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1.
Liver Int ; 2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-38554044

RESUMO

BACKGROUND: Liver ischaemia/reperfusion (I/R) injury, which is an inevitable clinical problem of liver resection, liver transplantation and haemorrhagic shock. Fibroblast growth factor 21 (FGF21) was intimately coupled with multiple metabolic processes and proved to protect against apoptosis and inflammatory response in hepatocytes during hepatic I/R injury. However, the regulatory mechanisms of FGF21 in hepatic I/R injury remains unknown. Therefore, we hypothesize that FGF21 protects hepatic tissues from I/R injury. METHODS: Blood samples were available from haemangiomas patients undergoing hepatectomy and murine liver I/R model and used to further evaluate the serum levels of FGF21 both in humans and mice. We further explored the regulatory mechanisms of FGF21 in murine liver I/R model by using FGF21-knockout mice (FGF21-KO mice) and FGF21-overexpression transgenic mice (FGF21-OE mice) fed a high-fat or ketogenic diet. RESULTS: Our results show that the circulating levels of FGF21 were robustly decreased after liver I/R in both humans and mice. Silencing FGF21 expression with FGF21-KO mice aggravates liver injury at 6 h after 75 min of partial liver ischaemia, while FGF21-OE mice display alleviated hepatic I/R injury and inflammatory response. Compared with chow diet mice, exogenous FGF21 decreases the levels of aminotransferase, histological changes, apoptosis and inflammatory response in hepatic I/R injury treatment mice with a high-fat diet. Meanwhile, ketogenic diet mice are not sensitive to hepatic I/R injury. CONCLUSIONS: The circulating contents of FGF21 are decreased during liver warm I/R injury and exogenous FGF21 exerts hepatoprotective effects on hepatic I/R injury. Thus, FGF21 regulates hepatic I/R injury and may be a key therapeutic target.

2.
Talanta ; 273: 125946, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38508127

RESUMO

The sensitivity and repeatability are crucial for the practical application of electrochemical sensors. Many studies have focused on sensing materials and electrode structure to enhance sensitivity and repeatability rather than insulating layers. In this paper, polyaniline (PANI) microelectrode arrays were prepared to explore the influence of the insulating layer on sensitivity and repeatability of electrochemical sensors. The effects of different types of insulating layers, the sizes of the electrodes, and the thicknesses of the insulating layers were studied by experiment and simulation. The research findings indicated that the kind of organic insulating layers (Polyimide (PI) and SU-8) did not have a significant effect on the performance of the sensors. However, as the electrode area increased, the PANI film deposited on the electrode exhibited improved uniformity and density, leading to significant improvements in sensitivity and repeatability of the sensors. Additionally, the thickness of the insulating layer also had a significant impact on the performance of the device. The microelectrode with thinner insulating layers exhibited improved performance in sensitivity, repeatability and signal-to-noise ratio. The research findings indicated that increasing the electrode size and reducing the thickness of the insulating layer led to a more uniform and dense PANI film, resulting in an array electrode that exhibits excellent performance and remarkable repeatability.

3.
Artigo em Inglês | MEDLINE | ID: mdl-38195353

RESUMO

OBJECTIVE: To investigate the value of magnetic resonance imaging (MRI) signal intensity ratios (SIRs) based on fat-suppressed T2-weighted imaging (FS-T2WI), together with demographic features, MRI anatomical characteristics, and SIRs of histopathological patterns of the tumors, in the differentiation of parotid pleomorphic adenoma (PA) from Warthin tumor (WT). STUDY DESIGN: In total, 90 patients with PA and 56 patients with WT were enrolled in the study. SIRs of tumor to normal parotid gland (SIR-T/P), spinal cord (SIR-T/S), and muscle (SIR-T/M) were calculated. Demographic and radiological features of the 2-patient groups were compared with univariate analysis and multivariate logistic regression analysis. The area under the receiver operating characteristic curve (AUC), sensitivity, and specificity were analyzed to evaluate the utility of SIRs in distinguishing between PA and WT. RESULTS: SIR-T/P exhibited outstanding discriminating ability (AUC = 0.934), SIR-T/S had excellent discrimination (AUC = 0.839), and SIR-T/M showed acceptable discrimination (AUC = 0.728). When SIR-T/P of 1.96 was selected as the cutoff value, sensitivity and specificity were 0.756 and 0.982, respectively. SIR-T/P, age, sex, and number of lesions were identified as independent predictors by multivariate logistic regression analysis. Differences in SIRs between histopathological patterns were significant. CONCLUSION: SIR-T/P based on FS-T2WI is an effective discriminator in the differential diagnosis between PA and WT. Age, sex, and number of lesions provided additional value in differentiation.


Assuntos
Adenolinfoma , Adenoma Pleomorfo , Neoplasias das Glândulas Salivares , Humanos , Adenoma Pleomorfo/patologia , Adenolinfoma/diagnóstico por imagem , Adenolinfoma/patologia , Imageamento por Ressonância Magnética/métodos , Glândula Parótida/patologia
4.
Phys Chem Chem Phys ; 26(6): 5115-5127, 2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38259173

RESUMO

The hydration process of cement-based materials primarily results in the formation of calcium silicate hydrate (CSH), which is crucial in deciding how long concrete will last. This study utilizes molecular dynamics simulation technology to explore the freezing behavior of pure water solutions within various calcium silicate hydrate (CSH) matrices. The investigated matrices encompass four different Ca/Si ratios. According to the simulation, as ice crystals develop close to the surface of CSH, the CSH matrix strengthens its hydrogen and ionic interactions with water molecules, which effectively prevents water molecules from crystallizing and nucleating. Consequently, these molecules compose an unfrozen water film structure that bridges between ice crystals and the CSH matrix. The research also reveals an intriguing relationship between silica chain behavior on the Ca/Si ratio and the CSH surface. Surface flaws arise as a result of the silica chains of CSH breaking into shorter segments as the Ca/Si ratio increases. These surface defects manifest as grooves on the matrix's surface, effectively capturing and retaining specific water molecules. The CSH matrix's hydrogen bonds with water molecules are weakened as a result of this process, facilitating their participation in the crystallization process, and leading to a thinner unfrozen water film thickness with an increased Ca/Si ratio. This study contributes to a greater knowledge of the performance and dependability of cement-based products by offering molecular-level insights into the freezing actions of liquids in gel pores.

5.
Anal Chem ; 96(5): 2087-2093, 2024 02 06.
Artigo em Inglês | MEDLINE | ID: mdl-38275169

RESUMO

Due to its direct effect on biomolecules and cells, electrical stimulation (ES) is now widely used to regulate cell proliferation, differentiation, and neurostimulation and is even used in the clinic for pain relief, treatment of nerve damage, and muscle rehabilitation. Conventional ES is mostly studied on cell populations, but the heterogeneity of cancer cells results in the inability to access the response of individual cells to ES. Therefore, detecting the extracellular pH change (ΔpHe) after ES at the single-cell level is important for the application of ES in tumor therapy. In this study, cellular ΔpHe after periodic impulse electrostimulation (IES) was monitored in situ by using a polyaniline (PANI)-modified gold microelectrode array. The PANI sensor had excellent sensitivity (53.68 mV/pH) and linear correlation coefficient (R2 = 0.999) over the pH range of 5.55-7.41. The cells showed different degrees of ΔpHe after the IES with different intervals and stimulation potential. A shorter pulse interval and a higher stimulation potential could effectively enhance stimulation and increase cellular ΔpHe. At 0.5 V potential stimulation, the cellular ΔpHe increased with decreasing pulse interval. However, if the pulse interval was long enough, even at a higher potential of 0.7 V, there was no significant additional ΔpHe due to the insufficient stimulus strength. Based on the above conclusions, the prepared PANI microelectrode arrays (MEAs) were capable of stimulating and detecting single cells, which contributed to the deeper application of ES in tumor therapy.


Assuntos
Neoplasias , Humanos , Microeletrodos , Diferenciação Celular/fisiologia , Estimulação Elétrica/métodos , Concentração de Íons de Hidrogênio
6.
Cancer Sci ; 115(3): 777-790, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38228495

RESUMO

Intrahepatic cholangiocarcinoma (ICC) is a highly malignant and aggressive cancer whose incidence and mortality continue to increase, whereas its prognosis remains dismal. Tumor-associated macrophages (TAMs) promote malignant progression and immune microenvironment remodeling through direct contact and secreted mediators. Targeting TAMs has emerged as a promising strategy for ICC treatment. Here, we revealed the potential regulatory function of immune responsive gene 1 (IRG1) in macrophage polarization. We found that IRG1 expression remained at a low level in M2 macrophages. IRG1 overexpression can restrain macrophages from polarizing to the M2 type, which results in inhibition of the proliferation, invasion, and migration of ICC, whereas IRG1 knockdown exerts the opposite effects. Mechanistically, IRG1 inhibited the tumor-promoting chemokine CCL18 and thus suppressed ICC progression by regulating STAT3 phosphorylation. The intervention of IRG1 expression in TAMs may serve as a potential therapeutic target for delaying ICC progression.


Assuntos
Neoplasias dos Ductos Biliares , Colangiocarcinoma , Humanos , Colangiocarcinoma/patologia , Macrófagos/metabolismo , Prognóstico , Ductos Biliares Intra-Hepáticos/metabolismo , Neoplasias dos Ductos Biliares/patologia , Linhagem Celular Tumoral , Microambiente Tumoral , Quimiocinas CC/metabolismo , Fator de Transcrição STAT3/metabolismo
7.
World J Pediatr ; 2023 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-38070095

RESUMO

BACKGROUND: Surgery plays an important role in the treatment of neuroblastoma. Perioperative complications may impact the course of neuroblastoma treatment. To date, comprehensive analyses of complications and risk factors have been lacking. METHODS: Patients with retroperitoneal neuroblastoma undergoing tumor resection were retrospectively analyzed between 2014 and 2021. The data collected included clinical characteristics, operative details, operative complications and postoperative outcomes. Risk factors for perioperative complications of retroperitoneal neuroblastoma were analyzed. RESULTS: A total of 571 patients were enrolled in this study. Perioperative complications were observed in 255 (44.7%) patients. Lymphatic leakage (28.4%), diarrhea (13.5%), and injury (vascular, nerve and organ; 7.5%) were the most frequent complications. There were three operation-related deaths (0.53%): massive hemorrhage (n = 1), biliary tract perforation (n = 1) and intestinal necrosis (n = 1). The presence of image-defined risk factors (IDRFs) [odds ratio (OR) = 2.09, P < 0.01], high stage of the International Neuroblastoma Risk Group staging system (INRGSS) (OR = 0.454, P = 0.04), retroperitoneal lymph node metastasis (OR = 2.433, P = 0.026), superior mesenteric artery encasement (OR = 3.346, P = 0.003), and inferior mesenteric artery encasement (OR = 2.218, P = 0.019) were identified as independent risk factors for perioperative complications. CONCLUSIONS: Despite the high incidence of perioperative complications, the associated mortality rate was quite low. Perioperative complications of retroperitoneal neuroblastoma were associated with IDRFs, INRGSS, retroperitoneal lymph node metastasis and vascular encasement. Patients with high-risk factors should receive more serious attention during surgery but should not discourage the determination to pursue total resection of neuroblastoma. Video Abstract (MP4 94289 KB).

8.
Materials (Basel) ; 16(23)2023 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-38068021

RESUMO

Anthracite-associated graphite is an important graphite resource with a wide range of applications besides being used as a fuel. This paper introduces a method for evaluating the graphite equivalent evaluation of anthracite-associated graphite. A series of graphite-anthracite standard samples with known graphite content were prepared, and their Raman spectra were obtained using a Raman spectrometer. By employing peak-fitting analysis to decipher the peak spectrum information of the D peak and G peak, trends in the peak position, peak intensity ratio, half-width, and peak area of the D peak and G peak in standard samples with different graphite contents were obtained. Subsequently, a standard curve and fitting equation were established using the peak area data. The goodness of fit for the equation (R2) was 0.9984. Then the equation was used to evaluate 100 natural anthracite-associated graphite samples with unknown graphite content, obtaining a corresponding graphite equivalent evaluation.

9.
J Exp Clin Cancer Res ; 42(1): 286, 2023 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-37891677

RESUMO

BACKGROUND: The endoplasmic reticulum (ER) regulates critical processes, including lipid synthesis, which are affected by transmembrane proteins localized in the ER membrane. One such protein, transmembrane protein 147 (TMEM147), has recently been implicated for its role in hepatocellular carcinoma (HCC) tumorigenesis; however, the mechanisms remain unclear. We investigated the role of TMEM147 in HCC and the underlying mechanisms. METHODS: TMEM147 expression was examined in human HCC cells and adjacent non-tumorous tissues using quantitative reverse transcription-polymerase chain reaction, western blotting, and immunohistochemistry. In vitro and in vivo studies were conducted to investigate the impact of TMEM147 on the progression of HCC. Proteins interacting with TMEM147 were identified via RNA-seq, immunoprecipitation, and mass spectrometry analyses. Lipidomic analysis and enzyme-linked immunosorbent assay (ELISA) were employed to determine and analyze cholesterol and 27-hydroxycholesterol (27HC) contents. Extensive experimental techniques were used to study ferroptosis in HCC cells. The fatty acid content of macrophages affected by TMEM147 was quantified using ELISA. Macrophage phenotypes were determined using immunofluorescence assay and flow cytometric analysis. RESULTS: TMEM147 mRNA and protein levels were increased in HCC cells, and the increased TMEM147 expression was associated with a poor survival. TMEM147 promoted tumor cell proliferation and metastases in vitro and in vivo. The protein was found to interact with the key enzyme 7-dehydrocholesterol reductase (DHCR7), which affected cellular cholesterol homeostasis and increased the extracellular levels of 27HC in HCC cells. TMEM147 also promoted the expression of DHCR7 by enhancing the activity of signal transducer and activator of transcription 2. 27HC expression upregulated glutathione peroxidase 4 in HCC, leading to ferroptosis resistance and promotion of HCC proliferation. HCC cell-derived 27HC expression increased the lipid metabolism in macrophages and activated peroxisome proliferator-activated receptor-γ signaling, thereby activating M2 macrophage polarization and promoting HCC cell invasion and migration. CONCLUSIONS: Our results indicate that TMEM147 confers ferroptosis resistance and M2 macrophage polarization, which are primarily dependent on the upregulation of cellular cholesterol homeostasis and 27HC secretion, leading to cancer growth and metastasis. These findings suggest that the TMEM147/STAT2/DHCR7/27HC axis in the tumor microenvironment may serve as a promising therapeutic target for HCC.


Assuntos
Carcinoma Hepatocelular , Ferroptose , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/patologia , Macrófagos Associados a Tumor/metabolismo , Linhagem Celular Tumoral , Metabolismo dos Lipídeos , Microambiente Tumoral
10.
Sci Rep ; 13(1): 15919, 2023 09 23.
Artigo em Inglês | MEDLINE | ID: mdl-37741887

RESUMO

Pancreatic cancer is one of the tumors with the worst prognosis, causing serious harm to human health. The RNA network and immune response play an important role in tumor progression. While a systematic RNA network linked to the tumor immune response remains to be further explored in pancreatic cancer. Based on The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) databases, the MIR600HG/hsa-miR-342-3p/ANLN network was determined. WB and IHC were used to confirm the high expression of ANLN in pancreatic cancer. The prognostic model based on the RNA network could effectively predict the survival prognosis of patients. The analysis of immune infiltration showed that the MIR600HG/hsa-miR-342-3p/ANLN network altered the level of infiltration of T helper 2 (Th2) and effector memory T (Tem) cells. Furthermore, we found that the chemokines chemokine ligand (CCL) 5 and CCL14 may play a key role in immune cell infiltration mediated by the RNA network. In conclusion, this study constructed a prognostic model based on the MIR600HG/hsa-miR-342-3p/ANLN network and found that it may function in tumor immunity.


Assuntos
MicroRNAs , Neoplasias Pancreáticas , Humanos , MicroRNAs/genética , Neoplasias Pancreáticas/genética , Biomarcadores , Neoplasias Pancreáticas
11.
Analyst ; 148(18): 4525-4532, 2023 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-37581262

RESUMO

The zeolitic imidazole framework with a leaf-shaped morphology (ZIF-L) has a wide range of promising applications in gas storage, battery materials, catalytic reactions, and optoelectronic devices due to its planar leaf-like structure and large surface area. However, the low conductivity, weak catalytic activity, and poor stability in the water dielectric medium of ZIF-L limit its further practical application. To solve these problems, we added the conductive polymer heterocyclic poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) to ZIF-L for the sensitive detection of dopamine (DA). The synthesized composite ZIF-L/PEDOT:PSS (ZIF-L/PEDOT) not only retained the surface morphology of ZIF-L but also exhibited excellent electrochemical properties. The higher electrical conductivity of ZIF-L/PEDOT than that of ZIF-L was due to the enhanced electron transfer at the interface between ZIF-L and PEDOT:PSS. As a result, we developed an electrochemical biosensor based on the ZIF-L/PEDOT composite, which has a limit of detection of 7 nM for DA and a wide linear range from 25 nM to 500 µM. Furthermore, the current drop was negligible after 28 days, proving that the biosensor has excellent stability. Based on the above-mentioned outstanding performance, the ZIF-L/PEDOT-based biosensor was successfully used to detect DA in human serum samples. These results demonstrated that ZIF-L/PEDOT is expected to play an essential role in disease detection.


Assuntos
Dopamina , Polímeros , Humanos , Polímeros/química , Condutividade Elétrica , Imidazóis
12.
JMIR Public Health Surveill ; 9: e48449, 2023 09 21.
Artigo em Inglês | MEDLINE | ID: mdl-37560940

RESUMO

BACKGROUND: Little is known about trends in or projections of the disease burden of dietary gastric and esophageal cancer (GEC) in China. OBJECTIVE: We aim to report GEC deaths and disability-adjusted life years (DALYs) from 1990 to 2019, predict them through 2044, and decompose changes in terms of population growth, population aging, and epidemiological changes. METHODS: We retrieved dietary GEC data from the Global Burden of Disease (GBD) online database and used joinpoint regression and age-period-cohort models to analyze trends in dietary GEC deaths and DALYs from 1990 to 2019 in China. We used a Bayesian age period cohort model of integrated nested Laplace approximations to predict the disease burden of GEC through 2044 and obtained the estimated population of China from 2020 to 2050 from the Global Health Data Exchange website. Finally, we applied a recently developed decomposition method to attribute changes between 2019 and 2044 to population growth, population aging, and epidemiological changes. RESULTS: The summary exposure values and age-standardized rates decreased significantly from 1990 to 1999, with percentage changes of -0.06% (95% CI -0.11% to -0.02%) and -0.05% (95% CI -0.1% to -0.02%), respectively. From 1990 to 2019, for dietary esophageal cancer, the percentage change in age-standardized mortality rate (ASMR) was -0.79% (95% CI -0.93% to -0.58%) and the percentage change in age-standardized DALY rate (ASDR) was -0.81% (95% CI -0.94% to -0.61%); these were significant decreases. For dietary stomach cancer, significant decreases were also observed for the percentage change in ASMR (-0.43%, 95% CI -0.55% to -0.31%) and the percentage change in ASDR (-0.47%, 95% CI -0.58% to -0.35%). In addition, data from both the joinpoint regression and annual percentage change analyses demonstrated significantly decreasing trends for the annual percentage change in ASMR and ASDR for GEC attributable to dietary carcinogens. The overall annual percentage change (net drift) was -5.95% (95% CI -6.25% to -5.65%) for dietary esophageal cancer mortality and -1.97% (95% CI -2.11% to -1.83%) for dietary stomach cancer mortality. Lastly, in 2044, dietary esophageal cancer deaths and DALYs were predicted to increase by 192.62% and 170.28%, respectively, due to age structure (121.58% and 83.29%), mortality change (76.81% and 92.43%), and population size (-5.77% and -5.44%). In addition, dietary stomach cancer deaths and DALYs were predicted to increase by 118.1% and 54.08%, with age structure, mortality rate change, and population size accounting for 96.71% and 53.99%, 26.17% and 3.97%, and -4.78% and -3.88% of the change, respectively. CONCLUSIONS: Although the predicted age-standardized rates of mortality and DALYs due to dietary GEC show downward trends, the absolute numbers are still predicted to increase in the next 25 years due to rapid population aging in China.


Assuntos
Neoplasias Esofágicas , Neoplasias Gástricas , Humanos , Adulto , Neoplasias Esofágicas/epidemiologia , Neoplasias Gástricas/epidemiologia , Teorema de Bayes , China/epidemiologia , Carcinógenos
13.
Phys Chem Chem Phys ; 25(32): 21684-21698, 2023 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-37551777

RESUMO

A systematic quantum-chemical study of the hydrogenation of ethene, catalyzed by strong acids HX (X = F, Cl, Br) and superacids HA (A = MgX3, Mg2X5; X = F, Cl, Br) arising from octet superhalogens is explored. Two possible paths are proposed, concerted and stepwise, and the calculated results show that the concerted path is more favorable than the stepwise path. Compared to the hydrogenation reaction without any catalyst, the improvement of the catalytic efficiency of the superacid HA (A = MgX3, Mg2X5) is high, up to 38.8 to 59.4%. Compared to the strong acid HX (X = F, Cl, Br), the barrier energy is significantly reduced and the improvement of the catalytic efficiency of the superacid HA reaches 23.1 to 31.7%. In particular, for HMg2Br5, the barrier energy of the hydrogenation of ethene is only 36 kcal mol-1, which shows that the reaction could proceed under experimental conditions. In addition, the results show that the catalytic efficiency of the superacid HA is related to the acidity of the superacid. In general, the greater the acidity, the lower the barrier energy and the easier the hydrogenation reaction. From the analysis of the bond order, the newly formed C-H bond of the transition state (TS3) in the concerted path, in which the H atom comes from the superacid catalyst, directly affects the barrier energy of the entire reaction. For the more acidic catalyst, this H atom is provided more easily, and then the formed C-H bond in the transition state is stronger. Consequently, this stronger bond leads to a more stable transition state, and hence to a lower energy barrier as well as a higher efficiency of the superacid catalyst. Therefore, a positive correlation between the acidity of the metal-free catalyst and its catalytic efficiency is expected in the hydrogenation reaction.

14.
Science ; 381(6659): 784-790, 2023 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-37498987

RESUMO

Photoluminescent molecules and nanomaterials have potential applications as active waveguides, but such a use has often been limited by high optical losses and complex fabrication processes. We explored ligand-protected metal nanoclusters (LPMNCs), which can have strong, stable, and tunable emission, as waveguides. Two alloy LPMNCs, Pt1Ag18 and AuxAg19-x (7 ≤ x ≤ 9), were synthesized and structurally determined. Crystals of both exhibited excellent optical waveguide performance, with optical loss coefficients of 5.26 × 10-3 and 7.77 × 10-3 decibels per micrometer, respectively, lower than those demonstrated by most inorganic, organic, and hybrid materials. The crystal packing and molecular orientation of the Pt1Ag18 compound led to an extremely high polarization ratio of 0.91. Aggregation enhanced the quantum yields of Pt1Ag18 and AuxAg19-x LPMNCs by 115- and 1.5-fold, respectively. This photonic cluster with low loss and high polarization provides a generalizable and versatile platform for active waveguides and polarizable materials.

15.
Chem Sci ; 14(26): 7304-7309, 2023 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-37416707

RESUMO

Metal nanoclusters are excellent electrochemiluminescent luminophores owing to their rich electrochemical and optical properties. However, the optical activity of their electrochemiluminescence (ECL) is unknown. Herein, we achieved, for the first time, the integration of optical activity and ECL, i.e., circularly polarized electrochemiluminescence (CPECL), in a pair of chiral Au9Ag4 metal nanocluster enantiomers. Chiral ligand induction and alloying were employed to endow the racemic nanoclusters with chirality and photoelectrochemical reactivity. S-Au9Ag4 and R-Au9Ag4 exhibited chirality and bright-red emission (quantum yield = 4.2%) in the ground and excited states. The enantiomers showed mirror-imaged CPECL signals at 805 nm owing to their highly intense and stable ECL emission in the presence of tripropylamine as a co-reactant. The ECL dissymmetry factor of the enantiomers at 805 nm was calculated to be ±3 × 10-3, which is comparable with that obtained from their photoluminescence. The obtained nanocluster CPECL platform shows the discrimination of chiral 2-chloropropionic acid. The integration of optical activity and ECL in metal nanoclusters provides the opportunity to achieve enantiomer discrimination and local chirality detection with high sensitivity and contrast.

16.
Phys Chem Chem Phys ; 25(27): 18387-18399, 2023 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-37401358

RESUMO

Single-molecule magnets (SMMs) have great potential in becoming revolutionary materials for micro-electronic devices. As one type of SMM and holding the performance record, lanthanide single-ion magnets (Ln-SIMs) stand at the forefront of the family. Lowering the coordination number (CN) is an important strategy to improve the performance of Ln-SIMs. Here, we report a theoretical study on a typical group of low-CN Ln-SIMs, i.e., tetracoordinated structures. Our results are consistent with those of experiments and they identify the same three best Ln-SIMs via a concise criterion, i.e., the co-existence of long τQTM and high Ueff. Compared to the record-holding dysprosocenium systems, the best SIMs here possess τQTM values that are shorter by several orders of magnitude and Ueff values that are lower by ∼1000 Kelvin (K). These are important reasons for the fact that the tetracoordinated Ln-SIMs are clearly inferior to dysprosocenium. A simple but intuitive crystal-field analysis leads to several routes to improve the performance of a given Ln-SIM, including compression of the axial bond length, widening the axial bond angle, elongation of the equatorial bond length and usage of weaker equatorial donor ligands. Although these routes are not brand-new, the most efficient option and the degree of improvement resulting from it are not known in advance. Consequently, a theoretical magneto-structural study, covering various routes, is carried out for the best Ln-SIM here and the most efficient route is shown to be widening the axial ∠O-Dy-O angle. The most optimistic case, having a ∠O-Dy-O of 180°, could have a τQTM (up to 103 s) and Ueff (∼2400 K) close to those of the record-holders. Subsequently, a blocking temperature (TB) of 64 K is predicted to be possible for it. A more practical case, with ∠O-Dy-O being 160°, could have a τQTM of up to 400 s, Ueff of around 2200 K and the possibility of a TB of 57 K. Although having an inherent precision limit, these predictions provide a guide to performance improvement, starting from an existing system.

17.
Exploration (Beijing) ; 3(1): 20210233, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37323621

RESUMO

Graphene is a 2D material with fruitful electrical properties, which can be efficiently prepared, tailored, and modified for a variety of applications, particularly in the field of optoelectronic devices thanks to its planar hexagonal lattice structure. To date, graphene has been prepared using a variety of bottom-up growth and top-down exfoliation techniques. To prepare high-quality graphene with high yield, a variety of physical exfoliation methods, such as mechanical exfoliation, anode bonding exfoliation, and metal-assisted exfoliation, have been developed. To adjust the properties of graphene, different tailoring processes have been emerged to precisely pattern graphene, such as gas etching and electron beam lithography. Due to the differences in reactivity and thermal stability of different regions, anisotropic tailoring of graphene can be achieved by using gases as the etchant. To meet practical requirements, further chemical functionalization at the edge and basal plane of graphene has been extensively utilized to modify its properties. The integration and application of graphene devices is facilitated by the combination of graphene preparation, tailoring, and modification. This review focuses on several important strategies for graphene preparation, tailoring, and modification that have recently been developed, providing a foundation for its potential applications.

18.
J Orthop Sci ; 2023 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-37330353

RESUMO

BACKGROUND: For patients with rotator cuff tear (RCT), the contra-lateral shoulders have higher risk of RCT than general population. It has been proved by several previous studies. The focus of this study is to obtain the data of contra-lateral rotator cuff tear in Chinese population, and to find the rules of contra-lateral rotator cuff tear through statistical analysis. METHODS: From March 2016 to January 2020, patients who underwent shoulder arthroscopic surgery were included in the study, we conduct bilateral shoulder ultrasound before surgery, patients information collection include gender, age, occupation and whether received contra-lateral rotator cuff surgery within 1-3 years. The above information was statistically analyzed. RESULTS: According to the inclusion and exclusion criteria, 401 patients were included. The incidence of contra-lateral rotator cuff tear was 24.3%, 5.58% of them underwent contra-lateral rotator cuff repair surgery within 3 years. The degree of contra-lateral rotator cuff tear was positively correlated with the degree of the primary side; Patients with full-thickness rotator cuff tear were more likely to have contra-lateral rotator cuff tear than patients with partial rotator cuff tear. For patients with supraspinatus tendon tear, the contra-lateral rotator cuff tear risk increases, For patients with subscapularis muscle tear, the contra-lateral rotator cuff tear risk doesn't increases. Contra-lateral rotator cuff tear is related to age, the risk of contra-lateral rotator cuff tear is higher in elderly patients. CONCLUSIONS: The contra-lateral RCT data obtained in our study was 24.3%, significantly lower than that of previous studies. The reasons may include ethnic variation, lifestyle, and proportion of heavy physical labor. The condition of contra-lateral rotator cuff is closely related to affected side rotator cuff tear.

19.
Oncogene ; 42(24): 2017-2030, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37142680

RESUMO

Hepatocellular carcinoma (HCC) is one of the most deadly malignant cancers worldwide. Research into the crucial genes responsible for maintaining the aggressive behaviour of cancer cells is important for the clinical treatment of HCC. The purpose of this study was to determine whether the E3 ubiquitin ligase Ring Finger Protein 125 (RNF125) plays a role in the proliferation and metastasis of HCC. RNF125 expression in human HCC samples and cell lines was investigated using TCGA dataset mining, qRT‒PCR, western blot, and immunohistochemistry assays. In addition, 80 patients with HCC were studied for the clinical value of RNF125. Furthermore, the molecular mechanism by which RNF125 contributes to hepatocellular carcinoma progression was determined with mass spectrometry (MS), coimmunoprecipitation (Co-IP), dual-luciferase reporter assays, and ubiquitin ladder assays. We found that RNF125 was markedly downregulated in HCC tumour tissues, which was associated with a poor prognosis for patients with HCC. Moreover, the overexpression of RNF125 inhibited HCC proliferation and metastasis both in vitro and in vivo, whereas the knockdown of RNF125 exerted antithetical effects. Mechanistically, mass spectrometry analysis revealed a protein interaction between RNF125 and SRSF1, and RNF125 accelerated the proteasome-mediated degradation of SRSF1, which impeded HCC progression by inhibiting the ERK signalling pathway. Furthermore, RNF125 was detected to be the downstream target of miR-103a-3p. In this study, we identified that RNF125 is a tumour suppressor in HCC and inhibits HCC progression by inhibiting the SRSF1/ERK pathway. These findings provide a promising treatment target for HCC.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , MicroRNAs , Humanos , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/patologia , Sistema de Sinalização das MAP Quinases , Linhagem Celular Tumoral , Transdução de Sinais , MicroRNAs/genética , Proliferação de Células/genética , Regulação Neoplásica da Expressão Gênica , Movimento Celular/genética , Fatores de Processamento de Serina-Arginina/genética
20.
Commun Chem ; 6(1): 105, 2023 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-37258698

RESUMO

Although the electrochemiluminescence (ECL) of metal nanoclusters has been reported, revealing the correlation between structure and ECL at an atomic level is highly challenging. Here, we reported the impact of the metal core of Au20(SAdm)12(CHT)4 (Au20-AC for short; SAdm = 1-adamantanethiolate; CHT= cyclohexanethiol) and its isomer Au20(TBBT)16 (TBBT = 4-tert-butylthiophenol) on their solution-state and solid-state electrochemiluminescence. In self-annihilation ECL experiments, Au20-AC showed a strong cathodic ECL but a weak anodic ECL, while the ECL signal of Au20(TBBT)16 was weak and barely detectable. Density functional theory (DFT) calculations showed that the Au7 kernel of [Au20-AC]- is metastable, weakening its anodic ECL. Au20-AC in solution-state displayed an intense co-reactant ECL in the near-infrared region, which is 7 times higher than that of standard Ru(bpy)32+. The strongest solid-state ECL emissions of Au20-AC and Au20(TBBT)16 were at 860 and 770 nm, respectively - 15 nm red-shifted for Au20-AC and 20 nm blue-shifted for Au20(TBBT)16, compared to their corresponding solid-state photoluminescence (PL) emissions. This work shows that ECL is significantly affected by the subtle differences of the metal core, and offers a potential basis for sensing and immunoassay platforms based on atomically precise emissive metal nanoclusters.

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