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3.
Heliyon ; 9(3): e14340, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36967976

RESUMEN

Objective: This study aims to compare the salivary and gingival crevicular fluid (GCF) concentrations of five cytokines: IL-1ß, IL-6, IL-17A, IL-33, and Tumor Necrosis Factor-alpha (TNF-α) in patients with OSA and their association with periodontitis. Methods: Samples of saliva and GCF were obtained from 84 patients classified into four groups according to periodontal and OSA diagnosis: G1(H) healthy patients, G2(P) periodontitis and non-OSA patients, G3(OSA) OSA and non-periodontitis patients, and G4(P-OSA) periodontitis and OSA patients. The cytokines in the samples were quantified using multiplexed bead immunoassays. Data were analyzed with the Kruskal-Wallis test, Dunn's multiple comparisons test, and the Spearman correlation test. Results: Stage III periodontitis was the highest in patients with severe OSA (69%; p=0.0142). Similar levels of IL-1ß and IL-6 in saliva were noted in G2(P) and G4(P-OSA). The IL-6, IL-17A and IL-33 levels were higher in the GCF of G4(P-OSA). There was a significant positive correlation between IL-33 in saliva and stage IV periodontitis in G4(P-OSA) (r s  = 0.531). The cytokine profile of the patients in G4(P-OSA) with Candida spp. had an increase of the cytokine's levels compared to patients who did not have the yeast. Conclusions: OSA may increase the risk of developing periodontitis due to increase of IL-1ß and IL-6 in saliva and IL-6, IL-17A and IL-33 in GCF that share the activation of the osteoclastogenesis. Those cytokines may be considered as biomarkers of OSA and periodontitis.

4.
Artículo en Inglés | MEDLINE | ID: mdl-36767109

RESUMEN

Periodontitis has been commonly linked to periodontopathogens categorized in Socransky's microbial complexes; however, there is a lack of knowledge regarding "other microorganisms" or "cryptic microorganisms", which are rarely thought of as significant oral pathogens and have been neither previously categorized nor connected to illnesses in the oral cavity. This study hypothesized that these cryptic microorganisms could contribute to the modulation of oral microbiota present in health or disease (periodontitis and/or obstructive sleep apnea (OSA) patients). For this purpose, the presence and correlation among these cultivable cryptic oral microorganisms were identified, and their possible role in both conditions was determined. Data from oral samples of individuals with or without periodontitis and with or without OSA were obtained from a previous study. Demographic data, clinical oral characteristics, and genera and species of cultivable cryptic oral microorganisms identified by MALDI-TOF were recorded. The data from 75 participants were analyzed to determine the relative frequencies of cultivable cryptic microorganisms' genera and species, and microbial clusters and correlations tests were performed. According to periodontal condition, dental-biofilm-induced gingivitis in reduced periodontium and stage III periodontitis were found to have the highest diversity of cryptic microorganism species. Based on the experimental condition, these findings showed that there are genera related to disease conditions and others related to healthy conditions, with species that could be related to different chronic diseases being highlighted as periodontitis and OSA comorbidities. The cryptic microorganisms within the oral microbiota of patients with periodontitis and OSA are present as potential pathogens, promoting the development of dysbiotic microbiota and the occurrence of chronic diseases, which have been previously proposed to be common risk factors for periodontitis and OSA. Understanding the function of possible pathogens in the oral microbiota will require more research.


Asunto(s)
Gingivitis , Microbiota , Periodontitis , Apnea Obstructiva del Sueño , Humanos , Periodontitis/epidemiología , Periodoncio , Apnea Obstructiva del Sueño/epidemiología
5.
Front Cell Infect Microbiol ; 12: 934298, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36189359

RESUMEN

Objective: The aim of this study was to analyze the cultivable oral microbiota of patients with obstructive sleep apnea (OSA) and its association with the periodontal condition. Methods: The epidemiology profile of patients and their clinical oral characteristics were determined. The microbiota was collected from saliva, subgingival plaque, and gingival sulcus of 93 patients classified into four groups according to the periodontal and clinical diagnosis: Group 1 (n = 25), healthy patients; Group 2 (n = 17), patients with periodontitis and without OSA; Group 3 (n = 19), patients with OSA and without periodontitis; and Group 4 (n = 32), patients with periodontitis and OSA. Microbiological samples were cultured, classified, characterized macroscopically and microscopically, and identified by MALDI-TOF-MS. The distribution of complexes and categories of microorganisms and correlations were established for inter- and intra-group of patients and statistically evaluated using the Spearman r test (p-value <0.5) and a multidimensional grouping analysis. Result: There was no evidence between the severity of OSA and periodontitis (p = 0.2813). However, there is a relationship between the stage of periodontitis and OSA (p = 0.0157), with stage III periodontitis being the one with the highest presence in patients with severe OSA (prevalence of 75%; p = 0.0157), with more cases in men. The greatest distribution of the complexes and categories was found in oral samples of patients with periodontitis and OSA (Group 4 P-OSA); even Candida spp. were more prevalent in these patients. Periodontitis and OSA are associated with comorbidities and oral conditions, and the microorganisms of the orange and red complexes participate in this association. The formation of the dysbiotic biofilm was mainly related to the presence of these complexes in association with Candida spp. Conclusion: Periodontopathogenic bacteria of the orange complex, such as Prevotella melaninogenica, and the yeast Candida albicans, altered the cultivable oral microbiota of patients with periodontitis and OSA in terms of diversity, possibly increasing the severity of periodontal disease. The link between yeasts and periodontopathogenic bacteria could help explain why people with severe OSA have such a high risk of stage III periodontitis. Antimicrobial approaches for treating periodontitis in individuals with OSA could be investigated in vitro using polymicrobial biofilms, according to our findings.


Asunto(s)
Periodontitis , Apnea Obstructiva del Sueño , Candida , Candida albicans , Causalidad , Encía/microbiología , Humanos , Masculino , Periodontitis/complicaciones , Periodontitis/epidemiología , Apnea Obstructiva del Sueño/complicaciones , Apnea Obstructiva del Sueño/epidemiología
6.
Cell Tissue Res ; 376(2): 221-231, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-30635775

RESUMEN

Testosterone (T) has been suggested as a promising agent in the bone osteointegration when incorporated in a bioceramic/polymer combination for the local application. The objective of this study was to evaluate the activity of a testosterone composite of poly (lactic-co-glycolic acid) (PLGA), polycaprolactone (PCL), and biphasic calcium phosphate (BCP) as a strategy for enhancing its osteogenic effect and to evaluate tissue response to the composite implantation. PLGA/PCL/BCP/T and PLGA/PCL/BCP composites were prepared and characterized using thermal analysis. Composite morphology and surface characteristics were assessed by SEM and EDS. The evaluations of in vitro effects of testosterone composite on osteoblasts viability, alkaline phosphatase activity, collagen production, osteocalcin concentration, quantification of mineralization, and nitric oxide concentration, after 7, 14, and 21 days. Testosterone was successfully incorporated and composites showed a homogeneously distributed porous structure. The PLGA/PCL/BCP/T composite had a stimulatory effect on osteoblastic activity on the parameters evaluated, except to nitric oxide production. After 60 days, the PLGA/PCL/BCP/T composite showed no chronic inflammatory infiltrate, whereas the PLGA/PCL/BCP composite showed mild chronic inflammatory infiltrate. Angiogenesis, cellular adsorption, and fibrous deposit were observed on the surfaces of implanted composites. The composites in combination with testosterone can be exploited to investigate the use of this scaffold for bone integration.


Asunto(s)
Materiales Biocompatibles , Osteogénesis/efectos de los fármacos , Testosterona/farmacología , Andamios del Tejido/química , Fosfatasa Alcalina/metabolismo , Animales , Materiales Biocompatibles/química , Materiales Biocompatibles/farmacología , Biomineralización/efectos de los fármacos , Supervivencia Celular , Células Cultivadas , Colágeno/metabolismo , Hidroxiapatitas/química , Masculino , Neovascularización Fisiológica/efectos de los fármacos , Óxido Nítrico/metabolismo , Osteoblastos/citología , Osteocalcina/metabolismo , Poliésteres/química , Copolímero de Ácido Poliláctico-Ácido Poliglicólico/química , Ratas , Ratas Wistar
7.
Front Microbiol ; 9: 667, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29681894

RESUMEN

The antimicrobial peptide LyeTxI isolated from the venom of the spider Lycosa erythrognatha is a potential model to develop new antibiotics against bacteria and fungi. In this work, we studied a peptide derived from LyeTxI, named LyeTxI-b, and characterized its structural profile and its in vitro and in vivo antimicrobial activities. Compared to LyeTxI, LyeTxI-b has an acetylated N-terminal and a deletion of a His residue, as structural modifications. The secondary structure of LyeTxI-b is a well-defined helical segment, from the second amino acid to the amidated C-terminal, with no clear partition between hydrophobic and hydrophilic faces. Moreover, LyeTxI-b shows a potent antimicrobial activity against Gram-positive and Gram-negative planktonic bacteria, being 10-fold more active than the native peptide against Escherichia coli. LyeTxI-b was also active in an in vivo model of septic arthritis, reducing the number of bacteria load, the migration of immune cells, the level of IL-1ß cytokine and CXCL1 chemokine, as well as preventing cartilage damage. Our results show that LyeTxI-b is a potential therapeutic model for the development of new antibiotics against Gram-positive and Gram-negative bacteria.

8.
Mater Sci Eng C Mater Biol Appl ; 83: 25-34, 2018 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-29208285

RESUMEN

Cancer is one of the leading causes of morbidity and mortality Worldwide, 19.3 million new cancer cases are expected to be identified in 2025. Among the therapeutic arsenal to cancer control one could find the Doxycycline and the nano hydroxyapatite. The Doxycycline (Dox) not only shown antibiotic effect but also exhibits a wide range of pleiotropic therapeutic properties as the control of the invasive and metastatic cancer cells characteristics. The purpose of the present study was to evaluate both cytotoxicity in vitro and antibacterial activity of electrospun Dox-loaded hybrid nanofibrous scaffolds composed by hydroxyapatite nanoparticles (nHA), poly-ε-caprolactone (PCL) and gelatin (Gel) polymers. Both nHA and Dox were dispersed into different PCL/Gel ratios (70:30, 60:40, 50:50wt%) solutions to form electrospun nanofibers. The nHA and Dox/nHA/PCL-Gel hybrid nanofibers were characterized by TEM microscopy. In vitro Dox release behavior from all of these Dox-loaded nHA/PCL-Gel nanofibers showed the same burst release profile due to the high solubility of Gel in the release medium. Antibacterial properties of nanofiber composites were evaluated using Gram-positive Staphylococcus aureus (S. aureus) and Gram-negative Porphyromonas gingivalis (P. gingivalis) bacteria. The co-delivery of nHA particles and Dox simultaneously exhibited inhibition of bacterial growth more efficiently than the delivery of either Dox or nHA at the same concentrations, indicating a synergistic effect. The results showed that cancer cell tested had different sensibility to co-delivery system. On the whole, A-431 cells were found exhibited the most pronounced synergistic effect compared to CACO-2 and 4T1 cancer cells. Based on the anticancer as well as the antimicrobial results in this study, the developed Dox/nHA/PCL-Gel composite nanofibers are suitable as a drug delivery system with potential applications in the biomedical fields.


Asunto(s)
Antibacterianos/química , Caproatos/química , Doxiciclina/química , Durapatita/química , Gelatina/química , Lactonas/química , Nanofibras/química , Nanopartículas/química , Antineoplásicos/química , Células CACO-2 , Sistemas de Liberación de Medicamentos , Sinergismo Farmacológico , Humanos , Nanofibras/ultraestructura , Nanopartículas/ultraestructura
9.
J Photochem Photobiol B ; 177: 85-94, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-29107206

RESUMEN

Bacterial soft rot is responsible for the loss of about 25% of worldwide production in vegetables and fruits. Efforts have been made to develop an effective nanosponge with the capacity to load and release antibacterial drugs to protect plants. Based on the potential of the ZnO nanoparticles (ZnO-NPs) to achieve this goal, this study synthesized NP via the sol-gel and hydrothermal methods by controlling native defects, such as oxygen vacancies, using thermal treatments and reduced atmospheres. To characterize the ZnO NPs, X-ray diffraction (XRD), Raman spectroscopy, transmission electron microscopy (TEM), optical spectroscopy, electron paramagnetic resonance (EPR), Zeta Potential measurements and surface area with the Brunauer-Emmett-Teller (BET) method were used. The photophysical and photochemical properties via spin trapping method aligned with EPR using UVA light showed a greater formation of electron-hole pairs and hydroxyl radicals for the reduced ZnO NPs when compared with the oxidized ones. Additionally, we found that reduced ZnO-NPs have high effectively against Escherichia coli, Erwinia carotovora and Pantoea sp. bacteria using the photocatalytic effect in the UV range. Moreover, ZnO-NPs loaded with DOX release profile enables the release of DOX within 46days, where 25% was released during the first 10h followed by a second delivery phase with an interesting short-term efficacy (<1day) against E. carotovora and Pantoea sp. Bacteria. For the first time, it was demonstrated that ZnO-NPs and ZnO-NPs loaded with DOX have efficient UV photocatalytic activities against bacterial soft rot infections.


Asunto(s)
Antibacterianos/química , Doxiciclina/química , Portadores de Fármacos/química , Nanopartículas del Metal/química , Óxido de Zinc/química , Antibacterianos/farmacología , Catálisis , Liberación de Fármacos , Espectroscopía de Resonancia por Spin del Electrón , Escherichia coli/efectos de los fármacos , Escherichia coli/efectos de la radiación , Pruebas de Sensibilidad Microbiana , Oxidación-Reducción , Pantoea/efectos de los fármacos , Tamaño de la Partícula , Pectobacterium carotovorum/efectos de los fármacos , Pectobacterium carotovorum/efectos de la radiación , Rayos Ultravioleta
10.
Carbohydr Polym ; 163: 1-9, 2017 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-28267484

RESUMEN

In the present work, we study the role of different components in the formation of more stable iron oxide magnetic nanoparticles (MNPs): ß-cyclodextrin (BCD), 2-hydroxypropyl-ß-cyclodextrin (HP) and citrate anion. MNPs formulations were characterized by FTIR, particles size measurements, zeta potential based on dynamic light scattering principle technique, X-ray powder pattern diffraction, XPS spectroscopy, transmission electron microscopy and thermogravimetric analysis. The results showed that cyclodextrins and citrate plays a key role in order to obtain a lower size of coated MNPs and proved to be an efficient strategy to obtain a more stable colloidal dispersion, avoiding the nanoparticles oxidation, enhancing the irinotecan incorporation and release. Furthermore, citrate-coated BCD-MNPs showed the same cytotoxicity of the free IRI.

11.
Photodiagnosis Photodyn Ther ; 18: 252-256, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28344047

RESUMEN

BACKGROUND: Photodynamic therapy (PDT) is an antitumour treatment that employs the combination of a photosensitive compound, oxygen and visible light. To improve the antitumour activity of PDT, the present study used the strategy of combining PDT with erlotinib (ERL), a drug frequently used in the treatment of epidermoid carcinoma. METHODS: An MTT cell viability assay was used to evaluate the cytotoxicity of PDT combined with ERL on A431 epidermoid carcinoma cells in vitro. This study evaluated the cytotoxicity of the following treatments: red laser irradiation (660nm) at different power densities (1.25-180J/cm2), the photosensitizer methylene blue (MB) at concentrations of 0.39-100µM, PDT (12.5µM MB and laser power densities from 1.25 to 180J/cm2), and PDT (12.5µM MB and a laser density of 120J/cm2) plus ERL (1µM). RESULTS: The laser power densities that were tested showed no cytotoxicity in A431 cells. MB showed a dose-dependent cytotoxicity. In PDT, an increase in the dose of light resulted in an increase in the cytotoxicity of MB. In addition, there was a sub-additive effect between PDT and ERL compared to the effect of each therapy alone. CONCLUSIONS: The sub-additive effect between PDT and ERL suggests that their combination may be an important strategy in the treatment of epidermoid carcinoma.


Asunto(s)
Carcinoma de Células Escamosas/tratamiento farmacológico , Carcinoma de Células Escamosas/patología , Quimioradioterapia/métodos , Clorhidrato de Erlotinib/administración & dosificación , Fotoquimioterapia/métodos , Antineoplásicos/administración & dosificación , Apoptosis/efectos de los fármacos , Apoptosis/efectos de la radiación , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Supervivencia Celular/efectos de la radiación , Terapia Combinada/métodos , Relación Dosis-Respuesta a Droga , Relación Dosis-Respuesta en la Radiación , Humanos , Fármacos Fotosensibilizantes/administración & dosificación , Dosis de Radiación , Resultado del Tratamiento
12.
Carbohydr Polym ; 156: 417-426, 2017 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-27842841

RESUMEN

This study aimed to compare two nanofiber drug delivery systems that were prepared with an electrospun process and have the potential to serve as adjuvants for the treatment of periodontal disease. The first system was composed of polycaprolactone loaded with tetracycline (TCN) and the second was composed of polycaprolactone loaded with tetracycline/ß-cyclodextrin (TCN:BCD). An antimicrobial diffusion test was performed for each of these sets of nanofibers with the microorganisms, Aggregatibacter actinomycetemcomitans and Porphyromonas gingivalis, both of which contribute to periodontal disease. In vitro release profiles were also obtained, and the nanofibers were characterized by thermal analysis, x-ray powder diffraction, infrared absorption spectroscopy, and scanning electron microscopy. Profiles of the TCN and TCN:BCD nanofibers showed that drug release occurred for up to 14days. However, the TCN:BCD nanofibers appeared to better protect and enhance the biological absorption of TCN due to the formation of a TCN:BCD inclusion complex.


Asunto(s)
Aggregatibacter/efectos de los fármacos , Nanofibras/química , Porphyromonas/efectos de los fármacos , Tetraciclina/química , Tetraciclina/farmacología , beta-Ciclodextrinas/química , beta-Ciclodextrinas/farmacología , Antiinfecciosos/química , Antiinfecciosos/farmacología , Pruebas de Sensibilidad Microbiana
13.
Biointerphases ; 11(4): 04B307, 2016 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-27907988

RESUMEN

The aim of this study was to determine the physical properties and antimicrobial and antiproliferative effects of the KR12 peptide complexed with 2-hydroxypropyl-ß-cyclodextrin (Hp-ßCd) in vitro. The KR12:Hp-ßCd composition was evaluated for particle size and its zeta (ζ)-potential in the presence and absence of cells. Antimicrobial activity against Streptococcus mutans, Actinobacillus actinomycetemcomitans, and Porphyromonas gingivalis for the peptide alone or associated was evaluated by minimal inhibitory concentration. The cytotoxicity of the peptide and composition toward fibroblasts, Caco-2 cells, and A431 cells was determined using the 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide; thiazolyl blue assay and hemolysis assay. Membrane integrity was analyzed by the lactate dehydrogenase assay. KR12:Hp-ßCd decreased the peptide concentration required for the antimicrobial effect. Moreover, this composition was able to modify cell surface parameters, such as ζ-potential, and alter the degree of hemolysis induced by KR12. However, the KR12:Hp-ßCd and KR12 alone alter the zeta potential of cells to a similar extent, suggesting a similar level of membrane interaction. The peptide alone inhibited the proliferation of Caco-2 and A431 cells more efficiently than KR12:Hp-ßCd (p < 0.001), but did not show significant cytotoxic effects via the dehydrogenase lactate assay. Both substances were effective in inhibiting the growth of odontopathogenic bacteria, as well as inhibiting Caco-2 epithelial cells. These observations highlight the potential antimicrobial and antiproliferative effects of KR12 peptide alone or associated with Hp-ßCd.


Asunto(s)
Antibacterianos/farmacología , Antineoplásicos/farmacología , Bacterias/efectos de los fármacos , Ciclodextrinas/farmacología , Células Epiteliales/efectos de los fármacos , Fibroblastos/efectos de los fármacos , Péptidos/farmacología , Línea Celular , Supervivencia Celular/efectos de los fármacos , Ciclodextrinas/síntesis química , Eritrocitos/efectos de los fármacos , Hemólisis , Humanos , L-Lactato Deshidrogenasa/análisis , Pruebas de Sensibilidad Microbiana , Péptidos/síntesis química
14.
Neuroscience ; 337: 224-241, 2016 Nov 19.
Artículo en Inglés | MEDLINE | ID: mdl-27615031

RESUMEN

The theta rhythm is necessary for hippocampal-dependent spatial learning. It has been proposed that each hippocampal stratum can generate a current theta dipole. Therefore, considering that each hippocampal circuit (CA1, CA3, and Dentate Gyrus (DG)) contributes differently to distinct aspects of a spatial memory, the theta oscillations on each stratum and their couplings may exhibit oscillatory dynamics associated with different stages of learning. To test this hypothesis, the theta oscillations from five hippocampal strata were recorded in the rat during different stages of learning in a Morris maze. The peak power, the relative power (RP) and the coherence between hippocampal strata were analyzed. The early acquisition stage of the Morris task was characterized by the predominance of slow frequency theta activity and high coupling between specific hippocampal strata at slow frequencies. However, on the last training day, the theta oscillations were faster in all hippocampal strata, with tighter coupling at fast frequencies between the CA3 pyramidal stratum and other strata. Our results suggest that modifications to the theta frequency and its coupling can be a means by which the hippocampus differentially operates during acquisition and retrieval states.


Asunto(s)
Hipocampo/fisiología , Memoria/fisiología , Aprendizaje Espacial/fisiología , Ritmo Teta/fisiología , Animales , Conducta Animal/fisiología , Giro Dentado/fisiología , Masculino , Ratas Sprague-Dawley
15.
Front Pharmacol ; 6: 250, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26578960

RESUMEN

Hippocampal theta activity is related to spatial information processing, and high-frequency theta activity, in particular, has been linked to efficient spatial memory performance. Theta activity is regulated by the synchronizing ascending system (SAS), which includes mesencephalic and diencephalic relays. The supramamillary nucleus (SUMn) is located between the reticularis pontis oralis and the medial septum (MS), in close relation with the posterior hypothalamic nucleus (PHn), all of which are part of this ascending system. It has been proposed that the SUMn plays a role in the modulation of hippocampal theta-frequency; this could occur through direct connections between the SUMn and the hippocampus or through the influence of the SUMn on the MS. Serotonergic raphe neurons prominently innervate the hippocampus and several components of the SAS, including the SUMn. Serotonin desynchronizes hippocampal theta activity, and it has been proposed that serotonin may regulate learning through the modulation of hippocampal synchrony. In agreement with this hypothesis, serotonin depletion in the SUMn/PHn results in deficient spatial learning and alterations in CA1 theta activity-related learning in a Morris water maze. Because it has been reported that SUMn inactivation with lidocaine impairs the consolidation of reference memory, we asked whether changes in hippocampal theta activity related to learning would occur through serotonin depletion in the SUMn, together with deficiencies in memory. We infused 5,7-DHT bilaterally into the SUMn in rats and evaluated place learning in the standard Morris water maze task. Hippocampal (CA1 and dentate gyrus), septal and SUMn EEG were recorded during training of the test. The EEG power in each region and the coherence between the different regions were evaluated. Serotonin depletion in the SUMn induced deficient spatial learning and altered the expression of hippocampal high-frequency theta activity. These results provide evidence in support of a role for serotonin as a modulator of hippocampal learning, acting through changes in the synchronicity evoked in several relays of the SAS.

16.
Colloids Surf B Biointerfaces ; 136: 248-55, 2015 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-26402423

RESUMEN

The objective of this study was to evaluate the in vivo anti-inflammatory angiogenesis activity and in vitro cytotoxicity on normal and cancer cell models of a drug delivery system consisting of poly(lactic-co-glycolic acid) nanofibers loaded with daunorubicin (PLGA-DNR) that were fabricated using an electrospinning process. The PLGA-DNR nanofibers were also characterized by thermogravimetric analysis (TGA), differential thermal analysis (DTA) and differential scanning calorimetry (DSC), X-ray diffraction (XRD), scanning electron microscopy (SEM) and confocal fluorescence microscopy. In vitro release of DNR from the nanofibers and its corresponding mechanism were also evaluated. Sixty-five percent of the DNR was released in an initial burst over 8h, and by 1224 h, eighty-five percent of the DNR had been released. The Higuchi model yielded the best fit to the DNR release profile over the first 8h, and the corresponding data from 24 to 1224 h could be modeled using zero-order kinetics. The PLGA-DNR nanofibers exhibited a higher cytotoxicity to A431 cells than free DNR but a cytotoxicity similar to free DNR against fibroblast cells. A higher antiangiogenic effect of PLGA nanofibers was observed in the in vivo data when compared to free DNR, and no inflammatory potential was observed for the nanofibers.


Asunto(s)
Antibióticos Antineoplásicos/farmacología , Daunorrubicina/farmacología , Ácido Láctico/química , Nanofibras , Ácido Poliglicólico/química , Animales , Línea Celular , Línea Celular Tumoral , Humanos , Masculino , Ratones , Microscopía Electrónica de Rastreo , Microscopía Fluorescente , Copolímero de Ácido Poliláctico-Ácido Poliglicólico , Difracción de Rayos X
17.
Indian J Dent Res ; 26(3): 284-8, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26275197

RESUMEN

AIM: The aim of this study was to evaluate the correlation between the cytotoxicity and degree of conversion (DC) of self-etch resin cements with or without photopolymerization. MATERIALS AND METHODS: Three self-etching resin cements with or without photopolymerization were evaluated. Six test groups and one control group represented by a standardized L929-fibroblast cell culture were formed. The DC was measured by Fourier transform infrared spectrometry and was correlated with cell culture survival. STATISTICAL ANALYSIS: The analysis of variance and Bonferroni-Holm tests were applied (P < 0.05). RESULTS: The results show that, the cytotoxicity of self-etching resin cements is directly related to the DC. With the exception of Unicem, the other cements show some level of cytotoxicity, even with photopolymerization. CONCLUSION: These results indicate that photopolymerization of dual cure self-etching resin cements decrease toxic effects on cell culture. Adequate photopolymerization should be considered during cementation when using dual polymerization self-etching resin cements.


Asunto(s)
Fibroblastos/metabolismo , Cementos de Resina/química , Animales , Supervivencia Celular , Humanos , Ratones , Polimerizacion
18.
Mater Sci Eng C Mater Biol Appl ; 54: 252-61, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26046289

RESUMEN

Herein, we used an electrospinning process to develop highly efficacious and hydrophobic coaxial nanofibers based on poly-cyclodextrin (polyCD) associated with poly(methacrylic acid) (PMAA) that combines polymeric and supramolecular features for modulating the release of the hydrophilic drug, propranolol hydrochloride (PROP). For this purpose, polyCD was synthesized and characterized, and its biocompatibility was assessed using fibroblast cytotoxicity tests. Moreover, the interactions between the guest PROP molecule and both polyCD and ßCD were found to be spontaneous. Subsequently, PROP was encapsulated in uniaxial and coaxial polyCD/PMAA nanofibers. A lower PROP burst effect (reduction of approximately 50%) and higher modulation were observed from the coaxial than from the uniaxial fibers. Thus, the coaxial nanofibers could potentially be a useful strategy for developing a controlled release system for hydrophilic molecules.


Asunto(s)
Celulosa/química , Ciclodextrinas/química , Sistemas de Liberación de Medicamentos/métodos , Nanofibras/química , Ácidos Polimetacrílicos/química , Materiales Biocompatibles/química , Células Cultivadas , Células Inmovilizadas , Fibroblastos/citología , Fibroblastos/efectos de los fármacos , Encía/citología , Encía/efectos de los fármacos , Humanos , Interacciones Hidrofóbicas e Hidrofílicas , Espectroscopía de Resonancia Magnética , Microscopía Electrónica de Transmisión
19.
Molecules ; 19(9): 13948-64, 2014 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-25197932

RESUMEN

Current procedures for the detection and identification of bacterial infections are laborious, time-consuming, and require a high workload and well-equipped laboratories. Therefore the work presented herein developed a simple, fast, and low cost method for bacterial detection based on hydroxyapatite nanoparticles with a nutritive mixture and the fluorogenic substrate. Calcium phosphate ceramic nanoparticles were characterized and integrated with a nutritive mixture for the early detection of bacteria by visual as well as fluorescence spectroscopy techniques. The composite was obtained by combining calcium phosphate nanoparticles (Ca:P ratio, 1.33:1) with a nutritive mixture of protein hydrolysates and carbon sources, which promote fast bacterial multiplication, and the fluorogenic substrate 4-methylumbellipheryl-ß-D-glucuronide (MUG). The composite had an average particle size of 173.2 nm and did not show antibacterial activity against Gram-negative or Gram-positive bacteria. After an Escherichia coli suspension was in contact with the composite for 60-90 min, fluorescence detected under UV light or by fluorescence spectrophotometer indicated the presence of bacteria. Intense fluorescence was observed after incubation for a maximum of 90 min. Thus, this calcium phosphate nanocomposite system may be useful as a model for the development of other nanoparticle composites for detection of early bacterial adhesion.


Asunto(s)
Cerámica/química , Hidroxiapatitas/química , Nanocompuestos/química , Antibacterianos/química , Antibacterianos/farmacología , Infecciones Bacterianas/diagnóstico , Enterococcus faecalis/efectos de los fármacos , Escherichia coli/efectos de los fármacos , Humanos , Hidroxiapatitas/farmacología , Límite de Detección , Nanocompuestos/ultraestructura , Tamaño de la Partícula , Pseudomonas aeruginosa/efectos de los fármacos , Espectrometría de Fluorescencia , Staphylococcus aureus/efectos de los fármacos , Propiedades de Superficie
20.
Biointerphases ; 9(2): 029018, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24985222

RESUMEN

Nano- or microhydroxyapatites with microbiological properties are being used to detect pathogens in clinical samples and industrial environments. In this study, the calcium phosphates coral-hydroxyapatite and biphasic calcium phosphate were characterized physicochemically using x-ray diffraction, thermogravimetric, and differential thermal analysis. The morphology, texture, and chemical composition of the ceramics were also investigated using scanning electron microscopy with energy dispersive spectroscopy. The biocompatibility of the ceramics was evaluated using Escherichia coli and Enterococcus faecalis. Microorganisms were detected by incorporating the enzyme markers 4-metilumbelliferil-ß-d-glucoside and 4-metilumbelliferil-ß-d-glucuronide in the ceramic powders and evaluating fluorescence. The characterization of the ceramics revealed typical characteristics, such as crystallinity, thermal stability, and chemical composition, consistent with other calcium phosphates. The calcium phosphates coral-hydroxyapatite and biphasic calcium phosphate ceramics differed from one another in morphology, structural topography, particle size distribution, and the capacity to absorb water. These properties can influence the rates of microbiological responses and bacterial detection. Although both materials are suitable for use as structural supports in microbial diagnostic systems, BCP was more efficient and detected E. coli and E. faecalis more rapidly than CHA.


Asunto(s)
Antozoos/metabolismo , Materiales Biocompatibles/metabolismo , Fosfatos de Calcio/química , Durapatita/química , Enterococcus faecalis/aislamiento & purificación , Escherichia coli/aislamiento & purificación , Animales , Materiales Biocompatibles/química , Cerámica/química , Enterococcus faecalis/metabolismo , Escherichia coli/metabolismo , Colorantes Fluorescentes/química , Colorantes Fluorescentes/metabolismo , Glucurónidos/química , Glucurónidos/metabolismo , Tamaño de la Partícula , Espectrometría de Fluorescencia , Rayos Ultravioleta
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