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2.
Biomater Adv ; 159: 213823, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38460353

RESUMO

Lung cancer, one of the most common causes of high mortality worldwide, still lacks appropriate and convenient treatment options. Photodynamic therapy (PDT) has shown promising results against cancer, especially in recent years. However, pulmonary drug delivery of the predominantly hydrophobic photosensitizers still represents a significant obstacle. Nebulizing DPPC/Cholesterol liposomes loaded with the photosensitizer curcumin via a vibrating mesh nebulizer might overcome current restrictions. In this study, the liposomes were prepared by conventional thin-film hydration and two other methods based on dual centrifugation. The liposomes' physicochemical properties were determined before and after nebulization, showing that liposomes do not undergo any changes. However, morphological characterization of the differently prepared liposomes revealed structural differences between the methods in terms of lamellarity. Internalization of curcumin in lung adenocarcinoma (A549) cells was visualized and quantified. The generation of reactive oxygen species because of the photoreaction was also proven. The photodynamic efficacy of the liposomal formulations was tested against A549 cells. They revealed different phototoxic responses at different radiant exposures. Furthermore, the photodynamic efficacy was investigated after nebulizing curcumin-loaded liposomes onto xenografted tumors on the CAM, followed by irradiation, and evaluated using positron emission tomography/computed tomography and histological analysis. A decrease in tumor metabolism could be observed. Based on the efficacy of curcumin-loaded liposomes in 2D and 3D models, liposomes, especially with prior film formation, can be considered a promising approach for PDT against lung cancer.


Assuntos
Curcumina , Neoplasias Pulmonares , Humanos , Lipossomos/uso terapêutico , Curcumina/farmacologia , Curcumina/uso terapêutico , Sistemas de Liberação de Medicamentos , Nebulizadores e Vaporizadores , Fármacos Fotossensibilizantes/uso terapêutico , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/patologia
3.
Eur J Pharm Sci ; 196: 106748, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38471594

RESUMO

Lung cancer is one of the most common causes of high mortality worldwide. Current treatment strategies, e.g., surgery, radiotherapy, chemotherapy, and immunotherapy, insufficiently affect the overall outcome. In this study, we used curcumin as a natural photosensitizer in photodynamic therapy and encapsulated it in liposomes consisting of stabilizing tetraether lipids aiming for a pulmonary drug delivery system against lung cancer. The liposomes with either hydrolyzed glycerol-dialkyl-glycerol tetraether (hGDGT) in different ratios or hydrolyzed glycerol-dialkyl-nonitol tetraether (hGDNT) were prepared by dual centrifugation (DC), an innovative method for liposome preparation. The liposomes' physicochemical characteristics before and after nebulization and other nebulization characteristics confirmed their suitability. Morphological characterization using atomic force and transmission electron microscopy showed proper vesicular structures indicative of liposomes. Qualitative and quantitative uptake of the curcumin-loaded liposomes in lung adenocarcinoma (A549) cells was visualized and proven. Phototoxic effects of the liposomes were detected on A549 cells, showing decreased cell viability. The generation of reactive oxygen species required for PDT and disruption of mitochondrial membrane potential were confirmed. Moreover, the chorioallantoic membrane (CAM) model was used to further evaluate biocompatibility and photodynamic efficacy in a 3D cell culture context. Photodynamic efficacy was assessed by PET/CT after nebulization of the liposomes onto the xenografted tumors on the CAM with subsequent irradiation. The physicochemical properties and the efficacy of tetraether lipid liposomes encapsulating curcumin, especially liposomes containing hGDNT, in 2D and 3D cell cultures seem promising for future PDT usage against lung cancer.

4.
Mol Plant Microbe Interact ; 37(3): 250-263, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38416124

RESUMO

Fungal pathogens deploy a set of molecules (proteins, specialized metabolites, and sRNAs), so-called effectors, to aid the infection process. In comparison to other plant pathogens, smut fungi have small genomes and secretomes of 20 Mb and around 500 proteins, respectively. Previous comparative genomic studies have shown that many secreted effector proteins without known domains, i.e., novel, are conserved only in the Ustilaginaceae family. By analyzing the secretomes of 11 species within Ustilaginaceae, we identified 53 core homologous groups commonly present in this lineage. By collecting existing mutants and generating additional ones, we gathered 44 Ustilago maydis strains lacking single core effectors as well as 9 strains containing multiple deletions of core effector gene families. Pathogenicity assays revealed that 20 of these 53 mutant strains were affected in virulence. Among the 33 mutants that had no obvious phenotypic changes, 13 carried additional, sequence-divergent, structurally similar paralogs. We report a virulence contribution of seven previously uncharacterized single core effectors and of one effector family. Our results help to prioritize effectors for understanding U. maydis virulence and provide genetic resources for further characterization. [Formula: see text] Copyright © 2024 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license.


Assuntos
Basidiomycota , Ustilaginales , Ustilago , Virulência/genética , Ustilago/genética , Doenças das Plantas/microbiologia , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Zea mays/microbiologia
5.
J Neurol ; 271(3): 1462-1468, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38032371

RESUMO

BACKGROUND: Transcranial Pulse Stimulation (TPS) has been recently introduced as a novel ultrasound neuromodulation therapy with the potential to stimulate the human brain in a focal and targeted manner. Here, we present a first retrospective analysis of TPS as an add-on therapy for Parkinson's disease (PD), focusing on feasibility, safety, and clinical effects. We also discuss the placebo response in non-invasive brain stimulation studies as an important context. METHODS: This retrospective clinical data analysis included 20 PD patients who received ten sessions of TPS intervention focused on the individual motor network. Safety evaluations were conducted throughout the intervention period. We analyzed changes in motor symptoms before and after TPS treatment using Unified Parkinson's Disease Rating Scale part III (UPDRS-III). RESULTS: We found significant improvement in UPDRS-III scores after treatment compared to baseline (pre-TPS: 16.70 ± 8.85, post-TPS: 12.95 ± 8.55; p < 0.001; Cohen's d = 1.38). Adverse events monitoring revealed no major side effects. CONCLUSION: These preliminary findings suggest that TPS can further improve motor symptoms in PD patients already on optimized standard therapy. Findings have to be evaluated in context with the current literature on placebo effects.


Assuntos
Doença de Parkinson , Terapia por Ultrassom , Humanos , Doença de Parkinson/terapia , Estudos Retrospectivos , Terapia por Ultrassom/efeitos adversos , Ultrassonografia , Encéfalo
6.
ACS Appl Bio Mater ; 6(12): 5502-5514, 2023 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-38016693

RESUMO

Natural photosensitizers, such as curcumin or parietin, play a vital role in photodynamic therapy (PDT), causing a light-mediated reaction that kills cancer cells. PDT is a promising treatment option for glioblastoma, especially when combined with nanoscale drug delivery systems. The curcumin- or parietin-loaded lipid nanoparticles were prepared via dual asymmetric centrifugation and subsequently characterized through physicochemical analyses including dynamic light scattering, laser Doppler velocimetry, and atomic force microscopy. The combination of PDT and lipid nanoparticles has been evaluated in vitro regarding uptake, safety, and efficacy. The extensive and well-vascularized chorioallantois membrane (CAM) of fertilized hen's eggs offers an optimal platform for three-dimensional cell culture, which has been used in this study to evaluate the photodynamic efficacy of lipid nanoparticles against glioblastoma cells. In contrast to other animal models, the CAM model lacks a mature immune system in an early stage, facilitating the growth of xenografts without rejection. Treatment of xenografted U87 glioblastoma cells on CAM was performed to assess the effects on tumor viability, growth, and angiogenesis. The xenografts and the surrounding blood vessels were targeted through topical application, and the effects of photodynamic therapy have been confirmed microscopically and via positron emission tomography and X-ray computed tomography. Finally, the excised xenografts embedded in the CAM were analyzed histologically by hematoxylin and eosin and KI67 staining.


Assuntos
Curcumina , Glioblastoma , Fotoquimioterapia , Humanos , Animais , Feminino , Fotoquimioterapia/métodos , Glioblastoma/tratamento farmacológico , Glioblastoma/patologia , Curcumina/farmacologia , Curcumina/uso terapêutico , Galinhas , Linhagem Celular Tumoral
7.
ACS Appl Bio Mater ; 6(6): 2435-2445, 2023 06 19.
Artigo em Inglês | MEDLINE | ID: mdl-37222633

RESUMO

The chorioallantoic membrane (CAM) of fertilized hen's eggs represents a unique and alternative model for cancer research. The CAM model provides an optimal platform for xenografting cancer cell lines and studying essential key factors. Tumor size and growth as well as angiogenesis can be investigated to evaluate the response of therapies and strategies against cancer. Preclinical imaging represented by magnetic resonance imaging and positron emission tomography/computed tomography can generate detailed anatomical and functional information and reveal excellent metabolic sensitivity. In the following, a guideline is introduced in order to find a simplified entrance to the CAM model in combination with modern preclinical imaging techniques. Finally, the presented procedures are additionally completed by histological studies in the form of hematoxylin and eosin as well as immunohistochemical staining.


Assuntos
Membrana Corioalantoide , Neoplasias , Humanos , Animais , Feminino , Membrana Corioalantoide/metabolismo , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Galinhas , Xenoenxertos , Transplante Heterólogo , Imageamento por Ressonância Magnética , Linhagem Celular Tumoral , Neoplasias/metabolismo
8.
Eur J Pharm Biopharm ; 149: 85-94, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32001314

RESUMO

Alveolar osteitis is a complication that can occur after tooth extraction, whereby exposed bone results in severe throbbing pain for the patient and can be prone to infection. The current treatment options are widely regarded as sub-optimal. The aim of this project was to investigate in vitro the plausibility of a dual-action monolithic drug-loaded thermosensitive hydrogel that undergoes thermal gelation within the tooth socket and releases both anaesthetic and antimicrobial agents. Hydrogels containing different levels of lidocaine HCl and metronidazole were prepared based upon Carbopol 934P NF and Pluronic F-127 blends. Membrane-less drug release was determined from the set hydrogels into phosphate buffered saline (PBS) at 37 °C as a function of time, following analysis by HPLC. Gelation characteristics and hydrogel dissolution characteristics were also determined. At 23.38% Pluronic F-127, sol-gel transition commenced at 23 °C and gelation was completely at 37 °C (physiological temperature). Setting times varied with Pluronic content and there was an inverse relationship between drug release and Pluronic content. Sustained and dose dependent release of both drugs was observed at therapeutically relevant levels over 24 h, via a combination of diffusion, dissolution and surface erosion processes. Based on the amounts of drugs released, it was determined that hydrogels containing up to 0.5% lidocaine and 0.1% metronidazole exhibited low risk of cytotoxicity to primary human gingival fibroblasts. In an in vivo scenario, the sol-phase formulation would make contact with all inner surfaces of a tooth socket prior to transitioning to monolithic gel-phase and provide sustained release of lidocaine and metronidazole at sub-toxic levels, thereby providing simultaneous pain relief, protection from ingress of debris and pathological bacteria.


Assuntos
Sistemas de Liberação de Medicamentos , Alvéolo Seco/tratamento farmacológico , Lidocaína/administração & dosagem , Metronidazol/administração & dosagem , Acrilatos/química , Anestésicos Locais/administração & dosagem , Anestésicos Locais/farmacologia , Anestésicos Locais/toxicidade , Anti-Infecciosos/administração & dosagem , Anti-Infecciosos/farmacologia , Anti-Infecciosos/toxicidade , Células Cultivadas , Liberação Controlada de Fármacos , Fibroblastos/efeitos dos fármacos , Gengiva/citologia , Gengiva/efeitos dos fármacos , Humanos , Hidrogéis , Lidocaína/farmacologia , Lidocaína/toxicidade , Metronidazol/farmacologia , Metronidazol/toxicidade , Transição de Fase , Poloxâmero/química , Temperatura
9.
Exp Dermatol ; 27(3): 233-237, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29278440

RESUMO

Pemphigus vulgaris (PV) is a severe autoimmune blistering disease of the skin and mucous membranes. As autoantibodies play an essential role in the disease pathogenesis, the serological detection of anti-desmoglein 3 IgG represents a central tool in the diagnosis of the disease. In this study, we show the validation of a novel lateral flow immunoassay (LFIA) which rapidly detects anti-desmoglein 3 (Dsg3) IgG in human serum. In contrast to other diagnostic procedures, the assay is compact and simple to perform and delivers a fast "yes" or "no" answer within 10 minutes without additional hardware requirements for test evaluation. For validation, a blinded collection of 200 sera including 100 sera from 14 PV patients, 75 sera from 24 bullous pemphigoid patients and 25 sera from 6 patients with pemphigus foliaceus collected at different time points during disease was used. Presence or non-presence of anti-Dsg3 IgG within sera was confirmed using a commercially available Dsg3-ELISA. For qualitative evaluation, Dsg3-LFIA test results were assessed by two independent groups of human observers. Furthermore, quantitative evaluation using POCScan reader was applied. The Dsg3-LFIA demonstrated reliable test results with a sensitivity and specificity of 78.1% and 97.1%, respectively. Test results from POCScan and human observers showed a substantial agreement. The Dsg3-LFIA represents a new diagnostic tool for the immediate and reliable detection of anti-desmoglein 3 serum IgG autoantibodies that does not require additional hardware. Further prospective trials are warranted to validate the Dsg3 LFIA in pemphigus.


Assuntos
Autoanticorpos/sangue , Desmogleína 3/imunologia , Imunoensaio/métodos , Imunoglobulina G/sangue , Pênfigo/sangue , Pênfigo/diagnóstico , Humanos , Penfigoide Bolhoso/sangue , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Método Simples-Cego , Fatores de Tempo
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