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2.
Cell Death Dis ; 15(3): 218, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38490994

RESUMO

Gastric cancer (GC), notorious for its poor prognosis, often advances to peritoneal dissemination, a crucial determinant of detrimental outcomes. This study intricately explores the role of the TGFß-Smad-LIF axis within the tumor microenvironment in propagating peritoneal metastasis, with a specific emphasis on its molecular mechanism in instigating Neutrophil Extracellular Traps (NETs) formation and encouraging GC cellular functions. Through a blend of bioinformatics analyses, utilizing TCGA and GEO databases, and meticulous in vivo and in vitro experiments, LIF was identified as pivotally associated with GC metastasis, notably, enhancing the NETs formation through neutrophil stimulation. Mechanistically, TGF-ß was substantiated to elevate LIF expression via the activation of the Smad2/3 complex, culminating in NETs formation and consequently, propelling peritoneal metastasis of GC. This revelation uncovers a novel potential therapeutic target, promising a new avenue in managing GC and mitigating its metastatic propensities.


Assuntos
Armadilhas Extracelulares , Neoplasias Peritoneais , Neoplasias Gástricas , Fator de Crescimento Transformador beta , Humanos , Armadilhas Extracelulares/metabolismo , Neutrófilos/metabolismo , Neoplasias Peritoneais/genética , Neoplasias Peritoneais/patologia , Neoplasias Gástricas/patologia , Fator de Crescimento Transformador beta/metabolismo , Microambiente Tumoral , Fator Inibidor de Leucemia/metabolismo , Transdução de Sinais
4.
Dig Dis Sci ; 2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38483780

RESUMO

OBJECTIVE: To investigate the safety and prognosis of enbloc or piecemeal removal after enbloc resection of a gastric GIST by comparing the clinical data of endoscopic en block resection and piecemeal removal (EP) and en block resection and complete removal (EC) of gastric GISTs. METHODS: A total of 111 (43 endoscopic piecemeal, and 68 complete removal) patients with gastric GIST's ≥ 2 cm in diameter who underwent endoscopic therapy from January 2016 to June 2020 at the First Affiliated Hospital of Zhengzhou University were retrospectively analyzed. In all cases, it was ensured that the tumor was intact during the resection, however, it was divided into EP group and EC group based on whether the tumor was completely removed or was cut into pieces which were then removed. The patients' recurrence-free survival rate and recurrence-free survival (RFS) were recorded. RESULTS: There was no statistically significant difference in RFS rates between the two groups (P = 0.197). The EP group had relatively high patient age, tumor diameter, risk classification, and operation time. However, there was no statistically significant difference in the number of nuclear fission images, postoperative hospitalization time, postoperative fasting time, complication rate and complication grading between the two groups (P > 0.05). CONCLUSION: Endoscopic piecemeal removal after en block resection of gastric GIST is safe and effective and achieves similar clinical outcomes as complete removal after en block resection.

6.
Nat Commun ; 15(1): 348, 2024 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-38191601

RESUMO

Topology created by quasi-continuous spatial variations of a local polarization direction represents an exotic state of matter, but field-driven manipulation has been hitherto limited to creation and destruction. Here we report that relatively small electric or mechanical fields can drive the non-volatile rotation of polar spirals in discretized microregions of the relaxor ferroelectric polymer poly(vinylidene fluoride-ran-trifluoroethylene). These polar spirals arise from the asymmetric Coulomb interaction between vertically aligned helical polymer chains, and can be rotated in-plane through various angles with robust retention. Given also that our manipulation of topological order can be detected via infrared absorption, our work suggests a new direction for the application of complex materials.

7.
ACS Appl Mater Interfaces ; 16(1): 1074-1081, 2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-38149600

RESUMO

With the trend of device miniaturization, ultrathin ferroelectric films are gaining more and more attention. However, understanding ferroelectricity in this nanoscale context remains a formidable challenge, primarily due to the heightened relevance of surface effects, which often leads to the loss of net polarization. Here, the influence of surface effects on the polarization as a function of thickness in ultrathin BiFeO3 films is investigated using phase-field simulations. The findings reveal a notable increase in ferroelectric polarization with increasing thickness, with a particularly discernible change occurring below the 10 nm threshold. Upon accounting for surface effects, the polarization is marginally lower than the case without such considerations, with the disparity becoming more pronounced at smaller thicknesses. Moreover, the hysteresis loop and butterfly loop of the ultrathin film were simulated, demonstrating that the ferroelectric properties of films remain robust even down to a thickness of 5 nm. Our investigations provide valuable insights into the significance of ferroelectric thin films in device miniaturization.

8.
Mayo Clin Proc ; 98(11): 1660-1669, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37923523

RESUMO

OBJECTIVE: To evaluate whether abdominal compression significantly increased the total enteroscopy rate in single-balloon enteroscopy (SBE). METHODS: Consecutive patients who underwent SBE at 2 hospitals were prospectively included between June 1, 2020, and September 30, 2021. They were randomly divided into an abdominal compression group and a non-abdominal compression group with use of sealed envelopes generated by a computer. Total enteroscopy rates were compared between the groups. RESULTS: The study included 200 patients. The total enteroscopy rates were 73% and 16% in the abdominal compression and non-abdominal compression groups, respectively (relative risk, 13.55; 95% CI, 6.79 to 27.00; P<.001). The total enteroscopy rate was higher in the 70 patients who were identified to have undergone no previous abdominal surgery or small intestinal stenosis than in the 32 patients who had undergone such procedures in the abdominal compression group (84% vs 47%; relative risk, 6.08; 95% CI, 2.36 to 15.67; P<.001). Relevant positive findings were not significantly different between the groups (58% vs 45%; P=.07). Binary logistic regression analysis found abdominal compression to be associated with a better total enteroscopy rate (odds ratio, 16.68; 95% CI, 7.92 to 35.15; P<.001), and the presence of previous abdominal surgery or small intestinal stenosis was associated with difficulty in completing the total enteroscopy procedure (odds ratio, 0.26; 95% CI, 0.12 to 0.58; P<.01). CONCLUSION: Abdominal compression significantly increased the total enteroscopy rate in SBE. Complete total enteroscopy may be challenging in patients with a history of abdominal surgery or small intestinal stenosis.


Assuntos
Enteropatias , Enteroscopia de Balão Único , Humanos , Constrição Patológica , Endoscopia Gastrointestinal/métodos
9.
Molecules ; 28(19)2023 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-37836818

RESUMO

The removal of antibiotics from wastewater to prevent their environmental accumulation is significant for human health and ecosystems. Herein, iron (Fe)-atom-doped anatase TiO2 nanofibers (Fe-TNs) were manufactured for the photocatalytic Fenton-like decomposition of tylosin (TYL) under LED illumination. Compared with the pristine TiO2 nanofibers (TNs), the optimized Fe-TNs exhibited improved visible-light-driven photocatalytic Fenton-like activity with a TYL degradation efficiency of 98.5% within 4 h. The effective TYL degradation could be attributed to the expanded optical light absorption and accelerated separation and migration of photogenerated electrons and holes after the introduction of Fe. The photogenerated electrons were highly conducive to the generation of active SO4•- radicals as they facilitated Fe(III)/Fe(II) cycles, and to oxidizing TYL. Moreover, the holes could be involved in TYL degradation. Thus, a significant enhancement in TYL degradation could be achieved. This research verifies the use of iron-doped anatase nanofibers as an effective method to synthesize novel photocatalytic Fenton-like catalysts through surface engineering for wastewater remediation.

13.
J Pain Res ; 16: 2871-2882, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37638205

RESUMO

Purpose: Mitochondrial dysfunction of chondrocytes has become an area of focus in Knee Osteoarthritis (KOA) in recent years. Activation of mitophagy could promote the survival of chondrocytes and alleviate cartilage degeneration. The aim of this study was to explore whether mitophagy was involved in the cartilage protection of KOA rabbits after electroacupuncture (EA) intervention. Methods: The rabbits were divided into 3 groups, Control group, KOA group, EA group, with 6 rabbits in each group. KOA model rabbits were established by modified Videman's extended immobilization method for 6 weeks and randomly divided into KOA group and EA group. The rabbits in EA group were treated every other day for 3 weeks. The degree of cartilage degeneration was detected by Safranine O-Fast Green staining and immunofluorescence. The morphological changes of chondrocytes mitochondria were detected by transmission electron microscope. ATP concentration in cartilage was measured by ATP Assay Kit. The changes of Pink1-Parkin signal pathway were detected by immunofluorescence, Western blot, and Real-time PCR. Results: The morphology showed that EA could reduce the degeneration of KOA cartilage and increase the distribution of collagen II. We also found that EA could activate mitophagy in KOA rabbit chondrocytes to remove damaged mitochondria and restore mitochondrial homeostasis, which was manifested as increasing the expression of LC3 II/I, promoting the colocalization of TOM20 and LC3B, reducing the accumulation of mitochondrial markers outer mitochondrial membrane 20 (TOM20) and inner mitochondrial membrane 23 (TIM23), and increasing ATP production in chondrocytes. This regulation might be achieved by upregulating the Pink1-Parkin signal pathway. Conclusion: EA may play a role in protecting KOA cartilage by activating mitophagy mediated through Pink1-Parkin pathway.

14.
Zhen Ci Yan Jiu ; 48(7): 658-65, 2023 Jul 25.
Artigo em Chinês | MEDLINE | ID: mdl-37518959

RESUMO

OBJECTIVE: To observe the effect of acupotomy on the expressions of p16Ink4a and p21Waf1/Cip1 in knee osteoarthritis (KOA) rabbits,so as to analyze whether acupotomy can treat KOA by inhibiting the cellular senescence of chondrocytes. METHODS: Twenty-four New Zealand male rabbits were randomly divided into normal, model, acupotomy and electroacupuncture (EA) groups, with 6 rabbits in each group. The KOA model was established by left hindlimb straightening fixation. After modeling, rabbits in the acupotomy group were treated with acupotomy loosening therapy on high stress points around the affected knee joints such as tendons attachment points of vastus medialis, vastus lateralis, rectus femoris, biceps femoris and pes anserine bursa, once a week for 3 weeks. In the EA group, "Xuehai"(SP10), "Liangqiu" (ST34),"Neixiyan" (EX-LE4) and "Waixiyan" (ST35) on the affected hindlimb were selected for EA treatment (3 mA, 2 Hz/100 Hz), 20 min each time, once every other day for 3 weeks. Before and after treatments, the knee Lequesne MG score and passive range of motion (PROM) of the affected knee joint were evaluated. After the treatments, the expressions of p16Ink4a and p21Waf1/Cip1 in the cartilage tissue of the affected knee joint were detected by immunohistochemistry and Western blot respectively. RESULTS: Before and after treatment, compared with the normal group, the Lequesne MG score was significantly increased (P<0.01), the PROM was significantly decreased (P<0.01) in the model group. After treatment, compared with the normal group, the positive expression and protein expression levels of p16Ink4a and p21Waf1/Cip1 were significantly increased (P<0.01) in the model group; compared with the model group, the Lequesne MG score was significantly decreased (P<0.01), the PROM was significantly increased (P<0.01), the positive expression and protein expression levels of p16Ink4a and p21Waf1/Cip1 were significantly decreased (P<0.01,P<0.05) in the acupo-tomy and EA groups; compared with the EA group, the Lequesne MG score was decreased (P<0.05), the PROM was increased (P<0.05), the positive expression and protein expression levels of p16Ink4a and p21Waf1/Cip1 were decreased (P<0.05,P<0.01) in the acupotomy group. CONCLUSION: Acupotomy intervention can down-regulate the expressions of cellular senescence markers p16Ink4a and p21Waf1/Cip1 in chondrocytes, indicating that acupotomy therapy may alleviate cartilage degeneration by inhibiting chondrocyte premature cellular senescence to treat KOA.


Assuntos
Terapia por Acupuntura , Eletroacupuntura , Osteoartrite do Joelho , Coelhos , Masculino , Animais , Osteoartrite do Joelho/genética , Osteoartrite do Joelho/terapia , Inibidor p16 de Quinase Dependente de Ciclina/genética , Cartilagem/metabolismo
15.
Nat Commun ; 14(1): 3941, 2023 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-37402744

RESUMO

Solomon rings, upholding the symbol of wisdom with profound historical roots, were widely used as decorations in ancient architecture and clothing. However, it was only recently discovered that such topological structures can be formed by self-organization in biological/chemical molecules, liquid crystals, etc. Here, we report the observation of polar Solomon rings in a ferroelectric nanocrystal, which consist of two intertwined vortices and are mathematically equivalent to a [Formula: see text] link in topology. By combining piezoresponse force microscopy observations and phase-field simulations, we demonstrate the reversible switching between polar Solomon rings and vertex textures by an electric field. The two types of topological polar textures exhibit distinct absorption of terahertz infrared waves, which can be exploited in infrared displays with a nanoscale resolution. Our study establishes, both experimentally and computationally, the existence and electrical manipulation of polar Solomon rings, a new form of topological polar structures that may provide a simple way for fast, robust, and high-resolution optoelectronic devices.

16.
Eur J Surg Oncol ; 49(10): 106955, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37330349

RESUMO

OBJECTIVE: To investigate the safety, feasibility and prognosis of endoscopic treatment of giant (≥5 cm) gastric gastrointestinal stromal tumors (gastric GISTs). METHODS: Data from patients who underwent surgical resection of nonmetastatic gastric GISTs in our hospital from January 2016 to February 2022 were collected. The patients were divided into an endoscopic group and a laparoscopic group according to the surgical method. The clinical data and tumor recurrence information were compared between the two groups. RESULTS: Eighteen cases were collected in the endoscopic group and sixty-three cases in the laparoscopic group. There were no significant differences in age, gender, tumor diameter, tumor growth site, tumor growth mode, clinical manifestations, risk classification or complication rate between the two groups (P > 0.05). The hospitalization cost, length of postoperative hospital stay and postoperative fasting time of the endoscopic group were less than those of the laparoscopic group, while the operation time was greater than that of the laparoscopic group (P < 0.05). In the endoscopic group, the follow-up was 33.50 ± 19.410 months, and no patients were lost to follow-up. The laparoscopic group was followed up for 59.07 ± 12.964 months, and eleven patients were lost to follow-up. There was no recurrence or metastasis in the two groups during the follow-up. CONCLUSION: Endoscopic resection of gastric GIST with a diameter ≥5 cm is technically feasible. And it not only achieves a short-term prognosis similar to laparoscopic resection but also has the advantages of rapid postoperative recovery and low cost.


Assuntos
Tumores do Estroma Gastrointestinal , Laparoscopia , Neoplasias Gástricas , Humanos , Tumores do Estroma Gastrointestinal/cirurgia , Tumores do Estroma Gastrointestinal/patologia , Resultado do Tratamento , Gastrectomia/métodos , Estudos Retrospectivos , Recidiva Local de Neoplasia/cirurgia , Neoplasias Gástricas/cirurgia , Neoplasias Gástricas/patologia , Laparoscopia/métodos , Tempo de Internação
17.
ACS Appl Mater Interfaces ; 15(18): 22684-22691, 2023 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-37099287

RESUMO

Unidirectional and long-distance liquid transport is critically important to a range of practical applications, e.g., water harvesting, microfluidics, and chemical reactions. Great efforts have been made on liquid manipulation; most of which, however, are limited in the air environment. It is still a great challenge to achieve unidirectional and long-distance oil transport in an aqueous environment. Herein, we have successfully fabricated an underwater superoleophilic two-dimensional surface (USTS) with asymmetric oleophobic barriers to arbitrarily manipulate oil in aqueous medium. The behavior of oil on USTS was carefully investigated, of which the unidirectional spreading capability was originated from the anisotropic spreading resistance resulted from the asymmetric oleophobic barriers. Accordingly, an underwater oil/water separation device has been developed, which can achieve continuous and efficient oil/water separation and further prevent the secondary pollution caused by oil volatilization.

18.
ACS Appl Mater Interfaces ; 14(38): 43690-43700, 2022 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-36112494

RESUMO

Block-copolymer-derived ordered mesoporous carbon (OMC) materials have great potential in many applications, such as adsorption, catalysis, and energy conversions; however, their formation process and the kinetic mechanism remain unclear. Herein, a N-doped OMC (N-OMC) with sp2-bonded C atoms is developed via self-assembly of the polystyrene-block-poly(4-vinyl pyridine) block copolymer. By correlating the external morphologies with the internal chemical states, the formation process can be concluded as follows: (1) pore evolution via polystyrene domain degradation and (2) regularization and graphitization of the residual carbon via the removal of sp3 C atoms. In addition, the thickness of the N-OMC shows a power function relationship with the spin-coating rate, and the N content can be incredibly increased up to 26.34 at. % in an NH3 carbonization atmosphere. With the as-prepared N-OMC as the support for loading of the pseudo-atomic-scale Pt (Pt/N-OMC), a high electrochemical active surface area value of 99.64 m2·g-1 and a half-wave potential (E1/2) of 0.850 VRHE are achieved, showing great potential in developing single-atom electrocatalysts.

19.
Nat Commun ; 13(1): 5116, 2022 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-36045121

RESUMO

Recent realizations of ultrathin freestanding perovskite oxides offer a unique platform to probe novel properties in two-dimensional oxides. Here, we observe a giant flexoelectric response in freestanding BiFeO3 and SrTiO3 in their bent state arising from strain gradients up to 3.5 × 107 m-1, suggesting a promising approach for realizing ultra-large polarizations. Additionally, a substantial change in membrane thickness is discovered in bent freestanding BiFeO3, which implies an unusual bending-expansion/shrinkage effect in the ferroelectric membrane that has never been seen before in crystalline materials. Our theoretical model reveals that this unprecedented flexural deformation within the membrane is attributable to a flexoelectricity-piezoelectricity interplay. The finding unveils intriguing nanoscale electromechanical properties and provides guidance for their practical applications in flexible nanoelectromechanical systems.

20.
Nat Commun ; 13(1): 4332, 2022 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-35882838

RESUMO

Ferroelectric domain wall memories have been proposed as a promising candidate for nonvolatile memories, given their intriguing advantages including low energy consumption and high-density integration. Perovskite oxides possess superior ferroelectric prosperities but perovskite-based domain wall memory integrated on silicon has rarely been reported due to the technical challenges in the sample preparation. Here, we demonstrate a domain wall memory prototype utilizing freestanding BaTiO3 membranes transferred onto silicon. While as-grown BaTiO3 films on (001) SrTiO3 substrate are purely c-axis polarized, we find they exhibit distinct in-plane multidomain structures after released from the substrate and integrated onto silicon due to the collective effects from depolarizing field and strain relaxation. Based on the strong in-plane ferroelectricity, conductive domain walls with reading currents up to nanoampere are observed and can be both created and erased artificially, highlighting the great potential of the integration of perovskite oxides with silicon for ferroelectric domain wall memories.

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