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1.
ACS Appl Mater Interfaces ; 16(7): 9453-9465, 2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38329501

RESUMO

Exploring room-temperature intrinsic magnetism in two-dimensional (2D) materials for nanoscale spintronic devices has garnered significant interest. Achieving a high Curie temperature and substantial spin polarization in 2D ferromagnetic materials remains challenging. Drawing inspiration from the substantial enhancement of the Curie temperature observed in ferromagnetic CrIS monolayers by manipulating the covalent nature of Cr-S bonds, our study systematically delves into the electronic structure and magnetic properties of Janus M2X3Y3 (M = V, Cr, Mn, Fe, and Co; X = Cl, Br, I; Y = S, Se, and Te) monolayers through first-principles calculations. Our findings reveal that 15 kinds of these monolayers exhibit dynamic and thermodynamic stability while displaying diverse electronic and ferromagnetic characteristics. Notably, Mn2I3S3 demonstrates half-metallicity and in-plane magnetic anisotropy, while Cr2I3Se3 exhibits a half-semiconductor and perpendicular magnetic anisotropy. Consequently, Mn2I3S3 transforms from in-plane to perpendicular magnetic anisotropy through strain manipulation. Cr2I3Se3, under strain, transforms from a half-semiconductor to a bipolar magnetic semiconductor. The strong coupling caused by the M-Y bonds makes them have a Curie temperature higher than room temperature. The unique magnetic properties exhibited by the 2D Janus Mn2I3S3 and Cr2I3Se3 magnets hold promise for applications in spintronics. Our study provides a foundational understanding for future experimental explorations in this exciting research area.

2.
Math Biosci Eng ; 20(11): 20213-20244, 2023 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-38052643

RESUMO

Brown planthopper Nilaparvata lugens, which can transmit rice ragged stunt virus, is a serious and damaging pest to rice plants. Rice plants can protect themselves from the associated diseases of N.lugens by either suppressing or replacing N.lugens by releasing N.lugens infected by a special strain of Wolbachia wStri. The long-distance migration habit of N.lugens is one of the important precursors leading up to the large-scale occurrence of N.lugens. To study the effect of migration on the transmission of Wolbachia in N.lugens, a Wolbachia spreading dynamics model with migration of N.lugens between two patches is put forward. The existence and local stability conditions of equilibrium points of the system and its subsystems are obtained. Moreover, the effects of migration on the dynamic properties and the control of N.lugens are analyzed; the results show that the system can exhibit a bistable phenomenon, and the migration can change the stability of equilibrium infected with wStri from stable to unstable. The quantitative control methods for the migration of the insect N.lugens are proposed, which provide a theoretical guidance for future field experiments. Lastly, we use the Markov chain Monte Carlo (MCMC) method to estimate the parameters of the wild N.lugens migration model based on limited observational data; the numerical simulation results show that migration can increase the quantity of N.lugens, which is consistent with the relevant experimental results.


Assuntos
Hemípteros , Oryza , Wolbachia , Animais , Insetos
3.
Phys Chem Chem Phys ; 25(39): 26853-26860, 2023 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-37782473

RESUMO

A large voltage-controlled magnetic anisotropy (VCMA) effect is highly desirable for applications of voltage-torque magnetic random access memory. In this work, the dependence of magnetic anisotropy (MA) on the electric field in a MgO-based heterojunction consisting of a new Heusler alloy, Rh2CoSb, is studied using first-principles calculations. We find that the Rh-terminated MgO/Rh2CoSb heterojunction has a perpendicular MA and a giant VCMA coefficient of 7024 fJ V-1 m-1. Furthermore, the VCMA coefficient shows a characteristic of dependence on the electric-field direction. The origins of these behaviors are elucidated by orbital-resolved MA and second-order perturbation theoretical analysis. As the spin-down states of the in-plane orbital, dxy, are close to the Fermi level, the shift of these states induced by the electric field gives rise to significant changes of magnetic anisotropy energy, which is mainly responsible for the giant VCMA effect.

4.
Sci Rep ; 13(1): 7518, 2023 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-37161037

RESUMO

The canonical correspondence analysis (CCA) is a multivariate direct gradient analysis method performing well in many fields, however, when it comes to approximating the unimodal response of species to an environmental gradient, which still assumes that the relationship between the environment and the weighted species score is linear. In this work, we propose a nonlinear canonical correspondence analysis method (NCCA), which first determines the most appropriate nonlinear explanatory factor through two screenings by correlation and LASSO regression, and successively uses the linear regression method and the improved heuristic optimal quadratic approximation method to fit the chi-square transformation values of the response variables. Thus, our method effectively reflects the nonlinear relationship between the species and the environment factors, and a biplot is employed to visualize the effects of the later on the distribution of species. The results from applying this method over a real dataset show that the NCCA method not only maintains the advantages of the polynomial canonical correspondence analysis (PCCA) proposed by Makarenkov (2002), but also outperforms Makarenkov's method in explaining the variance of response variables.

5.
BMC Oral Health ; 22(1): 642, 2022 12 26.
Artigo em Inglês | MEDLINE | ID: mdl-36567318

RESUMO

OBJECTIVES: The indication for removal of asymptomatic fully impacted third molars is still controversial. In this study, radiological and histological investigation of the dental follicle of asymptomatic impacted mandibular third molars was performed, aiming to provide a reference for clinical prophylactic extraction of these teeth. METHODS: Patients with impacted mandibular third molars were included and the maximum width of the dental follicle around the crown was measured in horizontal, sagittal and coronal sections by cone beam computed tomography. The dental follicles were stained with haematoxylin-eosin, analysed by a pathologist and classified as normal, inflammatory or cystic. A Chi-squared test was used to analyse the association of the incidence of inflammation and cysts with the clinical variables of the impacted mandibular third molars. RESULTS: Thirty-seven samples were normal dental follicles; 52 samples showed inflammatory infiltration with an incidence of 57.14%; 2 samples with a maximum dental follicle width of 2-3 mm were diagnosed as odontogenic cysts, and the incidence was 2.20%. There was no significant difference in the incidence of inflammatory and cystic dental follicles between males and females, or between different age groups (P > 0.05). With an increase of the maximum width of the dental follicle, there was a rise in the incidence and degree of infiltration of chronic nonspecific inflammation. CONCLUSION: Asymptomatic impacted mandibular third molars tend to be extracted, especially for teeth with a 2-3 mm maximum width of the dental follicle on radiological examination.


Assuntos
Dente Serotino , Dente Impactado , Masculino , Feminino , Humanos , Dente Serotino/diagnóstico por imagem , Saco Dentário , Dente Molar/patologia , Mandíbula/diagnóstico por imagem , Mandíbula/patologia , Dente Impactado/diagnóstico por imagem , Dente Impactado/patologia , Inflamação/patologia
6.
Cells ; 11(23)2022 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-36497043

RESUMO

Liver fibrosis is a complicated process that involves different cell types and pathological factors. The excessive accumulation of extracellular matrix (ECM) and the formation of fibrotic scar disrupt the tissue homeostasis of the liver, eventually leading to cirrhosis and even liver failure. Myofibroblasts derived from hepatic stellate cells (HSCs) contribute to the development of liver fibrosis by producing ECM in the area of injuries. It has been reported that the secretion of the neuroendocrine hormone in chronic liver injury is different from a healthy liver. Activated HSCs and cholangiocytes express specific receptors in response to these neuropeptides released from the neuroendocrine system and other neuroendocrine cells. Neuroendocrine hormones and their receptors form a complicated network that regulates hepatic inflammation, which controls the progression of liver fibrosis. This review summarizes neuroendocrine regulation in liver fibrosis from three aspects. The first part describes the mechanisms of liver fibrosis. The second part presents the neuroendocrine sources and neuroendocrine compartments in the liver. The third section discusses the effects of various neuroendocrine factors, such as substance P (SP), melatonin, as well as α-calcitonin gene-related peptide (α-CGRP), on liver fibrosis and the potential therapeutic interventions for liver fibrosis.


Assuntos
Células Estreladas do Fígado , Cirrose Hepática , Humanos , Cirrose Hepática/metabolismo , Células Estreladas do Fígado/metabolismo , Miofibroblastos/metabolismo , Sistemas Neurossecretores/metabolismo
7.
Front Public Health ; 10: 1011391, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36408005

RESUMO

Actively addressing urban heat challenges is an urgent task for numerous cities. Existing studies have primarily developed heat mitigation strategies and analyzed their cooling performance, while the adaptation strategies are far from comprehensive to protect citizens from heat-related illnesses and deaths. To address this research gap, this paper aims to enhance people's adaptation capacity by investigating walkability within fifteen-minute cities (FMC). Taking cognizance of thermal comfort, health, and safety, this paper developed a dynamic attenuation model (DAM) of heat stress, along with heat stress aggravation, continuance, and alleviation. An indicator of remaining tolerant heat discomfort (R t ) was proposed with the integration of the Universal Thermal Climate Index (UTCI) to assess heat-related walkability. Following an empirical study among 128 residents in Mianyang, China, and assessing four levels of heat stress, the maximum tolerant heat discomfort was determined to be 60 min. Furthermore, the DAM was applied to an FMC with 12 neighborhoods in Fucheng, Mianyang, China. The results indicate that for each neighborhood, the street was generally walkable with an R t ranging between 15 and 30 min, after walking for 900 m. A population-based FMC walkability was further determined, finding that the core area of the FMC was favorable for walking with an R t of 45-46 min, and the perpetual areas were also walkable with an R t of 15-30 min. Based on these results, suggestions on the frequency of public services (frequently used, often used, and occasionally used) planning were presented. Overall, this paper provides a theoretical model for analyzing walkability and outlines meaningful implications for planning heat adaptation in resilient, safe, comfortable, and livable FMCs.


Assuntos
Planejamento Ambiental , Termotolerância , Humanos , Cidades , Características de Residência , Caminhada
8.
Opt Express ; 30(13): 24062-24071, 2022 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-36225075

RESUMO

A sensitive DC magnetic field sensor is constructed by measuring the signal-to-noise ratio of an AC-modulated magnetic field at a particular frequency from an optical whispering gallery mode microcapillary resonator. The sensing element consists of an optical whispering gallery mode microcapillary resonator bonded to a magnetostrictive material that enables it to respond to external magnetic fields. A DC magnetic field sensitivity of 0.1703dB/Oe and a linear detection range from 4.8Oe to 65.7Oe are realized under an AC modulation field of 168.1kHz in the unshielded environment at room temperature. To our best knowledge, this sensitivity is about 2.3 times of the maximum sensitivity of other DC magnetic field sensors based on magnetic fluid or magnetostrictive material integrated fiber systems that use the dissipative sensing scheme. Furthermore, the sensor can operate at a stable temperature in the range of [-11∼45]°C, as long as the modulation frequency of the AC-modulation field is adjusted according to the ambient temperature. This sensor provides us with a novel DC magnetic field sensing scheme, which may play a role in industrial fields related to current and position detection in the future.

9.
Phys Chem Chem Phys ; 24(36): 21966-21974, 2022 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-36069390

RESUMO

Large perpendicular magnetic anisotropy (MA) is highly desirable for realizing atomic-scale magnetic data storage which represents the ultimate limit of the density of magnetic recording. In this work, we study the MA of transition metal dimers Co-Os, Co-Co and Os-Os adsorbed on two-dimensional ferroelectric In2Se3 (In2Se3-CoOs, In2Se3-OsCo, In2Se3-CoCo and In2Se3-OsOs) using first-principles calculations. We find that the Co-Os dimer in In2Se3-CoOs has a total magnetic anisotropy energy (MAE) of ∼40 meV. The MAE arising from the Os atom in In2Se3-CoOs is up to ∼60 meV. Such large MAE is attributed to the high spin-orbit coupling constant and the onefold coordination of the Os atom. In addition, perpendicular MA can be enhanced in In2Se3-CoOs and induced in In2Se3-OsCo, In2Se3-CoCo and In2Se3-OsOs by the ferroelectric polarization reversal of In2Se3. We demonstrate that the enlargement of exchange splitting of dxy/dx2-y2 and dxz/dyz orbitals for Os atoms in In2Se3-OsOs, Co atom in In2Se3-CoOs and Os and Co atoms in In2Se3-OsCo is responsible for the increase of MAE; while, for the upper Co atom in In2Se3-CoCo and the Os atom in In2Se3-CoOs, the energy rise of the dz2 orbital owing to the change of the crystal field effect by the reversal of ferroelectric polarization results in the increase of MAE.

10.
ACS Appl Mater Interfaces ; 14(18): 21668-21676, 2022 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-35471960

RESUMO

The current-induced magnetization switching and damping-like field in Pt/(Co/Pt)/PtMn trilayer films prepared with and without an in situ in-plane field of 600 Oe have been studied systematically. In the presence of the in situ field, a small in-plane bias field (HEB) is observed for films with PtMn thickness ≥5 nm, while there is no observable HEB for PtMn thickness ≤3 nm. Nevertheless, a field-free switching of perpendicular magnetization of Co/Pt is observed for all the films with the PtMn thickness of 1-7 nm. On the other hand, without the presence of the in situ field, HEB and field-free switching are not seen. Furthermore, the damping-like fields (HDL) are much enhanced in the presence of the in situ field, and the increasement can be up to 47%. We further revealed that the spin current is mainly from the Pt layer, while the noncollinear spin configuration at the interface caused by the in situ in-plane field may play a role in the HDL enhancement. Micromagnetic simulations indicate that the canting of antiferromagnet PtMn spins plays an important role in the field-free switching. Our findings clarify the source of spin current in the trilayer films and provide an easier approach to field-free switching and HDL enhancement for future low-power spintronic devices.

11.
Front Oncol ; 12: 773601, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35311115

RESUMO

Purpose: This study aimed to determine the expression profiles of long non-coding RNA (lncRNA), microRNA (miRNA), and mRNA in chemotherapy-resistant B-cell acute lymphoblastic leukemia (B-ALL). Methods: LncRNA, miRNA, and mRNA profiles were assessed by RNA-seq in diagnostic bone marrow samples from 6 chemotherapy-resistant and 6 chemotherapy-sensitive B-ALL patients. The lncRNA DUXAP8/miR-29a/PIK3CA signaling network was identified as the most dysregulated in chemoresistant patient samples, and its effect on cellular phenotypes, PI3K-AKT-mTOR signaling, and chemosensitivity of doxorubicin (Dox)-resistant Nalm-6 (N6/ADR), and Dox-resistant 697 (697/ADR) cells were assessed. Furthermore, its synergy with inotuzumab ozogamicin treatment was investigated. Results: 1,338 lncRNAs, 75 miRNAs, and 1620 mRNAs were found to be dysregulated in chemotherapy-resistant B-ALL in comparison to chemotherapy-sensitive B-ALL patient samples. Through bioinformatics analyses and RT-qPCR validation, the lncRNA DUXAP8/miR-29a/PIK3CA network and PI3K-AKT-mTOR signaling were identified as significantly associated with B-ALL chemotherapy resistance. In N6/ADR and 697/ADR cells, LncRNA DUXAP8 overexpression and PIK3CA overexpression induced proliferation and inhibited apoptosis, and their respective knockdowns inhibited proliferation, facilitated apoptosis, and restored Dox chemosensitivity. MiR-29a was shown to affect the lncRNA DUXAP8/PIK3CA network, and luciferase reporter gene assay showed direct binding between lncRNA DUXAP8 and miR-29a, as well as between miR-29a and PIK3CA. Targeting lncRNA DUXAP8/miR-29a/PIK3CA network synergized with inotuzumab ozogamicin's effect on N6/ADR and 697/ADR cells. Conclusion: Targeting the lncRNA DUXAP8/miR-29a/PIK3CA network not only induced an apoptotic effect on Dox-resistant B-ALL and restored Dox chemosensitivity via PI3K-AKT-mTOR signaling but also showed synergism with inotuzumab ozogamicin treatment.

12.
Front Public Health ; 10: 801453, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35284385

RESUMO

As a kind of informal green space more closely related to the built environment, public rooftop gardens (PRGs) are novel green open space and important salutogenic resource for urban residents. It is one of the most easily accessible method for urban residents to be in contact with outdoor or natural elements from the context of high-altitude living. Given its potential health benefits to city dwellers, existing empirical studies are heavily focused on immediate recovery through visually accessing PRGs (through windows), neglecting the possibility of using PRGs physically as a place of interaction. This paper hypothesizes usage patterns will mediate the associations between the environmental characteristics of PRG and users' restoration. This is done through inputting data from 12 typical samples of PRG in Chengdu, China into structural equation model (SEM). Combining the concept of Perceived Sensory Dimensions (PSD) and Perceived Restorativeness Scales (PRS) with the usage patterns of the above samples, this study aims to examine the correlation of environmental characteristics, usage pattern and restoration, in which identify their relative importance in the context of PRGs. Through serials of numerical tests on the model, the study shows that out of the 20 theoretical pathways constructed by the environmental characteristics (x)-usage patterns (m)-restorative effect (y), only 14 forms a significant correlation. In addition, out of all PSDs, social, serene, refuge, space and nature dimensions are induced into restorative effects through four patterns of use: retreat, nature touch, interpersonal interaction and family-bonding activities. The findings also show that social and family-bonding are the most influential independent and mediating variables respectively in achieving restorative effects in the PRG. This study reveals important findings about how usage patterns mediate the association between the PSD and PRS of users. And it also has generated practical implications on how we can design public rooftop gardens from the perspective of restoration, which could potentially be the key to the future survival and development of PRGs in urban environments.


Assuntos
Jardins , Parques Recreativos , China , Análise de Classes Latentes
13.
Cell Cycle ; 21(12): 1280-1293, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35285412

RESUMO

Lymphoma is a common malignant tumor globally. Tumor-derived extracellular vesicles (Evs) participate in genetic information exchange between tumor cells. We investigated the role and mechanism of human Burkitt lymphoma cells Raji-derived Evs (Raji-Evs) in lymphoma cells. Effects of Evs on lymphoma cell proliferation, invasion, autophagy, and apoptosis were assessed using Cell Counting Kit-8 method, Transwell assay, laser confocal microscopy, Western blotting, and flow cytometry. microRNA (miR)-106a expression in lymphoma cells was determined using reverse transcription-quantitative polymerase chain reaction and then downregulated in Raji cells and then Evs were isolated (Evs-in-miR-106a) to evaluate its role in lymphoma cell growth. The binding relationship between miR-106a and Beclin1 was verified using RNA pull-down and dual-luciferase assays. Beclin1 was overexpressed in SU-DHL-4 and Farage cells and SU-DHL-4 cell autophagy and apoptosis were detected. The levels of miR-106a and Beclin1 in SU-DHL-4 cells were detected after adding autophagy inhibitors. The tumorigenicity assay in nude mice was performed to validate the effects of Raji-Evs in vivo. Raji-Evs promoted lymphoma cell proliferation and invasion and increased miR-106a. miR-106a knockdown reversed Evs-promoted lymphoma cell proliferation and invasion. miR-106a carried by Raji-Evs targeted Beclin1 expression. Beclin1 overexpression or miR-106a inhibitor reversed the effects of Evs on lymphoma cell autophagy and apoptosis. Autophagy inhibitors elevated miR-106a expression and lowered Beclin1 expression. Raji-Evs-carried miR-106a inhibited Beclin1-dependent autophagy and apoptosis in lymphoma cells, which were further verified in vivo, together with promoted tumor growth. We proved that Raji-Evs inhibited lymphoma cell autophagy and apoptosis and promoted cell growth via the miR-106a/Beclin1 axis.


Assuntos
Vesículas Extracelulares , Linfoma , MicroRNAs , Animais , Apoptose/genética , Autofagia/genética , Proteína Beclina-1/genética , Proteína Beclina-1/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/genética , Vesículas Extracelulares/metabolismo , Linfoma/genética , Linfoma/metabolismo , Camundongos , Camundongos Nus , MicroRNAs/genética , MicroRNAs/metabolismo
15.
Cells ; 12(1)2022 12 31.
Artigo em Inglês | MEDLINE | ID: mdl-36611966

RESUMO

As a newly identified type of programmed cell death, cuproptosis may have an impact on cancer development, including clear cell renal cell carcinoma (ccRCC). Herein, we first noticed that the expression levels of cuproptosis regulators exhibited a tight correlation with the clinicopathological characteristics of ccRCC. The cuproptosis-sensitive sub-type (CSS), classified via consensus clustering analysis, harbored a higher overall survival rate compared to the cuproptosis-resistant sub-type (CRS), which may have resulted from the differential infiltration of immune cells. FDX1, the cuproptosis master regulator, was experimentally determined as a tumor suppressor in ccRCC cells by suppressing the cell growth and cell invasion of ACHN and OSRC-2 cells in a cuproptosis-dependent and -independent manner. The results from IHC staining also demonstrated that FDX1 expression was negatively correlated with ccRCC tumor initiation and progression. Furthermore, we identified the miR-21-5p/FDX1 axis in ccRCC and experimentally verified that miR-21-5p directly binds the 3'-UTR of FDX1 to mediate its degradation. Consequently, a miR-21-5p inhibitor suppressed the cell growth and cell invasion of ACHN and OSRC-2 cells, which could be compensated by FDX1 knockdown, reinforcing the functional linkage between miR-21-5p and FDX1 in ccRCC. Finally, we evaluated the ccRCC tumor microenvironment under the miR-21-5p/FDX1 axis and noted that this axis was strongly associated with the infiltration of immune cells such as CD4+ T cells, Treg cells, and macrophages, suggesting that this signaling axis may alter microenvironmental components to drive ccRCC progression. Overall, this study constructed the miR-21-5p/FDX1 axis in ccRCC and analyzed its potential impact on the tumor microenvironment, providing valuable insights to improve current ccRCC management.


Assuntos
Apoptose , Carcinoma de Células Renais , Neoplasias Renais , MicroRNAs , Humanos , Regiões 3' não Traduzidas , Carcinoma de Células Renais/metabolismo , Proliferação de Células/genética , Neoplasias Renais/patologia , MicroRNAs/genética , MicroRNAs/metabolismo , Microambiente Tumoral/genética , Cobre
16.
Front Public Health ; 9: 604298, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34408998

RESUMO

Earthquakes inevitably affect the mental health of local residents. In seismically active regions of Southwest China, local rural residents' dilapidated housing with poor seismic performance aggravates the impacts of earthquakes on their mental health. These residents' mental health is difficult to recognize because of the lack of appropriate assessment methods. In addition, rural residents in the area have a low socioeconomic status and cannot access adequate mental treatment. Thus, telemedicine could be an effective approach to assist mental health practice in such areas. However, the lack of telemedicine assessment factors in these areas makes it difficult to complete the correct triage and prioritization of rural residents' mental health quickly and effectively. To provide a foundation for applying telemedicine to assess the risk of mental health problems that rural residents in seismically active regions experience, this paper studied whether the degree of safety of housing can affect mental health. In this study, nine villages near the epicenter of the 2019 6.0-magnitude earthquake in Changning County, China were randomly selected, and 162 valid questionnaires were completed. SPSS statistical software was used to analyze the collected data. First, the satisfaction of rural residents with the degree of safety of housing significantly affected the K6 score and whether they suffered from mental problems. Second, the mental health of rural residents living in reinforced concrete frame structure housing was obviously superior to that of those living in other types of housing. Next, the most significant factor affecting mental health was the degree of wall cracks. Finally, a new approach was developed to assess and prioritize the mental health of rural residents by using degrees of housing safety and smart technology in seismically active regions. The telemedicine assessment approach is expected to be used in the future for mental health evaluation and the large-scale data scoring of rural residents.


Assuntos
Terremotos , Telemedicina , Habitação , Humanos , Saúde Mental , População Rural
17.
Eur J Cancer ; 155: 227-235, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34391055

RESUMO

AIM: The aim of this study is to develop and test radiomics models based on magnetic resonance imaging (MRI) to preoperatively and respectively predict the T stage, perineural invasion, and microvascular invasion of extrahepatic cholangiocarcinoma (eCCA) through a non-invasive approach. METHODS: This research included 101 eCCA patients (29-83 years; 45 females and 56 males) between August 2011 and December 2019. Radiomics features were retrospectively extracted from T1-weighted imaging, T2-weighted imaging, diffusion-weighted imaging, and apparent diffusion coefficient map using MaZda software. The region of interest was manually delineated in the largest section on four MRI images as ground truth while keeping 1-2 mm margin to tumor border, respectively. Pretreatment, dimension reduction method, and classifiers were used to establish radiomics signatures for assessing three pathological characteristics of eCCA. Finally, independent training and testing datasets were used to assess radiomics signature performance based on receiver operating characteristic curve analysis, accuracy, precision, sensitivity, and specificity. RESULTS: This study extracted 1208 radiomics features from four MRI images of each patient. The best performing radiomics signatures for assessing the T stage, perineural invasion, and microvascular invasion were respectively produced by L1_normalization + linear discriminant analysis (LDA) + logistic regression, Box_Cox transformer + LDA + K-nearest neighbor, and L2_normalization + LDA + AdaBoost. The area under the curve values of the radiomics signatures for predicting the training and testing cohorts in each subgroup were respectively 1 and 0.962 (T stage), 1 and 1 (both perineural invasion and microvascular invasion). CONCLUSION: These proposed radiomic models based on MR images had powerful performance and high potential in predicting T stage, perineural, and microvascular invasion of eCCA. REPORTING GUIDELINES/RESEARCH DESIGN: Prognostic study.


Assuntos
Colangiocarcinoma/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Radiometria/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Viabilidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Exercício Pré-Operatório , Estudos Retrospectivos
18.
Int J Oncol ; 58(6)2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33887878

RESUMO

Diffuse large B­cell lymphoma (DLBCL) is the most common and aggressive form of non­Hodgkin's lymphoma. Extracellular vesicles (EVs) derived from cancer cells are known to modify the tumor microenvironment. The aim of the present study was to investigate the role of miR­125b­3p carried by EVs in DLBCL in vitro and in vivo. TNFAIP3 expression in patient lesions was measured and the upstream miR that regulates TNFAIP3 was predicted using the starBase database. EVs were isolated from DLBCL cells and identified. DLBCL cells were transfected with pcDNA to overexpress TNFAIP3 or inhibit miR­125b­5p expression, incubated with EVs, and treated with rituximab to compare cell growth and TNFAIP3/CD20 expression. DLBCL model mice were administered EVs, conditioned medium, and rituximab to observe changes in tumor size, volume, and weight. TNFAIP3 was downregulated in patients with DLBCL and its levels further decreased in patients with drug­resistant DLBCL. Overexpression of TNFAIP3 in DLBCL cells enhanced the inhibitory effect of rituximab and increased CD20 expression. miR­125b­5p targeted TNFAIP3. Inhibition of miR­125b­5p enhanced the inhibitory effect of rituximab in DLBCL cells. The EV­carried miR­125b­5p reduced the sensitivity of DLBCL cells to rituximab, which was averted by overexpression of TNFAIP3. EVs reduced the sensitivity of DLBCL model mice to rituximab via the miR­125b­5p/TNFAIP3 axis. The study findings indicate that the tumor­derived EVs carrying miR­125b­5p can enter DLBCL cells and target TNFAIP3, thus reducing the sensitivity of DLBCL to rituximab, which may provide a novel therapeutic approach for DLBCL.


Assuntos
Resistencia a Medicamentos Antineoplásicos/genética , Linfoma Difuso de Grandes Células B/terapia , MicroRNAs/metabolismo , Rituximab/farmacologia , Proteína 3 Induzida por Fator de Necrose Tumoral alfa/genética , Adulto , Idoso , Animais , Estudos de Casos e Controles , Linhagem Celular Tumoral , Quimioterapia Adjuvante/métodos , Vesículas Extracelulares/metabolismo , Feminino , Humanos , Excisão de Linfonodo , Linfonodos/patologia , Linfonodos/cirurgia , Linfoma Difuso de Grandes Células B/genética , Linfoma Difuso de Grandes Células B/patologia , Masculino , Camundongos , Pessoa de Meia-Idade , Rituximab/uso terapêutico , Microambiente Tumoral/genética , Ensaios Antitumorais Modelo de Xenoenxerto
19.
Can J Infect Dis Med Microbiol ; 2021: 6622092, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33791049

RESUMO

OBJECTIVES: To investigate the effects of cytotoxin-associated gene A- (CagA-) positive Helicobacter pylori on proliferation, invasion, autophagy, and expression of miR-125b-5p in colon cancer cells. METHODS: Colon cancer cells were cocultured with H. pylori (CagA+) to analyze the effects of H. pylori on miR-125b-5p and autophagy. Colon cancer cells infected with H. pylori (CagA+) were mimicked by transfection of CagA plasmid. The effects of CagA on the proliferation, invasion, and autophagy of colon cancer cells were analyzed. Cell counting kit-8 (CCK-8), clone formation, and Transwell assays were used to detect cell viability, proliferation, and invasion ability, respectively. Proteins and miRNAs were detected by western blotting and qPCR, respectively. RESULTS: H. pylori (CagA+) inhibited expression of miR-125b-5p and promoted autophagy in colon cancer cells. MiR-125 b-5p was underexpressed in colon cancer cells after CagA overexpression. CagA promoted colon cancer cell proliferation, invasion, and autophagy. Overexpression of miR-125b-5p inhibited the proliferation, invasion, and autophagy of colon cancer cells and reversed the effects of CagA. CONCLUSION: H. pylori (CagA+) infection may promote the development and invasion of colon cancer by inhibiting miR-125b-5p.

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