genes. Cluster 1, showing a higher proportion of neutrophils, was linked to better survival outcomes. GSEA disclosed downregulation of complement, inflammatory response and interferon response pathways in Cluster 2, hinting at possible cholangiocarcinoma development triggers. A notable upregulation of PD1, PD-L1 and CTLA4 was observed in Cluster 1, suggesting potential benefits from immunotherapy. A prognostic model was developed based on clinical data and expression levels of three prognostic genes (SOWAHD, TNFAIP8 and EBF3) showing satisfactory discrimination, calibration and clinical benefits. An overexpression of TNFAIP8 in cholangiocarcinoma cells was found, with its knockdown significantly inhibiting cell proliferation and migration. CONCLUSIONS: This study elucidates a neutrophil-related gene module and prognostic genes, offering insights into the role of neutrophils in cholangiocarcinoma development and progression. It also introduces a clinical prediction model for enhanced prognosis assessment. These findings may lay the groundwork for the development of innovative therapeutic strategies in cholangiocarcinoma treatment.


Asunto(s)
Neoplasias de los Conductos Biliares , Colangiocarcinoma , Humanos , Pronóstico , Neutrófilos , Modelos Estadísticos , Colangiocarcinoma/diagnóstico , Colangiocarcinoma/genética , Neoplasias de los Conductos Biliares/genética , Conductos Biliares Intrahepáticos , Factores de Transcripción
10.
J Virol ; 97(3): e0143322, 2023 03 30.
Artículo en Inglés | MEDLINE | ID: mdl-36916989

RESUMEN

Cathelicidin antimicrobial peptides (mouse, CRAMP; human, LL-37) have broad-spectrum antiviral activities against enveloped viruses, but their mechanisms of action against nonenveloped viruses remain to be elucidated. Coxsackievirus B3 (CVB3), a member of nonenveloped virus belonging to the Enterovirus genus of Picornaviridae, is an important pathogen of viral myocarditis and dilated cardiomyopathy. Here, we observed that cardiac CRAMP expression was significantly upregulated in mice after CVB3 infection. The administration of CRAMP or LL-37 markedly suppressed CVB3 infection in mice, and CRAMP deficiency increased the susceptibility of mice to CVB3. CRAMP and LL-37 inhibited CVB3 replication in primary cardiomyocytes. However, they did not inactivate CVB3 particles and did not regulate the response of cardiomyocytes against CVB3 infection. Intriguingly, they inhibited CVB3 transmission through the exosome, but not virus receptor. In detail, CRAMP and LL-37 directly induced the lysis of exosomes by interfering with exosomal heat shock protein 60 (HSP60) and then blocked the diffusion of exosomes to recipient cells and inhibited the establishment of productive infection by exosomes. In addition, the interaction of CRAMP and LL-37 with HSP60 simultaneously inhibited HSP60-induced apoptosis in cardiomyocytes and reduced HSP60-enhanced CVB3 replication. Our findings reveal a novel mechanism of cathelicidins against viral infection and provide a new therapeutic strategy for CVB3-induced viral myocarditis. IMPORTANCE The relative mechanisms that cathelicidin antimicrobial peptides use to influence nonenveloped virus infection are unclear. We show here that cathelicidin antimicrobial peptides (CRAMP and LL-37) directly target exosomal HSP60 to destroy exosomes, which in turn block the diffusion of exosomes to recipient cardiomyocytes and reduced HSP60-induced apoptosis, thus restricting coxsackievirus B3 infection. Our results provide new insights into the mechanisms cathelicidin antimicrobial peptides use against viral infection.


Asunto(s)
Catelicidinas , Infecciones por Coxsackievirus , Exosomas , Miocitos Cardíacos , Animales , Humanos , Ratones , Apoptosis/efectos de los fármacos , Catelicidinas/administración & dosificación , Chaperonina 60/antagonistas & inhibidores , Infecciones por Coxsackievirus/tratamiento farmacológico , Enterovirus Humano B/fisiología , Exosomas/efectos de los fármacos , Miocarditis , Miocitos Cardíacos/efectos de los fármacos , Replicación Viral
11.
J Transl Med ; 22(1): 514, 2024 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-38812032

RESUMEN

The aging process of the kidneys is accompanied with several structural diseases. Abnormal fiber formation disrupts the balance of kidney structure and function, causing to end-stage renal disease and subsequent renal failure. Despite this, the precise mechanism underlying renal damage in aging remains elusive. In this study, ABI3BP gene knockout mice were used to investigate the role of ABI3BP in renal aging induced by irradiation. The results revealed a significant increase in ABI3BP expression in HK2 cells and kidney tissue of aging mice, with ABI3BP gene knockout demonstrating a mitigating effect on radiation-induced cell aging. Furthermore, the study observed a marked decrease in Klotho levels and an increase in ferroptosis in renal tissue and HK2 cells following irradiation. Notably, ABI3BP gene knockout not only elevated Klotho expression but also reduced ferroptosis levels. A significant negative correlation between ABI3BP and Klotho was established. Further experiments demonstrated that Klotho knockdown alleviated the aging inhibition caused by ABI3BP downregulation. This study identifies the upregulation of ABI3BP in aged renal tubular epithelial cells, indicating a role in promoting ferroptosis and inducing renal aging by inhibiting Klotho expression.


Asunto(s)
Envejecimiento , Ferroptosis , Riñón , Proteínas Klotho , Ratones Noqueados , Animales , Humanos , Masculino , Ratones , Envejecimiento/metabolismo , Proteínas Portadoras/metabolismo , Proteínas Portadoras/genética , Línea Celular , Glucuronidasa/metabolismo , Riñón/metabolismo , Riñón/patología , Proteínas Klotho/metabolismo , Ratones Endogámicos C57BL
12.
BMC Microbiol ; 24(1): 62, 2024 Feb 19.
Artículo en Inglés | MEDLINE | ID: mdl-38373936

RESUMEN

BACKGROUND: In this study, we investigated the effects of alpine meadow in different phenological periods on ruminal fermentation, serum biochemical indices, and gastrointestinal tract microbes in grazing yak on the Qinghai-Tibetan Plateau. A total of eighteen female freely grazing yaks with an average age of 3 years old and a body weight of 130 ± 19 kg were selected. According to the plant phenological periods, yaks were randomly allocated to one of three treatments: (1) regreen periods group (RP, n = 6); (2) grassy periods group (GP, n = 6); and (3) hay periods group (HP, n = 6). At the end of the experiment, the blood, rumen fluids, and rectal contents were collected to perform further analysis. RESULTS: The concentrations of total volatile fatty acid (TVFA), acetate, glucose (GLU), triglyceride (TG), cholesterol (CHO), high density lipoprotein (HDL), and low density lipoprotein (LDL) were higher in the GP group than in the HP group (P < 0.05). However, compared with the RP and GP groups, the HP group had higher concentrations of isobutyrate, isovalerate, valerate, and creatinine (CREA) (P < 0.05). The abundance of Prevotella in the rumen, and the abundances of Rikenellaceae_RC9_gut_group, Eubacterium_coprostanoligenes_group, and Prevotellaceae_UCG-004 in the gut were higher in the GP group compared with the HP group (P < 0.05). The HP had higher abundance of Eubacterium_coprostanoligenes_group in the rumen as well as the abundances of Romboutsia and Arthrobacter in the gut compared with the RP and GP groups (P < 0.05). CONCLUSIONS: Based on the results of rumen fermentation, serum biochemical, differential biomarkers, and function prediction, the carbohydrate digestion of grazing yak would be higher with the alpine meadow regreen and grassy due to the gastrointestinal tract microbes. However, the risk of microbe disorders and host inflammation in grazing yak were higher with the alpine meadow wither.


Asunto(s)
Pradera , Rumen , Animales , Bovinos , Bacterias/genética , Bacteroidetes , Fermentación , Tracto Gastrointestinal , Rumen/microbiología , Tibet
13.
Bioconjug Chem ; 35(3): 277-285, 2024 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-38417023

RESUMEN

Peptides and proteins undergo crucial modifications to alter their physicochemical properties to expand their applications in diverse fields. Various techniques, such as unnatural amino acid incorporation, enzyme catalysis, and chemoselective methods, have been employed for site-selective peptide and protein modification. While traditional methods remain valuable, advancement in host-guest chemistry introduces innovative and promising approaches for the selective modification of peptides and proteins. Macrocycles exhibit robust binding affinities, particularly with natural amino acids, which facilitates their use in selectively binding to specific sequences. This distinctive property endows macrocycles with the potential for modification of target peptides and proteins. This review provides a comprehensive overview of strategies utilizing macrocycles for the selective modification of peptides and proteins. These strategies unlock new possibilities for constructing antibody-drug conjugates and stabilizing volatile medications.


Asunto(s)
Péptidos , Proteínas , Péptidos/química , Proteínas/química , Aminoácidos/química , Procesamiento Proteico-Postraduccional
14.
Bioconjug Chem ; 35(1): 107-114, 2024 01 17.
Artículo en Inglés | MEDLINE | ID: mdl-38108270

RESUMEN

We herein described the design and synthesis of the cyanopyridoimidazoles (CPIs) as new bioorthogonal click reagents toward 1,2-aminothiol groups. Kinetic and density functional theory-based studies of the synthetic compounds revealed that incorporating an electron-withdrawing substituent into the CPI scaffold lowers its lowest unoccupied molecular orbital energy, consequently increasing reactivity. Optimized CPI 8a showed rapid reactivity and high stability in physiological conditions and has been demonstrated to be suitable for various radiotracer synthetic methods. Based on the new bioorthogonal reaction, a [67Ga]Ga-labeled prostate-specific membrane antigen-targeted probe was successfully prepared for in vivo imaging of prostate cancer in an animal model.


Asunto(s)
Neoplasias de la Próstata , Humanos , Masculino , Animales , Radiofármacos , Química Clic , Reacción de Cicloadición
15.
Microb Pathog ; 194: 106841, 2024 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-39117013

RESUMEN

Multi-resistant Staphylococcus aureus (S. aureus) infection is a significant global health concern owing to its high mortality and morbidity rates. Coagulase (Coa), a key enzyme that activates prothrombin to initiate host coagulation, has emerged as a promising target for anti-infective therapeutic approaches. This study identified sinigrin as a potent Coa inhibitor that significantly inhibited S. aureus-induced coagulation at concentration as low as 32 mg/L. Additionally, at a higher concentration of 128 mg/L, sinigrin disrupted the self-protection mechanism of S. aureus. Thermal shift and fluorescence-quenching assays confirmed the direct binding of sinigrin to the Coa protein. Molecular docking analysis predicted specific binding sites for sinigrin in the Coa molecule, and point mutation experiments highlighted the importance of Arg-187 and Asp-222 as critical binding sites for both Coa and sinigrin. In vivo studies demonstrated that the combination of sinigrin with oxacillin exhibited greater antibacterial efficacy than oxacillin alone in the treatment of S. aureus-induced pneumonia in mice. Furthermore, sinigrin was shown to reduce bacterial counts and inflammatory cytokine levels in the lung tissues of S. aureus-infected mice. In summary, sinigrin was shown to directly target Coa, resulting in the attenuation of S. aureus virulence, which suggests the potential of sinigrin as an adjuvant for future antimicrobial therapies.

16.
Dev Growth Differ ; 66(2): 133-144, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38281811

RESUMEN

Macrophages play a pivotal role in the response to injury, contributing significantly to the repair and regrowth of damaged tissues. The external lateral line system in aquatic organisms offers a practical model for studying regeneration, featuring interneuromast cells connecting sensory neuromasts. Under normal conditions, these cells remain dormant, but their transformation into neuromasts occurs when overcoming inhibitory signals from Schwann cells and posterior lateral line nerves. The mechanism enabling interneuromast cells to evade inhibition by Schwann cells remains unclear. Previous observations suggest that macrophages physically interact with neuromasts, nerves, and Schwann cells during regeneration. This interaction leads to the regeneration of neuromasts in a subset of zebrafish with ablated neuromasts. To explore whether macrophages achieve this effect through secreted cytokines, we conducted experiments involving tail amputation in zebrafish larvae and tested the impact of cytokine inhibitors on neuromast regeneration. Most injured larvae remarkably regenerated a neuromast within 4 days post-amputation. Intriguingly, removal of macrophages and inhibition of the anti-inflammatory cytokine transforming growth factor-beta (TGF-ß) significantly delayed neuromast regeneration. Conversely, inhibition of the pro-inflammatory cytokines interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-α) had minor effects on the regeneration process. This study provides insights into how macrophages activate interneuromast cells, elucidating the pathways underlying neuromast regeneration.


Asunto(s)
Sistema de la Línea Lateral , Pez Cebra , Animales , Pez Cebra/fisiología , Factor de Crecimiento Transformador beta/farmacología
17.
Langmuir ; 2024 Feb 06.
Artículo en Inglés | MEDLINE | ID: mdl-38320286

RESUMEN

All-inorganic perovskite solar cells (PSCs) have recently received increasing attention due to their outstanding thermal stability. However, the performance of these devices, especially for the devices with a p-i-n structure, is still inferior to that of the typical organic-inorganic counterparts. In this study, we introduce phenylammonium iodides with different side groups on the surface of the CsPbI2Br perovskite film and investigate their passivation effects. Our studies indicate that the 4-trifluoromethyl phenylammonium iodide (CFPA) molecule with the -CF3 side group effectively decreases the trap density of the perovskite film by forming interactions with the undercoordinated Pb2+ ions and significantly inhibits the nonradiative recombination in the derived PSC, leading to an enhanced open-circuit voltage (Voc) from 0.96 to 1.10 V after passivation. Also, the CFPA post-treatment enables better energy-level alignment between the conduction band minimum of CsPbI2Br perovskite and [6,6]-phenyl C61 butyric acid methyl ester, thereby enhancing the charge extraction from the perovskite to the charge transport layer. These combined benefits result in a significant enhancement of the power conversion efficiency from 11.22 to 14.37% for inverted CsPbI2Br PSCs. The device without encapsulation exhibits a degradation of only ≈4% after 1992 h in a N2 glovebox.

18.
J Org Chem ; 89(6): 4249-4260, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38443760

RESUMEN

The Minisci-type dehydrogenative coupling of N-heteroaromatic rings with inert C-H or Si-H partners via visible-light-catalyzed hydrogen atom transfer has been reported. This methodology allows the coupling reactions to be carried out in water as a solvent under air atmospheric conditions with visible-light illumination. A wide range of inert C-H and Si-H partners could be directly coupled with various N-aromatic heterocycles to deliver products in good to excellent yields.

19.
J Org Chem ; 89(12): 9098-9102, 2024 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-38861461

RESUMEN

We report the first total synthesis of scleropentaside D, a unique C-glycosidic ellagitannin, from the ketal derivative of scleropentaside A employing site-selective O4-protection of C-acyl glycoside and copper-catalyzed oxidative coupling reaction of galloyl groups as the key steps. Our study confirms the proposed structure of this natural product, scleropentaside D, and demonstrates its effectiveness as an inhibitor of α-glycosidase.


Asunto(s)
Taninos Hidrolizables , Taninos Hidrolizables/química , Taninos Hidrolizables/farmacología , Taninos Hidrolizables/síntesis química , Estructura Molecular , Glicósidos/química , Glicósidos/síntesis química , Glicósidos/farmacología , Glicósido Hidrolasas/antagonistas & inhibidores , Inhibidores Enzimáticos/síntesis química , Inhibidores Enzimáticos/farmacología , Inhibidores Enzimáticos/química , Catálisis
20.
J Vasc Interv Radiol ; 35(5): 780-789.e1, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38355040

RESUMEN

PURPOSE: To validate the sensitivity and specificity of a 3-dimensional (3D) convolutional neural network (CNN) artificial intelligence (AI) software for lung lesion detection and to establish concordance between AI-generated needle paths and those used in actual biopsy procedures. MATERIALS AND METHODS: This was a retrospective study using computed tomography (CT) scans from 3 hospitals. Inclusion criteria were scans with 1-5 nodules of diameter ≥5 mm; exclusion criteria were poor-quality scans or those with nodules measuring <5mm in diameter. In the lesion detection phase, 2,147 nodules from 219 scans were used to develop and train the deep learning 3D-CNN to detect lesions. The 3D-CNN was validated with 235 scans (354 lesions) for sensitivity, specificity, and area under the receiver operating characteristic curve (AUC) analysis. In the path planning phase, Bayesian optimization was used to propose possible needle trajectories for lesion biopsy while avoiding vital structures. Software-proposed needle trajectories were compared with actual biopsy path trajectories from intraprocedural CT scans in 150 patients, with a match defined as an angular deviation of <5° between the 2 trajectories. RESULTS: The model achieved an overall AUC of 97.4% (95% CI, 96.3%-98.2%) for lesion detection, with mean sensitivity of 93.5% and mean specificity of 93.2%. Among the software-proposed needle trajectories, 85.3% were feasible, with 82% matching actual paths and similar performance between supine and prone/oblique patient orientations (P = .311). The mean angular deviation between matching trajectories was 2.30° (SD ± 1.22); the mean path deviation was 2.94 mm (SD ± 1.60). CONCLUSIONS: Segmentation, lesion detection, and path planning for CT-guided lung biopsy using an AI-guided software showed promising results. Future integration with automated robotic systems may pave the way toward fully automated biopsy procedures.


Asunto(s)
Aprendizaje Profundo , Biopsia Guiada por Imagen , Valor Predictivo de las Pruebas , Programas Informáticos , Tomografía Computarizada por Rayos X , Humanos , Estudios Retrospectivos , Reproducibilidad de los Resultados , Biopsia Guiada por Imagen/métodos , Femenino , Masculino , Persona de Mediana Edad , Neoplasias Pulmonares/patología , Neoplasias Pulmonares/diagnóstico por imagen , Anciano , Interpretación de Imagen Radiográfica Asistida por Computador , Teorema de Bayes , Biopsia con Aguja , Pulmón/diagnóstico por imagen , Pulmón/patología
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