MyMedR

Displaying all 4 publications

Abstract:

Sort:

Studies on the effects of titanate and silane coupling agents on the performance of poly (methyl methacrylate)/barium titanate denture base nanocomposites

Elshereksi NW, Ghazali MJ, Muchtar A, Azhari CH

J Dent, 2017 Jan;56:121-132.
PMID: 27916635 DOI: 10.1016/j.jdent.2016.11.012

OBJECTIVES: This study aimed to fabricate and characterise silanated and titanated nanobarium titanate (NBT) filled poly(methyl methacrylate) (PMMA) denture base composites and to evaluate the behaviour of a titanate coupling agent (TCA) as an alternative coupling agent to silane. The effect of filler surface modification on fracture toughness was also studied.
METHODS: Silanated, titanated and pure NBT at 5% were incorporated in PMMA matrix. Neat PMMA matrix served as a control. NBT was sonicated in MMA prior to mixing with the PMMA. Curing was carried out using a water bath at 75°C for 1.5h and then at 100°C for 30min. NBT was characterised via Fourier transform-infrared spectroscopy (FTIR), Transmission Electron Microscopy (TEM) and Brunauer-Emmett-Teller (BET) analysis before and after surface modification. The porosity and fracture toughness of the PMMA nanocomposites (n=6, for each formulation and test) were also evaluated.
RESULTS: NBT was successfully functionalised by the coupling agents. The TCA exhibited the lowest percentage of porosity (0.09%), whereas silane revealed 0.53% porosity. Statistically significant differences in fracture toughness were observed among the fracture toughness values of the tested samples (p<0.05). While the fracture toughness of untreated samples was reduced by 8%, an enhancement of 25% was achieved after titanation. In addition, the fracture toughness of the titanated samples was higher than the silanated ones by 10%.
CONCLUSION: Formation of a monolayer on the surface of TCA enhanced the NBT dispersion, however agglomeration of silanated NBT was observed due to insufficient coverage of NBT surface. Such behaviour led to reducing the porosity level and improving fracture toughness of titanated NBT/PMMA composites. Thus, TCA seemed to be more effective than silane.
CLINICAL SIGNIFICANCE: Minimising the porosity level could have the potential to reduce fungus growth on denture base resin to be hygienically accepTable Such enhancements obtained with Ti-NBT could lead to promotion of the composites' longevity.
Acute effects of a single dose of tocotrienols on insulinemic and inflammatory responses in metabolic syndrome subjects after a high-fat challenge

Che HL, Kanthimathi MS, Loganathan R, Yuen KH, Tan AT, Selvaduray KR, et al.

Eur J Clin Nutr, 2017 01;71(1):107-114.
PMID: 27759074 DOI: 10.1038/ejcn.2016.200

BACKGROUND/OBJECTIVES: Evidence shows that tocotrienols potentially reverse various chronic disease progressions caused by the metabolic syndrome. We aimed to investigate the acute effects of a single-dose supplementation of gamma and delta tocotrienols (γδ-T3, 1:4 ratio) compared with those in placebo on the insulinemic, anti-inflammatory and anti-thrombogenic responses in metabolic syndrome subjects.
SUBJECTS/METHODS: Thirty metabolic syndrome subjects (15 men and 15 women) were recruited to a randomized, double-blinded and crossover study. The subjects were administered a single dose of 200 mg or 400 mg γδ-T3 emulsions or placebo incorporated into a glass of strawberry-flavored milkshake, consumed together with a high-fat muffin. Blood samples were collected at 0, 5, 15, 30, 60, 90, 120, 180, 240, 300 and 360 min after meal intake.
RESULTS: Plasma vitamin E levels reflected the absorption of γδ-T3 after treatments. Postprandial changes in serum C-peptide, serum insulin, plasma glucose, triacylglycerol, non-esterified fatty acid and adiponectin did not differ between treatments, with women displaying delayed increase in the aforementioned markers. No significant difference between treatments was observed for plasma cytokines (interleukin-1 beta, interleukin-6 and tumor necrosis factor alpha) and thrombogenic markers (plasminogen activator inhibitor type 1 and D-dimer).
CONCLUSIONS: Supplementation of a single dose of γδ-T3 did not change the insulinemic, anti-inflammatory and anti-thrombogenic responses in metabolic syndrome subjects.
A comparative study based on performance and techno-economic analysis of different strategies for PV-Electrolyzer (green) hydrogen fueling incinerator system

Majeed Butt O, Shakeel Ahmad M, Kai Lun T, Seng Che H, Fayaz H, Abd Rahim N, et al.

Waste Manag, 2023 Feb 01;156:1-11.
PMID: 36424243 DOI: 10.1016/j.wasman.2022.11.016

The integration of hydrogen in the primary energy mix requires a major technological shift in virtually every energy-related application. This study has attempted to investigate the techno-economic solar photovoltaic (PV) integrated water electrolysis and waste incineration system. Three different strategies, i.e., (i) PV + Battery(Hybrid mode with required batteries); (ii) auto-ignition (Direct coupling); and (iii) PV + Secondary-Electrolyzer(Direct coupling assisted with secondary electrolyzer), have been envisioned. The 'PV + Battery' consume 42.42 % and 15.07 % less energy than the auto-ignition and 'PV + Secondary-Electrolyzer' methods. However, the capital cost of 'PV + Battery' has been calculated to be 15.4 % and 11.8 % more than auto-ignition and 'PV + Secondary-Electrolyzer, respectively.The energy consumption relative to waste input, the 'PV + Battery' method used 80 % less energy, while auto-ignition and 'PV + Secondary-Electrolyzer' showed 70.5 % and 77.5 % less energy, respectively. Furthermore, these approaches showed a vast difference in cost-benefit for the longer run. 'PV + Battery' was forecasted to be 73.3 % and 23.3 % more expensive than auto-ignition and 'PV + Secondary-Electrolyzer' methods, respectively, for 30 years. Overall, this study can benefit from using either of these methods depending on the application, usage scale, and climatic conditions.
Dosage-dependent effects of Semen Ziziphi Spinosae on post-acidification inhibition, protein structure and functional properties of goat milk fermented by Lactiplantibacillus plantarum

Wang Q, Nie M, Yang T, Che H, Shi Y, Cui C, et al.

J Sci Food Agric, 2026 Nov 03.
PMID: 42978181 DOI: 10.1002/jsfa.71128

BACKGROUND: This study aimed to prepare fermented goat milk yogurt (GMY) with graded Semen Ziziphi Spinosae (SZS) supplementation (0.0-2.5 g kg-1), and to explore the regulatory effects and underlying molecular mechanisms of SZS on gel properties, physicochemical quality and protein conformation of GMY co-fermented by Lactiplantibacillus plantarum L3 and commercial starter (YO-MIX 883 containing Streptococcus thermophilus and Lactobacillus delbrueckii subsp. bulgaricus). Physicochemical and antioxidant properties were assayed. Spectroscopic measurements coupled with particle-size and zeta-potential analyses characterized protein-conformational and colloidal-structure variations.
RESULTS: All GMY exhibited post-acidification during storage. The amount of 0.5-1.0 g kg-1 SZS raised titratable acidity, while 1.5-2.5 g kg-1 restrained acid accumulation. SZS dose-dependently increased hardness and consistency and reduced cohesiveness and adhesiveness; 2.0-2.5 g kg-1 groups showed the densest gel. SZS decreased particle size and raised absolute zeta potential to stabilize casein micelles, reduced L* and elevated total color difference (ΔE), turning samples creamy yellow. It remarkably improved DPPH and ABTS scavenging capacity, with the 2.5 g kg-1 group hitting 93.30 g 100 g-1. Fourier-transform infrared (FTIR), Raman and intrinsic fluorescence spectroscopy verified protein secondary structure rearrangement and reconstructed intermolecular forces. It was found 2.0 g kg-1 was the optimal dosage; overdose disrupted colloidal and protein conformational stability. SZS optimized casein polysaccharide networks through hydrogen, hydrophobic and electrostatic interactions.
CONCLUSION: Appropriate SZS supplementation achieved optimal quality regulation of GMY with substantially enhanced storage stability, gel texture and antioxidant activity. This study uncovered the molecular mechanism by which natural plant bioactive compounds improve fermented milk quality via regulating protein conformation and non-covalent interactions, providing theoretical support for the targeted formulation design of functional fermented dairy products. © 2026 Society of Chemical Industry.