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1.
J Nanobiotechnology ; 22(1): 299, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38812031

RESUMO

BACKGROUND: Discrepancies in the utilization of reactive oxygen species (ROS) between cancer cells and their normal counterparts constitute a pivotal juncture for the precise treatment of cancer, delineating a noteworthy trajectory in the field of targeted therapies. This phenomenon is particularly conspicuous in the domain of nano-drug precision treatment. Despite substantial strides in employing nanoparticles to disrupt ROS for cancer therapy, current strategies continue to grapple with challenges pertaining to efficacy and specificity. One of the primary hurdles lies in the elevated levels of intracellular glutathione (GSH). Presently, predominant methods to mitigate intracellular GSH involve inhibiting its synthesis or promoting GSH efflux. However, a conspicuous gap remains in the absence of a strategy capable of directly and efficiently clearing GSH. METHODS: We initially elucidated the chemical mechanism underpinning oridonin, a diminutive pharmacological agent demonstrated to perturb reactive oxygen species, through its covalent interaction with glutathione. Subsequently, we employed the incorporation of maleimide-liposomes, renowned for their capacity to disrupt the ROS delivery system, to ameliorate the drug's water solubility and pharmacokinetics, thereby enhancing its ROS-disruptive efficacy. In a pursuit to further refine the targeting for acute myeloid leukemia (AML), we harnessed the maleic imide and thiol reaction mechanism, facilitating the coupling of Toll-like receptor 2 (TLR2) peptides to the liposomes' surface via maleic imide. This strategic approach offers a novel method for the precise removal of GSH, and its enhancement endeavors are directed towards fortifying the precision and efficacy of the drug's impact on AML targets. RESULTS: We demonstrated that this peptide-liposome-small molecule machinery targets AML and consequently induces cell apoptosis both in vitro and in vivo through three disparate mechanisms: (I) Oridonin, as a Michael acceptor molecule, inhibits GSH function through covalent bonding, triggering an initial imbalance of oxidative stress. (II) Maleimide further induces GSH exhaustion, aggravating redox imbalance as a complementary augment with oridonin. (III) Peptide targets TLR2, enhances the directivity and enrichment of oridonin within AML cells. CONCLUSION: The rationally designed nanocomplex provides a ROS drug enhancement and targeted delivery platform, representing a potential solution by disrupting redox balance for AML therapy.


Assuntos
Diterpenos do Tipo Caurano , Glutationa , Leucemia Mieloide Aguda , Lipossomos , Espécies Reativas de Oxigênio , Diterpenos do Tipo Caurano/química , Diterpenos do Tipo Caurano/farmacologia , Glutationa/metabolismo , Glutationa/química , Lipossomos/química , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/metabolismo , Humanos , Espécies Reativas de Oxigênio/metabolismo , Animais , Camundongos , Linhagem Celular Tumoral , Receptor 2 Toll-Like/metabolismo , Antineoplásicos/farmacologia , Antineoplásicos/química , Apoptose/efeitos dos fármacos
2.
Biochem Biophys Res Commun ; 684: 149125, 2023 12 03.
Artigo em Inglês | MEDLINE | ID: mdl-37897912

RESUMO

Ferroptosis, an emerging form of programmed cell death, has garnered substantial attention as a potential target for cancer therapy. However, despite the potential promise, no ferroptosis-related therapies have progressed to clinical trials. Identifying disease types sensitive to ferroptosis and developing specific ferroptosis-targeting drugs are critical focal points in the field of ferroptosis-based treatment. In this study, we conducted a comprehensive database analysis and presented compelling evidence indicating a high expression of GPX4 in patients with acute lymphoblastic leukemia (ALL), significantly correlating with poor prognosis. Notably, elevated GPX4 expression is closely associated with ALL relapse, a major challenge in the treatment of this disease. Building upon these findings, we devised a novel peptide-based Proteolysis Targeting Chimeras (PROTAC) drug targeting GPX4 through computer-aided design. In contrast to existing drugs that target the conjugative enzyme active site, our design focused on a peptide drug targeting the non-active site of GPX4. Furthermore, we strategically selected MDM2, an E3 ligase highly expressed in ALL, for the PROTAC drug design. This deliberate choice amplifies the drug's effect on cancer cells while minimizing its impact on normal cells, achieving desirable selectivity for cancer cells. Leveraging nanogold delivery, we successfully facilitated intracellular action of the GPX4-targeting peptide PROTAC drug, denoted as Au-PGPD (peptide GPX4 PROTAC drug). Au-PGPD effectively induced GPX4 degradation and inhibited ALL cell proliferation. Remarkably, Au-PGPD exhibited significantly less efficacy on normal cells, underscoring the selectivity and safety of our design.


Assuntos
Ferroptose , Leucemia-Linfoma Linfoblástico de Células Precursoras , Humanos , Proteólise , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Peptídeos , Apoptose , Quimera de Direcionamento de Proteólise , Proteínas Proto-Oncogênicas c-mdm2
3.
Pharm Res ; 40(1): 307-319, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36471024

RESUMO

PURPOSE: The probability of agglomerate-to-wall collision was quantified using a unique image processing technique applied to high-speed microscopic images. The study aimed to investigate the effects of flow rate and particle size on the percentage of colliding agglomerates detected within an in-house powder dispersion device. METHOD: The device consists of a swirl chamber and two tangential inlets in various configurations, designed to emulate the geometric features of commercial devices such as the Aerolizer® and Osmohaler®. The test cases were conducted with constant flow rates of 30 SLPM and 60 SLPM. Four powder samples were tested, including carrier Respitose® SV010 (median volume diameter 104 µm, span 1.7) and mannitol of three constituent primary particle sizes (3 µm, 5 µm and 7 µm; span 1.6 - 1.9). RESULTS: At the lower flow rate of 30 SLPM, collision frequencies were significantly different between powders of different constituent particle sizes, but the effects of powder properties diminished on increasing the flow rate to 60 SLPM. At the higher flow rate, all powders experienced a significant increase in the proportion of colliding particles. CONCLUSION: Analysis of collision events showed that the probability of collision for each agglomerate increased with agglomerate diameter and velocity. Experimental data of agglomerate-to-wall collision were utilised to develop a logistic regression model that can accurately predict collisions with various powders and flow rates.


Assuntos
Inaladores de Pó Seco , Manitol , Aerossóis , Pós , Tamanho da Partícula , Administração por Inalação
4.
Mol Med ; 28(1): 47, 2022 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-35508972

RESUMO

BACKGROUND: Receptor-interacting protein kinase 2 (RIPK2, also known as RIP2) was reported to be associated with bacterial infections as well as inflammatory responses. However, the role of RIPK2 in prognosis and immunotherapy response is yet to be elucidated in human pan-cancer. METHODS: In this study, we investigated the expression, gene alteration landscape and prognostic value of RIPK2 in 33 cancers through various databases including Ualcan, cBioportal and Gene Expression Profiling Interactive Analysis 2 (GEPIA2). Then, the correlation between RIPK2 and immune infiltration, immune score, stromal score, and ESTIMATE score was investigated in the Cancer Genome Atlas (TCGA) and tumor immune estimation resource (TIMER) databases. Independent cohorts were utilized to explore the role of RIPK2 in tumor immunotherapy response. Furthermore, Gene set enrichment analysis (GSEA) was conducted to explore the mechanisms by which RIPK2 regulates immune therapy resistance. Single-cell RNA-seq datasets were used to analyze the expression level of RIPK2 on different immune cells. Moreover, CellMiner database was used to explore the relationship between RIPK2 expression with drug response. RESULT: Compared with normal tissue, tumor tissue had a higher expression level of RIPK2 in various cancers. Survival analysis showed that high expression of RIPK2 associated with poor prognosis in numerous cancers. RIPK2 was found to promote a series of immune cell infiltration and B cells, macrophages, and neutrophils were significantly positively correlated with the expression of RIPK2. Moreover, RIPK2 affected immune score, stromal score and ESTIMATE score for a wide range of cancers. In the vast majority of 33 cancers, gene co-expression analysis showed that RIPK2 was positively correlated with the expression of immune checkpoint markers, such as PDCD1 (PD-1), CD274 (PD-L1), CTLA4 and TIGIT. RIPK2 aggravated cytotoxic T lymphocyte (CTL) dysfunction and related to the poor efficacy of immune checkpoint blockade in skin cutaneous melanoma (SKCM) and kidney renal clear cell carcinoma (KIRC). High expression of RIPK2 promoted innate immunotherapy resistance and adaptive immunotherapy resistance through IL-6/JAK/STAT3 signaling, interferon-gamma response, and interferon-alpha response pathway. CONCLUSIONS: These results confirmed that RIPK2 could serve as a prognostic biomarker and promoted immune therapy resistance via triggering cytotoxic T lymphocytes dysfunction.


Assuntos
Carcinoma de Células Renais , Neoplasias Renais , Melanoma , Neoplasias Cutâneas , Biomarcadores Tumorais/genética , Carcinoma de Células Renais/genética , Carcinoma de Células Renais/metabolismo , Carcinoma de Células Renais/patologia , Feminino , Humanos , Neoplasias Renais/genética , Neoplasias Renais/metabolismo , Neoplasias Renais/patologia , Masculino , Proteína Serina-Treonina Quinase 2 de Interação com Receptor/genética , Proteína Serina-Treonina Quinase 2 de Interação com Receptor/metabolismo , Linfócitos T Citotóxicos/metabolismo , Linfócitos T Citotóxicos/patologia , Melanoma Maligno Cutâneo
5.
Appl Environ Microbiol ; 88(5): e0249921, 2022 03 08.
Artigo em Inglês | MEDLINE | ID: mdl-35044833

RESUMO

The discovery of new and efficient genetic engineering technologies for Agrobacterium will broaden the capacity for fundamental research on this genus and its utilization as a transgenic vehicle. In this study, we aim to develop an efficient recombineering system for Agrobacterium species. We examined isolates of Agrobacterium and the closely related genus Rhizobium to identify pairs of ET-like recombinases that would aid in the recombineering of Agrobacterium species. Four pairs of ET-like recombinases, named RecETh1h2h3h4AGROB6, RecETh1h2P3RHI597, RecETRHI145, and RecEThRHI483, were identified in Agrobacterium tumefaciens strain B6, Rhizobium leguminosarum bv. trifolii WSM597, Rhizobium sp. strain LC145, and Rhizobium sp. strain Root483D2, respectively. Eight more candidate recombineering systems were generated by combining the new ET-like recombinases with Redγ or Pluγ. The PluγETRHI145 system, the RecETh1h2h3h4AGROB6 system, and the PluγEThRHI483 system were determined to be the most efficient recombineering systems for the type strains A. tumefaciens C58, A. tumefaciens EHA105, and Rhizobium rhizogenes NBRC 13257, respectively. The utility of these systems was demonstrated by knocking out the istB-istA fusion gene in C58, the celI gene in EHA105, and the 3'-to-5' exonuclease gene and endoglucanase gene in NBRC 13257. Our work provides an effective genetic manipulation strategy for Agrobacterium species. IMPORTANCEAgrobacterium is a powerful transgenic vehicle for the genetic manipulation of numerous plant and fungal species and even animal cells. In addition to improving the utility of Agrobacterium as a transgenic vehicle, genetic engineering tools are important for revealing crucial components that are functionally involved in transfer DNA (T-DNA) translocation events. This work developed an efficient and versatile recombineering system for Agrobacterium. The successful genome modification of Agrobacterium strains revealed that this new recombineering system could be used for the genetic engineering of Agrobacterium.


Assuntos
Rhizobium leguminosarum , Rhizobium , Agrobacterium tumefaciens/genética , Engenharia Genética , Recombinases , Rhizobium/genética
6.
Magn Reson Med ; 86(3): 1647-1661, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-33821529

RESUMO

PURPOSE: To propose a reconstruction framework to generate accurate T1 maps for a fast MR T1 mapping sequence. METHODS: A deep learning-enhanced T1 mapping method with spatial-temporal and physical constraint (DAINTY) was proposed. This method explicitly imposed low-rank and sparsity constraints on the multiframe T1 -weighted images to exploit the spatial-temporal correlation. A deep neural network was used to efficiently perform T1 mapping as well as denoise and reduce undersampling artifacts. Additionally, the physical constraint was used to build a bridge between low-rank and sparsity constraint and deep learning prior, so the benefits of constrained reconstruction and deep learning can be both available. The DAINTY method was trained on simulated brain data sets, but tested on real acquired phantom, 6 healthy volunteers, and 7 atherosclerosis patients, compared with the narrow-band k-space-weighted image contrast filter conjugate-gradient SENSE (NK-CS) method, kt-sparse-SENSE (kt-SS) method, and low-rank plus sparsity (L+S) method with least-squares T1 fitting and direct deep learning mapping. RESULTS: The DAINTY method can generate more accurate T1 maps and higher-quality T1 -weighted images compared with other methods. For atherosclerosis patients, the intraplaque hemorrhage can be successfully detected. The computation speed of DAINTY was 10 times faster than traditional methods. Meanwhile, DAINTY can reconstruct images with comparable quality using only 50% of k-space data. CONCLUSION: The proposed method can provide accurate T1 maps and good-quality T1 -weighted images with high efficiency.


Assuntos
Aprendizado Profundo , Algoritmos , Artefatos , Encéfalo/diagnóstico por imagem , Humanos , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Imagens de Fantasmas
7.
Soft Matter ; 14(21): 4404-4410, 2018 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-29781015

RESUMO

The discrete element method (DEM) was used to simulate the piling of rod-like (elongated sphero-cylindrical) particles, mainly focusing on the effect of particle shape on the structural and force properties of the piles. In this work, rod-like particles of different aspect ratios were discharged on a flat surface to form wedge-shaped piles. The surface properties of the piles were characterized in terms of angle of repose and stress at the bottom of the piles. The results showed that the rise of the angle of repose became slower with the increase of particle aspect ratio. The pressure dip underneath the piles reached the maximum when the particle aspect ratio was around 1.6, beyond which the pressure dip phenomenon became attenuated. Both the pressure dip and the shear stress dip were quantitatively examined. The structure and forces inside the piles were further analyzed to understand the change in pressure dip, indicating that "bridging" or "arching" structures within the piles were the cause of the pressure dip.

8.
Pharm Res ; 32(6): 2086-96, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25511919

RESUMO

PURPOSE: Carrier-based dry powder inhalers (DPIs) are widely used for rapid and convenient delivery of drug to the site of action. This work aimed to predict powder aerosolisation in DPIs through numerical modelling. METHODS: A multi-scale modelling technique based on the combined computational fluid dynamics (CFD) and discrete element method (DEM) approach was developed. RESULTS: The simulation results of the detachments of the drug particles from single carrier under different impact velocities and angles were comparable with those measured in the experiments in terms of fine particle fraction FPF loaded . Empirical equations were developed to link the detachment performance with impact velocity and impact angle. Then the dynamics of the carrier particles in Aerolizer® was simulated. The results indicated that the carrier-wall impaction was the dominant mechanism for drug aerosolisation performance. By linking the empirical equations with the carrier-wall impact energy, the predictions showed that for a given formulation mass with a fixed carrier/drug ratio, the inhaler performance decreased with carrier size and increased with air flow rate. Device empty efficiency, however, was independent with carrier size and flow rate. CONCLUSIONS: The multi-scale model was able to provide quantitative information to better understand the aerosolisation mechanisms of carrier-based formulation.


Assuntos
Simulação por Computador , Portadores de Fármacos , Inaladores de Pó Seco , Modelos Teóricos , Preparações Farmacêuticas/química , Administração por Inalação , Aerossóis , Química Farmacêutica , Desenho de Equipamento , Movimento (Física) , Análise Numérica Assistida por Computador , Preparações Farmacêuticas/administração & dosagem , Pós , Fatores de Tempo
9.
Curr Med Chem ; 2024 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-38549532

RESUMO

Oridonin is a tetracyclic diterpenoid compound extracted from the medicinal herb Isodon and related species. Since 1976, studies have reported the significant anti-tumor activity of oridonin in vivo. Recently, an increasing number of studies have confirmed the anti-tumor effects of oridonin in various types of cancers, and its effect on hematological malignancies stands out. Herein, we have systematically reviewed the anti-- tumor effects of oridonin and its specific mechanisms in hematological malignancies, including the regulation of cancer proteins, activation of intrinsic and extrinsic apoptosis signaling pathways, accumulation of reactive oxygen species (ROS), modulation of chaperone proteins and miRNA expression, combination therapy with chemotherapeutic drugs, and the development of its derivatives. Taken together, oridonin exhibits multiple anti-tumor activities and serves as a multi-target agent, making it worthy of further investigation.

10.
Int J Pharm ; 657: 124165, 2024 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-38663643

RESUMO

Aerosol drug delivery in the human airway is significantly affected by the morphology and size of the airway. This work developed a CFD-DEM model to simulate and analyze air flow and powder dynamics in combined inhaler-airway systems with different degrees of airway deformation (non-deformed, 50%, and 75% deformed) and sizes (adult, 0.80, and 0.62 scaled). The airways were generated based on a regular airway constructed from the MRI images through finite element method (for deformed airways) or scaling-down (for smaller airways). The airways were connected to Turbuhaler® through a connector. The results showed that under the same flow rate, the variation in the airway geometry and size had a minimum impact on the flow field and powder deposition in the device and the connector. However, deformation caused more particle deposition in the deformed region. Notably, the airway with 50% deformation had the most particles passing through the airway with the largest particle sizes due to its lower air velocity in the deformed area. Reducing airway size resulted in more powder deposition on the airway, particularly at the pharynx and mouth regions. This was because, with the same flow rate, the flow velocity in the smaller airway was higher, causing more particle-wall collisions in the mouth and pharynx regions. More importantly, the deposition efficiency in the 0.62-scaled airway was significantly higher than the other two airways, highlighting the importance of the different administration of aerosol drugs for young children.


Assuntos
Aerossóis , Tamanho da Partícula , Pós , Humanos , Administração por Inalação , Inaladores de Pó Seco , Sistemas de Liberação de Medicamentos , Sistema Respiratório , Imageamento por Ressonância Magnética , Faringe/anatomia & histologia , Adulto , Simulação por Computador
11.
Sci Rep ; 14(1): 12231, 2024 05 28.
Artigo em Inglês | MEDLINE | ID: mdl-38806549

RESUMO

As the world's first oral nuclear export inhibitor, selinexor is increasingly being used in clinical applications for malignant tumors. However, there is no extensive exploration on selinexor's adverse events (ADEs), necessitating a real-word assessment of its clinical medication safety. FAERS data (July 2019-June 2023) were searched for selinexor ADE reports across all indications. Use the system organ class (SOC) and preferred terms (PT) from the medical dictionary for regulatory activities (MedDRA) to describe, categorize, and statistic ADEs. Disproportionality analysis was employed through calculation of reporting odds ratio (ROR) and proportional reporting ratio (PRR). Based on total of 4392 selinexor related ADE reports as the primary suspect (PS), of which 2595 instances were severe outcomes. The predominant ADEs included gastrointestinal disorders, myelosuppression symptoms, and various nonspecific manifestations. 124 signals associated with selinexor ADE were detected, and 10 of these top 15 signals were not included into the instructions. Our study provides real-world evidence regarding the drug safety of selinexor, which is crucial for clinicians to safeguard patients' health.


Assuntos
Proteína Exportina 1 , Hidrazinas , Receptores Citoplasmáticos e Nucleares , Triazóis , Humanos , Hidrazinas/efeitos adversos , Triazóis/efeitos adversos , Receptores Citoplasmáticos e Nucleares/antagonistas & inibidores , Sistemas de Notificação de Reações Adversas a Medicamentos/estatística & dados numéricos , Carioferinas/antagonistas & inibidores , Bases de Dados Factuais , Masculino , Feminino , Pessoa de Meia-Idade , Adulto , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/epidemiologia , Idoso
12.
Int J Pharm ; 637: 122871, 2023 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-36948474

RESUMO

Powder dispersion in dry powder inhalers (DPIs) is affected by powder formulations as well as the design of a device. This paper conducted a numerical investigation based on the coupled computational fluid dynamics (CFD) and discrete element method (DEM) to evaluate the changes of the design of a commercial DPI device Turbuhaler® on the aerosolization of an API-only formulation. Six different designs were proposed by modifying the mouthpiece and chamber of the original geometry which was reconstructed from a CT-scan of the Turbuhaler, and their performances in terms of powder deposition in the device and fine powder fraction (FPF) were evaluated. The resistance of the device was observed to vary with different designs. For the change of the mouthpiece, the device with a cylindrical mouthpiece had the least resistance and the lowest FPF emitted among all the devices, confirming the important role of the spiral mouthpiece on powder dispersion. Reducing the mouthpiece size caused more powder deposition in the inhaler due to higher airflow velocity, but FPF emitted increased compared to the original design as more powder dispersion occurred inside the mouthpiece. The half-length mouthpiece design reduced device resistance to increase airflow velocity and average collision energy, resulting in an increase in FPF loaded but a decrease in the number of collisions. For the change of the chamber, the domed chamber design increased the powder dispersion time and thus enhanced the frequency and energy of particle collisions, which eventually led to an increase in FPF loaded. At fixed flow rates, the powder dispersion efficiency was a function of the device resistance with higher device resistance causing an increase in the FPF loaded. However, it is important for the patient's attainable pressure drop to be considered in this context. Correlations between the aerosolization efficiency and the ratio of the average collision energy and cohesion energy were established based on model-predicted quantities.


Assuntos
Inaladores de Pó Seco , Hidrodinâmica , Humanos , Pós , Aerossóis , Tamanho da Partícula , Administração por Inalação , Desenho de Equipamento
13.
Front Immunol ; 14: 1249731, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37928544

RESUMO

Introduction: OAS1(2'-5'-oligoadenylate synthetase 1) is a member of the Interferon-Stimulated Genes which plays an important role in the antiviral process. In recent years, the role of OAS1 in tumors has attracted attention, and it was found to be associated with prognosis in several tumors. However, the mechanism by which OAS1 affects tumors is unclear and pan-cancer study of OAS1 is necessary to better understand its implication in cancers. Methods: The expression, prognostic value, genetic alteration, alternative splicing events of OAS1 in pan-cancers were analyzed using TCGA, GTEx, HPA, GEPIA and OncoSplicing databases. OAS1 associated immune cell infiltration was evaluated using the ESTIMATE, xCell, CIBERSORT and QUANTISEQ algorithm. Single cell transcriptome data download using TISH database. Finally, the roles of the OAS1 on apoptosis, migration and invasion were investigated in two pancreatic cancer cells. Results: Our results revealed significant differences in OAS1 expression among various tumors, which had prognostic implications. In addition, we investigated the impact of OAS1 on genomic stability, methylation status, and other factors across different types of cancer, and the effects of these factors on prognosis. Notably, our study also demonstrated that OAS1 overexpression can contribute to CTL dysfunction and macrophage M2 polarization. In addition, cell experiments showed that the knockdown of OAS1 could reduce the invasive ability and increased the apoptosis rate of PAAD cells. Discussion: These results confirmed that OAS1 could be a prognostic biomarker and therapeutic target for its potential role in CTL dysfunction and macrophage M2 polarization.


Assuntos
Interferons , Neoplasias Pancreáticas , Humanos , Prognóstico , Multiômica , Biomarcadores , 2',5'-Oligoadenilato Sintetase/genética
14.
Int J Pharm ; 647: 123556, 2023 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-37890648

RESUMO

Capsule based dry powder inhalers (DPIs) often require piercing of the capsule before inhalation, and the characteristics of the apertures (punctured holes) affect air flow and the release of powders from the capsule. This work develops a numerical model based on the two-way coupling of computational fluid dynamics and discrete element method (CFD-DEM) to investigate the effect of aperture size on powder dispersion in the Aerolizer® device loaded with only carrier particles (lactose). Powders (carrier particles) in the size range 60-140 µm (d50: 90 µm and span: 0.66) were initialized in a capsule which had a circular aperture at each end. Boundary conditions corresponding to an air flow rate of 45 L/min were specified at each inlet to the mixing chamber (i.e., a total flow rate 90 L/min), and a capsule spin speed of âˆ¼ 4050 rpm. The velocity magnitudes inside the capsule were considerably lower than those in the mixing chamber in the vicinity of the rotating capsule, with the exception of the capsules featuring 2.5 mm and 4 mm apertures. Larger apertures reduced the capsule emptying time and increased the particle evacuation velocity; the fluid drag force on the particles issuing from the capsule peaked for an aperture of 1.3 mm. Inside the capsule, particle-particle (PP) collisions were more frequent than particle-wall (PW) collisions due to high concentration of powder, but PP collisions had smaller (median) impact energy than PW collisions. Larger apertures resulted in fewer collisions in the capsule with higher PW and virtually unchanged PP collision energies. Outside the capsule (i.e., in the inhaler mixing chamber), PW collisions occurred more frequently than PP collisions with median collision energies typically two orders of magnitude higher than inside the capsule. Larger apertures resulted in more collisions with slightly reduced collision energy, but this effect plateaued for aperture sizes larger than 1.3 mm. Powder dispersion, expressed as the fine particle fraction (FPF) of the powder, was predicted using an empirical equation based on carrier PW collisions. Therefore, consistent with the model prediction of the effect of aperture sizes on the chamber collision frequency, FPF increased with aperture size but plateaued beyond 1.3 mm.


Assuntos
Inaladores de Pó Seco , Hidrodinâmica , Aerossóis , Pós , Administração por Inalação , Tamanho da Partícula , Desenho de Equipamento
15.
Int J Pharm ; 642: 123152, 2023 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-37339687

RESUMO

The effect of capsule aperture size on the aerosol performance of lactose blend formulation was studied using Foradil® (containing 12 µg of formoterol fumarate (FF1) and 24 mg of lactose) dispersed with a powder inhaler Aerolizer® at increasing air flowrates. Apertures sizes of 0.4, 1.0, 1.5, 2.5, and 4.0 mm were introduced at the opposite ends of the capsule. The formulation was dispersed into a Next Generation Impactor (NGI) at 30, 60 and 90 L/min, with the fine particle fractions (FPFrec and FPFem) measured by chemical assay of FF and lactose using high-performance liquid chromatography. Particle size distribution (PSD) of FF particles dispersed in wet media was also characterized by laser diffraction. FPFrec showed a stronger dependency on the flowrate than the capsule aperture size. The most efficient dispersion was achieved at 90 L/min. At a given flowrate, FPFem remained broadly constant across different aperture sizes. The laser diffraction studies demonstrated the presence of large agglomerates.


Assuntos
Lactose , Nebulizadores e Vaporizadores , Administração por Inalação , Lactose/química , Aerossóis/química , Fumarato de Formoterol , Tamanho da Partícula , Inaladores de Pó Seco , Pós
16.
Pharm Res ; 29(7): 1797-807, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22327971

RESUMO

PURPOSE: We hypothesize that the USP induction port may de-agglomerate carrier-free powder emitting from dry powder inhalers (DPIs). METHODS: Aerosols emitting from a range of DPIs (Spinhaler®, Turbuhaler® and Osmohaler™) and induction ports (USP throat, straight tube, Alberta idealized mouth-throat geometry (AG)) were sized by laser diffraction. Total drug recovery was obtained by HPLC and fine particle fraction computed. Air flow patterns were simulated using Computational Fluid Dynamics (CFD). RESULTS: The straight tube did not de-agglomerate emitted powder. However, the USP throat and AG further de-agglomerated powders from the Spinhaler, but not the Turbuhaler and Osmohaler. While budesonide powder deposited similarly in all induction ports, deposition was significantly higher in the AG for both DSCG and mannitol. CFD revealed agglomerates impacting on the USP throat with higher localized velocity compared with the straight tube. CFD further showed a more complex flow pattern with high-velocity air jets in the AG, which explains the higher FPF for DSCG and the lower FPF for mannitol using the AG. CONCLUSION: The USP throat further de-agglomerated the emitted powder from the DPI when it did not sufficiently disperse the powder. Other tools such as laser diffraction may be used for cross-examining to avoid artifacts in the results.


Assuntos
Broncodilatadores/administração & dosagem , Budesonida/administração & dosagem , Inaladores de Pó Seco/instrumentação , Manitol/administração & dosagem , Administração por Inalação , Aerossóis , Desenho de Equipamento , Humanos , Hidrodinâmica , Tamanho da Partícula , Pós , Estados Unidos
17.
J Agric Food Chem ; 69(3): 982-991, 2021 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-33427450

RESUMO

Lipopolysaccharide (LPS)-induced liver injury is the main factor in acute liver failure. The current study aims to investigate the protection of limonin, an antioxidant compound from citrus fruit, against LPS-induced liver toxicity and elucidate the potential mechanisms. We found that limonin elevated cell viability and reduced LDH release in LPS-treated HepG2 cells. Limonin also inhibited LPS-induced pyroptosis by inhibiting membrane rupture, reducing ROS generation, and decreasing gasdermin D activation. Moreover, limonin inhibited the formation of a NOD-like receptor protein 3 (NLRP3)/Apoptosis-associated speck-like protein containing a CARD (ASC) complex by reducing the related protein expression and the colocalization cytosolic of NLRP3 and caspase-1 and then suppressed IL-1ß maturation. Ultimately, we established LPS-induced hepatotoxicity in vivo by using C57BL/6 mice administrated LPS (10 mg/kg) intraperitoneally and limonin (50 and 100 mg/kg) orally. We found that limonin dereased the serum ALT and AST activity and LDH release and increased the hepatic GSH amount in LPS-treated mice. Additionally, the liver histological evaluation revealed that limonin protects against LPS-induced liver damage. We further demonstrated that limonin ameliorated LPS-induced hepatotoxicity by inhibiting pyroptosis via the NLRP3/gasdermin D signaling pathway. In summary, this study uncovered the mechanism whereby limonin mitigated LPS-induced hepatotoxicity and documented that limonin might be a promising candidate drug for LPS-induced hepatotoxicity.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas/tratamento farmacológico , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Proteínas de Ligação a Fosfato/metabolismo , Piroptose/efeitos dos fármacos , Animais , Caspase 1/genética , Caspase 1/metabolismo , Doença Hepática Induzida por Substâncias e Drogas/etiologia , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Doença Hepática Induzida por Substâncias e Drogas/fisiopatologia , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Limoninas , Lipopolissacarídeos/efeitos adversos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Proteínas de Ligação a Fosfato/genética
18.
IEEE J Biomed Health Inform ; 25(9): 3564-3575, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34038373

RESUMO

Recent fMRI connectivity-based parcellation (CBP) methods have been developed to obtain homogeneous and functionally coherent brain parcels. However, most of these studies utilize traditional clustering methods that neglect hidden nonlinear features. To enhance parcellation performance, here we propose a deep embedded connectivity-based parcellation (DECBP) framework and apply it to determine functional subdivisions of the striatum in public resting state fMRI data sets. This framework integrates fMRI connectivity features into deep embedded clustering (DEC), a deep neural network based on a stacked autoencoder. Compared to three prevalent clustering methods and their combinations with principal component analysis (PCA), the DECBP exhibited a significantly higher similarity between scans, individuals, and groups, indicating enhanced reproducibility. The generated reliable parcellations were also largely consistent with other public atlases. We further explored the functional subunits in the striatum in a data set from 23 Parkinson's disease (PD) subjects and 27 age-matched healthy controls (HC). All putaminal subregions of PD demonstrated lower interhemispheric connectivity than those of HC, which might reflect imbalance in the pathological progression of PD. Such hypo-connectivity was also observed between putaminal subregions and other brain regions, reflecting neuroimaging manifestations of the altered cortico-striato-thalamo-cortical circuit. These observed weaker couplings were associated with PD severity and duration. Our results support the utilization of the DECBP framework and suggest that abnormal connectivity in putaminal subregions may be a potential indicator of PD.


Assuntos
Doença de Parkinson , Mapeamento Encefálico , Análise por Conglomerados , Humanos , Imageamento por Ressonância Magnética , Vias Neurais , Doença de Parkinson/diagnóstico por imagem , Reprodutibilidade dos Testes
19.
Int Immunopharmacol ; 90: 107161, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33168409

RESUMO

Inflammatory bowel disease (IBD) is a chronic gastrointestinal inflammation regulated by intricate mechanisms. Limonin, a natural tetracyclic triterpenoid compound, possesses multiple bioactivities including anti-inflammation, anti-cancer and so on. However, the therapeutic potential and the underlying mechanism of limonin on IBD remain unclear. Here, we probe into the effect of limonin on chronic colitis induced by dextran sulfate sodium (DSS) and illustrated the potential mechanisms. We found that limonin relieved the risk and severity of DSS-induced chronic colitis in mice through various aspects including increasing body weight and colon length, decreasing the mortality rate, inhibiting MPO activity and improving colon pathology. Limonin also decreased the production of proinflammatory cytokines TNF-α, IL-1ß, IL-6 and the expression of inflammatory proteins COX-2, iNOS in colon tissues from DSS-induced colitis mice. Moreover, limonin attenuated DSS-induced chronic colitis by inhibiting PERK-ATF4-CHOP pathway of endoplasmic reticulum (ER) stress and NF-κB signaling. In vitro, limonin not only decreased LPS-induced higher production of pro-inflammatory cytokines and inflammatory proteins mentioned above by inhibiting NF-κB signaling in macrophage cells RAW264.7, but also suppressed PERK-ATF4-CHOP pathway of ER stress. In summary, our study demonstrated that limonin mitigated DSS-induced chronic colitis via inhibiting PERK-ATF4-CHOP pathway of ER stress and NF-κB signaling. All of this study provides the possibility for limonin as an effective drug for chronic colitis of IBD in the future.


Assuntos
Anti-Inflamatórios/uso terapêutico , Colite/tratamento farmacológico , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Inflamação/tratamento farmacológico , Limoninas/uso terapêutico , Transdução de Sinais/efeitos dos fármacos , Fator 4 Ativador da Transcrição/metabolismo , Animais , Colite/induzido quimicamente , Citocinas/efeitos dos fármacos , Citocinas/metabolismo , Sulfato de Dextrana/farmacologia , Inflamação/induzido quimicamente , Lipopolissacarídeos/farmacologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , NF-kappa B/metabolismo , Células RAW 264.7 , Fator de Transcrição CHOP/metabolismo , eIF-2 Quinase/metabolismo
20.
Adv Drug Deliv Rev ; 170: 369-385, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-32971228

RESUMO

Effective evaluation and prediction of aerosol transport deposition in the human respiratory tracts are critical to aerosol drug delivery and evaluation of inhalation products. Establishment of an in vitro-in vivo correlation (IVIVC) requires the understanding of flow and aerosol behaviour and underlying mechanisms at the microscopic scale. The achievement of the aim can be facilitated via computational fluid dynamics (CFD) based in silico modelling which treats the aerosol delivery as a two-phase flow. CFD modelling research, in particular coupling with discrete phase model (DPM) and discrete element method (DEM) approaches, has been rapidly developed in the past two decades. This paper reviews the recent development in this area. The paper covers the following aspects: geometric models of the respiratory tract, CFD turbulence models for gas phase and its coupling with DPM/DEM for aerosols, and CFD investigation of the effects of key factors associated with geometric variations, flow and powder characteristics. The review showed that in silico study based on CFD models can effectively evaluate and predict aerosol deposition pattern in human respiratory tracts. The review concludes with recommendations on future research to improve in silico prediction to achieve better IVIVC.


Assuntos
Aerossóis/química , Hidrodinâmica , Sistema Respiratório/química , Administração por Inalação , Aerossóis/administração & dosagem , Sistemas de Liberação de Medicamentos , Humanos , Modelos Moleculares
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