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1.
Mar Drugs ; 20(1)2022 Jan 06.
Artículo en Inglés | MEDLINE | ID: mdl-35049910

RESUMEN

This study aimed to investigate the potential use of brown algae Sargassum polycystum as irreversible hydrocolloid (alginate) impression material. Potassium alginate extracted from Sargassum polycystum was prepared in three different compositions (14%, 15%, and 16%) and mixed with other standard components to form an alginate impression material. Prior to that, the purity of potassium alginate was quantified with Fourier Transform Infrared Spectroscopy (FTIR) analysis. As a control material, the alginate impression material from a commercially available product was used. All alginate impression materials were then applied to a die stone model. Dimensional accuracy was measured by calculating the mesiodistal width of incisors in the generated dental cast using a digital caliper 0.01 accuracy (five replications). In addition, to evaluate the dimensional stability, the impression results were poured at four different periods (immediately, 5 min, 10 min, and 15 min). An independent t-test was performed to compare the measurement results with p < 0.05 considered significant. Analytical results confirm that the impression material containing 15% potassium alginate gives the best dimensional accuracy similar to control (p > 0.05). Meanwhile, the optimal dimensional stability was produced in the impression material containing 16% potassium alginate. Our study suggested that brown algae Sargassum polycystum has a promising potential to be used as an alginate impression material in clinical application.


Asunto(s)
Coloides/química , Materiales de Impresión Dental/química , Sargassum , Animales , Organismos Acuáticos , Ensayo de Materiales
2.
Int J Mol Sci ; 23(3)2022 Jan 27.
Artículo en Inglés | MEDLINE | ID: mdl-35163411

RESUMEN

The ability of Pluronic F127 (PF127) conjugated with tetrapeptide Gly-Arg-Gly-Asp (GRGD) as a sequence of Arg-Gly-Asp (RGD) peptide to form the investigated potential hydrogel (hereafter referred to as 3DG bioformer (3BE)) to produce spheroid, biocompatibility, and cell invasion ability, was assessed in this study. The fibroblast cell line (NIH 3T3), osteoblast cell line (MG-63), and human breast cancer cell line (MCF-7) were cultured in the 3BE hydrogel and commercial product (Matrigel) for comparison. The morphology of spheroid formation was evaluated via optical microscopy. The cell viability was observed through cell counting Kit-8 assay, and cell invasion was investigated via Boyden chamber assay. Analytical results indicated that 3BE exhibited lower spheroid formation than Matrigel. However, the 3BE appeared biocompatible to NIH 3T3, MG-63, and MCF-7 cells. Moreover, cell invasion ability and cell survival rate after invasion through the 3BE was displayed to be comparable to Matrigel. Thus, these findings demonstrate that the 3BE hydrogel has a great potential as an alternative to a three-dimensional cell culture for drug screening applications.


Asunto(s)
Materiales Biocompatibles/química , Materiales Biomiméticos/química , Hidrogeles/química , Oligopéptidos/química , Poloxámero/química , Animales , Evaluación Preclínica de Medicamentos , Humanos , Células MCF-7 , Ratones , Células 3T3 NIH
3.
Am J Dent ; 33(4): 178-182, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32794390

RESUMEN

PURPOSE: evaluate the influence of an erbium, chromium: yttrium, scandium, gallium, garnet (Er,Cr:YSGG) laser using multiple tip types, on the removal of retained cement on a titanium implant surface. METHODS: Nine titanium dental implants were coated with a non-eugenol resin composite implant cement. An Er,Cr:YSGG device at a wavelength of 2,780 nm was fitted sequentially with three laser fiber tips: (1) 6 mm long, 600 µm diameter end-firing, quartz; (2) 9 mm long, Radial-Firing Perio Tip, 500 µm diameter, quartz; and (3) 18 mm long Side-Firing Tip, 800 µm x 300 µm, sapphire. Irradiation on the implant surfaces was performed in short pulse mode (140 µsec pulse duration) with output power of 1.5 W, 50% water, 40% air, and either: (1) 15 Hz, 100 mJ/pulse; (2) 30 Hz, 50 mJ/pulse; or (3) 40 Hz, 37.5 mJ/pulse. Three trials each were completed for each of three different fiber tip types for a total of 27 trials (three trials for each of the nine groups). RESULTS: All samples in Groups 1-6 demonstrated complete removal of cement from the implant surface. SEM inspection revealed a high degree of melting of the resin composite cement on the implant surface in all samples treated with 100 mJ/pulse (Groups 1, 2, 3). At 50 mJ/pulse (30 Hz), the results of the end-firing and side-firing tips improved remarkably, with clean implant surfaces and comparatively little melting. The side-firing fiber at 50 mJ/pulse and 30 Hz provided the best overall combination of cement removal and least amount of residual melted material on the implant surface. Based on the limitations of this study, the most appropriate method of removing residual cement from a TiUnite coated titanium implant surface is by using an Er,Cr:YSGG laser device fitted with a side-firing laser tip. Laser parameters of 50 mJ/pulse and 30 Hz (1.5W average power), with at least 50% water and 40% air in the aerosolized water spray are ideal. CLINICAL SIGNIFICANCE: As the presence of peri-implantitis continues to increase in numbers and severity, it is imperative to have a predictable treatment protocol to address the large number of ailing and failing implant cases. This study offers one solution to the problem of peri-implantitis, especially if caused by retained cement. Optimal laser settings are proposed for surface decontamination and treatment.


Asunto(s)
Implantes Dentales , Terapia por Láser , Láseres de Estado Sólido , Cementos de Resina , Titanio
4.
Int J Mol Sci ; 21(2)2020 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-31963217

RESUMEN

The main aim of this study is to develop a one-stage method to combine platelet-rich fibrin (PRF) and autologous cartilage autografts for porcine articular cartilage repair. The porcine chondrocytes were treated with different concentrations of PRF-conditioned media and were evaluated for their cell viability and extracellular glycosaminoglycan (GAG) synthesis during six day cultivation. The chemotactic effects of PRF on chondrocytes on undigested cartilage autografts were revealed in explant cultures. For the in vivo part, porcine chondral defects were created at the medial femoral condyles of which were (1) left untreated, (2) implanted with PRF combined with hand-diced cartilage grafts, or (3) implanted with PRF combined with device-diced cartilage grafts. After six months, gross grades, histological, and immunohistochemical analyses were compared. The results showed that PRF promotes the viability and GAG expression of the cultured chondrocytes. Additionally, the PRF-conditioned media induce significant cellular migration and outgrowth of chondrocytes from undigested cartilage grafts. In the in vivo study, gross grading and histological scores showed significantly better outcomes in the treatment groups as compared with controls. Moreover, both treatment groups showed significantly more type II collagen staining and minimal type I collagen staining as compared with controls, indicating more hyaline-like cartilage and less fibrous tissue. In conclusion, PRF enhances the viability, differentiation, and migration of chondrocytes, thus, showing an appealing capacity for cartilage repair. The data altogether provide evidences to confirm the feasibility of a one-stage, culture-free method of combining PRF and cartilage autografts for repairing articular cartilage defects. From translational standpoints, these advantages benefit clinical applications by simplifying and potentiating the efficacy of cartilage autograft transplants.


Asunto(s)
Cartílago Articular/citología , Movimiento Celular/fisiología , Supervivencia Celular/fisiología , Condrocitos/citología , Fibrina Rica en Plaquetas/química , Animales , Cartílago Articular/metabolismo , Diferenciación Celular/fisiología , Proliferación Celular/fisiología , Células Cultivadas , Glicosaminoglicanos/metabolismo , Articulación de la Rodilla/citología , Porcinos , Porcinos Enanos , Trasplante Autólogo
5.
Int J Mol Sci ; 21(9)2020 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-32370197

RESUMEN

Cancer pathogenesis results from genetic alteration-induced high or low transcriptional programs, which become highly dependent on regulators of gene expression. However, their role in progressive regulation of non-small-cell lung cancer (NSCLC) and how these dependencies may offer opportunities for novel therapeutic options remain to be understood. Previously, we identified forkhead box F1 (FOXF1) as a reprogramming mediator which leads to stemnesss when mesenchymal stem cells fuse with lung cancer cells, and we now examine its effect on lung cancer through establishing lowly and highly expressing FOXF1 NSCLC engineered cell lines. Higher expression of FOXF1 was enabled in cell lines through lentiviral transduction, and their viability, proliferation, and anchorage-dependent growth was assessed. Flow cytometry and Western blot were used to analyze cellular percentage in cell-cycle phases and levels of cellular cyclins, respectively. In mice, tumorigenic behavior of FOXF1 was investigated. We found that FOXF1 was downregulated in lung cancer tissues and cancer cell lines. Cell proliferation and ability of migration, anchorage-independent growth, and transformation were inhibited in H441-FOXF1H and H1299-FOXF1H, with upregulated tumor suppressor p21 and suppressed cellular cyclins, leading to cell-cycle arrest at the gap 1 (G1) phase. H441-FOXF1H and H1299-FOXF1H injected mice showed reduced tumor size. Conclusively, highly expressing FOXF1 inhibited NSCLC growth via activating tumor suppressor p21 and G1 cell-cycle arrest, thus offering a potentially novel therapeutic strategy for lung cancer.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas/genética , Factores de Transcripción Forkhead/genética , Puntos de Control de la Fase G1 del Ciclo Celular/genética , Regulación Neoplásica de la Expresión Génica , Neoplasias Pulmonares/genética , Proteínas Supresoras de Tumor/genética , Animales , Carcinoma de Pulmón de Células no Pequeñas/metabolismo , Carcinoma de Pulmón de Células no Pequeñas/terapia , Línea Celular Tumoral , Proliferación Celular/genética , Inhibidor p21 de las Quinasas Dependientes de la Ciclina/genética , Inhibidor p21 de las Quinasas Dependientes de la Ciclina/metabolismo , Factores de Transcripción Forkhead/metabolismo , Humanos , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/terapia , Ratones Endogámicos NOD , Ratones SCID , Carga Tumoral/genética , Proteínas Supresoras de Tumor/metabolismo , Ensayos Antitumor por Modelo de Xenoinjerto/métodos
6.
Sensors (Basel) ; 19(2)2019 Jan 18.
Artículo en Inglés | MEDLINE | ID: mdl-30669377

RESUMEN

Acupuncture is a practice of treatment based on influencing specific points on the body by inserting needles. According to traditional Chinese medicine, the aim of acupuncture treatment for pain management is to use specific acupoints to relieve excess, activate qi (or vital energy), and improve blood circulation. In this context, the Hegu point is one of the most widely-used acupoints for this purpose, and it has been linked to having an analgesic effect. However, there exists considerable debate as to its scientific validity. In this pilot study, we aim to identify the functional connectivity related to the three main types of acupuncture manipulations and also identify an analgesic effect based on the hemodynamic response as measured by functional near-infrared spectroscopy (fNIRS). The cortical response of eleven healthy subjects was obtained using fNIRS during an acupuncture procedure. A multiscale analysis based on wavelet transform coherence was employed to assess the functional connectivity of corresponding channel pairs within the left and right somatosensory region. The wavelet analysis was focused on the very-low frequency oscillations (VLFO, 0.01⁻0.08 Hz) and the low frequency oscillations (LFO, 0.08⁻0.15 Hz). A mixed model analysis of variance was used to appraise statistical differences in the wavelet domain for the different acupuncture stimuli. The hemodynamic response after the acupuncture manipulations exhibited strong activations and distinctive cortical networks in each stimulus. The results of the statistical analysis showed significant differences ( p < 0.05 ) between the tasks in both frequency bands. These results suggest the existence of different stimuli-specific cortical networks in both frequency bands and the anaesthetic effect of the Hegu point as measured by fNIRS.

7.
Surg Endosc ; 30(7): 3035-49, 2016 07.
Artículo en Inglés | MEDLINE | ID: mdl-26563510

RESUMEN

BACKGROUND: Minimally invasive surgery is performed using an endoscope and other instruments including the electrosurgical units. However, concerns including surgical smoke, tissue sticking and thermal injury are remaining in electrosurgery. AIMS: Accordingly, a newly developed electrosurgical electrode coating with hydrogenated Cu-incorporated diamond-like carbon (DLC-Cu) film is purposed to improve the instrument performance. METHODS: The morphologies of DLC-Cu surfaces were characterized using transmission electron microscopy, scanning electron microscopy and atomic force microscopy. In this study, lesions were made on the liver lobes of adult rats, using a monopolar electrosurgical unit equipped with untreated stainless steel electrodes or treated-electrodes. Animals were killed for evaluations at 0, 3, 7 and 28 days postoperatively. RESULTS: Treated-electrodes generate less sticking tissues and adhesive blood cells. Thermography revealed that the surgical temperature in liver tissue from the treated-electrode was significantly lower than the untreated-electrode. Total injury area of livers treated with treated-electrodes was significantly smaller than the untreated-electrodes treatment. Moreover, treated-electrodes caused a relatively smaller area of lateral thermal injury, a smaller area of fibrotic tissue and a faster process of remodeling than the untreated-electrodes. Western blot analysis showed that rats treated with treated-electrode expressed lower levels of NF-κB, caspase-3 and MMP-9 than untreated-electrode. Immunofluorescence staining for caspase-3 revealed that the untreated-electrode caused more serious injury. CONCLUSIONS: This study reveals that the plating of electrodes with hydrogenated Cu-incorporated diamond-like carbon film is an efficient method for improving the performance of electrosurgical units, and should benefit wound remodeling. However, more tests must be carried out to confirm these promising findings in human patients.


Asunto(s)
Materiales Biocompatibles Revestidos/química , Electrodos , Electrocirugia/instrumentación , Nanoestructuras , Animales , Western Blotting , Quemaduras/patología , Quemaduras/prevención & control , Carbono/química , Caspasa 3/metabolismo , Cobre/química , Modelos Animales de Enfermedad , Hígado/cirugía , Metaloproteinasa 9 de la Matriz/metabolismo , Microscopía Electrónica de Rastreo , Microscopía Electrónica de Transmisión , Procedimientos Quirúrgicos Mínimamente Invasivos/instrumentación , Procedimientos Quirúrgicos Mínimamente Invasivos/métodos , FN-kappa B/metabolismo , Ratas , Acero Inoxidable/química , Temperatura , Termografía
8.
Clin Oral Investig ; 20(7): 1515-24, 2016 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26507647

RESUMEN

PURPOSE: Electrochemical oxidation following sandblasting and acid-etching (SLA) treatment has received interest as a surface modification procedure for titanium (Ti) implants (denoted as an SLAffinity surface); however, little information is available on its impacts on the in vivo performance of SLAffinity-Ti implants. The present study evaluated the osseointegration and biomechanical bone-tissue response to SLAffinity-Ti implants with micro- and nanoporous oxide layers. MATERIALS AND METHODS: The interaction between blood and the tested implants was examined. In total, 144 implants with the following surfaces were used: a standard machined (M-Ti), an SLA-Ti, and an SLAffinity-Ti surface. For each animal, four implants (one M-Ti, one SLA-Ti, and two SLAffinity-Ti) were inserted into the mandibular canine-premolar area for histomorphometric observations and another four implants were inserted into the flat surface on the anteromedial aspect of the rear tibia for removal torque (RT) tests. After 2, 4, and 8 weeks of implantation, histomorphometric and RT tests were conducted. RESULTS: Interactions between blood and implants were better for implants with the SLAffinity-Ti surface. RT tests showed a significant improvement in fixation strength for SLAffinity-Ti implants (84.5 ± 8.7 N-cm) after 8 weeks compared to M-Ti (62.95 ± 11.5 N-cm) and SLAffinity-Ti (76.1 ± 6.6 N-cm) implants. A histological evaluation showed that osseous integration had occurred with all implants after 8 weeks. SLAffinity-Ti implants exhibited 28.5 ± 6.2 % bone-to-implant contact (BIC) at 2 weeks and 84.3 ± 8.1 % at 8 weeks. M-Ti implants exhibited BIC levels of 17.0 ± 5.4 and 76.5 ± 6.3 %, whereas SLA-Ti implants exhibited BIC levels of 28.5 ± 6.2 and 81.1 ± 8.4 % at corresponding time intervals. In terms of the peri-implant bone area (BA), values for SLAffinity-Ti implants ranged from 29.5 ± 4.1 to 88.3 ± 3.0 %. For M-Ti implants, values ranged from 20.3 ± 5.5 to 81.7 ± 4.2 %. For SLA-Ti implants, values ranged from 23.0 ± 3.5 to 84.0 ± 3.6 %. CONCLUSIONS: Electrochemical oxidation increased the oxide layers and improved the blood interaction with SLAffinity-Ti implants, resulting in significantly higher bone apposition with the SLAffinity-Ti implants after 2 and 8 weeks of healing. An increase in resistance for the RT of SLAffinity-Ti implants over the 8-week healing period was also observed. CLINICAL RELEVANCE: The use of SLAffinity-Ti implants has potential for improvement of early osseointegration.


Asunto(s)
Implantación Dental Endoósea/métodos , Implantes Dentales , Oseointegración/fisiología , Tibia/cirugía , Grabado Ácido Dental , Animales , Pulido Dental , Implantes Experimentales , Porosidad , Propiedades de Superficie , Porcinos , Porcinos Enanos , Titanio/química , Torque
9.
Acta Odontol Scand ; 74(5): 328-34, 2016 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-26758348

RESUMEN

Objective To provide an update on what is known about bruxism and some of the major clinical highlights derived from new insights into this old problem in dentistry. Materials and methods A selective, non-systematic but critical review of the available scientific literature was performed. Results There are two main different types of bruxism, which are related to different circadian periods (sleep and awake bruxism) that may differ in terms of pathophysiology, but they share some common signs and symptoms. Approximately one out of 10 adult individuals may suffer from bruxism, but not all bruxers may need treatment. Bruxism is complicated to diagnose in the clinic and self-report of bruxism may not necessarily reflect the true presence of jaw muscle activity. Better understanding has been acquired of bruxism relationships with sleep stages, arousal responses and autonomic function with the help of polysomnography and controlled sleep studies. Meanwhile, there is still much more to learn about awake bruxism. With the available scientific knowledge it is possible to systematically assess the effects of bruxism and its potential risk factors for oral and general health. Moreover, we can be aware of the realistic possibilities to manage/treat the patient suffering from bruxism. Conclusion Bruxism is a parafunctional activity involving the masticatory muscles and probably it is as old as human mankind. Different ways have been proposed to define, diagnose, assess the impact and consequences, understand the pathophysiology and treat or manage bruxism. Despite the vast research efforts made in this field, there are still significant gaps in our knowledge.


Asunto(s)
Bruxismo del Sueño/diagnóstico , Nivel de Alerta/fisiología , Humanos , Músculos Masticadores/fisiopatología , Polisomnografía/métodos , Factores de Riesgo , Sueño/fisiología , Bruxismo del Sueño/terapia , Fases del Sueño/fisiología , Vigilia/fisiología
10.
Implant Dent ; 25(1): 63-73, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26473440

RESUMEN

PURPOSE: The aim of the present study was to examine the osseointegration in low-density bone tissue for SLAffinity-treated implants with StemBios (SB) cell therapy. MATERIALS AND METHODS: The morphologies of SLAffinity-treated surfaces were characterized using scanning electron microscopy. In the animal model, implants were installed in the mandibular canine-premolar area of 12 miniature pigs. Each pig received 3 implants of machine, sand blasted, large grit, and acid etched, and SLAffinity-treated implants. In the clinical trial, 10 patients received 1 SLAffinity-treated implant in the maxilla in the posterior area and 1 patient with low bone tissue density received 2 SLAffinity-treated implants with SB cell therapy. Resonance frequency analysis and computed tomography were assessed monthly over the first 3 months after implant placement. RESULTS: The results demonstrated that surface treatment significantly affected early osseointegration in patients who received SB cell therapy. SB cell therapy transferred the stress caused by the implant more uniformly, and the stress decreased with healing time. SLAffinity-treated implants also proved clinically successful after the 3 months. CONCLUSION: The SLAffinity treatments enhanced osseointegration significantly, especially at early stages of bone tissue healing with SB cell therapy.


Asunto(s)
Implantación Dental Endoósea/métodos , Implantes Dentales , Trasplante de Células Madre/métodos , Adulto , Animales , Humanos , Microscopía Electrónica de Rastreo , Nanoestructuras , Propiedades de Superficie , Porcinos , Porcinos Enanos
11.
J Mater Sci Mater Med ; 26(2): 77, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25631273

RESUMEN

The aim of the present study was to investigate the thermal injury in the liver after a minimally invasive electrosurgery technique with a copper-doped diamond-like carbon (DLC-Cu) surface coating. To effectively utilize electrosurgery in a clinical caner setting, it is necessary to suppress the thermal injury to adjacent tissues. The surface morphologies of DLC-Cu thin films were characterized using scanning electron microscopy and transmission electron microscopy. Three-dimensional liver models were reconstructed using magnetic resonance imaging to simulate the electrosurgical procedure. Our results indicated that the temperature decreased significantly when minimally electrosurgery with nanostructured DLC-Cu thin films was used, and that it continued to decrease with increasing film thickness. In an animal model, thermography revealed that the surgical temperature was significantly lower in the minimally invasive electrosurgery with DLC-Cu thin film (DLC-Cu-SS) compared to untreated electrosurgery. In addition, DLC-Cu-SS created a relatively small thermal injury area and lateral thermal effect. These results indicated that the biomedical nanostructure coating reduced excessive thermal injury, and uniformly distributed temperature in the liver.


Asunto(s)
Quemaduras por Electricidad/prevención & control , Electrocirugia/instrumentación , Hepatectomía/instrumentación , Hígado/cirugía , Procedimientos Quirúrgicos Mínimamente Invasivos/instrumentación , Nanotecnología/instrumentación , Animales , Quemaduras por Electricidad/etiología , Quemaduras por Electricidad/patología , Electrocirugia/efectos adversos , Transferencia de Energía , Diseño de Equipo , Análisis de Falla de Equipo , Hepatectomía/efectos adversos , Calor , Hígado/lesiones , Hígado/patología , Neoplasias Hepáticas/patología , Neoplasias Hepáticas/cirugía , Procedimientos Quirúrgicos Mínimamente Invasivos/efectos adversos , Nanodiamantes/química , Ratas Sprague-Dawley , Conductividad Térmica , Cicatrización de Heridas
12.
ScientificWorldJournal ; 2015: 373149, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26380359

RESUMEN

The aim of the study was to investigate the long-term (one year) effectiveness of a 12-session weekly cognitive behavior group therapy (CBGT) on patients with depression. This was a single-blind randomized controlled study with a 2-arm parallel group design. Eighty-one subjects were randomly assigned to 12 sessions intervention group (CBGT) or control group (usual outpatient psychiatric care group) and 62 completed the study. The primary outcome was depression measured with Beck Depression Inventory (BDI-II) and Hamilton Rating Scale for Depression (HRSD). The secondary outcomes were automatic thoughts measured by automatic thoughts questionnaire (ATQ). Both groups were evaluated at the pretest (before 2 weeks), posttest (after 12 therapy sessions), and short- (3 months), medium- (6 months), and long-term (12 months) follow-up. After receiving CBGT, the experimental group had a statistically significant reduction in the BDI-II from 40.30 at baseline to 17.82 points at session eight and to 10.17 points at postintervention (P < 0.001). Similar effects were seen on the HRSD. ATQ significantly decreased at the 12th session, 6 months after sessions, and 1 year after the sessions ended (P < 0.001). We concluded that CBGT is effective for reducing depression and continued to be effective at 1 year of follow-up.


Asunto(s)
Terapia Cognitivo-Conductual/métodos , Depresión/terapia , Psicoterapia de Grupo/métodos , Adulto , Atención Ambulatoria , Cognición , Depresión/fisiopatología , Depresión/psicología , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Inventario de Personalidad , Escalas de Valoración Psiquiátrica , Método Simple Ciego , Encuestas y Cuestionarios , Resultado del Tratamiento
13.
Implant Dent ; 24(4): 441-7, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25946663

RESUMEN

OBJECTIVES: SLAffinity is the hybrid topography consisting of micropits and nanoporous TiO2 layers through electrochemical oxidation to mimic the natural bony environment. The aim of this study was to examine the rate of osseointegration in animal models and to further investigate the stability for implants with SLAffinity-treated surface in the clinical trial. MATERIALS AND METHODS: Implants were installed in the mandibular canine-premolar area of 12 miniature pigs. Each pig received 2 implants with the same shapes but with different chemical surfaces. In the clinical trial, 25 patients were included. Each patient received 1 SLAffinity-treated implant on the posterior area of either arch. Resonance frequency analysis and computed tomography were assessed weekly over the first 12 weeks after implant placement. RESULTS: The results found that surface treatment did affect the bone-to-implant contact (BIC) significantly. Comparison of BIC at 3 weeks in animal study showed that the SLAffinity-treated implants presented significantly higher values than machine surface implants. SLAffinity-treated implants also proved clinically successful through 12 months, ready for prosthodontic restoration. CONCLUSION: The effect of SLAffinity treatments enhanced osseointegration significantly, especially at early stages of bone healing. Clinical trial finding, furthermore, ensured that the SLAffinity treatment was a reliable surface modification alternative.


Asunto(s)
Implantación Dental Endoósea/instrumentación , Implantación Dental Endoósea/métodos , Implantes Dentales , Diseño de Prótesis Dental , Oseointegración/fisiología , Propiedades de Superficie , Adulto , Animales , Materiales Biocompatibles , Densidad Ósea , Modelos Animales de Enfermedad , Femenino , Humanos , Implantes Experimentales , Masculino , Porcinos , Porcinos Enanos , Titanio , Tomografía Computarizada por Rayos X
14.
Biochim Biophys Acta ; 1828(8): 1794-801, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23562405

RESUMEN

Recently, the structure-function relationships between amphotericin B (AmB) and ergosterol have been solved using synthetic techniques that require a mycosamine-mediated direct binding interaction between AmB and ergosterol to form AmB ion channels. However, studies to directly probe the AmB-induced membrane permeability changes have not been conducted. In the present work, we investigate the following fundamental question: does AmB induce concentration- and time-dependent permeability changes across ergosterol-containing membranes? Herein, we employ fluorescent dyes of known average diameter to quantify the diameters of AmB ion channels. In addition, we take a single-particle tracking approach to define the intracellular microrheology in the absence and presence of AmB ion channels. Present results show that increasing AmB concentration tends to increase the preferential accumulation of AmB ion channels in the presence of the excess membrane-embedded ergosterol. We found that AmB induces time-dependent membrane permeability; increases approaching 50% in both the velocity fluctuations and diffusion coefficients of vesicles occur on the same time scale as the efflux of potassium ions (≅30min). Furthermore, we propose a two-dimensional, semi-regular tessellation model to geometrically assess the pore size of the AmB ion channels in response to the AmB dose. This approach offers one possibility for the design of AmB ion channels with tunable aqueous pore size, which could provide an opportunity to replace damaged membrane water channels of the aquaporin family in future applications.


Asunto(s)
Anfotericina B/farmacología , Permeabilidad de la Membrana Celular/efectos de los fármacos , Neoplasias del Colon/metabolismo , Canales Iónicos/metabolismo , Polyporaceae/química , Potasio/metabolismo , Agua/metabolismo , Neoplasias del Colon/tratamiento farmacológico , Humanos , Polyporaceae/metabolismo , Reología , Células Tumorales Cultivadas
15.
Surg Endosc ; 28(7): 2174-88, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24619328

RESUMEN

BACKGROUND: Thermal injury and tissue sticking, which influence wound remodeling, are major concerns in electrosurgery. In this study, the effect of lateral thermal injury caused by different electrosurgical electrodes on hepatic remodeling was investigated. METHODS: A monopolar electrosurgical unit equipped with untreated stainless steel (SS) and chromium nitride coated stainless steel (CrN-SS) electrodes was used to create lesions on the liver lobes of adult rats. Animals were sacrificed for evaluations at 0, 3, 7, and 28 days postoperatively. RESULTS: CrN-SS needles generated lower levels of sticking tissue, and the thermographs showed that recorded highest temperature in liver tissue from the CrN-SS needle group was significantly lower than in the SS needle group. The total injury area of livers treated with CrN-SS needles was significantly lower than livers treated with SS needles at each time point. Moreover, the CrN-SS needles caused a relatively smaller area of lateral thermal injury, a smaller area of fibrotic tissue, and a faster process of hepatic remodeling in rat liver than the SS needles. Immunofluorescence staining and Western blot analysis showed that rats treated with CrN-SS needles expressed lower levels of NF-κB and caspase-3 postoperatively. CONCLUSIONS: This study reveals that the plating of electrodes with a CrN film is an efficient method for improving the performance of electrosurgical units and should benefit wound remodeling. However, more tests must be performed to confirm these promising findings in human patients.


Asunto(s)
Materiales Biocompatibles Revestidos , Electrocirugia/instrumentación , Hígado/patología , Hígado/cirugía , Animales , Apoptosis , Western Blotting , Quemaduras/patología , Quemaduras/prevención & control , Caspasa 3/metabolismo , Compuestos de Cromo , Técnica del Anticuerpo Fluorescente , Hepatocitos/metabolismo , Etiquetado Corte-Fin in Situ , Hígado/metabolismo , FN-kappa B/metabolismo , Nanoestructuras , Neovascularización Fisiológica , Ratas Sprague-Dawley , Acero Inoxidable , Termografía , Adherencias Tisulares
16.
J Oral Maxillofac Surg ; 72(9): 1703.e1-1703.e10, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24836420

RESUMEN

PURPOSE: This study evaluated the osteogenetic capability of Ling Zhi-8 (LZ-8; a protein purified from traditional Chinese medicine [lingzhi]) compared with recombinant human bone morphogenic protein-2 (rhBMP-2) in a standardized bony defect using a rabbit sinus model. MATERIALS AND METHODS: Twelve male New Zealand white rabbits (18 to 24 weeks old, 3.3 to 3.8 kg) were included in the study. Implants of normal saline 0.1 mg, rhBMP-2 0.1 mg, and LZ-8 0.1 mg were each mixed with a uniform biodegradable polyurethane-based material (Nasopore). The implants were inserted in a standardized bony defect of the nasal bone created by a 2.5-mm trephine bur. The rabbits were sacrificed at 1, 2, 4, and 8 weeks postoperatively. Volume computerized tomographic and histomorphometric examinations were used to evaluate the quantity and quality of regenerated bone. RESULTS: At postoperative week 4, radiography showed that the new bone volume was significantly larger in the rhBMP-2 group compared with the LZ-8 group (P = .041) and the control group (P = .015). Histomorphometrically, better wound healing of the rhBMP-2 group was found during the healing phase compared with the other 2 groups. CONCLUSION: The biomaterial implants using rhBMP-2 and LZ-8 had good biocompatibility and osteogenetic capabilities in the rabbit sinus model. Bone healing in rhBMP-2-treated defects was excellent and showed a significant difference compared with LZ-8. However, LZ-8-treated defects also exhibited bone regeneration, and this traditional Chinese medicine may possess osteogenic potential. Further investigations of the mechanism and application of this protein in osteogenesis are needed.


Asunto(s)
Proteína Morfogenética Ósea 2/uso terapéutico , Medicamentos Herbarios Chinos/uso terapéutico , Proteínas Fúngicas/uso terapéutico , Hueso Nasal/cirugía , Enfermedades Nasales/cirugía , Osteogénesis/efectos de los fármacos , Factor de Crecimiento Transformador beta/uso terapéutico , Implantes Absorbibles , Animales , Materiales Biocompatibles/química , Densidad Ósea/efectos de los fármacos , Regeneración Ósea/efectos de los fármacos , Modelos Animales de Enfermedad , Portadores de Fármacos , Humanos , Imagenología Tridimensional/métodos , Masculino , Hueso Nasal/efectos de los fármacos , Neovascularización Fisiológica/efectos de los fármacos , Poliuretanos/química , Conejos , Proteínas Recombinantes/uso terapéutico , Factores de Tiempo , Tomografía Computarizada por Rayos X/métodos , Cicatrización de Heridas/efectos de los fármacos
17.
Implant Dent ; 23(6): 659-64, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25379663

RESUMEN

OBJECTIVE: The purpose of this study was to investigate osseointegration and bone stress resulted during the first 3 months after the installation of functional implants modified with bioactive oxide. METHODS: Several studies have investigated finite element models for dental implants; however, only a few have examined a model for the implants during different stages of osseointegration. In this study, mandible models were reconstructed using computer tomographic data, and bone qualities and stress distributions were investigated as well. RESULTS: Bone quality increased rapidly within the 3-month bone healing time. Data analysis indicated that the bone stresses increased with the progress of osseointegration, and the maximum stresses were obtained at the position around the first screw. CONCLUSION: The results confirmed that functional films could improve the biomechanical properties of the implants and promote the initial bone stability. Furthermore, potential clinical benefit can be obtained due to the inducing superior biomechanical behavior in dental implants.


Asunto(s)
Densidad Ósea/fisiología , Implantes Dentales , Oseointegración/fisiología , Óxidos/farmacología , Fenómenos Biomecánicos , Femenino , Análisis de Elementos Finitos , Estudios de Seguimiento , Humanos , Imagenología Tridimensional , Masculino , Propiedades de Superficie , Factores de Tiempo , Titanio/farmacología , Tomografía Computarizada por Rayos X , Cicatrización de Heridas/fisiología
18.
Implant Dent ; 23(1): 74-8, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24445919

RESUMEN

PURPOSE: This study developed calcium phosphate bone substitutes and their microstucture and in vitro cell response were evaluated in comparison with commercial hydroxyapatite (HA). MATERIALS: HA powder was ball-milled and then sintered to transfer into the calcium phosphate bulks (CPB). The density, hardness, and microstructure of the CPB were investigated. The viability and proliferation of MG63 osteoblast-like cells on the commercial HA and the CPB were evaluated. RESULTS: The x-ray diffraction confirmed that the CPB consisted of α-tricalcium phosphate (α-TCP), CaO, and HA. The hardness, density, and α-TCP-to-HA ratio of the CPB decreased when increasing the sintering duration. Cell tests demonstrated that the CPB exhibited an earlier cell-spread response than the commercial HA. CONCLUSIONS: This study demonstrated that a phase transformation of HA into α-TCP and CaO was achieved by sintering. The cell tests indicated that the CPB has favorable in vitro cellular performance, which implied that it presented potential as bone substitute.


Asunto(s)
Sustitutos de Huesos/metabolismo , Fosfatos de Calcio , Durapatita , Línea Celular Tumoral , Humanos , Osteoblastos/metabolismo , Difracción de Rayos X
19.
Int J Mol Sci ; 15(10): 17938-62, 2014 Oct 08.
Artículo en Inglés | MEDLINE | ID: mdl-25299693

RESUMEN

In the past few years, biomaterials technologies together with significant efforts on developing biology have revolutionized the process of engineered materials. Three dimensional (3D) in vitro technology aims to develop set of tools that are simple, inexpensive, portable and robust that could be commercialized and used in various fields of biomedical sciences such as drug discovery, diagnostic tools, and therapeutic approaches in regenerative medicine. The proliferation of cells in the 3D scaffold needs an oxygen and nutrition supply. 3D scaffold materials should provide such an environment for cells living in close proximity. 3D scaffolds that are able to regenerate or restore tissue and/or organs have begun to revolutionize medicine and biomedical science. Scaffolds have been used to support and promote the regeneration of tissues. Different processing techniques have been developed to design and fabricate three dimensional scaffolds for tissue engineering implants. Throughout the chapters we discuss in this review, we inform the reader about the potential applications of different 3D in vitro systems that can be applied for fabricating a wider range of novel biomaterials for use in tissue engineering.


Asunto(s)
Materiales Biocompatibles/química , Ingeniería de Tejidos , Materiales Biocompatibles/metabolismo , Microambiente Celular , Matriz Extracelular/química , Matriz Extracelular/metabolismo , Hidrogel de Polietilenoglicol-Dimetacrilato/química , Nanoestructuras/química , Polímeros/química , Polímeros/metabolismo , Impresión Tridimensional
20.
Front Neuroinform ; 18: 1320189, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38420133

RESUMEN

Introduction: Pain assessment is extremely important in patients unable to communicate and it is often done by clinical judgement. However, assessing pain using observable indicators can be challenging for clinicians due to the subjective perceptions, individual differences in pain expression, and potential confounding factors. Therefore, the need for an objective pain assessment method that can assist medical practitioners. Functional near-infrared spectroscopy (fNIRS) has shown promising results to assess the neural function in response of nociception and pain. Previous studies have explored the use of machine learning with hand-crafted features in the assessment of pain. Methods: In this study, we aim to expand previous studies by exploring the use of deep learning models Convolutional Neural Network (CNN), Long Short-Term Memory (LSTM), and (CNN-LSTM) to automatically extract features from fNIRS data and by comparing these with classical machine learning models using hand-crafted features. Results: The results showed that the deep learning models exhibited favourable results in the identification of different types of pain in our experiment using only fNIRS input data. The combination of CNN and LSTM in a hybrid model (CNN-LSTM) exhibited the highest performance (accuracy = 91.2%) in our problem setting. Statistical analysis using one-way ANOVA with Tukey's (post-hoc) test performed on accuracies showed that the deep learning models significantly improved accuracy performance as compared to the baseline models. Discussion: Overall, deep learning models showed their potential to learn features automatically without relying on manually-extracted features and the CNN-LSTM model could be used as a possible method of assessment of pain in non-verbal patients. Future research is needed to evaluate the generalisation of this method of pain assessment on independent populations and in real-life scenarios.

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