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1.
Nanotechnology ; 23(49): 495602, 2012 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-23150203

RESUMEN

A single crystal domain texture quality (a unique in-plane and out-of-plane crystalline orientation over a large area) ZnO nanostructure of a dense nanowire array on a thick film has been homogeneously synthesized on a-plane sapphire substrates over large areas through a one-step chemical vapor deposition (CVD) process. The growth mechanism is clarified: a single crystal [02(-)1] oriented ZnAl(2)O(4) buffer layer was formed at the ZnO film and the a-plane sapphire substrate interface via a diffusion reaction process during the CVD process, providing improved epitaxial conditions that enable the synthesis of the high crystalline quality ZnO nanowire array on a film structure. The high optoelectronic quality of the ZnO nanowire array on a film sample is evidenced by the free exitonic emissions in the low-temperature photoluminescence spectroscopy. A carrier density of ~10(17) cm(-3) with an n-type conductivity of the ZnO nanowire array on a film sample is obtained by electrochemical impedance analysis. Finally, the ZnO nanowire array on a film sample is demonstrated to be an ideal template for a further synthesis of a single crystal quality ZnO-ZnGa(2)O(4) core-shell nanowire array on a film structure. The fabricated ZnO-ZnGa(2)O(4) sample revealed an enhanced anticorrosive ability and photoelectrochemical performance when used as a photoanode in a photoelectrochemical water splitting application.


Asunto(s)
Electroquímica/instrumentación , Electrodos , Membranas Artificiales , Nanotubos/química , Fotoquímica/instrumentación , Óxido de Zinc/química , Cristalización/métodos , Luz , Ensayo de Materiales , Nanotubos/efectos de la radiación , Óxido de Zinc/efectos de la radiación
2.
J Biomed Mater Res A ; 110(4): 909-915, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-34866336

RESUMEN

Air leakage is one of the major complications related to pulmonary surgeries. To reduce this complication, we developed a decyl group (C10)-modified Alaska pollock gelatin (ApGltn) (C10-ApGltn) sealant and evaluated its practical performance against commercially available sealants, Beriplast® and DuraSeal®. C10-ApGltn was synthesized by reductive amination of the amino groups in ApGltn with decanal. C10-ApGltn was crosslinked with a poly(ethylene glycol)-based crosslinker to form a tissue sealant. The crosslinking time of the C10-ApGltn sealant was fast enough for curing on tissue and application as a spray system. Although the percent swelling of C10-ApGltn and DuraSeal was significantly greater than Beriplast, C10-ApGltn and DuraSeal exhibited excellent tissue sealing properties on pleura tissue under a long-term moist condition. Additionally, C10-ApGltn and DuraSeal did not cause severe inflammatory responses in a rat subcutaneous example. Therefore, C10-ApGltn sealant had comparable tissue sealing properties to DuraSeal under a moist condition, indicating the potential of C10-ApGltn sealant for pulmonary surgeries.


Asunto(s)
Gelatina , Adhesivos Tisulares , Animales , Gelatina/farmacología , Interacciones Hidrofóbicas e Hidrofílicas , Polietilenglicoles , Ratas , Adhesivos Tisulares/farmacología
3.
Eur J Cardiothorac Surg ; 62(5)2022 10 04.
Artículo en Inglés | MEDLINE | ID: mdl-36264129

RESUMEN

OBJECTIVES: Postoperative prolonged air leakage is a frequent complication following lung resection. We have shown the high adhesive quality of a newly developed sealant based on a hydrophobically modified Alaska pollock-derived gelatin (ApGltn) sealant in acute in vivo settings. The purpose of this study was to investigate the long-term efficacy and safety of ApGltn sealant using rats as a preclinical model. METHODS: An air leakage rat model with a 5-mm pleural defect was created, to which ApGltn sealant or fibrin sealant was applied. In both groups, the rats were evaluated on days 1, 7, 14 and 28. In the ApGltn sealant group, days 56 and 84 were added to evaluate absorption as sealant was still present on day 28. The number of rats in each subgroup was 4 (for a total of 40). Lung specimens and blood samples were obtained for histological and haematological assessment. RESULTS: No findings suggesting infection or air leakage were observed. ApGltn sealant was absorbed from day 56 to day 84. Histologically, although neutrophil and lymphocyte infiltrations on the lung side did not differ between groups, those on the sealant side were significantly less in the ApGltn sealant group. Blood sample tests revealed no significant findings suggesting inflammation or organ damage in either group. CONCLUSIONS: ApGltn sealant showed long-term sealing efficacy and safety with mild inflammation in a pulmonary air leakage rat model. ApGltn sealant is expected to be a safe and effective sealant for clinical applications.


Asunto(s)
Enfermedades Pulmonares , Adhesivos Tisulares , Ratas , Animales , Gelatina/uso terapéutico , Adhesivos Tisulares/uso terapéutico , Alaska , Inflamación , Adhesivo de Tejido de Fibrina/uso terapéutico
4.
Ann Thorac Surg ; 113(5): 1641-1647, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-34102175

RESUMEN

BACKGROUND: Postoperative prolonged air leakage is a frequent complication after lung resection. We have developed a new sealant based on a hydrophobically modified Alaska pollock-derived gelatin (ApGltn) sealant. The purpose of this study was to evaluate the adhesive strength of the ApGltn sealant in comparison with a fibrin sealant using a new spray system in ex vivo and in vivo models. METHODS: Pleural defects in ex vivo and in vivo porcine models were created, to which the ApGltn sealant or the fibrin sealant was applied. The pressure resistance was assessed with a stepwise increase in airway pressure to confirm air leakage from the sealing site. Tissue samples covered with each sealant were obtained for histologic assessment. RESULTS: In the ex vivo experiment, the leak pressures of the ApGltn sealant were significantly greater than those of the fibrin sealant (102.94 ± 15.6 cm H2O and 28.37 ± 5.1 cm H2O, respectively) (P < .01). In the in vivo experiment, the leak pressures of the ApGltn sealant were also significantly greater than those of the fibrin sealant (68.82 ± 18.04 cm H2O and 43.33 ± 7.13 cm H2O, respectively) (P = .043). The histologic examination confirmed that the ApGltn sealant adhered tightly to both the pleura and the surface of the pleural defect. CONCLUSIONS: The ApGltn sealant has sufficiently high adhesive quality in ex vivo and in vivo porcine lungs, which could be considered suitable and effective for use in the prevention of air leakage from the lungs.


Asunto(s)
Enfermedades Pulmonares , Adhesivos Tisulares , Alaska , Animales , Adhesivo de Tejido de Fibrina/uso terapéutico , Gelatina/uso terapéutico , Humanos , Porcinos , Adhesivos Tisulares/farmacología , Adhesivos Tisulares/uso terapéutico
5.
Surg Case Rep ; 7(1): 56, 2021 Feb 23.
Artículo en Inglés | MEDLINE | ID: mdl-33620526

RESUMEN

BACKGROUND: Bilateral empyema is rare and can be life-threatening. Few cases have ever been reported about bilateral empyema with fistula on both sides. We herein report a case of bilateral empyema with bilateral fistulae that was treated with a 2-stage operation. CASE PRESENTATION: The patient was a 40 year-old man with uncontrolled diabetes mellitus, severe emaciation and remarkably decayed teeth. On his admission, computed tomography showed bilateral pneumothorax and pleural effusion. Thoracentesis revealed a cream-colored purulent pleural effusion from both sides of the pleural cavity. Bilateral empyema with fistulae on both sides due to a ruptured lung abscess was diagnosed. 7 days after his administration, we performed the first surgery. There were 3 fistulae in the right lateral basal segment (S9), right posterior basal segment (S10), and left posterior basal segment (S10). At the first operation, the S9 fistula was directly sutured; however, the right S10 fistula could not be closed because the surrounding tissue was fragile. The left lung fistula was deep and crater-shaped; it was closed with the suturing of a plugged free muscle flap. At the second operation, the right S10 fistula was closed with the superimposition of a pedicled intercostal muscle flap. CONCLUSION: Patients with bilateral empyema tend to be with poor general condition and, therefore, less invasive treatments are required initially. Closure of fistulae is an essential process for the treatment of empyema with fistulae. We could manage the fistulae using several techniques with 2-stage operation. Although the efficacy of using a free intercostal muscle flap to close the fistula has not been adequately verified, it is simple and less invasive and, thus, might be a useful option in cases where the patient is too ill to undergo a more invasive operation or when the surgical approach should be done in a short time.

6.
Ann Thorac Surg ; 107(6): 1656-1662, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-30648542

RESUMEN

BACKGROUND: Air leakage still remains a major problem in lung resection despite the introduction of surgical sealants. We have developed a novel sealant based on hydrophobically modified Alaska pollock-derived gelatin (ApGltn), which showed high adhesive quality in vitro. In this study, we evaluated the adhesive quality and conformability of our ApGltn sealant compared with a fibrin sealant. METHODS: The adhesive quality of the sealants was evaluated using excised porcine lungs with ventilation. Pleural defects were created, to which the ApGltn sealant or fibrin sealant was applied. Pressure resistance was assessed using a stepwise increase of airway pressure. Conformability was evaluated by measuring the area of the sealant for its maximum conformity on the gradually inflated lung surface. RESULTS: Leak and burst pressures of the ApGltn sealant were significantly higher than those of the fibrin sealant (47.1 ± 10.5 cm H2O and 52.3 ± 9.4 cm H2O versus 33.9 ± 6.0 cm H2O and 37.5 ± 5.9 cm H2O, respectively). Maximum expansion areas of the ApGltn sealant and fibrin sealant were 2652.4 ± 324.6 mm2 and 1276.6 ± 323.5 mm2, respectively. The ApGltn sealant also showed higher adhesive quality and conformability compared with the fibrin sealant. Histological examination confirmed that the ApGltn sealant showed tight adhesion to the pleural surface, while a gap was observed with the fibrin sealant. CONCLUSIONS: The ApGltn sealant showed higher adhesive quality and conformability than the fibrin sealant in an excised porcine lung model. We expect that, in the future, the ApGltn sealant will be used for lung resections in clinical settings.


Asunto(s)
Adhesivo de Tejido de Fibrina , Pulmón/cirugía , Adhesivos Tisulares , Animales , Gelatina , Ensayo de Materiales , Porcinos
7.
J Oral Sci ; 61(2): 284-293, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31217377

RESUMEN

Bone marrow-derived mesenchymal stem cells (BMMSCs) remain the most widely used source of osteogenic cells in bone tissue engineering research. A cell-based treatment for alveolar ridge augmentation has received attention as an alternative to bone grafting. In the present study, BMMSC transplantation into tooth extraction sockets of C57BL/6J mice was evaluated for alveolar ridge regeneration. The first right maxillary molars were extracted, and then BMMSCs (PDGFRα+ Sca-1+ CD45- TER119- cells) isolated from femoral and tibial bone marrow were immediately transplanted into the extraction sockets. A control group underwent the same procedure except for BMMSC transplantation. Bone formation in the sockets was evaluated using micro-computed tomography and histological and immunohistochemical analyses. At 3 weeks, bone formation in the sockets was more advanced in the experimental group than in the control group. Histological analysis at 6 weeks after transplantation showed that the sockets in the experimental group also contained a greater quantity of bone marrow. Interestingly, socket bone mineral density was lower in the experimental group than in the control group at 6 weeks. These findings suggest that BMMSC transplantation accelerates bone healing and augments bone marrow formation in tooth extraction sockets.


Asunto(s)
Células Madre Mesenquimatosas , Animales , Médula Ósea , Regeneración Ósea , Ratones , Ratones Endogámicos C57BL , Extracción Dental , Alveolo Dental , Microtomografía por Rayos X
8.
J Cataract Refract Surg ; 44(2): 219-225, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29587977

RESUMEN

PURPOSE: To assess the long-term influence of surface light scattering and glistenings of hydrophobic acrylic (Acrysof), silicone, and poly(methyl methacrylate) (PMMA) intraocular lenses (IOLs) on visual function. SETTING: Eleven surgical sites, Japan. DESIGN: Retrospective case series. METHODS: Patients who had cataract surgery with implantation of a hydrophobic acrylic, silicone, or PMMA IOL from 1994 to 2000 were examined. Silicone and PMMA IOLs were not restricted to specific manufacturers or models. Patients were included if their corrected distance visual acuity (CDVA) within 3 months postoperatively (baseline CDVA) was 20/25 or better. The CDVA, contrast sensitivity, degree of surface light scattering measured with Pentacam densitometry, and glistening grades were recorded at the patient's latest visit. RESULTS: Of the eyes, 31 had a hydrophobic acrylic IOL, 37 a silicone IOL, and 30 a PMMA IOL. Surface light scattering and glistenings were significantly greater with the hydrophobic acrylic IOL than with silicone and PMMA IOLs (P < .0001). The CDVA at the latest visit as well as the changes in CDVA from the baseline to the latest visit did not differ between the IOLs and was unaffected by surface light scattering and glistenings, as was the contrast sensitivity. CONCLUSIONS: The hydrophobic acrylic IOL was associated with a significantly greater level of surface light scattering and glistenings than the silicone IOLs and PMMA IOLs 15 to 20 years postoperatively. However, the optical phenomena within the optics of the hydrophobic acrylic IOL did not influence the patients' visual function.


Asunto(s)
Implantación de Lentes Intraoculares , Lentes Intraoculares , Facoemulsificación , Dispersión de Radiación , Vacuolas , Agudeza Visual/fisiología , Resinas Acrílicas , Adulto , Anciano , Anciano de 80 o más Años , Sensibilidad de Contraste/fisiología , Femenino , Deslumbramiento , Humanos , Luz , Masculino , Persona de Mediana Edad , Polimetil Metacrilato , Estudios Retrospectivos , Elastómeros de Silicona , Factores de Tiempo
9.
Respir Med Case Rep ; 19: 187-189, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27812497

RESUMEN

We describe two cases in each of which a dental prosthesis, presenting as an endobronchial foreign body (FB), was successfully retrieved using a snare technique employing a flexible bronchoscope and fluoroscopy that enabled us to avoid the need for rigid bronchoscope and thoracotomy. In one case, the FB was peripherally lodged and bronchoscopically invisible. In the other case, the FB was observed in the right intermediate bronchus, but the grasping basket and forceps were unable to retrieve it. The combination of a flexible bronchoscope and fluoroscopy extended the application of the snare technique to bronchoscopically invisible FBs and facilitated placement of an encircling loop around the FB. Since dental prostheses are rigid and irregular in shape, the snare loop technique can be used. For patients in a stable condition with a dental prosthesis FB, using the snare technique with a flexible bronchoscope and fluoroscopy is a good option. We provide technical tips based on our experiences.

10.
J. Health Sci. Inst ; 20(1): 57-62, jan.-jun. 2002. ilus, tab, graf
Artículo en Portugués | LILACS | ID: lil-324042

RESUMEN

O objetivo deste estudo é avaliar e comparar através do uso de corante, a microinfiltraçäo na interface dente/núcleo metálico fundido em raízes de dentes bovinos anteriores superiores. A microinfiltraçäo é caracterizada pela passagem clinicamente indetectável das bactérias, fluídos, moléculas ou íons entre as paredes da cavidade ou conduto e o material restaurador. É fundamental para uma maior longevidade e sucesso clínico que a microinfiltraçäo seja minimizada. Para tanto, no caso de núcleos metálicos fundidos, a fim de apresentarem boa adaptaçäo e intimidades às paredes dos condutos radiculares preparados, devem ser obtidos de maneira a reproduzir exatamente aforma anatômica desses condutos. Os núcleos metálicos fundidos foram obtidos através de duas técnicas distintas: direta ou modelagem dos condutos com resina acrílica ativada quimicamente e indireta ou moldagem do conduto com silicona de condensaçäo. Neste trabalho, a cimentaçäo dos núcleos foi feita com cimento de fosfato de zinco. Os resultados mostraram maior infiltraçäo no grupo da técnica indireta comparado com a técnica direta, diferença estatísticamente significante.(au)


Asunto(s)
Animales , Bovinos , Filtración Dental , Técnica de Perno Muñón
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