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In mammals, NLRX1 is a unique member of the nucleotide-binding domain and leucine-rich repeat (NLR) family showing an ability to negatively regulate IFN antiviral immunity. Intron-containing genes, including NLRX1, have more than one transcript due to alternative splicing; however, little is known about the function of its splicing variants. Here, we identified a transcript variant of NLRX1 in zebrafish (Danio rerio), termed NLRX1-tv4, as a negative regulator of fish IFN response. Zebrafish NLRX1-tv4 was slightly induced by viral infection, with an expression pattern similar to the full-length NLRX1. Despite the lack of an N-terminal domain that exists in the full-length NLRX1, overexpression of NLRX1-tv4 still impaired fish IFN antiviral response and promoted viral replication in fish cells, similar to the full-length NLRX1. Mechanistically, NLRX1-tv4 targeted STING for proteasome-dependent protein degradation by recruiting an E3 ubiquitin ligase RNF5 to drive the K48-linked ubiquitination, eventually downregulating the IFN antiviral response. Mapping of NLRX1-tv4 domains showed that its N-terminal and C-terminal regions exhibited a similar potential to inhibit STING-mediated IFN antiviral response. Our findings reveal that like the full-length NLRX1, zebrafish NLRX-tv4 functions as an inhibitor to shape fish IFN antiviral response.IMPORTANCEIn this study, we demonstrate that a transcript variant of zebrafish NLRX1, termed NLRX1-tv4, downregulates fish IFN response and promotes virus replication by targeting STING for protein degradation and impairing the interaction of STING and TBK1 and that its N- and C-terminus exhibit a similar inhibitory potential. Our results are helpful in clarifying the current contradictory understanding of structure and function of vertebrate NLRX1s.
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Proteínas de Membrana , Proteínas Mitocondriais , Proteínas de Peixe-Zebra , Animais , Imunidade Inata , Domínios Proteicos , Isoformas de Proteínas/genética , Ubiquitina-Proteína Ligases , Ubiquitinação , Peixe-Zebra/imunologia , Peixe-Zebra/metabolismo , Proteínas Mitocondriais/metabolismo , Proteínas de Peixe-Zebra/metabolismo , Proteínas de Membrana/metabolismo , Interferons/metabolismoRESUMO
BACKGROUND: Imatinib has become an exceptionally effective targeted drug for treating gastrointestinal stromal tumors (GISTs). Despite its efficacy, the resistance to imatinib is common in GIST patients, posing a significant challenge to the effective treatment. METHODS: The expression profiling of TRIM21, USP15, and ACSL4 in GIST patients was evaluated using Western blot and immunohistochemistry. To silence gene expression, shRNA was utilized. Biological function of TRIM21, USP15, and ACSL4 was examined through various methods, including resistance index calculation, colony formation, shRNA interference, and xenograft mouse model. The molecular mechanism of TRIM21 and USP15 in GIST was determined by conducting Western blot, co-immunoprecipitation, and quantitative real-time PCR (qPCR) analyses. RESULTS: Here we demonstrated that downregulation of ACSL4 is associated with imatinib (IM) resistance in GIST. Moreover, clinical data showed that higher levels of ACSL4 expression are positively correlated with favorable clinical outcomes. Mechanistic investigations further indicated that the reduced expression of ACSL4 in GIST is attributed to excessive protein degradation mediated by the E3 ligase TRIM21 and the deubiquitinase USP15. CONCLUSION: These findings demonstrate that the TRIM21 and USP15 control ACSL4 stability to maintain the IM sensitive/resistant status of GIST.
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Antineoplásicos , Neoplasias Gastrointestinais , Tumores do Estroma Gastrointestinal , Humanos , Animais , Camundongos , Mesilato de Imatinib/farmacologia , Mesilato de Imatinib/uso terapêutico , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Tumores do Estroma Gastrointestinal/tratamento farmacológico , Tumores do Estroma Gastrointestinal/genética , Tumores do Estroma Gastrointestinal/patologia , Resistencia a Medicamentos Antineoplásicos/genética , RNA Interferente Pequeno/farmacologia , Proteínas Proto-Oncogênicas c-kit/metabolismo , Linhagem Celular Tumoral , Neoplasias Gastrointestinais/tratamento farmacológico , Neoplasias Gastrointestinais/genética , Neoplasias Gastrointestinais/metabolismo , Proteases Específicas de Ubiquitina/farmacologiaRESUMO
The effective central charge (denoted by c_{eff}) is a measure of entanglement through a conformal interface, while the transmission coefficient (encoded in the coefficient c_{LR} of the two-point function of the energy-momentum tensor across the interface) is a measure of energy transmission through the interface. It has been pointed out that these two are generally different. In this Letter, we propose the inequalities, 0≤c_{LR}≤c_{eff}≤min(c_{L},c_{R}). They have the simple but important implication that the amount of energy transmission can never exceed the amount of information transmission. We verify them using the AdS/CFT correspondence, using the perturbation method, and in examples beyond holography. We also show that these inequalities are sharp by constructing a class of interfaces that saturate them.
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Quantum systems usually feature a rich multilevel structure with promising resources for developing superior quantum technologies compared with their binary counterpart. Single-shot readout of these high-dimensional quantum systems is essential for exploiting their potential. Although there have been various high-spin systems, the single-shot readout of the overall state of high-spin systems remains a challenging issue. Here we demonstrate a reliable single-shot readout of spin qutrit state in a low-temperature solid-state system utilizing a binary readout scheme. We achieve a single-shot readout of an electron spin qutrit associated with a single nitrogen-vacancy center in diamond with an average fidelity of 87.80%. We use this spin qutrit system to verify quantum contextuality, a fundamental test of quantum mechanics. We observe a violation of the noncontextual hidden variable inequality with the developed single-shot readout in contrast to the conventional binary readout. These results pave the way for developing quantum information processing based on spin qutrits.
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Concave nanocrystals stand out as a testament to the importance of the nanoscale morphology in dictating the functional properties of materials. In this report, we introduce a facile synthesis method for producing gold (Au) nanocrystals with a truncated octahedral morphology that features surface concavities (Au CNTOs). The incorporation of selenium (Se) doping into the truncated octahedral Au seeds was essential for their enlargement and the formation of concave structures. By simply adjusting the quantity of seeds, we could control the size of the nanocrystals while maintaining their distinctive morphology and surface concavity. The formation mechanism suggests that Se doping likely passivates the side faces, thereby slowing growth and promoting atomic deposition at the edges and corners. The resulting Se-doped Au CNTOs exhibited strong localized surface plasmon resonance (LSPR) absorptions in the visible spectrum and the SERS performance of their assemblies was demonstrated through crystal violet detection, reaching enhancement factors around 105. This study presents an innovative approach to synthesizing concave Au nanocrystals through the incorporation of selenium during a seeded growth process, offering insights into the strategic design of plasmonic nanostructures.
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Tripartite motif (TRIM) family proteins have come forth as important modulators of innate signaling dependent on of E3 ligase activity. Recently, several human TRIM proteins have been identified as unorthodox RNA-binding proteins by RNA interactome analyses; however, their targets and functions remain largely unknown. FTRCA1 is a crucian carp (Carassius auratus)-specific finTRIM (fish novel TRIM) member and negatively regulates the IFN antiviral response by targeting two retinoic acid-inducible gene-I (RIG-I)-like receptor (RLR) pathway molecules, that is, TANK-binding kinase 1 (TBK1) and IFN regulatory factor 7 (IRF7). In this study, we identify FTRCA1 as an RNA-binding E3 ligase and characterize the contribution of its RNA-binding activity and E3 ligase activity to fish IFN response. Besides targeting TBK1 and IRF7, FTRCA1 downregulates fish IFN response also by targeting stimulator of IFN response cGAMP interactor 1 (STING1). E3 ligase activity is required for full inhibition on the TBK1- and IRF7-mediated IFN response, but partial inhibition on the STING1-mediated IFN response. However, FTRCA1 has a general binding potential to mRNAs in vitro, it selectively binds STING1 and IRF7 mRNAs in vivo to attenuate mRNA levels, and it directly interacts with TBK1 protein to target protein degradation for downregulating the IFN response. Our results present an interesting example of a fish species-specific finTRIM protein that has acquired RNA-binding activity and E3 ligase activity to fine-tune fish IFN response.
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Fator VII , RNA , Animais , Antivirais , Proteínas de Peixes/genética , Humanos , Imunidade Inata , RNA Mensageiro , Tretinoína , Proteínas com Motivo Tripartido , Ubiquitina-Proteína LigasesRESUMO
Tight junctional complexes (TJCs) between cerebral microvascular endothelial cells (CMECs) are essential parts of the blood-brain barrier (BBB), whose regulation closely correlates to the BBB's integrity and function. hCMEC/D3 is the typical cell line used to imitate and investigate the barrier function of the BBB via the construction of an in vitro model. This study aims to investigate the protective effect of the deep-sea-derived fibrinolytic compound FGFC1 against H2O2-induced dysfunction of TJCs and to elucidate the underlying mechanism. The barrier function was shown to decline following exposure to 1 mM H2O2 in an in vitro model of hCMEC/D3 cells, with a decreasing temperature-corrected transendothelial electrical resistance (tcTEER) value. The decrease in the tcTEER value was significantly inhibited by 80 or 100 µM FGFC1, which suggested it efficiently protected the barrier integrity, allowing it to maintain its function against the H2O2-induced dysfunction. According to immunofluorescence microscopy (IFM) and quantitative real-time polymerase chain reaction (qRT-PCR), compared to the H2O2-treated group, 80~100 µM FGFC1 enhanced the expression of claudin-5 (CLDN-5) and VE-cadherin (VE-cad). And this enhancement was indicated to be mainly achieved by both up-regulation of CLDN-5 and inhibition of the down-regulation by H2O2 of VE-cad at the transcriptional level. Supported by FGFC1's molecular docking to these proteins with reasonable binding energy, FGFC1 was proved to exert a positive effect on TJCs' barrier function in hCMEC/D3 cells via targeting CLDN-5 and VE-cad. This is the first report on the protection against H2O2-induced barrier dysfunction by FGFC1 in addition to its thrombolytic effect. With CLDN-5 and VE-cad as the potential target proteins of FGFC1, this study provides evidence at the cellular and molecular levels for FGFC1's reducing the risk of bleeding transformation following its application in thrombolytic therapy for cerebral thrombosis.
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Caderinas , Células Endoteliais , Peróxido de Hidrogênio , Junções Íntimas , Humanos , Junções Íntimas/efeitos dos fármacos , Junções Íntimas/metabolismo , Linhagem Celular , Peróxido de Hidrogênio/toxicidade , Peróxido de Hidrogênio/farmacologia , Caderinas/metabolismo , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/metabolismo , Barreira Hematoencefálica/efeitos dos fármacos , Barreira Hematoencefálica/metabolismo , Fibrinolíticos/farmacologia , Claudina-5/metabolismo , Antígenos CD/metabolismo , Simulação de Acoplamento Molecular , Fatores de Crescimento de Fibroblastos/farmacologiaRESUMO
The increase of vascular wall tension can lead to endothelial injury during hypertension, but its potential mechanism remains to be studied. Our results of previous study showed that HUVECs could induce changes in HMGB1/RAGE to resist abnormal mechanical environments in pathological mechanical stretching. In this study, we applied two different kinds of mechanical tension to endothelial cells using the in vitro mechanical loading system FlexCell-5000T and focused on exploring the expression of miR-107 related pathways in HUVECs with excessive mechanical tension. The results showed that miR-107 negatively regulated the expression of the HMGB1/RAGE axis under excessive mechanical tension. Excessive mechanical stretching reduced the expression of miR-107 in HUVECs, and increased the expression of the HMGB1/RAGE axis. When miR-107 analog was transfected into HUVECs with lipo3000 reagent, the overexpression of miR-107 slowed down the increase of the HMGB1/RAGE axis caused by excessive mechanical stretching. At the same time, the overexpression of miR-107 inhibited the proliferation and migration of HUVECs to a certain extent. On the contrary, when miR-107 was silent, the proliferation and migration of HUVECs showed an upward trend. In addition, the study also showed that under excessive mechanical tension, miR-107 could regulate the expression of FGF-2 by HMGB1. In conclusion, these findings suggest that pathological mechanical stretching promote resistance to abnormal mechanical stimulation on HUVECs through miR-107/HMGB1/RAGE/FGF-2 pathway, thus promote vascular repair after endothelial injury. The suggest that miR-107 is a potential therapeutic target for hypertension.
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Proteína HMGB1 , Hipertensão , MicroRNAs , Humanos , Fator 2 de Crescimento de Fibroblastos/metabolismo , Células Endoteliais da Veia Umbilical Humana/metabolismo , Proteína HMGB1/genética , Proteína HMGB1/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Hipertensão/metabolismo , Proliferação de CélulasRESUMO
A negatively charged boron vacancy (VB-) color center in hexagonal boron nitride has recently been proposed as a promising quantum sensor due to its excellent properties. However, the spin level structure of the VB- color center is still unclear, especially for the excited state. Here we measured and confirmed the excited-state spin transitions of VB- using an optically detected magnetic resonance (ODMR) technique. The zero-field splitting of the excited state is 2.06 GHz, the transverse splitting is 93.1 MHz, and the g factor is 2.04. Moreover, negative peaks in fluorescence intensity and ODMR contrast at the level anticrossing point were observed, and they further confirmed that the spin transitions we measured came from the excited state. Our work deepens the understanding of the excited-state structure of VB- and promotes VB--based quantum sensing applications.
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In humans, four small HERCs (HERC3-6) exhibit differential degrees of antiviral activity toward HIV-1. Recently we revealed a novel member HERC7 of small HERCs exclusively in non-mammalian vertebrates and varied copies of herc7 genes in distinct fish species, raising a question of what is the exact role for a certain fish herc7 gene. Here, a total of four herc7 genes (named HERC7a-d sequentially) are identified in the zebrafish genome. They are transcriptionally induced by a viral infection, and detailed promoter analyses indicate that zebrafish herc7c is a typical interferon (IFN)-stimulated gene. Overexpression of zebrafish HERC7c promotes SVCV (spring viremia of carp virus) replication in fish cells and concomitantly downregulates cellular IFN response. Mechanistically, zebrafish HERC7c targets STING, MAVS, and IRF7 for protein degradation, thus impairing cellular IFN response. Whereas the recently-identified crucian carp HERC7 has an E3 ligase activity for the conjugation of both ubiquitin and ISG15, zebrafish HERC7c only displays the potential to transfer ubiquitin. Considering the necessity for timely regulation of IFN expression during viral infection, these results together suggest that zebrafish HERC7c is a negative regulator of fish IFN antiviral response.
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Doenças dos Peixes , Infecções por Rhabdoviridae , Animais , Humanos , Peixe-Zebra/genética , Interferons/metabolismo , Proteínas de Peixe-Zebra/metabolismo , Antivirais , UbiquitinasRESUMO
Microvessels-on-a-chip have enabled in vitro studies to closely simulate in vivo microvessel environment. However, assessing microvessel permeability, a functional measure of microvascular exchange, has not been attainable in nonpermeable microfluidic platforms. This study developed a new approach that enables permeability coefficients (Ps) to be quantified in microvessels developed in nonpermeable chip platforms by integrating avidin-biotin technology. Microvessels were developed on biotinylated fibronectin-coated microfluidic channels. Solute transport was assessed by perfusing microvessels with fluorescence-labeled avidin. Avidin molecules that crossed endothelium were captured by substrate biotin and recorded with real-time confocal images. The Ps was derived from the rate of avidin-biotin accumulation at the substrate relative to solute concentration difference across microvessel wall. Avidin tracers with different physiochemical properties were used to characterize the barrier properties of the microvessel wall. The measured baseline Ps and inflammatory mediator-induced increases in Ps and endothelial cell (EC) [Ca2+]i resembled those observed in intact microvessels. Importantly, the spatial accumulation of avidin-biotin at substrate defines the transport pathways. Glycocalyx layer is well formed on endothelium and its degradation increased transcellular transport without affecting EC junctions. This study demonstrated that in vitro microvessels developed in this simply designed microfluidics structurally possess in vivo-like glycocalyx layer and EC junctions and functionally recapitulate basal barrier properties and stimuli-induced responses observed in intact microvessels. This new approach overcomes the limitations of nonpermeable microfluidics and provides an easily executed highly reproducible in vitro microvessel model with in vivo microvessel functionality, suitable for a wide range of applications in blood and vascular research and drug development.NEW & NOTEWORTHY Our study developed a novel method that allows permeability coefficient to be measured in microvessels developed in nonpermeable microfluidic platforms using avidin-biotin technology. It overcomes the major limitation of nonpermeable microfluidic system and provides a simply designed easily executed and highly reproducible in vitro microvessel model with permeability accessibility. This model with in vivo-like endothelial junctions, glycocalyx, and permeability properties advances microfluidics in microvascular research, suitable for a wide range of biomedical and clinical applications.
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Avidina , Biotina , Permeabilidade Capilar , Dispositivos Lab-On-A-Chip , Microfluídica/métodos , Microvasos/metabolismo , Animais , Cálcio/metabolismo , Células Cultivadas , Células Endoteliais/metabolismo , Endotélio Vascular/citologia , Endotélio Vascular/metabolismo , Glicocálix/metabolismo , Microfluídica/instrumentação , Microvasos/citologia , RatosRESUMO
Patients with diabetes infected with COVID-19 have greater mortality than those without comorbidities, but the underlying mechanisms remain unknown. This study aims to identify the mechanistic interactions between diabetes and severe COVID-19. Microparticles (MPs), the cell membrane-derived vesicles released on cell activation, are largely increased in patients with diabetes. To date, many mechanisms have been postulated for increased severity of COVID-19 in patients with underlying conditions, but the contributions of excessive MPs in patients with diabetes have been overlooked. This study characterizes plasma MPs from normal human subjects and patients with type 2 diabetes in terms of amount, cell origins, surface adhesive properties, ACE2 expression, spike protein binding capacity, and their roles in SARS-CoV-2 infection. Results showed that over 90% of plasma MPs express ACE2 that binds the spike protein of SARS-CoV-2. MPs in patients with diabetes increase 13-fold in quantity and 11-fold in adhesiveness when compared with normal subjects. Perfusion of human plasma with pseudo-typed SARS-CoV-2 virus or spike protein-bound MPs into human endothelial cell-formed microvessels-on-a chip demonstrated that MPs from patients with diabetes, not normal subjects, interact with endothelium and carry SARS-CoV-2 into cells through endocytosis, providing additional virus entry pathways and enhanced infection. Results also showed a large percentage of platelet-derived tissue factor-bearing MPs in diabetic plasma, which could contribute to thrombotic complications with SARS-CoV-2 infection. This study reveals a dual role of diabetic MPs in promoting SARS-CoV-2 entry and propagating vascular inflammation. These findings provide novel mechanistic insight into the high prevalence of COVID-19 in patients with diabetes and their propensity to develop severe vascular complications.NEW & NOTEWORTHY This study provides the first evidence that over 90% of human plasma microparticles express ACE2 that binds SARS-CoV-2 S protein with high affinity. Thus, the highly elevated adhesive circulating microparticles identified in patients with diabetes not only have greater SARS-CoV-2 binding capacity but also enable additional viral entry through virus-bound microparticle-endothelium interactions and enhanced infection. These findings reveal a novel mechanistic insight into the adverse outcomes of COVID-19 in patients with diabetes.
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COVID-19 , Diabetes Mellitus Tipo 2 , Humanos , Enzima de Conversão de Angiotensina 2 , COVID-19/complicações , Diabetes Mellitus Tipo 2/complicações , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/metabolismoRESUMO
BACKGROUND AND AIMS: Alveolar echinococcosis (AE) is a lethal helminthic liver disease caused by persistent infection with Echinococcus multilocularis. Although more attention has been paid to the immunotolerance of T cells caused by E. multilocularis infection, the role of natural killer (NK) cell, a critical player in liver immunity, is seldom studied. APPROACH AND RESULTS: Here, we observed that NK cells from the blood and closed liver tissue (CLT) of AE patients expressed a higher level of inhibitory receptor TIGIT and were functionally exhausted with a lower expression of granzyme B, perforin, interferon-gamma (IFN-γ), and TNF-α. Addition of anti-TIGIT (T-cell immunoreceptor with immunoglobulin and immunoreceptor tyrosine-based inhibitory motif domain) monoclonal antibody into AE patients' peripheral blood mononuclear cell culture significantly enhanced the synthesis of IFN-γ and TNF-α by NK cells, indicating the reversion of exhausted NK cells by TIGIT blockade. In the mouse model of E. multilocularis infection, liver and splenic TIGIT+ NK cells progressively increased dependent of infection dosage and timing and were less activated and less degranulated with lower cytokine secretion. Furthermore, TIGIT deficiency or blockade in vivo inhibited liver metacestode growth, reduced liver injury, and increased the level of IFN-γ produced by liver NK cells. Interestingly, NK cells from mice with persistent chronic infection expressed a higher level of TIGIT compared to self-healing mice. To look further into the mechanisms, more regulatory CD56bright and murine CD49a+ NK cells with higher TIGIT expression existed in livers of AE patients and mice infected with E. multilocularis, respectively. They coexpressed higher surface programmed death ligand 1 and secreted more IL-10, two strong inducers to mediate the functional exhaustion of NK cells. CONCLUSIONS: Our results indicate that inhibitory receptor TIGIT is involved in NK cell exhaustion and immune escape from E. multilocularis infection.
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Equinococose/microbiologia , Receptores Imunológicos/metabolismo , Animais , Modelos Animais de Doenças , Equinococose/imunologia , Equinococose/metabolismo , Humanos , Células Matadoras Naturais/patologia , CamundongosRESUMO
Recently, mesenchymal stem cell (MSC) therapy has been suggested as an effective alternative approach for the treatment of hepatic diseases. MSCs have potential therapeutic value, because they have high self-renewal ability, are capable of multipotent differentiation, and have low immunogenicity. Furthermore, MSCs have the potential to differentiate into hepatocytes, and the therapeutic value exists in their immune-modulatory properties and secretion of trophic factors, such as growth factors and cytokines. Moreover, MSCs can suppress inflammatory responses, reduce hepatocyte apoptosis, increase hepatocyte regeneration, regress liver fibrosis, and enhance liver functionality.
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Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais , Diferenciação Celular , Hepatócitos/metabolismo , Humanos , Fígado/metabolismo , Cirrose Hepática/patologiaRESUMO
A widespread increase in intense phytoplankton blooms has been noted in lakes worldwide since the 1980s, with the summertime peak intensity amplifying in most lakes. Such blooms cause annual economic losses of multibillion USD and present a major challenge, affecting 11 out of the 17 United Nations Sustainable Development Goals. Here, we evaluate recent scientific evidence for hormetic effects of emerging contaminants and regulated pollutants on Microcystis sp., the most notorious cyanobacteria forming harmful algal blooms and releasing phycotoxins in eutrophic freshwater systems. This new evidence leads to the conclusion that pollution is linked to algal bloom intensification. Concentrations of contaminants that are considerably smaller than the threshold for toxicity enhance the formation of harmful colonies, increase the production of phycotoxins and their release into the environment, and lower the efficacy of algaecides to control algal blooms. The low-dose enhancement of microcystins is attributed to the up-regulation of a protein controlling microcystin release (McyH) and various microcystin synthetases in tandem with the global nitrogen regulator Ycf28, nonribosomal peptide synthetases, and several ATP-binding cassette transport proteins. Given that colony formation and phycotoxin production and release are enhanced by contaminant concentrations smaller than the toxicological threshold and are widely occurring in the environment, the effect of contaminants on harmful algal blooms is more prevalent than previously thought. Climate change and nutrient enrichment, known mechanisms underpinning algal blooms, are thus joined by low-level pollutants as another causal mechanism.
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Cianobactérias , Poluentes Ambientais , Microcystis , Cianobactérias/metabolismo , Poluentes Ambientais/metabolismo , Proliferação Nociva de Algas , Lagos/microbiologia , Microcistinas/metabolismo , Microcystis/metabolismoRESUMO
In order to find a convenient and stable way to trace human skin fibroblasts (HSFs) in three-dimensional tissue engineering scaffolds for a long time, in this experiment, Graphene Oxide Quantum Dots (GOQDs), Amino Graphene Quantum Dots (AGQDs) and Carboxyl Graphene Quantum Dots (CGQDs) were used as the material source for labeling HSFs. Exploring the possibility of using it as a long-term tracer of HSFs in three-dimensional tissue engineering scaffolds, the contents of the experiment are as follows: the HSFs were cultured in a cell-culture medium composed of three kinds of Graphene Quantum Dots for 24 h, respectively; (1) using Cell Counting Kit 8 (CCK8), Transwell migration chamber and Phalloidin-iFlior 488 to detect the effect of Graphene Quantum Dots on the biocompatibility of HSFs; (2) using a living cell workstation to detect the fluorescence labeling results of three kinds of Graphene Quantum Dots on HSFs, and testing the fluorescence attenuation of HSFs for 7 days; (3) the HSFs labeled with Graphene Quantum Dots were inoculated on the three-dimensional chitosan demethylcellulose sodium scaffold, and the living cell workstation was used to detect the spatial distribution of the HSFs on the three-dimensional scaffold through the fluorescence properties of the HSFs.. Experimental results: (1) the results of CCK8, Transwell migration, and FITC-Phalloidin cytoskeleton test showed that the three kinds of Graphene Quantum Dots had no effect on the biological properties of HSFs (p < 0.05); (2) the results of the fluorescence labeling experiment showed that only AGQDs could make HSFs fluorescent, and cells showed orange−red fluorescence; (3) the results of long-range tracing of HSFs which were labeled by with AGQDs showed that the fluorescence life of the HSFs were as long as 7 days; (4) The spatial distribution of HSFs can be detected on the three-dimensional scaffold based on their fluorescence properties, and the detection time can be up to 7 days.
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Quitosana , Grafite , Pontos Quânticos , Fibroblastos , Fluoresceína-5-Isotiocianato , Humanos , Faloidina , Sódio , Engenharia TecidualRESUMO
Nitrogen-vacancy color centers (NVs) in diamond have several potential applications ranging from quantum computing to data storage. However, artificial NVs are often close to the surface, which limits their spatial density and applicability. Here we demonstrate an effective and precise method for preparing deep single NVs in diamond. The method is based on a spatial-shaped femtosecond laser to overcome laser defocus in high-refractive materials, and realizes the preparation of single NVs at 95 µm. In addition, owing to the good energy distribution of the shaped laser focus, the single NVs exhibit a statistic yield of 56%±11% with excellent qualities. This processing method will contribute to the integration of color centers with emerging optical elements and high-density data storage.
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BACKGROUND: Several Rhodobacter sphaeroides have been widely applied in commercial CoQ10 production, but they have poor glucose use. Strategies for enhancing glucose use have been widely exploited in R. sphaeroides. Nevertheless, little research has focused on the role of glucose transmembrane in the improvement of production. RESULTS: There are two potential glucose transmembrane pathways in R. sphaeroides ATCC 17023: the fructose specific-phosphotransferase system (PTSFru, fruAB) and non-PTS that relied on glucokinase (glk). fruAB mutation revealed two effects on bacterial growth: inhibition at the early cultivation phase (12-24 h) and promotion since 36 h. Glucose metabolism showed a corresponding change in characteristic vs. the growth. For ΔfruAΔfruB, maximum biomass (Biomax) was increased by 44.39% and the CoQ10 content was 27.08% more than that of the WT. glk mutation caused a significant decrease in growth and glucose metabolism. Over-expressing a galactose:H+ symporter (galP) in the ΔfruAΔfruB relieved the inhibition and enhanced the growth further. Finally, a mutant with rapid growth and high CoQ10 titer was constructed (ΔfruAΔfruB/tac::galPOP) using several glucose metabolism modifications and was verified by fermentation in 1 L fermenters. CONCLUSIONS: The PTSFru mutation revealed two effects on bacterial growth: inhibition at the early cultivation phase and promotion later. Additionally, biomass yield to glucose (Yb/glc) and CoQ10 synthesis can be promoted using fruAB mutation, and glk plays a key role in glucose metabolism. Strengthening glucose transmembrane via non-PTS improves the productivity of CoQ10 fermentation.
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Proteínas de Bactérias/metabolismo , Glucose/metabolismo , Engenharia Metabólica , Rhodobacter sphaeroides/metabolismo , Ubiquinona/análogos & derivados , Proteínas de Bactérias/genética , Transporte Biológico , Biomassa , Proteínas de Ligação ao Cálcio/genética , Proteínas de Ligação ao Cálcio/metabolismo , Proteínas de Escherichia coli/genética , Fermentação , Glucoquinase/genética , Glucoquinase/metabolismo , Microbiologia Industrial , Proteínas de Transporte de Monossacarídeos/genética , Proteínas de Transporte de Monossacarídeos/metabolismo , Mutação , Proteínas Periplásmicas de Ligação/genética , Proteínas Periplásmicas de Ligação/metabolismo , Proteínas Quinases/genética , Rhodobacter sphaeroides/genética , Ubiquinona/biossínteseRESUMO
OBJECTIVE: To investigate the effects of Bushen Tiaoxue Granules and Kunling Wan, the two Chinese medicines, on vascular dysfunction and the impairment of endometrial receptivity caused by controlled ovarian hyperstimulation and its underlying mechanism. METHODS: Female Sprague Dawley rats with regular estrous cycle were enrolled and given Bushen Tiaoxue Granules or Kunling Wan by gavage for 12 days, and then, controlled ovarian hyperstimulation model was induced. We assessed endometrial microvessels, endometrial blood flow, levels of estradiol and progesterone in serum, vascular endothelial growth factor A upstream molecules estrogen and progesterone receptors in the endometrium, and pregnancy outcome. RESULTS: Pre-treatment of Bushen Tiaoxue Granules or Kunling Wan increases endometrial blood flow of controlled ovarian hyperstimulation rats, up-regulates vascular endothelial growth factor A and microvessels, improves the endometrial morphology of controlled ovarian hyperstimulation rats during implantation, decreases the super physiological concentration of estradiol and progesterone in serum, and increases the expression of vascular endothelial growth factor A upstream molecules estrogen and progesterone receptors in the endometrium. In addition, Bushen Tiaoxue Granules or Kunling Wan elevates the lysophosphatidic acid receptor 3 that participates in vascularization and increases the expression of leukemia inhibitory factor through up-regulating the expression of p53 in the endometrium, ultimately affecting pregnancy outcome. CONCLUSION: This study demonstrated Bushen Tiaoxue Granules or Kunling Wan as a potential strategy for prevention of impairment in angiogenesis and endometrial receptivity induced by controlled ovarian hyperstimulation.
Assuntos
Medicamentos de Ervas Chinesas/farmacologia , Implantação do Embrião/efeitos dos fármacos , Endométrio/irrigação sanguínea , Neovascularização Fisiológica/efeitos dos fármacos , Indução da Ovulação , Animais , Feminino , Gravidez , Ratos , Ratos Sprague-DawleyRESUMO
Immune checkpoint blockade has become a promising therapeutic approach to reverse immune cell exhaustion. Coinhibitory CD96 and T-cell immunoglobulin and ITIM domain (TIGIT), together with costimulatory CD226, bind to common ligand CD155. The balancing between three receptors fine-tunes immune responses against tumors. In this study, we investigated the expression of CD96, TIGIT, and CD226 in 55 fresh human hepatocellular carcinoma (HCC) samples, 236 paraffin-embedded HCC samples, and 20 normal human livers. The cumulative percentage, absolute count, and mean fluorescence intensity (MFI) of CD96+ NK cells are significantly increased in the intratumoral tissues of HCC and break the balance between three receptors. Human CD96+ NK cells are functionally exhausted with impaired interferon-gamma (IFN-γ) and tumor necrosis factor-alpha (TNF-α) production, high gene expression of interleukin (IL)-10 and transforming growth factor-beta 1 (TGF-ß1), and low gene expression of T-bet, IL-15, perforin, and granzyme B. In addition, blocking CD96-CD155 interaction specifically increases lysis of HepG2 cells by NK cells. HCC patients with a high level of CD96 or CD155 expression within tumor are strongly associated with deteriorating disease condition and shorter disease-free survival (DFS) and overall survival times. Patients with a higher cumulative percentage of CD96+ NK cells within tumor also exhibit shorter DFS. High plasma level of TGF-ß1 in HCC patients up-regulates CD96 expression and dynamically shifts the balance between CD96, TIGIT, and CD226 in NK cells. Blocking TGF-ß1 specifically restores normal CD96 expression and reverses the dysfunction of NK cells. Conclusion: These findings indicate that human intratumoral CD96+ NK cells are functionally exhausted and patients with higher intratumoral CD96 expression exhibit poorer clinical outcomes. Blocking CD96-CD155 interaction or TGF-ß1 restores NK cell immunity against tumors by reversing NK cell exhaustion, suggesting a possible therapeutic role of CD96 in fighting liver cancer.