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Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection has been detected in almost all organs of coronavirus disease-19 patients, although some organs do not express angiotensin-converting enzyme-2 (ACE2), a known receptor of SARS-CoV-2, implying the presence of alternative receptors and/or co-receptors. Here, we show that the ubiquitously distributed human transferrin receptor (TfR), which binds to diferric transferrin to traffic between membrane and endosome for the iron delivery cycle, can ACE2-independently mediate SARS-CoV-2 infection. Human, not mouse TfR, interacts with Spike protein with a high affinity (KD ~2.95 nM) to mediate SARS-CoV-2 endocytosis. TfR knock-down (TfR-deficiency is lethal) and overexpression inhibit and promote SARS-CoV-2 infection, respectively. Humanized TfR expression enables SARS-CoV-2 infection in baby hamster kidney cells and C57 mice, which are known to be insusceptible to the virus infection. Soluble TfR, Tf, designed peptides blocking TfR-Spike interaction and anti-TfR antibody show significant anti-COVID-19 effects in cell and monkey models. Collectively, this report indicates that TfR is a receptor/co-receptor of SARS-CoV-2 mediating SARS-CoV-2 entry and infectivity by likely using the TfR trafficking pathway.
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COVID-19 , Animales , Humanos , Ratones , Enzima Convertidora de Angiotensina 2/genética , Enzima Convertidora de Angiotensina 2/metabolismo , Peptidil-Dipeptidasa A/metabolismo , Unión Proteica , Receptores de Transferrina/genética , Receptores de Transferrina/metabolismo , SARS-CoV-2/metabolismo , Glicoproteína de la Espiga del Coronavirus/metabolismoRESUMEN
We theoretically report that high-order sideband generation (HSG) from Floquet matters driven by a strong terahertz light while engineered by weak infrared light can achieve multiple plateau HSG. The Floquet-engineering systems exhibit distinctive spectroscopic characteristics that go beyond the HSG processes in field-free band-structure systems. The spatial-temporal dynamics analyses under Floquet-Bloch and time-reversal-symmetry theories clarify the spectra and its odd-even characteristics in the HSG spectrum. Our work demonstrates the HSG of Floquet matters via Floquet engineering and indicates a promising way to extract Floquet material parameters in future experiments.
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Ischemic ulcers pose a multifaceted clinical dilemma for patients with atherosclerosis, frequently compounded by suboptimal wound healing mechanisms. The dual function of Transforming Growth Factor Beta 3 (TGF-ß3) in ischemic ulcer healing is not fully comprehended, despite its involvement in modulating inflammatory responses and tissue regeneration. The main aim of this investigation was to clarify the functions and mechanisms by which TGF-ß3 regulates inflammatory responses and promotes wound healing in patients with ischemic ulcers who have atherosclerosis. Between August 2022 and November 2023, this cross-sectional investigation was conducted on 428 patients diagnosed with atherosclerotic ischemic ulcers in Haikou, China. The expression and function of TGF-ß3 were examined throughout the different stages of wound healing, including inflammation, proliferation and remodelling. In addition to documenting patient demographics and ulcer characteristics, an analysis was conducted on biopsy samples to determine the expression of TGF-ß3, pro-inflammatory and anti-inflammatory markers. A subset of patients were administered topical TGF-ß3 in order to evaluate its therapeutic effects. The expression pattern of TGF-ß3 was found to be stage-dependent and significant, exhibiting increased levels during the phase of inflammation and reduced activity in subsequent phases. TGF-ß3 levels were found to be greater in ulcers that were larger and deeper, especially in inflammatory phase. TGF-ß3 applied topically induced discernible enhancement in ulcer healing parameters, such as reduction in ulcer depth and size. The therapeutic significance of TGF-ß3 was emphasised due to its twofold function of regulating the inflammatory environment and facilitating the regeneration of damaged tissues. Ischemic ulcer lesion healing is significantly influenced by TGF-ß3, which functions as an anti-inflammatory and pro-inflammatory mediator. Its correlation with ulcer characteristics and stages of healing suggests that it may have utility as a targeted therapeutic agent.
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Aterosclerosis , Factor de Crecimiento Transformador beta3 , Humanos , Antiinflamatorios , Estudios Transversales , Inflamación , Factor de Crecimiento Transformador beta/análisis , Factor de Crecimiento Transformador beta/metabolismo , Factor de Crecimiento Transformador beta3/uso terapéutico , Factor de Crecimiento Transformador beta3/farmacología , Úlcera , Cicatrización de HeridasRESUMEN
OBJECTIVES: To investigate the neurodevelopmental characteristics of children with autism spectrum disorder (ASD), analyze the correlation between neurodevelopmental indicators and cerebral blood flow (CBF), and explore the potential mechanisms of neurodevelopment in ASD children. METHODS: A retrospective study was conducted on 145 children aged 2-6 years with newly-diagnosed ASD. Scores from the Gesell Developmental Diagnosis Scale and the Autism Behavior Checklist (ABC) and CBF results were collected to compare gender differences in the development of children with ASD and analyze the correlation between CBF and neurodevelopmental indicators. RESULTS: Fine motor and personal-social development quotient in boys with ASD were lower than those in girls with ASD (P<0.05). Gross motor development quotient in ASD children was negatively correlated with CBF in the left frontal lobe (r=-0.200, P=0.016), right frontal lobe (r=-0.279, P=0.001), left parietal lobe (r=-0.208, P=0.012), and right parietal lobe (r=-0.187, P=0.025). The total ABC score was positively correlated with CBF in the left amygdala (r=0.295, P<0.001). CONCLUSIONS: Early intervention training should pay attention to gender and developmental structural characteristics for precise intervention in ASD children. CBF has the potential to become a biological marker for assessing the severity of ASD.
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Trastorno del Espectro Autista , Circulación Cerebrovascular , Humanos , Masculino , Trastorno del Espectro Autista/fisiopatología , Femenino , Preescolar , Niño , Estudios Retrospectivos , Desarrollo InfantilRESUMEN
Titanium alloy materials are commonly used in orthopedic clinical treatments. However, conventional titanium implants usually lead to insufficient bone regeneration and integration because of mismatched biomechanics and poor bioactivities. To tackle these challenges, a porous titanium alloy scaffold with suitable mechanical properties was prepared using three-dimensional (3D) printing, and then an adipose-derived mesenchymal stem cell (ADSC) loaded platelet-rich plasma (PRP) gel was placed into the pores of the porous scaffold to construct a bioactive scaffold with dual functions of enhancing angiogenesis and osteogenesis. This bioactive scaffold showed good biocompatibility and supported cell viability proliferation and morphology of encapsulated ADSCs. Osteogenic and angiogenic growth factors in the PRP gel promoted the migration and angiogenesis of human umbilical vein endothelial cells (HUVECs) in vitro and enhanced osteogenic-related gene and protein expression in ADSCs, thus promoting osteogenic differentiation. After implantation into the femoral defects of rabbits, the bioactive scaffold promoted vascular network formation and the expression of osteogenesis-related proteins, thus effectively accelerating bone regeneration. Therefore, the osteogenic and angiogenic bioactive scaffold comprising a 3D printed porous titanium alloy scaffold, PRP, and ADSCs provides a promising design for orthopedic biomaterials with clinical transformation prospects and an effective strategy for bone defect treatment.
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The contamination of bone defects is a serious therapeutic problem. The treatment of infected bone defects involves rigorous infection control followed by bone reconstruction. Considering these two processes, the development of biomaterials possessing antibacterial and osteogenic properties offers a promising approach for the treatment of infected bone defects. In this study, a dual-functional, thermosensitive, and injectable hydrogel composed of chitosan (CS), quaternized CS (QCS), and nano-hydroxyapatite (nHA) was designed, and the ratio of CS to QCS in the hydrogel was optimized to enhance the antibacterial efficacy of CS while reducing the cytotoxicity of QCS. In vitro studies demonstrated that the hydrogel with an 85 %:15 % ratio of CS to QCS exhibited excellent biocompatibility and antibacterial properties while also possessing suitable mechanical characteristics and degradability. The incorporation of nHA into the hydrogel enhanced MC3T3-E1 proliferation and osteogenic differentiation. Moreover, this hydrogel demonstrated superior in vivo therapeutic effectiveness in a rabbit model of infected bone defect. In summary, this study provides a promising material design and a comprehensive one-step treatment strategy for infected bone defects.
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The manipulation of microscopic objects requires precise and controllable forces and torques. Recent advances have led to the use of critical Casimir forces as a powerful tool, which can be finely tuned through the temperature of the environment and the chemical properties of the involved objects. For example, these forces have been used to self-organize ensembles of particles and to counteract stiction caused by Casimir-Liftshitz forces. However, until now, the potential of critical Casimir torques has been largely unexplored. Here, we demonstrate that critical Casimir torques can efficiently control the alignment of microscopic objects on nanopatterned substrates. We show experimentally and corroborate with theoretical calculations and Monte Carlo simulations that circular patterns on a substrate can stabilize the position and orientation of microscopic disks. By making the patterns elliptical, such microdisks can be subject to a torque which flips them upright while simultaneously allowing for more accurate control of the microdisk position. More complex patterns can selectively trap 2D-chiral particles and generate particle motion similar to non-equilibrium Brownian ratchets. These findings provide new opportunities for nanotechnological applications requiring precise positioning and orientation of microscopic objects.
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The treatment of bone defects is a difficult problem in orthopedics. The excessive destruction of local bone tissue at defect sites destroys blood supply and renders bone regeneration insufficient, which further leads to delayed union or even nonunion. To solve this problem, in this study, we incorporated icariin into alginate/mineralized collagen (AMC) hydrogel and then placed the drug-loaded hydrogel into the pores of a 3D-printed porous titanium alloy (AMCI/PTi) scaffold to prepare a bioactive scaffold with the dual functions of promoting angiogenesis and bone regeneration. The experimental results showed that the ACMI/PTi scaffold had suitable mechanical properties, sustained drug release function, and excellent biocompatibility. The released icariin and mineralized collagen (MC) synergistically promoted angiogenesis and osteogenic differentiation in vitro. After implantation into a rabbit radius defect, the composite scaffold showed a satisfactory effect in promoting bone repair. Therefore, this composite dual-functional scaffold could meet the requirements of bone defect treatment and provide a promising strategy for the repair of large segmental bone defects in clinic.
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Cross-talks (e.g., host-driven iron withdrawal and microbial iron uptake between host gastrointestinal tract and commensal microbes) regulate immunotolerance and intestinal homeostasis. However, underlying mechanisms that regulate the cross-talks remain poorly understood. Here, we show that bacterial products up-regulate iron-transporter transferrin and transferrin acts as an immunosuppressor by interacting with cluster of differentiation 14 (CD14) to inhibit pattern recognition receptor (PRR) signaling and induce host immunotolerance. Decreased intestinal transferrin is found in germ-free mice and human patients with ulcerative colitis, which are characterized by impaired intestinal immunotolerance. Intestinal transferrin and host immunotolerance are returned to normal when germ-free mice get normal microbial commensalism, suggesting an association between microbial commensalism, transferrin, and host immunotolerance. Mouse colitis models show that transferrin shortage impairs host's tolerogenic responses, while its supplementation promotes immunotolerance. Designed peptide blocking transferrin-CD14 interaction inhibits immunosuppressive effects of transferrin. In monkeys with idiopathic chronic diarrhea, transferrin shows comparable or even better therapeutic effects than hydrocortisone. Our findings reveal that by up-regulating host transferrin to silence PRR signaling, commensal bacteria counteract immune activation induced by themselves to shape host immunity and contribute for intestinal tolerance.
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Commensal bacteria generate immensely diverse active metabolites to maintain gut homeostasis, however their fundamental role in establishing an immunotolerogenic microenvironment in the intestinal tract remains obscure. Here, we demonstrate that an understudied murine commensal bacterium, Dubosiella newyorkensis, and its human homologue Clostridium innocuum, have a probiotic immunomodulatory effect on dextran sulfate sodium-induced colitis using conventional, antibiotic-treated and germ-free mouse models. We identify an important role for the D. newyorkensis in rebalancing Treg/Th17 responses and ameliorating mucosal barrier injury by producing short-chain fatty acids, especially propionate and L-Lysine (Lys). We further show that Lys induces the immune tolerance ability of dendritic cells (DCs) by enhancing Trp catabolism towards the kynurenine (Kyn) pathway through activation of the metabolic enzyme indoleamine-2,3-dioxygenase 1 (IDO1) in an aryl hydrocarbon receptor (AhR)-dependent manner. This study identifies a previously unrecognized metabolic communication by which Lys-producing commensal bacteria exert their immunoregulatory capacity to establish a Treg-mediated immunosuppressive microenvironment by activating AhR-IDO1-Kyn metabolic circuitry in DCs. This metabolic circuit represents a potential therapeutic target for the treatment of inflammatory bowel diseases.
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Colitis , Firmicutes , Quinurenina , Humanos , Animales , Ratones , Quinurenina/metabolismo , Lisina , Receptores de Hidrocarburo de Aril/metabolismo , Colitis/inducido químicamente , Bacterias/metabolismo , Tolerancia Inmunológica , Indolamina-Pirrol 2,3,-Dioxigenasa/metabolismoRESUMEN
PURPOSE: Estrogen receptor (ER) alpha signaling is a known driver of ER-positive (ER+)/human epidermal growth factor receptor 2 negative (HER2-) breast cancer. Combining endocrine therapy (ET) such as fulvestrant with CDK4/6, mTOR, or PI3K inhibitors has become a central strategy in the treatment of ER+ advanced breast cancer. However, suboptimal ER inhibition and resistance resulting from the ESR1 mutation dictates that new therapies are needed. EXPERIMENTAL DESIGN: A medicinal chemistry campaign identified vepdegestrant (ARV-471), a selective, orally bioavailable, and potent small molecule PROteolysis-TArgeting Chimera (PROTAC) degrader of ER. We used biochemical and intracellular target engagement assays to demonstrate the mechanism of action of vepdegestrant, and ESR1 wild-type (WT) and mutant ER+ preclinical breast cancer models to demonstrate ER degradation-mediated tumor growth inhibition (TGI). RESULTS: Vepdegestrant induced ≥90% degradation of wild-type and mutant ER, inhibited ER-dependent breast cancer cell line proliferation in vitro, and achieved substantial TGI (87%-123%) in MCF7 orthotopic xenograft models, better than those of the ET agent fulvestrant (31%-80% TGI). In the hormone independent (HI) mutant ER Y537S patient-derived xenograft (PDX) breast cancer model ST941/HI, vepdegestrant achieved tumor regression and was similarly efficacious in the ST941/HI/PBR palbociclib-resistant model (102% TGI). Vepdegestrant-induced robust tumor regressions in combination with each of the CDK4/6 inhibitors palbociclib, abemaciclib, and ribociclib; the mTOR inhibitor everolimus; and the PI3K inhibitors alpelisib and inavolisib. CONCLUSIONS: Vepdegestrant achieved greater ER degradation in vivo compared with fulvestrant, which correlated with improved TGI, suggesting vepdegestrant could be a more effective backbone ET for patients with ER+/HER2- breast cancer.
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Neoplasias de la Mama , Quinasa 4 Dependiente de la Ciclina , Quinasa 6 Dependiente de la Ciclina , Transducción de Señal , Serina-Treonina Quinasas TOR , Ensayos Antitumor por Modelo de Xenoinjerto , Humanos , Femenino , Animales , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/patología , Neoplasias de la Mama/metabolismo , Quinasa 6 Dependiente de la Ciclina/antagonistas & inhibidores , Quinasa 4 Dependiente de la Ciclina/antagonistas & inhibidores , Ratones , Serina-Treonina Quinasas TOR/metabolismo , Serina-Treonina Quinasas TOR/antagonistas & inhibidores , Línea Celular Tumoral , Transducción de Señal/efectos de los fármacos , Receptor alfa de Estrógeno/metabolismo , Receptor alfa de Estrógeno/genética , Receptor alfa de Estrógeno/antagonistas & inhibidores , Piperazinas/farmacología , Piperazinas/administración & dosificación , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/farmacología , Inhibidores de las Quinasa Fosfoinosítidos-3/farmacología , Inhibidores de las Quinasa Fosfoinosítidos-3/administración & dosificación , Receptores de Estrógenos/metabolismo , Piridinas/administración & dosificación , Piridinas/farmacología , Inhibidores de Proteínas Quinasas/farmacología , Proliferación Celular/efectos de los fármacosRESUMEN
Diabetic cardiomyopathy (DCM), one of the common complications of diabetes, presents as a specific cardiomyopathy with anomalies in the structure and function of the heart. With the increasing prevalence of diabetes, DCM has a high morbidity and mortality worldwide. Recent studies have found that pyroptosis, as a programmed cell death accompanied by an inflammatory response, exacerbates the growth and genesis of DCM. These studies provide a theoretical basis for exploring the potential treatment of DCM. Therefore, this review aims to summarise the possible mechanisms by which pyroptosis promotes the development of DCM as well as the relevant studies targeting pyroptosis for the possible treatment of DCM, focusing on the molecular mechanisms of NLRP3 inflammasome-mediated pyroptosis, different cellular pyroptosis pathways associated with DCM, the effects of pyroptosis occurring in different cells on DCM, and the relevant drugs targeting NLRP3 inflammasome/pyroptosis for the treatment of DCM. This review might provide a fresh perspective and foundation for the development of therapeutic agents for DCM.