Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 11 de 11
Filtrar
1.
Heliyon ; 10(10): e30844, 2024 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-38799753

RESUMEN

Recent advances in the use of nano- and microparticles in drug delivery, cell therapy, and tissue engineering have led to increasing attention towards nanostructured microparticulate formulations for maximum benefit from both nano- and micron sized features. Scalable manufacturing of monodisperse nanostructured microparticles with tunable size, shape, content, and release rate remains a big challenge. Current technology, mainly comprises complex multi-step chemical procedures with limited control over these aspects. Here, we demonstrate a novel technique for high-yield fabrication of monodisperse monolayer and multilayer nanofibrous microparticles (MoNami and MuNaMi respectively). The fabrication procedure includes sequential electrospinning followed by micro-cutting at room temperature and transfer of particles for collection. The big advantage of the introduced technique is the potential to apply several polymer-drug combinations forming multilayer microparticles enjoying extracellular matrix (ECM)-mimicking architecture with tunable release profile. We demonstrate the fabrication and study the factors affecting the final three-dimensional structure. A model drug is encapsulated into a three-layer sheet (PLGA-pullulan-PLGA), and we demonstrate how the release profile changes from burst to sustain by simply cutting particles out of the electrospun sheet. We believe our fabrication method offers a unique and facile platform for realizing advanced microparticles for oral drug delivery applications.

2.
Nat Commun ; 15(1): 3049, 2024 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-38589380

RESUMEN

Raman spectroscopy provides non-destructive, label-free quantitative studies of chemical compositions at the microscale as used on NASA's Perseverance rover on Mars. Such capabilities come at the cost of high requirements for instrumentation. Here we present a centimeter-scale miniaturization of a Raman spectrometer using cheap non-stabilized laser diodes, densely packed optics, and non-cooled small sensors. The performance is comparable with expensive bulky research-grade Raman systems. It has excellent sensitivity, low power consumption, perfect wavenumber, intensity calibration, and 7 cm-1 resolution within the 400-4000 cm-1 range using a built-in reference. High performance and versatility are demonstrated in use cases including quantification of methanol in beverages, in-vivo Raman measurements of human skin, fermentation monitoring, chemical Raman mapping at sub-micrometer resolution, quantitative SERS mapping of the anti-cancer drug methotrexate and in-vitro bacteria identification. We foresee that the miniaturization will allow realization of super-compact Raman spectrometers for integration in smartphones and medical devices, democratizing Raman technology.

3.
Comput Struct Biotechnol J ; 21: 5531-5537, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38034403

RESUMEN

The Cancer Genome Atlas (TCGA) and analogous projects have yielded invaluable tumor-associated genomic data. Despite several web-based platforms designed to enhance accessibility, certain analyses require prior bioinformatic expertise. To address this need, we developed Gene ENrichment Identifier (GENI, https://www.shaullab.com/geni), which is designed to promptly compute correlations for genes of interest against the entire transcriptome and rank them against well-established biological gene sets. Additionally, it generates comprehensive tables containing genes of interest and their corresponding correlation coefficients, presented in publication-quality graphs. Furthermore, GENI has the capability to analyze multiple genes simultaneously within a given gene set, elucidating their significance within a specific biological context. Overall, GENI's user-friendly interface simplifies the biological interpretation and analysis of cancer patient-associated data, advancing the understanding of cancer biology and accelerating scientific discoveries.

4.
Int J Pharm ; 599: 120420, 2021 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-33647404

RESUMEN

In many infected patients, bacterial biofilms represent a mode of growth that significantly enhances the tolerance to antimicrobials, leaving the patients with difficult-to-cure infections. Therefore, there is a growing need for effective treatment strategies to combat biofilm infections. In this work, reservoir-based microdevices, also known as microcontainers (MCs), are co-loaded with two antibiotics: ciprofloxacin hydrochloride (CIP) and colistin sulfate (COL), targeting both metabolically active and dormant subpopulations of the biofilm. We assess the effect of the two drugs in a time-kill study of planktonic P. aeruginosa and find that co-loaded MCs are superior to monotherapy, resulting in complete killing of the entire population. Biofilm consortia of P. aeruginosa grown in flow chambers were not fully eradicated. However, antibiotics in MCs work significantly faster than simple perfusion of antibiotics (62.5 ± 8.3% versus 10.6 ± 10.1% after 5 h) in biofilm consortia, showing the potential of the MC-based treatment to minimize the use of antimicrobials in future therapies.


Asunto(s)
Ciprofloxacina , Colistina , Antibacterianos , Biopelículas , Humanos , Pruebas de Sensibilidad Microbiana , Pseudomonas aeruginosa
5.
Adv Biosyst ; 4(7): e1900289, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-32390341

RESUMEN

Current in vitro drug screening methods often rely on single-cell models and are therefore imprecise in predicting drug absorption, distribution, metabolism, excretion, and toxicity. This study presents a method to fabricate 3D printed inserts that are compatible with commercially available titer plates. Hydrogels can be casted into the inserts and cells can be cultured either in or on the hydrogels. Once individual cell cultures are fully differentiated, the three different cell cultures are stacked on top of each other for biological experiments. To show the possibilities of this approach, three tissue models representing the first pass metabolism is used. The three tissue models are based on gelatin hydrogels and Caco-2, HUVEC, and HepG2 cells to simulate the small intestine, vascular endothelium, and liver, respectively. The device is simple to fabricate, user friendly, and an alternative to microfluidic-based organ on a chip systems. The presented first pass metabolism study allows for gaining information on drug absorption, distribution, metabolism, and, in the future, excretion in one compact device complying the micro titer plate format.


Asunto(s)
Células Endoteliales de la Vena Umbilical Humana/metabolismo , Hidrogeles/química , Dispositivos Laboratorio en un Chip , Técnicas Analíticas Microfluídicas , Modelos Biológicos , Impresión Tridimensional , Andamios del Tejido/química , Células CACO-2 , Evaluación Preclínica de Medicamentos , Células Hep G2 , Humanos , Farmacocinética
6.
Diagnostics (Basel) ; 10(12)2020 Dec 03.
Artículo en Inglés | MEDLINE | ID: mdl-33287458

RESUMEN

BACKGROUND: Disordered eating behaviors (DEBs), including diagnosable eating disorders, are quite common and can interfere with optimal type 1 diabetes (T1DM) management. We explored DEBs prevalence in youth with T1DM, proposing news diagnostic subscales, to represent the clinical dimensions associated with feeding and eating disorders (ED); Methods: additionally to SCOFF questionnaire and Diabetes Eating Problem Survey-Revised (DEPS-R), four subscales combined from the original DEPS-R questionnaire were administered to 40 youths with T1DM (15.0 ± 2.6); Results: females showed higher scores than males in DEPS-R original factor 2 ("preoccupations with thinness/weight", p = 0.024) and in DEPS-R proposed "restriction" factor (p = 0.009). SCOFF scores was correlated with original DEPS-R factors 1 ("maladaptive eating habits") and 2 (p < 0.001) and with the newly proposed DEPS-R factors: restriction, disinhibition, compensatory behaviors, diabetes management (all p < 0.02). Diabetes management was the only factor related to glycated hemoglobin level (p = 0.006). Patients with high DEPS-R score (≥20) scored higher than patients with low (<20) DEPS-R score in DEPS-R original factors 1 (p < 0.001) and 2 (p = 0.002) as well as in the proposed factors including restriction, disinhibition, diabetes management (all p < 0.02); Conclusions: the complicated nature of DEBs calls for the development target specific questionnaires to be used as screening tools to detect cases of DEBs and exclude non cases. Early recognition of DEBs in adolescents with T1DM is essential for effective prevention and successful treatment.

7.
Cell Rep Med ; 1(9): 100156, 2020 12 22.
Artículo en Inglés | MEDLINE | ID: mdl-33377127

RESUMEN

Mode of delivery strongly influences the early infant gut microbiome. Children born by cesarean section (C-section) lack Bacteroides species until 6-18 months of age. One hypothesis is that these differences stem from lack of exposure to the maternal vaginal microbiome. Here, we re-evaluate this hypothesis by comparing the microbial profiles of 75 infants born vaginally or by planned versus emergent C-section. Multiple children born by C-section have a high abundance of Bacteroides in their first few days of life, but at 2 weeks, both C-section groups lack Bacteroides (primarily according to 16S sequencing), despite their difference in exposure to the birth canal. Finally, a comparison of microbial strain profiles between infants and maternal vaginal or rectal samples finds evidence for mother-to-child transmission of rectal rather than vaginal strains. These results suggest differences in colonization stability as an important factor in infant gut microbiome composition rather than birth canal exposure.


Asunto(s)
Bacteroides/patogenicidad , Microbioma Gastrointestinal/inmunología , Transmisión Vertical de Enfermedad Infecciosa , Microbiota/inmunología , Cesárea/métodos , Parto Obstétrico/métodos , Femenino , Humanos , Lactante , Embarazo
8.
Lab Chip ; 19(17): 2905-2914, 2019 09 07.
Artículo en Inglés | MEDLINE | ID: mdl-31367713

RESUMEN

Microfabrication techniques have been applied to develop micron-scale devices for oral drug delivery with a high degree of control over size, shape and material composition. Recently, microcontainers have been introduced as a novel approach to obtain unidirectional release to avoid luminal drug loss, enhance drug permeation, protect drug payload from the harsh environment of the stomach, and explore the ability for targeted drug delivery. However, in order to eventually pave the way for real life applications of these microfabricated drug delivery systems, it is necessary to fabricate them in biodegradable materials approved for similar applications and with strategies that potentially allow for large scale production. In this study, we for the first time evaluate biodegradable microcontainers for oral drug delivery. Asymmetric poly-ε-caprolactone (PCL) microcontainers with a diameter of 300 µm and a volume of 2.7 nL are fabricated with a novel single-step fabrication process. The microcontainers are loaded with the model drug paracetamol and coated with an enteric pH-sensitive Eudragit® S100 coating to protect the drug until it reaches the desired location in the small intestine. In vitro dissolution studies are performed to assess the drug load and release profile of the PCL microcontainers. Finally, in vivo studies in rats showed a higher bioavailability compared to conventional dosage forms and confirm the potential of biodegradable microcontainers for oral drug delivery.


Asunto(s)
Acetaminofén/farmacocinética , Sistemas de Liberación de Medicamentos , Microtecnología , Poliésteres/química , Acetaminofén/administración & dosificación , Acetaminofén/química , Administración Oral , Animales , Liberación de Fármacos , Masculino , Microtecnología/instrumentación , Tamaño de la Partícula , Poliésteres/administración & dosificación , Ratas , Ratas Sprague-Dawley
9.
ACS Biomater Sci Eng ; 5(6): 2935-2941, 2019 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-33405596

RESUMEN

To enhance oral bioavailability of poorly soluble drugs, microfabricated devices can be utilized. One example of such devices is microcontainers. These are cylindrical in shape with an inner cavity for drug loading and with only the top side open for release. Supercritical CO2 (scCO2) impregnation is an interesting technique for loading drugs into polymeric matrices in, for example, microcontainers since it avoids the use of organic solvents and is cheap. One of the main drawbacks of this technique is the unknown three-dimensional drug distribution in the polymer matrix. The aim of this study was to investigate the loading of two poorly soluble drugs, naproxen and ketoprofen, by scCO2 impregnation into confined polymer matrices of different sizes. Three different sizes of microcontainers (small, medium, and large) and, thereby, different surface areas accessible for impregnation were compared. From in vitro studies, the amount of naproxen and ketoprofen loaded into the different microcontainers and their corresponding release profiles were seen to be similar. A custom-made Raman microscope facilitated volumetric Raman maps of an entire microcontainer filled with polyvinylpyrrolidone (PVP) and scCO2 impregnated with either naproxen or ketoprofen. In all microcontainer sizes, the drugs were only detected in the top layer of the polymer matrix, explaining the observed similar release profiles. Using X-ray powder diffraction and Raman spectroscopy, the solid state form of the drugs was evaluated, showing that ketoprofen was amorphous in all microcontainer sizes. Naproxen was found not to be crystalline nor amorphous but in a less ordered configuration than the crystalline state. In conclusion, volumetric Raman mapping is a powerful technology for imaging drug distribution and drug crystallinity in polymers and allowed us to conclude that (i) scCO2 impregnation depth does not depend on surface area and (ii) impregnated drugs are noncrystalline.

10.
Macromol Biosci ; 19(5): e1900004, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-30938933

RESUMEN

Oral delivery of proteins and peptides is one of the main challenges in pharmaceutical drug development. Microdevices have the possibility to protect the therapeutics until release is desired, avoiding losses by degradation. One type of microdevice is polymeric microcontainers. In this study, lysozyme is chosen as model protein and loaded into microcontainers with the permeation enhancer sodium decanoate (C10). The loaded microcontainers are sealed and functionalized by applying polymeric lids onto the cavity of the devices. The first lid is poly(lactic-co-glycolic) acid (PLGA) and on top of this either polyethylene glycol (PEG) or chitosan is applied (PLGA+PEG or PLGA+chitosan, respectively). The functionalization is evaluated in vitro for morphology, drug release, and mucoadhesive properties. These are coupled with in vitro and ex vivo studies using Caco-2 cells, Caco-2/HT29-MTX-E12 co-cultures, and porcine intestinal tissue. PLGA+chitosan shows slower release compared to PLGA+PEG or only PLGA in buffer and the transport of lysozyme across cell cultures is not enhanced compared to the bulk powder. Microcontainers coated with chitosan or PEG demonstrate a three times stronger adhesion during ex vivo mucoadhesion studies compared to samples without coatings. Altogether, functionalized microcontainers with mucoadhesive properties and tunable release for oral protein delivery are developed and characterized.


Asunto(s)
Quitosano , Sistemas de Liberación de Medicamentos , Muramidasa , Polietilenglicoles , Copolímero de Ácido Poliláctico-Ácido Poliglicólico , Administración Oral , Animales , Células CACO-2 , Quitosano/química , Quitosano/farmacocinética , Quitosano/farmacología , Células HT29 , Humanos , Muramidasa/química , Muramidasa/farmacocinética , Muramidasa/farmacología , Polietilenglicoles/química , Polietilenglicoles/farmacocinética , Polietilenglicoles/farmacología , Copolímero de Ácido Poliláctico-Ácido Poliglicólico/química , Copolímero de Ácido Poliláctico-Ácido Poliglicólico/farmacocinética , Copolímero de Ácido Poliláctico-Ácido Poliglicólico/farmacología , Porcinos
11.
J Control Release ; 268: 343-351, 2017 Dec 28.
Artículo en Inglés | MEDLINE | ID: mdl-29054373

RESUMEN

This work explores the potential of polymeric micrometer sized devices (microcontainers) as oral drug delivery systems (DDS). Arrays of detachable microcontainers (D-MCs) were fabricated on a sacrificial layer to improve the handling and facilitate the collection of individual D-MCs. A model drug, ketoprofen, was loaded into the microcontainers using supercritical CO2 impregnation, followed by deposition of an enteric coating to protect the drug from the harsh gastric environment and to provide a fast release in the intestine. In vitro, in vivo and ex vivo studies were performed to assess the viability of the D-MCs as oral DDS. D-MCs improved the relative oral bioavailability by 180% within 4h, and increased the absorption rate by 2.4 times compared to the control. This work represents a significant step forward in the translation of these devices from laboratory to clinic.


Asunto(s)
Sistemas de Liberación de Medicamentos , Administración Oral , Animales , Cápsulas , Ácidos Dicarboxílicos/administración & dosificación , Ácidos Dicarboxílicos/química , Liberación de Fármacos , Mucosa Gástrica/metabolismo , Yeyuno/metabolismo , Cetoprofeno/administración & dosificación , Cetoprofeno/sangre , Cetoprofeno/química , Cetoprofeno/farmacocinética , Masculino , Ácidos Polimetacrílicos/administración & dosificación , Ácidos Polimetacrílicos/química , Povidona/administración & dosificación , Povidona/química , Ratas Sprague-Dawley
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA