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1.
Regen Ther ; 23: 84-93, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37122358

RESUMEN

Introduction: There has been an increasing desire for the development of predictive periodontal regenerative therapy for severe periodontitis. In this study, we investigated the effect of the combined use of fibroblast growth factor-2 (FGF-2), a drug for periodontal regeneration approved in Japan, and carbonated apatite (CO3Ap), bioresorbable and osteoconductive scaffold, on periodontal regeneration in beagle dog model of one-wall periodontal defect (severe intraosseous defect) for 24 weeks in comparison with CO3Ap or vehicle alone. Methods: One-wall periodontal defects were created (mesiodistal width × depth: 4 × 4 mm) on the mesial portion of the mandibular first molar (M1) of beagle dogs on both side. Mixture of FGF-2 and CO3Ap, vehicle and CO3Ap, or vehicle alone were administered to the defects and designated as groups FGF-2+CO3Ap, CO3Ap, and control, respectively. To assess the periodontal regeneration, radiographic analysis over time for 24 weeks, and micro computed tomography (µCT) and histological evaluation at 6 and 24 weeks were performed. Results: For the regenerated tissue in the defect site, the mineral content of the FGF-2+CO3Ap group was higher than that of the CO3Ap group in the radiographic analysis at 6-24 weeks. In the context of new bone formation and replacement, the FGF-2+CO3Ap group exhibited significantly greater new bone volume and smaller CO3Ap volume than the CO3Ap group in the µCT analysis at 6 and 24 weeks. Furthermore, the density of the new bone in the FGF-2+CO3Ap group at 24 weeks was similar to those in the control and CO3Ap groups. Histological evaluation revealed that the length of the new periodontal ligament and cementum in the FGF-2+CO3Ap group was greater than that in the CO3Ap group at 6 weeks. We also examined the effect of the combined use of the FGF-2 and CO3Ap on the existing bone adjacent to the defect and demonstrated that the existing bone height and volume in the FGF-2+CO3Ap group remained significantly greater than those in the CO3Ap group. Conclusion: This study demonstrated that the combination of FGF-2 and CO3Ap was effective not only in enhancing new bone formation and replacing scaffold but also in maintaining the existing bone adjacent to the defect site in a beagle dog model of one-wall periodontal defect. Additionally, new periodontal tissues induced by FGF-2 and CO3Ap may follow a maturation process similar to that formed by spontaneous healing. This suggests that the combined use of FGF-2 and CO3Ap would promote periodontal regeneration in severe bony defects of periodontitis patient.

2.
Nat Commun ; 10(1): 2946, 2019 07 03.
Artículo en Inglés | MEDLINE | ID: mdl-31270421

RESUMEN

The capability to encapsulate designated live cells into a biologically and mechanically tunable polymer layer is in high demand. Here, an approach to weave functional DNA polymer cocoons has been proposed as an encapsulation method. By developing in situ DNA-oriented polymerization (isDOP), we demonstrate a localized, programmable, and biocompatible encapsulation approach to graft DNA polymers onto live cells. Further guided by two mutually aided enzymatic reactions, the grafted DNA polymers are assembled into DNA polymer cocoons at the cell surface. Therefore, the coating of bacteria, yeast, and mammalian cells has been achieved. The capabilities of this approach may offer significant opportunities to engineer cell surfaces and enable the precise manipulation of the encapsulated cells, such as encoding, handling, and sorting, for many biomedical applications.


Asunto(s)
Células Inmovilizadas/citología , ADN/química , Polímeros/química , Membrana Celular/metabolismo , Supervivencia Celular , Células Inmovilizadas/metabolismo , Humanos , Células MCF-7 , Polimerizacion
3.
Sensors (Basel) ; 18(1)2018 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-29361775

RESUMEN

Alizarin red S (ARS) was confined in layer-by-layer (LbL) films composed of phenylboronic acid-modified poly(ethyleneimine) (PBA-PEI) and carboxymethylcellulose (CMC) to study the voltammetric response to diol and polyol compounds. The LbL film-coated gold (Au) electrode and quartz slide were immersed in an ARS solution to uptake ARS into the film. UV-visible absorption spectra of ARS-confined LbL film suggested that ARS formed boronate ester (ARS-PBS) in the film. The cyclic voltammetry of the ARS-confined LbL film-coated electrodes exhibited oxidation peaks at -0.50 and -0.62 V, which were ascribed to the oxidation reactions of ARS-PBS and free ARS, respectively, in the LbL film. The peak current at -0.62 V increased upon the addition of diol or polyol compounds such as L-dopa, glucose, and sorbitol into the solution, depending on the concentration, whereas the peak current at -0.50 V decreased. The results suggest a possible use of ARS-confined PBA-PEI/CMC LbL film-coated Au electrodes for the construction of voltammetric sensors for diol and polyol compounds.

4.
Polymers (Basel) ; 10(2)2018 Jan 29.
Artículo en Inglés | MEDLINE | ID: mdl-30966166

RESUMEN

This review provides an overview of the synthesis of layer-by-layer (LbL) assemblies containing calix[n]arene (CA[n]) and cucurbit[n]uril (CB[n]) and their applications. LbL assemblies, such as thin films and microcapsules, containing selective binding sites have attracted considerable attention because of their potential use in separation and purification, sensors for ions and molecules, and controlled release. CA[n]-containing LbL films have been prepared using sulfonated CA[n] and cationic polymers to construct chemical sensors and molecular containers. CA[n]-containing LbL films deposited on the surface of a porous support are useful as ion-selective membranes that exhibit selective permeability to monovalent ions over multivalent ions. CB[n]s have been used as molecular glues for the construction of LbL films and microcapsules by taking advantage of the strong affinity of CB[n]s to aromatic compounds. CB[n]s form a stable 1:1:1 ternary complex with electron-rich and electron-deficient molecules in LbL films to stabilize the assemblies. CB[n]-containing LbL films can also be deposited on the surfaces of micro templates and nanopore membranes to construct microcapsules for controlled release and nanochannels for selective ion transport, respectively.

5.
J Colloid Interface Sci ; 510: 302-307, 2018 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-28957746

RESUMEN

Multilayer films that decompose in the presence of lactate were prepared by depositing phenylboronic acid-modified poly(allylamine) (PBA-PAH) and poly(vinyl alcohol) (PVA) on a lactate oxidase (LOx) layer. The layers adhered through boronate ester bonds. The resulting LOx(PBA-AH/PVA)10 film was stable in pH 7.4 solution but decomposed following the addition of lactate. The carbon-boron bonds in PBA residues were cleaved by oxidative reaction with H2O2 produced by the enzymatic reaction of LOx. Approximately 90% of the film decomposed following exposure for 120 and 30min to 0.05 and 20mM lactate at pH 7.4, respectively. The multilayer film therefore decomposed under conditions comparable to the extracellular environment of tumors (20mM lactate at pH 6.5). Our results show that LOx/(PBA-PAH/PVA)10 multilayer film could be used for cancer drug delivery systems.


Asunto(s)
Ácidos Borónicos/química , Portadores de Fármacos/química , Ácido Láctico/química , Poliaminas/química , Alcohol Polivinílico/química , Humanos , Concentración de Iones de Hidrógeno , Membranas Artificiales , Oxigenasas de Función Mixta/química , Neoplasias/metabolismo , Oxidación-Reducción , Propiedades de Superficie
6.
Anal Chem ; 89(20): 10776-10782, 2017 10 17.
Artículo en Inglés | MEDLINE | ID: mdl-28930447

RESUMEN

Quantitation of plasma membrane proteins (PMPs) is fundamental and frequently performed daily in the lab. However, challenged by the inherent/interacting heterostructures and complex surroundings of the PMPs in lipid membrane, quantitative techniques for PMP often require complex treatments (e.g., labeling, isolation, purification, and determination), and the sensitivity is usually not satisfactory. To address this problem, we have proposed a novel method that enables quantitation of PMPs with extremely high sensitivity, in an easier-to-manipulate and more streamlined way. This method is based on the design of an in situ rolling cycling replication-templated amplification strategy (isRTA). In fact, two rounds of DNA cascade isothermal amplifications have been conducted. The first round of amplification can provide templates for the second round of amplification; thus, significant enhancement of quantitative signals can be achieved. In this way, PMPs are quantified with ultrahigh sensitivity; as few as 25 copies of PMPs can be detected per cell. Moreover, the advantages of isRTA have been demonstrated by simultaneous identification of several PMP biomarkers (MUC1, EpCAM, and HER2) that are expressed over a wide distribution range on breast cancer cells. The precise typing of breast cancer cell subsets is thus possible because of the "quantitative-to-qualitative" strategy. Therefore, the unprecedented sensitivity and high usability of the isRTA method may present significant prospects for delving into membrane proteins and their related biofunctions in many research fields.


Asunto(s)
ADN/metabolismo , Proteínas de la Membrana/análisis , Técnicas de Amplificación de Ácido Nucleico/métodos , Aptámeros de Nucleótidos/química , Aptámeros de Nucleótidos/metabolismo , Biomarcadores de Tumor/análisis , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/metabolismo , Línea Celular Tumoral , Cartilla de ADN/metabolismo , Molécula de Adhesión Celular Epitelial/análisis , Molécula de Adhesión Celular Epitelial/genética , Molécula de Adhesión Celular Epitelial/metabolismo , Humanos , Proteínas de la Membrana/genética , Proteínas de la Membrana/metabolismo , Microscopía Confocal , Mucina-1/análisis , Mucina-1/genética , Mucina-1/metabolismo , Receptor ErbB-2/análisis , Receptor ErbB-2/genética , Receptor ErbB-2/metabolismo
7.
Materials (Basel) ; 10(6)2017 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-28772942

RESUMEN

The preparation of redox-active coatings is a key step in fabricating electrochemical biosensors. To this goal, a variety of coating materials have been used in combination with redox-active compounds. In this study, alizarin red S (ARS) was confined in layer-by-layer (LbL) films composed of poly(ethyleneimine) (PEI) and carboxymethylcellulose (CMC) to study the redox properties. A gold (Au) disc electrode coated with PEI/CMC LbL film was immersed in an ARS solution to uptake ARS into the film. ARS was successfully confined in the LbL film through electrostatic interactions. The cyclic voltammogram (CV) of ARS-confined PEI/CMC film-coated electrodes thus prepared exhibited redox waves in the potential range from -0.5 to -0.7 V originating from 9,10-anthraquinone moiety in ARS, demonstrating that ARS preserves its redox activity in the LbL film. An additional oxidation peak appeared around -0.4 V in the CV recorded in the solution containing phenylboronic acid (PBA), due to the formation of a boronate ester of ARS (ARS-PBA) in the film. The oxidation peak current at -0.4 V decreased upon addition of 3,4-dihydroxyphenylalanine (L-dopa) to the solution. Thus, the results suggest a potential use of the ARS-confined PEI/CMC films for constructing voltammetric sensors for L-dopa.

8.
Molecules ; 22(7)2017 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-28672780

RESUMEN

This article reviews recent progress in the development of nanomaterial-based electrochemical biosensors for cancer biomarkers. Because of their high electrical conductivity, high affinity to biomolecules, and high surface area-to-weight ratios, nanomaterials, including metal nanoparticles, carbon nanotubes, and graphene, have been used for fabricating electrochemical biosensors. Electrodes are often coated with nanomaterials to increase the effective surface area of the electrodes and immobilize a large number of biomolecules such as enzymes and antibodies. Alternatively, nanomaterials are used as signaling labels for increasing the output signals of cancer biomarker sensors, in which nanomaterials are conjugated with secondary antibodies and redox compounds. According to this strategy, a variety of biosensors have been developed for detecting cancer biomarkers. Recent studies show that using nanomaterials is highly advantageous in preparing high-performance biosensors for detecting lower levels of cancer biomarkers. This review focuses mainly on the protocols for using nanomaterials to construct cancer biomarker sensors and the performance characteristics of the sensors. Recent trends in the development of cancer biomarker sensors are discussed according to the nanomaterials used.


Asunto(s)
Biomarcadores de Tumor/análisis , Técnicas Biosensibles/métodos , Nanoestructuras/química , Técnicas Electroquímicas , Electrodos , Grafito/química , Humanos , Nanopartículas del Metal/química , Nanotubos de Carbono/química
9.
Polymers (Basel) ; 9(11)2017 Oct 25.
Artículo en Inglés | MEDLINE | ID: mdl-30965853

RESUMEN

This review provides an overview of the syntheses of photosensitive layer-by-layer (LbL) films and microcapsules modified with azobenzene derivatives and their biomedical applications. Photosensitive LbL films and microcapsules can be prepared by alternate deposition of azobenzene-bearing polymers and counter polymers on the surface of flat substrates and microparticles, respectively. Azobenzene residues in the films and microcapsules exhibit trans-to-cis photoisomerization under UV light, which causes changes in the physical or chemical properties of the LbL assemblies. Therefore, azobenzene-functionalized LbL films and microcapsules have been used for the construction of photosensitive biomedical devices. For instance, cell adhesion on the surface of a solid can be controlled by UV light irradiation by coating the surface with azobenzene-containing LbL films. In another example, the ion permeability of porous materials coated with LbL films can be regulated by UV light irradiation. Furthermore, azobenzene-containing LbL films and microcapsules have been used as carriers for drug delivery systems sensitive to light. UV light irradiation triggers permeability changes in the LbL films and/or decomposition of the microcapsules, which results in the release of encapsulated drugs and proteins.

10.
Polymers (Basel) ; 9(6)2017 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-30970879

RESUMEN

Recent progress in the development of phenylboronic acid (PBA)-functionalized layer-by-layer (LbL) assemblies and their biomedical applications was reviewed. Stimuli-sensitive LbL films and microcapsules that exhibit permeability changes or decompose in response to sugars and hydrogen peroxide (H2O2) have been developed using PBA-bearing polymers. The responses of PBA-modified LbL assemblies arise from the competitive binding of sugars to PBA in the films or oxidative decomposition of PBA by H2O2. Electrochemical glucose sensors have been fabricated by coating the surfaces of electrodes by PBA-modified LbL films, while colorimetric and fluorescence sensors can be prepared by modifying LbL films with boronic acid-modified dyes. In addition, PBA-modified LbL films and microcapsules have successfully been used in the construction of drug delivery systems (DDS). Among them, much effort has been devoted to the glucose-triggered insulin delivery systems, which are constructed by encapsulating insulin in PBA-modified LbL films and microcapsules. Insulin is released from the PBA-modified LbL assemblies upon the addition of glucose resulting from changes in the permeability of the films or decomposition of the film entity. Research into insulin DDS is currently focused on the development of high-performance devices that release insulin in response to diabetic levels of glucose (>10 mM) but remain stable at normal levels (~5 mM) under physiological conditions.

11.
Mater Sci Eng C Mater Biol Appl ; 72: 118-122, 2017 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-28024567

RESUMEN

Multilayer thin films composed of poly(vinyl alcohol) (PVA) and phenylboronic acid-bearing poly(amidoamine) dendrimer (PBA-PAMAM) were used as a sacrificial layer for constructing freestanding polyelectrolyte films consisting of poly(styrenesulfonate) (PSS) and poly(allylamine hydrochloride) (PAH). Freestanding (PSS/PAH)15 films were successfully released from substrate by exposing composite (PVA/PBA-PAMAM)n/(PSS/PAH)15 films (n=5 and 10) to sorbitol solutions under mild conditions at pH7.0-9.0. The film release was accelerated in solutions of higher sorbitol concentrations at pH9.0 as well as in solutions with lower concentration of NaCl. The results were rationalized based on the scission of boronate ester bonds between PBA-PAMAM and PVA in the (PVA/PBA-PAMAM)n layer due to a competitive binding of sorbitol to PBA-PAMAM.


Asunto(s)
Dendrímeros/química , Sorbitol/química , Ácidos Borónicos/química , Concentración de Iones de Hidrógeno , Microscopía de Fuerza Atómica , Poliaminas/química , Polielectrolitos/química , Poliestirenos/química , Alcohol Polivinílico/química , Cloruro de Sodio/química , Espectrofotometría Ultravioleta
12.
Sensors (Basel) ; 16(12)2016 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-27916961

RESUMEN

This review provides an overview of recent progress in the development of electrochemical biosensors for glycoproteins. Electrochemical glycoprotein sensors are constructed by combining metal and carbon electrodes with glycoprotein-selective binding elements including antibodies, lectin, phenylboronic acid and molecularly imprinted polymers. A recent trend in the preparation of glycoprotein sensors is the successful use of nanomaterials such as graphene, carbon nanotube, and metal nanoparticles. These nanomaterials are extremely useful for improving the sensitivity of glycoprotein sensors. This review focuses mainly on the protocols for the preparation of glycoprotein sensors and the materials used. Recent improvements in glycoprotein sensors are discussed by grouping the sensors into several categories based on the materials used as recognition elements.


Asunto(s)
Técnicas Biosensibles/métodos , Técnicas Electroquímicas/métodos , Glicoproteínas/análisis , Ácidos Borónicos/química , Impresión Molecular , Nanoestructuras/química
13.
PLoS One ; 11(7): e0158485, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27391131

RESUMEN

The long-term stability and qualitative characteristics of periodontium regenerated by FGF-2 treatment were compared with normal physiological healing tissue controls in a Beagle dog 2-wall periodontal defect model 13 months after treatment by assessing tissue histology and three-dimensional microstructure using micro-computed tomography (µCT). After FGF-2 (0.3%) or vehicle treatment at the defect sites, serial changes in the bone mineral content (BMC) were observed using periodic X-ray imaging. Tissues were harvested at 13 months, evaluated histomorphometrically, and the cortical bone volume and trabecular bone structure of the newly formed bone were analyzed using µCT. FGF-2 significantly increased the BMC of the defect area at 2 months compared with that of the control group, and this difference was unchanged through 13 months. The cortical bone volume was significantly increased by FGF-2, but there was no difference between the groups in trabecular bone structure. Bone maturation was occurring in both groups because of the lower cortical volume and denser trabecular bone than what is found in intact bone. FGF-2 also increased the area of newly formed bone as assessed histomorphometrically, but the ratios of trabecular bone in the defect area were similar between the control and FGF-2 groups. These results suggest that FGF-2 stimulates neogenesis of alveolar bone that is of similar quality to that of the control group. The lengths of the regenerated periodontal ligament and cementum, measured as the distance from the defect bottom to the apical end of the gingival epithelium, and height and area of the newly formed bone in the FGF-2 group were larger than those in the control group. The present study demonstrated that, within the limitation of artificial periodontal defect model, the periodontal tissue regenerated by FGF-2 was maintained for 13 months after treatment and was qualitatively equivalent to that generated through the physiological healing process.


Asunto(s)
Factor 2 de Crecimiento de Fibroblastos/farmacología , Enfermedades Mandibulares/metabolismo , Ligamento Periodontal/efectos de los fármacos , Periodoncio/efectos de los fármacos , Periodoncio/patología , Animales , Densidad Ósea/fisiología , Huesos/efectos de los fármacos , Huesos/patología , Perros , Femenino , Enfermedades Mandibulares/etiología
14.
Mater Sci Eng C Mater Biol Appl ; 67: 737-746, 2016 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-27287174

RESUMEN

This review provides an overview of recent progress made in the development of electrochemical biosensors based on phenylboronic acid (PBA) and its derivatives. PBAs are known to selectively bind 1,2- and 1,3-diols to form negatively charged boronate esters in neutral aqueous media and have been used to construct electrochemical glucose sensors because of this selective binding. PBA-modified metal and carbon electrodes have been widely studied as voltammetric and potentiometric glucose sensors. In some cases, ferroceneboronic acid or ferrocene-modified phenylboronic acids are used as sugar-selective redox compounds. Another option for sensors using PBA-modified electrodes is potentiometric detection, in which the changes in surface potential of the electrodes are detected as an output signal. An ion-sensitive field effect transistor (FET) has been used as a signal transducer in potentiometric sensors. Glycoproteins, such as glycated hemoglobin (HbA1c), avidin, and serum albumin can also be detected by PBA-modified electrodes because they contain hydrocarbon chains on the surface. HbA1c sensors are promising alternatives to enzyme-based glucose sensors for monitoring blood glucose levels over the preceding 2-3months. In addition, PBA-modified electrodes can be used to detect a variety of compounds including hydroxy acids and fluoride (F(-)) ions. PBA-based F(-) ion sensors may be useful if reagentless sensors can be developed.


Asunto(s)
Técnicas Biosensibles/métodos , Ácidos Borónicos/análisis , Técnicas Electroquímicas/métodos , Animales , Técnicas Biosensibles/tendencias , Técnicas Electroquímicas/tendencias , Humanos
15.
Artículo en Japonés | MEDLINE | ID: mdl-27212594

RESUMEN

Type B acute aortic dissection (AAD) spares the ascending aorta and is optimally managed by medical therapy in the absence of complications. However, patients with enhanced inflammation sometimes present with aortic enlargement, thereby facing undesirable outcomes. Thus, a better understanding of the molecular and cellular mechanisms involved in AAD-associated inflammatory processes and the requirement for a novel therapeutic approach for patients with type B AAD are unmet clinical needs. This study showed that dissection per se induced neutrophil-chemoattractant chemokine expression in the aortic tunica adventitia, possibly by mechanical injury and stretching followed by pseudolumen formation. Subsequent systemic changes in chemokine-dependent signaling caused neutrophilia and massive neutrophil accumulation in the dissected aorta, thereby leading to aortic enlargement and rupture via interleukin-6 production. Importantly, temporal and spatial dynamics of inflammatory cytokine and chemokine elevation, as well as leukocyte recruitment, were consistent between rodents and humans. Our study provides a new mechanistic insight into neutrophil-mediated adventitial inflammation after AAD and implicates CXCR2- or interleukin-6 neutralization as novel therapeutic strategies to prevent large-artery complications, including aneurysm formation and rupture, in patients with type B AAD.


Asunto(s)
Aorta/metabolismo , Aorta/patología , Aneurisma de la Aorta/complicaciones , Aneurisma de la Aorta/genética , Disección Aórtica/complicaciones , Disección Aórtica/genética , Quimiocinas/genética , Quimiocinas/metabolismo , Expresión Génica , Enfermedades del Sistema Inmune/patología , Interleucina-8/genética , Interleucina-8/metabolismo , Trastornos Leucocíticos/patología , Neutrófilos/patología , Síndrome de Respuesta Inflamatoria Sistémica/etiología , Síndrome de Respuesta Inflamatoria Sistémica/genética , Enfermedad Aguda , Disección Aórtica/prevención & control , Angiotensina II , Animales , Aneurisma de la Aorta/prevención & control , Humanos , Enfermedades del Sistema Inmune/genética , Interleucina-6/metabolismo , Trastornos Leucocíticos/genética , Ratones , Terapia Molecular Dirigida , Receptores de Interleucina-8B/metabolismo , Síndrome de Respuesta Inflamatoria Sistémica/prevención & control
16.
Sci Rep ; 6: 25362, 2016 05 03.
Artículo en Inglés | MEDLINE | ID: mdl-27140831

RESUMEN

Diseases such as cancer arise from systematical reconfiguration of interactions of exceedingly large numbers of proteins in cell signaling. The study of such complicated molecular mechanisms requires multiplexed detection of the inter-connected activities of several proteins in a disease-associated context. However, the existing methods are generally not well-equipped for this kind of application. Here a method for analyzing functionally linked protein activities is developed based on enzyme controlled pairing between complementary peptide helix strands, which simultaneously enables elaborate regulation of catalytic activity of the paired peptides. This method has been used to detect three different types of protein modification enzymes that participate in the modification of extracellular matrix and the formation of invasion front in tumour. In detecting breast cancer tissue samples using this method, up-regulated activity can be observed for two of the assessed enzymes, while the third enzyme is found to have a subtle fluctuation of activity. These results may point to the application of this method in evaluating prometastatic activities of proteins in tumour.


Asunto(s)
Neoplasias de la Mama/patología , Neoplasias de la Mama/secundario , Péptidos/metabolismo , Mapeo de Interacción de Proteínas/métodos , Mapas de Interacción de Proteínas , Líquido Extracelular/química , Femenino , Humanos
17.
Mater Sci Eng C Mater Biol Appl ; 62: 474-9, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-26952449

RESUMEN

Multilayer thin films composed of phenylboronic acid (PBA)-modified poly(allylamine hydrochloride) (PAH), PBA-PAH, with different PBA contents were prepared to study the effect of PBA content on the stability of the films. An alternate deposition of PBA-PAH and poly(vinyl alcohol) (PVA) on the surface of a quartz slide afforded multilayer films through forming boronate ester bonds between PBA-PAH and PVA. The 10-layered (PBA-PAH/PVA)10 films constructed using PBA-PAHs containing 16% and 26% PBA residues were stable in aqueous solutions over the range of pH 4.0-10.0, whereas the multilayer films composed of PBA-PAHs with 5.9% and 8.3% PBA decomposed at pH 8.0 or lower. The pH-sensitive decomposition of the films was rationalized based on the destabilization of the boronate ester bonds in neutral and acidic solutions. In addition, the (PBA-PAH/PVA)10 films decomposed in glucose and fructose solutions as a result of competitive binding of sugars to PBA-PAH in the films. The sugar response of the films depended on the PBA content in PBA-PAH. The (PBA-PAH/PVA)10 films consisting of 16% and 26% PBA-substituted PBA-PAHs are sensitive to physiological relevant level of glucose at pH7.4 while stable in glucose-free solution, suggesting a potential use of the films in constructing glucose-induced delivery systems.


Asunto(s)
Ácidos Borónicos/química , Carbohidratos/química , Membranas Artificiales , Poliaminas/química , Alcohol Polivinílico/química , Concentración de Iones de Hidrógeno
18.
J Am Soc Nephrol ; 27(7): 1925-32, 2016 07.
Artículo en Inglés | MEDLINE | ID: mdl-26609120

RESUMEN

Mitochondrial dysfunction causes increased oxidative stress and depletion of ATP, which are involved in the etiology of a variety of renal diseases, such as CKD, AKI, and steroid-resistant nephrotic syndrome. Antioxidant therapies are being investigated, but clinical outcomes have yet to be determined. Recently, we reported that a newly synthesized indole derivative, mitochonic acid 5 (MA-5), increases cellular ATP level and survival of fibroblasts from patients with mitochondrial disease. MA-5 modulates mitochondrial ATP synthesis independently of oxidative phosphorylation and the electron transport chain. Here, we further investigated the mechanism of action for MA-5. Administration of MA-5 to an ischemia-reperfusion injury model and a cisplatin-induced nephropathy model improved renal function. In in vitro bioenergetic studies, MA-5 facilitated ATP production and reduced the level of mitochondrial reactive oxygen species (ROS) without affecting activity of mitochondrial complexes I-IV. Additional assays revealed that MA-5 targets the mitochondrial protein mitofilin at the crista junction of the inner membrane. In Hep3B cells, overexpression of mitofilin increased the basal ATP level, and treatment with MA-5 amplified this effect. In a unique mitochondrial disease model (Mitomice with mitochondrial DNA deletion that mimics typical human mitochondrial disease phenotype), MA-5 improved the reduced cardiac and renal mitochondrial respiration and seemed to prolong survival, although statistical analysis of survival times could not be conducted. These results suggest that MA-5 functions in a manner differing from that of antioxidant therapy and could be a novel therapeutic drug for the treatment of cardiac and renal diseases associated with mitochondrial dysfunction.


Asunto(s)
Ácidos Indolacéticos/farmacología , Túbulos Renales/citología , Mitocondrias/metabolismo , Miocitos Cardíacos/efectos de los fármacos , Miocitos del Músculo Liso/efectos de los fármacos , Fenilbutiratos/farmacología , Animales , Masculino , Ratones , Ratones Endogámicos C57BL
19.
Materials (Basel) ; 9(6)2016 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-28773548

RESUMEN

Layer-by-layer films composed of polysaccharides and poly(amidoamine) dendrimer bearing phenylboronic acid (PBA-PAMAM) were prepared to study the deposition behavior of the films and their stability in buffer solutions and in sugar solutions. Alginic acid (AGA) and carboxymethylcellulose (CMC) were employed as counter-polymers in constructing LbL films. AGA/PBA-PAMAM films were successfully prepared at pH 6.0-9.0, whereas the preparation of CMC/PBA-PAMAM film was unsuccessful at pH 8.0 and 9.0. The results show that the LbL films formed mainly through electrostatic affinity between PBA-PAMAM and polysaccharides, while, for AGA/PBA-PAMAM films, the participation of boronate ester bonds in the films was suggested. AGA/PBA-PAMAM films were stable in the solutions of pH 6.0-9.0. In contrast, CMC/PBA-PAMAM films decomposed at pH 7.5-9.0. The AGA/PBA-PAMAM films decomposed in response to 5-30 mM fructose at pH 7.5, while the films were stable in glucose solutions. Thus, AGA is useful as a counter-polymer for constructing PBA-PAMAM films that are stable at physiological pH and decompose in response to fructose.

20.
PLoS One ; 10(6): e0131870, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26120833

RESUMEN

Fibroblast growth factor-2 (FGF-2) enhances the formation of new alveolar bone, cementum, and periodontal ligament (PDL) in periodontal defect models. However, the mechanism through which FGF-2 acts in periodontal regeneration in vivo has not been fully clarified yet. To reveal the action mechanism, the formation of regenerated tissue and gene expression at the early phase were analyzed in a beagle dog 3-wall periodontal defect model. FGF-2 (0.3%) or the vehicle (hydroxypropyl cellulose) only were topically applied to the defect in FGF-2 and control groups, respectively. Then, the amount of regenerated tissues and the number of proliferating cells at 3, 7, 14, and 28 days and the number of blood vessels at 7 days were quantitated histologically. Additionally, the expression of osteogenic genes in the regenerated tissue was evaluated by real-time PCR at 7 and 14 days. Compared with the control, cell proliferation around the existing bone and PDL, connective tissue formation on the root surface, and new bone formation in the defect at 7 days were significantly promoted by FGF-2. Additionally, the number of blood vessels at 7 days was increased by FGF-2 treatment. At 28 days, new cementum and PDL were extended by FGF-2. Moreover, FGF-2 increased the expression of bone morphogenetic protein 2 (BMP-2) and osteoblast differentiation markers (osterix, alkaline phosphatase, and osteocalcin) in the regenerated tissue. We revealed the facilitatory mechanisms of FGF-2 in periodontal regeneration in vivo. First, the proliferation of fibroblastic cells derived from bone marrow and PDL was accelerated and enhanced by FGF-2. Second, angiogenesis was enhanced by FGF-2 treatment. Finally, osteoblastic differentiation and bone formation, at least in part due to BMP-2 production, were rapidly induced by FGF-2. Therefore, these multifaceted effects of FGF-2 promote new tissue formation at the early regeneration phase, leading to enhanced formation of new bone, cementum, and PDL.


Asunto(s)
Factor 2 de Crecimiento de Fibroblastos/farmacología , Ligamento Periodontal/fisiología , Regeneración/efectos de los fármacos , Animales , Proliferación Celular/efectos de los fármacos , Perros , Femenino , Regulación de la Expresión Génica/efectos de los fármacos , Humanos , Neovascularización Fisiológica/efectos de los fármacos , Osteogénesis/efectos de los fármacos , Osteogénesis/genética , Ligamento Periodontal/irrigación sanguínea , Ligamento Periodontal/efectos de los fármacos , Ligamento Periodontal/patología , Raíz del Diente/irrigación sanguínea , Raíz del Diente/efectos de los fármacos , Raíz del Diente/patología
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