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1.
Front Cell Infect Microbiol ; 14: 1413787, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38836053

RESUMO

Background: Trimethylamine-N-oxide (TMAO) is produced by hepatic flavin-containing monooxygenase 3 (FMO3) from trimethylamine (TMA). High TMAO level is a biomarker of cardiovascular diseases and metabolic disorders, and it also affects periodontitis through interactions with the gastrointestinal microbiome. While recent findings indicate that periodontitis may alter systemic TMAO levels, the specific mechanisms linking these changes and particular oral pathogens require further clarification. Methods: In this study, we established a C57BL/6J male mouse model by orally administering Porphyromonas gingivalis (P. gingivalis, Pg), Fusobacterium nucleatum (F. nucleatum, Fn), Streptococcus mutans (S. mutans, Sm) and PBS was used as a control. We conducted LC-MS/MS analysis to quantify the concentrations of TMAO and its precursors in the plasma and cecal contents of mice. The diversity and composition of the gut microbiome were analyzed using 16S rRNA sequencing. TMAO-related lipid metabolism and enzymes in the intestines and liver were assessed by qPCR and ELISA methods. We further explored the effect of Pg on FMO3 expression and lipid molecules in HepG2 cells by stimulating the cells with Pg-LPS in vitro. Results: The three oral pathogenic bacteria were orally administered to the mice for 5 weeks. The Pg group showed a marked increase in plasma TMAO, betaine, and creatinine levels, whereas no significant differences were observed in the gut TMAO level among the four groups. Further analysis showed similar diversity and composition in the gut microbiomes of both the Pg and Fn groups, which were different from the Sm and control groups. The profiles of TMA-TMAO pathway-related genera and gut enzymes were not significantly different among all groups. The Pg group showed significantly higher liver FMO3 levels and elevated lipid factors (IL-6, TG, TC, and NEFA) in contrast to the other groups. In vitro experiments confirmed that stimulation of HepG2 cells with Pg-LPS upregulated the expression of FMO3 and increased the lipid factors TC, TG, and IL-6. Conclusion: This study conclusively demonstrates that Pg, compared to Fn and Sm, plays a critical role in elevating plasma TMAO levels and significantly influences the TMA-TMAO pathway, primarily by modulating the expression of hepatic FMO3 and directly impacting hepatic lipid metabolism.


Assuntos
Microbioma Gastrointestinal , Metilaminas , Camundongos Endogâmicos C57BL , Oxigenases , Porphyromonas gingivalis , Animais , Masculino , Metilaminas/metabolismo , Metilaminas/sangue , Humanos , Camundongos , Oxigenases/metabolismo , Porphyromonas gingivalis/metabolismo , Fusobacterium nucleatum/metabolismo , Redes e Vias Metabólicas , Células Hep G2 , Metabolismo dos Lipídeos , Modelos Animais de Doenças , Periodontite/microbiologia , Periodontite/metabolismo , Fígado/metabolismo , RNA Ribossômico 16S/genética , Espectrometria de Massas em Tandem , Boca/microbiologia
2.
Eur J Med Chem ; 268: 116229, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38430852

RESUMO

Betel-quid chewing addiction is the leading cause of oral submucous fibrosis and oral cancer, resulting in significant socio-economic burdens. Vaccination may serve as a promising potential remedy to mitigate the abuse and combat accidental overdose of betel nut. Hapten design is the crucial factor to the development of arecoline vaccine that determines the efficacy of a candidate vaccine. Herein, we reported that two kinds of novel arecoline-based haptens were synthesized and conjugated to Bovine Serum Albumin (BSA) to generate immunogens, which generated antibodies with high affinity for arecoline but reduced binding for guvacoline and no affinity for arecaidine or guvacine. Notably, vaccination with Arec-N-BSA, which via the N-position on the tetrahydropyridine ring (tertiary amine group), led to a higher antibody affinity compared to Arec-CONH-BSA, blunted analgesia and attenuated hypothermia for arecoline.


Assuntos
Arecolina , Transtornos Relacionados ao Uso de Substâncias , Arecolina/farmacologia , Arecolina/metabolismo , Vacinas Conjugadas , Areca/metabolismo
3.
J Hazard Mater ; 466: 133625, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38295727

RESUMO

Phthalate esters (PAEs), the most commonly produced and used plasticizers, are widely used in plastic products and agroecosystems, posing risks to agricultural products and human health. However, current research on PAE pollution characteristics in agricultural soils in China is not comprehensive; affecting factors and relationships with microplastics and plasticizer organophosphate esters have not been sufficiently considered. In this study, farmland soil samples were collected with field questionnaires on a national scale across mainland China. The results showed that the detection rate of PAEs was 100% and the Σ16PAEs concentrations were 23.5 - 903 µg/kg. The level of PAEs was highest in the greenhouse, and significantly higher than that in mulched farmland (p < 0.05). The PAE concentration in northwestern China was the lowest among different physical geographic zones. PAEs in farmlands posed a low cancer risk to Chinese people. PAE pollution in farmlands was significantly (p < 0.05) affected by agronomic measures (such as disposal method), environmental factors, and socioeconomic factors. Overall, PAEs were significantly and positively correlated (p < 0.05) with organophosphate esters but not with microplastics. This study aims to provide scientific data for relevant prevention and control policies, as well as actionable recommendations for pollution reduction.


Assuntos
Dietilexilftalato , Microplásticos , Ácidos Ftálicos , Plastificantes , Poluentes do Solo , China , Dibutilftalato , Ésteres , Organofosfatos , Plastificantes/análise , Plásticos , Solo , Poluentes do Solo/análise , Fazendas
4.
BMC Cancer ; 24(1): 59, 2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-38200424

RESUMO

BACKGROUND: Pseudo-computed tomography (pCT) quality is a crucial issue in magnetic resonance image (MRI)-only brain stereotactic radiotherapy (SRT), so this study systematically evaluated it from the multi-modal radiomics perspective. METHODS: 34 cases (< 30 cm³) were retrospectively included (2021.9-2022.10). For each case, both CT and MRI scans were performed at simulation, and pCT was generated by a convolutional neural network (CNN) from planning MRI. Conformal arc or volumetric modulated arc technique was used to optimize the dose distribution. The SRT dose was compared between pCT and planning CT with dose volume histogram (DVH) metrics and gamma index. Wilcoxon test and Spearman analysis were used to identify key factors associated with dose deviations. Additionally, original image features were extracted for radiomic analysis. Tumor control probability (TCP) and normal tissue complication probability (NTCP) were employed for efficacy evaluation. RESULTS: There was no significant difference between pCT and planning CT except for radiomics. The mean value of Hounsfield unit of the planning CT was slightly higher than that of pCT. The Gadolinium-based agents in planning MRI could increase DVH metrics deviation slightly. The median local gamma passing rates (1%/1 mm) between planning CTs and pCTs (non-contrast) was 92.6% (range 63.5-99.6%). Also, differences were observed in more than 85% of original radiomic features. The mean absolute deviation in TCP was 0.03%, and the NTCP difference was below 0.02%, except for the normal brain, which had a 0.16% difference. In addition, the number of SRT fractions and lesions, and lesion morphology could influence dose deviation. CONCLUSIONS: This is the first multi-modal radiomics analysis of CNN-based pCT from planning MRI for SRT of small brain lesions, covering dosiomics and radiomics. The findings suggest the potential of pCT in SRT plan design and efficacy prediction, but caution needs to be taken for radiomic analysis.


Assuntos
Encéfalo , Radiômica , Humanos , Estudos de Viabilidade , Estudos Retrospectivos , Encéfalo/diagnóstico por imagem , Tomografia Computadorizada por Raios X
5.
IEEE Trans Med Imaging ; 43(3): 980-993, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37851552

RESUMO

Recently, the diffusion model has emerged as a superior generative model that can produce high quality and realistic images. However, for medical image translation, the existing diffusion models are deficient in accurately retaining structural information since the structure details of source domain images are lost during the forward diffusion process and cannot be fully recovered through learned reverse diffusion, while the integrity of anatomical structures is extremely important in medical images. For instance, errors in image translation may distort, shift, or even remove structures and tumors, leading to incorrect diagnosis and inadequate treatments. Training and conditioning diffusion models using paired source and target images with matching anatomy can help. However, such paired data are very difficult and costly to obtain, and may also reduce the robustness of the developed model to out-of-distribution testing data. We propose a frequency-guided diffusion model (FGDM) that employs frequency-domain filters to guide the diffusion model for structure-preserving image translation. Based on its design, FGDM allows zero-shot learning, as it can be trained solely on the data from the target domain, and used directly for source-to-target domain translation without any exposure to the source-domain data during training. We evaluated it on three cone-beam CT (CBCT)-to-CT translation tasks for different anatomical sites, and a cross-institutional MR imaging translation task. FGDM outperformed the state-of-the-art methods (GAN-based, VAE-based, and diffusion-based) in metrics of Fréchet Inception Distance (FID), Peak Signal-to-Noise Ratio (PSNR), and Structural Similarity Index Measure (SSIM), showing its significant advantages in zero-shot medical image translation.


Assuntos
Tomografia Computadorizada de Feixe Cônico , Processamento de Imagem Assistida por Computador , Processamento de Imagem Assistida por Computador/métodos , Tomografia Computadorizada de Feixe Cônico/métodos , Imagens de Fantasmas , Razão Sinal-Ruído , Imageamento por Ressonância Magnética
6.
Small ; 20(19): e2309230, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38112271

RESUMO

Bone infection poses a major clinical challenge that can hinder patient recovery and exacerbate postoperative complications. This study has developed a bioactive composite scaffold through the co-assembly and intrafibrillar mineralization of collagen fibrils and zinc oxide (ZnO) nanowires (IMC/ZnO). The IMC/ZnO exhibits bone-like hierarchical structures and enhances capabilities for osteogenesis, antibacterial activity, and bacteria-infected bone healing. During co-cultivation with human bone marrow mesenchymal stem cells (BMMSCs), the IMC/ZnO improves BMMSC adhesion, proliferation, and osteogenic differentiation even under inflammatory conditions. Moreover, it suppresses the activity of Gram-negative Porphyromonas gingivalis and Gram-positive Streptococcus mutans by releasing zinc ions within the acidic infectious microenvironment. In vivo, the IMC/ZnO enables near-complete healing of infected bone defects within the intricate oral bacterial milieu, which is attributed to IMC/ZnO orchestrating M2 macrophage polarization, and fostering an osteogenic and anti-inflammatory microenvironment. Overall, these findings demonstrate the promise of the bioactive scaffold IMC/ZnO for treating bacteria-infected bone defects.


Assuntos
Regeneração Óssea , Colágeno , Células-Tronco Mesenquimais , Nanofios , Osteogênese , Alicerces Teciduais , Óxido de Zinco , Óxido de Zinco/química , Óxido de Zinco/farmacologia , Nanofios/química , Regeneração Óssea/efeitos dos fármacos , Alicerces Teciduais/química , Humanos , Colágeno/química , Células-Tronco Mesenquimais/citologia , Osteogênese/efeitos dos fármacos , Animais , Porphyromonas gingivalis/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Streptococcus mutans/fisiologia , Streptococcus mutans/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos
7.
Radiat Oncol ; 18(1): 192, 2023 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-37986008

RESUMO

PURPOSE: Highly modulated radiotherapy plans aim to achieve target conformality and spare organs at risk, but the high complexity of the plan may increase the uncertainty of treatment. Thus, patient-specific quality assurance (PSQA) plays a crucial role in ensuring treatment accuracy and providing clinical guidance. This study aims to propose a prediction model based on complexity metrics and patient planning dose for PSQA results. MATERIALS AND METHODS: Planning dose, measurement-based reconstructed dose and plan complexity metrics of the 687 radiotherapy plans of patients treated in our institution were collected for model establishing. Global gamma passing rate (GPR, 3%/2mm,10% threshold) of 90% was used as QA criterion. Neural architecture models based on Swin-transformer were adapted to process 3D dose and incorporate 1D metrics to predict QA results. The dataset was divided into training (447), validation (90), and testing (150) sets. Evaluation of predictions was performed using mean absolute error (MAE) for GPR, planning target volume (PTV) HI and PTV CI, mean absolute percentage error (MAPE) for PTV D95, PTV D2 and PTV Dmean, and the area under the receiver operating characteristic (ROC) curve (AUC) for classification. Furthermore, we also compare the prediction results with other models based on either only 1D or 3D inputs. RESULTS: In this dataset, 72.8% (500/687) plans passed the pretreatment QA under the criterion. On the testing set, our model achieves the highest performance, with the 1D model slightly surpassing the 3D model. The performance results are as follows (combine, 1D, and 3D transformer): The AUCs are 0.92, 0.88 and 0.86 for QA classification. The MAEs of prediction are 0.039, 0.046, and 0.040 for 3D GPR, 0.018, 0.021, and 0.019 for PTV HI, and 0.075, 0.078, and 0.084 for PTV CI. Specifically, for cases with 3D GPRs greater than 90%, the MAE could achieve 0.020 (combine). The MAPE of prediction is 1.23%, 1.52%, and 1.66% for PTV D95, 2.36%, 2.67%, and 2.45% for PTV D2, and 1.46%, 1.70%, and 1.71% for PTV Dmean. CONCLUSION: The model based on 1D complexity metrics and 3D planning dose could predict pretreatment PSQA results with high accuracy and the complexity metrics play a leading role in the model. Furthermore, dose-volume metric deviations of PTV could be predicted and more clinically valuable information could be provided.


Assuntos
Radioterapia de Intensidade Modulada , Humanos , Dosagem Radioterapêutica , Radioterapia de Intensidade Modulada/métodos , Planejamento da Radioterapia Assistida por Computador/métodos , Raios gama
8.
Nat Commun ; 14(1): 6963, 2023 10 31.
Artigo em Inglês | MEDLINE | ID: mdl-37907455

RESUMO

Infected bone defects are a major challenge in orthopedic treatment. Native bone tissue possesses an endogenous electroactive interface that induces stem cell differentiation and inhibits bacterial adhesion and activity. However, traditional bone substitutes have difficulty in reconstructing the electrical environment of bone. In this study, we develop a self-promoted electroactive mineralized scaffold (sp-EMS) that generates weak currents via spontaneous electrochemical reactions to activate voltage-gated Ca2+ channels, enhance adenosine triphosphate-induced actin remodeling, and ultimately achieve osteogenic differentiation of mesenchymal stem cells by activating the BMP2/Smad5 pathway. Furthermore, we show that the electroactive interface provided by the sp-EMS inhibits bacterial adhesion and activity via electrochemical products and concomitantly generated reactive oxygen species. We find that the osteogenic and antibacterial dual functions of the sp-EMS depend on its self-promoting electrical stimulation. We demonstrate that in vivo, the sp-EMS achieves complete or nearly complete in situ infected bone healing, from a rat calvarial defect model with single bacterial infection, to a rabbit open alveolar bone defect model and a beagle dog vertical bone defect model with the complex oral bacterial microenvironment. This translational study demonstrates that the electroactive bone graft presents a promising therapeutic platform for complex defect repair.


Assuntos
Osteogênese , Alicerces Teciduais , Ratos , Animais , Coelhos , Cães , Biomimética , Regeneração Óssea , Diferenciação Celular , Bactérias
9.
Medicine (Baltimore) ; 102(34): e34966, 2023 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-37653782

RESUMO

BACKGROUND: Schwannoma is a benign tumor that originates from the cells of nerve sheaths. The occurrence of mobile schwannoma of the lumbar spine is extremely rare, and when clinicians perform spinal explorations in the expected locations, the results are often negative. This report presents a case of mobile schwannoma in the lumbar spine, aiming to remind doctors to consider the possibility of tumor migration during preoperative planning, thereby avoiding secondary harm to the patient. CASE REPORT: A 48-year-old male patient presented with a 2-year history of lower back pain and numbness in both lower extremities, which has progressively worsened over the past 3 months. An Magnetic resonance imaging scan revealed an oval-shaped lesion located in the L2/3 vertebral segment, which migrated to the L3/4 vertebral segment following contrast enhancement. The patient underwent tumor resection surgery, and the diagnosis of schwannoma was confirmed through pathological examination. CONCLUSION: Clinical physicians should increase their understanding of mobile schwannoma of the lumbar spine and utilize imaging techniques to accurately locate the tumor before surgery, in order to avoid unnecessary surgical scope and the risks of additional surgery.


Assuntos
Dor Lombar , Neurilemoma , Masculino , Humanos , Pessoa de Meia-Idade , Vértebras Lombares/diagnóstico por imagem , Vértebras Lombares/cirurgia , Neurilemoma/diagnóstico por imagem , Neurilemoma/cirurgia , Região Lombossacral , Medula Espinal , Dor Lombar/etiologia
10.
Eur J Pharmacol ; 957: 175965, 2023 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-37625682

RESUMO

Atherosclerosis (AS)-associated cardiovascular diseases are predominant causes of morbidity and mortality worldwide. Melatonin, a circadian hormone with anti-inflammatory activity, may be a novel therapeutic intervention for AS. However, the exact mechanism is unclear. This research intended to investigate the mechanism of melatonin in treating AS. Melatonin (20 mg/kg/d) was intraperitoneally administered in a high-fat diet (HFD)-induced AS model using apolipoprotein E-deficient (ApoE-/-) mice for 12 weeks. Immunohistochemical and immunofluorescence analyses, data-independent acquisition (DIA)-based protein profiling, ingenuity pathway analysis (IPA), and western blotting were employed to investigate the therapeutic effects of melatonin in treating HFD-induced AS. An adeno-associated virus (AAV) vector was further used to confirm the antiatherosclerotic mechanism of melatonin. Melatonin treatment markedly attenuated atherosclerotic lesions, induced stable phenotypic sclerotic plaques, inhibited macrophage infiltration, and suppressed the production of proinflammatory cytokines in ApoE-/- mice with HFD-induced AS. Notably, DIA-based quantitative proteomics together with IPA identified S100a9 as a pivotal mediator in the protective effects of melatonin. Moreover, melatonin significantly suppressed HFD-induced S100a9 expression at both the mRNA and protein levels. The overexpression of S100a9 significantly activated the NF-κB signaling pathway and markedly abolished the antagonistic effect of melatonin on HFD-induced vascular inflammation during atherogenesis. Melatonin exerts a significant antiatherogenic effect by inhibiting S100a9/NF-κB signaling pathway-mediated vascular inflammation. Our findings reveal a novel antiatherosclerotic mechanism of melatonin and underlie its potential clinical use in modulating AS with good availability and affordability.


Assuntos
Aterosclerose , Melatonina , Animais , Camundongos , Melatonina/farmacologia , Melatonina/uso terapêutico , NF-kappa B , Aterosclerose/tratamento farmacológico , Apolipoproteínas E/genética , Inflamação/tratamento farmacológico
11.
J Neurointerv Surg ; 2023 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-37586821

RESUMO

BACKGROUND: While statins have been widely used in patients with large-artery atherosclerotic stroke, their effectiveness in patients with cardioembolic large vessel occlusion (CE-LVO) undergoing endovascular treatment (EVT) remains unclear. This study aimed to evaluate whether combining statin therapy with EVT could improve clinical outcomes in patients with acute ischemic stroke caused by CE-LVO in the anterior circulation. METHODS: We performed a retrospective screening on patients with CE-LVO in the anterior circulation who underwent EVT in 27 hospitals across China between 2018 and 2021. The primary outcome measure was functional independence, defined as a 90-day modified Rankin Scale (mRS) score of 0 to 2. Safety outcomes included 90-day mortality and symptomatic intracranial hemorrhage (sICH). RESULTS: A total of 510 patients with CE-LVO in the anterior circulation undergoing EVT were included in this study. Of these, 404 (79.2%) patients received statin treatment (statin group), while 106 (20.8%) did not (non-statin group). Statin treatment was significantly associated with improved functional independence (adjusted OR (aOR) 2.072, 95% CI 1.197 to 3.586, P=0.009). Moreover, statin use was associated with a lower rate of 90-day mortality (aOR 0.343, 95% CI 0.197 to 0.596, P<0.001) and a lower rate of sICH (aOR 0.153, 95% CI 0.072 to 0.325, P<0.001). CONCLUSION: Statin treatment was associated with improved clinical outcomes and reduced risks of mortality and sICH in patients with CE-LVO in the anterior circulation undergoing EVT.

12.
Adv Sci (Weinh) ; 10(25): e2302654, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37381631

RESUMO

Special separation membranes are widely employed for separation and purification purposes under challenging operating conditions due to their low energy consumption, excellent solvent, and corrosion resistance. However, the development of membranes is limited by corrosion-resistant polymer substrates and precise interfacial separation layers. Herein, polyaniline (PANI) is employed to achieve insitu anchoring of multiple interfaces, resulting in the fabrication of polyaniline@graphene oxide/polyether ether ketone (PANI@GO/PEEK) membranes. Insitu growth of PANI achieves the adequate bonding of the PEEK substrate and GO separation interface, which solves the problem of solution processing of PEEK and the instability of GO layers. By bottom-up confined polymerization of aniline, it could control the pore size of the separation layer, correct defects, and anchor among polymer, nano-separation layer, and nano-sheet. The mechanism of membrane construction within the confined domain and micro-nano structure modulation is further explored. The membranes demonstrate exceptional stability realizing over 90% rejection in 2 m HCl, NaOH, and high temperatures. Additionally, -membranes exhibit remarkable durability after 240 days immersion and 100 h long-term operation, which display the methanol flux of 50.2 L m-2 h-1 and 92% rejection of AF (585 g mol-1 ). This method substantially contributes to special separation membranes by offering a novel strategy.

13.
Clin Cancer Res ; 29(17): 3284-3291, 2023 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-37363993

RESUMO

PURPOSE: Elective neck irradiation (ENI) has long been considered mandatory when treating head and neck squamous cell carcinoma (HNSCC) with definitive radiotherapy, but it is associated with significant dose to normal organs-at-risk (OAR). In this prospective phase II study, we investigated the efficacy and tolerability of eliminating ENI and strictly treating involved and suspicious lymph nodes (LN) with intensity-modulated radiotherapy. PATIENTS AND METHODS: Patients with newly diagnosed HNSCC of the oropharynx, larynx, and hypopharynx were eligible for enrollment. Each LN was characterized as involved or suspicious based on radiologic criteria and an in-house artificial intelligence (AI)-based classification model. Gross disease received 70 Gray (Gy) in 35 fractions and suspicious LNs were treated with 66.5 Gy, without ENI. The primary endpoint was solitary elective volume recurrence, with secondary endpoints including patterns-of-failure and patient-reported outcomes. RESULTS: Sixty-seven patients were enrolled, with 18 larynx/hypopharynx and 49 oropharynx cancer. With a median follow-up of 33.4 months, the 2-year risk of solitary elective nodal recurrence was 0%. Gastrostomy tubes were placed in 14 (21%), with median removal after 2.9 months for disease-free patients; no disease-free patient is chronically dependent. Grade I/II dermatitis was seen in 90%/10%. There was no significant decline in composite MD Anderson Dysphagia Index scores after treatment, with means of 89.1 and 92.6 at 12 and 24 months, respectively. CONCLUSIONS: These results suggest that eliminating ENI is oncologically sound for HNSCC, with highly favorable quality-of-life outcomes. Additional prospective studies are needed to support this promising paradigm before implementation in any nontrial setting.


Assuntos
Neoplasias de Cabeça e Pescoço , Radioterapia de Intensidade Modulada , Humanos , Inteligência Artificial , Neoplasias de Cabeça e Pescoço/radioterapia , Estudos Prospectivos , Qualidade de Vida , Radioterapia de Intensidade Modulada/efeitos adversos , Carcinoma de Células Escamosas de Cabeça e Pescoço/radioterapia
14.
J Colloid Interface Sci ; 645: 493-501, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37159991

RESUMO

Improving the performance of proton exchange membranes (PEMs) through the synthesis of sulfonated polymers with elaborate molecular structures has received extensive approval. However, the tedious synthetic process and consequently high costs restrain their possible substitution for Nafion, a classic PEM material. Herein, a series of semi-crystalline sulfonated poly(ether ketone)s with fluorene-based units were prepared via direct copolymerization of commercially available monomers and followed post-sulfonation, namely SPEK-FD-x, where × represents the molar ratio of the fluorene-containing monomer to the employed bisphenol monomers. The entire synthetic pathway was facile without involving hardly accessible materials. Subsequently, various properties of SPEK-FD-x membranes were investigated and further compared with Nafion 117. Due to the formation of the well-defined hydrophilic-hydrophobic microphase separation morphology and the reinforcement of the PEK crystalline regions, the SPEK-FD-x membranes exhibited outstanding proton conductivity, resistance for methanol permeation, as well as dimensional, thermal, oxidative, and mechanical stability. Among them, the overall behavior of the SPEK-FD-25 membrane was comparable to or even greater than that of Nafion 117, most importantly, it also performed decently in both H2/air fuel cells and direct methanol fuel cells. Therefore, with the straightforward synthesis and superior performance, the SPEK-FD-x membranes may serve as a promising alternative to Nafion.

15.
Am J Physiol Lung Cell Mol Physiol ; 324(6): L783-L798, 2023 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-37039367

RESUMO

NR2F2 is expressed in endothelial cells (ECs) and Nr2f2 knockout produces lethal cardiovascular defects. In humans, reduced NR2F2 expression is associated with cardiovascular diseases including congenital heart disease and atherosclerosis. Here, NR2F2 silencing in human primary ECs led to inflammation, endothelial-to-mesenchymal transition (EndMT), proliferation, hypermigration, apoptosis-resistance, and increased production of reactive oxygen species. These changes were associated with STAT and AKT activation along with increased production of DKK1. Co-silencing DKK1 and NR2F2 prevented NR2F2-loss-induced STAT and AKT activation and reversed EndMT. Serum DKK1 concentrations were elevated in patients with pulmonary arterial hypertension (PAH) and DKK1 was secreted by ECs in response to in vitro loss of either BMPR2 or CAV1, which are genetic defects associated with the development of PAH. In human primary ECs, NR2F2 suppressed DKK1, whereas its loss conversely induced DKK1 and disrupted endothelial homeostasis, promoting phenotypic abnormalities associated with pathologic vascular remodeling. Activating NR2F2 or blocking DKK1 may be useful therapeutic targets for treating chronic vascular diseases associated with EC dysfunction.NEW & NOTEWORTHY NR2F2 loss in the endothelial lining of blood vessels is associated with cardiovascular disease. Here, NR2F2-silenced human endothelial cells were inflammatory, proliferative, hypermigratory, and apoptosis-resistant with increased oxidant stress and endothelial-to-mesenchymal transition. DKK1 was induced in NR2F2-silenced endothelial cells, while co-silencing NR2F2 and DKK1 prevented NR2F2-loss-associated abnormalities in endothelial signaling and phenotype. Activating NR2F2 or blocking DKK1 may be useful therapeutic targets for treating vascular diseases associated with endothelial dysfunction.


Assuntos
Hipertensão Arterial Pulmonar , Doenças Vasculares , Humanos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Células Endoteliais/metabolismo , Doenças Vasculares/metabolismo , Hipertensão Arterial Pulmonar/metabolismo , Hipertensão Pulmonar Primária Familiar/metabolismo , Inflamação/patologia , Fator II de Transcrição COUP/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/genética , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo
16.
Phys Med Biol ; 68(9)2023 04 25.
Artigo em Inglês | MEDLINE | ID: mdl-37017082

RESUMO

Objective. Accurate diagnosis of lymph node metastasis (LNM) is critical in treatment management for patients with head and neck cancer. Positron emission tomography and computed tomography are routinely used for identifying LNM status. However, for small or less fluorodeoxyglucose (FDG) avid nodes, there are always uncertainties in LNM diagnosis. We are aiming to develop a reliable prediction model is for identifying LNM.Approach. In this study, a new automated and reliable multi-objective learning model (ARMO) is proposed. In ARMO, a multi-objective model is introduced to obtain balanced sensitivity and specificity. Meanwhile, confidence is calibrated by introducing individual reliability, whilst the model uncertainty is estimated by a newly defined overall reliability in ARMO. In the training stage, a Pareto-optimal model set is generated. Then all the Pareto-optimal models are used, and a reliable fusion strategy that introduces individual reliability is developed for calibrating the confidence of each output. The overall reliability is calculated to estimate the model uncertainty for each test sample.Main results. The experimental results demonstrated that ARMO obtained more promising results, which the area under the curve, accuracy, sensitivity and specificity can achieve 0.97, 0.93, 0.88 and 0.94, respectively. Meanwhile, based on calibrated confidence and overall reliability, clinicians could pay particular attention to highly uncertain predictions.Significance. In this study, we developed a unified model that can achieve balanced prediction, confidence calibration and uncertainty estimation simultaneously. The experimental results demonstrated that ARMO can obtain accurate and reliable prediction performance.


Assuntos
Neoplasias de Cabeça e Pescoço , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Humanos , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Metástase Linfática , Reprodutibilidade dos Testes , Linfonodos/patologia , Neoplasias de Cabeça e Pescoço/patologia , Estudos Retrospectivos
17.
J Neurointerv Surg ; 16(1): 53-60, 2023 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-36944491

RESUMO

BACKGROUND: Predicting mortality in stroke patients using information available before endovascular treatment (EVT) is an essential component for supporting clinical decision-making. Although the mortality rate of acute basilar artery occlusion (ABAO) after EVT has reached 40%, few studies have focused on predicting mortality in these individuals. Thus, we aimed to develop and validate a machine learning-based mortality prediction tool based on preoperative information for ABAO patients receiving EVT. METHODS: The derivation cohort comprised patients from southern provinces of China in the BASILAR registry. The model (POSITIVE: Predicting mOrtality of baSilar artery occlusion patIents Treated wIth EVT) was trained and optimized using a fivefold cross-validation method in which hyperparameters were selected and fine-tuned. This model was retrospectively tested in patients from the northern provinces of China from the BASILAR registry. A prospective test of POSITIVE was performed on consecutive patients from two hospitals between January 2020 and June 2022. RESULTS: Extreme gradient boosting was employed to construct the POSITIVE model, which achieved the best predictive performance among the eight machine learning algorithms and showed excellent discrimination (area under the curve (AUC) 0.83, 95% confidence interval (95% CI) 0.80 to 0.87) and calibration (Hosmer-Lemeshow test, P>0.05) in the development cohort. AUC yielded by the POSITIVE model for the retrospective test was 0.79 (95% CI 0.71 to 0.85), higher than that obtained by traditional models. Prospective comparisons showed that the POSITIVE model achieved the highest AUC (0.82, 95% CI 0.74 to 0.90) among all prediction models. CONCLUSION: We developed a machine learning algorithm and retrospective and prospective testing with multicentric cohorts, which exhibited a solid predictive performance and may act as a convenient reference to guide decision-making for ABAO patients. The POSITIVE model is presented online for user-friendly access.


Assuntos
Algoritmos , Artéria Basilar , Humanos , Estudos Retrospectivos , Área Sob a Curva , Aprendizado de Máquina
18.
J Appl Clin Med Phys ; 24(4): e13918, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36729373

RESUMO

PURPOSE: Ethos CBCT-based adaptive radiotherapy (ART) system can generate an online adaptive plan by re-optimizing the initial reference plan based on the patient anatomy at the treatment. The optimization process is fully automated without any room for human intervention. Due to the change in anatomy, the ART plan can be significantly different from the initial plan in terms of plan parameters such as the aperture shapes and number of monitor units (MUs). In this study, we investigated the feasibility of using calculation-based patient specific QA for ART plans in conjunction with measurement-based and calculation-based QA for initial plans to establish an action level for the online ART patient-specific QA. METHODS: A cohort of 98 cases treated on CBCT-based ART system were collected for this study. We performed measurement-based QA using ArcCheck and calculation-based QA using Mobius for both the initial plan and the ART plan for analysis. For online the ART plan, Mobius calculation was conducted prior to the delivery, while ArcCheck measurement was delivered on the same day after the treatment. We first investigated the modulation factors (MFs) and MU numbers of the initial plans and ART plans, respectively. The γ passing rates of initial and ART plan QA were analyzed. Then action limits were derived for QA calculation and measurement for both initial and online ART plans, respectively, from 30 randomly selected patient cases, and were evaluated using the other 68 patient cases. RESULTS: The difference in MF between initial plan and ART-plan was 12.9% ± 12.7% which demonstrates their significant difference in plan parameters. Based on the patient QA results, pre-treatment calculation and measurement results are generally well aligned with ArcCheck measurement results for online ART plans, illustrating their feasibility as an indicator of failure in online ART QA measurements. Furthermore, using 30 randomly selected patient cases, the γ analysis action limit derived for initial plans and ART plans are 89.6% and 90.4% in ArcCheck QA (2%/2 mm) and are 92.4% and 93.6% in Mobius QA(3%/2 mm), respectively. According to the calculated action limits, the ArcCheck measurements for all the initial and ART plans passed QA successfully while the Mobius calculation action limits flagged seven and four failure cases respectively for initial plans and ART plans, respectively. CONCLUSION: An ART plan can be substantially different from the initial plan, and therefore a separate session of ART plan QA is needed to ensure treatment safety and quality. The pre-treatment QA calculation via Mobius can serve as a reliable indicator of failure in online ART plan QA. However, given that Ethos ART system is still relatively new, ArcCheck measurement of initial plan is still in practice. It may be skipped as we gain more experience and have better understanding of the system.


Assuntos
Radioterapia de Intensidade Modulada , Tomografia Computadorizada de Feixe Cônico Espiral , Humanos , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia de Intensidade Modulada/métodos , Garantia da Qualidade dos Cuidados de Saúde , Dosagem Radioterapêutica
19.
Spectrochim Acta A Mol Biomol Spectrosc ; 294: 122515, 2023 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-36842211

RESUMO

Spermine (Spm) and spermidine (Spmd) are considered as potential biomarker for early diagnosis of human cancer. Herein, a novel acyclic cucurbituril derivative (UL-ACB) was firstly designed and synthesized, which fluoresces at 460 nm after excitation at 365 nm. UL-ACB is rich in oxygen atoms which are capable of forming coordinate bonds with copper (Cu2+) that cause quenching of UL-ACB fluorescence. Moreover, the addition of biological endogenous substances Spm and Spmd can turn on fluorescence of UL-ACB. Interestingly, the probe showed a remarkable detection efficiency for Spm and Spmd in human urine (the detection limits of Spm and Spmd were 0.156 µM and 0.762 µM, and the linear ranges are 0.156 âˆ¼ 43.06 µM and 0.762 âˆ¼ 29.10 µM), which completely covered the early diagnosis of urinary Spm (1 âˆ¼ 10 µM) and urine Spmd (1 âˆ¼ 20 µM) required concentration range in cancer patients. The probe for Spm and Spmd is simple, time-saving and selective, which may provide a new promising strategy for early cancer diagnosis.


Assuntos
Corantes Fluorescentes , Neoplasias , Humanos , Corantes Fluorescentes/química , Espermidina , Espermina , Neoplasias/diagnóstico , Cobre/química , Espectrometria de Fluorescência
20.
J Appl Clin Med Phys ; 24(2): e13813, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36350273

RESUMO

PURPOSE: Describe an early-adopting institution's experience with online adaptive radiation for stereotactic partial breast irradiation. METHODS AND MATERIALS: Retrospective review of 22 women treated between May 2021 and March 2022 with adaptive stereotactic partial breast irradiation. A total of 106 of 110 fractions were evaluated for dosimetric changes in target coverage and organ-at-risk (OAR) dose. Patient set up with stereotactic wooden frame and adapted per fraction. Treatment and planning times were collected prospectively by radiation therapists. RESULTS: Scheduled PTV30 Gy was <95% in 72.1% and <90% in 38.5% of fractions, and both PTV and CTV coverage were improved significantly after adaption, and 83.7% of fractions were delivered as adapted per physician choice. There was no difference in OAR coverage. Average adaptive treatment planning took 15 min and average time-on-couch was 34.4 min. CONCLUSIONS: Adaptive stereotactic breast irradiation resulted in improved target coverage with equivalent dosing to OARs in an efficient and tolerated treatment time. Improved target coverage allowed for decreased PTV margins compared to prior trial protocols that may improve acute and late toxicities.


Assuntos
Órgãos em Risco , Radiocirurgia , Humanos , Feminino , Dosagem Radioterapêutica , Órgãos em Risco/efeitos da radiação , Estudos de Viabilidade , Planejamento da Radioterapia Assistida por Computador/métodos , Radiocirurgia/métodos
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