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The elucidation of protein function and its exploitation in bioengineering have greatly advanced the life sciences. Protein mining efforts generally rely on amino acid sequences rather than protein structures. We describe here the use of AlphaFold2 to predict and subsequently cluster an entire protein family based on predicted structure similarities. We selected deaminase proteins to analyze and identified many previously unknown properties. We were surprised to find that most proteins in the DddA-like clade were not double-stranded DNA deaminases. We engineered the smallest single-strand-specific cytidine deaminase, enabling efficient cytosine base editor (CBE) to be packaged into a single adeno-associated virus (AAV). Importantly, we profiled a deaminase from this clade that edits robustly in soybean plants, which previously was inaccessible to CBEs. These discovered deaminases, based on AI-assisted structural predictions, greatly expand the utility of base editors for therapeutic and agricultural applications.
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Edición Génica , Proteínas , Proteínas/metabolismo , Citidina Desaminasa/genética , Citidina Desaminasa/metabolismo , ADN , Sistemas CRISPR-Cas , Citosina/metabolismoRESUMEN
Argonaute (Ago) proteins are programmable nucleases found in all domains of life, playing a crucial role in biological processes like DNA/RNA interference and gene regulation. Mesophilic prokaryotic Agos (pAgos) have gained increasing research interest due to their broad range of potential applications, yet their molecular mechanisms remain poorly understood. Here, we present seven cryo-electron microscopy structures of Kurthia massiliensis Ago (KmAgo) in various states. These structures encompass the steps of apo-form, guide binding, target recognition, cleavage, and release, revealing that KmAgo employs a unique DDD catalytic triad, instead of a DEDD tetrad, for DNA target cleavage under 5'P-DNA guide conditions. Notably, the last catalytic residue, D713, is positioned outside the catalytic pocket in the absence of guide. After guide binding, D713 enters the catalytic pocket. In contrast, the corresponding catalytic residue in other Agos has been consistently located in the catalytic pocket. Moreover, we identified several sites exhibiting enhanced catalytic activity through alanine mutagenesis. These sites have the potential to serve as engineering targets for augmenting the catalytic efficiency of KmAgo. This structural analysis of KmAgo advances the understanding of the diversity of molecular mechanisms by Agos, offering insights for developing and optimizing mesophilic pAgos-based programmable DNA and RNA manipulation tools.
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Proteínas Argonautas , Microscopía por Crioelectrón , Modelos Moleculares , Proteínas Argonautas/metabolismo , Proteínas Argonautas/química , Proteínas Argonautas/genética , Dominio Catalítico , ADN/química , ADN/metabolismo , Unión Proteica , Proteínas Bacterianas/química , Proteínas Bacterianas/metabolismo , Proteínas Bacterianas/genéticaRESUMEN
Farnesoid X receptor (FXR), a ligand-activated transcription factor, plays an important role in maintaining water homeostasis by up-regulating aquaporin 2 (AQP2) expression in renal medullary collecting ducts; however, its role in the survival of renal medullary interstitial cells (RMICs) under hypertonic conditions remains unclear. We cultured primary mouse RMICs and found that the FXR was expressed constitutively in RMICs, and that its expression was significantly up-regulated at both mRNA and protein levels by hypertonic stress. Using luciferase and ChIP assays, we found a potential binding site of nuclear factor kappa-B (NF-κB) located in the FXR gene promoter which can be bound and activated by NF-κB. Moreover, hypertonic stress-induced cell death in RMICs was significantly attenuated by FXR activation but worsened by FXR inhibition. Furthermore, FXR increased the expression and nuclear translocation of hypertonicity-induced tonicity-responsive enhance-binding protein (TonEBP), the expressions of its downstream target gene sodium myo-inositol transporter (SMIT), and heat shock protein 70 (HSP70). The present study demonstrates that the NF-κB/FXR/TonEBP pathway protects RMICs against hypertonic stress.
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Médula Renal , FN-kappa B , Transducción de Señal , Animales , FN-kappa B/metabolismo , Ratones , Médula Renal/metabolismo , Médula Renal/citología , Presión Osmótica , Acuaporina 2/metabolismo , Acuaporina 2/genética , Factores de Transcripción/metabolismo , Factores de Transcripción/genética , Masculino , Ratones Endogámicos C57BL , Proteínas HSP70 de Choque Térmico/metabolismo , Proteínas HSP70 de Choque Térmico/genética , Regiones Promotoras Genéticas , Células Cultivadas , Regulación de la Expresión Génica , Simportadores/metabolismo , Simportadores/genética , Receptores Citoplasmáticos y NuclearesRESUMEN
Identifying a universal activity descriptor for metal oxides, akin to the d-band center for transition metals, remains a significant challenge in catalyst design, largely due to the intricate electronic structures of metal oxides. This review highlights a major advancement in formulating the number of excess electrons (NEE) as an activity descriptor for oxygen evolution reaction (OER) on reducible metal oxide surfaces. We elaborate on the quantitative relationship between NEE and the adsorption properties of OER intermediates, and unveil the decisive role of the octet rule on the OER performance of these oxides. This insight provides a robust theoretical basis for designing effective OER catalysts. Moreover, we discuss critical experimental evidence supporting this theory and summarize recent advances in employing NEE as a guiding principle for developing highly efficient OER catalysts experimentally.
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The liver plays a central role in systemic metabolism and drug degradation. However, it is highly susceptible to damage due to various factors, including metabolic imbalances, excessive alcohol consumption, viral infections, and drug influences. These factors often result in conditions such as fatty liver, hepatitis, and acute or chronic liver injury. Failure to address these injuries could promptly lead to the development of liver cirrhosis and potentially hepatocellular carcinoma (HCC). Prostaglandin E2 (PGE2) is a metabolite of arachidonic acid that belongs to the class of polyunsaturated fatty acids (PUFA) and is synthesized via the cyclooxygenase (COX) pathway. By binding to its G protein coupled receptors (i.e., EP1, EP2, EP3 and EP4), PGE2 has a wide range of physiological and pathophysiology effects, including pain, inflammation, fever, cardiovascular homeostasis, etc. Recently, emerging studies showed that PGE2 plays an indispensable role in liver health and disease. This review focus on the research progress of the role of PGE2 synthase and its receptors in liver physiological and pathophysiological processes and discuss the possibility of developing liver protective drugs targeting the COXs/PGESs/PGE2/EPs axis.
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Dinoprostona , Hígado , Transducción de Señal , Humanos , Dinoprostona/metabolismo , Hígado/metabolismo , Animales , Receptores de Prostaglandina E/metabolismoRESUMEN
The self-assembly of the lanthanide metal-organic frameworks presents a formidable challenge but profound significance. Compared with the metal-organic frameworks based on 4f-3d ions, the chemistry of 4f-3p metal-organic frameworks has not been fully explored so far. In this study, two lanthanide-aluminum-based clusters [Ln6Al(IN)10(µ3-OH)5(µ3-O)3(H2O)8]·xH2O (x = 2, Ln = Gd, abbreviated as Gd6Al; x = 2.5, Ln = Eu, abbreviated as Eu6Al; HIN = isonicotinic acid) have been meticulously designed and obtained by hydrothermal reaction at low pH. The crystallographic study revealed that both Gd6Al and Eu6Al clusters exhibit an unprecedented sandwiched metal-organic framework holding a highly ordered honeycomb network. To our knowledge, it is the first case of Ln-Al-based cluster-organic frameworks. Furthermore, magnetic investigation of Gd6Al manifests a decent magnetic entropy change of -ΔSmmax = 28.8 J kg-1 K-1 at 2 K for ΔH = 7.0 T. Significantly, the introduction of AlIII ions into the lanthanide metal-organic frameworks displays excellent solid-state luminescent capability with a lifetime of 371.6 µs and quantum yield of 6.64%. The construction and investigation of these two Ln-Al clusters represent great progress in the 4f-3p metal-organic framework.
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The discovery of novel electrode materials based on two-dimensional (2D) structures is critical for alkali metal-ion batteries. Herein, we performed first-principles computations to investigate functionalized MXenes, Mo2BT2(T = O, S), which are also regarded as B-based MXenes, or named as MBenes, as potential anode materials for Li-ion batteries and beyond. The pristine and T-terminated Mo2BT2(T = O, S) monolayers reveal metallic character with higher electronic conductivity and are thermodynamically stable with an intrinsic dipole moment. Both Mo2BO2and Mo2BS2monolayers exhibit high theoretical Li/Na/K storage capacity and low ion diffusion barriers. These findings suggest that functionalized Mo2BT2(T = O, S) monolayers are promising for designing viable anode materials for high-performance alkali-ion batteries.
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Fecal microbiota transplantation (FMT) has been shown to improve gut dysbiosis in dogs; however, it has not completely been understood in police dogs. This study aimed to investigate the effects of FMT on performance and gut microflora in Kunming police dogs. Twenty Wolf Cyan dogs were randomly assigned to receive physiological saline or fecal suspension at low, medium, or high doses through oral gavage for 14 days. Growth performance, police performance, serum biochemical profiling, and gut microflora were determined 2-week post-FMT. Dogs after FMT treatment were also subjected to an hour road transportation and then were evaluated for serum stress indicators. Overall, FMT enhanced the growth performance and alleviated diarrhea rate in Kunming dogs with the greatest effects occurring in the low dose FMT (KML) group. The improvement of FMT on police performance was also determined. These above alterations were accompanied by changed serum biochemical parameters as indicated by elevated total protein and albumin and reduced total cholesterol and glycerol. Furthermore, the serum stress indicators after road transportation in dog post-FMT significantly decreased. Increased bacterial diversity and modified bacterial composition were found in the feces of dogs receiving FMT. The fecal samples from FMT dogs were characterized by higher abundances of the genera Lactobacillus, Prevotella, and Fusobacterium and lower concentrations of Cetobacterium, Allobaculum, Bifidobacterium, and Streptococcus. The present study supports a potential benefit of FMT on police performance in Kunming dogs. KEY POINTS: ⢠FMT improves the growth performance and reduces diarrhea rates in Kunming police dogs. ⢠FMT alleviates the serum stress profiles after road transportation in Kunming police dogs. ⢠FMT modifies the gut microbiota composition of Kunming police dogs.
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Trasplante de Microbiota Fecal , Perros de Trabajo , Perros , Animales , Heces , Bifidobacterium , DiarreaRESUMEN
Manure replacing synthetic fertilizer is a viable practice to ensure crop yield and increase soil organic carbon (SOC), but its impact on greenhouse gas (GHG) emissions is inconsistent, thus remains its effect on CF unclear. In this study, a 7-year field experiment was conducted to assess the impact of replacing synthetic fertilizer with manure on crop productivity, SOC sequestration, GHG emissions and crop CF under winter wheat-summer maize cropping system. Five treatments were involved: synthetic nitrogen, phosphorus, and potassium fertilizer (NPK) and 25%, 50%, 75%, and 100% of manure replacing synthetic N (25%M, 50%M, 75%M, and 100%M). Compared with NPK treatment, 25%M and 50%M treatments maintained annual yield (winter wheat plus summer maize) and sustainable yield index (SYI), but 75%M and 100%M treatments significantly decreased annual yield, and 100%M treatment also significantly reduced annual SYI. The SOC content exhibited a significant increasing trend over years in all treatments. After 7 years, SOC storage in manure treatments increased by 3.06-11.82 Mg ha-1 relative to NPK treatment. Manure treatments reduced annual GHG emissions by 14%-60% over NPK treatment. The CF of the cropping system ranged from 0.16 to 0.39 kg CO2 eq kg-1 of grain without considering SOC sequestration, in which the CF of manure treatments lowered by 18%-58% relative to NPK treatment. When SOC sequestration was involved in, the CF varied from -0.39 to 0.37 kg CO2 eq kg-1 of grain, manure treatments significantly reduced the CF by 22%-208% over NPK treatment. It was concluded that replacing 50% of synthetic fertilizer with manure was a sound option for achieving high crop yield and SYI but low CF under the tested cropping system.
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Huella de Carbono , Fertilizantes , Estiércol , Suelo , Triticum , Zea mays , Zea mays/crecimiento & desarrollo , Triticum/crecimiento & desarrollo , Suelo/química , Carbono , Estaciones del Año , Nitrógeno , Productos Agrícolas/crecimiento & desarrollo , Agricultura/métodos , Gases de Efecto InvernaderoRESUMEN
Liver function indicators are often impaired in patients with type 2 diabetes mellitus (T2DM), who present higher concentrations of aspartate aminotransferase, alanine aminotransferase, and gamma-glutamyl transferase than individuals without diabetes. However, the mechanism of liver injury in patients with T2DM has not been clearly elucidated. In this study, we performed a lipidomics analysis on the liver of T2DM mice, and we found that phosphatidylethanolamine (PE) levels were low in T2DM, along with an increase in diglyceride, which may be due to a decrease in the levels of phosphoethanolamine cytidylyltransferase (Pcyt2), thus likely affecting the de novo synthesis of PE. The phosphatidylserine decarboxylase pathway did not change significantly in the T2DM model, although both pathways are critical sources of PE. Supplementation with CDP-ethanolamine (CDP-etn) to increase the production of PE from the CDP-etn pathway reversed high glucose and FFA (HG&FFA)-induced mitochondrial damage including increased apoptosis, decreased ATP synthesis, decreased mitochondrial membrane potential, and increased reactive oxygen species, whereas supplementation with lysophosphatidylethanolamine, which can increase PE production in the phosphatidylserine decarboxylase pathway, did not. Additionally, we found that overexpression of PCYT2 significantly ameliorated ATP synthesis and abnormal mitochondrial morphology induced by HG&FFA. Finally, the BAX/Bcl-2/caspase3 apoptosis pathway was activated in hepatocytes of the T2DM model, which could also be reversed by CDP-etn supplements and PCYT2 overexpression. In summary, in the liver of T2DM mice, Pcyt2 reduction may lead to a decrease in the levels of PE, whereas CDP-etn supplementation and PCYT2 overexpression ameliorate partial mitochondrial function and apoptosis in HG&FFA-stimulated L02 cells.
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Diabetes Mellitus Tipo 2 , Fosfatidiletanolaminas , Ratones , Animales , Fosfatidiletanolaminas/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , ARN Nucleotidiltransferasas/metabolismo , Etanolaminas/farmacología , Etanolaminas/metabolismo , Hepatocitos/metabolismo , Mitocondrias/metabolismo , Apoptosis , Adenosina Trifosfato/metabolismoRESUMEN
The octet rule is a fundamental theory in the chemical bonding of main-group elements, which achieve stable configurations by gaining, losing, or sharing electrons. However, the conventional octet rule, as depicted through Lewis structures, is inadequate for describing the electron delocalization in boron allotropes and boron-rich compounds due to the electron deficiency of boron. To address this, we introduce the concept of fractional electron occupancies, which more accurately reflect the electron delocalization in boron systems. Based on this, we propose a generalized octet rule that provides a more comprehensive understanding of the complex bonding configurations in boron allotropes and boron-rich compounds. Importantly, our predictions for α-B12 are validated by both first-principles calculations and existing experimental data. Beyond boron, this generalized octet rule is also applicable to systems with multiple resonance structures.
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Multiple genome-wide association studies (GWASs) have reproducibly identified the MTMR3/HORMAD2/LIF/OSM locus to be associated with IgA nephropathy (IgAN). However, the causal variant(s), implicated gene(s), and altered mechanisms remain poorly understood. Here, we performed fine-mapping analyses based on GWAS datasets encompassing 2762 IgAN cases and 5803 control individuals, and identified rs4823074 as the candidate causal variant that intersects the MTMR3 promoter in B-lymphoblastoid cells. Mendelian randomization studies suggested the risk allele may modulate disease susceptibility by affecting serum IgA levels through increased MTMR3 expression. Consistently, elevated MTMR3 expression in peripheral blood mononuclear cells was observed in patients with IgAN. Further mechanistic studies in vitro demonstrated that MTMR3 increased IgA production dependent upon its phosphatidylinositol 3-phosphate binding domain. Moreover, our study provided the in vivo functional evidence that Mtmr3-/- mice exhibited defective Toll Like Receptor 9-induced IgA production, glomerular IgA deposition, as well as mesangial cell proliferation. RNA-seq and pathway analyses showed that MTMR3 deficiency resulted in an impaired intestinal immune network for IgA production. Thus, our results support the role of MTMR3 in IgAN pathogenesis by enhancing Toll Like Receptor 9-induced IgA immunity.
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Glomerulonefritis por IGA , Animales , Ratones , Alelos , Estudio de Asociación del Genoma Completo , Glomerulonefritis por IGA/patología , Inmunoglobulina A , Leucocitos Mononucleares/metabolismo , Receptor Toll-Like 9 , HumanosRESUMEN
Through inducing death receptor (DR) clustering to activate downstream signaling, tumor necrosis factor related apoptosis inducing ligand (TRAIL) trimers trigger apoptosis of tumor cells. However, the poor agonistic activity of current TRAIL-based therapeutics limits their antitumor efficiency. The nanoscale spatial organization of TRAIL trimers at different interligand distances is still challenging, which is essential for the understanding of interaction pattern between TRAIL and DR. In this study, a flat rectangular DNA origami is employed as display scaffold, and an "engraving-printing" strategy is developed to rapidly decorate three TRAIL monomers onto its surface to form DNA-TRAIL3 trimer (DNA origami with surface decoration of three TRAIL monomers). With the spatial addressability of DNA origami, the interligand distances are precisely controlled from 15 to 60 nm. Through comparing the receptor affinity, agonistic activity and cytotoxicity of these DNA-TRAIL3 trimers, it is found that ≈40 nm is the critical interligand distance of DNA-TRAIL3 trimers to induce death receptor clustering and the resulting apoptosis.Finally, a hypothetical "active unit" model is proposed for the DR5 clustering induced by DNA-TRAIL3 trimers.
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Neoplasias , Receptores del Ligando Inductor de Apoptosis Relacionado con TNF , Ligandos , Receptores del Ligando Inductor de Apoptosis Relacionado con TNF/genética , Receptores del Ligando Inductor de Apoptosis Relacionado con TNF/metabolismo , Ligando Inductor de Apoptosis Relacionado con TNF/genética , Ligando Inductor de Apoptosis Relacionado con TNF/metabolismo , Ligando Inductor de Apoptosis Relacionado con TNF/farmacología , Apoptosis , Factor de Necrosis Tumoral alfa , Línea Celular TumoralRESUMEN
Photocatalytic decomposition of water to produce hydrogen H2 is an ideal way to solve energy and environmental problems, and the development of highly efficient polyoxometalate catalysts for photocatalytic hydrogen production has attracted wide attention. Herein, two Cu-modified Strandberg-type organophosphomolybdates were successfully synthesized, [Cu(C8H7N3)(H2O)2]2[(C6H5PO3)2Mo5O15]·4H2O (1) and [Cu(phen)(H2O)][Cu(phen)(H2O)2][(C6H5PO3)2Mo5O15]·2H2O (2) ([(C6H5P)2Mo5O21]Cu2) (C8H7N3 = 2-(1H-pyrazol-3-yl)pyridine, phen = 1,10-phenanthroline). Two Strandberg-type organophosphomolybdates can be used for visible-light-driven hydrogen production. Also, compound 2 exhibits an H2 production rate of 6399 µmol g-1 h-1 after 8 h light exposure in the presence of photosensitization agent [Ir(dtbbpy)(ppy)2][PF6] and TEOA. In addition, cyclic tests showed that compound 2 could be recycled four times without a significant reduction in catalytic performance. This work offers fresh insight into the development of novel polyoxometalates for efficient hydrogen evolution.
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Osteoarthritis (OA) mainly occurs in the elderly population and seriously affects their quality of life (QOL). Strontium (Sr) ions have shown positive effects on bone tissue and are promising for OA treatment. However, the adequate treatment dosage and underlying mechanisms are unclear. This study investigated the effects and underlying mechanisms of different concentrations of Sr ions in a mouse model of OA induced by destabilization of the medial meniscus (DMM) surgery. DMM-induced OA mice received intra-articular injections of different concentrations of Sr ions, and a suitable concentration of Sr ions was found to improve OA. Furthermore, we investigated the mechanism by which Sr ions mediate senescence and autophagy in fibroblast-like synoviocytes (FLSs) in the synovial tissues of DMM-induced OA mice. OA mice treated with 10 µl of 5 mmol/L SrCl2 showed the greatest improvement in pain-related behavior and cartilage damage. In addition, in vivo and in vitro experiments revealed that Sr ions inhibit senescence and improve the autophagic function of FLSs. We also found that enhancement of the autophagic function of FLSs could effectively slow down senescence. Therefore, we show that Sr ions through the AMPK/mTOR/LC3B-II signal axis improve FLSs autophagy function and delay FLSs senescence, and furthermore, improve OA. These results suggest that senescence and autophagy function of FLSs may serve as promising targets for OA treatment, and that Sr ions may inhibit OA progression through these two targets.
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Osteoartritis , Sinoviocitos , Anciano , Humanos , Ratones , Animales , Calidad de Vida , Osteoartritis/tratamiento farmacológico , Autofagia , FibroblastosRESUMEN
Developing transition metal dichalcogenides as electrocatalysts has attracted great interest due to their tunable electronic properties and good thermal stabilities. Herein, we propose a PdTe2 bilayer as a promising electrocatalyst candidate towards the oxygen reduction reaction (ORR), based on extensive investigation of the electronic properties of PdTe2 thin films as well as atomic-level reaction kinetics at explicit electrode potentials. We verify that under electrochemical reducing conditions, the electron emerging on the electrode surface is directly transferred to O2 adsorbed on the PdTe2 bilayer, which greatly reduces the dissociation barrier of O2, and thereby facilitates the ORR to proceed via a dissociative pathway. Moreover, the barriers of the electrochemical steps in this pathway are all found to be less than 0.1 eV at the ORR limiting potential, demonstrating fast ORR kinetics at ambient conditions. This unique mechanism offers excellent energy efficiency and four-electron selectivity for the PdTe2 bilayer, and it is identified as a promising candidate for fuel cell applications.
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Renal fibrosis is a common pathological feature of chronic kidney disease (CKD) with various etiologies, which seriously affects the structure and function of the kidney. Pregnane X receptor (PXR) is a member of the nuclear receptor superfamily and plays a critical role in regulating the genes related to xenobiotic and endobiotic metabolism in mammals. Previous studies show that PXR is expressed in the kidney and has protective effect against acute kidney injury (AKI). In this study, we investigated the role of PXR in CKD. Adenine diet-induced CKD (AD) model was established in wild-type and PXR humanized (hPXR) mice, respectively, which were treated with pregnenolone-16α-carbonitrile (PCN, 50 mg/kg, twice a week for 4 weeks) or rifampicin (RIF, 10 mg·kg-1·d-1, for 4 weeks). We showed that both PCN and RIF, which activated mouse and human PXR, respectively, improved renal function and attenuated renal fibrosis in the two types of AD mice. In addition, PCN treatment also alleviated renal fibrosis in unilateral ureter obstruction (UUO) mice. On the contrary, PXR gene deficiency exacerbated renal dysfunction and fibrosis in both adenine- and UUO-induced CKD mice. We found that PCN treatment suppressed the expression of the profibrotic Wnt7a and ß-catenin in AD mice and in cultured mouse renal tubular epithelial cells treated with TGFß1 in vitro. We demonstrated that PXR was colocalized and interacted with p53 in the nuclei of tubular epithelial cells. Overexpression of p53 increased the expression of Wnt7a, ß-catenin and its downstream gene fibronectin. We further revealed that p53 bound to the promoter of Wnt7a gene to increase its transcription and ß-catenin activation, leading to increased expression of the downstream profibrotic genes, which was inhibited by PXR. Taken together, PXR activation alleviates renal fibrosis in mice via interacting with p53 and inhibiting the Wnt7a/ß-catenin signaling pathway.
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Receptor X de Pregnano , Insuficiencia Renal Crónica , Vía de Señalización Wnt , Animales , Humanos , Ratones , beta Catenina/metabolismo , Fibrosis , Mamíferos/metabolismo , Receptor X de Pregnano/metabolismo , Receptores de Esteroides/genética , Receptores de Esteroides/metabolismo , Insuficiencia Renal Crónica/inducido químicamente , Insuficiencia Renal Crónica/tratamiento farmacológico , Transducción de Señal , Proteína p53 Supresora de Tumor/metabolismo , Rifampin/farmacologíaRESUMEN
The efficient catalytic activity and strong durability possibility of carbon-based three-dimensional fiber materials remains an important challenge in Electro-Fenton advanced oxidation technology. Graphite felt (GF) is a promising electrode material for 2-electron oxygen reduction reaction but with higher catalytic inertia. Anodizing modification of GF has been proved to enhance it electro-catalytic property, but the disadvantages of excessive or insufficient oxidation of GF need further improved. Herein, the surface reconstituted graphite felt by anodizing and HNO3 ultrasonic integrated treatment was used as cathode to degrade norfloxacin (NOR) and the substantial role of different modification processes was essentially investigated. Compared with the single modification process, the synergistic interaction between these two methods can generate more defective active sites (DASs) on GF surface and greatly improved 2-electron ORR activity. The H2O2 can be further co-activated by Fe2+ and DASs into â¢OH(ads and free) and â¢O2- to efficiently degrade NOR. The treated GF with 20 min anodizing and 1 h HNO3 ultrasound had the highest electrocatalytic activity in a wide electric potential (-0.4 V to -0.8 V) and pH range (3-9) in system and the efficient removal rate of NOR was basically maintained after 5 cycles. Under optimal reaction conditions, 50 mg L-1 NOR achieved 93% degradation and almost 63% of NOR was completely mineralized within 120 min. The possible NOR degradation pathways and ecotoxicity of intermediates were analyzed by LC-MS and T.E.S.T. theoretical calculation. This paper provided the underlying insights into designing a high-efficiency carbon-based cathode materials for commercial antibiotic wastewater treatment.
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Grafito , Contaminantes Químicos del Agua , Grafito/química , Norfloxacino , Peróxido de Hidrógeno/química , Hierro/química , Dominio Catalítico , Carbono , Oxidación-Reducción , Electrodos , Antibacterianos , Contaminantes Químicos del Agua/químicaRESUMEN
BACKGROUND: The similar visual appearance of superficial basal cell carcinoma (sBCC) and Bowen's disease (BD) may cause confusion for diagnosis. OBJECTIVE: The aim of the study was to investigate the value of ultra-high-frequency ultrasound (uHFUS) in differentiating sBCC from BD. MATERIALS AND METHODS: This prospective study included a pilot cohort of 110 patients (73 BDs and 37 sBCCs) from November 2016 to October 2020 and a validation cohort of 42 patients (30 BDs and 12 sBCCs) from July 2021 to December 2021. Clinical and uHFUS features of pathologically confirmed sBCC and BD were assessed. A predictive model was developed based on the uHFUS features of the pilot cohort. Subsequently, the model was validated and compared with clinical diagnosis in the validation cohort. RESULTS: uHFUS features with significant differences between sBCC and BD included lesion surface, skin layer involvement, hyperkeratosis, and hyperechoic spots (all p < 0.05). A prediction model based on the above features was established to identify sBCC and BD in the pilot and validation cohorts with areas under the curve (AUC) of 0.908 and 0.923, sensitivity of 82.3% and 83.3%, specificity of 91.9% and 91.7%, and accuracy of 85.5% and 85.7%, respectively, which were significantly higher than those obtained by clinical diagnosis based on photographic pictures of lesions, with the AUC of 0.692, sensitivity of 63.3%, specificity of 75.3%, and accuracy of 66.7% (all p < 0.05). CONCLUSION: uHFUS provides detailed internal features of sBCC and BD, which facilitates the differentiation between sBCC and BD, and its diagnostic performance is superior to clinical diagnosis.