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1.
BMC Biol ; 22(1): 23, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38287397

RESUMO

BACKGROUND: Glioblastoma (GBM) is more difficult to treat than other intractable adult tumors. The main reason that GBM is so difficult to treat is that it is highly infiltrative. Migrasomes are newly discovered membrane structures observed in migrating cells. Thus, they can be generated from GBM cells that have the ability to migrate along the brain parenchyma. However, the function of migrasomes has not yet been elucidated in GBM cells. RESULTS: Here, we describe the composition and function of migrasomes generated along with GBM cell migration. Proteomic analysis revealed that LC3B-positive autophagosomes were abundant in the migrasomes of GBM cells. An increased number of migrasomes was observed following treatment with chloroquine (CQ) or inhibition of the expression of STX17 and SNAP29, which are involved in autophagosome/lysosome fusion. Furthermore, depletion of ITGA5 or TSPAN4 did not relieve endoplasmic reticulum (ER) stress in cells, resulting in cell death. CONCLUSIONS: Taken together, our study suggests that increasing the number of autophagosomes, through inhibition of autophagosome/lysosome fusion, generates migrasomes that have the capacity to alleviate cellular stress.


Assuntos
Autofagossomos , Glioblastoma , Humanos , Autofagossomos/metabolismo , Glioblastoma/metabolismo , Autofagia , Proteômica , Lisossomos/metabolismo , Estresse do Retículo Endoplasmático
2.
FASEB J ; 35(10): e21906, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34490940

RESUMO

Glioblastoma (GBM) is a refractory disease that has a highly infiltrative characteristic. Over the past decade, GBM perivascular niche (PVN) has been described as a route of dissemination. Here, we investigated that trailed membrane structures, namely retraction fibers (RFs), are formed by perivascular extracellular matrix (ECM) proteins. By using the anatomical GBM database, we validated that the ECM-related genes were highly expressed in the cells within the PVN where fibronectin (FN) induced RF formation. By disrupting candidates of FN-binding integrins, integrin α5ß1 was identified as the main regulator of RF formation. De novo RFs were produced at the trailing edge, and focal adhesions were actively localized in RFs, indicating that adhesive force makes RFs remain at the bottom surface. Furthermore, we observed that GBM cells more frequently migrated along the residual RFs formed by preceding cells in microfluidic channels in comparison to those in the channels without RFs, suggesting that the infiltrative characteristics GBM could be attributed to RFs formed by the preceding cells in concert with chemoattractant cues. Altogether, we demonstrated that shedding membrane structures of GBM cells are maintained by FN-integrin α5ß1 interaction and promoted their motility .


Assuntos
Neoplasias Encefálicas/metabolismo , Movimento Celular , Fibronectinas/metabolismo , Glioblastoma/metabolismo , Proteínas de Neoplasias/metabolismo , Receptores de Vitronectina/metabolismo , Animais , Neoplasias Encefálicas/patologia , Linhagem Celular Tumoral , Matriz Extracelular/metabolismo , Matriz Extracelular/patologia , Feminino , Glioblastoma/patologia , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus
3.
Int J Mol Sci ; 23(17)2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-36077356

RESUMO

Hemp (Cannabis sativa L.) is used for medicinal purposes owing to its anti-inflammatory and antioxidant activities. We evaluated the protective effect of nanovesicles isolated from hemp plant parts (root, seed, hemp sprout, and leaf) in dextran sulfate sodium (DSS)-induced colitis in mice. The particle sizes of root-derived nanovesicles (RNVs), seed-derived nanovesicles (SNVs), hemp sprout-derived nanovesicles (HSNVs), and leaf-derived nanovesicles (LNVs) were within the range of 100-200 nm as measured by nanoparticle tracking analysis. Acute colitis was induced in C57BL/N mice by 5% DSS in water provided for 7 days. RNVs were administered orally once a day, leading to the recovery of both the small intestine and colon lengths. RNVs, SNVs, and HSNVs restored the tight (ZO-1, claudin-4, occludin) and adherent junctions (E-cadherin and α-tubulin) in DSS-induced small intestine and colon injury. Additionally, RNVs markedly reduced NF-κB activation and oxidative stress proteins in DSS-induced small intestine and colon injury. Tight junction protein expression and epithelial cell permeability were elevated in RNV-, SNV-, and HSNV-treated T84 colon cells exposed to 2% DSS. Interestedly, RNVs, SNVs, HSNVs, and LNVs reduced ALT activity and liver regeneration marker proteins in DSS-induced liver injury. These results showed for the first time that hemp-derived nanovesicles (HNVs) exhibited a protective effect on DSS-induced gut leaky and liver injury through the gut-liver axis by inhibiting oxidative stress marker proteins.


Assuntos
Cannabis , Colite , Animais , Colite/induzido quimicamente , Colite/metabolismo , Colo/metabolismo , Sulfato de Dextrana/toxicidade , Modelos Animais de Doenças , Mucosa Intestinal/metabolismo , Fígado/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Sulfatos , Junções Íntimas/metabolismo
4.
Respir Res ; 21(1): 133, 2020 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-32471435

RESUMO

BACKGROUND: Dust exposure has been reported as a risk factor of pulmonary disease, leading to alterations of segmental airways and parenchymal lungs. This study aims to investigate alterations of quantitative computed tomography (QCT)-based airway structural and functional metrics due to cement-dust exposure. METHODS: To reduce confounding factors, subjects with normal spirometry without fibrosis, asthma and pneumonia histories were only selected, and a propensity score matching was applied to match age, sex, height, smoking status, and pack-years. Thus, from a larger data set (N = 609), only 41 cement dust-exposed subjects were compared with 164 non-cement dust-exposed subjects. QCT imaging metrics of airway hydraulic diameter (Dh), wall thickness (WT), and bifurcation angle (θ) were extracted at total lung capacity (TLC) and functional residual capacity (FRC), along with their deformation ratios between TLC and FRC. RESULTS: In TLC scan, dust-exposed subjects showed a decrease of Dh (airway narrowing) especially at lower-lobes (p < 0.05), an increase of WT (wall thickening) at all segmental airways (p < 0.05), and an alteration of θ at most of the central airways (p < 0.001) compared with non-dust-exposed subjects. Furthermore, dust-exposed subjects had smaller deformation ratios of WT at the segmental airways (p < 0.05) and θ at the right main bronchi and left main bronchi (p < 0.01), indicating airway stiffness. CONCLUSIONS: Dust-exposed subjects with normal spirometry demonstrated airway narrowing at lower-lobes, wall thickening at all segmental airways, a different bifurcation angle at central airways, and a loss of airway wall elasticity at lower-lobes. The airway structural alterations may indicate different airway pathophysiology due to cement dusts.


Assuntos
Brônquios/diagnóstico por imagem , Poeira , Exposição Ambiental/efeitos adversos , Doença Pulmonar Obstrutiva Crônica/induzido quimicamente , Doença Pulmonar Obstrutiva Crônica/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Adulto , Idoso , Poeira/análise , Exposição Ambiental/análise , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doença Pulmonar Obstrutiva Crônica/epidemiologia , Testes de Função Respiratória/métodos , Estudos Retrospectivos , Capacidade Pulmonar Total/fisiologia
5.
J Aerosol Sci ; 146: 105581, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32346183

RESUMO

This study numerically investigates the effect of hygroscopicity on transport and deposition of particles in severe asthmatic lungs with distinct airway structures. The study human subjects were selected from two imaging-based severe asthmatic clusters with one characterized by non-constricted airways and the other by constricted airways in the lower left lobe (LLL). We compared the deposition fractions of sodium chloride (NaCl) particles with a range of aerodynamic diameters (1-8 µm) in cluster archetypes under conditions with and without hygroscopic growth. The temperature and water vapor distributions in the airways were simulated with an airway wall boundary condition that accounts for variable temperature and water vapor evaporation at the interface between the lumen and the airway surface liquid layer. On average, the deposition fraction increased by about 6% due to hygroscopic particle growth in the cluster subjects with constricted airways, while it increased by only about 0.5% in those with non-constricted airways. The effect of particle growth was most significant for particles with an initial diameter of 2 µm in the cluster subjects with constricted airways. The effect diminished with increasing particle size, especially for particles with an initial diameter larger than 4 µm. This suggests the necessity to differentiate asthmatic subjects by cluster in engineering the aerosol size for tailored treatment. Specifically, the treatment of severe asthmatic subjects who have constricted airways with inhalation aerosols may need submicron-sized hygroscopic particles to compensate for particle growth, if one targets for delivering to the peripheral region. These results could potentially inform the choice of particle size for inhalational drug delivery in a cluster-specific manner.

6.
Respir Res ; 20(1): 153, 2019 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-31307479

RESUMO

BACKGROUND: Quantitative computed tomographic (QCT) imaging-based metrics enable to quantify smoking induced disease alterations and to identify imaging-based clusters for current smokers. We aimed to derive clinically meaningful sub-groups of former smokers using dimensional reduction and clustering methods to develop a new way of COPD phenotyping. METHODS: An imaging-based cluster analysis was performed for 406 former smokers with a comprehensive set of imaging metrics including 75 imaging-based metrics. They consisted of structural and functional variables at 10 segmental and 5 lobar locations. The structural variables included lung shape, branching angle, airway-circularity, airway-wall-thickness, airway diameter; the functional variables included regional ventilation, emphysema percentage, functional small airway disease percentage, Jacobian (volume change), anisotropic deformation index (directional preference in volume change), and tissue fractions at inspiration and expiration. RESULTS: We derived four distinct imaging-based clusters as possible phenotypes with the sizes of 100, 80, 141, and 85, respectively. Cluster 1 subjects were asymptomatic and showed relatively normal airway structure and lung function except airway wall thickening and moderate emphysema. Cluster 2 subjects populated with obese females showed an increase of tissue fraction at inspiration, minimal emphysema, and the lowest progression rate of emphysema. Cluster 3 subjects populated with older males showed small airway narrowing and a decreased tissue fraction at expiration, both indicating air-trapping. Cluster 4 subjects populated with lean males were likely to be severe COPD subjects showing the highest progression rate of emphysema. CONCLUSIONS: QCT imaging-based metrics for former smokers allow for the derivation of statistically stable clusters associated with unique clinical characteristics. This approach helps better categorization of COPD sub-populations; suggesting possible quantitative structural and functional phenotypes.


Assuntos
Imageamento Tridimensional/métodos , Doença Pulmonar Obstrutiva Crônica/diagnóstico por imagem , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Fumar/fisiopatologia , Tomografia Computadorizada por Raios X/métodos , Idoso , Estudos de Coortes , Estudos Transversais , Feminino , Volume Expiratório Forçado , Humanos , Masculino , Pessoa de Meia-Idade , Avaliação de Resultados em Cuidados de Saúde , Doença Pulmonar Obstrutiva Crônica/epidemiologia , Fumar/epidemiologia
7.
Respir Res ; 19(1): 178, 2018 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-30227877

RESUMO

BACKGROUND: Classification of COPD is usually based on the severity of airflow, which may not sensitively differentiate subpopulations. Using a multiscale imaging-based cluster analysis (MICA), we aim to identify subpopulations for current smokers with COPD. METHODS: Among the SPIROMICS subjects, we analyzed computed tomography images at total lung capacity (TLC) and residual volume (RV) of 284 current smokers. Functional variables were derived from registration of TLC and RV images, e.g. functional small airways disease (fSAD%). Structural variables were assessed at TLC images, e.g. emphysema and airway wall thickness and diameter. We employed an unsupervised method for clustering. RESULTS: Four clusters were identified. Cluster 1 had relatively normal airway structures; Cluster 2 had an increase of fSAD% and wall thickness; Cluster 3 exhibited a further increase of fSAD% but a decrease of wall thickness and airway diameter; Cluster 4 had a significant increase of fSAD% and emphysema. Clinically, Cluster 1 showed normal FEV1/FVC and low exacerbations. Cluster 4 showed relatively low FEV1/FVC and high exacerbations. While Cluster 2 and Cluster 3 showed similar exacerbations, Cluster 2 had the highest BMI among all clusters. CONCLUSIONS: Association of imaging-based clusters with existing clinical metrics suggests the sensitivity of MICA in differentiating subpopulations.


Assuntos
Avaliação de Resultados em Cuidados de Saúde/métodos , Doença Pulmonar Obstrutiva Crônica/diagnóstico por imagem , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Fumantes , Tomografia Computadorizada por Raios X/métodos , Adulto , Idoso , Análise por Conglomerados , Estudos de Coortes , Estudos Transversais , Feminino , Volume Expiratório Forçado/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade
8.
J Biomech Eng ; 140(1)2018 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-29049545

RESUMO

The aim of this study was to investigate and quantify contributions of kinetic energy and viscous dissipation to airway resistance during inspiration and expiration at various flow rates in airway models of different bifurcation angles. We employed symmetric airway models up to the 20th generation with the following five different bifurcation angles at a tracheal flow rate of 20 L/min: 15 deg, 25 deg, 35 deg, 45 deg, and 55 deg. Thus, a total of ten computational fluid dynamics (CFD) simulations for both inspiration and expiration were conducted. Furthermore, we performed additional four simulations with tracheal flow rate values of 10 and 40 L/min for a bifurcation angle of 35 deg to study the effect of flow rate on inspiration and expiration. Using an energy balance equation, we quantified contributions of the pressure drop associated with kinetic energy and viscous dissipation. Kinetic energy was found to be a key variable that explained the differences in airway resistance on inspiration and expiration. The total pressure drop and airway resistance were larger during expiration than inspiration, whereas wall shear stress and viscous dissipation were larger during inspiration than expiration. The dimensional analysis demonstrated that the coefficients of kinetic energy and viscous dissipation were strongly correlated with generation number. In addition, the viscous dissipation coefficient was significantly correlated with bifurcation angle and tracheal flow rate. We performed multiple linear regressions to determine the coefficients of kinetic energy and viscous dissipation, which could be utilized to better estimate the pressure drop in broader ranges of successive bifurcation structures.


Assuntos
Expiração/fisiologia , Inalação/fisiologia , Modelos Anatômicos , Ventilação Pulmonar , Resistência das Vias Respiratórias , Hidrodinâmica , Cinética , Resistência ao Cisalhamento , Estresse Mecânico , Viscosidade
9.
J Allergy Clin Immunol ; 140(3): 690-700.e8, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28143694

RESUMO

BACKGROUND: Imaging variables, including airway diameter, wall thickness, and air trapping, have been found to be important metrics when differentiating patients with severe asthma from those with nonsevere asthma and healthy subjects. OBJECTIVE: The objective of this study was to identify imaging-based clusters and to explore the association of the clusters with existing clinical metrics. METHODS: We performed an imaging-based cluster analysis using quantitative computed tomography-based structural and functional variables extracted from the respective inspiration and expiration scans of 248 asthmatic patients. The imaging-based metrics included a broader set of multiscale variables, such as inspiratory airway dimension, expiratory air trapping, and registration-based lung deformation (inspiration vs expiration). Asthma subgroups derived from a clustering method were associated with subject demographics, questionnaire results, medication history, and biomarker variables. RESULTS: Cluster 1 was composed of younger patients with early-onset nonsevere asthma and reversible airflow obstruction and normal airway structure. Cluster 2 was composed of patients with a mix of patients with nonsevere and severe asthma with marginal inflammation who exhibited airway luminal narrowing without wall thickening. Clusters 3 and 4 were dominated by patients with severe asthma. Cluster 3 patients were obese female patients with reversible airflow obstruction who exhibited airway wall thickening without airway narrowing. Cluster 4 patients were late-onset older male subjects with persistent airflow obstruction who exhibited significant air trapping and reduced regional deformation. Cluster 3 and 4 patients also showed decreased lymphocyte and increased neutrophil counts, respectively. CONCLUSIONS: Four image-based clusters were identified and shown to be correlated with clinical characteristics. Such clustering serves to differentiate asthma subgroups that can be used as a basis for the development of new therapies.


Assuntos
Asma/classificação , Asma/diagnóstico por imagem , Adulto , Asma/patologia , Análise por Conglomerados , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fenótipo , Análise de Componente Principal , Índice de Gravidade de Doença , Tomografia Computadorizada por Raios X , Adulto Jovem
10.
Biochem Biophys Res Commun ; 486(2): 564-570, 2017 04 29.
Artigo em Inglês | MEDLINE | ID: mdl-28327358

RESUMO

Most cancer-related signaling pathways sustain their active or inactive status via genetic mutations or various regulatory mechanisms. Previously, we demonstrated that platelet-derived growth factor (PDGF) activates Notch signaling through nitric oxide (NO)-signaling-driven activation of inhibitor of differentiation 4 (ID4) in glioblastoma (GBM) stem cells (GSCs) and endothelial cells in the vascular niche of GBM, leading to maintenance of GSC traits and GBM progression. Here, we determined that the PDGF-NO-ID4-signaling axis is constantly activated through a positive regulatory circuit. ID4 expression significantly increased PDGF subunit B expression in both in vitro cultures and in vivo tumor xenografts and regulated NO synthase 2 (NOS2) expression and NO production by activating PDGF signaling, as well as that of its receptor (PDGFR). Additionally, ectopic expression of PDGFRα, NOS2, or ID4 activated the PDGF-NO-ID4-signaling circuit and enhanced the self-renewal of GBM cell lines. These results suggested that the positive regulatory circuit associated with PDGF-NO-ID4 signaling plays a pivotal role in regulating the self-renewal and tumor-initiating capacity of GSCs and might provide a promising therapeutic target for GBM.


Assuntos
Neoplasias Encefálicas/genética , Regulação Neoplásica da Expressão Gênica , Glioblastoma/genética , Proteínas Inibidoras de Diferenciação/genética , Proteínas Proto-Oncogênicas c-sis/genética , Transdução de Sinais/genética , Animais , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patologia , Genes Reporter , Glioblastoma/metabolismo , Glioblastoma/patologia , Humanos , Proteínas Inibidoras de Diferenciação/metabolismo , Luciferases/genética , Luciferases/metabolismo , Camundongos Endogâmicos BALB C , Camundongos Nus , Transplante de Neoplasias , Células-Tronco Neoplásicas , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo II/genética , Óxido Nítrico Sintase Tipo II/metabolismo , Proteínas Proto-Oncogênicas c-sis/metabolismo , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/genética , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/metabolismo
11.
Stat Med ; 36(10): 1638-1654, 2017 05 10.
Artigo em Inglês | MEDLINE | ID: mdl-28132419

RESUMO

Methacholine challenge tests are used to measure changes in pulmonary function that indicate symptoms of asthma. In addition to pulmonary function tests, which measure global changes in pulmonary function, computed tomography images taken at full inspiration before and after administration of methacholine provide local air volume changes (hyper-inflation post methacholine) at individual acinar units, indicating local airway hyperresponsiveness. Some of the acini may have extreme air volume changes relative to the global average, indicating hyperresponsiveness, and those extreme values may occur in clusters. We propose a Gaussian mixture model with a spatial smoothness penalty to improve prediction of hyperresponsive locations that occur in spatial clusters. A simulation study provides evidence that the spatial smoothness penalty improves prediction under different data-generating mechanisms. We apply this method to computed tomography data from Seoul National University Hospital on five healthy and ten asthmatic subjects. Copyright © 2017 John Wiley & Sons, Ltd.


Assuntos
Asma/diagnóstico por imagem , Asma/fisiopatologia , Testes de Função Respiratória/estatística & dados numéricos , Adulto , Bioestatística , Hiper-Reatividade Brônquica , Testes de Provocação Brônquica/estatística & dados numéricos , Estudos de Casos e Controles , Simulação por Computador , Feminino , Humanos , Funções Verossimilhança , Masculino , Cloreto de Metacolina , Pessoa de Meia-Idade , Modelos Estatísticos , Distribuição Normal , Tomografia Computadorizada por Raios X/estatística & dados numéricos
12.
Physiol Rep ; 12(1): e15909, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38185478

RESUMO

Asthma with fixed airway obstruction (FAO) is associated with significant morbidity and rapid decline in lung function, making its treatment challenging. Quantitative computed tomography (QCT) along with data postprocessing is a useful tool to obtain detailed information on airway structure, parenchymal function, and computational flow features. In this study, we aim to identify the structural and functional differences between asthma with and without FAO. The FAO group was defined by a ratio of forced expiratory volume in 1 s (FEV1 ) to forced vital capacity (FVC), FEV1 /FVC <0.7. Accordingly, we obtained two sets of QCT images at inspiration and expiration of asthma subjects without (N = 24) and with FAO (N = 12). Structural and functional QCT-derived airway variables were extracted, including normalized hydraulic diameter, normalized airway wall thickness, functional small airway disease, and emphysema percentage. A one-dimensional (1D) computational fluid dynamics (CFD) model considering airway deformation was used to compare the pressure distribution between the two groups. The computational pressures showed strong correlations with the pulmonary function test (PFT)-based metrics. In conclusion, asthma participants with FAO had worse lung functions and higher-pressure drops than those without FAO.


Assuntos
Obstrução das Vias Respiratórias , Asma , Humanos , Estudos de Viabilidade , Hidrodinâmica , Asma/complicações , Asma/diagnóstico por imagem , Obstrução das Vias Respiratórias/diagnóstico por imagem , Tomografia Computadorizada por Raios X
13.
Cell Death Dis ; 15(4): 292, 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38658527

RESUMO

Although bevacizumab (BVZ), a representative drug for anti-angiogenesis therapy (AAT), is used as a first-line treatment for patients with glioblastoma (GBM), its efficacy is notably limited. Whereas several mechanisms have been proposed to explain the acquisition of AAT resistance, the specific underlying mechanisms have yet to be sufficiently ascertained. Here, we established that inhibitor of differentiation 1 (ID1)high/activin Ahigh glioblastoma cell confers resistance to BVZ. The bipotent effect of activin A during its active phase was demonstrated to reduce vasculature dependence in tumorigenesis. In response to a temporary exposure to activin A, this cytokine was found to induce endothelial-to-mesenchymal transition via the Smad3/Slug axis, whereas prolonged exposure led to endothelial apoptosis. ID1 tumors showing resistance to BVZ were established to be characterized by a hypovascular structure, hyperpermeability, and scattered hypoxic regions. Using a GBM mouse model, we demonstrated that AAT resistance can be overcome by administering therapy based on a combination of BVZ and SB431542, a Smad2/3 inhibitor, which contributed to enhancing survival. These findings offer valuable insights that could contribute to the development of new strategies for treating AAT-resistant GBM.


Assuntos
Ativinas , Inibidores da Angiogênese , Bevacizumab , Resistencia a Medicamentos Antineoplásicos , Glioblastoma , Proteína 1 Inibidora de Diferenciação , Glioblastoma/tratamento farmacológico , Glioblastoma/patologia , Glioblastoma/metabolismo , Glioblastoma/irrigação sanguínea , Humanos , Animais , Proteína 1 Inibidora de Diferenciação/metabolismo , Proteína 1 Inibidora de Diferenciação/genética , Camundongos , Inibidores da Angiogênese/farmacologia , Inibidores da Angiogênese/uso terapêutico , Ativinas/metabolismo , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Linhagem Celular Tumoral , Bevacizumab/farmacologia , Bevacizumab/uso terapêutico , Neovascularização Patológica/tratamento farmacológico , Neovascularização Patológica/metabolismo , Neovascularização Patológica/patologia , Camundongos Nus , Apoptose/efeitos dos fármacos
14.
Med Biol Eng Comput ; 2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38777935

RESUMO

Anatomical airway labeling is crucial for precisely identifying airways displaying symptoms such as constriction, increased wall thickness, and modified branching patterns, facilitating the diagnosis and treatment of pulmonary ailments. This study introduces an innovative airway labeling methodology, BranchLabelNet, which accounts for the fractal nature of airways and inherent hierarchical branch nomenclature. In developing this methodology, branch-related parameters, including position vectors, generation levels, branch lengths, areas, perimeters, and more, are extracted from a dataset of 1000 chest computed tomography (CT) images. To effectively manage this intricate branch data, we employ an n-ary tree structure that captures the complicated relationships within the airway tree. Subsequently, we employ a divide-and-group deep learning approach for multi-label classification, streamlining the anatomical airway branch labeling process. Additionally, we address the challenge of class imbalance in the dataset by incorporating the Tomek Links algorithm to maintain model reliability and accuracy. Our proposed airway labeling method provides robust branch designations and achieves an impressive average classification accuracy of 95.94% across fivefold cross-validation. This approach is adaptable for addressing similar complexities in general multi-label classification problems within biomedical systems.

15.
Respir Med ; 225: 107598, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38499273

RESUMO

BACKGROUND: Symptom perception and quality of life (QOL) are important domains for properly managing severe asthma. This study aimed to assess the relationship between airway structural and parenchymal variables measured using chest computed tomography (CT) and subjective symptom perception and QOL in patients with severe asthma enrolled in the Korean Severe Asthma Registry. METHODS: This study used CT-based objective measurements, including airway wall thickness (WT), hydraulic diameter, functional small airway disease (fSAD), and emphysematous lung (Emph), to assess their association with subjective symptom (cough, dyspnea, wheezing, and sputum) perception measured using the visual analog scale, and QOL measured by the Severe Asthma Questionnaire (SAQ). RESULTS: A total of 94 patients with severe asthma were enrolled in this study. The WT and fSAD% were significantly positively associated with cough and dyspnea, respectively. For QOL, WT and Emph% showed significant negative associations with the SAQ. However, there was no significant association between lung function and symptom perception or between lung function and QOL. CONCLUSION: Overall, WT, fSAD%, and Emph% measured using chest CT were associated with subjective symptom perception and QOL in patients with severe asthma. This study provides a basis for clarifying the clinical correlates of imaging-derived metrics and for understanding the mechanisms of respiratory symptom perception.


Assuntos
Asma , Enfisema , Doença Pulmonar Obstrutiva Crônica , Humanos , Qualidade de Vida , Asma/diagnóstico por imagem , Pulmão/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Dispneia/etiologia , Tosse/etiologia , Percepção
16.
Comput Methods Programs Biomed ; 246: 108061, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38341897

RESUMO

BACKGROUND AND OBJECTIVE: A detailed representation of the airway geometry in the respiratory system is critical for predicting precise airflow and pressure behaviors in computed tomography (CT)-image-based computational fluid dynamics (CFD). The CT-image-based geometry often contains artifacts, noise, and discontinuities due to the so-called stair step effect. Hence, an advanced surface smoothing is necessary. The existing smoothing methods based on the Laplacian operator drastically shrink airway geometries, resulting in the loss of information related to smaller branches. This study aims to introduce an unsupervised airway-mesh-smoothing learning (AMSL) method that preserves the original geometry of the three-dimensional (3D) airway for accurate CT-image-based CFD simulations. METHOD: The AMSL method jointly trains two graph convolutional neural networks (GCNNs) defined on airway meshes to filter vertex positions and face normal vectors. In addition, it regularizes a combination of loss functions such as reproducibility, smoothness and consistency of vertex positions, and normal vectors. The AMSL adopts the concept of a deep mesh prior model, and it determines the self-similarity for mesh restoration without using a large dataset for training. Images of the airways of 20 subjects were smoothed by the AMSL method, and among them, the data of two subjects were used for the CFD simulations to assess the effect of airway smoothing on flow properties. RESULTS: In 18 of 20 benchmark problems, the proposed smoothing method delivered better results compared with the conventional or state-of-the-art deep learning methods. Unlike the traditional smoothing, the AMSL successfully constructed 20 smoothed airways with airway diameters that were consistent with the original CT images. Besides, CFD simulations with the airways obtained by the AMSL method showed much smaller pressure drop and wall shear stress than the results obtained by the traditional method. CONCLUSIONS: The airway model constructed by the AMSL method reproduces branch diameters accurately without any shrinkage, especially in the case of smaller airways. The accurate estimation of airway geometry using a smoothing method is critical for estimating flow properties in CFD simulations.


Assuntos
Pulmão , Humanos , Simulação por Computador , Redes Neurais de Computação , Reprodutibilidade dos Testes
17.
Front Physiol ; 14: 1288246, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38074321

RESUMO

Rationale: The increase in the incidence and the diagnostic limitations of pneumoconiosis have emerged as a public health concern. This study aimed to conduct a computed tomography (CT)- based quantitative analysis to understand differences in imaging results of pneumoconiosis according to disease severity. Methods: According to the International Labor Organization (ILO) guidelines, coal workers' pneumoconiosis (CWP) are classified into five categories. CT images were obtained only at full inspiration and were quantitatively evaluated for airway structural variables such as bifurcation angle (θ), hydraulic diameter (Dh), wall thickness (WT), and circularity (Cr). Parenchymal functional variables include abnormal regions (emphysema, ground-glass opacities, consolidation, semi consolidation, and fibrosis) and blood vessel volume. Through the propensity score matching method, the confounding effects were decreased. Results: Category 4 demonstrated a reduced θ in TriLUL, a thicker airway wall in both the Trachea and Bronint compared to Category 0, and a decreased Cr in Bronint. Category 4 presented with higher abnormal regions except for ground-glass opacity and a narrower pulmonary blood vessel volume. A negative correlation was found between abnormal areas with lower Hounsfield units (HU) than the normal lung and the ratio of forced expiratory volume in 1 s/forced vital capacity, with narrowed pulmonary blood vessel volume which is positively correlated with abnormal areas with upper HU than the normal lung. Conclusion: This study provided valuable insight into pneumoconiosis progression through a comparison of quantitative CT images based on severity. Furthermore, as there has been paucity of studies on the pulmonary blood vessel volume of the CWP, in this study, a correlation between reduced pulmonary blood vessel volume and regions with low HU values holds significant importance.

18.
Comput Biol Med ; 154: 106612, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36738711

RESUMO

BACKGROUND: Deformable image registration is crucial for multiple radiation therapy applications. Fast registration of computed tomography (CT) lung images is challenging because of the large and nonlinear deformation between inspiration and expiration. With advancements in deep learning techniques, learning-based registration methods are considered efficient alternatives to traditional methods in terms of accuracy and computational cost. METHOD: In this study, an unsupervised lung registration network (LRN) with cycle-consistent training is proposed to align two acquired CT-derived lung datasets during breath-holds at inspiratory and expiratory levels without utilizing any ground-truth registration results. Generally, the LRN model uses three loss functions: image similarity, regularization, and Jacobian determinant. Here, LRN was trained on the CT datasets of 705 subjects and tested using 10 pairs of public CT DIR-Lab datasets. Furthermore, to evaluate the effectiveness of the registration technique, target registration errors (TREs) of the LRN model were compared with those of the conventional algorithm (sum of squared tissue volume difference; SSTVD) and a state-of-the-art unsupervised registration method (VoxelMorph). RESULTS: The results showed that the LRN with an average TRE of 1.78 ± 1.56 mm outperformed VoxelMorph with an average TRE of 2.43 ± 2.43 mm, which is comparable to that of SSTVD with an average TRE of 1.66 ± 1.49 mm. In addition, estimating the displacement vector field without any folding voxel consumed less than 2 s, demonstrating the superiority of the learning-based method with respect to fiducial marker tracking and the overall soft tissue alignment with a nearly real-time speed. CONCLUSIONS: Therefore, this proposed method shows significant potential for use in time-sensitive pulmonary studies, such as lung motion tracking and image-guided surgery.


Assuntos
Processamento de Imagem Assistida por Computador , Tomografia Computadorizada por Raios X , Humanos , Processamento de Imagem Assistida por Computador/métodos , Redes Neurais de Computação , Tomografia , Pulmão/diagnóstico por imagem , Algoritmos
19.
Biomater Sci ; 11(16): 5490-5501, 2023 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-37367827

RESUMO

Inflammatory bowel disease (IBD) is a chronic recurrent inflammatory disease of the digestive tract that causes pain and weight loss and also increases the risk of colon cancer. Inspired by the benefits of plant-derived nanovesicles and aloe, we herein report aloe-derived nanovesicles, including aloe vera-derived nanovesicles (VNVs), aloe arborescens-derived nanovesicles (ANVs), and aloe saponaria-derived nanovesicles (SNVs) and evaluate their therapeutic potential and molecular mechanisms in a dextran sulfate sodium (DSS)-induced acute experimental colitis mouse model. Aloe-derived nanovesicles not only facilitate markedly reduced DSS-induced acute colonic inflammation, but also enable the restoration of tight junction (TJ) and adherent junction (AJ) proteins to prevent gut permeability in DSS-induced acute colonic injury. These therapeutic effects are ascribed to the anti-inflammatory and anti-oxidant effects of aloe-derived nanovesicles. Therefore, aloe-derived nanovesicles are a safe treatment option for IBD.


Assuntos
Aloe , Colite , Doenças Inflamatórias Intestinais , Camundongos , Animais , Aloe/metabolismo , Proteínas de Junções Íntimas/metabolismo , Colite/induzido quimicamente , Colite/tratamento farmacológico , Inflamação/tratamento farmacológico , Doenças Inflamatórias Intestinais/tratamento farmacológico , Doenças Inflamatórias Intestinais/induzido quimicamente , Modelos Animais de Doenças , Sulfato de Dextrana , Camundongos Endogâmicos C57BL
20.
Oncol Lett ; 24(5): 413, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36245828

RESUMO

Anti-angiogenesis therapy, a promising remedy against tumor progression, is now widely used to treat numerous types of cancer. Since vascular endothelial growth factor (VEGF) is the most vital factor in angiogenesis, most anti-angiogenesis drugs target the VEGF-related pathway. However, in glioblastoma (GBM), the therapeutic strategy involving the inhibition of VEGF signaling is ineffective. The present study demonstrated that the potential angiogenic function of endothelin-1 (EDN1) was upregulated by inhibitor of differentiation 1 (ID1) independent of VEGF during tumor angiogenesis. Anatomic structure transcriptomes of patients with GBM revealed that the expression levels of ID1 and EDN1 were specifically upregulated in the vascular-related region. The aortic ring assay and endothelial sprouting assay demonstrated that EDN1 more potently promoted endothelial sprouting ability than VEGF. The activity of EDN1 was induced by endothelin receptor, which seemed to mediate regulation via positive feedback. Finally, in patients with GBM who did not respond to bevacizumab, a VEGF antagonist, EDN1 expression was higher than that in bevacizumab responders. Collectively, the present study demonstrated that EDN1 is a potent angiogenic factor inducing endothelial sprouting and may be a novel target for inhibiting glioma angiogenesis.

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