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1.
Int J Biol Macromol ; 270(Pt 1): 132298, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38750863

RESUMEN

Microcrystalline cellulose (MCC) is one of the essential functional excipients in the formulation of tablets. The need for cheaper MCC sources has drawn significant attention to exploring renewable sources. In this study, MCC was produced from soybean hull (SBH), the primary by-product of the soy industry, using a novel, simplified, and cost-effective approach. Various characterization techniques were used to study the physicochemical properties and micromeritics of the SBH-based MCC powders and compare them to those of the commercial Avicel PH-101. SBH MCCs had a larger particle size, a broader particle size distribution, a higher degree of polymerization, a higher degree of crystallinity, better thermal stability, and slightly superior flowability and compressibility than Avicel PH-101. The tableting blends (containing 60 % MCC) were prepared, and the post-compression out-of-die Heckel analysis showed that formulations with aggregated SBH MCCs were less ductile than those made with Avicel PH-101, resulting in a lower porosity (better compressibility) of the latter at higher compression pressures. The hardness values for all formulations were above 6 kg, with higher values for those made with Avicel PH-101. The lubricant sensitivity was lower for SBH MCCs. All tablets made using developed formulations showed very low friability (<0.1 %) and short disintegration times (<90 s), making them well-suited candidates for manufacturing orally disintegrating tablets (ODTs).


Asunto(s)
Celulosa , Excipientes , Glycine max , Polvos , Comprimidos , Celulosa/química , Glycine max/química , Excipientes/química , Tamaño de la Partícula , Composición de Medicamentos/métodos
2.
Sci Rep ; 13(1): 19350, 2023 Nov 07.
Artículo en Inglés | MEDLINE | ID: mdl-37935797

RESUMEN

Traditionally, cellulose nanofiber (CNF) production has primarily relied on virgin cellulose sources. Yet, the shift to using paper mill sludge (PMS) as a source for CNF underscores the significance of reusing and recycling industrial byproducts. PMS contains significant amounts of cellulose that can be extracted as a raw material. The purpose of present study is to provide a sustainable approach to PMS utilization as a paper coating additive in the cellulose nanofibrils (CNFPMS) form via simply scalable wire-wound rod coating method. The effect of CNFPMS additive amounts at two coating layers on microstructure and surface properties of coatings such as porosity, air permeability surface roughness and optical properties such as brightness, gloss and CIE L*a*b* is studied, which they can also provide insight for the eventual print performance. Results indicated that the obtained CNFPMS in paper coating shows 52% decrease in porosity, presenting significant improvement in the coating microstructure. The marginal increase in permeability coefficient and surface roughness, 54% and 10%, respectively, suggests improving color reproduction and preventing color density losses. Optical analysis showed slight decrease in brightness and gloss, as was expected. Notably, the lightness was improved, which also indicates increasing color gamut volume in printing applications. As a result, the current work offers a sustainable approach to manage PMS for use in paper coatings as a high-value-added material.

3.
Chemosphere ; 334: 138966, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37220796

RESUMEN

The landfilling of paper mill sludge (PMS) has been restricted or even banned in many countries due to the raised concern about greenhouse gas (GHG) emissions and contamination of the soil and water, calling for a sustainable PMS management approach. The potential valorization of PMS to nanomaterials combined with traditional biorefinery was examined in this work. Three types of PMS-derived cellulose nanofibrils (CNFs) were prepared and evaluated: enzymatically assisted CNF (AU: with in-house produced enzyme and CT: with commercial enzyme), mechanically pretreated CNF (BT), and chemically pretreated CNF by TEMPO oxidation (TEMPO). It was found that enzyme-assisted mechanical fibrillation-derived CNFs had a comparable average diameter (27.9 nm for AU and 22.7 nm for CT) with that produced from mechanical pretreatment (26.5 nm for BT) and TEMPO oxidation pretreatment (20.0 nm for TEMPO), and they showed the best drainage properties among the three types of CNF. The CNFs resulting from enzymatic pretreatment reduced 15% of energy consumption compared to the mechanical method and had better thermostability than TEMPO oxidation method. In addition, the on-site produced enzyme showed similar performance to the commercial enzymes towards the CNF properties. These findings provide new insights into a promising integrated strategy in engineering CNF from PMS with on-site enzyme production as a novel and sustainable approach for PMS management and valorization.


Asunto(s)
Gases de Efecto Invernadero , Nanofibras , Celulosa/química , Aguas del Alcantarillado , Hidrólisis , Nanofibras/química
4.
Quintessence Int ; 53(9): 782-789, 2022 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-35726548

RESUMEN

OBJECTIVE: To evaluate the effects of zinc oxide-eugenol, calcium hydroxide, and mineral trioxide aggregate as base materials on the clinical and radiographic success of ferric sulfate pulpotomies in primary molars. METHOD AND MATERIALS: Following hemostasis with 15.5% ferric sulfate, 105 teeth were randomly allocated to three groups: Group 1, zinc oxide-eugenol; Group 2, calcium hydroxide; and Group 3, mineral trioxide aggregate. All teeth were restored with stainless-steel crowns. Clinical and radiographic examinations were conducted at 6, 12, 18, and 24 months. RESULTS: After 24 months, clinical success rates for Groups 1 to 3 were 97.1% (34/35 teeth), 94.2% (33/35 teeth), and 97.1% (34/35 teeth), respectively (P > .05). Radiographic success rates were 65.7% (23/35 teeth), 65.7% (23/35 teeth), and 77.1% (27/35 teeth), respectively (P > .05). Internal resorption was the most observed radiographic finding (15/105 teeth). CONCLUSIONS: The choice of zinc oxide-eugenol, calcium hydroxide, and mineral trioxide aggregate, as base materials, did not affect the clinical and radiographic success of ferric sulfate pulpotomies in primary teeth.


Asunto(s)
Pulpotomía , Óxido de Zinc , Compuestos de Calcio/uso terapéutico , Hidróxido de Calcio/farmacología , Hidróxido de Calcio/uso terapéutico , Combinación de Medicamentos , Eugenol/farmacología , Compuestos Férricos , Humanos , Diente Molar/cirugía , Óxidos/uso terapéutico , Pulpotomía/métodos , Silicatos/uso terapéutico , Acero/farmacología , Diente Primario , Resultado del Tratamiento , Óxido de Zinc/farmacología , Cemento de Óxido de Zinc-Eugenol/farmacología , Cemento de Óxido de Zinc-Eugenol/uso terapéutico
5.
Talanta ; 224: 121913, 2021 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-33379115

RESUMEN

The annual amount of food waste or loss is about one-third of the total edible food globally produced for human consumption. Continuous and real-time monitoring by spoilage detectors can significantly reduce food waste. A novel paper-based pH-sensitive meat spoilage detector was developed. A mixture of soybean hulls (SBHs) (hydrothermally-treated in an acidic environment), bentonite, and bromocresol purple (BCP) was coated on paper to produce the detector. The resultant meat spoilage detector was evaluated as a real-time freshness and spoilage indicator of catfish fillets (Ictalurus punctatus). Freshness and spoilage of fish meat with varying weights and headspace were determined by tailoring the detector's pH. Elemental, structural, and functional analysis verified the formation of a packed SBH-bentonite matrix with enhanced gas adsorption capacity and effective BCP-immobilization. Binder nanofibrillation increased the overall visual color vibrancy and decreased the binder demand in the coating formulation. Headspace volume in the studied range (40 and 160 cm3) did not affect the activation time of the detectors. However, increasing fish weight decreased the detectors' optimum activation time and pH. The findings of this study show that the developed detectors can be tailored for a wide range of sample and packaging sizes by simply adjusting the pH of the detector.


Asunto(s)
Embalaje de Alimentos , Eliminación de Residuos , Animales , Humanos , Concentración de Iones de Hidrógeno , Carne/análisis , Alimentos Marinos/análisis
6.
J Mich Dent Assoc ; 95(3): 58-62, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23777005

RESUMEN

Pulp necrosis is an uncommon sequel to extrusive luxation in immature teeth with incomplete apical closure. In this report, we describe the management of severely extruded immature maxillary incisors and the outcome of revascularization to treat subsequent pulp necrosis. An 8.5-year-old boy with severe dentoalveolar trauma to the anterior maxillary region as a result of a fall was provided emergency treatment consisting of reduction of the dislodged labial cortical bone and repositioning of the central incisors, which had suffered extrusive luxation. When he presented with spontaneous pain involving the traumatized incisors a week later, the teeth were treated via a revascularization protocol using sodium hypochlorite irrigation followed by 3 weeks of intracanal calcium hydroxide, then a coronal seal of mineral trioxide aggregate and resin composite. Complete periradicular healing was observed after 3 months, followed by progressive thickening of the root walls and apical closure. Follow-up observations confirmed the efficacy of the regenerative treatment as a viable alternative to conventional apexification in endodontically involved, traumatized immature teeth.

7.
Eur J Dent ; 7(Suppl 1): S060-S065, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24966730

RESUMEN

OBJECTIVE: The objective of this study was to evaluate the effect of operator variability on microleakage with different adhesive systems. MATERIALS AND METHODS: A total of 180 standardized Class V cavities were prepared on facial and lingual of 90 extracted human premolar teeth and randomly assigned to five groups according to the adhesive systems used (n = 36): Prime and Bond NT (PB), Single Bond (SB), Futura Bond NR, Xeno III (XE) and Adper Prompt-L-Pop (LP). The adhesive groups were then further subdivided into three operator groups according to level of clinical experience (n = 12): An undergraduate student, a research assistant and a faculty member. All cavities were restored with same composite resin. The restored teeth were thermocycled (500 cycles, 5-55°C) then immersed in 0.5% basic fuchsin and measured for leakage under a stereomicroscope. Statistical analyses were performed with the Kruskal-Wallis and Mann-Whitney U tests. RESULTS: Significant inter-operator variation was found in the enamel margins in the XE group with significantly higher microleakage when used by the undergraduate student (P < 0.05). Although no significant differences in microleakage were found between adhesive systems for the research assistant and faculty member (P > 0.05), significant differences were observed between PB and LP, PB and XE, SB and LP and SB and XE in the enamel margins for the undergraduate student (P < 0.05). CONCLUSION: Microleakage of adhesive systems is more dependent on interactions between the operator and adhesive material than on the choice of adhesive material.

8.
Tex Dent J ; 129(7): 675-81, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22916525

RESUMEN

Pulp necrosis is an uncommon sequel to extrusive luxation in immature teeth with incomplete apical closure. In this report, we describe the management of severely extruded immature maxillary incisors and the outcome of revascularization to treat subsequent pulp necrosis. An 8.5-year-old boy with severe dentoalveolar trauma to the anterior maxillary region as a result of a fall was provided emergency treatment consisting of reduction of the dislodged labial cortical bone and repositioning of the central incisors, which had suffered extrusive luxation. When he presented with spontaneous pain involving the traumatized incisors a week later, the teeth were treated via a revascularization protocol using sodium hypochlorite irrigation followed by 3 weeks of intracanal calcium hydroxide, then a coronal seal of mineral trioxide aggregate and resin composite. Complete periradicular healing was observed after 3 months, followed by progressive thickening of the root walls and apical closure. Follow-up observations confirmed the efficacy of the regenerative treatment as a viable alternative to conventional apexification in endodontically involved, traumatized immature teeth.


Asunto(s)
Necrosis de la Pulpa Dental/terapia , Pulpa Dental/irrigación sanguínea , Incisivo/lesiones , Neovascularización Fisiológica/fisiología , Irrigantes del Conducto Radicular/uso terapéutico , Tratamiento del Conducto Radicular/métodos , Avulsión de Diente/terapia , Compuestos de Aluminio/uso terapéutico , Coagulación Sanguínea , Compuestos de Calcio/uso terapéutico , Hidróxido de Calcio/uso terapéutico , Niño , Necrosis de la Pulpa Dental/etiología , Dentición Permanente , Combinación de Medicamentos , Humanos , Masculino , Óxidos/uso terapéutico , Regeneración , Materiales de Obturación del Conducto Radicular/uso terapéutico , Silicatos/uso terapéutico , Hipoclorito de Sodio/uso terapéutico , Ápice del Diente/crecimiento & desarrollo , Avulsión de Diente/complicaciones
9.
J Can Dent Assoc ; 78: c4, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22322021

RESUMEN

Pulp necrosis is an uncommon sequel to extrusive luxation in immature teeth with incomplete apical closure. In this report, we describe the management of severely extruded immature maxillary incisors and the outcome of revascularization to treat subsequent pulp necrosis. An 8.5-Year-old boy with severe dentoalveolar trauma to the anterior maxillary region as a result of a fall was provided emergency treatment consisting of reduction of the dislodged labial cortical bone and repositioning of the central incisors, which had suffered extrusive luxation. When he presented with spontaneous pain involving the traumatized incisors a week later, the teeth were treated via a revascularization protocol using sodium hypochlorite irrigation followed by 3 weeks of intracanal calcium hydroxide, then a coronal seal of mineral trioxide aggregate and resin composite. Complete periradicular healing was observed after 3 Months, followed by progressive thickening of the root walls and apical closure. Follow-up observations confirmed the efficacy of the regenerative treatment as a viable alternative to conventional apexification in endodontically involved, traumatized immature teeth.


Asunto(s)
Necrosis de la Pulpa Dental/etiología , Incisivo/irrigación sanguínea , Incisivo/lesiones , Avulsión de Diente/complicaciones , Avulsión de Diente/terapia , Reimplante Dental/métodos , Accidentes por Caídas , Compuestos de Aluminio/uso terapéutico , Compuestos de Calcio/uso terapéutico , Hidróxido de Calcio/uso terapéutico , Niño , Combinación de Medicamentos , Humanos , Incisivo/diagnóstico por imagen , Masculino , Maxilar/diagnóstico por imagen , Maxilar/lesiones , Óxidos/uso terapéutico , Radiografía , Silicatos/uso terapéutico , Hipoclorito de Sodio/uso terapéutico , Avulsión de Diente/diagnóstico por imagen
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