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1.
J Environ Manage ; 347: 119128, 2023 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-37778066

RESUMEN

Wastewater containing antibiotics, organic dyes, and waterborne bacteria is a severe threat to human health and the environment. Amoxicillin has a slow metabolism rate in humans. Methylene blue is mutagenic and carcinogenic. In addition, Salmonella causes serious diarrhea. In this study, an effective 2D/2D photocatalyst with excellent elimination of these pollutants was fabricated by combining graphene oxide (GO), Bi2WO6, BiPO4 and Ag species. GO was applied at varying loading contents (0.8, 1.6, 2.4, 3.2 wt%) to improve the properties of the photocatalyst toward the removal of representative pollutants. The chemical structures, morphology, light absorption and charge mobility were investigated by different GO loading samples. The results indicated that when the wt% of GO was 2.4%, the photocatalyst showed excellent photocatalytic properties and removal rates for typical pollutants. Amoxicillin and methylene blue were mineralized into CO2, H2O, and small molecules, while Salmonella was disinfected with excellent photocatalytic efficiency. Furthermore, the possible photodecomposition pathways of amoxicillin and methylene blue were proposed by DFT calculations and intermediates identified by LCMS. The mechanism of the photocatalytic process was investigated by radical trapping experiments, ESR spectroscopy, and Motty-Schottky plots. The free radicals could be produced constantly during the photocatalytic process, leading to mineralization of amoxicillin and methylene blue, and disinfection of Salmonella. In this work, a new perspective on GO modified Bi2WO6 with different loading contents and the degradation pathways of antibiotics and dyes was proposed.


Asunto(s)
Contaminantes Ambientales , Humanos , Azul de Metileno/química , Teoría Funcional de la Densidad , Luz , Antibacterianos , Amoxicilina , Colorantes , Catálisis
2.
Int J Mol Sci ; 23(12)2022 Jun 08.
Artículo en Inglés | MEDLINE | ID: mdl-35742851

RESUMEN

Biomimetic microenvironments are important for controlling stem cell functions. In this study, different microenvironmental conditions were investigated for the stepwise control of proliferation and chondrogenic differentiation of human bone-marrow-derived mesenchymal stem cells (hMSCs). The hMSCs were first cultured in collagen porous sponges and then embedded with or without collagen hydrogels for continual culture under different culture conditions. The different influences of collagen sponges, collagen hydrogels, and induction factors were investigated. The collagen sponges were beneficial for cell proliferation. The collagen sponges also promoted chondrogenic differentiation during culture in chondrogenic medium, which was superior to the effect of collagen sponges embedded with hydrogels without loading of induction factors. However, collagen sponges embedded with collagen hydrogels and loaded with induction factors had the same level of promotive effect on chondrogenic differentiation as collagen sponges during in vitro culture in chondrogenic medium and showed the highest promotive effect during in vivo subcutaneous implantation. The combination of collagen sponges with collagen hydrogels and induction factors could provide a platform for cell proliferation at an early stage and subsequent chondrogenic differentiation at a late stage. The results provide useful information for the chondrogenic differentiation of stem cells and cartilage tissue engineering.


Asunto(s)
Condrogénesis , Células Madre Mesenquimatosas , Diferenciación Celular , Proliferación Celular , Células Cultivadas , Colágeno/farmacología , Humanos , Hidrogeles/farmacología
3.
Int J Mol Sci ; 23(8)2022 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-35457034

RESUMEN

Localization of tumors during laparoscopic surgery is generally performed by locally injecting India ink into the submucosal layer of the gastrointestinal tract using endoscopy. However, the location of the tumor is obscured because of the black-stained surgical field and the blurring caused by India ink. To solve this problem, in this study, we developed a tissue-adhesive porphyrin with polycations consisting of quaternary ammonium salt groups. To evaluate the ability of tissue-adhesive porphyrin in vivo, low-molecular-weight hematoporphyrin and tissue-adhesive porphyrin were injected into the anterior wall of the exposed stomach in rats. Local injection of low-molecular-weight hematoporphyrin into the anterior wall of the stomach was not visible even after 1 day because of its rapid diffusion. In contrast, the red fluorescence of the tissue-adhesive porphyrin was visible even after 7 days due to the electrostatic interactions between the positively-charged moieties of the polycation in the tissue-adhesive porphyrin and the negatively-charged molecules in the tissue. In addition, intraperitoneal injection of tissue-adhesive porphyrin in rats did not cause adverse effects such as weight loss, hepatic or renal dysfunction, or organ adhesion in the abdominal cavity. These results indicate that tissue-adhesive porphyrin is a promising fluorescent tissue-marking agent.


Asunto(s)
Porfirinas , Adhesivos Tisulares , Animales , Colorantes , Hematoporfirinas , Polielectrolitos , Compuestos de Amonio Cuaternario , Ratas
4.
Sci Technol Adv Mater ; 22(1): 404-428, 2021 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-34121928

RESUMEN

Photothermal therapy (PTT) has attracted broad attention as a promising method for cancer therapy with less severe side effects than conventional radiation therapy, chemotherapy and surgical resection. PTT relies on the photoconversion capacity of photothermal agents (PTAs), and a wide variety of nanomaterials have been employed as PTAs for cancer therapy due to their excellent photothermal properties. The PTAs are systematically or locally administered and become enriched in cancer cells to increase ablation efficiency. In recent years, PTAs and three-dimensional scaffolds have been hybridized to realize the local delivery of PTAs for the repeated ablation of cancer cells. Meanwhile, the composite scaffolds can stimulate the reconstruction and regeneration of the functional tissues and organs after ablation of cancer cells. A variety of composite scaffolds of photothermal nanomaterials have been prepared to combine the advantages of different modalities to maximize their therapeutic efficacy with minimal side effects. The synergistic effects make the composite scaffolds attractive for biomedical applications. This review summarizes these latest advances and discusses the future prospects.

5.
Adv Exp Med Biol ; 1250: 141-155, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32601943

RESUMEN

Micro-patterned surfaces have been broadly used to control the morphology of stem cells for investigation of the influence of physiochemical and biological cues on stem cell functions. Different structures of micro-patterned surfaces can be prepared by photolithography through designing the photomask features. Cell spreading area, geometry, aspect ratio, and alignment can be regulated by the micro-patterned structures. Their influences on adipogenic, osteogenic, and smooth muscle differentiation of the human bone marrow-derived mesenchymal stem cells are compared and investigated in details. Variation of cell morphology can trigger rearrangement of cytoskeleton, generating cytoskeletal mechanical stimulation and consequently inducing differentiation of mesenchymal stem cells into different lineages. This chapter summarizes the latest development of regulation of mesenchymal stem cell morphology by micro-patterns and the influence on the behaviors and differentiation of the mesenchymal stem cells.


Asunto(s)
Diferenciación Celular , Células Madre Mesenquimatosas , Linaje de la Célula , Células Cultivadas , Humanos , Células Madre Mesenquimatosas/citología
6.
J Nat Prod ; 81(5): 1290-1294, 2018 05 25.
Artículo en Inglés | MEDLINE | ID: mdl-29715021

RESUMEN

A chemical investigation of the ascomycetes of Daldinia concentrica was performed using silica gel column chromatography, ODS column chromatography, and preparative HPLC. Two new isoindolinone compounds, daldinans B (1) and C (2), two new phthalide compounds, daldinolides A (3) and B (4), and a new naphthoquinone, daldiquinone (5), were isolated together with two known compounds (6 and 7). The structures of 1, 2, and 5 were established using NMR, MS, and IR methods, and the structures of 3 and 4 were determined by derivatization from known compounds (6 and 7). 5 exhibited antiangiogenesis activity against HUVECs (IC50 = 7.5 µM).


Asunto(s)
Ascomicetos/química , Benzofuranos/química , Naftoquinonas/química , Ftalimidas/química , Línea Celular , Cromatografía Líquida de Alta Presión/métodos , Células Endoteliales de la Vena Umbilical Humana , Humanos , Espectroscopía de Resonancia Magnética/métodos
7.
Adv Exp Med Biol ; 1078: 465-474, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30357638

RESUMEN

Extracellular matrix (ECM) interacts with cells and provides important signals to control cell functions and to maintain homeostasis of living organisms. Composition of ECM in each tissue is dependent on cell type and cell phenotype. ECM also dynamically changes its composition during stem cell differentiation and tissue development. Various ECM substrates and scaffolds have been prepared for stem cells culture and tissue engineering. They can be reconstructed by using isolated ECM components or acellular matrices from different tissues and organs. In recent years, cultured cells have been used as a useful source to prepare biomimetic ECM substrates and scaffolds. ECM derived from different cell type can be prepared by culturing the respective cells to allow the cells to secrete desirable ECM components. Furthermore, dynamically changing ECM can be prepared by controlling the stepwise differentiation of stem cells. The composition of the biomimetic ECM substrates and scaffolds changes with cell type and has different effects on differentiation of stem cells. The latest progress on biomimetic ECM substrates and scaffolds derived from cultured cells is summarized and highlighted.


Asunto(s)
Materiales Biomiméticos , Matriz Extracelular , Ingeniería de Tejidos , Andamios del Tejido , Diferenciación Celular , Células Cultivadas , Humanos , Células Madre/citología
8.
Adv Exp Med Biol ; 1058: 171-191, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29691822

RESUMEN

Porous scaffolds play an important role as a temporary support for accommodation of seeded cells to control their functions and guide regeneration of functional tissues and organs. Various scaffolds have been prepared from biodegradable polymers and calcium phosphate. They have also been hybridized with bioactive factors to control differentiation of stem cells. Except the composition, porous structures of scaffolds are also extremely important for cell adhesion, spatial distribution and tissue regeneration. The method using preprepared ice particulates has been developed to precisely control surface and bulk pore structures of porous scaffolds. This chapter summarizes the design and preparation of porous scaffolds of biodegradable polymers and their hybrid scaffolds with calcium phosphate nanoparticles and bioactive factors. Their applications for regeneration of cartilage, bone and osteochondral tissue will be highlighted. HIGHLIGHTS: Porous scaffolds of naturally derived polymers and their hybrid scaffolds with biodegradable synthetic polymers have been prepared for cartilage tissue engineering. The surface and bulk pore structures of the scaffolds are controlled by using preprepared ice particulates. The scaffolds facilitate cartilage tissue engineering when they are used for three-dimension culture of chondrocytes. PLGA-collagen-BMP4 and collagen-CaP nanoparticles-dexamethasone hybrid scaffolds have been prepared and used for culture of mesenchymal stem cells. The hybrid scaffolds facilitate osteogenic differentiation of mesenchymal stem cells and ectopic bone tissue regeneration during in vitro culture and in vivo implantation. Osteochondral tissue engineering has been realized by laminating two different layers of cartilage and subchondral bone or by using stratified scaffolds for simultaneous regeneration of cartilage and subchondral bone.


Asunto(s)
Regeneración Ósea , Huesos , Cartílago , Nanopartículas , Andamios del Tejido/química , Animales , Adhesión Celular , Diferenciación Celular , Humanos , Porosidad , Células Madre/metabolismo
9.
J Nanosci Nanotechnol ; 14(3): 2487-92, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24745252

RESUMEN

Carbon nanotubes (CNTs) exhibit intrinsic unique physical and chemical properties that make them attractive candidates for biological and biomedicine applications. An efficient cellular uptake of CNTs is vital for many of these applications. However, most of the cellular uptake studies have been performed with a two-dimensional cell culture system. In this study, cellular uptake of single-walled carbon nanotubes (SWCNTs) was investigated by using a three-dimensional cell culture system. Bovine articular chondrocytes cultured in SWCNTs/collagen composite hydrogels maintained their proliferation capacity when compared to the culture in collagen hydrogels. Ultraviolet-visible-near-infrared spectroscopy analysis revealed a high amount of SWCNTs were internalized by cells. Confocal Raman imaging showed that most of the internalized SWCNTs were distributed in the perinuclear region. The results indicated that SWCNTs could be internalized by chondrocytes when SWCNTs were incorporated in the three-dimensional biomimetic collagen hydrogels.


Asunto(s)
Cartílago Articular/citología , Colágeno/química , Matriz Extracelular/metabolismo , Hidrogeles/química , Nanotubos de Carbono/química , Animales , Biomimética , Bovinos , Técnicas de Cultivo de Célula , Supervivencia Celular , Células Cultivadas , Condrocitos/citología , Ensayo de Materiales , Propiedades de Superficie
10.
J Nanosci Nanotechnol ; 14(3): 2459-65, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24745247

RESUMEN

It is important to elucidate the effects of carbon nanotubes on cell functions for their biomedical applications. In this study, the effect of single-walled carbon nanotubes (SWCNTs) on the mechanical property of chondrocytes was investigated by atomic force microscopy. Chondrocytes were cultured in medium containing SWCNTs and showed an increase uptake of SWCNTs with culture time. The mechanical property of chondrocytes cultured with or without SWCNTs was measured at an indentation depth of 200 nm and 500 nm. The chondrocytes cultured with SWCNTs showed higher Young's modulus than that of cells cultured without SWCNTs at both indentation depths. The increase became significant after culture for more than 3 hours. Indentation at 500 nm depth magnified the change of Young's modulus compared to that monitored at 200 nm indentation depth. The results indicated uptake of SWCNTs increased the Young's modulus of chondrocytes.


Asunto(s)
Condrocitos/citología , Condrocitos/efectos de los fármacos , Nanotubos de Carbono/química , Animales , Carbono/química , Bovinos , Células Cultivadas , Módulo de Elasticidad , Microscopía de Fuerza Atómica , Tamaño de la Partícula , Estrés Mecánico , Propiedades de Superficie , Factores de Tiempo
11.
J Nanosci Nanotechnol ; 14(4): 3221-7, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24734758

RESUMEN

Porous materials and scaffolds have wide applications in biomedical and biological fields. They can provide biological and physical cues to promote cell adhesion, proliferation, differentiation and extracellular matrix secretion to guide new tissue formation. Hybrid scaffolds of collagen and wollastonite nanowires with well controlled pore structures were prepared by using ice particulates as a porogen material. The hybrid scaffolds had interconnected large spherical pores with wollastonite nanowires embedded in the walls of the pores. The wollastonite nanowires reinforced the hybrid scaffolds and showed some stimulatory effects on cell functions. Human bone marrow-derived mesenchymal stem cells showed higher proliferation and osteogenic differentiation and expressed higher level of genes encoding angiogenesis-related genes in the hybrid scaffolds than did in the collagen scaf-. fold. The results suggest the hybrid scaffolds could facilitate osteogenic differentiation and induce angiogenesis and will be useful for bone tissue engineering.


Asunto(s)
Inductores de la Angiogénesis/metabolismo , Compuestos de Calcio/farmacología , Diferenciación Celular/efectos de los fármacos , Colágeno/farmacología , Células Madre Mesenquimatosas/metabolismo , Nanocables/química , Osteogénesis/efectos de los fármacos , Silicatos/farmacología , Animales , Adhesión Celular/efectos de los fármacos , Diferenciación Celular/genética , Proliferación Celular/efectos de los fármacos , ADN/metabolismo , Módulo de Elasticidad/efectos de los fármacos , Regulación de la Expresión Génica/efectos de los fármacos , Humanos , Células Madre Mesenquimatosas/citología , Células Madre Mesenquimatosas/efectos de los fármacos , Nanocables/ultraestructura , Osteogénesis/genética , Porosidad , Sus scrofa , Andamios del Tejido/química
12.
J Appl Glycosci (1999) ; 71(2): 47-54, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38863952

RESUMEN

Super Ohtaka®, a fermented beverage of plant extracts, is prepared from approximately 50 kinds of fruits and vegetables. Natural fermentation is mainly performed by lactic acid bacteria (Leuconostoc spp.) and yeast (Zygosaccharomyces spp.). Four water-soluble polysaccharide fractions were obtained from Super Ohtaka® by dialysis, ion exchange chromatography, and gel filtration chromatography; these fractions were designated as OEP1-1, OEP1-2, OEP2, and OEP3. OEP1-1 is a polysaccharide composed solely of glucose. The other fractions contained polysaccharides composed of glucose, galactose, mannose, and a small amount of arabinose. OEP2 and OEP3 contained phosphorus, which was not detected in OEP1-1 and OEP1-2. Furthermore, the immunomodulatory activity of the polysaccharides was investigated in murine macrophage cell lines. OEP2 and OEP3 significantly induced nitric oxide (NO) secretion by macrophages in a dose-dependent manner (concentration range of 4 to 100 µg/mL). When the concentration of OEP3 was 100 µg/mL, NO production was almost identical to lipopolysaccharide (LPS; 10 ng/mL) used as a positive control. Notably, OEP3 induced NO secretion more strongly than OEP2. This trend was also observed for TNF-α, IL-1ß, IL-6, and IL-12 p40 secretion. Overall, our in vitro studies on polysaccharides isolated from Super Ohtaka® suggest that the fermented beverage stimulates macrophages and activates the immune system.

13.
Gels ; 10(3)2024 Mar 17.
Artículo en Inglés | MEDLINE | ID: mdl-38534620

RESUMEN

Chemotherapy is one of the most common strategies for cancer treatment, whereas drug resistance reduces the efficiency of chemotherapy and leads to treatment failure. The mechanism of emerging chemoresistance is complex and the effect of extracellular matrix (ECM) surrounding cells may contribute to drug resistance. Although it is well known that ECM plays an important role in orchestrating cell functions, it remains exclusive how ECM stiffness affects drug resistance. In this study, we prepared agarose hydrogels of different stiffnesses to investigate the effect of hydrogel stiffness on the chemoresistance of breast cancer cells to doxorubicin (DOX). Agarose hydrogels with a stiffness range of 1.5 kPa to 112.3 kPa were prepared and used to encapsulate breast cancer cells for a three-dimensional culture with different concentrations of DOX. The viability of the cells cultured in the hydrogels was dependent on both DOX concentration and hydrogel stiffness. Cell viability decreased with DOX concentration when the cells were cultured in the same stiffness hydrogels. When DOX concentration was the same, breast cancer cells showed higher viability in high-stiffness hydrogels than they did in low-stiffness hydrogels. Furthermore, the expression of P-glycoprotein mRNA in high-stiffness hydrogels was higher than that in low-stiffness hydrogels. The results suggested that hydrogel stiffness could affect the resistance of breast cancer cells to DOX by regulating the expression of chemoresistance-related genes.

14.
Acta Biomater ; 182: 81-92, 2024 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-38734287

RESUMEN

Tuning cell adhesion geometry can affect cytoskeleton organization and the distribution of cytoskeleton forces, which play critical roles in controlling cell functions. To elucidate the geometrical relationship with cytoskeleton force distribution, it is necessary to control cell morphology. In this study, a series of dextral vortex micropatterns were prepared to precisely control cell morphology for investigating the influence of the curvature degree of adhesion curves on intracellular force distribution and stem cell differentiation at a sub-cellular level. Peripherial actin filaments of micropatterned cells were assembled along the adhesion curves and showed different orientations, filament thicknesses and densities. Focal adhesion and cytoskeleton force distribution were dependent on the curvature degree. Intracellular force distribution was also regulated by adhesion curves. The cytoskeleton and force distribution affected the osteogenic differentiation of mesenchymal stem cells through a YAP/TAZ-mediated mechanotransduction process. Thus, regulation of cell adhesion curvature, especially at cytoskeletal filament level, is critical for cell function manipulation. STATEMENT OF SIGNIFICANCE: In this study, a series of dextral micro-vortexes were prepared and used for the culture of human mesenchymal stem cells (hMSCs) to precisely control adhesive curvatures (0°, 30°, 60°, and 90°). The single MSCs on the micropatterns had the same size and shape but showed distinct focal adhesion (FA) and cytoskeleton orientations. Cellular nanomechanics were observed to be correlated with the curvature degrees, subsequently influencing nuclear morphological features. As a consequence, the localization of the mechanotransduction sensor and activator-YAP/TAZ was affected, influencing osteogenic differentiation. The results revealed the pivotal role of adhesive curvatures in the manipulation of stem cell differentiation via the machanotransduction process, which has rarely been investigated.


Asunto(s)
Diferenciación Celular , Adhesiones Focales , Mecanotransducción Celular , Células Madre Mesenquimatosas , Osteogénesis , Adhesiones Focales/metabolismo , Células Madre Mesenquimatosas/citología , Células Madre Mesenquimatosas/metabolismo , Mecanotransducción Celular/fisiología , Humanos , Osteogénesis/fisiología , Actinas/metabolismo , Adhesión Celular , Forma de la Célula , Proteínas Señalizadoras YAP
15.
Biomaterials ; 307: 122511, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38401482

RESUMEN

Combination of different therapies is an attractive approach for cancer therapy. However, it is a challenge to synchronize different therapies for maximization of therapeutic effects. In this work, a smart composite scaffold that could synchronize magnetic hyperthermia and chemotherapy was prepared by hybridization of magnetic Fe3O4 nanoparticles and doxorubicin (Dox)-loaded thermosensitive liposomes with biodegradable polymers. Irradiation of alternating magnetic field (AMF) could not only increase the scaffold temperature for magnetic hyperthermia but also trigger the release of Dox for chemotherapy. The two functions of magnetic hyperthermia and chemotherapy were synchronized by switching AMF on and off. The synergistic anticancer effects of the composite scaffold were confirmed by in vitro cell culture and in vivo animal experiments. The composite scaffold could efficiently eliminate breast cancer cells under AMF irradiation. Moreover, the scaffold could support proliferation and adipogenic differentiation of mesenchymal stem cells for adipose tissue reconstruction after anticancer treatment. In vivo regeneration experiments showed that the composite scaffolds could effectively maintain their structural integrity and facilitate the infiltration and proliferation of normal cells within the scaffolds. The composite scaffold possesses multi-functions and is attractive as a novel platform for efficient breast cancer therapy.


Asunto(s)
Doxorrubicina/análogos & derivados , Hipertermia Inducida , Neoplasias , Animales , Línea Celular Tumoral , Doxorrubicina/farmacología , Doxorrubicina/uso terapéutico , Hipertermia , Fenómenos Magnéticos , Polietilenglicoles
16.
Cell Transplant ; 33: 9636897241249556, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38742734

RESUMEN

Pancreatic islet transplantation is one of the clinical options for certain types of diabetes. However, difficulty in maintaining islets prior to transplantation limits the clinical expansion of islet transplantations. Our study introduces a dynamic culture platform developed specifically for primary human islets by mimicking the physiological microenvironment, including tissue fluidics and extracellular matrix support. We engineered the dynamic culture system by incorporating our distinctive microwell-patterned porous collagen scaffolds for loading isolated human islets, enabling vertical medium flow through the scaffolds. The dynamic culture system featured four 12 mm diameter islet culture chambers, each capable of accommodating 500 islet equivalents (IEQ) per chamber. This configuration calculates > five-fold higher seeding density than the conventional islet culture in flasks prior to the clinical transplantations (442 vs 86 IEQ/cm2). We tested our culture platform with three separate batches of human islets isolated from deceased donors for an extended period of 2 weeks, exceeding the limits of conventional culture methods for preserving islet quality. Static cultures served as controls. The computational simulation revealed that the dynamic culture reduced the islet volume exposed to the lethal hypoxia (< 10 mmHg) to ~1/3 of the static culture. Dynamic culture ameliorated the morphological islet degradation in long-term culture and maintained islet viability, with reduced expressions of hypoxia markers. Furthermore, dynamic culture maintained the islet metabolism and insulin-secreting function over static culture in a long-term culture. Collectively, the physiological microenvironment-mimetic culture platform supported the viability and quality of isolated human islets at high-seeding density. Such a platform has a high potential for broad applications in cell therapies and tissue engineering, including extended islet culture prior to clinical islet transplantations and extended culture of stem cell-derived islets for maturation.


Asunto(s)
Colágeno , Islotes Pancreáticos , Andamios del Tejido , Humanos , Islotes Pancreáticos/citología , Islotes Pancreáticos/metabolismo , Andamios del Tejido/química , Porosidad , Técnicas de Cultivo de Célula/métodos , Técnicas de Cultivo de Célula/instrumentación , Trasplante de Islotes Pancreáticos/métodos
17.
ACS Appl Bio Mater ; 6(9): 3441-3450, 2023 09 18.
Artículo en Inglés | MEDLINE | ID: mdl-37061939

RESUMEN

Matrix stiffness has been disclosed as an essential regulator of cell fate. However, it is barely studied how the matrix stiffness affects stem cell functions when cell morphology changes. Thus, in this study, the effect of hydrogel stiffness on adipogenic differentiation of human bone-marrow-derived mesenchymal stem cells (hMSCs) with controlled morphology was investigated. Micropatterns of different size and elongation were prepared by a photolithographical micropatterning technique. The hMSCs were cultured on the micropatterns and showed a different spreading area and elongation following the geometry of the underlying micropatterns. The cells with controlled morphology were embedded in agarose hydrogels of different stiffnesses. The cells showed a different level of adipogenic differentiation that was dependent on both hydrogel stiffness and cell morphology. Adipogenic differentiation became strong when the cell spreading area decreased and hydrogel stiffness increased. Adipogenic differentiation did not change with cell elongation. Therefore, cell spreading area and hydrogel stiffness could synergistically affect adipogenic differentiation of hMSCs, while cell elongation did not affect adipogenic differentiation. A change of cell morphology and hydrogel stiffness was accompanied by actin filament alignment that was strongly related to adipogenic differentiation. The results indicated that cell morphology could affect cellular sensitivity to hydrogel stiffness. The results will provide useful information for the elucidation of the interaction of stem cells and their microenvironmental biomechanical cues.


Asunto(s)
Hidrogeles , Células Madre Mesenquimatosas , Humanos , Hidrogeles/farmacología , Diferenciación Celular , Células Cultivadas , Proliferación Celular
18.
J Mater Chem B ; 11(31): 7424-7434, 2023 08 09.
Artículo en Inglés | MEDLINE | ID: mdl-37431770

RESUMEN

The mechanical properties of an extracellular microenvironment can affect cell functions. The effects of elasticity and viscoelasticity on cell functions have been extensively studied with hydrogels of tunable mechanical properties. However, investigation of the viscosity effect on cell functions is still very limited and it can be tricky to explore how viscosity affects cells in three-dimensional (3D) culture due to the lack of appropriate tools. In this study, agarose hydrogel containers were prepared and used to encapsulate viscous media for 3D cell culture to investigate the viscosity effect on the functions of bovine articular chondrocytes (BACs). Polyethylene glycol of different molecular weights was used to adjust culture medium viscosity in a large range (72.8-679.2 mPa s). The viscosity affected gene expression and secretion of cartilagenious matrices, while it did not affect BAC proliferation. The BACs cultured in the lower viscosity medium (72.8 mPa s) showed a higher level of cartilaginous gene expression and matrix secretion.


Asunto(s)
Condrocitos , Hidrogeles , Animales , Bovinos , Hidrogeles/farmacología , Sefarosa , Viscosidad , Cartílago
19.
Free Radic Biol Med ; 207: 239-246, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37499887

RESUMEN

Recently, plasma membrane-targeted photodynamic therapy has attracted attention as an effective cancer immunotherapeutic strategy. However, the released photosensitizers do not only adhere to the plasma membrane but may also be internalized in the cytosol, in endosomes/lysosomes, hindering investigations of the effects of photosensitizers attached to the plasma membrane. In this study, we developed a cell culture dish with singlet oxygen-generating cell-adhesive glass surfaces that allows investigation of the effects of photosensitizers attached to the plasma membrane. For cell adhesion, poly[N-(3-aminopropyl)methacrylamide] conjugated with hematoporphyrin PA-HpD was immobilized on the glass surfaces. Singlet oxygen was produced from the PA-HpD-immobilized glass surface upon laser irradiation at 635 nm. When murine colon adenocarcinoma 26 (Colon-26) cells were cultured on the PA-HpD-immobilized surface, the cells were swollen and ruptured, leading to effective apoptotic cell death using laser irradiation at 635 nm. In addition, microvesicles of approximately 10 µm in diameter were released from the plasma membrane into the culture medium. These phenomena were due to the oxidation of lipids in the cellular membrane, caused by the plasma membrane-targeted photodynamic therapy. In contrast, these phenomena were not observed on poly[N-(3-aminopropyl)methacrylamide]-immobilized glass surfaces. These results indicate that cell culture dishes with singlet oxygen-generating cell-adhesive glass surfaces can be used to investigate fundamental mechanisms in plasma membrane-targeted photodynamic therapy.


Asunto(s)
Adenocarcinoma , Neoplasias del Colon , Fotoquimioterapia , Ratones , Humanos , Animales , Fármacos Fotosensibilizantes/farmacología , Oxígeno Singlete , Membrana Celular
20.
Adv Healthc Mater ; 12(9): e2202604, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36534783

RESUMEN

Postsurgical treatment of breast cancer remains a challenge with regard to killing residual cancer cells and regenerating breast defects. To prepare composite scaffolds for postoperative use, gelatin is chemically modified with folic acid (FA) and used for hybridization with citrate-modified Fe3 O4 nanoparticles (Fe3 O4 -citrate NPs) to fabricate Fe3 O4 /gelatin composite scaffolds which pore structures are controlled by free ice microparticles. The composite scaffolds have large spherical pores that are interconnected to facilitate cell entry and exit. The FA-functionalized composite scaffolds have the ability to capture breast cancer cells. The Fe3 O4 /gelatin composite scaffolds possess a high capacity for magnetic-thermal conversion to ablate breast cancer cells during alternating magnetic field (AMF) irradiation. In addition, the composite scaffolds facilitate the growth and adipogenesis of mesenchymal stem cells. The composite scaffolds have multiple functions for eradication of residual cancer cells under AMF irradiation and for regeneration of resected adipose tissue when AMF is off.


Asunto(s)
Neoplasias de la Mama , Hipertermia Inducida , Nanopartículas , Humanos , Femenino , Gelatina , Neoplasias de la Mama/terapia , Neoplasia Residual , Nanopartículas/química , Fenómenos Magnéticos , Andamios del Tejido
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