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1.
Cell ; 173(6): 1468-1480.e9, 2018 05 31.
Artículo en Inglés | MEDLINE | ID: mdl-29731167

RESUMEN

The cell wall, a defining feature of plants, provides a rigid structure critical for bonding cells together. To overcome this physical constraint, plants must process cell wall linkages during growth and development. However, little is known about the mechanism guiding cell-cell detachment and cell wall remodeling. Here, we identify two neighboring cell types in Arabidopsis that coordinate their activities to control cell wall processing, thereby ensuring precise abscission to discard organs. One cell type produces a honeycomb structure of lignin, which acts as a mechanical "brace" to localize cell wall breakdown and spatially limit abscising cells. The second cell type undergoes transdifferentiation into epidermal cells, forming protective cuticle, demonstrating de novo specification of epidermal cells, previously thought to be restricted to embryogenesis. Loss of the lignin brace leads to inadequate cuticle formation, resulting in surface barrier defects and susceptible to infection. Together, we show how plants precisely accomplish abscission.


Asunto(s)
Arabidopsis/fisiología , Pared Celular/metabolismo , Lignina/metabolismo , Proteínas de Arabidopsis/metabolismo , Diferenciación Celular , Membrana Celular/metabolismo , Perfilación de la Expresión Génica , Regulación de la Expresión Génica de las Plantas , Mutación , NADPH Oxidasas/metabolismo , Plantas Modificadas Genéticamente/fisiología , Pseudomonas syringae , Propiedades de Superficie
2.
Clin Oral Investig ; 28(9): 471, 2024 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-39110259

RESUMEN

OBJECTIVE: Advances in mobile technology are helping with health management practices, and smart toothbrushes provide proper dental care by collecting and analyzing users' toothbrushing data. The purpose of this study is to assess the effect of a telemonitoring device on oral hygiene management in individuals with intellectual or developmental disabilities and its role in promoting oral health. MATERIALS AND METHODS: Participants were split into two groups: one initially using the telemonitoring device (telemonitoring device/manual toothbrush) and the other using it later (manual toothbrush/telemonitoring device), with a one-month washout period. The study compared plaque index, halitosis, changes in oral microbiota, and guardian questionnaire responses between the groups. RESULTS: In period 1, the QHI index score significantly decreased from 1.93 to 0.83 in the group using the remote monitoring device, compared to an increase from 1.75 to 2.01 in the manual toothbrush group. Additionally, toothbrushing frequency, time, and cooperation increased by 0.82 ± 0.60, 0.82 ± 1.16, and 1.09 ± 0.94, respectively, with initial telemonitoring device use. However, these measures decreased by -1.45 ± 0.68, -1.09 ± 0.70, and - 1.00 ± 1.00 after switching to a manual toothbrush, and decreased by -0.64 ± 0.67, -0.27 ± 1.19, and 0.09 ± 0.94 overall, respectively. However, there were no significant differences in oral microbiota between the groups at these different time points. CONCLUSIONS: The study shows that telemonitoring devices effectively reduce plaque index and improve toothbrushing frequency, time, and cooperation. However, these benefits decrease after switching to a manual toothbrush. Follow-up is needed to assess satisfaction and compliance with telemonitoring device use. CLINICAL RELEVANCE: Using telemonitoring devices in the oral health management of individuals with intellectual and developmental disabilities can improve their oral health quality.


Asunto(s)
Estudios Cruzados , Discapacidad Intelectual , Higiene Bucal , Cooperación del Paciente , Cepillado Dental , Humanos , Femenino , Masculino , Cepillado Dental/instrumentación , Higiene Bucal/instrumentación , Adulto , Encuestas y Cuestionarios , Discapacidades del Desarrollo , Índice de Placa Dental , Telemedicina/instrumentación , Persona de Mediana Edad , Halitosis/terapia
3.
J Oral Maxillofac Surg ; 79(7): 1422.e1-1422.e8, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-33667345

RESUMEN

Sensory dysfunction is the most serious complication that occurs after extracting lower third molars in close proximity to the inferior alveolar nerve (IAN). Even experienced surgeons have difficulties in avoiding nerve damage when the root is anatomically adjacent to the nerve canal. A useful method for reducing nerve damage during extraction is to perform orthodontic extrusion, in which the distance between the nerve and the root increased after applying an orthodontic force on the third molar while extruding the tooth. Here, we report the case of a 37-year-old female who presented with a partially erupted left lower third molar and risk of IAN nerve damage because of close anatomical proximity between the nerve and root. She underwent extraction using a miniscrew placed in the maxilla and a routine orthodontic mechanism using a cross-arch elastic band that induced a 3-mm vertical eruption in the impacted third molar without using complex orthodontic devices. In addition, tilting the dental axis to the lingual side resolved the proximity between the IAN and the tooth, thereby allowing extraction to proceed without major complications.


Asunto(s)
Diente Impactado , Traumatismos del Nervio Trigémino , Adulto , Femenino , Humanos , Mandíbula/cirugía , Nervio Mandibular , Tercer Molar/cirugía , Extrusión Ortodóncica , Extracción Dental/efectos adversos , Diente Impactado/cirugía
4.
J Nanosci Nanotechnol ; 19(7): 3755-3761, 2019 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-30764931

RESUMEN

Intercolloidal behaviors mediated by metal-ligand coordination have rarely been studied. In this work, such intercolloidal behaviors were demonstrated visibly using blue-colored polydiacetylene liposomes containing a phenolic lipid that acts as a binding ligand toward metal ions. The optimized liposomes were 150-200 nm in diameter and stable in aqueous solution. In incubation tests with various neocortical metal ions, iron(III) ions produced the most obvious colloidal aggregation of the liposomes. As the pH of the incubation medium was increased from acid to basic, stronger aggregation and increased precipitation behavior were observed. The phenolic lipid is believed to contribute to the interliposomal bridging interaction, and the pH dependence of the complexation between iron(III) and the phenolic lipid inserted in the liposomes were verified.


Asunto(s)
Compuestos Férricos , Liposomas , Concentración de Iones de Hidrógeno , Iones , Lípidos , Polímero Poliacetilénico
5.
J Clin Pediatr Dent ; 42(1): 50-54, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-28937892

RESUMEN

This case compared gene-expression between a new type of idiopathic gingival fibromatosis (IGF) and normal gingiva, to clarify the nature of the gingival overgrowth and dental anomaly. A 6-year-old girl with generalized gingival overgrowth and root deformations was diagnosed with IGF. Gene expression profiles were compared between normal gingiva (N=9) and one IGF gingiva using cDNA microarray. Genes related to regulation of cell proliferation and proteolytic degradation were expressed strongly in IGF. MMP-13 and MMP-12 expression were 120 times and 96 times lower in IGF, respectively, whereas AMBN expression was 79 times higher. RT-PCR and immunohistochemical staining supported the microarray results. Reduced proteolytic activity due to low MMP-13 and MMP-12 expression appears to be a potential mechanism for gingival overgrowth. Genetic investigations, such as expression levels of MMP-13, MMP-12, and AMBN, may enable classification of a new syndrome characterized by gingival enlargement with abnormal root development.


Asunto(s)
Proteínas del Esmalte Dental/genética , Fibromatosis Gingival/genética , Metaloproteinasa 12 de la Matriz/genética , Metaloproteinasa 13 de la Matriz/genética , Niño , Femenino , Humanos , Análisis de Secuencia por Matrices de Oligonucleótidos
6.
J Clin Pediatr Dent ; 42(5): 401-405, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30222510

RESUMEN

An ankylosed primary molar may cause rotation or ectopic impaction of succedaneous premolar. When conventional treatment modalities such as observation, surgical exposure with or without orthodontic traction, and autotransplantation are not possible, the simple surgical relocation method could be an alternative treatment option for a lingually rotated premolar during the tooth germ stage before opting to extraction. In the case reported herein, the lingually rotated permanent mandibular second premolar tooth germ was surgically relocated within its bony crypt. Continued root development and spontaneous eruption were observed without complications during the 3.5-year follow-up period.


Asunto(s)
Diente Premolar/cirugía , Anquilosis del Diente/cirugía , Germen Dentario/cirugía , Preescolar , Femenino , Humanos , Diente Primario
7.
J Clin Pediatr Dent ; 40(5): 388-92, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27617379

RESUMEN

OBJECTIVES: The aim of this study was to assess the validity of a new caries activity test that uses dental plaque acidogenicity in children with deciduous dentition. STUDY DESIGN: Ninety-two children under the age of three years old underwent clinical examination using the dft index and examinations with two caries activity tests. Plaque samples for the new Cariview(®) test and the saliva sample for the conventional Dentocult SM(®) test were collected, incubated, and scored according to each manufacturers' instruction. The data were analysed using ANOVA and Spearman correlation analyses to evaluate the relationships between the test results and the caries experience. RESULTS: The mean dft index of all of the subjects was 4.73, and 17.4% of the subjects were caries-free. The levels of caries risk based on the new Cariview test score significantly increased with the caries experience (p < 0.01). The test results revealed a stronger correlation with caries indices (dft and dt index) than the conventional SM colony counting method (r = 0.43, r = 0.39, p < 0.01). CONCLUSIONS: The new caries activity test to analyse the acidogenic potential of whole microorganisms from dental plaques can be used to evaluate caries risk in children with deciduous teeth.


Asunto(s)
Pruebas de Actividad de Caries Dental/métodos , Placa Dental/fisiopatología , Ácidos , Carga Bacteriana , Preescolar , Colorimetría/métodos , Estudios Transversales , Índice CPO , Pruebas de Actividad de Caries Dental/instrumentación , Susceptibilidad a Caries Dentarias , Placa Dental/microbiología , Femenino , Humanos , Concentración de Iones de Hidrógeno , Lactante , Masculino , Tiras Reactivas , Saliva/microbiología , Saliva/fisiología , Streptococcus mutans/aislamiento & purificación , Diente Primario/patología
8.
Calcif Tissue Int ; 97(1): 80-9, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25894066

RESUMEN

There have been many attempts to use the pulp tissue from human deciduous teeth for dentin or bone regeneration. The objective of this study was to determine the effects of odonto/osteogenic in vitro differentiation of deciduous teeth pulp stem cells (DTSCs) on their in vivo hard tissue-forming potential. DTSCs were isolated from extracted deciduous teeth using the outgrowth method. These cells were exposed to odonto/osteogenic stimuli for 4 and 8 days (Day 4 and Day 8 groups, respectively), while cells in the control group were cultured in normal medium. The in vitro differentiated DTSCs and the control DTSCs were transplanted subcutaneously into immunocompromised mice with macroporous biphasic calcium phosphate and sacrificed at 8 weeks post-implantation. The effect of odonto/osteogenic in vitro differentiation was evaluated using alkaline phosphatase (ALP) staining and quantitative reverse transcription polymerase chain reaction (RT-PCR). The in vivo effect was evaluated by qualitative RT-PCR, assessment of ALP activity, histologic analysis, and immunohistochemical staining. The amount of hard tissue was greater in Day 4 group than Day 8 group (p = 0.014). However, Day 8 group generated lamellar bone-like structure, which was immunonegative to anti-human dentin sialoprotein with significantly low expression level of DSPP compared with the control group (p = 0.008). This study demonstrates that odonto/osteogenic in vitro differentiation of DTSCs enhances the formation of bone-like tissue, instead of dentin-like tissue, when transplanted subcutaneously using MBCP as a carrier. The odonto/osteogenic in vitro differentiation of DTSCs may be an effective modification that enhances in vivo bone formation by DTSCs.


Asunto(s)
Regeneración Ósea/fisiología , Diferenciación Celular/fisiología , Pulpa Dental/citología , Osteogénesis/fisiología , Células Madre/citología , Diente Primario/citología , Animales , Proliferación Celular/fisiología , Células Cultivadas , Humanos , Ratones
9.
Cryobiology ; 71(3): 374-83, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26506257

RESUMEN

The aim of this study is to compare the characteristics of stem cells derived from human exfoliated deciduous teeth (SHED) from cryopreserved intact deciduous teeth with those of fresh SHED. In total, 20 exfoliated deciduous teeth were randomly divided into a fresh group (f-SHED; n = 11) and cryopreserved group (c-SHED; n = 9; stored for 1-8 months). Following thawing and separation of the pulp, the SHED cells were cultured, and the characteristics as mesenchymal stem cells were investigated using proliferation assays, cell-cycle analysis, colony-forming unit-fibroblast (CFU-F) assays, and flow cytometry analyses. Furthermore, differentiation into adipogenic and osteogenic lineages was investigated in vitro as well as in vivo via transplantation in mice. We found no significant differences between the two groups in the proliferation analyses, in the expression of mesenchymal stem cell markers, or in the adipogenic and osteogenic differentiation in vitro (p < 0.05). Furthermore, the in vivo transplantation results showed no significant differences in the quantity of bone tissue that formed or in histochemistry performance (p < 0.05). In conclusion, cryopreservation of intact exfoliated deciduous teeth appears to be a useful method for preserving SHED.


Asunto(s)
Criopreservación/métodos , Células Madre/citología , Diente Primario/citología , Animales , Diferenciación Celular , Citometría de Flujo , Humanos , Ratones
10.
Cell Tissue Bank ; 16(3): 361-9, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25407534

RESUMEN

The aim of this study was to confirm the osteoconduction capacities and determine the potential of permanent teeth ash (PTA), and deciduous teeth ash (DTA) as bone substitutes. Rats (n = 71) were divided randomly into four groups: sham, micro macroporous biphasic calcium phosphate (MBCP), PTA, and DTA. A sample of the each group was transplanted into preformed 8-mm calvarial defects (one per rat). The density of new bone was calculated and the crystallinities of the PTA and DTA were analyzed by X-ray diffraction. The degree of new bone formation was high in the MBCP and DTA groups but low in the PTA groups. The DTA was highly crystalline, whereas the PTA was not. The percentages of ß-tricalcium phosphate in the DTA and PTA were 10.7 and 3.7%, respectively. DTA has a high osteoconduction capacity, suggesting that it is a useful bone substitute.


Asunto(s)
Regeneración Ósea/fisiología , Sustitutos de Huesos/uso terapéutico , Minerales/uso terapéutico , Fracturas Craneales/patología , Fracturas Craneales/cirugía , Diente Primario/química , Animales , Sustitutos de Huesos/química , Trasplante Óseo/métodos , Dentición Permanente , Humanos , Masculino , Radiografía , Ratas , Ratas Sprague-Dawley , Fracturas Craneales/diagnóstico por imagen , Resultado del Tratamiento
11.
Biochem Biophys Res Commun ; 447(3): 400-6, 2014 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-24727454

RESUMEN

The umbilical cord blood (UCB) cells have been reported to secrete therapeutic signals, including a series of neurotrophic factors. This suggests the cell source provides suitable therapeutic environments for nerve regeneration that ultimately finds a possible cell therapy for nerve tissue. In this study, we observe a collagen hydrogel provides human UCB cells a proper 3D environment that stimulates the release of various neurotrophic factors. When compared to 2D culture, the 3D hydrogel culture significantly enhanced the expression of a series of neurotrophic factors, including neurotrophins, nerve growth factor, brain-derived neurotrophic factor, and ciliary neurotrophic factor as verified by the gene and protein analysis. To confirm the effects of neurotrophic factors secretion, we allowed an indirect interaction of the UCB-environment with human neural precursor cells (hNPCs). Results showed significantly enhanced neurite outgrowth of hNPCs. Collectively, our findings demonstrate that the collagen-based 3D hydrogel provides excellent environment for UCB-derived cells to release neurotrophic factors that will be ultimately useful for the neural repair and regeneration purposes.


Asunto(s)
Colágeno/farmacología , Sangre Fetal/efectos de los fármacos , Hidrogel de Polietilenoglicol-Dimetacrilato/farmacología , Factores de Crecimiento Nervioso/metabolismo , Células-Madre Neurales/fisiología , Neuritas/fisiología , Células Cultivadas , Microambiente Celular , Técnicas de Cocultivo , Sangre Fetal/metabolismo , Citometría de Flujo , Humanos , Factores de Crecimiento Nervioso/genética
12.
Cell Tissue Bank ; 15(1): 67-74, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23670172

RESUMEN

The cryopreservation of exfoliated deciduous teeth and harvesting of stem cells from them as required would reduce the costs and efforts associated with banking stem cells from primary teeth. The aim of this study was determine whether the viability of pulp stromal cells from deciduous teeth was influenced by the cryopreservation process itself or the period of cryopreservation. In total, 126 deciduous teeth were divided into three groups: (1) fresh, (2) cryopreserved for <3 months (cryo<3), and (3) cryopreserved for 3-9 months (cryo3-9). The viability of the pulp tissues was compared among the three groups by evaluating the outgrowth from pulp tissues and cell activity within those pulp tissues. In addition, the terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling (TUNEL) assay was performed to compare cell apoptosis within fresh pulp tissue and pulp tissue that had been cryopreserved for 4 months. The outgrowth from and cell activity within the pulp tissues did not differ significantly between the fresh and cryo<3 pulp tissues. However, these parameters were significantly reduced in the cryo3-9 pulp tissue. In TUNEL assay, 4-month cryopreserved pulp tissues has more apoptotic cells than fresh group. In conclusion, it is possible to acquire pulp stromal cells from cryopreserved deciduous teeth. However, as the period of cryopreservation becomes longer, it is difficult to get pulp cells due to reduced cell viability.


Asunto(s)
Criopreservación , Pulpa Dental/citología , Células Madre/citología , Células del Estroma/citología , Diente Primario/citología , Adolescente , Apoptosis , Diferenciación Celular , Separación Celular , Supervivencia Celular/fisiología , Células Cultivadas , Niño , Preescolar , Femenino , Humanos , Etiquetado Corte-Fin in Situ , Masculino
13.
J Clin Pediatr Dent ; 38(4): 362-5, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25571690

RESUMEN

Dentinogenesis imperfecta (DGI) is a hereditary defect consisting of opalescent teeth composed of irregularly formed and hypomineralized dentin. This paper presents the multiple fractures of DGI-affected teeth and suggests the reason of low fracture resistance by observing the dentin microstructures directly using scanning electron microscope (SEM) and by measuring its surface hardness using the Vickers hardness test. SEM revealed that while the enamel microstructure was similar in the DGI-affected and normal teeth, the microstructure of the DGI-affected dentin was poorly woven and more loosely packed than that of the normal dentin. The Vickers hardness of the DGI-affected dentin was 4.89 times softer than the normal dentin. The low fracture resistance of DGI-affected teeth can be attributed to the poorly woven microstructure of their dentin, which leads to a reduction in hardness.


Asunto(s)
Dentinogénesis Imperfecta/complicaciones , Fracturas de los Dientes/etiología , Niño , Cristalografía , Esmalte Dental/ultraestructura , Dentina/ultraestructura , Durapatita/química , Dureza , Humanos , Masculino , Microscopía Electrónica de Rastreo , Diente Molar/anomalías , Diente Molar/ultraestructura
14.
Environ Pollut ; 358: 124433, 2024 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-38925216

RESUMEN

Wastewater treatment plants (WWTPs) are considered a significant microplastic discharge source. To evaluate the amount and characteristics of microplastics discharged from WWTPs in South Korea, we selected 22 municipal WWTPs nationally and investigated microplastics at each treatment stage. The mean microplastic removal efficiency by WWTPs was >99%, and most of the microplastics were removed by sedimentation with the second clarifier during wastewater treatment. Consequently, the microplastic removal efficiency of WWTPs did not significantly differ from that of the adopted wastewater treatment technology because a second clarifier was applied in most WWTPs. However, for WWTPs operating a tertiary treatment process, the removal efficiency was enhanced compared with that of WWTPs discharging after a second clarifier. Although the microplastic removal efficiency was high by WWTP, the discharge contribution to the water environment could not be ignored because of the amount of treated wastewater, resulting in an increase of 5.8-270.9 items/m3 of microplastics in the receiving water. The characteristics of microplastics in WWTPs, including their components, shape, and size, were also evaluated. The most detected components included polytetrafluoroethylene and polyester. Most microplastics detected were categorized as fragments and fibers, while other types were hardly detected. The size of more than 70% of the microplastics detected in WWTPs was under 300 µm, implying that the size of microplastics required to control in WWTPs was much smaller than the defined size of microplastics. An evaluation of the correlation between other pollution factors and microplastic abundance did not reveal positive correlations, and microplastic occurrence was not affected by changing seasons, which may need to be evaluated with further studies. Research should also be performed on the effect of influent sources on the level of microplastic abundance and fate of ultrafine plastics in WWTPs.


Asunto(s)
Monitoreo del Ambiente , Microplásticos , Eliminación de Residuos Líquidos , Aguas Residuales , Contaminantes Químicos del Agua , República de Corea , Microplásticos/análisis , Aguas Residuales/química , Contaminantes Químicos del Agua/análisis , Monitoreo del Ambiente/métodos
15.
Sci Rep ; 14(1): 2089, 2024 01 24.
Artículo en Inglés | MEDLINE | ID: mdl-38267499

RESUMEN

This study investigated natal factors influencing developmental defects of enamel (DDE) in premature infants using a newly refined preterm developmental defects of enamel (PDDE) index. Dental examinations were conducted on a cohort of 118 preterm infants (average age 3.5 ± 1.4 years) to record PDDE scores, while reviewing their medical records to examine natal factors. According to the logistic regression analysis, factors related to DDE prevalence were advanced maternal age, gestational age < 28 weeks, birth weight < 1000 g, 1 min APGAR score < 7, and hospitalization period > 2 months, which were significantly higher by 2.91, 5.53, 7.63, 10.02, and 4.0 times, respectively. According to regression analysis with generalized linear models, the PDDE scores were approximately 7.65, 4.96, and 15.0 points higher in premature children diagnosed with bronchopulmonary dysplasia, intraventricular hemorrhage, and necrotizing enterocolitis, respectively. When endotracheal intubation was performed, the PDDE score was 5.06 points higher. The prevalence of PDDE was primarily observed bilaterally in the maxillary anterior teeth. Extremely preterm infants showed significantly delayed tooth eruption, suggesting that the influence of gestational age on dental development rates. Identifying the factors related to DDE in premature children can inform early dental interventions to support the oral health of high-risk children.


Asunto(s)
Defectos del Desarrollo del Esmalte , Nacimiento Prematuro , Niño , Lactante , Femenino , Humanos , Recién Nacido , Preescolar , Estudios Prospectivos , Edad Gestacional , Recien Nacido Extremadamente Prematuro
16.
J Liposome Res ; 23(4): 336-42, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23879241

RESUMEN

The radiolabeling of the liposome surface can be a useful tool for in vivo tracking of therapeutic drug loaded liposomes. We investigated radiolabeling therapeutic drug (i.e. an antibiotic, amikacin) loaded liposomes with (99m)Tc, nebulization properties of (99m)Tc-labeled liposomal amikacin for inhalation ((99m)Tc-LAI), and its stability by size exclusion low-pressure liquid chromatography (LPLC). LAI was reacted with (99m)Tc using SnCl2 dissolved in ascorbic acid as a reducing agent for 10 min at room temperature. The labeled products were then purified by anion exchange resin. The purified (99m)Tc-LAI in 1.5% NaCl solution was incubated at 4 °C to assess its stability by LPLC. The purified (99m)Tc-LAI was subjected to studies with a clinically used nebulizer (PARI eFlow®) and the Anderson Cascade Impactor (ACI). The use of ascorbic acid at 0.91 mM resulted in a quantitative labeling efficiency. The LPLC profile showed that the liposomal peak of LAI detected by a UV monitor at both 200 nm and 254 nm overlapped with the radioactivity peak of (99m)Tc-LAI, indicating that (99m)Tc-LAI is suitable for tracing LAI. The ACI study demonstrated that the aerosol droplet size distribution determined gravimetrically was similar to that determined by radioactivity. The liposome surface labeling method using SnCl2 in 0.91 mM ascorbic acid produced (99m)Tc-LAI with a high labeling efficiency and stability that are adequate to evaluate the deposition and clearance of inhaled LAI in the lung by gamma scintigraphy.


Asunto(s)
Amicacina/administración & dosificación , Antibacterianos/administración & dosificación , Liposomas , Compuestos de Organotecnecio/química , Administración por Inhalación , Amicacina/química , Antibacterianos/química , Cromatografía en Gel , Cromatografía Líquida de Alta Presión , Tamaño de la Partícula , Espectrofotometría Ultravioleta
17.
J Dent ; 137: 104684, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37660882

RESUMEN

OBJECTIVES: This study aimed to verify the non-inferiority of Endocem MTA Premixed and Well-Root PT, compared with ProRoot MTA in the pulpotomy of primary molars. In addition, we tried to determine the factors that affect the prognosis of pulpotomy in primary molars. METHODS: This randomized clinical trial enrolled 158 molars of 52 children; 153 teeth were finally included and divided into three groups: ProRoot MTA (n = 50), Endocem MTA Premixed (n = 53), and Well-Root PT (n = 50). Clinical and radiographic follow-up was performed at 3, 6, and 12 months postoperatively and at the last visit post-treatment. Data were analyzed using the Fisher's exact test, Cox regression analysis, and the Kaplan-Meier survival curve method. RESULTS: The success rates in the ProRoot MTA, Endocem MTA Premixed, and Well-Root PT were 92, 84.9 and 82%, respectively. The cumulative survival rates did not differ significantly among the materials. Among the investigated variables, only ΔF and ΔF max significantly affected the success rates. In the multivariate survival tree model, significant unfavorable survival was observed when the ΔF value was -14.4 or less (hazard ratio, 7.56; P = 0.0295). CONCLUSIONS: Considering the clinical effectiveness of Endocem MTA Premixed and Well-Root PT and the operational convenience as a premixed type, they can be used as advantageous materials in the pulpotomy of primary molars in pediatric patients. The QLF method is a useful diagnostic method that can establish treatment plans and determine the prognosis of pulpotomy based on the ΔF value in primary molars. CLINICAL SIGNIFICANCE: Endocem MTA Premixed and Well-Root PT can confer high success rates and are non-inferior to ProRoot MTA in pulpotomy for primary molars. We also showed that QLF technology can be applied to predict the success/failure and prognosis of pulpotomies in primary molars.


Asunto(s)
Cemento Dental , Pulpotomía , Humanos , Niño , Compuestos de Calcio/uso terapéutico , Diente Molar/diagnóstico por imagen , Diente Molar/cirugía
18.
Environ Pollut ; 333: 122017, 2023 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-37307864

RESUMEN

Large amounts of microplastics are discharged into wastewater treatment plants (WWTPs), from where some of them are released into natural waterbodies on account of their not being fully eliminated by WWTPs. To investigate the behavior and emission of microplastics from WWTPs, we selected four WWTPs with different treatment technologies, including anaerobic-anoxic-aerobic (A2O), sequence batch reactor (SBR), media, and membrane bioreactor (MBR). The number of microplastics detected using Fourier transform infrared (FT-IR) spectroscopy ranged from 520 to 1820 particles/L in influent and from 0.56 to 2.34 particles/L in effluent. The microplastic removal efficiencies of four WWTPs were over 99%, indicating that the type of treatment technologies did not significantly affect the removal rate of microplastics. In the unit process for each WWTP, the major stages relating to microplastic removal were the secondary clarifier and tertiary treatment processes. Most microplastics detected were categorized as fragments and fibers, while other types were hardly detected. The size of more than 80% of microplastic particles detected in WWTPs ranged between 20 and 300 µm, indicating that they were significantly smaller than the size threshold defined for microplastics. Therefore, we used thermal extraction-desorption coupled with gas chromatography-mass spectroscopy (TED-GC-MS) to evaluate the microplastic mass content in all four WWTPs, and the results were compared with those of the FT-IR analysis. In this method, only four components, namely polyethylene, polypropylene, polystyrene, and polyethylene terephthalate, were analyzed because of the analysis limitation, and the total microplastic concentration represented the sum of four components concentrations. The influent and effluent microplastic concentrations estimated by TED-GC-MS ranged from not detectable to 160 µg/L and 0.04-1.07 µg/L, respectively, indicating a correlation coefficient of 0.861 (p < 0.05) between the TED-GC-MS and FT-IR results, when compared to the combined abundance of the four microplastic components by FT-IR analysis.


Asunto(s)
Contaminantes Químicos del Agua , Purificación del Agua , Microplásticos , Plásticos/análisis , Aguas Residuales , Espectroscopía Infrarroja por Transformada de Fourier , Análisis de Fourier , Cromatografía de Gases y Espectrometría de Masas , Contaminantes Químicos del Agua/análisis , Monitoreo del Ambiente , Eliminación de Residuos Líquidos
19.
Biomacromolecules ; 13(10): 3388-94, 2012 Oct 08.
Artículo en Inglés | MEDLINE | ID: mdl-22970880

RESUMEN

Biopolymers bearing hydrophobic side-chains, such as hydrophobically modified chitosan (hmC), can connect liposomes into a gel network via hydrophobic interactions. In this paper, we show that such liposome gels possess an attractive combination of properties for certain drug delivery applications. Their shear-thinning property allows these gels to be injected at a particular site, while their gel-like nature at rest ensures that the material will remain localized at that site. Moreover, drugs can be encapsulated in the interior of the liposomes and delivered at the local site for an extended period of time. The presence of two transport resistances - from the liposomal bilayer and the gel network - is shown to be responsible for the sustained release; in turn, disruption of the liposomes both weakens the gel and causes a faster release. We have monitored release kinetics from liposome gels of a cationic anticancer drug doxorubicin (Dox) encapsulated in liposomes. Sustained release of Dox from these gels and the concomitant cytotoxic effect could be observed for over a week.


Asunto(s)
Antineoplásicos/farmacología , Biopolímeros/farmacología , Quitosano/farmacología , Sistemas de Liberación de Medicamentos , Liposomas/farmacología , Antineoplásicos/química , Biopolímeros/química , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Quitosano/química , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Geles/química , Geles/farmacología , Humanos , Interacciones Hidrofóbicas e Hidrofílicas , Liposomas/química , Estructura Molecular , Reología , Relación Estructura-Actividad
20.
J Mater Sci Mater Med ; 23(9): 2203-15, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22714559

RESUMEN

The number of metallic implantable devices placed every year is estimated at 3.7 million. This number has been steadily increasing over last decades at a rate of around 8 %. In spite of the many successes of the devices the implantation of biomaterial into tissues almost universally leads to the development of an avascular sac, which consists of fibrous tissue around the device and walls off the implant from the body. This reaction can be detrimental to the function of implant, reduces its lifetime, and necessitates repeated surgery. Clearly, to reduce the number of revision surgeries and improve long-term implant function it is necessary to enhance device integration by modulating cell adhesion and function. In this paper we have demonstrated that it is possible to enhance stem cell attachment using engineered biointerfaces. To create this functional interface, samples were coated with polymer (as a precursor) and then ion implanted to create a reactive interface that aids the binding of biomolecules--fibronectin. Both AFM and XPS analyses confirmed the presence of protein layers on the samples. The amount of protein was significant greater for the ion implanted surfaces and was not disrupted upon washing with detergent, hence the formation of strong bonds with the interface was confirmed. While, for non ion implanted surfaces, a decrease of protein was observed after washing with detergent. Finally, the number of stem cells attached to the surface was enhanced for ion implanted surfaces. The studies presented confirm that the developed bionterface with immobilised fibronectin is an effective means to modulate stem cell attachment.


Asunto(s)
Fibronectinas/uso terapéutico , Prótesis e Implantes , Células Madre/citología , Células Madre/fisiología , Ingeniería de Tejidos/métodos , Absorción , Adhesividad/efectos de los fármacos , Animales , Adhesión Celular/efectos de los fármacos , Comunicación Celular/efectos de los fármacos , Comunicación Celular/fisiología , Células Cultivadas , Materiales Biocompatibles Revestidos/síntesis química , Materiales Biocompatibles Revestidos/química , Materiales Biocompatibles Revestidos/metabolismo , Fibronectinas/genética , Fibronectinas/metabolismo , Fibronectinas/farmacología , Níquel/química , Níquel/metabolismo , Unión Proteica , Ratas , Células Madre/metabolismo , Propiedades de Superficie , Titanio/química , Titanio/metabolismo , Humectabilidad/efectos de los fármacos
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