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A green synthesis of silver nanoparticles (AgNPs) was conducted by using Psidium guajava (P. guajava) leaf extract under light-emitting diodes (LED) irradiation. The obtained AgNPs were characterized by ultraviolet–visible spectroscopy, X-ray diffraction , energy-dispersive X-ray spectroscopy, Fourier-transform infrared spectroscopy, and transmission electron microscopy (TEM). In comparison to the absence of LED irradiation, the rate of AgNPs formation has been increased by more than twice with LED irradiation. Among LED irradiations, blue LED offered the most efficient in the formation of AgNPs. TEM analysis revealed that both AgNPs-N (without LED irradiation) and AgNPs-L (with LED irradiation) were nearly spherical with an average size of 32 nm.The antimicrobial assay indicated that AgNPs-L exhibited better antimicrobateria than AgNPs-N. The best antibacterial activity of AgNPs-L was recognized on L. fermentum (IC50 = 4.0 pM) for gram-negative bacteria, P. aeruginosa (IC50 = 3.5 pM) for gram-positive bacteria, and C. albicans (IC50 = 4.6 pM) for fungi.

The aim of this study was to investigate the total flavonoid content (TFC), vitamin C content, and the anti-hyperglycemic activities of pomelo peel extract (PPE) from the flavedo and albedo of two pomelo cultivars namely Long Co Co and Thanh Kieu in the Mekong Delta of Vietnam. Thanh Kieu PPE possessed the highest TFC of 11.18 ± 0.14 mg/100 g from the albedo while the highest vitamin C content was found in its flavedo (47.74 ± 0.34 mg/100 g). PPE from the flavedo induced the mortality after 3-4 h of oral administration at a dosage of 5000 mg/kg. In the contrast, PPE from the albedo was considered a non-toxic extract. Albedo PPE from two cultivars was observed to attenuate the blood glucose level of alloxan-hyperglycemia induced mice (from roughly 350 mg/dL to 150 mg/dL) and there was no significant difference in the anti-hyperglycemic efficacy between albedo PPE and chemical drug (Glucophage). This finding showed potential in developing new functional food products or pharmaceutical alternatives from pomelo peels (an agro-waste) for anti-hyperglycemia.

Background In a recent Phase 3 study (Study 4018) in HBV patients suppressed on TDF treatment, switching to TAF demonstrated non-inferior efficacy to continued TDF with superior bone and renal safety at Week 48. This study is to assess the safety and efficacy of switching to TAF from TDF in patients of Asian descent with risk factors for TDF toxicity as per current EASL and AASLD guidelines. Methods Virally suppressed patients (HBV DNA Results Among the 400 Asian patients enrolled, 288 (72%) had at least 1 TDF RF. At Week 48, similar proportions with ≥1 RF had HBV-DNA Conclusions Virally suppressed Asian patients with CHB and risk factors for TDF who switched to TAF showed improved bone and renal safety while efficacy was well-maintained.

Miliusa velutina (MV) stem bark has various medicinal uses, but its hepatoprotective effect has not yet been studied. This study investigated the antioxidant and hepatoprotective activity of the ethanol extract of MV stem bark against carbon tetrachloride (CCl4)-induced liver injury. The ethanol extract of MV stem bark was evaluated for in vitro antioxidant activity which exhibited good antioxidant activity in terms of ferric reducing-antioxidant power assay (EC50, FRAP=4.04±0.00 µg/mL), total antioxidant capacity assay (EC50, TAC=8.73±1.08 µg/mL) and 1,1-diphenyl-2-picrylhydrazyl (EC50, DPPH=9.33±0.07 µg/mL) radical scavenging assay. Mice were pretreated with CCl4 (2.5 mL/kg body wight per day) in 4 consecutive weeks. After one hour taking CCl4 by oral administration, mice were treated with the ethanol stem bark extract of MV at various concentrations of 100, 200, and 400 mg/kg body weight. The MV stem bark at the dose of 400 mg/kg body weight effectively reduced the level of alanine transaminase (38±6.78 U/L) and aspartate transaminase (AST) in serum. Besides, the MV stem bark at the dose 400 mg/kg body weight reduced the malondialdehyde (3.12±1,19 nM MDA/g tissue) level, and increased the activity of reduced glutathione (896.21±22.69 nM GSH/g tissue) in liver. The observation of the microscopic cross section of liver tissue also revealed that the mice treated with stem bark extract of MV at the dose of 200 and 400 mg/kg body weight had significantly improvement in liver tissues compared to the non-treated control group. Histological analyses of the MV-treated group exhibited reducing inflammatory process and preventing liver necrosis and fibrosis. In summary, the hepatoprotective effect of MV stem bark was seemingly associated with its antioxidant activity.

The subterranean termite Reticulitermes speratus usually nests in rotten wood trunks, which may also be occupied by the Japanese garden ant Lasius japonicus. Few battles were observed between them under ordinary circumstances because they inhabit separate nesting sites. However, once the termite nesting sites were artificially broken, the ant workers invaded and hunted the termites, although the termite soldiers fought against the ants. This study aims to confirm intra- and inter-specific chemical interactions between the termite and ant. Solid phase microextraction–gas chromatograph (SPME-GC) analyses revealed that R. speratus soldiers secreted caste-specific sesquiterpene hydrocarbon when they were irritated. Both the hexane extract of the soldiers and its hydrocarbon fraction, as well as the crushed soldier bodies, attracted the soldiers but dispersed the workers when presented on the trails. We also confirmed that the soldier chemicals enhanced aggressiveness of L. japonicus, which rushed around the odor sources and hunted any termites that were present. These findings suggest that: (i) the soldier–specific secretion might serve as an alarm pheromone in termite chemical communication, in which components recruit soldiers and also warn the other colony members away; and (ii) termite communication is eavesdropped on by L. japonicus workers to locate and hunt the termites.

Euphorbia hirta L., a kind of herbs belonging to family Euphorbiaceae, has been found a lot in the Mekong Delta. From the ethyl acetat and methanol fractions of this plant, four pure compounds were isolated and identified their chemical structure by spectroscopic techniques including quercitrin (1), luteolin (2), quercetin (3) and caffeic acid (4). The effect of crude ethanolic extract and some fractioned extracts as well as four isolated compounds from E hirta L., collected in the Mekong Delta, on endoplasmic reticulum stress-induced cell death in mouse β-cell lines was investigated. The results showed that methanol fraction and a isolated compound, quercitrin gave strong cell-protective effect with the cell viability of 69% and 78% at the dose of 100 µg/mL and 10 µg/mL, respectively. This proves that E hirta L. might have anti-diabetic effects and worth conducting further pharmacological investigations related to type 2 diabetes mellitus.

This paper proposes a pseudo-gradient based particle swarm optimization with constriction factor (PG-PSOCF) method for solving multiobjective optimal power flow (MOOPF) problem. The proposed PG-PSOCF is the conventional particle swarm optimization based on constriction factor based on pseudo gradient to enhance its search ability for optimization problems. The proposed method is to deal with the MOOPF problem by minimizing the total cost and emission from generators while satisfying various constraints of real and reactive power balance, real and reactive power limits, bus voltage limits, shunt capacitor limits and transmission limits. Test results on the IEEE 30-bus system have indicated that the proposed method is more efficient than many other methods in the literature. Therefore, the proposed PG-PSOCF can be an effectively alternative method for solving the MOOPF problem.