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1.
Cancer Imaging ; 24(1): 88, 2024 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-38971790

RESUMO

BACKGROUND: The aim of the study were as below. (1) To investigate the feasibility of intravoxel incoherent motion (IVIM)-based virtual magnetic resonance elastography (vMRE) to provide quantitative estimates of tissue stiffness in pulmonary neoplasms. (2) To verify the diagnostic performance of shifted apparent diffusion coefficient (sADC) and reconstructed virtual stiffness values in distinguishing neoplasm nature. METHODS: This study enrolled 59 patients (37 males, 22 females) with one pulmonary neoplasm who underwent computed tomography-guided percutaneous transthoracic needle biopsy (PTNB) with pathological diagnosis (26 adenocarcinoma, 10 squamous cell carcinoma, 3 small cell carcinoma, 4 tuberculosis and 16 non-specific benign; mean age, 60.81 ± 9.80 years). IVIM was performed on a 3 T magnetic resonance imaging scanner before biopsy. sADC and virtual shear stiffness maps reflecting lesion stiffness were reconstructed. sADC and virtual stiffness values of neoplasm were extracted, and the diagnostic performance of vMRE in distinguishing benign and malignant and detailed pathological type were explored. RESULTS: Compared to benign neoplasms, malignant ones had a significantly lower sADC and a higher virtual stiffness value (P < 0.001). Subsequent subtype analyses showed that the sADC values of adenocarcinoma and squamous cell carcinoma groups were significantly lower than non-specific benign group (P = 0.013 and 0.001, respectively). Additionally, virtual stiffness values of the adenocarcinoma and squamous cell carcinoma subtypes were significantly higher than non-specific benign group (P = 0.008 and 0.001, respectively). However, no significant correlation was found among other subtype groups. CONCLUSIONS: Non-invasive vMRE demonstrated diagnostic efficiency in differentiating the nature of pulmonary neoplasm. vMRE is promising as a new method for clinical diagnosis.


Assuntos
Técnicas de Imagem por Elasticidade , Neoplasias Pulmonares , Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Técnicas de Imagem por Elasticidade/métodos , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/patologia , Idoso , Movimento (Física) , Tomografia Computadorizada por Raios X/métodos , Imageamento por Ressonância Magnética/métodos , Estudos de Viabilidade
2.
Am J Transl Res ; 16(6): 2398-2410, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39006270

RESUMO

OBJECTIVE: To develop a nomogram for predicting axillary lymph node metastasis (ALNM) in patients with invasive breast cancer. METHODS: We included 307 patients with clinicopathologically confirmed invasive breast cancer. The cohort was divided into a training group (n=215) and a validation group (n=92). Ultrasound images were used to extract radiomics features. The least absolute shrinkage and selection operator (LASSO) algorithm helped select pertinent features, from which Radiomics Scores (Radscores) were calculated using the LASSO regression equation. We developed three logistic regression models based on Radscores and 2D image features, and assessed the models' performance in the validation group. A nomogram was created from the best-performing model. RESULTS: In the training set, the area under the curve (AUC) for the Radscore model, 2D feature model, and combined model were 0.76, 0.85, and 0.88, respectively. In the validation set, the AUCs were 0.71, 0.78, and 0.83, respectively. The combined model demonstrated good calibration and promising clinical utility. CONCLUSION: Our ultrasound-based radiomics nomogram can accurately and non-invasively predict ALNM in breast cancer, suggesting potential clinical applications to optimize surgical and medical strategies.

3.
Chemosphere ; 363: 142784, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38971447

RESUMO

Cadmium (Cd) in paddy soil poses significant risks to humans due to its strong biological migration and toxicity. Chinese milk vetch (MV) is commonly used as green manure in the paddy fields of southern China and its potential to decrease the availability of Cd has been identified. Nevertheless, the effects of MV combined with lime materials (lime, L; limestone, LS) on Cd availability, soil properties, enzyme activity and comprehensive benefits are still not fully understood in double-cropping rice system. A field study was conducted to investigate these changes. The results indicated that all treatments notably decreased soil available Cd (Avail-Cd) by 19.3-44.3% and 14.9-43.1% during early and late rice, compared with CK. Moreover, the Cd fractions transformed to more stable forms. Compared to CK, all treatments reduced brown rice Cd content by 34.6-64.2% and 12.7-52.5% during the two periods. Furthermore, the translocation factors root to shoot, as well as shoot to brown rice, decreased. The combination led to improvements in soil properties, soil enzyme activity. Meantime, Cd in iron-manganese plaque (IMP) decreased by 31.9-51.1% and 29.0-42.7% respectively during two periods in amendments treatments. Soil pH and DOC were more important factors for Cd bioavailability than other properties. Additionally, rice Cd uptake was positively correlated with Cd in IMP. Enzyme activity exhibited a negative correlation with soil active Cd. Partial Least Squares Path Model (PLS-PM) indicated that the mitigation of Cd pollution helped to improve soil enzyme activity. Grey correlation analysis (GRA) indicated that MVLS showed the best comprehensive benefits in soil-plant system. Overall, the combination of MV and lime materials could reduce Cd availability, enhance soil properties and enzyme activity. And this could be strengthened by the combination. These findings will provide valuable insights for Cd-contaminated soil remediation.

4.
Eur J Med Chem ; 275: 116624, 2024 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-38925015

RESUMO

With the intensive research on the pathogenesis of Alzheimer's disease (AD), inhibition of HDAC6 appears to be a potential therapeutic approach for AD. In this paper, a series of tetrahydro-ß-carboline derivatives with hydroxamic acid group were fast synthesized. Among all, the most potent 15 selectively inhibited HDAC6 with IC50 of 15.2 nM and markedly increased acetylated alpha-tubulin levels. In cellular assay, 15 showed excellent neurotrophic effect by increasing the expression of GAP43 and Beta-3 tubulin markers. Besides, 15 showed neuroprotective effects in PC12 or SH-SY5Y cells against H2O2 and 6-OHDA injury through activation of Nrf2, catalase and Prx II, and significantly reduced H2O2-induced reactive oxygen species (ROS) production. In vivo, 15 significantly attenuated zebrafish anxiety-like behaviour and memory deficits in a SCOP-induced zebrafish model of AD. To sum up, multifunctional 15 might be a good lead to develop novel tetrahydrocarboline-based agents for the treatment of AD.


Assuntos
Doença de Alzheimer , Carbolinas , Desacetilase 6 de Histona , Inibidores de Histona Desacetilases , Fármacos Neuroprotetores , Peixe-Zebra , Carbolinas/farmacologia , Carbolinas/química , Carbolinas/síntese química , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/metabolismo , Humanos , Animais , Desacetilase 6 de Histona/antagonistas & inibidores , Desacetilase 6 de Histona/metabolismo , Ratos , Inibidores de Histona Desacetilases/farmacologia , Inibidores de Histona Desacetilases/síntese química , Inibidores de Histona Desacetilases/química , Relação Estrutura-Atividade , Fármacos Neuroprotetores/farmacologia , Fármacos Neuroprotetores/síntese química , Fármacos Neuroprotetores/química , Estrutura Molecular , Relação Dose-Resposta a Droga , Células PC12 , Espécies Reativas de Oxigênio/metabolismo
5.
Artigo em Inglês | MEDLINE | ID: mdl-38847932

RESUMO

OBJECTIVE: Gonadotropin-releasing hormone agonists (GnRHa), combined with other auxiliary treatments, can improve pregnancy outcomes in in vitro fertilization-embryo transfer (IVF-ET). This research investigated the effect of acupuncture combined with GnRHa in patients with recurrent implantation failure (RIF) of IVF-ET. METHODS: A total of 164 patients who intended to undergo frozen-thawed embryo transfer after RIF of IVF-ET were selected for experiments and then divided into the control (received conventional hormone replacement therapy (HRT) for endometrial preparation) and study groups (received a combination of acupuncture, GnRHa, and HRT for endometrial preparation) (n = 82). Endometrial thickness (EMT), endometrial morphological classification, submucosal uterine blood flow classification, clinical pregnancy rate, embryo implantation rate, and early abortion rate for each transfer cycle were compared between the two groups. RESULTS: EMT of the study group was higher than that of the control group 1 day before transfer. There were more patients with linear endometrium (A + B type) in the study group on the day of endometrial transformation than in the control group. The number of patients with type I submucosal uterine blood flow in the study group was decreased and the number of patients with type III was increased compared with the control group on the day of endometrial transformation. The clinical pregnancy rate and embryo implantation rate of the study group were higher than those of the control group. CONCLUSION: Acupuncture combined with GnRHa improves the endometrial receptivity of patients with RIF of IVF-ET, thereby increasing clinical pregnancy rates and improving pregnancy outcomes.

6.
Molecules ; 29(11)2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38893574

RESUMO

Tourmaline, a boron-bearing mineral, has been extensively applied as a geothermometer, provenance indicator, and fluid-composition recorder in geological studies. In this paper, the decomposition capability of an HF-HNO3-mannitol mixture for a tourmaline sample was investigated in detail for the first time, and a wet acid digestion method based on the boron-mannitol complex for accurate boron determination in tourmaline by inductively coupled plasma mass spectrometry (ICP-MS) was proposed. With a digestion temperature of 140 °C, tourmaline samples of 25 mg (±0.5 mg) can be completely decomposed by a ternary mixture, which consisted of 0.6 mL of HF, 0.6 mL of HNO3, and 0.7 mL of 2% mannitol (wt.), via a continuous heating treatment of 36 h. Following gentle evaporation at 100 °C, the sample residues were re-dissolved using 2 mL of 40% HNO3 solution (wt.) and diluted to about 2.0 × 105-fold by a two-step method using 2% HNO3 solution (wt.). The boron contents in a batch of parallel tourmaline samples were then determined by ICP-MS, and results showed that the boron concentration levels were in a range of 3.20-3.44% with determination RSDs less than 4.0% (n = 5). It was found that the boron concentrations obtained at the mass of 10B were comparable with results from the measurements at the mass of 11B. This revealed that the usage of 2% mannitol with a quantity as high as 0.7 mL in this developed approach did not exhibit significant effect on the quantification accuracy of boron at the mass of 11B. It was also found that the processes including fluoride-forming prevention and fluoride decomposition deteriorated the boron-reserving efficiency of mannitol for tourmaline, causing the averaged boron contents to vary from 2.25% to 3.57% (n = 5). Furthermore, the stability of the boron-mannitol complex under 185 °C by applying the laboratory high pressure-closed digestion method was evaluated, which showed that there existed a 60.36% loss of boron compared to that under 140 °C by using this proposed approach. For this ternary mixture, the tourmaline decomposing efficiency was found to be weakened prominently using 100 °C as the digestion temperature, and tourmaline powders can be observed even after 72 h of continuous heating with B contents within 1.09-1.23% (n = 5). To assess the accuracy of this developed method, the boron recovery of anhydrous lithium tetraborate was studied. It was found that the boron recoveries were within 96.59-102.12% (RSD < 1%, n = 5), demonstrating the accuracy and reliability of this proposed method, which exhibits advantages of high B preserving efficiency, and giving concentration information of both B and trace elements simultaneously. By applying such a boron-mannitol complex-based wet acid digestion method, the chemical composition of boron and trace elements in three tourmaline samples from different pegmatites were quantified, which provided valuable information to distinguish regional deposits and the associated evolution stages.

7.
J Hazard Mater ; 476: 134959, 2024 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-38925053

RESUMO

Microplastics (MPs) are pervasive environmental contaminants that have infiltrated even the most remote ecosystems. Despite their widespread distribution, the transfer patterns and impacts of MPs in remote lakes remain poorly understood. This study aimed to address the knowledge gap regarding the pathways and consequences of MP pollution in these isolated environments. Focusing on Kyêbxang Co, a remote salt lake in Tibet, this study investigated the transfer patterns, sources and ecological impacts of MPs, providing insights into their mobility and fate in pristine ecosystems. Water, sediment and biota (brine shrimp) samples from Kyêbxang Co, collected during the summer of 2020, were analyzed using µ-Raman spectroscopy to determine MP abundances, polymer types and potential sources. Findings indicated significant MP contamination in all examined media, with concentrations highlighting the role of runoff in transporting MPs to remote locations. The majority of detected MPs were small fragments (<0.5 mm), constituting over 93 %, with polypropylene being the predominant polymer type. The presence of a halocline may slow the descent of MPs, potentially increasing the exposure and ingestion risk to brine shrimp. Despite the currently low ecological risk estimated for MPs, this study underscores the need for long-term monitoring and development of a comprehensive ecological risk assessment model for MPs.

8.
BMJ Open ; 14(6): e081933, 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38866577

RESUMO

INTRODUCTION: Hepatic artery complications (HACs), such as a thrombosis or stenosis, are serious causes of morbidity and mortality after paediatric liver transplantation (LT). This study will investigate the incidence, current management practices and outcomes in paediatric patients with HAC after LT, including early and late complications. METHODS AND ANALYSIS: The HEPatic Artery stenosis and Thrombosis after liver transplantation In Children (HEPATIC) Registry is an international, retrospective, multicentre, observational study. Any paediatric patient diagnosed with HAC and treated for HAC (at age <18 years) after paediatric LT within a 20-year time period will be included. The primary outcomes are graft and patient survivals. The secondary outcomes are technical success of the intervention, primary and secondary patency after HAC intervention, intraprocedural and postprocedural complications, description of current management practices, and incidence of HAC. ETHICS AND DISSEMINATION: All participating sites will obtain local ethical approval and (waiver of) informed consent following the regulations on the conduct of observational clinical studies. The results will be disseminated through scientific presentations at conferences and through publication in peer-reviewed journals. TRIAL REGISTRATION NUMBER: The HEPATIC registry is registered at the ClinicalTrials.gov website; Registry Identifier: NCT05818644.


Assuntos
Artéria Hepática , Transplante de Fígado , Complicações Pós-Operatórias , Sistema de Registros , Trombose , Humanos , Transplante de Fígado/efeitos adversos , Estudos Retrospectivos , Criança , Incidência , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Trombose/etiologia , Trombose/epidemiologia , Adolescente , Pré-Escolar , Feminino , Masculino , Constrição Patológica/etiologia , Lactente , Estudos Multicêntricos como Assunto
9.
Anal Chim Acta ; 1315: 342817, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38879215

RESUMO

Diabetes has become one of the most common endocrine and metabolic diseases threatening human health, which can induce mitochondrial dysfunction and exacerbate the excessive production of reactive oxygen species (ROS). Among them, ONOO- level fluctuation was closely related to diabetes. Hence, it is of great significance to develop a near-infrared fluorescence probe for visualizing ONOO- level fluctuations in diabetes. In this paper, we constructed a fluorescence probe YBL with dicyano-isophorone derivative as fluorophore and diphenyl phosphate as ONOO- response site, which can detect ONOO- with the low detection limit (39.8 nM) and exhibit excellent selectivity and sensitivity. The probe YBL has been applied to monitor intracellular ONOO- level fluctuations. Meanwhile, the image results showed that high sugar promoted the increase of ONOO- level in cells. More important, the probe YBL can be used for imaging in mice, and the results showed that content of ONOO- was increased in diabetic mice. Therefore, the probe YBL provided a tool for understanding diabetes progression by imaging ONOO-.


Assuntos
Diabetes Mellitus Experimental , Corantes Fluorescentes , Corantes Fluorescentes/química , Corantes Fluorescentes/síntese química , Animais , Camundongos , Humanos , Diabetes Mellitus Experimental/induzido quimicamente , Imagem Óptica , Raios Infravermelhos , Limite de Detecção
10.
Anal Methods ; 16(24): 3831-3838, 2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38828794

RESUMO

We designed and prepared probe W-1 for the detection of H2O2. W-1 showed excellent selectivity for H2O2 and was accompanied by colorimetric signal changes. The excellent linear relationship between fluorescence intensity and H2O2 concentration (0-100 µM) provided favorable conditions for its quantitative detection. In addition, the combination of portable test strips with a smartphone platform provided great convenience for on-site visual detection of H2O2. Moreover, W-1 possessed targeting mitochondria property and could be applied to image the exogenous and endogenous H2O2 in cells to distinguish normal cells and cancer cells. Lastly, W-1 was used for monitoring the H2O2 fluctuation of the diabetic process in mice, and the results showed an increase in H2O2 levels in diabetes. Therefore, the probe provided a tool for understanding the pathological and physiological mechanisms of diabetes by imaging H2O2.


Assuntos
Diabetes Mellitus Experimental , Corantes Fluorescentes , Peróxido de Hidrogênio , Mitocôndrias , Peróxido de Hidrogênio/metabolismo , Animais , Mitocôndrias/metabolismo , Corantes Fluorescentes/química , Camundongos , Humanos , Colorimetria/métodos , Imagem Óptica/métodos
11.
Front Pharmacol ; 15: 1389953, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38828457

RESUMO

Cardiovascular disease (CVD) is a serious public health risk, and prevention and treatment efforts are urgently needed. Effective preventive and therapeutic programs for cardiovascular disease are still lacking, as the causes of CVD are varied and may be the result of a multifactorial combination. Mitophagy is a form of cell-selective autophagy, and there is increasing evidence that mitophagy is involved in cardioprotective processes. Recently, many studies have shown that FUN14 domain-containing protein 1 (FUNDC1) levels and phosphorylation status are highly associated with many diseases, including heart disease. Here, we review the structure and functions of FUNDC1 and the path-ways of its mediated mitophagy, and show that mitophagy can be effectively activated by dephosphorylation of Ser13 and Tyr18 sites, phosphorylation of Ser17 site and ubiquitination of Lys119 site in FUNDC1. By effectively activating or inhibiting excessive mitophagy, the quality of mitochondria can be effectively controlled. The main reason is that, on the one hand, improper clearance of mitochondria and accumulation of damaged mitochondria are avoided, and on the other hand, excessive mitophagy causing apoptosis is avoided, both serving to protect the heart. In addition, we explore the possible mechanisms by which FUNDC1-mediated mitophagy is involved in exercise preconditioning (EP) for cardioprotection. Finally, we also point out unresolved issues in FUNDC1 and its mediated mitophagy and give directions where further research may be needed.

12.
Gels ; 10(5)2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38786250

RESUMO

Intervertebral disc degeneration (IVDD) is a worldwide disease that causes low back pain and reduces quality of life. Biotherapeutic strategies based on tissue engineering alternatives, such as intervertebral disc scaffolds, supplemented by drug-targeted therapy have brought new hope for IVDD. In this study, to explore the role and mechanism of MnO2/GelMA composite hydrogels in alleviating IVDD, we prepared composite hydrogels with MnO2 and methacrylate gelatin (GelMA) and characterized them using compression testing and transmission electron microscopy (TEM). Annulus fibrosus cells (AFCs) were cultured in the composite hydrogels to verify biocompatibility by live/dead and cytoskeleton staining. Cell viability assays and a reactive oxygen species (ROS) probe were used to analyze the protective effect of the composite hydrogels under oxidative damage. To explore the mechanism of improving the microenvironment, we detected the expression levels of antioxidant and autophagy-related genes and proteins by qPCR and Western blotting. We found that the MnO2/GelMA composite hydrogels exhibited excellent biocompatibility and a porous structure, which promoted cell proliferation. The addition of MnO2 nanoparticles to GelMA cleared ROS in AFCs and induced the expression of antioxidant and cellular autophagy through the common SIRT1/NRF2 pathway. Therefore, the MnO2/GelMA composite hydrogels, which can improve the disc microenvironment through scavenging intracellular ROS and resisting oxidative damage, have great application prospects in the treatment of IVDD.

13.
Front Neurol ; 15: 1387260, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38711554

RESUMO

Background: Autoimmune diseases have always been one of the difficult diseases of clinical concern. Because of the diversity and complexity of its causative factors, unclear occurrence and development process and difficult treatment, it has become a key disease for researchers to study. And the disease explored in this paper, anti-NMDA encephalitis, belongs to a common type of autoimmune encephalitis. However, the quality of articles and research hotspots in this field are not yet known. Therefore, in this field, we completed a bibliometric and visualization analysis from 2005 to 2023 in order to understand the research hotspots and directions of development in this field. Materials and methods: We searched the SCI-expanded databases using Web of Science's core databases on January 22, 2024 and used tools such as VOS viewer, Cite Space, and R software to visualize and analyze the authors, countries, journals, institutions, and keywords of the articles. Results: A total of 1,161 literatures were retrieved and analyzed in this study. China was the country with the most total publications, and USA and Spain were the most influential countries in the field of anti-NMDA encephalitis. University of Pennsylvania from USA was the institution with the highest number of publications. While Dalmau Josep is the most prolific, influential and contributing author who published one of the most cited articles in Lancet Neurology, which laid the foundation for anti-NMDA encephalitis research, the top three appearances of keyword analysis were: "antibodies", "diagnosis", and "autoimmune encephalitis." Conclusion: Bibliometric analysis shows that the number of studies on anti-NMDA encephalitis is generally increasing year by year, and it is a hot disease pursued by researchers. USA and Spain are leading in the field of anti-NMDA encephalitis, while China should continue to improve the quality of its own research. The suspected causes of anti-NMDA encephalitis other than ovarian teratoma and herpes simplex, the specific clinical manifestations that are not masked by psychiatric symptoms, the diagnostic modalities that are faster and more accurate than antibody tests, and the improvement of treatment modalities by evaluating prognosis of various types of patients are the hotspots for future research.

14.
Health Phys ; 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38814189

RESUMO

ABSTRACT: Objective: To evaluate the effectiveness of a general education course titled "The Basis of Radiation Protection" in building and strengthening undergraduate awareness of radiation safety and cultivating innovative individuals with reasonable knowledge structures and strong practical abilities. Methods: All students from 2021 to 2022 enrolled in the core general education course "The Basis of Radiation Protection" at Shandong University of China were invited to participate. A questionnaire survey was conducted to determine changes in the students' basic cognition of radiation safety and scientific protection before and after the course. Results: The survey indicated that the cognitive level of radiation science protection had significantly improved through course completion. The Liszt quantification score range increased from 3.45 to 4.77 to 4.81 to 4.98 (p < 0.001). Further analysis revealed that different professional backgrounds significantly affected students' understanding of radiation safety protection; medical students were superior to electrical engineering students in their knowledge of ionizing radiation before the course (p < 0.001). However, after course completion, the understanding of students from both majors regarding radiation safety had relatively improved, and no significant difference was detected (p > 0.05). Feedback on the course showed that the awareness of "daily radiation protection" had significantly improved (96.8%), pseudoscience and pseudo-information could be correctively identified (93.6%), "nuclear power"-related fears had been dispelled (95.7%), and the concept of "cherishing life" had been effectively established (91.5%). Conclusion: The course effectively improved the awareness of radiation safety, strengthened the knowledge system, and provided a new way to cultivate innovative talent with reasonable knowledge structures.

15.
Nano Lett ; 24(21): 6386-6394, 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38743576

RESUMO

Adhesion ability and interfacial thermal transfer capacity at soft/hard interfaces are of critical importance to a wide variety of applications, ranging from electronic packaging and soft electronics to batteries. However, these two properties are difficult to obtain simultaneously due to their conflicting nature at soft/hard interfaces. Herein, we report a polyurethane/silicon interface with both high adhesion energy (13535 J m-2) and low thermal interfacial resistance (0.89 × 10-6 m2 K W-1) by regulating hydrogen interactions at the interface. This is achieved by introducing a soybean-oil-based epoxy cross-linker, which can destroy the hydrogen bonds in polyurethane networks and meanwhile can promote the formation of hydrogen bonds at the polyurethane/silicon interface. This study provides a comprehensive understanding of enhancing adhesion energy and reducing interfacial thermal resistance at soft/hard interfaces, which offers a promising perspective to tailor interfacial properties in various material systems.

16.
Int J Ophthalmol ; 17(3): 420-434, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38721513

RESUMO

AIM: To explore whether autophagy functions as a cellular adaptation mechanism in lens epithelial cells (LECs) under hyperosmotic stress. METHODS: LECs were treated with hyperosmotic stress at the concentration of 270, 300, 400, 500, or 600 mOsm for 6, 12, 18, 24h in vitro. Polymerase chain reaction (PCR) was employed for the mRNA expression of autophagy-related genes, while Western blotting detected the targeted protein expression. The transfection of stub-RFP-sens-GFP-LC3 autophagy-related double fluorescence lentivirus was conducted to detect the level of autophagy flux. Scanning electron microscopy was used to detect the existence of autolysosome. Short interfering RNA of autophagy-related gene (ATG) 7, transient receptor potential vanilloid (TRPV) 1 overexpression plasmid, related agonists and inhibitors were employed to their influence on autophagy related pathway. Flow cytometry was employed to test the apoptosis and intracellular Ca2+ level. Mitochondrial membrane potential was measured by JC-1 staining. The cell counting kit-8 assay was used to calculate the cellular viability. The wound healing assay was used to evaluate the wound closure rate. GraphPad 6.0 software was utilized to evaluate the data. RESULTS: The hyperosmotic stress activated autophagy in a pressure- and time-dependent manner in LECs. Beclin 1 protein expression and conversion of LC3B II to LC3B I increased, whereas sequestosome-1 (SQSTM1) protein expression decreased. Transient Ca2+ influx was stimulated caused by hyperosmotic stress, levels of mammalian target of rapamycin (mTOR) phosphorylation decreased, and the level of AMP-activated protein kinase (AMPK) phosphorylation increased in the early stage. Based on this evidence, autophagy activation through the Ca2+-dependent AMPK/mTOR pathway might represent an adaptation process in LECs under hyperosmotic stress. Hyperosmotic stress decreased cellular viability and accelerated apoptosis in LECs and cellular migration decreased. Inhibition of autophagy by ATG7 knockdown had similar results. TRPV1 overexpression increased autophagy and might be crucial in the occurrence of autophagy promoted by hyperosmotic stress. CONCLUSION: A combination of hyperosmotic stress and autophagy inhibition may be a promising approach to decrease the number of LECs in the capsular bag and pave the way for improving prevention of posterior capsular opacification and capsular fibrosis.

17.
J Biomech ; 169: 112154, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38768541

RESUMO

Estimating the elasticity of hydrogel phantoms in a cell culture plane is important for understanding the cell behavior in response to various types of mechanical stimuli. Hence, a noncontact tool for measuring the elastic properties of hydrogel phantoms in such three-dimensional cell cultures is required. A well-known method to determine the mechanical properties of hydrogels is the transient wave method. However, due to the multiple reflections of waves from the boundaries, a bigger cell culture plane or multiple directional filters may be required. In this study, we utilized reverberant shear wave elastography, which is based on the autocorrelation principle, to evaluate the shear wave speed in hydrogel samples within a culture dish. Numerical simulations were performed first to confirm the validity of the reverberant elastography method. Subsequently, we used this method to measure the wave speeds in hydrogel phantoms with different concentrations. Shear rheology tests were also performed, and their results were found to be in good agreement with the measured shear wave speeds. The proposed method could be useful for measuring the elasticity of tissues in tissue engineering applications in an inexpensive and noncontact manner.


Assuntos
Técnicas de Imagem por Elasticidade , Hidrogéis , Imagens de Fantasmas , Hidrogéis/química , Técnicas de Imagem por Elasticidade/métodos , Elasticidade , Reologia/métodos
18.
Proc Inst Mech Eng H ; 238(5): 537-549, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38561625

RESUMO

Constructing surface topography with a certain roughness is a widely used, non-toxic, cost-effective and effective method for improving the microenvironment of cells, promoting the proliferation and osteogenic differentiation of mesenchymal stem cells (MSCs), and promoting the osseointegration of grafts and further improving their biocompatibility under clinical environmental conditions. SIRT1 plays an important regulatory role in the osteogenic differentiation of bone marrow-derived MSCs (BM-MSCs). However, it remains unknown whether SIRT1 plays an important regulatory role in the osteogenic differentiation of BM-MSCs with regard to surface morphology. Polydimethylsiloxane (PDMS) with different surface morphologies were prepared using different grits of sandpaper. The value for BMSCs added on different surfaces was detected by cell proliferation assays. RT-qPCR and Western blotting were performed to detect SIRT1 activation and osteogenic differentiation of MSCs. Osteogenesis of MSCs was detected by alkaline phosphatase (ALP) and alizarin red S staining. SIRT1 inhibition experiments were performed to investigate the role of SIRT1 in the osteogenic differentiation of MSCs induced by surface morphology. We found that BM-MSCs have better value and osteogenic differentiation ability on a surface with roughness of PDMS-1000M. SIRT1 showed higher gene and protein expression on a PDMS-1000M surface with a roughness of 13.741 ± 1.388 µm. The promotion of the osteogenic differentiation of MSCs on the PDMS-1000M surface was significantly decreased after inhibiting SIRT1 expression. Our study demonstrated that a surface morphology with certain roughness can activate the SIRT1 pathway of MSCs and promote the osteogenic differentiation of BMSCs via the SIRT1 pathway.


Assuntos
Diferenciação Celular , Dimetilpolisiloxanos , Células-Tronco Mesenquimais , Osteogênese , Transdução de Sinais , Sirtuína 1 , Propriedades de Superfície , Animais , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Dimetilpolisiloxanos/química , Dimetilpolisiloxanos/farmacologia , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , Células-Tronco Mesenquimais/efeitos dos fármacos , Osteogênese/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Sirtuína 1/efeitos dos fármacos , Sirtuína 1/genética , Sirtuína 1/metabolismo
19.
J Mater Chem A Mater ; 12(15): 9184-9199, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38633215

RESUMO

A limiting factor for solid polymer electrolyte (SPE)-based Li-batteries is the functionality of the electrolyte decomposition layer that is spontaneously formed at the Li metal anode. A deeper understanding of this layer will facilitate its improvement. This study investigates three SPEs - polyethylene oxide:lithium tetrafluoroborate (PEO:LiBF4), polyethylene oxide:lithium bis(oxalate)borate (PEO:LiBOB), and polyethylene oxide:lithium difluoro(oxalato)borate (PEO:LiDFOB) - using a combination of electrochemical impedance spectroscopy (EIS), galvanostatic cycling, in situ Li deposition photoelectron spectroscopy (PES), and ab initio molecular dynamics (AIMD) simulations. Through this combination, the cell performance of PEO:LiDFOB can be connected to the initial SPE decomposition at the anode interface. It is found that PEO:LiDFOB had the highest capacity retention, which is correlated to having the least decomposition at the interface. This indicates that the lower SPE decomposition at the interface still creates a more effective decomposition layer, which is capable of preventing further electrolyte decomposition. Moreover, the PES results indicate formation of polyethylene in the SEI in cells based on PEO electrolytes. This is supported by AIMD that shows a polyethylene formation pathway through free-radical polymerization of ethylene.

20.
Front Plant Sci ; 15: 1333816, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38633458

RESUMO

Low temperatures decrease the thidiazuron (TDZ) defoliation efficiency in cotton, while cyclanilide (CYC) combined with TDZ can improve the defoliation efficiency at low temperatures, but the mechanism is unknown. This study analyzed the effect of exogenous TDZ and CYC application on cotton leaf abscissions at low temperatures (daily mean temperature: 15°C) using physiology and transcriptomic analysis. The results showed that compared with the TDZ treatment, TDZ combined with CYC accelerated cotton leaf abscission and increased the defoliation rate at low temperatures. The differentially expressed genes (DEGs) in cotton abscission zones (AZs) were subjected to Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses to compare the enriched GO terms and KEGG pathways between the TDZ treatment and TDZ combined with CYC treatment. TDZ combined with CYC could induce more DEGs in cotton leaf AZs at low temperatures, and these DEGs were related to plant hormone and reactive oxygen species (ROS) pathways. CYC is an auxin transport inhibitor. TDZ combined with CYC not only downregulated more auxin response related genes but also upregulated more ethylene and jasmonic acid (JA) response related genes at low temperatures, and it decreased the indole-3-acetic acid (IAA) content and increased the JA and 1-aminocyclopropane-1-carboxylic acid (ACC) contents, which enhanced cotton defoliation. In addition, compared with the TDZ treatment alone, TDZ combined with CYC upregulated the expression of respiratory burst oxidase homologs (RBOH) genes and the hydrogen peroxide content in cotton AZs at low temperatures, which accelerated cotton defoliation. These results indicated that CYC enhanced the TDZ defoliation efficiency in cotton by adjusting hormone synthesis and response related pathways (including auxin, ethylene, and JA) and ROS production at low temperatures.

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