Antibacterial Activity of Green-Synthesized Silver Nanoparticles Using Areca catechu Extract against Antibiotic-Resistant Bacteria.

In this work, the antibacterial activity of silver nanoparticles (AgNPs) synthesized using Areca catechu extracts against three species of antibiotic-susceptible and three species of resistant bacteria was investigated. The effects of this plant were more promising when compared with other medicinal plants tested. The hydrothermal extract of Areca catechu was mixed with silver nitrate to synthesize AgNPs. The synthesized particle characteristics were analyzed by UV-Vis spectrophotometry, scanning electron microscopy (SEM), dynamic light scattering (DLS), and Fourier-transform infrared spectroscopy (FT-IR). Minimum inhibitory concentration and minimum bactericidal concentration tests were conducted to confirm antibacterial activity and the results showed that AgNPs synthesized using Areca catechu extracts effectively inhibited the growth of bacterial species. Moreover, the SEM images of the bacterial species treated with AgNPs synthesized with Areca catechu extracts showed that clusters of AgNPs were attached to the surface of the bacterial cell wall, which could induce destruction of the cell membranes. The results suggest that AgNPs synthesized with Areca catechu extracts have the potential to treat antibiotic-resistant bacteria known as the major cause of nosocomial infections.

Development of a 68 Ga-labelled PET tracer for carbonic anhydrase IX-overexpressed tumors using the artificial sweetener saccharin.

In this study, we developed a saccharin (SAC)-based radiopharmaceutical (68 Ga-NOTA-SAC) and evaluated the possibility of its application as a PET tracer in the diagnosis of carbonic anhydrase IX (CA IX)-overexpressed tumors. We did a water-soluble tetrazolium assay and flow cytometry analysis to identify the cell viability decrease by SAC. The radiochemical purity and stability of 68 Ga- NOTA-SAC in human and mouse serum was greater than 98%. The small animal PET image-based radioactivity distribution of all organs decreased over time.68 Ga-NOTA-SAC presented the highest tumor-to-muscle ratio at 90 min post injection (p.i). The growth rates of tumor-to-muscle ratios of 68 Ga-NOTA-SAC were 88% at 60 min and 220% at 90 min, compared to 30 min p.i. The potential of 68 Ga-NOTA-SAC as a PET tracer is expected to contribute to the diagnostic research on CA IX-overexpressed tumors with the advantages of a relatively simple synthesis method.

Beneficial effects of weekend catch-up sleep on metabolic syndrome in chronic short sleepers.

OBJECTIVES: Short sleep duration has been known to be related to metabolic syndrome (MetS) . The aim of this study was to investigate the beneficial effects of weekend catch-up sleep (WCUS) on MetS in the Korean middle-aged population. METHODS: For this cross-sectional study, 1,812 participants aged 35-60 years were selected from the 2016-2018 Korean National Health and Nutrition Examination Survey (mean age 46.94 years, 49% male). Short sleep duration was defined as <6hrs on weekdays, and participants were divided into two groups: WCUS group and no weekend catch-up sleep group. Multiple logistic regression was performed to determine the association between WCUS and MetS prevalence. The covariates included age, sex, education, income, occupation, smoking, alcohol consumption, and physical activity. RESULTS: WCUS was significantly associated with lower MetS prevalence in the unadjusted model and in the model adjusted for socioeconomic and health behavior factors. CONCLUSION: These results support the beneficial effects of WCUS on lowering the risk of MetS among middle-aged chronic short sleepers.

Inhibitory Activity of Silver Nanoparticles Synthesized Using Lycopersicon Esculentum against Biofilm Formation in Candida Species.

This paper investigated the antifungal and antibiofilm activity of silver nanoparticles synthesized with Lycopersicon esculentum extracts against Candida species. Lycopersicon esculentum extracts obtained by homogenization were mixed with silver nitrate to synthesize silver nanoparticles. Analysis of the particle characteristics by UV-Vis spectrophotometry, scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDAX), dynamic light scattering (DLS), and Fourier transform infrared spectroscopy (FT-IR) confirmed that the Lycopersicon esculentum extracts effectively served as reductants and capping agents. Minimum inhibitory concentration (MIC) tests were conducted to confirm antifungal activity against Candida species. In all the tested species, the silver nanoparticles inhibited the growth of Candida. Moreover, the SEM images of Candida species treated with silver nanoparticles synthesized using natural extracts of Lycopersicon esculentum showed that silver nanoparticles adhered to the surface of Candida, which induced pore formation in the membranes and prevented their normal growth. Ultimately, these abnormal forms of Candida were thought to be less able to form biofilms than normal Candida. The antifungal and antibiofilm activities of silver nanoparticles against Candida are expected to be utilized in various fields and contribute in particular to developments in nanomedicine.

Inhibitory activity of hinokitiol against biofilm formation in fluconazole-resistant Candida species.

The aim of this study was to investigate the ability of hinokitiol to inhibit the formation of Candida biofilms. Biofilm inhibition was evaluated by quantification of the biofilm metabolic activity with XTT assay. Hinokitiol efficiently prevented biofilm formation in both fluconazole-susceptible and fluconazole-resistant strains of Candida species. We determined the expression levels of specific genes previously implicated in biofilm development of C. albicans cells by real-time RT-PCR. The expression levels of genes associated with adhesion process, HWP1 and ALS3, were downregulated by hinokitiol. Transcript levels of UME6 and HGC1, responsible for long-term hyphal maintenance, were also decreased by hinokitiol. The expression level of CYR1, which encodes the component of signaling pathway of hyphal formation-cAMP-PKA was suppressed by hinokitiol. Its upstream general regulator RAS1 was also suppressed by hinokitiol. These results indicate that hinokitiol may have therapeutic potential in the treatment and prevention of biofilm-associated Candida infections.