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Fulltext Optimization of a Luteolin-Loaded TPGS/Poloxamer 407 Nanomicelle: The Effects of Copolymers, Hydration Temperature and Duration, and Freezing Temperature on Encapsulation Efficiency, Particle Size, and Solubility

Mod Razif MRF, Chan SY, Widodo RT, Chew YL, Hassan M, Hisham SA, et al.

Cancers (Basel), 2023 Jul 24;15(14).
PMID: 37509402 DOI: 10.3390/cancers15143741

BACKGROUND: Luteolin is a flavonoid compound that has been widely studied for its various anti-cancer properties and sensitization to multidrug-resistant cells. However, the limited solubility and bioavailability of Lut hindered its potential clinical use. Theoretically, the combination of this compound with vitamin E TPGS and poloxamer 407 can produce a synergistic effect to enhance tumor apoptosis and P-glycoprotein inhibition. This study aimed to develop and optimize vitamin E TPGS/Poloxamer 407 micelles loaded with luteolin through investigating certain factors that can affect the encapsulation efficiency and particle size of the micelle.
METHODS: A micelle was prepared using the film hydration method, and the micellar solution was lyophilized. The cake formed was analyzed. The factors investigated include the concentrations of the surfactants, ratio of vitamin E TPGS/Poloxamer 407, temperature of the hydrating solution, duration of hydration, and freezing temperature before lyophilization. The effects of these factors on the encapsulation efficiency and particle size of the micelle were also studied. The encapsulation efficiency was measured using a UV-Vis spectrophotometer, while particle size was measured using dynamic light scattering.
RESULTS: The optimized micelle was found to have 90% encapsulation efficiency with a particle size of less than 40 nm, which was achieved using a 10% concentration of surfactants at a vitamin E TPGS/Poloxamer 407 ratio of 3:1. The optimized temperature for hydrating the micellar film was 40 °C, the optimized mixing time was 1 h, and the optimized freezing temperature was -80 °C. The solubility of the luteolin-loaded micelles increased 459-fold compared to pure Lut in water. The critical micelle concentration of the vitamin E TPGS/Poloxamer 407 micelle was 0.001 mg/mL, and the release study showed that luteolin-loaded micelles exhibited sustained release behavior. The release of luteolin from a micelle was found to be higher in pH 6.8 compared to pH 7.4, which signified that luteolin could be accumulated more in a tumor microenvironment compared to blood.
CONCLUSION: This study demonstrated that several factors need to be considered when developing such nanoparticles in order to obtain a well-optimized micelle.
Fulltext A single epitope of Epstein-Barr Virus stimulate IgG production in mice

Widodo, Pristiwanto B, Rifa'i M, Mustafa I, Huyop FZ

Ann Med Surg (Lond), 2018 Nov;35:55-58.
PMID: 30294429 DOI: 10.1016/j.amsu.2018.09.014

Background: Epstein-Barr virus (EBV) is closely associated with the high incidence of nasopharyngeal carcinoma in worldwide. Vaccination is one strategy with the potential to prevent the occurrence of EBV-associated cancers, but a suitable vaccine is yet to be licensed. Much vaccine development research focuses on the GP350/220 protein of EBV as it contains an immunogenic epitope at residues 147-165, which efficiently stimulates IgG production in vitro. We examined the ability of this epitope (EBVepitope) to induce IgG production in mice.
Methods: The antibody binding pattern of the epitope was analyzed using bioinformatics tools. The IgG production in mice were examined by FACS Calibur™ Flow cytometer.
Results: The epitope bound the 72A1 monoclonal antibody at the same site as GP350/220 protein, indicating that the epitope should stimulate B cells to produce antibody. Moreover, in vivo administration of EBVepitope successfully induced IgG expression from B cells, compared with controls. Further investigation indicated that the relative number of B cells expressing IgE in EBVepitope-treated mice was lower than controls.
Conclusions: Our data suggest that this EBV GP350 epitope is able to induce IgG expression in vivo without causing allergic reactions, and represents a potential EBV vaccine candidate.
Fulltext Recovery planning towards doubling wild tiger Panthera tigris numbers: Detailing 18 recovery sites from across the range

Harihar A, Chanchani P, Borah J, Crouthers RJ, Darman Y, Gray TNE, et al.

PLoS One, 2018;13(11):e0207114.
PMID: 30408090 DOI: 10.1371/journal.pone.0207114

With less than 3200 wild tigers in 2010, the heads of 13 tiger-range countries committed to doubling the global population of wild tigers by 2022. This goal represents the highest level of ambition and commitment required to turn the tide for tigers in the wild. Yet, ensuring efficient and targeted implementation of conservation actions alongside systematic monitoring of progress towards this goal requires that we set site-specific recovery targets and timelines that are ecologically realistic. In this study, we assess the recovery potential of 18 sites identified under WWF's Tigers Alive Initiative. We delineated recovery systems comprising a source, recovery site, and support region, which need to be managed synergistically to meet these targets. By using the best available data on tiger and prey numbers, and adapting existing species recovery frameworks, we show that these sites, which currently support 165 (118-277) tigers, have the potential to harbour 585 (454-739) individuals. This would constitute a 15% increase in the global population and represent over a three-fold increase within these specific sites, on an average. However, it may not be realistic to achieve this target by 2022, since tiger recovery in 15 of these 18 sites is contingent on the initial recovery of prey populations, which is a slow process. We conclude that while sustained conservation efforts can yield significant recoveries, it is critical that we commit our resources to achieving the biologically realistic targets for these sites even if the timelines are extended.
Fulltext Author Correction: Perceptions of the appropriate response to norm violation in 57 societies

Eriksson K, Strimling P, Gelfand M, Wu J, Abernathy J, Akotia CS, et al.

Nat Commun, 2021 Apr 26;12(1):2483.
PMID: 33903599 DOI: 10.1038/s41467-021-22955-x
Fulltext Perceptions of the appropriate response to norm violation in 57 societies

Eriksson K, Strimling P, Gelfand M, Wu J, Abernathy J, Akotia CS, et al.

Nat Commun, 2021 03 05;12(1):1481.
PMID: 33674587 DOI: 10.1038/s41467-021-21602-9

Norm enforcement may be important for resolving conflicts and promoting cooperation. However, little is known about how preferred responses to norm violations vary across cultures and across domains. In a preregistered study of 57 countries (using convenience samples of 22,863 students and non-students), we measured perceptions of the appropriateness of various responses to a violation of a cooperative norm and to atypical social behaviors. Our findings highlight both cultural universals and cultural variation. We find a universal negative relation between appropriateness ratings of norm violations and appropriateness ratings of responses in the form of confrontation, social ostracism and gossip. Moreover, we find the country variation in the appropriateness of sanctions to be consistent across different norm violations but not across different sanctions. Specifically, in those countries where use of physical confrontation and social ostracism is rated as less appropriate, gossip is rated as more appropriate.