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1.
Chem Commun (Camb) ; 2024 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-38984894

RESUMEN

A through-space charge transfer pyrene-based fluorophore has been developed for organic light-emitting devices (OLEDs). This material exhibits deep-blue fluorescence, bipolar characteristics, and anti-quenching behavior in the solid state. It proves to be an effective emitter for both doped and nondoped deep-blue OLEDs.

2.
Angew Chem Int Ed Engl ; : e202406677, 2024 Jun 02.
Artículo en Inglés | MEDLINE | ID: mdl-38825572

RESUMEN

The microtubule-associated protein tau participates in neurotransmission regulation via its interaction with synaptic vesicles (SVs). The precise nature and mechanics of tau's engagement with SVs, especially regarding alterations in vesicle dynamics, remain a matter of discussion. We report an electrochemical method using a synapse-mimicking nanopipette to monitor vesicle dynamics induced by tau. A model vesicle of ~30 nm is confined within a lipid-modified nanopipette orifice with a comparable diameter to mimic the synaptic lipid environment. Both tau and phosphorylated tau (p-tau) present two-state dynamic behavior in this biomimetic system, showing typical ionic current oscillation, induced by lipid-tau interaction. The results indicate that p-tau has a stronger affinity to the lipid vesicles in the confined environment, blocking the vesicle movement to a higher degree. Taken together, this method bridges a gap for sensing synaptic vesicle dynamics in a confined lipid environment, mimicking vesicle movement near the synaptic membrane. These findings contribute to understanding how different types of tau protein regulate synaptic vesicle motility and to underlying its functional and pathological behaviours in disease.

3.
Analyst ; 149(9): 2629-2636, 2024 Apr 29.
Artículo en Inglés | MEDLINE | ID: mdl-38563459

RESUMEN

Cell migration is known to be a fundamental biological process, playing an essential role in development, homeostasis, and diseases. This paper introduces a cell tracking algorithm named HFM-Tracker (Hybrid Feature Matching Tracker) that automatically identifies cell migration behaviours in consecutive images. It combines Contour Attention (CA) and Adaptive Confusion Matrix (ACM) modules to accurately capture cell contours in each image and track the dynamic behaviors of migrating cells in the field of view. Cells are firstly located and identified via the CA module-based cell detection network, and then associated and tracked via a cell tracking algorithm employing a hybrid feature-matching strategy. This proposed HFM-Tracker exhibits superiorities in cell detection and tracking, achieving 75% in MOTA (Multiple Object Tracking Accuracy) and 65% in IDF1 (ID F1 score). It provides quantitative analysis of the cell morphology and migration features, which could further help in understanding the complicated and diverse cell migration processes.


Asunto(s)
Algoritmos , Movimiento Celular , Rastreo Celular , Rastreo Celular/métodos , Humanos , Procesamiento de Imagen Asistido por Computador/métodos
4.
ACS Meas Sci Au ; 4(1): 76-80, 2024 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-38404487

RESUMEN

Reactions involving sulfhydryl groups play a critical role in maintaining the structure and function of proteins. However, traditional mechanistic studies have mainly focused on reaction rates and the efficiency in bulk solutions. Herein, we have designed a cysteine-mutated nanopore as a biological protein nanoreactor for electrochemical visualization of the thiol substitute reaction. Statistical analysis of characteristic current signals shows that the apparent reaction rate at the single-molecule level in this confined nanoreactor reached 1400 times higher than that observed in bulk solution. This substantial acceleration of thiol substitution reactions within the nanopore offers promising opportunities for advancing the design and optimization of micro/nanoreactors. Moreover, our results could shed light on the understanding of sulfhydryl reactions and the thiol-involved signal transduction mechanisms in biological systems.

5.
BMC Cancer ; 24(1): 253, 2024 Feb 23.
Artículo en Inglés | MEDLINE | ID: mdl-38395798

RESUMEN

BACKGROUND: Cancer cachexia is associated with impaired functional and nutritional status and worse clinical outcomes. Global Leadership Initiative in Malnutrition (GLIM) consensus recommended the application of GLIM criteria to diagnose malnutrition in patients with cachexia. However, few previous study has applied the GLIM criteria in patients with cancer cachexia. METHODS: From July 2014 to May 2019, patients who were diagnosed with cancer cachexia and underwent radical gastrectomy for gastric cancer were included in this study. Malnutrition was diagnosed using the GLIM criteria. Skeletal muscle index was measured using abdominal computed tomography (CT) images at the third lumbar vertebra (L3) level. Hand-grip strength and 6-meters gait speed were measured before surgery. RESULTS: A total of 356 patients with cancer cachexia were included in the present study, in which 269 (75.56%) were identified as having malnutrition based on the GLIM criteria. GLIM-defined malnutrition alone did not show significant association with short-term postoperative outcomes, including complications, costs or length of postoperative hospital stays. The combination of low hand-grip strength or low gait speed with GLIM-defined malnutrition led to a significant predictive value for these outcomes. Moreover, low hand-grip strength plus GLIM-defined malnutrition was independently associated with postoperative complications (OR 1.912, 95% CI 1.151-3.178, P = 0.012). GLIM-defined malnutrition was an independent predictive factor for worse OS (HR 2.310, 95% CI 1.421-3.754, P = 0.001) and DFS (HR 1.815, 95% CI 1.186-2.779, P = 0.006) after surgery. The addition of low hand-grip strength or low gait speed to GLIM-defined malnutrition did not increase its predictive value for survival. CONCLUSION: GLIM-defined malnutrition predicted worse long-term survival in gastric cancer patients with cachexia. Gait speed and hand-grip strength added prognostic value to GLIM-defined malnutrition for the prediction of short-term postoperative outcomes, which could be incorporated into preoperative assessment protocols in patients with cancer cachexia.


Asunto(s)
Desnutrición , Neoplasias Gástricas , Humanos , Caquexia/diagnóstico , Caquexia/etiología , Pronóstico , Neoplasias Gástricas/complicaciones , Neoplasias Gástricas/cirugía , Liderazgo , Velocidad al Caminar , Desnutrición/complicaciones , Desnutrición/diagnóstico , Estado Nutricional , Fuerza de la Mano , Evaluación Nutricional
6.
Angew Chem Int Ed Engl ; 63(17): e202316551, 2024 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-38411372

RESUMEN

Single-entity electrochemistry is a powerful tool that enables the study of electrochemical processes at interfaces and provides insights into the intrinsic chemical and structural heterogeneities of individual entities. Signal processing is a critical aspect of single-entity electrochemical measurements and can be used for data recognition, classification, and interpretation. In this review, we summarize the recent five-year advances in signal processing techniques for single-entity electrochemistry and highlight their importance in obtaining high-quality data and extracting effective features from electrochemical signals, which are generally applicable in single-entity electrochemistry. Moreover, we shed light on electrochemical noise analysis to obtain single-molecule frequency fingerprint spectra that can provide rich information about the ion networks at the interface. By incorporating advanced data analysis tools and artificial intelligence algorithms, single-entity electrochemical measurements would revolutionize the field of single-entity analysis, leading to new fundamental discoveries.

7.
Mol Cell ; 84(3): 570-583.e7, 2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-38215752

RESUMEN

Adhesion G protein-coupled receptors (aGPCRs) are evolutionarily ancient receptors involved in a variety of physiological and pathophysiological processes. Modulators of aGPCR, particularly antagonists, hold therapeutic promise for diseases like cancer and immune and neurological disorders. Hindered by the inactive state structural information, our understanding of antagonist development and aGPCR activation faces challenges. Here, we report the cryo-electron microscopy structures of human CD97, a prototypical aGPCR that plays crucial roles in immune system, in its inactive apo and G13-bound fully active states. Compared with other family GPCRs, CD97 adopts a compact inactive conformation with a constrained ligand pocket. Activation induces significant conformational changes for both extracellular and intracellular sides, creating larger cavities for Stachel sequence binding and G13 engagement. Integrated with functional and metadynamics analyses, our study provides significant mechanistic insights into the activation and signaling of aGPCRs, paving the way for future drug discovery efforts.


Asunto(s)
Antígenos CD , Receptores Acoplados a Proteínas G , Transducción de Señal , Humanos , Adhesión Celular , Microscopía por Crioelectrón , Complejo GPIb-IX de Glicoproteína Plaquetaria , Receptores Acoplados a Proteínas G/química , Receptores Acoplados a Proteínas G/metabolismo , Antígenos CD/química , Antígenos CD/metabolismo
8.
Clin Exp Pharmacol Physiol ; 51(1): 10-16, 2024 01.
Artículo en Inglés | MEDLINE | ID: mdl-37806661

RESUMEN

Bronchoscopic lung volume reduction (BLVR) is a feasible, safe, effective and minimally invasive technique to significantly improve the quality of life of advanced severe chronic obstructive pulmonary disease (COPD). In this study, three-dimensional computed tomography (3D-CT) automatic analysis software combined with pulmonary function test (PFT) was used to retrospectively evaluate the postoperative efficacy of BLVR patients. The purpose is to evaluate the improvement of lung function of local lung tissue after operation, maximize the benefits of patients, and facilitate BLVR in the treatment of patients with advanced COPD. All the reported cases of advanced COPD patients treated with BLVR with one-way valve were collected and analysed from 2017 to 2020. Three-dimensional-CT image analysis software system was used to analyse the distribution of low-density areas <950 Hounsfield units in both lungs pre- and post- BLVR. Meanwhile, all patients performed standard PFT pre- and post-operation for retrospective analysis. We reported six patients that underwent unilateral BLVR with 1 to 3 valves according to the range of emphysema. All patients showed a median increase in forced expiratory volume in 1 second (FEV1) of 34%, compared with baseline values. Hyperinflation was reduced by 16.6% (range, 4.9%-47.2%). The volumetric measurements showed a significant reduction in the treated lobe volume among these patients. Meanwhile, the targeted lobe volume changes were inversely correlated with change in FEV1/FEV1% in patients with heterogeneous emphysematous. We confirm that 3D-CT analysis can quantify the changes of lung volume, ventilation and perfusion, to accurately evaluate the distribution and improvement of emphysema and rely less on the observer.


Asunto(s)
Enfisema , Enfermedad Pulmonar Obstructiva Crónica , Enfisema Pulmonar , Humanos , Neumonectomía/efectos adversos , Neumonectomía/métodos , Estudios Retrospectivos , Calidad de Vida , Pulmón/diagnóstico por imagen , Pulmón/cirugía , Enfisema Pulmonar/diagnóstico por imagen , Enfisema Pulmonar/cirugía , Enfisema Pulmonar/etiología , Enfermedad Pulmonar Obstructiva Crónica/diagnóstico por imagen , Enfermedad Pulmonar Obstructiva Crónica/cirugía , Enfisema/diagnóstico por imagen , Enfisema/cirugía , Enfisema/etiología , Tomografía Computarizada por Rayos X/métodos , Resultado del Tratamiento
9.
Mikrochim Acta ; 191(1): 8, 2023 Dec 06.
Artículo en Inglés | MEDLINE | ID: mdl-38052768

RESUMEN

Surface-enhanced Raman scattering (SERS) has been recognized as one of the most sensitive analytical methods by adsorbing the target of interest onto a plasmonic surface. Growing attention has been directed towards the fabrication of various substrates to broaden SERS applications. Among these, flexible SERS substrates, particularly paper-based ones, have gained popularity due to their easy-to-use features by full contact with the sample surface. Herein, we reviewed the latest advancements in flexible SERS substrates, with a focus on paper-based substrates. Firstly, it begins by introducing various methods for preparing paper-based substrates and highlights their advantages through several illustrative examples. Subsequently, we demonstrated the booming applications of these paper-based SERS substrates in abiotic and biological matrix detection, with particular emphasis on their potential application in clinical diagnosis. Finally, the prospects and challenges of paper-based SERS substrates in broader applications are discussed.

10.
World J Gastroenterol ; 29(34): 5038-5053, 2023 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-37753370

RESUMEN

BACKGROUND: Hepatocellular carcinoma (HCC) is a common clinical condition with a poor prognosis and few effective treatment options. Potent anticancer agents for treating HCC must be identified. Epigenetics plays an essential role in HCC tumorigenesis. Suberoylanilide hydroxamic acid (SAHA), the most common histone deacetylase inhibitor agent, triggers many forms of cell death in HCC. However, the underlying mechanism of action remains unclear. Family with sequence similarity 134 member B (FAM134B)-induced reticulophagy, a selective autophagic pathway, participates in the decision of cell fate and exhibits anticancer activity. This study focused on the relationship between FAM134B-induced reticulophagy and SAHA-mediated cell death. AIM: To elucidate potential roles and underlying molecular mechanisms of reticulophagy in SAHA-induced HCC cell death. METHODS: The viability, apoptosis, cell cycle, migration, and invasion of SAHA-treated Huh7 and MHCC97L cells were measured. Proteins related to the reticulophagy pathway, mitochondria-endoplasmic reticulum (ER) contact sites, intrinsic mitochondrial apoptosis, and histone acetylation were quantified using western blotting. ER and lysosome colocalization, and mitochondrial Ca2+ levels were characterized via confocal microscopy. The level of cell death was evaluated through Hoechst 33342 staining and propidium iodide colocalization. Chromatin immunoprecipitation was used to verify histone H4 lysine-16 acetylation in the FAM134B promoter region. RESULTS: After SAHA treatment, the proliferation of Huh7 and MHCC97L cells was significantly inhibited, and the migration and invasion abilities were greatly blocked in vitro. This promoted apoptosis and caused G1 phase cells to increase in a concentration-dependent manner. Following treatment with SAHA, ER-phagy was activated, thereby triggering autophagy-mediated cell death of HCC cells in vitro. Western blotting and chromatin immunoprecipitation assays confirmed that SAHA regulated FAM134B expression by enhancing the histone H4 lysine-16 acetylation in the FAM134B promoter region. Further, SAHA disturbed the Ca2+ homeostasis and upregulated the level of autocrine motility factor receptor and proteins related to mitochondria-endoplasmic reticulum contact sites in HCC cells. Additionally, SAHA decreased the mitochondrial membrane potential levels, thereby accelerating the activation of the reticulophagy-mediated mitochondrial apoptosis pathway and promoting HCC cell death in vitro. CONCLUSION: SAHA stimulates FAM134B-mediated ER-phagy to synergistically enhance the mitochondrial apoptotic pathway, thereby enhancing HCC cell death.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Vorinostat/farmacología , Carcinoma Hepatocelular/tratamiento farmacológico , Carcinoma Hepatocelular/genética , Histonas , Lisina , Neoplasias Hepáticas/tratamiento farmacológico , Neoplasias Hepáticas/genética , Muerte Celular , Autofagia
11.
BMC Complement Med Ther ; 23(1): 304, 2023 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-37648989

RESUMEN

INTRODUCTION: Allergic rhinitis is a global health problem that can potentially be managed through acupressure. Our clinical observations have identified Allergic Rhinitis Acupressure Therapeutic (ARAT) as a novel acupressure treatment acting on specific acupoints, which may enhance the effectiveness of acupressure. Therefore, we propose a three-arm randomized controlled trial will be conducted to investigate the efficacy and safety of ARAT for perennial allergic rhinitis (PAR). METHODS/DESIGN: In this trial, eligible 111 participants diagnosed with PAR will be randomly assigned to one of three groups: the ARAT group, the non-specific acupoints group, or the blank control group. The primary outcome will be the change in the total nasal symptom score, and the secondary outcomes will include: 1) changes in the scores of the standard version of Rhinoconjunctivitis Quality of Life Questionnaire (RQLQs); 2) acoustic rhinometry and anterior rhinomanometry; 3) changes in the scores of relief medication usage; 4) incidence of adverse events. Additionally, we will measure and compare the changes in cytokine levels (IL-5, IL-13, IFN-γ, and TSLP) in nasal secretions. The RQLQs and primary outcomes will be assessed at the beginning, middle, and end stages of the treatment period, with monthly follow-ups conducted over a total of three months. The secondary outcomes and biomarkers in nasal secretions will be measured at the beginning and end of the treatment period. Any adverse events or need for rescue medication will be carefully noted and recorded. DISCUSSION: This study may produce a new acupressure treatment prescription that is easy to learn, more targeted, and adaptable. This trial represents the first clinical investigation comparing ARAT treatment for PAR with the non-specific acupoints group and blank control group. Our data is expected to provide evidence demonstrating the safety and efficacy of ARAT for PAR patients, while also exploring the functional mechanism underlying ARAT treatment, moreover, the results offer valuable insights for healthcare professionals in managing PAR symptoms. TRIAL REGISTRATION: Chinese Clinical Trial Registry, ChiCTR2300072292. Registered on June 08, 2023.


Asunto(s)
Acupresión , Rinitis Alérgica , Humanos , Calidad de Vida , Mucosa Nasal , Rinitis Alérgica/terapia , Puntos de Acupuntura , Ensayos Clínicos Controlados Aleatorios como Asunto
12.
Front Microbiol ; 14: 1071603, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37275170

RESUMEN

Modifying and transforming natural antibacterial products is a novel idea for developing new efficacious compounds. Phillygenin has an inhibitory effect on H. pylori. The aim of the present study was to prepare a phillygenin derivative (PHI-Der) through demethylation and hydroxylation. The minimum inhibitory concentration of 18 strains of H. pylori from different sources was 8-32 µg/mL in vitro, and the activity increased 2-8 times than that of phillygenin. PHI-Der could significantly inhibit the colonization of H. pylori in vivo, reduce the inflammatory response, and promote the repair of inflammatory damage. Further, we used SwissTargetPrediction to predict that its main targets are ALOX5, MCL1, and SLC6A4, and find that it can inhibit bacterial biofilm formation and reduce bacterial infection of cells. It can enhance the intracellular oxidative capacity of H. pylori to inhibit H. pylori growth. Further, it could prevent the oxidation of H. pylori-infected cells and reduce the inflammatory response, which plays a role in protection. In conclusion, compared to phillygenin, PHI-Der had better antibacterial activity and was more effective in treating H. pylori infection. It has characteristics of high safety, specificity, resistance to drug resistance and better antibacterial activity than phillygenin, it's a good antioxidant for host cells.

13.
Front Public Health ; 11: 1170085, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37250088

RESUMEN

Purpose: The study aimed to identify potential risk factors for family transmission and to provide precautionary guidelines for the general public during novel Coronavirus disease 2019 (COVID-19) waves. Methods: A retrospective cohort study with numerous COVID-19 patients recruited was conducted in Shanghai. Epidemiological data including transmission details, demographics, vaccination status, symptoms, comorbidities, antigen test, living environment, residential ventilation, disinfection and medical treatment of each participant were collected and risk factors for family transmission were determined. Results: A total of 2,334 COVID-19 patients participated. Compared with non-cohabitation infected patients, cohabitated ones were younger (p = 0.019), more commonly unvaccinated (p = 0.048) or exposed to infections (p < 0.001), and had higher rates of symptoms (p = 0.003) or shared living room (p < 0.001). Risk factors analysis showed that the 2019-nCov antigen positive (OR = 1.86, 95%CI 1.40-2.48, p < 0.001), symptoms development (OR = 1.86, 95%CI 1.34-2.58, p < 0.001), direct contact exposure (OR = 1.47, 95%CI 1.09-1.96, p = 0.010) were independent risk factors for the cohabitant transmission of COVID-19, and a separate room with a separate toilet could reduce the risk of family transmission (OR = 0.62, 95%CI 0.41-0.92, p = 0.018). Conclusion: Patients showing negative 2019-nCov antigen tests, being asymptomatic, living in a separate room with a separate toilet, or actively avoiding direct contact with cohabitants were at low risk of family transmission, and the study recommended that avoiding direct contact and residential disinfection could reduce the risk of all cohabitants within the same house being infected with COVID-19.


Asunto(s)
COVID-19 , Humanos , COVID-19/epidemiología , Cuarentena , Estudios Retrospectivos , China/epidemiología , Factores de Riesgo
14.
Angew Chem Int Ed Engl ; 62(27): e202304023, 2023 07 03.
Artículo en Inglés | MEDLINE | ID: mdl-37115672

RESUMEN

Disulfide bonds play an important role in thiol-based redox regulation. However, owing to the lack of analytical tools, little is known about how local O2 mediates the reversible thiol/disulfide cycle under protein confinement. In this study, a protein-nanopore inside a glove box is used to control local O2 for single-molecule reaction, as well as a single-molecule sensor for real-time monitoring of the reversible thiol/disulfide cycle. The results demonstrate that the local O2 molecules in protein nanopores could facilitate the redox cycle of disulfide formation and cleavage by promoting a higher fraction of effective reactant collisions owing to nanoconfinement. Further kinetic calculations indicate that the negatively charged residues near reactive sites facilitate proton-involved oxygen-induced disulfide cleavage under protein confinement. The unexpectedly strong oxidation ability of confined local O2 may play an essential role in cellular redox signaling and enzyme reactions.


Asunto(s)
Nanoporos , Compuestos de Sulfhidrilo , Compuestos de Sulfhidrilo/química , Disulfuros/química , Oxígeno , Proteínas/química , Oxidación-Reducción
15.
Research (Wash D C) ; 6: 0019, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37040505

RESUMEN

Heart failure (HF), leading as one of the main causes of mortality, has become a serious public health issue with high prevalence around the world. Single cardiomyocyte (CM) metabolomics promises to revolutionize the understanding of HF pathogenesis since the metabolic remodeling in the human hearts plays a vital role in the disease progression. Unfortunately, current metabolic analysis is often limited by the dynamic features of metabolites and the critical needs for high-quality isolated CMs. Here, high-quality CMs were directly isolated from transgenic HF mice biopsies and further employed in the cellular metabolic analysis. The lipids landscape in individual CMs was profiled with a delayed extraction mode in time-of-flight secondary ion mass spectrometry. Specific metabolic signatures were identified to distinguish HF CMs from the control subjects, presenting as possible single-cell biomarkers. The spatial distributions of these signatures were imaged in single cells, and those were further found to be strongly associated with lipoprotein metabolism, transmembrane transport, and signal transduction. Taken together, we systematically studied the lipid metabolism of single CMs with a mass spectrometry imaging method, which directly benefited the identification of HF-associated signatures and a deeper understanding of HF-related metabolic pathways.

16.
Nanoscale ; 15(16): 7261-7266, 2023 Apr 27.
Artículo en Inglés | MEDLINE | ID: mdl-37038732

RESUMEN

We developed a bipolar SiNx nanopore for the observation of single-molecule heterogeneous enzymatic dynamics. Single glucose oxidase was immobilized inside the nanopore and its electrocatalytic behaviour was real-time monitored via continuous recording of ionic flux amplification. The temporal heterogeneity in enzymatic properties and its spatial dynamic orientations were observed simultaneously, and these two properties were found to be closely correlated. We anticipate that this method offers new perspectives on the correlation of protein structure and function at the single-molecule level.


Asunto(s)
Nanoporos , Proteínas/química , Glucosa Oxidasa , Nanotecnología , Iones
17.
Chem Soc Rev ; 52(8): 2596-2616, 2023 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-36994760

RESUMEN

Molecular structure conversion concomitant with mass transfer processes at the electrode-electrolyte interfaces plays a central role in energy electrochemistry. Mass spectrometry, as one of the most intuitive, sensitive techniques, provides the capability to collect transient intermediates and products and uncover reaction mechanisms and kinetics. In situ time-of-flight secondary ion electrochemical mass spectrometry with inherent high mass and spatiotemporal resolution has emerged as a promising strategy for investigating electrochemical processes at the electrode surface. This review illustrates the recent advancements in coupling time-of-flight secondary ion mass spectrometry and electrochemistry to visualize and quantify local dynamic electrochemical processes, identify solvated species distribution, and disclose hidden reaction pathways at the molecular level. Moreover, the key challenges in this field are further discussed to promote new applications and discoveries in operando studying the dynamic electrochemical interfaces of advanced energy systems.

18.
Chemistry ; 29(27): e202203919, 2023 May 11.
Artículo en Inglés | MEDLINE | ID: mdl-36787024

RESUMEN

Sequence-defined polymer is one of the most promising alternative media for high-density data storage. It could be used to alleviate the problem of insufficient storage capacity of conventional silicon-based devices for the explosively increasing data. To fulfil the goal of polymer data storage, suitable methods should be developed to accurately read and decode the information-containing polymers, especially for those composed by a combination of the natural and unnatural monomers. Nanopore-based approaches have become one of the most competitive analysis and sequencing techniques, which are expected to read both natural and synthetic polymers with single-molecule precision and monomeric resolution. Herein, this work emphasizes the advances being made in nanopore reading and decoding of information stored in the man-made polymers and DNA nanostructures, and discusses the challenges and opportunities towards the development and realization of high-density data storage.

19.
Neural Regen Res ; 18(6): 1308-1315, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36453416

RESUMEN

Recent studies have indicated that suppressing oxidative stress and ferroptosis can considerably improve the prognosis of intracerebral hemorrhage (ICH). Withaferin A (WFA), a natural compound, exhibits a positive effect on a number of neurological diseases. However, the effects of WFA on oxidative stress and ferroptosis-mediated signaling pathways to ICH remain unknown. In this study, we investigated the neuroprotective effects and underlying mechanism for WFA in the regulation of ICH-induced oxidative stress and ferroptosis. We established a mouse model of ICH by injection of autologous tail artery blood into the caudate nucleus and an in vitro cell model of hemin-induced ICH. WFA was injected intracerebroventricularly at 0.1, 1 or 5 µg/kg once daily for 7 days, starting immediately after ICH operation. WFA markedly reduced brain tissue injury and iron deposition and improved neurological function in a dose-dependent manner 7 days after cerebral hemorrhage. Through in vitro experiments, cell viability test showed that WFA protected SH-SY5Y neuronal cells against hemin-induced cell injury. Enzyme-linked immunosorbent assays in vitro and in vivo showed that WFA markedly decreased the level of malondialdehyde, an oxidative stress marker, and increased the activities of anti-oxidative stress markers superoxide dismutase and glutathione peroxidase after ICH. Western blot assay, quantitative polymerase chain reaction and immunofluorescence results demonstrated that WFA activated the nuclear factor E2-related factor 2 (Nrf2)/heme oxygenase-1 (HO-1) signaling axis, promoted translocation of Nrf2 from the cytoplasm to nucleus, and increased HO-1 expression. Silencing Nrf2 with siRNA completely reversed HO-1 expression, oxidative stress and protective effects of WFA. Furthermore, WFA reduced hemin-induced ferroptosis. However, after treatment with an HO-1 inhibitor, the neuroprotective effects of WFA against hemin-induced ferroptosis were weakened. MTT test results showed that WFA combined with ferrostatin-1 reduced hemin-induced SH-SY5Y neuronal cell injury. Our findings reveal that WFA treatment alleviated ICH injury-induced ferroptosis and oxidative stress through activating the Nrf2/HO-1 pathway, which may highlight a potential role of WFA for the treatment of ICH.

20.
Chem Asian J ; 18(3): e202201144, 2023 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-36527379

RESUMEN

RNA modifications modulate essential cellular functions. However, it is challenging to quantitatively identify the differences in RNA modifications. To further improve the single-molecule sensing ability of nanopores, we propose a machine-learning algorithm called SmartImage for identifying and classifying nanopore electrochemical signals based on a combination of improved graph conversion methods and deep neural networks. SmartImage is effective for nearly all ranges of signal duration, which breaks the limitation of the current nanopore algorithm. The overall accuracy (OA) of our proposed recognition strategy exceeded 90% for identifying three types of RNAs. Prediction experiments show that the SmartImage owns the ability to recognize one modified RNA molecule from 1000 normal RNAs with OA >90%. Thus our proposed model and algorithm hold the potential application in clinical applications.


Asunto(s)
Nanoporos , ARN , Aprendizaje Automático
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