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1.
Cardiovasc Diabetol ; 23(1): 129, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38622592

RESUMO

The long-term high-fat diet (HFD) can cause myocardial lipotoxicity, which is characterized pathologically by myocardial hypertrophy, fibrosis, and remodeling and clinically by cardiac dysfunction and heart failure in patients with obesity and diabetes. Circular RNAs (circRNAs), a novel class of noncoding RNA characterized by a ring formation through covalent bonds, play a critical role in various cardiovascular diseases. However, few studies have been conducted to investigate the role and mechanism of circRNA in myocardial lipotoxicity. Here, we found that circ_005077, formed by exon 2-4 of Crmp1, was significantly upregulated in the myocardium of an HFD-fed rat. Furthermore, we identified circ_005077 as a novel ferroptosis-related regulator that plays a role in palmitic acid (PA) and HFD-induced myocardial lipotoxicity in vitro and in vivo. Mechanically, circ_005077 interacted with Cyclophilin A (CyPA) and inhibited its degradation via the ubiquitination proteasome system (UBS), thus promoting the interaction between CyPA and p47phox to enhance the activity of nicotinamide adenine dinucleotide phosphate (NADPH) oxidase responsible for ROS generation, subsequently inducing ferroptosis. Therefore, our results provide new insights into the mechanisms of myocardial lipotoxicity, potentially leading to the identification of a novel therapeutic target for the treatment of myocardial lipotoxicity in the future.


Assuntos
Ciclofilina A , Dieta Hiperlipídica , Ferroptose , Animais , Ratos , Ciclofilina A/metabolismo , Miocárdio/metabolismo , Obesidade/metabolismo
2.
Indian J Ophthalmol ; 72(Suppl 3): S482-S487, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38648456

RESUMO

PURPOSE: To report the indications, surgical techniques, and outcomes of repeat keratoplasty and evaluate the risk factors for graft failure in the Chinese population. METHODS: The medical records of 216 patients (243 cases) who underwent at least two keratoplasties at a leading eye hospital in southern China between 2011 and 2020 were retrospectively reviewed. Indications and surgical procedures for repeat corneal transplantation were analyzed. Kaplan-Meier survival analysis was used to determine the graft survival rate after repeat keratoplasty. A multivariable survival model was used to assess the risk factors. RESULTS: Repeated keratoplasties increased continuously from 2011 to 2020 (P = 0.002). The most common primary indication was infectious keratitis (38.7%), and the most common reason for repeat keratoplasty was graft rejection (30.04%). Regraft techniques included penetrating keratoplasty (PK) in 165 cases (67.9%), deep lamellar keratoplasty (DALK) in 52 cases (21.40%), and endothelial keratoplasty (EK) in 26 cases (10.7%). Median survival was 5.3, 6.8, and 6.4 years for PK, DALK, and EK, respectively. The 5-year survival rate was 53.5%, 66.6%, and 69.8% for PK, DALK, and EK, respectively. The median LogMAR visual acuity was 1.4 for PK, 0.75 for DALK, and 1.2 for EK at the end of the follow-up. Multivariate analysis revealed that graft rejection is a risk factor for repeat keratoplasty failure (P = 0.002). CONCLUSIONS: DALK and EK may provide better outcomes than PK in treating graft failure. Preventing and treating postoperative graft rejection may be key to improving regraft survival. These findings will aid in the management of failed corneal grafts.

3.
Nat Commun ; 15(1): 1761, 2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38409161

RESUMO

Tissue damage elicits cell fate switching through a process called metaplasia, but how the starting cell fate is silenced and the new cell fate is activated has not been investigated in animals. In cell culture, pioneer transcription factors mediate "reprogramming" by opening new chromatin sites for expression that can attract transcription factors from the starting cell's enhancers. Here we report that SOX4 is sufficient to initiate hepatobiliary metaplasia in the adult mouse liver, closely mimicking metaplasia initiated by toxic damage to the liver. In lineage-traced cells, we assessed the timing of SOX4-mediated opening of enhancer chromatin versus enhancer decommissioning. Initially, SOX4 directly binds to and closes hepatocyte regulatory sequences via an overlapping motif with HNF4A, a hepatocyte master regulatory transcription factor. Subsequently, SOX4 exerts pioneer factor activity to open biliary regulatory sequences. The results delineate a hierarchy by which gene networks become reprogrammed under physiological conditions, providing deeper insight into the basis for cell fate transitions in animals.


Assuntos
Reprogramação Celular , Cromatina , Animais , Camundongos , Diferenciação Celular/genética , Reprogramação Celular/genética , Metaplasia , Fatores de Transcrição/metabolismo
4.
Clin Transl Med ; 14(2): e1598, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38390756

RESUMO

Despite the remarkable clinical efficacy of cancer immunotherapy, considerable patients fail to benefit from it due to primary or acquired resistance. Tumours frequently hijack diverse epigenetic mechanisms to evade immune detection, thereby highlighting the potential for pharmacologically targeting epigenetic regulators to restore the impaired immunosurveillance and re-sensitise tumours to immunotherapy. Herein, we demonstrated that KDM4-targeting chemotherapeutic drug JIB-04, epigenetically triggered the tumour-intrinsic innate immune responses and immunogenic cell death (ICD), resulting in impressive antitumour effects. Specifically, JIB-04 induced H3K9 hypermethylation through specific inhibition of the KDM4 family (KDM4A-D), leading to impaired DNA repair signalling and subsequent DNA damage. As a result, JIB-04 not only activated the tumour-intrinsic cyclic GMP-AMP synthase (cGAS)-STING pathway via DNA-damage-induced cytosolic DNA accumulation, but also promoted ICD, releasing numerous damage-associated molecular patterns. Furthermore, JIB-04 induced adaptive resistance through the upregulation of programmed death-ligand 1 (PD-L1), which could be overcome with additional PD-L1 blockade. In human tumours, KDM4B expression was negatively correlated with clinical outcomes, type I interferon signatures, and responses to immunotherapy. In conclusion, our results demonstrate that targeting KDM4 family can activate tumour-intrinsic innate sensing and immunogenicity, and synergise with immunotherapy to improve antitumour outcomes.


Assuntos
Aminopiridinas , Antígeno B7-H1 , Hidrazonas , Neoplasias , Humanos , Neoplasias/tratamento farmacológico , Neoplasias/genética , Imunidade Inata/genética , DNA/metabolismo , Histona Desmetilases com o Domínio Jumonji/genética
5.
Med Phys ; 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38299670

RESUMO

BACKGROUND: In boron neutron capture therapy (BNCT)-a form of binary radiotherapy-the primary challenge in treatment planning systems for dose calculations arises from the time-consuming nature of the Monte Carlo (MC) method. Recent progress, including the use of neural networks (NN), has been made to accelerate BNCT dose calculations. However, this approach may result in significant dose errors in both the tumor and the skin, with the latter being a critical organ in BNCT. Furthermore, owing to the lack of physical processes in purely NN-based approaches, their reliability for clinical dose calculations in BNCT is questionable. PURPOSE: In this study, a physically constrained MC-NN (PCMC-NN) coupling algorithm is proposed to achieve fast and accurate computation of the BNCT three-dimensional (3D) therapeutic dose distribution. This approach synergizes the high precision of the MC method with the speed of the NN and utilizes physical conservation laws to constrain the coupling process. It addresses the time-consuming issue of the traditional MC method while reducing dose errors. METHODS: Clinical data were collected from 113 glioblastoma patients. For each patient, the 3D dose distributions for both the coarse and detailed dose grids were calculated using the MC code PHITS. Among these patients, the data from 14 patients were allocated to the test set, 9 to the validation set, and the remaining to the training set. A neural network, 3D-Unet, was built based on the coarse grid dose and patient CT information to enable fast and accurate computation of the 3D detailed grid dose distribution of BNCT. RESULTS: Statistical evaluations, including relative deviation, dose deviation, mean absolute error (MAE), and mean absolute percentage error (MAPE) were conducted. Our findings suggested that the PCMC-NN algorithm substantially outperformed the traditional NN and interpolation methods. Furthermore, the proposed algorithm significantly reduced errors, particularly in the skin and GTV, and improved computational accuracy (hereinafter referred to simply as 'accuracy') with a MAPE range of 1.6%-4.0% and a maximum MAE of 0.3 Gy (IsoE) for different organs. The dose-volume histograms generated by the PCMC-NN aligned well with those obtained from the MC method, further validating its accuracy. CONCLUSIONS: The PCMC-NN algorithm enhanced the speed and accuracy of BNCT dose calculations by combining the MC method with the NN algorithm. This indicates the significant potential of the proposed algorithm for clinical applications in optimizing treatment planning.

6.
Nat Commun ; 15(1): 1532, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38378697

RESUMO

Acquired resistance to immunotherapy remains a critical yet incompletely understood biological mechanism. Here, using a mouse model of pancreatic ductal adenocarcinoma (PDAC) to study tumor relapse following immunotherapy-induced responses, we find that resistance is reproducibly associated with an epithelial-to-mesenchymal transition (EMT), with EMT-transcription factors ZEB1 and SNAIL functioning as master genetic and epigenetic regulators of this effect. Acquired resistance in this model is not due to immunosuppression in the tumor immune microenvironment, disruptions in the antigen presentation machinery, or altered expression of immune checkpoints. Rather, resistance is due to a tumor cell-intrinsic defect in T-cell killing. Molecularly, EMT leads to the epigenetic and transcriptional silencing of interferon regulatory factor 6 (Irf6), rendering tumor cells less sensitive to the pro-apoptotic effects of TNF-α. These findings indicate that acquired resistance to immunotherapy may be mediated by programs distinct from those governing primary resistance, including plasticity programs that render tumor cells impervious to T-cell killing.


Assuntos
Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Humanos , Linhagem Celular Tumoral , Recidiva Local de Neoplasia , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/terapia , Carcinoma Ductal Pancreático/metabolismo , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/terapia , Neoplasias Pancreáticas/metabolismo , Imunoterapia , Transição Epitelial-Mesenquimal/genética , Microambiente Tumoral
7.
ACS Appl Mater Interfaces ; 16(7): 8717-8732, 2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38326933

RESUMO

Urea electrolysis is a promising energy-efficient hydrogen production process with environmental benefits, but the lack of efficient and sustainable ampere-level current density electrocatalysts fabricated through simple methods is a major challenge for commercialization. Herein, we present an efficient and stable heterostructure electrocatalyst for full urea and water electrolysis in a convenient and time-efficient preparation manner. Overall, superhydrophilic/superaerophobic CoMn/CuNiP/NF exhibits exceptional performance for the hydrogen evolution reaction (HER) (-33.8, -184.4, and -234.8 mV at -10, -500, and -1000 mA cm-2, respectively), urea electro-oxidation reaction (UOR) [1.28, 1.43, and 1.51 V (vs RHE) at 10, 500, and 1000 mA cm-2, respectively], and oxygen evolution reaction (OER) [1.45, 1.67, and 1.74 V (vs RHE) at 10, 500, and 1000 mA cm-2, respectively]. Moreover, the superaerophobic CoMn/CuNiP/NF demonstrates promising potential in full urea (1.33, 1.57, and 1.60 V at 10, 500, and 1000 mA cm-2, respectively) and water (1.46 V, 1.78, and 1.86 at 10, 500, and 1000 mA cm-2, respectively) electrolysis. Based on X-ray photoelectron spectroscopy results, it was determined that the surface of the CoMn/CuNiP electrode was rich in redox pairs such as Ni2+/Ni3+, Cu+/Cu2+, Co2+/Co3+, and Mn2+/Mn3+, which are crucial for the formation of active sites for the OER and UOR, such as NiOOH, MnOOH, and CoOOH, thereby enhancing the catalytic activity. Besides, the in situ assembled CoMn/CuNiP/NF displayed highly stable performance for HER, OER, and UOR with high Faradaic efficiency for over 500 h. This research offers a simple and efficient method for manufacturing a high-efficiency and stable trifunctional electrocatalyst capable of delivering ampere-level current density in urea-assisted hydrogen production. Our density functional theory calculations reveal the potential of CoMn/CuNiP as an effective catalyst, enhancing the electronic properties and catalytic performance. The near-zero Gibbs free-energy change for HER underscores its promise, while reduced CO2 desorption energies and charge redistribution support efficient UOR. These findings signify CoMn/CuNiP's potential for electrochemical applications.

8.
J Biosci Bioeng ; 137(5): 360-371, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38369397

RESUMO

The unique cellar fermentation process of Chinese strong-flavor Baijiu is the reason for its characteristic cellar aroma flavor. The types, abundance, community structure and metabolic activity of microorganisms in the pit mud directly affect the microbial balance in the white spirit production environment, promoting the formation of typical aromas and influencing the quality of CFSB. During the production process, the production of off-flavor in the cellar may occur. The aim of this study is to elucidate the differences in microbiota and flavor between normal pit mud and abnormal pit mud (pit mud with off-flavor). A total of 46 major volatile compounds were identified, and 24 bacterial genera and 21 fungal genera were screened. The esters, acids, and alcohols in the abnormal pit mud were lower than those in the normal pit mud, while the aldehydes were higher. 3-Methyl indole, which has been proven to be responsible for the muddy and musty flavors, was detected in both types of pit mud, and for the first time, high levels of 4-methylanisole was detected in the pit mud. The microbial composition of the two types of pit mud showed significant differences in the bacterial genera of Sporosarcina, Lactobacillus, Garciella, Anaerosalibacter, Lentimicrobium, HN-HF0106, Petrimonas, Clostridium_sensu_stricto_12 and Bacillus, and the fungal genera of Millerozyma, Penicillium, Mortierella, Monascus, Saccharomyces, Issatchenkia, Pithoascus, Pseudallescheria, and Wickerhamomyces. Additionally, we speculate that Sporosarcina is the predominant bacterial genus responsible for the imbalance of microbiota in pit mud.


Assuntos
Microbiota , Odorantes , Odorantes/análise , Bebidas Alcoólicas/análise , Bactérias/metabolismo , Fermentação
9.
Sci Rep ; 14(1): 4792, 2024 02 27.
Artigo em Inglês | MEDLINE | ID: mdl-38413691

RESUMO

Rescues from building collapse accidents present a significant challenge for China's emergency rescue system. However, there are also many risk factors in a training scenario, which have been summarized in this study. A hierarchical indicator system for personnel safety was established, including 12 first-level indicators and 23s-level indicators. Then, an improved Grey-DEMATEL-ISM-MICMAC evaluation model was constructed to evaluate the level of risk. Influencing factor scores were determined according to the responses from the questionnaire survey. The influencing degree, influenced degree, centrality, and causality were identified, and the importance, relevance, and clustering of the various factors were obtained after making quantitative calculations. The results showed that the order of priority for solving the essential issues was safety education (A2), operating standards and proficiency (A10), equipment inspection (A4), equipment warehousing maintenance and records (A21). The solving of safety education was identified to be the most essential priority. The priority control order of direct causes was Scientific design and construction (A5), Potential fixed hazards in the facility (A12), Physical fitness of personnel (A1), Weather influences (A18), and Initiation efficiency of emergency plans (A20), and direct control measures for these five factors could achieve a relatively significant effect.


Assuntos
Colapso Estrutural , Acidentes , Fatores de Risco , Inquéritos e Questionários
10.
Insects ; 15(2)2024 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-38392551

RESUMO

Wolbachia bacteria (phylum Proteobacteria) are ubiquitous intracellular parasites of diverse invertebrates. In insects, coevolution has forged mutualistic associations with Wolbachia species, influencing reproduction, immunity, development, pathogen resistance, and overall fitness. However, the impact of Wolbachia on other microbial associates within the insect microbiome, which are crucial for host fitness, remains less explored. The diamondback moth (Plutella xylostella), a major pest of cruciferous vegetables worldwide, harbors the dominant Wolbachia strain plutWB1, known to distort its sex ratio. This study investigated the bacterial community diversity and dynamics across different developmental life stages and Wolbachia infection states in P. xylostella using high-throughput 16S rDNA amplicon sequencing. Proteobacteria and Firmicutes dominated the P. xylostella microbiome regardless of life stage or Wolbachia infection. However, the relative abundance of dominant genera, including an unclassified genus of Enterobacteriaceae, Wolbachia, Carnobacterium, and Delftia tsuruhatensis, displayed significant stage-specific variations. While significant differences in bacterial diversity and composition were observed across life stages, Wolbachia infection had no substantial impact on overall diversity. Nonetheless, relative abundances of specific genera differed between infection states. Notably, Wolbachia exhibited a stable, high relative abundance across all stages and negatively correlated with an unclassified genus of Enterobacteriaceae, Delftia tsuruhatensis, and Carnobacterium. Our findings provide a foundational understanding of the complex interplay between the host, Wolbachia, and the associated microbiome in P. xylostella, paving the way for a deeper understanding of their complex interactions and potential implications for pest control strategies.

11.
Small ; : e2400087, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38377283

RESUMO

Increasing the charging cutoff voltage of LiCoO2 to 4.6 V is significant for enhancing battery density. However, the practical application of Li‖LiCoO2 batteries with a 4.6 V cutoff voltage faces significant impediments due to the detrimental changes under high voltage. This study presents a novel bifunctional electrolyte additive, 2-(trifluoromethyl)benzamide (2-TFMBA), which is employed to establish a stable and dense cathode-electrolyte interface (CEI). Characterization results reveal that an optimized CEI is achieved through the synergistic effects of the amide groups and trifluoromethyl groups within 2-TFMBA. The resulting CEI not only enhances the structural stability of LiCoO2 but also serves as a high-speed lithium-ion conduction channel, which expedites the insertion and extraction of lithium ions. The Li‖LiCoO2 batteries with 0.5 wt% 2-TFMBA achieves an 84.7% capacity retention rate after enduring 300 cycles at a current rate of 1 C, under a cut-off voltage of 4.6 V. This study provides valuable strategic insights into the stabilization of cathode materials in high-voltage batteries.

12.
Exp Eye Res ; 239: 109778, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38171475

RESUMO

Human embryonic stem cell (hESC)- and human induced pluripotent stem cell (hiPSC)-derived retinal pigment epithelium (RPE) therapies are promising alternatives for the treatment of retinal degenerative diseases caused by RPE degeneration. The generation of autologous RPE cells from human adult donors, which has the advantage of avoiding immune rejection and teratoma formation, is an alternative cell resource to gain mechanistic insight into and test potential therapies for RPE degenerative diseases. Here, we found that limbal stem cells (LSCs) from hESCs and adult primary human limbus have the potential to produce RPE cells and corneal stromal stem cells (CSSCs). We showed that hESC-LSC-derived RPE cells (LSC-RPE) expressed RPE markers, had a phagocytic function, and synthesized tropical factors. Furthermore, during differentiation from LSCs to RPE cells, cells became pigmented, accompanied by a decrease in the level of LSC marker KRT15 and an increase in the level of RPE marker MITF. The Wnt signaling pathway plays a role in LSC-RPE fate transition, promotes MITF expression in the nucleus, and encourages RPE fate transition. In addition, we also showed that primary LSCs (pLSCs) from adult human limbus similar to hESC-LSC could generate RPE cells, which was supported by the co-expression of LSC and RPE cell markers (KRT15/OTX2, KRT15/MITF), suggesting the transition from pLSC to RPE cells, and typical polygonal morphology, melanization, RPE cell marker genes expression (TYR, RPE65), tight junction formation by ZO-1 expression, and the most crucial phagocytotic function. On the other hand, both hESC-LSCs and pLSCs also differentiated into CSSCs (LSC-CSSCs) that expressed stem cell markers (PAX6, NESTIN), presented MSC features, including surface marker expression and trilineage differentiation capability, like those in human CSSCs. Furthermore, the capability of pLSC-CSSC to differentiate into cells expressing keratocyte marker genes (ALDH3A1, PTGDS, PDK4) indicated the potential to induce keratocytes. These results suggest that the adult pLSC is an alternative cell resource, and its application provides a novel potential therapeutic avenue for preventing RPE dysfunction-related retinal degenerative diseases and corneal scarring.


Assuntos
Células-Tronco Pluripotentes Induzidas , Células-Tronco do Limbo , Humanos , Células-Tronco Pluripotentes Induzidas/metabolismo , Epitélio Pigmentado da Retina/metabolismo , Diferenciação Celular , Células Epiteliais/metabolismo , Pigmentos da Retina/metabolismo
13.
Nat Cancer ; 5(1): 131-146, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38168934

RESUMO

Availability of the essential amino acid methionine affects cellular metabolism and growth, and dietary methionine restriction has been implicated as a cancer therapeutic strategy. Nevertheless, how liver cancer cells respond to methionine deprivation and underlying mechanisms remain unclear. Here we find that human liver cancer cells undergo irreversible cell cycle arrest upon methionine deprivation in vitro. Blocking methionine adenosyl transferase 2A (MAT2A)-dependent methionine catabolism induces cell cycle arrest and DNA damage in liver cancer cells, resulting in cellular senescence. A pharmacological screen further identified GSK3 inhibitors as senolytics that selectively kill MAT2A-inhibited senescent liver cancer cells. Importantly, combined treatment with MAT2A and GSK3 inhibitors therapeutically blunts liver tumor growth in vitro and in vivo across multiple models. Together, methionine catabolism is essential for liver tumor growth, and its inhibition can be exploited as an improved pro-senescence strategy for combination with senolytic agents to treat liver cancer.


Assuntos
Quinase 3 da Glicogênio Sintase , Neoplasias Hepáticas , Humanos , S-Adenosilmetionina/metabolismo , S-Adenosilmetionina/farmacologia , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/genética , Metionina/farmacologia , Metionina Adenosiltransferase/metabolismo
14.
ACS Omega ; 9(3): 3746-3757, 2024 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-38284029

RESUMO

Most dust suppressants used for buildings currently lack sufficient resistance to harsh conditions, such as high temperatures and wind erosion. To solve this problem, it is necessary to develop a new type of dust suppressant. In this study, the guar gum molecule was chemically modified to remove the active hydroxyl group in order to significantly improve the stability and adhesion of guar gum. Eventually, a composite dust suppressant was synthesized by incorporating a surfactant and an absorbent agent into modified guar gum. The functional groups of the reaction products were analyzed via infrared experiments, thus confirming the success of the modification. Wind erosion resistance and scanning electron microscopy experiments confirmed the improved bonding capabilities of the composite dust suppressant with dust particles. In experiments on wind erosion resistance, the dust fixation rate exceeded 50% after the application of the composite dust suppressant. The results of the thermogravimetric tests showed that the maximum mass loss rate of the samples with modified guar gum dust suppressants was 6.0% and 28% lower than those of the samples with unmodified guar gum dust suppressants and water, respectively. Furthermore, the tests conducted on pH value and corrosion resistance indicated that the pH value of this dust suppressant was comparable to that of tap water and demonstrated a similar rate of metal corrosion. The practical significance of this study is to improve the dust suppressant used in buildings, to improve the performance of dust suppressant and resistance to harsh environment, and to help to continuously improve the health of personnel and environmental protection during construction. The practical significance of this study is to improve the dust suppressant used in buildings, to improve the performance of dust suppressant and resistance to harsh environments, and to help to continuously improve the health of personnel and environmental protection during construction, which has positive practical significance for the building industry and related fields.

15.
Phys Chem Chem Phys ; 26(5): 4159-4165, 2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38230417

RESUMO

Topological quasiparticles have garnered significant research attention in condensed matter physics. However, they are exceedingly rare in two-dimensional systems, particularly those hosting unconventional topological quasiparticles. In this work, employing first-principles calculations and symmetry analysis, we demonstrate that PtS, PtSe, and PtTe monolayers serve as high-quality two-dimensional topological semimetal materials. These materials exhibit multiple types of topological quasiparticles around the Fermi level in the absence of spin-orbit coupling, such as conventional linear Weyl points and unconventional quadratic Weyl points in the PtS monolayer, as well as nodal loops in PtSe and PtTe monolayers. When spin-orbit coupling (SOC) is introduced, a tiny gap opens, transforming the systems into quantum spin hall insulators. Simultaneously, three spin-orbit Dirac points, robust against SOC, appear at the X, Y, and M points. We illustrate the symmetry protection, low-energy effective model, and edge states of these topological states. Our work provides an excellent material platform for studying novel two-dimensional topological quasiparticles and topological insulators.

16.
Int J Biol Macromol ; 258(Pt 1): 128293, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38000587

RESUMO

Periodontitis is an oral disease with the highest incidence globally, and plaque control is the key to its treatment. In this study, Microcin C7 was used to treat periodontitis, and a novel injectable temperature-sensitive sustained-release hydrogel was synthesized as an environmentally sensitive carrier for drug delivery. First, modified gelatin was formed from gelatin and glycidyl methacrylate. Then, Microcin C7-laden hydrogel was formed from cross-linking with double bonds between modified gelatin, N-isopropyl acrylamide, and 2-Methacryloyloxyethyl phosphorylcholine through radical polymerization, and the model drug Microcin C7 was loaded by electrostatic adsorption. The hydrogel has good temperature sensitivity, self-healing, and injectable properties. In vitro results showed that the hydrogel could slowly and continuously release Microcin C7 with good biocompatibility and biodegradability, with a remarkable antibacterial effect on Porphyromonas gingivalis. It also confirmed the antibacterial and anti-inflammatory effects of Microcin C7-laden hydrogel in a periodontitis rat model. The results showed that Microcin C7-laden hydrogel is a promising candidate for local drug delivery systems in periodontitis.


Assuntos
Bacteriocinas , Hidrogéis , Periodontite , Ratos , Animais , Hidrogéis/química , Gelatina/química , Antibacterianos/farmacologia , Periodontite/tratamento farmacológico
17.
Nat Commun ; 14(1): 8514, 2023 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-38129428

RESUMO

Microelectronic devices can directly communicate with biology, as electronic information can be transmitted via redox reactions within biological systems. By engineering biology's native redox networks, we enable electronic interrogation and control of biological systems at several hierarchical levels: proteins, cells, and cell consortia. First, electro-biofabrication facilitates on-device biological component assembly. Then, electrode-actuated redox data transmission and redox-linked synthetic biology allows programming of enzyme activity and closed-loop electrogenetic control of cellular function. Specifically, horseradish peroxidase is assembled onto interdigitated electrodes where electrode-generated hydrogen peroxide controls its activity. E. coli's stress response regulon, oxyRS, is rewired to enable algorithm-based feedback control of gene expression, including an eCRISPR module that switches cell-cell quorum sensing communication from one autoinducer to another-creating an electronically controlled 'bilingual' cell. Then, these disparate redox-guided devices are wirelessly connected, enabling real-time communication and user-based control. We suggest these methodologies will help us to better understand and develop sophisticated control for biology.


Assuntos
Escherichia coli , Proteínas , Escherichia coli/genética , Escherichia coli/metabolismo , Retroalimentação , Proteínas/metabolismo , Eletrônica , Oxirredução
18.
Microb Cell Fact ; 22(1): 236, 2023 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-37974259

RESUMO

BACKGROUND: Thermophilic fungus Myceliophthora thermophila has been widely used in industrial applications due to its ability to produce various enzymes. However, the lack of an efficient protein expression system has limited its biotechnological applications. RESULTS: In this study, using a laccase gene reporting system, we developed an efficient protein expression system in M. thermophila through the selection of strong constitutive promoters, 5'UTRs and signal peptides. The expression of the laccase was confirmed by enzyme activity assays. The results showed that the Mtpdc promoter (Ppdc) was able to drive high-level expression of the target protein in M. thermophila. Manipulation of the 5'UTR also has significant effects on protein expression and secretion. The best 5'UTR (NCA-7d) was identified. The transformant containing the laccase gene under the Mtpdc promoter, NCA-7d 5'UTR and its own signal peptide with the highest laccase activity (1708 U/L) was obtained. In addition, the expression system was stable and could be used for the production of various proteins, including homologous proteins like MtCbh-1, MtGh5-1, MtLPMO9B, and MtEpl1, as well as a glucoamylase from Trichoderma reesei. CONCLUSIONS: An efficient protein expression system was established in M. thermophila for the production of various proteins. This study provides a valuable tool for protein production in M. thermophila and expands its potential for biotechnological applications.


Assuntos
Lacase , Sordariales , Lacase/genética , Lacase/metabolismo , Regiões 5' não Traduzidas/genética , Regiões Promotoras Genéticas , Sordariales/genética , Sordariales/metabolismo
19.
J Nanobiotechnology ; 21(1): 382, 2023 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-37858171

RESUMO

Lack of proper innate sensing inside the tumor microenvironment could reduce both innate and adaptive immunity, which remains a critical cause of immunotherapy failure in various tumor treatments. Double-stranded DNA (dsDNA) has been evidenced to be a promising immunostimulatory agent to induce type I interferons (IFN-Is) production for innate immunity activation through the cyclic GMP-AMP synthase (cGAS)-stimulator of interferon genes (STING) signaling pathway, yet the unsatisfactory delivery and susceptibility to nuclease degradation hindered its feasibility for further clinical applications. Herein, we report on the constructed tumor microenvironment-responsive DNA-based nanomedicine loaded by dendritic mesoporous organosilica nanoparticles (DMONs), which provide efficient delivery of dsDNA to induce intratumoral IFN-Is production for triggering innate sensing for enhanced anti-tumor immunotherapy. Extensive in vitro and in vivo evaluations have demonstrated the dramatic IFN-Is production induced by dsDNA@DMONs in both immune cells and tumor cells, which facilitates dendritic cells (DCs) maturation and T cells activation for eliciting the potent innate immune and adaptive immune responses. Desirable biosafety and marked therapeutic efficacy with a tumor growth inhibition (TGI) of 51.0% on the murine B16-F10 melanoma model were achieved by the single agent dsDNA@DMONs. Moreover, dsDNA@DMONs combined with anti-PD-L1 antibody further enhanced the anti-tumor efficacy and led to almost complete tumor regression. Therefore, this work highlighted the immunostimulatory DNA-based nanomedicine as a promising strategy for overcoming the resistance to immunotherapy, by promoting the IFN-Is production for innate immunity activation and remodeling the tumor microenvironment.


Assuntos
Neoplasias , Microambiente Tumoral , Camundongos , Animais , Humanos , Nanomedicina , Imunidade Inata , DNA , Imunoterapia , Neoplasias/terapia
20.
Adv Sci (Weinh) ; 10(35): e2305550, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37828611

RESUMO

Effective treatment for metastasis, a leading cause of cancer-associated death, is still lacking. To seed on a distal organ, disseminated cancer cells (DCCs) must adapt to the local tissue microenvironment. However, it remains elusive how DCCs respond the pro-metastatic niche signals. Here, systemic motif-enrichment identified myocyte enhancer factor 2D (MEF2D) as a critical sensor of niche signals to regulate DCCs adhesion and colonization, leading to intrahepatic metastasis and recurrence of liver cancer. In this context, MEF2D transactivates Itgb1 (coding ß1-integrin) and Itgb4 (coding ß4-integrin) to execute temporally unique functions, where ITGB1 recognizes extracellular matrix for early seeding, and ITGB4 acts as a novel sensor of neutrophil extracellular traps-DNA (NETs-DNA) for subsequent chemotaxis and colonization. In turn, an integrin-FAK circuit promotes a phosphorylation-dependent USP14-orchastrated deubiquitination switch to stabilize MEF2D via circumventing degradation by the E3-ubiquitin-ligase MDM2. Clinically, the USP14(pS432)-MEF2D-ITGB1/4 feedback loop is often hyper-active and indicative of inferior outcomes in human malignancies, while its blockade abrogated intrahepatic metastasis of DCCs. Together, DCCs exploit a deubiquitination-dependent switch on MEF2D to integrate niche signals in the liver mesenchyme, thereby amplifying the pro-metastatic integrin-FAK signaling. Disruption of this feedback loop is clinically applicable with fast-track potential to block microenvironmental cues driving metastasis.


Assuntos
Neoplasias Hepáticas , Ubiquitina , Humanos , Fatores de Transcrição MEF2/genética , Fatores de Transcrição MEF2/metabolismo , Integrinas , DNA , Microambiente Tumoral , Ubiquitina Tiolesterase
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