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1.
Int J Biol Sci ; 20(7): 2507-2531, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38725846

RESUMO

Neuropeptide substance P (SP) belongs to a family of bioactive peptides and regulates many human diseases. This study aims to investigate the role and underlying mechanisms of SP in colitis. Here, activated SP-positive neurons and increased SP expression were observed in dextran sodium sulfate (DSS)-induced colitis lesions in mice. Administration of exogenous SP efficiently ameliorated the clinical symptoms, impaired intestinal barrier function, and inflammatory response. Mechanistically, SP protected mitochondria from damage caused by DSS or TNF-α exposure, preventing mitochondrial DNA (mtDNA) leakage into the cytoplasm, thereby inhibiting the cyclic GMP-AMP synthase-stimulator of interferon genes (cGAS-STING) pathway. SP can also directly prevent STING phosphorylation through the neurokinin-1 receptor (NK1R), thereby inhibiting the activation of the TBK1-IRF3 signaling pathway. Further studies revealed that SP alleviated the DSS or TNF-α-induced ferroptosis process, which was associated with repressing the cGAS-STING signaling pathway. Notably, we identified that the NK1R inhibition reversed the effects of SP on inflammation and ferroptosis via the cGAS-STING pathway. Collectively, we unveil that SP attenuates inflammation and ferroptosis via suppressing the mtDNA-cGAS-STING or directly acting on the STING pathway, contributing to improving colitis in an NK1R-dependent manner. These findings provide a novel mechanism of SP regulating ulcerative colitis (UC) disease.


Assuntos
Colite , Sulfato de Dextrana , Ferroptose , Inflamação , Proteínas de Membrana , Camundongos Endogâmicos C57BL , Nucleotidiltransferases , Transdução de Sinais , Substância P , Animais , Nucleotidiltransferases/metabolismo , Transdução de Sinais/efeitos dos fármacos , Camundongos , Colite/metabolismo , Colite/induzido quimicamente , Substância P/metabolismo , Proteínas de Membrana/metabolismo , Ferroptose/efeitos dos fármacos , Inflamação/metabolismo , Sulfato de Dextrana/toxicidade , Masculino , Receptores da Neurocinina-1/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , DNA Mitocondrial/metabolismo
2.
Phys Chem Chem Phys ; 26(17): 13182-13197, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38630138

RESUMO

The gasification of carbon with O2, CO2, and H2O oxidants plays an important role in several energy-based applications. As most of the industrial gasification processes are conducted under mixed-atmosphere conditions, the oxidation of carbon in binary oxidant mixtures becomes crucially important. Using reactive force-field (ReaxFF) potentials, extensive MD simulations were carried out on the oxidation behavior of graphene in mixed O2/H2O and O2/CO2 environments for a range of gas compositions and temperatures. A graphene sheet with a line defect comprising of eight and four-membered rings was used as the starting carbon structure. In addition to enhanced carbon gasification with oxygen additions, MD simulations showed synergistic interactions between different oxidants and their net influence on the overall reactivities. The gasification levels achieved under the binary system were higher than the linear combination of contributions from individual oxidants. The addition of ∼40% O2 in the binary mix was identified as the region with the highest reactivity during the initial stages of gasification. The oxidation reactions with oxygen were found to start instantaneously in the presence of H2O or CO2 instead of the usual initial delay. A very fast reaction kinetics was also observed in the initial stages in the presence of oxygen. Our results show that the gasification reactions under H2O and CO2 started at lower temperatures than O2 thereby creating a partially oxidized structure. Due to the presence of a large number of activation sites, very high rates of gasification were achieved with oxygen. These findings could help identify optimal oxidant compositions towards maximizing carbon gasification and minimizing CO2 emissions.

3.
Vascular ; : 17085381241240686, 2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38513670

RESUMO

OBJECTIVE: Low-frequency oscillations (LFOs) observed in the periphery may reflect physiological processes. The aim of this study was to investigate these processes' effects on LFOs and the differences between healthy subjects and those with peripheral arteriosclerosis disease (PAD). METHODS: 14 PAD patients and 25 healthy controls were studied in resting (RS) and passive leg raising (PLR) states. We simultaneously measured LFOs at the peripheral left earlobes (LE), right earlobes (RE), left fingertips (LF), right fingertips (RF), left toes (LT), and right toes (RT), along with coherence and phase shift analysis processing. RESULTS: The coherence coefficients in the PAD group were lower than those in the healthy group (p < .01), and the phase shifts in the PAD group were higher than those in the healthy group (p < .01) in a resting state. Mild to moderate PAD patients had greater coherence coefficients and smaller phase shifts than severe PAD patients. 0.05 Hz PLR LFOs originating in the LT can be observed in other peripheral positions. The proportion of occurrence times for 0.05 Hz PLR LFOs peaks observed at different peripheral positions was different in healthy subjects, patients with bilateral multiple lower limb arteriosclerosis, and those with left or right lower limb arteriosclerosis. CONCLUSION: The coherence coefficient and phase shift characteristics of LFOs were different between healthy subjects and PAD patients. LFOs have the potential to provide valuable physiological process information associated with atherosclerosis in the periphery.

4.
Antioxidants (Basel) ; 13(2)2024 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-38397792

RESUMO

Ischemic stroke is a devastating disease leading to neurologic impairment. Compounding the issue is the very limited array of available interventions. The activation of a γ-aminobutyric acid (GABA) type A receptor (GABAAR) has been reported to produce neuroprotective properties during cerebral ischemia, but its mechanism of action is not yet fully understood. Here, in a rat model of photochemically induced cerebral ischemia, we found that muscimol, a GABAAR agonist, modulated GABAergic signaling, ameliorated anxiety-like behaviors, and attenuated neuronal damage in rats suffering cerebral ischemia. Moreover, GABAAR activation improved brain antioxidant levels, reducing the accumulation of oxidative products, which was closely associated with the NO/NOS pathway. Notably, the inhibition of autophagy markedly relieved the neuronal insult caused by cerebral ischemia. We further established an oxygen-glucose deprivation (OGD)-induced PC12 cell injury model. Both in vivo and in vitro experiments demonstrated that GABAAR activation obviously suppressed autophagy by regulating the AMPK-mTOR pathway. Additionally, GABAAR activation inhibited apoptosis through inhibiting the Bax/Bcl-2 pathway. These data suggest that GABAAR activation exerts neuroprotective effects during cerebral ischemia through improving oxidative stress and inhibiting autophagy and apoptosis. Our findings indicate that GABAAR serves as a target for treating cerebral ischemia and highlight the GABAAR-mediated autophagy signaling pathway.

5.
BMC Med Genomics ; 17(1): 38, 2024 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-38287380

RESUMO

BACKGROUND: Single nucleotide polymorphisms (SNPs) in the nucleotide-binding domain leucine-rich repeat protein-3 (NLRP3) gene are reported to be linked to many inflammatory disorders. However, uncertainty persists over the associations between these SNPs and susceptibilities to chronic osteomyelitis (COM). This study aimed to investigate potential relationships between NLRP3 gene SNPs and the risks of developing COM in a Chinese Han cohort. METHODS: The four tag SNPs of the NLRP3 gene were genotyped in a total of 428 COM patients and 368 healthy controlsusing the SNapShot technique. The genotype distribution, mutant allele frequency, and the four genetic models (dominant, recessive, homozygous, and heterozygous) of the four SNPs were compared between the two groups. RESULTS: A significant association was found between rs10754558 polymorphism and the probability of COM occurence by the heterozygous model (P = 0.037, odds ratio [OR] = 1.541, 95% confidence interval [CI] = 1.025-2.319), indicating that rs10754558 may be associated with a higher risk of developing COM.In addition, possible relationship was found between rs7525979 polymorphism and the risk of COM development by the outcomes of homozygous (P = 0.073, OR = 0.453, 95% CI = 0.187-1.097) and recessive (P = 0.093, OR = 0.478, 95% CI = 0.198-1.151) models, though no statistical differences were obtained. CONCLUSIONS: Outcomes of the present study showed, for the first time, that rs10754558 polymorphism of the NLRP3 gene may increase the risk of COM development in this Chinese Han population, with genotype CG as a risk factor. Nonetheless, this conclusion requires verification from further studies with a larger sample size.


Assuntos
Proteína 3 que Contém Domínio de Pirina da Família NLR , Osteomielite , Humanos , Estudos de Casos e Controles , China , Frequência do Gene , Predisposição Genética para Doença , Genótipo , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Osteomielite/genética , Polimorfismo de Nucleotídeo Único
6.
Small ; 20(20): e2308908, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38105418

RESUMO

The environmental deterioration caused by dye wastewater discharge has received considerable attention in recent decades. One of the most promising approaches to addressing the aforementioned environmental issue is the development of photocatalysts with high solar energy consumption efficiency for the treatment of dye-contaminated water. In this study, a novel low-cost π-π biomass-derived black carbon modified g-C3N4 coupled FeIn2S4 composite (i.e., FeInS/BC-CN) photocatalyst is successfully designed and fabricated that reveals significantly improved photocatalytic performance for the degradation of Eosin Yellow (EY) dye in aqueous solution. Under dark and subsequent visible light irradiation, the amount optimized composite reveals 99% removal performance for EY dye, almost three-fold compared to that of the pristine FeInS and BC-CN counterparts. Further, it is confirmed by means of the electron spin resonance spectrometry, quenching experiments, and density functional theory (DFT) calculations, that the hydroxyl radicals (•OH) and superoxide radicals (•O2 -) are the dominant oxidation species involved in the degradation process of EY dye. In addition, a systematic photocatalytic degradation route is proposed based on the resultant degradation intermediates detectedduring liquid chromatography tandem mass spectrometry (LC-MS/MS) analysis. This work provides an innovative idea for the development of advanced photocatalysts to mitigate water pollution.

7.
Small ; : e2307260, 2023 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-38054761

RESUMO

All-solid lithium (Li) metal batteries (ASSLBs) with sulfide-based solid electrolyte (SEs) films exhibit excellent electrochemical performance, rendering them capable of satisfying the growing demand for energy storage systems. However, challenges persist in the application of SEs film owing to their reactivity with Li metal and uncontrolled formation of lithium dendrites. In this study, iodine-doped poly(vinylidenefluoride-hexafluoropropylene) (PVDF-HFP) as an interlayer (PHI) to establish a stable interphase between Li metal and Li6 PS5 Cl (LPSCl) films is investigated. The release of I ions and PVDF-HFP produces LiI and LiF, effectively suppressing lithium dendrite growth. Density functional theory calculations show that the synthesized interlayer layer exhibits high interfacial energy. Results show that the PHI@Li/LPSCl film/PHI@Li symmetrical cells can cycle for more than 650 h at 0.1 mA cm-2 . The PHI@Li/LPSCl film/NCM622 cell exhibits a distinct enhancement in capacity retention of ≈26% when using LiNi0.6 Mn0.2 Co0.2 O2 (NCM622) as the cathode, compared to pristine Li metal as the anode. This study presents a feasible method for producing next-generation dendrite-free SEs films, promoting their practical use in ASSLBs.

8.
ACS Appl Mater Interfaces ; 15(51): 59444-59453, 2023 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-38091379

RESUMO

The photocatalytic oxygen evolution of bismuth oxybromide (BiOBr) is greatly hindered by its low visible-light response and high electron-hole recombination. Nonmetal doping can effectively alleviate these issues, leading to improvement in photocatalytic performance. Herein, Bi2Te3 was introduced as both the Te doping source and the morphology-control template to improve the photocatalytic performance of BiOBr. Appropriate amounts of Te are critical to maintain the ultrathin plate-like structure of BiOBr, whereas excessive Te results in the formation of a flower-like architecture. Oxygen evolution activity disclosed that a plate-like structure is essential for realizing higher performance owing to sufficient light utilization and efficient charge separation. An optimal oxygen evolution rate of 368.0 µmol h-1 g-1 was achieved for the Te-doped sample, which is 2.3-fold as that of the undoped BiOBr (158.9 µmol h-1 g-1). Theoretical calculations demonstrated that Te doping can induce impurity levels above the valence band of BiOBr, which slightly narrowed the band gap and strengthened the light absorption in the range of 400-800 nm. More importantly, Te dopants could act as shallow traps for confining the excited electrons, thus prolonging the carrier lifetime. This work provides a novel strategy to prepare highly efficient photocatalysts by simultaneously realizing morphology manipulation and nonmetal doping.

9.
RNA Biol ; 20(1): 875-892, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-37966982

RESUMO

RNA methyltransferase DNMT2/TRDMT1 is the most conserved member of the DNMT family from bacteria to plants and mammals. In previous studies, we found some determinants for tRNA recognition of DNMT2/TRDMT1, but the preference mechanism of this enzyme for substrates tRNA and DNA remains to be explored. In the present study, CFT-containing target recognition domain (TRD) and target recognition extension domain (TRED) in DNMT2/TRDMT1 play a crucial role in the substrate DNA and RNA selection during the evolution. Moreover, the classical substrate tRNA for DNMT2/TRDMT1 had a characteristic sequence CUXXCAC in the anticodon loop. Position 35 was occupied by U, making cytosine-38 (C38) twist into the loop, whereas C, G or A was located at position 35, keeping the C38-flipping state. Hence, the substrate preference could be modulated by the easily flipped state of target cytosine in tRNA, as well as TRD and TRED. Additionally, DNMT2/TRDMT1 cancer mutant activity was collectively mediated by five enzymatic characteristics, which might impact gene expressions. Importantly, G155C, G155V and G155S mutations reduced enzymatic activities and showed significant associations with diseases using seven prediction methods. Altogether, these findings will assist in illustrating the substrate preference mechanism of DNMT2/TRDMT1 and provide a promising therapeutic strategy for cancer.


Assuntos
DNA (Citosina-5-)-Metiltransferases , Neoplasias , Animais , Humanos , DNA (Citosina-5-)-Metiltransferases/metabolismo , Metiltransferases , DNA , RNA de Transferência/genética , Citosina/metabolismo , Mamíferos/genética
10.
Cytotechnology ; 75(6): 505-516, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37841957

RESUMO

Osteoporosis is a complicated multifactorial disorder characterized by low bone mass and deteriorated bone microarchitecture with an elevated fracture risk. MicroRNAs play important roles in osteoblastic differentiation. In the present study, we found that miR-224-5p was markedly downregulated during the osteogenic differentiation of C2C12 cells. Overexpression of miR-224-5p in C2C12 cells inhibited osteoblast activity, as indicated by reduced ALP activity, matrix mineralization and the expression of osteogenic marker genes. Moreover, we demonstrated that Runx2 and Sp7 were direct targets of miR-224-5p. Furthermore, the specific inhibition of miR-224-5p by femoral bone marrow cavity injection with miR-224-5p antagomir prevented ovariectomy-induced bone loss. Finally, we found that the levels of miR-224-5p were markedly elevated in the sera of patients with osteoporosis. Collectively, this study revealed that miR-224-5p negatively regulates osteogenic differentiation by targeting Runx2 and Sp7. It also highlights the potential use of miR-224-5p as a therapeutic target and diagnostic biomarker for osteoporosis. Supplementary information: The online version contains supplementary material available at 10.1007/s10616-023-00593-z.

11.
Curr Drug Deliv ; 2023 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-37818569

RESUMO

Immunomodulatory mechanisms are indispensable and key factors in maintaining the balance of the environment in humans. When the immune function of the immune system is impaired, autoimmune diseases occur. Excessive body fatigue, natural aging of the human body, malnutrition, genetic factors and other reasons cause low immune function, due to which the body is prone to being infected by bacteria or cancer. Clinically, the existing therapeutic drugs still have problems such as high toxicity, long treatment cycle, drug resistance and high price, so we still need to explore and develop a high efficiency and low toxicity drug. Poly(lactic-co-glycolic acid) (PLGA) refers to a non-toxic polymer compound that exhibits excellent biocompatibility. Traditional Chinese medicine (TCM) monomers come from natural plants, and have the characteristics of high efficiency and low toxicity. Applying PLGA to TCM monomers can make up for the defects of traditional dosage forms, improve bioavailability, reduce the frequency and dosage of drug use, and reduce toxicity and side effects, thus having the characteristics of sustained release and targeting. Accordingly, PLGA nanoparticles loaded with TCM monomers have been the focus of development. The previous research on drug loading advantages, preparation methods, and immune regulation of TCM PLGA nanoparticles is summarized in the following sections.

12.
iScience ; 26(10): 107838, 2023 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-37752950

RESUMO

HS3ST3B1-IT1 was identified as a downregulated long noncoding RNA in osteoarthritic cartilage. However, its roles and mechanisms in the pathogenesis of osteoarthritis (OA) are unclear. In this study, we demonstrated that the expressions of HS3ST3B1-IT1 and its maternal gene HS3ST3B1 were downregulated and positively correlated in osteoarthritic cartilage. Overexpression of HS3ST3B1-IT1 significantly increased chondrocyte viability, inhibited chondrocyte apoptosis, and upregulated extracellular matrix (ECM) proteins, whereas HS3ST3B1-IT1 knockdown had the opposite effects. In addition, HS3ST3B1-IT1 significantly ameliorated monosodium-iodoacetate-induced OA in vivo. Mechanistically, HS3ST3B1-IT1 upregulated HS3ST3B1 expression by blocking its ubiquitination-mediated degradation. Knockdown of HS3ST3B1 reversed the effects of HS3ST3B1-IT1 on chondrocyte viability, apoptosis, and ECM metabolism. AlkB homolog 5 (ALKBH5)-mediated N6-methyladenosine (m6A) demethylation stabilized HS3ST3B1-IT1 RNA. Together, our data revealed that ALKBH5-mediated upregulation of HS3ST3B1-IT1 suppressed OA progression by elevating HS3ST3B1 expression, suggesting that HS3ST3B1-IT1/HS3ST3B1 may serve as potential therapeutic targets for OA treatment.

13.
Biomaterials ; 302: 122297, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37666102

RESUMO

The dysfunction of tumor infiltrating lymphocytes (TILs) directly correlates with out of control of tumor growth and metastasis. New approaches and insightful clarity for rescuing TILs dysfunction are urgently needed. Here, we design two heterogenous antigens based on MHC-I epitope and MHC-II epitope from tumor, and assemble heterogenous antigens by electrostatic interactions and π-π stacking into heteroantigen-assembled nanovaccine (HANV). HANV not only significantly increases the abundance of CD8+ and CD4+ TILs, but also elicits stronger polyfunctionality of CD8+ and CD4+ TILs in vivo. Enhanced polyfunctionality of CD8+ and CD4+ TILs positively correlate to suppression of tumor growth and metastasis in melanoma-bearing mouse models. We also validate that nucleotide-binding oligomerization domain-containing protein 2 (NOD2) dominantly enhances anti-tumor capacity of TILs in a temporal immunoregulation manner. This work presents a new insight in developing HANV as a rational strategy to shape TILs polyfunctionality for tumor growth and metastasis.


Assuntos
Linfócitos do Interstício Tumoral , Melanoma , Animais , Camundongos , Linfócitos do Interstício Tumoral/patologia , Melanoma/patologia , Epitopos , Antígenos Heterófilos , Linfócitos T CD8-Positivos
14.
Life Sci ; 329: 121984, 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37527767

RESUMO

AIMS: Emerging research indicates that γ-aminobutyric acid (GABA) provides substantial benefits during enteritis. Nevertheless, GABA signaling roles on enteric glial cells (EGCs) remain unknown. The study's objective was to evaluate the underlying mechanisms of GABA signaling on EGCs in vitro and in vivo. MAIN METHODS: We established LPS-induced mouse models and stimulated EGCs with LPS to mimic intestinal inflammation, and combined GABA, GABAA receptor (GABAAR) or GABAB receptor (GABABR) agonists to explore the exact mechanisms of GABA signaling. KEY FINDINGS: EGCs were immunopositive for GAD65, GAD67, GAT1, GABAARα1, GABAARα3, and GABABR1, indicating GABAergic and GABAceptive properties. GABA receptor activation significantly inhibited the high secretions of proinflammatory factors in EGCs upon LPS stimulation. Interestingly, we found that EGCs express immune-related molecules such as CD16, CD32, CD80, CD86, MHC II, iNOS, Arg1, and CD206, thus establishing their characterization of E1 and E2 phenotype. EGCs exposed to LPS mainly acted as E1 phenotype, whereas GABABR activation strongly promoted EGCs polarization into E2 phenotype. Transcriptome analysis of EGCs indicated that GABA, GABAAR or GABABR agonists treatment participated in various biological processes, however all of these treatments exhibit inhibitory effects on NF-κB pathway. Notably, in LPS-induced mice, activation of GABABR mitigated intestinal damage through modulating inflammatory factors expressions, strengthening sIgA and IgG levels, inhibiting NF-κB pathway and facilitating EGCs to transform into E2 phenotype. SIGNIFICANCE: These data demonstrate that the anti-inflammatory actions of GABA signaling system offer in enteritis via regulating EGCs-polarized function through impeding NF-κB pathway, thus providing potential targets for intestinal inflammatory diseases.


Assuntos
NF-kappa B , Receptores de GABA , Camundongos , Animais , NF-kappa B/metabolismo , Receptores de GABA/metabolismo , Lipopolissacarídeos/farmacologia , Lipopolissacarídeos/metabolismo , Neuroglia/metabolismo , Ácido gama-Aminobutírico/metabolismo , Inflamação/metabolismo
15.
Orthop Surg ; 15(10): 2540-2548, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37526145

RESUMO

BACKGROUND: Minimally invasive reduction and fixation of intra-articular calcaneal fractures poses great challenges for orthopaedic surgeons. The aim of the present study was to report the technical points, evaluate the efficacy of minimally invasive reduction and internal fixation assisted by the temporary limb reconstruction system (LRS) external fixator for intra-articular calcaneal fractures, and propose the indications of our protocol. METHODS: In this retrospective study, a series of 34 consecutive closed and displaced intra-articular calcaneal fractures involving the articular surface were treated by this technology between June 2016 and April 2018. X-ray and computed tomography (CT) scans were performed before and after surgery to measure Bohler's angle; the length, height, and width of the calcaneus; and the mechanical axis of the hindfoot. Postoperative complications were recorded. Imaging and clinical outcomes were comprehensively evaluated using the American Orthopaedic Foot and Ankle Society (AOFAS) hindfoot-ankle scoring system. After testing the normality of the data, Bohler's angle and the length of calcaneus were compared using the Wilcoxon signed-rank test. The height, width of the calcaneus, and the mechanical axis of the hindfoot were compared using the Paired-Samples t-test. RESULTS: Thirty-two fractures were followed up for an average of 20.66 months (from 12 to 32 months). All fractures achieved stable reduction and bony union. The articular surface was reduced and fixed with direct vision through the sinus tarsi incision. No failure of internal fixation or loss of reduction was detected during follow-up. There were no soft tissue complications. Bohler's angle; the length, height, and width of the calcaneus; and the mechanical axis of the hindfoot improved significantly. The AOFAS scores averaged 84.12 points; seven cases were rated excellent, 20 good, four fair, and one poor. CONCLUSIONS: For intra-articular calcaneal fractures, minimally invasive surgery assisted with temporary LRS external fixation can reconstruct the calcaneal shape and the sub-talar articular surface. This simple surgical modality with limited complications may be helpful in the surgical treatment of most type II and III calcaneal fractures except comminuted fractures of the calcaneal tuberosity.

16.
Int J Biol Macromol ; 251: 126310, 2023 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-37579906

RESUMO

Reportedly, DNMT2/TRDMT1 mainly methylates tRNAs at C38 and prevents them from the cleavage under stress. It also plays an essential role in the survival and physiological homeostasis of organisms. Nevertheless, DNMT2/TRDMT1 exhibits much weaker tRNA methylation activity in vitro than other tRNA methyltransferases, TrmD and Trm5. Here, we explored the restricted tRNA methylation mechanism by DNMT2/TRDMT1. In the current study, the optimized buffer C at 37 °C was the best condition for DNMT2/TRDMT1 activation. Of note, Dithiothreitol (DTT) was an indispensable component for this enzyme catalysis. Moreover, reductants took similar effects on the conformation change and oligomeric formation of DNMT2/TRDMT1. Ultimately, LC-MS/MS result revealed that C292-C292 and C292-C287 were predominant intermolecular disulfide bonds in recombinant DNMT2/TRDMT1. Notably, DNMT2/TRDMT1 existed primarily as dimers via intermolecular disulfide bonds C79-C24, C292-C292, and C222-C24 in HEK293T cells. GSSG stress enhanced tRNA methylation level in the early stage of stress, whereas the DNMT2/TRDMT1 activity might be unfavorable along with this enzyme accumulation in the nucleus. Excitingly, GSH stress downregulated the DNMT2/TRDMT1 expression and promoted tRNA methylation in cells, probably through breaking intermolecular disulfide bonds in this enzyme. Thus, our findings demonstrated restricted tRNA methylation by disulfide bonds in DNMT2/TRDMT1, and will provide important implications for redox stress related-diseases.

17.
Materials (Basel) ; 16(15)2023 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-37569916

RESUMO

This study investigated the interfacial characteristics of tungsten-particle-reinforced Zr-based bulk-metallic-glass composites (Wp/Zr-BMGs) with varying tungsten-particle sizes. To this end, Wp/Zr-BMGs with three different Wp sizes were fabricated using spark plasma sintering. Subsequently, the microstructures and interfacial structures of the Wp/Zr-BMGs were extensively examined, and the mechanical properties of the microzone at the Wp/Zr-BMG interface were evaluated using a nanoindentation method. The results revealed that the interfaces of Wp/Zr-BMGs, irrespective of the Wp size, exhibited dissolution-diffusion characteristics. Moreover, the thickness of the interface diffusion layer was positively correlated to the size of Wp. The addition of Wp enhanced the elastic modulus and hardness of Zr-BMGs at the interface, as these effects are inversely related to the Wp size. Furthermore, this study established a relationship between the interfacial mechanical properties and the interfacial characteristics of particle-reinforced bulk-metallic-glass composites. Thus, this study can serve as a guide for future research in the field of Wp/Zr-BMGs and similar particle-reinforced composites.

18.
ACS Appl Mater Interfaces ; 15(31): 37327-37336, 2023 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-37505220

RESUMO

Solar-driven interfacial evaporation is an eco-friendly solution for tackling the impending water scarcity the world is facing in our century. In this work, a solar-driven interfacial evaporator was prepared from cigarette butts loaded with petroleum coke powder (Filter-PetCoke), a by-product of the oil refinery processes, for the improvement of the absorption of the incident solar light. A comparison between a flat 2D and a 3D evaporator with a surface composed of orderly patterned protrusions of 2.1 cm was carried out to assess the influence of the evaporator configuration on the evaporation performance. The 3D evaporator (3D Filter-PetCoke) achieved by far the best performance (evaporation rate: 1.97 ± 0.08 kg m-2 h-1 and solar conversion efficiency: 93.2 ± 5.4%) among the prepared samples (3D Filter-PetCoke, 3D Filter, 2D Filter-PetCoke, and 2D Filter). In addition, this configuration seems to be adaptable for real and more massive operation because of the geometry of the evaporator. The high efficiency was ascribed to the good heat generation of the petroleum coke and the excellent heat management of the 3D structure of the evaporator. Moreover, this evaporator was resistant to multiple repeated usages without significant efficiency loss and capable of producing drinking water from seawater and Escherichia coli (E. coli)-contaminated water. The findings in this work indicate that this evaporator is pertinent to real situations to supply safe freshwater very efficiently from chemically/biologically contaminated water.

19.
Heliyon ; 9(6): e17015, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37484434

RESUMO

Low-frequency oscillations (LFOs) observed in near-infrared spectroscopy (NIRS) reflect autonomic physiological processes, and may serve as useful indicators for detecting and monitoring circulatory dysfunction. The aim of this study was to reveal whether LFOs can be used as vascular perfusion biomarkers to differentiate different types and degrees of vascular lesions based on clinical patient data. Materials and Methods: In this study, healthy controls, ischemic stroke patients and peripheral atherosclerosis patients completed a resting-state LFO detection experiment. LFOs were collected simultaneously at peripheral right and left earlobes, fingertips and toes, along with coherence and phase shift analyses processing. Results: The results showed that the coherence coefficients of symmetric peripheral positions and the absolute value-phase shifts of fingers and toes can be used to distinguish healthy individuals, ischemic stroke patients and peripheral atherosclerosis patients. The symmetric earlobes' absolute value-phase shifts could be used to differentiate mild and severe ischemic stroke patients; the coherence coefficients and absolute value-phase shifts of the symmetric toes could be used to differentiate mild and severe peripheral arteriosclerosis patients. The accuracy of differentiating between types of patients was 70%; those with different degrees of peripheral atherosclerosis was 85%, and those with different degrees of ischemic stroke was 72%. Conclusions: LFOs can serve as vascular perfusion biomarkers to differentiate types and degrees of vascular lesions. Therefore, LFOs have the potential to provide valuable patient information to assist researchers and clinicians in identifying specific peripheral circulatory damage subgroups.

20.
Molecules ; 28(11)2023 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-37298755

RESUMO

Dual-ion batteries (DIBs) are a new kind of energy storage device that store energy involving the intercalation of both anions and cations on the cathode and anode simultaneously. They feature high output voltage, low cost, and good safety. Graphite was usually used as the cathode electrode because it could accommodate the intercalation of anions (i.e., PF6-, BF4-, ClO4-) at high cut-off voltages (up to 5.2 V vs. Li+/Li). The alloying-type anode of Si can react with cations and boost an extreme theoretic storage capacity of 4200 mAh g-1. Therefore, it is an efficient method to improve the energy density of DIBs by combining graphite cathodes with high-capacity silicon anodes. However, the huge volume expansion and poor electrical conductivity of Si hinders its practical application. Up to now, there have been only a few reports about exploring Si as an anode in DIBs. Herein, we prepared a strongly coupled silicon and graphene composite (Si@G) anode through in-situ electrostatic self-assembly and a post-annealing reduction process and investigated it as an anode in full DIBs together with home-made expanded graphite (EG) as a fast kinetic cathode. Half-cell tests showed that the as-prepared Si@G anode could retain a maximum specific capacity of 1182.4 mAh g-1 after 100 cycles, whereas the bare Si anode only maintained 435.8 mAh g-1. Moreover, the full Si@G//EG DIBs achieved a high energy density of 367.84 Wh kg-1 at a power density of 855.43 W kg-1. The impressed electrochemical performances could be ascribed to the controlled volume expansion and improved conductivity as well as matched kinetics between the anode and cathode. Thus, this work offers a promising exploration for high energy DIBs.


Assuntos
Grafite , Ligas , Eletrodos , Íons , Silício , Fontes de Energia Elétrica
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